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Rechargeable metal-sulfur batteries are considered promising candidates for energy storage due to their high energy density along with high natural abundance and low cost of raw materials. However, they could not yet be practically implemented due to several key challenges: (i) poor conductivity of sulfur and the discharge product metal sulfide, causing sluggish redox kinetics, (ii) polysulfide shuttling, and (iii) parasitic side reactions between the electrolyte and the metal anode. To overcome these obstacles, numerous strategies have been explored, including modifications to the cathode, anode, electrolyte, and binder. In this review, the fundamental principles and challenges of metal-sulfur batteries are first discussed. Second, the latest research on metal-sulfur batteries is presented and discussed, covering their material design, synthesis methods, and electrochemical performances. Third, emerging advanced characterization techniques that reveal the working mechanisms of metal-sulfur batteries are highlighted. Finally, the possible future research directions for the practical applications of metal-sulfur batteries are discussed. This comprehensive review aims to provide experimental strategies and theoretical guidance for designing and understanding the intricacies of metal-sulfur batteries; thus, it can illuminate promising pathways for progressing high-energy-density metal-sulfur battery systems.
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The triple oxygen isotope composition (Δ'17O) of sulfate minerals is widely used to constrain ancient atmospheric pO2/pCO2 and rates of gross primary production. The utility of this tool is based on a model that sulfate oxygen carries an isotope fingerprint of tropospheric O2 incorporated through oxidative weathering of reduced sulfur minerals, particularly pyrite. Work to date has targeted Proterozoic environments (2.5 billion to 0.542 billion years ago) where large isotope anomalies persist; younger timescale records, which would ground ancient environmental interpretation in what we know from modern Earth, are lacking. Here we present a high-resolution record of the [Formula: see text]O and Δ'17O in marine sulfate for the last 130 million years of Earth history. This record carries a Δ'17O close to 0o, suggesting that the marine sulfate reservoir is under strict control by biogeochemical cycling (namely, microbial sulfate reduction), as these reactions follow mass-dependent fractionation. We identify no discernible contribution from atmospheric oxygen on this timescale. We interpret a steady fractional contribution of microbial sulfur cycling (terrestrial and marine) over the last 100 million years, even as global weathering rates are thought to vary considerably.
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Isótopos de Oxigênio , Água do Mar , Sulfatos , Isótopos de Oxigênio/análise , Água do Mar/química , Água do Mar/microbiologia , Sulfatos/química , Óxidos de EnxofreRESUMO
Cytokine release syndrome (CRS) is an acute systemic inflammatory reaction in which hyperactivated immune cells suddenly release a large amount of cytokines, leading to exaggerated inflammatory responses, multiple organ dysfunction, and even death. Although palliative treatment strategies have significantly reduced the overall mortality, novel targeted treatment regimens with superior therapy efficacy are urgently needed. Vascular endothelial cells (ECs) are important target cells of systemic inflammation, and their destruction is considered to be the initiating event underlying many serious complications of CRS. Mesenchymal stem/stromal cells (MSCs) are multipotent cells with self-renewing differentiation capacity and immunomodulatory properties. MSC transplantation can effectively suppress the activation of immune cells, reduce the bulk release of cytokines, and repair damaged tissues and organs. Here, we review the molecular mechanisms underlying CRS-induced vascular endothelial injury and discuss potential treatments using MSCs. Preclinical studies demonstrate that MSC therapy can effectively repair endothelium damage and thus reduce the incidence and severity of ensuing CRS-induced complications. This review highlights the therapeutic role of MSCs in fighting against CRS-induced EC damage, and summarizes the possible therapeutic formulations of MSCs for improved efficacy in future clinical trials.
