GPCRs steer Gi and Gs selectivity via TM5-TM6 switches as revealed by structures of serotonin receptors.

Serotonin (or 5-hydroxytryptamine, 5-HT) is an important neurotransmitter that activates 12 different G protein-coupled receptors (GPCRs) through selective coupling of Gs, Gi, or Gq proteins. The structural basis for G protein subtype selectivity by these GPCRs remains elusive. Here, we report the structures of the serotonin receptors 5-HT4, 5-HT6, and 5-HT7 with Gs, and 5-HT4 with Gi1. The structures reveal that transmembrane helices TM5 and TM6 alternate lengths as a macro-switch to determine receptor's selectivity for Gs and Gi, respectively. We find that the macro-switch by the TM5-TM6 length is shared by class A GPCR-G protein structures. Furthermore, we discover specific residues within TM5 and TM6 that function as micro-switches to form specific interactions with Gs or Gi. Together, these results present a common mechanism of Gs versus Gi protein coupling selectivity or promiscuity by class A GPCRs and extend the basis of ligand recognition at serotonin receptors.

Omicron breakthrough infections after triple-dose inactivated COVID-19 vaccination: A comprehensive analysis of antibody and T-cell responses.

This study longitudinally evaluated the immune response in individuals over a year after receiving three doses of an inactivated SARS-CoV-2 vaccine, focusing on reactions to Omicron breakthrough infections. From 63 blood samples of 37 subjects, results showed that the third booster enhanced the antibody response against Alpha, Beta, and Delta VOCs but was less effective against Omicron. Although antibody titres decreased post-vaccination, SARS-CoV-2-specific T-cell responses, both CD4+ and CD8+, remained stable. Omicron breakthrough infections significantly improved neutralization against various VOCs, including Omicron. However, the boost in antibodies against WT, Alpha, Beta, and Delta variants was more pronounced. Regarding T cells, breakthrough infection predominantly boosted the CD8+ T-cell response, and the intensity of the spike protein-specific T-cell response was roughly comparable between WT and Omicron BA.5.

WZ-3146 acts as a novel small molecule inhibitor of KIF4A to inhibit glioma progression by inducing apoptosis.

BACKGROUND: Glioma is considered the most common primary malignant tumor of the central nervous system. Although traditional treatments have not achieved satisfactory outcomes, recently, targeted therapies for glioma have shown promising efficacy. However, due to the single-target nature of targeted therapy, traditional targeted therapies are ineffective; thus, novel therapeutic targets are urgently needed. METHODS: The gene expression data for glioma patients were derived from the GEO (GSE4290, GSE50161), TCGA and CGGA databases. Next, the upregulated genes obtained from the above databases were cross-analyzed, finally, 10 overlapping genes (BIRC5, FOXM1, EZH2, CDK1, KIF11, KIF4A, NDC80, PBK, RRM2, and TOP2A) were ultimately screened and only KIF4A expression has the strongest correlation with clinical characteristics in glioma patients. Futher, the TCGA and CGGA database were utilized to explore the correlation of KIF4A expression with glioma prognosis. Then, qRT-PCR and Western blot was used to detect the KIF4A mRNA and protein expression level in glioma cells, respectively. And WZ-3146, the small molecule inhibitor targeting KIF4A, were screened by Cmap analysis. Subsequently, the effect of KIF4A knockdown or WZ-3146 treatment on glioma was measured by the MTT, EdU, Colony formation assay and Transwell assay. Ultimately, GSEA enrichment analysis was performed to find that the apoptotic pathway could be regulated by KIF4A in glioma, in addition, the effect of WZ-3146 on glioma apoptosis was detected by flow cytometry and Western blot. RESULTS: In the present study, we confirmed that KIF4A is abnormally overexpressed in glioma. In addition, KIF4A overexpression is a key indicator of glioma prognosis; moreover, suppressing KIF4A expression can inhibit glioma progression. We also discovered that WZ-3146, a small molecule inhibitor of KIF4A, can induce apoptosis in glioma cells and exhibit antiglioma effects. CONCLUSION: In conclusion, these observations demonstrated that targeting KIF4A can inhibit glioma progression. With further research, WZ-3146, a small molecule inhibitor of KIF4A, could be combined with other molecular targeted drugs to cooperatively inhibit glioma progression.

