It remains unclear whether breastfeeding in infancy is associated with risk of metabolic dysfunction-associated steatohepatitis (MASH) and adverse liver outcomes in adulthood. We analyzed data from the prospective UK Biobank. Breastfeeding in infancy was ascertained via self-report. In a cross‑sectional analysis involving 26,850 participants with liver MRI data, metabolic dysfunction-associated steatotic liver disease (MASLD) was defined as PDFF > 5.5

OBJECTIVE:This study aims to systematically investigate the molecular epidemiology and genomic characteristics of Enterobacter cloacae complex (ECC) strains globally harbouring blaKPC and mcr, as well as the co-existence of drug resistance genes. The goal is to provide insights and recommendations for monitoring clinical drug-resistant strains and super-resistant plasmids. METHODS:This study analysed 281 ECC isolates harbouring both blaKPC and mcr, obtained from NCBI GenBank database (2003-2024) with whole-genome sequencing data. We constructed a phylogenetic tree of ECC strains for phylogenetic analysis. Resistance genes were identified using the ABRicate and CARD databases, and their distribution was examined. Plasmid replicon types for blaKPC and mcr were analysed with PlasmidFinder, including upstream and downstream genetic environments of these genes. RESULTS:The predominant genotype combinations harbouring both blaKPC and mcr are blaKPC-3 and mcr-9.1, followed by blaKPC-4 and mcr-9.1, with the dominant strain being E. hormaechei ssp. xiangfangensis. The IncHI2(2A) plasmid co-harbouring blaKPC and mcr-9 was mainly detected in genomes from the United States. Phylogenetic analysis indicated that the blaKPC-mcr-9-IncHI2(2A) plasmids in ECC strains have a high genetic similarity to mcr-9-IncHI2(2A), suggesting that the latter may have acquired the additional highly transferable blaKPC. CONCLUSIONS:ECC strains have become an important reservoir cluster for blaKPC and mcr-9, and the IncHI2(2A) plasmid is a potential vector for the horizontal co-transmission of carbapenem and colistin resistance genes. Effective monitoring should be implemented to assess the prevalence of co-harbouring blaKPC and mcr-9 in individual ECC isolates and even in single plasmid.

Background Although the majority of pregnancies with preeclampsia are characterised by elevated blood pressure, preeclampsia is often associated with nephrotic syndrome with similar symptoms such as high proteinuria and bilateral lower limb oedema. In this study, we compared the maternal–foetal outcomes of pregnant women with preeclampsia in a population with nephrotic syndrome and explored the factors that contribute to the corresponding outcomes and disease development. Methods A total of 90 pregnant women were included in this study, of whom 30 had nephrotic syndrome and were diagnosed with preeclampsia during pregnancy, and 60 had nephrotic syndrome alone. Descriptive statistical analyses of baseline data were performed to analyse the effect of combined preeclampsia on maternal and foetal pregnancy outcomes using unadjusted and adjusted logistic regression models. Results In this study, the baseline data of the two study populations demonstrated no differences except for the history of caesarean section and 24-h proteinuria results, which were significantly different ( P < 0.05). The risk of preterm birth in the nephrotic syndrome with preeclampsia group was 8.25 (95% CI:3.041–22.084 P < 0.05); for a low birth weight, the risk was 6.00 (95% CI:2.302–15.638 P < 0.05); for foetal distress,the risk was 5.667 (95% CI:2.070–15.514 P < 0.05); and the risk of foetal birth restriction was 7.429 (95% CI: 2.642–20.885 P < 0.05). A risk-based analysis of adverse maternal outcomes yielded a risk of miscarriage of 2.200 (95% CI: 0.584–8.291; P > 0.05). After adjusting the model for each outcome, significant risks of preterm labour, foetal birth restriction, and low birth weight were revealed ( P < 0.05). Conclusion Combined preeclampsia has a significantly higher risk of adverse pregnancy outcomes for the foetus.Therefore, the prevention and control of eclampsia in pregnant women should be improved to ensure maternal and neonatal health.

