The molecular determinants of classical pathway complement inhibition by OspEF-related proteins of Borrelia burgdorferi.

The complement system serves as the first line of defense against invading pathogens by promoting opsonophagocytosis and bacteriolysis. Antibody-dependent activation of complement occurs through the classical pathway and relies on the activity of initiating complement proteases of the C1 complex, C1r and C1s. The causative agent of Lyme disease, Borrelia burgdorferi, expresses two paralogous outer surface lipoproteins of the OspEF-related protein family, ElpB and ElpQ, that act as specific inhibitors of classical pathway activation. We have previously shown that ElpB and ElpQ bind directly to C1r and C1s with high affinity and specifically inhibit C2 and C4 cleavage by C1s. To further understand how these novel protease inhibitors function, we carried out a series of hydrogen-deuterium exchange mass spectrometry (HDX-MS) experiments using ElpQ and full-length activated C1s as a model of Elp-protease interaction. Comparison of HDX-MS profiles between unbound ElpQ and the ElpQ/C1s complex revealed a putative C1s-binding site on ElpQ. HDX-MS-guided, site-directed ElpQ mutants were generated and tested for direct binding to C1r and C1s using surface plasmon resonance. Several residues within the C-terminal region of ElpQ were identified as important for protease binding, including a single conserved tyrosine residue that was required for ElpQ- and ElpB-mediated complement inhibition. Collectively, our study identifies key molecular determinants for classical pathway protease recognition by Elp proteins. This investigation improves our understanding of the unique complement inhibitory mechanism employed by Elp proteins which serve as part of a sophisticated complement evasion system present in Lyme disease spirochetes.

Outer surface lipoproteins from the Lyme disease spirochete exploit the molecular switch mechanism of the complement protease C1s.

Proteolytic cascades comprise several important physiological systems, including a primary arm of innate immunity called the complement cascade. To safeguard against complement-mediated attack, the etiologic agent of Lyme disease, Borreliella burgdorferi, produces numerous outer surface-localized lipoproteins that contribute to successful complement evasion. Recently, we discovered a pair of B. burgdorferi surface lipoproteins of the OspEF-related protein family-termed ElpB and ElpQ-that inhibit antibody-mediated complement activation. In this study, we investigate the molecular mechanism of ElpB and ElpQ complement inhibition using an array of biochemical and biophysical approaches. In vitro assays of complement activation show that an independently folded homologous C-terminal domain of each Elp protein maintains full complement inhibitory activity and selectively inhibits the classical pathway. Using binding assays and complement component C1s enzyme assays, we show that binding of Elp proteins to activated C1s blocks complement component C4 cleavage by competing with C1s-C4 binding without occluding the active site. C1s-mediated C4 cleavage is dependent on activation-induced binding sites, termed exosites. To test whether these exosites are involved in Elp-C1s binding, we performed site-directed mutagenesis, which showed that ElpB and ElpQ binding require C1s residues in the anion-binding exosite located on the serine protease domain of C1s. Based on these results, we propose a model whereby ElpB and ElpQ exploit activation-induced conformational changes that are normally important for C1s-mediated C4 cleavage. Our study expands the known complement evasion mechanisms of microbial pathogens and reveals a novel molecular mechanism for selective C1s inhibition by Lyme disease spirochetes.

Clinical trial transparency in gastrointestinal endoscopy research.

BACKGROUND: Under-reporting of clinical trial results can lead to negative consequences that include inhibiting propagation of knowledge, limiting the understanding of how devices work, affecting conclusions of meta-analyses, and failing to acknowledge patient participation. Therefore clinical trial transparency, through publication of trial results on ClinicalTrials.gov or in manuscript form, is important. We aimed to examine clinical trial transparency in endoscopic clinical trials. METHODS: The ClinicalTrials.gov database was searched for endoscopy trials up to October 2019. Adherence to the reporting of results to the database or in publication form was recorded for each trial. RESULTS: The final analysis included 923 trials, of which 801 were completed and 122 were either terminated or suspended. Results were available either on ClinicalTrials.gov or in publication for 751/923 trials (81.4 %). Other fields have reported a publication rate of 40 %-63 %. Results were available on ClinicalTrials.gov for 168 trials (18.2 %) and in the form of a publication for 720 trails (78.0 %). CONCLUSIONS: Compared with other fields in medicine, endoscopy clinical trials have a high rate of clinical trial transparency. However, there is room for improvements as close to one-fifth of trials fail to report results and 81.8 % do not report results to ClinicalTrials.gov.

