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New Version of PubMed Central® Journal List Released

PMC released a new and improved journal list on March 31, 2009, after a comprehensive redesign for greater clarity and organization.

The new design not only combines the full-list and tabbed-list views of the previous version but also includes some new or updated features to provide users with a greater overview of the total PMC archive. Looking at this new list, you will find:

  1. An Expanded View of PMC journals that includes NIH Portfolio
  2. Special Collections
  3. A New “Participation Level” Journal Category
  4. Hide/Show Display Option for Predecessor Titles
  5. Article and Journal Search Feature

For more information, see the complete article in the May-June issue of the NLM Technical Bulletin: https://www.nlm.nih.gov/pubs/techbull/mj09/mj09_pmc_redesign.html




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New Search Function Released

You can now find embargoed articles and their corresponding PMCIDs through a recently released search option in the PMC Entrez database. Using the “Limits” tab, click in the field, “Show both free and embargoed articles” and refine your search by journal, author, date, article type, and/or tag term, as needed. Once you’re on the summary page, click on the “embargoed” tab at the top to find the articles in this category. You can then find the PMCID and date of availability at the bottom of the article citation, as indicated in the example below. Note: The PMC search option only includes articles with an initial embargo of up to 12 months. Articles with an embargo greater than 12 months are not compliant with the NIH Public Access Policy and will appear in search results only when the full text is free in PMC. For more information, see the article in the September-October issue of the NLM Technical Bulletin.




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New Version of PMC Help is Released

The PMC user's guide, PMC Help has been updated to include new and improved information on navigating the site as well as descriptions and instructions on using the new search functions, such as Limits and Advanced Search Builder. Further updates will also be forthcoming.




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New Version of PubReader is Released

PMC has recently released an updated version of its PubReader view. The new version (1.2) includes a "search this page" feature that allows you to find specific terms within the article. The latest source code is also available from the GitHub repository.




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PMC Releases New ID Converter

PMC has just released an upgrade to our ID converter, now dubbed the PMCID - PMID -Manuscript ID - DOI Converter. This utility allows you to start with the unique identifier for an article that is in PMC, and find additional unique identifiers that may apply to the article. Improvements include support for DOIs, auto-detection of the ID type based on its format, and enhanced output. It also provides output in any of several different formats: HTML, XML, JSON, or CSV. This tool uses an underlying web service, that is also publicly available for those needing programmatic access to this data. See the ID Converter API documentation.




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Updated information on journal selection and participation agreements released

PMC has released expanded information about its selection process for journals that apply for participation. The current review process has been in place since November 2014 and focuses on the scientific rigor and editorial quality of each journal that applies to participate in PMC. Some of the attributes taken into account as part of this process include the article content, journal policies, language quality, and presentation of content. The same assessment considerations are used for reevaluation of currently participating journals. We encourage you to visit the Journal Selection for PMC page to learn more.

Publishers and journals interested in submitting an application to PMC are also encouraged to review our updated policies on agreement types. These policies provide the eligibility criteria for each type of participation agreement and should be considered alongside the pre-application requirements.

We hope these updates are informative and look forward to hearing your feedback.




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Peyronie's Disease (Curvature of the Penis)

Title: Peyronie's Disease (Curvature of the Penis)
Category: Diseases and Conditions
Created: 11/14/2002 12:00:00 AM
Last Editorial Review: 12/5/2019 12:00:00 AM




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Fabry Disease

Title: Fabry Disease
Category: Diseases and Conditions
Created: 12/31/1997 12:00:00 AM
Last Editorial Review: 4/2/2020 12:00:00 AM




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Sublocade (buprenorphine extended release)

Title: Sublocade (buprenorphine extended release)
Category: Medications
Created: 4/17/2020 12:00:00 AM
Last Editorial Review: 4/17/2020 12:00:00 AM




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Some NFL Players May Be Misdiagnosed With Brain Disease: Study

Title: Some NFL Players May Be Misdiagnosed With Brain Disease: Study
Category: Health News
Created: 4/27/2020 12:00:00 AM
Last Editorial Review: 4/28/2020 12:00:00 AM




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Welcome to the 'Smart Toilet' That Can Spot Disease

Title: Welcome to the 'Smart Toilet' That Can Spot Disease
Category: Health News
Created: 4/17/2020 12:00:00 AM
Last Editorial Review: 4/17/2020 12:00:00 AM




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The grease trap: uncovering the mechanism of the hydrophobic lid in Cutibacterium acnes lipase [Research Articles]

Acne is one of the most common dermatological conditions, but the details of its pathology are unclear, and current management regimens often have adverse effects. Cutibacterium acnes is known as a major acne-associated bacterium that derives energy from lipase-mediated sebum lipid degradation. C. acnes is commensal, but lipase activity has been observed to differ among C. acnes types. For example, higher populations of the type IA strains are present in acne lesions with higher lipase activity. In the present study, we examined a conserved lipase in types IB and II that was truncated in type IA C. acnes strains. Closed, blocked, and open structures of C. acnes ATCC11828 lipases were elucidated by X-ray crystallography at 1.6–2.4 Å. The closed crystal structure, which is the most common form in aqueous solution, revealed that a hydrophobic lid domain shields the active site. By comparing closed, blocked, and open structures, we found that the lid domain-opening mechanisms of C. acnes lipases (CAlipases) involve the lid-opening residues, Phe-179 and Phe-211. To the best of our knowledge, this is the first structure-function study of CAlipases, which may help to shed light on the mechanisms involved in acne development and may aid in future drug design.




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Vitamin E does not prevent Western diet-induced NASH progression and increases metabolic flux dysregulation in mice [Research Articles]

Fatty liver involves ectopic lipid accumulation and dysregulated hepatic oxidative metabolism, which can progress to a state of elevated inflammation and fibrosis referred to as nonalcoholic steatohepatitis (NASH). The factors that control progression from simple steatosis to NASH are not fully known. Here, we tested the hypothesis that dietary vitamin E (VitE) supplementation would prevent NASH progression and associated metabolic alterations induced by a Western diet (WD). Hyperphagic melanocortin-4 receptor-deficient (MC4R–/–) mice were fed chow, chow+VitE, WD, or WD+VitE starting at 8 or 20 weeks of age. All groups exhibited extensive hepatic steatosis by the end of the study (28 weeks of age). WD feeding exacerbated liver disease severity without inducing proportional changes in liver triglycerides. Eight weeks of WD accelerated liver pyruvate cycling, and 20 weeks of WD extensively upregulated liver glucose and oxidative metabolism assessed by 2H/13C flux analysis. VitE supplementation failed to reduce the histological features of NASH. Rather, WD+VitE increased the abundance and saturation of liver ceramides and accelerated metabolic flux dysregulation compared with 8 weeks of WD alone. In summary, VitE did not limit NASH pathogenesis in genetically obese mice, but instead increased some indicators of metabolic dysfunction.




