ABSTRACT
Transcriptional regulation of inducible nitric oxide synthase (iNOS) is critically involved in the pathogenesis and progression of rheumatoid arthritis (RA); however, the specific ...transcription factors that control this process remain largely unidentified. In the present study, it was discovered that expression of the key erythroid factor, globin transcription factor 1 (GATA1), is significantly greater in human RA synovial tissues than in osteoarthritis (OA) tissues. IL 6 was found to induce synovial GATA1 expression in a signal transducer and activator of transcription 3‐dependent manner. Functionally, knockdown of GATA1 expression using specific small interfering RNA treatment was found to compromise immunoreaction‐elicited expression of proinflammatory cytokines and thus impair invasiveness of the human fibroblast‐like synovial cell line MH7A, whereas introduction of exogenous GATA1 was found to promote production of proinflammatory cytokines, leading to greater aggressiveness of MH7A cells. Mechanistically, GATA1 acts as the transcriptional coactivator of NOS2 (the gene encoding iNOS) transcription. Collectively, these data suggest that synovial GATA1 is an essential contributor to development and exacerbation of RA, presumably by inducing NOS2 transcription.
Electrochemical reduction of N2 to NH3 is a promising method for artificial N2 fixation, but it requires efficient and robust electrocatalysts to boost the N2 reduction reaction (NRR). Herein, a ...combination of experimental measurements and theoretical calculations revealed that a hybrid material in which ZnO quantum dots (QDs) are supported on reduced graphene oxide (ZnO/RGO) is a highly active and stable catalyst for NRR under ambient conditions. Experimentally, ZnO/RGO was confirmed to favor N2 adsorption due to the largely exposed active sites of ultrafine ZnO QDs. DFT calculations disclosed that the electronic coupling of ZnO with RGO resulted in a considerably reduced activation‐energy barrier for stabilization of *N2H, which is the rate‐limiting step of the NRR. Consequently, ZnO/RGO delivered an NH3 yield of 17.7 μg h−1 mg−1 and a Faradaic efficiency of 6.4 % in 0.1 m Na2SO4 at −0.65 V (vs. RHE), which compare favorably to those of most of the reported NRR catalysts and thus demonstrate the feasibility of ZnO/RGO for electrocatalytic N2 fixation.
ZnO/RGO can fix it: A hybrid material, in which ZnO quantum dots are supported on reduced graphene oxide (ZnO/RGO), was synthesized by a facile, one‐step, microwave‐assisted solvothermal method and found to be a highly active and stable catalyst for the electrochemical reduction of dinitrogen to ammonia (see figure) under ambient conditions, which is a promising method for artificial nitrogen fixation.
Telomeres with G-rich repetitive DNA and particular proteins as special heterochromatin structures at the termini of eukaryotic chromosomes are tightly maintained to safeguard genetic integrity and ...functionality. Telomerase as a specialized reverse transcriptase uses its intrinsic RNA template to lengthen telomeric G-rich strand in yeast and human cells. Cells sense telomere length shortening and respond with cell cycle arrest at a certain size of telomeres referring to the "Hayflick limit." In addition to regulating the cell replicative senescence, telomere biology plays a fundamental role in regulating the chronological post-mitotic cell ageing. In this review, we summarize the current understandings of telomere regulation of cell replicative and chronological ageing in the pioneer model system
and provide an overview on telomere regulation of animal lifespans. We focus on the mechanisms of survivals by telomere elongation, DNA damage response and environmental factors in the absence of telomerase maintenance of telomeres in the yeast and mammals.
This paper is concerned with the coordinative control problem of networked nonlinear multi-agents (NNM) with communication delays. A high-order fully actuated (HOFA) model is introduced to describe ...the nonlinear multi-agents. Based on this model, a HOFA predictive coordination method is proposed to compensate for the communication delays actively and achieve simultaneous stability and consensus. This method largely simplifies the design of networked nonlinear multi-agents and makes the control performance be same for networked nonlinear multi-agents with and without communication delays. The analysis on the closed-loop systems derives the simultaneous stability and consensus criteria of networked nonlinear multi-agents using the HOFA predictive coordination method. With the presented way of designing HOFA predictive coordination controllers, a simulated example demonstrates the advantages of the proposed method.
•There existed high proportions of COVID-19 patients with psychological problems such as anxiety, depression, post-traumatic stress disorder(PTSD), insomnia, somatization, fear.•The psychological ...problems of the patients varied in different investigation periods and different course stages, which was closely related to the patients themselves, their surroundings and social support.•The prevalence of anxiety, depression and insomnia in severe patients was higher than other patients.•The prevalence of PTSD in COVID-19 patients surveyed from mid-February to mid-March 2021 was higher than other periods.
