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Background: The important contribution of glia to mechanisms of injury and repair of the nervous system is increasingly recognized. In stark contrast to the central nervous system (CNS), the peripheral nervous system (PNS) has a remarkable capacity for regeneration after injury. Schwann cells are recognized as key contributors to PNS regeneration, but the molecular underpinnings of the Schwann cell response to injury and how they interact with the inflammatory response remain incompletely understood., Methods: We completed bulk RNA-sequencing of Schwann cells purified acutely using immunopanning from the naïve and injured rodent sciatic nerve at 3, 5, and 7 days post-injury. We used qRT-PCR and in situ hybridization to assess cell purity and probe dataset integrity. Finally, we used bioinformatic analysis to probe Schwann cell-specific injury-induced modulation of cellular pathways., Results: Our data confirm Schwann cell purity and validate RNAseq dataset integrity. Bioinformatic analysis identifies discrete modules of genes that follow distinct patterns of regulation in the 1st days after injury and their corresponding molecular pathways. These findings enable improved differentiation of myeloid and glial components of neuroinflammation after peripheral nerve injury and highlight novel molecular aspects of the Schwann cell injury response such as acute downregulation of the AGE/RAGE pathway and of secreted molecules Sparcl1 and Sema5a., Conclusions: We provide a helpful resource for further deciphering the Schwann cell injury response and a depth of transcriptional data that can complement the findings of recent single cell sequencing approaches. As more data become available on the response of CNS glia to injury, we anticipate that this dataset will provide a valuable platform for understanding key differences in the PNS and CNS glial responses to injury and for designing approaches to ameliorate CNS regeneration., (© 2022. The Author(s).)

The composition of the vaginal microbiome, including both the presence of pathogens involved in sexually transmitted infections (STI) as well as commensal microbiota, has been shown to have important associations for a woman's reproductive and general health. Currently, healthcare providers cannot offer comprehensive vaginal microbiome screening, but are limited to the detection of individual pathogens, such as high-risk human papillomavirus (hrHPV), the predominant cause of cervical cancer. There is no single test on the market that combines HPV, STI, and microbiome screening. Here, we describe a novel inclusive vaginal health assay that combines self-sampling with sequencing-based HPV detection and genotyping, vaginal microbiome analysis, and STI-associated pathogen detection. The assay includes genotyping and detection of 14 hrHPV types, 5 low-risk HPV types (lrHPV), as well as the relative abundance of 31 bacterial taxa of clinical importance, including Lactobacillus, Sneathia, Gardnerella, and 3 pathogens involved in STI, with high sensitivity, specificity, and reproducibility. For each of these taxa, reference ranges were determined in a group of 50 self-reported healthy women. The HPV sequencing portion of the test was evaluated against the digene High-Risk HPV HC2 DNA test. For hrHPV genotyping, agreement was 95.3% with a kappa of 0.804 (601 samples); after removal of samples in which the digene hrHPV probe showed cross-reactivity with lrHPV types, the sensitivity and specificity of the hrHPV genotyping assay were 94.5% and 96.6%, respectively, with a kappa of 0.841. For lrHPV genotyping, agreement was 93.9% with a kappa of 0.788 (148 samples), while sensitivity and specificity were 100% and 92.9%, respectively. This novel assay could be used to complement conventional cervical cancer screening, because its self-sampling format can expand access among women who would otherwise not participate, and because of its additional information about the composition of the vaginal microbiome and the presence of pathogens., Competing Interests: All of the authors of the paper are current or past employees of uBiome, Inc. and have received stock options as well as other compensation. Some authors have patents pending in relation to this work: US Application No 15/198,818, Method and system for diagnostic testing, Application No 16/084,945, Method and system for microbiome-derived diagnostics and therapeutics for bacterial vaginosis, and Application No 16/115,542, Method and system for characterization for female reproductive system-related conditions associated with microorganisms. The data in this article were used in the development of a commercially available test product developed and marketed by uBiome. This does not alter our adherence to PLOS ONE policies on sharing data and materials.

Ineffective myelin debris clearance is a major factor contributing to the poor regenerative ability of the central nervous system. In stark contrast, rapid clearance of myelin debris from the injured peripheral nervous system (PNS) is one of the keys to this system's remarkable regenerative capacity, but the molecular mechanisms driving PNS myelin clearance are incompletely understood. We set out to discover new pathways of PNS myelin clearance to identify novel strategies for activating myelin clearance in the injured central nervous system, where myelin debris is not cleared efficiently. Here we show that Schwann cells, the myelinating glia of the PNS, collaborate with hematogenous macrophages to clear myelin debris using TAM (Tyro3, Axl, Mer) receptor-mediated phagocytosis as well as autophagy. In a mouse model of PNS nerve crush injury, Schwann cells up-regulate TAM phagocytic receptors Axl and Mertk following PNS injury, and Schwann cells lacking both of these phagocytic receptors exhibit significantly impaired myelin phagocytosis both in vitro and in vivo. Autophagy-deficient Schwann cells also display reductions in myelin clearance after mouse nerve crush injury, as has been recently shown following nerve transection. These findings add a mechanism, Axl/Mertk-mediated myelin clearance, to the repertoire of cellular machinery used to clear myelin in the injured PNS. Given recent evidence that astrocytes express Axl and Mertk and have previously unrecognized phagocytic potential, this pathway may be a promising avenue for activating myelin clearance after CNS injury., Competing Interests: The authors declare no conflict of interest.

Airborne N-nitrosomorpholine (0 to 27 micrograms per cubic meter) was found in two of four rubber industry factories. N-Nitrosodimethylamine was also found in two factories, but at lower levels. These findings may be relevant to the reported increased risk of certain types of cancer in rubber workers in some of the same areas where the N-nitrosomorpholine levels were highest.

We evaluated workers and performed an industrial hygiene assessment at a plant where raw eggs are processed into powdered egg yolk and whole egg. Egg dust levels in the packaging room straddled the American Conference of Governmental Industrial Hygienists' (ACGIH) exposure guideline of 10 mg/m3 for nuisance dust. We obtained medical histories from 25 workers, and performed physical examinations, spirometry, and serial determinations of peak expiratory flow rate (PEFR) by portable meter every 3 hrs (while awake) for 7 days. We defined symptomatic bronchial lability to be a decrement in PEFR on any one day of 20% or more of the day's maximum, with concurrent symptoms. Skin-prick tests and serum assays for specific IgE by the radioallergosorbent (RAST) method were performed to assess sensitivity to commercial egg proteins, egg protein fractions, and freshly prepared extracts of whole egg powder and yolk. We classified participants as definite cases of asthma if both the examining physician diagnosed asthma and symptomatic bronchial lability was demonstrated by serial PEFR determinations. Definite noncases of asthma were those participants in whom the physician did not diagnose asthma and in whom symptomatic bronchial lability was not demonstrated by PEFR. All five definite cases, compared to three of 16 definite noncases of asthma, had one or more positive skin-prick tests to egg proteins. Four of five cases, compared to 0 of 14 noncases, who had serum determinations, had an elevated RAST to one or more of the egg proteins. This study demonstrates that occupational asthma associated with IgE-mediated allergy to egg proteins occurs among workers exposed to inhaled egg proteins.