Biomedical subjects

Ayhan Koyuncu

Publications and source records attributed to Ayhan Koyuncu.

14 recordsLinked to original sources

PubMed2006

The intratumoral microvessel density and expression of bFGF and nm23-H1 in colorectal cancer.

It has previously been reported that intratumoral microvessel density (IMD), and the expression of bFGF and nm23-H1 are useful prognostic markers in colorectal cancer (CRC). In this study, a total of 100 CRCs were evaluated histopathologically, and IMD, bFGF and nm23-H1 expression were assessed by immunohistochemistry. IMD of patients increased with grade and stage, and this increase was statistically significant (p<0.05). A significantly higher incidence of high bFGF expression scores was also associated with increasing grade and stage (p<0.05). However, there was no significant difference between the grades in nm23-H1 expression (p=0.234). nm23-H1 expression occurred with lower incidence in stages C1, C2 and D than in stages B1 and B2 (p<0.05). Thus, a negative correlation was found between nm23-H1 expression and stage or lymph node metastasis (LNM) (p<0.05). IMD and bFGF expression were positively correlated with grade, stage, LNM, and lymphovascular invasion. Although positive correlation was found between IMD and bFGF, nm23-H1 expression negatively correlated with both of them. As a result, in clinical practice, increased IMD and bFGF expression and decreased nm23-H1 expression may provide valuable information in characterizing the malignant phenotype.

Biomarkers, Tumor↗

PubMed2005

Enhancement of EFS-induced contractions, by agmatine, in guinea pig gallbladder smooth muscle strips.

BACKGROUND: Electrical field stimulation of gallbladder muscle strips produces frequency-dependent contractions by activating cholinergic nerves. The cholinergic motor function of the gallbladder and enteric system is also modulated by other mediators. The aim of this study was to investigate the role of agmatine, a ligand for alpha 2-adrenoceptors and imidazoline binding sites, in the cholinergic motor activity of guinea pig gallbladder smooth muscle. METHODS: Gallbladder muscle strips obtained from guinea pigs were subjected to electrical field stimulation (1-64 Hz, 100 V, 1-ms pulse width, and 10-s train duration). Frequency-response contractions of gallbladder muscle strips were traced before and after the addition of cumulative concentrations of agmatine (10(-5)-10(-3) M) to the tissue bath. The same set of experiments was repeated in the presence of different antagonists. RESULTS: Agmatine by itself did not produce any contractions in guinea pig gallbladder muscle strips, but significantly enhanced the contractile response produced by electrical field stimulation. Yohimbine (10(-6) M), a selective alpha 2-adrenergic blocker, neither decreased nor increased the enhancement induced by agmatine. However, idazoxan (10(-4) M), an alpha-receptor blocker and imidazoline receptor antagonist, abolished this enhanced contractile response. Pretreatment with N(W)-nitro L-arginine methyl ester (L-NAME; 30 microM), and indomethacin (10 microM) did not inhibit the effect of agmatine. CONCLUSIONS: Our findings indicate that agmatine has a modulator role in the electrical field stimulation-induced cholinergic contractions of guinea pig gallbladder smooth muscle strips, and this role could be mediated by imidazoline receptors. Receptor binding studies should be done to determine the presence of endogenous agmatine and imidazoline receptors in gallbladder smooth muscle.

Agmatine↗

PubMed2004

Management of an esophagogastric fibromatosis in a child: a case report.

Intraabdominal fibromatosis is an uncommon neoplasm. The aggressive nature of these tumors and the potential for major morbidity secondary to resection can present a difficult surgical dilemma. A 9-year-old boy presented with anemia and vomiting. He had esophagogastric fibromatosis diagnosed and underwent distal esophagectomy, total gastrectomy, Hunt-Lawrence jejunal pouch, and Roux-en-Y esophagojejunostomy. This report describes the successful surgical management of an esophagogastric fibromatosis for the first time in the English-language literature. The management of this tumor is discussed with particular regard to the very unusual clinical presentation.

Abdominal Pain↗

PubMed2003

Relaxation effects of adrenomedullin in carbachol-precontracted rabbit internal anal sphincter.

