Long-term effect of antiretroviral therapy on mortality among HIV-positive children and adolescents in China.

Introduction: Highly active antiretroviral therapy (HAART) was piloted in 2002 and was scaled up in 2003 in mainland China. The aim of this study was to evaluate the mortality and its possible predictors based on the long-term initial antiretroviral therapy (ART) cohort among HIV positive children and adolescents. Methods: This prospective open-labeled multicenter cohort study was conducted from January 2008 to July 2021. The participants were recruited from six representative sites in mainland China. A total of 609 participants with an HIV-positive serostatus and <18 years old were recruited and each participant was informed consent at the time of enrollment. Mortality and annual hazard were calculated, and predictors for death were analyzed using Cox regression models generating hazard ratios (HR). Results: The results showed that the mortality was 0.721 per hundred person-years, and the annual hazard was less than 0.10 over time. Both CD4+T cell count and CD4+T cell percentage declined in the death group during the follow-up. The Cox regression model showed that the baseline low CD4+T cell count level (Low vs. High: aHR = 8.309, 95% CI: (1.093, 63.135)) and age >5 years old at HIV diagnosis (6-12 vs. 0-5: aHR = 3.140, 95%CI: (1.331, 27.411)); 13-18 vs. 0-5: aHR = 5.451, 95%CI: (1.434, 20.724)) were possible risk factors for death. Conclusion: The longitudinal cohort study demonstrated the efficacy of China's ART program among HIV-positive children and adolescents which could be beneficial to other countries with limited resources.

Toxoplasma gondii seropositivity and cognitive functioning in older adults: an analysis of cross-sectional data of the National Health and Nutrition Examination Survey 2011-2014.

OBJECTIVES: This study sought to examine the relationship between Toxoplasma gondii seropositivity and cognitive function in older adults. DESIGN: An observational cross-sectional study. SETTING: The National Health and Nutrition Examination Survey (NHANES) study took place at participants' homes and mobile examination centres. PARTICIPANTS: A total of 2956 older adults aged 60 and above from the NHANES from 2011 to 2014 were included in the study. Exposure of interest: participants had serum Toxoplasma gondii antibody analysed in the laboratory. A value>33 IU/mL was categorised as seropositive for Toxoplasma gondii infection; <27 IU/mL was categorised as seronegative for Toxoplasma gondii infection. PRIMARY AND SECONDARY OUTCOME MEASURES: Cognitive tests included the Consortium to Establish a Registry for Alzheimer's Disease Word Learning subtest (CERAD-WL) for immediate and delayed memory, the Animal Fluency Test (AFT), and the Digit Symbol Substitution Test (DSST). RESULTS: About half of the 2956 participants (mean age 70.0) were female (51.0%), non-Hispanic White (48.3%), and completed some college or above (48.3%). A total of 703 participants were positive for Toxoplasma gondii infection (23.8%). Adjusted linear regression showed that compared with participants with negative Toxoplasma gondii infection, those with positive Toxoplasma gondii infection had lower CERAD-WL immediate memory (beta (ß) -0.16, 95% CI -0.25 to -0.07), CERAD-WL delayed memory (ß -0.15, 95% CI -0.24 to -0.06), AFT (ß -0.15, 95% CI -0.24 to -0.06), DSST (ß -0.34, 95% CI -0.43 to -0.26), and global cognition (ß -0.24, 95% CI -0.32 to -0.16) z-scores after controlling for the covariates. CONCLUSIONS: Toxoplasma gondii seropositivity is associated with worse immediate and delayed verbal learning, language proficiency, executive functioning, processing speed, sustained attention, working memory, as well as global cognition in older adults. Public health measures aiming at preventing Toxoplasma gondii infection may help preserve cognitive functioning in older adults.

Elimination of methylmercury production potential in excessive sludge in wastewater treatment plants by sulfur addition.