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Myeloid-specific deficiency of pregnane X receptor decreases atherosclerosis in LDL receptor-deficient mice [Research Articles]

The pregnane X receptor (PXR) is a nuclear receptor that can be activated by numerous drugs and xenobiotic chemicals. PXR thereby functions as a xenobiotic sensor to coordinately regulate host responses to xenobiotics by transcriptionally regulating many genes involved in xenobiotic metabolism. We have previously reported that PXR has pro-atherogenic effects in animal models, but how PXR contributes to atherosclerosis development in different tissues or cell types remains elusive. In this study, we generated an LDL receptor-deficient mouse model with myeloid-specific PXR deficiency (PXRMyeLDLR–/–) to elucidate the role of macrophage PXR signaling in atherogenesis. The myeloid PXR deficiency did not affect metabolic phenotypes and plasma lipid profiles, but PXRMyeLDLR–/– mice had significantly decreased atherosclerosis at both aortic root and brachiocephalic arteries compared with control littermates. Interestingly, the PXR deletion did not affect macrophage adhesion and migration properties, but reduced lipid accumulation and foam cell formation in the macrophages. PXR deficiency also led to decreased expression of the scavenger receptor CD36 and impaired lipid uptake in macrophages of the PXRMyeLDLR–/– mice. Further, RNA-Seq analysis indicated that treatment with a prototypical PXR ligand affects the expression of many atherosclerosis-related genes in macrophages in vitro. These findings reveal a pivotal role of myeloid PXR signaling in atherosclerosis development and suggest that PXR may be a potential therapeutic target in atherosclerosis management.




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Hematopoiesis is regulated by cholesterol efflux pathways and lipid rafts: connections with cardiovascular diseases [Thematic Reviews]

Lipid rafts are highly ordered regions of the plasma membrane that are enriched in cholesterol and sphingolipids and play important roles in many cells. In hematopoietic stem and progenitor cells (HSPCs), lipid rafts house receptors critical for normal hematopoiesis. Lipid rafts also can bind and sequester kinases that induce negative feedback pathways to limit proliferative cytokine receptor cycling back to the cell membrane. Modulation of lipid rafts occurs through an array of mechanisms, with optimal cholesterol efflux one of the major regulators. As such, cholesterol homeostasis also regulates hematopoiesis. Increased lipid raft content, which occurs in response to changes in cholesterol efflux in the membrane, can result in prolonged receptor occupancy in the cell membrane and enhanced signaling. In addition, certain diseases, like diabetes, may contribute to lipid raft formation and affect cholesterol retention in rafts. In this review, we explore the role of lipid raft-related mechanisms in hematopoiesis and CVD (specifically, atherosclerosis) and discuss how defective cholesterol efflux pathways in HSPCs contribute to expansion of lipid rafts, thereby promoting myelopoiesis and thrombopoiesis. We also discuss the utility of cholesterol acceptors in contributing to lipid raft regulation and disruption, and highlight the potential to manipulate these pathways for therapeutic gain in CVD as well as other disorders with aberrant hematopoiesis.




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Lipid rafts and neurodegeneration: structural and functional roles in physiologic aging and neurodegenerative diseases [Thematic Reviews]

Lipid rafts are small, dynamic membrane areas characterized by the clustering of selected membrane lipids as the result of the spontaneous separation of glycolipids, sphingolipids, and cholesterol in a liquid-ordered phase. The exact dynamics underlying phase separation of membrane lipids in the complex biological membranes are still not fully understood. Nevertheless, alterations in the membrane lipid composition affect the lateral organization of molecules belonging to lipid rafts. Neural lipid rafts are found in brain cells, including neurons, astrocytes, and microglia, and are characterized by a high enrichment of specific lipids depending on the cell type. These lipid rafts seem to organize and determine the function of multiprotein complexes involved in several aspects of signal transduction, thus regulating the homeostasis of the brain. The progressive decline of brain performance along with physiological aging is at least in part associated with alterations in the composition and structure of neural lipid rafts. In addition, neurodegenerative conditions, such as lysosomal storage disorders, multiple sclerosis, and Parkinson’s, Huntington’s, and Alzheimer’s diseases, are frequently characterized by dysregulated lipid metabolism, which in turn affects the structure of lipid rafts. Several events underlying the pathogenesis of these diseases appear to depend on the altered composition of lipid rafts. Thus, the structure and function of lipid rafts play a central role in the pathogenesis of many common neurodegenerative diseases.




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Collaborative Cross Mice Yield Genetic Modifiers for Pseudomonas aeruginosa Infection in Human Lung Disease

ABSTRACT

Human genetics influence a range of pathological and clinical phenotypes in respiratory infections; however, the contributions of disease modifiers remain underappreciated. We exploited the Collaborative Cross (CC) mouse genetic-reference population to map genetic modifiers that affect the severity of Pseudomonas aeruginosa lung infection. Screening for P. aeruginosa respiratory infection in a cohort of 39 CC lines exhibits distinct disease phenotypes ranging from complete resistance to lethal disease. Based on major changes in the survival times, a quantitative-trait locus (QTL) was mapped on murine chromosome 3 to the genomic interval of Mb 110.4 to 120.5. Within this locus, composed of 31 protein-coding genes, two candidate genes, namely, dihydropyrimidine dehydrogenase (Dpyd) and sphingosine-1-phosphate receptor 1 (S1pr1), were identified according to the level of genome-wide significance and disease gene prioritization. Functional validation of the S1pr1 gene by pharmacological targeting in C57BL/6NCrl mice confirmed its relevance in P. aeruginosa pathophysiology. However, in a cohort of Canadian patients with cystic fibrosis (CF) disease, regional genetic-association analysis of the syntenic human locus on chromosome 1 (Mb 97.0 to 105.0) identified two single-nucleotide polymorphisms (rs10875080 and rs11582736) annotated to the Dpyd gene that were significantly associated with age at first P. aeruginosa infection. Thus, there is evidence that both genes might be implicated in this disease. Our results demonstrate that the discovery of murine modifier loci may generate information that is relevant to human disease progression.

IMPORTANCE Respiratory infection caused by P. aeruginosa is one of the most critical health burdens worldwide. People affected by P. aeruginosa infection include patients with a weakened immune system, such as those with cystic fibrosis (CF) genetic disease or non-CF bronchiectasis. Disease outcomes range from fatal pneumonia to chronic life-threatening infection and inflammation leading to the progressive deterioration of pulmonary function. The development of these respiratory infections is mediated by multiple causes. However, the genetic factors underlying infection susceptibility are poorly known and difficult to predict. Our study employed novel approaches and improved mouse disease models to identify genetic modifiers that affect the severity of P. aeruginosa lung infection. We identified candidate genes to enhance our understanding of P. aeruginosa infection in humans and provide a proof of concept that could be exploited for other human pathologies mediated by bacterial infection.




