Biomedical subjects

Melih Tugay

Publications and source records attributed to Melih Tugay.

15 recordsLinked to original sources

PubMed2006

Colitis cystica profunda: MRI appearance.

Colitis cystica profunda (CCP) is an uncommon benign condition characterized by mucin-filled cysts located in the submucosa, frequently associated with the solitary ulcer and rectal prolapse syndromes. The diagnosis of this entity is important as it can mimic rectal cancer and therefore may result in unnecessary surgical resection. Endoscopic examination and barium enema findings are suggestive but not specific, neither are superficial biopsy findings. Transrectal ultrasound is helpful in the diagnosis by imaging the layers of the rectal wall. The authors report a 16-year-old male with a rectal lesion mimicking malignant mass on endoscopic examination. The lesion was defined as CCP, based on MR imaging findings which disclosed multiple noninfiltrating submucosal cysts, confirmed by histopathological examination. To our knowledge, this is the first case of CCP in the radiology literature describing MRI findings.

Adolescent↗

PubMed2006

Effects of erdosteine on bleomycin-induced lung fibrosis in rats.

This study was designed to examine the effects of erdosteine on bleomycin (BLM)-induced lung fibrosis in rats. Thirty-three Sprague-Dawley rats were divided randomly into three groups, bleomycin alone (BLM), bleomycin + erdosteine (BLM + ERD), and saline alone (control). The BLM and BLM + ERD groups, were given 2.5 mg/kg BLM intratracheally. The first dose of oral erdosteine (10 mg/kg/day) in the BLM + ERD group was started 2 days before BLM administration and continued until animals were sacrificed. Animals were sacrificed 14 days after intratracheal instillation of BLM. The effect of erdosteine on pulmonary fibrosis was studied by analysis of bronchoalveolar lavage (BAL) fluid, histopathology, and biochemical measurements of lung tissue superoxide dismutase (SOD) and glutathione (GSH) as antioxidants, malondialdehyde (MDA) as an index for lipid peroxidation, and nitrite/nitrate levels. Bleomycin-induced lung fibrosis as determined by lung histology was prevented with erdosteine (grades of fibrosis were 4.9, 2.3, and 0.2 in BLM, BLM + ERD, and control groups, respectively). Erdosteine also prevented bleomycin-induced increase in MDA (MDA levels were 0.50 +/- 0.15, 0.11 +/- 0.02, and 0.087+/- 0.03 nmol/mg protein in BLM, BLM + ERD, and control groups, respectively) and nitrite/nitrate (nitrite/nitrate levels were 0.92 +/- 0.06, 0.60 +/- 0.09, and 0.56+/- 0.1 micromol/mg protein in BLM, BLM + ERD, and control groups respectively) levels. Bleomycin-induced decrease in GSH and SOD levels in the lung tissue also prevented by erdosteine [(GSH levels were 213.5 +/- 12.4, 253.2+/- 25.2, and 287.9+/- 34.4 nmol/mg protein) (SOD levels were 1.42+/- 0.12, 1.75+/- 0.17, and 1.89+/- 0.09 U/mg protein) in BLM, BLM + ERD, and control groups respectively]. Erdosteine prevented bleomycin-induced increases in total cell number and neutrophil content of the BAL fluid. In conclusion, oral erdosteine is effective in prevention of BLM-induced lung fibrosis in rats possibly via the repression of neutrophil accumulation, inhibition of lipid peroxidation, and maintenance of antioxidant and free radical scavenger properties.

Acute Lung Injury↗

PubMed2006

Totally implantable central venous access devices in children with hemato-oncologic malignancies: evaluation of complications and comparison of incidence of febrile episodes with similar patients without central venous access devices.

