Improvements in Modelling Bystander and Resident Exposure to Pesticide Spray Drift: Investigations into New Approaches for Characterizing the ‘Collection Efficiency’ of the Human Body

Abstract

The BREAM (Bystander and Resident Exposure Assessment Model) (Kennedy et al. in BREAM: A probabilistic bystander and resident exposure assessment model of spray drift from an agricultural boom sprayer. Comput Electron Agric 2012;88:63–71) for bystander and resident exposure to spray drift from boom sprayers has recently been incorporated into the European Food Safety Authority (EFSA) guidance for determining non-dietary exposures of humans to plant protection products. The component of BREAM, which relates airborne spray concentrations to bystander and resident dermal exposure, has been reviewed to identify whether it is possible to improve this and its description of variability captured in the model. Two approaches have been explored: a more rigorous statistical analysis of the empirical data and a semi-mechanistic model based on established studies combined with new data obtained in a wind tunnel. A statistical comparison between field data and model outputs was used to determine which approach gave the better prediction of exposures. The semi-mechanistic approach gave the better prediction of experimental data and resulted in a reduction in the proposed regulatory values for the 75th and 95th percentiles of the exposure distribution.

Dermalive Facial Filler Granulomas Masquerading as Neurofibromas

A 56-year-old woman presented with periocular nodules that were clinically suspected to be neurofibromas. Histopathologic examination of excised nodules revealed a pronounced granulomatous reaction to a foreign material that was composed of glossy polygonal palely eosinophilic fragments. These fragments were outlined in red with Masson trichrome, stained gray with the elastic stain, and were uniformly red with Gomori methenamine silver staining. The histopathologic appearance was consistent with a granulomatous reaction to Dermalive facial filler. Postoperatively the patient admitted that she had filler injections many years earlier in another country, and that nodules appeared 1 year after injection. Treatment with steroids, intralesional immunosuppressive agents and surgery had been previously attempted to eradicate the nodules. The literature pertaining to granulomatous reactions to Dermalive and related hybrid facial fillers is reviewed and treatment options are discussed. This report is the first to illustrate the unique histopathologic staining characteristics of Dermalive, which may be useful to ophthalmic pathologists in identifying this uncommon foreign material. Accepted for publication January 31, 2018. Heed Fellowship was awarded to N.W. The authors have no conflicts of interest to disclose. Address correspondence and reprint requests to Frederick A. Jakobiec, M.D., D.Sc., David G. Cogan Laboratory of Ophthalmic Pathology, Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, 243 Charles Street, Suite 328, Boston, MA 02114. E-mail: Fred_Jakobiec@meei.harvard.edu. © 2018 by The American Society of Ophthalmic Plastic and Reconstructive Surgery, Inc., All rights reserved.

Frontalis Muscle Contraction and the Role of Visual Deprivation and Eyelid Proprioception

Purpose: To determine if frontalis muscle contraction can be induced by manipulating visual and eyelid proprioceptive inputs through simulating visual deprivation and ptosis. Methods: Volunteers without prior eyelid or forehead pathologic study were recruited for this nonrandomized, prospective study. Baseline and study phase brow positions were documented. The first phase was to simulate visual deprivation and the second to simulate ptosis. The dominant eye was used for each phase. As a proxy to simulate visual field deprivation, a black contact lens was placed on the eye, which reduced vision to light perception. As a proxy to simulate ptosis, an external eyelid weight was placed on the upper eyelid. Brow position ratios were calculated at various points along the brow and statistical analysis was performed. Results: Fifteen subjects participated. The average brow position ratio was 1.00 ± 0.08 for the visual deprivation group, which was not different from baseline (p = 0.86). The average brow position ratio for the external eyelid weight group was 1.13 ± 0.07, which was statistically significant compared with baseline and the visual deprivation group (p

Primary Eyelid Amyloidosis Presenting as a Calcified Plaque: A Rare Presentation

No abstract available

Quantitative Assessment of Dry Eye Parameters After Muller’s Muscle-Conjunctival Resection

