The microbiological profiles of saliva, supragingival and subgingival plaque and dental caries in adults with and without type 2 diabetes mellitus

INTRODUCTION: The relationships between suspected bacteria in saliva, yeasts in oral rinse, and supragingival and subgingival plaque versus root surface and coronal caries in adults with type 2 diabetes mellitus and a non-diabetic group were explored. METHODS: One-hundred and five patients with type 2 diabetes and 103 non-diabetic subjects were recruited; their periodontal status, plaque index and magnitude of root surface and coronal caries were assessed. Saliva and an oral rinse were cultured for mutans streptococci, lactobacilli and yeasts. Toothbrush samples of supragingival plaque and curette samples of subgingival plaque were assessed for 17 bacterial species using the checkerboard DNA-DNA hybridization method. RESULTS: Type 2 diabetes patients had significantly more severe periodontitis, a higher plaque index and a higher prevalence and magnitude of root surface caries than non-diabetic subjects. Significantly more diabetic subjects had higher levels of Treponema denticola, Prevotella nigrescens, Streptococcus sanguinis, Streptococcus oralis and Streptococcus intermedius in their supragingival plaque than non-diabetic subjects. No significant difference was found for the organisms in saliva, oral rinse and subgingival plaque between the two groups. After adjustment for diabetic status, root surface caries was associated with an increased count of mutans streptococci, lactobacilli and yeasts in saliva and of Streptococcus mutans in supragingival plaque samples. Coronal caries was only associated with lactobacilli and yeasts in saliva. CONCLUSION: The number of cariogenic organisms in saliva and oral rinse estimated by culture demonstrated a stronger association with both root surface and coronal caries compared to those 17 species assessed with the checkerboard method in supragingival and subgingival plaque.     

Bacterial community profiles of endodontic abscesses from Brazilian and USA subjects as compared by denaturing gradient gel electrophoresis analysis

This study compared the bacterial community profiles of the microbiota associated with acute apical abscesses from Brazilian and USA patients using denaturing gradient gel electrophoresis (DGGE). DNA was extracted from purulent exudate aspirates and part of the 16S rRNA gene was amplified by polymerase chain reaction and separated by DGGE. The resulting banding patterns, which were representative of the bacterial community structures in samples from the two locations, were then compared. Distinct DGGE banding patterns were observed from different samples. Ninety-nine bands with distinct positions in the gels were detected, of which 27 were found only in the USA samples and 13 were exclusive to Brazilian samples. Four of the 59 shared bands showed very discrepant findings with regard to prevalence in the two locations. Cluster analysis of DGGE banding profiles showed a great variability in the bacterial populations associated with teeth with abscesses regardless of the geographical location. Two big clusters, one for each location, were observed. Other clusters contained a mixture of samples from the two locations. The results of the present study demonstrated a great variability in the bacterial community profiles among samples. This indicates that the bacterial communities of abscesses are unique for each individual in terms of diversity. The composition of the microbiota in some samples showed a geography-related pattern. Furthermore, several bands were exclusive for each location and others were shared by the two locations and showed great differences in prevalence.     

Periodontal and oral microbiological status of an adult population undergoing haemodialysis: a cross-sectional study

OBJECTIVES: The aim of this cross-sectional study was to evaluate the periodontal status and oral microbiological patterns of a population with end-stage renal disease (ESRD), undergoing haemodialysis (HD). DESIGN: This was a cross-sectional study, involving 52 patients from the Nephrology Department and 52 matched control subjects. MATERIALS AND METHODS: The subjects had a periodontal clinical examination; subgingival plaque samples were taken and analysed using a semiquantitative polymerase chain reaction (PCR) test to detect Porphyromas gingivalis, Tannerella forsythia, Prevotella intermedia, Prevotella nigrescens and Actinobacillus actinomycetemcomitans. Subgingival plaque and saliva samples were studied for Candida and Enterobacteriaceae. MAIN OUTCOME MEASURES: Most of the 104 subjects had some degree of loss of periodontal attachment (LPA) > or =3 mm [11 (10.5%) had severe LPA; 16 (15.4%) moderate LPA; and 64 (61.5%) mild LPA]. Only 13 subjects (12.5%) presented good periodontal health. Results: No statistically significant differences were found between the HD patients and the control group regarding bleeding index, number of teeth, or percentage of LPA > or =3 mm. However, a statistically significant difference was seen in the degree of oral hygiene. CONCLUSIONS: On the basis of the findings presented here, we cannot associate ESRD with more severe periodontal destruction. Although HD patients presented a higher number of periodontopathic microorganisms than the matched controls, a prolonged duration of HD did not bear a statistically significant relationship with the percentage of sites with LPA > or =3 mm, specific microbiota or composition of biofilm.     