PacBio single-molecule long-read sequencing provides new insights into the complexity of full-length transcripts in oriental river prawn, macrobrachium nipponense.

BACKGROUND: Oriental river prawn (Macrobrachium nipponense) is one of the most dominant species in shrimp farming in China, which is a rich source of protein and contributes to a significant impact on the quality of human life. Thus, more complete and accurate annotation of gene models are important for the breeding research of oriental river prawn. RESULTS: A full-length transcriptome of oriental river prawn muscle was obtained using the PacBio Sequel platform. Then, 37.99 Gb of subreads were sequenced, including 584,498 circular consensus sequences, among which 512,216 were full length non-chimeric sequences. After Illumina-based correction of long PacBio reads, 6,599 error-corrected isoforms were identified. Transcriptome structural analysis revealed 2,263 and 2,555 alternative splicing (AS) events and alternative polyadenylation (APA) sites, respectively. In total, 620 novel genes (NGs), 197 putative transcription factors (TFs), and 291 novel long non-coding RNAs (lncRNAs) were identified. CONCLUSIONS: In summary, this study offers novel insights into the transcriptome complexity and diversity of this prawn species, and provides valuable information for understanding the genomic structure and improving the draft genome annotation of oriental river prawn.

Universal DNA-Based Sensing Toolbox for Programming Cell Functions.

By recombining natural cell signaling systems and further reprogramming cell functions, use of genetically engineered cells and bacteria as therapies is an innovative emerging concept. However, the inherent properties and structures of the natural signal sensing and response pathways constrain further development. We present a universal DNA-based sensing toolbox on the cell surface to endow new signal sensing abilities for cells, control cell states, and reprogram multiple cell functions. The sensing toolbox contains a triangular-prismatic-shaped DNA origami framework and a sensing core anchored inside the internal confined space to enhance the specificity and efficacy of the toolbox. As a proof of principle, the sensing toolbox uses the customizable sensing core with signal sensing switches and converters to recognize unconventional signal inputs, deliver functional components to cells, and then control cell responses, including specific tumor cell death, immune cell disinhibition and adhesion, and bacterial expression. This work expands the diversity of cell sensing signals and reprograms biological functions by constructing nanomechanical-natural hybrid cells, providing new strategies for engineering cells and bacteria in diagnosis and treatment applications.

A Trial of Lopinavir-Ritonavir in Adults Hospitalized with Severe Covid-19.

BACKGROUND: No therapeutics have yet been proven effective for the treatment of severe illness caused by SARS-CoV-2. METHODS: We conducted a randomized, controlled, open-label trial involving hospitalized adult patients with confirmed SARS-CoV-2 infection, which causes the respiratory illness Covid-19, and an oxygen saturation (Sao2) of 94% or less while they were breathing ambient air or a ratio of the partial pressure of oxygen (Pao2) to the fraction of inspired oxygen (Fio2) of less than 300 mm Hg. Patients were randomly assigned in a 1:1 ratio to receive either lopinavir-ritonavir (400 mg and 100 mg, respectively) twice a day for 14 days, in addition to standard care, or standard care alone. The primary end point was the time to clinical improvement, defined as the time from randomization to either an improvement of two points on a seven-category ordinal scale or discharge from the hospital, whichever came first. RESULTS: A total of 199 patients with laboratory-confirmed SARS-CoV-2 infection underwent randomization; 99 were assigned to the lopinavir-ritonavir group, and 100 to the standard-care group. Treatment with lopinavir-ritonavir was not associated with a difference from standard care in the time to clinical improvement (hazard ratio for clinical improvement, 1.31; 95% confidence interval [CI], 0.95 to 1.80). Mortality at 28 days was similar in the lopinavir-ritonavir group and the standard-care group (19.2% vs. 25.0%; difference, -5.8 percentage points; 95% CI, -17.3 to 5.7). The percentages of patients with detectable viral RNA at various time points were similar. In a modified intention-to-treat analysis, lopinavir-ritonavir led to a median time to clinical improvement that was shorter by 1 day than that observed with standard care (hazard ratio, 1.39; 95% CI, 1.00 to 1.91). Gastrointestinal adverse events were more common in the lopinavir-ritonavir group, but serious adverse events were more common in the standard-care group. Lopinavir-ritonavir treatment was stopped early in 13 patients (13.8%) because of adverse events. CONCLUSIONS: In hospitalized adult patients with severe Covid-19, no benefit was observed with lopinavir-ritonavir treatment beyond standard care. Future trials in patients with severe illness may help to confirm or exclude the possibility of a treatment benefit. (Funded by Major Projects of National Science and Technology on New Drug Creation and Development and others; Chinese Clinical Trial Register number, ChiCTR2000029308.).

