Now showing items 1-20 of 11416

    • Asymptomatic Bacterial Vaginosis Is Associated With Depletion of Mature Superficial Cells Shed From the Vaginal Epithelium

      O'Hanlon, D.E.; Gajer, P.; Brotman, R.M.; Ravel, J. (Frontiers Media S.A., 2020)
      Previous studies have described bacterial vaginosis (BV) as associated with increased cell-shedding from the cervicovaginal epithelium. Cell-shedding in excess of cell-proliferation is thought to decrease epithelial barrier function and increase susceptibility to infection. This study evaluated the number of shed cells in mid-vaginal smears from women with a diagnosis of symptomatic BV (sBV, n = 17), asymptomatic BV (aBV, n = 71), or no BV (n = 104) by Amsel criteria. The sBV smears contained significantly more shed cells (median 158/100X field) than no BV smears (median 91/100X field), p = 7.2e-9. However, we observed that aBV smears contained significantly fewer shed cells (median 35/100X field) than no BV smears, p = 22.0e-16. The sizes of cell-aggregates (cells shed in sometimes multilayered sections with intact cell-cell attachments) followed the same pattern. Cell-aggregates in sBV smears were significantly larger (median ~220,000 ?m2) than those in no BV smears (median ~50,000 ?m2), p = 1.8e-6, but cell-aggregates in aBV smears were significantly smaller (median ~7,000 ?m2) than those in no BV smears, p = 0.0028. We also compared the superficial cell index (SCI), a measure of cervicovaginal epithelial cell maturity, in no BV and aBV smears with relatively low numbers of shed cells (?50/100X field). The SCI of no BV smears was significantly higher (median 0.86) than that of aBV smears (median 0.35), p = 4.3e-98, suggesting a depletion of mature cells with exposure and shedding of underlying immature cells in aBV with low number of shed cells. These results indicate that aBV may contribute disproportionately to the increased susceptibility to reproductive tract infections associated with BV. Our findings remained true when considering only those smears in which the microbiota comprised a diverse set of strict and facultative anaerobic bacteria [Community State Type IV (n = 162)], thus excluding those dominated by Lactobacillus spp. This is consistent with our developing hypothesis that high-shedding sBV and low-shedding aBV could be temporally separated phases of the same condition, rather than two separate forms of BV. These findings might inform future work on clinical management of symptomatic and asymptomatic bacterial vaginosis. Copyright The Authors.
    • ENIGMA and global neuroscience: A decade of large-scale studies of the brain in health and disease across more than 40 countries

      Adhikari, B.M.; Kochunov, P.; ENIGMA Consortium (Springer Nature, 2020)
      This review summarizes the last decade of work by the ENIGMA (Enhancing NeuroImaging Genetics through Meta Analysis) Consortium, a global alliance of over 1400 scientists across 43 countries, studying the human brain in health and disease. Building on large-scale genetic studies that discovered the first robustly replicated genetic loci associated with brain metrics, ENIGMA has diversified into over 50 working groups (WGs), pooling worldwide data and expertise to answer fundamental questions in neuroscience, psychiatry, neurology, and genetics. Most ENIGMA WGs focus on specific psychiatric and neurological conditions, other WGs study normal variation due to sex and gender differences, or development and aging; still other WGs develop methodological pipelines and tools to facilitate harmonized analyses of "big data" (i.e., genetic and epigenetic data, multimodal MRI, and electroencephalography data). These international efforts have yielded the largest neuroimaging studies to date in schizophrenia, bipolar disorder, major depressive disorder, post-traumatic stress disorder, substance use disorders, obsessive-compulsive disorder, attention-deficit/hyperactivity disorder, autism spectrum disorders, epilepsy, and 22q11.2 deletion syndrome. More recent ENIGMA WGs have formed to study anxiety disorders, suicidal thoughts and behavior, sleep and insomnia, eating disorders, irritability, brain injury, antisocial personality and conduct disorder, and dissociative identity disorder. Here, we summarize the first decade of ENIGMA's activities and ongoing projects, and describe the successes and challenges encountered along the way. We highlight the advantages of collaborative large-scale coordinated data analyses for testing reproducibility and robustness of findings, offering the opportunity to identify brain systems involved in clinical syndromes across diverse samples and associated genetic, environmental, demographic, cognitive, and psychosocial factors.
    • Weighty choices: Selecting optimal G-CSF doses for stem cell mobilization to optimize yield

