Navigating the future of retinitis pigmentosa treatments: A comprehensive analysis of therapeutic approaches in rd10 mice.

Retinitis pigmentosa (RP) is a degenerative disease, caused by genetic mutations that lead to a loss in photoreceptors. For research on RP, rd10 mice, which carry mutations in the phosphodiesterase (PDE) gene, exhibit degenerative patterns comparable to those of patients with RP, making them an ideal model for investigating potential treatments. Although numerous studies have reported the potential of biochemical drugs, gene correction, and stem cell transplantation in decelerating rd10 retinal degeneration, a comprehensive review of these studies has yet to be conducted. Therefore, here, a comparative analysis of rd10 mouse treatment research over the past decade was performed. Our findings suggest that biochemical drugs capable of inhibiting the inflammatory response may be promising therapeutics. Additionally, significant progress has been made in the field of gene therapy; nevertheless, challenges such as strict delivery requirements, bystander editing, and off-target effects still need to be resolved. Nevertheless, secretory function is the only unequivocal protective effect of stem cell transplantation. In summary, this review presents a comprehensive analysis and synthesis of the treatment approaches employing rd10 mice as experimental subjects, describing a clear pathway for future RP treatment research and identifies potential clinical interventions.

The role of Interleukin-22 in severe acute pancreatitis.

Severe acute pancreatitis (SAP) begins with premature activation of enzymes, promoted by the immune system, triggering a potential systemic inflammatory response that leads to organ failure with increased mortality and a bleak prognosis. Interleukin-22 (IL-22) is a cytokine that may have a significant role in SAP. IL-22, a member of the IL-10 cytokine family, has garnered growing interest owing to its potential tissue-protective properties. Recently, emerging research has revealed its specific effects on pancreatic diseases, particularly SAP. This paper provides a review of the latest knowledge on the role of IL-22 and its viability as a therapeutic target in SAP.

Study on the Rectification of Ionic Diode Based on Cross-Linked Nanocellulose Bipolar Membranes.

Nanocellulose-based membranes have attracted intense attention in bioelectronic devices due to their low cost, flexibility, biocompatibility, degradability, and sustainability. Herein, we demonstrate a flexible ionic diode using a cross-linked bipolar membrane fabricated from positively and negatively charged cellulose nanofibrils (CNFs). The rectified current originates from the asymmetric charge distribution, which can selectively determine the direction of ion transport inside the bipolar membrane. The mechanism of rectification was demonstrated by electrochemical impedance spectroscopy with voltage biases. The rectifying behavior of this kind of ionic diode was studied by using linear sweep voltammetry to obtain current-voltage characteristics and the time dependence of the current. In addition, the performance of cross-linked CNF diodes was investigated while changing parameters such as the thickness of the bipolar membranes, the scanning voltage range, and the scanning rate. A good long-term stability due to the high density cross-linking of the diode was shown in both current-voltage characteristics and the time dependence of current.

Combined application of myo-inositol and corn steep liquor enhances seedling growth and cold tolerance in cucumber and tomato.

Low temperatures pose a common challenge in the production of cucumbers and tomatoes, hindering plant growth and, in severe cases, leading to plant death. In our investigation, we observed a substantial improvement in the growth of cucumber and tomato seedlings through the application of corn steep liquor (CSL), myo-inositol (MI), and their combinations. When subjected to low-temperature stress, these treatments resulted in heightened levels of photosynthetic pigments, thereby fostering enhanced photosynthesis in both tomato and cucumber plants. Furthermore, it contributed to a decrease in malondialdehyde (MDA) levels and electrolyte leakage (REP). The effectiveness of the treatment was further validated through the analysis of key gene expressions (CBF1, COR, MIOX4, and MIPS1) in cucumber. Particularly, noteworthy positive outcomes were noted in the treatment involving 0.6 mL L-1 CSL combined with 72 mg L-1 MI. This study provides valuable technical insights into leveraging the synergistic effects of inositol and maize leachate to promote early crop growth and bolster resistance to low temperatures.