Mercury ions (Hg(II)) in wastewater can accumulate and transform into the highly neurotoxic methylmercury (MeHg) in activated sludge. The release of MeHg can have severe environmental consequences, making the treatment of MeHg-contaminated sludge a pressing concern. In this study, we found that all the collected activated sludge samples, from different wastewater treatment plants in four cities, had the potential for Hg methylation. The Hg-methylating capacity reached a maximum level of 0.70-0.92 µg/g volatile suspended solids after 48 h of exposure to 5 µg/L Hg(II) and showed an average MeHg production rate of 4.8±0.5%. Accordingly, a sludge treatment method involving the addition of elemental sulfur (S0) for a short-term or long-term duration (3 or 180 days, respectively) was proposed. The results demonstrated that this treatment approach effectively mitigated and potentially eliminated MeHg formation by simultaneously reducing Hg bioavailability and Hg-methylating bioactivity. We found that bioavailable Hg(II) ions were converted to a secondary phase similar to insoluble HgS after S0 addition treatment, leading to a decrease in Hg bioavailability in sludge. The enhancement of Hg and extracellular polymeric substances (EPS) complexation via the increasing amount of thiol groups in EPS also reduced the Hg bioavailability after the long-term treatment. Furthermore, the long-term S0 addition significantly reduced the abundance of Hg-methylators with hgcA gene and promoted the growth of Hg-reducers with merA gene, which ensured the complete elimination of MeHg production potential of the excessive activated sludge. Our findings demonstrated that the proposed S0-addition sludge treatment is a promising and safe biotechnology for treating Hg-contaminated sludge. This approach has the potential to contribute significantly to the mitigation of MeHg pollution within environmental contexts.

Fluorescence-quenching mechanisms of novel isomorphic Zn/Cd coordination polymers for selective nitrobenzene detection.

Nitroaromatic compounds in aqueous undermine environmental sustainability and affect human health. The development of a fluorescent sensor capable of efficiently and selectively detecting trace amounts of nitroaromatic compounds presents a considerable challenge. This study introduced Zn/Cd isomeric coordination polymers (Zn-H2CIA-1/Cd-H2CIA-2), which are synthesized using 5-((4-carboxybenzyl)oxy)isophthalic acid (5-H3CIA) and 1,10-phenanthroline (Phen). The polymers have zero-dimensional discrete crystal structure with a six-coordinated scissor-like shape. The two coordination polymers can be used as fluorescent sensors for detecting nitrobenzene (NB) and demonstrated favorable sensitivity, with detection limits of 1.95 × 10-8 and 4.66 × 10-7 mol/L, respectively. Zn-H2CIA-1 exhibited stronger fluorescence and a more sensitive response to NB compared with Cd-H2CIA-2. To elucidate their fluorescence-quenching mechanisms, we analyzed Zn-H2CIA-1 by performing DFT and TD-DFT calculations. The pore structure, density of states, excitation energy, hole-electron distribution, and orbital composition were analyzed. The suitable size of pores in Zn-H2CIA-1 is the main reason for its high NB selectivity. Moreover, intermolecular π-π stacking interactions result in an orbital overlap between Zn-H2CIA-1 and NB, enabling the transfer of electrons from Zn-H2CIA-1 to NB. This electron transfer is identified as the fundamental cause of fluorescence quenching in Zn-H2CIA-1.

Increased prevalence of pretreatment drug resistance mutations in treatment-naïve people living with HIV-1 in Henan Province, China (2022/23).

