No abstract available
Τετάρτη 26 Σεπτεμβρίου 2018
In Search of an Ideal Closure Method: A Randomized, Controlled Trial of Octyl-2-Cyanoacrylate and Adhesive Mesh versus Subcuticular Suture in Reduction Mammaplasty
Background: An ideal wound closure system is one that is effective, consistent, and efficient. Recent studies have demonstrated the efficacy of octyl-2-cyanoacrylate and mesh (Dermabond Prineo) in the closure of surgical wounds. This study compared the use of Prineo to use of subcuticular suture closure in reduction mammaplasty. Methods: A prospective, randomized, controlled, single-blind study of patients undergoing bilateral reduction mammaplasty was performed. Each breast per patient was randomized to layered closure with Prineo or subcuticular sutures. Incisions were assessed at 2 weeks, 6 weeks, 6 months, and 1 year. Subjects completed the Patient and Observer Scar Assessment Scale for each breast, and two blinded plastic surgeons evaluated scar quality using the Vancouver Scar Scale at each time point. Results: Twenty-one patients participated in the study. On average, Prineo closure took 58.38 seconds (2.50 seconds/cm) and subcuticular closure took 444.76 seconds (18.94 seconds/cm). Prineo closure was approximately 6.8 times faster (pTreatment of Infected Wounds in the Age of Antimicrobial Resistance: Contemporary Alternative Therapeutic Options
Summary: As antibiotic resistance increases and antimicrobial options diminish, there is a pressing need to identify and develop new and/or alternative (non–antimicrobial-based) wound therapies. The authors describe the implications of antibiotic resistance on their current wound treatment paradigms and review the most promising non–antibiotic-based antimicrobial agents currently in research and development, with a focus on preclinical and human studies of therapeutic bacteriophages, antimicrobial peptides, cold plasma treatment, photodynamic therapy, honey, silver, and bioelectric dressings.The Influence of Physician Payments on the Method of Breast Reconstruction: A National Claims Analysis
Background: Flap-based breast reconstruction demands greater operative labor and offers superior patient-reported outcomes compared with implants. However, use of implants continues to outpace flaps, with some suggesting inadequate remuneration as one barrier. This study aims to characterize market variation in the ratio of implants to flaps and assess correlation with physician payments. Methods: Using the Blue Health Intelligence database from 2009 to 2013, patients were identified who underwent tissue expander (i.e., implant) or free-flap breast reconstruction. The implant-to-flap ratio and physician payments were assessed using quadratic modeling. Matched bootstrapped samples from the early and late periods generated probability distributions, approximating the odds of surgeons switching reconstructive method. Results: A total of 21,259 episodes of breast reconstruction occurred in 122 U.S. markets. The distribution of implant-to-flap ratio varied by market, ranging from the fifth percentile at 1.63 to the ninety-fifth percentile at 43.7 (median, 6.19). Modeling the implant-to-flap ratio versus implant payment showed a more elastic quadratic equation compared with the function for flap-to-implant ratio versus flap payment. Probability modeling demonstrated that switching the reconstructive method from implants to flaps with a 0.75 probability required a $1610 payment increase, whereas switching from flaps to implants at the same certainty occurred at a loss of $960. Conclusions: There was a correlation between the ratio of flaps to implants and physician reimbursement by market. Switching from implants to flaps required large surgeon payment increases. Despite a relative value unit schedule over twice as high for flaps, current flap reimbursements do not appear commensurate with physician effort.
Accuracy of Three Software Applications for Breast Volume Calculations from Three-Dimensional Surface Images
Background: Knowing breast volumes before certain surgeries helps the surgeon to obtain breast symmetry. Calculating breast volumes from three-dimensional surface images is possible with specialized software applications. However, limited data exist concerning the accuracy of such volume calculations. The purpose of this study was to investigate the accuracy of breast volume calculations performed with the 3D BreAST, 3dMD Vultus, and VECTRA software applications. Methods: Twenty-six subjects who underwent 44 mastectomies were enrolled. Preoperative three-dimensional surface images were acquired with a VECTRA-XT stereophotogrammetry device. Breast volumes were calculated from these images with the three software applications. The mastectomy specimens were weighed to derive their actual volume and compared with the software calculations. Results: For all three methods, a positive correlation between the breast volume and absolute calculation error was found (pPreoperative Multimodal Analgesia Decreases Postanesthesia Care Unit Narcotic Use and Pain Scores in Outpatient Breast Surgery
Background: The opioid epidemic demands changes in perioperative pain management. Of the 33,000 deaths attributable to opioid overdose in 2015, half received prescription opioids. Multimodal analgesia is a practice-altering evolution that reduces reliance on opioid medications. Ambulatory breast surgery is an ideal opportunity to implement these strategies. Methods: A retrospective review of 560 patients undergoing outpatient breast procedures was conducted. Patients received (1) no preoperative analgesia (n = 333); (2) intraoperative intravenous acetaminophen (n = 78); (3) preoperative oral acetaminophen and gabapentin (n = 95); or (4) preoperative oral acetaminophen, gabapentin and celecoxib (n = 54). Outcomes included postanesthesia care unit narcotic use, pain scores, postanesthesia care unit length of stay, rescue antiemetic use, and 30-day complications. Results: Both oral multimodal analgesia regimens significantly reduced postanesthesia care unit narcotic use (oral acetaminophen and gabapentin, 14.3 ± 1.7; oral gabapentin, acetaminophen, and celecoxib, 11.9 ± 2.2; versus no drug, 19.2 ± 1.1 mg oral morphine equivalents; p = 0.0006), initial pain scores (oral acetaminophen and gabapentin, 3.9 ± 0.4; oral gabapentin, acetaminophen, and celecoxib, 3.4 ± 0.7; versus no drug, 5.3 ± 0.3 on a 1 to 10 scale, p = 0.0002) and maximum pain scores (oral acetaminophen and gabapentin, 4.3 ± 0.4; oral gabapentin, acetaminophen, and celecoxib, 3.6 ± 0.7; versus no drug, 5.9 ± 0.3 on a 1 to 10 scale; pUse of Composite Arterial and Venous Grafts in Microsurgical Breast Reconstruction: Technical Challenges and Lessons Learned
Summary: The success of microvascular reconstruction depends on many factors. Although many factors cannot be dictated by a surgeon, the success of anastomosis can be maximized by honing skill with performing anastomoses. However, size discrepancy of vessels remains a common challenge, given the lack of an ideal technique. In this study, the authors introduce their experience in using composite deep inferior epigastric arterial and venous grafts to overcome the vessel size and pedicle length discrepancy in lateral thigh and superficial inferior epigastric artery (SIEA) flaps. Of the 1095 flaps performed, the authors identified a total of 12 flaps (one lateral thigh flap and 11 SIEA flaps) on nine patients for breast reconstruction. The authors used deep inferior epigastric vessels to act as interposition grafts between the internal mammary artery and flap pedicle. For the SIEA flaps, the authors anastomosed the SIEA system to the deep inferior epigastric arterial system, checked the viability of the flap, and then transferred the flap to the internal mammary artery and flap pedicle. For the SIEA flaps, the authors anastomosed the SIEA system to the deep inferior epigastric arterial system, checked the viability of the flap, and then transferred the flap to the internal mammary artery system in three patients. In the last five patients, the authors anastomosed the deep inferior epigastric vessels to the internal mammary artery system first, and then transferred the SIEA flap. For the lateral thigh flap, the authors anastomosed grafts to the internal mammary artery system first as well. There were no flap losses or fat necrosis. Although the authors' outcomes are limited to only breast reconstruction, they believe this method could be expanded to different types of reconstruction, especially reconstruction of the head and neck.
Current Approaches to Prepectoral Breast Reconstruction
Summary: Prepectoral prosthetic breast reconstruction has become an acceptable option for women following mastectomy. Benefits include no animation deformity, absence of pectoralis major muscle spasm, and less pain and discomfort. Important aspects of prepectoral reconstruction include working with breast surgeons that are adept at performing an optimal mastectomy. Tissue perfusion and reasonable thickness of the mastectomy are critical components of success. Tissue necrosis, infection, and delayed healing can lead to reconstructive failure. Given the risks and benefits of this procedure, questions regarding indications, patient selection, and specific details related to technique remain because there is no consensus. Whether it is safe to perform prepectoral reconstruction in obese or previously irradiated patients is controversial. The use of acellular dermal matrix is common but not universal. The amount of acellular dermal matrix used is variable, with success being demonstrated with the partial and total wrap techniques. Device selection can vary but is critical in the prepectoral setting. Postoperative care and the management of adverse events are important to understand and can impact surgical and aesthetic outcomes. This article provides current approaches, recommendations, and an algorithm for prepectoral breast reconstruction with an emphasis on patient selection, immediate versus delayed prepectoral reconstruction, specific technical details, and postoperative management.
