WAVE-DAMPENED2-LIKE4 modulates the hyper-elongation of light-grown hypocotyl cells.

Light, temperature, water, and nutrient availability influence how plants grow to maximize access to resources. Axial growth, the linear extension of tissues by coordinated axial cell expansion, plays a central role in these adaptive morphological responses. Using Arabidopsis (Arabidopsis thaliana) hypocotyl cells to explore axial growth control mechanisms, we investigated WAVE-DAMPENED2-LIKE4 (WDL4), an auxin-induced, microtubule-associated protein and member of the larger WDL gene family shown to modulate hypocotyl growth under changing environmental conditions. Loss-of-function wdl4 seedlings exhibited a hyper-elongation phenotype under light conditions, continuing to elongate when wild-type Col-0 hypocotyls arrested and reaching 150% to 200% of wild-type length before shoot emergence. wdl4 seedling hypocotyls showed dramatic hyper-elongation (500%) in response to temperature elevation, indicating an important role in morphological adaptation to environmental cues. WDL4 was associated with microtubules under both light and dark growth conditions, and no evidence was found for altered microtubule array patterning in loss-of-function wdl4 mutants under various conditions. Examination of hormone responses showed altered sensitivity to ethylene and evidence for changes in the spatial distribution of an auxin-dependent transcriptional reporter. Our data provide evidence that WDL4 regulates hypocotyl cell elongation without substantial changes to microtubule array patterning, suggesting an unconventional role in axial growth control.

Congenital Cytomegalovirus-Associated Sensorineural Hearing Loss in Children: Identification Following Universal Newborn Hearing Screening, Effect of Antiviral Treatment, and Long-Term Hearing Outcomes.

OBJECTIVES: Congenital cytomegalovirus (cCMV) is the most common cause of nongenetic sensorineural hearing loss (SNHL) in children. We examined the longitudinal hearing outcomes of children with cCMV in relation to their newborn hearing screening findings, and their use of antiviral therapy. DESIGN: The study was based on a retrospective chart review using a database of pediatric patients (N = 445) seen at the University of Minnesota Lions clinic. Chart review identified infants with cCMV, and records were reviewed for information about universal newborn hearing screen (UNHS) results, the clinical course of SNHL, and the use of antiviral therapy. RESULTS: A total of 44 children were identified with cCMV. In this group, 33 (75%) had SNHL of varying degree and age at onset. Notably, 17 (39%) children passed UNHS bilaterally. Of those children, 6 (35%) ultimately acquired bilateral or unilateral SNHL, detected at a mean age of 20 months (median age, 12 months). Five out of 10 children (50%) that did not pass UNHS in one ear acquired late-onset hearing loss in the contralateral ear, identified at a mean age of 24 months (median age, 4 months). Eleven (25%) children passed UNHS bilaterally and continued to demonstrate normal hearing in both ears at their most recent follow-up visit at a mean age of 19 months (SD, 18 months). Of the 33 children with cCMV and SNHL, 18 (55%) received antiviral medication (ganciclovir and/or valganciclovir). While, on average, both treated and untreated ears experienced a progression of hearing loss over time, the group that received antiviral treatment experienced less overall hearing change compared with the untreated group (baseline-adjusted expected mean difference, -10.5 dB; 95% confidence interval, -28.1 to 7.2 dB). CONCLUSIONS: Among children with cCMV included in this study who passed UNHS in both ears, 35% demonstrated delayed-onset SNHL. Notably, of those children who referred unilaterally, 50% later demonstrated SNHL in the contralateral ear. These findings have implications for audiological monitoring, and potentially antiviral therapy, of children with cCMV. As implementation of universal cCMV screening moves forward, a key aspect of follow-up will be appropriate long-term audiologic monitoring.

The everchanging Sky-Tower - an apparent giant.

For over a quarter-century, the Sky-Tower has dominated the skyline of Auckland Tamaki Makaurau. Despite its imposing height, observers anecdotally report odd fluctuations in how big it appears. From certain angles, it can look positively stumpy. Such misperceptions can be bewildering and perilous when it happens whilst driving. Here, we characterise this strange illusion in the hopes of better understanding its cause.

Mentoring to address differential attainment of international medical graduates in GP training.