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Global Transcriptome Analysis Identifies a Diagnostic Signature for Early Disseminated Lyme Disease and Its Resolution

ABSTRACT

A bioinformatics approach was employed to identify transcriptome alterations in the peripheral blood mononuclear cells of well-characterized human subjects who were diagnosed with early disseminated Lyme disease (LD) based on stringent microbiological and clinical criteria. Transcriptomes were assessed at the time of presentation and also at approximately 1 month (early convalescence) and 6 months (late convalescence) after initiation of an appropriate antibiotic regimen. Comparative transcriptomics identified 335 transcripts, representing 233 unique genes, with significant alterations of at least 2-fold expression in acute- or convalescent-phase blood samples from LD subjects relative to healthy donors. Acute-phase blood samples from LD subjects had the largest number of differentially expressed transcripts (187 induced, 54 repressed). This transcriptional profile, which was dominated by interferon-regulated genes, was sustained during early convalescence. 6 months after antibiotic treatment the transcriptome of LD subjects was indistinguishable from that of healthy controls based on two separate methods of analysis. Return of the LD expression profile to levels found in control subjects was concordant with disease outcome; 82% of subjects with LD experienced at least one symptom at the baseline visit compared to 43% at the early convalescence time point and only a single patient (9%) at the 6-month convalescence time point. Using the random forest machine learning algorithm, we developed an efficient computational framework to identify sets of 20 classifier genes that discriminated LD from other bacterial and viral infections. These novel LD biomarkers not only differentiated subjects with acute disseminated LD from healthy controls with 96% accuracy but also distinguished between subjects with acute and resolved (late convalescent) disease with 97% accuracy.

IMPORTANCE Lyme disease (LD), caused by Borrelia burgdorferi, is the most common tick-borne infectious disease in the United States. We examined gene expression patterns in the blood of individuals with early disseminated LD at the time of diagnosis (acute) and also at approximately 1 month and 6 months following antibiotic treatment. A distinct acute LD profile was observed that was sustained during early convalescence (1 month) but returned to control levels 6 months after treatment. Using a computer learning algorithm, we identified sets of 20 classifier genes that discriminate LD from other bacterial and viral infections. In addition, these novel LD biomarkers are highly accurate in distinguishing patients with acute LD from healthy subjects and in discriminating between individuals with active and resolved infection. This computational approach offers the potential for more accurate diagnosis of early disseminated Lyme disease. It may also allow improved monitoring of treatment efficacy and disease resolution.




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Glycemic Variability in Diabetes Increases the Severity of Influenza

ABSTRACT

People with diabetes are two times more likely to die from influenza than people with no underlying medical condition. The mechanisms underlying this susceptibility are poorly understood. In healthy individuals, small and short-lived postprandial peaks in blood glucose levels occur. In diabetes mellitus, these fluctuations become greater and more frequent. This glycemic variability is associated with oxidative stress and hyperinflammation. However, the contribution of glycemic variability to the pathogenesis of influenza A virus (IAV) has not been explored. Here, we used an in vitro model of the pulmonary epithelial-endothelial barrier and novel murine models to investigate the role of glycemic variability in influenza severity. In vitro, a history of glycemic variability significantly increased influenza-driven cell death and destruction of the epithelial-endothelial barrier. In vivo, influenza virus-infected mice with a history of glycemic variability lost significantly more body weight than mice with constant blood glucose levels. This increased disease severity was associated with markers of oxidative stress and hyperinflammation both in vitro and in vivo. Together, these results provide the first indication that glycemic variability may help drive the increased risk of severe influenza in people with diabetes mellitus.

IMPORTANCE Every winter, people with diabetes are at increased risk of severe influenza. At present, the mechanisms that cause this increased susceptibility are unclear. Here, we show that the fluctuations in blood glucose levels common in people with diabetes are associated with severe influenza. These data suggest that glycemic stability could become a greater clinical priority for patients with diabetes during outbreaks of influenza.




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Erratum for Dai et al., "Autoantibody-Mediated Erythrophagocytosis Increases Tuberculosis Susceptibility in HIV Patients"




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Avoiding Drug Resistance by Substrate Envelope-Guided Design: Toward Potent and Robust HCV NS3/4A Protease Inhibitors

ABSTRACT

Hepatitis C virus (HCV) infects millions of people worldwide, causing chronic liver disease that can lead to cirrhosis, hepatocellular carcinoma, and liver transplant. In the last several years, the advent of direct-acting antivirals, including NS3/4A protease inhibitors (PIs), has remarkably improved treatment outcomes of HCV-infected patients. However, selection of resistance-associated substitutions and polymorphisms among genotypes can lead to drug resistance and in some cases treatment failure. A proactive strategy to combat resistance is to constrain PIs within evolutionarily conserved regions in the protease active site. Designing PIs using the substrate envelope is a rational strategy to decrease the susceptibility to resistance by using the constraints of substrate recognition. We successfully designed two series of HCV NS3/4A PIs to leverage unexploited areas in the substrate envelope to improve potency, specifically against resistance-associated substitutions at D168. Our design strategy achieved better resistance profiles over both the FDA-approved NS3/4A PI grazoprevir and the parent compound against the clinically relevant D168A substitution. Crystallographic structural analysis and inhibition assays confirmed that optimally filling the substrate envelope is critical to improve inhibitor potency while avoiding resistance. Specifically, inhibitors that enhanced hydrophobic packing in the S4 pocket and avoided an energetically frustrated pocket performed the best. Thus, the HCV substrate envelope proved to be a powerful tool to design robust PIs, offering a strategy that can be translated to other targets for rational design of inhibitors with improved potency and resistance profiles.

IMPORTANCE Despite significant progress, hepatitis C virus (HCV) continues to be a major health problem with millions of people infected worldwide and thousands dying annually due to resulting complications. Recent antiviral combinations can achieve >95% cure, but late diagnosis, low access to treatment, and treatment failure due to drug resistance continue to be roadblocks against eradication of the virus. We report the rational design of two series of HCV NS3/4A protease inhibitors with improved resistance profiles by exploiting evolutionarily constrained regions of the active site using the substrate envelope model. Optimally filling the S4 pocket is critical to avoid resistance and improve potency. Our results provide drug design strategies to avoid resistance that are applicable to other quickly evolving viral drug targets.




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A Virus Hosted in Malaria-Infected Blood Protects against T Cell-Mediated Inflammatory Diseases by Impairing DC Function in a Type I IFN-Dependent Manner

ABSTRACT

Coinfections shape immunity and influence the development of inflammatory diseases, resulting in detrimental or beneficial outcome. Coinfections with concurrent Plasmodium species can alter malaria clinical evolution, and malaria infection itself can modulate autoimmune reactions. Yet, the underlying mechanisms remain ill defined. Here, we demonstrate that the protective effects of some rodent malaria strains on T cell-mediated inflammatory pathologies are due to an RNA virus cohosted in malaria-parasitized blood. We show that live and extracts of blood parasitized by Plasmodium berghei K173 or Plasmodium yoelii 17X YM, protect against P. berghei ANKA-induced experimental cerebral malaria (ECM) and myelin oligodendrocyte glycoprotein (MOG)/complete Freund’s adjuvant (CFA)-induced experimental autoimmune encephalomyelitis (EAE), and that protection is associated with a strong type I interferon (IFN-I) signature. We detected the presence of the RNA virus lactate dehydrogenase-elevating virus (LDV) in the protective Plasmodium stabilates and we established that LDV infection alone was necessary and sufficient to recapitulate the protective effects on ECM and EAE. In ECM, protection resulted from an IFN-I-mediated reduction in the abundance of splenic conventional dendritic cell and impairment of their ability to produce interleukin (IL)-12p70, leading to a decrease in pathogenic CD4+ Th1 responses. In EAE, LDV infection induced IFN-I-mediated abrogation of IL-23, thereby preventing the differentiation of granulocyte-macrophage colony-stimulating factor (GM-CSF)-producing encephalitogenic CD4+ T cells. Our work identifies a virus cohosted in several Plasmodium stabilates across the community and deciphers its major consequences on the host immune system. More generally, our data emphasize the importance of considering contemporaneous infections for the understanding of malaria-associated and autoimmune diseases.