Purpose: Muller's muscle-conjunctival resection (MMCR) is a highly effective technique to correct upper eyelid ptosis. However, several authorities have raised concerns about the possibility of postoperative ocular surface dryness. This study was performed to assess the impact of MMCR on clinically meaningful parameters of the ocular surface. Methods: In adult patients, tear break-up time, lipid layer thickness, and osmolarity were measured via direct observation, interferometry, and impedance measurements before surgery and 3 months after surgery in patients who underwent MMCR. Statistical analysis was performed via a dedicated software package. Results: Fifteen eyes of 14 patients were included in the study. Mean pre- and postoperative tear break-up times were 12.71 ± 2.20 and 12.43 ± 2.41 seconds, respectively (p = 0.1648). Preoperatively, the mean lipid layer thickness measurement was 91.00 ± 7.02 nm, whereas the mean postoperative value was 88.86 ± 21.36 nm (p = 0.6613). The mean preoperative tear osmolarity measured 291.4 ± 8.86 mOsm/l, and the mean postoperative measurement was 289.86 ± 9.74 mOsm/l (p = 0.2652). Conclusions: MMCR does not appear to change clinically meaningful ocular surface disease parameters, and postoperative dryness did not result from this procedure. In appropriately selected patients, MMCR can be safely performed without increased concerns regarding postoperative dry eye disease. Accepted for publication February 4, 2018. The research adhered to the tenets of the Declaration of Helsinki as amended in 2008. The abstract of this manuscript has been presented at the American Society of Ophthalmic Plastic and Reconstructive Surgery (ASOPRS) Annual Meeting, American Academy of Ophthalmology, New Orleans, Louisiana, November 10, 2017 Fall Scientific Symposium. The authors have no financial or conflicts of interest to disclose. Address correspondence and reprint requests to: Sana Ali Bautista, M.D., Department of Ophthalmology, Albany Medical College, 43 New Scotland Avenue, Albany, NY 12208. E-mail: alis4@amc.edu © 2018 by The American Society of Ophthalmic Plastic and Reconstructive Surgery, Inc., All rights reserved.

A Simple Quantitative Measure of Orbital Compliance

Purpose: This study evaluates the reliability of a frequently used subjective measurement of orbital compliance (0–3 scale) and describes a simple, quantitative measure with excellent intra- and interrater reliability. Methods: Two examiners performed both measurements on 100 orbits (50 consecutive patients) from the office of 1 oculoplastics surgeon. Each measurement was obtained at 2 different time points, 10 minutes apart. For the subjective measurement, the patient was asked to close their eyes, and the globe was displaced posteriorly with digital pressure until moderate resistance was felt. This was graded on a 0 to 3 scale. For the quantitative measurement (millimeter scale), the difference in axial displacement was measured using a Hertel exophthalmometer. Results: The subjective measurement (scale, 0–3) showed excellent test–retest reliability (average, 0.901) for both examiners at both time points and good interobserver reliability (average, 0.677). The quantitative measurement (millimeter scale) showed excellent test–retest reliability (average, 0.848) and very good interobserver reliability (average, 0.756). Conclusion: This study shows that while both methods have both excellent test–retest reliability, the interobserver reliability is slightly higher with the quantitative measurement. This suggests that the described measurement of orbital compliance is both a reasonable alternative and possibly more accurate measurement without the steep learning curve. Accepted for publication January 31, 2018. A consent was obtained and is on file for the figure used in the paper. Supported by an unrestricted grant from Research to Prevent Blindness to Columbia University School of Medicine. The authors have no financial or conflicts of interest to disclose. This work has not been published or presented at any meeting previously. Address correspondence and reprint requests to: Michael Kazim, M.D., Harkness Eye Institute, Columbia University Medical Center, 635 West 165th Street, New York, NY 10032. E-mail: mk48@cumc.columbia.edu © 2018 by The American Society of Ophthalmic Plastic and Reconstructive Surgery, Inc., All rights reserved.