Birth plans: definitions, content, effects, and best practices.

The first written guide for birth plans was introduced in 1980 as a means for birthing people to document their choices in the child birthing experience. The birth plan offers an opportunity for the patient and the provider to discuss the birthing process and determine how to safely accommodate patient preferences. Patient satisfaction with birthing plans is variable and may depend on how many requests they have, how many of their plans are accomplished, route of delivery, and whether complications arise during or after delivery. Unmet expectations may lead to posttraumatic stress disorder, but following a birth plan may also be protective against it. Birthing people who use a birth plan may be less likely to use epidural anesthesia, have early amniotomy, or use oxytocin. The first stage of labor may be longer when a birth plan is used; however, there does not seem to be a decrease in the length of the second stage of labor among patients with a birth plan. Some providers believe that a disadvantage of birth plans is disappointment when birth plans are not able to be followed, and others consider that birth plans interfere with professional autonomy.

Gastroenterology Clinical Trials Transparency: An Analysis of Publication Rates From the ClinicalTrials.gov Database.

INTRODUCTION: There is limited information on the transparency of gastroenterology clinical trials. METHODS: The ClinicalTrials.gov database was searched for trials focused on most common gastrointestinal diseases up to August 2018. Adherence to reporting of results to the database or in publication form was recorded for each trial along with trial characteristics. RESULTS: Of the 2,429 trials included in the final analysis, 1824 (75%, 95% confidence interval: 73.4%-76.8%) had results on ClinicalTrials.gov or in the form of a publication. However, only 534 (29%) had results posted on ClinicalTrials.gov. DISCUSSION: Improvement of clinical trial transparency is needed in gastroenterology.

Spatial distribution of dysplasia in Barrett's esophagus segments before and after endoscopic ablation therapy: a meta-analysis.

BACKGROUND: Dysplasia in Barrett's esophagus (BE) is focal and difficult to locate. The aim of this meta-analysis was to understand the spatial distribution of dysplasia in BE before and after endoscopic ablation therapy. METHODS: A systematic search was performed of multiple databases to July 2019. The location of dysplasia prior to ablation was determined using a clock-face orientation (right or left half of the esophagus). The location of the dysplasia post-ablation was classified as within the tubular esophagus or at the top of the gastric folds (TGF). RESULTS: 13 studies with 2234 patients were analyzed. Pooled analysis from six studies (819 lesions in 802 patients) showed that before ablation, dysplasia was more commonly located in the right half versus the left half (odds ratio [OR] 4.3; 95 % confidence interval [CI] 2.33 - 7.93; P < 0.001). Pooled analysis from seven studies showed that dysplasia after ablation recurred in 101 /1432 patients (7.05 %; 95 %CI 5.7 % - 8.4 %). Recurrence of dysplasia was located more commonly at the TGF (n = 68) than in the tubular esophagus (n = 34; OR 5.33; 95 %CI 1.75 - 16.21; P = 0.003). Of the esophageal lesions, 90 % (27 /30) were visible, whereas only 46 % (23 /50) of the recurrent dysplastic lesions at the TGF were visible (P < 0.001). CONCLUSION: Before ablation, dysplasia in BE is found more frequently in the right half of the esophagus versus the left. Post-ablation recurrence is more commonly found in the TGF and is non-visible, compared with the tubular esophagus, which is mainly visible.

Delays in anti-hyperglycaemic therapy initiation and intensification are associated with cardiovascular events, hospitalizations for heart failure and all-cause mortality.