IMPORTANCE Any infection modifies the host immune status, potentially ameliorating or aggravating the pathophysiology of a simultaneous inflammatory condition. In the course of investigating how malaria infection modulates the severity of contemporaneous inflammatory diseases, we identified a nonpathogenic mouse virus in stabilates of two widely used rodent parasite lines: Plasmodium berghei K173 and Plasmodium yoelii 17X YM. We established that the protective effects of these Plasmodium lines on cerebral malaria and multiple sclerosis are exclusively due to this virus. The virus induces a massive type I interferon (IFN-I) response and causes quantitative and qualitative defects in the ability of dendritic cells to promote pathogenic T cell responses. Beyond revealing a possible confounding factor in rodent malaria models, our work uncovers some bases by which a seemingly innocuous viral (co)infection profoundly changes the immunopathophysiology of inflammatory diseases.




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YejM Modulates Activity of the YciM/FtsH Protease Complex To Prevent Lethal Accumulation of Lipopolysaccharide

ABSTRACT

Lipopolysaccharide (LPS) is an essential glycolipid present in the outer membrane (OM) of many Gram-negative bacteria. Balanced biosynthesis of LPS is critical for cell viability; too little LPS weakens the OM, while too much LPS is lethal. In Escherichia coli, this balance is maintained by the YciM/FtsH protease complex, which adjusts LPS levels by degrading the LPS biosynthesis enzyme LpxC. Here, we provide evidence that activity of the YciM/FtsH protease complex is inhibited by the essential protein YejM. Using strains in which LpxC activity is reduced, we show that yciM is epistatic to yejM, demonstrating that YejM acts upstream of YciM to prevent toxic overproduction of LPS. Previous studies have shown that this toxicity can be suppressed by deleting lpp, which codes for a highly abundant OM lipoprotein. It was assumed that deletion of lpp restores lipid balance by increasing the number of acyl chains available for glycerophospholipid biosynthesis. We show that this is not the case. Rather, our data suggest that preventing attachment of lpp to the peptidoglycan sacculus allows excess LPS to be shed in vesicles. We propose that this loss of OM material allows continued transport of LPS to the OM, thus preventing lethal accumulation of LPS within the inner membrane. Overall, our data justify the commitment of three essential inner membrane proteins to avoid toxic over- or underproduction of LPS.

IMPORTANCE Gram-negative bacteria are encapsulated by an outer membrane (OM) that is impermeable to large and hydrophobic molecules. As such, these bacteria are intrinsically resistant to several clinically relevant antibiotics. To better understand how the OM is established or maintained, we sought to clarify the function of the essential protein YejM in Escherichia coli. Here, we show that YejM inhibits activity of the YciM/FtsH protease complex, which regulates synthesis of the essential OM glycolipid lipopolysaccharide (LPS). Our data suggest that disrupting proper communication between LPS synthesis and transport to the OM leads to accumulation of LPS within the inner membrane (IM). The lethality associated with this event can be suppressed by increasing OM vesiculation. Our research has identified a completely novel signaling pathway that we propose coordinates LPS synthesis and transport.




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To bend with ease, take care of your knees

At some point during your life, it’s likely you’ll experience problems with your knees. Knees play an important role in helping us walk and bend, which means that they’re frequently in use. And like all parts of our bodies, sometimes they can wear out or be injured.




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Levodopa-induced dyskinesia in dementia with Lewy bodies and Parkinson disease with dementia

Objective

To investigate the frequency of levodopa-induced dyskinesia in dementia with Lewy bodies (DLBs) and Parkinson disease with dementia (PDD) and compare these frequencies with patients with incident Parkinson disease (PD) through a population-based cohort study.

Methods

We identified all patients with DLB, PDD, and PD without dementia in a 1991–2010 population-based parkinsonism-incident cohort, in Olmsted County, Minnesota. We abstracted information about levodopa-induced dyskinesia. We compared patients with DLB and PDD with dyskinesia with patients with PD from the same cohort.

Results

Levodopa use and dyskinesia data were available for 141/143 (98.6%) patients with a diagnosis of either DLB or PDD; 87 (61.7%), treated with levodopa. Dyskinesia was documented in 12.6% (8 DLB and 3 PDD) of levodopa-treated patients. Among these patients, median parkinsonism diagnosis age was 74 years (range: 64–80 years); 63.6%, male. The median interval from levodopa initiation to dyskinesia onset was 2 years (range: 3 months–4 years); the median daily levodopa dosage was 600 mg (range: 50–1,600 mg). Dyskinesia severity led to levodopa adjustments in 5 patients, and all improved. Patients with dyskinesia were diagnosed with parkinsonism at a significantly younger age compared with patients without dyskinesia (p < 0.001). Levodopa dosage was unrelated to increased risk of dyskinesias among DLB and PDD. In contrast, 30.1% of levodopa-treated patients with PD developed dyskinesia. In age-, sex-, and levodopa dosage–adjusted models, Patients with DLB and PDD each had lower odds of developing dyskinesia than patients with PD (odds ratio = 0.42, 95% CI 0.21–0.88; p = 0.02).

Conclusions

The dyskinesia risk for levodopa-treated patients with DLB or PDD was substantially less than for levodopa-treated patients with PD.




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Cerebral venous thrombosis: Associations between disease severity and cardiac markers

Background

Plasma cardiac troponin (cTn) elevation occurs in acute ischemic stroke and intracranial hemorrhage and can suggest a poor prognosis. Because acute cerebral venous thrombosis (CVT) might lead to venous stasis, which could result in cardiac stress, it is important to evaluate whether cTn elevation occurs in patients with CVT.

Methods

Inpatients at Johns Hopkins Hospital from 2005 to 2015 meeting the following criteria were included: CVT (ICD-9 codes with radiologic confirmation) and available admission electrocardiogram (ECG) and cTn level. In regression models, presence of ECG abnormalities and cTn elevation (>0.06 ng/mL) were evaluated as dependent variables in separate models, with location and severity of CVT involvement as independent variables, adjusted for age, sex, and hypertension.

