Identification of multidrug-resistant Streptococcus pneumoniae strains isolated in Poland by multilocus sequence typing

Multilocus sequence typing (MLST) of 35 isolates of multidrug-resistant Streptococcus pneumoniae recovered in Poland during 1995-1996 distinguished 10 different sequence types (ST). The majority of the isolates were assigned to two Polish clones of serotypes 6B and 23F, although the international clones, Spain23F-1 and Spain9V-3, were also identified. Similar results were obtained using pulsed-field gel electrophoresis (PFGE), providing a direct comparison of these two typing methods.     

兔肌源性干细胞的生物学特性及表型研究

目的:探讨兔肌源性干细胞(MDSCs)的分离及特征和表型研究。方法:取1.5月龄新西兰兔大腿肌肉，采用差速贴壁分离Preplate技术，分别用Ⅺ胶原酶、dispase蛋白酶以及胰蛋白酶分步消化肌肉，并用差速贴壁法分离晚期贴壁的细胞，流式细胞仪(FCM)、免疫细胞化学以及Western blotting等检测初步确定细胞表型。结果:进行连续6 d的差速贴壁分离。第3 d开始得到较多量的圆形或短梭形细胞，簇样生长，体积明显小于骨骼肌细胞及其它杂细胞，10 d左右汇合，有极强的融合生长倾向。细胞在汇合度<30%传代可较好地保持原形态，流式细胞仪检测示MDSCs>80%为desmin+，>70%为Bcl-2+，>95%为CD45-，免疫细胞化学定性示desmin+。Western blotting检测显示随着细胞的纯化，α-SMA表达越来越弱。而细胞高汇合度(>50%)或低血清培养时极易融合成肌管或肌细胞链，skeletal myosin+。结论:MDSCs具有desmin、Bcl-2高水平表达和CD45极低水平表达的特性，具有多向分化能力的MDSCs是组织工程研究的一种新型种子细胞。     

Immunocytochemical localization of caldesmon and calponin in chicken gizzard smooth muscle

Summary The distribution of caldesmon and calponin in chicken gizzard smooth muscle was investigated with immunofluorescence and immunogold electron microscopy. Immunofluorescence microscopy showed that in verapamil treated (relaxed) muscles the distributions of caldesmon and myosin appeared to be uniform throughout the cytoplasm, but clearly more textured than that of actin filaments as revealed by the distribution of tropomyosin. In shortened muscles both caldesmon and myosin became segregated, in contrast to the distribution of actin, which remained uniform. The distribution of calponin was even more textured, with no similarity to those of caldesmon or myosin. Instead, considerable overlap was observed between calponin and the cytoskeletal protein desmin and, to a lesser extent, -actin. By immunogold electron microscopy caldesmon appeared mostly near and around myosin filaments in both relaxed and shortened muscle. Calponin, on the other hand, was found primarily at the periphery of cytoskeletal structures in the same general region as desmin, and very often adjacent to -actin, which is mainly in the core. These observations indicated that caldesmon and calponin are associated with different subsets of actin filaments, caldesmon with contractile actin, while calponin with cytoskeletal actin. Thus the in situ localization of caldesmon is consistent with its proposed regulatory function. Calponin, on the other hand, is unlikely to directly regulate actomyosin interactions in these cells; instead, it may function as a bridging protein between the actin and the intermediate filament networks.     

胡萝卜籽挥发油的抗生育作用

胡萝卜籽挥发油对小鼠有抗着床,抗早、中和晚期妊娠作用。对大鼠也有抗着床作用。挥发油中的萜类碳氢化合物部位,对小鼠皮下注射抗早期妊娠的ED_(50)为2.9ml/kg,甲地孕酮和hCG能明显逆转其作用;对假孕小鼠蜕膜瘤有抑制作用,此作用不能被甲地孕酮拮抗,皮下注射于早孕大鼠24、48小时后血浆孕酮浓度明显下降。以上提示其抗早孕作用机制可能与抑制孕酮合成和蜕膜反应有关。此外,挥发油碳氢部分无雌激素和抗雌激素活性,低浓度时对早孕大鼠离体子宫的收缩活动没有影响,高浓度则表现抑制作用。     

