Colonization of denture plaque by respiratory pathogens in dependent elderly

Objectives: Recently, there has been a resurgence of interest in the interactions between oral conditions and a number of prevalent systemic diseases. The morbidity and mortality of the dependent elderly that result from aspiration pneumonia have been recognized as a major geriatric health problem. The purpose of this study was to gain more information on the microflora of plaque on dentures and to assess the existence of oral infectious pathogens potentially causing the respiratory disease in the dependent elderly. Subjects and Methods: The denture bacterial flora of 50 dependent elderly were examined to identify microorganisms by the culture method. Results: 18 species of microorganisms were detected in denture plaque in this study. A variety of pathogens with the potential to cause respiratory infection pathogens colonized on the dentures of dependent elderly. Conclusion: The results of the present study revealed that bacteria that commonly cause respiratory infection colonized on the dentures of dependent elderly, suggesting that denture plaque may function as a reservoir of potential respiratory pathogens to facilitate colonization on the oropharynx.     

Determination of the copy number of the nuclear rDNA and beta-tubulin genes of Pneumocystis carinii f. sp. hominis using PCR multicompetitors

Multiple copies of a gene may lead to difficulty in the interpretation of typing results because polymorphism of the copies may wrongly lead to the conclusion that different types are present in a specimen. To determine the copy number per genome of the nuclear rDNA and beta-tubulin genes analyzed for the typing of Pneumocystis carinii f. sp. hominis, we developed a strategy based on the use of the same multicompetitor molecule in two different quantitative-competitive PCRs, one for the gene under study and the other for a reference single copy gene, allowing direct comparison of the results of both PCRs. Control experiments showed that the strategy was sensitive enough to detect duplication of a gene. The copy number of the nuclear rDNA operon was determined by amplification of the intron of the 26S rDNA gene and that of the beta-tubulin by amplification of the region surrounding the intron no. 6. The method was first tested on P. c. carinii, the special form commonly infecting rats. Pneumocystis c. carinii was found to contain a single copy of the rDNA operon. The method was then applied to P. c. hominis. The results confirmed that P. c. hominis genome contains a single copy of the nuclear rDNA and beta-tubulin genes.     

Nonparametric estimation for the three-stage irreversible illness-death model

In this paper, we present new nonparametric estimators of the stage-occupation probabilities in the three-stage irreversible illness-death model. These estimators use a fractional risk set and a reweighting approach and are valid under stage-dependent censoring. Using a simulated data set, we compare the behavior of our estimators with previously proposed estimators. We also apply our estimators to data on time to Pneumocystis pneumonia and death obtained from an AIDS cohort study.     

呼吸机相关性肺炎鲍氏不动杆菌感染的临床特征分析

目的：研究呼吸机相关性肺炎鲍氏不动杆菌感染的临床特征。方法：选取2010 年1 月到2015 年1 月我院收治的应用呼吸 机患者130 例,根据是否合并肺炎鲍氏不动杆菌感染将患者分为研究组（86 例）和对照组（44 例）,分析呼吸机相关性肺炎鲍氏不 动杆菌的临床特征,然后根据药敏实验选择应用药物进行治疗,并观察治疗效果。结果：呼吸机相关性肺炎鲍氏不动杆菌感染的 分布科室主要以ICU 为主,大约为76.74％,神经外科次之,大约为8.14％;研究组呼吸机应用时间（18.72± 3.15）天显著长于对照 组（6.18± 0.02）天,两组比较差异具有统计学意义（P＜0.05）;研究组经舒巴坦联合左氧氟沙星或者亚胺培南治疗后总有效率为 91.86％。结论：呼吸机相关性肺炎鲍氏不动杆菌多发生于ICU,且感染者呼吸机应用时间较长,联合治疗效果显著。     

重症肺炎患者干扰素-r、IL-6 和TNF-alpha含量变化研究

目的：探究重症肺炎患者干扰素-r、白细胞介素-6 和肿瘤坏死因子-alpha含量变化及其临床意义。方法：选取我院收治并确诊 为肺炎的患者103 例,根据病情不同,将其分为重症肺炎组52 例及普通肺炎组51 例,同时选取同期参加健康体检人群50 例,为 对照组。比较三组成员不同时间段干扰素-r、白细胞介素-6 和肿瘤坏死因子-alpha含量,重症肺炎组患者存活与死亡组上述因子含 量情况。结果：入院6 h 后,与对照组比较,重症肺炎及普通肺炎组干扰素-r、白细胞介素-6 及肿瘤坏子因子-琢含量较高P＜ 0.05,与普通肺炎组比较,重症肺炎组重症肺炎组干扰素-r、白细胞介素-6 及肿瘤坏子因子-alpha含量较高P＜0.05;入院24 h后,与 对照组比较,重症肺炎组干扰素-r、白细胞介素-6 及肿瘤坏子因子-alpha含量较高P＜0.05,普通肺炎组与对照组比较无差异P＞ 0.05;重症肺炎死亡组患者干扰素-r、白细胞介素-6 及肿瘤坏子因子-alpha含量较高P＜0.05。结论：干扰素-r、白细胞介素-6 以及 肿瘤坏死因子-alpha参与患者的免疫调节,可间接提示患者的病程发展,可作为判断病情程度的有利依据。     

