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Michel Rossignol

Publications and source records attributed to Michel Rossignol.

45 records · Page 3Linked to original sources
PubMed2003

Is physical activity differentially associated with different types of sedentary pursuits?

OBJECTIVE: To determine whether there is a relationship between the time adolescents spend in physical activity and time they spend in different sedentary pursuits: watching television, playing video games, working on computers, doing homework, and reading, taking into account the effect of part-time work on students' residual time. DESIGN: Cross-sectional cohort design. PARTICIPANTS AND SETTING: Seven hundred forty-three high school students from 2 inner-city public schools and 1 private school. METHODS: Students completed a self-administered questionnaire that addressed time spent in physical activity, time spent in sedentary pursuits, musculoskeletal pain, and psychosocial issues and were also measured for height and weight. Main Outcome Measure Level of physical activity (low, moderate, high). RESULTS: There were more girls than boys in the low and moderate physical activity groups and more boys than girls in the high activity group. Ordinal logistic regression showed that increased time spent in "productive sedentary behavior" (reading or doing homework and working on computers) was associated with increased physical activity (odds ratio, 1.7; 95% confidence interval, 1.2-2.4), as was time spent working (odds ratio, 1.3; 95% confidence interval, 1.2-1.4). Time spent watching television and playing video games was not associated with decreased physical activity. CONCLUSIONS: Physical activity was not inversely associated with watching television or playing video games, but was positively associated with productive sedentary behavior and part-time work. Some students appear capable of managing their time better than others. Future studies should explore the ability of students to manage their time and also determine what characteristics are conducive to better time management.

Adolescent↗
PubMed2003

Proteomics of loosely bound cell wall proteins of Arabidopsis thaliana cell suspension cultures: a critical analysis.

The complete sequencing of the Arabidopsis thaliana genome allows the use of the recently developed mass spectrometry techniques to identify the cell wall proteins (CWPs). Most proteomic approaches depend on the quality of sample preparation. Extraction of CWPs is particularly complex since the proteins may be free in the apoplast or are embedded in a polysaccharide matrix where they are retained by Van der Waals interactions, hydrogen bonds, hydrophobic or ionic interactions, or cross-linked by covalent bonds. Specific and sequential extraction procedures thus need to be developed. We report on the sequential extraction of loosely bound CWPs from living A. thaliana cells in culture. Different salts and chelating agents were used for releasing the proteins from the wall. Their effects on the extraction of CWPs and on the integrity of the plasma membrane were evaluated. Bioinformatic software was used to identify proteins and to predict their sub-cellular localization. The obtained data show that the plasma membrane of cells in culture was easily damaged by some steps of the extraction procedure, leading to the release of increasing amounts of intracellular proteins. Nevertheless, we identified fifty CWPs among which thirteen were new proteins for the cell wall. In addition, 76% of these CWPs were basic proteins not resolved in two-dimensional (2-D) gel electrophoresis. The existence of two hypothetical proteins was confirmed. The structure of three proteins could be confirmed using mass spectrometry data.

Arabidopsis↗
PubMed2003

Unwanted infants: psychological and physical consequences of inadequate orphanage care 50 years later.

Studies of the effects in middle-aged adults of institutionalization at birth or early childhood are rare. The results of this study show that members of a randomly selected, middle-aged group of orphans, most of whom were institutionalized at birth, were significantly more psychosocially dysfunctional and had significantly more chronic illnesses that could be stress related than a randomly selected, matched community sample.

Adult↗
PubMed2002

Risk factors for the development of neck and upper limb pain in adolescents.

STUDY DESIGN: A prospective, repeated measures cohort study with high school students was conducted in Montreal, Canada. OBJECTIVE: To determine the incidence of neck and upper limb pain and associated risk factors in a cohort of adolescents. SUMMARY OF BACKGROUND DATA: Neck and upper limb pain is frequent in adolescents and may be associated with repetitive motion from certain activities such as playing music, working, and engaging in sports activities. METHODS: For this study, 502 students in the seventh to ninth grades in three schools were assessed. Data were collected at three times 6 months apart over a 12-month period. Students responded to a questionnaire addressing musculoskeletal health and lifestyle factors and were measured for height and weight. Neck or upper limb pain occurring at least once a week in the preceding 6 months was defined as the outcome. Multivariate methods were used to model the repeated measures dichotomous outcome as a function of engaging in physical activity, working, or playing a musical instrument, adjusted for covariates. RESULTS: The cumulative annual incidence of neck and upper limb pain was 28.4%. The risk factors for neck and upper limb pain were working (adjusted odds ratio, 1.89; 95% confidence interval, 1.11-3.32) and lower mental health score (adjusted odds ratio, 1.68; 95% confidence interval, 1.19-2). Students involved in childcare were at a higher risk for the development of pain (adjusted odds ratio, 2.25; 95% confidence interval, 1.18-4.29). CONCLUSIONS: Neck and upper limb pain is common in teenagers. Sports involvement and music participation were not risk factors for the development of neck and upper limb pain. However, pain was more likely to develop in adolescents who worked than in students who had a lower mental health score.

Adolescent↗
PubMed2002

Normal variation and influence of stress, caffeine intake, and sexual activity on uroflowmetry parameters of a middle-aged asymptomatic cohort of volunteer male urologists.