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BACKGROUND: COVID-19 is a global pandemic. Understanding the immune responses in pregnant women recovering from COVID-19 may suggest new therapeutic approaches. METHODS: We performed a cross-sectional study between March 1, 2020, and September 1, 2020. Participants were assigned into the convalescent COVID-19 group if they had a previous COVID-19 infection during pregnancy or the healthy control group. RNA-Seq was performed on human umbilical cord mesenchymal stem cells (hUMSCs) and human amniotic mesenchymal stem cells (hAMSCs). Immunohistochemical staining, cytokine testing, lymphocyte subset analysis, RNA-Seq, and functional analyses were performed on the placental and umbilical cord blood (UCB) and compared between the two groups. RESULTS: A total of 40 pregnant women were enrolled, with 13 in the convalescent group and 27 in the control group. There were 1024, 46, and 32 differentially expressed genes (DEGs) identified in the placental tissue, hUMSCs, and hAMSCs between the convalescent and control groups, respectively. Enrichment analysis showed those DEGs were associated with immune homeostasis, antiviral activity, cell proliferation, and tissue repair. Levels of IL-6, TNF-α, total lymphocyte counts, B lymphocytes, Tregs percentages, and IFN-γ expressing CD4+ and CD8+ T cells were statistically different between two groups (p ≤ 0.05). ACE2 and TMPRSS2 expressed on the placenta were not different between the two groups (p > 0.05). CONCLUSION: Multiple changes in immune responses occurred in the placental tissue, hUMSCs, and hAMSCs after maternal recovery from COVID-19, which might imply their protective roles against COVID-19 infection.
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COVID-19 , Citocinas , Gravidez , Feminino , Humanos , Linfócitos T CD8-Positivos , Estudos Transversais , Gestantes , Placenta , RNARESUMO
Retinoids may regulate cell differentiation as ligands of retinoic acid receptors (RARs) and/or retinoid X receptors (RXRs). We showed that RAR agonists promoted adipogenesis by upregulating the expression of CCAAT/enhancer-binding protein ß (C/EBPß) in the early stages, but blocked adipogenesis at a later stage in human bone marrow mesenchymal stem cells (hBMSCs). RXR agonists promoted adipogenesis at all time points in hBMSCs. The effect of RAR agonists was mediated mainly by the RARß subtype. RAR agonists, in contrast to RXR agonists, significantly promoted the expression of RARß. Knockdown of the RARß gene via small hairpin RNA (shRNA) attenuated the inhibition of RAR agonists toward adipogenesis. Furthermore, we found that RAR agonists upregulated the transforming growth factor ß (TGFß)/SMAD pathway and Wnt/ß-catenin pathway on adipogenesis in hBMSCs, and the stimulating effects were noticeably decreased with the RARß gene knockdown. Both RAR agonists and RXR agonists inhibited adipogenesis and blocked the promoter activity of C/EBPß and peroxisome proliferator-activated receptor γ (PPARγ) in SW872 cell. These results indicated the RAR agonists perform dual roles in adipogenesis in hBMSCs, and the TGFß/SMAD pathway and Wnt/ß-catenin pathway may involve the inhibitory effect of RAR agonists. RARß is the main receptor subtype mediating the effect. The roles of RXR agonists in adipogenesis exhibited cell type-specific differences, and may be based on the integration of signals from different RXR dimers.
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Adipogenia/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Retinoides/farmacologia , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Via de Sinalização Wnt , Adipogenia/genética , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Células-Tronco Mesenquimais/citologia , PPAR gama/metabolismo , Receptores do Ácido Retinoico/metabolismo , Receptores X de Retinoides/metabolismo , Ativação Transcricional/efeitos dos fármacosRESUMO
TGF-ß is widely existed in tumor microenvironment, taking part in tumorigenesis process including angiogenesis, cancer associated fibroblast (CAF) proliferation, and immunosuppression. It inhibited the activation, proliferation, migration and differentiation of T cells, in which way caused a limited therapeutic effects of chimeric antigen receptor T (CAR-T) towards solid tumor such as lymphoma. To targeted block TGF-ß at tumor site, we take advantages of nano-techniques to deliver TGF-ß inhibitors LY2157299 (LY) towards the tumor sites, in order to help achieve a improved and long-term functions of CAR-T towards lymphoma. Based on amphipathic hydroxyethyl starch-polycaprolactone (HES-PCL), LY and photosensitizer indocyanine green (ICG) were co-loaded in HES-PCL to achieve LY/ICG@HES-PCL nanoparticle. The enhanced function of CAR-T benefited from LY/ICG@HES-PCL were verified through lymphoma Raji cells in vitro and Nod scid gamma mice engrafted with the Raji cells in vivo. LY was targeted transported to tumor site and accelerated release by mild ICG photothermal. Chemokines CXCL9/10/11 âat the tumor site relevant to CAR-T migration and chemokines receptor CXCR3 of CAR-T could be up-regulated by LY, thus facilitated the enhanced accumulation of CAR-T at lymphoma site. T effector memory cells differentiation could also be accelerated by LY/ICG@HES-PCL. Combined therapy of LY/ICG@HES-PCL and CAR-T achieved 2.4 times higher antitumor activity and 2.7 times higher relapse inhibiting rates than CAR-T alone within 15 days and 11 days, respectively. The results suggested that LY/ICG@HES-PCL facilitated the enhanced therapeutic index of CAR-T cells towards lymphoma simply and safely, it may be further potentiated applied for other solid tumors.