重症肺炎患者PCT,WBC,CRP水平与预后的相关性分析

目的:探讨重症肺炎患者降钙素原(PCT)、白细胞(WBC)、C-反应蛋白(CRP)水平与疾病的相关性。方法:回顾性分析我院ICU收治的101例重症肺炎患者,患者均采取机械通气治疗,根据生存情况分为分为生存组与死亡组,另选取同期体检的正常人共40例作为对照组。在住院时、入院后第1 d、5 d以及转出ICU(或死亡时)抽取外周血检测血清PCT、WBC以及CRP水平,同时进行APACHEⅡ评分,并应用统计学分析方法进行数据的相关性分析。结果:1与正常人群相比,重症肺炎患者的PCT、WBC以及CRP显著升高,与死亡组同期比较,生存组PCT、WBC以及CRP较低,P0.05;2与死亡组同期比较,生存组APACHEⅡ评分较低,P0.05;3相关性分析结果显示WBC、CRP、PCT与APACHEⅡ评分呈正相关P0.01。结论:重症肺炎患者的血清PCT、WBC以及CRP水平升高明显,有利于判断重症肺炎病情,对评估预后具有一定的价值。     

Clinical applications of azithromycin microspheres in respiratory tract infections

Few adequately designed clinical trials have addressed optimal treatment duration in lower respiratory tract infections. Drugs possessing favourable pharmacokinetic and pharmacodynamic profiles may obtain early bacterial eradication allowing shorter treatment duration. This may be associated with a number of advantages including reduced resistance induction, increased compliance, lesser adverse events, and cost containment. Recently, a novel 2.0 g single dose of azithromycin microspheres has been compared with 7-day levofloxacin 500 mg or extended release clarithromycin in over 400 patients with community-acquired pneumonia. Clinical cure and bacteriological eradication rates, hospitalizations, and deaths were similar between azithromycin and comparators. Azithromycin 2.0 g microspheres proved as effective as 7 days of levofloxacin 500 mg in acute exacerbation of chronic bronchitis patients across all degrees of obstruction severity. In both settings Azithromycin microspheres obtained clinical cure in most patients harbouring macrolide-resistant Streptococcus pneumoniae strains. The drug was well tolerated in clinical studies and in healthy volunteers with modest and transitory adverse events. An undoubted advantage of single-dose azithromycin administration is the facility in ensuring that patients complete their prescribed course of therapy. A further advantage of single-dose therapy is the potential for use as directly-observed therapy, which may be useful in specific clinical conditions.     

阿奇霉素治疗小儿支原体肺炎的效果观察和安全性分析

目的观察大环内酯类抗生素阿奇霉素治疗小儿支原体肺炎的临床疗效,并对用药安全性进行评价。方法选择我院2012年6月至2014年10月呼吸科收治的96例小儿支原体肺炎患者,随机平均分为观察组和对照组。观察组给予阿奇霉素治疗,对照组给予红霉素治疗,观察两组的临床疗效和不良反应。结果观察组患者治愈37例,显效8例,无效3例,总有效率为93.75%;对照组治愈30例,显效9例,无效9例,总有效率为81.25%,治疗组疗效优于对照组,差异有统计学意义(P0.05)。治疗组患者平均退热、止咳、平喘、肺部啰音消失时间均短于对照组,平均住院时间和住院花费均少于对照组,差异有统计学意义(P0.05)。两组均偶见局部皮疹、注射部分疼痛等轻度不良反应,差异无统计学意义;观察组无胃肠道反应,对照组有4例胃肠道反应。结论阿奇霉素治疗小儿支原体肺炎能有效改善临床症状,较红霉素能提高治疗效果,缩短病程,且无严重不良反应,安全可靠,值得推广应用。     

Direct and indirect effects of anthropogenic bird food on population dynamics of a songbird

Anthropogenic bird foods are frequently credited with affecting avian population dynamics, but few studies have tested this assertion over broad spatial scales. Human-derived foods could directly impact population sizes or indirectly affect them by mediating the influence of another factor, such as disease. In 1994, a novel disease outbreak (mycoplasmal conjunctivitis) substantially reduced populations of the house finch (Haemorhous mexicanus) in the eastern United States, creating an opportunity to test whether bird feeding indirectly exacerbated or ameliorated the impacts of the disease. We assessed the effects of bird food availability on house finch populations using data from the National Survey on Fishing, Hunting, and Wildlife-associated Recreation and the Christmas Bird Count. House finch densities were positively related to the density of people providing food for birds prior to the spread of mycoplasmal conjunctivitis, suggesting that the availability of bird seed can limit the size of finch populations. Following the disease epidemic, house finch declines were greatest where the density of people feeding birds also fell dramatically. This pattern suggests that bird food could have a positive indirect effect on disease-related mortality. Our findings suggest that the collective actions of individual people have the potential to influence resource availability and population dynamics of wildlife in human-modified landscapes.     

肺炎链球菌去信号肽脂蛋白PsaA锌离子结合特性的初步表征

肺炎链球菌是细菌性肺炎的主要病原体。PsaA是各种肺炎链球菌共有的遗传保守的特异性表面金属结合脂蛋白。通过PCR扩增肺炎链球菌D39不含信号肽的PsaA基因片段,将其通过T4连接酶连接至含6His标签的表达载体PBAD/HisA中,转化表达宿主大肠杆菌Top-10后用L(+)-阿拉伯糖诱导重组蛋白的表达。重组蛋白经亲和镍柱纯化以后,用外切酶-重组肠激酶(REK)去除6His标签。感应偶合电浆质谱(ICP-MS)测得纯化的PsaA蛋白以1:1比例结合金属锌离子。进而,通过圆二色谱法分析金属离子的结合对蛋白二级结构中α-螺旋和β-片层含量的影响,荧光光谱研究蛋白结合锌离子的解离常数及结合当量,为进一步研究该蛋白在体外的金属结合特性及细菌的金属运输及毒力机制提供理论基础。