Orbital and Ocular Ischemic Syndrome With Blindness After Facial Filler Injection

The authors herein describe a case of orbital and ocular ischemic syndrome with blindness after cosmetic hyaluronic acid filler injection. Orbital function, but not visual function, returned after treatment with orbital hyaluronidase and corticosteroids. Accepted for publication February 4, 2018. The authors have no financial or conflicts of interest to disclose. Address correspondence and reprint requests to Sathyadeepak Ramesh, M.D., UCLA Stein Eye Institute, 300 Stein Plaza, Los Angeles, CA 90095. E-mail: Sathyadeepak.Ramesh@gmail.com © 2018 by The American Society of Ophthalmic Plastic and Reconstructive Surgery, Inc., All rights reserved.

Orbital Plates and Screws Causing Globe Fixation: A Rare and Delayed Complication of Craniomaxillofacial Surgery

A 24-year-old woman presented with a 1-year history of gradually increasing pain on eye movements, worse on the right. She had a significant background of undergoing intracranial correction of orbital hypertelorism with internal fixation of the lateral orbital rims at the age of 6 years. Imaging was consistent with bilateral metallic foreign bodies from both lateral orbital rims protruding into the globes. The patient underwent removal of bilateral plates and screws, with a significant improvement of symptoms and ocular motility postoperatively. This case demonstrates the need to consider orbital screw/plate migration in the setting of reduced ocular motility and painful eye movements. Accepted for publication January 25, 2018. Written consent was gained from the patient for publication and use of photographs The authors have no financial or conflicts of interest to disclose. Address correspondence and reprint requests to: Varun Chandra, M.B.B.S., Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne, VIC, Australia. E-mail: varun.chandra@hotmail.com © 2018 by The American Society of Ophthalmic Plastic and Reconstructive Surgery, Inc., All rights reserved.

Validation of reference genes for reverse transcription real-time quantitative PCR analysis in the deep-sea bacterium Shewanella psychrophila WP2

Abstract

Reference genes are critical to obtain reliable results of reverse transcription real-time quantitative PCR (RT-qPCR), which is widely used for relative quantification of gene expression. In this study, we evaluated the validity of seven candidate reference genes for normalization in RT-qPCR analysis in the deep-sea bacterium Shewanella psychrophila WP2 under different environmental conditions. Among the set of genes investigated, gyrA, 16S rRNA and rho were identified as the most suitable reference genes for WP2 at different temperatures, hydrostatic pressures and salinities, respectively. Notably, the rho gene is conserved in Shewanella genus and other deep-sea bacteria, thus, could be used as a versatile reference gene for RT-qPCR analysis of these microorganisms under extreme environmental conditions.

Fatty acid addition and thermotolerance of Kluyveromyces marxianus

Abstract

Membrane fatty acid composition has an important role in yeast stress resistance, particularly in temperature tolerance. Most studies investigating temperature and membrane fatty acids use the yeast Saccharomyces cerevisiae without considering other yeasts, such as Kluyveromyces marxianus, which has physiological differences and industrial advantages with respect to S. cerevisiae. One of the primary traits of K. marxianus is its thermotolerance. The effect of fatty acid addition (oleic acid, linoleic acid, linolenic acid and araquidic acid) on the thermotolerance of the K. marxianus strain SLP1 was evaluated. SLP1 yeast exhibited temperature tolerance of up to 50°C; at 55°C, viability was reduced significantly, probably due to an increase in the generation of reactive oxygen chemical species. Externally added fatty acids were incorporated in the yeast membrane, increasing their proportion to approximately 70%, thereby changing membrane fluidity. SLP1 cells supplemented with polyunsaturated fatty acids decreased cell thermotolerance and increased the degree of lipoperoxidation, while arachidic acid addition exhibited a tendency to increase yeast thermotolerance.

