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Δευτέρα 30 Οκτωβρίου 2017

Dermatological and environmental toxicological impact of the sunscreen ingredient oxybenzone/benzophenone-3

Summary

Oxybenzone (Benzophenone-3) is an emerging human and environmental contaminant used in sunscreens and personal care products to help minimize the damaging effects of ultraviolet radiation. The Center for Disease Control fourth national report on human exposure to environmental chemicals demonstrated that approximately 97% of the people tested have oxybenzone present in their urine, and independent scientists have reported various concentrations in waterways and fish worldwide. Oxybenzone can also react with chlorine, producing hazardous by-products that can concentrate in swimming pools and wastewater treatment plants. Moreover, adverse reactions could very well be increased by the closed loop of ingesting fish contaminated with oxybenzone and/or washing the ingredient off our bodies and having it return in drinking water as treatment plants do not effectively remove the chemical as part of their processing protocols. In humans, oxybenzone has been reported to produce contact and photocontact allergy reactions, implemented as a possible endocrine disruptor and has been linked to Hirschsprung's disease. Environmentally, oxybenzone has been shown to produce a variety of toxic reactions in coral and fish ranging from reef bleaching to mortality. Lastly, with the rise in skin cancer rates and the availability of more effective sunscreen actives such as micronized zinc oxide and titanium dioxide, serious doubts about the relative prevention benefit of personal care products containing oxybenzone must be raised and compared with the potential negative health and environmental effects caused by the accumulation of this and other chemicals in the ecosystem.



The pathogenesis of cutaneous squamous cell carcinoma in organ transplant recipients

Summary

The pathogenesis of keratinocyte carcinoma following organ transplantation is multifactorial, and recent evidence suggests a complex and often synergistic interplay between the carcinogenic effects of ultraviolet radiation, compromised immune surveillance, direct pro- and anticarcinogenic effects of drugs, oncogenic viruses (in particular, beta-genus human papillomaviruses) and host genetic susceptibility factors. We present an overview of those factors for which there is currently the most convincing evidence and highlight important gaps in our knowledge. In particular, a clear understanding of the interdependence and relative contributions of these co-factors is currently lacking, yet has important implications for rational development of clinically relevant biomarkers and targeted strategies for treatment and prevention of post-transplant keratinocyte cancers.



Research gaps in the management and prevention of cutaneous squamous cell carcinoma in organ transplant recipients

Summary

Although tremendous progress has been made in recent years in skin cancer care for organ transplant recipients, significant gaps remain in data-driven clinical guidelines, particularly for the treatment and prevention of cutaneous squamous cell carcinoma (cSCC), the most common malignancy among this population. In this review, we aim to summarize current knowledge around the management of cSCC and highlight the most significant gaps in knowledge that continue to pose challenges in the delivery of skin cancer care for organ transplant recipients. We suggest future directions for research that will bridge existing gaps and establish evidence-driven guidelines for primary prevention, screening and treatment of cSCC in this high-risk patient population.



TRPA1 channel participates in tacrolimus-induced pruritus in a chronic contact hypersensitivity murine model

Tacrolimus ointment (FK506), a calcineurin inhibitor, is a widely used topical medication in atopic dermatitis (AD) [1]. Although it is effective, pruritus and stinging sensation are common, particularly in AD patients [1]. Mediators of mast cells such as histamine have been suggested to be involved in the pathogenesis of tacrolimus-related pruritus by binding to the corresponding receptors on sensory nerve fibers [2]. Histamine acts on histamine receptors (HR) and activates the downstream transduction channel transient receptor potential V1 (TRPV1), which induces histamine-dependent pruritus [3].

Objective assessment of colonoscope manipulation skills in colonoscopy training

Abstract

Objective

Manipulation of the colonoscope is a technical challenge for novice clinicians which is best learned in a simulated environment. It involves the coordination of scope tip steering with scope insertion, using a rotated image as reference. The purpose of this work is to develop and validate a system which objectively assesses colonoscopy technical skills proficiency in an arbitrary training environment, allowing novices to assess their technical proficiency prior to real patient encounters.

Methods

We implemented a motion tracking setup to objectively analyze and assess the way operators perform colonoscopies, including an analysis of wrist and elbow joint motions. Subsequently, we conducted a validation study to verify whether our motion analysis could discriminate novice colonoscopists from experts. Participants navigated a wooden bench-top model using a standard colonoscope while their motions were tracked.

Results

The developed motion tracking setup allowed colonoscopists of varying levels of proficiency to have their colonoscope manipulation assessed, and was able to be operated by a trained non-technical operator. Novice operators had significantly greater median times (101.5 vs. 31.5 s) and number of hand movements (62.0 vs. 21.5) than experts. Experts, however, spent a significantly greater proportion of time in extreme ranges of wrist and elbow joint motion than novices.

Conclusion

We have developed and implemented a hand and joint motion analysis system that is able to discriminate novices from experts based on objective measures of motion. These metrics could, thus, serve as proxies for technical proficiency during training.



