2018年至2019年浙江省绍兴市新确证人类免疫缺陷病毒1型感染者的分子传播网络特征分析

目的分析浙江省绍兴市新确证人类免疫缺陷病毒1型(human immunodeficiency virus type 1,HIV-1)感染者传播关系的分子网络特征,为疫情流行趋势和防治提供依据。方法纳入2018年8月至2019年12月绍兴市新确证未经抗病毒治疗的423份HIV-1感染/艾滋病病例血液样本,获得375份样本序列,采用反转录聚合酶链反应和巢式聚合酶链反应扩增HIV-1的pol基因,采用MEGA 6.0软件构建系统进化树分析亚型,并采用HyPhy软件和Cytoscape 3.7.2。生成不同基因距离的分子网络,通过美国斯坦福大学HIV耐药数据库在线软件工具分析耐药突变位点。结果375份样本序列中发现8种亚型,优势亚型为流行重组型(circulating recombinant form,CRF)07BC 215份(57.33%),CRF01AE 103份(27.47%),其他包括CRF08BC、CRF85BC、CRF5501B、B、C和CRF01AE/B亚型。在基因距离为1.50%时,共形成24个分子簇,194条序列入网,入网率为51.73%。在分子簇最多的0.75%基因距离时,共形成30个分子簇,129条序列入网,入网率为34.40%,35例以老年人为主的病例聚集成CL1簇。42份样本存在监测性耐药突变(surveillance drug resistance mutation,SDRM),耐药传播率为11.20%(42/375),其中非核苷类反转录酶抑制剂耐药突变38例,分别为K103N(32/375,8.53%)、K103S(4/375,1.07%)、Y188L(1/375,0.27%)和G190A(1/375,0.27%),蛋白酶抑制剂耐药突变4例,分别为M46I(3/375,0.80%)和V82A(1/375,0.27%)。分子簇C2序列携带高比例耐药突变(94.29%,33/35)。结论绍兴市HIV-1亚型丰富多样,CRF07BC亚型传播迅速;在0.75%基因距离仍聚集的CL1簇老年病例亟待干预,防止该耐药毒株的进一步快速传播。     

急性白血病患者雌激素受体多药耐药相关蛋白的检测及临床意义

目的 :探讨雌激素受体 (ER)、多药耐药相关蛋白 (MRP)表达与临床疗效的关系 ,为耐药白血病寻找新的治疗途径。方法 :采用免疫组化ABC法检测了 37例急性白血病 (AL)复发难治患者骨髓单个核细胞的ER与MRP表达。结果 :①ER阳性组CR率为 91.6 7% (11/ 12 ) ,阴性组为 2 8.0 0 % (7/ 2 5 ) ,ER阳性组CR率显著优于阴性组 (P <0 .0 1)。②MRP阳性组CR率为 2 3.81% (5 / 2 1) ,MRP阴性组为 81.2 5 % (13/ 16 ) ,MRP阳性组CR率明显差于阴性组 (P <0 .0 1)。③ 37例AL患者中 ,8例ER +/MRP -与 17例ER - /MRP +患者其ER与MRP表达的一致性很好 (Kappa系数 =0 .83,P <0 .0 1)。另有ER +/MRP +4例 ,ER - /MRP - 8例 ,其ER与MRP表达缺乏一致性。结论 :ER与MRP表达有一定的一致性 ,且与临床疗效有一定关系 ;ER与MRP检测有助于疗效和预后的判定     

Tracheal diameter as a predictor of pulmonary function

Tracheal diameter (TD) was measured from standard posterior-anterior (PA) roentgenograms and evaluated as a predictor of pulmonary function. A population of 222 non-smokers with normal chest roentgenograms was analyzed. A subset of the population with the trachea indented two or more mm by the aorta (on PA film), as well as males and females, were analyzed separately. In males without aortic indentation of the trachea, tracheal diameter alone accounted for 28% of the variation in peak expiratory flow rate (PEFR). Age and height accounted for an additional 19% of the variation. Tracheal diameter was second to age as a predictor for forced expiratory volume in one second (FEV₁) and forced vital capacity (FVC), accounting for an additional 10% of the variation in each. However, tracheal diameter did not explain significant variability in the female group. This study supports an upper airway effect on flow at large lung volumes. It also demonstrates that a tracheal diameter, measured from a PA chest film, is a useful predictor of pulmonary function that can be easily applied in population surveys.     