CRISPR/Cas9-mediated editing of GmDWF1 brassinosteroid biosynthetic gene induces dwarfism in soybean.

KEY MESSAGE: The study on the GmDWF1-deficient mutant dwf1 showed that GmDWF1 plays a crucial role in determining soybean plant height and yield by influencing the biosynthesis of brassinosteroids. Soybean has not adopted the Green Revolution, such as reduced height for increased planting density, which have proven beneficial for cereal crops. Our research identified the soybean genes GmDWF1a and GmDWF1b, homologous to Arabidopsis AtDWF1, and found that they are widely expressed, especially in leaves, and linked to the cellular transport system, predominantly within the endoplasmic reticulum and intracellular vesicles. These genes are essential for the synthesis of brassinosteroids (BR). Single mutants of GmDWF1a and GmDWF1b, as well as double mutants of both genes generated through CRISPR/Cas9 genome editing, exhibit a dwarf phenotype. The single-gene mutant exhibits moderate dwarfism, while the double mutant shows more pronounced dwarfism. Despite the reduced stature, all types of mutants preserve their node count. Notably, field tests have shown that the single GmDWF1a mutant produced significantly more pods than wild-type plants. Spraying exogenous brassinolide (BL) can compensate for the loss in plant height induced by the decrease in endogenous BRs. Comparing transcriptome analyses of the GmDWF1a mutant and wild-type plants revealed a significant impact on the expression of many genes that influence soybean growth. Identifying the GmDWF1a and GmDWF1b genes could aid in the development of compact, densely planted soybean varieties, potentially boosting productivity.

Microwave-Assisted Synthesis of Highly Active Single-Atom Fe/N/C Catalysts for High-Performance Aqueous and Flexible All-Solid-State Zn-Air Batteries.

The development of low-cost single-atom electrocatalysts for oxygen reduction reaction (ORR) is highly desired but remains a grand challenge. Superior to the conventional techniques, a microwave-assisted strategy is reported for rapid production of high-quality Fe/N/C single-atom catalysts (SACs) with profoundly enhanced reaction rate and remarkably reduced energy consumption. The as-synthesized catalysts exhibit an excellent ORR performance with a positive half-wave potential up to 0.90 V, a high turnover frequency of 0.76 s-1 , as well as a satisfied stability with a lost half-wave potential of just 27 mV over 9000 cycles (much better than that of Pt/C with 107 mV lost) and good methanol resistance. The open-circuit voltages of as-constructed aqueous and flexible all-solid-state Zn-air batteries (ZABs) are 1.56 and 1.52 V, respectively, higher than those of 20% Pt/C-based ones (i.e., 1.43 and 1.38 V, respectively). Impressively, they afford a peak power density of 235 mW cm-2 , which exceeds that of Pt/C (i.e., 186 mW cm-2 ), and is comparable to the best ones of Fe/N/C-based ZABs ever reported.

Achieving enhanced sensitivity and accuracy in carcinoembryonic antigen (CEA) detection as an indicator of cancer monitoring using thionine/chitosan/graphene oxide nanocomposite-modified electrochemical immunosensor.

The current study has focused on electrochemical immunosensing of carcinoembryonic antigen (CEA) employing an immobilized antibody on a thionine, chitosan, or graphene oxide nanocomposite modified glassy carbon electrode (anti-CEA/THi-CS-GO/GCE) as an indicator of cancer monitoring. THi-CS-GO nanocomposites were made using ultrasonication, and analyses of their morphology and crystal structure using SEM, FTIR, and XRD showed that thionine and chitosan molecules were intercalated with stacking interactions with both the top and bottom of GO nanosheets. Electrochemical experiments revealed anti-CEA, THi-CS-GO/GCE to have exceptional sensitivity and selectivity towards CEA compounds. The detection limit value was established to be 0.8 pg/mL when it was discovered that variations in the decrease peak current were directly proportional to the logarithm concentration of CEA over a wide range from 10-3 to 104 ng/mL. Results of testing the immunosensor's application capability for detecting CEA in a sample of human serum show that ELISA and DPV results are very congruent. The produced immunosensor demonstrated adequate immunosensor precision in determining CEA in prepared genuine samples of human serum and clinical applications.

