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M Rouleau

Publications and source records attributed to M Rouleau.

48 records · Page 3Linked to original sources
PubMed1981

Effects of dilution rates, animal species and instruments on the spectrophotometric determination of sperm counts.

Using semen from bull, boar and stallion as well as different spectrophotometers, we established the calibration curves relating the optical density of a sperm sample to the sperm count obtained on the hemacytometer. The results show that, for a given spectrophotometer, the calibration curve is not characteristic of the animal species we studied. The differences in size of the spermatozoa are probably too small to account for the anticipated specificity of the calibration curve. Furthermore, the fact that different dilution rates must be used, because of the vastly different concentrations of spermatozoa which is characteristic of those species, has no effect on the calibration curves since the dilution rate is shown to be artefactual. On the other hand, for a given semen, the calibration curve varies depending upon the spectrophotometry used. However, if two instruments have the same characteristic in terms of spectral bandwidth, the calibration curves are not statistically different.

Animals↗
PubMed1980

Facial nerve reconstruction.

A retrospective study on 21 patients who had a reconstruction of their facial nerve was undertaken by means of a new photographic method of evaluation. The average of recuperation results was 62.38 per cent. Eighty-five per cent of the patients achieved a good or excellent evaluation. The only individual parameter that showed some influence on the outcome of the surgery was the length of the graft. Compared with a short graft (smaller than or equal to 1 cm), the long graft (larger than or equal to 1 cm) is associated with better results. Good and excellent results appeared available for patients whose pre-operative palsy had lasted from 18 to 36 months.

Adolescent↗
PubMed1978

Arrest of synthesis of specific proteins at the onset of mammary tumor regression.

MTW9 mammary carcinoma regressing after removal of mammotropin stimulation was used as a model to test the hypothesis that the augmented activity of lysosomal enzymes observed during regression may be triggered by a modification of the protein composition of the cytoplasm. In support of the hypothesis, we observed that: (a) the pattern of leucine incorporation into cytosol proteins differs between growing and regressing tumors; (b) the difference is localized in three bands of the electrophoretic pattern; and (c) the change in pattern appears within 6 hr after hormone removal, about 4 hr after prolactin levels in blood were below the concentration needed by MTW9 to grow. These observations are in line with our previous finding of an increased susceptibility of cytosol proteins to proteolytic digesion during MTW9 regression.

Adenocarcinoma↗
PubMed1977

[Comparison between two current methods of surgical treatment for otosclerosis].

Statistical comparison is established between two methods of stapedectomy, the first one being the "Teflon-interposition", the second being Schuknecht's method (gelfoam and preformed wire). There is statistical evidence that the Teflon-interposition method is better. The results are also compared with those of other workers.

Adult↗
PubMed1977

Increased susceptibility of cytosol proteins to proteolytic digestion during regression of a hormone-dependent mammary tumor.

Regression of MTW9 mammary carcinoma, which consistently follows withdrawal of mammotropic hormones, was characterized by a rapid decrease of thymidine incorporation into DNA but only a slight reduction or uridine incorporation into RNA and amino acid incorporation into proteins. Within 24 hr of hormone withdrawal, cytosol proteins of MTW9 became more easily degraded by trypsin, alpha-chymotrypsin, or subtilisin BPN'. Labilization of cytosol proteins occurred much earlier than any change in the level of protein synthesis or lysosomal enzyme activity. The data showing increased susceptibility to proteolysis could not be explained either by the presence of endogenous proteases, by the destruction of the exogenous proteases used in the assay, or by the existence of protease inhibitors. Nor were any differences detected either in the distribution of radioactive precursor among the cytosol proteins from growing or regressing tumors or in the electrophoretic pattern of the same proteins. Preincubation of the cytosol proteins with dithiothreitol or with prolactin, 17 beta-estradiol, progesterone, and hydrocortisone did not modify the susceptibility to proteolysis. However, after heat denaturation, cytosol proteins of regressing and growing tumors became equally susceptible to proteolysis. It is suggested that regression of MTW9 mammary carcinoma occurs not only because cell reproduction is arrested, but also because susceptibility of cytosol proteins to proteolysis is increased.

Animals↗
PubMed1975

Purification and characterization of a trypsin inhibitor from Solanum tuberosum.

A trypsin inhibitor isolated from a potato acetone powder has been purified by affinity chromatography. This protein inhibits trypsin mole per mole. To a lesser extent it combines also with chymotrypsin and elastase. For trypsin, K1 = 8 X 10(-7) M. The inhibitor has a single polypeptide chain of 207 amino acid residues. It contains no sugar or free sulfhydryl groups. Its extinction coefficient E2801% = 10.3 and its isoelectric point is 6.9. Its molecular weight is of the order of 21 000-22000, as determined by sedimentation equilbrium, by inhibition experiment or from its amino acid composition. These same techniques, taken together with the single band observed at different pH on polyacrylamide gel electrophoresis, indicate that the protein purified is monodisperse. However, the finding of two N-terminal amino acid residues, leucine and aspartic acid, and the different stoichometry observed during the interaction of the inhibitor, either with trypsin or with chymotrypsin and elastase, raises the possibility that our preparation is contaminated by a polyvalent inhibitor not detectable by physiochemical methods.

Amino Acids↗
PubMedDate not supplied

Sonographic detection of ingested foreign bodies in the inferior vena cava.

Ingested foreign bodies usually proceed uneventfully through the intestinal tract; complications rarely occur. The wide variety of clinical presentations they produce often make the diagnosis difficult. We report two cases of sonographic detection of foreign bodies in the inferior vena cava, namely one toothpick and one small (chicken?) bone, which probably caused a duodenocaval fistula. Both patients were initially investigated for recurrent septic episodes, weight loss, and deterioration of general condition.