The incidence of mechanical and infectious complications of totally implantable central venous access devices (TIDs) must be related to underlying disease, intensity of the chemotherapy, and frequency of manipulations. Records of the patients hospitalized from January 2002 to May 2005 were evaluated. Patients with TIDs were matched with patients without TIDs having the same malignancy and the same anti-neoplastic chemotherapy. Catheter-related complications were documented and corresponding phases of the chemotherapy in matched pairs were compared with regard to infections. TIDs were inserted in 31 patients with a median age of 4.3 years (22 acute leukemia, 1 NHL, and 8 solid tumors). Total number of catheter days was 5268, with a median catheter life of 174 days (range 9-493 days). Nine catheters (29%) were removed due to mechanical and infectious complications. There was 13 catheter-related infections with a rate of 2.46/1000 catheter days. Total number of mechanical complications was 5 and overall rate of complications was 3.41/1000 catheter days. The rate of febrile episodes was 54 and 41 in the TID and no TID group, respectively (p: .11). Duration of neutropenia was 9.6 and 7.4 days and duration of fever per febrile attack was 5.6 and 4.4 days in the TID and no TID group, respectively (p: .047 and .56). Although most of the patients in this study had hematological malignancy and required frequent manipulation, the results were similar to those in developed countries. TIDs are essential for management of chemotherapy in pediatric malignancies with acceptable complications.

Antineoplastic Agents↗

PubMed2006

Unresectable multifocal hepatoblastoma with cardiac extension: excellent response with HB-94 chemotherapy protocol.

A 10-month-old white infant presented with abdominal distention and bilateral scrotal hernia. Imaging studies of the abdomen and thorax showed a huge liver with multiple tumor masses and calcification involving all the segments. There was thrombosis in the inferior vena cava and right atrium. alpha-Fetoprotein was 246,000 IU/mL. HB-94 chemotherapy protocol was started at once due to rapid deterioration of the patient. Surgical biopsy performed after the first IPA (ifosfamide, cisplatin, doxorubicin) course showed hepatoblastoma with macrotrabecular variant. After a second IPA course and 2 courses of carboplatin and etoposide, the boy's clinical condition was excellent with normal alpha-fetoprotein but minimal regression and increased calcification in the tumor mass. Hepatic tumor was unresectable and no surgical intervention was performed. Transplantation could not be performed because of high morbidity and mortality. Despite general agreement that complete surgical resection is the cornerstone of treatment for patients with hepatoblastoma, the patient is in remission with 100% Karnofsky score in the 43 months of diagnosis.

Antineoplastic Agents↗

PubMed2005

Effects of vitamins E, A and D on MDA, GSH, NO levels and SOD activities in 5/6 nephrectomized rats.

BACKGROUND: Excessive generation of reactive oxygen species (ROS) contributes to the process of progressive renal injury in a variety of clinical and experimental renal diseases. The present study was designed to test the hypothesis that treatment with vitamins decreases renal injury in chronic renal failure (CRF). METHODS: Forty male Sprague-Dawley rats were divided into 5 groups: group 1, control; group 2, 5/6 nephrectomy (CRF); other groups 5/6 nephrectomy and injected vitamins (E, A, D). After 8 weeks, urea, creatinine and renal tissue malondialdehyde (MDA), glutathione (GSH), nitric oxide (NO) levels and superoxide dismutase (SOD) activities were determined. RESULTS: Renal tissue MDA levels were significantly lower in the control and Vit E groups compared to that of the CRF, Vit A and Vit D groups. GSH levels were significantly higher in the control group compared to that of other groups. However, GSH levels were significantly lower in the control group than those in the other groups. SOD activities of the control group were significantly higher than those in the other groups. SOD activities were significantly decreased in the Vit E group compared to the Vit A and Vit D groups. Tissue NO levels of control group were significantly increased compared to the other groups. CONCLUSION: According to this study, Vit E may at least in part prevent tissue injury by acting as a free radical scavenger.

Animals↗

PubMed2005

Testicular biopsy during orchidopexy procedure: does it have an adverse effect on fertility?