AIMS:To investigate the associations of conicity index (C-index) and relative fat mass (RFM) with incident type 2 diabetes mellitus (T2DM) among adults in China. MATERIALS AND METHODS:A total of 10 813 participants aged over 18 years in Shenzhen Longhua district were enrolled in a follow-up study conducted from 2018 to 2022. The participants were categorized based on quartiles (Q) of C-index and RFM. The Cox proportional hazards model was performed to examine the relationships between C-index, RFM and the risk of T2DM. RESULTS:After adjusting for potential confounding factors, including age, sex, occupation, marital status, education level, smoking status, alcohol consumption, physical exercise, hypertension status, fasting blood glucose (FBG) and total cholesterol (TC), both C-index and RFM showed positive and independent associations with risk of T2DM. The multivariable-adjusted hazard ratios (95% confidence intervals) for T2DM risk in participants in C-index Q3 and Q4 compared with those in C-index Q1 were 1.50 (1.12, 2.02) and 1.73 (1.29, 2.30), and 1.94 (1.44, 2.63), 3.18 (1.79, 5.64), 4.91 (2.68, 9.00) for participants in RFM Q2, Q3 and Q4 compared with RFM Q1. These differences were statistically significant (all p < 0.05). CONCLUSION:C-index and RFM are strongly associated with new-onset T2DM and could be used to identify the risk of diabetes in large-scale epidemiological studies.

目的:分析2型糖尿病(T2DM)住院患者心脏自主神经病变(CAN)的影响因素,探讨其对夜间无症状低血糖(AH)和夜间室性心律失常(VA)的影响.方法:选取2020年1月～2022年7月肇庆医学高等专科学校附属医院收治的174例T2DM患者,根据是否发生CAN分为CAN组和非CAN组,采用多因素Logistic回归分析T2DM住院患者CAN的影响因素.采用动态血糖监测系统监测夜间AH发生情况,动态心电图监测夜间VA发生情况.结果:174例T2DM患者CAN发生率为37.93％(66/174).单因素分析显示,CAN组年龄大于非CAN组,病程长于非CAN组,收缩压、舒张压、糖化血红蛋白(HbA1c)、稳态模型评估-胰岛素抵抗(HOMA-IR)、血尿酸和微血管并发症比例高于非CAN组(P＜0.05).多因素Logistic回归分析显示,年龄增加、病程延长、HOMA-IR升高、血尿酸升高、微血管并发症为T2DM住院患者CAN的独立危险因素(P＜0.05).与非CAN组比较,CAN组夜间AH、VA发生率增加(P＜0.05).结论:年龄、病程、HOMA-IR、血尿酸和微血管并发症为T2DM住院患者CAN的影响因素,CAN增加了 T2DM住院患者夜间AH和夜间VA的发生率,早期筛查CAN可能有助于降低T2DM住院患者夜间AH和夜间VA的发生风险.

Abstract Background Disease situations are more aggressive in patients with childhood-onset systemic lupus erythematosus (cSLE) than in those with adult-onset SLE (aSLE). However, information on pregnant women with cSLE and its association with pregnancy outcomes is limited. This study aimed to compare pregnancies in patients with cSLE vs. aSLE, and further analyse the characteristics of cSLE in pregnant women and explore its association with adverse pregnancy outcomes. Methods Altogether, data of 167 pregnancies from 150 women, including 22 pregnancies with cSLE and 145 pregnancies with aSLE, were retrospectively analysed. Characteristics and disease activity were compared between the cSLE and aSLE groups during pregnancy. Associations between cSLE and the risk of active SLE (SLEPDAI > 4), active lupus nephritis (LN), and adverse pregnancy outcomes were analysed using logistic regression. Results The cSLE group had a higher incidence of active SLE (12/22 vs. 30/145, P = 0.001) and active LN (11/22 vs. 26/145, P = 0.001) than the aSLE group. In the multivariable analysis, cSLE was a risk factor for active SLE and active LN during pregnancy, with ORs of 4.742 (95%CI 1.678–13.405, P = 0.003) and 4.652 (95%CI 1.630–13.279, P = 0.004), respectively. No significant association between cSLE and the risk of composite adverse gestational outcomes was identified after sequentially adjusting pre-pregnancy characteristics and pregnancy factors (P > 0.05). Conclusion Disease activity of women with cSLE in pregnancy was more aggressive than that of women with aSLE, which was similar to the characteristics of non-pregnant women with SLE. cSLE might have indirect effects on the risk of adverse pregnancy outcomes through LN and active disease. Therefore, closely monitoring patients with cSLE during pregnancy is crucial.