Variable response of nirK and nirS containing denitrifier communities to long-term pH manipulation and cultivation

Abstract

Denitrification is a key process responsible for the majority of soil nitrous oxide (N₂O) emissions but the influences of pH and cultivation on the soil denitrifier community remain poorly understood. We hypothesised that the abundance and community structure of the total bacterial community and bacterial denitrifiers would be pH sensitive and that nirK and nirS containing denitrifiers would differ in their responses to change in pH and cultivation. We investigated the effect of long-term pH-adjusted soils (ranging from pH 4.2 to 6.6) under different lengths of grass cultivation (one, two and three years of ley grass) on the general bacterial and denitrifier functional communities using 16S rRNA, nirK and nirS genes as markers. Denitrifier abundance increased with pH, and at pH below 4.7 there was a greater loss in nirS abundance per unit drop in pH than soils above this threshold pH. All community structures responded to changes in soil pH, while cultivation only influenced the community structure of nirK. These differences in denitrifier responses highlight the importance of considering both nirK and nirS gene markers for estimating denitrifier activity. Identifying such thresholds in response of the microbial community to changes in pH is essential to understanding impacts of management or environmental change.

Overexpression of the periplasmic nitrate reductase supports anaerobic growth by Ensifer meliloti

Abstract

The alfalfa endosymbiont Ensifer meliloti strain1021 is known to be an incomplete denitrifier due to its inability to grow anoxically using nitrate as respiratory substrate to produce ATP and grow under anoxic conditions. Although this bacterium contains and expresses the complete set of denitrification genes napEFDABC, nirK, norECBQD and nosRZDFYLX encoding the periplasmic nitrate reductase (Nap), Cu-containing nitrite reductase (NirK), c-type nitric oxide (cNor) and nitrous oxide reductase (Nos), respectively, the reasons of its inability to grow under anoxic conditions are still very poorly understood. In the present study, we have constructed an E. meliloti strain overexpressing napEFDABC genes (Nap⁺) and demonstrated that this strain is able to grow through anaerobic nitrate respiration. Furthermore, Nap⁺ showed increased NapC levels as well as Nap, Nir and cNor activities and higher capacity to produce NO and N₂O compared to wild-type cells. These results suggest that the inability of E. meliloti to grow under anaerobic conditions using nitrate as electron acceptor is attributable to a limitation in the expression of the periplasmic nitrate reductase.

Characterization of centriole duplication in human epidermis, Bowen’s disease, and squamous cell carcinoma

The centrosome is the microtubule-organizing center of animal cells. Each cell has one centrosome, comprising a pair of centrioles and the surrounding pericentriolar material (PCM) [1]. Centrosomes are involved in spindle pole assembly, cell polarity, cell migration, and maintenance of cellular stemness [2–4]. Numerical and structural centrosome abnormalities have been observed in many human carcinomas including pre-invasive carcinomas. It remains unclear whether centrosome abnormalities cause, or are a result of, tumorigenesis [5].

Enoxaparin pretreatment effect on local and systemic inflammation biomarkers in the animal burn model

Abstract

Low-molecular weight heparins (LMWH) are anticoagulants that have shown anti-inflammatory activity in several experimental models. Hot water burn inflammatory model accurately simulates human clinical situations allowing its use for nociception test and evaluation of anti-inflammatory drugs. The present study aims to evaluate the enoxaparin pretreatment on local and systemic inflammation biomarkers in the animal burn model. Inflammation was induced by submersing the rat left hind paw in water at 60^o C for 60 s. C-reactive protein (CRP) and thrombin–antithrombin complex (TAT) were estimated by immunosorbent assay, fibrinogen (Fg) by the gravimetric method and paw oedema by orthogonal digital photography. Highest values of paw oedema, CRP and TAT were observed at 4 h post-burn while Fg peak occurs at 12 h post-burn; enoxaparin pretreatment decreased oedema (− 32.1%), and concentration of TAT (− 66.7%), PCR (− 37.9%) and Fg (− 8%). This study shows that enoxaparin has local and systemic anti-inflammatory effects and should be considered as a potential adjuvant drug for the treatment of burns.