INTRODUCTION: The aim of this study is to evaluate the effect of the gonadal biopsy procedure on fertility and histology of the experimentally created undescended testis. MATERIALS AND METHODS: Thirty Wistar-Albino rat litters were divided into three groups. In the first two groups, undescended testes were obtained by dividing the right gubernaculum in the first 48 h and the third group constituted the sham group. When the rats were 30 days old, orchidopexy was performed in the first group (O), whereas orchidopexy and testicular biopsy were performed in the second group (OB). After the fertility study all rats were sacrificed at week 11 and testicular weights, mean seminiferous tubular diameters (MSTD) and mean testicular biopsy scores (MTBS) were measured. RESULTS: One testis in the O group and three testes in the OB group were atrophied and these rats were excluded from the study. Testicular weights, MSTD and MTBS values of the operated side in the O and OB groups were lower than those in the sham group. There was a statistically significant difference between the MSTD values of the ipsilateral testes in the OB group and sham group (p<0.05). MTBS values of the ipsilateral testes in the O and OB groups were <8. There was no difference in all parameters in the contralateral testes between all groups (p>0.05). All the evaluated rats were fertile. While there was no difference in number of fetuses and fertility scores between the O and OB group, however, the differences were significant between each of these groups and the sham group (p<0.05). CONCLUSION: Testicular biopsy in the unilateral undescended testis model results in limited histological changes without affecting the fertility.

Aging↗

PubMed2004

Foregut smooth muscle reactivity changes in the hydrocephalus-induced infantile rats.

BACKGROUND: An association between hydrocephalus and gastroesophageal motor abnormalities that cause gastroesophageal reflux (GER) is well known. Our aim was to investigate hydrocephalus-induced alterations in esophageal and gastric smooth muscle reactivity and their modulation by pharmacological interventions in the rat model. MATERIALS AND METHODS: Hydrocephalus was induced in infantile rats by injection of kaolin into the cisterna magna. Hydrocephalic and sham-operated rats were exsanguinated 2 weeks after surgery. Esophageal and gastric fundus smooth muscle strips were studied in vitro for their contractile and relaxant response to receptor activation in the organ chambers set up. Additionally, esophageal and gastric tissue specimens were examined histologically for GER-induced changes. RESULTS: No histological evidence of esophageal and gastric changes reflecting GER was observed in the specimens of the control and hydrocephalus-induced rats. Maximum contractile responses of esophageal and gastric fundus smooth muscle to KCl and muscarinic receptor agonist carbachol were increased in the hydrocephalic groups compared with the control groups. These changes were statistically significant. Relaxant responses to beta adrenoceptor agonist isoprenaline were similar in the esophageal muscle strips of both hydrocephalic groups and the control groups. However, isoprenaline-induced relaxant responses of the gastric fundus muscle strips in the hydrocephalus-induced groups were significantly decreased as compared with the control groups. The relaxant responses to papaverine in the esophageal and gastric fundus smooth muscle strips were similar in the two groups. CONCLUSIONS: Our study revealed alterations of receptor-dependent and receptor-independent foregut smooth muscle reactivity in the hydrocephalus-induced rat pups. Therefore, we suggest that impaired smooth muscle reactivity at least in part may contribute to abnormalities of foregut motor function seen in patients with hydrocephalus.

Age Factors↗

PubMed2003

Expression of cell adhesion molecules in the adriamycin-induced esophageal atresia rat model.

Cell adhesion molecules are well-known membrane glycoproteins widely expressed during embryonic development that play a crucial role in cell division, migration and differentiation. We investigated the cell-matrix relationship using N-CAM and pan-cadherin adhesion molecules in the adriamycin-induced esophageal atresia (EA) rat model in the hope of finding a clue to the mechanisms of this unique anomaly.Time-mated pregnant Sprague-Dawley rats were given either saline or adriamycin on days 8 and 9 of gestation. Embryos were harvested on the 18th day of gestation. Esophageal specimens obtained from adriamycin-exposed embryos with (EA+) or without esophageal atresia (EA-) and from saline-exposed embryos were immunostained with N-CAM and pan-cadherin primary antisera. The esophageal specimens from control and EA- groups revealed similar immunostaining properties: weak N-CAM and pan-cadherin immunoreactivity. In contrast, the EA+ group showed intense immunoreactivity. Our study demonstrated an increased synthesis of N-CAM and pan-cadherin in the epithelial cells of the atretic esophagus and trachea. These results suggest that embryonic cell-cell and cell-matrix interactions may play a crucial role in the development of adriamycin-induced EA.

Animals↗

PubMed2003

Gastric smooth muscle contractility changes in the esophageal atresia rat model: an in vitro study.

