Search PubMed⌕ Search

Biomedical subjects

C Belanger

Publications and source records attributed to C Belanger.

51 records · Page 3Linked to original sources
PubMed1981

Early age at first birth and decreased risk of breast cancer.

The relationship between age at birth of a first child and breast cancer was evaluated for 1159 affected women and 11,590 women without cancer in data collected in 1976 among married female registered nurses residing in 11 states in the United States. A positive trend of increasing risk of breast cancer with later ages at first birth was found (chi 2(1) for trend in proportions = 30.9, p less than 0.01). Adjustment for potential confounding variables by multiple logistic regression did not affect this trend. The presence of this relationship using non-hospitalized controls of similar social status to cases supports the reality of this association, which has recently been challenged as an artifact due to inappropriate choice of hospitalized controls.

Adult↗
PubMed1981

Use of postmenopausal hormones and risk of myocardial infarction.

Information was collected by mail survey about myocardial infarction (MI), use of female hormones after menopause, and coronary risk factors 121,964 registered nurses ages 30-55 years. One hundred twenty-three women with a known type of prior menopause reported hospitalization for MI. Overall, use of female hormones by these women was very similar to that of control women matched for age and type of menopause. Compared with nonusers, the relative risk (RR) for women who had ever taken female hormones was 0.9 (95% confidence limits 0.6-1.2), and for current users the RR was 0.7 (0.5-1.1). For women with bilateral oophorectomy, the RR for current users was 0.4 (0.2-0.8). These data imply that, at present, a decision to prescribe postmenopausal hormones should be based primarily on weighing possible benefits from the relief of menopausal symptoms against unknown or suspected risks of other diseases, particularly uterine cancer in women with an intact uterus.

Adult↗
PubMed1980

Oral contraceptive use in relation to nonfatal myocardial infarction.

The relation of oral contraceptive (OC) use to the risk of hospitalization for myocardial infarction (MI) was evaluated among 121,964 US nurses who responded to a mail questionnaire. There were 156 women who reported having been hospitalized for MI before the menopause, and 23 (15%) were OC users at the time of the MI. Of 3120 controls matched to the cases for menopausal status at the time of the MI and for age, 304 (10%) were using OCs at the time of the MI. The apparent increase in the risk of MI for current OC users was not explained by cigarette smoking, hypertension, elevated cholesterol or other identified risk factors for MI. We estimated that OC use increased MI risk 1.8-fold overall and 2.8-fold among nonsmokers without other risk factors. The increase in risk attributable to the combined effect of current OC use, cigarette smoking and hypertension was considerably greater than what would be predicted from the sum of the separate effects of these factors.

Contraceptives, Oral↗
PubMed1980

Family history of breast cancer as a risk indicator for the disease.

Family history of breast cancer was examined among 1159 women who themselves had breast cancer and among 11,590 control subjects in a retrospective case-control study conducted in 1976 among a sample of female nurses in the United States. Having a mother with breast cancer increased a woman's risk of developing the disease by 80%, while having a sister with such a history increased the risk by 150%. Adjustment for potential confounding variables by logistic regression analysis did not alter these estimates appreciably. Both these associations were stronger at younger ages of onset of cancer, and in a positive maternal history was correlated with a larger increase in risk in women who menstruated for more than 35 years.

Adult↗
PubMed1980

Characteristics of respondents and non-respondents to a mailed questionnaire.

In establishing a cohort of U.S. nurses, an assessment of response bias was made comparing respondents and non-respondents with regard to age, education, state of residence, employment status, field of employment, and major specialty. Overall, the 122,328 respondents (69.7 per cent) and 43,222 non-respondents were quite similar. Together with the reasonable response rate in a homogeneous population, this suggests that estimation of exposure-disease associations is unlikely to be affected by major bias due to non-response.

Adult↗
PubMed1971

Studies of the secretion of monkey placental lactogen.