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Serpentinization of peridotite provides a significant source of energy for the subseafloor biosphere and abiotic organic synthesis. The presence of diverse micrometer-scale organic matter in serpentinites offers insights into deep carbon cycling and the origin of life on Earth. It is critical to maintain stringent lab protocols in analyzing serpentinite samples, limiting the contact with organic materials that could contaminate serpentinites and cause misinterpretations. However, the extent to which these organic materials (e.g. latex gloves or nylon polishing disc) can introduce contamination remains unclear. Here we subject serpentinite samples from the Yap Trench in the western Pacific Ocean to multi-stage cutting and polishing procedures prior to analysis. Our findings from electron microscopy reveal that micrometer-scale organic matter in serpentinites is randomly distributed either on the sample surface or within Cr-spinel fractures. Further analysis using Raman spectroscopy indicates that the organic matter contains several hydrogen bonding moieties, similar to those found in the latex gloves or nylon polishing disc used during the treatment of serpentinite samples. Our results suggest that the detected organic matter is likely due to contamination from the organic materials involved during sample processing. Thus, future studies need to carefully assess micrometer-scale organic contamination and limit the use of organic materials when analyzing organic compounds hosted in serpentinites, not only on Earth but also on other rocky planets.
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Lithium-sulfur (Li-S) batteries have become one of the most promising new-generation energy storage systems owing to their ultrahigh energy density (2600 Wh kg-1 ), cost-effectiveness, and environmental friendliness. Nevertheless, their practical applications are seriously impeded by the shuttle effect of soluble lithium polysulfides (LiPSs), and the uncontrolled dendrite growth of metallic Li, which result in rapid capacity fading and battery safety problems. A systematic and comprehensive review of the cooperative combination effect and tackling the fundamental problems in terms of cathode and anode synchronously is still lacking. Herein, for the first time, the strategies for inhibiting shuttle behavior and dendrite-free Li-S batteries simultaneously are summarized and classified into three parts, including "two-in-one" S-cathode and Li-anode host materials toward Li-S full cell, "two birds with one stone" modified functional separators, and tailoring electrolyte for stabilizing sulfur and lithium electrodes. This review also emphasizes the fundamental Li-S chemistry mechanism and catalyst principles for improving electrochemical performance; advanced characterization technologies to monitor real-time LiPS evolution are also discussed in detail. The problems, perspectives, and challenges with respect to inhibiting the shuttle effect and dendrite growth issues as well as the practical application of Li-S batteries are also proposed.
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BACKGROUND: Recent studies have shown that mesenchymal stem cell (MSC) therapy has potential therapeutic effects for patients with end-stage liver diseases. However, a consensus on the efficacy and safety of MSCs has not been reached. METHODS: A systemic literature review was conducted by searching the Cochrane Library and PubMed databases for articles that evaluated the impact of MSC therapy on the outcomes among patients with end-stage liver disease. Various parameters, including pre- and post-treatment model of end-stage liver disease (MELD) score, serum albumin (ALB), total bilirubin (TB), coagulation function, aminotransferase, and survival rate, were evaluated. RESULTS: This meta-analysis included a final total of 13 studies and 854 patients. The results indicated improved liver parameters following MSC therapy at different time points, including in terms of MELD score, TB level, and ALB level, compared with conventional treatment. Furthermore, the MSC treatment increased the overall survival rate among patients with liver cirrhosis and acute-on-chronic liver failure (ACLF). The changes in transaminase level and coagulation function differed between the different therapies at various post-treatment time points, indicating that MSC therapy provided no significant benefits in this regard. The further subgroup analysis stratified by liver background revealed that patients with ACLF benefit more from MSC therapy at most time points with improved liver function, including in terms of MELD score, TB level, and ALB level. In addition, no serious side effects or adverse events were reported following MSC therapy. CONCLUSIONS: The meta-analysis results suggest that MSC therapy is safe and results in improved liver function and survival rates among patients with end-stage liver disease. The subgroup analysis stratified by liver background indicated that patients with ACLF benefit more from MSC therapy than patients with liver cirrhosis at most time points.
