Nephelometric assay of staphylococal coagulase

Stutzenberger, Fred J. (Michigan State University, East Lansing), Charles L. San Clemente, and Dharam V. Vadehra. Nephelometric assay of staphylococcal coagulase. J. Bacteriol. 92:1005-1009. 1966.-Clotting of fibrinogen by staphylococcal coagulase was accompanied by an increase in light scattering; this property was used as a basis for a new nephelometric method. Reaction rates, which were now easily and precisely measured, were found to be directly proportional to coagulase concentration, when optimal conditions were maintained. These conditions included pH and concentrations of fibrinogen, coagulase-reacting factor, and sodium chloride in the reaction mixture. A standardized procedure for the assay is outlined, and a unit for the expression of activity is proposed.     

Relatedness between the coagulase gene 3'-end region and coagulase serotypes among Staphylococcus aureus strains

The 3'-end region of the coagulase gene from 22 strains of Staphylococcus aureus including 10 standard serotype strains was sequenced, and five subgroups with 4-8 tandem repeating units were distinguished among the tested strains. Phylogenetic analysis of the 3'-end region of the coagulase gene indicated that strains belonging to the same serotype were clustered in the same branch. A phylogenetic tree of the deduced amino acid sequences revealed that the C-terminal region might not be responsible for the epitope of the coagulase protein.     

临床分离凝固酶阴性葡萄球菌细菌谱

目的了解玉溪市人民医院临床分离凝固酶阴性葡萄球菌（CNS）的菌种构成和耐药特征。方法对该院近6年来临床分离的808株CNS作回顾性分析。结果808株CNS共有16种;表皮葡萄球菌、腐生葡萄球菌和溶血葡萄球菌占CNS的77.2%;甲氧西林耐药（MRCNS）和甲氧西林敏感（MSCNS）各占63.3%和36.7%;β-内酰胺酶阳性检出率为84.5%,且MRCNS显著高于MSCNS（χ^2=50.88,P〈0.01）;药敏结果：MRCNS除万古霉素、呋喃妥因和利福平外,青霉素、氨苄西林等12种临床常用抗菌药物的耐药率在50.6%-100%,显示了高度的耐药性和多重耐药。结论CNS在临床标本中的检出范围广、种类多,以表皮葡萄球菌、腐生葡萄球菌和溶血葡萄球菌为主,MRCNS的高度耐药和多重耐药形势严重,加强CNS的细菌学监测非常必要。     

儿童血液凝固酶阴性葡萄球菌的感染情况及耐药性分析

目的了解本院儿童血培养凝固酶阴性葡萄球菌（CNS）的感染率及其药物敏感情况,为儿科合理使用抗生素提供依据。方法对本院2006年1月至2007年12月间住院及门诊儿童血液培养的结果进行回顾性统计分析。结果在1265例儿童血培养中共检出CNS117株,其中表皮葡萄球菌41株（占35．0％）,人葡萄球菌27株（占23．1％）,溶血葡萄球菌21株（占18．0％）,其他凝固酶阴性葡萄球菌28株（占23．9％）;耐甲氧西林凝固酶阴性葡萄球菌（MRCNS）分离率为79．5％;MRCNS药敏结果显示多重耐药。结论CNS已成为儿童血液感染的重要致病菌,MRCNS检出率高且多重耐药,万古霉素、喹宁始霉素-达福普汀、呋西地酸是治疗MRCNS感染的首选药物。     

不同抗凝人血浆凝固酶检测的探讨

目的 了解3种不同抗凝人血浆检测血浆凝固酶的可行性及观察时间对结果的影响.方法 用3种不同抗凝人血浆及以不同菌液浓度作试管法凝固酶试验.结果 EDTA-K2抗凝血浆出现阳性慢,凝块大多较小,24 h内稳定性较好;枸橼酸钠抗凝血浆出现结果介于EDTA-K2、肝素抗凝血浆之间,结果最不稳定;肝素抗凝血浆出现阳性最快,但不够稳定;菌液浓度对出现阳性的早晚无影响.结论 3种抗凝人血浆在试管法凝固酶测定中使用时,出现阳性快慢不受菌液浓度影响,随时间延长溶解现象可能会增加,应掌握结果观察时间,以降低假阴性.