      Farhadfar, N.; Hsu, J.W.; Yared, J.A. (American Society of Hematology, 2020)
      There are limited data on the effect of donor body mass index (BMI) on peripheral blood stem cell (PBSC) mobilization response to granulocyte colony-stimulating factor (G-CSF), especially in unrelated donors. Obesity has been associated with persistent leukocytosis, elevated circulating progenitor cells, and enhanced stem cell mobilization. Therefore, we hypothesized that adequate collection of CD341 cells may be achieved with lower doses (per kilogram of body weight) of G-CSF in donors with higher BMI compared with donors with lower BMI. Using the Center for International Blood and Marrow Transplant Research database, we evaluated the impact of donor BMI on G-CSF-mobilized PBSC yield in healthy unrelated donors. We examined 20 884 PBSC donations collected at National Marrow Donor Program centers between 2006 and 2016. We found significantly higher collection yields in obese and severely obese donors compared with normal and overweight donors. An increase in average daily G-CSF dose was associated with an increase in stem cell yield in donors with normal or overweight BMI. In contrast, an increase in average daily G-CSF dose beyond 780 mg per day in obese and 900 mg per day in severely obese donors did not increase cell yield. Pain and toxicities were assessed at baseline, during G-CSF administration, and postcollection. Obesity was associated with higher levels of self-reported donation-related pain and toxicities in the pericollection and early postdonation recovery periods. This study suggests a maximum effective G-CSF dose for PBSC mobilization in obese and severely obese donors, beyond which higher doses of G-CSF add no increased yield.
    • Randomised trial of azithromycin to eradicate Ureaplasma in preterm infants

      Viscardi, R.M.; Terrin, M.L.; Magder, L.S.; Davis, N.L.; Dulkerian, S.J.; Hassan, H.E.; Eddington, N.D. (BMJ Publishing Group, 2020)
      Objective: To test whether azithromycin eradicates Ureaplasma from the respiratory tract in preterm infants. Design: Prospective, phase IIb randomised, double-blind, placebo-controlled trial. Setting: Seven level III-IV US, academic, neonatal intensive care units (NICUs). Patients: Infants 240-286 weeks' gestation (stratified 240-266; 270-286 weeks) randomly assigned within 4 days following birth from July 2013 to August 2016. Interventions: Intravenous azithromycin 20 mg/kg or an equal volume of D5W (placebo) every 24 hours for 3 days. Main outcome measures: The primary efficacy outcome was Ureaplasma-free survival. Secondary outcomes were all-cause mortality, Ureaplasma clearance, physiological bronchopulmonary dysplasia (BPD) at 36 weeks' postmenstrual age, comorbidities of prematurity and duration of respiratory support. Results: One hundred and twenty-one randomised participants (azithromycin: n=60; placebo: n=61) were included in the intent-to-treat analysis (mean gestational age 26.2±1.4 weeks). Forty-four of 121 participants (36%) were Ureaplasma positive (azithromycin: n=19; placebo: n=25). Ureaplasma-free survival was 55/60 (92% (95% CI 82% to 97%)) for azithromycin compared with 37/61 (61% (95% CI 48% to 73%)) for placebo. Mortality was similar comparing the two treatment groups (5/60 (8%) vs 6/61 (10%)). Azithromycin effectively eradicated Ureaplasma in all azithromycin-assigned colonised infants, but 21/25 (84%) Ureaplasma-colonised participants receiving placebo were culture positive at one or more follow-up timepoints. Most of the neonatal mortality and morbidity was concentrated in 21 infants with lower respiratory tract Ureaplasma colonisation. In a subgroup analysis, physiological BPD-free survival was 5/10 (50%) (95% CI 19% to 81%) among azithromycin-assigned infants with lower respiratory tract Ureaplasma colonisation versus 2/11 (18%) (95% CI 2% to 52%) in placebo-treated infants. Conclusion: A 3-day azithromycin regimen effectively eradicated respiratory tract Ureaplasma colonisation in this study. Copyright Author(s) 2020.
    • Systematic review of statistical methods for safety data in malaria chemoprevention in pregnancy trials