The Public Face of Rhinoplasty: Impact on Perceived Attractiveness and Personality
Background: The authors assess the impact of rhinoplasty on public perception of a patient's appearance and personality. Methods: A survey was created using standardized before-and-after photographs of 10 Caucasian women who had undergone primary rhinoplasty. Photographs of two additional women who had not undergone facial surgery were randomly included as controls, for a total of 12 survey items. Preoperative and postoperative photographs were placed side by side. The survey was administered by means of crowd-sourcing. Respondents were asked to evaluate which photograph better represented 11 traits of appearance or personality, according to a seven-point Likert scale. A score of 1 meant the preoperative photograph was much better, 7 meant the postoperative photograph was much better, and 4 meant no difference. T tests and analyses of variance were used to evaluate rating changes for each trait and differences between demographic groups. Results: There were 264 responses received. Averaged scores across the 10 survey patients produced a value for each appearance or personality trait. In 10 of 11 categories (i.e., symmetry, youthfulness, facial harmony, likeability, trustworthiness, confidence, femininity, attractiveness, approachability, and intelligence), the postoperative photograph was significantly favorable compared with the preoperative photograph (pThe Orbital Oval Balance Principle: A Morphometric Clinical Analysis
Background: The aim of this study was to test the validity of the "orbital oval balance principle," a system of analysis and guideline that is used among aestheticians, artists, and makeup artists to create and design aesthetically pleasing eyebrows for optimal upper facial appearance. According to this principle, a face is optimally attractive when the eye is centered in an "oval" defined by the lid-cheek junction and the eyebrow. Methods: One hundred participants were asked to rank digital morphed images of four female models with four different periorbital proportions: higher or lower lid-cheek junction versus higher or lower eyebrow position. In addition, the participants were asked to quantify seven emotions on these morphed images. Results: A higher lid-cheek junction was rated as significantly more attractive with a lower eyebrow position, and a lower lid-cheek junction was regarded far more attractive in combination with a higher eyebrow position. Moreover, a higher lid-cheek junction was rated as more attractive than a lower lid-cheek junction, and elevation of the lid-cheek junction improved the perception of emotions such as tiredness and sadness. Conclusions: This study lends support to the orbital oval balance principle that can provide important insight into facial attractiveness to surgeons undertaking procedures intended to improve and rejuvenate facial appearance. Moreover, this study has also shown not only that a high(er) lid-cheek junction is regarded as more youthful and attractive, but that it also may reduce the appearance of tiredness and sadness.Abdominoplasty with Circumferential Liposuction: A Review of 1000 Consecutive Cases
Background: The authors present the technique called "abdominoplasty with concurrent circumferential liposuction," where the whole trunk is addressed as a single aesthetic unit. Methods: Between January of 2008 and June of 2016, abdominoplasty with circumferential liposuction was performed in 1000 patients (984 women and 16 men) by the senior author. Patients had a mean body mass index of 27.5 kg/m2 (range, 18.1 to 34.5 5 kg/m2). Liposuction was performed circumferentially and the abdominal flap was detached up to the costal margins. Simultaneous fat grafting was also performed if required. Outcomes and complications were documented. Results: Traditional abdominoplasty incisions were used in 359 patients, whereas extended incisions were used in 641 patients. The mean duration of follow-up was 27 months (range, 12 days to 61 months), and the mean duration of surgery was 154 minutes (range, 109 to 260 minutes). The mean amount of simultaneously aspired supernatant lipoaspirate was 1940 cc (range, 1700 to 4580 cc). Simultaneous gluteal fat grafting was performed in 34 percent. None of the patients had any skin necrosis. The most common complication was seroma (19 percent). Conclusions: In abdominoplasty, the entire central body should be considered as a single unit. Circumferential widespread liposuction with standard undermining of the abdominal flap up to the costal margins is safe and yields superior aesthetic outcomes. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.Isolation, characterization, genomic sequencing, and GFP-marked insertional mutagenesis of a high-performance nitrogen-fixing bacterium, Kosakonia radicincitans GXGL-4A and visualization of bacterial colonization on cucumber roots
Abstract
A gram-negative bacterium GXGL-4A was originally isolated from maize roots. It displayed nitrogen-fixing (NF) ability under nitrogen-free culture condition, and had a significant promotion effect on cucumber growth in the pot inoculation test. The preliminary physiological and biochemical traits of GXGL-4A were characterized. Furthermore, a phylogenetic tree was constructed based on 16S ribosomal DNA (rDNA) sequences of genetically related species. To determine the taxonomic status of GXGL-4A and further utilize its nitrogen-fixing potential, genome sequence was obtained using PacBio RS II technology. The analyses of average nucleotide identity based on BLAST+ (ANIb) and correlation indexes of tetra-nucleotide signatures (Tetra) showed that the NF isolate GXGL-4A is closely related to the Kosakonia radicincitans type strain DSM 16656. Therefore, the isolate GXGL-4A was eventually classified into the species of Kosakonia radicincitans and designated K. radicincitans GXGL-4A. A high consistency in composition and gene arrangement of nitrogen-fixing gene cluster I (nif cluster I) was found between K. radicincitans GXGL-4A and other Kosakonia NF strains. The mutants tagged with green fluorescence protein (GFP) were obtained by transposon Tn5 mutagenesis, and then, the colonization of gfp-marked K. radicincitans GXGL-4A cells on cucumber seedling root were observed under fluorescence microscopy. The preferential sites of the labeled GXGL-4A cell population were the lateral root junctions, the differentiation zone, and the elongation zone. All these results should benefit for the deep exploration of nitrogen fixation mechanism of K. radicincitans GXGL-4A and will definitely facilitate the genetic modification process of this NF bacterium in sustainable agriculture.
3,6-Di(pyridin-2-yl)-1,2,4,5-tetrazine (pytz)-capped silver nanoparticles (TzAgNPs) inhibit biofilm formation of Pseudomonas aeruginosa : a potential approach toward breaking the wall of biofilm through reactive oxygen species (ROS) generation
Abstract
Microbial biofilms are factions of surface-colonized cells encompassed in a matrix of extracellular polymeric substances. Profound application of antibiotics in order to treat infections due to microbial biofilm has led to the emergence of several drug-resistant microbial strains. In this context, a novel type of 3,6-di(pyridin-2-yl)-1,2,4,5-tetrazine (pytz)-capped silver nanoparticles (TzAgNPs) was synthesized, and efforts were given to test its antimicrobial and antibiofilm activities against Pseudomonas aeruginosa, a widely used biofilm-forming pathogenic organism. The synthesized TzAgNPs showed considerable antimicrobial activity wherein the MIC value of TzAgNPs was found at 40 μg/mL against Pseudomonas aeruginosa. Antibiofilm activity of TzAgNPs was also tested against Pseudomonas aeruginosa by carrying out an array of experiments like microscopic observation, crystal violet assay, and protein count using the sub-MIC doses of TzAgNPs. Since TzAgNPs showed efficient antibiofilm activity, thus, in the present study, efforts were put together to investigate the underlying cause of biofilm attenuation of Pseudomonas aeruginosa by using TzAgNPs. To this end, we discerned that the sub-MIC doses of TzAgNPs increased ROS level considerably in the bacterial cell. The result showed that the ROS level and microbial biofilm formation are inversely proportional. Thus, the attenuation in microbial biofilm could be attributed to the accumulation of ROS level. Furthermore, it was also duly noted that microorganisms upon treatment with TzAgNPs exhibited considerable diminution in virulence factors (protease and pyocyanin) in contrast to the control where the organisms were not treated with TzAgNPs. Thus, the results indicated that TzAgNPs exhibit considerable reduction in the development of biofilms and spreading of virulence factors. Taken together, all the results indicated that TzAgNPs could be deemed to be a promising agent for the prevention of microbial biofilm development that might assist to fight against infections linked to biofilm.
Further characteristics of Arcanobacterium pinnipediorum DSM 28752 T and Arcanobacterium wilhelmae DSM 102162 T , two novel species of genus Arcanobacterium
Abstract
The newly described type strains Arcanobacterium pinnipediorum DSM 28752T and Arcanobacterium wilhelmae DSM 102162T, initially isolated from an anal swab of a harbor seal (Sammra et al. Int J Syst Evol Microbiol 65:4539–4543, 2015) and the genital tract of a rhinoceros (Sammra et al. Int J Syst Evol Microbiol 67:2093–2097, 2017), could be further characterized by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and Fourier transform infrared (FT-IR) spectroscopy and by sequencing the genomic targets 16S-23S rDNA intergenic spacer region (ISR) and the genes rpoB, gap, and tuf. The two strains investigated in the present study were isolated together with several other bacterial species indicating that the pathogenic importance of both species remained unclear. However, the detection of specific spectra by MALDI-TOF MS and by FT-IR spectroscopy and the presented genotypic approaches might help to identify A. pinnipediorum and A. wilhelmae in the future and might elucidate the role these two species play in infections of animals.
Rapid and simultaneous detection of Salmonella spp., Escherichia coli O157, and Listeria monocytogenes by magnetic capture hybridization and multiplex real-time PCR
Abstract
The application of rapid, specific, and sensitive methods for pathogen detection and quantification is very advantageous in diagnosis of human pathogens in several applications, including food analysis. The aim of this study was the evaluation of a method for the multiplexed detection and quantification of three significant foodborne pathogenic species (Escherichia coli O157, Salmonella spp., and Listeria monocytogenes). The assay combines specific DNA extraction by multiplex magnetic capture hybridization (mMCH) with multiplex real-time PCR. The amplification assay showed linearity in the range 106–10 genomic units (GU)/PCR for each co-amplified species. The sensitivity corresponded to 1 GU/PCR for E. coli O157 and L. monocytogenes, and 10 GU/PCR for Salmonella spp. The immobilization process and the hybrid capture of the MCH showed good efficiency and reproducibility for all targets, allowing the combination in equal amounts of the different nanoparticle types in mMCH. MCH and mMCH efficiencies were similar. The detection limit of the method was 10 CFU in samples with individual pathogens and 102 CFU in samples with combination of the three pathogens in unequal amounts (amount's differences of 2 or 3 log). In conclusion, this multiplex molecular platform can be applied to determine the presence of target species in food samples after culture enrichment. In this way, this method could be a time-saving and sensitive tool to be used in routine diagnosis.
KH-type splicing regulatory protein is regulated by nuclear factor-κB signaling to mediate innate immunity in Caco-2 cells infected by Salmonella enteritidis
Abstract
Salmonella enteritidis infection occurs in enterogenous diseases, such as gastroenteritis and parenteral focal infection, which often involve inflammation of intestinal epithelial cells. The nuclear factor kappa B (NF-κB) pathway participates in the innate immune response to many gram-negative pathogenic bacteria and initiates inflammation in epithelial cells. KH-type splicing regulatory protein (KSRP) is a multi-domain RNA-binding protein that recruits the exosome-containing mRNA degradation complex to mRNAs coding for inflammatory response factors. However, it remains unclear whether KSRP is regulated by NF-κB signaling pathway in response to S. enteritidis infection and affects the development of inflammation. Accordingly, in this study, we investigated the role of KSRP in mediating the response to S. enteritidis in Caco-2 cells. The data revealed that S. enteritidis infection decreased KSRP expression, which was suppressed by blocking the NF-κB pathway. Additionally, S. enteritidis infection significantly increased the expression of inducible nitric oxide synthase and cyclooxygenase-2. Overexpression of KSRP reduced the expression levels of inflammatory factors in Caco-2 cells. KSRP was regulated by the NF-κB signaling pathway and participated in mediating the innate immune response to S. enteritidis infection in Caco-2 cells, and KSRP acted as a negative regulator of inflammatory gene expression.
Production and cleavage of a fusion protein of porcine trypsinogen and enhanced green fluorescent protein (EGFP) in Pichia pastoris
Abstract
Pharmaceutical grade trypsin is in ever-increasing demand for medical and industrial applications. Improving the efficiency of existing biotechnological manufacturing processes is therefore paramount. When produced biotechnologically, trypsinogen—the inactive precursor of trypsin—is advantageous, since active trypsin would impair cell viability. To study factors affecting cell physiology and the production of trypsinogen in fed-batch cultures, we built a fusion protein of porcine trypsinogen and enhanced green fluorescent protein (EGFP) in Pichia pastoris. The experiments were performed with two different pH values (5.0 and 5.9) and two constant specific growth rates (0.02 and 0.04 1/h), maintained using exponential addition of methanol. All the productivity data presented rely on an active determination of trypsin obtained by proteolysis of the trypsinogen produced. The pH of the medium did not affect cell growth, but significantly influenced specific production of trypsinogen: A 1.7-fold higher concentration of trypsinogen was achieved at pH 5.9 (64 mg/L at 0.02 1/h) compared to pH 5.0. EGFP was primarily used to facilitate detection of intracellular protein over the biosynthetic time course. Using flow cytometry with fluorescence detection, cell disruption was avoided, and protein extraction and purification prior to analysis were unnecessary. However, Western blot and SDS-PAGE showed that cleavage of EGFP-trypsinogen fusion protein occurred, probably caused by Pichia-endogenous proteases. The fluorescence analysis did therefore not accurately represent the actual trypsinogen concentration. However, we gained new experimentally-relevant insights, which can be used to avoid misinterpretation of tracking and quantifying as well as online-monitoring of proteins with the frequently used fluorescent tags.