RNase H-Driven crRNA Switch Circuits for Rapid and Sensitive Detection of Various Analytical Targets.

The clustered regularly interspaced short palindromic repeats (CRISPR/Cas12a) system has exhibited great promise in the rapid and sensitive molecular diagnostics for its trans-cleavage property. However, most CRISPR/Cas system-based detection methods are designed for nucleic acids and require target preamplification to improve sensitivity and detection limits. Here, we propose a generic crRNA switch circuit-regulated CRISPR/Cas sensor for the sensitive detection of various targets. The crRNA switch is engineered and designed in a blocked state but can be activated in the presence of triggers, which are target-induced association DNA to initiate the trans-cleavage activity of Cas12a for signal reporting. Additionally, RNase H is introduced to specifically hydrolyze RNA duplexed with the DNA trigger, resulting in the regeneration of the trigger to activate more crRNA switches. Such a combination provides a generic and sensitive strategy for the effective sensing of the p53 sequence, thrombin, and adenosine triphosphate. The design is incorporated with nucleic acid nanotechnology and extensively broadens the application scope of the CRISPR technology in biosensing.

A DNA Nanodevice-Based Platform with Diverse Capabilities.

Social biotic colonies often perform intricate tasks by interindividual communication and cooperation. Inspired by these biotic behaviors, a DNA nanodevice community is proposed as a universal and scalable platform. The modular nanodevice as the infrastructure of platform contains a DNA origami triangular prism framework and a hairpin-swing arm machinery core. By coding and decoding a signal domain on the shuttled output strand in different nanodevices, an orthogonal inter-nanodevice communication network is established to connect multi-nanodevices into a functional platform. The nanodevice platform enables implementation of diverse tasks, including signal cascading and feedback, molecular input recording, distributed logic computing, and modeling of simulation for virus transmission. The nanodevice platform with powerful compatibility and programmability presents an elegant example of the combination of the distributed operation of multiple devices and the complicated interdevice communication network, and may become a new generation of intelligent DNA nanosystems.

Fine mapping of qAHPS07 and functional studies of AhRUVBL2 controlling pod size in peanut (Arachis hypogaea L.).

Cultivated peanut (Arachis hypogaea L.) is an important oil and cash crop. Pod size is one of the major traits determining yield and commodity characteristic of peanut. Fine mapping of quantitative trait locus (QTL) and identification of candidate genes associated with pod size are essential for genetic improvement and molecular breeding of peanut varieties. In this study, a major QTL related to pod size, qAHPS07, was fine mapped to a 36.46 kb interval on chromosome A07 using F2 , recombinant inbred line (RIL) and secondary F2 populations. qAHPS07 explained 38.6%, 23.35%, 37.48%, 25.94% of the phenotypic variation for single pod weight (SPW), pod length (PL), pod width (PW) and pod shell thickness (PST), respectively. Whole genome resequencing and gene expression analysis revealed that a RuvB-like 2 protein coding gene AhRUVBL2 was the most likely candidate for qAHPS07. Overexpression of AhRUVBL2 in Arabidopsis led to larger seeds and plants than the wild type. AhRUVBL2-silenced peanut seedlings represented small leaves and shorter main stems. Three haplotypes were identified according to three SNPs in the promoter of AhRUVBL2 among 119 peanut accessions. Among them, SPW, PW and PST of accessions carrying Hap_ATT represent 17.6%, 11.2% and 26.3% higher than those carrying Hap_GAC，respectively. In addition, a functional marker of AhRUVBL2 was developed. Taken together, our study identified a key functional gene of peanut pod size, which provides new insights into peanut pod size regulation mechanism and offers practicable markers for the genetic improvement of pod size-related traits in peanut breeding.

