An overview of the evolution of overproduced esterases in the mosquito Culex pipiens.
Insecticide resistance genes have developed in a wide variety of insects in response to heavy chemical application. Few of these examples of adaptation in response to rapid environmental change have been studied both at the population level and at the gene level. One of these is the evolution of the overproduced esterases that are involved in resistance to organophosphate insecticides in the mosquito Culex pipiens. At the gene level, two genetic mechanisms are involved in esterase overproduction, namely gene amplification and gene regulation. At the population level, the co-occurrence of the same amplified allele in distinct geographic areas is best explained by the importance of passive transportation at the worldwide scale. The long-term monitoring of a population of mosquitoes in southern France has enabled a detailed study to be made of the evolution of resistance genes on a local scale, and has shown that a resistance gene with a lower cost has replaced a former resistance allele with a higher cost. (+info)
Is hospital care involved in inequalities in coronary heart disease mortality? Results from the French WHO-MONICA Project in men aged 30-64.
OBJECTIVES: The goal of the study was to assess whether possible disparities in coronary heart disease (CHD) management between occupational categories (OC) in men might be observed and contribute to the increasing inequalities in CHD morbidity and mortality reported in France. METHODS: The data from the three registers of the French MONICA Collaborative Centres (MCC-Lille, MCC-Strasbourg, and MCC-Toulouse) were analysed during two period: 1985-87 and 1989-91. Acute myocardial infarctions and coronary deaths concerning men, aged 30-64 years, were included. Non-professionally active and retired men were excluded. Results were adjusted for age and MCC, using a logistic regression analysis. RESULTS: 605 and 695 events were analysed for 1985-87 and 1989-91, respectively. Out of hospital cardiac arrests, with or without cardiac resuscitation, and 28 day case fatality rates were lower among upper executives in both periods. A coronarography before the acute event had been performed more frequently in men of this category and the proportion of events that could be hospitalised was higher among them. In both periods, the management of acute myocardial infarctions in hospital and prescriptions on discharge were similar among occupational categories. CONCLUSIONS: For patients who could be admitted to hospital, the management was found to be similar among OCs, as was the 28 day case fatality rate among the hospitalised patients. In contrast, lower prognosis and higher probability of being hospitalised after the event among some categories suggest that pre-hospital care and the patient's conditions before the event are the primary factors involved. (+info)
Incidence of acquired immunodeficiency syndrome (AIDS)-related Kaposi's sarcoma in the Aquitaine Cohort, France, 1988-1996. Groupe d'Epidemiologie Clinique du SIDA en Aquitaine.
OBJECTIVE: To assess secular trends of the incidence of Kaposi's sarcoma (KS) between 1988 and 1996 in the Aquitaine Cohort of human immunodeficiency virus type 1 (HIV1)-infected subjects (southwestern France). METHODS: Adults of both sexes of all HIV-transmission categories were included. We distinguished between incident and prevalent KS and in case of multiple acquired immunodeficiency syndrome (AIDS) defining illnesses between initial or subsequent KS. Only incident KS were considered for annual incidence rate calculation. RESULTS: Overall, 21.2% (356/1678) of homosexuals and 1.9% (58/3030) of the other patients were diagnosed with KS over time. Although there was a sharp decrease in 1996 for initial KS, the annual incidence rate of KS was stable over time in the overall cohort as well as in homosexuals (4.3% per year on the average for KS as an initial AIDS-defining illness and 2.1% per year for subsequent KS in homosexuals). The median CD4+ cell count at the time of diagnosis of KS was 56 per mm3 (78 for initial KS, 14 for subsequent KS), with no significant variation over time. CONCLUSION: In the Aquitaine Cohort, the annual incidence of KS has remained stable between 1988 and 1995 with a recent decline in 1996, only for initial KS, while case management of HIV-infected subjects changed drastically. (+info)
The PRIME study: classical risk factors do not explain the severalfold differences in risk of coronary heart disease between France and Northern Ireland. Prospective Epidemiological Study of Myocardial Infarction.
We are studying the contribution of risk and genetic factors, and their interaction, to the development of ischaemic heart disease (IHD) and other cardiovascular endpoints. The study is prospective, based in three centres in the south, east and north of France and in Northern Ireland. A total of 10,592 men aged 50-59 years were recruited from 1991 to 1993, and examined for evidence of IHD at baseline. Subjects are followed annually by questionnaire. Clinical information is validated from hospital and GP records. Demographic characteristics were similar in all four centres. Body mass index was highest in Strasbourg (mean 27.4 kg/m2 vs. 26.3 kg/m2 in Toulouse and Belfast), but total cholesterol, triglyceride and fibrinogen were highest in Belfast. In Belfast, 6.1% reported having had a coronary angiogram, compared to 3.0% in Toulouse. Conversely, 13.8% in Toulouse reported taking lipid-lowering drugs vs. 1.6% in Belfast. As predicted, a history of myocardial infarction (MI) was highest in Belfast (6.1%) and lowest in Toulouse (1.2%). Some 7.1% of Belfast men reported a medical diagnosis of angina vs. 1.5% in Toulouse. Subjects showing evidence of pre-existing IHD will be studied prospectively but treated in the analysis as an additional variable. These results provide a measure of reassurance that these cohorts are representative of the communities from which they are drawn and provide a reliable baseline for prospective evaluation and cross-sectional comparisons. The levels of the classical risk factors found in this study, particularly when examined in combination, as multiple logistic functions based on previous British studies, are very similar between centres and cannot explain the large differences in the incidence of IHD which exist. Additional risk factors may help explain, at least in part, the major differences in incidence of IHD between these study centres. (+info)
Incidence of rectosigmoid adenomatous polyps in subjects without prior colorectal adenoma or cancer: a prospective cohort study.
