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J Rochon

Publications and source records attributed to J Rochon.

50 records · Page 3Linked to original sources
PubMed1986

Distal tubule bicarbonate accumulation in vivo. Effect of flow and transtubular bicarbonate gradients.

We have performed microperfusion studies on distal tubules of normal and alkalotic rats in an attempt to demonstrate in vivo bicarbonate secretion. All perfusion solutions were free of phosphate and other nonbicarbonate buffers. In both normal and alkalotic rats, distal perfusions elicited significant tCO2 entry only at high flow (24 nl/min). Even when perfusate tCO2 concentration closely matched plasma tCO2 concentration (30 mM tCO2), significant tCO2 entry again occurred at high flow. This was associated with a rise of the perfusate tCO2 concentration, which indicated net entry of tCO2 against a concentration gradient. In this "symmetrical" perfusion situation, acetazolamide blockade prevented tCO2 entry. Accordingly: distal tubule tCO2 entry is demonstrable in both alkalotic and normal rats at high flow rates; increasing perfusate tCO2 concentration can suppress tCO2 entry; and entry can occur in the absence of a gradient and this effect can be blocked by acetazolamide.

Acetazolamide↗
PubMed1986

[Absenteeism as a predictor of severe morbidity. A double case-control study (myocardial infarction and industrial accident) in a large company of the Quebec Province].

Are absenteeism indicators usefull as predictor of serious morbidity in a working population? To seek an answer was the objective of a double case-control study carried out in a large company (17000 workers) of Quebec Province. In the first study, 64 cases of myocardial infarction (incidence density = 1.66% +/- 0.35) were compared with 64 controls matched for sex, age and type of work. In the second one, 142 cases of labor accident were compared with 142 controls sampled in a similar way. Absenteeism frequency and length were analysed during the period of 6 to 12 years prior to the onset of the health problem. Ratios were calculated on an individual basis for all causes of absence and for sick leave; they were adjusted for length of service. A four classes interval scale was used for the comparison. An excess of absence length exists in the two studies. The excess is not significant for the myocardial infarction cases (+ 33%, with a statistical power = 51%). It is significant for the labor accident cases (+ 52%, p less than 0.01). The corresponding odds ratio calculated in reference to the lowest absence group were 2.4 (0.9-6.6) and 2.7 (1.5-4.9). The cumulative absence length can be considered as a predictor of serious disease. A conceptual framework of the relationship between absence and natural disease history is presented. The epidemiological approach to the phenomenon of absence is certainly usefull in spite of the controversy underlined by the social sciences.

Absenteeism↗
PubMed1985

Lipid profile of a French-Canadian population: 1. Association of plasma lipid and lipoprotein levels with age, relative body weight and education.

Plasma lipid and lipoprotein levels were determined in a randomly selected population of 1169 French-Canadian men in the Quebec City area. The mean levels of total plasma cholesterol and triglycerides were 224.0 and 166.5 mg/dL respectively. The mean level of low-density lipoprotein cholesterol was higher and the mean level of high-density lipoprotein (HDL) cholesterol lower than those reported in a recent study in English-Canadian men. The mean HDL2 and HDL3 levels were lower than those reported in American men. Stratification of plasma triglyceride levels for all age groups showed that mean HDL2 levels decreased rapidly with moderate rises in triglyceride levels. Less than 9% of the variation in lipid or lipoprotein levels was related to age or relative body weight. Education had no significant effect on the levels.

Adult↗
PubMed1985

Correlation of stress with outcome of radioiodine therapy for Graves' disease.

Between November 1965 and December 1983, 293 patients were treated for Graves' disease using 131I. All patients were asked to identify a stressful event antedating the onset of overt clinical symptoms. Eighty-one patients were able to do this (27.6%). Six patients were lost to follow-up, the others were followed from 1 to 155 mo. Two hundred forty-four patients received a single treatment, 49 required two or more treatments. Stress and nonstress individuals were consistent with respect to age, sex, number of treatments and the dose of radioiodine. Patients with stress initiating the symptoms of Graves' disease became hypothyroid earlier, 50% at 12 mo compared with 36 mo for the nonstress group, p = 0.01. At 10 yr 5% of the stress group remained euthyroid compared with 17% nonstress. We conclude that stress in the 12 mo or less before the onset of clinical symptoms potentiates the development of hypothyroidism induced by a standard dose of radioiodine.

Adolescent↗
PubMed1983

[Incidence of arterial hypertension in the Quebec region].