Human deficiency virus type 1 (HIV-1) harboring drug resistance mutations (DRMs) before the initiation of antiretroviral therapy (ART) poses a serious threat to the efficacy of current ART regimens. Currently, the prevalence of pre-treatment drug resistance mutations (PDRMs) including transmitted DRMs (TDRMs) is not completely clear. Understanding this prevalence better should offer valuable data for clinical- and government-level decision-making. To closely monitor the PDRM trend in treatment-naïve people living with HIV/AIDS (PLWHA) in Henan Province, China, plasma samples from the patients seeking treatments at our hospital from January 2022 to February 2023 were collected for genotypic drug resistance testing. From the 645 patients whose samples were collected, partial pol and integrase gene sequences were obtained from 637 patients. Subtyping analysis indicated that the top-three most common subtypes, in descending order, were CRF07_BC (41.76%, 266/637), CRF01_AE (28.26%, 180/637), and B (20.41%, 130/637). PDRMs were observed in 5.18% (33/637), 6.28% (40/637), 0.31% (2/637), and 2.83% (18/637) cases for nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), protease inhibitors (PIs), and integrase strand transfer inhibitors (INSTIs), respectively; all these medications contributed to an overall PDRM prevalence of 11.93% (76/637). On analyzing individual PDRMs, we noted that the most commonly observed mutation(s) were K103S/N (3.77%, 24/637), M184I/V (3.14%, 20/637), followed by K65R (1.26%, 8/637), and V106A/M (1.10%, 7/637). PDRM prevalence in ART-naïve PLWHA of Henan Province is high and increased compared with that noted in previous years. However, evidence of cluster-linked outbreaks of PDRMs is lacking, suggesting that measures such as education about adherence and improved treatment strategies with a low incidence of failure can effectively reduce PDRM prevalence.

Efficacy and safety of ainuovirine versus efavirenz combination therapies with lamivudine/tenofovir disoproxil fumarate for medication of treatment-naïve HIV-1-positive adults: week 48 results of a randomized controlled phase 3 clinical trial followed by an open-label setting until week 96.

Background: Ainuovirine (ANV) is a new non-nucleoside reverse transcriptase inhibitor (NNRTI), which was initially synthesized in Korea and later further developed in both Korea and China. Methods: A randomized, double-blind, double-dummy, positive parallel group, non-inferiority, phase 3 trial was conducted in 7 sites across China. Eligible HIV-1-positive antiretroviral therapy (ART)-naïve adults aged 18-65 years were randomly assigned in a 1:1 ratio to receive tenofovir disoproxil fumarate and lamivudine (TDF+3TC) in combination with either ANV (ANV group) or efavirenz (EFV group) for up to 48 weeks. Subsequently, participants in both groups received one of the two drug combinations according to their choice until week 96 in an observational study under an open-label setting. The primary endpoint was the proportion of participants achieving HIV RNA <50 copies/mL at week 48, with non-inferiority pre-specified at a margin of 10%. The secondary efficacy endpoints were logarithmic changes in HIV RNA, percentage of participants with HIV RNA levels ≤400 copies/mL and changes in the CD4 T-cell count after 48 and 96 weeks of treatment, as well as the percentage of participants with HIV RNA levels <50 copies/mL at 96 weeks of treatment. Safety endpoints were the incidence of adverse events and laboratory abnormalities evaluated according to the Division of AIDS criteria. This study was registered with the Chinese Clinical Trial Registry (Registration number: ChiCTR1800019041). Findings: Between November 27, 2018 and March 11, 2021, a total of 826 participants were screened, and 630 were finally enrolled and randomly assigned (1:1) to either ANV (n = 315) or EFV (n = 315) groups. The mean age was 30.6 ± 9.4 years and most participants were male (94.6%). At week 48, 274 (87.0%) of 315 participants in the ANV group and 288 (91.7%) of 314 in the EFV group achieved HIV-1 RNA <50 copies/mL and non-inferiority was established (difference: -4.7%, 95% CI: -9.6 to 0.1%). In the period, 293 participants continued to take the ANV regimen and 287 switched from the EFV to the ANV regimen. During the open-label period, 92.5% (271/293) of participants in the continued ANV group and 95.1% (273/287) in the ANV to EFV transfer group remained virologically suppressed (HIV-1 RNA <50 copies/mL) at week 96 (p = 0.189). The incidence of NNRTI treatment-related adverse events (TEAEs) at week 48 was 67.6% in 315 participants in the ANV group, which was significantly lower than in 91.4% of 314 participants in the EFV group (p < 0.001). The most common TEAEs (weeks 0-48) were dizziness (10.5%) and dyslipidemia (22.2%) in the ANV group vs. 51.0% and 34.4% in the EFV group, respectively, followed by transaminase elevation (9.2% vs. 29.0%), γ-glutamyl transferase elevation (8.3% vs. 19.1%), and rash (7.9% vs. 18.8%) (all p < 0.001). After switching from EFV to ANV, TEAEs in the former EFV participants were significantly reduced in the following observational period of 48-96 weeks. Interpretation: The week 48 results indicated that the efficacy of ANV was non-inferior to EFV when combined with two NRTIs. The per-protocol risk difference at week 48 for the primary endpoint also supported non-inferiority. TEAEs in ANV treated participants were less frequent with regard to liver toxicity, dyslipidemia, neuropsychiatric symptoms and rash compared to the EFV group during the first 48 weeks of therapy. The effects were maintained during the 48-96 weeks of therapy. Funding: Jiangsu Aidea Pharmaceutical Co., Ltd.