AIMS: The aims of this study were to assess the impact of delays in treatment intensification (TI) on cardiovascular events, heart failure, and all-cause mortality at typical stages of anti-hyperglycaemic therapy. MATERIALS AND METHODS: Using electronic health record data, we created three TI cohorts of diabetes patients who: 1) initiated metformin (MET) as their first anti-hyperglycaemic therapy; 2) added a sulfonylurea (SU) to MET; and 3) initiated insulin (INS) while using MET or SU, alone or in combination. Primary exposure variables were haemoglobin A1C value preceding cohort therapy (pre-TI A1C) and time to intensification, that is, the time between pre-TI A1C >7% and cohort index date. Cox regression models were used to analyse the associated risk of cardiovascular events, hospitalizations for heart failure and all-cause mortality. RESULTS: In the MET cohort, each additional percentage point of pre-TI A1C was associated with a 10% increased risk of a CV event (HR, 1.10; 95% CI, 1.03-1.07; P = 0.004), a 7% increased risk of HF hospitalization (HR, 1.07; 95% CI, 1.01-1.14; P = 0.034) and a 7% increased risk of all-cause mortality (HR, 1.07; 95% CI, 1.01-1.14; P = 0.032). Pre-TI A1C was associated with a 9% increased risk of a CV event in the INS cohort (HR,1.09; 95% CI, 1.04-1.13; P < 0.001). Each month of delay in TI was significantly associated with a 6% increased risk of hospitalization for HF (HR, 1.06; 95% CI, 1.00-1.13; P = 0.040) and all-cause mortality (HR, 1.06; 95% CI, 1.00-1.13; P = 0.050) in the MET cohort. CONCLUSIONS: Delays in TI were associated with poor outcomes over a mean follow-up period of nearly five years. Earlier initiation and more rapid intensification of pharmacotherapy could reduce the risk of poor outcomes.

Longitudinal changes in glycated haemoglobin following treatment intensification after inadequate response to two oral antidiabetic agents in patients with type 2 diabetes.

AIMS: To identify change in glycated haemoglobin (HbA1c) for 1 year after treatment intensification in patients with HbA1c >53 mmol/mol (7.0%) while on two classes of oral antidiabetic drugs (OADs). MATERIAL AND METHODS: A retrospective cohort study was conducted using a regional health plan claims database for the period January 1, 2010 to March 31, 2017. Patients with type 2 diabetes (T2DM) whose treatment was intensified with insulin, a glucagon-like peptide-1 receptor agonist or a third OAD within 365 days of having HbA1c ≥53 mmol/mol (7.0%) on two OADs were included. The HbA1c trajectory for 1 year after intensification was estimated using a mixed-effects regression model. RESULTS: The analysis included 1226 patients with a mean ± SD HbA1c at treatment intensification of 74.2 ± 18.7 mmol/mol (8.93 ± 1.7%). HbA1c was higher in the insulin group (74.2 mmol/mol) than in the non-insulin group (70.6 mmol/mol), as was the HbA1c decrease (P < 0.01) over the 1-year follow-up, particularly in patients with baseline HbA1c >9%. After intensification, insulin- and non-insulin-treated patients achieved an average change by month in HbA1c of -4.7 mmol/mol and -2.6 mmol/mol points, respectively. The analysis predicted HbA1c to be the lowest at 6 to 10 months post intensification, depending on intensification treatment and HbA1c at intensification; however, on average, HbA1c remained above 64.0 mmol/mol (8.0%). CONCLUSION: In patients with T2DM, intensification following an HbA1c value ≥53 mmol/mol (7.0%) while on two OADs was associated with a significant improvement in glycaemic control. Patients intensified with insulin had a higher baseline HbA1c but greater HbA1c reduction than those intensified with a non-insulin agent. However, HbA1c remained above 64 mmol/mol (8.0%) overall. Additional opportunity exists to further intensify therapy to improve glycaemic control.

Medical School Home Page Library Links: What Has Changed Since 2010.

The purpose of this study was to compare the visibility and placement of links to the library on home pages of 165 American Association of Medical Colleges member medical schools with the results from a study performed in 2010. Visibility on the home page declined from 50.7% to 41.2%, and one-click pathways declined from 61% to 44.8%. On 14 medical school websites, no discoverable navigation to the library could be found, including use of the search function. During the same time period, librarian partnerships with health care professionals and biomedical researchers have increased and expanded.

Beginning the Work of Integration: An Investigation of Primary Care Physicians' Attitudes Toward Psychiatry.