Results

Of 81 patients with CVST, 53 (66%) met the inclusion criteria. Participants were, on average, aged 42 years, white (71%), and female (66%). The left transverse sinus was most commonly thrombosed (47%), with 66% having >2 veins thrombosed. Twenty-two (41%) had cTn elevation. Odds of cTn elevation increased per each additional vein thrombosed (adjusted OR 2.79, 95% CI [1.08–7.23]). Of those with deep venous involvement, 37.5% had cTn elevation compared with 4.4% without deep clots (p = 0.02). Venous infarction (n = 15) was associated with a higher mean cTn (0.14 vs 0.02 ng/mL, p = 0.009) and was predictive of a higher cTn in adjusted models (β = 0.15, 95% CI [0.06–0.25]).

Conclusions

In this single-center cohort study, markers of CVT severity were associated with increased odds of cTn elevation; further investigation is needed to elucidate causality and significance.




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Author response: Symptom burden among individuals with Parkinson disease: A national survey

We appreciate the readers' comments on the prevalence and impact of apathy on quality of life among individuals with Parkinson disease. In constructing our survey instrument, we discussed the inclusion of apathy as a symptom. However, we ultimately opted against inclusion because of concerns about the specificity of terminology in our online survey. Patients and care partners may not be familiar with the term "apathy,"and near-synonyms such as "reduced motivation" have substantial overlap with other nonmotor features. Still, as the readers point out, apathy is extremely common and under-recognized. Similar to many of the nonmotor symptoms identified in our study,1 we agree that clinicians should be screening for apathy among those with Parkinson disease.




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Reader response: Symptom burden among individuals with Parkinson disease: A national survey

We read with great interest the study by Tarolli et al.,1 which explored the burden of disease in Parkinson disease (PD) by evaluating the prevalence of nonmotor symptoms and their association with quality of life. The authors selected nonmotor symptoms based on literature review, expert opinions, and patient interviews. We note that apathy, which has major consequences for patients and carers, was not included as a relevant nonmotor symptom in their study. We performed a subcohort analysis of 60 patients from a study of pain in PD in 110 outpatients (PaCoMo-study, registered trial number: NL6311402917 [toetsingonline.nl]). We retrospectively reviewed the medical records to check whether the clinician identified apathy in these patients in the previous year, which was the case in 15% of the patients (n = 9). Blind to those results, patients were examined with the Apathy Scale (AS).2 In total, 63.3% (n = 38) of the patients scored positive on the AS. Only 18.4% of the patients who scored positive on the AS were also classified or mentioned with apathy in the medical records by clinicians.




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Ahmed A, Fend PI, Gaensbauer JT, Reves RR, Khurana R, Salcedo K, Punnoose R, Katz DJ, for the TUBERCULOSIS EPIDEMIOLOGIC STUDIES CONSORTIUM. Interferon-{gamma} Release Assays in Children <15 Years of Age. Pediatrics. 2020:145(1):e20191930




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Teenager With Abdominal Pain and Decreased Appetite

A 16-year-old girl presented to her primary care physician with a one-month history of decreased appetite and abdominal pain. She had normal bowel movements and no vomiting, but her periumbilical pain limited her ability to finish most meals. She had gradual weight loss over the previous 2 years, and during the previous 4 years, she intermittently received counseling for depression after the loss of her mother. Her initial physical examination and laboratory evaluation were unremarkable. She was referred to a nutritionist, adolescent medicine, and pediatric gastroenterology. Her presentation evolved over time, which ultimately led to a definitive diagnosis.




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Network Implementation of Guideline for Early Detection Decreases Age at Cerebral Palsy Diagnosis

BACKGROUND AND OBJECTIVES:

Early diagnosis of cerebral palsy (CP) is critical in obtaining evidence-based interventions when plasticity is greatest. In 2017, international guidelines for early detection of CP were published on the basis of a systematic review of evidence. Our study aim was to reduce the age at CP diagnosis throughout a network of 5 diverse US high-risk infant follow-up programs through consistent implementation of these guidelines.

METHODS:

The study leveraged plan-do-study-act and Lean methodologies. The primary outcome was age at CP diagnosis. Data were acquired during the corresponding 9-month baseline and quarterly throughout study. Balancing measures were clinic no-show rates and parent perception of the diagnosis visit. Clinic teams conducted strengths, weaknesses, opportunities, and threats analyses, process flow evaluations, standardized assessments training, and parent questionnaires. Performance of a 3- to 4-month clinic visit was a critical process step because it included a Hammersmith Infant Neurologic Examination, a General Movements Assessment, and standardized assessments of motor function.

RESULTS:

The age at CP diagnosis decreased from a weighted average of 19.5 (95% confidence interval 16.2 to 22.8) to 9.5 months (95% confidence interval 4.5 to 14.6), with P = .008; 3- to 4-month visits per site increased from the median (interquartile range) 14 (5.2–73.7) to 54 (34.5–152.0), with P < .001; and no-show rates were not different. Parent questionnaires revealed positive provider perception with improvement opportunities for information content and understandability.

CONCLUSIONS:

Large-scale implementation of international guidelines for early detection of CP is feasible in diverse high-risk infant follow-up clinics. The initiative was received positively by families and without adversely affecting clinic operational flow. Additional parent support and education are necessary.




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Fear and Foxes: An Educational Primer for Use with "Anterior Pituitary Transcriptome Suggests Differences in ACTH Release in Tame and Aggressive Foxes" [Primer]

The way genes contribute to behavior is complicated. Although there are some single genes with large contributions, most behavioral differences are due to small effects from many interacting genes. This makes it hard to identify the genes that cause behavioral differences. Mutagenesis screens in model organisms, selective breeding experiments in animals, comparisons between related populations with different behaviors, and genome-wide association studies in humans are promising and complementary approaches to understanding the heritable aspects of complex behaviors. To connect genes to behaviors requires measuring behavioral differences, locating correlated genetic changes, determining when, where, and how these candidate genes act, and designing causative confirmatory experiments. This area of research has implications from basic discovery science to human mental health.




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Leishmania donovani Subverts Host Immune Response by Epigenetic Reprogramming of Macrophage M(Lipopolysaccharides + IFN-{gamma})/M(IL-10) Polarization [INFECTIOUS DISEASE AND HOST RESPONSE]

Key Points

  • L. donovani induces histone lysine methyltransferases/demethylases in the host.

  • L. donovani–induced epigenetic enzymes induce host M(IL-10) polarization.

  • Knockdown of epigenetic enzymes inhibited parasite multiplication in infected host.




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    T Follicular Helper Cells Regulate Humoral Response for Host Protection against Intestinal Citrobacter rodentium Infection [INFECTIOUS DISEASE AND HOST RESPONSE]

    Key Points

  • Lack of Tfh cells renders the mice susceptible to C. rodentium infection.

  • Tfh cell–dependent protective Abs are essential to control C. rodentium.

  • Tfh cells regulate IgG1 response to C. rodentium infection.