Pattern of infection and genotypes of human papillomavirus in Zhengzhou City based on a four-year (2015-2018) epidemiological study.

Persistent human papillomavirus (HPV) infection has been associated with the development of cervical cancer. To reduce the incidence of cervical cancer and promote awareness of HPV, a government-sponsored epidemiological study was conducted from 2015 to 2018 in Zhengzhou City. A total of 184,092 women aged 25-64 years were included, of which 19,579 were infected with HPV, reflecting a prevalence of 10.64 percent (19,579/184,092). The HPV genotypes found were classified as high-risk (13 genotypes) and low-risk (8 genotypes). Single and multiple infections were detected in 13,787 (70.42 percent) and 5,792 (29.58 percent) women, respectively. The five most common high-risk genotypes detected, listed in descending order, were HPV52 (2.14 percent; 3,931/184,092), HPV16 (2.04 percent; 3,756/184,092), HPV58 (1.42 percent; 2,607/184,092), HPV56 (1.01 percent; 1,858/184,092), and HPV39 (0.81 percent; 1,491/184,092). Meanwhile, the most common low-risk genotype was HPV53 (0.88 percent; 1,625/184,092). The prevalence of HPV gradually increased with age, with the highest occurring in women aged 55-64 years. The prevalence of single-type HPV infection decreased with age, whereas that of multiple-type HPV infection increased with age. This study indicates a high burden of HPV infection in women in Zhengzhou City.

Microbial cell wall sorption and Fe-Mn binding in rhizosphere contribute to the obstruction of cadmium from soil to rice.

Screening high-tolerant microorganisms to cadmium (Cd) and revealing their bio-obstruction mechanism could be significant for Cd regulation from farmland to the food chain. We examined the tolerance and bio-removal efficiency of Cd ions of two bacterial strains, Pseudomonas putida 23483 and Bacillus sp. GY16, and measured the accumulation of Cd ions in rice tissues and its different chemical forms in soil. The results showed that the two strains had high tolerance to Cd, but the removal efficiency was decreased successively with increasing Cd concentrations (0.05 to 5 mg kg-1). Cell-sorption accounted for the major proportion of Cd removal compared with excreta binding in both strains, which was conformed to the pseudo-second-order kinetics. At the subcellular level, Cd was mostly taken up by the cell mantle and cell wall, and only a small amount entered into the cytomembrane and cytoplasmic with time progressed (0 to 24 h) in each concentration. The cell mantle and cell wall sorption decreased with increasing Cd concentration, especially in the cytomembrane and cytoplasmic. The scanning electron microscope (SEM) and energy dispersive X-ray (EDS) analysis verified that Cd ions were attached to the cell surface, and the functional groups of C-H, C-N, C=O, N-H, and O-H in the cell surface may participate in cell-sorption process tested by the FTIR analysis. Furthermore, inoculation of the two strains significantly decreased Cd accumulation in rice straw and grain but increased in the root, increased Cd enrichment ratio in root from soil, decreased Cd translocation ratio from root to straw and grain, and increased the Cd concentrations of Fe-Mn binding form and residual form in rhizosphere soil. This study highlights that the two strains mainly removed Cd ions in solution through biosorption and passivated soil Cd as Fe-Mn combined form ascribe to its characteristics of manganese-oxidizing, eventually achieving bio-obstruction of Cd from soil to rice grain.