Exploring mechanical properties and failure mechanisms of aramid and PBO crystals through molecular dynamics simulations.

Molecular dynamics simulations were used to analyze the mechanical properties and failure processes of poly(p-phenylene-terephthalamide) (PPTA), poly(p-phenylene-benzimidazole-terephthalamide) (PBIA), PBIA-PPTA (formed by 1:1 copolymerization of PPTA and PBIA), and poly(p-phenylene-benzobisoxazole) (PBO) crystals at different strain rates and temperatures. The failure stress and strain were found to be linear with the temperature and logarithmic strain rate. Moreover, based on the kinetic theory of fracture and the comprehensive simulation results, we formulated a model that describes the failure stress of the aforementioned crystals under varying strain rates and temperatures. Through the analysis of the failure process, we found that in PPTA, PBIA, and PBIA-PPTA crystals, the bond failure probability is correlated with the strain rate and temperature. The examination of bond lengths and angles unveiled that bonds with larger initial aligning angles are more susceptible to failure during the strain process. Intriguingly, the stretching process induced a conformational change in the PBO molecular chain, leading to a deviation from the linear relation in its stress-strain curve.

RNA-Seq and Comparative Transcriptomic Analyses of Asian Soybean Rust Resistant and Susceptible Soybean Genotypes Provide Insights into Identifying Disease Resistance Genes.

Asian soybean rust (ASR), caused by Phakopsora pachyrhizi, is one of the most destructive foliar diseases that affect soybeans. Developing resistant cultivars is the most cost-effective, environmentally friendly, and easy strategy for controlling the disease. However, the current understanding of the mechanisms underlying soybean resistance to P. pachyrhizi remains limited, which poses a significant challenge in devising effective control strategies. In this study, comparative transcriptomic profiling using one resistant genotype and one susceptible genotype was performed under infected and control conditions to understand the regulatory network operating between soybean and P. pachyrhizi. RNA-Seq analysis identified a total of 6540 differentially expressed genes (DEGs), which were shared by all four genotypes. The DEGs are involved in defense responses, stress responses, stimulus responses, flavonoid metabolism, and biosynthesis after infection with P. pachyrhizi. A total of 25,377 genes were divided into 33 modules using weighted gene co-expression network analysis (WGCNA). Two modules were significantly associated with pathogen defense. The DEGs were mainly enriched in RNA processing, plant-type hypersensitive response, negative regulation of cell growth, and a programmed cell death process. In conclusion, these results will provide an important resource for mining resistant genes to P. pachyrhizi infection and valuable resources to potentially pyramid quantitative resistance loci for improving soybean germplasm.

Borna disease virus 1 impairs DNA double-strand break repair through the ATR/Chk1 signalling pathway, resulting in learning and memory impairment in rats.

Borna disease virus 1 (BoDV-1) is a highly neurotropic RNA virus that can establish persistent infection in the central nervous system and cause cognitive dysfunction in neonatally infected rats. However, the mechanisms that lead to this cognitive impairment remain unclear. DNA double-strand breaks (DSBs) and their repair are associated with brain development and cognition. If DNA repair in the brain is reduced or delayed and DNA damage accumulates, abnormal cognitive function may result. We generated a rat model of BoDV-1 infection during the neonatal period and assessed behavioural changes using the open field test and Morris water maze. The levels of DSBs were determined by immunofluorescence and comet assays. Western blotting assessed proteins associated with DNA repair pathways. The results showed that BoDV-1 downregulated the ATR/Chk1 signalling pathway in the brain, impairing DNA damage repair and increasing the number of DSBs, which ultimately leads to cognitive dysfunction. Our findings suggest a molecular mechanism by which BoDV-1 interferes with DNA damage repair to cause learning and memory impairment. This provides a theoretical basis for elucidating BoDV-1-induced neurodevelopmental impairment.