新洁尔灭对小白鼠抗早孕的病理组织学观察

本文报告用不同剂量的新洁尔灭和同体积生理盐水注入怀孕5天小白鼠的宫腔内,3天后杀死,观察其蜕膜、胚泡、宫内膜腺体和卵巢黄体病理学改变。实验表明:对照组无改变。实验组小白鼠的蜕膜细胞全部退变坏死。病变随着给药量的递增而渐趋严重;同时胚泡亦有退变和坏死。提示:新洁尔灭对早期妊娠小白鼠是有抗早孕效果的。根据实验结果,我们认为新洁尔灭对小白鼠抗早孕的机制,很可能是一个综合因素,有直接的,也有间接的。作者强调在抗早孕机制诸因素中,蜕膜退变坏死是一个重要的因素。     

Monitoring effects of α-human atrial natriuretic polypeptide (α-hANP) on left ventricular function in patients with essential hypertension with a cardiac probe

The effects of -hANP on left ventricular function were studied with a cardiac probe in ten patients with essential hypertension. Our data showed that intravenous administration of -hANP significantly elevated left ventricular function. At 5 min, the elevation of EF, RCO, ER, RSV, PFR were 13.23% (P<0.02), 12.7 (P<0.02), 0.618 (P<0.02), 0.133 (P<0.05), 0.283 (P<0.01), respectively. At 10 min, the increase of EF, ER, were 11.07% (P<0.02) and 0.233 (P<0.01), respectively. Atriopeptin significantly reduced systolic and diastolic blood pressure from 2 min to 20 min (P<0.001–0.05).Supported by IAEA Grant No. 4062/RI/RB     

器官培养在研究人食管上皮癌变中的应用

将组织块置于明胶海绵上,摇摆器官培养,4～6周后成人食管粘膜仍保持良好的结构形态,具有活跃生长的上皮细胞和良好的腺体结构;将组织块贴壁,静置外植块—细胞培养,成人食管粘膜和胎儿食管组织块可存活2～3个月,提供大量生长旺盛的上皮细胞。成人食管癌旁粘膜培养利于观察细胞癌前改变,可能较易于诱发癌变;胎儿食管具有正常背景,利于研究细胞癌变的全过程.二者配合可组成研究人食管上皮癌变的完整体外实验系统。     

ALPHA-FETOPROTEIN VARIANTS AND THEIR CLINICAL SIGNIFICANCE

The molecular heterogeneity of serum alpha-fe- toprotein (AFP) in 36 patients was studied by lectin affinity-radioimmunoelectrophoresis. Two variants of AFP, concanavalin-A (Con-A) reactive and the Con-A nonreactive, were obtained. AFP in all 13 patients with hepatoma consisted of the two va- riants, but the Con-A reactive variant was the ma jor one. In 8 patients with benign liver disorder, however, only the Con-A reactive variant of AFP was detected. Over 50"70 0f AFP in 5 patients with yolk sac tumor was Con-A nonreactive. Thus, there were three different patterns of AFP variants. The clinical implications are discussed.     

Cytologic diagnosis of hepatocellular carcinoma by fine-needle aspiration biopsy

From 1976 to June 1982, 237 patients with clinical suspicion of hepatic malignant disease underwent guided percutaneous fine-needle aspiration biopsy of the liver. Of these, 12 were diagnosed cytologically as "hepatocellular carcinoma" and this diagnosis was confirmed in the follow-up of all cases. On the basis of the cytomorphologic features observed in the aspirates, the tumor was subclassified into three types; well differentiated, pleomorphic large cell; and poorly differentiated. The various cytologic appearances of different types of hepatocellular carcinoma are presented and illustrated. Cytomorphologically, these three types of hepatocellular carcinoma were distinctly different and their cytomorphologic features were also sufficiently distinctive from those of secondary hepatic cancer to be diagnostic. Guided percutaneous fine-needle aspiration biopsy of the liver appears to be a definitive minimally invasive means of establishing the diagnosis of hepatocellular carcinoma, and promises to be a valuable diagnostic procedure for potentially resectable localized hepatocellular carcinoma.     

