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High-parameter phenotypic characterization reveals a subset of human Th17 cells that preferentially produce IL17 against M. tuberculosis antigen.

Interleukin 17 producing CD4 T cells contribute to the control of Mycobacterium tuberculosis (Mtb) infection in humans; whether infection with Human Immunodeficiency Virus (HIV) disproportionately affects distinct Th17 cell subsets that respond to Mtb is incompletely defined. We performed high-definition characterization of circulating Mtb-specific Th17 cells by spectral flow cytometry in people with latent TB and treated HIV (HIV-ART). We also measured kynurenine pathway activity by LC/MS on plasma and tested the hypothesis that tryptophan catabolism influences Th17 cell frequencies in this context. We identified two subsets of Th17 cells: subset 1 defined as CD4+Vα7.2-CD161+CD26+ and subset 2 defined as CD4+Vα7.2-CCR6+CXCR3- cells of which subset 1 was significantly reduced in LTBI with HIV-ART, yet Mtb-responsive IL17-producing CD4 T cells were preserved; we found that IL17-producing CD4 T cells dominate the response to Mtb antigen but not CMV antigen or staphylococcal enterotoxin B (SEB); and tryptophan catabolism negatively correlates with both subset 1 and subset 2 Th17 cell frequencies. We found differential effects of ART-suppressed HIV on distinct subsets of Th17 cells, that IL17-producing CD4 T cells dominate responses to Mtb but not CMV antigen or SEB, and that kynurenine pathway activity is associated with decreases of circulating Th17 cells that may contribute to tuberculosis immunity.

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Safety and Outcomes of Outpatient Pleural Drainage in Symptomatic Postoperative Cardiac Surgery Patients.

Symptomatic pleural effusions and anticoagulant/antiplatelet medication use in postoperative cardiac surgery are common. Guidelines and recommendations are currently mixed regarding medication management related to invasive procedure performance. We aimed to describe the outcomes of postoperative cardiac surgery patients referred for outpatient, symptomatic pleural effusion management. A retrospective study of post-cardiac surgery patients undergoing outpatient thoracentesis from 2016 to 2021 was performed. Demographics, operative details, pleural disease characteristics, outcomes, and complications were collected. Odds ratios with confidence intervals were estimated and adjusted by multivariate logistic regression to investigate the association with multiple thoracenteses. A total of 110 patients underwent 332 thoracenteses. The median age was 68 years and most common operation was coronary artery bypass. Anticoagulation or antiplatelet use was identified in 97%. Thirteen complications were identified, with all major complications (n=3) related to bleeding. The amount of fluid present at the time of initial thoracentesis (>1500 milliliters) was associated with increased odds ratio of subsequent multiple thoracentesis (Unadjusted odds ratio, 6.75 (CI - 1.43 to 31.9). No other variables had a significant association with the need for multiple procedures. Within a postoperative cardiac surgery population presenting with symptomatic pleural disease, we observed that thoracentesis performed on antiplatelet and/or anticoagulant medication is relatively safe. We also identified that many patients can be managed as outpatients and that most pleural effusions remain self-limited. The presence of larger amounts of pleural fluid at initial thoracentesis may be associated with increased odds for additional drainage.

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Enablers and barriers to engaging under-served groups in research: Survey of the United Kingdom research professional’s views

Background There is a known lack of diversity in research participant populations. This impacts on the generalisability of findings and affects clinician prescribing. In the United Kingdom the research community defines those who are underrepresented as under-served. They are commonly those affected by health inequality and disparity. The notion of under-served is complex, with numerous papers identifying multiple factors that contribute to being under-served and in turn suggesting many strategies to improve engagement. Methods Research professionals in the UK were invited to complete an online survey. The broad aim was to explore their views on under-served groups. The findings were analysed using statistical and qualitative methods to identify enablers and barriers to engaging the under-served. Descriptive statistics were utilised with associations compared univariately by chi-square test and logistic regression for multivariable analysis. Results A total of 945 completed responses were received. Those identified as under-served in this study reflected the previous body of works with a broader descriptor of ethnic and cultural minorities and the addition of adolescents and young adults. Language and literacy skills had the most impact on being under-served. Only 13% of respondents said they felt equipped to meet the needs of the under-served. The main strategy to increase diversity was community engagement and movement of research delivery into the community. The barriers were funding and time. Training needs identified were linked to community engagement, cultural competence and consent processes. Conclusions The UK findings from research professionals reflected the previous literature. Adolescents and young people were added to those identified as under-served. Enablers included community outreach and improvement to communication. Barriers were time, funding, organisational processes and lack of focus. Issues were identified with translation and interpretation services. Training requirements focus on methodologies and methods to engage and the consent processes of those from under-served groups.

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Postpartum care: Discussions and counseling for the peripartum period.

Traditionally, postpartum care is confined to inpatient care immediately post birth and one appointment approximately six weeks postpartum. Data supports a continuum of care model as best for the health of mother and baby. Despite most women having significant concerns about the postpartum period, these concerns are frequently incompletely addressed by providers. We surveyed prenatal and postpartum patients to understand their concerns and experiences discussing postpartum care with providers. Cross sectional surveys were administered between June 2019 and May 2021. Principal component analysis was used to show higher than average (positive) or lower than average (negative) conversations with providers about postpartum care examined by race, education, and parity. Chi squared tests were conducted to examine the significance of specific postpartum concerns. 421/450 patient surveys were analyzed, based on completion. Most patients were White (193), had post graduate degrees (188), privately insured (236), married (248), first time pregnant (152), and used doctors as their primary provider (267). Patients with lower education, higher parity and Black patients without postgraduate degrees reported higher than average postpartum counseling. Additionally, most patients expressed significant concerns about postpartum exhaustion (65.8%), breastfeeding (62.3%), pain (61.2%), physical activity (54.9%) and the baby blues (50.4%). Postpartum concerns are incompletely and inconsistently addressed amongst patients based on race, parity, and education. A continuum of care approach, beginning in the third trimester, through the postpartum period, may provide better counseling to address all patients' concerns.

