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C Simard

Publications and source records attributed to C Simard.

At least 145 records · Page 8Linked to original sources
PubMedDate not supplied

Immunization with a peptide derived from the G glycoprotein of bovine respiratory syncytial virus (BRSV) reduces the incidence of BRSV-associated pneumonia in the natural host.

Previous reports demonstrate that synthetic peptides corresponding to the amino acid region 174-187 of G glycoprotein from subgroups A and B human respiratory syncytial virus (HRSV), containing a Cys-->Ser substitution at position 186, confer complete resistance to immunized BALB/c mice against infection with the respective virus. In this report, we show that a Cys186-->Ser substituted peptide (BG/174-187) representing the corresponding region of the bovine (B) RSV G glycoprotein conferred complete protection of mice against BRSV challenge, suggesting that the 174-187 region of RSV G glycoproteins constitutes a dominant protective epitope which has been maintained throughout evolution. Furthermore, immunization of calves with peptide BG/174-187 efficiently induced the production of antibodies capable of recognizing both the parental G glycoprotein and peptide BG/174-187. Following challenge with live BRSV, although none of the animals were protected from upper respiratory tract disease, there were little or no gross pneumonic lesions in the four peptide-immunized calves. In contrast, moderate to extensive pneumonic lesions were observed in 2 out of 3 calves in the control group. Our results thus suggest that peptide BG/174-187 efficiently prevented BRSV-associated pneumonia in the natural host. The use of this system as a model is quite promising with regard to the development of a human synthetic vaccine.

Animals↗
PubMedDate not supplied

Identification of the cytochrome P450 enzymes involved in the metabolism of domperidone.

The objective was to identify the major cytochrome P450 enzyme(s) involved in the metabolism of domperidone. Experiments were performed using human liver microsomes (HLMs), recombinant human cytochrome P450 enzymes, cytochrome P450 chemical inhibitors and monoclonal antibodies directed against cytochrome P450 enzymes. Four metabolites were identified from incubations performed with HLMs and excellent correlations were observed between the formation of domperidone hydroxylated metabolites (M1, M3 and M4), N-desalkylated domperidone metabolite (M2) and enzymatic markers of CYP3A4/5 (r2 = 0.9427, 0.951, 0.9497 and 0.8304, respectively). Ketoconazole (1 microM) decreased the formation rate of M1, M2, M3 and M4 by 83, 78, 75 and 88%, respectively, whereas the effect of other inhibitors (quinidine, furafylline and sulfaphenazole) was minimal. Important decreases in the formation rate of M1 (68%), M2 (64%) and M3 (54%) were observed with anti-CYP3A4 antibodies. Formation of M1, M2 and M3 in HLMs exhibited Michaelis-Menten kinetics (Km: 166, 248 and 36 microM, respectively). Similar Km values were observed for M1, M2 and M3 when incubations were performed with recombinant human CYP3A4 (Km: 107, 273 and 34 microM, respectively). The data suggest that CYP3As are the major enzymes involved in the metabolism of domperidone.

Cells, Cultured↗
PubMedDate not supplied

Chronic obstructive pulmonary disease: capillarity and fiber-type characteristics of skeletal muscle.

BACKGROUND: The purpose of this investigation was to compare capillarity and fiber type proportions of the vastus lateralis muscle between patients with chronic obstructive pulmonary disease (COPD) and healthy subjects. METHODS: Fifteen male subjects were included in the study (8 COPD: 61.0 +/- 1.8 years [mean +/- SEM]; forced expiratory volume in 1 second 42.0 +/- 2.1% predicted; 7 N: age 54.0 +/- 1.1). Subjects were submitted to a symptom-limited maximal exercise test on ergocycle. After a transcutaneous biopsy of the vastus lateralis muscle, sections were cut 8 to 10 microns thick and stained with the Andersen method for capillarity and Stevens method for fiber typing. RESULTS: Patients with COPD had a decrease in peak oxygen consumption compared with healthy subjects (1.2 +/- 0.1 versus 3.0 +/- 0.2 L/min). Number of capillaries per square millimeter was lower in patients with COPD versus healthy subjects (92.6 +/- 16.1 and 213.3 +/- 33.5, P < 0.001); percentages of fiber types were 43.5 +/- 5.5% type I, 56.5 +/- 5.5% type II in COPD, and 56.7 +/- 3.4% type I, 43.2 +/- 3.4% type II in healthy subjects (P < 0.05). In addition, capillaries/fiber ratio was 0.83 +/- 0.05 in COPD, and 1.56 +/- 0.10 in healthy subjects (P < 0.001). CONCLUSION: As expected, patients with COPD showed a decrease in exercise capacity. The muscle analysis results indicate that patients with COPD have a greater proportion of type II fibers and a much lower capillaries/fiber ratio than normal subjects. We conclude that COPD adversely affects fiber type and capillarization of the lower limbs. This could be partly caused by deconditioning in these patients.

