生命早期小鼠肠道菌群失调模型的建立

目的用头孢曲松溶液灌胃断乳期小鼠,建立小鼠生命早期肠道菌群失调的模型。方法将60只断乳期小鼠随机分为高剂量抗生素组、低剂量抗生素组和对照组,分别灌胃500 mg/ml、250 mg/ml头孢曲松溶液0.2 ml/次和相同体积的蒸馏水7 d,提取粪便DNA,用变性梯度凝胶电泳方法检测小鼠肠道菌群的变化,验证小鼠肠道菌群失调模型是否建立成功。结果实验d8时,高、低剂量抗生素组小鼠体重和对照组相比差异有统计学差异(F=56.42,P0.01),高、低剂量组小鼠粪便菌群多样性和丰富度降低。实验d0小鼠肠道优势菌群为Bacteroides stercoris、Lactobacillus murinus、Bacteroides caccae strain,实验d8优势菌群为Enterobacter sp.638、Ruminococcus torques、Pseudomonas stutzeri、Clostridium hathewayi。结论应用头孢曲松灌胃断乳期小鼠7 d,小鼠发生腹泻,小鼠肠道菌群多样性降低,肠道优势菌群发生改变。本研究成功建立断乳期小鼠肠道菌群失调模型。     

嗜酸乳杆菌对抗生素诱导小鼠肠道菌群失调的作用

目的:用传统的微生物培养法和无需预先培养的PCR-变性梯度凝胶电泳(DGGE)法,分析嗜酸乳杆菌对经头孢曲松处理后的小鼠肠道菌群的效果影响. 方法: SPF级雌性BALB/c小鼠随机饮用头孢曲松水溶液5 d,造成小鼠抗生素相关性菌群失调模型后,自然恢复组灌服等渗盐水;治疗组灌服嗜酸乳杆菌菌液(108CFU/mL),处理7 d后,对各组小鼠进行解剖,并取其盲肠内容物,运用活菌计数和PCR-DGGE技术,分析抗生素对小鼠盲肠内细菌的影响和嗜酸乳杆菌对已失调的肠道菌群的调整作用. 结果: 经头孢曲松处理后,使小鼠肠道内乳杆菌和双歧杆菌数量减少,肠球菌异常增殖,与正常对照组比有极显著差异;嗜酸乳杆菌的治疗使乳杆菌和双歧杆菌的数量得到恢复,同时肠球菌数量也降至正常水平;抗生素处理使优势菌群发生改变,菌群多样性减少,与正常对照组相比有极显著差异;灌服嗜酸乳杆菌后,菌群多样性指数回升至正常水平,与抗生素处理组及自然恢复组比较有显著性差异,而与正常对照组比较无显著性差异. 结论: 嗜酸乳杆菌对头孢曲松引起的肠道菌群失调具有调整作用;与传统微生物培养法相比,PCR-DGGE法是一种快速、有效并能直观反映整个微生态动态变化的分子生物学方法.     

益生菌在儿童抗生素相关性腹泻中的预防作用研究

目的观察益生菌在儿童抗生素相关性腹泻中的预防效果。方法选取2014年1月-2016年6月采用抗生素治疗的下呼吸道感染患儿60例,根据治疗措施分为对照组30例和观察组30例。对照组采用蒙脱石散、补液、维持电解质平衡等常规方法治疗,观察组采用益生菌治疗,采用荧光定量PCR方法检测患儿肠道菌群,并比较两组患者临床疗效及肠道菌群变化情况。结果观察组患儿治疗后腹泻持续时间为(2.84±0.98)d,对照组为(3.96±1.03)d,差异有统计学意义(P0.05);观察组患儿抗生素使用时间为(5.94±1.10)d,对照组为(10.25±2.51)d,差异有统计学意义(P0.05);观察组患儿大便次数恢复时间、大便性状改变时间均短于对照组(P值均0.05);观察组治疗后患儿肠道菌群双歧杆菌、乳杆菌菌群数均高于对照组(P值均0.05),大肠杆菌菌群数低于对照组(P0.05)。结论与常规方法治疗相比,下呼吸道感染患儿采用益生菌治疗效果更理想,能稳定肠道菌群,减少婴幼儿腹泻持续时间,值得推广应用。     