OBJECTIVE: The authors sought to better understand the attitudes of primary care physicians toward psychiatrists in order to assess their receptivity for further psychiatric education. METHODS: A survey about attitudes toward psychiatrists in comparison to other specialties was distributed among four family medicine residency programs at Southern Illinois University. RESULTS: Respondents rated psychiatry lower than other specialties in the areas measured. However, family medicine physicians expressed a desire to work with psychiatrists and receive further education in psychiatry. CONCLUSION: Favorable attitudes toward psychiatrists and education in psychiatry suggest the potential for additional family medicine training in psychiatry.

Academic health sciences librarians' contributions to institutional animal care and use committees.

The study gathered data about librarians' membership in institutional animal care and use committees (IACUCs) and their professional activities supporting animal researchers. Libraries affiliated with medical schools that were members of the Association of American Medical Colleges were surveyed. A survey was distributed via library directors' email discussion lists and direct email messages. Sixty surveys were completed: 35 (58%) reported that librarians performed database searches for researchers, and 22 (37%) reported that a librarian currently serves on the IACUC. The survey suggests that academic health sciences librarians provide valuable, yet underutilized, services to support animal research investigators.

Breast cancer fear in African American breast cancer survivors.

The purpose of this study was to describe breast cancer fear according to phase of survivorship, determine whether breast cancer fear levels differed among survivorship phases, and determine the relationship between fear and age in African-American breast cancer survivors. The study utilized secondary data analysis from the study, Inner Resources as Predictors of Psychological Well-Being in AABCS. A new subscale entitled, "Breast Cancer Fear" was adapted from the Psychological Well Being Subscale by Ferrell and Grant. There was no significant difference between fear and phase of survivorship. There was a significant positive relationship between age and fear.

Antibodies to coagulase of Staphylococcus aureus crossreact to Efb and reveal different binding of shared fibrinogen binding repeats.

Staphylococcus aureus pathology is caused by a plethora of virulence factors able to combat multiple host defence mechanisms. Fibrinogen (Fg), a critical component in the host coagulation cascade, plays an important role in the pathogenesis of this bacterium, as it is the target of numerous staphylococcal virulence proteins. Amongst its secreted virulence factors, coagulase (Coa) and Extracellular fibrinogen-binding protein (Efb) share common Fg binding motives and have been described to form a Fg shield around staphylococcal cells, thereby allowing efficient bacterial spreading, phagocytosis escape and evasion of host immune system responses. Targeting these proteins with monoclonal antibodies thus represents a new therapeutic option against S. aureus. To this end, here we report the selection and characterization of fully human, sequence-defined, monoclonal antibodies selected against the C-terminal of coagulase. Given the functional homology between Coa and Efb, we also investigated if the generated antibodies bound the two virulence factors. Thirteen unique antibodies were isolated from naïve antibodies gene libraries by antibody phage display. As anticipated, most of the selected antibodies showed cross-recognition of these two proteins and among them, four were able to block the interaction between Coa/Efb and Fg. Furthermore, our monoclonal antibodies could interact with the two main Fg binding repeats present at the C-terminal of Coa and distinguish them, suggesting the presence of two functionally different Fg-binding epitopes.

Factors Related to Biologic Adherence and Outcomes Among Moderate-to-Severe Asthma Patients.

BACKGROUND: Adherence barriers to asthma biologics may not be uniform across administration settings for patients with moderate-to-severe asthma. OBJECTIVE: To examine differences in asthma biologic adherence and associated factors, as well as association with a 1-year all-cause emergency department (ED) visit, across administration settings. METHODS: A retrospective study of biologic naïve moderate-to-severe asthma patients with initial biologic therapy between January 1, 2016, and April 30, 2020, in the Optum Clinformatics Data Mart was performed. Three administration settings were identified: Clinic-only (outpatient office/infusion center), Home (self-administration), and Hybrid setting (mixture of clinic and self-administration). Asthma biologic adherence was the proportion of observed over expected biologic dose administrations received within 6 months from initial therapy. Factors associated with adherence were identified by administration setting, using Poisson regression analyses. A relationship between a 1-year all-cause ED visit and adherence was assessed for each administration setting using Cox regression analyses. RESULTS: The study cohort was 3932 patients. Biologics adherence was 0.75 [0.5, 1] in Clinic setting, the most common administration setting, and 0.83 [0.5, 1] in both Home and Hybrid settings. Specialist access was consistently associated with better biologic adherence, whereas Black race, Hispanic ethnicity, lower education, Medicare only insurance, and higher patient out-of-pocket cost were associated with worse biologic adherence in some settings. In the Hybrid setting, hazard for a 1-year all-cause ED visit decreased with biologic adherence. CONCLUSIONS: Asthma biologic adherence varied by administration setting. Efforts to improve asthma biologic adherence should consider promoting self-administration when beneficial, improving prior specialist access, and targeting patients with higher risk of suboptimal adherence particularly Black and Hispanic patients.

