Biomedical subjects

M Leroux

Publications and source records attributed to M Leroux.

4 recordsLinked to original sources

PubMed1992

Isokinetic rehabilitation after arthroscopic meniscectomy.

The aim of this study was to assess the effects in humans of early (2 weeks) and delayed (6 weeks) isokinetic strength training in the recovery of muscle strength following an arthroscopic partial meniscectomy. The peak torque developed in the quadriceps and hamstrings and the torque developed at a knee angle of 1.05 rad were evaluated in 16 subjects, pre-operatively (pre-op), and 2, 6, and 10 weeks post-operatively (post-op), on an isokinetic device at four different velocities (1.05, 2.09, 3.14, and 4.19 rad.s-1). The fatigue characteristics of the muscles were evaluated by having the subject perform 15 maximal contractions at 3.14 rad.s-1. Training was done on the same device (three times a week for 1-2 months), beginning either 2 or 6 weeks post-op. A repeated measures analysis of variance demonstrated a time effect but no differences between groups and no interactions. Torques developed by the knee flexors and extensors were significantly smaller 2 weeks post-op than pre-op, at all velocities tested. Torques developed in the quadriceps recovered to their pre-op values by 6 weeks, and further gained significantly in strength from 6 to 10 weeks. Quadriceps torques remained weaker than the contralateral side at 10 weeks. Hamstrings torques were either higher or similar to pre-op values by 6 weeks, and demonstrated increases from 6 to 10 weeks post-op at 1.05 and 4.19 rad.s-1 only. Total work and average power developed by the quadriceps and hamstrings during the fatigue protocol changed with time in a similar manner to torque.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1979

Decrease in lung recoil pressure after cessation of smoking.

Tests of lung mechanics and single-breath carbon monoxide diffusing capacity (DLCO) were done in 26 apparently healthy cigarette smokers before and 2 months after cessation of smoking. There was a significant increase in vital capacity and 1-sec forced expiratory volume as well as improvement in frequency dependence of lung dynamic compliance. Slope and phase III and density dependence of maximal expiratory flow showed a borderline improvement DLCO did not change. Static lung pressure-volume curves showed a small but significant (P less than 0.01) shift toward lower pressures. We concluded that the previously reported decrease in lung recoil pressure observed in smokers is even more accentuated after cessation of smoking.

Adult↗

PubMed1977

Measurement of creatine kinase Z in human sera using a DEAE-cellulose mini-column method.

A DEAE-cellulose mini-column method has been developed which allows for the quantitation in human serum of creatine kinase Z, a sub-band of creatine kinase first described by Lim ((1975) Clin. Chem. 21, 975, Abstract 181) and Sax et al. (Sax, S.M., Moore, J.J., Giegel, J.L. and Welsh, M. (1976) Clin. Chem. 22, 87). We have shown that creatine kinase Z is rather unstable in nature, and converts to a form which electrophoreses with creatine kinase MM on agarose gel electrophoresis. CK-Z is not present in normal human serum. CK-Z is present in human heart extracts, in patients with myocardial infarcts and in patients with skeletal muscle trauma. In infarct patients CK-Z levels paralleled changes in the CK-MB levels. CK-Z ranged in activity from 8.8-67.2 I.U. whereas CK-MB ranged from 29.6-121.6 I.U. in infarct patients. CK-Z and CK-MB activity were measured at or close to the peak rise in total CK activity.

Brain↗

PubMed1975

The early detection of airway obstruction.

To assess the sensitivity of tests for early, small airway obstruction, we selected 52 cigarette smokers with a ratio of 1-sec forced expiratory volume to forced vital capacity greater than 70 per cent from a smoking cessation clinic. From these subjects, 29 of the 46 tested demonstrated frequency dependence of dynamic compliance, a finding arbitrarily defined as indicative of small airway obstruction in this group. Dynamic compliance was correlated with the British Medical Research Council questionnaire, routine pulmonary function tests, closing volume as a per cent of vital capacity, maximal expiratory flow-volume curves, and flow dependence of distribution of inhaled boluses of xenon-133 (finite difference Xe). Symptoms of respiratory disease, and abnormal flow-volume curves, specific conductances, and ratios of residual volume to total lung capacity were also present in some subjects, but they correlated very poorly with frequency dependence of dynamic compliance. On the other hand, finite difference Xe was abnormal in 85 per cent of cases with frequency dependence of compliance and closing volume was abnormal in 70 per cent. In 8 of 12 subjects restudied 2 months after they stopped smoking, dynamic compliance was less frequency dependent than before smoking cessation. Similar improvements were noted in finite difference Xe, but closing volume was unchanged. Although closing volume and dynamic compliance tended to be abnormal in the same subject, concordance was not excellent, and the effects of smoking cessation suggested that the 2 tests had different determinants.

Adult↗