双歧杆菌对严重烧伤患者美罗培南应用后肠菌群的调节

目的探讨双歧杆菌对烧伤患者大剂量应用美罗培南后,紊乱肠菌群调整作用.方法严重烧伤患者23例应用美罗培南(6 g/d)7 d后, 随机分为治疗组(n=11)和对照组(n=12);双盲法给予双歧杆菌悬液和生理盐水(100 ml/d),疗程5 d;分别于美罗培南应用前及用后0、1、3、5 d,常规方法检测粪便中双歧杆菌、真菌、大肠埃希菌量.结果美罗培南应用7 d,肠道菌群中双歧杆菌量骤减近100倍,真菌数激增100倍;双歧杆菌治疗1 d,肠道双歧杆菌数增加100倍,3 d后真菌量减少约25倍;对照组在停用美罗培南后5 d 肠道菌群始基本恢复;腹泻患者口服双歧杆菌后3 d肠道菌群恢复,对照组5 d恢复.结论长期大剂量应用美罗培南可导致肠道菌群紊乱,停药后外源性补充双歧杆菌能较快恢复肠道生态,治愈抗菌药物相关性腹泻.     

甲壳低聚糖对抗生素脱污染小鼠肠道菌群的影响

目的观察甲壳低聚糖对抗生素脱污染小鼠肠道菌群的影响,为进一步开发壳聚糖提供理论依据.方法用盐酸林可霉素复制肠道脱污染小鼠动物模型,将模型小鼠随机分为治疗组和对照组,治疗组灌服甲壳低聚糖600mg@kg-1@d-1,对照组灌服等体积蒸馏水.7天后分析肠道菌群.结果模型小鼠治疗组肠道菌群基本恢复正常,与对照组相比差异具有显著性意义(P＜0.05).结论甲壳低聚糖对小鼠肠道菌群失调具有一定的调整作用.     

高通量测序技术分析壳寡糖对小鼠肠道菌群的影响

目的研究壳寡糖对小鼠肠道菌群的影响。方法利用诺氟沙星灌胃建立肠道微生态失调小鼠模型,然后用壳寡糖对昆明小鼠每天进行灌胃,连续灌胃14d后,在无菌条件下采集各组小鼠盲肠内容物,提取基因组DNA,对样本的16S rDNA基因V3-V4区进行PCR扩增,采用Illumina-Miseq高通量测序平台测序,并对各样本进行生物信息学分析。结果体外实验结果显示,壳寡糖能显著促进乳杆菌的生长,抑制大肠杆菌的生长,且呈浓度剂量依赖。OTUs结果显示,利用抗生素处理后,小鼠肠道菌群的数量与对照组相比明显减少,但壳寡糖能增加和恢复小鼠肠道内的菌群数量。肠道菌群Alpha多样性和Beta多样性分析结果显示,壳寡糖能增加小鼠肠道菌群的丰富度和多样性,可恢复抗生素对小鼠肠道菌群平衡造成的破坏。在属水平上对样品进行菌群种类和丰度分析的结果显示,4组样本在菌群种类和丰度上均存在较大的差异。Azospira、Bacteroides(拟杆菌属)、Lactobacillus(乳杆菌属)和Alistipes(另枝菌属)在4组样本中的菌属序列数目变化最为显著。其中壳寡糖组能够抑制有害菌Azospira的生长和繁殖,提高肠道益生菌群Bacteroides、Lactobacillus和Alistipes的种类和丰度,而自然恢复组与之相反。结论壳寡糖能够提高小鼠肠道益生菌群的种类和丰度,可对抗生素造成的肠道菌群紊乱具有显著的改善和恢复作用。     

