Influence of Bacterial Profiles in Cytokine and Clinical Features of Endodontic Disease

IntroductionWe verified the association between selected bacterial profiles and levels of cytokines, chemokines, and the expression of signs and symptoms of primary endodontic infection with apical periodontitis.MethodsSamples were collected from 21 root canals, and macrophages were stimulated for 24 hours. Tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, IL-10, IL-12p70, interferon gamma, and chemokine (C-C motif) ligand 2 (CCL2) were measured using cytometric bead array. We investigated the overlapping networks between cytokines and chemokines with regression analysis. Checkerboard DNA-DNA hybridization was used to assess 40 target bacteria species. Using factor analysis, bacterial species aggregated in 2 factors. The association of bacteria species–based factors on cytokine and chemokine levels and clinical features was estimated with regression analysis.ResultsA negative relationship between IL-10 (anti-inflammatory cytokine) and CCL2, TNF-α, and IFN-γ (proinflammatory cytokines) (all P < .05) was observed. CCL2 was positively correlated with TNF-α (P < .01). Thirty-eight bacteria species were detected in primary endodontic infection with apical periodontitis. The first bacteria species–based factor was associated with the size of the radiolucent area (coefficient = 15.42) and tenderness to percussion/pain on palpation (coefficient = 20.79). The second factor was associated with CCL2 levels (coefficient = 1.28).ConclusionsDifferent bacterial profiles can be differentially related to the expression of inflammatory proteins and the experience of clinical features.     

临床科室病原菌培养及耐药性

目的了解临床科室病原菌送检情况及病原菌耐药性,为临床疾病诊断和合理使用抗菌药物提供帮助。方法对2004-2005年医院20多个临床科室送检的病原菌培养标本,采用Microscan A/S-4细菌鉴定及药敏测试仪进行鉴定和药敏试验并对其结果进行统计分析。结果临床病原菌培养送检率低,且标本分散;送检标本以痰、脓、尿、血为主,占52.15%;各科室前3位优势病原菌共13种,内科感染的病原菌主要为肺炎克雷伯菌和大肠埃希菌,外科感染的病原菌主要为铜绿假单胞菌、鲍氏/溶血不动杆菌、阴沟肠杆菌、金黄色葡萄球菌,且耐药现象严重;鲍氏/溶血不动杆菌、阴沟肠杆菌仅对亚胺培南敏感;铜绿假单胞菌对哌拉西林/他唑巴坦、头孢他啶、阿米卡星较敏感,耐药率<40%,对亚胺培南耐药率>50%。结论铜绿假单胞菌、鲍氏/溶血不动杆菌、阴沟肠杆菌耐药现象严重,临床必须高度重视,提高病原菌送检率。     

新生儿败血症血培养的病原学分析

目的了解新生儿败血症感染菌株的细菌分布图、细菌的耐药性和它们在五年中的变化趋势。方法回顾性调查中南大学湘雅三医院近五年间新生儿败血症血培养分离的细菌株。结果在2864例标本中，细菌培养阳性为541例。大多数败血症为出生后1周的早期发作（58、6％），革兰阴性杆菌（55．3％）比革兰阳性球菌（44.7％）多见。但金黄色葡萄球菌是最常见的菌株（35，5％）。五年中，革兰阳性和革兰阴性菌的感染率没有很大变化。但是，不动杆菌的感染率在五年中呈现稳定持续的升高趋势。结论从近五年的结果来看，对革兰阴性菌最有效的抗生素是阿米卡星，对金黄色葡萄球菌和铜绿假单胞菌最有效的是奈替米星和环丙沙星。     

MONITORING OF DIALYSIS WATER SYSTEMS — IS THERE A NEED FOR INCREASED SAMPLING?

Water quality is one of the most important aspects of ensuring a safe and effective delivery of haemodialysis. An extensive microbiological survey of several water systems highlighted a contamination problem which routine sampling had failed to detect. Current guidelines suggest that samples for microbiological and endotoxin analysis should be taken from the outlet of water treatment plant and points expected to have the highest bacterial load, normally the end of the distribution loop and connections to the dialysis machines, where the flow is at its lowest. The survey extended sampling to include a large number of machine connection points. Four systems were investigated. The samples from routine test points generally returned results within our operational limits (<10 CFU/ml and <0.06 IU/ml). However, results from several machine connection points exceeded these limits by a large margin. Several disinfection cycles were required in order to achieve results in keeping with our operational limits. The conclusion is that sample results from the end of the distribution loop may give a false sense of security by not indicating a contamination problem at the machine connection points. Increasing the number and frequency of machine connection points tested should provide greater security in detecting contamination and allow for remedial action at an earlier stage.     