INTRODUCTION: International Medical Graduates (IMGs) form an important and valued part of the United Kingdom's (UK) medical workforce but many experience difficult transitions into the National Health Service workforce. Mentoring could support IMGs as they transition into their role as General Practice (GP) trainees but there is a lack of evidence about whether mentoring is an effective intervention for this group. AIM: To evaluate the effectiveness of the NHS Education for Scotland (NES) GP mentoring programme from the perspective of mentors and mentees. METHOD: Twelve medical educators (the mentors) provided mentoring to 19 IMG GP trainees (the mentees) who were within their first six months of entering GP training in Scotland. Each mentee received four 60-minute mentoring sessions via video conferencing. RESULTS: Mentoring provided tailored support to assist IMG GP trainees' holistic transition into UK General Practice. Mentees appreciated talking to a non-supervisor, receiving non-judgemental support and protected time with a supportive listener to overcome challenges. This had a positive impact, even for those who did not anticipate the need for such support. Mentors supported diverse needs and tailored meetings, experiencing a distinct shift from previous supervisor roles. Their diverse experience enhanced their role and they developed new skills. CONCLUSION: Mentoring could provide significant support to IMG GP trainees but comes with certain challenges. Future research should evaluate the long-term impact of the NES GP IMG mentoring programme.

'Bitesize' primary care focused education programme for GP trainees in their hospital component: an evaluation of a national teaching pilot.

There is need for a greater connection between General Practice and GP trainees in their hospital component of training. Currently, in Scotland, there are no national education programmes specifically designed for GP trainees during their hospital component of training. Our aim was to develop and evaluate the feasibility of a national online 'bitesize' education programme delivered live for GP trainees in their hospital component of training. The study also aims to assess the barriers to attending these teaching sessions and whether they made trainees feel more connected to General Practice. Weekly one hour 'Bitesize' teaching sessions, delivered virtually, were organised by NHS Education for Scotland (NES) GP Medical Education Fellows during a four-week period. Eligible attendees were GP trainees (GPST1s and GPST2s) working in the hospital component of their training. An end of program questionnaire, gathering quantitative and qualitative data, was used for evaluation. There was a strong support for this programme from the attendance numbers and the questionnaire feedback responses, with GP trainees feeling more in touch with general practice and more confident in managing primary care focused topics. GP trainees agreed that a weekly, one-hour, online lunchtime session suits them. The most common barrier to attendance were work commitments and conflicts with local teaching. This pilot has emphasised the need for a structured teaching programme for GP trainees in the hospital component of training.

Formula Otorrhea in Pediatric Patients With Cleft Palate.

The case series details 2 unusual cases of male newborns with cleft lip and palate (CLP) that later developed formula otorrhea. Both patients underwent bilateral myringotomies with the insertion of pressure equalizing (PE) tubes for chronic otitis media with effusion (OME). Chronic otorrhea associated with feeding occurred post-PE tube insertion and the otorrhea was later confirmed to be due to reflux of formula. Patients were treated with antibiotic ear drops, routine ear cleaning, anti-reflux medication, and reflux precautions. After definite cleft palate repair, formula otorrhea completely resolved. When patients with CLP develop chronic OME or otorrhea following PE tube placement, reflux of formula into the middle ear should be considered and treated accordingly.

CRISPR screening using an expanded toolkit of autophagy reporters identifies TMEM41B as a novel autophagy factor.

The power of forward genetics in yeast is the foundation on which the field of autophagy research firmly stands. Complementary work on autophagy in higher eukaryotes has revealed both the deep conservation of this process, as well as novel mechanisms by which autophagy is regulated in the context of development, immunity, and neuronal homeostasis. The recent emergence of new clustered regularly interspaced palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9)-based technologies has begun facilitating efforts to define novel autophagy factors and pathways by forward genetic screening in mammalian cells. Here, we set out to develop an expanded toolkit of autophagy reporters amenable to CRISPR/Cas9 screening. Genome-wide screening of our reporters in mammalian cells recovered virtually all known autophagy-related (ATG) factors as well as previously uncharacterized factors, including vacuolar protein sorting 37 homolog A (VPS37A), transmembrane protein 251 (TMEM251), amyotrophic lateral sclerosis 2 (ALS2), and TMEM41B. To validate this data set, we used quantitative microscopy and biochemical analyses to show that 1 novel hit, TMEM41B, is required for phagophore maturation. TMEM41B is an integral endoplasmic reticulum (ER) membrane protein distantly related to the established autophagy factor vacuole membrane protein 1 (VMP1), and our data show that these two factors play related, albeit not fully overlapping, roles in autophagosome biogenesis. In sum, our work uncovers new ATG factors, reveals a malleable network of autophagy receptor genetic interactions, and provides a valuable resource (http://crispr.deniclab.com) for further mining of novel autophagy mechanisms.