      Patson, N.; Mukaka, M.; Laufer, M.K. (BioMed Central Ltd., 2020)
      Background: Drug safety assessments in clinical trials present unique analytical challenges. Some of these include adjusting for individual follow-up time, repeated measurements of multiple outcomes and missing data among others. Furthermore, pre-specifying appropriate analysis becomes difficult as some safety endpoints are unexpected. Although existing guidelines such as CONSORT encourage thorough reporting of adverse events (AEs) in clinical trials, they provide limited details for safety data analysis. The limited guidelines may influence suboptimal analysis by failing to account for some analysis challenges above. A typical example where such challenges exist are trials of anti-malarial drugs for malaria prevention during pregnancy. Lack of proper standardized evaluation of the safety of antimalarial drugs has limited the ability to draw conclusions about safety. Therefore, a systematic review was conducted to establish the current practice in statistical analysis for preventive antimalarial drug safety in pregnancy. Methods: The search included five databases (PubMed, Embase, Scopus, Malaria in Pregnancy Library and Cochrane Central Register of Controlled Trials) to identify original English articles reporting Phase III randomized controlled trials (RCTs) on anti-malarial drugs for malaria prevention in pregnancy published from January 2010 to July 2019. Results: Eighteen trials were included in this review that collected multiple longitudinal safety outcomes including AEs. Statistical analysis and reporting of the safety outcomes in all the trials used descriptive statistics; proportions/counts (n = 18, 100%) and mean/median (n = 2, 11.1%). Results presentation included tabular (n = 16, 88.9%) and text description (n = 2, 11.1%). Univariate inferential methods were reported in most trials (n = 16, 88.9%); including Chi square/Fisher's exact test (n = 12, 66.7%), t test (n = 2, 11.1%) and Mann-Whitney/Wilcoxon test (n = 1, 5.6%). Multivariable methods, including Poisson and negative binomial were reported in few trials (n = 3, 16.7%). Assessment of a potential link between missing efficacy data and safety outcomes was not reported in any of the trials that reported efficacy missing data (n = 7, 38.9%). Conclusion: The review demonstrated that statistical analysis of safety data in anti-malarial drugs for malarial chemoprevention in pregnancy RCTs is inadequate. The analyses insufficiently account for multiple safety outcomes potential dependence, follow-up time and informative missing data which can compromise anti-malarial drug safety evidence development, based on the available data. Copyright 2020 The Author(s).
    • Validity of EQ-5D utility index and minimal clinically important difference estimation among patients with chronic obstructive pulmonary disease

