微生物学复兴的机遇、挑战和趋势

历史上,微生物学的发展曾经历了两个辉煌的黄金时代,也经历了其发展的低谷时期。近20年来,随着基因组学、结构生物学、生物信息学、PCR技术、高分率荧光显微镜及其它物理化学理论和技术等的应用,使微生物学的研究取得了一系列突破性进展,微生物学己走出其低谷,开始进入它的第三个黄金时代。本文就下列几个方面谈谈自已对当今微生学发展的机遇、挑战和趋势的一些认识,供读者参考:(1)历史上微生物学发展的两个黄金时代;(2)微生物学复兴的机遇和挑战;(3)当前微生物学发展的特点和趋势;(4)整合微生物学——第三个黄金时代的重要特征。     

金双歧对先天性巨结肠患儿术后炎症因子水平及肠道微生态的影响

目的探讨金双歧对先天性巨结肠患儿术后炎症因子水平及肠道微生态的影响。方法选取2014年3月-2019年3月福建医科大学附属泉州第一医院收治的60例行先天性巨结肠手术的患儿为研究对象,将其随机分为对照组与观察组,每组各30例,对照组给予常规治疗,观察组在对照组基础上给予金双歧治疗。比较两组患儿治疗后胃肠功能恢复指标、治疗前后血清炎症因子水平、治疗前后肠道微生态结构及复杂度、药物不良反应及并发症情况。结果治疗后观察组患儿肠鸣音恢复时间及肛门排气时间均显著短于对照组(均P<0.05);治疗前两组患儿的血清肿瘤坏死因子-α(TNF-α)、白细胞介素-8(IL-8)、超敏C-反应蛋白(hs-CRP)水平相近(均P>0.05),治疗后两组患儿的血清TNF-α、IL-8、hs-CRP水平较治疗前均显著降低(均P<0.05),且观察组显著低于对照组(均P<0.05);治疗后两组患儿肠道微生物属水平相对丰度均较治疗前改善(均P<0.05),且治疗后观察组双歧杆菌属、乳杆菌属、乳球菌属、拟杆菌属相对丰度高于对照组(均P<0.05),链球菌属、葡萄球菌属、梭菌属、沙门菌、鲍曼不动杆菌、瓦氏菌属、其他属相对丰度均低于对照组(均P<0.05),治疗后两组肠道微生态Chao1指数及Shannon指数均升高(均P<0.05),且观察组均高于对照组(均P<0.05);两组治疗期间的药物不良反应发生率及并发症发生率均相近(均P>0.05)。结论先天性巨结肠患儿术后服用金双歧有助于胃肠功能恢复,减轻炎症反应,改善肠道微生态结构及复杂度,安全性好。     

The Relationship between the Golden Spiny Mouse Circadian System and Its Diurnal Activity: An Experimental Field Enclosures and Laboratory Study

Examples of animals that switch activity times between nocturnality and diurnality in nature are relatively infrequent. Furthermore, the mechanism for switching activity time is not clear: does a complete inversion of the circadian system occur in conjunction with activity pattern? Are there switching centers downstream from the internal clock that interpret the clock differently? Or does the switch reflect a masking effect? Answering these key questions may shed light on the mechanisms regulating activity patterns and their evolution. The golden spiny mouse (Acomys russatus) can switch between nocturnal and diurnal activity. This study investigated the relationship between its internal circadian clock and its diurnal activity pattern observed in the field. The goal is to understand the mechanisms underlying species rhythm shifts in order to gain insight into the evolution of activity patterns. All golden spiny mice had opposite activity patterns in the field than those under controlled continuous dark conditions in the laboratory. Activity and body temperature patterns in the field were diurnal, while in the laboratory all individuals immediately showed a free‐running rhythm starting with a nocturnal pattern. No phase transients were found toward the preferred nocturnal activity pattern, as would be expected in the case of true entrainment. Moreover, the fact that the free‐running activity patterns began from the individuals' subjective night suggests that golden spiny mice are nocturnal and that their diurnality in their natural habitat in the field results from a change that is downstream to the internal clock or reflects a masking effect.     

