Molecular Genetics, Biochemistry And Therapy Of Pathogen

病原体的分子遗传学、生物化学和治疗

• 批准号: 6514010
• 负责人: John E Bennett
• 金额: --
• 依托单位: NATIONAL INSTITUTE OF ALLERGY AND INFECTIOUS DISEASES
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6514010
• 关键词: Candida; Candida albicans; Paramyxovirus; amphotericin B; antifungal agents; azoles; communicable disease transmission; cycloheximide; drug resistance; drug screening /evaluation; fluconazole; fungal genetics; gene expression; genetically modified animals; hematopoietic tissue transplantation; homologous transplantation; human subject; human therapy evaluation; laboratory mouse; microorganism disease chemotherapy; northern blottings; nucleic acid sequence; patient oriented research; regulatory gene; respiratory infections; stem cell transplantation

Project 1. Azole resistance in Candida glabrata. (1) Sequencing was completed in CgAP1, a transcriptional activator which we cloned from C. glabrata. Strong similarity was found to the Saccharomyces cerevisiae gene,YAP1, and the Candida albicans gene, CAP1, including presence of a basic, leucine-rich amino terminal sequence and cysteines in conserved positions at the carboxy-terminal end. Expression of the gene in Saccharomyces cerevisiae markedly decreased susceptibility to a diverse group of drugs, including fluconazole, diamide, 4-nitroquinolone oxide and cycloheximide, indicating that this gene regulates one or more drug efflux pumps and has functional similarity to CAP1. Northern analysis was performed on resistant and susceptible C. glabrata isolates from the same patient and having the same CHEF pattern. Whereas the ABC transporters, CgDR1 and PDH1 showed increased transcript abundance of both genes in the resistant isolate, CgAP1 transcript abundance was the same. This raises the possibility that alterations in the cysteine-rich domain may account for increased regulatory activity, rather than increased expression. (2) Studies with C. glabrata were completed in a murine infection model using p47-phox (-/-) knockout mice. Fluconazole 80 mg/kg daily, the maximum dose that can be administered parenterally, was not effective in treating mice infected with C. glabrata whereas amphotericin B and caspofungin acetate were effective. Susceptibility of the isolates to the three drugs was nearly identical in vitro and blood concentrations of fluconazole were far in excess of those achieved with the other drugs. Project 2. Studies in hematopoietic stem cell transplant recipients: A cluster of 12 cases of human parainfluenza virus 3 (HPIV3) occurred in April-July, 2000 among 64 patients who had received an allogeneic hematopoietic stem cell transplant in the NHLBI bone marrow transplant unit. Upper respiratory symptoms predominated but three patients had pneumonia. Exposure history and molecular analysis of the HPIV3 isolates found that both community acquired and nosocomial transmission had occurred. A chain of transmission was identified among 4 outpatients which extended to 2 hospitalized patients, one of whom died. Institution of control measures ended the outbreak after 11 weeks.

项目1。光滑念珠菌的唑类耐药。(1)CgAP 1是我们从C.光滑的强烈的相似性被发现的酿酒酵母基因，YAP 1，和白色念珠菌基因，CAP 1，包括存在一个基本的，富含亮氨酸的氨基末端序列和半胱氨酸在保守的位置在羧基末端。该基因在酿酒酵母中的表达显着降低了对不同药物的敏感性，包括氟康唑，二酰胺，4-硝基喹诺酮氧化物和放线菌酮，表明该基因调节一个或多个药物外排泵，并具有功能相似的CAP 1。用北方分析法对抗性和感病C. glabrata分离物来自同一患者并具有相同的CHEF模式。而ABC转运蛋白，CgDR 1和PDH 1显示增加的转录丰度的两个基因在耐药分离，CgAP 1转录丰度是相同的。这提出了这样的可能性，即富含半胱氨酸的结构域的改变可能导致调节活性增加，而不是表达增加。(2)研究C。glabrata在使用p47-phox（-/-）敲除小鼠的鼠感染模型中完成。氟康唑80 mg/kg/d（最大剂量）对感染C.光滑的，而两性霉素B和醋酸卡泊芬净有效。三种药物的敏感性几乎是相同的，在体外和氟康唑的血药浓度远远超过与其他药物实现的。 项目2.造血干细胞移植受者的研究：2000年4月至7月，在NHLBI骨髓移植单位接受异基因造血干细胞移植的64例患者中发生了12例人副流感病毒3型（HPIV 3）病例。上呼吸道症状占主导地位，但三名患者有肺炎。对HPIV 3分离株的暴露史和分子分析发现，社区获得性传播和医院内传播均已发生。在4名门诊病人中发现了一条传播链，该链延伸到2名住院病人，其中1人死亡。控制措施的实施在11周后结束了疫情。