2019 Global NAFLD Prevalence: A Systematic Review and Meta-analysis.

BACKGROUND & AIMS: The increasing rates of obesity and type 2 diabetes mellitus may lead to increased prevalence of nonalcoholic fatty liver disease (NAFLD). We aimed to determine the current and recent trends on the global and regional prevalence of NAFLD. METHODS: Systematic search from inception to March 26, 2020 was performed without language restrictions. Two authors independently performed screening and data extraction. We performed meta-regression to determine trends in NAFLD prevalence. RESULTS: We identified 17,244 articles from literature search and included 245 eligible studies involving 5,399,254 individuals. The pooled global prevalence of NAFLD was 29.8% (95% confidence interval [CI], 28.6%-31.1%); of these, 82.5% of included articles used ultrasound to diagnose NAFLD, with prevalence of 30.6% (95% CI, 29.2%-32.0%). South America (3 studies, 5716 individuals) and North America (4 studies, 18,236 individuals) had the highest NAFLD prevalence at 35.7% (95% CI, 34.0%-37.5%) and 35.3% (95% CI, 25.4%-45.9%), respectively. From 1991 to 2019, trend analysis showed NAFLD increased from 21.9% to 37.3% (yearly increase of 0.7%, P < .0001), with South America showing the most rapid change of 2.7% per year, followed by Europe at 1.1%. CONCLUSIONS: Despite regional variation, the global prevalence of NAFLD is increasing overall. Policy makers must work toward reversing the current trends by increasing awareness of NAFLD and promoting healthy lifestyle environments.

Highly Efficient and Selective Visible-Light Driven Photoreduction of CO2 to CO by Metal-Organic Frameworks-Derived NiCoO Porous Microrods.

Photocatalytic CO2 reduction by solar energy into carbonaceous feedstock chemicals is recognized as one of the effective ways to mitigate both the energy crisis and greenhouse effect, which fundamentally relies on the development of advanced photocatalysts. Here, the exploration of porous microrod photocatalysts based on novel NiCoO solid solutions derived from bimetallic metal-organic frameworks (MOFs) is reported. They exhibit overall enhanced photocatalytic performance with both high activity and remarkable selectivity for reducing CO2 into CO under visible-light irradiation, which are superior to most related photocatalysts reported. Accordingly, the Ni0.2 -Co0.8 -O microrod (MR-N0.2 C0.8 O) photocatalyst delivers high efficiency for photocatalytic CO2 reduction into CO at a rate up to ≈277 µmol g-1 h-1 , which is ≈35 times to that of its NiO counterpart. Furthermore, they display a high selectivity of ≈85.12%, which is not only better than that of synthesized Co3 O4 (61.25%) but also superior to that of reported Co3 O4 -based photocatalysts. It is confirmed that the Co and Ni species are responsible for CO2 CO conversion activity and selectivity, respectively. In addition, it is verified, by adjusting the Ni contents, that the band structure of NiCoO microrods can be tailored with favorable reduction band potentials, which thus enhance the selectivity toward CO2 photoreduction.

Increased Risk of Liver-Related Outcomes in Chronic Hepatitis B Patients with Metabolic Syndrome: A Systematic Review and Meta-Analysis.

