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T Sabet

Publications and source records attributed to T Sabet.

8 recordsLinked to original sources
PubMed1993

Migration of epithelium during phenytoin-dependent gingival overgrowth in mice.

A small cavity was made in the mesiopalatal area of the maxillary first molar adjacent to the gingiva. Mice were maintained on 40 mg/kg phenytoin (or on diluent for control) by daily intraperitoneal injections. After 9 weeks, light microscopic observations revealed that in experimental mice, epithelial cells migrated towards the cavity and covered it. In controls, epithelial cell migration towards the cavity did not occur. For scanning electron microscopic (SEM) studies, specimens were fixed in 4% glutaraldehyde in 0.1 M phosphate buffer, pH 7.2, for 2 hours, dehydrated, critical point dried and coated with gold. The surface of the outer gingival epithelium of experimental and of control mice showed a honeycomb arrangement of the microridges suggesting their keratinized nature. Epithelial cells lining the cavity showed well marked macroridges along their borders. Parallel microridges were observed on the upper surface of these cells suggesting that they were non-keratinized. It was concluded that the migrating epithelial cells, that covered the cavity during phenytoin-dependent gingival overgrowth, were of the non-keratinized type.

Animals↗
PubMed1983

Phase contrast microscopy of microbial aggregates in the gingival sulcus of Macaca mulatta. Subgingival plaque bacteria in macaca mulatta.

The objective of this study was to study the relationship of microbial aggregates in the subgingival crevice to changes in periodontal health in Macaca mulatta. The sample included 68 oral sites from 17 Rhesus monkeys of various ages. The periodontal health of each site was evaluated using Plaque and Gingival Indices and crevice depth measurement. The subgingival plaque samples were examined by phase contrast microscopy and recorded on 16 mm film. A Microbial Index was developed based on a qualitative estimate of the numbers of organisms, morphology of predominant organisms, and the presence or absence of motility. The Microbial Index was demonstrated to be simple in use and highly reproducible. The findings indicate that changes in the Microbial Index are consistent with tissue changes seen in the periodontal status in M. mulatta. From this preliminary study, the oral flora of adult M. mulatta appears to have sufficient similarities to human oral flora to be used as a microbial model for experimental periodontal disease research. Future studies to refine and confirm the validity of the Microbial Index are warranted. It may prove to be a useful tool to monitor the effect of various treatment modalities on the periodontal flora and to determine the presence or absence of active disease.

Animals↗
PubMed1977

A simple method for obtaining peritoneal macrophages from chickens.

A simple technique for inducing the production of peritoneal exudate cells within 3 to 4 days in chickens is described. In each 5 to 6 week old chicken, 5 to 8 ml of washed Sephadex particles suspension in saline (3%) were injected intraperitoneally. Three to 4 days later, peritoneal exudate cells were harvested, washed, suspended in Hank's solution, counted and adjusted to one million cells per ml. In each well of 4-chamber slide 1 ml of peritoneal cell suspension was incubated at 37 degrees C for 30 min. Cultures were then gently washed several times leaving a monolayer of glass adherent cells. The phagocytic activity of these adherent cells was examined using either latex particles or antibody-sensitized sheep erythrocytes. The monolayer cells were incubated with particles in Hank's solution (with excess particles in particle/peritoneal cell ratio) for 1 h at 37 degrees C. From 99.5 to 100% of the monolayer cells were found actively phagocytic for either the latex particles or sensitized erythrocytes or both. Adherent cell monolayers were cultivated in vitro for several weeks with no detectable decrease in their phagocytic activity.

Animals↗
PubMed1975

Inhibition of melanoma growth in hamsters by type-2 adenovirus.

Type-2 adenovirus was shown to inhibit the growth of transplantable hamster melanoma in 70% of Syrian hamsters without any injurious effect to the host. Greatest inhibition of tumor formation was seen when animals were injected with 10(6) TCD50 of adenovirus and 2.5 x 10(5) tumor cells, or 10(6) TCD50 of virus and 5.0 x 10(5) tumor cells followed either 1 or 7 days later by a second injection of a similar dose of virus. Significant inhibition in tumor growth was also noted when 2 injections of virus (10(6.2) TCD50/injection) were given on 2 separate occasions as late as 7 and 10 days after the inoculation of tumor cells. The mechanism of tumor inhibition is not known but it could be due to a combination of factors such as viral toxicity, viral oncolysis, and antitumor immunity.

Adenoviridae↗