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Biomedical subjects

M Hassar

Publications and source records attributed to M Hassar.

30 records · Page 2Linked to original sources
PubMed1977

Free-living volunteer's motivations and attitudes toward pharmacologic studies in man.

Two groups of volunteers who had participated in pharmacologic studies were interviewed about their impressions of such studies. One group was from a university community, the other from the pharmaceutical industry. The differences between the two groups were correlated with their respective backgrounds. Both groups had favorable impressions about drug studies and investigators. Most were satisfied with the information given them about the nature and risks of the studies, but some believed that a written description of the study that they could consult at home would improve their understanding of the information. Financial reward was the primary reason given by both groups for volunteering, but the perceived risk of the study was the ultimate deciding factor. The volunteers disliked having their mobility restricted and for this reason might not be willing to participate in long-term studies, such as those formerly carried out in prisons. Alternative sources of volunteers for long-term studies will have to be found.

Adult↗
PubMed1976

"Uniformed" consent and the wealthy volunteer: an analysis of patient volunteers in a clinical trial of a new anti-inflammatory drug.

After a 16-week clinical trial of a new anti-inflammatory drug, the participants were given a factual test to determine whether they had understood and remembered the information given them when consent was solicited. They filled out a questionnaire about their reasons for volunteering and their views on clinical studies and on medical practice in general. Demographic information was also obtained. Two thirds of the participants did not remember that they had been informed about potential risk (gastrointestinal ulceration). Some subjects remembered, but misunderstood, what they had been told; others developed erroneous ideas about the trial and the study drug. The volunteers agreed to participate in the study to help both their own arthritis and that of other patients. They took pride in their self-sacrifice and in being commended by their friends for their altruism. Analysis of the demographic data shows that indigent persons are not necessarily the most likely to participate in clinical trials. Two thirds of the subjects were from the middle class. The median family income was $13,000. To improve the informed consent procedure, we recommend group meetings in which the participants in a clinical trial can discuss the protocol and the risks of the study. Obtaining consent again, after initial anxiety has decreased, may improve comprehension.

Adult↗
PubMedDate not supplied

A comparison study of two therapeutic protocols for neurosyphilis.

In Morocco, neurosyphilis is a serious public health problem. In the neurology service at the specialist hospital in Rabat, two drug treatments were used. Treatment A consisted of infusion over a period of 4 h of 20 MUI of penicillin G per day for 3 weeks. Treatment B consisted of infusion over a period of 6 h of 30 MUI of penicillin G per day for 10 days. Each treatment was tested on a group of eight neurosyphilitic patients as first-line treatment. On the first day of treatment, both blood and CSF pharmacokinetics were sampled for each patient. Blood and CSF were taken within 24 h. Penicillin G concentrations were determined by a microbiological method. The results obtained showed that perfusions of either 20 MUI or 30 MUI of penicillin allowed the achievement of high serum concentrations. These increased progressively until reaching their maximum at T4 h for treatment A (from 92.33 to 106.38 micrograms/ml). For treatment B, maximal concentration is obtained at T6 h (from 108 to 141.52 micrograms/ml). Penicillin concentrations decreased immediately after stopping the perfusion. At CSF levels, penicillin G concentrations were identical to serum concentrations. However, one difference was observed: a one-hour difference between the serum and CSF peaks. The CSF peak was achieved at T5 h for treatment A (0.063 to 2.25 micrograms/ml) and at T7 h for treatment B (0.92 to 2.94 micrograms/ml). The concentrations obtained were largely superior to the CMI of Treponema pallidum for both treatment A and treatment B, at 47 times and 82 times higher respectively. The recovery time of the patients was 14 h for treatment A and 24 h for B treatment. These results have shown that therapeutic method B was more efficient than A. Moreover, the evolution of penicillin G's diffusion in the CSF during treatment, of cell counts of protein level, of the VDRL test and of the gamma-globulin rate was studied.

Adult↗
PubMedDate not supplied

[Synthesis and pharmacologic study of 1,5-dialkyl-1,5-benzodiazepine-2,4-dithiones].

The synthesis and psychotropic activity of 1,5-diakyl-1,5-benzodiazepine-2,4-dithiones (alkyl = methyl, ethyl and benzyl radicals) were studied. Alkylation reactions were performed in catalytic conditions by phase transfer. These reactions allowed us to isolate only one kind of product N-alkyl. Acute toxicity studies were conducted according to European protocols in two species of appropriate mammals in order to discover the lethal doses. The activity of the compounds on the CNS was then studied, using a battery of compartmental tests used in psychopharmacology. No toxicity was demonstrated at therapeutic doses. Each product had a sedative effect more or less pronounced and different from the reference substance clobazam (Urbanyl). They also had myorelaxant and anxiolytic effects, even lengthening the hypnotic effect of thiopental (synergic action).

Alkylation↗
PubMedDate not supplied

Effects of saponins from Herniaria glabra on blood pressure and renal function in spontaneously hypertensive rats.

