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Biomedical subjects

R Massé

Publications and source records attributed to R Massé.

At least 19 recordsLinked to original sources
PubMed2004

[Breast cancer: dangers of alleged certainties].

The artificial increase of breast cancer incidence is estimated as amounting to 30,000 new cases in the year 2000 in France. This increase would be attributable to a 1.2% lack of specificity for the whole range of diagnostic procedures. Sociologically, it appears that the Hippocratic devise "primum nil nocere" ("first don't harm") has been replaced today by "primum agere" ("act first"). Professionals should give information about both limitations and risks of screening. From an ethical point of view, screening programs justify themselves arguing that "there can't be harm in doing good". Absence of alternative strategies is not a sufficient argument for justifying screening with its uncertain consequences.

Breast Neoplasms↗
PubMed2003

[Breast cancer detection and medicalization of public health].

The aim of reducing breast cancer mortality announced in the report on health in France published in 1994 strongly implicated the promotion of screening and early surgical treatment. However, this mortality has not evolved significantly in France, although more and more cancers have been found and operated upon. The increased prevalence rates of histological diagnoses of breast cancer obtained from the studies of autopsies published has shown that the screening has discovered non-terminal, benign cancers. It has been estimated that 120 of the surgical operations conducted per day in France in 1999 have been carried out to remove non-terminal, benign cancers. Public health has an ethical responsibility to face in terms of the allocation of resources and must remain vigilant in order to avoid excessive screening and unnecessary interventions.

Breast Neoplasms↗
PubMed2001

A pharmacokinetic study of amoxycillin in febrile beagle dogs following repeated administrations of endotoxin.

The pharmacokinetics of amoxycillin was studied in nine male beagle dogs under healthy and febrile conditions. In Period 1, dogs received 20 mg/kg of an oral suspension of amoxycillin. Intravenous doses of saline, 2 and 20 microg/kg of endotoxin (LPS from Escherichia coli serotype) were administered to dogs (three per group) prior to administration of 20 mg/kg of amoxycillin in Period 2. Rectal temperature and behavioral changes were recorded and blood samples were collected over 12 h for pharmacokinetic analysis. Amoxycillin was assessed in plasma using liquid chromatography coupled with mass spectrometry. Plasma concentrations were analysed using a one-compartment model with lag-time for absorption using an iterative two-stage method. As compared with control groups, amoxycillin clearance decreased significantly with preliminary treatments of 2 microg/kg endotoxin (0.209 vs. 0.140 L/h kg, P < 0.05) and 20 microg/kg endotoxin (0.214 vs. 0.075 L/h kg, P < 0.05). As a result of this, the area under curve for the 2 and 20 microg/kg endotoxin groups increased significantly 100.4 vs. 149.4 microg h/mL (P < 0.05) and 99.2 vs. 277.7 microg h/mL (P < 0.05), respectively. Other drugs currently used for the treatment of fever and septic shock should be re-evaluated using a febrile animal model to avoid improper dose administration.

Administration, Oral↗
PubMed2001

Most ten-year-old children with negative or unknown histories of chickenpox are immune.

To evaluate the proportion of children to vaccinate against varicella in a catch-up program targeting 9- to 10-year-old children, a study was conducted among children age 10 years to assess the age-specific incidence of varicella and document the immunity against varicella in those with negative or unknown chickenpox history. Of the latter 62% were seropositive for varicella.

Age Factors↗
PubMed2001

Importance of attributable risk in monitoring adverse events after immunization: hepatitis B vaccination in children.

OBJECTIVES: Most vaccine safety data present only the postvaccination incidence of all adverse events rather than an estimate of attributable risk. This study sought to illustrate the difference between the 2 estimates with data from a hepatitis B immunization program. METHODS: The incidence of health problems occurring before and after each dose of hepatitis B vaccine in a cohort of 1130 children were compared. RESULTS: Although 47.5% of all children reported an adverse event during the 4 weeks following each of the 3 doses, adverse events attributable to immunization occurred in only 10.6% of children. CONCLUSIONS: Postimmunization incidence systematically overestimates the risk of adverse events. Estimating actual attributable risk is necessary to avoid false beliefs regarding immunization.

