Multipotent mesenchymal stromal cells (MSCs) ameliorate a wide range of diseases in preclinical models, but the lack of clarity around their mechanisms of action has impeded their clinical utility. ...The therapeutic effects of MSCs are often attributed to bioactive molecules secreted by viable MSCs. However, we found that MSCs underwent apoptosis in the lung after intravenous administration, even in the absence of host cytotoxic or alloreactive cells. Deletion of the apoptotic effectors BAK and BAX prevented MSC death and attenuated their immunosuppressive effects in disease models used to define MSC potency. Mechanistically, apoptosis of MSCs and their efferocytosis induced changes in metabolic and inflammatory pathways in alveolar macrophages to effect immunosuppression and reduce disease severity. Our data reveal a mode of action whereby the host response to dying MSCs is key to their therapeutic effects; findings that have broad implications for the effective translation of cell-based therapies.
B-lines evaluated by lung ultrasound (LUS) are the sonographic sign of pulmonary congestion, a major predictor of morbidity and mortality in patients with heart failure (HF). Our aim was to assess ...the prognostic value of B-lines at discharge to predict rehospitalization at 6 months in patients with acute HF (AHF).
A prospective cohort of 100 patients admitted to a Cardiology Department for dyspnea and/or clinical suspicion of AHF were enrolled (mean age 70 ± 11 years). B-lines were evaluated at admission and before discharge. Subjects were followed-up for 6-months after discharge.
Mean B-lines at admission was 48 ± 48 with a statistically significant reduction before discharge (20 ± 23, p < .0001). During follow-up, 14 patients were rehospitalized for decompensated HF. The 6-month event-free survival was highest in patients with less B-lines (≤ 15) and lowest in patients with more B-lines (> 15) (log rank χ(2) 20.5, p < .0001). On multivariable analysis, B-lines > 15 before discharge (hazard ratio HR 11.74; 95 % confidence interval CI 1.30-106.16) was an independent predictor of events at 6 months.
Persistent pulmonary congestion before discharge evaluated by ultrasound strongly predicts rehospitalization for HF at 6-months. Absence or a mild degree of B-lines identify a subgroup at extremely low risk to be readmitted for HF decompensation.
The global pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) is a highly pathogenic RNA virus causing coronavirus disease 2019 (COVID‐19) in humans. Although most ...patients with COVID‐19 have mild illness and may be asymptomatic, some will develop severe pneumonia, acute respiratory distress syndrome, multi‐organ failure, and death. RNA viruses such as SARS‐CoV‐2 are capable of hijacking the epigenetic landscape of host immune cells to evade antiviral defense. Yet, there remain considerable gaps in our understanding of immune cell epigenetic changes associated with severe SARS‐CoV‐2 infection pathology. Here, we examined genome‐wide DNA methylation (DNAm) profiles of peripheral blood mononuclear cells from 9 terminally‐ill, critical COVID‐19 patients with confirmed SARS‐CoV‐2 plasma viremia compared with uninfected, hospitalized influenza, untreated primary HIV infection, and mild/moderate COVID‐19 HIV coinfected individuals. Cell‐type deconvolution analyses confirmed lymphopenia in severe COVID‐19 and revealed a high percentage of estimated neutrophils suggesting perturbations to DNAm associated with granulopoiesis. We observed a distinct DNAm signature of severe COVID‐19 characterized by hypermethylation of IFN‐related genes and hypomethylation of inflammatory genes, reinforcing observations in infection models and single‐cell transcriptional studies of severe COVID‐19. Epigenetic clock analyses revealed severe COVID‐19 was associated with an increased DNAm age and elevated mortality risk according to GrimAge, further validating the epigenetic clock as a predictor of disease and mortality risk. Our epigenetic results reveal a discovery DNAm signature of severe COVID‐19 in blood potentially useful for corroborating clinical assessments, informing pathogenic mechanisms, and revealing new therapeutic targets against SARS‐CoV‐2.
Graphical
A distinct epigenetic signature associated with severe COVID‐19 exists in blood and is potentially useful for corroborating clinical assessments, informing pathogenic mechanisms, and revealing new therapeutic targets.
HIV-1 disrupts the host epigenetic landscape with consequences for disease pathogenesis, viral persistence, and HIV-associated comorbidities. Here, we examined how soon after infection HIV-associated ...epigenetic changes may occur in blood and whether early initiation of antiretroviral therapy (ART) impacts epigenetic modifications. We profiled longitudinal genome-wide DNA methylation in monocytes and CD4+ T lymphocytes from 22 participants in the RV254/SEARCH010 acute HIV infection (AHI) cohort that diagnoses infection within weeks after estimated exposure and immediately initiates ART. We identified monocytes harbored 22,697 differentially methylated CpGs associated with AHI compared to 294 in CD4+ T lymphocytes. ART minimally restored less than 1% of these changes in monocytes and had no effect upon T cells. Monocyte DNA methylation patterns associated with viral load, CD4 count, CD4/CD8 ratio, and longitudinal clinical phenotypes. Our findings suggest HIV-1 rapidly embeds an epigenetic memory not mitigated by ART and support determining epigenetic signatures in precision HIV medicine. Trial Registration: NCT00782808 and NCT00796146.