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Insuficiência Hepática Crônica Agudizada , Doença Hepática Terminal , Células-Tronco Mesenquimais , Humanos , Insuficiência Hepática Crônica Agudizada/terapia , Medula Óssea , Cirrose Hepática/terapiaRESUMO
BACKGROUND: The objective of this study was to identify potential biomarkers for predicting response to MSC therapy by pre-MSC treatment plasma proteomic profile in severe COVID-19 in order to optimize treatment choice. METHODS: A total of 58 patients selected from our previous RCT cohort were enrolled in this study. MSC responders (n = 35) were defined as whose resolution of lung consolidation ≥ 51.99% (the median value for resolution of lung consolidation) from pre-MSC to 28 days post-MSC treatment, while non-responders (n = 23) were defined as whose resolution of lung consolidation < 51.99%. Plasma before MSC treatment was detected using data-independent acquisition (DIA) proteomics. Multivariate logistic regression analysis was used to identify pre-MSC treatment plasma proteomic biomarkers that might distinguish between responders and non-responders to MSC therapy. RESULTS: In total, 1101 proteins were identified in plasma. Compared with the non-responders, the responders had three upregulated proteins (CSPG2, CTRB1, and OSCAR) and 10 downregulated proteins (ANXA1, AGRG6, CAPG, DDX55, KV133, LEG10, OXSR1, PICAL, PTGDS, and S100A8) in plasma before MSC treatment. Using logistic regression model, lower levels of DDX55, AGRG6, PICAL, and ANXA1 and higher levels of CTRB1 pre-MSC treatment were predictors of responders to MSC therapy, with AUC of the ROC at 0.910 (95% CI 0.818-1.000) in the training set. In the validation set, AUC of the ROC was 0.767 (95% CI 0.459-1.000). CONCLUSIONS: The responsiveness to MSC therapy appears to depend on baseline level of DDX55, AGRG6, PICAL, CTRB1, and ANXA1. Clinicians should take these factors into consideration when making decision to initiate MSC therapy in patients with severe COVID-19.
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COVID-19 , Transplante de Células-Tronco Mesenquimais , Humanos , COVID-19/terapia , Proteômica , Biomarcadores/metabolismo , Proteínas Serina-Treonina QuinasesRESUMO
Atmospheric deposition of particulate organic nitrogen (ONp) is a significant process in the global nitrogen cycle and may be pivotally important for N-limited ecosystems. However, past models largely overlooked the spatial and chemical inhomogeneity of atmospheric ONp and were thus deficient in assessing global ONp impacts. We constructed a comprehensive global model of atmospheric gaseous and particulate organic nitrogen (ON), including the latest knowledge on emissions and secondary formations. Using this model, we simulated global atmospheric ONp abundances consistent with observations. Our estimated global atmospheric ON deposition was 26 Tg N yr-1, predominantly in the form of ONp (23 Tg N yr-1) and mostly from wildfires (37%), oceans (22%) and aqueous productions (17%). Globally, ONp contributed as much as 40% to 80% of the total N deposition downwind of biomass-burning regions. Atmospheric ONp deposition thus constituted the dominant external N supply to the N-limited boreal forests, tundras and the Arctic Ocean, and its importance may be amplified in a future warming climate.