目的 探讨妊娠早期维生素D缺乏对妊娠期糖尿病(GDM)发生及妊娠结局的影响.方法 收集2018年1月至2019年12月在佛山市妇幼保健院进行产检的孕妇1,516例,均在妊娠11～14周检测血液总25(OH)D含量和血清Ca2+、Mg2+、碱性磷酸酶、孕妇骨密度值等其它实验室指标,在妊娠24～28周进行75?g葡萄糖耐量试验,共有264例孕妇诊断为GDM.根据年龄±3岁并按1:2的比例匹配了528例非GDM孕妇进行研究.应用配对二分类logistic回归分析孕早期维生素D缺乏与GDM发生的关系.应用非条件二分类logistic回归分析孕早期维生素D缺乏及GDM发生与妊娠结局的关系.结果 单因素及多因素logistic回归分析结果显示,维生素D缺乏[25(OH)D<50?nmol/L]与GDM发生无相关,且无统计学意义(P>0.05).在调整了潜在混杂因素后,妊娠早期维生素D缺乏的早产发生风险较高,OR值为2.124(95％CI:1.111～4.060,P=0.023).未发现妊娠早期维生素D缺乏与其他妊娠结局如胎儿窘迫、胎膜早破和低出生体重儿等有关.结论 妊娠早期维生素D缺乏可能增加早产发生的风险,定期检测维生素水平,指导维生素D缺乏孕妇积极补充维生素D,可以改善妊娠结局.

不同亚型和循环重组亚型(Circulating recombinant forms,CRFs)在同一人群中的传播往往导致独特重组型(Unique recombinant forms,URFs)的出现.在本研究中,我们发现了两条新的 HIV-1 CRF55_01B/CRF07_BC第二代重组体(Second-generation recombinant forms,SGRs),它们分别来自江门市的同性恋和异性恋群体.系统进化分析表明,JM.pj44和JM.pj64的近全长基因组(Near full-length genomes,NFLGs)均以CRF55_01B为骨架,插入了CRF07_BC的基因片段,但断点位置不同.将本研究发现的两种新的NFLGs与其他研究中发现的CRF55_01B/CRF07_BC SGRs进行比较,目前未发现有相同的CRF55_01B/CRF07_BC重组体.

为了了解境外输入的新型冠状病毒(SARS-CoV-2)变异株的分子特征,本研究对2021年6月深圳市一株从南非输入的SARS-CoV-2毒株进行了全基因组测序和序列分析.Illumina测序技术获得的SARS-CoV-2毒株基因组长度为29567nt.根据"Pango lineages"分型法,本研究测定的毒株属于C.1.2系,该谱系属世界卫生组织定义的监测变异株(Variants Under Monitoring,VUM)成员之一.与参考株 Wuhan-Hu-1(NC_045512.2)比较,本研究 C.1.2系毒株共出现了 58个核苷酸变异位点,其中56个变异位点位于编码区.氨基酸变异位点共有33个,氨基酸变异位点分布于6个开放阅读框,变异数由多到少依次为:S蛋白区12个,ORFlab蛋白区9个,ORF3a蛋白区2个,M区2个,ORF8区2个,E区1个.本研究测定的SARS-CoV-2毒株属我国大陆首例境外输入的C.1.2变异株.开展境外输入的SARS-CoV-2毒株基于基因组测序的分子监测,对防控由境外输入的SARS-CoV-2变异株引起本地新型冠状病毒肺炎(COVID-19)暴发与流行具有重要意义.

