Immunisation with the BCG and DTPw vaccines induces different programs of trained immunity in mice

In addition to providing pathogen-specific immunity, vaccines can also confer nonspecific effects (NSEs) on mortality and morbidity unrelated to the targeted disease. Immunisation with live vaccines, such as the BCG vaccine, has generally been associated with significantly reduced all-cause infant mortality. In contrast, some inactivated vaccines, such as the diphtheria, tetanus, whole-cell pertussis (DTPw) vaccine, have been controversially associated with increased all-cause mortality especially in female infants in high-mortality settings. The NSEs associated with BCG have been attributed, in part, to the induction of trained immunity, an epigenetic and metabolic reprograming of innate immune cells, increasing their responsiveness to subsequent microbial encounters. Whether non-live vaccines such as DTPw induce trained immunity is currently poorly understood. Here, we report that immunisation of mice with DTPw induced a unique program of trained immunity in comparison to BCG immunised mice. Altered monocyte and DC cytokine responses were evident in DTPw immunised mice even months after vaccination. Furthermore, splenic cDCs from DTPw immunised mice had altered chromatin accessibility at loci involved in immunity and metabolism, suggesting that these changes were epigenetically mediated. Interestingly, changing the order in which the BCG and DTPw vaccines were co-administered to mice altered subsequent trained immune responses. Given these differences in trained immunity, we also assessed whether administration of these vaccines altered susceptibility to sepsis in two different mouse models. Immunisation with either BCG or a DTPw-containing vaccine prior to the induction of sepsis did not significantly alter survival. Further studies are now needed to more fully investigate the potential consequences of DTPw induced trained immunity in different contexts and to assess whether other non-live vaccines also induce similar changes.     

Antibacterial activities of the leaf extracts of Eugenia uniflora Linn. (Synonym Stenocalyx michelli Linn.) Myrtaceae

The aqueous, organic, and volatile oil extracts of leaves of Eugenia uniflora Linn. Family Myrtaceae were investigated for antibacterial properties using agar dilution techniques. The aqueous extract was the most active against the organisms compared to the organic and volatile oil extracts. The extracts were found to inhibit Gram positive Staphylococcus aureus and Bacillus subtilis and Gram negative Escherichia coli and Shigella dysentcriae. Pseudomonas aeruginosa, Klebsiella pneumoniac, and Salmonella typhi were not inhibited.     

枯草杆菌Bacillus sp F26产过氧化氢酶的发酵条件

从内蒙古呼伦贝尔草原的盐碱湖中分离到的一株低度嗜盐嗜碱细菌Bacillus sp F26，能积累高水平过氧化氢酶（CAT）。对Bacillus sp F26发酵产过氧化氢酶的环境与营养条件的研究结果表明，其积累高水平过氧化氢酶的适宜环境条件为：温度37℃，种龄20-22h，接种量5％，装液量50mL／（250mL的摇瓶）。适宜发酵培养基组成（g／L）为：葡萄糖15，牛肉膏10，玉米浆10，酵母膏5，磷酸二氢钾1，氯化镁0．2，氯化钠50，碳酸钠10。采用上述条件进行摇瓶分批发酵实验，发酵20h，过氧化氢酶酶活达到16．32U／mL，细胞干重为4．12g／L。进一步研究发现，在对数生长后期（16h）添加2mmol／L的H2O2可以明显刺激产酶，在5L的发酵罐上进一步以指数速率方式流加H2O2，由于该流加方式可降低H2O2对细胞的毒害作用，过氧化氢酶酶活达到29．89U／mL，与分批发酵相比提高了92．8％。     

高渗透压对细菌电转化率的影响

研究了革兰氏阴性细菌大肠杆菌JM109和革兰氏阳性细菌地衣芽孢杆菌0204在电转化过程中,高渗溶液如山梨醇、甘露醇、甘油、蔗糖和葡萄糖对其电转化率的影响.结果表明,高渗溶液能够有效保护细胞,提高转化率.在复苏培养基中,0.7mol/L甘露醇对地衣芽孢杆菌0204的保护效果最好,0.1mol/L蔗糖对大肠杆菌JM109的保护效果最好.由此得到质粒DNA对地衣芽孢杆菌0204的最高电转化率为9.8×102转化子/μg,质粒DNA对大肠杆菌JM109的最高电转化率为5.9×108转化子/μg.     