INTRODUCTION: Chronic hepatitis B (CHB) patients with metabolic syndrome (MetS) may present increased risk of liver-related outcomes (LROs), but prior studies were limited by small sample size and/or conflicting results. Using a systematic review and meta-analytic approach, we aimed to determine the association between MetS and LROs in CHB. METHODS: Two researchers independently screened studies from the PubMed, Embase, Web of Science, and Cochrane Library databases from inception to January 21, 2020, and extracted the data. Estimates were pooled using a random-effects model. RESULTS: We screened 2,228 articles and included 10 eligible studies (18,360 CHB patients, 2,557 with MetS). MetS was significantly associated with LROs overall (odds ratio = 2.45, 95% confidence interval = 1.39-4.32) but not the individual LRO components but subgroup analyses were limited by small study numbers. DISCUSSION/CONCLUSION: MetS is associated with almost 3-folds higher risk of LROs in CHB and should be considered in management decisions. However, additional studies are needed.

Exploring bridge symptoms in HIV-positive people with comorbid depressive and anxiety disorders.

BACKGROUND: The prevalence of comorbid depressive and anxiety disorders in people living with HIV (PLWH) is high. However, it is unclear which symptom is the bridge symptom between depression and anxiety in PLWH. This study aimed to develop symptom networks for depression and anxiety and explore the bridge symptoms and interconnectedness between these disorders in PLWH with comorbid depressive and anxiety disorders. METHODS: A multisite, hospital-based cross-sectional study was conducted from March 2020 to November 2021. Depression and anxiety were measured with the Hospital Anxiety and Depression Scale. We visualized the symptom network using the qgraph package and computed the bridge expected influence of each node. The GLASSO layout was used to generate undirected association networks. RESULTS: A total of 2016 individuals were included in the analysis. In the anxiety cluster, "not feeling relaxed" had the highest bridge expected influence and strength (rbridge expected influence = 0.628, rstrength = 0.903). In the depression cluster, "not feeling cheerful" was identified as having a high bridge expected influence (rbridge expected influence = 0.385). "Not feeling cheerful" and "not feeling relaxed" were the strongest edges across the depression and anxiety clusters (r = 0.30 ± 0.02). CONCLUSIONS: Healthcare professionals should take note when PLWH report severe bridge symptoms. To enhance the levels of perceived cheerfulness and relaxation, positive psychology interventions could be implemented.

A Retrospective Study from a Single Center in China to Develop a Nomogram to Predict One-Year Mortality in Patients with End-Stage Renal Disease Who Are Receiving Hemodialysis.

BACKGROUND The prognosis of end-stage renal disease (ESRD) patients receiving hemodialysis (HD) remains Poor. This retrospective study from a single center in China aimed to develop a nomogram to predict one-year mortality in patients with ESRD on HD. MATERIAL AND METHODS We enrolled 299 ethnic Han Chinese ESRD patients undergoing HD at the Second Affiliated Hospital of Nantong University from April 29, 2011 to January 30, 2021. Univariate and multivariate Cox regression analyses were used to select the predictors incorporated in the prediction model to assess the one-year mortality for ESRD patients receiving HD. We used receiver operating characteristic curves, C-index, and calibration curves to evaluate the performance of the nomogram. The predictive performance of the nomogram was also verified in different subgroup populations. RESULTS The median follow-up time was 23.30 months. The 299 ESRD patients receiving HD were divided into a death group (n=96) and a survival group (n=203), and the incidence of death was 32.11%. The main causes of death were cardiovascular disease, inflammation and cancer. A nomogram containing age, alkaline phosphatase, albumin, cystatin C, total bilirubin, and hypersensitive c-reactive protein was established. The performance of this nomogram was reflected by its moderate predictive ability, especially for patients who were male, had a primary disease of chronic glomerulonephritis, and had no history of comorbidities. CONCLUSIONS We developed and validated an easy-to-use nomogram for predicting the one-year mortality of ESRD patients undergoing HD.

Identification of Quantitative Trait Locus and Candidate Genes for Drought Tolerance in a Soybean Recombinant Inbred Line Population.