ActiveDriverDB: human disease mutations and genome variation in post-translational modification sites of proteins.

Interpretation of genetic variation is needed for deciphering genotype-phenotype associations, mechanisms of inherited disease, and cancer driver mutations. Millions of single nucleotide variants (SNVs) in human genomes are known and thousands are associated with disease. An estimated 21% of disease-associated amino acid substitutions corresponding to missense SNVs are located in protein sites of post-translational modifications (PTMs), chemical modifications of amino acids that extend protein function. ActiveDriverDB is a comprehensive human proteo-genomics database that annotates disease mutations and population variants through the lens of PTMs. We integrated >385,000 published PTM sites with ∼3.6 million substitutions from The Cancer Genome Atlas (TCGA), the ClinVar database of disease genes, and human genome sequencing projects. The database includes site-specific interaction networks of proteins, upstream enzymes such as kinases, and drugs targeting these enzymes. We also predicted network-rewiring impact of mutations by analyzing gains and losses of kinase-bound sequence motifs. ActiveDriverDB provides detailed visualization, filtering, browsing and searching options for studying PTM-associated mutations. Users can upload mutation datasets interactively and use our application programming interface in pipelines. Integrative analysis of mutations and PTMs may help decipher molecular mechanisms of phenotypes and disease, as exemplified by case studies of TP53, BRCA2 and VHL. The open-source database is available at https://www.ActiveDriverDB.org.

Npas1+ Pallidal Neurons Target Striatal Projection Neurons.

UNLABELLED: Compelling evidence demonstrates that the external globus pallidus (GPe) plays a key role in processing sensorimotor information. An anatomical projection from the GPe to the dorsal striatum has been described for decades. However, the cellular target and functional impact of this projection remain unknown. Using cell-specific transgenic mice, modern monosynaptic tracing techniques, and optogenetics-based mapping, we discovered that GPe neurons provide inhibitory inputs to direct and indirect pathway striatal projection neurons (SPNs). Our results indicate that the GPe input to SPNs arises primarily from Npas1-expressing neurons and is strengthened in a chronic Parkinson's disease (PD) model. Alterations of the GPe-SPN input in a PD model argue for the critical position of this connection in regulating basal ganglia motor output and PD symptomatology. Finally, chemogenetic activation of Npas1-expressing GPe neurons suppresses motor output, arguing that strengthening of the GPe-SPN connection is maladaptive and may underlie the hypokinetic symptoms in PD. SIGNIFICANCE STATEMENT: An anatomical projection from the pallidum to the striatum has been described for decades, but little is known about its connectivity pattern. The authors dissect the presynaptic and postsynaptic neurons involved in this projection, and show its cell-specific remodeling and strengthening in parkinsonian mice. Chemogenetic activation of Npas1(+) pallidal neurons that give rise to the principal pallidostriatal projection increases the time that the mice spend motionless. This argues that maladaptive strengthening of this connection underlies the paucity of volitional movements, which is a hallmark of Parkinson's disease.

Tricellular Tight Junction Protein Tricellulin Is Targeted by the Enteropathogenic Escherichia coli Effector EspG1, Leading to Epithelial Barrier Disruption.