The high fluorescence sensitivity property and quenching mechanism of one-dimensional Cd-HCIA-1 sensor for nitrobenzene.

The sensing of nitroaromatic compounds in aqueous solution is closely related to environmental sustainability and human health. In this study, a novel Cd(II) coordination polymer (Cd-HCIA-1) was designed and prepared, and its crystal structure, luminescence performance, detection of nitro pollutants in water, and fluorescence quenching mechanisms were studied. Cd-HCIA-1 exhibited a one-dimensional ladder-like chain based on a T-shape ligand of 5-((4-carboxybenzyl) oxy) isophthalic acid (5-H3CIA). The H-bonds and π-π stacking interactions were then used to construct the supramolecular skeleton in common. Luminescence studies revealed that Cd-HCIA-1 can detect nitrobenzene (NB) in aqueous solution with high sensitivity and selectivity, and the limit of detection was 3.03 × 10-9 mol L-1. The fluorescence quenching mechanism of the photo-induced electron transfer for NB by Cd-HCIA-1 was obtained through an investigation of the pore structure, density of states, excitation energy, orbital interactions, hole-electron analysis, charge transfer, and electron transfer spectra by using density functional theory (DFT) and time-dependent DFT methods. NB was absorbed in the pore, π-π stacking increased the orbital overlap, and the LUMO was mainly composed of NB fragments. The charge transfer between ligands was blocked, resulting in fluorescence quenching. This study on fluorescence quenching mechanisms can be used to develop efficient explosive sensors.

Pyruvate dehydrogenase kinase supports macrophage NLRP3 inflammasome activation during acute inflammation.

Activating the macrophage NLRP3 inflammasome can promote excessive inflammation with severe cell and tissue damage and organ dysfunction. Here, we show that pharmacological or genetic inhibition of pyruvate dehydrogenase kinase (PDHK) significantly attenuates NLRP3 inflammasome activation in murine and human macrophages and septic mice by lowering caspase-1 cleavage and interleukin-1ß (IL-1ß) secretion. Inhibiting PDHK reverses NLRP3 inflammasome-induced metabolic reprogramming, enhances autophagy, promotes mitochondrial fusion over fission, preserves crista ultrastructure, and attenuates mitochondrial reactive oxygen species (ROS) production. The suppressive effect of PDHK inhibition on the NLRP3 inflammasome is independent of its canonical role as a pyruvate dehydrogenase regulator. Our study suggests a non-canonical role of mitochondrial PDHK in promoting mitochondrial stress and supporting NLRP3 inflammasome activation during acute inflammation.

Treatment and remediation of metal-contaminated water and groundwater in mining areas by biological sulfidogenic processes: A review.