Local retrospective analysis of galactomannan cut-off values in bronchoalveolar lavage fluids for diagnosis of invasive aspergillosis
Abstract
Galactomannan antigen (GM) testing has been used for decades to screen immunocompromised patients for invasive aspergillosis (IA). Recent publications suggested that using a higher cut-off value than 0.5 in bronchoalveolar lavage fluid (BALF) could be more discriminant for hematology patients. We retrospectively analyzed the values of GM in BALF over 7 years (from 2010 to 2016). Performance indicators of the GM in BALF, according to three different cut-off values (0.5, 0.8, 1.5), were calculated using Stata 14.1. IA classification for hematology patients was based on European Organization for Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG) criteria, as defined in 2008. A number of 716 GM were performed on BALF from 2010 to 2016 (597 patients) and 66 were positive (> 0.5). Among these 597 patients, 27 IA were diagnosed, 13 with a positive GM in BALF, 9 with a negative GM in BALF, and 5 unclassified IA (ICU patients). The analysis of performance indicators, based on our local data, did not demonstrate any significant difference using a higher cut-off value of GM in BALF. This result may be explained by the local recruitment of patients and by pre-analytic variations during BALF realization.
Analysis of Streptomyces ghanaensis ATCC14672 gene SSFG_07725 for putative γ-butyrolactone synthase
Abstract
Low molecular weight signaling compounds (LMWC) are important players in regulating various aspects of Streptomyces biology. Their exact roles in certain strain will ultimately depend on overall configuration of regulatory network and thus cannot be predicted on basis of in silico studies. Here, we explored S. ghanaensis gene SSFG_07725 (afsAgh) presumably involved in initial steps of formation of γ-butyrolactone LMWC. Disruption of afsAgh impaired aerial mycelium formation and increased the transcription of pleiotropic regulatory gene adpAgh, whereas level of moenomycin production remained virtually unaffected. We provide evidence that morphogenetic deficiency of afsAgh-minus mutant was caused by inability to produce diffusible LMWC. Possible links between γ-butyrolactone signaling and various aspects of S. ghanaensis biology are discussed.
Yeast species diversity in apple juice for cider production evidenced by culture-based method
Abstract
Identification of yeasts isolated from apple juices of two cider houses (one located in a plain area and one in an alpine area) was carried out by culture-based method. Wallerstein Laboratory Nutrient Agar was used as medium for isolation and preliminary yeasts identification. A total of 20 species of yeasts belonging to ten different genera were identified using both BLAST algorithm for pairwise sequence comparison and phylogenetic approaches. A wide variety of non-Saccharomyces species was found. Interestingly, Candida railenensis, Candida cylindracea, Hanseniaspora meyeri, Hanseniaspora pseudoguilliermondii, and Metschnikowia sinensis were recovered for the first time in the yeast community of an apple environment. Phylogenetic analysis revealed a better resolution in identifying Metschnikowia and Moesziomyces isolates than comparative analysis using the GenBank or YeastIP gene databases. This study provides important data on yeast microbiota of apple juice and evidenced differences between two geographical cider production areas in terms of species composition.
Are zoonotic Staphylococcus pseudintermedius strains a growing threat for humans?
Abstract
Staphylococcus pseudintermedius is a species often isolated from animals, as a common element of their microbiota or an agent of infection, and from people associated with an animal habitat, including owners of home pets—dogs and cats. As with many other species, adaptation of these bacteria to the human body can occur, and they become important human pathogens. 59 S. pseudintermedius strains were investigated in this study to determine the factors contributing to human body colonization: inhibition growth of human skin residents isolated from human skin (Staphylococcus epidermidis, Corynebacterium spp., Cutibacterium acnes (formerly Propionibacterium acnes)), biofilm formation, and the presence of ten genes encoding infection-promoting features (including ebpS, spsE, lukS, lukF, pvl, lip, hlgA, hlgB). The ability of human skin to be colonized and the presence of genes that promote the development of skin infections showed the significant potential of the studied strains in their adaptation to the host. However, while a comparison of the characteristics of animal strains and those isolated from human infections does not allow us to claim that we are the witnesses of the speciation of a new human pathogen, it does indicate their gradual adaptation to the human organism.
Relation to enterocins of variable Aeromonas species isolated from trouts of Slovakian aquatic sources and detected by MALDI-TOF mass spectrometry
Abstract
Aeromonads represent bacteria thought to be primarily mostly autochthonous to aquatic environments. This study was focused on the relation with antibiotics and enterocins of identified Aeromonas species isolated from the intestine of trouts living in Slovakian aquatic sources. Intestinal samples from 50 trouts (3 Salmo trutta and 47 Salmo gairdnerii) were collected in April of years 2007, 2010, and 2015 from trouts of different water sources in Slovakia (pond Bukovec near Košice, river Čierny Váh). Due to the MALDI-TOF mass spectrometry evaluation, 25 strains were proposed to the genus Aeromonas involving nine different species (Aeromonas bestiarum—nine strains, Aer. salmonicida—four strains, Aer. encheleia, Aer. eucrenophila, Aer. molluscorum, Aer. media, Aer. sobria, Aer. popoffii, Aer. veronii). Phenotypic evaluation of individual strains confirmed their species identification. Twenty-five strains of different Aeromonas species were sensitive to azithromycin, amikacin, mecillinam, mezlocillin, piperacillin, gentamicin, chloramphenicol, and tetracycline. On the other side, they were resistant to carbenicillin and ticarcillin. The growth of Aer. bestiarum R41/1 was inhibited by treatment with Ent M and Ent 2019 (inhibition activity 100 AU/mL). Aer. bestiarum R47/3 was inhibited by eight enterocins (100 AU/mL). It is the first study testing enterocins to inhibit the growth of Aeromonas species from trouts.
MALDI-TOF MS Supplementary database for species identification employing the yeast diversity encountered on southern Brazil grapes
Abstract
The study of grape microflora is of interest when autochthonous yeasts, which are related to typical wine characteristics, are intended to be used in winemaking. The election of matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS) as the first method for yeast identification was based on its accuracy and rapidity compared to alternative laboratory protocols for identification. The aims of this study are to consolidate the MALDI-TOF MS Supplementary database for environmental yeasts already constructed, to expand it through the addition of standard spectra of not included yeast species, and to discuss the grape microflora encountered in Southern Brazil. A total of 358 strains, isolated from grape berries, were submitted to protein profiling employing Biotyper and Supplementary database. Molecular biology techniques were used as alternatives to identify 6.4% of strains not promptly designated by protein profiling. These strains corresponded to the species Candida californica, Zygoascus meyerae, Candida akabanensis, Candida azyma, and Hanseniaspora vineae. The MALDI-TOF MS spectra of the identified species were added to Supplementary database. The presented results strengthen the need for further expansion of the mass spectra database to broaden its microbiological application.
Bacterial DNA detected on pathologically changed heart valves using 16S rRNA gene amplification
Abstract
Nowadays, dental diseases are one of the most common illnesses in the world. Some of them can lead to translocation of oral bacteria to the bloodstream causing intermittent bacteraemia. Therefore, a potential association between oral infection and cardiovascular diseases has been discussed in recent years as a result of adhesion of oral microbes to the heart valves. The aim of this study was to detect oral bacteria on pathologically changed heart valves not caused by infective endocarditis. In the study, patients with pathologically changed heart valves were involved. Samples of heart valves removed during heart valve replacement surgery were cut into two parts. One aliquot was cultivated aerobically and anaerobically. Bacterial DNA was extracted using Ultra-Deep Microbiome Prep (Molzym GmbH, Bremen, Germany) followed by a 16S rRNA gene PCR amplification using Mastermix 16S Complete kit (Molzym GmbH, Bremen, Germany). Positive PCR products were sequenced and the sequences were analyzed using BLAST database (http://www.ncbi.nlm.nih/BLAST). During the study period, 41 samples were processed. Bacterial DNA of the following bacteria was detected in 21 samples: Cutibacterium acnes (formerly Propionibacterium acnes) (n = 11; 52.38% of patients with positive bacterial DNA detection), Staphylococcus sp. (n = 9; 42.86%), Streptococcus sp. (n = 1; 4.76%), Streptococcus sanguinis (n = 4; 19.05%), Streptococcus oralis (n = 1; 4.76%), Carnobacterium sp. (n = 1; 4.76%), Bacillus sp. (n = 2; 9.52%), and Bergeyella sp. (n = 1; 4.76%). In nine samples, multiple bacteria were found. Our results showed significant appearance of bacteria on pathologically changed heart valves in patients with no symptoms of infective endocarditis.
Metabolic reconstruction and experimental verification of glucose utilization in Desulfurococcus amylolyticus DSM 16532
Abstract
Desulfurococcus amylolyticus DSM 16532 is an anaerobic and hyperthermophilic crenarchaeon known to grow on a variety of different carbon sources, including monosaccharides and polysaccharides. Furthermore, D. amylolyticus is one of the few archaea that are known to be able to grow on cellulose. Here, we present the metabolic reconstruction of D. amylolyticus' central carbon metabolism. Based on the published genome, the metabolic reconstruction was completed by integrating complementary information available from the KEGG, BRENDA, UniProt, NCBI, and PFAM databases, as well as from available literature. The genomic analysis of D. amylolyticus revealed genes for both the classical and the archaeal version of the Embden-Meyerhof pathway. The metabolic reconstruction highlighted gaps in carbon dioxide-fixation pathways. No complete carbon dioxide-fixation pathway such as the reductive citrate cycle or the dicarboxylate-4-hydroxybutyrate cycle could be identified. However, the metabolic reconstruction indicated that D. amylolyticus harbors all genes necessary for glucose metabolization. Closed batch experimental verification of glucose utilization by D. amylolyticus was performed in chemically defined medium. The findings from in silico analyses and from growth experiments are discussed with respect to physiological features of hyperthermophilic organisms.