PURPOSE: The aim of the study was to investigate the gastric smooth muscle reactivity in the Adriamycin-induced esophageal atresia (EA) rat model. METHODS: The fetuses were divided into 3 groups. The control group was exposed to saline. The second group was comprised of fetuses that were exposed to Adriamycin but did not have EA (Adriamycin-no-EA group). The third group was comprised of fetuses that were exposed to Adriamycin and had EA (Adriamycin-EA group). Gastric fundus strips were studied in vitro for their contractile response to receptor activation in the 3 groups. RESULTS: Contractile responses of gastric smooth muscle to carbachol and KCl were increased in the Adriamycin-EA group compared with the Adriamycin-no-EA group. Also serotonin-induced contractile response in the Adriamycin-EA group decreased compared with the Adriamycin-no-EA group. Relaxation of gastric smooth muscle strips to isoproterenol was comparably unaffected in the Adriamycin-EA and Adriamycin-no-EA groups. Likewise, no change in the response to agonist studies was observed between the control and Adriamycin-no-EA groups. The relaxant response to papaverine was not different in the 3 groups. CONCLUSIONS: This study found changes of receptor-dependent and receptor-independent contraction of the gastric fundus smooth muscle in the fetuses with EA. Therefore, impaired contractile responses may be, at least in part, a contributing factor in the abnormal gastric motility seen in EA.

Animals↗

PubMed2003

Effects of caustic lye injury to the esophageal smooth muscle reactivity: in vitro study.

PURPOSE: We investigated late effects of caustic lye injury on esophageal smooth muscle reactivity in the rat model. MATERIALS AND METHODS: Male Sprague-Dawley rats were divided into two groups. Through a median laparatomy incision, abdominal esophageal segment was isolated. Orogastric and gastric (via gastrotomy) catheters were placed and tied over the isolated esophageal segment. Saline (0.9%) or 50% sodium hydroxide (1 ml) solution were instilled via orogastric catheter to the isolated segment in the control and caustic esophagus (CE group) groups, respectively. Then, the esophagus was rinsed with 0.9% saline via gastric catheter. The esophagus was removed and studied in organ chambers 28 days after the operation. RESULTS: Carbachol- and KCl-induced contractile responses of esophageal smooth muscle were significantly reduced in the CE group with decreased E(max) value compared with the control group. Relaxant responses to serotonin were significantly reduced in the CE group with decreased E(max) value compared with the control group. No significant differences were found in E(max) and pD(2) values for papaverine acting on esophageal strips from the two groups. CONCLUSION: The results provide evidence that, a surgically created caustic injury causes impaired smooth muscle reactivity that may contribute to esophageal motor dysfunction.

Animals↗

PubMed2003

Impaired gastric motility in the gastroesophageal reflux rat model: an in vitro study.

PURPOSE: The present study investigated the effects of acid and mixed reflux on the responsiveness of gastric smooth muscle in the gastroesophageal reflux (GER) rat model. MATERIAL AND METHODS: Three groups of rat were studied encompassing acid reflux, mixed reflux and sham operation. Acid reflux was induced by pyloric ligation (AR group) and mixed reflux was induced by jejunal ligation 1 cm distal to Treitz ligament (MR group). Similar surgical manipulations were carried out in the sham operated rats (SO group). Carbachol-, serotonin-, KCl-induced contractile response and nicotine-, sodium nitroprusside-, papaverine-induced relaxant response in isolated gastric fundus smooth muscle strips were determined using in vitro muscle technique 24 h after surgery. RESULTS: Isolated gastric fundus smooth muscle contractility to serotonin, carbachol or KCl was significantly reduced in the AR and MR groups with decreased Emax and pD(2) values compared with the SO group. Relaxant responses to nicotine was significantly increased in the AR and MR groups with increased Emax and pD(2) values compared with the SO group. Sodium nitroprusside and papaverine-induced-relaxant responses were similar in all of the groups and there was no change in agonist potency. CONCLUSION: The present study indicates that decreased contractile and increased nicotine-induced relaxant response of the gastric smooth muscle in the surgically created GER model. These findings suggest that impaired gastric smooth muscle reactivity at least in part may play a role in gastric dysmotility in GER.

