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In earthquake engineering, loading strain rate has an important influence on the mechanical properties of rock. A systematical experimental study is conducted to investigate the strain rate effect of limestone, obtained from a post-earthquake Hongshiyan landslide area in southwest China. Basic mechanical parameters, deformation failure patterns, and energy characteristics are studied. The results show that an increase in the strain rate leads to an exponential increase in the peak stress and a logarithmic increase in the elastic modulus. Rock failure patterns, including axial splitting failure, combined shear-split failure, and shear failure, are dominantly controlled by the influence of confining pressure. Energy curves can be divided into four stages: initial compression, elastic, yield, and post-peak stage. The proportion of elastic energy and dissipated energy increase and decrease with the increase of strain rate, respectively. An obvious threshold divided the stress-strain curve of pre-peak period into the stable part and rapid growth part. A full-range strain rate model is proposed to fit the dynamic increasing factor, and the controlling parameters can be obtained directly, which overcomes the problem of discontinuity at the junction of middle strain rate and high strain rate. [ABSTRACT FROM AUTHOR]

During the reservoir filling of many high arch dams, it was observed that the valley slopes on both sides deformed towards the river. The measured value of valley narrowing lateral deformation (VNLD) reached 89.54 mm by October 2018. This rare phenomenon contradicts the traditional experience of dam engineering and lacks a convincing explanation. An arch dam project in China is selected as a case study to analyze the mechanism of the VNLD. Based on a comprehensive analysis of the geological background and the VNLD measurements, a numerical study is performed to identify the main factors that may contribute to the VNLD phenomenon. It is concluded that the time-dependent valley deformation is due to the rheological behaviour of rock mass with the change of hydrogeological conditions. The artesian water head in the deep-confined aquifer is increased and the mechanical parameters in fault and shear zones are weakened after reservoir filling, which is associated with the specific hydrogeological structures. The rise of artesian water head is the main induced factor that contributes to the uplift deformation, which is observed at the dam site, and can cause the VNLD in the horizontal direction. The simulated results considering these factors agreed well with the observed data. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study on the mechanical behavior and permeability evolution of basalt, drilled from the dam foundation of the Baihetan Hydropower Station in China. Two groups of triaxial unloading creep tests under hydro-mechanical coupling conditions were conducted. Based on the experimental results, creep deformation and failure characteristics of basalt were investigated. It was found that the relationship between the confining pressure and steady creep rate could be described satisfactorily by an exponential function. A tensile-shear failure mode was observed for basalt under the action of unloading confining pressure and hydraulic-mechanical coupling. The permeability evolution of basalt in the unloading creep process exhibited phased characteristics: permeability decreased in the initial loading phase and remained stable for a certain range of confining pressure in the steady creep phase. Exponential functions were also used to describe the evolution of permeability and confining pressure. The results of this study can provide a comprehensive understanding for the long-term stability assessment of basalt under coupled hydro-mechanical conditions. [ABSTRACT FROM AUTHOR]

Background: As non-coding RNA molecules of more than 200 bp in length, long non-coding RNAs (lncRNAs) play a variety of roles in biological processes, including regulating the immune responses to bacterial infections. In recent years, there have been many in-depth studies on mammalian lncRNAs, but the relevant studies in fish are very limited. Meanwhile, since lncRNAs are not conserved among species, it is difficult to apply the existing results directly to unstudied species. Results: To obtain the information of lncRNAs in Megalobrama amblycephala, one of the most economically important freshwater fish in China, also to better understand the biological significance of lncRNAs in the immunity system, the fish liver at 0, 4, 12, 24, and 72 h post Aeromonas hydrophila infection (hpi) were obtained for lncRNA-sequencing (lncRNA-seq). A total of 14,849 lncRNAs were identified, and 2196 lncRNAs showed significant differences at different time points post A. hydrophila infection. Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses showed that the target genes of the differentially expressed lncRNAs were enriched in several pathways related to immune such as apoptosis, inflammation, and immune response. Time-specific modules were then identified, using weighted correlation network analysis (WGCNA), and 28 modules significantly correlated with different time point after infection were found. Furthermore, four immune-related genes and six lncRNAs in the time-specific modules were subsequently verified by RT-qPCR. Conclusions: The above findings reveal the discovery of widespread differentially expressed lncRNAs in the M. amblycephala liver post A. hydrophila infection, suggesting that lncRNAs might participate in the regulation of host response to bacterial infection, enriching the information of lncRNAs in teleost and providing a resources basis for further studies on the immune function of lncRNAs. [ABSTRACT FROM AUTHOR]