The heterologous expression potential of an acid-tolerant Talaromyces pinophilus β-glucosidase in Saccharomyces cerevisiae
Abstract
A filamentous fungus displaying high cellulase activity was isolated from a compost heap with triticale (a wheat-rye hybrid) as the main constituent. It was preliminarily identified as a Talaromyces pinophilus species. A 2577 base pair β-glucosidase gene was cloned from complementary DNA and heterologously expressed in Saccharomyces cerevisiae. The recombinant β-glucosidase production profile was assessed and compared to that of the Saccharomycopsis fibuligera β-glucosidase which served as a benchmark. The enzyme was also characterised in terms of pH and temperature tolerance as well as response to inhibitors. Maximal extracellular β-glucosidase activity of 0.56 nkat/mg total protein was measured using p-nitrophenyl-β-D-glucopyranoside as substrate. The recombinant protein displayed a pH optimum of 4.0, and good thermostability as 70% of maximal enzyme activity was retained after 1 h at 60 °C. Activity of the recombinant β-glucosidase was adversely affected by the presence of glucose and ethanol at higher concentrations while xylose had no effect. The expression of the T. pinophilus β-glucosidase did not reach the same titres as for the benchmark; however, in the context of constructing a yeast strain for bioethanol production in a consolidated bioprocess, the enzyme may still show good potential.
Management of the Platysma in Neck Lift
Traditional techniques to treat platysma bands relied on corset tightening of the anterior platysma muscle borders or rigid suspension of the lateral platysma borders to sternocleidomastoid or periauricular fascia. Although results seemed good, recurrence was common and the ultimate outcome was poor. Despite modifications, they have largely failed, and for surgeons seeking to rejuvenate the face, treating platysma bands remains a most frustrating and perplexing problem in neck surgery. However, if problems are understood and carefully defined, and logical plans are used to treat them, significant improvement in common neck problems related to the platysma muscles can be obtained.
Short Scar Neck Lift
For a subset of patients poor neck contour exists as a largely isolated problem and can be treated with a short scar neck lift procedure whereby no skin is removed. The procedure is performed through a submental incision without any removal of skin and relies on modification of deep-layer structures to improve neck contour. "Excess" skin is allowed to redistribute itself over the increased neck surface area created when deep-layer maneuvers are performed, neck contour is improved, and the cervicomental angle deepened. For properly selected patients, the procedure can produce a marked improvement in facial appearance.
Extended Deep Plane Facelift
This article describes our extended, deep plane facelift technique. This procedure releases 4 key retaining ligaments in the face and neck, the zygomatic cutaneous, masseteric cutaneous, mandibular cutaneous, and cervical retaining ligaments. Once released, the composite deep plane flap is repositioned to volumize the midface and gonial angle. Important anatomic considerations during deep plane dissection are discussed. In the neck, focus is on extending the deep plane dissection of the platysma, releasing the cervical retaining ligaments, creating a platysmal hammock to support the submandibular gland, defining the inferior mandibular contour, and minimizing the need to open the neck.
Neck Lift
Success or failure in treating the neck lies in the diagnosis of underlying problems and the application of a logical surgical plan. Although it is a commonly advocated practice, it is not enough to perform submental liposuction and tighten the skin in most patients, as such an approach ignores a number of anatomic problems present in many patients seeking neck improvement. Removing subcutaneous fat and tightening skin over these problems does not correct them, and the presence or absence of each must be looked for to create and apply an appropriate surgical plan.
Lower Facial Rejuvenation
Traditionally, when facial rejuvenation was discussed, the face would receive the majority of the attention. Over the last decade, it has increasingly recognized that, in most cases without excellent concomitant neck rejuvenation, the overall result of a face–neck-lift will be average rather than superb. In fact, some authors would argue that the highest yield in satisfaction is provided by an excellent result in the neck component of the facial rejuvenation. The motifs in neck rejuvenation have also changed over the years, similarly to the face, but lagging by several decades.
Large pseudoencapsulated subcutaneous angiomyxoma: Surgical management
Superficial angiomyxoma is a rare benign skin tumor of mesenchymal origin composed of a myxoid matrix, thin-walled blood vessels, and sparse small spindle cells. This tumor is reported to have a high local recurrence rate when excised, possibly because muscle and soft tissue infiltration can occur. Thus, the term superficial can be misleading. In one published series, the local recurrence rate was 36%1 and in another 38%.2 However, all reported series are pathologic studies in which details of surgical excisions are scant.
Lichen planopilaris with Koebner phenomenon
Lichen planopilaris (LLP) is a rare, progressive disease of the scalp and is an important cause of scarring alopecia.1 LPP is classified clinically into 3 types: classic LPP, frontal fibrosing alopecia, and Graham-Little-Piccardi-Lassueur syndrome.2,3 In classic LPP, patients commonly present with single or multiple patches of alopecia in the vertex of the scalp.4 The exact pathogenesis of LPP remains unclear.5,6 Here we describe a case involving one of the youngest reported adult subjects in which the trigger for LPP is unique and was not previously reported.
Recalcitrant annular pustular psoriasis associated with psoriatic arthritis successfully treated with secukinumab
Pustular psoriasis is a well-known form of psoriasis, the main variants of which are acute generalized pustular psoriasis (GPP), including GPP of pregnancy, annular pustular psoriasis (APP), acrodermatitis continua of Hallopeau (ACH), and palmoplantar pustulosis (PPP). APP is a rare entity that presents as recurring annular or figurate erythematous plaques with peripheral pustules and scales that expand centrifugally.
Treatment of psoriasis vulgaris using low-dose naltrexone
Psoriasis is a common, immune-mediated skin disease affecting 3.1% of the US population.1 Psoriasis negatively impacts health-related quality of life and is associated with multiple physical and mental health comorbidities2 in addition to symptoms such as pain, itching, and bleeding. Psoriasis also imparts substantial burden on the national economy, including high health care resource use and direct and indirect costs and contributes to work impairment, presenteeism, and employment status changes because of symptoms.
55-year-old man with ulcers in inguinal fold and intergluteal cleft found to have systemic Langerhans cell histiocytosis
This article describes the case of a patient with cutaneous ulcers who was found to have systemic Langerhans cell histiocytosis (LCH). This article includes the clinical, histology, and electron microscopy images, in addition to a description of the presentation, workup, and management of this rare disease in this patients, with a review of the literature.
Group C streptococcal cellulitis, looking deeper than the skin
Group C streptococci (GCS), predominantly Streptococcus dysgalactiae subspecies equisimilis in humans, are gram-positive, ß-hemolytic bacteria that form part of the normal oral flora and may be seen in cases of pharyngitis and cellulitis. In a review of 88 patients with GCS bacteremia, infections commonly originated from the upper respiratory tract (20.5%), gastrointestinal tract (18.2%), or the skin (17.1%).1 GCS has also been reported in septic arthritis, endocarditis, meningitis, pneumonia, necrotizing fasciitis, and toxic shock–like syndrome.
Dermoscopy of eccrine angiomatous hamartoma: The spitzoid pattern
A 5-year old girl presented with an erythematous, asymptomatic nodule of the left knee, which appeared 1 year before (Fig 1).
Rare presentation of erythema elevatum diutinum
Erythema elevatum diutinum (EED) is a rare, chronic, and progressive skin condition, classified within the neutrophilic vasculitides. It presents as erythematous and violaceus papules and plaques. The distribution tends to be bilateral and symmetrical, overlying joints and localized on extensor surfaces. EED generally affects middle-age patients. Although its cause is yet unknown, it can be associated with other underlying autoimmune, infectious, or malignant diseases. Dapsone is used as a first-line therapeutic agent.
Persistent injection site nodules from exenatide: Successful treatment with intralesional triamcinolone
Exenatide extended release is a once-weekly injectable medication used for the treatment of type II diabetes mellitus. The long-acting formulation consists of the original twice-daily formulation encapsulated in 0.06-mm-diameter microspheres.1 The subcutaneously injected exenatide microspheres then diffuse the medication slowly over time, reaching therapeutic range by 2 weeks and steady state by 6 to 7 weeks.1 Pharmacologically, it acts as an incretin analogue that activates glucagonlike peptide 1 receptors causing a glucose-dependent insulin secretion.
Madelung lipomatosis presenting as a manifestation of myoclonic epilepsy with ragged red fibers (MERRF) syndrome
This is a unique case of a patient with a history of myoclonic epilepsy with ragged red fibers (MERRF) syndrome presenting with Madelung or multiple symmetric lipomatosis. We discuss the etiology of MERRF syndrome and its link with Madelung lipomatosis via a common mitochondrial mutation that can be present in both diseases. The appearance of Madelung lipomatosis should prompt physicians to search for other neural, muscular, and pulmonary findings that may lead to a diagnosis of MERRF syndrome.
Certolizumab in a patient with severe psoriasis and concomitant hepatitis C virus infection
The treatment of psoriasis has benefited in recent years from the introduction of biological drugs that target specific components of the immune system. Some of these drugs block the excess production of tumor necrosis factor (TNF)-α in the skin or joints, thus, helping stop the inflammatory cycle of psoriatic disease. However, it has been suggested that anti–TNF-α agents could be associated with exacerbations of concomitant viral infections, an effect that could have potentially serious consequences in patients with hepatitis C virus (HCV) infection.
Reply: Commentary on letter to the editor from Drago et al
To the Editor: We appreciate the opportunity to respond to the letter by Drago et al, regarding our recently published report, "Ibrutinib-associated pityriasis rosea-like rash."1
Removal notice
Removal notice to "Severe recalcitrant cutaneous eruption with dual immune checkpoint blockade"
Granulomatous dermatitis as a postherpetic isotopic response in immunocompromised patients: A report of 5 cases
Granulomatous dermatitis (GD) describes disorders in which mixed inflammatory infiltrates composed primarily of histiocytes invade the skin. The pathogenesis of GD is unknown; however, GD has been noted to occur in areas previously affected by trauma, sun damage, or infection.1 When GD presents at the same site of a healed, unrelated skin disease, it falls within the category of a Wolf's isotopic response.2 The regional restriction of a Wolf's isotopic response is proposed to occur due to an area of localized immunocompromise known as an immunocompromised district.
Superficial granulomatous pyoderma of the leg improved after conservative management with Unna boot and intralesional steroid injections
Superficial granulomatous pyoderma (SGP) is a rare condition that some regard as a variant of pyoderma gangrenosum (PG) given their clinical similarities; however, SGP is distinct in its cutaneous presentation, histology, lack of underlying disease, and prognosis. Treatment options have ranged from oral antibiotics to oral and intralesional steroids, immunomodulatory agents, and intravenous immunoglobulin (IVIG), among others. We describe a case of long-standing SGP that responded to conservative management with Unna boot and intralesional steroid injections.
Successful treatment of type I pityriasis rubra pilaris with ixekizumab
Pityriasis rubra pilaris (PRP) is a rare condition that has been classified into 6 subtypes dependent on morphologic features, prognosis, age of onset, and HIV status.1,2 Classic adult subtype I accounts for approximately 55% of cases. It is clinically characterized by diffuse follicular plugging and perifollicular erythema coalescing to form orange-red scaly plaques with follicular plugging extending caudally to form generalized erythema with characteristic small islands of normal-appearing skin.