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    Development and Characterization of an Avirulent Leishmania major Strain [INFECTIOUS DISEASE AND HOST RESPONSE]

    Key Points

  • Virulent and avirulent parasites significantly differ in their proteome profiles.

  • Avirulent parasites fail to inhibit CD40 signaling.

  • Avirulent parasite strain is a potential antileishmanial vaccine candidate.




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    Cytomegalovirus Coinfection Is Associated with Increased Vascular-Homing CD57+ CD4 T Cells in HIV Infection [INFECTIOUS DISEASE AND HOST RESPONSE]

    Key Points

  • CMV coinfection promotes the generation of CD57+ CD4 Tmem in PLWH.

  • CD2/LFA-3 costimulation enhances the functionality of CD57+ CD4 Tmem.

  • IL-15 and TNF enhance chemoattraction of CD57+ CD4 Tmem to CX3CL1+ endothelial cells.




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    Complexes between C-Reactive Protein and Very Low Density Lipoprotein Delay Bacterial Clearance in Sepsis [INFECTIOUS DISEASE AND HOST RESPONSE]

    Key Points

  • Kupffer cells phagocytose both bacteria and CRP–VLDL complexes.

  • High levels of CRP–VLDL complexes delay bacterial clearance.

  • Pch disrupts CRP–VLDL complexes to improve bacterial clearance.




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    The Factor H-Binding Site of CspZ as a Protective Target against Multistrain, Tick-Transmitted Lyme Disease [Microbial Immunity and Vaccines]

    The spirochete Borrelia burgdorferi sensu lato is the causative agent of Lyme disease (LD). The spirochetes produce the CspZ protein that binds to a complement regulator, factor H (FH). Such binding downregulates activation of host complement to facilitate spirochete evasion of complement killing. However, vaccination with CspZ does not protect against LD infection. In this study, we demonstrated that immunization with CspZ-YA, a CspZ mutant protein with no FH-binding activity, protected mice from infection by several spirochete genotypes introduced via tick feeding. We found that the sera from CspZ-YA-vaccinated mice more efficiently eliminated spirochetes and blocked CspZ FH-binding activity than sera from CspZ-immunized mice. We also found that vaccination with CspZ, but not CspZ-YA, triggered the production of anti-FH antibodies, justifying CspZ-YA as an LD vaccine candidate. The mechanistic and efficacy information derived from this study provides insights into the development of a CspZ-based LD vaccine.




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    Crystal Structure of African Swine Fever Virus pS273R Protease and Implications for Inhibitor Design [Structure and Assembly]

    African swine fever (ASF) is a highly contagious hemorrhagic viral disease of domestic and wild pigs that is responsible for serious economic and production losses. It is caused by the African swine fever virus (ASFV), a large and complex icosahedral DNA virus of the Asfarviridae family. Currently, there is no effective treatment or approved vaccine against the ASFV. pS273R, a specific SUMO-1 cysteine protease, catalyzes the maturation of the pp220 and pp62 polyprotein precursors into core-shell proteins. Here, we present the crystal structure of the ASFV pS273R protease at a resolution of 2.3 Å. The overall structure of the pS273R protease is represented by two domains named the "core domain" and the N-terminal "arm domain." The "arm domain" contains the residues from M1 to N83, and the "core domain" contains the residues from N84 to A273. A structure analysis reveals that the "core domain" shares a high degree of structural similarity with chlamydial deubiquitinating enzyme, sentrin-specific protease, and adenovirus protease, while the "arm domain" is unique to ASFV. Further, experiments indicated that the "arm domain" plays an important role in maintaining the enzyme activity of ASFV pS273R. Moreover, based on the structural information of pS273R, we designed and synthesized several peptidomimetic aldehyde compounds at a submolar 50% inhibitory concentration, which paves the way for the design of inhibitors to target this severe pathogen.

    IMPORTANCE African swine fever virus, a large and complex icosahedral DNA virus, causes a deadly infection in domestic pigs. In addition to Africa and Europe, countries in Asia, including China, Vietnam, and Mongolia, were negatively affected by the hazards posed by ASFV outbreaks in 2018 and 2019, at which time more than 30 million pigs were culled. Until now, there has been no vaccine for protection against ASFV infection or effective treatments to cure ASF. Here, we solved the high-resolution crystal structure of the ASFV pS273R protease. The pS273R protease has a two-domain structure that distinguishes it from other members of the SUMO protease family, while the unique "arm domain" has been proven to be essential for its hydrolytic activity. Moreover, the peptidomimetic aldehyde compounds designed to target the substrate binding pocket exert prominent inhibitory effects and can thus be used in a potential lead for anti-ASFV drug development.




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    Heterogeneous Nuclear Ribonucleoprotein L Negatively Regulates Foot-and-Mouth Disease Virus Replication through Inhibition of Viral RNA Synthesis by Interacting with the Internal Ribosome Entry Site in the 5' Untranslated Region [Virus-Cell Interactio

    Upon infection, the highly structured 5' untranslated region (5' UTR) of picornavirus is involved in viral protein translation and RNA synthesis. As a critical element in the 5' UTR, the internal ribosome entry site (IRES) binds to various cellular proteins to function in the processes of picornavirus replication. Foot-and-mouth disease virus (FMDV) is an important member in the family Picornaviridae, and its 5' UTR contains a functional IRES element. In this study, the cellular heterogeneous nuclear ribonucleoprotein L (hnRNP L) was identified as an IRES-binding protein for FMDV by biotinylated RNA pulldown assays, mass spectrometry (MS) analysis, and determination of hnRNP L-IRES interaction regions. Further, we found that hnRNP L inhibited the growth of FMDV through binding to the viral IRES and that the inhibitory effect of hnRNP L on FMDV growth was not due to FMDV IRES-mediated translation, but to influence on viral RNA synthesis. Finally, hnRNP L was demonstrated to coimmunoprecipitate with RNA-dependent RNA polymerase (3Dpol) in an FMDV RNA-dependent manner in the infected cells. Thus, our results suggest that hnRNP L, as a critical IRES-binding protein, negatively regulates FMDV replication by inhibiting viral RNA synthesis, possibly by remaining in the replication complex.

    IMPORTANCE Picornaviruses, as a large family of human and animal pathogens, cause a bewildering array of disease syndromes. Many host factors are implicated in the pathogenesis of these viruses, and some proteins interact with the viral IRES elements to affect function. Here, we report for the first time that cellular hnRNP L specifically interacts with the IRES of the picornavirus FMDV and negatively regulates FMDV replication through inhibiting viral RNA synthesis. Further, our results showed that hnRNP L coimmunoprecipitates with FMDV 3Dpol in a viral RNA-dependent manner, suggesting that it may remain in the replication complex to function. The data presented here would facilitate further understanding of virus-host interactions and the pathogenesis of picornavirus infections.