      Bae, E.; Choi, S.-E.; Lee, H. (BioMed Central Ltd., 2020)
      Background: The discriminatory ability of multi-attribute utility (MAU) measures compared to condition-specific measures (CSM) in assessing health-related quality of life (HRQoL) among patients with chronic obstructive pulmonary disease (COPD) is an unsettled issue. This study investigated the quality of life of patients with COPD with three different HRQoL instruments and examined whether they could differentiate between adjacent severity groups in a statistically and clinically meaningful manner. In the process, the minimal clinically important differences (MCID) of the EQ-5D utility index were estimated. Methods: Cross-sectional survey data were collected from patients with mild to very severe COPD in South Korea. In addition to demographic and clinical information, the following HRQoL questionnaires were used: The three-level five-dimensional Euro-Quality of Life tool (EQ-5D-3L), the EQ-Visual Analog Scale (EQ-VAS), and the Chronic Obstructive Pulmonary Disease Assessment Test (CAT). Patients' health-related quality of life was analyzed with reference to severity groups based on the Global Initiative for Chronic Obstructive Lung Disease (GOLD) classification. To investigate the discriminatory ability of the HRQoL instruments between COPD severity groups, tests examining variance, covariance, and standardized mean difference were performed. After estimating the MCID of the EQ-5D utility index using the anchor-based method, we investigated whether the differences in the EQ-5D utility scores between groups exceeded the clinically meaningful minimum level. Results: A total of 298 patients completed this study. All the quality of life scores showed statistically significant differences between the GOLD severity groups. The pooled MCID estimate for the EQ-5D utility index was 0.028 (range: 0.017-0.033). Even after adjusting for other factors affecting quality of life, the EQ-5D utility index differentiated the GOLD groups well. Conclusions: We conclude that the EQ-5D utility index is a valid instrument for measuring the quality of life of patients with COPD, and the pooled MCID estimate for the EQ-5D utility index was 0.028. Copyright 2020 The Author(s).
    • Successful Moderation in Online Patient Communities: Inductive Case Study

      Skousen, T.; Safadi, H.; Safadi, S. (JMIR Publications, 2020)
      BACKGROUND: Online patient communities are becoming more prevalent as a resource to help patients take control of their health. However, online patient communities experience challenges that require active moderation. OBJECTIVE: This study aimed to identify the challenges of sustaining a thriving online patient community and the moderation practices employed to address the challenges and manage the online patient community successfully. METHODS: An inductive case study of Mayo Clinic Connect was analyzed using the grounded theory methodology. Insights for the analysis were obtained from semistructured interviews with community managers and community members. Secondary data sources, such as community management documents, observational meeting notes, and community postings, were used to validate and triangulate the findings. RESULTS: We identified four challenges unique to online patient communities. These challenges include passion, nonmedical advice, personal information, and community participation. We identified five categories of practices that community members used to address these challenges and moderate the community successfully. These practices include instructive, semantic, connective, administrative, and policing practices. CONCLUSIONS: Successful moderation in online patient communities requires a multitude of practices to manage the challenges that arise in these communities. Some practices are implemented as preventive measures while other practices are more interventive. Additionally, practices can come from both authority figures and exemplary members. Copyright The Authors.
    • Reproductive tract extracellular vesicles are sufficient to transmit intergenerational stress and program neurodevelopment

      Morgan, C.P.; Shetty, A.; Cisse, Y.M.; Nugent, B.M.; Morrison, K.E.; Huang, W.; Kanyuch, N.; Ament, S.; Kane, M.; Bale, T.L.; et al. (Springer Nature, 2020)
      Extracellular vesicles (EVs) are a unique mode of intercellular communication capable of incredible specificity in transmitting signals involved in cellular function, including germ cell maturation. Spermatogenesis occurs in the testes, behind a protective barrier to ensure safeguarding of germline DNA from environmental insults. Following DNA compaction, further sperm maturation occurs in the epididymis. Here, we report reproductive tract EVs transmit information regarding stress in the paternal environment to sperm, potentially altering fetal development. Using intracytoplasmic sperm injection, we found that sperm incubated with EVs collected from stress-treated epididymal epithelial cells produced offspring with altered neurodevelopment and adult stress reactivity. Proteomic and transcriptomic assessment of these EVs showed dramatic changes in protein and miRNA content long after stress treatment had ended, supporting a lasting programmatic change in response to chronic stress. Thus, EVs as a normal process in sperm maturation, can also perform roles in intergenerational transmission of paternal environmental experience.
    • Associations of Peripheral Artery Disease With Calf Skeletal Muscle Mitochondrial DNA Heteroplasmy