Animals↗

PubMed2003

Age-related smooth muscle reactivity changes in the rat bladder: an in vitro study.

An experimental study was conducted to investigate developmental changes of the rat detrusor smooth muscle (DSM) reactivity from newborn to adult period. Urinary bladders were obtained from adult (4 months old), 1-month-old and newborn (4-7 days old) male Sprague-Dawley rats. DSM reactivity of the three groups was evaluated in organ chambers. The newborn DSM strips revealed markedly increased purinoceptor- and cholinoceptor-mediated contractions (ATP, carbachol) with increased maximum response (2.98- and 8.96-fold increase for ATP, 2.90- and 4.22-fold increase for carbachol, when the newborn bladder compared with 1-month-old and adult groups, respectively) and sensitivity (1.65- and 1.29-fold increase for ATP when the newborn bladder compared with the 1-month-old and adult groups, respectively). Additionally the maximum contractile response to KCl in the bladder from the newborn was 1.65- and 8.96-fold increased compared to bladders of the 1-month-old and adult groups, respectively. However, no significant changes in the adrenoceptor-mediated relaxation (isoproterenol) of the rat DSM were observed among the groups. These results indicate that development alters the in vitro responsiveness of rat DSM. The newborn rat bladder gains some of the adult bladder properties within 1 month. These changes are likely to reflect the changing role of parasympathetic regulation in the DSM reactivity during development of the rat bladder.

Adenosine Triphosphate↗

PubMed2003

Development changes esophageal smooth muscle reactivity: an in vitro study.

This study was designed to determine if age related changes occur in esophageal smooth muscle reactivity in developing rats. Esophageal smooth muscle strips were obtained from three groups of rats: neonatal (1-3 days old), 1-month-old (30-35 days old) and young adults (4 months old). Esophageal smooth muscle reactivity was assessed in vitro by organ chamber experiments. Concentration-response curves were analyzed for differences in smooth muscle reactivity. Contractile response to cholinergic agonist carbachol increased in the neonatal group with increased maximum contraction compared to the other groups. However, there was no change in pD(2) value among the groups. Maximum contraction evoked by KCl was also significantly increased in the neonatal group compared to the adult group. Relaxation responses elicited by beta adrenoceptor agonist isoproterenol and 5-hydroxytryptamine (5-HT) receptor agonist serotonin were increased in the neonatal group with increased E(max) and pD(2) values compared to the other groups. The present study indicates that the neonatal esophageal smooth muscle responds to serotonergic, adrenergic and cholinergic agonists to a significantly greater degree than the adult esophageal smooth muscle.

Adrenergic beta-Agonists↗

PubMed2003

Esophagitis impairs esophageal smooth muscle reactivity in the rat model: an in vitro study.

The present study investigated how reflux-induced esophagitis affects the smooth muscle reactivity of the esophageal body. Two different esophagitis models were used: acid gastric and mixed duodenogastric reflux. All test animals apart from the controls developed gross and histologic evidence of esophagitis. Contractile (carbachol and KCI) and relaxant (isoproterenol) esophageal smooth muscle responses were significantly decreased in the presence of acid- and mixed reflux-induced esophagitis. Similar relaxant responses to serotonin and papaverine were found in the three groups. Our study demonstrated impaired esophageal smooth muscle reactivity when esophagitis was induced by acid or mixed reflux. These changes may correspond to the functional motor abnormalities of the esophagus seen in patients with reflux esophagitis.

Animals↗

PubMed2003

Laparoscopic evaluation in incarcerated groin hernia following spontaneous reduction.

The authors report their initial experience of diagnostic laparoscopy in a baby presenting with small bowel obstruction secondary to strangulated groin hernia. Laparoscopy was accomplished through ipsilateral hernia sac to determine the viability of the incarcerated bowel segment under general anesthesia, following spontaneous reduction under general anesthesia. Diagnostic laparoscopy showed edematous intestinal segments but no sign of necrotic bowel or indirect findings of intestinal perforation. Diagnostic laparotomies may be useful in selected cases preventing an unnecessary laparotomies.

Diagnosis, Differential↗