Background Norovirus (NoV) is the main cause of non-bacterial acute gastroenteritis (AGE) outbreaks worldwide. From September 2015 through August 2018, 203 NoV outbreaks with 2,500 patients were reported to the Shenzhen Center for Disease Control and Prevention. Methods Fecal specimens were collected from the 203 outbreaks and epidemiological data were collected through the AGE outbreak surveillance system in Shenzhen. The genotypes were determined by sequencing analysis. To gain a better understanding of evolutionary characterization of NoV in Shenzhen, the molecular evolution was analyzed by time-scale evolutionary phylogeny and amino acid mutations. Results Most of these outbreaks were associated with NoV GII.P16/GII.2 strain (45.3%,92/203) and occurred in school settings (91.6%,186/203). The timescale phylogeny suggested that the GII.P16/GII.2 strain was recombination strain and were still stable. The amino acid mutations suggested that the nonstructural proteins of the recombination strain might play a more significant role than VP1 gene in these GII.P16/GII.2 recombination strain outbreaks. Conclusions This study illustrated the characteristics of the molecular epidemiological patterns in Shenzhen, China during September 2015 to August 2018 and provided the evidence that the GII.P16/GII.2 strain was static and the epidemic trend had fade.

目的 探讨含糖饮料摄入与儿童青少年中心性肥胖的关系.方法 利用"中国健康与营养调查"项目公开数据库中1997-2011年的横断面调查数据,分析中国7～17岁儿童青少年含糖饮料摄入与中心性肥胖的关系.根据腰围划分为正常组和中心性肥胖前期/中心性肥胖组,采用x2检验比较不同组间差异,采用多因素Logistic回归分析模型分析含糖饮料对儿童青少年中心性肥胖的影响.结果 1916名7～17岁儿童青少年中,含糖饮料摄入频率≥3次/周、1～2次/周、1～3次/月和＜1次/月分别为389人(20.3％)、712人(37.2％)、563人(29.4％)和252人(13.2％).共计731例(38.2％)发生中心性肥胖前期/中心性肥胖,调整相关混杂因素后,与摄入含糖饮料＜1次/月组相比,≥3次/周组增加68.0％的肥胖风险(95％ CI:1.194～2.346,P=0.003);年龄、性别对含糖饮料摄入频率和中心性肥胖的关系无统计学影响.结论 含糖饮料摄入频率增高会增加儿童青少年中心性肥胖发生风险.

Jiangmen is one of the Guangdong‐Hong Kong‐Macao Greater Bay Areas with frequent commercial intercourse, which is responsible for human immunodeficiency virus type 1 (HIV‐1) rapid circulation and genetic evolution for recent years. As a novel HIV‐1 second‐generation recombinant was previously reported in Jiangmen but the systematic molecular epidemiological investigation was still unknown. A retrospective study on HIV‐1 genotypic characteristics and the emergence of transmitted drug resistance in this region was necessary. A total of 224 newly diagnosed HIV‐positive cases were randomly selected in Jiangmen City of Guangdong Province between 2018 and 2019. The partial gag (1080 bp), pol (840 bp), and env (460 bp) genes were amplified using nested polymerase chain reaction followed by sequencing. The phylogenetic and recombination analysis as well as HIV‐1 drug resistance were performed to surveillance. Sexual transmission was determined to be the major risk factor in Jiangmen. Phylogenetic analysis detected the genotypic distribution as follows: CRF01_AE (36.65%,70 of 191), CRF07_BC (32.46%, 62 of 191), CRF08_BC (4.71%, 9 of 191), CRF55_01B (5.24%, 10 of 191), CRF59_01B (3.14%, 6 of 191), subtype B (4.71%, 9 of 191), subtype C (1.05%, 2 of 191) as well as unique recombinant forms (12.04%, 23 of 191) consisted of seven recombinant patterns, which originated from multiple regions of China. Low‐level prevalence of Surveillance Drug Resistance Mutations (2.1%) were predicted but drug‐resistant mutations showed at a high level (15.4%) especially mutations in RT gene at position 179 were found to be the most frequent in the therapy‐naïve population. Our study highlighted the critical importance of monitoring the emerge of recombinant strains among newly diagnosed HIV‐1 individuals along with drug resistance regularly to prevent multi‐channel introduction and breakout of new HIV strains.