Targeting copper death genotyping associated gene RARRES2 suppresses glioblastoma progression and macrophages infiltration.

BACKGROUND: Copper homeostasis is associated with malignant biological behavior in various tumors. The excessive accumulation of copper can induce tumor death, which is named cuproptosis, and it is also closely related to tumor progression and the formation of the immune microenvironment. However, the associations of cuproptosis with glioblastoma (GBM) prognosis and microenvironment construction are poorly understood. METHOD: First, TCGA and GEO (GSE83300, GSE74187) merged datasets were used to analyze the association of cuproptosis-related genes (CRGs) with GBM. Then, we performed cluster analysis of CRGs in GBM from the GEO (GSE83300, GSE74187) and TCGA merged datasets. Subsequently, the prognostic risk model was constructed by least absolute shrinkage and selection operator (LASSO) according to gene expression features in CRG clusters. Next, we performed a series of in-depth analyses, including tumor mutational burden (TMB) analysis, cluster analysis, and GBM IDH status prediction. Finally, RARRES2 was identified as a target gene for GBM treatment, especially IDH wild-type GBM. In addition, we further analyzed the correlation of CRG clusters and RARRES2 expression with the GBM immune microenvironment by ESTIMATE and CIBERSORT analyses. In vitro experiments were conducted to demonstrate that targeting RARRES2 inhibits glioblastoma progression and macrophage infiltration, particularly IDH wild-type GBM. RESULTS: In the present study, we demonstrated that the CRG cluster was closely related to GBM prognosis and immune cell infiltration. Moreover, the prognostic risk model constructed with the three genes (MMP19, G0S2, RARRES2) associated with the CRG clusters could well evaluate the prognosis and immune cell infiltration in GBM. Subsequently, after further analyzing the tumor mutational burden (TMB) in GBM, we confirmed that RARRES2 in the prognostic risk model could be used as a crucial gene signature to predict the prognosis, immune cell infiltration and IDH status of GBM patients. CONCLUSION: This study fully revealed the potential clinical impact of CRGs on GBM prognosis and the microenvironment, and determined the effect of the crucial gene (RARRES2) on the prognosis and tumor microenvironment construction of GBM, meanwhile, our study also revealed over-expressed RARRES2 is related to the IDH satus of GBM, which provides a novel strategy for the treatment of GBM, particularly IDH wild-type GBM.

The creation and validation of predictive models to assess the risk of unfavorable outcomes following hybrid total arch repair for Stanford type A aortic dissection.

BACKGROUND: The objective of this study was to develop and validate a nomogram for the individualized prediction of adverse events in patients with Stanford type A aortic dissection (TAAD) undergoing hybrid total aortic arch repair. METHODS: From April 2019 to April 2022, we conducted a comprehensive review of the medical records of Stanford type A aortic dissection patients who underwent hybrid total aortic arch repair surgery at our hospital. Patients were separated into two groups based on whether or not a composite adverse event occurred following surgery. Using univariate and multivariate analyses of logistic regression, the prediction model was created. Construct risk prediction models utilizing nomograms and evaluate their precision, discrimination, and clinical utility. RESULTS: Age, platelets, serum blood urea nitrogen, and ascending aortic diameter were the variables included in the nomogram by univariate and multivariate analysis. The risk model performed well in internal validation, with an area under the curve (AUC) of 0.829. The calibration curve demonstrated good agreement between predicted and actual probabilities (Hosmer-Lemeshow test, P = 0.22). Clinical decision analysis curves demonstrate predictive nomograms' clinical utility. CONCLUSION: This study created and validated a nomogram for predicting the risk of composite endpoint events in TAAD patients undergoing hybrid total aortic arch repair. The nomogram can help determine the severity of a patient's condition and provide a more personalized diagnosis and treatment.

Adenovirus-IL-10 relieves chronic rejection after mouse heart transplantation by inhibiting miR-155 and activating SOCS5.