BACKGROUND: Subjects without known colorectal adenomas or cancer constitute a large majority of the population where 85% of all cases of colorectal cancer are thought to occur. Consequently these people should be considered for screening to decrease mortality from colorectal cancer in the general population. AIMS: To estimate the incidence rate of rectosigmoid adenomas in these subjects. METHODS: Subjects without adenomas or cancer at a previous examination which had visualised the rectosigmoid underwent a fibre endoscopy every three years. Endoscopic data and population characteristics were collected prospectively. RESULTS: A total of 450 subjects fulfilled the selection criteria; 287 (64%) underwent at least two examinations, and 163 had three or more. At the second examination, with a mean delay of 39 months, the incidence rate of rectosigmoid adenomas was 1.50% per patient year. The rate was 1.75% per patient year (95% CI 0.80-3.33) at the third endoscopy with an additional mean delay of 38 months. The cumulative incidence rate at six years was 7.3% (95% CI 4.3-10.3), representing a mean of 1.2% per patient year. This rate increased with age and was higher for men than for women after age adjustment (p< 0.03). CONCLUSIONS: The incidence rates are very low compared with those of patients with prior adenomas. These results should be considered in establishing rectosigmoid adenoma screening strategies. (+info)
Evidence of improving survival of patients with rectal cancer in france: a population based study.
BACKGROUND: Over the past 20 years there have been many changes in the management of rectal cancer. Their impact on the overall population is not well known. AIMS: To determine trends in management and prognosis of rectal cancer in two French regions. SUBJECTS: 1978 patients with a rectal carcinoma diagnosed between 1978 and 1993. METHODS: Time trends in treatment, stage at diagnosis, operative mortality, and survival were studied on a four year basis. A non-conditional logistic regression was performed to obtain an odds ratio for each period adjusted for the other variables. To estimate the independent effect of the period a multivariate relative survival analysis was performed. RESULTS: Over the 16 year period resection rates increased from 66.0% to 80.1%; the increase was particularly noticeable for sphincter saving procedures (+30.6% per four years, p=0.03). The percentage of patients receiving adjuvant radiotherapy increased from 24.0% to 40.0% (p=0.02). The proportion of patients with Dukes' type A cancer increased from 17. 7% to 30.6% with a corresponding decrease in those with more advanced disease. Operative mortality decreased by 31.1% per four years (p=0.03). All these improvements have resulted in a dramatic increase in relative survival (from 35.4% for the 1978-1981 period to 57.0% for the 1985-1989 period). CONCLUSIONS: Substantial advances in the management of rectal cancer have been achieved, but there is evidence that further improvements can be made in order to increase survival. (+info)
Faecal occult blood screening and reduction of colorectal cancer mortality: a case-control study.
To estimate the efficacy of screening on colorectal cancer mortality, a population-based case-control study was conducted in well-defined areas of Burgundy (France). Screening by faecal occult blood test prior to diagnosis in cases born between 1914 and 1943 and who died of colorectal cancer diagnosed in 1988-94 was compared with screening in controls matched with the case for age, sex and place of residence. Cases were less likely to have been screened than controls, with an odds ratio (OR) of 0.67 [95% confidence interval (CI) 0.48-0.94]. The negative overall association did not differ by gender or by anatomical location. The odds ratio of death from colorectal cancer was 0.64 (95% CI 0.46-0.91) for those screened within 3 years of case diagnosis compared with those not screened. It was 1.14 (95% CI 0.50-2.63) for those screened more than 3 years before case diagnosis. There was a negative association between the risk of death from colorectal cancer and the number of participations in the screening campaigns. The inverse association between screening for faecal occult blood and fatal colorectal cancer suggests that screening can reduce colorectal cancer mortality. This report further supports recommendations for population-based mass screening with faecal occult blood test. (+info)
Risk factors for the occurrence of sporadic Salmonella enterica serotype enteritidis infections in children in France: a national case-control study.
To determine risk factors associated with the occurrence of sporadic cases of Salmonella enteritidis infections among children in France, we conducted a matched case-control study. Cases were identified between 1 March and 30 September 1995. One hundred and five pairs of cases and controls matched for age and place of residence were interviewed. In the 1-5 years age group, illness was associated with the consumption of raw eggs or undercooked egg-containing foods (OR 2.4, 95% CI 1.2-4.8). Storing eggs more than 2 weeks after purchase was associated with Salmonella enteritidis infection (OR 3.8, 95% CI 1.4-10.2), particularly during the summer period (OR 6.0, 95% CI 1.3-26.8). Cases were more likely to report a case of diarrhoea in the household 10-3 days before the onset of symptoms, particularly in the age group < or = 1 year (P = 0.01). This study confirms the link between eggs and the occurrence of sporadic cases of Salmonella enteritidis among children, highlights the potential role of prolonged egg storage and underlines the role of person-to-person transmission in infants. (+info)