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    NF-{kappa}B and Keap1 Interaction Represses Nrf2-Mediated Antioxidant Response in Rabbit Hemorrhagic Disease Virus Infection [Pathogenesis and Immunity]

    The rabbit hemorrhagic disease virus (RHDV), which belongs to the family Caliciviridae and the genus Lagovirus, causes lethal fulminant hepatitis in rabbits. RHDV decreases the activity of antioxidant enzymes regulated by Nrf2 in the liver. Antioxidants are important for the maintenance of cellular integrity and cytoprotection. However, the mechanism underlying the regulation of the Nrf2-antioxidant response element (ARE) signaling pathway by RHDV remains unclear. Using isobaric tags for relative and absolute quantification (iTRAQ) technology, the current study demonstrated that RHDV inhibits the induction of ARE-regulated genes and increases the expression of the p50 subunit of the NF-B transcription factor. We showed that RHDV replication causes a remarkable increase in reactive oxygen species (ROS), which is simultaneously accompanied by a significant decrease in Nrf2. It was found that nuclear translocation of Keap1 plays a key role in the nuclear export of Nrf2, leading to the inhibition of Nrf2 transcriptional activity. The p50 protein partners with Keap1 to form the Keap1-p50/p65 complex, which is involved in the nuclear translocation of Keap1. Moreover, upregulation of Nrf2 protein levels in liver cell nuclei by tert-butylhydroquinone (tBHQ) delayed rabbit deaths due to RHDV infection. Considered together, our findings suggest that RHDV inhibits the Nrf2-dependent antioxidant response via nuclear translocation of Keap1-NF-B complex and nuclear export of Nrf2 and provide new insight into the importance of oxidative stress during RHDV infection.

    IMPORTANCE Recent studies have reported that rabbit hemorrhagic disease virus (RHDV) infection reduced Nrf2-related antioxidant function. However, the regulatory mechanisms underlying this process remain unclear. The current study showed that the NF-B p50 subunit partners with Keap1 to form the Keap1-NF-B complex, which plays a key role in the inhibition of Nrf2 transcriptional activity. More importantly, upregulated Nrf2 activity delayed the death of RHDV-infected rabbits, strongly indicating the importance of oxidative damage during RHDV infection. These findings may provide novel insights into the pathogenesis of RHDV.




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    Asking young children to &#x201C;do science&#x201D; instead of &#x201C;be scientists&#x201D; increases science engagement in a randomized field experiment [Psychological and Cognitive Sciences]

    Subtle features of common language can imply to young children that scientists are a special and distinct kind of person—a way of thinking that can interfere with the development of children’s own engagement with science. We conducted a large field experiment (involving 45 prekindergarten schools, 130 teachers, and over 1,100...




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    Starvation and antimetabolic therapy promote cytokine release and recruitment of immune cells [Immunology and Inflammation]

    Cellular starvation is typically a consequence of tissue injury that disrupts the local blood supply but can also occur where cell populations outgrow the local vasculature, as observed in solid tumors. Cells react to nutrient deprivation by adapting their metabolism, or, if starvation is prolonged, it can result in cell...




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    Inhaled Corticosteroid Treatment in Chronic Obstructive Pulmonary Disease (COPD): Boon or Bane?

    Inhaled corticosteroid (ICS)–based therapy is often used for patients with chronic obstructive pulmonary disease (COPD). However, this approach is under scrutiny because of ICS overuse in patients for whom it is not recommended and because of concerns about adverse events, particularly pneumonia, with long-term ICS use. Evidence suggests ICS may be beneficial in specific patients, namely, those with high blood eosinophil counts (eg, ≥300 cells/µL) or who are at a high risk of exacerbations. According to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2020 ABCD assessment tool, these patients belong in group D. For these patients, recommended initial treatment includes ICS in combination with long-acting β2-agonists (LABAs) when blood eosinophil counts are ≥300 cells/µL or LABA + long-acting muscarinic antagonist (LAMA) when patients are highly symptomatic, that is, with greater dyspnea and/or exercise limitation. Follow-up treatments for patients with persistent dyspnea and/or exacerbations may include LABA + ICS, LABA + LAMA, or LABA + LAMA + ICS, with use of ICS being guided by blood eosinophil counts. In this review, differences in the inflammatory mechanism underlying COPD and asthma and the role of ICS treatment in COPD are summarized. Furthermore, findings from recent clinical trials where use of ICS-based dual or triple therapy in COPD was compared with LABA + LAMA therapy and trials in which ICS withdrawal was evaluated in patients with COPD are reviewed. Finally, a step-by-step guide for ICS withdrawal in patients who are unlikely to benefit from this treatment is proposed. A video of the author discussing the overall takeaway of the review article could be downloaded from the link provided: https://www.youtube.com/watch?v=Uq7Sr5jqPDI.




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    Eliminating Patient Identified Barriers to Decrease Medicaid Inpatient Admission Rates and Improve Quality of Care

    Background and Objectives:

    The goal of this study was to decrease admission and readmission rate for the 2296 Medicaid patients in our clinic. Our focus was to eliminate patient identified barriers to care that led to decreased quality of care. The identified barriers for our clinic included distance to care, poor same-day access, communication, and fragmented care. A team-based, collaborative approach using members from all aspects of patient care.

    Methods:

    An initial survey identified which barriers to care our patients felt obstructed their care. With this data, along with a national literature review, our team used biweekly quality team meetings with LEAN methodology and Plan-Do-Study-Act cycles to create a 4-phase quality improvement project. A home-visit program to decrease distance to care, walk-in clinic to improve same-day access, strengthened collaboration with outside care managers and clinic staff to improve communication, and the introduction of an in-house phlebotomist to improve fragmented care were created and studied between June 2015 and December 2018. Admission rate, avoidable readmission rate, as well as other quality of care measurements were assessed with electronic medical record reports and through North Carolina Medicaid data reports.

    Results:

    Overall Medicaid admissions decreased 32.7% from starting numbers, 40.2% below expected benchmarks. Avoidable readmissions decreased 41.8%, 53.8% below the expected benchmark. Improvements in same-day access numbers and lab completion rate were also seen.

    Discussion:

    The team-based approach to eliminating patient-identified barriers decreased both admissions and avoidable readmissions for our Medicaid patients. It also improved quality-of-care measures. This approach has been shown to be beneficial at our clinic and can easily be replicated in other settings.




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    Food restriction delays seasonal sexual maturation but does not increase torpor use in male bats [RESEARCH ARTICLE]

    Ewa Komar, Dina K. N. Dechmann, Nicolas J. Fasel, Marcin Zegarek, and Ireneusz Ruczynski

    Balancing energy budgets can be challenging, especially in periods of food shortage, adverse weather conditions and increased energy demand due to reproduction. Bats have particularly high energy demands compared to other mammals and regularly use torpor to save energy. However, while torpor limits energy expenditure, it can also downregulate important processes, such as sperm production. This constraint could result in a trade-off between energy saving and future reproductive capacity. We mimicked harsh conditions by restricting food and tested the effect on changes in body mass, torpor use and seasonal sexual maturation in male parti-coloured bats (Vespertilio murinus). Food-restricted individuals managed to maintain their initial body mass, while in well-fed males, mass increased. Interestingly, despite large differences in food availability, there were only small differences in torpor patterns. However, well-fed males reached sexual maturity up to half a month earlier. Our results thus reveal a complex trade-off in resource allocation; independent of resource availability, males maintain a similar thermoregulation strategy and favour fast sexual maturation, but limited resources and low body mass moderate this latter process.