Adverse Drug Reaction Reporting Systems↗
PubMed2000

Comparative immunogenicity under field conditions of two recombinant hepatitis B vaccines in 8-10-year-old children.

The immunogenicity of two hepatitis B vaccines was compared in 8-10-year-old children immunized in a school program. One year apart, 1129 children received Engerix-B 10 microg vaccine (EB), and 1126 received Recombivax-HB 2.5 microg (RB), following the 0, 1, 6 schedule. Blood samples were collected one month after the third dose. Anti-Hbs were measured by commercial radioimmunoassay. In the EB group, 99.1% of the children seroconverted (>/=2 IU/l) compared to 99.7% in the RHB group (p=0.09). The seroprotection rate (>/=10 IU/l) was similar for both groups: 98.9% in the EB group and 99.2% in the RB group (p=0.66). However, GMCs of anti-HBs were higher in children given EB compared to those given RB (7307 vs. 3800 mIU/ml, p<0.0001). This study showed that both vaccines were highly immunogenic, in the course of a regular field immunization program. However, the difference observed in the antibody levels attained according to the vaccine may play a role in the long-term protection of these children.

Child↗
PubMed2000

Qualitative and quantitative analyses of psychological distress: methodological complementarity and ontological incommensurability.

Rigorous qualitative and quantitative methodologies have been used for the development of a multidimensional scale dedicated to the measurement of psychological distress. A comparison between the idioms of distress or the cultural forms through which French Quebecois express their distress (qualitative constructs) and the nonorthogonal factors derived from explanatory and higher order factorial analyses (quantitative constructs) illustrates the possibilities of complementarity between qualitative and quantitative approaches. The comparison shows that these two operationalizations of the concept of psychological distress are founded on incommensurable representations of distress. This article concludes that this representational dilemma of distress as a lived language or as an empirical reified entity leads to an ontological and a teleological incommensurability.

Ethnicity↗
PubMed1996

Proposed definitive methods for measurement of plasma testosterone and 17 alpha-hydroxyprogesterone.

OBJECTIVES: This report provides the results of the development and evaluation of definitive isotope dilution/mass spectrometry (ID/MS) methods for the determination of testosterone and 17 alpha-hydroxyprogesterone in human plasma at concentrations ranging from 1.4 to 37.9 nmol/L and 1.5 to 45.4 nmol/L, respectively. The internal standards were 16, 16, 17-2H-testosterone and 21,21,21, -2H-17 alpha-hydroxyprogesterone. The development of optimum extraction and derivatization procedures, and studies of storage time, temperature effects, accuracy, and precision are presented. RESULTS: The results indicate that the methods employing the TBDMS derivative of testosterone and MO-TMS derivative of 17 alpha-hydroxyprogesterone are capable of generating accurate and precise data at the inherently low concentrations given, with recovery greater than 95%. Accuracy of testosterone in the fortified steroid-free and pooled plasma by ID/MS measurement was good because the relative error ranged from +3.1% to -0.7, with a mean of 0.9% over the concentration levels of 1.4 to 37.9 nmol/L testosterone, and the imprecision ranged from 4.2% to 0.7% CV, with a mean of 1.9%. Accuracy of 17 alpha-hydroxyprogesterone in the fortified steroid-free and pooled plasma was also good, considering the inherently low concentrations. The relative error ranged from -2.1% to +1.5%, with a mean of 1.1%, and the imprecision ranged from 3.8% to 0.8% CV with a mean of 1.3% over concentration levels of 1.5 to 15.1 nmol/L. The high precision and accuracy and absence of statistically significant bias qualifies these methods as candidate definitive methods for plasma testosterone and 17 alpha-hydroxyprogesterone.