Releasing the “GENI”: integrating authentic microbial genomics research into the classroom through GENI-ACT

Abstract
The integration of genomics research into the undergraduate biology curriculum provides students with the opportunity to become familiar with bioinformatics tools and answer original research questions. Our purpose with this research project was to upscale the research experience through integration with classroom experience giving students access to authentic research projects. Students annotated 60 predicted ABC genes of Methanothermobacter thermautotrophicus and Methanobacterium sp. SWAN-1, and they were required to present a research poster to demonstrate their understanding of the project. During this research project a number of tests, assessments and surveys were conducted to assess familiarity with technical and conceptual understanding of genome annotation, satisfaction with annotation instruction, gain in bioinformatics research skills, scientific communications skills and increased student interest in research. We found that students gained significant skills in bioinformatics, specifically genome annotation skills and also gained confidence in their abilities to carry out scientific research. As a result of this authentic undergraduate research experience under-represented students were motivated to pursue future careers in STEM fields.

Plasmids can transfer to Clostridium difficile CD37 and 630Δ erm both by a DNase resistant conjugation-like mechanism and a DNase sensitive mechanism

Abstract
Broad host range conjugative plasmids that replicate in Escherichia coli have been widely used to mobilise smaller replicons, bearing their cognate origin of transfer (oriT) into a variety of organisms that are less tractable genetically, such as Clostridium (Clostridioides) difficile. In this work we demonstrated that the oriT region of pMTL9301 (derived from RK2) is not required for transfer between E. coli and C. difficile strains 630Δerm and CD37 and that this oriT-independent transfer is abolished in the presence of DNase when CD37 is the recipient. Transfer to the 630Δerm strain is DNase resistant even without an obvious oriT, when E. coli CA434 is used as a donor and is sensitive to DNase when E. coli HB101 is the donor.

Keeping education fresh—not just in microbiology

Abstract
Innovative practice from around the globe, addressing a range of recent educational themes and trends, was published in the FEMS Microbiology Letters virtual Thematic Issue 'Keeping Education Fresh' in October 2017. Its thought-provoking content is reviewed here to more directly facilitate reflections and discussions in the professional community. The focus is on best practice approaches when enhancing student engagement, how to adjust those to the diversity of learners, learning situations and infrastructures, and to a broad range of subjects. The need for authentic learning and to move away from didactic teaching is emphasized. The 'students as researchers' theme is featured e.g. in context of service learning. Creative approaches are presented such as using performing arts, popular culture and gamification. The development of interdisciplinary and intercultural competences, and the exploration of socioscientific themes and philosophical issues are considered. Revisions of curricula and programmes, reflective of educational advancements and sector drivers, are discussed from undergraduate to postgraduate and professional specialist level also in light of problem-based learning, interactive distance and on-campus learning, and even the legacy of Massive Open Online Courses. Such changes always require resources and skills, and carry risks. Yet, innovation is a risk worth taking to keep education fresh.

Microbial organic acid production as carbon dioxide sink

Abstract
Mixed-substrate conversions are an under-regarded option to fix carbon dioxide in significant amounts. In such a conversion, carbon dioxide together with one other carbon source such as glucose is converted to a single carbon product. With mixed-substrate conversions, it is possible to incorporate carbon dioxide into products with higher oxidation states than the co-substrate. Using abundant co-substrates such as glucose, glycerol or methanol, it is possible to produce organic acids anaerobically, using CO2 both as an electron acceptor and as an additional carbon source. Here, we outline the thermodynamic feasibility to produce industrially important organic acids with this approach to provide guidance for future metabolic engineering endeavours.

Degradation of the recalcitrant oil spill components anthracene and pyrene by a microbially driven Fenton reaction

Abstract
Oil spill components include a range of toxic saturated, aromatic and polar hydrocarbons, including pyrene and anthracene. Such contaminants harm natural ecosystems, adversely affect human health and negatively impact tourism and the fishing industries. Current physical, chemical and biological remediation technologies are often unable to completely remove recalcitrant oil spill components, which accumulate at levels greater than regulatory limits set by the Environmental Protection Agency. In the present study, a microbially driven Fenton reaction, previously shown to produce hydroxyl (HO•) radicals that degrade chlorinated solvents and associated solvent stabilizers, was also found to degrade source zone concentrations of the oil spill components, pyrene (10 μM) and anthracene (1 μM), at initial rates of 0.82 and 0.20 μM h−1, respectively. The pyrene- and anthracene-degrading Fenton reaction was driven by the metal-reducing facultative anaerobe Shewanella oneidensis exposed to alternating aerobic and anaerobic conditions in the presence of Fe(III). Similar to the chlorinated solvent degradation system, the pyrene and anthracene degradation systems required neither the continual supply of exogenous H2O2 nor UV-induced Fe(III) reduction to regenerate Fe(II). The microbially driven Fenton reaction provides the foundation for the development of alternate ex situ and in situ oil and gas spill remediation technologies.