Differences between attached and suspended microalgal cells in ssPBR from the perspective of physiological properties

Publication date: Available online 15 March 2018
Source:Journal of Photochemistry and Photobiology B: Biology
Author(s): Zhuang Lin-Lan, Wang Jing-Han, Hu Hong-Ying
Attached microalgae cultivation for the algae-based products is considered as a promising approach to simplify biomass recovery processes and reduce the cost. However, as an incipient research field, biomass accumulation is the mainly index for attached microalgal growth evaluation. To break through such limitations, physiological properties of attached microalgae (e.g. the oxygen evolving activity and the three main organic composition of cells), which are important for microalgal growth evaluation but are still unclear in most studies, were studied using an attached microalgae culture system, i.e. suspended-solid phase photobioreactor (ssPBR) in this paper. As light, nutrients and other environmental conditions of attached microalgae were different from the suspended microalgae, physiological properties of attached microalgae also varied from the suspended ones. Besides the relatively lower biomass accumulation rate, attached microalgae also had a lower oxygen evolving activity (65% on average) comparing to suspended microalgae. The composition of microalgae changed towards accumulating more protein when suspended microalgae turned to attached status. The relative protein content of attached microalgae (50.1% ± 10.1%) was approximately 30% higher than the suspended algae (36.0% ± 16.1%) on average. The discovery of physiological properties of attached microalgae in this paper could help the production of high-protein microalgae-related products and explain some phenomenon during the production of microalgae-related products.

Neo-adjuvant radiotherapy (NART) in breast reconstruction – The future for autologous reconstruction in locally advanced disease?

Publication date: Available online 15 March 2018
Source:Journal of Plastic, Reconstructive & Aesthetic Surgery
Author(s): Pietro G. di Summa, Sherylin K. Tay, Rosemary Stevens, Julie C. Doughty, Russell J. Bramhall

Nanoanalytics: history, concepts, and specificities

Abstract

This article deals with analytical chemistry devoted to nano-objects. A short review presents nano-objects, their singularity in relation to their dimensions, genesis, and possible transformations. The term nano-object is then explained. Nano-object characterization activities are considered and a definition of nanoanalytics is proposed. Parameters and properties for describing nano-objects on an individual scale and on the scale of a population are also presented. They enable the specificities of analytical activities to be highlighted in terms of multi-criteria description strategies and observation scale. Special attention is given to analytical methods, their dimensioning and validation.

Breast cancer brain metastasis: molecular mechanisms and directions for treatment

Abstract

The development of brain metastasis (BM) of breast cancer is usually a late event with deleterious effect on the prognosis. Treatment options for intracerebral seeding of breast cancer are limited and so far, non-specific. Molecular detailing of subsequent events of penetration, seeding and outgrowth in brain is highly relevant for developing therapeutic strategies to treat, or prevent, BM.We scrutinize recent literature for molecules and pathways that are operative in the formation of breast cancer BM. We also summarize current data on therapeutic efforts to specifically address BM of breast cancer. Data on molecular pathways underlying the formation of BM of breast cancer are sketchy and to some extent inconsistent. The molecular make-up of BM differs from that of the primary tumors, and also from metastases at other sites. Current efforts to treat breast cancer BM are limited and drugs used have proven effects on the primary tumors but lack specificity for the intracerebral tumors.More basic research is necessary to better characterize BM of breast cancer. Apart from the identification of drug targets defined by the intracerebral tumors, also targets in the molecular pathways involved in passing the blood-brain-barrier (BBB) and intracerebral tumor cell (TC) growth should be revealed.