Enteropathogenic Escherichia coli (EPEC)-induced diarrhea is often associated with disruption of intestinal epithelial tight junctions. Although studies have shown alterations in the expression and localization of bicellular tight junction proteins during EPEC infections, little is known about whether tricellular tight junction proteins (tTJs) are affected. Using Caco-2 cell monolayers, we investigated if EPEC is capable of targeting the tTJ protein tricellulin. Our results demonstrated that at 4 h postinfection, EPEC induced a significant reduction in tricellulin levels, accompanied by a significant loss of transepithelial resistance (TEER) and a corresponding increase in paracellular permeability. Conversely, cells overexpressing tricellulin were highly resistant to EPEC-induced barrier disruption. Confocal microscopy revealed the distribution of tricellulin into the plasma membrane of infected epithelial cells and confirmed the localization of EPEC aggregates in close proximity to tTJs. Moreover, infections with EPEC strains lacking genes encoding specific type III secreted effector proteins demonstrated a crucial role for the effector EspG1 in modulating tricellulin expression. Complementation studies suggest that the EspG-induced depletion of tricellulin is microtubule dependent. Overall, our results show that EPEC-induced epithelial barrier dysfunction is mediated in part by EspG1-induced microtubule-dependent depletion of tricellulin.

Goblet Cell Derived RELM-ß Recruits CD4+ T Cells during Infectious Colitis to Promote Protective Intestinal Epithelial Cell Proliferation.

Enterohemorrhagic Escherichia coli and related food and waterborne pathogens pose significant threats to human health. These attaching/effacing microbes infect the apical surface of intestinal epithelial cells (IEC), causing severe diarrheal disease. Colonizing the intestinal luminal surface helps segregate these microbes from most host inflammatory responses. Based on studies using Citrobacter rodentium, a related mouse pathogen, we speculate that hosts rely on immune-mediated changes in IEC, including goblet cells to defend against these pathogens. These changes include a CD4+ T cell-dependent increase in IEC proliferation to replace infected IEC, as well as altered production of the goblet cell-derived mucin Muc2. Another goblet cell mediator, REsistin-Like Molecule (RELM)-ß is strongly induced within goblet cells during C. rodentium infection, and was detected in the stool as well as serum. Despite its dramatic induction, RELM-ß's role in host defense is unclear. Thus, wildtype and RELM-ß gene deficient mice (Retnlb-/-) were orally infected with C. rodentium. While their C. rodentium burdens were only modestly elevated, infected Retnlb-/- mice suffered increased mortality and mucosal ulceration due to deep pathogen penetration of colonic crypts. Immunostaining for Ki67 and BrDU revealed Retnlb-/- mice were significantly impaired in infection-induced IEC hyper-proliferation. Interestingly, exposure to RELM-ß did not directly increase IEC proliferation, rather RELM-ß acted as a CD4+ T cell chemoattractant. Correspondingly, Retnlb-/- mice showed impaired CD4+ T cell recruitment to their infected colons, along with reduced production of interleukin (IL)-22, a multifunctional cytokine that directly increased IEC proliferation. Enema delivery of RELM-ß to Retnlb-/- mice restored CD4+ T cell recruitment, concurrently increasing IL-22 levels and IEC proliferation, while reducing mucosal pathology. These findings demonstrate that RELM-ß and goblet cells play an unexpected, yet critical role in recruiting CD4+ T cells to the colon to protect against an enteric pathogen, in part via the induction of increased IEC proliferation.

Analysis of archived newborn dried blood spots (DBS) identifies congenital cytomegalovirus as a major cause of unexplained pediatric sensorineural hearing loss.

PURPOSE: Congenital cytomegalovirus (cCMV) infection is the most common non-genetic cause of sensorineural hearing loss (SNHL). However, accurate diagnosis of cCMV as the etiology of SNHL is problematic beyond the neonatal period. This study therefore examined whether cCMV infection could be identified retrospectively in children presenting with unexplained SNHL to a multidisciplinary diagnostic outpatient otolaryngology clinic at an academic medical center in Minnesota. METHODS: Over a 4-year period, 57 patients with an age range of 3months to 10years with unexplained SNHL were recruited to participate in this study. Informed consent was obtained to test the archived dried blood spots (DBS) of these patients for cCMV infection by real-time PCR, targeting a highly conserved region of the CMV UL83 gene. Results were normalized to recovery of an NRAS gene control. Chart review was conducted to identify subjects who underwent genetic testing and/or neurodiagnostic imaging to investigate possible genetic, syndromic, or anatomical causes of SNHL. RESULTS: In total, 15 of the 57 children with unexplained SNHL tested positive for CMV DNA in their DBS (26%). A mean viral load of 8.3×104 (±4.1×104) [range, 1×103-6×105] copies/µg DNA was observed in subjects retrospectively diagnosed with cCMV. No statistically significant correlation was found between viral load and SNHL severity. CONCLUSIONS: A retrospective DBS analysis demonstrated that 26% of patients presenting with unexplained SNHL in childhood had cCMV. DBS testing is useful in the retrospective diagnosis of cCMV, and may provide definitive diagnostic information about the etiology of SNHL.