Adaptation and Testing of a Military Version of the Measure of Moral Distress for Healthcare Professionals.

BACKGROUND: Moral distress is well-documented among civilian critical care nurses and adversely affects patient outcomes, care delivery, and retention of health care providers. Despite its recognized significance, few studies have addressed moral distress in military critical care nurses. OBJECTIVES: To refine and validate an instrument to assess moral distress in military critical care nurses. METHODS: This study examined moral distress in military critical care nurses (N = 245) using a new instrument, the Measure of Moral Distress for Healthcare Professionals-Military (MMD-HP-M). The psychometric properties of the refined scale were assessed by use of descriptive statistics, tests of reliability and validity, exploratory factor analysis, correlations, and qualitative analysis of open-ended responses. RESULTS: Initial testing showed promising evidence of instrument performance. The Cronbach α (0.94) suggested good internal consistency of the instrument for the overall sample. Scores for the MMD-HP items and the MMD-HP-M items showed a strong, significant correlation (α= 0.78, P < .001). Unique attributes of military nursing that contribute to moral distress included resource access, futile care, and austere conditions. Exploratory factor analysis established a new military-centric factor for question items associated with inadequate training for patient care, providing care in resource-limited settings, and personal exhaustion. CONCLUSIONS: These results will help guide specific, targeted interventions to reduce the negative effects of moral distress on our military health care providers, especially in terms of readiness for the next global pandemic and retention of these invaluable personnel.

An Shp2/SFK/Ras/Erk signaling pathway controls trophoblast stem cell survival.

Little is known about how growth factors control tissue stem cell survival and proliferation. We analyzed mice with a null mutation of Shp2 (Ptpn11), a key component of receptor tyrosine kinase signaling. Null embryos die peri-implantation, much earlier than mice that express an Shp2 truncation. Shp2 null blastocysts initially develop normally, but they subsequently exhibit inner cell mass death, diminished numbers of trophoblast giant cells, and failure to yield trophoblast stem (TS) cell lines. Molecular markers reveal that the trophoblast lineage, which requires fibroblast growth factor-4 (FGF4), is specified but fails to expand normally. Moreover, deletion of Shp2 in TS cells causes rapid apoptosis. We show that Shp2 is required for FGF4-evoked activation of the Src/Ras/Erk pathway that culminates in phosphorylation and destabilization of the proapoptotic protein Bim. Bim depletion substantially blocks apoptosis and significantly restores Shp2 null TS cell proliferation, thereby establishing a key mechanism by which FGF4 controls stem cell survival.

FAK-Src signalling through paxillin, ERK and MLCK regulates adhesion disassembly.

Cell migration is a complex, highly regulated process that involves the continuous formation and disassembly of adhesions (adhesion turnover). Adhesion formation takes place at the leading edge of protrusions, whereas disassembly occurs both at the cell rear and at the base of protrusions. Despite the importance of these processes in migration, the mechanisms that regulate adhesion formation and disassembly remain largely unknown. Here we develop quantitative assays to measure the rate of incorporation of molecules into adhesions and the departure of these proteins from adhesions. Using these assays, we show that kinases and adaptor molecules, including focal adhesion kinase (FAK), Src, p130CAS, paxillin, extracellular signal-regulated kinase (ERK) and myosin light-chain kinase (MLCK) are critical for adhesion turnover at the cell front, a process central to migration.

Library links on medical school home pages.