Experiments were performed on male and female spontaneously hypertensive rats weighing 310-340 g (10 animals per group). The oral administration of 200 mg/kg/day of saponins from Herniaria glabra for 30 days, resulted in a significant decrease in blood pressure in hypertensive rats. The systolic and diastolic blood pressure decreased significantly and respectively from 187.60 +/- 20.63/119.00 +/- 7.09 mmHg at day 0 (D0) to 141.60 +/- 7.51/90.40 +/- 7.68 mmHg at day 30 (D30), p < 0.001 (vs. 186.30 +/- 11.27/114.10 +/- 12.00 mm Hg at D0 to 154.50 +/- 6.38/132.3 +/- 7.68 mmHg at D30 in furosemide-treated group, p < 0.001). Control animals receiving placebo did not show any significant variation in the mean arterial pressure. The effect of saponins of Herniaria glabra on renal function was evaluated in spontaneously hypertensive rats using clearance techniques. Glomerular filtration rate was constant in the control rats and increased significantly in the hypertensive rats after saponins treatment (5.55 +/- 0.32 vs. 6.03 +/- 0.43 ml.min-1.kg-1 in the control (C) and saponins (S) groups, respectively, p < 0.05). Saponins administration provoked an increase in urinary flow (59.38 +/- 5.85 ml.kg-1.24 h-1 vs. 36.92 +/- 5.17 ml.kg-1.24 h-1, p < 0.001). Saponins also increased potassium excretion (6.89 +/- 0.81 mmol.kg-1.24 h-1 vs. 5.40 +/- 0.51 mmol.kg-1.24 h-1, p < 0.001) and sodium excretion (10.74 +/- 1.21 mmol.kg-1.24 h-1 vs. 7.25 +/- 0.54 mmol.kg-1.24 h-1, p < 0.001) as well as chloride excretion (13.59 +/- 1.04 mmol. kg-1.24 h-1 vs. 9.67 +/- 0.77 mmol.kg-1.24 h-1, p < 0.001). It is concluded that chronic oral administration of saponins from Herniaria glabra decreased the arterial blood pressure and affected salt and water transport in renal tubules.

Animals↗
PubMedDate not supplied

Antitumour principles from Peganum harmala seeds.

From ancient times, Peganum harmala was claimed to be an important medicinal plant. Its seeds were known to possess hypothermic, and essentially hallucinogenic properties. Various authors have undertaken studies on the antibacterial, antifungal and antiviral effects of Peganum harmala seeds, but studies on the antitumour activity are not to be found in the literature. In Moroccan traditional medicine, seed powder is sometimes used on skin and subcutaneous tumours. This work was designed to investigate some aspects of the antineoplastic properties of the plant Peganum. Varying concentrations (10 to 120 micrograms/ml) of total alkaloid extracts of Peganum harmala seeds (collected in Morocco) were tested in vitro on four tumoural cell-lines: Med-mek and UCP-Med carcinoma, UCP-Med sarcoma and Sp2/O-Ag14. In vivo experiments were performed with the Sp2/O cell-line grafted subcutaneously in syngenic BALB/c mice. In vitro, proliferation of tumoural cell lines was significantly reduced by all tested concentrations of the Peganum alkaloid extracts during the first 24 h of contact. A cell lysis effect occurred after 24 h and progressed to complete cell death within 48 to 72 h depending on the alkaloid concentration. Results obtained indicate that alkaloids of Peganum have a high cell toxicity in vitro. The active principle at a dose of 50 mg/kg given orally to mice for 40 days was found to have significant antitumoural activity. Peganum harmala alkaloids thus possess significant antitumour potential, which could prove useful as a novel anticancer therapy.

Alkaloids↗
PubMedDate not supplied

[Experimental evidence of an antihypertensive and hypocholesterolemic effect of oil of argan, Argania sideroxylon].

The chronic ingestion of 5 ml/kg/d of Argan oil by spontaneously hypertensive rats restores normal blood pressure and induces hypocholesterolaemia. In order to confirm these results Meriones shawi, a rodent of the Gerbillideae family, was tested as a second animal model. Meriones submitted to a hypercaloric diet and physical inactivity became fat, and exhibited hypertension, dyslipidaemia and hyperinsulinaemia. When treated for two months with the same dosage regimen, decreases in glycaemia, total plasmatic cholesterol, LDL, insulinaemia and systolic and diastolic blood pressures of 4.4 per cent, 14.4 per cent, 32.5 per cent, 26.8 per cent, 28.8 per cent and 30.5 per cent were simultaneously observed. Increases in LDH and of TG of 27.9 per cent and 16.2 per cent respectively were also observed. No effect on body weight occurred. The action of polyunsatured fatty acids of the Argan oil is predominant, but in addition, other constituents play an active part.

Animals↗
PubMedDate not supplied

[Diuretic and hypotensive effects of Nigella sativa in the spontaneously hypertensive rat].

Nigella sativa (ranunculaceae) is used in Arab folk medicine as a diuretic and hypotensive plant. We report here the diuretic and hypotensive effects of dichloromethane extract of Nigella sativa seeds in the spontaneously hypertensive rat (SHR). An oral dose of Nigella sativa extract (0.6 ml/kg/day) and furosemide (5 mg/kg/day) increased significantly the diuresis by 16 and 30 per cent respectively after 15 days of treatment; urinary excretion of Cl-, Na+, K+ and urea is also increased. Simultaneously, the mean arterial pressure decreased respectively by 22 and 18 per cent in the Nigella sativa treated rat and nifédipine treated rat (0.5 mg/kg/day). In conclusion, the diuretic activity observed in the SHR rat treated with Nigella sativa seeds may be partially responsible for its diuretic action; it seems that other pathways may also be involved in their cardiovascular effects.

Animals↗