黄芩甙体外抗解脲支原体作用

为了观察黄芩提取物黄芩甙抗解脲支原体的作用,揭示黄芩甙的更广泛的抗病原体效应,采用液体培养基稀释法,测定黄芩甙对解脲支原体体外抑菌效应。黄芩甙对解脲支原体的最低抑菌浓度(MIC)为1.87~4.32 mg/mL。黄芩甙对解脲支原体有明显抑制作用。     

支原体培养基的改良及其效果评价

为了改良支原体培养基配方,评价其效果。按《中华人民共和国药典》(以下简称药典)中规定的灵敏度比较方法,将实验室制备的新型支原体改良培养基与《药典》中支原体检查法推荐的处方培养基和商品化支原体培养基进行灵敏度效果比较试验。结果表明,改良后的支原体肉汤和半流体培养基,与接种口腔支原体和肺炎支原体及其它支原体的精氨酸培养基、支原体肉汤培养基无显著差异;与接种肺炎支原体的支原体半流体培养基无显著差异;与接种口腔支原体的支原体半流体培养基差异显著。因此经改良后的支原体培养基灵敏度能够满足药典规定的要求,但其操作简便,且成本低于现有的支原体培养基。     

The gene mpn310 (hmw2) from Mycoplasma pneumoniae encodes two proteins, HMW2 and HMW2-s, which differ in size but use the same reading frame

The gene mpn310 from Mycoplasma pneumoniae encodes the proteins HMW2 with a molecular weight of 215 621 and the smaller P28, here called HMW2-s. Because HMW2-s is not well defined, it was isolated from protein extracts of M. pneumoniae cells and its N-terminal end was determined by MS. HMW2-s starts with the methionine at the amino acid position 1620 of HMW2 and its residual sequence is identical to the last 198 amino acids of HMW2, predicting a molecular weight of 23 204. These results were confirmed by the comparative MS analysis of HMW2-s that had been synthesized in Escherichia coli . A precursor–product relationship between HMW2 and HMW2-s could be excluded, because HMW2-s can be translated from a specific mRNA starting within mpn310 . The conservation of an HMW2-s like protein in M. pneumoniae and Mycoplasma genitalium emphasizes its possible functional importance.     

A novel method for the determination of electrical potentials across cellular membranes. II. Membrane potentials of acholeplasmas, mycoplasmas, streptococci and erythrocytes

The membrane potentials of Acholeplasma laidlawii, Mycoplasma mycoides subsp. capri, Mycoplasma gallisepticum, Streptococcus faecalis and human erythrocytes have been determined by applying a novel technique. The membrane potentials were calculated simply from potassium concentrations determined by atomic absorption spectroscopy, and gravimetry. The versatility of the new technique is demonstrated by comparing our results with data obtained by different techniques.     

Interactions between mycoplasma lipoproteins and the host immune system

Mycoplasmas typically have a number of distinct lipoproteins anchored on the outer face of the plasma membrane. These surface antigens have a potent modulin activity and are preferential targets of the host immune response. However, the variation of some of these lipoproteins provides mycoplasmas with an effective means of evading the host immune defence system.     

Characterization of a lympho-inhibitory peptide produced by Mycoplasma bovis

Mycoplasma bovis is able to inhibit the mitogen-induced proliferation of bovine lymphocytes. Herein is described the isolation of an immuno-inhibitory peptide from M. bovis. Using size exclusion chromatography, three lympho-suppressive fractions were isolated from M. bovis free supernatant. MALDI-TOF analysis revealed a common peak throughout the suppressive fractions. The purest of these fractions was subjected to N-terminal sequencing, revealing an 84% homologous match with the C-terminus of the M. bovis surface protein VspL (variable surface protein-L). A recombinant of the 26 amino acid peptide was also able to suppress Concanavalin A (ConA)-induced proliferation of bovine lymphocytes. This describes a unique immunosuppressive peptide produced by the bovine respiratory pathogen, M. bovis.     

Internalization and intracellular survival of Mycoplasma pneumoniae by non-phagocytic cells

Current theory holds that mycoplasmas remain attached to the surface of epithelial cells although some mycoplasmas have evolved mechanisms for entering host cells that are not naturally phagocytic. The ability of Mycoplasma pneumoniae strain M129 to invade and survive within host cells was studied using a HeLa cell line and a human lung carcinoma cell line (A549). The invasion process into the eukaryotic cells was studied qualitatively by confocal laser scanning microscopy and quantitatively by the gentamicin resistance assay. Internalization was found with A549 cells but not with HeLa cells. Internalization was dependent on the duration of the infection and on temperature. The organism, detected in the cytoplasm and perinuclear regions, survived within the host cells for prolonged periods of time. The intracellular location of M. pneumoniae is obviously a privileged niche, well protected from the immune system and from the action of many antibiotics and may explain the pathogenic potential of this organism.     