Parvalbumin+ Neurons and Npas1+ Neurons Are Distinct Neuron Classes in the Mouse External Globus Pallidus.

Compelling evidence suggests that pathological activity of the external globus pallidus (GPe), a nucleus in the basal ganglia, contributes to the motor symptoms of a variety of movement disorders such as Parkinson's disease. Recent studies have challenged the idea that the GPe comprises a single, homogenous population of neurons that serves as a simple relay in the indirect pathway. However, we still lack a full understanding of the diversity of the neurons that make up the GPe. Specifically, a more precise classification scheme is needed to better describe the fundamental biology and function of different GPe neuron classes. To this end, we generated a novel multicistronic BAC (bacterial artificial chromosome) transgenic mouse line under the regulatory elements of the Npas1 gene. Using a combinatorial transgenic and immunohistochemical approach, we discovered that parvalbumin-expressing neurons and Npas1-expressing neurons in the GPe represent two nonoverlapping cell classes, amounting to 55% and 27% of the total GPe neuron population, respectively. These two genetically identified cell classes projected primarily to the subthalamic nucleus and to the striatum, respectively. Additionally, parvalbumin-expressing neurons and Npas1-expressing neurons were distinct in their autonomous and driven firing characteristics, their expression of intrinsic ion conductances, and their responsiveness to chronic 6-hydroxydopamine lesion. In summary, our data argue that parvalbumin-expressing neurons and Npas1-expressing neurons are two distinct functional classes of GPe neurons. This work revises our understanding of the GPe, and provides the foundation for future studies of its function and dysfunction. SIGNIFICANCE STATEMENT: Until recently, the heterogeneity of the constituent neurons within the external globus pallidus (GPe) was not fully appreciated. We addressed this knowledge gap by discovering two principal GPe neuron classes, which were identified by their nonoverlapping expression of the markers parvalbumin and Npas1. Our study provides evidence that parvalbumin and Npas1 neurons have different topologies within the basal ganglia.

Dietary vitamin D3 deficiency alters intestinal mucosal defense and increases susceptibility to Citrobacter rodentium-induced colitis.

Vitamin D deficiency affects more that 1 billion people worldwide. Although thought to increase risk of bacterial infections, the importance of vitamin D on host defense against intestinal bacterial pathogens is currently unclear since injection of the active form of vitamin D, 1,25(OH)2D3, increased susceptibility to the enteric bacterial pathogen Citrobacter rodentium by suppressing key immune/inflammatory factors. To further characterize the role of vitamin D during bacteria-induced colitis, we fed weanling mice either vitamin D3-deficient or vitamin D3-sufficient diets for 5 wk and then challenged them with C. rodentium. Vitamin D3-deficient mice lost significantly more body weight, carried higher C. rodentium burdens, and developed worsened histological damage. Vitamin D3-deficient mice also suffered greater bacterial translocation to extra-intestinal tissues, including mesenteric lymph nodes, spleen, and liver. Intestinal tissues of infected vitamin D3-deficient mice displayed increased inflammatory cell infiltrates as well as significantly higher gene transcript levels of inflammatory mediators TNF-α, IL-1ß, IL-6, TGF-ß, IL-17A, and IL-17F as well as the antimicrobial peptide REG3γ. Notably, these exaggerated inflammatory responses accelerated the loss of commensal microbes and were associated with an impaired ability to detoxify bacterial lipopolysaccharide. Overall, these studies show that dietary-induced vitamin D deficiency exacerbates intestinal inflammatory responses to infection, also impairing host defense.

3D printing of biomimetic microstructures for cancer cell migration.