17-alpha-Hydroxyprogesterone↗
PubMed1996

Effectiveness of a whole cell pertussis vaccine in child-care centers and schools.

BACKGROUND: Pertussis has substantially increased in Quebec, Canada, since 1990. We estimated pertussis vaccine effectiveness and vaccine coverage in child-care centers and elementary schools. METHODS: Two retrospective cohort studies were simultaneously conducted. One included 4482 children attending 88 public child-care centers and the other included 3429 pupils in 14 elementary schools. Cough and pertussis symptoms were assessed through a questionnaire and medical records; immunization status was ascertained by examination of written records. RESULTS: In child-care centers 95% of children had received at least three vaccine doses at the beginning of the follow-up; in schools more than 98% of pupils had received at least 4 doses. With > or = 4 doses of vaccine and a standard case definition used for surveillance (cough > or = 2 weeks, > or = 1 pertussis symptom and no other apparent cause for cough), vaccine effectiveness was estimated at 61% (95% confidence interval, 44 to 72%) in child-care centers and at 60% (95% confidence interval, 10 to 82%) in schools. With the same number of doses but a case definition requiring a cough > or = 5 weeks, vaccine effectiveness increased to 71% (95% confidence interval, 49 to 83) in child-care centers and to 86% (95% confidence interval, 66 to 94%) in schools. CONCLUSIONS: The increase in pertussis in Quebec is not caused by a low vaccine coverage. A low vaccine effectiveness may contribute to the resurgence of pertussis in the past decade.

Canada↗
PubMed1995

[Markers of depression regarding DSM and popular diagnosis: an analysis of concordance in Quebec patients].

OBJECTIVE: To query the universality of affective disorder markers, particularly the level of consistency between DSM diagnostic criteria and the criteria implicit in popular diagnoses. METHOD: Utilization of data from the Santé Québec (1987) survey to compare depression markers reported by respondents who identified themselves or were identified by a member of their household as "suffering from depression" and markers underlying DSM-III diagnostic criteria. RESULTS: A popular diagnosis of depression is implicitly different from a psychiatric diagnosis considering an interdiagnosis similarity of 9.5%. CONCLUSION: It is therefore important to become more knowledgeable about the markers underlying diagnosis of affective disorders.

Adolescent↗
PubMed1994

[From deinstitutionalization to social rejection: the point of view of ex-psychiatric patients].

A series of in-depth interviews conducted with ex-psychiatric patients who use alternative resources in the area of mental health has revealed several manifestations of rejection, stigmatization and discrimination. These are experienced as significant and determining with respect to the social integration of patients, as well as harmful to their quality of life in the community. Data shows that this population suffers from social isolation due to lack of communication with community members and from various forms of rejection and disparating attitudes on the part of entourage. Their fragile socio-economic conditions confine them to live in a sub-culture and at the fringe of society.

Adult↗
PubMed1992

Studies on anabolic steroids. 9. Tertiary sulfates of anabolic 17 alpha-methyl steroids: synthesis and rearrangement.

A simple and convenient method has been developed to prepare sulfates of anabolic 17 beta-hydroxy-17 alpha-methyl steroids. The sulfates of methandienone, 17 alpha-methyltestosterone, mestanolone, oxandrolone, and stanozolol were prepared. Different A-ring functions were not affected under the sulfation condition. The buffered hydrolyses of these sulfates provided the 17-epimers of the original steroids and 17,17-dimethyl-18-nor-13(14)-ene steroids, presumably via the 17-carbocations.

Anabolic Agents↗
PubMed1992

Studies on anabolic steroids. 10. Synthesis and identification of acidic urinary metabolites of oxymetholone in a human.