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Low factor XIII levels and altered fibrinolysis in patients with multiple myeloma

BackgroundAcquired factor FXIII (FXIII) deficiency can be immune- or non-immune mediated and may cause severe bleeding symptoms. The incidence of acquired FXIII deficiency and its etiology in patients with multiple myeloma (MM) are poorly understood. ObjectivesTo assess FXIII levels and the balance of fibrinolysis in newly diagnosed, untreated MM and monoclonal gammopathy of undetermined significance (MGUS) patients. MethodsFXIII activity, mixing studies, FXIII-A2B2 antigen, total FXIII-B antigen were measured in platelet-poor plasma from 17 untreated MM patients, 33 untreated MGUS patients, and 30 age and sex-matched healthy controls. Besides routine laboratory measurements, the balance of coagulation and fibrinolysis was evaluated using quantitative fibrin monomer (FM) test, thrombin-antithrombin assay, α2-antiplasmin activity, plasmin-α2-antiplasmin (PAP) complex, D-dimer, plasmin generation assay, clot lysis assay, and ClotPro-TPA test. ResultsFXIII-A2B2 levels were significantly lower in MM patients compared to controls [median (IQR):14.6 (11.2–19.4) vs. 21.8 (17.1–26.4) mg/L, p = 0.0015], whereas total FXIII-B did not differ between groups. Decrease in FXIII activity was parallel to the decrease in FXIII-A2B2. An immune-mediated inhibitory mechanism was ruled out. Free/total FXIII-B was significantly higher in MM patients compared to MGUS and healthy controls, suggesting an etiology of FXIII-A consumption. In MM and MGUS patients, FM, D-dimer, and PAP complex were significantly elevated compared to controls, indicating hypercoagulability and ongoing fibrinolysis. ConclusionsLow FXIII levels due to consumption were observed in MM patients at diagnosis. Hypercoagulability and ongoing fibrinolysis were detected in MM and MGUS, indicating that a disturbed hemostasis balance is already present in the latter benign condition.

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Dynamic behaviour restructuring mediates dopamine-dependent credit assignment

Animals exhibit a diverse behavioural repertoire when exploring new environments and can learn which actions or action sequences produce positive outcomes. Dopamine release after encountering a reward is critical for reinforcing reward-producing actions1–3. However, it has been challenging to understand how credit is assigned to the exact action that produced the dopamine release during continuous behaviour. Here we investigated this problem in mice using a self-stimulation paradigm in which specific spontaneous movements triggered optogenetic stimulation of dopaminergic neurons. Dopamine self-stimulation rapidly and dynamically changes the structure of the entire behavioural repertoire. Initial stimulations reinforced not only the stimulation-producing target action, but also actions similar to the target action and actions that occurred a few seconds before stimulation. Repeated pairings led to a gradual refinement of the behavioural repertoire to home in on the target action. Reinforcement of action sequences revealed further temporal dependencies of refinement. Action pairs spontaneously separated by long time intervals promoted a stepwise credit assignment, with early refinement of actions most proximal to stimulation and subsequent refinement of more distal actions. Thus, a retrospective reinforcement mechanism promotes not only reinforcement, but also gradual refinement of the entire behavioural repertoire to assign credit to specific actions and action sequences that lead to dopamine release.

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α-Synuclein pathology disrupts mitochondrial function in dopaminergic and cholinergic neurons at-risk in Parkinson's disease.

Pathological accumulation of aggregated α-synuclein (aSYN) is a common feature of Parkinson's disease (PD). However, the mechanisms by which intracellular aSYN pathology contributes to dysfunction and degeneration of neurons in the brain are still unclear. A potentially relevant target of aSYN is the mitochondrion. To test this hypothesis, genetic and physiological methods were used to monitor mitochondrial function in substantia nigra pars compacta (SNc) dopaminergic and pedunculopontine nucleus (PPN) cholinergic neurons after stereotaxic injection of aSYN pre-formed fibrils (PFFs) into the mouse brain. aSYN PPFs were stereotaxically injected into the SNc or PPN of mice. Twelve weeks later, mice were studied using a combination of approaches, including immunocytochemical analysis, cell- type specific transcriptomic profiling, electron microscopy, electrophysiology and two-photon-laser- scanning microscopy of genetically encoded sensors for bioenergetic and redox status. In addition to inducing a significant neuronal loss, SNc injection of PFFs induced the formation of intracellular, phosphorylated aSYN aggregates selectively in dopaminergic neurons. In these neurons, PFF-exposure decreased mitochondrial gene expression, reduced the number of mitochondria, increased oxidant stress, and profoundly disrupted mitochondrial adenosine triphosphate production. Consistent with an aSYN-induced bioenergetic deficit, the autonomous spiking of dopaminergic neurons slowed or stopped. PFFs also up-regulated lysosomal gene expression and increased lysosomal abundance, leading to the formation of Lewy-like inclusions. Similar changes were observed in PPN cholinergic neurons following aSYN PFF exposure. Taken together, our findings suggest that disruption of mitochondrial function, and the subsequent bioenergetic deficit, is a proximal step in the cascade of events induced by aSYN pathology leading to dysfunction and degeneration of neurons at-risk in PD.

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