Objective: Chronic rejection remains the main factor that influence long-term survival of patients after heart transplantation. Interleukin-10 (IL-10) play critical role in macrophages-mediated transplant immune responses. We investigated the mechanism of IL-10 in macrophage related chronic rejection after mouse heart transplantation. Methods: Mouse heart transplant chronic rejection model was established to evaluate pathological changes in the allograft. Myocardial interstitial fibrosis, apoptosis, and inflammatory factor levels were detected in ad-IL-10-treated mice. The positive iNOS+ and Arg-1+ expressions, macrophage subset changes, and the proportion of regulatory T-cells (Tregs) and TIGIT+ Tregs were quantified by flow. In in vitro experiments, ad-IL-10 was transfected into macrophages followed by detection of apoptosis, phagocytosis, and CD163, CD16/32, and CD206 expression. The expression and relationships between IL-10, miR-155, and SOCS5 were also detected and verified. A rescue experiment was performed to evaluate macrophage function through the combined treatment of ad-IL-10 and overexpression of miR-155. Results: Significantly decreased IL-10 expression in chronic rejection during mouse heart transplantation was observed. Ad-IL-10-treated mice showed decreased pathological injury, perivascular fibrosis, apoptosis, inflammation, and iNOS+ and CD16/32+ expression, and increased Treg/TIGIT+ Treg cell, Arg-1+ and CD206+ cell proportion. Ad-IL-10-treated macrophages in vitro showed reduced apoptosis, improved phagocytosis, and M2 polarization. Mechanically, IL-10 negatively regulated miR-155 to activate SOCS5. Overexpression of miR-155 reversed IL-10 mediated-positive regulation of macrophage function. Conclusion: IL-10 downregulated miR-155 and activated SOCS5, thereby promoting macrophage M2 polarization to relieve chronic rejection after heart transplantation.

Clenbuterol Prevents Mechanical Unloading-Induced Myocardial Atrophy via Upregulation of Transient Receptor Potential Channel-3.

Left ventricular assist device in combination with clenbuterol has been demonstrated to significantly improve heart function in patients with advanced heart failure. However, the roles of clenbuterol in mechanical unloading and its underlying mechanism are poorly understood. A rat abdominal heart transplantation model has been developed to mimic mechanical unloading of the heart. The recipient rats were randomly segregated into experimental groups for the daily administration of either saline (the "Trans" group; n = 13) or clenbuterol (2 mg/kg, the "Trans + CB" group; n = 12). Another group of 10 rats served as a treatment mimic control/sham animals (the "Sham" group). All interventions were performed via intraperitoneal injections once daily for 4 weeks. The Trans group animals exhibited myocardial atrophy and dysfunction with decreased expression levels of transient receptor potential channel 3 (TRPC3) and phospholipase C-ß1 (PLC-ß1) at 4 weeks post-transplantation. Administration of clenbuterol improved cardiac function, prevented myocardial atrophy, and restored expression of TRPC3 and PLC-ß1 in the unloaded hearts of the "Trans + CB" animals at 4 weeks post-transplantation. Silencing of the TRPC3 gene by siRNA inhibited the pro-hypertrophic effect of clenbuterol in the rat primary cardiomyocytes in vitro. Furthermore, U73122, an inhibitor of the PLC-ß1/diacylglycerol (DAG) pathway, significantly attenuated clenbuterol-induced upregulation of TRPC3 in cardiomyocytes. These findings suggest that the anti-atrophic effect of clenbuterol may be dependent on the upregulation of TRPC3 through the activation of the PLC-ß1/DAG pathway during mechanical unloading. The results of our study reveal a potential target for the prevention and treatment of mechanical unloading-induced myocardial atrophy.

Nano-Biohybrid DNA Engager That Reprograms the T-Cell Receptor.

Although engineered T cells with transgenic chimeric antigen receptors (CARs) have made a breakthrough in cancer therapeutics, this approach still faces many challenges in the specificity, efficacy, and self-safety of genetic engineering. Here, we developed a nano-biohybrid DNA engager-reprogrammed T-cell receptor (EN-TCR) system to improve the specificity and efficacy, mitigate the excessive activation, and shield against risks from transgenesis, thus achieving a diversiform and precise control of the T-cell response. Utilizing modular assembly, the EN-TCR system can graft different specificities on T cells via antibody assembly. Besides, the designability of DNA hybridization enables precise target recognition by the library of multiantigen cell recognition circuits and allows gradual tuning of the T-cell activation level by the signaling switch and independent control over different types of T cells. Furthermore, we demonstrated the effectiveness of the system in tumor models. Together, this study provides a nongenetic T-cell engineering strategy to overcome major hindrances in T-cell therapy and may be extended to a general and convenient cell engineering strategy.