Palisaded neutrophilic and granulomatous dermatitis associated with ledipasvir/sofosbuvir
Palisaded neutrophilic and granulomatous dermatitis (PNGD) is a cutaneous reaction pattern seen in association with systemic diseases and rarely with infections or medications.1 Typical clinical presentation includes tender, erythematous-to-violaceous papules, plaques, or nodules affecting extensor and acral surfaces, most commonly the elbows and hands.1,2 Histopathologic examination of the lesions can vary, and the disease is thought to occur along a continuum, with early lesions histologically resembling leukocytoclastic vasculitis with dense neutrophilic infiltration and more established lesions consisting of palisaded histiocytes and small granulomas with trapping of collagen and neutrophilic debris.
Acquired epidermodysplasia verruciformis in setting of tumor necrosis factor-α inhibitor therapy
Epidermodysplasia verruciformis (EV) is a rare dermatologic condition in which patients have recalcitrant lesions associated with specific human papillomavirus (HPV) types. More than 20 types of HPV are associated with EV (termed EV-HPV types) and most commonly include HPV 5 and 8.1-3 First described as a genodermatosis, it has more recently been reported as an acquired form in patients with an underlying source of immunosuppression, namely, HIV.2 It has not been reported in patients on tumor necrosis factor (TNF)-α inhibitors.
Medium-vessel vasculitis presenting as multiple leg ulcers after treatment with abatacept
Abatacept (Orencia) is a recombinant fusion protein of cytotoxic T-lymphocyte–associated antigen-4 and human immunoglobulin that inhibits T-cell activation and proliferation by binding to CD80 and CD86 on antigen-presenting cells and prevents binding to CD28 on T cells.1 The drug is approved by the US Food and Drug Administration to treat adult rheumatoid arthritis, juvenile idiopathic arthritis, and, more recently, psoriatic arthritis.
Generalizations, Cultural Essentialism, and Metaphorical Gulfs
Abstract
An ongoing debate in comparative research is about whether we should see cultural diversities as manifestations of essential differences or as superficial variations on a universal blueprint. Edward Slingerland has pointed to cognitive science and the use of embodied metaphors to emphasize the universality of concept formation and cognition across cultures. He suggests that this should quiet the "cultural essentialists" who take fundamental differences in Eastern and Western thinking as their starting points. Michael Puett has also leveled a critique of cultural essentialism in support of a presuppositionless approach, and Slingerland's conclusions seem to offer him support. However, I will argue that even if all modern humans are broadly similar in metaphor use and cognitive processes, research in the humanities must continue to account for the differences implied by the particular metaphors employed and emphasized in diverse traditions. I contend that responsible hermeneutic practice does this through provisional, yet indispensable, generalizations.
Results of a nationwide epidemiologic survey of autosomal recessive congenital ichthyosis and ichthyosis syndromes in Japan
Autosomal recessive congenital ichthyosis (ARCI) and ichthyosis syndrome (IS) are rare genetic skin disorders.
Follicular Involvement is Frequent in Lentigo Maligna: Implications for Treatment
Follicular involvement is a characteristic of lentigo maligna (LM) with unknown frequency. 95.8% of LM specimens demonstrated intrafollicular lesional melanocytes, with a mean depth of 0.45mm. When managing LM, follicular involvement should be assumed.
Laser-assisted photodynamic therapy for actinic keratosis: A systematic review and meta-analysis
This meta-analysis suggests that photodynamic therapy combined with ablative laser treatment for actinic keratosis is more efficient but not more painful than either therapy alone. Laser-assisted photodynamic therapy is an attractive option for patients with multiple actinic keratoses or field cancerization
The Infraorbital Artery: Clinical Relevance in Esthetic Medicine and Identification of Danger Zones of the midface
Over the past decade, cosmetic injections of dermal fillers or fat have become a popular procedure in facial rejuvenation in an overconsuming society. However, complications such as arterial embolism and occlusion can occur even with experienced injectors, especially in high-risks zones namely the glabella, the nasal dorsum or the nasolabial fold. The aim of this study was to define the vascular danger zones of the infraorbital area in order to provide guidelines helping avoid them.
Guideline on the use of onabotulinumtoxinA in chronic migraine: a consensus statement from the European Headache Federation
OnabotulinumtoxinA is being increasingly used in the management of chronic migraine (CM). Treatment with onabotulinumtoxinA poses challenges compared with traditional therapy with orally administered preventat...
A Content Analysis of Local Media Framing of Intimate Partner Violence
Violence and Gender, Ahead of Print.
Juvenile Spring Eruption Associated With Parvovirus B19 Infection
This case report describes the occurrence of juvenile spring eruption associated with parvovirus B19 infection.
Multispectral Optoacoustic Tomography for Vascular Malformations
This pilot study evaluates the use of multispectral optoacoustic tomography for assessment of biomarkers among patients with arteriovenous and venous malformation.
Differences in Use of Outpatient Dermatology Services in the United States
This study examines nationwide differences in demographic and socioeconomic characteristics and use of outpatient dermatologic care among Medical Expenditure Panel Survey respondents.
Vasculitis
This Patient Page describes vasculitis, focusing especially on skin vasculitis, how to recognize it, and how it might be treated.
Increased Synthesis of Chondroitin Sulfate Proteoglycan Promotes Adult Hippocampal Neurogenesis in Response to Enriched Environment
Chondroitin sulfate proteoglycan (CSPG) is a candidate regulator of embryonic neurogenesis. The aim of this study was to specify the functional significance of CSPG in adult hippocampal neurogenesis using male mice. Here, we showed that neural stem cells and neuronal progenitors in the dentate gyrus were covered in part by CSPG. Pharmacological depletion of CSPG in the dentate gyrus reduced the densities of neuronal progenitors and newborn granule cells. 3D reconstruction of newborn granule cells showed that their maturation was inhibited by CSPG digestion. The novel object recognition test revealed that CSPG digestion caused cognitive memory impairment. Western blot analysis showed that expression of β-catenin in the dentate gyrus was decreased by CSPG digestion. The amount of CSPG in the dentate gyrus was increased by enriched environment (EE) and was decreased by forced swim stress. In addition, EE accelerated the recovery of CSPG expression in the dentate gyrus from the pharmacological depletion and promoted the restoration of granule cell production. Conversely, the densities of newborn granule cells were also decreased in mice that lacked chondroitin sulfate N-acetylgalactosaminyltransferase 1 (CSGalNAcT1), a key enzyme for CSPG synthesis (T1KO mice). The capacity of EE to promote granule cell production and improve cognitive memory was impaired in T1KO mice. These findings indicate that CSPG is involved in the regulation of adult hippocampal neurogenesis and suggest that increased synthesis of CSPG by CSGalNacT1 may mediate promotion of granule cell production and improvement of cognitive memory in response to EE.
SIGNIFICANCE STATEMENT Chondroitin sulfate proteoglycan (CSPG) is a candidate regulator of embryonic neurogenesis. Here, we specified the role of CSPG in adult neurogenesis in the mouse hippocampus. Digestion of CSPG in the dentate gyrus impaired granule cell production and cognitive memory. Enriched environment (EE) promoted the recovery of CSPG expression and granule cell production from the CSPG digestion. Additionally, adult neurogenesis was impaired in mice that lacked a key enzyme for CSPG synthesis (T1KO mice). The capacity of EE to promote granule cell production and cognitive memory was impaired in T1KO mice. Altogether, these findings indicate that CSPG underlies adult hippocampal neurogenesis and suggest that increased synthesis of CSPG may mediate promotion of granule cell production in response to EE.
Coherent Activity between the Prelimbic and Auditory Cortex in the Slow-Gamma Band Underlies Fear Discrimination
The medial prefrontal cortex and the basolateral amygdala (BLA) are essential for discriminating between harmful and safe stimuli. The primary auditory cortex (Te1) sends projections to both sites, but whether and how it interacts with these areas during fear discrimination are poorly understood. Here we show that in male rats that can differentiate between a new tone and a threatening one, the selective optogenetic inhibition of Te1 axon terminals into the prelimbic (PL) cortex shifted discrimination to fear generalization. Meanwhile, no effects were detected when Te1 terminals were inhibited in the BLA. Using a combination of local field potential and multiunit recordings, we show that in animals that discriminate successfully between a new tone and a harmful one, the activity of the Te1 and the PL cortex becomes immediately and tightly synchronized in the slow-gamma range (40–70 Hz) at the onset of the new tone. This enhanced synchronization was not present in other frequency ranges, such as the theta range. Critically, the level of gamma synchrony predicted the behavioral choice (i.e., no freezing or freezing) of the animals. Moreover, in the same rats, gamma synchrony was absent before the fear-learning trial and when animals should discriminate between an olfactory stimulus and the auditory harmful one. Thus, our findings reveal that the Te1 and the PL cortex dynamically establish a functional connection during auditory fear-discrimination processes, and that this corticocortical oscillatory mechanism drives the behavioral choice of the animals.
SIGNIFICANCE STATEMENT Identifying neural networks that infer safety versus danger is of great interest in the scientific field. Fear generalization reduces the chances of an animal's survival and leads to psychiatric diseases, such as post-traumatic stress disorders and phobias in humans. Here we demonstrate that animals able to differentiate a new tone from a previous threating tone showed synchronization between the prefrontal and primary auditory cortices. Critically, this connectivity precedes and predicts the behavioral outcome of the animal. Optogenetic inhibition of this functional connectivity leads to fear generalization. To the best of our knowledge, this study is the first to demonstrate that a corticocortical dialogue occurring between sensory and prefrontal areas is a key node for fear-discrimination processes.
Feedback-Based Learning in Aging: Contributions and Trajectories of Change in Striatal and Hippocampal Systems
The striatum supports learning from immediate feedback by coding prediction errors (PEs), whereas the hippocampus (HC) plays a parallel role in learning from delayed feedback. Both regions show evidence of decline in human aging, but behavioral research suggests greater decline in HC versus striatal functions. The present study included male and female humans and used fMRI to examine younger and older adults' brain activation patterns during a learning task with choice feedback presented immediately or after a brief delay. Participants then completed a surprise memory task that tested their recognition of trial-unique feedback stimuli, followed by assessments of postlearning cue preference, outcome probability awareness, and willingness to pay. The study yielded three main findings. First, behavioral measures indicated similar rates of learning in younger and older adults across conditions, but postlearning measures indicated impairment in older adults' ability to subsequently apply learning to discriminate between cues. Second, PE signals in the striatum were greater for immediate versus delayed feedback in both age groups, but PE signals in the HC were greater for delayed versus immediate feedback only in younger adults. Third, unlike younger adults, older adults failed to exhibit enhanced episodic memory for outcome stimuli in the delayed-feedback condition. Together, these findings indicate that HC circuits supporting learning and memory decline more than striatal circuits in healthy aging, which suggests that declines in HC learning signals may be an important predictor of deficits in learning-dependent economic decisions among older adults.