      Gonzalez-Freire, M.; Moore, A.Z.; Guralnik, J.M. (Wiley-Blackwell, 2020)
      Background Patients with peripheral artery disease (PAD) undergo frequent episodes of ischemia-reperfusion in lower extremity muscles that may negatively affect mitochondrial health and are associated with impaired mobility. We hypothesized that skeletal muscle from PAD patients will show high mitochondrial DNA heteroplasmy, especially in regions more susceptible to oxidative damage, such as the displacement loop, and that the degree of heteroplasmy will be correlated with the severity of ischemia and mobility impairment. Methods and Results Mitochondrial mutations and deletions and their relative abundance were identified by targeted mitochondrial DNA sequencing in biopsy specimens of gastrocnemius muscle from 33 PAD (ankle brachial index <0.9) and 9 non-PAD (ankle brachial index >0.9) subjects aged ?60�years. The probability of heteroplasmy per DNA base was significantly higher for PAD subjects than non-PAD within each region. In adjusted models, PAD was associated with higher heteroplasmy than non-PAD (P=0.003), but the association was limited to microheteroplasmy, that is heteroplasmy found in 1% to 5% of all mitochondrial genomes (P=0.004). Heteroplasmy in the displacement loop and coding regions were significantly higher for PAD than non-PAD subjects after adjustment for age, sex, race, and diabetes mellitus (P=0.037 and 0.004, respectively). Low mitochondrial damage, defined by both low mitochondrial DNA copy number and low microheteroplasmy, was associated with better walking performance. Conclusions People with PAD have higher "low frequency" heteroplasmy in gastrocnemius muscle compared with people without PAD. Among people with PAD, those who had evidence of least mitochondrial damage, had better walking performance than those with more mitochondrial damage. Registration URL: Unique identifier: NCT02246660.
    • UMB Covid-19 Coping Kit: Launch Your Life can help get you through this crisis

      University of Maryland, Baltimore. Human Resource Services (2020-04)
    • Biochemical and immunological characterization of an ETEC CFA/I adhesin cholera toxin B subunit chimera

      Jobling, M.G.; Poole, S.T.; Balakrishnan, A. (Public Library of Science, 2020)
      Surface-expressed colonization factors and their subunits are promising candidates for inclusion into a multivalent vaccine targeting enterotoxigenic Escherichia coli (ETEC), a leading cause of acute bacterial diarrhea in developing regions. However, soluble antigens are often poorly immunogenic in the absence of an adjuvant. We show here that the serum immune response to CfaE, the adhesin of the ETEC colonization factor CFA/I, can be enhanced in BALB/c mice by immunization with a chimeric antigen containing CfaE and pentameric cholera toxin B subunit (CTB) of cholera toxin from Vibrio cholerae. We constructed this antigen by replacing the coding sequence for the A1 domain of the cholera toxin A subunit (CTA) with the sequence of donor strand complemented CfaE (dscCfaE) within the cholera toxin operon, resulting in a dscCfaE-CTA2 fusion. After expression, via non-covalent interactions between CTA2 and CTB, the fusion and CTB polypeptides assemble into a complex containing a single dscCfaE-CTA2 protein bound to pentameric CTB (dscCfaE-CTA2/CTB). This holotoxin-like chimera retained the GM1 ganglioside binding activity of CTB, as well as the ability of CfaE to mediate the agglutination of bovine red blood cells when adsorbed to polystyrene beads. When administered intranasally to mice, the presence of CTB in the chimera significantly increased the serum immune response to CfaE compared to dscCfaE alone, stimulating a response similar to that obtained with a matched admixture of dscCfaE and CTB. However, by the orogastric route, immunization with the chimera elicited a superior functional immune response compared to an equivalent admixture of dscCfaE and CTB, supporting further investigation of the chimera as an ETEC vaccine candidate.
    • Real-world evidence to support regulatory decision-making for medicines: Considerations for external control arms