Effects of enhanced ultraviolet-B radiation, water deficit, and their combination on UV-absorbing compounds and osmotic adjustment substances in two different moss species

Abstract

A simulation experiment was conducted to explore the influence of enhanced ultraviolet-B (UV-B) radiation, water deficit, and their combination on UV-absorbing compounds and osmotic adjustment substances of mosses Bryum argenteum and Didymodon vinealis isolated from biological soil crusts (BSCs) growing in a revegetated area of the Tengger Desert, China. Four levels of UV-B radiation and two gradients of water regime were employed. Compared with their controls, amounts of total flavonoids, chlorophyll, carotenoids, soluble sugars, and soluble proteins significantly decreased (p < 0.05), but proline content significantly increased (p < 0.05), when exposed to either enhanced UV-B or water deficit. The negative effects of enhanced UV-B were alleviated when water deficit was applied. There were increases in UV-absorbing compounds and osmotic adjustment substances when exposed to a combination of enhanced UV-B and water deficit compared with single stresses, except for the proline content in D. vinealis. In addition, our results also indicated interspecific differences in response to enhanced UV-B, water deficit, and their combination. Compared with B. argenteum, D. vinealis was more resistant to enhanced UV-B and water deficit singly and in combination. These results suggest that the damage of enhanced UV-B on both species might be alleviated by water deficit. This alleviation is important for understanding the response of BSCs to UV-B radiation in future global climate change. This also provides novel insights into assessment damages of UV-B to BSC stability in arid and semiarid regions.

Climate variability and dengue hemorrhagic fever in Southeast Sulawesi Province, Indonesia

Abstract

To determine the association of climatic factors and dengue hemorrhagic fever and to develop the prediction approach of future dengue transmission. The study used totally monthly dengue hemorrhagic fever cases at Health Office Kendari, Southeast Sulawesi, Indonesia. Monthly meteorological data, consisting of temperature, rainfall, and humidity, was obtained from the Meteorology, Climatology and Geophysics Agency in Kendari district. All data analysis, including Spearman and Poisson distribution, was carried out in R Studio (version 3.3.2) utilizing the R statistical language version 2.15. The highest rate of dengue hemorrhagic fever cases was found in January, February, and March. Temperature averages at lag 2 (p = 0.53, p < 0.0001), lag 3 (p = 0.59, p < 0.0001), and lag 4 (p = 0.41, p < 0.01)) correlated with the incident rate of DHF. The average temperature at lag 2 was found to have a positive impact on the incidence of DHF by Poisson function. This study provides preliminary evidence of the influence of climatic factors on dengue transmission.

Site saturation mutagenesis of ribosomal protein L42 at 56th residue and application as a consecutive selection marker for cycloheximide resistance in yeast

Abstract

The 56^th residue of ribosomal protein L42 (Rpl42) determines the sensitivity of yeast cells to the antibiotic cycloheximide (CYH). In this study, we identified the relationship between the 56^th residue of Rpl42 and the function of the ribosome by site saturation mutagenesis. The resulting 20 RPL42 mutants harbouring one of 20 amino acids at the 56^th residue were classified into five groups: sensitive to CYH (RPL42aP); weak resistance (RPL42aA, RPL42aM, RPL42aC, RPL42aN, RPL42aD, RPL42aS, and RPL42aT), moderate resistance (RPL42aL, RPL42aI, RPL42aV, RPL42aG, and RPL42aH), and strong resistance (RPL42aQ, RPL42aE, RPL42aR, and RPL42aK) to CYH; and non-functional (RPL42aF, RPL42aY, and RPL42aW). Three RPL42a mutants from each group, RPL42aA, RPL42aL, and RPL42aQ, were used as CYH-resistant selection marker genes for the sequential transformation of CYH-sensitive yeast. A series of RPL42 mutants conferring different levels of resistance to CYH should be useful for the dose-dependent multiple selection of prototrophic industrial yeasts.

The nature of electron acceptor (MnIV/NO3) triggers differential expression of genes associated with stress and ammonium limitation responses in Shewanella algae C6G3