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BACKGROUND: Long-term effects of human mesenchymal stem cell (MSC) treatment on COVID-19 patients have not been fully characterized. The aim of this study was to evaluate the safety and efficacy of a MSC treatment administered to severe COVID-19 patients enrolled in our previous randomized, double-blind, placebo-controlled clinical trial (NCT04288102). METHODS: A total of 100 patients experiencing severe COVID-19 received either MSC treatment (n = 65, 4 × 107 cells per infusion) or a placebo (n = 35) combined with standard of care on days 0, 3, and 6. Patients were subsequently evaluated 18 and 24 months after treatment to evaluate the long-term safety and efficacy of the MSC treatment. Outcomes measured included: 6-min walking distance (6-MWD), lung imaging, quality of life according to the Short Form 36 questionnaire (SF-36), COVID-19-related symptoms, titers of SARS-CoV-2 neutralizing antibodies, tumor markers, and MSC-related adverse events (AEs). FINDINGS: Two years after treatment, a marginally smaller proportion of patients had a 6-MWD below the lower limit of the normal range in the MSC group than in the placebo group (OR = 0.19, 95% CI: 0.04-0.80, Fisher's exact test, p = 0.015). At month 18, the general health score from the SF-36 was higher in the MSC group than in the placebo group (50.00 vs. 35.00, 95% CI: 0.00-20.00, Wilcoxon rank sum test, p = 0.018). Total severity score of lung imaging and the titer of neutralizing antibodies were similar between the two groups at months 18 and 24. There was no difference in AEs or tumor markers at the 2-year follow-up between the two groups. INTERPRETATION: Long-term safety was observed for the COVID-19 patients who received MSC treatment. However, efficacy of MSC treatment was not significantly sustained through the end of the 2-year follow-up period. FUNDING: The National Key Research and Development Program of China (2022YFA1105604, 2020YFC0860900, 2022YFC2304401), the specific research fund of The Innovation Platform for Academicians of Hainan Province (YSPTZX202216) and the Fund of National Clinical Center for Infectious Diseases, PLA General Hospital (NCRC-ID202105,413FZT6).
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COVID-19 , Transplante de Células-Tronco Mesenquimais , Humanos , COVID-19/terapia , SARS-CoV-2 , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Transplante de Células-Tronco Mesenquimais/métodos , Seguimentos , Qualidade de Vida , Método Duplo-Cego , Resultado do TratamentoRESUMO
This study aimed to study the association between rs12976445 polymorphism and the incidence of IA re-bleeding. Genotype and allele frequency analysis was performed to study the association between rs12976445 polymorphism and the risk of IA re-bleeding. Western blot, ELISA and real-time RT-PCR were conducted to measure the relative expression of miR-125a, ET1 mRNA and ET1 protein. Computational analysis and luciferase assays were utilized to investigate the association between the expression of miR-125a and ET1 mRNA. No significant differences were observed between IA patients with or without symptoms of re-bleeding. Subsequent analyses indicated that the T allele was significantly associated with the reduced risk of IA re-bleeding. In patients carrying the CC genotype, miR-125a level was up-regulated while ET1 mRNA/protein levels were reduced compared with those in patients carrying the CT or TT genotype. And ET1 mRNA was identified as a virtual target gene of miR-125a with a potential miR-125a binding site located on its 3'UTR. Accordingly, the ET mRNA/protein levels could be suppressed by the transfection of miR-125a precursors, but the transfection of ET1 siRNA exhibited no effect on the expression of miR-125a. Therefore, an increased level of miR-125a can lead to the increased risk of IA re-bleeding. Since miR-125a level is higher in CC-genotyped patients, it can be concluded that the presence of T allele in the rs12976445 polymorphism is associated with a lower risk of IA re-bleeding, and miR-125a may be used as a novel diagnostic and therapeutic target for IA rupture.