BACKGROUND: The internal anal sphincter is a specialized continuation of the circular smooth muscle layer of the rectum. It has been found that internal anal sphincter tonus is significantly increased in the majority of patients with anal fissure. Adrenomedullin has a relaxant effect on smooth muscle in different kinds of tissue. In this in vitro study, we aimed to investigate whether adrenomedullin had a relaxant effect on isolated rabbit internal anal sphincter, and the possible involvement of nitric oxide, prostaglandins, and K(+) channels. METHODS: Internal anal sphincter smooth muscle strips obtained from New Zealand rabbits were studied in vitro. The effects of adrenomedullin were investigated in isolated strips of rabbit internal anal sphincter smooth muscle precontracted with carbachol alone, and in the presence of indomethacin (a cyclooxygenase inhibitor), N(omega)-nitro- l-arginine methyl ester ( l-NAME; a nitric oxide synthetase inhibitor), and K(+) channel blockers. RESULTS: Adrenomedullin caused relaxation of the isolated precontracted rabbit internal anal sphincter strips in a concentration-dependent manner. The response of the internal anal sphincter was not affected by l-NAME, indomethacin, and the K(+) channel blockers. CONCLUSIONS: This relaxant effect of adrenomedullin might lead to novel clinical applications of adrenomedullin for anorectal disorders with increased internal anal sphincter tonus, such as anal fissure.

Adrenomedullin↗

PubMed2003

Relaxant effect of omeprazole and lansoprazole in guinea pig gallbladder muscle strips in vitro.

BACKGROUND: The aim of this study was to investigate the role of omeprazole and lansoprazole, H(+)-K(+) ATPase inhibitors, in gallbladder smooth muscle contractility in vitro. METHODS: Gallbladder muscle strips obtained from guinea pigs were mounted in an organ bath. The responses of both precontracted strips and strips under basal tension to omeprazole and lansoprazole were determined. RESULTS: Spontaneous contractile activity was blocked following omeprazole and lansoprazole administration. The agents also caused concentration-dependent relaxation in carbachol- and KCl-precontracted gallbladder muscle strips. Pretreatment with atropine (1 microM), N(W)-nitro L-arginine methyl ester (L-NAME; 30 microM), indomethacin (10 microM), ammonium chloride (7.5 mM), sodium acetate (7.5 mM), tetraethylammonium chloride (0.5 mM), glibenclamide (1 micro M), 4-aminopyridine (0.1 mM), or clotrimazole did not inhibit this relaxation. Gallbladder strips were placed in high-concentrtion potassium (80 mM), calcium-free solution. The contraction produced with the addition of Ca(2+) (2.5 mM) was completely relaxed by omeprazole, lansoprazole, and nifedipine separately. CONCLUSIONS: These results demonstrate that omeprazole and lansoprazole have potent inhibitory effects on spontaneous contractions and cause dose-dependent relaxation in precontracted gallbladder smooth muscle strips of guinea pig in vitro. This effect could be due to blockade of the calcium channels.

2-Pyridinylmethylsulfinylbenzimidazoles↗

PubMed2003

Thyroid hormone supplementation in sepsis: an experimental study.

PURPOSE: The levels of thyroid hormones decrease in septic, critically ill, and major trauma patients who show a bad prognosis. The aim of this study was to investigate the effects of thyroid hormone supplementation on the sepsis criteria and mortality in an experimental sepsis model. METHODS: Forty-eight Wistar-Albino rats were divided into four experimental groups. A cecum ligation and puncture was used as a sepsis model. Group I: sham; group II: a cecum ligation and puncture (control); group III: a cecum ligation and puncture +T3 (0.4 microg/100 g body weight/day) intraperitoneally; group IV: a cecum ligation and puncture +T4 (1 500 ng/100 g body weight/day) intramuscularly. The PCO(2), leukocyte count, peritoneal bacterial content, neutropenia, and mortality rates were assessed in all groups. RESULTS: The PCO(2) levels decreased only in the control group ( P < 0.05). The leukocyte counts were lower in the therapy groups ( P < 0.05). The rate of neutropenia was seen much more in the control group ( P < 0.05). The peritoneal bacteria content decreased in the therapy groups ( P < 0.05). The mortality rate significantly decreased in the thyroid hormone-treated animals ( P < 0.05). CONCLUSIONS: Thyroid hormone supplementation in septic rats had a beneficial effect on the sepsis criteria and also resulted in a lower rate of mortality.

Animals↗

PubMed2003

Sigmoid colon perforation as an unusual complication of Behçet's syndrome: report of a case.

A 47-year-old man with long-standing Behçet's syndrome presented with an acute abdomen, and was found to have perforation of the sigmoid colon. Laparotomy revealed gangrenous changes in the sigmoid colon and perforation in the center of the affected segment. This is a very rare complication of Behçet's disease, and we report this case to stress the importance of performing careful abdominal examination while evaluating patients with Behçet's disease.