We aimed to investigate the psychological problems on people infected with SARS-CoV-2 during the pandemic.
In this living systematic review and meta-analyses, we searched seven electronic databases for cross-sectional studies and longitudinal studies on psychological problems on COVID-19 patients from Jan 1, 2020 to Oct 7, 2020. The primary outcome was prevalence of various psychological problems such as anxiety, depression, stress, insomnia, somatization, and fear. We pooled data for prevalence with their 95% confidence interval (CI) using random effect models and assessed the study quality based on the 11-item checklist recommended by the Agency for Healthcare Research and Quality.
Fourty-four studies, including studies from China(35), Italy(2), Iran(2), India(1), Korea(1), Ecuador(1), Switzerland(1), Germany(1), were identified by comprising a total of 8587 completed questionnaires and 38 studies for meta-analyses. The prevalence of anxiety, depression, post-traumatic stress disorder(PTSD), insomnia, somatization, and fear in patients with COVID-19 was 16.6% (10.1%-23.1%), 37.7% (29.3%-46.2%), 41.5% (9.3%-73.7%), 68.3% (48.6%-88.0%), 36.5% (20.2%-52.8%), 47.6% (9.4%-85.7%), respectively. The prevalence of anxiety, depression, and insomnia in severe COVID-19 patients (intensive care unit inpatients) was higher than mild or clinically stable COVID-19 patients.
A significant degree of heterogeneity in terms of populations, sampling methods, scales was noted across studies.
There existed high proportions of COVID-19 patients with psychological problem. The prevalence of psychological problems was closely related to the patients themselves, their surroundings and social support. It is imperative to provide ontime psychological care service for COVID-19 patients and to follow-up them for a longer period.
Considerable evidence suggests that during the progression of complex diseases, the deteriorations are not necessarily smooth but are abrupt, and may cause a critical transition from one state to ...another at a tipping point. Here, we develop a model-free method to detect early-warning signals of such critical transitions, even with only a small number of samples. Specifically, we theoretically derive an index based on a dynamical network biomarker (DNB) that serves as a general early-warning signal indicating an imminent bifurcation or sudden deterioration before the critical transition occurs. Based on theoretical analyses, we show that predicting a sudden transition from small samples is achievable provided that there are a large number of measurements for each sample, e.g., high-throughput data. We employ microarray data of three diseases to demonstrate the effectiveness of our method. The relevance of DNBs with the diseases was also validated by related experimental data and functional analysis.
COVID-19 is an extremely severe infectious disease. However, few studies have focused on the epidemiological and clinical characteristics of pediatric COVID-19. This study conducted a retrospective ...review of the epidemiological and clinical features of COVID-19 in children.
A retrospective study was conducted on children with a definite diagnosis of COVID-19 in mainland China using the web crawler technique to collect anonymous COVID-19 updates published by local health authorities.
Three hundred forty-one children aged 4 days to 14 years with a median age of 7 years were included. Sixty-six percent of pediatric patients were infected via family members with COVID-19. The median incubation period was 9 days (interquartile range, 6 to 13). Asymptomatic cases accounted for 5.9%, of which 30% had abnormal chest radiologic findings. A majority of pediatric COVID-19 cases showed mild to moderate clinical features, and only a few developed severe or critical diseases (0.6% and 0.3%, respectively). Fever (77.9%) and cough (32.4%) were the predominant presenting symptoms of pediatric COVID-19. The pediatric patients had fewer underlying diseases and complications than adults. The treatment modalities for pediatric COVID-19 patients were not as complex as those of adult COVID-19 patients. The overall prognosis of pediatric COVID-19 was benign with a decent recovery. The median time from onset to cure was 16 days (interquartile range, 13 to 21).
Compared to adults, COVID-19 in children has distinct features of epidemiology and clinical manifestations. The findings from this study might help to guide the development of measures to prevent and treat this ongoing global pandemic.
Chinese Clinical Trial Registry ( chictr.org.cn ) identifier: ChiCTR2000030464.
This study employs the free-weighting matrix approach to investigate the output feedback control of a linear discrete-time system with an interval time-varying delay. First, the delay-dependent ...stability is analyzed using a new method of estimating the upper bound on the difference of a Lyapunov function without ignoring any terms; and based on the results, a design criterion for a static output feedback (SOF) controller is derived. Since the conditions thus obtained for the existence of admissible controllers are not expressed strictly in terms of linear matrix inequalities, a modified cone complementarity linearization algorithm is employed to solve the nonconvex feasibility SOF control problem. Furthermore, the problem of designing a dynamic output feedback controller is formulated as one of designing an SOF controller. Numerical examples demonstrate the effectiveness of the method and its advantage over existing methods.
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