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Biomedical subjects

M Hassar

Publications and source records attributed to M Hassar.

At least 19 recordsLinked to original sources
PubMed2002

Intraspecific variability and pharmacokinetic characteristics of Androctonus mauretanicus mauretanicus scorpion venom.

We evaluated the degree of venom toxicity and protein content of several specimens of Androctonus mauretanicus mauretanicus. The quantity of protein of individual venom obtained after manual extraction from 31 different scorpions varied from a minimum of 0.15 mg to a maximum of 1.53 mg. We determined the venom toxicity, in mice, by estimating the number of LD(50)s of 20 scorpions chosen randomly among the 31 scorpions. It ranged from less than 40 LD(50)s to a maximum of 272 LD(50)s. The correlation between protein content and venom lethality is not systematic. We also determined the pharmacokinetics of the venom and its specific anti-venom in rabbits to compare their distribution and elimination properties. After a subcutaneous injection, high concentrations of venom were measured by ELISA in the vascular space rapidly after the injection (T(max) = 0.5 h). The terminal half-life was 2.8 h, close the one determined after intravenous injection (t(1/2beta) = 3.2 h). The total volume of distribution (Vd(ss) or Vd(beta)) was between 317 and 380 ml/kg. The total body clearance was 82 ml/kg/h. For scorpion anti-venom, the terminal half-life, after intravenous injection, was 20.25 h; the volume of distribution was 83 ml/kg and the total body clearance was 3 ml/kg/h. After intramuscular administration, T(max) was reached at 36 h. The results show that venom lethality varies from specimen to specimen and that pharmacokinetic parameters of venom and anti-venom are totally different. This must be taken under consideration in anti-venom production (anti-venom titre) as well as in therapeutic protocols (dose, injection route) to improve serotherapy.

Animals↗
PubMed2002

Effects of Nigella sativa fixed oil on blood homeostasis in rat.

We investigated the effects of the fixed oil of Nigella sativa seeds in rats by monitoring blood homeostasis and body weight as well as toxicity. Animals were treated daily with an oral dose of 1 ml/kg body weight of the N. sativa seed fixed oil for 12 weeks. Changes in key hepatic enzymes levels were not observed in N. sativa treated rats after 12 weeks of treatment. The serum cholesterol, triglycerides and glucose levels and the count of leukocytes and platelets decreased significantly by 15.5, 22, 16.5, 35 and 32%, compared to control values, respectively; while haematocrit and haemoglobin levels increased significantly by 6.4 and 17.4%, respectively. In parallel, significant slowdown of the body weight evolution was observed in N. sativa treated animals comparatively to the animal control group. On the other hand, no mortality was noted for ten times the therapeutic dose in mice, during 15 days period after the oil administration (10 ml/kg p.o.). These results support the traditional use of N. sativa seeds as a treatment of the dyslipidemia and the hyperglycaemia, and related abnormalities; however, indicate a relative toxicity of this plant. Acute and chronic toxicity, and the mode of the action of the N. sativa fixed oil must be studied.

Animals↗
PubMed2002

Acute and chronic toxicity of Nigella sativa fixed oil.

We investigated the toxicity of the fixed oil of Nigella sativa L seeds in mice and rats through determination of LD50 values and examination of possible biochemical, hematological and histopathological changes. The acute toxicity of Nigella sativa fixed oil was investigated in mice. LD50 values, obtained by single doses, orally and intraperitoneally administered in mice, were 28.8 ml/kg body wt. p.o. [26.2-31.6] and 2.06 ml/kg body wt. i.p. [1.86-2.26], respectively. Chronic toxicity was studied in rats treated daily with an oral dose of 2 ml/kg body wt. for 12 weeks. Changes in key hepatic enzymes levels, including aspartate-aminotransferase, alanine-aminotranferase, and gamma-glutamyltransferase and histopathological modifications (heart, liver, kidneys and pancreas) were not observed in rats treated with Nigella sativa after 12 weeks of treatment. The serum cholesterol, triglyceride and glucose levels and the count of leukocytes and platelets decreased significantly, compared to control values, while hematocrit and hemoglobin levels increased significantly. A slowing of body weight gain was also observed in Nigella sativa treated rats, as compared to control animals. The low toxicity of Nigella sativa fixed oil, evidenced by high LD50 values, key hepatic enzyme stability and organ integrity, suggests a wide margin of safety for therapeutic doses of Nigella sativa fixed oil, but the changes in hemoglobin metabolism and the fall in leukocyte and platelet count must be taken into consideration.

Acute Disease↗
PubMed2002

Experimental toxicity of Peganum harmala seeds.

Peganum harmala is plant known since the first century A.D. and still, currently used for therapeutic purposes. Harmaline, the active principle of the plant seeds, and its derivatives, cause visual troubles, loss of coordination, agitation and delirium, and, at high doses, it can produce paralysis. The present study was initiated to evaluate the use and manipulation of therapeutic doses of aqueous extract of P. harmala. Wistar rats were orally dosed acutely and the LD(50) obtained was 2.70+/-0.05g/kg. In chronic studies aqueous extract of P. harmala administered orally for six times a week at doses of 1, 1.35 and 2g/kg during 3 month period increased transaminases. Changes in glucose and creatinine were not significant. No significant gross changes were found at necropsy. Histologic study showed liver degeneration and spongiform changes in the central nervous system (CNS) in rats treated with 2g/kg dose but not at the therapeutic dose of 1g/kg.