To understand the physical behavior and migration of cancer cells, a 3D in vitro micro-chip in hydrogel was created using 3D projection printing. The micro-chip has a honeycomb branched structure, aiming to mimic 3D vascular morphology to test, monitor, and analyze differences in the behavior of cancer cells (i.e. HeLa) vs. non-cancerous cell lines (i.e. 10 T1/2). The 3D Projection Printing system can fabricate complex structures in seconds from user-created designs. The fabricated microstructures have three different channel widths of 25, 45, and 120 microns wide to reflect a range of blood vessel diameters. HeLa and 10 T1/2 cells seeded within the micro-chip were then analyzed for morphology and cell migration speed. 10 T1/2 cells exhibited greater changes in morphology due to channel size width than HeLa cells; however, channel width had a limited effect on 10 T1/2 cell migration while HeLa cancer cell migration increased as channel width decreased. This physiologically relevant 3D cancer tissue model has the potential to be a powerful tool for future drug discoveries and cancer migration studies.

Pathogenic Potential of Turicella otitidis and Staphylococcus auricularis: A Case Report.

Objective: Turicella otitidis and Staphylococcus auricularis have been considered normal aural flora. Their significance in active infection is controversial. We examined a series of patients presenting with acute and chronic otitis media whose ear canal culture isolated T. otitidis and S. auricularis and explored possible pathogenicity, associated factors, and outcomes. Methods: This is a retrospective chart review of patients who presented to a tertiary center outpatient clinic between 2017 and 2022 with otologic microscopic examination of active infection and ear canal culture isolating T. otitidis or S. auricularis only. Clinical course was collected including history, microscopic otoscopy findings, interventions given, outcomes, and sensitivity results. Results: A total of 13 patients (10 with T. otitidis and 3 with S. auricularis) were included. Majority of the patients had a history of otologic surgery (92%) and tympanic membrane perforation (62%). All were treated with combinations of antibiotic otic drops (ie, fluoroquinolone, sulfa, or aminoglycoside based) ± oral antibiotics (ie, penicillin or trimethoprim/sulfamethoxazole). Otorrhea resolved among majority of patients. Otorrhea and mucosalization returned or continued among 4 patients. Sensitivity results demonstrated that 2 of 3 strains of T. otitidis were resistant to clindamycin. There was no resistance against S. auricularis for tested antibiotics. Conclusions: Our findings suggest the potential pathogenicity of T. otitidis and S. auricularis, especially among patients with prior ear surgery and tympanic membrane perforation. Violation of the epithelial barrier from surgery or trauma may contribute to their pathogenicity. Future study is warranted to elucidate pathogenicity of normal aural flora and its mechanisms.

Magnetic Resonancy Imaging Safety in Active Osseointegrated (Osia®) and Cochlear Implants: New Technology Creating Confusion.

OBJECTIVE: There is increased confusion regarding MRI-compatible CIs and BAHAs. This report describes two cases when patients underwent MRIs with non-MRI compatible devices. RESULTS: One patient with bilateral Cochlear Osias experienced dislocation of both internal magnets after 1.5 Tesla MRI. Both magnets were outside the silastic sheath, with the left magnet flipped. A second patient with a legacy CI experienced similar internal magnet dislocation and inversion after 3 Tesla MRI. CONCLUSIONS: This study describes internal magnet dislocation/inversion with the Cochlear Osia and a legacy CI after MRI. Our findings suggest the need for improved patient education and simplified radiology guidelines. Laryngoscope, 134:393-396, 2024.

Association of Sleep Characteristics with Tinnitus and Hearing Loss.