Early relapse after platinum chemotherapy in epithelial ovarian cancer (EOC) portends poor survival. A‐priori identification of platinum resistance is therefore crucial to improve on standard ...first‐line carboplatin–paclitaxel treatment. The DNA repair pathway homologous recombination (HR) repairs platinum‐induced damage, and the HR recombinase RAD51 is overexpressed in cancer. We therefore designed a REMARK‐compliant study of pre‐treatment RAD51 expression in EOC, using fluorescent quantitative immunohistochemistry (qIHC) to overcome challenges in quantitation of protein expression in situ. In a discovery cohort (n = 284), RAD51‐High tumours had shorter progression‐free and overall survival compared to RAD51‐Low cases in univariate and multivariate analyses. The association of RAD51 with relapse/survival was validated in a carboplatin monotherapy SCOTROC4 clinical trial cohort (n = 264) and was predominantly noted in HR‐proficient cancers (Myriad HRDscore < 42). Interestingly, overexpression of RAD51 modified expression of immune‐regulatory pathways in vitro, while RAD51‐High tumours showed exclusion of cytotoxic T cells in situ. Our findings highlight RAD51 expression as a determinant of platinum resistance and suggest possible roles for therapy to overcome immune exclusion in RAD51‐High EOC. The qIHC approach is generalizable to other proteins with a continuum instead of discrete/bimodal expression.
Synopsis
Quantitative immunohistochemistry (qIHC) reveals that high expression of the DNA repair protein RAD51 in epithelial ovarian cancer is associated with early relapse after platinum chemotherapy, and also with decreased cytotoxic T‐cell infiltration into tumors.
High nuclear expression score for RAD51 (RAD51NES) was correlated with early relapse and shorter survival in two independent EOC patient cohorts (n = 264 + 284).
RAD51NES was prognostically relevant primarily for EOCs that did not have homologous recombination deficiency (HRD).
RAD51 expression was correlated with a unique immune phenotype in cancer, with increased chemokines but reduced cytotoxic T‐cell infiltration.
Quantitative immunohistochemistry (qIHC) reveals that high expression of the DNA repair protein RAD51 in epithelial ovarian cancer (EOC) is associated with early relapse after platinum chemotherapy, and also with decreased cytotoxic T‐cell infiltration into tumors.
Skeletal muscle handles ~80-90% of the insulin-induced glucose uptake. In skeletal muscle, insulin binding to its cell surface receptor triggers redistribution of intracellular glucose transporter ...GLUT4 protein to the cell surface, enabling facilitated glucose uptake. In adipocytes, the eight-protein exocyst complex is an indispensable constituent in insulin-induced glucose uptake, as it is responsible for the targeted trafficking and plasma membrane-delivery of GLUT4. However, the role of the exocyst in skeletal muscle glucose uptake has never been investigated. Here we demonstrate that the exocyst is a necessary factor in insulin-induced glucose uptake in skeletal muscle cells as well. The exocyst complex colocalizes with GLUT4 storage vesicles in L6-GLUT4myc myoblasts at a basal state and associates with these vesicles during their translocation to the plasma membrane after insulin signaling. Moreover, we show that the exocyst inhibitor endosidin-2 and a heterozygous knockout of
in skeletal myoblast cells both lead to impaired GLUT4 trafficking to the plasma membrane and hinder glucose uptake in response to an insulin stimulus. Our research is the first to establish that the exocyst complex regulates insulin-induced GLUT4 exocytosis and glucose metabolism in muscle cells. A deeper knowledge of the role of the exocyst complex in skeletal muscle tissue may help our understanding of insulin resistance in type 2 diabetes.
The motion of cloud over a photovoltaic (PV) power station will directly cause the change of solar irradiance, which indirectly affects the prediction of minute-level PV power. Therefore, the ...calculation of cloud motion speed is very crucial for PV power forecasting. However, due to the influence of complex cloud motion process, it is very difficult to achieve accurate result using a single traditional algorithm. In order to improve the computation accuracy, a pattern classification and particle swarm optimization optimal weights based sky images cloud motion speed calculation method for solar PV power forecasting (PCPOW) is proposed. The method consists of two parts. First, we use a k -means clustering method and texture features based on a gray-level co-occurrence matrix to classify the clouds. Second, for different cloud classes, we build the corresponding combined calculation model to obtain cloud motion speed. Real data recorded at Yunnan Electric Power Research Institute are used for simulation ; the results show that the cloud classification and optimal combination model are effective, and the PCPOW can improve the accuracy of displacement calculation.
This study aimed to identify candidate host epigenetic biomarkers predicting latency reversal agents (LRA) efficacy and HIV-1 rebound kinetics during analytical treatment interruption (ATI).
