Biomedical subjects

S Yücesan

Publications and source records attributed to S Yücesan.

At least 19 recordsLinked to original sources

PubMed2002

Polyunsaturated phosphatidylcholine lowers collagen deposition in a rat model of corrosive esophageal burn.

Esophageal strictures are characterized by excess deposition of collagen in the esophageal wall. Polyunsaturated phosphatidyl-choline (PPC) stimulates collagen breakdown in experimental models of liver cirrhosis and colitis. This study was done in order to investigate the therapeutical effect of PPC in preventing esophageal strictures due to alkali-induced esophageal burns in rats. Fifty-five albino rats were divided into four groups as follows: control group (Group A, 10 rats), rats with sham operation and treated with saline (Group B, 15 rats), rats with esophageal burns only (Group C, 15 rats), and PPC-fed rats with esophageal burns (Group D, 15 rats). A standard esophageal burn was produced as described by Gehanno. PPC was administered orally to Group D rats in doses of 100 mg/day for four weeks. All animals were sacrificed on the 28th day of the experiment. Hydroxyproline levels in esophageal tissue was determined in each rat, and histopathologic evaluation was performed for each group. Hydroxyproline levels were significantly lower in the PPC-fed rats than in the rats with pure esophageal burns (p < 0.001). Histopathologically, collagen deposition in the submucosa and tunica muscularis was lower in Group D rats (PPC-fed rats with esophageal burn) than Group C rats (pure esophageal burn) (p < 0.05). As a result of our study, we concluded that PPC has an ameliorating effect on stricture formation after alkali-induced corrosive esophageal burns in rats.

Animals↗

PubMed2001

Outcomes of one-stage techniques for proximal hypospadias repair.

OBJECTIVES: To evaluate the success of three preputial flap techniques in the one-stage correction of proximal hypospadias. METHODS: From 1993 to 1999, 43 children underwent one-stage proximal hypospadias repair using preputial flaps, which were performed by a single surgeon. Of the 43 patients, 21 (48.8%), 10 (23.2%), and 12 (27.9%) underwent tubularized island flap urethroplasty, double-faced tubularized island flap urethroplasty, and onlay island flap urethroplasty, respectively. The age range of the patients at surgery was 18 months to 14 years (mean 3.4). Dorsal plication was required for chordee repair in 12 patients (3 in tubularized island flaps, 3 in double-faced tubularized island flaps, and 6 in onlay island flaps). In addition to the dorsal plication, posterior dissection of the urethral plate without division was performed on 3 of the 6 patients with mild to severe chordee in the onlay island flap group. The incidence of complications requiring repeated surgery was evaluated for each group. RESULTS: The follow-up was 8 months to 7 years (mean 4.1 years). The overall complication rate was 90% for the double-faced tubularized island flap repair, 38% for the tubularized island flap repair, and 33% for the onlay island flap repair. Recurrent chordee was observed in 2 (66.6%) of the 3 patients who underwent onlay island flap repair with urethral plate dissection. CONCLUSIONS: The use of a tubularized island flap is suggested for one-stage repair of proximal hypospadias, especially in the patients with severe chordee. Because of the high complication rates, the double-faced tubularized island flap technique is not advocated. The onlay island flap may also be used for proximal hypospadias repair if mild chordee is present. Because of the high recurrent chordee rate, dissection of the urethral plate without division is not suggested in the onlay island flap technique.

Adolescent↗

PubMed2001

The protective effects of captopril and nitric oxide on solitary kidney after chronic partial ureteric obstruction.

