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Biomedical subjects

R Zeitoun

Publications and source records attributed to R Zeitoun.

10 recordsLinked to original sources
PubMed1987

[Effect of the soft laser on gingival connective tissue. I--Effect on fibroblasts. Histoenzymology and electron microscopy study].

The effect of soft-laser upon human gingival fibroblasts was studied after an initial biopsy followed by irradiation and numerous biopsies performed 5 mn, 15 mn, 1 hour and 24 hours after irradiation. In addition, control biopsies were performed in the same way on a non-irradiated gingival area. One hour after irradiation and up to 24 hours later, the enzymatic activities of the fibroblasts were obvious: oxidative enzymes, leucine aminopeptidase, and considerable Brachet's test highly positive (RNA). By transmission electron microscopy were changes were found in these fibroblasts. They were more numerous and their cytoplasmic organelles were increased (mitochondria, rough endoplasmic reticulum). An abundant granular material as well as collagen fibrils were accumulated along their cytoplasmic membrane. On the whole, from the 1st hour on following irradiation by soft-laser a stimulation of metabolic activity of the fibroblasts (oxidative activities, proteic synthesis) was observed with increased production of collagen.

Connective Tissue Cells↗
PubMed1987

[Effect of the soft laser on gingival connective tissue. II--Effect on wound healing. Optical microscopy, histoenzymology and electron microscopy studies].

The effect of soft-laser upon cicatrization of the gum was studied in 14 patients. After the initial biopsy, control biopsies were performed on the same patients in non-irradiated gums. In the absence of inflammation, cicatrization took place in a similar manner in the irradiated and control tissues. After an early vascular growth, connective cylinders occurred, accompanied by an increase of enzymatic activity) (oxidative enzymes, leucine aminopeptidase, alkaline phosphatase). Then, the scar was formed of longitudinal bundles. The laser induced an earlier cicatrization (14th day) than in the controls (21st day). The presence of inflammation in the gum delayed cicatrization and often promoted cheloid scars with abnormal anastomosing connective bundles. In this case also, irradiation by soft-laser was followed by a quicker and better cicatrization.

Fibroblasts↗
PubMed1985

[We dentists and AIDS].

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Acquired Immunodeficiency Syndrome↗
PubMed1977

Liver monoamine oxidase (MAO) in liver homogenate of mice infected with Schistosoma mansoni and effect of certain therapeutic agents.

MAO activity in liver homogenate of mice infected with Schistosoma mansoni was determined from the second till the 14th week following infection. Significant diminution of MAO activity was noticed starting from the sixth week following infection, reaching its lowest value at the eighth week, obviously denoting progress of hepatic fibrosis. Treatment of the infected, animals with four different antischistosomal agents, tarter emetic, stibophen, niridazole and hycanthone, resulted in an improvement of the enzyme level to an almost normal value. This may indicate the ease with which the lesions in the liver including fibrosis recover when the infection is successfully treated.

Animals↗
PubMed1975

Functional capacity of the tryptophan-niacin pathway in the premenarchial phase and in the menopausal age.

Studies on the interrelationship between female hormones associated with reproduction and the vitamin B6-dependent enzymes along the kynurenin pathway of trytophan metabolism were carried out in girls with an age less, and more than 10 years (just before the onset of the first menstrual cycle), and in postmenapausal women with and without relative (excess) production of estradioll from the adrenal cortex. It is found that most of the determined metabolites are retained by the girls with age less than 10 years after tryptophan loading without and with vitamin B6 supplementation. Estradiol from either the ovaries (in girls just before menarch), or the adrenal cortex-in postmenopausal women with relative (excess) production of this hormone-interferes with the further degradation of 3-hydroxyanthranilic acid. However, this interference could be completely restored by vitamin B6 supplementation. The extra presence of a partial impairment in the kynureninase enzyme is also suggested in these postmenopausal women. In the latter case, this enzymatic activity could be partially resored by vitamin B6 supplementation. On the contrary, the enzymes: kynureninases and adrenocortical estradio. Pyridoxine supplementation partially corrected the inhibition especially that of 3-hydroxykynurenine transaminase enzyme.

Adult↗