Abstract

Shewanella algae C6G3 can reduce dissimilatively nitrate into ammonium and manganese-oxide (MnIV) into MnII. It has the unusual ability to produce anaerobically nitrite from ammonium in the presence of MnIV. To gain insight into their metabolic capabilities, global mRNA expression patterns were investigated by RNA-seq and qRT-PCR in cells growing with lactate and ammonium as carbon and nitrogen sources and with either MnIV or nitrate as electron acceptors. Gene exhibiting higher expression levels in the presence of MnIV belonged to functional categories of carbohydrate, coenzyme, lipid metabolisms and inorganic ion transport. Comparative transcriptomic pattern between MnIV and NO₃ revealed that the strain presented an ammonium limitation status with MnIV, despite the presence of non-limiting concentration of ammonium under both culture conditions. In addition, in presence of MnIV, ntrB/nrtC regulators, ammonium channel, nitrogen regulatory protein P-II, glutamine synthetase and asparagine synthetase glutamine dependent genes were over-represented. Under nitrate condition, the expression of genes involved in the synthesis of several amino acids was increased. Finally, expression level of genes associated with the general stress response was also amplified and among them, katE, a putative catalase/peroxidase present on several Shewanella genomes, was highly expressed with a relative median value higher in MnIV condition.

Involvement of AmpG in mediating a dynamic relationship between serine beta-lactamase induction and biofilm forming ability of Escherichia coli

Abstract

AmpG permease is implicated both in beta-lactamase induction as well as peptidoglycan recycling in enterobacterial isolates. Here, physiological studies using molecular genetics show that deletion of AmpG permease dramatically increases beta-lactam susceptibility even in the presence of AmpC, TEM-1 and OXA beta-lactamases. Also, there is an appreciable decrease in the biofilm forming ability of strains lacking this protein. Expression of this permease in excess probably compromises the integrity of the bacterial cells, leading to cell lysis. Based on these results, we propose that AmpGpermease may be used as a potential antibiotic target and its suppression could efficiently inhibit both beta-lactamase induction and biofilm formation.

Functional characterization of the manganese transporter smf2 homologue gene, PsMnt, of Phanerochaete sordida YK-624 via homologous overexpression

Abstract

A homologue gene of the yeast natural resistance–associated macrophage protein (Nramp) family transporter smf2 was identified in the white-rot fungus Phanerochaete sordida YK-624. Relative expression levels of the homologue, designated PsMnt, were roughly equivalent in cultures containing 0 to 1,000 μM Mn(II), a concentration nontoxic to the fungus. In the PsMnt-overexpressing mutant, cellular Mn accumulation and manganese peroxidase (MnP) activity increased significantly in 4-day cultures containing 10 μM MnSO₄. Compared with the wild-type strain, MnP activity in the overexpressing mutants was higher at lower Mn concentrations (specifically 10–15 times higher). These results suggest that PsMnt is a high-affinity Mn transporter involved in cellular Mn accumulation under Mn-deficient conditions. This is the first report of an smf2 homologue in wood rot fungi.

Electrophoretic mobility of Legionella pneumophila serogroups 1 to 14

Abstract

Legionella pneumophila (Lp) is ubiquitous in the aquatic environment and can persist within drinking water distribution systems (DWDS) enabling these systems to serve as a potential source of human infections. Bacterial surface charge, deduced from electrophoretic mobility (EPM), is a well-recognized contributor to microorganism mobility, adherence, and interactions with their surrounding environment. In this study, the EPM of thirty-two Lp strains representing serogroup (sg) 1 to 14 were measured, in 9.15mM KH₂PO₄ at pH 8, to understand cell surface properties that may influence their occurrence within DWDS. EPM measurements indicated the charge of Lp varied widely between serogroups with five distinct clusters, from least to most negatively charged: (i) sg1 to 3, 5, and 12; (ii) sg6, 8, and 10; (iii) sg9 and 13; (iv) sg7, 11, and 14; and (v) sg4. The EPM of sg1 and 4 strains were pH dependent; however, values were constant between pH 6 to 9, a range typical of drinking water, suggesting that EPM differences between Lp serogroups could impact their survival within DWDS. Understanding the ecological importance of Lp surface properties (e.g. in mobility, colonization, resistance to disinfectants, etc.) within DWDS, would aid in mitigation of health risks associated with this water-based pathogen.