健康成年人接种两剂新型冠状病毒灭活疫苗后序贯加强免疫重组新型冠状病毒疫苗(CHO细胞)的免疫原性和安全性研究

目的 评价在接种两剂已上市新冠病毒灭活疫苗的人群中序贯加强免疫重组新型冠状病毒疫苗(CHO细胞)后的免疫原性和安全性,为制定新型冠状病毒疫苗的加强免疫策略提供科学依据。 方法 采用开放性试验设计,筛选入组360例已接种两剂新冠病毒灭活疫苗3～4个月、6～8个月、11～13个月的18周岁及以上研究对象并接种1剂重组新型冠状病毒疫苗(CHO细胞)。采集所有研究对象研究用疫苗接种前、接种后14 d血样,用于体液免疫检测,收集研究用疫苗接种后1个月内的所有不良事件。 结果 本研究入组360例研究对象,按研究对象加强免疫与基础免疫间隔时间分3组(A组91～120 d,B组181～240 d,C组331～390 d),各组120例,无研究对象脱落。三组年龄均值分别为38.13、40.22和45.73岁,各组间年龄差异有统计学意义(F=13.516,P＜0.001),A、B组差异无统计学意义(P=0.168),C组和A、B组间差异均有统计学意义(P＜0.001)。三组 IgG GMC(几何平均浓度)免疫前分别为4.81、4.23、2.12 AU/ml,差异有统计学意义(F=10.054,P＜0.001),C组和A、B组间差异均有统计学意义(P＜0.001),A、B组间差异无统计学意义(P=0.520);三组免疫后 IgG GMC 分别为106.69、124.05、80.04 AU/ml,差异无统计学意义(F=2.028,P=0.133)。三组 IgG 抗体阳转率分别为84.17%、87.50%、79.17%,差异无统计学意义(χ²=3.081,P=0.214)。免疫前血清针对Delta变异株和原型株不同组别的中和抗体滴度比较,三组原型株中和抗体GMT(几何平均滴度)为1∶2.18、1∶2.18、1∶2.19,差异无统计学意义(F=0.011,P=0.990);三组Delta变异株中和抗体GMT为1∶2.09、1∶2.17、1∶2.16,差异无统计学意义(F=0.378,P=0.686)。免疫后血清三组原型株中和抗体 GMT为1∶31.09、1∶34.90、1∶21.98,差异无统计学意义(F=2.262,P=0.106);三组Delta变异株中和抗体GMT为1∶61.46、1∶77.44、1∶43.71,差异无统计学意义(F=2.105,P=0.123)。序贯加强免疫后血清对新型冠状病毒Delta变异株和原型株的中和抗体阳转率分别达到82.78%、83.33%。三组 SARS-CoV-2原型株中和抗体阳转率分别为86.67%、87.50%、75.83%,差异有统计学意义(χ²=7.320,P=0.026),其中C组低于A组和B组;三组 SARS-CoV-2 Delta变异株中和抗体阳转率分别为87.50%、84.17%、76.67%,差异无统计学意义(χ²=5.183,P=0.075)。发生不良事件人数为124人,不良事件总体发生率为34.44%。各组发生率分别为35.83%、40.83%和26.67%,差异无统计学意义(χ²=5.487,P=0.064),所有研究对象出现的不良事件以接种部位不良事件为主,主要表现为疫苗接种部位疼痛(23.89%);全身不良事件主要表现为疲劳/乏力(6.94%),未发生与疫苗接种有关的SAEs。结论 接种两剂新型冠状病毒灭活疫苗后序贯加强免疫重组新型冠状病毒疫苗(CHO细胞)具有良好的免疫原性和安全性。较长间隔期的免疫前IgG和免疫后原型株中和抗体阳转率较低,不同间隔期的免疫后IgG 、Delta变异株和原型株中和抗体水平比较差异均无统计学意义,建议基础免疫后6~8个月为最佳的接种间隔。