Behcet Syndrome↗

PubMed2003

Comparison of different thyroidectomy techniques for benign thyroid disease.

Extent of thyroidectomy in the management of benign thyroid disease remains controversial. In this clinical study, three different thyroidectomy techniques were compared by means of the complication, short period recurrence and L-thyroxin requirement rates. Two hundred consecutive patients who had bilateral subtotal thyroidectomy (BST) (n = 71), unilateral total lobectomy + contralateral subtotal lobectomy (Dunhill Procedure (DP)) (n = 71), or total thyroidectomy (TT) (n = 58) for benign thyroid disorders were included in this study. One patient was re-operated due to bleeding in BST group. Wound infection was observed in 1 patient both in BST and DP group and 2 patients in TT group. Temporary hypocalcaemia was seen in 14 (19.7%) of BST group, in 19 (26.7%) of DP group, and in 14 (24.1%) patients of TT group (p>0.05). Transient recurrent laryngeal nerve palsy developed in 1 patient both in DP and TT group. One patient of DP group had secondary thyroidectomy due to postoperative diagnosis of papillary carcinoma. There was no significant difference in the mean durations of hospitalization between the groups. Mean postoperative follow-up periods were 27.7 months (6-56), 34.8 months (8-55), 26.5 months (6-54) in BST, DP and TT groups, respectively. While all patients were administered L-thyroxin in TT group, 26 (36.6%) patients in DP group and 34 (47.8%) patients in BST group needed no L-thyroxin supplementation and L-thyroxin requirement rates were not different in either group. We think that total thyroidectomy should be adopted for benign thyroidal diseases, because its complications are no different than those for BST and DP. If individual factors and patient's preference are not in favor of lifelong L-thyroxin supplementation, however, DP may be carried out for benign thyroidal diseases instead of BST.

Adolescent↗

PubMed2003

Traumatic pelvic hydatid cyst rupture: report of a case.

Secondary peritoneal echinococcosis is one of the important complications of cyst hydatid disease. Although many ruptured hydatid cysts of a primary organ have been reported, there is only one case of peritoneal hydatid cyst rupture in the literature. In this case report we present a 25 year-old male patient, who had been operated for hydatid cyst of the liver four years ago and had pelvic hydatid cyst rupture due to blunt abdominal trauma.

Abdominal Injuries↗

PubMed2002

A simplified operative technique for single-staged resection of left-sided colon obstructions: report of a 9-year experience.

PURPOSE: The operative strategy for left-sided large bowel obstruction remains controversial. Because a safe and definitive single-staged operation that avoided a colostomy would clearly be in the patients' best interest, we conducted a prospective study to compare the efficacy of single-staged surgery (SSS) supplemented by the milking and swabbing technique (MST), with the conventional Hartmann's procedure (HP). METHODS: In group 1 ( n = 37) we performed traditional HP by resecting the site of obstruction and constructing an end colostomy. In group 2 ( n = 33), after resecting the site of obstruction, instead of on-table lavage, we cleaned out the fecal content from the proximal and distal parts of the obstruction by milking the colon with the fingers, then swabbing the proximal and distal 10 cm of lumen of the colonic anastomosis with povidone iodinized stick sponges. Finally, we performed a primary one-layer anastomosis without fecal diversion. RESULTS: The mortality, morbidity, and postoperative hospital stay after emergency left-side colonic resection and primary anastomosis by MST was comparable with those after HP ( P > 0.05). CONCLUSIONS: We believe that SSS with MST is a viable choice in the surgical management of selected patients with obstructing lesions of the left colon. The advantages of SSS with MST lie in its good long-term results, and short-term reduced surgical intervention and hospital stay.

Acute Disease↗

PubMed2002

Effect of thyroid hormones on stress ulcer formation.

BACKGROUND: Stress ulcers are gastric mucosal lesions that may cause life-threatening upper gastrointestinal bleeding. Although it is known that hyperthyroid status prevents stress ulcer formation, the effect of thyroid hormones given just as the stress is beginning has not been studied. The aim of this study was to assess the effect of thyroid hormone supplementation on gastric stress ulcers at the beginning of the restraint stress. METHODS: Thyroid hormones were administered to rats 2 days before or at the beginning of the restraint stress. The linear length of the gastric mucosal lesions, mucosal pH and thyroid hormone levels were measured and histopathological examinations were carried out. RESULTS: It was found that both triiodothyronin and thyroxin reduce the length and depth of the stress ulcers (P < 0.001). CONCLUSION: Although the mechanisms by which the thyroid hormones act on stress ulcers are uncertain, current experimental studies suggest that thyroid hormones reduce the formation of stress ulcers in rats when given before or at the beginning of the stress.