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    Human recreation decreases antibody titre in bird nestlings: an overlooked transgenerational effect of disturbance [RESEARCH ARTICLE]

    Yves Bötsch, Zulima Tablado, Bettina Almasi, and Lukas Jenni

    Outdoor recreational activities are booming and most animals perceive humans as predators, which triggers behavioural and/or physiological reactions [e.g. heart rate increase, activation of the hypothalamic–pituitary–adrenal (HPA) axis]. Physiological stress reactions have been shown to affect the immune system of an animal and therefore may also affect the amount of maternal antibodies a female transmits to her offspring. A few studies have revealed that the presence of predators affects the amount of maternal antibodies deposited into eggs of birds. In this study, using Eurasian blue and great tit offspring (Cyanistes caeruleus and Parus major) as model species, we experimentally tested whether human recreation induces changes in the amount of circulating antibodies in young nestlings and whether this effect is modulated by habitat and competition. Moreover, we investigated whether these variations in antibody titre in turn have an impact on hatching success and offspring growth. Nestlings of great tit females that had been disturbed by experimental human recreation during egg laying had lower antibody titres compared with control nestlings. Antibody titre of nestling blue tits showed a negative correlation with the presence of great tits, rather than with human disturbance. The hatching success was positively correlated with the average amount of antibodies in great tit nestlings, independent of the treatment. Antibody titre in the first days of life in both species was positively correlated with body mass, but this relationship disappeared at fledging and was independent of treatment. We suggest that human recreation may have caused a stress-driven activation of the HPA axis in breeding females, chronically increasing their circulating corticosterone, which is known to have an immunosuppressive function. Either, lower amounts of antibodies are transmitted to nestlings or impaired transfer mechanisms lead to lower amounts of immunoglobulins in the eggs. Human disturbance could, therefore, have negative effects on nestling survival at early life-stages, when nestlings are heavily reliant on maternal antibodies, and in turn lead to lower breeding success and parental fitness. This is a so far overlooked effect of disturbance on early life in birds.




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    Wolbachia-infected ant colonies have increased reproductive investment and an accelerated life cycle [RESEARCH ARTICLE]

    Rohini Singh and Timothy A. Linksvayer

    Wolbachia is a widespread group of maternally-transmitted endosymbiotic bacteria that often manipulates the reproductive strategy and life history of its hosts to favor its own transmission. Wolbachia mediated phenotypic effects are well characterized in solitary hosts, but effects in social hosts are unclear. The invasive pharaoh ant, Monomorium pharaonis, shows natural variation in Wolbachia infection between colonies and can be readily bred under laboratory conditions. We previously showed that Wolbachia-infected pharaoh ant colonies had more queen-biased sex ratios than uninfected colonies, which is expected to favor the spread of maternally-transmitted Wolbachia. Here, we further characterize the effects of Wolbachia on the short- and longer-term reproductive and life history traits of pharaoh ant colonies. First, we characterized the reproductive differences between naturally infected and uninfected colonies at three discrete time points and found that infected colonies had higher reproductive investment (i.e. infected colonies produced more new queens), particularly when existing colony queens were three months old. Next, we compared the long-term growth and reproduction dynamics of infected and uninfected colonies across their whole life cycle. Infected colonies had increased colony-level growth and early colony reproduction, resulting in a shorter colony life cycle, when compared to uninfected colonies.




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    Whale sharks increase swimming effort while filter feeding, but appear to maintain high foraging efficiencies [RESEARCH ARTICLE]

    David E. Cade, J. Jacob Levenson, Robert Cooper, Rafael de la Parra, D. Harry Webb, and Alistair D. M. Dove

    Whale sharks (Rhincodon typus Smith 1828) – the largest extant fish species – reside in tropical environments, making them an exception to the general rule that animal size increases with latitude. How this largest fish thrives in tropical environments that promote high metabolism but support less robust zooplankton communities has not been sufficiently explained. We used open-source inertial measurement units (IMU) to log 397 hours of whale shark behavior in Yucatan, Mexico, at a site of both active feeding and intense wildlife tourism. Here we show that the strategies employed by whale sharks to compensate for the increased drag of an open mouth are similar to ram-feeders five orders of magnitude smaller and one order of magnitude larger. Presumed feeding constituted 20% of the total time budget of four sharks, with individual feeding bouts lasting up to 11 consecutive hrs. Compared to normal, sub-surface swimming, three sharks increased their stroke rate and amplitude while surface feeding, while one shark that fed at depth did not demonstrate a greatly increased energetic cost. Additionally, based on time-depth budgets, we estimate that aerial surveys of shark populations should consider including a correction factor of 3 to account for the proportion of daylight hours that sharks are not visible at the surface. With foraging bouts generally lasting several hours, interruptions to foraging during critical feeding periods may represent substantial energetic costs to these endangered species, and this study presents baseline data from which management decisions affecting tourist interactions with whale sharks may be made.




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    Tubular STAT3 Limits Renal Inflammation in Autosomal Dominant Polycystic Kidney Disease

    Background

    The inactivation of the ciliary proteins polycystin 1 or polycystin 2 leads to autosomal dominant polycystic kidney disease (ADPKD). Although signaling by primary cilia and interstitial inflammation both play a critical role in the disease, the reciprocal interactions between immune and tubular cells are not well characterized. The transcription factor STAT3, a component of the cilia proteome that is involved in crosstalk between immune and nonimmune cells in various tissues, has been suggested as a factor fueling ADPKD progression.

    Method

    To explore how STAT3 intersects with cilia signaling, renal inflammation, and cyst growth, we used conditional murine models involving postdevelopmental ablation of Pkd1, Stat3, and cilia, as well as cultures of cilia-deficient or STAT3-deficient tubular cell lines.

    Results

    Our findings indicate that, although primary cilia directly modulate STAT3 activation in vitro, the bulk of STAT3 activation in polycystic kidneys occurs through an indirect mechanism in which primary cilia trigger macrophage recruitment to the kidney, which in turn promotes Stat3 activation. Surprisingly, although inactivating Stat3 in Pkd1-deficient tubules slightly reduced cyst burden, it resulted in a massive infiltration of the cystic kidneys by macrophages and T cells, precluding any improvement of kidney function. We also found that Stat3 inactivation led to increased expression of the inflammatory chemokines CCL5 and CXCL10 in polycystic kidneys and cultured tubular cells.

    Conclusions

    STAT3 appears to repress the expression of proinflammatory cytokines and restrict immune cell infiltration in ADPKD. Our findings suggest that STAT3 is not a critical driver of cyst growth in ADPKD but rather plays a major role in the crosstalk between immune and tubular cells that shapes disease expression.