Early pulmonary infection, inflammation, and clinical outcomes in infants with cystic fibrosis

A thorough understanding of the early natural history of cystic fibrosis (CF) lung disease is critical for the development of effective interventions in the youngest patients. We assessed the evolution of pulmonary infection, inflammation, and clinical course among 40 infants over a 2-year period through annual bronchoalveolar lavage (BAL) for culture and measurements of pro- and anti-inflammatory cytokines, semiannual infant pulmonary function testing, and quarterly clinical evaluations. Both the prevalence of CF pathogens and their density in BAL fluid increased with age. Infants had neutrophilic lower airway inflammation and elevated IL-8 concentrations independent of whether CF pathogens were recovered. Total leukocyte and neutrophil densities and IL-8 concentrations increased with density of CF pathogens in BAL fluid, whether the isolated organism was P. aeruginosa or another pathogen. IL-10 concentrations were similar in CF subjects and non-CF historical controls. Infants generally had suboptimal growth (low weight and height percentiles) and obstructive lung disease (decreased expiratory flows and air trapping). Subjects from whom CF pathogens were isolated at > 10(5) cfu/mL had the worst air trapping and lowest Brasfield chest X-ray scores. Our findings provide a foundation for future studies of early intervention in CF lung disease, including antimicrobial and anti-inflammatory therapy.     

结核病房空气中结核分支杆菌检测方法研究

目的探索空气中结核分支杆菌检测的有效方法。方法选用ＬＷＣ－Ⅰ型空气微生物采样器，对菌阳肺结核病房进行空气采样，３０份采样标本分别用不同方法检测结核分支杆菌。结果聚合酶链反应（ＰＣＲ）阳性１４份，阳性率４７％；Ｓｏｕｔｈｅｒｎ转印杂交阳性１８份，阳性率６０％；动物接种实验组３０只豚鼠有２只结核分支杆菌培养阳性，另１只病理组织学检查阳性，而对照组１０只豚鼠脏器培养及病理组织学检查全部阴性；罗氏培养和ＢＡＣＴＥＣ快速培养均呈阴性。结论用空气采样的方法进行空气中结核分支杆菌的监测是可行的。ＰＣＲ和Ｓｏｕｔｈｅｒｎ转印杂交最敏感，动物实验也可提供有意义的参考。     

PBL和CBL在高职高专《医学微生物学》教学中的应用

为了提高《医学微生物学》的教学质量,增加学生的学习兴趣,培养学生的临床思维能力,以问题为基础的PBL和案例为中心的CBL相结合的教学方法引入教学中,根据病例精心编写教案,组织学生展开讨论,将PBL和CBL同时应用到高职高专《医学微生物学》教学中,取得较好的教学效果。     