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Endotelina-1/genética , Predisposição Genética para Doença/genética , Aneurisma Intracraniano/genética , MicroRNAs/genética , Hemorragia Subaracnóidea/patologia , Regiões 3' não Traduzidas/genética , Antifibrinolíticos/uso terapêutico , Encéfalo/irrigação sanguínea , Linhagem Celular , Artérias Cerebrais/patologia , Endotelina-1/biossíntese , Feminino , Frequência do Gene/genética , Estudos de Associação Genética , Humanos , Aneurisma Intracraniano/tratamento farmacológico , Aneurisma Intracraniano/patologia , Masculino , MicroRNAs/biossíntese , Polimorfismo de Nucleotídeo Único/genética , Risco , Hemorragia Subaracnóidea/genéticaRESUMO
Background: The present study aims to better understand the efficacy and safety of mesenchymal stromal cells (MSCs) in treating severe/critical patients with COVID-19. Methods: PubMed, the Cochrane Library, and the Chinese electronic database CNKI were searched from inception up to Dec 19, 2021. Original comparative studies for MSC treatment + standard treatment for severe/critical patients with COVID-19, with placebo or standard treatment as the control group, were included. The primary outcomes were in-hospital mortality and adverse events (AEs). A meta-analysis was performed to compare the mortality rates between the two groups. Then, a subgroup analysis was performed according to the category of the disease (severe or critical) and MSC dose. Afterwards, a descriptive analysis was performed for AEs and secondary outcomes. The funnel plot and Egger's test were used for the publication bias assessment. Findings: Compared to placebo or standard care, MSCs provide significant benefit in the treatment of patients with severe/critical COVID-19, in terms of in-hospital mortality rate (odds ratio: 0.52, 95% CI 0.32-0.84), with very low heterogeneity (P=0.998 [Q test], I 2=0.0%) and less AEs. No significant difference was found in mortality rate due to the different disease categories or MSC doses. Furthermore, no publication bias was found. Interpretation: The present study demonstrates that MSCs are highly likely to reduce mortality and are safe to use for patients with severe or critical COVID-19, regardless of whether 1-3 doses are applied. However, due to the small sample size of the included studies, further high-quality, large-scale trials are needed to confirm this statement in the future. Funding: The National Key Research and Development Program of China (No. 2020YFC0860900), the Science and Technology Project of Wuhan (No. 2020020602012112), the Tianjin Science and Technology Research Program (18PTSYJC00070 and 16PTWYHZ00030), Haihe Laboratory of Cell Ecosystem Innovation Fund (HH22KYZX0046), and the Tianjin Free Trade Zone Innovation Development Project (ZMCY-03-2021002-01) funded the study. We are also grateful for the support from the 3551 Talent Plan of China Optics Valley.
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The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread into more than 200 countries and infected approximately 203 million people globally. COVID-19 is associated with high mortality and morbidity in some patients, and this disease still does not have effective treatments with reproducibly appreciable outcomes. One of the leading complications associated with COVID-19 is acute respiratory distress syndrome (ARDS); this is an anti-viral host inflammatory response, and it is usually caused by a cytokine storm syndrome which may lead to multi-organ failure and death. Currently, COVID-19 patients are treated with approaches that mostly fall into two major categories: immunomodulators, which promote the body's fight against viruses efficiently, and antivirals, which slow or stop viruses from multiplying. These treatments include a variety of novel therapies that are currently being tested in clinical trials, including serum, IL-6 antibody, and remdesivir; however, the outcomes of these therapies are not consistently appreciable and remain a subject of debate. Mesenchymal stem/stromal cells (MSCs), the multipotent stem cells that have previously been used to treat viral infections and various respiratory diseases such as ARDS exhibit immunomodulatory properties and can ameliorate tissue damage. Given that SARS-CoV-2 targets the immune system and causes tissue damage, it is presumable that MSCs are being explored to treat COVID-19 patients. This review summarizes the potential mechanisms of action of MSC therapy, progress of MSC, and its related products in clinical trials for COVID-19 therapy based on the outcomes of these clinical studies.
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COVID-19 , Células-Tronco Mesenquimais , Pneumonia , Síndrome do Desconforto Respiratório , COVID-19/terapia , Humanos , Células-Tronco Mesenquimais/metabolismo , SARS-CoV-2RESUMO
Quantitative determination of sarcosine (SAR) in biological liquids is of great importance, as SAR has been recently suggested as a promising biomarker for prostate cancer diagnostics. Herein, a self-powered photoelectrochemical (PEC) molecular imprinted sensor integrated with photoanode (Au@TiO2 nanorods) and photocathode (Cu2O) is proposed for the first time towards the specific and sensitive detection of SAR. With the benefits of strong photocurrent driving force attributed to a large inherent deviation between the Fermi levels of photoanode and photocathode in this system, the photogenerated electrons of Au@TiO2 can rapidly transferred along the outer circuit and attracted by the holes in the valence band of the photocathode, forming a self-powered PEC system and improve the photocurrent of the cathode. Under the optimal conditions, the constructed cathode imprinted sensor has a linear range of 10 nM - 10 µM, and the limitation of detection is 0.19 nM. This work proved that the PEC sensing platform has great potential in the field of miniaturized biosensing without external power supply.