沙市城区连续10年应用微生物制剂控制蚊虫的效果评价

目的：观察10年来主要应用苏云金杆菌以色列变种地方株（B．t－187）控制蚊虫的效果。方法：按WHO推荐的方法，在实验室进行生物测定，以确定B．t－187乳剂使用浓度，然后进行现场灭蚊效果观察。结果：使用效价为380～460国际单位，剂量为1～2ml／m2的B．t－187乳剂能有效控制蚊约和成蚊密度，成蚊平均相对叮咬密度比处理前下降89．4％，并降低了蚊虫的季节性高峰。结论：该生物制剂对按蚊、库蚊、伊蚊幼虫的毒杀效果颇佳，蚊幼尚无产生抗性的迹象。     

卡介苗对哮喘豚鼠的影响

目的 研究卡介苗对哮喘豚鼠的防治作用。方法 24只豚鼠随机分为阳性对照组、地塞米松组、卡介苗组及阴性对照组,每组6只,除阴性对照组用生理盐水外,其余三组每只腹腔内注射鸡卵蛋白100mg,2周后用1％鸡卵蛋白激发致敏,每次30min,每日1次,持续3d,地塞米松组每次激发前肌注地塞米松2mg/kg,卡介苗组每次激发前肌往卡介苗30mg/kg,阳性对照组每次激发前30min肌注生理盐水2ml,最后用乌拉坦麻醉,检验动脉血气分析参数,嗜酸粒细胞(EOS)计数等参数,所有参数用t检验或卡方检验分析。结果 阳性对照组与其它三组比较,在豚鼠的发病程度、动脉血气分析、外周血EOS计数、支气管肺泡灌洗液中EOS计数、支气管病理切片每20个高倍视野EOS计数均有明显差异(P<0.05或P<0.01)。结论 卡介苗能够抑制动物模型中的哮喘反应。     

炭疽芽胞杆菌的感染与生物恐怖

综述了炭疽生物恐怖、炭疽在中国的流行概况、实验室诊断方法的最新进展。同时介绍了炭疽的预防与控制，提出了应对可能发生的生物恐怖应采取的措施。     

卡介苗诱导U-937及THP-1巨噬细胞释放一氧化氮的实验研究

目的 :利用不同的人巨噬细胞株 ,观察其在卡介苗 (BCG)诱导下产生一氧化氮 (NO)的可能性 ,探讨人体巨噬细胞在吞噬、杀灭结核分支杆菌过程中NO的作用。方法 :培养THP 1及U 937巨噬细胞 ,用抗酸染色方法 ,观察THP 1及U 937巨噬细胞对BCG的吞噬率 ;设不同细胞数组 ,添加不同剂量BCG ,用Griess法检测上清液中NO的含量。结果 :U 937巨噬细胞、THP 1巨噬细胞对BCG的吞噬率分别为 (14 .82± 2 .12 ) % ,(5 5 .71±8.4 2 ) % ,与U 937相比 ,THP 1对BCG有更强的吞噬能力 (P <0 .0 1) ;在不同细胞数组中 ,添加BCG均可以明显提高U 937和THP 1两种巨噬细胞对NO的分泌 ,并随着添加BCG剂量的增加而分泌增加。只有在添加大量BCG后 ,才有较大量NO产生。结论 :NO参与人巨噬细胞吞噬、杀灭结核菌的过程 ,在大量结核菌感染后 ,NO可能发挥更大的杀菌作用     

消毒剂敌菲特的研究

经全面考察研究,敌菲特缓释消毒灭菌剂具有良好的消毒灭菌效果,对细菌繁殖体、病毒和细菌芽孢均可完全灭活;即使在—20℃低温条件下,对枯黑变种芽孢仍具很好的杀灭效果。此外,该消毒剂基本克服了氯制剂对金属腐蚀性的缺陷;原药性能基本稳定。     

枯草杆菌BF-7658α-淀粉酶生产菌株所产蛋白酶热稳定性研究

我国α—淀粉酶(EC3.2.1.1)生产是用枯草杆菌BF—7658菌株,它产生的酶是个复杂酶系。其中混杂的蛋白酶未见酸性蛋白酶。发酵液经热处理后,测蛋白酶活力。结果,碱性蛋白酶耐热性比中性蛋白酶强。发酵液经55℃,30分钟热处理后,碱性蛋白蛋残存活力与室温(20～25℃)下碱性蛋白酶活力相差不显著(P>0.05),而中性蛋白酶则相差显著(P<0.05)。用电泳法观察发酵液蛋白酶电泳谱型,显示两条蛋白酶区带。