      Burcu, M.; Dreyer, N.A.; Perfetto, E.M. (John Wiley and Sons Ltd, 2020)
      Randomized clinical trials (RCTs) are the gold standard in producing clinical evidence of efficacy and safety of medical interventions. More recently, a new paradigm is emerging - specifically within the context of preauthorization regulatory decision-making - for some novel uses of real-world evidence (RWE) from a variety of real-world data (RWD) sources to answer certain clinical questions. Traditionally reserved for rare diseases and other special circumstances, external controls (eg, historical controls) are recognized as a possible type of control arm for single-arm trials. However, creating and analyzing an external control arm using RWD can be challenging since design and analytics may not fully control for all systematic differences (biases). Nonetheless, certain biases can be attenuated using appropriate design and analytical approaches. The main objective of this paper is to improve the scientific rigor in the generation of external control arms using RWD. Here we (a) discuss the rationale and regulatory circumstances appropriate for external control arms, (b) define different types of external control arms, and (c) describe study design elements and approaches to mitigate certain biases in external control arms. This manuscript received endorsement from the International Society for Pharmacoepidemiology (ISPE). Copyright 2020 The Authors.
    • Haptoglobin Therapeutics and Compartmentalization of Cell-Free Hemoglobin Toxicity

      Buehler, P.W.; Humar, R.; Schaer, D.J. (Elsevier Ltd, 2020)
      Hemolysis and accumulation of cell-free hemoglobin (Hb) in the circulation or in confined tissue compartments such as the subarachnoid space is an important driver of disease. Haptoglobin is the Hb binding and clearance protein in human plasma and an efficient antagonist of Hb toxicity resulting from physiological red blood cell turnover. However, endogenous concentrations of haptoglobin are insufficient to provide protection against Hb-driven disease processes in conditions such as sickle cell anemia, sepsis, transfusion reactions, medical-device associated hemolysis, or after a subarachnoid hemorrhage. As a result, there is increasing interest in developing haptoglobin therapeutics to target 'toxic' cell-free Hb exposures. Here, we discuss key concepts of Hb toxicity and provide a perspective on the use of haptoglobin as a therapeutic protein. Copyright 2020 The Authors
    • Evidence that brain-reactive autoantibodies contribute to chronic neuronal internalization of exogenous Amyloid-β1-42 and key cell surface proteins during Alzheimer's disease pathogenesis

      Goldwaser, E.L.; Acharya, N.K.; Wu, H. (IOS Press, 2020)
      Blood-brain barrier (BBB) permeability is a recognized early feature of Alzheimer’s disease (AD). In the present study, we examined consequences of increased BBB permeability on the development of AD-related pathology by tracking selected leaked plasma components and their interactions with neurons in vivo and in vitro. Histological sections of cortical regions of postmortem AD brains were immunostained to determine the distribution of amyloid-β1-42 (Aβ42), cathepsin D, IgG, GluR2/3, and alpha7 nicotinic acetylcholine receptor (α7nAChR). Results revealed that chronic IgG binding to pyramidal neurons coincided with internalization of Aβ42, IgG, GluR2/3, and α7nAChR as well as lysosomal compartment expansion in these cells in regions of AD pathology. To test possible mechanistic interrelationships of these phenomena, we exposed differentiated SH-SY5Y neuroblastoma cells to exogenous, soluble Aβ42 peptide and serum from AD and control subjects. The rate and extent of Aβ42 internalization in these cells was enhanced by serum containing neuron-binding IgG autoantibodies. This was confirmed by treating cells with individual antibodies specific for α7nAChR, purified IgG from AD or non-AD sera, and sera devoid of IgG, in the presence of 100 nM Aβ42. Initial co-localization of IgG, α7nAChR, and Aβ42 was temporally and spatially linked to early endosomes (Rab11) and later to lysosomes (LAMP-1). Aβ42 internalization was attenuated by treatment with monovalent F(ab) antibody fragments generated from purified IgG from AD serum and then rescued by coupling F(ab) fragments with divalent human anti-Fab. Overall, results suggest that cross-linking of neuron-binding autoantibodies targeting cell surface proteins can accelerate intraneuronal Aβ42 deposition in AD.