AIMS: To assess normal variations of uroflowmetry in middle-aged asymptomatic male urologists and to analyse the influence of stress, caffeine intake, and sexual activity. METHODS: Thirty-one male urologists from Quebec and Ontario were recruited for this study. All were healthy, not taking any current medications known to interfere with lower urinary tract function, and symptom-free (International Prostate Symptom Score less than 5). Each received two identical flowmeters to keep over a period of 2 weeks, one at home and one in his busiest office. Ten uroflow tracings, with a volume greater than 150 mL, were requested from each of them; five at home and five in the office. A total of 310 flows were analysed. The subjective level of stress, coffee intake, and sexual activity, in the hour before each uroflowmetrogram, was recorded, through a short self-administered questionnaire and stress visual scale. RESULTS: are presented as an average per individual. The voided volume was 331.9 mL, with an SD of 94.8 mL. The voiding time was 32.7 seconds (SD=15.5). The peak flow rate was 20.5 mL/sec (SD=3.9), the mean flow rate was 14.3 mL/sec (SD=3.0), and the time to maximum flow was 7.2 sec (SD=4.0). Subjective levels of stress did not significantly change these parameters. Uroflows were obtained with and without coffee drinking. The voided volume was 337.4 mL (SD=109.2) vs. 290.8 mL (SD=77.3) (P=0.03), and peak flow rate 19.4 mL/sec (SD=4.1) vs. 18.9 mL/sec (SD=3.1) (P=0.49), respectively. CONCLUSIONS: Uroflowmetry parameters and voided volume are highly variable in a normal asymptomatic population. Subjective stress level does not seem to have an influence on these parameters. Coffee intake significantly increases the voided volume but does not change the peak flow rate. These conclusions should be considered when using uroflowmetry parameters as an outcome measure.

Adult↗
PubMed2002

Work is a risk factor for adolescent musculoskeletal pain.

The study objectives were to determine the incidence of musculoskeletal pain in a cohort of adolescents and whether work is a risk factor for its development. 502 students in the seventh to ninth grades responded to a questionnaire at three times over a 12-month period, addressing musculoskeletal health and lifestyle factors. Annual incidence of musculoskeletal pain was 38%. Adolescents who worked developed pain more than those who did not work (adjusted odds ratio (OR): 1.62, 95% confidence interval (CI): 0.96, 2.76). Those who worked in white-collar jobs were at a higher risk of developing pain than those in blue-collar jobs or childcare. The conclusion that work is associated with musculoskeletal pain development in adolescents implies that implementation of prevention strategies in the workplace should include adolescents who work.

Adolescent↗
PubMed2002

Recommendations for the prevention of osteoporosis and fragility fractures. International comparison and synthesis.

OBJECTIVES: This review included the following objectives: a) to synthesize recommendations made by public agencies in Western countries concerning screening for osteoporosis; b) to compare these recommendations and sort out the similarities and discrepancies; and c) to propose a strategy for the fight against osteoporosis and fragility fractures. METHODS: Eleven reports published by publicly financed agencies were included in the analysis: three international, four North American and four European agencies. Transcriptions of recommendations and arguments were classified using criteria for evaluation of screening technologies. RESULTS: Of eight reports that made a recommendation on mass screening, four made a recommendation against the use of densitometry, two remained vague with a conditionally positive recommendation, and two made no recommendation, arguing insufficient scientific evidence. Concerning screening of asymptomatic women in the perimenopause period, recommendations were uniformly opposed to the use of bone densitometry in five of nine reports, and the other four made no recommendation, arguing insufficient scientific evidence. Some of the discrepancies can be explained by the different definitions given to osteoporosis and by the confusion of terms between screening and diagnostic testing. A strategy is proposed to ensure that all women who are at risk of osteoporosis and fragility fracture have access to preventive measures. This strategy is based on the complementarity and coordination of roles between health promotion interventions and clinical interventions. CONCLUSIONS: Prevention of osteoporosis and fragility fractures is an attainable goal. Existing resources are currently badly targeted. Compromises must be negotiated between the different stakeholders and biomedical disciplines to achieve efficiency and accessibility in the reduction of fragility fractures. A first compromise to reconcile social and scientific realities would be to use a best-evidence synthesis instead of an evidence-based medicine approach in future analyses and recommendations by public authorities. A second compromise would be to recognize the complementary roles of public health and clinical professionals toward the common objective of preventing fragility fractures.

Absorptiometry, Photon↗
PubMedDate not supplied

Artocarpin is a polyspecific jacalin-related lectin with a monosaccharide preference for mannose.

A reinvestigation of the carbohydrate-binding properties revealed that artocarpin, a previously described mannose-specific lectin from jackfruit (Artocarpus integrifolia) seeds, behaves as a polyspecific lectin. Surface plasmon resonance hapten inhibition experiments demonstrated that artocarpin readily interacted with a wide range of monosaccharides covering galactose, N-acetylgalactosamine, mannose, glucose, sialic acid and N-acetylmuramic acid. Molecular docking confirmed this unexpected ability of artocarpin to interact with structurally different sugars. The biological significance of the polyspecificity of the lectin is discussed in terms of the broadening of the range of potential target glycans present on the surface of plant phytopathogens or predators.

Artocarpus↗