应用HIV-1耐药性基因型检测广东部分地区HIV耐药株

目的利用艾滋病病毒1型(HIV-1)耐药性基因型检测法,在HIV-1感染者中监测HIV-1耐药性病毒株,掌握广东省HIV-1感染者在利用抗病毒药物治疗前是否存在耐药突变及其流行情况。方法从未接受高效抗逆转录病毒联合疗法(HAART)治疗的HIV-1感染者血浆中提取病毒RNA,采用套式PCR扩增目的基因片断,并对扩增片断进行序列测定和分析。结果HIV-1耐药性基因型检测法能够从HIV-1感染者血浆病毒载量大于1 000拷贝/ml以上、CD4低于400以下的样本中扩增到目的片断。在广东省50例未治疗对象中,低中度耐药相关突变例数为2例,占4%;高度耐药相关突变例数为0;总耐药相关突变例数为2例,占4%。结论HIV-1耐药性基因型检测法能有效地监测HIV-1感染者血浆中的耐药性病毒株的存在,并且方法提供的结果准确、可靠。对广东省未接受抗病毒治疗的HIV-1感染者中耐药突变的检测表明,HIV-1感染者中存在病毒的耐药性突变,也反应了HIV毒株自然变异情况的存在。     

广州地区淋球菌对环丙沙星耐药的监测与分析

目的 为了解广州地区1998～2002年淋球菌对环丙沙星敏感性和耐药性的变迁。方法 采用琼脂稀释法测定环丙沙星对每年分离的淋球菌的最低抑菌浓度(MIC)。结果 对1998～2002年在广州市性病监测中心就诊的性病患者中分离到的603株淋球菌，进行耐药性分析，环丙沙星的敏感率由1998年的12％降至2002年的零敏感，而耐药率由1998年的56．5％上升至2002年的98％。结论 广州地区流行的淋球菌的耐药情况日趋严重，喹诺酮类药物的高耐药率表明已不再适宜被推荐为治疗淋病的一线药物。有必要持续监测淋球菌的耐药性，并减少抗菌药物的滥用，以保证药物的敏感性。     

Network remodeling of intramural coronary resistance arteries in the aged rat: A statistical analysis of geometry

AimsTo identify the geometrical alterations in the age-remodeled rat coronary artery network and to develop a useful technique to analyze network properties in the rat heart.Methods and resultsWe analyzed the networks of the left anterior descendent coronary arteries on in situ perfused hearts of young (3 months) and old (18 months) male rats. All segments and branching over >80 μm diameter were analyzed using 50 μm long cylindrical ring units of the networks. Arterial widening and paucity, increased tortuosity were typical features in the old network. In addition, axis angles deviated more from the mother branches in the old, whereas the diameters of daughter branches fit the Murray law in both groups. The detected changes in the old network resulted in a longer blood flow route for the same direct distance.ConclusionWe developed a useful method to investigate arterial network property changes in the rat heart. Ageing resulted in longer, more tortuous flow route in the LAD network that might be hemodynamically disadvantageous.     

Beetroot juice supplementation increases concentric and eccentric muscle power output. Original investigation

ObjectivesBeetroot juice (BJ) supplementation has been reported to enhance skeletal muscle contractile function; however, it is currently unclear whether BJ supplementation elicits comparable improvements in power output during different types of skeletal muscle contractions. The purpose of the current study was to assess the effect of BJ supplementation on power output during concentric (CON) and eccentric (ECC) muscle contractions during a half-squat.DesignIn a randomized, double-blind placebo-controlled crossover design, eighteen adult males (age: 22.8 ± 4.9 y) completed two experimental testing sessions 2.5 h following the acute ingestion of 140 mL nitrate-rich BJ concentrate or a placebo.MethodsEach experimental session comprised four sets of eight all-out half-squat repetitions with each set completed with a different moment intertia (0.025, 0.050, 0.075 and 0.100 kg·m^?2).ResultsCompared to placebo, BJ supplementation increased mean power output (MP) during the CON (ES: 0.61–1.01) and ECC (ES: 0.54–0.89; all p < 0.05) movement phases to a similar extent. Moreover, comparable increases in peak power output (PP) during the CON (ES: 0.86–1.24) and ECC (ES: 0.6–1.08; all p < 0.05) movement phases were observed following BJ supplementation.ConclusionAcute BJ supplementation increased mean and peak lower limb power output in the concentric and eccentric movement phases of a half-squat. These findings improve understanding of the effects of BJ supplementation on skeletal muscle contractile function and might have implications for enhancing sports performance in events where muscle power output is a key performance determinant.     