The purpose of this study was to assess the websites of American Association of Medical Colleges (AAMC)-member medical schools for the presence of library links. Sixty-one percent (n = 92) of home pages of the 150 member schools of the AAMC contain library links. For the 58 home pages not offering such links, 50 provided a pathway of two or three clicks to a library link. The absence of library links on 39% of AAMC medical school home pages indicates that the designers of those pages did not consider the library to be a primary destination for their visitors.

vhp Is a Fibrinogen-Binding Protein Related to vWbp in Staphylococcus aureus.

Staphylococcus aureus can target a variety of tissues, causing life-threatening infections. The basis for this diversity stems from the microorganism's ability to spread in the vascular system throughout the body. To survive in blood, S. aureus coats itself with a fibrinogen (Fg)/fibrin shield. The protective shield is assembled by the coordinated actions of a number of Fg-binding bacterial proteins that manipulate the host's blood coagulation system. Several of the Fg binders appear redundant, sharing similar functional motifs. This observation led us to screen for the presence of novel proteins with significant amino acid identities to von Willebrand factor-binding protein (vWbp), a key component in the shield assembly machinery. One identified protein showed significant sequence identity with the C-terminal region of vWbp, and we consequently named it vWbp homologous protein (vhp). The vhp gene lies within a cluster of genes that encode other virulence factors in S. aureus. Although each isolate only contains one copy of the vhp gene, S. aureus has at least three distinct alleles, vhpA, B, and C, that are present in the core genome. All three vhp isoforms bind Fg with high affinity, targeting a site located in the D fragment of Fg. We further identified an ∼79 amino acid-long, conserved segment within the C-terminal region of vWbp that shares high sequence identities (54 to 67%) with the vhps and binds soluble Fg with high affinity. Further analysis of this conserved motif and the intact vhps revealed intriguing differences in the Fg binding behavior, perhaps suggesting that these proteins have similar but discrete functions in the shield assembly. IMPORTANCE The life-threatening diseases caused by multidrug-resistant Staphylococcus aureus strains are a worldwide medical problem due to treatment limitations and the lack of an effective vaccine. The ability of S. aureus to coat itself with a protective fibrinogen (Fg)/fibrin shield allows the organism to survive in blood and to disseminate and cause invasive diseases. This process represents a promising target for novel antistaphylococcal treatment strategies but is incompletely understood. S. aureus expresses a number of Fg-binding proteins. Some of these proteins have apparently redundant functions. Proteins with similar functions often share a structural or functional motif with each other. In this study, we identified a protein homologous to the C-terminal of von Willebrand factor-binding protein (vWbp), a key contributor in the Fg shield assembly that also binds Fg. Further analysis allowed us to identify a common Fg-binding motif.

Therapeutic Inertia in Prescribing Biologics for Patients with Moderate-to-Severe Asthma: Workshop Summary.

Moderate-to-severe asthma represents about a quarter of the nearly 10% of Americans diagnosed with asthma. Many patients with moderate-to-severe asthma have uncontrolled symptoms that lead to exacerbations requiring oral corticosteroids. There are many factors contributing to poor asthma control, including poor adherence to prescribed therapies, the under-prescribing of biologics and therapeutic inertia. We convened an eight-member panel from fields of primary care, pulmonology, immunology, health services and clinical research, behavioral science and pharmaceutical medical affairs, with the goal of identifying contributing factors and solutions to therapeutic inertia with asthma biologics. We used the Capability, Opportunity, and Motivation (COM-B) model to classify patient and provider behavior towards therapeutic inertia. The model incorporates existing behavior theories and is driven by the interaction of capability, opportunity, and motivation. We used a Delphi method to identify and develop six primary solutions: 1) integration of patient-centered outcomes into asthma management practice; 2) provider education about asthma treatment; 3) moderate-to-severe asthma care delivery redesign; 4) harmonized, evidence-based protocol for the management of moderate-to-severe asthma; 5) designated coordinator approach for optimal asthma management; and 6) a case coordination digital support tool. Integration of patient-centered outcomes into asthma management practice and provider education were identified as having the highest potential to impact therapeutic and clinical inertia. The COM-B model is effective in identifying improvement within therapeutic inertia targeting the capabilities, opportunities, and motivations of patients, providers, and payer systems.