Adult↗
PubMedDate not supplied

[Report of a case of Gaucher's disease in adult].

The authors report a case of Gaucher's disease in an adult. This is a rare disease due to the accumulation of a glucoceramide in the reticulo-endothelial cells and may remain for long clinically symptomless, as in this case. The diagnosis suggested by the biological disturbance, viz. moderate thrombopenia, hypergammaglobulinemia, increase in SGPT, was conformed by the presence of Gaucher's cells in the liver and in the bone marrow, and by the existence of an intraleukocytic glucosidase deficiency. The authors recall the clinical forms of this disease, and recent clinical trials.

Adult↗
PubMedDate not supplied

[Primary intestinal lymphangiectasis or Waldmann's disease (author's transl)].

The authors report the observation of a primary intestinal lymphangiectasy diagnosed on a young girl sent for isolated edema of her inferior members, recently appeared. Clinical examination was normal. Biology found a low protein rate at 33 g/l and a low lymph rate : 183 L/mm3. Hepatic and renal records were normal. Test to marked albumin asserted the exsudative enteropathy with a fecal radio-activity of 3.6% (N 1%). Biopsy of the small intestines set out lymphangiectasies of the intestinal mucosa. Referring to this observation and to literature date, the authors realise a clinical and physiopathological analysis of Waldmann's disease or primary intestinal lymphangiectasy.

Adult↗
PubMedDate not supplied

[Exercise test before prosthesis fitting in amputees with vascular insufficiency].

93 subjects (age = 65 +/- 10 years) with lower limb amputation ensuing from peripheral vascular disease performed a graded exercise test on arm cranking ergometer with an electromagnetic braking to assess their physical fitness and cardiac condition before starting a prosthetic training programme. The protocol was continuous with a workload increment of 10 watts every two minutes. Heart rate, blood pressure and ECG were recorded at each stage. Reasons to stop the test were 1) arm muscle fatigue, 2) reaching of target heart rate, 3) cardiovascular abnormalities. At the end of the test, the mean percentage of maximum heart rate was 53%, 92%, and 66% for each of these reasons, respectively (p less than .0001). Results showed that subjects who received a prosthesis had a higher exercise capacity than those who did not get a prosthesis (39.0 watts vs 18.5 watts, p less than 0.001). Furthermore, maximal oxygen uptake (4.4 METs vs 3.0 METs, p less than 0.001) and reached maximal heart rate (131 vs 110 bpm, p less than .005) were both higher in subjects of prosthesis group. Results suggest that a graded exercise test at the beginning of prosthetic training allows a rehabilitation team 1) to predict the success of the prosthetic process and 2) to identify subjects for which this process could increase the risks of health problems.

Aged↗
PubMedDate not supplied

[Aortic sarcoma. A rare pathology].

In the light of a case of endotheliosarcoma of the thoracic aorta, the authors found in the literature 33 cases of aortic sarcomas and 13 of sarcomas of peripheral arteries. The clinical diagnosis of this rare tumor is difficult. The diagnosis can be made before surgery only on the basis of angiographic and CT scan findings, whilst in most instances common arterial lesions are suspected whether of atheromatous or embolic origin. The positive diagnosis of arterial sarcoma remains histological. The diagnosis of an endothelial tumor can be made with the help of the techniques of factor VIII, antigen H and, more recently, lectins. Surgical treatment by excision and restoration of continuity has most often been used. Alone or in combination with chemo and/or radiotherapy, it would seem to be inadequate to prevent progression which involves the invasion of adjacent tissues, tumor emboli or generalized metastases. The prognosis of such a tumor remains gloomy with an average life expectancy of one year and 7 months, regardless of the histological type of arterial sarcoma.

Aged↗
PubMedDate not supplied

[Primary aortoduodenal fistula of tuberculous origin].

This case of aorto-duodenal fistula was due to fistulization of a tuberculous lymph node between an atheromatous aneurysm of the infra-renal aorta and the third part of the duodenum. CAT scan provided the diagnosis of an aorto-duodenal fistula. The tuberculous origin of the fistula was confirmed by bacteriological and histological examinations. The outcome was favourable after revascularisation "in situ" combined with epiplooplasty and prolonged antituberculous drug therapy.

Aged↗