一次性注射器“满手握”法对药液细菌污染的观察

目的：观察一次性注射器的“满手握”法对无菌药液细菌污染的影响。方法：随机抽取十名采用“满手握“法持一次性注射器的护士所配制的药液各一瓶做细菌培养，观察培养阳性率。结果：10次细菌培养均阴性。阳性率为零。结论：用”满手握“法持一次性注射器抽吸药液可能不会造成无菌药液的细菌污染。     

部分致病菌耐药性调查分析

由于广谱抗生素在临床使用日在增多，细菌的耐药性已成为严重问题。滥用抗生素产生菌群失调，二重感染明显增多，促进耐药菌株的产生。因此，合理使用抗生素是目前至关重要的工作。     

产超广谱β-内酰胺酶的临床菌株脉冲场凝胶电泳特性

目的 研究临床分离产超广谱β－内酰胺酶（ESBLs）肺炎克雷伯菌、大肠埃希菌的同源性。方法 对我院临床分离的产ESBLs的肺炎克雷伯菌13株、大肠埃希菌35株，共48株菌，进行脉冲场凝胶电泳（PFGE）。结果 在48株产ESBLs试验菌株中，有2株大肠埃希菌被证明是亲缘关系密切的同源菌。结论 PFGE是研究临床菌株流行情况、分析菌株间同源性理想的分子分型方法。     

全密闭式输液方式的探讨

目的探讨全密闭式输液方式的安全性、有效性. 方法采用对临床上空气污染的调查及半密闭式输液过程中空气进入液瓶中造成的污染因素. 结果采用全密闭式输液方式,有效地杜绝空气中细菌微粒对液体的污染,提高输液的安全有效. 结论应积极推广全密闭式输液方式在临床上的应用.     

GTX(4) imposters: characterization of fluorescent compounds synthesized by Pseudomonas stutzeri SF/PS and Pseudomonas/Alteromonas PTB-1, symbionts of saxitoxin-producing Alexandrium spp.

Saxitoxins, the etiological agent of paralytic shellfish poisoning, are synthesized by dinoflagellates and cyanobacteria. Several reports indicate that bacteria are capable of saxitoxin synthesis. Two bacterial strains were isolated from saxitoxin-producing dinoflagellates, Alexandrium tamarense and A. lusitanicum (=Alexandrium minutum), and grown under a variety of culture conditions including those previously reported to induce saxitoxin synthesis in bacteria. Five fluorescent compounds were accumulated by the bacteria that had HPLC-FLD retention times similar to a reference standard of GTX(4), one of the saxitoxin congeners. However, we were unable to detect GTX(1), the epimeric partner of GTX(4), in the bacterial samples. The GTX(4) standard was hydrolyzed by NaOH/heat treatment but four of the bacterial compounds were stable. Unlike GTX(4), none of the five bacterial compounds were detectable by HPLC-FLD following electrochemical oxidation. The fluorescence emission spectrum of each of the five bacterial compounds was unique and readily discernable from the spectrum of GTX(4). None of the samples containing the putative GTX(4) toxin yielded positive results when analyzed by a 3H-saxitoxin receptor-binding assay for saxitoxin-like activity. We cannot rule out the possibility that these bacteria produce saxitoxins, however, our data clearly demonstrate that they accumulate at least five different fluorescent compounds that could be easily mistaken for GTX(4). We conclude that these five fluorescent compounds are GTX(4) imposters and that fluorescence scanning and chemical/heat stability should, at a minimum, be incorporated into HPLC-FLD protocols for identification of saxitoxins.     

福建沿海海域细菌种类和分布的调查

[目的]了解我国福建沿海海域细菌的种类及分布情况。[方法]海水经增菌培养、细菌分离，进行细菌学鉴定。[结果]102份海水共分离出细菌34种203株，其中弧菌科159株(78．33％)，肠杆菌科24株(11．82%)，非发酵菌15株(7．39％)，革兰阳性球菌3株(1．47％)，厌氧菌2株(0．99％)。[结论]此项调查对于海水细菌感染的防治研究，提供了理论依据。