Tuberculosis surveillance in immigrants to Manitoba.

Despite a decrease in the incidence of tuberculosis in Canada over the last decade, the proportion of cases in people not born in Canada has increased. To determine the prevalence of active tuberculosis at the first surveillance clinic visit and the incidence of the disease over a 2-year to 6-year follow-up period, we reviewed the records of all 523 immigrants admitted to Manitoba between 1981 and 1985 who were placed under surveillance. Of the 523, 429 (82%) were seen at least once in the clinic. Among the 429, active tuberculosis was diagnosed at the first visit in 12 (3%) and during the follow-up period in 7 (2%). The relative risk of tuberculosis was 4.5 times higher for immigrants under surveillance than for those not under surveillance. Of the 483 immigrants who were to be seen in Winnipeg 232 (48%) were noncompliant: 94 were not seen at any time, and 138 did not attend for the full follow-up period. Active disease was not reported to have developed in any of the noncompliant subjects. Noncompliers were significantly older than compliers (p less than 0.005), and variations in compliance were noted according to region of origin. Further attempts to improve compliance with surveillance without resorting to punitive measures are indicated.     

Multiple drug resistance genes in malaria -- from epistasis to epidemiology

A decline in our ability to successfully treat patients with malaria infections of the parasitic protozoan Plasmodium falciparum with cheap quinoline drugs has led to a huge escalation in morbidity and mortality in recent years. Many approaches have been taken, including classical genetics, reverse genetics and molecular epidemiology, to identify the molecular determinants underlying this resistance. The contribution of the P. falciparum multidrug resistance gene, pfmdr1, to antimalarial resistance has been a source of controversy for over a decade since it was first identified. In the current issue of Molecular Microbiology, Sidhu and colleagues use powerful reverse genetics to demonstrate the importance of commonly occurring alleles of pfmdr1 in conferring resistance to the second-line drugs quinine and sensitivity to the new alternatives mefloquine and artemisinin. They also elegantly highlight the importance of genetic background and epistasis between pfmdr1 and other potential modulators of drug resistance. Such molecular knowledge will facilitate surveillance/monitoring and aid the development of strategies for the reversal of resistance.     

Breast-feeding promotion in Manitoba. Committee on Breast-feeding,Manitoba Pediatric Society.

During the International Year of the Child the Manitoba Pediatric Society undertook professional and public education activities to promote breast-feeding in that province. The objective was a 100% increase in the proportion of mothers who breast-fed their infants for 2 months or longer. Surveys conducted before and after the campaign showed no significant increase in the rate of breast-feeding either at the time of hospital discharge or 2 months later. The infants of Winnipeg residents were more likely to be breast-fed than those of women living on Indian reservations or in any other part of the province (termed "rural"). The rate of bottle-feeding was significantly greater among infants of young unmarried mothers. Future programs to promote breast-feeding should be longer and more intensive, should be directed to the young, to rural residents and to Indian women, and should focus on social and emotional factors as well as nutrition and health benefits.     

Pleiotropic drug resistance in cystic fibrosis fibroblasts: increased resistance to cyclic AMP.

In previous studies, cystic fibrosis (CF) fibroblasts were demonstrated to be resistant to the cytotoxic effects of ouabain, dexamethasone, and the sex hormones, dihydrotestosterone, 17beta-estradiol, and progesterone. We now show that CF fibroblasts also exhibit greatly increased resistance to the cytotoxic effects of exogenous dibutyryl cyclic AMP (cAMP), as well as to isoproterenol and theophylline, drugs which are known to increase endogenous levels of cAMP. CF cells were also shown to have normal amounts of (3H)cAMP binding to protein kinase as well as normal amounts of cAMP-stimulated protein kinase activity. Phosphodiesterase in CF cells was also found to be stimulated by cAMP to the same degree as in normal cells. These findings suggest that there is no detectable protein kinase deficiency in CF cells. cf cells thus appear to be unlike some cAMP-resistant mutants described by others which are defective in protein kinase activity and cAMP regulation of phosphodiesterase levels. The cross-resistance of CF fibroblasts to ouabain, steroid hormones, and cAMP may provide a unique opportunity to study the biochemical events involved in the metabolism of these drugs as well as the basic biochemical defect in a common human genetic disease.     

Mobilization of plasmid-borne drug resistance determinants for transfer from Pseudomonas aeruginosa to Escherichia coli.

Summary Two- and three-point extranuclear crosses have been carried out via heterokaryons involving the three extranuclear mitochondrial markers of Aspergillus nidulans: (oliA1), (cs67) and (camA112). All three markers appear to be located on a single functional mitochondrial genome. Recombination between all three pairs of extranuclear markers appears to be equally frequent, suggesting a lack of genetic linkage. An important feature of these results is the variable and often marked non-equality of frequency of reciprocal classes of recombinants.     