Heavy metal pollution in the mining areas leads to serious environmental problems. The biological sulfidogenic process (BSP) mediated by sulfidogenic bacteria has been considered an attractive technology for the treatment and remediation of metal-contaminated water and groundwater. Notwithstanding, BSP driven by different sulfidogenic bacteria could affect the efficiency and cost-effectiveness of the treatment performance in practical applications, such as the microbial intolerance of pH and metal ions, the formation of toxic byproducts, and the consumption of organic electron donors. Sulfur-reducing bacteria (S0RB)-driven BSP has been demonstrated to be a promising alternative to the commonly used sulfate-reducing bacteria (SRB)-driven BSP for treating metal-contaminated wastewater and groundwater, due to the cost-saving in chemical addition, the high efficiency in sulfide production and metal removal efficiency. Although the S0RB-driven BSP has been developed and applied for decades, the present review works mainly focus on the developments in SRB-driven BSP for the treatment and remediation of metal-contaminated wastewater and groundwater. Accordingly, a comprehensive review for metal-contaminated wastewater treatment and groundwater remediation should be provided with the incorporation of the SRB- and S0RB-driven BSP. To identify the bottlenecks and to improve BSP performance, this paper reviews sulfidogenic bacteria presenting in metal-contaminated water and groundwater; highlight the critical factors for the metabolism of sulfidogenic bacteria during BSP; the ecological roles of sulfidogenic bacteria and the mechanisms of metal removal by sulfidogenic bacteria; and the application of the present sulfidogenic systems and their drawbacks. Accordingly, the research knowledge gaps, current process limitations, and future prospects were provided for improving the performance of BSP in the treatment and remediation of metal-contaminated wastewater and groundwater in mining areas.

Thirteen-year viral suppression and immunologic recovery of LPV/r-based regimens in pediatric HIV treatment: a multicenter cohort study in resource-constrained settings of China.

Background: Antiretroviral Therapy (ART) in children remains challenging due to resource-constrained settings. We conducted a 13-year, prospective, multicenter cohort study on the effectiveness and safety of LPV/r-based regimens in ART-naive and ART-experienced children. Methods: From January 2008 to May 2021, children living with HIV-1 were recruited with LPV/r-based regimens from 8 clinical research sites in 6 provinces in China. Effectiveness outcomes were virologic failure (defined as at least two consecutive measurements of VL > 200 copies/mL after 6 months of ART) and immune response (defined as CD4% recovered to more than 25% after 12 months of treatment). The safety outcomes were treatment-related grade 2-4 adverse events and abnormal laboratory test results. Results: A total of 345 ART-naïve children and 113 ART-experienced children were included in this cohort study. The median follow-up time was 7.3 (IQR 5.5-10.5) years. The incidence density of virologic failure was 4.1 (95% CI 3.3-4.9) per 100 person-years in ART-naïve children and 5.0 (95% CI 3.5-6.5) per 100 person-years in ART-experienced children. Kaplan Meyer (KM) curve analysis showed children with ART experience were at a higher risk of virologic failure (p < 0.05). The risk factors of virologic failure in ART-naïve children were clinic setting in rural hospitals (aHR = 2.251, 1.108-4.575), annual missed dose times >5 days of LPV intake (aHR = 1.889, 1.004-3.554); The risk factor of virologic failure in ART-experienced children was missed dose times >5 days (aHR = 2.689, 1.299-5.604) and mother as caregivers for ART administration (aHR = 0.475, 0.238-0.948). However, during long-term treatment, viral suppression rates between ART-naïve and ART-experienced children remained similar. No significant differences were observed in the immune response, treatment-related grade 2-4 events, and abnormal laboratory test results between ART-naïve children and ART-experienced children. Conclusion: Our research underscores that with consistent, long-term treatment of LPV/r-based regimens, ART-experienced children can achieve therapeutic outcomes comparable to ART-naïve children. It provides crucial insights on LPV/r-based regimens in pediatric HIV treatment, especially in resource-limited settings where high-cost Integrase Strand Transfer Inhibitors (INSTs) are inaccessible. This evidence-based understanding provides an essential addition to the global therapeutic strategies for pediatric HIV treatment.

Consistency of drug-resistant mutations in plasma and peripheral blood mononuclear cells of patients with treatment-naïve and treatment-experienced HIV-1 infection.