Integrated analysis of the miRNA and mRNA expression profiles in Leiocassis longirostris at gonadal maturation.

Leiocassis longirostris is a commercially important fish species that shows a sexually dimorphic growth pattern. A lack of molecular data from the gonads of this species has hindered research and selective breeding efforts. In this study, we conducted a comprehensive analysis of the expression profile of miRNA and mRNA to explore their regulatory roles in the gonadal maturation stage of L. longirostris. We identified 60 differentially expressed miRNAs and 20,752 differentially expressed genes by sequencing. A total of 90 miRNAs and 21 target genes involved in gonad development and sex determination were identified. Overall, the results of this study enhance our understanding of the molecular mechanisms underlying sex determination and differentiation and provide valuable genomic information for the selective breeding of L. longirostris.

The impact of particulate matter 2.5 on the risk of hepatocellular carcinoma: a meta-analysis.

OBJECTIVE: The convoluted element of PM2.5 may cause various biological reactions. Nowadays, few studies have indicated the long-term health effects of PM2.5 on HCC. Therefore, this meta-analysis first aims to obtain more precise estimates of the effects of PM2.5 exposure on HCC to assess the strength of the evidence. METHODS: A combination of computer and manual retrieval was used to search in Medline through PubMed, EMBASE and Web of Science. Review Manager 5.3 software was used to examine the heterogeneity among the studies. RESULTS: Finally, 8 qualified articles meet the inclusion criteria. The results were I2 = 0%, P > 0.1 indicating that there was no heterogeneity. The results showed that the concentration of PM2.5 increased by 10 µg/m3 was significantly correlated with liver cancer, and HR was 1.22 (95% CI 1.14-1.30, P < 0.05), indicating that maternal exposure to PM2.5 was positively correlated with liver cancer. CONCLUSIONS: Our meta-analysis showed that the patients with HCC significance related to PM2.5 exposure. However, more studies investigating the combined effects of different air pollutants on HCC incidence are warranted to provide more comprehensive evidence for assessing the different levels impacts of PM2.5 exposure on HCC incidence.

Unusual Tetrahydropyridoindole-Containing Tetrapeptides with Human Nicotinic Acetylcholine Receptors Targeting Activity Discovered from Antarctica-Derived Psychrophilic Pseudogymnoascus sp. HDN17-933.

Chemical investigation of the psychrophilic fungus Pseudogymnoascus sp. HDN17-933 derived from Antarctica led to the discovery of six new tetrapeptides psegymamides A-F (1-6), whose planar structures were elucidated by extensive NMR and MS spectrometric analyses. Structurally, psegymamides D-F (4-6) possess unique backbones bearing a tetrahydropyridoindoles unit, which make them the first examples discovered in naturally occurring peptides. The absolute configurations of structures were unambiguously determined using solid-phase total synthesis assisted by Marfey's method, and all compounds were evaluated for their inhibition of human (h) nicotinic acetylcholine receptor subtypes. Compound 2 showed significant inhibitory activity. A preliminary structure-activity relationship investigation revealed that the tryptophan residue and the C-terminal with methoxy group were important to the inhibitory activity. Further, the high binding affinity of compound 2 to hα4ß2 was explained by molecular docking studies.

Remdesivir in adults with severe COVID-19: a randomised, double-blind, placebo-controlled, multicentre trial.