2014—2015年大连市伤寒沙门菌耐药性及分子分型研究

目的 了解大连市伤寒沙门菌的药物敏感情况及同源性特点,为临床用药和疾病预防提供科学指导。方法 选择15种抗生素、运用微量肉汤稀释法对65株伤寒沙门菌进行抗生素敏感试验;采用脉冲场凝胶电泳（PFGE）法进行聚类分析。结果 65株伤寒沙门菌对阿奇霉素100.00%敏感,对红霉素100.00%耐药,对其他13种药物有不同程度的耐药率（1.54%~73.85%）。发现1株多重耐药菌株。65株菌共产生41种PFGE带型,其中8株菌表现为同一型别。结论 大连地区临床分离伤寒沙门菌耐药形势严峻;聚类分析结果表明其PFGE型别较多,而且其中存在着优势菌株。     

Transferable drug resistance of Escherichia coli isolated from infant diarrhoea.

The resistance to several drugs was determined in 29 pathogenic strains of Escherichia coli (026, 055 and 0111) isolated from infant diarrhoea and 18 non-pathogenic E. coli strains isolated from the same individuals. Both pathogenic and nonpathogenic strains were resistant to at least 1 to 10 drugs, but only in four cases resistance patterns of the pathogenic strains were identical with those of non pathogenic ones. The majority of the strains were resistant to sulfonamide, tetracycline, ampicillin, carbenicillin, neomycin and kanamycin. The drug resistance (except the resistance to nalidixic acid and rifampicin) was associated with conjugative R-plasmids. Some of the tested strains carried two R-plasmids in one cell, being in hetero R-state.     

Trends in coronary artery bypass grafting in Ontario from 1981 to 1989.

OBJECTIVES: To determine the trends in overall and age-specific rates of coronary artery bypass grafting (CABG) in Ontario from 1981 to 1989 and to assess whether relative resource scarcity, as manifested in waiting lists, resulted in obvious age-related or sex-related changes in utilization. DESIGN: Computerized compilation of hospital discharge abstracts from the Hospital Medical Records Institute. All separations for every other year from Apr. 1, 1981, to Mar. 31, 1990, were included. Procedures rather than patients were the unit of analysis (repeat procedures were double-counted if associated with separate hospital admissions). SETTING: Ontario acute care hospitals offering CABG. PATIENTS: People aged 20 years and over who underwent one or more CABG procedures. RESULTS: The overall rate of CABG increased by 31% in the study period, plateauing only between 1983 and 1985. By 1989-90 the rate was 66.03 per 100,000. The highest annual increase in the rate was among people aged 65 to 74 years, at 17.61 procedures per 100,000, as compared with 4.64 per 100,000 among people 75 years and over. In 1989-90 those aged 65 and over represented 37% of the total caseload. The overall male:female ratio did not change significantly throughout the study period. CONCLUSIONS: Since the CABG utilization rate continues to increase in Ontario, recent waiting lists must be due to a disproportionate growth in demand. There was no convincing evidence of age-related or sex-related discrimination in allocating this limited resource. Supply-demand mismatch was driven above all by the continued increase in CABG use among elderly people.     

Antituberculous Therapy in Pregnancy: Risks to the Fetus

A total of 1,939 reported births to mothers who received isoniazid ethambutol, rifampin and streptomycin alone or in combination, for all or part of their pregnancies, were surveyed to determine teratogenicity of these agents. There was no significant increase in birth defects with isoniazid, ethambutol and rifampin, in contrast to the use of streptomycin which was associated with mild auditory and vestibular defects. Guidelines for the treatment of active tuberculosis in pregnancy are therefore established.     

2011～2013年血液分离葡萄球菌的临床分布及耐药性分析

目的了解临床各科发热患者（怀疑细菌感染）血培养中葡萄球菌分布及耐药性,为临床治疗提供参考依据。方法血培养采用BaeT／Alert3D全自动血培养仪（梅里埃）培养5d,采用MicroScanWalk—Away-96plus全自动微生物鉴定和药敏分析系统（西门子）进行细菌鉴定和药敏试验。结果血培养共检出葡萄球菌185株,检出最多的科室是ICU,耐甲氧西林金黄色葡萄球菌（methicillin—resistant Staphylococcus aureus,MRSA）检出率为30．4％,而耐甲氧西林凝固酶阴性葡萄球菌（methicillin—resistant coagulase-negative Staphylococci,MRCNS）的检出率高达80．7％。还检出了1株万古霉素中介的凝固酶阴性葡萄球菌。结论通过血培养检出葡萄球菌的耐药性分析发现,凝固酶阴性葡萄球菌对苯唑西林、氨苄西林、青霉素、红霉素的耐药率在70％以上,而对氯霉素、利福平、四环素的耐药率在30％以下,因此这三种药物应为我院应对凝固酶阴性葡萄球菌血流感染的常用首选药物。     

2009-2013年某三甲医院感染病原菌分布及耐药性分析

目的了解某三甲综合医院感染性病原菌的构成及细菌耐药性变迁,为抗菌药物的合理使用提供依据。方法对2009-2013年临床分离病原菌及其耐药性进行回顾性分析。结果革兰阴性杆菌对临床常用抗菌药物的耐药性,以氨苄西林、苯唑西林、头孢唑林的耐药率最高;对美罗培南、亚胺培南均较敏感,敏感率均为70%;克雷伯菌属对替卡西林耐药率为60%,不动杆菌属对头孢类和喹诺酮类耐药率很高。革兰阳性球菌对青霉素G、氨卞西林、苯唑西林、喹诺酮类的耐药率很高,都在50%以上。结论细菌耐药性仍是临床面临的严重问题,应加强对细菌耐药性的监测。