Objective To prepare monoclonal antibodies (mAbs) against GII.4 norovirus P domain by multiple antigens in an immunization program. Methods BALB/c mice were immunized with the multiple GII.4 NoV P domain, namely 1996cluster (VA387), 2004cluster, 2006b cluster and 2010 cluster. The spleen cells from the immunized mice were fused with SP2/0 cells and the hybridoma cells were screened by ELISA. The supernatant of the mAbs was collected and purified by the limiting dilution assay. Its subtype was identified, and the specificity and neutralization were analyzed by indirect ELISA and HBGA blocking, respectively. Results We obtained thirteen hybridoma cell lines that stably secreted mAbs against GII.4 NoV P domain. Their titers reached above 10-4 after purification. The subtypes of the mAbs were identified as IgG1. Indirect ELISA showed that all the mAbs specifically bound to all GII.4 norovirus variants. Five mAbs specifically bound to GII.17, GII.3 and GII.6 variants. Three mAbs specifically bound to GII.2 variants and strongly blocked NoV P particle from binding to the histo-blood group antigen (HBGA) receptors. Conclusion The mAbs against GII.4 norovirus P domain have been obtained by combined antigens immunization program. Multi-antigen immunization can enhance immune response significantly and cross-react with other GII.4 norovirus variants. The findings provide a basis for further development of novel GII.4 norovirus vaccines and for the optimization of the immunization programs of combined multi-antigen vaccine candidates.

目的 研究深圳地区急性肠胃炎住院患儿中人副肠孤病毒(HPeV)的临床和流行病学特征.方法 收集2017年1月到2018年12月深圳地区5岁以下急性肠胃炎住院患儿粪便标本(常规细菌鉴定为阴性)497份,实时荧光RT-PCR方法检测HPeV,通过巢式PCR扩增VP3/VP1连接区片段进行分型,同时对患儿的流行病学和临床资料进行统计分析.结果 497例患儿中,HPeV的阳性率为8.2％;男性HPeV阳性率为7.6％,女性HPeV阳性率为9.4％(χ2=0.491,P=0.501);0～6月龄患儿HPeV阳性率最高,且92.7％的HPeV阳性患儿月龄<24个月;深圳夏季(7～9月)HPeV的阳性率最高.HPeV阳性患儿主要临床表现为中热(38.1～39℃),腹泻频率平均>6次/d,以黏液便为主,常伴有呕吐,呕吐频率平均每天5次,呕吐物以胃内容物为主.HPeV阳性患儿较阴性患儿在有无呕吐和呕吐物性状差异具有统计学意义.本研究中共检测到HPeV-1(HPeV-1A和HPeV-1B亚型)、3、4、5、6和14在内的6种基因型,其中HPeV-1B(56.1％)为优势流行株,其次是HPeV-1A(17.1％)、HPeV-3(7.3％)、HPeV-4(7.3％)、HPeV-5(4.9％)、HPeV-6(4.9％)和HPeV-14(2.4％).系统进化分析结果显示,大部分深圳分离株与兰州和广州来源的参考株核苷酸序列一致性高.结论 本研究首次在深圳地区5岁以下急性肠胃炎住院患儿粪便中检测到HPeV,且在2017年和2018年有稳定的感染率,检测到6种HPeV基因型别可能与急性肠胃炎相关,HPeV夏季检出率最高,好发于0～6个月患儿,可能是引起急性肠胃炎住院患儿呕吐胃内容物的病因.开展HPeV监测以更充分地掌握其在深圳地区的流行和临床特征,有助于进一步明确深圳地区住院患儿病毒性急性肠胃炎病原谱构成.