磷酸化的JNK和p38在高温致神经管畸形上皮细胞中的表达变化

目的 探讨高温致神经管畸形（neural tube defects,NTD）的分子机制,为防治神经管畸形提供理论依据.方法 利用高温致金黄地鼠NTD动物模型,应用免疫荧光染色技术,观察NTD发生过程中磷酸化c-Jun氨基末端活化蛋白激酶（p-JNK）和磷酸化p38（p-p38）在胚胎神经管上皮的表达变化.结果 p-JNK和p-p38的免疫阳性产物表达于胚胎神经管上皮细胞及其周围间充质细胞的胞浆中,高温后不同时间点胚胎神经管上皮细胞内的p-JNK和p-p38的表达量均较对照组减弱.结论 磷酸化JNK和p38参与了神经管的正常发育,其表达量降低可能是高温致NTD发生的重要途径之一.     

五种啮齿类动物mtDNA蛋白编码基因序列变化的比较

目的利用本实验室测定的中国地鼠、金黄地鼠和GenBank中田鼠、小鼠、大鼠的线粒体全基因组序列,比较分析五种啮齿类动物的mtDNA蛋白编码基因序列的变异,探讨其分子进化关系。方法将五种动物各自的13个蛋白编码基因分别连接成一个序列,用DNAstar-EditSeq分析软件计算每个序列的碱基长度和组成,计算蛋白编码基因的碱基和氨基酸的差异。以人为外群,基于连接在一起的13个蛋白编码基因的氨基酸序列,用MEGA4.0软件通过最大简约性法(MP)和非加权成对平均数法(UPGMA)构建进化树。结果在五种啮齿动物的13个蛋白基因序列中,A、T、C、G碱基的平均含量为32.4%、29.6%、26.2%和11.9%,中国地鼠mtDNA各蛋白编码序列以及其编码的氨基酸序列与其他物种相比,与金黄地鼠的相应序列差异最小,与大鼠mtDNA各蛋白编码序列以及其编码的氨基酸序列差异较大。分子进化树也显示中国地鼠和金黄地鼠的亲缘关系最近,与小鼠、大鼠存在的差异相对大。结论五种动物的碱基组成的百分比中显示G的相对缺乏,相互之间的进化关系与传统的分类地位基本吻合。     

白鹇的种下分类探讨

白鹇Lophura nycthemera是广布于我国南方和中南半岛的鸡形目鸟类,目前共记录有15个亚种。由于受河流、不适宜栖息地等环境的阻隔,白鹇现代分布区呈现部分连续、间断分布的地理格局,且成年雄鸟的上体羽色在亚种间具有明显变化,呈现复杂的羽色多态性。本文通过测量15个亚种的262号标本,从羽色和量度特征上对各个亚种进行了分组和比较。发现部分邻域分布的亚种在羽色和量度特征上相近或重叠,不具有稳定的可区分的外形特征,难以达到亚种的分类标准。进而指出了目前依赖于模式概念建立的种下分类系统存在的缺陷,提出了需要结合分子系统地理学方法从进化历史角度厘定白鹇种下分类的必要性。同时,对白鹇的起源与扩散、羽色演化和保护生物学等研究方向进行了展望。     

金双歧治疗婴幼儿病毒性腹泻疗效观察

目的观察和评价金双歧(双歧杆菌乳杆菌三联活菌片)治疗婴幼儿病毒性腹泻的临床疗效。方法将160例婴幼儿病毒性腹泻患儿随机分为观察组和对照组。观察组100例,服用金双歧片,对照组60例,服用蒙脱石散治疗,观察疗效和不良反应。结果观察组总有效率为92%,对照组总有效率为75%,2组差异有统计学意义(P<0.01)。结论金双歧治疗婴幼儿病毒性腹泻疗效显著,且未见不良反应。     

Observations on variation in skull size of three mammals in Israel during the 20th century

Among mammals, food availability, especially during the growth period, is a key predictor in determining final body size, and improved nutrition may lead to an increase in their body size. In Israel during the last century food availability for animals commensal with humans increased greatly, due to a 16-fold increase in the human population and the accompanying changes, such as a 135-fold increase in the area of irrigated agriculture and the availability of large quantities of organic garbage.Using museum material, we studied temporal changes in skull size of a sample of 89 red foxes (Vulpes vulpes Linnaeus, 1758), 108 golden jackals (Canis aureus Linnaeus, 1758) and 117 Cape hares (Lepus capensis Linnaeus, 1758) collected during the 20th century. Four measurements (condylobasal length, zygomatic breadth, the length of the upper cheek teeth row and the length of the mandible) were taken for each skull, and principal component analysis was used to combine the measurements into principal components.We found that skull size of the red fox increased significantly during the 20th century, possibly due to improved food availability from man-made resources such as agricultural produce and garbage. No temporal trend in body size was detected for the jackal and hare. These differences are discussed.