Dental plaque morphology as revealed by direct observation and by replicating techniques

Lie, T. Gusberti, F. Dental plaque morphology as revealed by direct observation and by replicating techniques.

The ability of four elastomer impression materials to reproduce details of bacterial plaque structures was studied by comparing areas of the replica models with corresponding areas of the replicated plaque. Plaque was grown on hydroxyapatite splint segments for 48 hours and replica models were made from three different resins. One of the resins, a methacrylate material, was not suited for this purpose due to its content of spherical particles. The polysulfide and polyether impression materials reacted with the heat curing epoxy resin, and less satisfactory results were obtained with cold curing epoxy resin. Best results were obtained by a combined use of low viscosity silicone impression materials and cold or heat curing epoxy resins as model materials. However, a considerable loss of detail occurred in the replica models compared with observations of plaque directly on splint surfaces. Outlines of individual bacteria could sometimes be seen in the models, but generally several cells seemed to fuse, and appeared lie small globular structures where cells and pellicle were difficult to distinguish. The bacterial colonization started near the gingival border of the surface, initiated by attachment of individual bacteria to the pellicle surface.     

Factors associated with effective reassessment of antibiotic therapy on day 3

Reassessment of antibiotic therapy (RA) after 3 days is constitutive of French antibiotic stewardship. This delay is required because of the need for clinical reappraisal and for obtaining microbiological data. Our aim was to determine the factors associated with an effective RA.     

医学临床标本细菌学检验质量控制措施探讨

目的 探讨医学临床标本细菌学检验质量控制措施,以提高病原学检测的准确性.方法 回顾性分析临床各科送检的细菌标本3800例,并进行统计分析.结果 标本检测质量优良为1844例,质量合格为1677例,总合格率为92.7％ (3521/3800).其中各类标本合格率前三位的是:脓肿及创伤组织标本(97.8％)、血液标本(96.9％)、生殖道分泌物标本(91.9％).标本检测不合格279例,不合格率为7.3％(279/3800).其中无菌操作不严格87例、标本取样位置不准确74例、标本采集量太少68例、没有及时送检36例、特殊标本未进行特殊处理14例.结论 严格遵守标本采集、运送操作规范,进行正确的标本采集、保存和处理是保证医学临床标本细菌学检测质量的关键.     

Multi-variate analysis of burns patients in the Singapore General Hospital Burns Centre (2003-2005)

The Burns Centre at the Singapore General Hospital (SGH) serves as a tertiary referral centre for burns management for Singapore's 4 million residents as well as the Southeast Asia region. Our study is a multivariate analysis of all burns patients admitted between 2003 and 2005. A total of 482 patients were admitted during this period with an average annual admission of 161. This represents a low incidence of 0.04 per 1000 admissions for the Singapore population. 13.3% of the study population were children, which is lower than previous studies. The mean age at admission was 35 years old and the male:female ratio was 1.9:1. We found a significant difference in age between the local and foreign patients, with the latter being younger. Our study demonstrated a 7.3% increase in cases of occupational burns. The bulk of our patients (57.3%) were directly admitted from SGH's Accident and Emergency Department. The patient characteristics of the various referral sources were found to be very different. GP referrals had significantly lower TBSA while overseas patients had significantly higher TBSA and longer length of stay. The mean and median time to admission was 3.05 days (+/-6.26) and 0 (0-60) day, respectively and the mean and median time to surgery was 7.33 days (+/-8.18) and 5 (0-22) days, respectively. The most common cause of burns was due to scalding. The mean extent of burn (TBSA) was 13.5% (+/-18.0), with significant correlation with the social background. Length of stay was dependent on the need for surgery. The overall mortality rate in this study population was 4.5%, with inhalation injury the main aetiological factor. In addition, the mean duration of the first surgery that patients undergo was significantly longer than that of the second one. This information will be useful for estimating operation times in the future. Finally, Acinetobacter baumannii was the most common bacteria in wound cultures. There is a need for periodic reviews of wound cultures in burns patients in order to modify the preventive and therapeutic strategies against these bacteria.     

临床细菌学在医院感染控制方面的作用

目的结合临床实践经验,探讨临床细菌学在医院感染控制方面的作用。方法通过查阅医院图书馆临床细菌学检验方面的档案,分析并探讨临床细菌学在医院感染控制方面的作用。结果微生物检验水平直接关系到感染性疾病的诊治水平和医院感染控制水平。结论医院要加大力度,更好地发挥临床微生物检验工作者在医院感染控制中的作用。     

寒冷干燥环境下枪弹伤细菌学定量观察

目的:探讨寒冷干燥环境下火器伤细菌定量变化及感染发展过程与特征。方法:用40只兔的后肢制作成寒冷干燥环境下枪弹伤模型,对伤后1小时、3小时、6小时、12小时、24小时、48小时、72小时、96小时进行了大体观察和细菌学变化定量检测。结果:伤后24小时内伤道细菌缓慢增加,仅达10~4cfu/g,伤后48小时达引起感染的临界值10~5cfu/g,伤后72小时、96小时为10~6cfu/g,但仍未达10~8cfu/g,结果表明寒冷干燥环境对枪弹伤后伤道组织细菌量变化的影响非常大,寒冷干燥环境下枪弹伤感染速度及感染严重程度都明显低于常温条件下的枪弹伤。结论:寒冷干燥环境下火器伤的救治应有别于常温常湿条件,其早期伤道清创时限可适当放宽。     

肺结核病院内呼吸道感染的临床分析

目的 :研究肺结核病人院内呼吸道感染的临床流行情况及其相关危险因素。方法 :2 0 0 0年 1月至 2 0 0 3年10月实际出院的肺结核病人中符合院内呼吸道感染者逐一填写医院感染病例登记表 ,对表内资料进行回顾性分析。结果 :①肺结核病人院内呼吸道感染发生率 6 .0 %。高危人群为伴有慢性肺部疾患的老年人、肺部以纤维空洞、支气管扩张、肺不张为主要病理损害的肺结核患者。相关危险因素为住院时间长、反复住院、重症结核病所致营养状态低下、大量长期使用广谱抗生素。②铜绿假单孢菌及克雷伯氏杆菌属是本院呼吸道感染的主要致病菌 ,且合并真菌感染率高 ( 4 3.5% )。结论 :结核病人院内呼吸道感染是一个值得重视的问题     

高温高湿环境下颅脑火器伤细菌学改变的研究

目的探讨高温高湿环境下颅脑火器伤后脑组织清创的时机、方法及抗生素的应用。方法60只犬随机分为高温高湿(MME)组和常温常湿(OE)组,于火器伤后0、4、6、8、12、24h进行大体情况、细菌学定量和定性变化等指标的检测。结果脑肿胀、组织坏死和动物死亡时间,MME组均较OE组提前且更严重,细菌学定量检测MME组火器伤伤道细菌数在同一时间点比OE组高细菌定性检测两组弹道局部均为表面菌群血液中,,;OE组只有表面菌群,MME组除表面菌群外,还有肠道菌群。结论高温高湿环境下火器伤后细菌繁殖快感染不仅时间提前且严重肠道细菌容易入血因此对在高温高湿环境下处理火器伤更应强调,尽早合理的清创和早期使用广谱抗生素。