Objective: The impact of poor sleep on tinnitus has been mainly attributed to central processes. There is an association between sleep disorders and hearing loss, but whether hearing levels mediate the association between sleep disorders and tinnitus is unknown. This study investigates the association between sleep characteristics, tinnitus, and hearing loss. Study Design: Cross-sectional. Setting: National Health and Nutrition Examination Survey (NHANES). Methods: Study cohort includes 9693 adults (≥20 years) from the NHANES 2005 to 2018 who completed audiometric testing and questionnaires on tinnitus and sleep characteristics. Multivariable regression analyses were performed to quantify associations between sleep characteristics, tinnitus, and hearing loss. Results: In this cohort, 29% (95% confidence interval [CI]: 28%-31%) reported trouble sleeping and 9% (95% CI: 8%-10%) reported being diagnosed with sleep disorders. Negative sleep characteristics (less hours of sleep, diagnosis of a sleep disorder, trouble sleeping, or OSA symptoms) were not associated with audiometry-measured hearing loss in multivariable models adjusted for demographics and comorbidities but were significantly associated with bothersome tinnitus. This association remained significant without substantial attenuation in multivariable models additionally adjusting for hearing levels: sleeping <8 h/day (vs ≥8) (odds ratio [OR]: 1.28 [95% CI: 1.08-1.52]), trouble sleeping (OR: 1.78 [95% CI: 1.45-2.19]), diagnosis of sleep disorders (OR: 1.57 [95% CI: 1.14-2.15]), and report of OSA symptoms (OR: 1.42 [95% CI: 1.08-1.88]). Conclusion: Negative sleep characteristics were associated with tinnitus while there was no clinically meaningful association between sleep and hearing loss. Our findings suggest that the relationship between poor sleep and tinnitus is likely contributed by central processes without a major role of mediation via the peripheral auditory system.

Hypoxia-inducible factor 1 recruits FACT and RNF20/40 to mediate histone ubiquitination and transcriptional activation of target genes.

Hypoxia-inducible factor 1 (HIF-1) is a transcriptional activator that mediates cellular adaptation to decreased oxygen availability. HIF-1 recruits chromatin-modifying enzymes leading to changes in histone acetylation, citrullination, and methylation at target genes. Here, we demonstrate that hypoxia-inducible gene expression in estrogen receptor (ER)-positive MCF7 and ER-negative SUM159 human breast cancer cells requires the histone H2A/H2B chaperone facilitates chromatin transcription (FACT) and the H2B ubiquitin ligase RING finger protein 20/40 (RNF20/40). Knockdown of FACT or RNF20/40 expression leads to decreased transcription initiation and elongation at HIF-1 target genes. Mechanistically, FACT and RNF20/40 are recruited to hypoxia response elements (HREs) by HIF-1 and stabilize binding of HIF-1 (and each other) at HREs. Hypoxia induces the monoubiquitination of histone H2B at lysine 120 at HIF-1 target genes in an HIF-1-dependent manner. Together, these findings delineate a cooperative molecular mechanism by which FACT and RNF20/40 stabilize multiprotein complex formation at HREs and mediate histone ubiquitination to facilitate HIF-1 transcriptional activity.

The mucin Muc2 limits pathogen burdens and epithelial barrier dysfunction during Salmonella enterica serovar Typhimurium colitis.

Salmonella enterica serovar Typhimurium is a model organism used to explore the virulence strategies underlying Salmonella pathogenesis. Although intestinal mucus is the first line of defense in the intestine, its role in protection against Salmonella is still unclear. The intestinal mucus layer is composed primarily of the Muc2 mucin, a heavily O-glycosylated glycoprotein. The core 3-derived O-glycans of Muc2 are synthesized by core 3 ß1,3-N-acetylglucosaminyltransferase (C3GnT). Mice lacking these glycans still produce Muc2 but display a thinner intestinal mucus barrier. We began our investigations by comparing Salmonella-induced colitis and mucus dynamics in Muc2-deficient (Muc2(-/-)) mice, C3GnT(-/-) mice, and wild-type C57BL/6 (WT) mice. Salmonella infection led to increases in luminal Muc2 secretion in WT and C3GnT(-/-) mice. When Muc2(-/-) mice were infected with Salmonella, they showed dramatic susceptibility to infection, carrying significantly higher cecal and liver pathogen burdens, and developing significantly higher barrier disruption and higher mortality rates, than WT mice. We found that the exaggerated barrier disruption in infected Muc2(-/-) mice was invA dependent. We also tested the susceptibility of C3GnT(-/-) mice and found that they carried pathogen burdens similar to those of WT mice but developed exaggerated barrier disruption. Moreover, we found that Muc2(-/-) mice were impaired in intestinal alkaline phosphatase (IAP) expression and lipopolysaccharide (LPS) detoxification activity in their ceca, potentially explaining their high mortality rates during infection. Our data suggest that the intestinal mucus layer (Muc2) and core 3 O-glycosylation play critical roles in controlling Salmonella intestinal burdens and intestinal epithelial barrier function, respectively.