Megalobrama amblycephala is one of the most economically important freshwater fish in China, and the bacterial septicemia caused by Aeromonas hydrophila is a serious threat to the breeding industry of M. amblycephala. Unfortunately, the characterization of long noncoding RNA (lncRNA) in response to A. hydrophila infection has not been performed in M. amblycephala. To better understand the biological significance of lncRNA in the immune system, we identified two lncRNA, named MSTRG.5748.1 and MSTRG.7894.1, as playing critical roles in the antibacterial response of M. amblycephala. After separating the nucleus and cytoplasm of the hepatocytes from M. amblycephala , cellular localization of MSTRG.5748.1 and MSTRG.7894.1 was performed to predict their functions. The results showed that MSTRG.5748.1 was mainly expressed in the nucleus, suggesting that its functions are mostly to regulate the expression of downstream genes through epistasis and transcription. MSTRG.7894.1 existed in both the nucleus and cytoplasm, which indicated that it has many regulatory modes. qPCR analysis showed that MSTRG.5748.1 and MSTRG.7894.1 were expressed in the immune-related organs of M. amblycephala , and significantly changed in the liver after A. hydrophila infection. RNA-seq analysis revealed that differentially expressed genes (DEGs) were mainly enriched in antigen processing and presentation via MHC class I, RIG-I-like receptor (RLR) signaling pathway, and IFN-related pathway, and a large number of pathway-related genes were significantly regulated after lncRNA overexpression in muscle cell of M. amblycephala. Overexpression of MSTRG.5748.1 and MSTRG.7894.1 significantly inhibited the expression of STING and IFN , significantly upregulated muscle cell viability, and promoted cell proliferation by targeting STING and IFN. • lncRNA were significantly induced by bacterial infection in immune tissues. • lncRNA regulated the expression of inflammatory cytokines and antibacterial genes. • lncRNA can promote cell proliferation, and reducing cell apoptosis. [ABSTRACT FROM AUTHOR]

The Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway is involved in regulating the body's immunity, cell proliferation, differentiation, and apoptosis. Members of the STAT family have been extensively studied in different mammalian species. However, there are few studies on the STAT family genes in farmed economic fish. In this study, eight STAT genes including STAT1a , STAT1b, STAT2 , STAT3 , STAT4 , STAT5a , STAT5b and STAT6 , in blunt snout bream (Megalobrama amblycephala), an economically important fish in China, were identified and characterized. Analyses of gene location, phylogeny and conserved synteny were conducted to infer the evolutionary origin of these STAT family genes. Furthermore, the evolutionary origin model of STATs was constructed based on the 2R hypothesis and teleost genome duplication (TGD) hypothesis, which clarified the evolutionary origin of the eight STATs in blunt snout bream. Besides, expression of the eight STATs was detected in 10 tissues of healthy blunt snout bream, which showed different expression patterns, and all had the highest level in the blood. In addition, expression of the STATs was significantly induced in the spleen, liver, and kidney after infection of Aeromonas hydrophila , suggesting that they play an important role in protecting the host from pathogens. In general, the evolution of cytokine-related genes parallels that of the immune system, which has likely been a main evolutionary driver. Therefore, the evolutionary model of STAT genes, constructed in the non-model organism pioneeringly, may provide some enlightenment for the evolution of the fish STAT family genes and their involvement in the immune function. • Eight STAT genes were identified in blunt snout bream. • An evolutionary model of the STAT family genes was constructed. • Expression of STAT genes was detected in healthy blunt snout bream. • Expression of STAT genes was examined after Aeromonas hydrophila infection. [ABSTRACT FROM AUTHOR]