BACKGROUND: No specific antiviral drug has been proven effective for treatment of patients with severe coronavirus disease 2019 (COVID-19). Remdesivir (GS-5734), a nucleoside analogue prodrug, has inhibitory effects on pathogenic animal and human coronaviruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in vitro, and inhibits Middle East respiratory syndrome coronavirus, SARS-CoV-1, and SARS-CoV-2 replication in animal models. METHODS: We did a randomised, double-blind, placebo-controlled, multicentre trial at ten hospitals in Hubei, China. Eligible patients were adults (aged ≥18 years) admitted to hospital with laboratory-confirmed SARS-CoV-2 infection, with an interval from symptom onset to enrolment of 12 days or less, oxygen saturation of 94% or less on room air or a ratio of arterial oxygen partial pressure to fractional inspired oxygen of 300 mm Hg or less, and radiologically confirmed pneumonia. Patients were randomly assigned in a 2:1 ratio to intravenous remdesivir (200 mg on day 1 followed by 100 mg on days 2-10 in single daily infusions) or the same volume of placebo infusions for 10 days. Patients were permitted concomitant use of lopinavir-ritonavir, interferons, and corticosteroids. The primary endpoint was time to clinical improvement up to day 28, defined as the time (in days) from randomisation to the point of a decline of two levels on a six-point ordinal scale of clinical status (from 1=discharged to 6=death) or discharged alive from hospital, whichever came first. Primary analysis was done in the intention-to-treat (ITT) population and safety analysis was done in all patients who started their assigned treatment. This trial is registered with ClinicalTrials.gov, NCT04257656. FINDINGS: Between Feb 6, 2020, and March 12, 2020, 237 patients were enrolled and randomly assigned to a treatment group (158 to remdesivir and 79 to placebo); one patient in the placebo group who withdrew after randomisation was not included in the ITT population. Remdesivir use was not associated with a difference in time to clinical improvement (hazard ratio 1·23 [95% CI 0·87-1·75]). Although not statistically significant, patients receiving remdesivir had a numerically faster time to clinical improvement than those receiving placebo among patients with symptom duration of 10 days or less (hazard ratio 1·52 [0·95-2·43]). Adverse events were reported in 102 (66%) of 155 remdesivir recipients versus 50 (64%) of 78 placebo recipients. Remdesivir was stopped early because of adverse events in 18 (12%) patients versus four (5%) patients who stopped placebo early. INTERPRETATION: In this study of adult patients admitted to hospital for severe COVID-19, remdesivir was not associated with statistically significant clinical benefits. However, the numerical reduction in time to clinical improvement in those treated earlier requires confirmation in larger studies. FUNDING: Chinese Academy of Medical Sciences Emergency Project of COVID-19, National Key Research and Development Program of China, the Beijing Science and Technology Project.

Precursor-Directed Biosynthesis of Talaroenamine Derivatives Using a Yellow River Wetland-Derived Penicillium malacosphaerulum.

Precursor-directed biosynthesis was used to introduce selected aniline derivatives into the talaroenamine pathway, which had recently been defined from a Yellow River wetland-derived Penicillim malacosphaerulum HPU-J01. The known talaroenamine B (1) and six previously undescribed talaroenamine derivatives, talaroenamines F-K (2-7), were generated and structurally characterized. The aniline derivatives are introduced via nonenzymatic addition to the reactive intermediate cyclohexanedione. Compound 2 was active against Bacillus cereus with an MIC value of 0.85 µg/mL.

Integrative analysis identifies the quality advantage and corresponding regulatory mechanism of paddy field-cultured crayfish (Procambarus clarkii).

Procambarus clarkii is the dominant economic variety of crayfish in China, and paddy field shrimp cultivation is an organic mode of traditional rice-fish cultivation, with paddy field shrimp being the country's prevailing aquatic product. However, little has been reported on the differences in meat quality and digestive ability between paddy field and pond fish. In this study, the muscle composition and digestive function regulation of P. clarkii in ponds and paddies were studied to explore the influence of paddy field culture on P. clarkii quality. The results showed that the muscle composition of paddy field shrimp was significantly changed, with increased protein and decreased lipid levels. Through the study of the hepatopancreas and intestinal microbial diversity of P. clarkii, we hypothesized that rice farming may cause changes in its bacterial spectrum, stimulate the digestive functions of its intestines and hepatopancreas, cause differential expression of multi-substance metabolic pathways, and ultimately result in the substances' deposition in its muscles. This study revealed the impact of rice cultivation on P. clarkii from the perspective of meta-metabolism, and it demonstrated the advantages of paddy field shrimp cultivation.Key points• We explored the influence of paddy field culture on P. clarkii quality.• Muscle composition of paddy field shrimp was significantly changed, with increased protein and decreased lipid levels in paddy field.• Rice farming caused changes in its bacterial spectrum and stimulated the digestive functions of hepatopancreas.