Two major unconjugated acidic metabolites of oxymetholone (17 beta-hydroxy-2-hydroxymethylene-17 alpha-methyl-5 alpha-androstan-3-one, 1), namely, 17 beta-hydroxy-17 alpha-methyl-2,3-seco-5 alpha-androstane-2,3-dioic acid (2) and 3 alpha,17 beta-dihydroxy-17 alpha-methyl-5 alpha-androstane-2 beta-carboxylic acid (6a), were detected by gas chromatography/mass spectrometry in urine samples collected after oral administration of 1 to a human volunteer. Reference steroid 2 was synthesized and identified. The identification of urinary metabolite 6a was based on the synthesis of its stereoisomers and the isomerization of the methyl ester 6b to its 2-epimer, 3 alpha,17 beta-dihydroxy-17 alpha-methyl-5 alpha-androstane-2 alpha-carboxylic acid methyl ester (9b). The mechanisms accounting for the formation of these acidic metabolites are discussed.

Acids↗
PubMed1992

Studies on anabolic steroids--8. GC/MS characterization of unusual seco acidic metabolites of oxymetholone in human urine.

One of the biotransformation routes of oxymetholone (17 beta-hydroxy-2-hydroxymethylene-17 alpha-methyl-5 alpha-androstan-3-one) in man leads to the formation of 17 beta-hydroxy-17 alpha-methyl-5 alpha-androstan-3-one (mestanolone). To demonstrate that this latter steroid may be formed by decarboxylation of an intermediate metabolite of oxymetholone bearing a 2-carboxylic group, we studied the urinary excretion of oxymetholone acidic metabolites. Five new acidic metabolites are reported here for the first time, among which four are unusual seco steroids resulting from the oxidative cleavage of the A-ring. The most abundant compound is 17 beta-hydroxy-17 alpha-methyl-2,3-seco-5 alpha-androstane-2,3-dioic acid 1, the cumulative excretion of which accounted for 1.52% of the dose. Three other seco diacids were produced in smaller amounts, namely 17 beta-hydroxy-17 alpha-methyl-2,3-seco-5 alpha-androstane-2,4- dicarboxylic acid 3, 17 beta-hydroxy-17 alpha-methyl-1,3-seco-5 alpha-androstane-1,3-dioic acid 4 and 17 beta-hydroxy-17 alpha-methyl-2,4-seco-5 alpha-androstane-2,4-dioic acid 5. The fifth acidic metabolite was identified as 3 alpha, 17 beta-dihydroxy-17 alpha-methyl-5 alpha-androstane-2 beta-carboxylic acid 2. The excretion in urine of these acidic metabolites suggests that the 2-hydroxymethylene group in oxymetholone is readily oxidized to yield the corresponding beta-keto acid which can be (1) decarboxylated to form mestanolone; (2) reduced at C-3 to give compound 2; and (3) further oxidized to afford the unexpected seco diacids 1, 3, 4 and 5. The identity of compounds 1 and 2 was ascertained by GC/MS and 1H and 13C-NMR analysis of reference compounds. The other metabolites were characterized by GC/MS analysis.

Adult↗
PubMed1992

Studies on anabolic steroids--12. Epimerization and degradation of anabolic 17 beta-sulfate-17 alpha-methyl steroids in human: qualitative and quantitative GC/MS analysis.