• The number of listeriosis cases in China may have been underestimated previously. • Healthcare-associated infections represented a large proportion of listeriosis cases in this study. • Perinatal cases in mainland China accounted for a much higher proportion than what has usually been described. The aim of this study was to conduct a systematic review to better understand the epidemiological and clinical characteristics of listeriosis patients in mainland China. The six most widely used Chinese and English language databases were searched. The records of patients with listeriosis in mainland China reported during the years 2011–2017 were extracted. The clinical data of patients and information on clinical isolates of Listeria were collected and analyzed. In total, 136 records were identified, reporting 562 patients with listeriosis. The number of patients was much higher than that reported in the previous decade. The 227 non-perinatal listeriosis patients included had a mortality rate of 23.78%. Of the 231 perinatal listeriosis patients, 32.68% resulted in abortion and/or newborn death. All listeriosis cases were reported as being sporadic. The listeriosis was traced to infection via a meat product in only three patients, while 33.12% were healthcare-associated infections. The number of patients with listeriosis in mainland China may have been underestimated previously. Perinatal cases in mainland China account for a much higher proportion than is usually described. Considering the high number of listeriosis patients in China, a comprehensive monitoring system for Listeria is urgently needed. [ABSTRACT FROM AUTHOR]

Objectives: This qualitative study aimed to explore the factors influencing the prescription patterns of essential medicines (EMs) from the perspectives of general practitioners (GPs) and patients in Beijing, China., Design: The qualitative study was conducted using individual in-depth interviews., Setting: This study was conducted from January to August 2020, in community health service centres (CHSCs) across six urban districts of Beijing, China., Participants: A total of 17 GPs from 17 CHSCs in 6 urban districts and 22 patients with non-communicable diseases from three CHSCs in the three urban districts of Beijing were recruited using the purposive sampling method and a three-stage sampling strategy, respectively., Results: Five major themes were identified among factors influencing the prescription pattern of EMs: (1) efficacy and safety of medicines, (2) prescription recommendations from physicians in tertiary or secondary hospitals, (3) patients' medication preference, (4) financial status of patients and (5) minimum requirement for the prescription of EMs., Conclusion: The findings of this study contribute to our understanding of the factors influencing the prescription patterns and utilisation of EMs from the perspectives of GPs and patients, respectively. Policymakers should implement policies and measures to promote the National Essential Medicines System in China., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Although combination antiretroviral therapy (cART) including tenofovir (TDF)+lamivudine (3TC) or emtricitabine (FTC) is recommended for treatment of HIV/HBV coinfected patients, TDF is unavailable in some resource-limited areas. Some data suggest that 3TC monotherapy-based cART may be effective in patients with low pretreatment HBV DNA., Methods: Prospective study of 151 Chinese HIV/HBV coinfected subjects of whom 60 received 3TC-based cART and 91 received TDF+3TC-based cART. Factors associated with HBV DNA suppression at 24 and 48 weeks, including anti-HBV drugs, baseline HBV DNA, and baseline CD4 cell count, were evaluated overall and stratified by baseline HBV DNA using Poisson regression with a robust error variance., Results: Baseline HBV DNA ≥20,000 IU/mL was present in 48.3% and 44.0% of subjects in the 3TC and TDF groups, respectively (P = 0.60). After 48 weeks of treatment, HBV DNA suppression rates were similar between these 2 groups (96.8% vs. 98.0% for 3TC and TDF+3TC, P > 0.999) in subjects with baseline HBV DNA <20,000 IU/mL; whereas in those with baseline HBV DNA ≥20,000 IU/mL, TDF+3TC was associated with higher suppression rates (34.5% vs. 72.5% in 3TC and TDF+3TC groups, respectively, P = 0.002). In stratified multivariate regression, TDF use (RR 1.98, P = 0.010) and baseline HBV DNA (per 1 log increase in International Units Per Milliliter, RR 0.74, P < 0.001) were associated with HBV DNA suppression only when baseline HBV DNA ≥20,000 IU/mL., Conclusion: This study suggests that 3TC monotherapy-based cART is efficacious for HBV treatment through 48 weeks in HIV/HBV coinfection when baseline HBV DNA <20,000 IU/mL. Studies with long-term follow-up are warranted to determine if this finding persists.