Antimicrobial resistance of Haemophilus influenzae isolates from pediatric hospitals in Mainland China: Report from the ISPED program, 2017–2019

PurposeThis study set out to determine the antimicrobial resistance trends of Haemophilus influenzae isolates from pediatric hospitals in Mainland China, which would provide basis for clinical treatment.MethodsThe Infectious Disease Surveillance of Pediatrics (ISPED) collaboration group conducted this study. H. influenzae strains isolated from nine pediatric hospitals in Mainland China were included. Disk diffusion method was used for antimicrobial susceptibility test. Cefinase disc was used for detection of β-lactamase.ResultsIn total, 13810 H. influenzae isolates were included during 2017–2019: 93.17% of which were from respiratory tract specimens, 4.63% from vaginal swabs, 1.10% from secretion, and 1.10% from others. Of all strains, 63.32% isolates produced β-lactamase; 8.22% isolates were β-lactamase-negative and ampicillin-resistant (BLNAR). The resistance to sulfamethoxazole-trimethoprim was 70.98%, followed by resistance to ampicillin (69.37%), cefuroxime (51.35%), ampicillin-sulbactam (38.82%), azithromycin (38.21%), amoxicillin-clavulanate (35.28%). More than 90% of H. influenzae isolates were susceptible to ceftriaxone, cefotaxime, meropenem, levofloxacin and chloramphenicol. The resistance rate of ampicillin and azithromycin in H. influenzae showed an increasing trend through the years. Statistically significant differences in antibiotic-resistance rates of all the antibiotics except chloramphenicol were found in different regions. The major Multi-Drug Resistance pattern was resistant to β-lactams, macrolides, and sulfonamides.ConclusionsThere is a rising trend of resistance rate of ampicillin and azithromycin in H. influenzae. Antimicrobial resistance of H. influenzae deserves our ongoing attention. Third-generation cephalosporin could be the preferred treatment option of infections caused by ampicillin-resistant H. influenzae.     

Distribution of pathogens and antimicrobial resistance in bacteraemia according to hospitalization duration: a nationwide surveillance study in Switzerland

ObjectivesChanging microorganism distributions and decreasing antibiotic susceptibility with increasing length of hospital stay have been demonstrated for the colonization or infection of selected organ systems. We wanted to describe microorganism distribution or antibiotic resistance in bacteraemia according to duration of the hospitalization using a large national epidemiological/microbiological database (ANRESIS) in Switzerland.MethodsWe conducted a nationwide, observational study on bacteraemia using ANRESIS data from 1 January 2008 to 31 December 2017. We analysed data on bacteraemia from those Swiss hospitals that sent information on a regular basis during the entire study period. We described the pathogen distribution and specific trends of resistance during hospitalization for Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Serratia marcescens and Staphylococcus aureus.ResultsWe included 28 318 bacteraemia isolates from 90 Swiss hospitals. The most common aetiology was E. coli (33.4%, 9459), followed by S. aureus (16.7%, 4721), K. pneumoniae (7.1%, 2005), Enterococcus faecalis (5.2%, 1473), P. aeruginosa (4.3%, 1228), Streptococcus pneumoniae (4.3%, 1208) and Enterococcus faecium (3.9%, 1101). We observed 489 (1.73%) S. marcescens isolates. We observed an increasing trend for E. faecium (from 1.5% at day 0 to 13.7% at day 30; p < 0.001), K. pneumoniae (from 6.1% to 7.8%, p < 0.001) and P. aeruginosa (from 2.9% to 13.7%, p < 0.001) with increasing duration of hospitalization; and decreasing trends for E. coli (from 41.6% to 21.6%; p < 0.001) and S. aureus (p < 0.001). Ceftriaxone resistance among E. coli remained stable for the first 15 days of hospitalization and then increased. Ceftriaxone resistance among K. pneumoniae and S. marcescens and oxacillin resistance among S. aureus increased linearly during the hospitalization. Cefepime resistance among P. aeruginosa remained stable during the hospitalization.DiscussionWe showed that hospitalization duration is associated with a species- and antibiotic class-dependent pattern of antimicrobial resistance.