Animals↗

PubMed2002

Pancreatic pseudotumor due to peripancreatic tuberculous lymphadenitis.

Peripancreatic tuberculous lymphadenitis is a very rare and difficult diagnosis. We report herein a patient with a clinically solitary abdominal tuberculoma. A 68-year-old woman was admitted to our hospital with moderate-level obstructive jaundice due to a mass located between pylorus and head of the pancreas. There were no clinical signs or symptoms of tuberculosis in lungs or abdomen. After the diagnosis of a neoplasm of the pancreas was made, exploratory laparotomy was performed which revealed a conglomerated mass penetrating into the pancreas. Since an exact diagnosis could not be reached on the basis of frozen sections prepared during the operation, a standard Whipple procedure was performed. After the histopathological examination of the resected specimen revealed tuberculous lympadenitis, the patient was given antituberculous medication. The patient recovered well. An abdominal tuberculoma is often mistaken for a malignant neoplasm, and nonsurgical diagnosis and treatment of this entity continues to be a challenge.

Aged↗

PubMedDate not supplied

Surgical management strategies in patients with primary hyperparathyroidism: which technique in which patients?

OBJECTIVE: This study was planned to investigate the efficacy of either 99mTc-sestamibi scan or ultrasonography in predicting the operative treatment in patients with primary hyperparathyroidism (PHPT). SUBJECTS AND METHOD: Thirty patients (25 female, 5 male; mean age: 53 years) being operated for symptomatic primary PHPT were included in this study. Ultrasonography was used in 29 patients while 99mTc-sestamibi scintigraphy was done in 28 patients to localize the hyperfunctioning gland(s). Standard bilateral neck exploration was done in 6 patients. Although unilateral intervention had been planned for 24 patients, bilateral intervention was performed in 9 of them. RESULTS: Sensitivity of 99mTc-sestamibi was 81%, while that of ultrasonography was 42%. 99mTc-sestamibi localization method led to misleading results in 10/28 (35.7%) patients. False-positive localization and accompanying thyroid pathologies played an important role in determining transition from unilateral to bilateral intervention. CONCLUSION: Our findings indicate that bilateral intervention remains a successful management option without prior localization in patients with PHPT especially in an endemic goiter region.

Female↗

PubMedDate not supplied

Octreotide inhibits hepatic fibrosis, bile duct proliferation and bacterial translocation in obstructive jaundice.

BACKGROUND/AIMS: The protective effect of octreotide on bacterial translocation, bile duct epithelial proliferation and hepatic fibrosis was studied in an experimental obstructive jaundice model. METHODOLOGY: Forty-five healthy Wistar albino rats were randomly divided into three groups. Group I (n = 15): Median laparotomy and common bile duct manipulation performed (Sham group). Group II (n = 15): Laparotomy and common bile duct ligation performed. Group III (n = 15): After laparotomy and common bile duct ligation octreotide (Sandostatin, sandoz) was given. Simultaneously group I and II received 3 cc 0.9% NaCl and group III received 20 micrograms/kg/daily octreotide subcutaneously every 8 hours during 9 days. Two days after the procedure all rats were opened under ether anesthesia and sterile conditions. Group I had simple laparotomy but group II and III also had common bile duct ligation by 5/0 prolene. Seven days after the surgery (9th day after treatment) all rats underwent laparotomy and tests for bacterial translocation, liver biochemical tests and histopathologic analysis of liver and small bowel were carried out. RESULTS: In group II cecal population levels of bacteria were significantly higher than group I and group III (p < 0.05). In group II there was also statistically significant bacterial translocation to the mesenteric lymph nodes. Pathological changes were found in terminal ileum samples in group II which seemed to improve in group III. Hepatocyte function was preserved with octreotide treatment which also significantly decreased bile duct proliferation and periportal fibrosis in response to biliary obstruction. CONCLUSIONS: This experimental study showed that octreotide is effective in preventing bacterial translocation, bile duct proliferation and hepatic fibrosis in obstructive jaundice.

Animals↗