乳杆菌对幼年小鼠肠道菌群紊乱的缓解和恢复作用

目的探索乳杆菌对头孢曲松诱导的小鼠幼年期肠道菌群紊乱的缓解和恢复作用,以及对机体免疫的可能影响。方法 48只4周龄Balb/c雄性小鼠按体重随机分为空白对照组、抗生素组、泡菜直投菌组(PC)和鼠李糖乳杆菌组(LGG),每组12只。实验共计4周,第1周对照组、抗生素组、PC组和LGG组分别灌胃生理盐水、头孢曲松(40 mg)、头孢曲松和PC菌悬液(10⁹ CFU)、头孢曲松和LGG菌悬液(10⁹ CFU),之后3周对照组和抗生素组不予灌胃,PC组和LGG组继续灌胃菌悬液。每3天测一次体重。每周收集一次粪便,二代测序分析粪便细菌的群落多样性和结构变化。实验第4周处死小鼠,采用实时荧光定量PCR法测定脾脏中白细胞介素-6(interleukin-6, IL-6)、IL-12和肿瘤坏死因子-α(tumor necrosis factorα, TNF-α)的mRNA表达水平。结果经抗生素灌胃的3组小鼠体重均低于空白对照组(P<0.05),PC组在第18 d首先恢复至正常水平,第21 d时抗生素组和LGG组也得到恢复。菌群多样性分析发现,投用抗生素...     

美沙酮对小鼠肠道菌群的影响

目的 通过研究美沙酮对小鼠肠道菌群的影响,探讨美沙酮与机体疾病发生的关系。 方法 将75只小鼠随机分为三组,分别用美沙酮、燕麦β-葡聚糖和生理盐水进行灌胃,28 d后收集小鼠粪便,提取细菌基因组DNA,应用实时荧光定量PCR法对6种细菌进行定量。 结果 美沙酮组总肠道菌群(9.93±0.16 vs. 9.78±0.17)、拟杆菌属(8.84±0.41 vs. 8.46±0.54)、大肠杆菌(7.08±0.21 vs. 6.86±0.05)数量均显著高于生理盐水组(P<0.05)。 结论 美沙酮对小鼠肠道菌群有一定影响,能使小鼠粪便中总肠道菌群、拟杆菌属、大肠杆菌数量增加,肠道微生物定植抗力减弱。     

益生菌预防婴幼儿抗生素相关性腹泻及对肠道菌群的影响

【目的】探讨益生菌对婴幼儿期感染性疾病患儿抗生素应用中腹泻的预防作用及肠道菌群的变化。【方法】89例应用抗生素治疗的下呼吸道感染患儿随机分成两组,一组(益生菌组)同时服用双歧杆菌三联活菌,另一组不用任何微生态制剂为对照组,比较两组腹泻的发生率。分别在抗生素给药前及给药后第3、6 d采集粪便,用荧光定量PCR的方法检测肠道菌群的变化。【结果】44例益生菌组患腹泻5例(发生率为11.3%),45例对照组患儿患腹泻21例(发生率为46.6%)。益生菌组患儿腹泻平均时间(1.30±0.24)d,对照组患儿腹泻平均病程(2.10±0.33)d。抗生素治疗过程中,肠道菌群出现明显改变,益生菌组抗生素治疗后双歧杆菌、乳酸杆菌及大肠杆菌数量较稳定,明显高于对照组(P<0.01)。【结论】益生菌能通过稳定肠道菌群而预防婴幼儿抗生素相关性腹泻。     

肠道微生态制剂在结直肠术后病人中的应用

目的:对结直肠手术后病人应用肠道微生态制剂治疗的效果进行评价. 方法:前瞻性、单盲、随机、对照临床试验.将32例结直肠中等以上手术的病人,随机分为试验组和对照组,每组各16例.试验组病人于术后第3天给予肠内营养 双歧杆菌/嗜酸性乳杆菌/粪链球菌(菌品名:金双歧),每天2次,每次4片,直至出院.对照组只给予肠内营养支持.观察病人术前及术后4～8 d的胃肠道症状、生命体征、粪便性状及量和菌群比例等. 结果:①胃肠道症状:两组病人术后恶心、呕吐、肠鸣音恢复等差异均无显著性意义(P＞0.05),总腹胀天数、总腹痛天数在两组间差异有显著性意义(P＜0.05).②腹泻及腹泻评分:两组病人在术后第6天腹泻例数差异有显著性意义(P＜0.05),总腹泻天数、总腹泻人数两组间差异有显著性意义(P＜0.05).两组病人腹泻评分在术后第6天有显著性意义.③菌群比例:试验组病人菌群比例(杆菌/球菌)术后3次均比对照组高,术后第2次监测,两组间差异有显著性意义(P＜0.05). 结论:在结直肠术后病人中,应用肠道微生态制剂可改善病人胃肠道症状、减轻腹泻严重程度和纠正肠道菌群失调.     