BACKGROUND:The accurate interpretation of BRCA1/2 variants becomes increasingly important in breast cancer and other related cancers including ovarian cancer, prostate cancer, pancreatic cancer and so forth. In the past decades, especially before year 2015, limitations of techniques and lack of databases and guidelines have led to possible misinterpretation of the clinical significance of sequence variants of BRCA1/2. A published study reported reclassification of some BRCA1/2 variants previously classified as variants of uncertain significance (VUS) to likely pathogenic in breast or ovarian cancer patients from Korea. However, little is known about the situation in Chinese population.METHODS:We retrospectively retrieved 109 publications studying about BRCA1/2 variants of Chinese population from the year 1999 to year 2019 (March). After excluding publications of meta-analysis and publications with missing data, 72 publications were eventually retained for subsequent analysis. In total, 1,351 BRCA variants (673 BRCA1 variants and 678 BRCA2 variants) derived from 42,430 Chinese cancer patients were standardized and reinterpreted using ACMG/AMP 2015 guidelines and China Expert Consensus on BRCA variant interpretation by genetic counselors.RESULTS:Among the 1,351 BRCA variants, the majority of interpretation (91.7%, 1,239/1,351) remained the same as previously published. However, there were 112 (8.3%, 112/1,351) variants (64 BRCA1, 48 BRCA2) reclassified with different categories.CONCLUSIONS:Our results demonstrated that clinical significance of not only VUS, but also pathogenic/likely pathogenic variants varied from time to time in the Chinese population. Precise reinterpretation of BRCA1/2 variants is of crucial importance to genetic counseling or clinical decision-making for risk individuals or patients.

Parechovirus A (PeV-A), which causes a wide variety of diseases, is prevalent among young children. However, little is currently known about PeV-A infections in children with acute gastroenteritis in mainland China. In this study, we investigated the molecular epidemiology of acute gastroenteritis in Shenzhen, southern China, with an emphasis on PeV-A infections. A total of 1220 stool specimens from 1220 outpatient children under 5 years old with acute gastroenteritis were collected from January 2016 to December 2018. Viral RNA was detected by a real-time RT-PCR and PCR method. The PeV-A isolates were genotyped by sequencing the VP3/VP1 region. Of 1220 specimens, 148 (12.1%) were positive for PeV-A. The predominant genotype was PeV-A 1B (68.9%), followed by PeV-A 4 (12.2%), PeV-A 14 (6.1%), PeV-A 1A (5.4%), PeV-A 6 (2.7%), PeV-A 3 (2.7%) and PeV-A 5 (2.0%). It was found that 68.2% of PeV-A infections occurred in the summer and rainy months (June to September) in southern China. The majority of PeV-A-positive patients (97.3%) were younger than 24 months old. PeV-A coinfection with norovirus, rotavirus, astrovirus and adenovirus was found in thirty specimens (30/148, 20.3%), five specimens (5/148, 3.4%), five specimens (5/148, 3.4%), and two specimens (2/148, 1.4%), respectively. Coinfections with more than one other enteric virus were not observed in any of the PeV-A-positive specimens. Phylogenetic analysis revealed that the PeV-A isolates from Shenzhen were closely related to each other and to strains circulating in China, suggesting endemic circulation of PeV-A in China. The results of this study indicate that PeV-A is one of important pathogens of acute gastroenteritis in young children and that coinfection is a possible mode of PeV-A infection. PeV-A associated with acute gastroenteritis exhibited high genotypic diversity in Shenzhen, southern China.