Introduction: Genotypic drug resistance testing is cursrently recommended by the World Health Organization for all patients infected with human immunodeficiency virus type 1 (HIV-1) undergoing care or switching regimes due to failure with previous antiretroviral therapy (ART). Patients with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) who meet the criteria for free testing for genotypic drug resistance due to poor adherence in Henan Province may resume their previous regimens before resampling. Therefore, resistance testing based on plasma RNA can fail in a proportion of patients. Resistance testing based on peripheral blood mononuclear cells (PBMCs) is an alternative option. In this study, we investigated the differences in drug-resistant mutations (DRMs) between plasma HIV RNA and proviral DNA in treatment-experienced and treatment-naïve patients. Methods: Matched plasma RNA and proviral DNA samples of 66 HIV-1 infected treatment-naïve and 78 treatment-experienced patients were selected for DRM analysis and comparison. Results: DRMs were detected in 27.3% (18/66) of treatment-naïve and 80.8% (63/78) of treatment-experienced samples. Resistance to at least one drug was detected based on analysis of plasma RNA and proviral DNA in 7.6% (5/66) and 9.1% (6/66) of treatment-naïve patients and in 79.5% (62/78) and 78.2% (61/78) of treatment-experienced patients, respectively. Furthermore, 61/66 (92.4%) of treatment-naïve patients showed concordant RNA and DNA drug resistance. When drug resistance was defined as intermediate and high, the concordance of drug resistance profiles of paired RNA and proviral DNA samples derived from treatment-naïve patients were up to 97.0% compared with only 80.8% (63/78) in treatment-experienced patients. Discussion: Our data indicate that drug resistance testing based on plasma RNA or proviral DNA might be interchangeable in treatment-naïve patients, whereas plasma RNA-based testing remains the best choice for drug resistance analysis in patients with ART failure in clinical practice.

Effects of Radiant Floor Heating Integrated with Natural Ventilation on Flow and Dispersion in a Newly Decorated Residence.

To date, few studies have been conducted on the characteristics of flow and dispersion caused by indoor radiant floor heating integrated with natural ventilation. In this study, we employed reduced-scale numerical models validated by wind-tunnel experiments to investigate the influence of radiant floor heating integrated with natural ventilation on airflow, heat transfer, and pollutant dispersion within an isolated building. The Richardson number (Ri) was specified to characterize the interaction between the inflow inertia force and the buoyancy force caused by radiant floor heating. Several Ri cases from 0 to 26.65, coupled with cross- or single-sided ventilation, were considered. Model validation showed that the numerical model coupled with the RNG k-ε model was able to better predict the indoor buoyant flow and pollutant dispersion. The results showed that the similarity criterion of Ri equality should be first satisfied in order to study indoor mixed convection using the reduced-scale model, followed by Re-independence. For cross-ventilation, when Ri < 5.31, the incoming flow inertia force mainly dominates the indoor flow structure so that the ACH, indoor temperature, and pollutant distributions remain almost constant. When Ri > 5.31, the thermal buoyancy force becomes increasingly important, causing significant changes in indoor flow structures. However, for single-sided ventilation, when Ri > 5.31 and continues to increase, the buoyancy force mainly dominates the indoor flow structure, causing a significant increase in ACH, thus reducing the indoor average temperature and pollutant accumulation.

Sarcoptic mange is an emerging threat to biodiversity in the Qinling Mountains in China.

Sarcoptic mange, a disease caused by the burrowing mite Sarcoptes scabiei, is globally endemic and an emerging threat to wildlife. Although many studies have shown that wildlife diseases play key roles in biodiversity conservation, knowledge about sarcoptic mange is still insufficient. In this study, we aim to improve the understanding of the impacts of sarcoptic mange on wildlife populations, the mechanisms involved in its eco-epidemiology and the associated risks to public and ecosystem health by investigating mass death events in gorals and serows in the Qinling Mountains. We conducted interviews with practitioners and local people in the central Qinling Mountains. From the same locations, we collected 24 cutaneous samples from various animals and surveillance data from infrared cameras. Pathological, parasitological and microbiological examinations of the samples were performed. Mite-induced cutaneous lesions, mites and eggs were observed in samples from dead gorals and one dead serow but not in other species. Molecular analysis confirmed the mites to be S. scabiei and shared the same cox 1 genotype. The data obtained from the interviews and infrared cameras indicated that the death of wildlife was related to sarcoptic mange infection and that there had been a decrease in the goral population since the outbreak of the disease. We confirmed that sarcoptic mange was the major cause of the mass death events and may have spread from the western to eastern Qinling Mountains. Based on our findings, we propose several protection strategies to help preserve biodiversity in the Qinling Mountains.