性病后慢性前列腺炎病原微生物分析

本文对性病后慢性前列腺炎病原微生物进行了研究。９０例患者前列腺液支原体检出率为２４．４４％（２２／９０）,其中解脲支原体为２２．００％（１８／９０）,人型支原体为４．４４％（４／９０）。另一组２３２例患者进行前列腺液细菌培养鉴定,总检出率为４２．７％（９９／２３２）,以金黄色葡萄球菌为主２４．５％（５７／２３２）,其它菌依次为表皮葡萄球菌７．３％（１７／２３２）,肠球菌４．３％（１０／２３２）,非发酵菌２．６％（６／２３２）,肠杆菌科细菌２．２％（５／２３２）和Ａ群链球菌１．７％（４／２３２）。作者认为,性病后慢性前列腺炎可能为急性尿道炎期,由于治疗不彻底或忽略非特异性性病病原菌的治疗而使条件致病菌上行感染所致。     

支原体生殖道感染妇女阴道微生态改变对临床转归的影响及XGboost模型构建

摘要 目的：探讨支原体生殖道感染妇女阴道微生态改变对临床转归的影响,并构建XGboost模型。方法：选取2019年1月~2020年12月于我院妇科门诊确诊的支原体生殖道感染妇女186例。根据治疗后3个月的临床转归分为有效组145例和无效组41例。比较两组患者的临床资料、阴道微生态形态学指标和功能学指标、微生态类型。使用Cox比例风险回归森林图筛选影响支原体生殖道感染妇女临床转归的因素,利用筛选出的影响因素构建XGboost模型并对影响因素按重要度排序,ROC曲线分析XGboost模型对支原体生殖道感染妇女临床转归的预测效能,校准曲线评价XGboost模型的准确度,临床决策曲线评价XGboost模型的有效性。结果：两组患者的流产次数、学历、年龄、避孕方式、生产次数对比有差异（P<0.05）。与有效组相比,无效组患者阴道微生态形态学和功能学各指标异常发生率、阴道微生态失调率明显较高（P<0.05）,无效组的需氧型阴道炎（AV）、外阴阴道假丝酵母菌病（VVC）、细菌性阴道病（BV）、BV+VVC、滴虫性阴道炎（TV）、BV中间型+VVC的检出率均明显较高（P<0.05）,无效组正常微生态及菌群正常、功能下降所占人数比例均明显更低,差异均有统计学意义（P<0.05）。年龄<25岁、高中以下学历、流产次数>1次、生产产次≥3次以及阴道微生态失调是影响支原体生殖道感染转归的重要因素（P<0.05）。构建的XGboost模型具有较高的预测效能,准确度和有效性均较高。结论：年龄、学历、流产次数、生产次数以及阴道微生态失衡是影响支原体生殖道感染临床转归的重要因素,本研究构建的XGboost模型具有较好的预测效能。     

Lipid and protein membrane components associated with cholesterol uptake by mycoplasmas

Membranes of Mycoplasma species take up 2–4 times more exogenous cholesterol than membranes of Acholeplasma species. To test whether the lower cholesterol uptake capacity of Acholeplasma is due to the high glycolipid content of their membranes, the phospholipids of Acholeplasma laidlawii and Mycoplasma capricolum membranes were hydrolyzed by phospholipase A². Digestion removed about 30% of the polar lipids of A. laidlawii, leaving the glycolipids and phospholglycolipids intact, and about 70% of the polar lipids of M. capricolum, the residue consisting mostly of sphingomyelin. Cholesterol uptake by the treated membranes from phosphatidylcholine/cholesterol vesicles decreased in rough proportion to the amount of polar lipid removed, indicating that the glycolipids in A. laidlawii membranes can participate in cholesterol uptake.Trypsin digestion of growing cells and isolated membranes of M. capricolum decreased cholesterol uptake by about one-half. Similar treatment of A. laidlawii cells and membranes had no effect on cholesterol uptake. These findings suggest the existence of protease-sensitive receptors on the cell surface of M. capricolum responsible for tighter contact with the cholesterol/phosphatidylcholine vesicles. It is proposed that the ability of Mycoplasma species to take up large quantities of exogenous cholesterol and phospholipids depends on the presence of protein receptors for cholesterol donors, receptors which are absent in Acholeplasma species.