...Retrospective longitudinal epigenetic profiling study from 13 people with HIV (PWH) on virologically suppressive antiretroviral therapy (ART) that participated in a LRA (HDAC inhibitor) clinical trial (NCT01680094) and a subsequent optional ATI to monitor for viral recrudescence after ART cessation.
Genome-wide DNA methylation (DNAm) in purified CD4+ T cells was measured at single-nucleotide resolution using the Infinium MethylationEPIC array. HIV-1 DNA and RNA measures were previously assessed by PCR-based methods and the association of DNAm levels at regulatory sites of the human genome were examined with reservoir size, responsiveness to LRA, and time to viral rebound following ATI.
A distinct set of 15 candidate DNAm sites in purified CD4+ T cells at baseline pre-LRA and pre-ATI significantly correlated with time to viral rebound. Eight of these DNAm sites occurred in genes linked to HIV-1 replication dynamics including (SEPSECS, cg19113954), (MALT1, cg15968021), (CPT1C, cg14318858), (CRTAM, cg10977115), (B4GALNT4, cg04663285), (IL10, cg16284789), (TFPI2, cg19645693), and (LIFR, cg26437306); with the remaining sites at intergenic regions containing regulatory elements. Moreover, baseline DNAm states related to total HIV-1 DNA levels and the fold change in unspliced cell-associated HIV RNA following LRA treatment.
Preexisting host epigenetic states may determine HIV-1 rebound kinetics and reservoir maintenance. These findings suggest integrating a suite of DNA methylation markers to improve optimal participant selection and drug regimen in future HIV cure clinical trials.
To lower the AC losses in electrical machines, additive manufacturing (AM) has been adopted to exploit the geometrical freedom in winding design. However, AM brings about new challenges such as ...surface roughness and porosity which can create difficulties for post processing of the windings such as applying insulation coatings. The paper investigates the influence of surface roughness (profile) of AM-processed CuCrZr as a potential candidate for electrical windings in terms of geometry, surface roughness, porosity, and oxidation on their insulation. The feasibility and characteristics of insulations applied via three processing techniques namely powder, spray and dip coating are compared. The entire process is quantified via techniques such as computed tomography, surface profilometry, optical microscopy, X-ray photon spectroscopy and breakdown voltage at different stages of the coating process. The study also includes coating on a commercial rectangular copper wire as a reference. The initial assessment of coatings concludes that surface roughness and the coating process are both vital determinants for the success of insulating AM components. Basic surface smoothening is needed to get rid of burs and spray coating technique was the best among others for its capability to produce conformal coating.
Background
COVID‐19 can present with lymphopenia and extraordinary complex multiorgan pathologies that can trigger long‐term sequela.
Aims
Given that inflammasome products, like caspase‐1, play a ...role in the pathophysiology of a number of co‐morbid conditions, we investigated caspases across the spectrum of COVID‐19 disease.
Materials & Methods
We assessed transcriptional states of multiple caspases and using flow cytometry, the expression of active caspase‐1 in blood cells from COVID‐19 patients in acute and convalescent stages of disease. Non‐COVID‐19 subject presenting with various comorbid conditions served as controls.
Results
Single‐cell RNA‐seq data of immune cells from COVID‐19 patients showed a distinct caspase expression pattern in T cells, neutrophils, dendritic cells, and eosinophils compared with controls. Caspase‐1 was upregulated in CD4+ T‐cells from hospitalized COVID‐19 patients compared with unexposed controls. Post‐COVID‐19 patients with lingering symptoms (long‐haulers) also showed upregulated caspase‐1activity in CD4+ T‐cells that ex vivo was attenuated with a select pan‐caspase inhibitor. We observed elevated caspase‐3/7levels in red blood cells from COVID‐19 patients compared with controls that was reduced following caspase inhibition.
Discussion
Our preliminary results suggest an exuberant caspase response in COVID‐19 that may facilitate immune‐related pathological processes leading to severe outcomes. Further clinical correlations of caspase expression in different stages of COVID‐19 will be needed.
Conclusion
Pan‐caspase inhibition could emerge as a therapeutic strategy to ameliorate or prevent severe COVID‐19.
This study assesses transcriptional states of multiple caspases and the expression of active caspase‐1 in blood cells from COVID‐19 patients in acute and convalescent stages of disease. Elevated caspase‐3/7 levels in red blood cells is observed in COVID‐19 patients compared to controls. Post‐COVID‐19 patients with lingering symptoms show up‐regulated caspase‐1 activity in CD4+ T‐cells that is attenuated ex vivo with a select pan‐caspase inhibitor. An exuberant caspase response in COVID‐19 that may facilitate immune‐related pathological processes leading to severe outcomes.
Abbreviations: APC, antigen‐presenting cell; COVID‐19, coronavirus disease 2019; ICU, intensive care unit; PBMC, peripheral blood mononuclear cell; RBC, red blood cell; SARS‐CoV‐2, severe acute respiratory syndrome coronavirus 2
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