The objectives of this study were to determine the incidence of high blood pressure (HBP) in Quebec suburbs and evaluate age, baseline blood pressure level and overweight as determinants of future hypertension. From a cohort of 4828 men, aged 35-64, screened in 1974, 1090 normotensives (blood pressure less than 160/95 mmHg without medication) free of cardiovascular disease were re-evaluated in 1979-1980. Among these 1090 men, 183 have developed a blood pressure greater than or equal to 160/95 mmHg or less than 160/95 mmHg associated with antihypertensive medication. There was no significant variation of the incidence by age (10-year strata). In the group of subjects with a baseline systolic blood pressure (SBP) between 140 and 159 mmHg the incidence of systolic hypertension was 6.3 times higher than in the group with baseline SBP less than 140 mmHg. Similarly, in the group of subjects with a baseline diastolic blood pressure (DBP) between 90 and 94 mmHg the incidence of diastolic hypertension was 3 times higher than in the group with a baseline DBP less than 90 mmHg. The incidence of HBP was correlated with overweight. Furthermore overweight was a highly prevalent risk factor in the study population. In summary, the incidence of HBP is 169 per 1000 in 5 years. Baseline blood pressure and overweight are strong determinants of a future HBP and can be used to identify the high risk subgroup.

Adult↗
PubMedDate not supplied

Pattern of care and impact of participation in clinical studies on the outcome in ovarian cancer.

The purpose of this study was to evaluate the pattern and quality of care for ovarian cancer in Germany and analyze prognostic factors with emphasis on characteristics of treating institutions, hospital volume, and participation in clinical trials. This study utilized national survey including patients with histologically proven invasive epithelial ovarian cancer diagnosed in the third quarter of 2001 including descriptive analysis of pattern of surgical care and systemic treatment in early (FIGO I-IIA) and advanced (FIGO IIB-IV) ovarian cancer and both univariate and multivariate analysis of prognostic factors. One third of all patients diagnosed in the third quarter of 2001 in Germany, 476 patients, were included. Standard care according to German guidelines was provided to only 35.5% of patients with early ovarian cancer. Recommended chemotherapy was given to 78% in advanced disease. Multivariate analysis showed advanced stage, poor performance status, comorbidity, ascites, and treatment in an institution not participating in cooperative studies to be associated with inferior survival. Non-participation was associated with an 82% increase of risk (HR = 1.82; 95% CI, 1.27-2.61; P= 0.001). Hospital volume did not affect treatment outcome. Adherence to treatment guidelines showed remarkable variety among German hospitals, indicating options and need for improvement. Selecting an institution that participates in cooperative trials might be an option for individual patients seizing the chance for better quality of care even when individual factors might hamper enrollment in a study.

Aged↗
PubMedDate not supplied

A prospective randomized controlled trial of initial immunosuppression with ALG versus OKT3 in recipients of cardiac allografts.

Thirty-nine heart transplant recipients were randomized prospectively to receive OKT3 or antilymphoblast globulin (ALG) for 7 days, having otherwise identical protocols (group 1: OKT3, n = 20 patients; group 2: ALG, n = 19 patients). No preoperative immunosuppression was given. The protocol consisted of methylprednisolone, 500 mg intraoperatively, followed by 1 mg/kg/day, intravenously or orally, tapering to 0.2 mg/kg/day at 1 month; oral cyclosporine starting 3 to 5 days after transplantation; selective use of azathioprine, 1 to 4 mg/kg/day; and either OKT3, 5 mg/day for 7 days, or ALG, 15 mg/kg/day for 7 days. Of the 39 patients in the study, 34 are alive 6 months to 2 years after transplantation. The actuarial survival at 2 years for the OKT3 and ALG groups was 92% (+/- 0.07%) and 83% (+/- 0.09%), respectively (not significant [NS]). The time to first rejection for group 1 was 5.6 weeks and for group 2 was 5.3 weeks (NS). The mean number of rejections for group 1 and group 2 was 2.1 episodes per patient and 1.4 per patient, respectively (NS). Three patients in each group were free of rejection at 6 months. The total number of infections at 6 months was 1.05 per patient in group 1, 0.74 per patient in group 2 (NS), with 35% of patients receiving OKT3 and 52% of patients receiving ALG actuarially free of infection by 6 months after surgery (NS). During the first 24 hours after surgery, no significant differences were noted in mean blood pressure, central venous pressure, or Po2 between the groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Actuarial Analysis↗