With global warming and regional decreases in precipitation, drought has become a problem worldwide. As the number of arid regions in the world is increasing, drought has become a major factor leading to significant crop yield reductions and food crises. Soybean is a crop that is relatively sensitive to drought. It is also a crop that requires more water during growth and development. The aim of this study was to identify the quantitative trait locus (QTL) that affects drought tolerance in soybean by using a recombinant inbred line (RIL) population from a cross between the drought-tolerant cultivar 'Jindou21' and the drought-sensitive cultivar 'Zhongdou33'. Nine agronomic and physiological traits were identified under drought and well-watered conditions. Genetic maps were constructed with 923,420 polymorphic single nucleotide polymorphism (SNP) markers distributed on 20 chromosomes at an average genetic distance of 0.57 centimorgan (cM) between markers. A total of five QTLs with a logarithm of odds (LOD) value of 4.035-8.681 were identified on five chromosomes. Under well-watered conditions and drought-stress conditions, one QTL related to the main stem node number was located on chromosome 16, accounting for 17.177% of the phenotypic variation. Nine candidate genes for drought resistance were screened from this QTL, namely Glyma.16G036700, Glyma.16G036400, Glyma.16G036600, Glyma.16G036800, Glyma.13G312700, Glyma.13G312800, Glyma.16G042900, Glyma.16G043200, and Glyma.15G100700. These genes were annotated as NAC transport factor, GATA transport factor, and BTB/POZ-MATH proteins. This result can be used for molecular marker-assisted selection and provide a reference for breeding for drought tolerance in soybean.

MOFs-Derived Fusiform In2 O3 Mesoporous Nanorods Anchored with Ultrafine CdZnS Nanoparticles for Boosting Visible-Light Photocatalytic Hydrogen Evolution.

The development of efficient visible-light-driven photocatalysts is one of the critically important issues for solar hydrogen production. Herein, high-efficiency visible-light-driven In2 O3 /CdZnS hybrid photocatalysts are explored by a facile oil-bath method, in which ultrafine CdZnS nanoparticles are anchored on NH2 -MIL-68-derived fusiform In2 O3 mesoporous nanorods. It is disclosed that the as-prepared In2 O3 /CdZnS hybrid photocatalysts exhibit enhanced visible-light harvesting, improves charges transfer and separation as well as abundant active sites. Correspondingly, their visible-light-driven H2 production rate is significantly enhanced for more than 185 times to that of pristine In2 O3 nanorods, and superior to most of In2 O3 -based photocatalysts ever reported, representing their promising applications in advanced photocatalysts.

Overexpression of GmMYB14 improves high-density yield and drought tolerance of soybean through regulating plant architecture mediated by the brassinosteroid pathway.

MYB transcription factors (TFs) have been reported to regulate the biosynthesis of secondary metabolites, as well as to mediate plant adaption to abiotic stresses, including drought. However, the roles of MYB TFs in regulating plant architecture and yield potential remain poorly understood. Here, we studied the roles of the dehydration-inducible GmMYB14 gene in regulating plant architecture, high-density yield and drought tolerance through the brassinosteroid (BR) pathway in soybean. GmMYB14 was shown to localize to nucleus and has a transactivation activity. Stable GmMYB14-overexpressing (GmMYB14-OX) transgenic soybean plants displayed a semi-dwarfism and compact plant architecture associated with decreased cell size, resulting in a decrease in plant height, internode length, leaf area, leaf petiole length and leaf petiole angle, and improved yield in high density under field conditions. Results of the transcriptome sequencing suggested the involvement of BRs in regulating GmMYB14-OX plant architecture. Indeed, GmMYB14-OX plants showed reduced endogenous BR contents, while exogenous application of brassinolide could partly rescue the phenotype of GmMYB14-OX plants. Furthermore, GmMYB14 was shown to directly bind to the promoter of GmBEN1 and up-regulate its expression, leading to reduced BR content in GmMYB14-OX plants. GmMYB14-OX plants also displayed improved drought tolerance under field conditions. GmBEN1 expression was also up-regulated in the leaves of GmMYB14-OX plants under polyethylene glycol treatment, indicating that the GmBEN1-mediated reduction in BR level under stress also contributed to drought/osmotic stress tolerance of the transgenic plants. Our findings provided a strategy for stably increasing high-density yield and drought tolerance in soybean using a single TF-encoding gene.