A radioimmunoassay for monkey placental lactogen (MPL) was developed to study the factors controlling the secretion of MPL. The sensitivity of the assay was 1 ng MPL per ml. Human and monkey growth hormone, and human placental lactogen (HPL) showed minimal cross-reactions with MPL. Maternal MPL concentrations as measured in 40 rhesus monkeys increased progressively throughout pregnancy to a mean of 5000 ng/ml at term while umbilical vein MPL was less than 50 ng/ml. After term delivery maternal MPL concentrations decreased rapidly with a t(1/2) of 20 min.After fetectomy but with retention of the placenta, MPL concentrations decreased by 25% reaching a plateau over a 6 hr period. Experimental abruption of the secondary placenta within 1 hr produced a 50% decrease in MPL concentration. After ligation of the fetal vessels supplying the secondary placental disc, MPL increased transiently and then decreased to levels significantly below those of the control period. These studies suggest MPL secretion is not directly controlled by the fetus but is sensitive to changes in placental blood flow. The pregnant rhesus monkey serves as a useful model for investigating factors which may regulate HPL secretion because of the close similarity between MPL and HPL secretion.

Animals↗
PubMedDate not supplied

Multicentre combined chemotherapy protocol for large cell advanced non Hodgkin's lymphoma.

Between October 1985 and October 1989, 75 previously untreated patients with stage III and IV non Hodgkin's lymphoma, large cell type, were treated with an alternating weekly chemotherapy regimen including the following drugs: week 1: Doxorubicin, vincristine, cyclophosphamide, bleomycin, and intrathecal (i.th.) methotrexate and cytarabine; week 2: Methotrexate with leucovorin rescue; week 3: Doxorubicin, ifosfamide with mesna, etoposide, and i.th. methotrexate and cytarabine; week 4: Methotrexate with leucovorin rescue. Complete responders after three cycles according to this schedule (12 weeks) were given 18 gys cranial irradiation and randomized between one additional cycle or three monthly CHOP (consolidation treatment). Among 66 evaluable patients, 53 achieved a complete remission (CR 80 per cent) and seven a partial remission (11 per cent). There were six failures, and nine early deaths during the initial phase, mostly due to septic problems. Forty-one of the 53 CR patients (77.3 per cent) have remained free of disease with a median follow-up of 15 months (1-49). Eight of the 12 relapses occurred during the first year, the four others at 13, 14, 16 and 38 months respectively. The 2-year survival was 63 per cent for the whole group, and 77 per cent for the CR group. No difference has been observed up until now between the two groups with different consolidation treatment. Therefore, this protocol seems to be able to produce a high rate of complete and durable remission. The analysis of prognostic factors suggests that some high-risk patients should be considered for intensification therapy with the support of autologous bone marrow transplantation.

Adolescent↗
PubMedDate not supplied

The dose of granulocyte-colony-stimulating factor after chemopriming treatment does not influence apheresis yield of progenitor cells: a retrospective study of 91 cases.

BACKGROUND: The optimal dose of post-chemotherapy granulocyte-colony-stimulating factor (G-CSF) administration before peripheral blood progenitor cell (PBPC) collection has not been determined as yet, although 5 microg per kg per day has been recommended as the standard dose. This study retrospectively analyzed the effect of G-CSF dose on peripheral blood CD34+ cell collection from 91 patients with hematologic malignancies. STUDY DESIGN AND METHODS: Various doses of G-CSF were administered after several chemotherapeutic PBPC mobilization regimens. According to the dose of G-CSF administered, patients were assigned to two groups. Group 1 included 46 patients who received a low dose of G-CSF (median, 3.6 [range, 2.8-4.6] microg/kg/day). Group 2 included 45 patients who received a standard G-CSF dose of 6.0 (5.5-8. 1) microg per kg per day. Patients in the two groups were matched for age, diagnosis, previous therapy, and chemotherapeutic PBPC mobilization regimens. RESULTS: No difference was observed in the median number of CD34+ cells harvested from each group. The number of leukapheresis procedures necessary to obtain a minimum of 3 x 10(6) CD34+ cells per kg was the same in both groups, and the percentage of patients who failed to achieve adequate PBPC collections was similar in the two groups. CONCLUSION: The administration of low-dose G-CSF after chemotherapy appears equivalent to administration of the standard dose in achieving satisfactory PBPC collection. This approach could allow significant savings in medical cost. A randomized and prospective study is necessary, however, to assess the validity of these conclusions.

Adult↗