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Técnicas Biossensoriais , Impressão Molecular , Nanotubos , Técnicas Eletroquímicas , Eletrodos , Humanos , Masculino , Sarcosina , TitânioRESUMO
Chronic liver diseases have become a significant health issue worldwide and urgently require the development of novel therapeutic approaches, in addition to liver transplantation. Recent clinical and preclinical studies have shown that cell-based therapeutic strategies may contribute to the improvement of chronic liver diseases and offer new therapeutic options to restore liver function through their roles in tissue impairment and immunomodulation. In this review, we summarize the current progress and analyze the challenges for different types of cell therapies used in the treatment of chronic liver diseases currently explored in clinical trials and preclinical studies in animal models. We also discuss some critical issues regarding the use of mesenchymal stem cells (MSCs, the most extensive cell source of stem cells), including therapeutic dosage, transfusion routine, and pharmacokinetics/pharmacodynamics (PK/PD) of transfused MSCs.
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Hepatopatias , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Animais , Terapia Baseada em Transplante de Células e Tecidos , Imunomodulação , Hepatopatias/metabolismo , Hepatopatias/terapia , Células-Tronco Mesenquimais/metabolismoRESUMO
Lithium-sulfur (Li-S) batteries have been hindered by the shuttle effect and sluggish polysulfide conversion kinetics. Here, a P-doped nickel tellurium electrocatalyst with Te-vacancies (PâNiTe2- x ) anchored on maize-straw carbon (MSC) nanosheets, served as a functional layer (MSC/PâNiTe2- x ) on the separator of high-performance Li-S batteries. The PâNiTe2- x electrocatalyst enhanced the intrinsic conductivity, strengthened the chemical affinity for polysulfides, and accelerated sulfur redox conversion. The MSC nanosheets enabled NiTe2 nanoparticle dispersion and Li+ diffusion. In situ Raman and ex situ X-ray absorption spectra confirmed that the MSC/PâNiTe2- x restrained the shuttle effect and accelerated the redox conversion. The MSC/PâNiTe2- x -based cell has a cyclability of 637 mAh g-1 at 4 C over 1800 cycles with a degradation rate of 0.0139% per cycle, high rate performance of 726 mAh g-1 at 6 C, and a high areal capacity of 8.47 mAh cm-2 under a sulfur configuration of 10.2 mg cm-2 , and a low electrolyte/sulfur usage ratio of 3.9. This work demonstrates that vacancy-induced doping of heterogeneous atoms enables durable sulfur electrochemistry and can impact future electrocatalytic designs related to various energy-storage applications.
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BACKGROUND: Mesenchymal stem cells (MSC)-based tissue engineered breast represent the visible future for breast reconstruction after mastectomy. However, autologous MSCs might not be appropriate for the large graft construction due to cell senescence during excessive cell expansion, thus hindering its further off-the-shelf application. The human umbilical cord mesenchymal stem cells (hUCMSCs) have been found to induce low immune response and can be easily stored, making them ideal for off-the-shelf tissue engineering application. Here, we explored the feasibility of using umbilical cord mesenchymal stem cells as tissue-engineered breast seed cells. METHODS: The allogenic hUCMSCs were injected into transplanted fat tissue with or without breast scaffolds as an alternative for breast tissue engineering in vivo, and its potential mechanism of angiogenesis in vitro was explored. RESULTS: Transplantation of hUCMSCs promoted proliferation, migration, and angiogenesis of human umbilical vein endothelial cells (HUVECs) through paracrine mechanism by activating the integrin ß1/ERK1/2/HIF-1α/VEGF-A signaling pathway. Histological examination of grafted fat revealed that the group which received hUCMSCs transplantation had more fat tissue [(93.60 ± 2.40) %] and fewer MAC2+CD206- M1 macrophages [(0.50 ± 0.47) cells/field] compared to the control group [fat tissue (45.42 ± 5.96) and macrophage cells/field (5.00 ± 2.23)]. Moreover, the hUCMSCs- labeled with a tracing dye differentiated into adipocytes and vascular endothelial cells in the adipose tissue. When applied to the tissue-engineered breast with a scaffold, the group treated with hUCMSCs had more adipose tissues and CD31+ cells than the control group. CONCLUSIONS: These results demonstrate that allogeneic hUCMSCs promote the regeneration of adipose tissue and can be used to construct a tissue engineered breast.