HIV increases the risk of liver disease as do two common coinfections, hepatitis B and C viruses (HBV and HCV). However, whether combination antiretroviral therapy (cART) reverses or exacerbates hepatic fibrosis remains unclear.This was an observational retrospective study. cART-naïve HIV-infected subjects without a history of substance abuse (including alcohol) had liver disease stage determined by aspartate aminotransferase-to-platelet ratio indices (APRIs) and fibrosis-4 (FIB-4) before and 24 and 48 weeks after cART. All the data were retrieved from previously established cohorts. Values before and after cART were compared using Wilcoxon test for paired samples. Regression analyses were used to determine factors associated with moderate-to-severe liver disease.Of the 1105 HIV-infected subjects, 120 were HBV coinfected and 64 were HCV coinfected. About 20% of HIV monoinfected participants had APRI and FIB-4 scores consistent with moderate-to-significant fibrosis compared to ∼36% of HIV-HBV coinfected and 67% to 77% of HIV-HCV coinfected participants. In adjusted analyses compared with HIV monoinfection, HBV coinfection was associated with 1.18-fold higher APRI (P < 0.001) and a 1.12-fold higher FIB-4 (P = 0.007) prior to cART; while HCV coinfection was associated with 1.94-fold higher APRI (P < 0.001) and a 1.43-fold higher FIB-4 (P < 0.001). After 48 weeks of cART, both fibrosis scores decreased in all subjects; however, HCV coinfection was still associated with higher fibrosis scores at week 48 compared to HIV monoinfection.cART was associated with improvement in hepatic fibrosis scores in the majority of HIV-hepatitis coinfected and HIV-monoinfected Chinese participants.

Background: Distribution of HIV-1 subtypes, transmitted drug resistance (TDR)/drug resistance mutation (DRM), and their impact on response to combination antiretroviral therapy remain poorly understood in China., Methods: We analyzed data from our multicenter cohort study with 444 antiretroviral-naive participants recruited between 2008 and 2010. HIV-1 subtype and tropism were determined by V3 sequencing, and TDR/DRM was determined by Pol sequencing. Virologic and immunologic responses were monitored over 96 weeks of follow-up. The initial combination antiretroviral therapy regimen for all patients was nevirapine + lamivudine + zidovudine or stavudine. Analysis 1 included patients who finished 96 weeks of follow-up (n = 379), and analysis 2 included all 444 patients., Results: Subtype B/B' was associated with higher prevalence of TDR/DRM to nucleoside reverse transcriptase inhibitors and nonnucleoside reverse transcriptase inhibitors. Median time to HIV-1 suppression was 18 weeks in all 3 subtype groups. In Cox proportional models for viral suppression, neither viral tropism nor HIV-1 subtypes had any impact on viral suppression; however, subtypes CRF01&#95;AE and C/CRF07&#95;BC/CRF08&#95;BC were associated with lower risk of virologic failure compared with subtype B/B', with adjusted hazard ratio of 0.11 (P = 0.032) and 0.06 (P = 0.036), respectively in analysis 1, 0.42 (P = 0.047) and 0.22 (P = 0.008), respectively in analysis 2. This association was attenuated by adding DRM profiles to multivariate regression models. Neither subtype nor HIV-1 tropism affected immunologic response., Conclusions: HIV-1 subtype tended to be associated with virologic but not immunologic response; this effect could be ascribed to baseline DRM.