Bioactive and biocontrol potential of endophytic fungi associated with Brugmansia aurea Lagerh

Abstract
This study describes 32 fungal endophytes isolated from different tissues of Brugmansia aurea Lagerh. Each fungal strain was authenticated based on internal transcribed spacer rDNA sequence. Phylogenetic analysis showed that these fungi are distributed in three classes, seven orders and 12 genera. The dichloromethane extracts of endophytic strains were screened for anticancer and antimicrobial activity. Anticancer activity of extracts against human cancer cell lines revealed that 50% strains are active with IC50 < 10 μg/mL. While analysing antimicrobial potential against both Gram-positive and Gram-negative bacteria, 56.25% endophytic strains displayed activity at least against one of the tested human pathogenic bacteria with minimum inhibitory concentration of 12.5–100 μg/mL. In vitro antagonistic activity of endophytes was analysed against Sclerotinia sp., Aspergillus fumigatus, Fusarium solani, A. flavus and F. oxysporum pathogen. The broad-spectrum anti-phytopathogenic activity was shown by R2BA. The presence of ketoacyl synthase domain of polyketide synthase gene and high degree of bioactivity shown by endophytic fungi suggested that they have potential to produce therapeutic compounds and to serve as biocontrol agent.

The Rural Plastic Surgery Residency Rotation: Rising to Meet a National Crisis

No abstract available

Plastic Surgery 2017: The Abstract Supplement

imageNo abstract available

Disseminierte rotbräunliche Papeln bei einem jungen Mann



Extracellular small heat shock proteins: exosomal biogenesis and function

Abstract

Small heat shock proteins (sHsps) belong to the family of heat shock proteins (Hsps): some are induced in response to multiple stressful events to protect the cells while others are constitutively expressed. Until now, it was believed that Hsps, including sHsps, are present inside the cells and perform intracellular functions. Interestingly, several groups recently reported the extracellular presence of Hsps, and sHsps have also been detected in sera/cerebrospinal fluids in various pathological conditions. Secretion into the extracellular milieu during many pathological conditions suggests additional or novel functions of sHsps in addition to their intracellular properties. Extracellular sHsps are implicated in cell-cell communication, activation of immune cells, and promoting anti-inflammatory and anti-platelet responses. Interestingly, exogenous administration of sHsps showed therapeutic effects in multiple disease models implying that extracellular sHsps are beneficial in pathological conditions. sHsps do not possess signal sequence and, hence, are not exported through the classical Endoplasmic reticulum-Golgi complex (ER-Golgi) secretory pathway. Further, export of sHsps is not inhibited by ER-Golgi secretory pathway inhibitors implying the involvement of a nonclassical secretory pathway in sHsp export. In lieu, lysoendosomal and exosomal pathways have been proposed for the export of sHsps. Heat shock protein 27 (Hsp27), αB-crystallin (αBC), and Hsp20 are shown to be exported by exosomes. Exosomes packaged with sHsps have beneficial effects in in vivo disease models. However, secretion mechanisms and therapeutic use of sHsps have not been elucidated in detail. Therefore, this review aimed at highlighting the current understanding of sHsps (Hsp27, αBC, and Hsp20) in the extracellular medium.



Views of Dermatopathologists about Clonality Assays in the Diagnosis of Cutaneous T cell and B cell Lymphoproliferative Disorders

Background

Appropriate use criteria have been developed for many tests using expert judgment, evidence-based practice, and clinical experience. In this context, the opinions of practitioners about clonality assays in various clinical scenarios where cutaneous lymphoma is suspected are reported.

Methods

An Appropriate Use Criteria Task Force sponsored by the American Society of Dermatopathology (ASDP) synthesized clinical scenarios for cutaneous lymphoproliferative disorders (LPD). We conducted, summarized, and presented a relevant literature search to an audience of 144 dermatopathologists with a variety of practice experiences at the 53rd Annual Meeting of the ASDP in Chicago, IL.

Results

27 clinical scenarios for lymphoproliferative disorders (13 T cell and 14 B cell) were defined. 40 relevant studies for T-cell receptor gene clonality assays and 20 relevant studies for IgH/IgK clonality assays were identified. Audience response data from participating dermatopathologists reflected a wide variety of approaches to the application of clonality assays in the evaluation of LPDs, based on practice setting, personal experience and test availability.

Conclusions

Our clinical scenario analysis and literature review revealed well supported clinical scenarios and identified opportunities for additional research to further define the utility of clonality assays in some clinical scenarios.



Soforttypreaktionen auf Protonenpumpeninhibitoren am Beispiel von Pantoprazol und Omeprazol

Zusammenfassung

Protonenpumpeninhibitoren (PPIs) gehören zu den am häufigsten eingenommenen Medikamenten weltweit. Allergien auf diese Substanzgruppe sind selten, können aber zu schweren Soforttypreaktionen führen. Insbesondere treten auch Kreuzreaktionen zwischen den verschiedenen PPIs auf. In dieser Fallserie werden 4 Patienten mit Soforttypreaktionen auf die Protonenpumpenhemmer Pantoprazol und/oder Omeprazol beschrieben.



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