SIGNIFICANCE STATEMENT The hippocampus (HC) and striatum play distinct and critical roles in learning. Substantial research suggests that age-related decline in learning supported by the HC outpaces decline in learning supported by the striatum; however, such inferences have been drawn by comparing performance in tasks with fundamentally different structures. The present study overcomes this obstacle by implementing a single fMRI-learning paradigm with a subtle variation in feedback timing to examine differential age effects on memory supported by the HC and striatum. Our results provide converging behavioral and brain-imaging evidence showing that HC circuits supporting learning and memory decline more than striatal circuits in healthy aging and that declines in HC learning signals may predict early deficits in learning-dependent decisions among older adults.
Transneuronal Downregulation of the Premotor Cholinergic System After Corticospinal Tract Loss
Injury to the supraspinal motor systems, especially the corticospinal tract, leads to movement impairments. In addition to direct disruption of descending motor pathways, spinal motor circuits that are distant to and not directly damaged by the lesion undergo remodeling that contributes significantly to the impairments. Knowing which spinal circuits are remodeled and the underlying mechanisms are critical for understanding the functional changes in the motor pathway and for developing repair strategies. Here, we target spinal premotor cholinergic interneurons (IN) that directly modulate motoneuron excitability via their cholinergic C-bouton terminals. Using a model of unilateral medullary corticospinal tract lesion in male rats, we found transneuronal downregulation of the premotor cholinergic pathway. Phagocytic microglial cells were upregulated in parallel with cholinergic pathway downregulation and both were blocked by minocycline, a microglia activation inhibitor. Additionally, we found a transient increase in interneuronal complement protein C1q expression that preceded cell loss. 3D reconstructions showed ongoing phagocytosis of C1q-expressing cholinergic INs by microglia 3 d after injury, which was complete by 10 d after injury. Unilateral motor cortex inactivation using the GABAA receptor agonist muscimol replicated the changes detected at 3 d after lesion, indicating activity dependence. The neuronal loss after the lesion was rescued by increasing spinal activity using cathodal trans-spinal direct current stimulation. Our finding of activity-dependent modulation of cholinergic premotor INs after CST injury provides the mechanistic insight that maintaining activity, possibly during a critical period, helps to protect distant motor circuits from further damage and, as a result, may improve motor functional recovery and rehabilitation.
SIGNIFICANCE STATEMENT Supraspinal injury to the motor system disrupts descending motor pathways, leading to movement impairments. Whether and how intrinsic spinal circuits are remodeled after a brain injury is unclear. Using a rat model of unilateral corticospinal tract lesion in the medulla, we show activity-dependent, transneuronal downregulation of the spinal premotor cholinergic system, which is mediated by microglial phagocytosis, possibly involving a rapid and transient increase in neuronal C1q before neuronal loss. Spinal cord neuromodulation after injury to augment spinal activity rescued the premotor cholinergic system. Our findings provide the mechanistic insight that maintaining activity, possibly during an early critical period, could protect distant motor circuits from further damage mediated by microglia and interneuronal complement protein and improve motor functional outcomes.
Contextual-Dependent Attention Effect on Crowded Orientation Signals in Human Visual Cortex
A target becomes hard to identify with nearby visual stimuli. This phenomenon, known as crowding, places a fundamental limit on conscious perception and object recognition. To understand the neural representation of crowded stimuli, we used fMRI and a forward encoding model to reconstruct the target-specific feature from multivoxel activation patterns evoked by orientation patches. Orientation-selective response profiles were constructed in V1–V4 for a target embedded in different contexts. Subjects of both sexes either directed their attention over all the orientation patches or selectively to the target. In the context with a weak crowding effect, attending to the target enhanced the orientation selectivity of the response profile; such effect increased along the visual pathway. In the context with a strong crowding effect, attending to the target enhanced the orientation selectivity of the response profile in the earlier visual area, but not in V4. The increase and decrease of orientation selectivity along the visual hierarchy demonstrate a contextual-dependent attention effect on crowded orientation signals: in the context with a weak crowding effect, selective attention gradually resolves the target from nearby distractors along the hierarchy; in the context with a strong crowding effect, while selective attention maintains the target feature in the earlier visual area, its effect decreases in the downstream area. Our findings reveal how the human visual system represents the target-specific feature at multiple stages under the limit of attention selection in a cluttered scene.
SIGNIFICANCE STATEMENT Using fMRI and a forward encoding model, we reconstructed orientation-selective response profiles for a target embedded in crowded contexts. In the context with a weak crowding effect, attention gradually resolves the target from nearby distractors along the visual hierarchy. In the context with a strong crowding effect, while the feature of the target is preserved in the early visual cortex, it degrades in the later visual processing stage. The increase and decrease of orientation selectivity along the visual hierarchy reveal how the human visual system strikes to present the target-specific feature under the limit of attention selection in a cluttered scene.
Protein Tyrosine Phosphatase Receptor Type J (PTPRJ) Regulates Retinal Axonal Projections by Inhibiting Eph and Abl Kinases in Mice
Eph receptors play pivotal roles in the axon guidance of retinal ganglion cells (RGCs) at the optic chiasm and the establishment of the topographic retinocollicular map. We previously demonstrated that protein tyrosine phosphatase receptor type O (PTPRO) is specifically involved in the control of retinotectal projections in chicks through the dephosphorylation of EphA and EphB receptors. We subsequently revealed that all the mouse R3 subfamily members (PTPRB, PTPRH, PTPRJ, and PTPRO) of the receptor protein tyrosine phosphatase (RPTP) family inhibited Eph receptors as their substrates in cultured mammalian cells. We herein investigated the functional roles of R3 RPTPs in the projection of mouse retinal axon of both sexes. Ptpro and Ptprj were expressed in mouse RGCs; however, Ptprj expression levels were markedly higher than those of Ptpro. Consistent with their expression levels, Eph receptor activity was significantly enhanced in Ptprj-knock-out (Ptprj-KO) retinas. In Ptprj-KO and Ptprj/Ptpro-double-KO (DKO) mice, the number of retinal axons that projected ipsilaterally or to the contralateral eye was significantly increased. Furthermore, retinal axons in Ptprj-KO and DKO mice formed anteriorly shifted ectopic terminal zones in the superior colliculus (SC). We found that c-Abl (Abelson tyrosine kinase) was downstream of ephrin–Eph signaling for the repulsion of retinal axons at the optic chiasm and in the SC. c-Abl was identified as a novel substrate for PTPRJ and PTPRO, and the phosphorylation of c-Abl was upregulated in Ptprj-KO and DKO retinas. Thus, PTPRJ regulates retinocollicular projections in mice by controlling the activity of Eph and c-Abl kinases.
SIGNIFICANCE STATEMENT Correct retinocollicular projection is a prerequisite for proper vision. Eph receptors have been implicated in retinal axon guidance at the optic chiasm and the establishment of the topographic retinocollicular map. We herein demonstrated that protein tyrosine phosphatase receptor type J (PTPRJ) regulated retinal axonal projections by controlling Eph activities. The retinas of Ptprj-knock-out (KO) and Ptpro/Ptprj double-KO mice exhibited significantly enhanced Eph activities over those in wild-type mice, and their axons showed defects in pathfinding at the chiasm and retinocollicular topographic map formation. We also revealed that c-Abl (Abelson tyrosine kinase) downstream of Eph receptors was regulated by PTPRJ. These results indicate that the regulation of the ephrin–Eph–c-Abl axis by PTPRJ plays pivotal roles in the proper central projection of retinal axons during development.
A Brain-Heart Biomarker for Epileptogenesis
Postinjury epilepsy is an potentially preventable sequela in as many as 20% of patients with brain insults. For these cases biomarkers of epileptogenesis are critical to facilitate identification of patients at high-risk of developing epilepsy and to introduce effective anti-epileptogenic interventions. Here, we demonstrate that delayed brain–heart coincidences serve as a reliable biomarker. In a murine model of post-infection acquired epilepsy, we used long-term simultaneous measurements of the brain activity via electroencephalography and autonomic cardiac activity via electrocardiography, in male mice, to quantitatively track brain–heart interactions during epileptogenesis. We find that abnormal cortical discharges precede abnormal fluctuations in the cardiac rhythm at the resolution of single beat-to-beat intervals. The delayed brain–heart coincidence is detectable as early as the onset of chronic measurements, 2–14 weeks before the first seizure, only in animals that become epileptic, and increases during epileptogenesis. Therefore, delayed brain–heart coincidence serves as a biomarker of epileptogenesis and could be used for phenotyping, diagnostic, and therapeutic purposes.
SIGNIFICANCE STATEMENT No biomarker that readily predicts and tracks epileptogenesis currently exists for the wide range of human acquired epilepsies. Here, we used long-term measurements of brain and heart activity in a mouse model of post-infection acquired epilepsy to investigate the potential of brain–heart interaction as a biomarker of epileptogenesis. We found that delayed coincidences from brain to heart can clearly separate the mice that became epileptic from those that did not weeks before development of epilepsy. Our findings allow for phenotyping and tracking of epileptogenesis in this and likely other models of acquired epilepsy. Such capability is critical for efficient adjunctive treatment development and for tracking the efficacy of such treatments.
S-Nitrosylation of Divalent Metal Transporter 1 Enhances Iron Uptake to Mediate Loss of Dopaminergic Neurons and Motoric Deficit
Elevated iron deposition has been reported in Parkinson's disease (PD). However, the route of iron uptake leading to high deposition in the substantia nigra is unresolved. Here, we show a mechanism in enhanced Fe2+ uptake via S-nitrosylation of divalent metal transporter 1 (DMT1). While DMT1 could be S-nitrosylated by exogenous nitric oxide donors, in human PD brains, endogenously S-nitrosylated DMT1 was detected in postmortem substantia nigra. Patch-clamp electrophysiological recordings and iron uptake assays confirmed increased Mn2+ or Fe2+ uptake through S-nitrosylated DMT1. We identified two major S-nitrosylation sites, C23 and C540, by mass spectrometry, and DMT1 C23A or C540A substitutions abolished nitric oxide (NO)-mediated DMT1 current increase. To evaluate in vivo significance, lipopolysaccharide (LPS) was stereotaxically injected into the substantia nigra of female and male mice to induce inflammation and production of NO. The intranigral LPS injection resulted in corresponding increase in Fe2+ deposition, JNK activation, dopaminergic neuronal loss and deficit in motoric activity, and these were rescued by the NO synthase inhibitor l-NAME or by the DMT1-selective blocker ebselen. Lentiviral knockdown of DMT1 abolished LPS-induced dopaminergic neuron loss.
