Biomedical subjects

Kayhan Basak

Publications and source records attributed to Kayhan Basak.

3 recordsLinked to original sources

PubMed2004

Lack of response to isotretinoin in annular elastolytic giant cell granuloma.

Annular elastolytic giant cell granuloma is a rare disease characterized by annular configurated lesions with typical histopathologic findings. We report a case of annular elastolytic giant cell granuloma in a 50-year-old male patient. Treatment modalities for this disease are limited and mostly unsatisfactory, although isotretinoin was found to be effective in a single case. However, systemic isotretinoin treatment of 12 weeks' duration was of no benefit in the presented case.

Administration, Oral↗

PubMed2002

An attempt to decrease ammonia levels after portacaval anastomosis in dogs: hepatic periarterial neurectomy.

Hepatic encephalopathy and elevated serum ammonia levels occur commonly after portacaval shunt and are hypothesized to be, in part, due to decreased hepatic blood flow. Prior work has demonstrated increased blood flow to the liver following hepatic periarterial neurectomy. In this experimental study, we investigated the functional, hemodynamic, and histopathological changes in the liver and kidney occurring after the addition of hepatic periarterial neurectomy to side-to-side portacaval shunt in dogs. It is our hypothesis that the addition of hepatic periarterial neurectomy to portacaval shunt will decrease postshunt ammonia levels. Side-to-side portacaval shunt was performed in 12 dogs (group I). Hepatic periarterial neurectomy was added to portacaval shunt in 9 dogs (group II). Serum levels of ammonia, urea, creatinine, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, albumin, and bilirubin together with hepatic blood flow were determined in both groups preoperatively and on postoperative day 21. The pre- and postoperative histopathologic changes of the liver and kidney were evaluated. There was significantly less postoperative elevation of serum ammonia and aspartate aminotransferase when hepatic periarterial neurectomy was added to the portacaval shunt procedure. Hemodynamic studies of hepatic artery and hepatic tissue indicated better blood flow in group II. The histopathologic evaluation of group II showed expansion of sinusoids, portal vessels, and portal areas and increased portal fibrosis as compared to group I. The results of this experimental study show that adding hepatic periarterial neurectomy to the portacaval shunt procedure improves postoperative serum levels of ammonia and aspartate aminotransferase and hepatic artery and tissue blood flow.

Ammonia↗

PubMedDate not supplied

Comparison of the effects of tretinoin, adapalene and collagenase in an experimental model of wound healing.

Adapalene is a new naphthoic acid derivative with strong retinoid agonistic pharmacological properties. We propose that adapalene might contribute to the wound repairing process as is detected with retinoids. In this controlled study, the effects of topical adapalene, tretinoin and collagenase on full-thickness wound healing were compared in an animal model. Thirty-two adult male Wistar-Albino rats were used in the study. Two circular, full-thickness wounds were made for each animal with a standard 8-mm punch biopsy, on both sides of the midline on the back. No treatment was given to Group I rats (n:8) which comprised the control group. Tretinoin cream (0.1%) was applied topically in Group II (n:8), adapalene gel (0.1%) in Group III (n:8), and collagenase ointment in Group IV (n:8) once daily. On day 7, the wounds were photographed to measure the wound surface area. The wounds on the left side of each animal were excised on day 7, for histopathologic and biochemical examination. The treatments were continued for the right side wounds up to 14 days when the same procedure was repeated. In Group II, a significant decrease in hydroxylproline (HP) levels was detected at day 7 (p = 0.018), and an increase at day 14 (p = 0.002) compared to the control group. HP results revealed no difference either in Group III nor in Group IV versus control at day 7 or 14. However, findings of improved healing were more prominent in Groups II and III than the other groups in histopathologic examination. In conclusion, tretinoin and adapalene contributed to the wound healing process resulting in an enhancement of collagen production, angiogenesis and granulation tissue formation.

Adapalene↗