Animals↗
PubMed2001

[Antihypertensive effect of Herniaria glabra saponins in the spontaneously hypertensive rat].

We studied the antihypertension action of Herniaria glabra saponins and compared the effect with that of furosemide. Spontaneously hypertensive rats were treated with H. glabra saponins at a dosage of 200mg/Kg of body weight. Treatment led to progressive decline in both systolic and diastolic blood pressures. After one month of therapy, pressures were: 141,60+/-7,51 / 90,40+/-5.46mmHg versus 187,60+/-5,94/119,10+/-7.79mmHg (p<0,001). We did not observe any change in heart rate. H. glabra saponins were able to lower blood pressure by a multifactorial mechanism.

Animals↗
PubMed2000

In vitro cell-toxicity of Peganum harmala alkaloids on cancerous cell-lines.

The alkaloidic fraction of the methanol extract of Peganum harmala seeds was tested in vitro on three tumoral cell-lines: UCP-Med and Med-mek carcinoma, and UCP-Med sarcoma. Proliferation was significantly reduced at all tested concentrations (20-120 micrograms/ml) during the first 24 h of contact. A cell lysis effect occurred after 24 h and increased thereafter to complete cell death within 48-72 h, depending on tested concentration.

Alkaloids↗
PubMed1998

[Acute and chronic toxicity of saponins from Argania spinosa].

We evaluated the acute and chronic experimental toxicity of a water extract of saponins from Argania spinosa following oral and intraperitoneal (i.p.) administration in mice (Iops Ofa) and rats (Wistar). The DL50 obtained were 79 mg/kg for the i.p. route and 1,300 mg/kg for the oral route. For the chronic toxicity studies, we administred 100 and 200 mg/kg orally once a day during a 3 month period. There was a decrease in blood sugar in the third month of each therapy. Blood creatinine levels increased, thus evoking a renal pathology. A slight increase in transaminases levels was not significatif. Hematologic parameters were unchanged during the treatment and the histopathologic study showed hepatic glycogen decrease and a focal renal tube deterioration.

Administration, Oral↗
PubMed1998

[Analgesic and anti-inflammatory activity of saponins of Argania spinoza].

We studied analgesic and antiinflammatory actions of saponins of Argania spinosa cakes in mice and rats. With oral doses of 50 to 300 mg/kg, we found peripheric analgesic actions equivalent to the acetyl salicylic acid ones. The maximum protection was obtained with 500 mg/kg per os. There is no morphine-like central analgesic effect. Antiinflammatory studies were done in vivo using oedema due to carrageenine or experimental trauma in rats. There was a decrease in the paw swelling at doses of 10 mg/kg per os. At doses of 50 to 100 mg/kg per os, the antiinflammatory effect was similar to the one of indomethacin at doses of 10 to 20 mg/kg per os. In vitro, there was an inhibition of beef synovial fluid degradation by OH. radicals. The inhibition action is evaluated with an IC20 > or = 6 microM. Argania spinosa saponins have also an antiradical action against DPPH (IC25 = 85 mM) and against OH. radicals (IC25 = 0.56 M). Since they do not have any inhibition effect on PGE2 synthesis, their antiinflammatory activity can be explained by their action on leucotriens in the metabolic pathway of arachidonic acid.

Analgesics↗
PubMed1978

The rate of development of new drugs in the United States, 1963 through 1975.

Information was obtained on 1,103 new chemical entities (NCEs) first tested in man from 1963 through mid-1975 by 36 U. S.-owned and 10 foreign-owned pharmaceutical companies operating in the U. S. Of these NCEs 1,029 reached the stage of IND filing. The portion of the U. S. industry responsible for the NCEs was relatively concentrated; 7 of the 36 companies accounted for half of the NCEs and 4 of these accounted for one-third. Although the annual worldwide rate of testing of NCEs by U. S. companies appeared to rise and then fall from 1963 through 1966, since 1966 the rate has been fairly constant. With time, however, a higher proportion of U. S.-owned NCEs is being first studied in man abroad. The annual rate of IND filings for U. S.-owned NCEs generally declined from 1965 to 1972, whereas the rate was fairly constant for foreign-owned NCEs over the entire period. The overall success rate in drug development has been low; nearly 90% of the NCEs studied in man are dropped prior to NDA submission, but about 88% of the NDAs submitted are approved for market. The 1974-1975 data indicate that the mean durations of the IND and NDA phase were then 4 and 2 years, respectively. However, there were variations in the time required for DNA approval between different pharmacologic areas. The data described in this paper represent the first baselines against which future trends in the processes of drug development and approval can be measured.

Chemistry, Pharmaceutical↗