层流GICU物体表面消毒方法的比较及菌群检测

目的比较两种消毒剂对层流综合重症监护病房（GICU）高频接触物体表面的抑菌效果,为层流GICU选择合理的物体表面消毒方法提供临床依据;了解物体表面细菌的污染情况,为预防控制感染提供理论依据。方法对层流GICU住院患者床档、床头桌的物体表面（常规消毒前）,采集样本做细菌培养、鉴定,以了解层流GICU物体表面菌群分布。分别采用含有效氯500 mg/L消毒剂（常规组）、伽玛TM消毒湿巾（对照组）对层流GICU床单位周围物体表面进行消毒,比较两种消毒方法在消毒后的抑菌率和物体表面细菌总数合格率。结果常规消毒前共采集200份物体表面样本,分离细菌87株,细菌污染率43.50%。检出革兰阳性菌68株（78.16%）,以棒状杆菌（18株,26.47%）、金黄色葡萄球菌（16株,23.53%）、表皮葡萄球菌（16株,23.53%）为主;革兰阴性杆菌19株（21.84%）,以鲍曼不动杆菌为主（12株,63.16%）。进行物体表面消毒后10 min的抑菌率,常规组为（94.89±7.72）%,对照组为（96.33±12.88）%,两组差异无统计学意义（P>0.05）;两组物体表面细菌总数合格率均为100%。结论定期对层流GICU住院患者床单位周围物体表面进行检测、消毒,并规范医护人员的操作及手卫生执行力,是切断细菌传播,预防医院感染简单、有效的方法。     

Physicochemical and microbiological stability of two news oral liquid formulations of clonidine hydrochloride for pediatric patients

Pediatric patients present changing physiological features. Because of the lack of land suitable for commercial management, pediatric specialties very often need to prepare extemporaneous formulations to improve the dosage and administration of drugs for children. Oral liquid formulations are the most suitable for pediatric patients. Clonidine is widely used in the pediatric population for opioid withdrawal, hypertensive crisis, attention deficit disorders and hyperactivity syndrome, and as an analgesic in neuropathic cancer pain. The objective was to study the physicochemical and microbiological stability and determine the shelf life of an oral solution containing 20?µg/mL clonidine hydrochloride in different storage conditions (5?±?3?°C, 25?±?3?°C, and 40?±?2?°C). Using raw material with excipients safe for all pediatric age groups, two oral liquid formulations of clonidine hydrochloride were designed (with and without preservatives). Solutions stored at 5?±?3?°C (with and without preservatives) were physically and microbiologically stable for at least 90?days in closed containers and for 42?days after opening. Two oral solutions of clonidine hydrochloride 20?µg/mL were developed for pediatric use from raw materials that are readily available and easy to process, containing safe excipients that are stable over a long period of time.     

关于现代病原生物学教学改革的探讨

病原生物学是必不可少的医学基础学科。为适应现代医学发展趋式,病原生物学的教学改革势在必行。本文结合本院实际,通过对病原生物学教学中所存在问题的分析,论述近年来所采取的相应教学改革措施及其所取得的成果。     

Evaluation of a semi-automated Seegene PCR workflow with MTB,MDR, and NTM detection for rapid screening of tuberculosis in a low-prevalence setting

In areas of low tuberculosis (TB) prevalence, laboratory diagnosis of TB may essentially cover non-tuberculous mycobacteria (NTM) in addition to Mycobacterium tuberculosis (MTB). In this study, a semi-automated PCR workflow distinguishing MTB and NTM (Anyplex™ MTB/NTMe, Seegene) and subsequently detecting MTB isoniazid/rifampicin resistance (Allplex™ MTB/MDRe, Seegene) was evaluated for replacing smear microscopy of acid-fast bacilli as the rapid screening method for TB. With 279 clinical samples, 47 cultures positive for MTB and 76 for NTM, the Anyplex™ MTB/NTMe assay and smear microscopy showed equal sensitivities (49.6% vs 50.8%, respectively) but Anyplex™ MTB/NTMe was more sensitive for MTB (63.8% vs 25.6%) than for NTM (40.8% vs 64.5%). Allplex™ MTB/MDRe showed a slightly higher sensitivity of 68.1% for MTB (32/47 positive, n = 222). Antibiotic resistance profiles were correctly identified for all MTB isolates (one MDR isolate). Specificity was 100% for both assays. Anyplex™ MTB/NTMe detected all the 18 NTM species present in the study. The analytical performance of the evaluated high-throughput workflow was relatively weak compared to culture but potentially adequate as a rapid screening method analogous to smear microscopy with additional differentiation between TB, MDR-TB, and NTM.