目的 了解广东省江门市1型艾滋病病毒(HIV-1)基因亚型分布状况及其主要流行株CRF01_AE的传播和基因变异特征.方法 收集江门市2018--2019年新确证为HIV-1感染且未经抗病毒治疗的208例样本,采用巢式荧光定量聚合酶链反应法(PCR)扩增gag基因序列并测序,应用Genotyping Tool进行基因分型、PhyML3.0软件构建系统进化树,利用Entropy和VESPA程序对CRF01_AE毒株亚簇进行氨基酸序列特征分析.结果 成功测得gag序列173条,异性性传播占72.83％(126条),同性性传播占17.92％(31条);亚型分析结果显示,CRF01_AE 69例(39.88％),CRF07_BC 57例(32.95％),19例(10.98％) CRF55_01B,12例(6.94％)B亚型,其他亚型包括CRF08_BC、CRF59_01B、C亚型和URFs共16例(9.25％).CRF01_AE在系统进化树上形成4个传播簇,其中2个主要传播簇共有11个氨基酸位点的特征性氨基酸分布存在显著差异,且传播簇Ⅰ的氨基酸多态性大于传播簇Ⅱ.结论 江门市HIV-1亚型分布复杂多样,以异性性传播为主,存在多种传播簇.CRF01_AE亚型为江门地区的优势流行株,其亚簇的氨基酸存在变异.

目的 探究2015-2017年肇庆市感染性腹泻病毒病原学特点及流行特征.方法 随机抽取肇庆市6所不同级别的医院,按一定比例抽样间隔调查门诊就诊的感染性腹泻病例.收集粪便标本细菌培养、病毒检测的结果.结果 914例患者中共检出阳性438例(47.92％),细菌7种(12.91％),其中副溶血性弧菌和沙门菌分别有63例(14.38％)和37例(8.45％);病毒5种(33.15％),其中以诺如病毒阳性241例(55.02％)较为多见;混合感染者17例(3.88％);第三季度、第四季度感染性腹泻高发,其中第三季度细菌与病毒阳性数分别为50例(42.37％)和160例(52.81％);第四季度细菌与病毒阳性数分别为25例(21.19％)和78例(25.74％);细菌与病毒阳性患者的年龄分布都主要集中在20～岁(分别有32例与86例),两组年龄构成差异无统计学意义(P＞0.05);细菌阳性组腹痛、不洁饮食史比例高于病毒阳性、混合感染组(P＜0.05).结论 2015-2017年肇庆市感染性腹泻病原谱较广泛,高发于第三、四季度,需要开展相应综合防控措施.

New recombinant variants are a predominant challenge for preventing the spread of the HIV-1 epidemic. In this study, we confirmed a novel HIV-1 CRF07_BC/CRF55_01B recombinant form for the first time, which was isolated from a male patient in Jiangmen, China. The genomic sequence of the variant with four CRF55_01B segments inserted into the CRF07_BC backbone is 8,510 bp in length, extending from nucleotides 669 to 9,293 according to the HXB2 genome. Specifically, the recombinant strain contains site mutations associated with drug resistance.

诺如病毒(Noroviruses,NoVs)是引起非菌型胃肠炎暴发流行的主要病原体之一.为了解我国GⅡ.3型NoVs毒株的变异以及受体结合模式,本研究对来自2015年一起中国广州NoVs胃肠炎暴发的GⅡ.3型毒株GZ31597株进行聚合酶区和完整VP1区基因扩增、序列测定和序列分析,并表达VP1突出区蛋白(P蛋白),通过P蛋白与不同血型唾液样本的酶免疫分析法(EIA)测定实验确定其组织血型抗原(Histo-blood group antigens,HBGAs)结合模式.GZ31597株聚合酶和VP1基因系统进化分析表明,GZ31597株为GⅡ.P12/GⅡ.3-SubD基因型(聚合酶/衣壳区),该毒株较先前的GⅡ.3毒株相比,在既是抗原表位又是HBGAs受体结合位点的氨基酸385残基发生了氨基酸转换.根据Western Blotting结果,证实P蛋白成功表达.唾液结合分析结果显示,该毒株P蛋白与A、B、AB、O型分泌型以及O型非分泌型唾液均可以结合,但结合值相对低.本研究表明该GⅡ.P12/GⅡ.3-SubD亚型的GⅡ.3毒株在长期的流行过程中,通过氨基酸的转换,改变抗原性和受体结合活性,使GⅡ.3型毒株在人群中继续流行.通过探索GⅡ.3型NoVs在人群中长期广泛流行的原因,为GⅡ.3型诺如病毒性胃肠炎的预防和控制提供重要依据.