Adult↗
PubMedDate not supplied

Antibody-mediated endocytosis of G250 tumor-associated antigen allows targeted gene transfer to human renal cell carcinoma in vitro.

Specific gene transfer into targeted tumor cells remains a critical issue for the development of systemic gene therapy protocols. With this end in view, we have tested the possibility of selectively directing genes to tumor cells through the recognition of tumor-associated antigens (TAA). This was approached in vitro on four human renal cell carcinoma (RCC) lines by means of the highly specific mouse G250 monoclonal antibody (mAb) chemically conjugated to a plasmid DNA conveying a reporter activity. This mAb directed to a TAA that is present on 95% of primary RCCs and on 60% of metastatic human RCCs was extensively characterized, including during clinical trials. Epifluorescence microscopy analysis indicated that upon specific binding to G250 TAA, G250 mAb alone or conjugated to plasmid DNA was internalized by an active endocytic process and colocalized with the transferrin concentrated in the late recycling perinuclear compartment. We also observed that both unconjugated G250 mAb or G250 mAb conjugated to plasmid DNA remained in the perinuclear region of the cells for > or = 20 hours and were not rapidly translocated to lysosomes or recycled to the plasma membrane. In contrast, unconjugated plasmid DNA was not internalized. After transfection of G250 TAA-positive RCC lines with G250 mAb conjugated to a plasmid cDNA encoding mouse interleukin-2, a significant and sustained production of mouse interleukin-2 protein was detected from days 5-15 and was abrogated by inhibiting the internalization process. Altogether, our data showed that endocytosis of G250 TAA should be the basis of gene transfer to RCC, suggesting that targeting of TAA capable of internalization may be the basis of new approaches for designing alternative cancer gene therapy procedures.

Animals↗
PubMedDate not supplied

Influence of asthma education on asthma severity, quality of life and environmental control.

BACKGROUND: Several studies have examined the influence of asthma education, focusing mainly on the use of health services. OBJECTIVES: To assess the influence of an asthma education program (AEP) on airway responsiveness, asthma symptoms, patient quality of life (QOL) and environmental control. DESIGN: A prospective, randomized, controlled study with parallel groups. SETTING: Three tertiary care hospitals in Quebec. POPULATION: One hundred and eighty-eight patients with moderate to severe asthma. INTERVENTION: After optimization of asthma treatment with inhaled corticosteroids, patients were randomly assigned to receive either an education program based on self-management (group E) or usual care (control group C). RESULTS: One year after an AEP, there was a significant decrease in the number of days per month without daytime asthma symptoms in group E only (P=0.03). Asthma daily symptom scores decreased significantly in group E in comparison with group C (P=0. 006). QOL scores improved markedly in both groups after treatment optimization during the run-in period (P<0.01). After an AEP, the QOL score increased further in group E patients in comparison with group C patients (P=0.04). The concentration of methacholine that induces a 20% fall in forced expiratory volume in 1 s (PC20) improved significantly in both groups (group E 1.2+/-1.1 to 2.4+/-0. 2, group C 1.5+/-1.2 to 2.4+/-1.3, P<0.01). After one year, 26 of 37 patients from group E sensitized to house dust mites (HDM) adopted the specific measures recommended to reduce their exposure to HDM, while none of the 21 subjects from group C did (P<0.001). Among the patients sensitized to cats or dogs, 15% of patients from group E and 23% of patients in group C no longer had a pet at home at the final visit (P>0.5). CONCLUSIONS: One year after the educational intervention, it was observed that the program had added value over and above that of optimization of medication and regular clinical follow-ups. The education program was highly effective in promoting HDM avoidance measures but minimally effective for removing domestic animals, suggesting that more efficient strategies need to be developed for the latter.

Albuterol↗
PubMedDate not supplied

IL-2-R beta expression and function within resting CD8+ T cells preferentially segregate with the CD45R0+ subset.

Human peripheral blood CD8+ T cells constitutively express a low level of IL-2-R beta chains which were shown in this study to be preferentially carried by the CD45R0+ subset. Such receptors can transduce signals for in vitro IL-2-induced cytolytic function and for the initiation of soluble anti-CD3 and IL-2-induced cell proliferation. Using these stimulation models, a comparison was made between the responsiveness of resting, small CD45R0+ and CD45RA+ subpopulations of CD8+ T cells, both of them being isolated by negative selection and rigorously depleted of monocytes and of IL-2-inducible non-MHC-restricted CTL. Strong proliferation was induced in CD8+/CD45R0+ cells in response to IL-2 and soluble anti-CD3 (each of these stimuli being by itself ineffective), while in contrast, CD8+/CD45RA+ cells manifested, in this system, little reactivity. Accordingly, no conversion to the CD45R0 phenotype occurred in single stained CD45RA+ T cells following their incubation with the stimuli. A similar restriction of reactivity to CD8+/CD45R0+ T cells was observed with respect to IL-2-induced targetable T cell cytotoxicity. The CTL activity induced by IL-2 alone occurred without cell division. In contrast, the additional increase in CTL activity occurring upon the synergistic actions of anti-CD3 mAb and IL-2 coincided with intense cell proliferation, with no generation of LAK activity. The inhibition exerted by anti-IL-2-R beta mAb in the cytolytic and the proliferative activities induced by these stimuli in resting CD8+/CD45R0+ T cells emphasizes the importance of constitutive IL-2-R beta chains in the biology of these cells.

Antigens, CD↗