Calcium intake in the elderly: validation of a dietary questionnaire

Epidemiological studies of calcium and osteoporosis have been hampered by the lack of a suitable tool for assessing calcium intake. This report describes a new frequency and amount questionnaire for measuring present and past calcium intake in the elderly. The validity of the questionnaire was tested against two commonly used standards of dietary assessment, five-day duplicate diets and seven-day weighed dietary inventories. The resulting correlation coefficients were, respectively, r = 0.76 and r = 0.69, while that for repeatability was r = 0.84. Furthermore, the questionnaire categorized subjects into thirds of the distribution of intake with almost no gross misclassification. It is suggested that the present findings may be extended to the majority of normal, healthy elderly subjects, implying wide application for the questionnaire in the assessment of calcium intake in the elderly.     

The occurrence of antimicrobial substances in toilet,sink and shower drainpipes of clinical units: A neglected source of antibiotic residues

Antibiotics represent one of the most important drug groups used in the management of bacterial infections in humans and animals. Due to the increasing problem of antibiotic resistance, assurance of the antibacterial effectiveness of these substances has moved into the focus of public health. The reduction in antibiotic residues in wastewater and the environment may play a decisive role in the development of increasing rates of antibiotic resistance. The present study examines the wastewater of 31 patient rooms of various German clinics for possible residues of antibiotics, as well as the wastewater of five private households as a reference.To the best of our knowledge, this study shows for the first time that in hospitals with high antibiotic consumption rates, residues of these drugs can be regularly detected in toilets, sink siphons and shower drains at concentrations ranging from 0.02?μg·L^?1 to a maximum of 79?mg·L^?1. After complete flushing of the wastewater siphons, antibiotics are no longer detectable, but after temporal stagnation, the concentration of the active substances in the water phases of respective siphons increases again, suggesting that antibiotics persist through the washing process in biofilms. This study demonstrates that clinical wastewater systems offer further possibilities for the optimization of antibiotic resistance surveillance.     

Self-reported health problems among Swedish miners one year after unemployment

Unemployment is considered to be a public health concern sincedeterioration in the health of the unemployed is often anticipated.However, for some groups, such as miners, unemployment mightimprove health due to a cessation of potentially harmful occupationalexposures. This study evaluates the health of 79 miners in oneSwedish iron-ore mine, and 226 age-matched controls from thegeneral population, during one year after the closure of themine. The participants received a questionnaire regarding medicalhistory and subjective symptoms at the beginning of the studyperiod, and after one year. Statistically significant negativeeffects on self-reported health attributable to unemploymentwere not found, although neuropsychiatric symptoms were morecommon among the unemployed miners. The miners reported a statisticallysignificant improvement in grip force (p=0.031). They had asignificantly higher prevalence of symptoms associated withmining related exposures when compared with the population controls;pain in the upper extremities [relative risk (RR)=2.27, 95%confidence interval (Cl)=1.44–3.59), back pain (RR=1.84;Cl=1.237–2.75), vasospastic disease of the fingers (RR=2.05;Cl=1.18–3.57) and obstructive respiratory symptoms (attacksof dyspnea and wheezing: RR=3.67; Cl=1.167–11.6).     

Excès de cas humains et animaux de tularémie en France au cours de l’hiver 2007–2008 : émergence ou phénomène isolé ?

Context

Tularemia is a zoonosis affecting humans and hares in France. We describe the results of surveillance in both species, in 2007 and 2008.

Methods

Human tularemia cases are mandatorily notifiable in France since 2003. In hares, surveillance relies on volunteer hunter associations in all districts of the country. Data from mandatory reports and volunteer surveillance in 2007/2008 were analyzed and compared with previous results.

Results

In 2007/2008, 144 cases were reported in humans and 117 cases in hares. This was a 100% increase compared to previous years. Human cases differed from those of previous years only by the frequency of contact with breeding animals. Human cases without any documented risk exposure were also more frequent.

Conclusion

An increase of tularemia cases occurred in 2007/2008 in both species. Complementary studies are needed to identify the species reservoir in France to understand the causes of this peak of cases.     