SIGNIFICANCE STATEMENT Neuroinflammation and high cytoplasmic Fe2+ levels have been implicated in the initiation and progression of neurodegenerative diseases. Here, we report the unexpected enhancement of the functional activity of transmembrane divalent metal transporter 1 (DMT1) by S-nitrosylation. We demonstrated that S-nitrosylation increased DMT1-mediated Fe2+ uptake, and two cysteines were identified by mass spectrometry to be the sites for S-nitrosylation and for enhanced iron uptake. One conceptual advance is that while DMT1 activity could be increased by external acidification because the gating of the DMT1 transporter is proton motive, we discovered that DMT1 activity could also be enhanced by S-nitrosylation. Significantly, lipopolysaccharide-induced nitric oxide (NO)-mediated neuronal death in the substantia nigra could be ameliorated by using l-NAME, a NO synthase inhibitor, or by ebselen, a DMT1-selective blocker.
Posterior Parietal Cortex Dysfunction Is Central to Working Memory Storage and Broad Cognitive Deficits in Schizophrenia
PFC dysfunction is widely believed to underlie working memory (WM) deficits in people with schizophrenia (PSZ), but few studies have focused on measures of WM storage devoid of manipulation. Research in neurotypical individuals has shown that storage capacity is more closely related to posterior parietal cortex (PPC) than PFC, suggesting that reductions in WM storage capacity in schizophrenia that are associated with broad cognitive deficits may be related to neural activity in PPC. In the present human neuroimaging study, 37 PSZ and 37 matched healthy control subjects of either sex completed a change detection task with varying set sizes while undergoing fMRI. The task was designed to emphasize WM storage with minimal top-down control demands. Whole-brain analysis identified areas in which BOLD activity covaried with the number of items maintained in WM (K), as derived from task performance at a given set size. Across groups, K values independent of set size predicted BOLD activity in PPC, including superior and inferior parietal lobules and intraparietal sulcus, and middle occipital gyrus. Whole-brain interaction analysis found significantly less K-dependent signal modulation in PSZ than healthy control subjects in left PPC, a phenomenon that could not be explained by a narrower K value range. The slope between K and PPC activation statistically accounted for 43.4% of the between-group differences in broad cognitive function. These results indicate that PPC dysfunction is central to WM storage deficits in PSZ and may play a key role in the broad cognitive deficits associated with schizophrenia.
SIGNIFICANCE STATEMENT People with schizophrenia exhibit cognitive deficits across a wide range of tasks. Explaining these impairments in terms of a small number of core deficits with clearly defined neural correlates would advance the understanding of the disorder and promote treatment development. We show that a substantial portion of broad cognitive deficits in schizophrenia can be explained by a failure to flexibly modulate posterior parietal cortex activity as a function of the amount of information currently stored in working memory. Working memory deficits have long been considered central to schizophrenia-related cognitive deficits, but the focus has been on paradigms involving some form of top-down control rather than pure storage of information, which may have unduly narrowed the focus on prefrontal dysfunction.
Auditory Predictive Coding across Awareness States under Anesthesia: An Intracranial Electrophysiology Study
The systems-level mechanisms underlying loss of consciousness (LOC) under anesthesia remain unclear. General anesthetics suppress sensory responses within higher-order cortex and feedback connections, both critical elements of predictive coding hypotheses of conscious perception. Responses to auditory novelty may offer promise as biomarkers for consciousness. This study examined anesthesia-induced changes in auditory novelty responses over short (local deviant [LD]) and long (global deviant [GD]) time scales, envisioned to engage preattentive and conscious levels of processing, respectively. Electrocorticographic recordings were obtained in human neurosurgical patients (3 male, 3 female) from four hierarchical processing levels: core auditory cortex, non-core auditory cortex, auditory-related, and PFC. Stimuli were vowel patterns incorporating deviants within and across stimuli (LD and GD). Subjects were presented with stimuli while awake, and during sedation (responsive) and following LOC (unresponsive) under propofol anesthesia. LD and GD effects were assayed as the averaged evoked potential and high gamma (70–150 Hz) activity. In the awake state, LD and GD effects were present in all recorded regions, with averaged evoked potential effects more broadly distributed than high gamma activity. Under sedation, LD effects were preserved in all regions, except PFC. LOC was accompanied by loss of LD effects outside of auditory cortex. By contrast, GD effects were markedly suppressed under sedation in all regions and were absent following LOC. Thus, although the presence of GD effects is indicative of being awake, its absence is not indicative of LOC. Loss of LD effects in higher-order cortical areas may constitute an alternative biomarker of LOC.
SIGNIFICANCE STATEMENT Development of a biomarker that indexes changes in the brain upon loss of consciousness (LOC) under general anesthesia has broad implications for elucidating the neural basis of awareness and clinical relevance to mechanisms of sleep, coma, and disorders of consciousness. Using intracranial recordings from neurosurgery patients, we investigated changes in the activation of cortical networks involved in auditory novelty detection over short (local deviance) and long (global deviance) time scales associated with sedation and LOC under propofol anesthesia. Our results indicate that, whereas the presence of global deviance effects can index awareness, their loss cannot serve as a biomarker for LOC. The dramatic reduction of local deviance effects in areas beyond auditory cortex may constitute an alternative biomarker of LOC.
The Adhesion-GPCR BAI1 Promotes Excitatory Synaptogenesis by Coordinating Bidirectional Trans-synaptic Signaling
Excitatory synapses are specialized cell–cell contacts located on actin-rich dendritic spines that mediate information flow and storage in the brain. The postsynaptic adhesion-G protein-coupled receptor (A-GPCR) BAI1 is a critical regulator of excitatory synaptogenesis, which functions in part by recruiting the Par3-Tiam1 polarity complex to spines, inducing local Rac1 GTPase activation and actin cytoskeletal remodeling. However, a detailed mechanistic understanding of how BAI1 controls synapse and spine development remains elusive. Here, we confirm that BAI1 is required in vivo for hippocampal spine development, and we identify three distinct signaling mechanisms mediating BAI1's prosynaptogenic functions. Using in utero electroporation to sparsely knock down BAI1 expression in hippocampal pyramidal neurons, we show that BAI1 cell-autonomously promotes spinogenesis in the developing mouse brain. BAI1 appears to function as a receptor at synapses, as its extracellular N-terminal segment is required for both its prospinogenic and prosynaptogenic functions. Moreover, BAI1 activation with a Stachel-derived peptide, which mimics a tethered agonist motif found in A-GPCRs, drives synaptic Rac1 activation and subsequent spine and synapse development. We also reveal, for the first time, a trans-synaptic function for BAI1, demonstrating in a mixed-culture assay that BAI1 induces the clustering of presynaptic vesicular glutamate transporter 1 (vGluT1) in contacting axons, indicative of presynaptic differentiation. Finally, we show that BAI1 forms a receptor complex with the synaptogenic cell-adhesion molecule Neuroligin-1 (NRLN1) and mediates NRLN1-dependent spine growth and synapse development. Together, these findings establish BAI1 as an essential postsynaptic A-GPCR that regulates excitatory synaptogenesis by coordinating bidirectional trans-synaptic signaling in cooperation with NRLN1.
SIGNIFICANCE STATEMENT Adhesion-G protein-coupled receptors are cell-adhesion receptors with important roles in nervous system development, function, and neuropsychiatric disorders. The postsynaptic adhesion-G protein-coupled receptor BAI1 is a critical regulator of dendritic spine and excitatory synapse development. However, the mechanism by which BAI1 controls these functions remains unclear. Our study identifies three distinct signaling paradigms for BAI1, demonstrating that it mediates forward, reverse, and lateral signaling in spines. Activation of BAI1 by a Stachel-dependent mechanism induces local Rac1 activation and subsequent spinogenesis/synaptogenesis. BAI1 also signals trans-synaptically to promote presynaptic differentiation. Furthermore, BAI1 interacts with the postsynaptic cell-adhesion molecule Neuroligin-1 (NRLN1) and facilitates NRLN1-dependent spine growth and excitatory synaptogenesis. Thus, our findings establish BAI1 as a functional synaptogenic receptor that promotes presynaptic and postsynaptic development in cooperation with synaptic organizer NRLN1.
A Neuronal Ensemble in the Rostral Agranular Insula Tracks Cocaine-Induced Devaluation of Natural Reward and Predicts Cocaine Seeking
In substance use disorders, negative affect associated with drug withdrawal can elicit strong drug craving and promote relapse. One brain region implicated in those processes is the rostral agranular insular cortex (RAIC), although precisely how this region encodes negative affect associated with drug seeking is unknown. Here, a preclinical model was used where RAIC activity was examined in male Sprague Dawley rats during intraoral infusions of a sweet (saccharin) paired with impending but delayed access to cocaine self-administration, and for comparative purposes, during the sweet predicting saline self-administration or injection of lithium chloride (LiCl), or during intraoral infusions of a bitter taste (quinine). Consistent with previous work, cocaine-paired saccharin, LiCl-paired saccharin, and quinine all elicited aversive taste reactivity. However, the aversive taste reactivity elicited by the cocaine-paired tastant was qualitatively different from that evoked by the other two agents. Furthermore, differences in taste reactivity were reflected in RAIC cell firing, where distinct shifts in neural signaling were observed specifically after cocaine but not LiCl conditioning. Notably, low motivation for cocaine (indicated by low loading and slower latencies to lever press) was correlated with this shift in RAIC signaling, but aversive (gaping) responses were not. Collectively, these findings indicate that cocaine-paired tastants elicit unique aspects of aversive behaviors that differ from traditional conditioned taste aversion (LiCl) or quinine and that the RAIC plays a role in modulating drug-seeking behaviors driven by drug-induced dysphoria (craving), but not negative affect per se.
SIGNIFICANCE STATEMENT In substance use disorders, negative affect associated with drug cues can elicit craving and promote relapse; however, the underlying neurocircuitry of this phenomenon is unknown. Here, we investigated the role of the rostral agranular insula cortex (RAIC) in these processes using a preclinical model wherein intraoral delivery of a sweet is paired with delayed access to cocaine self-administration. The taste comes to elicit negative affect that predicts heightened drug seeking. Here, we found that a population of RAIC neurons became inhibited during presentation of the cocaine-paired tastant (when negative affect is high) and that this inhibitory neural profile predicted lower drug seeking. These findings suggest that the RAIC may function to oppose cue-induced cocaine craving and help reduce motivation for the drug.