The epimerization and dehydration reactions of the 17 beta-hydroxy group of anabolic 17 beta-hydroxy-17 alpha-methyl steroids have been investigated using the pyridinium salts of 17 beta-sulfate derivatives of methandienone 1, methyltestosterone 4, oxandrolone 7, mestanolone 10 and stanozolol 11 as model compounds. Rearrangement of the sulfate conjugates in buffered urine (pH 5.2) afforded the corresponding 17-epimers and 18-nor-17,17-dimethyl-13(14)-enes in a ratio of 0.8:1. These data indicated that both epimerization and dehydration of the 17 beta-sulfate derivatives were not dependent upon the respective chemical features of the steroids studied, but were instead inherent to the chemistry of the tertiary 17 beta-hydroxy group of these steroids. Interestingly, in vivo studies carried out with human male volunteers showed that only methandienone 1, methyltestosterone 4 and oxandrolone 7 yielded the corresponding 17-epimers 2, 5 and 8 and the 18-nor-17,17-dimethyl-13(14)-enes 3, 6 and 9 in ratios of 0.5:1, 2:1 and 2.7:1, respectively. No trace of the corresponding 17-epimers and 18-nor-17,17-dimethyl-13(14)-enes derivatives of mestanolone 10 and stanozolol 11 was detected in urine samples collected after administration of these steroids. These data suggested that the in vivo formation of the 17-epimers and 18-nor-17,17-dimethyl-13(14)-enes derivatives of 17 beta-hydroxy-17 alpha-methyl steroids is also dependent upon phase I and phase II metabolic reactions other than sulfation of the tertiary 17 beta-hydroxyl group, which are probably modulated by the respective chemical features of the steroidal substrates. The data reported in this study demonstrate that the 17-epimers and 18-nor-17,17-dimethyl-13(14)-enes are not artifacts resulting from the acidic or microbial degradation of the parent steroids in the gut as previously suggested by other authors, but arise from the rearrangement of their 17 beta-sulfate derivatives. Unchanged oxandrolone 7 was solely detected in the unconjugated steroid fraction whereas unchanged steroids 1, 4 and 11 were recovered from the glucuronide fraction. These data are indirect evidences suggesting that the glucuronide conjugates of compounds 1 and 4 are probably enol glucuronides and that of compound 11 is excreted in urine as a N-glucuronide involving its pyrazole moiety. The urinary excretion profiles of the epimeric and 18-nor-17,17-dimethyl-13(14)-ene steroids are presented and discussed on the basis of their structural features.

Adult↗
PubMed1991

Chlamydia trachomatis cervical infection: prevalence and determinants among women presenting for routine gynecologic examination.

OBJECTIVE: To determine the prevalence of and risk indicators for Chlamydia trachomatis cervical infection among women presenting for a periodic medical examination. DESIGN: Prevalence study. SETTING: Centre local de services communautaires (CLSC) Saint-Louis du Parc, Montreal. PATIENTS: All women presenting for a routine gynecologic examination from May 1985 to July 1986. Of the 773 (99%) who agreed to participate 56 were excluded because of inadequate diagnostic tests (34), antibiotic intake in the preceding 6 weeks (19) or loss to follow-up after the initial visit (3). OUTCOME MEASURES: Culture was the diagnostic standard, but rapid diagnostic tests were also used. From the identified cases logistic regression analysis was used to evaluate the following risk indicators: age, place of residence, use of oral contraceptives, sexual partners and frequency, history of sexually transmitted disease (STD) and abnormalities found on genital examination. MAIN RESULTS: Fifty-one of the women were found to have C. trachomatis infection, for a prevalence rate of 7.1%; 32 (63%) were completely asymptomatic. Three independent indicators were found: age of 25 years or less (odds ratio [OR] 3.2, 95% confidence limits [CL] 1.8 and 5.9), cervical erythema, contact bleeding or mucopurulent exudate (OR 2.5, 95% CL 1.4 and 4.5) and residency in the CLSC area (OR 2.3, 95% CL 1.1 and 5.1). A history of STD or vaginitis had a significant protective effect in women 30 years of age or more (OR 0.2). CONCLUSIONS: Case-finding for chlamydial infection could be an effective public health measure among women 25 years of age or less and among those with signs of cervicitis when they present for a Papanicolaou test.

Adolescent↗
PubMed1991

Microbial dehalogenation of 4,4'-dichlorobiphenyl under anaerobic conditions.

Anaerobic cultures containing 4,4'-dichlorobiphenyl (4,4'CB) were inoculated with various environmental samples. The degradation of the substrate was followed by gas chromatographic analysis. Three of the cultures tested showed an ability to dehalogenate the substrate, as judged by the presence of 4-chlorobiphenyl and biphenyl in those media inoculated with them.

Anaerobiosis↗