Occupational health hazards in mining: an overview

This review article outlines the physical, chemical, biological, ergonomic and psychosocial occupational health hazards of mining and associated metallurgical processes. Mining remains an important industrial sector in many parts of the world and although substantial progress has been made in the control of occupational health hazards, there remains room for further risk reduction. This applies particularly to traumatic injury hazards, ergonomic hazards and noise. Vigilance is also required to ensure exposures to coal dust and crystalline silica remain effectively controlled.     

Manufacture and use of nanomaterials: current status in the UK and global trends

This paper provides an overview of the production and use of nanomaterials (NMs), particularly in the UK. Currently, relatively few companies in the UK are identifiable as NM manufacturers, the main emphasis being the bulk markets in metals and metal oxides, and some niche markets such as carbon nanotubes and quantum dots. NM manufacturing in the UK does not reflect the global emphasis on fullerenes, nanotubes and fibres. Some assumptions have been made about the types of NM that are likely to be imported into the UK, which currently include fullerenes, modified fullerenes and other carbon-based NMs including nanotubes. Many university departments, spin-offs and private companies have developed processes for the manufacture of NMs but may only be producing small quantities for research and development (R&D) purposes. However, some have the potential to scale up to produce large quantities. The nanotechnology industry in the UK has strong R&D backup from universities and related institutions. This review has covered R&D trends at such institutions, and appropriate information has been added to a searchable database. While several companies are including NMs in their products, only a few (e.g. manufacturers of paints, coatings, cosmetics, catalysts, polymer composites) are using nanoparticles (NPs) in any significant quantities. However, this situation is likely to change rapidly. There is a need to collect more information about exposure to NPs in both manufacturing and user scenarios. As the market grows, and as manufacturers switch from the micro- to the nanoscale, the potential for exposure will increase. More research is required to quantify any risks to workers and consumers.     

深圳公立医院管理体制改革制度设计

深圳公立医院管理体制改革实行政事分开、管办分开,在理事会架构下按法定机构模式组建市医管中心,落实公立医院运营管理自主权.作者从当前公立医院管理体制的弊端入手,介绍了深圳市进行公立医院管理体制改革的基本思路及改革方案设计的主要举措,深入剖析了的改革方案的特点,并对改革效果进行了预测.     

Effects of nitrogen dioxide on red blood cells of rats: Changes in components of red cell membranes during in vivo exposure to NO2

Red cell membranes, prepared from red blood cells of rats exposed to 4, 10, or 20 ppm nitrogen dioxide (NO₂) for 1 to 10 days, were examined for evidence of changes in membrane components. Appreciable changes were not found in contents of phospholipid and cholesterol during exposure to 10 ppm NO₂. By contrast, protein content altered with the time of exposure. Moreover, changes in protein composition were observed by employing sodium dodecyl sulfate — polyacrylamide gel electrophoresis. Twenty-four-hour exposure to NO₂ at the concentration above 10 ppm resulted in a marked increase in the percentage of lysophosphatidylethanolamine (LysoPE) to the total phospholipids. The prolonged exposure to 10 ppm NO₂ gave rise to a further increase in LysoPE, whereas the percentage of phosphatidylethanolamine (PE) showed a gradual decrease. A 1-day exposure to 4.0 ppm NO₂ also caused an increase in sialic acid content and decreases in those of PE and hexose. In addition to contents of these components the percentage of LysoPE increased 5 days after exposure and the elevated values were maintained up to the end of exposure period. These results demonstrate that red blood cells in circulation exhibit different membrane properties in terms of lipid and carbohydrate composition during 10 days of exposure to 4.0 ppm NO₂.     

Investigating clusters in the workplace and beyond

Clusters of disease are common and occur in the workplace and in the general community. They often arouse considerable concern among the population. Investigations have sometimes lead to exciting new knowledge, but in general the investigation of clusters is difficult and often unrewarding, especially for community clusters. In the workplace, investigations are more likely to find associations and even new causes, but still many clusters remain enigmatic. Despite this, there are many reasons for investigating clusters, including allaying community concern and identifying uncontrolled exposures. A structure for investigating clusters in the workplace is suggested.