A Functional riboSNitch in the 3' Untranslated Region of FKBP5 Alters MicroRNA-320a Binding Efficiency and Mediates Vulnerability to Chronic Post-Traumatic Pain
Previous studies have shown that common variants of the gene coding for FK506-binding protein 51 (FKBP5), a critical regulator of glucocorticoid sensitivity, affect vulnerability to stress-related disorders. In a previous report, FKBP5 rs1360780 was identified as a functional variant because of its effect on gene methylation. Here we report evidence for a novel functional FKBP5 allele, rs3800373. This study assessed the association between rs3800373 and post-traumatic chronic pain in 1607 women and men from two ethnically diverse human cohorts. The molecular mechanism through which rs3800373 affects adverse outcomes was established via in silico, in vivo, and in vitro analyses. The rs3800373 minor allele predicted worse adverse outcomes after trauma exposure, such that individuals with the minor (risk) allele developed more severe post-traumatic chronic musculoskeletal pain. Among these individuals, peritraumatic circulating FKBP5 expression levels increased as cortisol and glucocorticoid receptor (NR3C1) mRNA levels increased, consistent with increased glucocorticoid resistance. Bioinformatic, in vitro, and mutational analyses indicate that the rs3800373 minor allele reduces the binding of a stress- and pain-associated microRNA, miR-320a, to FKBP5 via altering the FKBP5 mRNA 3'UTR secondary structure (i.e., is a riboSNitch). This results in relatively greater FKBP5 translation, unchecked by miR-320a. Overall, these results identify an important gene–miRNA interaction influencing chronic pain risk in vulnerable individuals and suggest that exogenous methods to achieve targeted reduction in poststress FKBP5 mRNA expression may constitute useful therapeutic strategies.
SIGNIFICANCE STATEMENT FKBP5 is a critical regulator of the stress response. Previous studies have shown that dysregulation of the expression of this gene plays a role in the pathogenesis of chronic pain development as well as a number of comorbid neuropsychiatric disorders. In the current study, we identified a functional allele (rs3800373) in the 3'UTR of FKBP5 that influences vulnerability to chronic post-traumatic pain in two ethnic cohorts. Using multiple complementary experimental approaches, we show that the FKBP5 rs3800373 minor allele alters the secondary structure of FKBP5 mRNA, decreasing the binding of a stress- and pain-associated microRNA, miR-320a. This results in relatively greater FKBP5 translation, unchecked by miR-320a, increasing glucocorticoid resistance and increasing vulnerability to post-traumatic pain.
TRPM2 Exacerbates Central Nervous System Inflammation in Experimental Autoimmune Encephalomyelitis by Increasing Production of CXCL2 Chemokines
Multiple sclerosis (MS) is a chronic inflammatory disorder of the CNS characterized by demyelination and axonal injury. Current therapies that mainly target lymphocytes do not fully meet clinical need due to the risk of severe side effects and lack of efficacy against progressive MS. Evidence suggests that MS is associated with CNS inflammation, although the underlying molecular mechanism is poorly understood. Transient receptor potential melastatin 2 (TRPM2), a Ca2+-permeable nonselective cation channel, is expressed at high levels in the brain and by immune cells, including monocyte lineage cells. Here, we show that TRPM2 plays a pathological role in experimental autoimmune encephalomyelitis (EAE), an animal model of MS. Knockout (KO) or pharmacological inhibition of TRPM2 inhibited progression of EAE and TRPM2-KO mice showed lower activation of Iba1-immunopositive monocyte lineage cells and neutrophil infiltration of the CNS than WT mice. Moreover, CXCL2 production in TRPM2-KO mice was significantly reduced at day 14, although the severity of EAE was the same as that in WT mice at that time point. In addition, we used BM chimeric mice to show that TRPM2 expressed by CNS-infiltrating macrophages contributes to progression of EAE. Because CXCL2 induces migration of neutrophils, these results indicate that reduced expression of CXCL2 in the CNS suppresses neutrophil infiltration and slows progression of EAE in TRPM2-KO mice. Together, the results suggest that TRPM2 plays an important role in progression of EAE pathology and shed light on its putative role as a therapeutic target for MS.
SIGNIFICANCE STATEMENT Current therapies for multiple sclerosis (MS), which mainly target lymphocytes, carry the risk of severe side effects and lack efficacy against the progressive form of the disease. Here, we found that the transient receptor potential melastatin 2 (TRPM2) channel, which is abundantly expressed in CNS-infiltrating macrophages, plays a crucial role in development of experimental autoimmune encephalomyelitis (EAE), an animal model of MS. EAE progression was suppressed by Knockout (KO) or pharmacological inhibition of TRPM2; this was attributed to a reduction in CXCL2 chemokine production by CNS-infiltrating macrophages in TRPM2-KO mice, resulting in suppression of neutrophil infiltration into the CNS. These results reveal an important role of TRPM2 in the pathogenesis of EAE and shed light on its potential as a therapeutic target.
Interneuron Simplification and Loss of Structural Plasticity As Markers of Aging-Related Functional Decline
Changes in excitatory neuron and synapse structure have been recognized as a potential physical source of age-related cognitive decline. Despite the importance of inhibition to brain plasticity, little is known regarding aging-associated changes to inhibitory neurons. Here we test for age-related cellular and circuit changes to inhibitory neurons of mouse visual cortex. We find no substantial difference in inhibitory neuron number, inhibitory neuronal subtypes, or synapse numbers within the cerebral cortex of aged mice compared with younger adults. However, when comparing cortical interneuron morphological parameters, we find differences in complexity, suggesting that arbors are simplified in aged mice. In vivo two-photon microscopy has previously shown that in contrast to pyramidal neurons, inhibitory interneurons retain a capacity for dendritic remodeling in the adult. We find that this capacity diminishes with age and is accompanied by a shift in dynamics from balanced branch additions and retractions to progressive prevalence of retractions, culminating in a dendritic arbor that is both simpler and more stable. Recording of visually evoked potentials shows that aging-related interneuron dendritic arbor simplification and reduced dynamics go hand in hand with loss of induced stimulus-selective response potentiation (SRP), a paradigm for adult visual cortical plasticity. Chronic treatment with the antidepressant fluoxetine reversed deficits in interneuron structural dynamics and restored SRP in aged animals. Our results support a structural basis for age-related impairments in sensory perception, and suggest that declines in inhibitory neuron structural plasticity during aging contribute to reduced functional plasticity.
SIGNIFICANCE STATEMENT Structural alterations in neuronal morphology and synaptic connections have been proposed as a potential physical basis for age–related decline in cognitive function. Little is known regarding aging-associated changes to inhibitory neurons, despite the importance of inhibitory circuitry to adult cortical plasticity and the reorganization of cortical maps. Here we show that brain aging goes hand in hand with progressive structural simplification and reduced plasticity of inhibitory neurons, and a parallel decline in sensory map plasticity. Fluoxetine treatment can attenuate the concurrent age–related declines in interneuron structural and functional plasticity, suggesting it could provide an important therapeutic approach for mitigating sensory and cognitive deficits associated with aging.
Identification of cell-associated and secreted serine-type peptidases in multidrug-resistant emergent pathogens belonging to the Candida haemulonii complex
Abstract
The Candida haemulonii complex (Candida haemulonii, Candida haemulonii var. vulnera, and Candida duobushaemulonii) comprises emerging opportunistic human fungal pathogens with recognized multidrug-resistance profiles. Little is known about the virulence markers produced by this fungal complex. However, it is recognized that Candida spp. express a large array of peptidases, which play multiple roles in different aspects of fungal-host interactions. In the present study, we have identified proteolytic enzymes in clinical isolates of the C. haemulonii complex using zymographic assays. Peptidases able to hydrolyze gelatin, casein, albumin, hemoglobin, and immunoglobulin G were detected in cell-free supernatants and cellular extracts taken from the three species forming the C. haemulonii complex. Overall, peptidases were preferentially evidenced at physiological pH and temperatures of 37–42 °C, with molar masses between 35 and 85 kDa. Peptidase profiles of C. haemulonii and C. haemulonii var. vulnera isolates were quite similar, contrasting to the peptidases produced by C. duobushaemulonii. Almost all peptidases were inhibited by phenylmethanesulfonyl fluoride (PMSF), thus classifying them as serine-type peptidases. Additionally, proteolytic cleavage of soluble azoalbumin was blocked by PMSF (65–95% inhibition depending on the fungal isolate). These unprecedented results have demonstrated the capability of the C. haemulonii complex to produce serine-type peptidases with an ability to cleave a broad spectrum of proteins, including key host components.
Current Climate for Digital Game-Based Learning of Science in Further and Higher Education
Abstract
Digital game-based learning (DGBL) is being used increasingly as an alternative learning tool to teach science in further and higher education. A variety of digital game formats currently exists for science learning, alongside diverse methods for their implementation and evaluation. This paper aims to provide a broad summary of the field by discussing the current platforms for DGBL and examples of games played on them. These include gamified simulations and traditional digital games delivered through personal computer (PC) and online software; mobile games delivered through downloaded applications for devices such as tablets and mobile phones; and educational modifications of commercial games, known amongst gamers as 'mods'. To conclude the summary, the paper discusses the current challenges and barriers associated with DGBL in further and higher science education, and potential strategies researchers may consider to overcome them.Molecular imaging reporting and data systems (MI-RADS): a generalizable framework for targeted radiotracers with theranostic implications
Abstract
Both prostate-specific membrane antigen (PSMA)- and somatostatin receptor (SSTR)-targeted positron emission tomography (PET)-based imaging agents for prostate carcinoma and neuroendocrine tumors, respectively, are seeing rapidly expanding use. In addition to diagnostic applications, both classes of radiotracers can be used to triage patients for theranostic endoradiotherapy. While interpreting PSMA- or SSTR-targeted PET/computed tomography (CT) scans, the reader has to be aware of certain pitfalls. Adding to the complexity of the interpretation of those imaging agents, both normal biodistribution, and also false-positive and -negative findings differ between PSMA- and SSTR-targeted PET radiotracers. Herein summarized under the umbrella term molecular imaging reporting and data systems (MI-RADS), two novel RADS classifications for PSMA- and SSTR-targeted PET imaging are described (PSMA- and SSTR-RADS). Notably, PSMA- and SSTR-RADS are structured in a reciprocal fashion, i.e., if the reader is familiar with one system, the other system can readily be applied, as well. In the present review, we will discuss the most common pitfalls on PSMA- and SSTR-targeted PET/CT, briefly introduce PSMA- and SSTR-RADS, and define a potential future role of the umbrella framework MI-RADS compared to other classification systems.
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Publication date: Available online 25 July 2018 Source: Journal of Photochemistry and Photobiology B: Biology Author(s): Marco Ballestr...
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Editorial AJR Reviewers: Heartfelt Thanks From the Editors and Staff Thomas H. Berquist 1 Share + Affiliation: Citation: American Journal...
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Publication date: Available online 28 September 2017 Source: Actas Dermo-Sifiliográficas Author(s): F.J. Navarro-Triviño