Background: As life expectancy increases, HIV-infected patients are facing a wide array of metabolic complications, including diabetes mellitus (DM) and impaired fasting glucose (IFG). However, little is known about the incidence of and risk factors for glycemic disorders in Chinese HIV-infected patients., Methods: Longitudinal data were pooled from a multicenter clinical trial of combination antiretroviral regimens between 2009 and 2010 across Mainland China. DM was defined as fasting glucose level ≥7.0 mmol/L and IFG as between 5.6 and 6.9 mmol/L on 2 separate measurements. We calculated the incidence densities of DM and IFG. Risk factors for DM and IFG were also identified., Results: Four hundred fifteen patients contributed 457.35 person-years of follow-up. The incidence densities of DM and IFG were 2.62 and 35.64 per 100 person-years, respectively. In a multivariate analysis, advanced age [adjusted hazard ratio (HR): 1.03, 95% confidence interval (CI): 1.01 to 1.04], hepatitis B virus coinfection (adjusted HR: 1.59, 95% CI: 1.06 to 2.38), and baseline fasting glucose (adjusted HR: 1.28, 95% CI: 1.00 to 1.63) were associated with DM and IFG., Conclusions: A high incidence of DM and IFG was detected in Chinese HIV-infected patients receiving combination antiretroviral therapy. Clinicians should be aware of the potential for an increased risk of glycemic disorders in Chinese HIV-infected patients, particularly those of advanced age, with hepatitis B virus coinfection or high baseline fasting glucose.

A novel CC chemokine gene, chemokine CC motif ligand 4 (CCL4), was isolated from Megalobrama amblycephala. The full-length cDNA was 913 bp, encoding 94 amino acid residues. The deduced amino acid sequence possessed the typical arrangement of four cysteines as found in other known CC chemokines. The expression of M. amblycephala CCL4 during the early development showed the mRNA levels before hatching and at 62 h post fertilized (hpf) were significantly higher than other post-hatching stages (P < 0.05). Besides, it was widely expressed in all detected tissues with the highest transcription in liver, followed by intestine, spleen and gill, where a larger number of immune cells including lymphocytes and macrophages are present. Our findings had fully confirmed that CCL4 expression was strongly induced in vitro and quickly up-regulated after nitrite stress, then substantially altered in all tested tissues, supporting a potential pro-inflammatory function. We also indicated that inflammation effect might firstly happen in blood after nitrite stress. Furthermore, the tissue expression differences of CCL4 among three natural populations revealed that CCL4 mRNA in Yuni Lake population was obviously higher than the other two populations, Liangzi Lake population and Poyang Lake population, which will provide valuable insights into breeding strategies for selecting population with better immune property of M. amblycephala., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Background: The molecular epidemiology of the HIV-1 CRF01&#95;AE subtype as a risk factor for fast HIV-1 progression remains poorly understood., Methods: We analyzed HIV-1 tropism by utilizing samples from 201 treatment-naive patients in our multicenter cohort (12 research centers in different provinces of China). Tropism was determined by V3 loop sequencing. Data from 235 treatment-naive patients infected sexually (including aforementioned 201 patients) in this cohort with date of estimated seroconversion (EDS) were retrospectively evaluated. Median time from EDS to AIDS was analyzed by Kaplan-Meier curves. Hazard ratios were determined by Cox proportional model., Results: CRF01&#95;AE subtype was predominant (46.0%), especially in the MSM group. Further analysis revealed that the proportion of X4 tropism was higher in the CRF01&#95;AE subtype (45.5%) than in others (C/CRF07&#95;BC/CRF08&#95;BC, 4.3%; B, 6.1%; P <0.001). CRF01&#95;AE subtype was associated with faster progression from EDS to AIDS (4.8 vs. 6.4 years, P = 0.018) compared with non-CRF01&#95;AE subtypes. In a multivariate model, the adjusted hazard ratio (aHR) of CRF01&#95;AE was 1.42 (95% confidence interval, CI 0.99-2.03, P = 0.057), independent of HIV-1 viral load; it was also associated with fast progression to advanced immunodeficiency (aHR, 1.81, 95% CI 1.03-3.18, P = 0.038)., Conclusion: CRF01&#95;AE, a predominant HIV-1 subtype in Chinese HIV-1 sexually infected patients, tends to be associated with fast progression to AIDS and advanced immunodeficiency, which might be ascribed to high proportion of X4 tropism. Further investigation of these risk factors may have significant implications to clinical practice and policy-making.