Taking it in the Chin: Vitamin K1 for the Prevention of Acneiform Rash

Optimization and characterization of biosurfactant production from kitchen waste oil using Pseudomonas aeruginosa

Abstract

Kitchen waste oil (KWO) from catering industries or households was used as a low-cost carbon source for producing biosurfactants by self-isolated Pseudomonas aeruginosa. Fermentation performance with KWO was superior to those with four other carbon sources, with higher optical density (OD₆₀₀) of 2.33 and lower interfacial tension of 0.57 mN/m. Culture conditions for biosurfactant production were optimized, with optimal pH of 8.0 and nitrogen source concentration of 2.0 g/L, respectively. The results of infrared spectroscopy and liquid chromatography-mass spectrometry (LC-MS) showed that the biosurfactant was a mixture of six rhamnolipid congeners, among which Rha-Rha-C₁₀-C₁₀ and Rha-C₁₀-C₁₀ were the main components, with mass fraction of approximately 34.20 and 50.86%, respectively. The critical micelle concentration (CMC) obtained was 55.87 mg/L. In addition, the rhamnolipids exhibited excellent tolerance to temperature (20–100 °C), pH (6.0–12.0), and salinity (2–20%; w/v) in a wide range, thereby showing good stability to extreme environmental conditions. The rhamnolipids positively affected oil removal from oil sludge and KWO-contaminated cotton cloth, with removal rate of 34.13 and of 30.92%, respectively. Our results demonstrated that biosurfactant production from KWO was promising, with advantages of good performance, low cost and environmental safety.

Correction to: The influencing factors of CO 2 emission intensity of Chinese agriculture from 1997 to 2014

Abstract

The correct name of the 2nd Author is Yusen Luo. The original article has been corrected.

hsa-let-7b-5p facilitates Mycobacterium tuberculosis survival in THP-1 human macrophages by Fas downregulation

Abstract

Tuberculosis continues to be one of the deadliest infectious diseases worldwide. MicroRNAs (miRNAs) are small non-coding entities that play critical role as post-transcriptional regulators and are transcriptionally deregulated upon mycobacterial infection. In this study, we found significant upregulation of hsa-let-7b-5p in Mycobacterium tuberculosis (MTB) infected THP-1 human macrophages. Concomitantly, we detected the reduced level of Fas protein, one of the targets of hsa-let-7b-5p, in MTB-infected THP-1 macrophages. Using luciferase assay, a direct interaction between hsa-let-7b-5p and the Fas 3΄-untranslated region (3΄-UTR) was established. Inhibition of hsa-let-7b-5p augmented the apoptosis of THP-1 cells enabling enhanced clearance of MTB. Our findings suggest that hsa-let-7b-5p helps intracellular survival of MTB in THP-1 cells by downregulating Fas protein level. This highlights hsa-let-7b-5p as a potential therapeutic target for tuberculosis treatment.

Isolation of marine xylene-utilizing bacteria and characterization of Halioxenophilus aromaticivorans gen. nov., sp. nov. and its xylene degradation gene cluster

Abstract

Seven xylene-utilizing bacterial strains were isolated from seawater collected off the coast of Japan. Analysis of 16S rRNA gene sequences indicated that six isolates were most closely related to the marine bacterial genera Alteromonas, Marinobacter or Aestuariibacter. The sequence of the remaining strain, KU68F^T, showed low similarity to the 16S rRNA gene sequences of known bacteria with validly published names, the most similar species being Maricurvus nonylphenolicus strain KU41E^T (92.6% identity). On the basis of physiological, chemotaxonomic and phylogenetic data, strain KU68F^T is suggested to represent a novel species of a new genus in the family Cellvibrionaceae of the order Cellvibrionales within the Gammaproteobacteria, for which the name Halioxenophilus aromaticivorans gen. nov., sp. nov. is proposed. The type strain of Halioxenophilus aromaticivorans is KU68F^T (=JCM 19134^T = KCTC 32387^T). PCR and sequence analysis revealed that strain KU68F^T possesses an entire set of genes encoding the enzymes for the upper xylene methyl-monooxygenase pathway, xylCMABN, resembling the gene set of the terrestrial Pseudomonas putida strain mt-2.