Sequence addition to the N- or C-terminus of the major capsid protein VP1 of norovirus affects its cleavage and assembly into virus-like particles.

Norovirus (NoV) infection is a leading cause of non-bacterial gastroenteritis worldwide and there are currently no effective therapeutics available to target the virus. The norovirus major capsid protein VP1 is a potential candidate for the development of vaccines due to the similar morphology and immunogenicity of its assembled virus-like particles (VLPs) compared to native virions. In this study, we explored the effects of N- and C-terminal sequence additions to the VP1 of a GII.4 NoV during its assembly into VLPs. A series of sequences of different lengths derived from the minor capsid protein VP2 of the GII.4 NoV were added to the N- and C-terminus of VP1. The fusion proteins were expressed using a recombinant baculovirus expression system and the assembly of the expressed fusion proteins was subsequently observed under electron microscopy (EM). Our results indicated that all constructed fusion proteins were successfully expressed with different degrees of enzyme cleavage at the N-terminus. Electron microscopy revealed the successful assembly of VLPs of different sizes for all fusion proteins. An in vitro binding assay for VLP-histo-blood group antigens (HBGAs) indicated that all fusion proteins exhibited similar binding patterns compared with their wild-type VP1. Our results demonstrate that (Xi et al., 1990) [1] NoV VP1 can tolerate foreign sequences at its N- or C-terminus without affecting its ability to assemble into VLPs, and (Jiang et al., 1992) [2] that the cleavage pattern and effects of foreign sequences on the sizes of assembled VLPs observed in this study might represent important experimental data that can be used to elucidate VP1 self-assembly.

Expression of chimeric proteins based on a backbone of the GII.4 norovirus VP1 and their application in the study of a GII.6 norovirus-specific blockade epitope.

The surface-exposed loop regions of the protruding domain of the norovirus (NoV) major capsid protein VP1 can tolerate the insertion of foreign antigens without affecting its assembly into subviral particles. In this study, we investigated the tolerance of the surface-exposed loop region of the GII.4 NoV VP1 by replacing it with homologous or heterologous sequences. We designed a panel of constructs in which the amino acid sequence from position 298-305 of the GII.4 NoV VP1 was replaced by sequences derived from the same region of GI.3, GII.3, GII.6, and GII.17 NoVs as well as neutralizing epitopes of enterovirus type 71 and varicella-zoster virus. The constructs were synthesized and expressed using a recombinant baculovirus expression system. The expression of target proteins was measured by indirect enzyme-linked immunosorbent assay (ELISA), and the assembly of virus-like particles (VLPs) was confirmed by electron microscopy. Our results showed that all of the constructs expressed high levels of target chimeric proteins, and all of the chimeric proteins successfully assembled into VLPs or subviral particles. An in vitro VLP-histo-blood group antigen (HBGA) binding assay revealed that chimeric-protein-containing VLPs did not bind or showed reduced binding to salivary HBGAs, a ligand for NoV particles. The results of an in vitro VLP-HBGA binding blockade assay indicated that the predicted surface-exposed loop region of the GII.6 NoV VP1 may comprise a blockade epitope. In summary, the surface-exposed loop region of the GII.4 NoV VP1 can be replaced by foreign sequences of a certain length. Using this strategy, we found that the predicted surface-exposed loop region of GII.6 NoV VP1 might contain a blockade epitope.