Derivation and validation of prognostic models for predicting survival outcomes in Acute-on-chronic liver failure patients.

Acute-on-chronic liver failure (ACLF) is a syndrome characterized by acute decompensation of chronic liver disease associated with high bacterial infection (BI) and short-term mortality. However, many ACLF prognostic predictive modelsare complicated. The aim of this study is to develop prognostic models for ACLF patients to predict BI and mortality. We retrospective recruited 263 patients with ACLF from Shandong Provincial Hospital and Taizhou Enze Medical Center (Group) Enze Hospital. ACLF was defined according to the Asian Pacific Association for the Study of the Liver (APASL) criteria. Multivariable logistic regression was used to derive prediction models for occurring BI and 28-day mortality in ACLF patients. Ninety seven of 263 patients (37%) occurred BI and 41 of 155 (26%) died within 28 days of admission. C-reactive protein (CRP), glucose, and albumin were the independent predictors for occurring BI during the hospital stay. We also found that hepatic encephalopathy (HE), prothrombin time, activated partial thromboplastin time (APRI), and glucose were the independent predictors of 28-day mortality of ACLF patients. Using logistic regression model, we generated a new modified MELD model (M-MELD) by incorporating HE, APRI, and glucose. AUC of M-MELD model was 0.871, which were significantly higher than MELD score (AUC:0.734), MELD-Na score (AUC:0.742), and integrated MELD score (iMELD) (AUC:0.761). HE, MELD score, APRI, and blood glucose were independent risk factors for 28-day mortality of ACLF patients. The modified MELD model (M-MELD) by incorporating HE, APRI, and glucose has better discriminative performances compared with MELD in predicting 28-day mortality.

Epidemiology of COVID-19: A systematic review and meta-analysis of clinical characteristics, risk factors, and outcomes.

Coronavirus disease 2019 (COVID-19) has become a pandemic, but its reported characteristics and outcomes vary greatly amongst studies. We determined pooled estimates for clinical characteristics and outcomes in COVID-19 patients including subgroups by disease severity (based on World Health Organization Interim Guidance Report or Infectious Disease Society of America/American Thoracic Society criteria) and by country/region. We searched Pubmed, Embase, Scopus, Cochrane, Chinese Medical Journal, and preprint databases from 1 January 2020 to 6 April 2020. Studies of laboratory-confirmed COVID-19 patients with relevant data were included. Two reviewers independently performed study selection and data extraction. From 6007 articles, 212 studies from 11 countries/regions involving 281 461 individuals were analyzed. Overall, mean age was 46.7 years, 51.8% were male, 22.9% had severe disease, and mortality was 5.6%. Underlying immunosuppression, diabetes, and malignancy were most strongly associated with severe COVID-19 (coefficient = 53.9, 23.4, 23.4, respectively, all P < .0007), while older age, male gender, diabetes, and hypertension were also associated with higher mortality (coefficient = 0.05 per year, 5.1, 8.2, 6.99, respectively; P = .006-.0002). Gastrointestinal (nausea, vomiting, abdominal pain) and respiratory symptoms (shortness of breath, chest pain) were associated with severe COVID-19, while pneumonia and end-organ failure were associated with mortality. COVID-19 is associated with a severe disease course in about 23% and mortality in about 6% of infected persons. Individuals with comorbidities and clinical features associated with severity should be monitored closely, and preventive efforts should especially target those with diabetes, malignancy, and immunosuppression.