OBJECTIVE: To determine whether vasodilator agents (captopril and nitric oxide) change the morphological and functional effects of chronic partial ureteric obstruction in solitary kidney tissue in unilaterally nephrectomized rats. MATERIALS AND METHODS: Each of 50 prepubertal Wistar albino rats underwent right nephrectomy and were then assigned to one of five groups. Rats in group 1 underwent a sham operation (control) and in the other groups the ureter of the remaining kidney was partially obstructed by surgery. In group 2, no drug treatments were given; in groups 3, 4 and 5 captopril, L-arginine methyl ester (L-Arg) or NG- nitro-L-arginine-methyl ester, respectively, were given for 3 weeks. In all rats, diuretic scintigraphy was used to measure kidney perfusion, glomerular filtration rate (GFR) and concentration. Blood urea nitrogen (BUN), serum creatinine levels, kidney parenchymal weight and pelvic volume were measured and the kidneys evaluated histopathologically. RESULTS: Renal perfusion was significantly greater in both group 3 and 4 than in group 2. The GFR was 18% greater in group 3 and 22.3% greater in group 4 than in group 2. The GFR was decreased by 67% in group 5 compared with the control group. The mean parenchymal weight, mean pelvic volume, BUN and serum creatinine in the four groups with a partially obstructed ureter were significantly different from the control group. There also were significant differences between group 2 and groups 3--5, and between group 2 and group 3. Histological damage was severe in all four groups with partial ureteric obstruction, but in the drug-treated groups, medullary fibrosis was less frequent. CONCLUSION: After 3 weeks of treatment, captopril and L-Arg both improved kidney perfusion, GFR, BUN and serum creatinine levels, but were less effective in preventing parenchymal atrophy and changes in pelvic volume.

Angiotensin-Converting Enzyme Inhibitors↗

PubMed2000

Urogenital injuries in childhood: a strong association of bladder trauma to bowel injuries.

We analysed the inter-relationships of the cause and the type of trauma, the presence of pelvic fracture, the associated intraabdominal organ injuries, and the morbidity and mortality rates in 154 patients presenting and being treated for UGT between 1983 and 1997. The cause of injury was blunt in 77% of cases and penetrating in 13%. The most frequently injured organs were kidney followed by urethra and bladder. Bowels, liver and spleen were the most frequently associated injured organs. Moreover, bladder injuries were strongly associated with bowel injuries (p < 0.0001). Hemodynamically normal 49 children with minor or major kidney injuries were managed conservatively. Hemodynamically non-stable 11 patients were explored. The majority of urogenital injuries can be managed conservatively even when associated with intraabdominal organ injuries. Solid genitourinary organ injuries may accompany more frequently to intraperitoneal solid organ injury. Whereas, non-solid genitourinary organ injuries may more frequently associated with injuries of intraperitoneal hollow viscus.

Adolescent↗

PubMed2000

The protective effects of nitric oxide on the contralateral testis in prepubertal rats with unilateral testicular torsion.

OBJECTIVE: To investigate histological changes in the contralateral testis of rats with unilateral testicular torsion and the protective effects of nitric oxide (NO) on possible damage. MATERIAL AND METHODS: Twenty-eight prepubertal male Sprague-Dawley rats were divided into four equal groups. Group 1 underwent a sham operation of the right testis under general anaesthesia. Group 2 underwent a similar operation but the right testis was rotated 720 degrees clockwise for 6 h, maintained by fixing the testis to the scrotum, and saline infused during the procedure. Group 3 underwent similar torsion but L-arginine methyl ester (a precursor of NO) was infused during the procedure. In Group 4, NG-nitro-L-arginine-methyl ester, a NO synthase inhibitor, was infused separately during the administration of L-arginine methyl ester and torsion. All the left (untwisted) testes were removed from rats 21 days after surgery and evaluated histologically, assessing seminiferous tubule diameter, loss of sperm and spermatids, loss of germ cell layers, disarray of germ cell layers, rupture of tubules, Leydig cell proliferation and reaction in the ruptured tubules, and oedema. RESULTS: There was a significant difference in the indicators of histological damage between groups 2 and 4 and groups 1 and 3, except for the Leydig cell reaction in the ruptured tubules and oedema. The damage was significantly less in group 3 than in groups 2 and 4. CONCLUSION: These results suggest that long-term histopathological changes in the contralateral testes are important after unilateral testicular torsion and that NO has a protective effect on the contralateral testis.

Animals↗

PubMed2000

Internal inguinal hernia in a 20-month-old boy.

The authors report on a 20-month-old boy with internal inguinal hernia. The patient was reoperated for clinical signs of intestinal obstruction after an incarcerated inguinal hernia repair. The diagnosis of internal inguinal hernia was proven by surgical exploration. This is the first internal inguinal hernia case reported in the literature and completely different from the atypical parainguinal hernias reported before.

Hernia, Inguinal↗

PubMed2000

Colon injuries in children.

BACKGROUND/PURPOSE: Colonic injuries are rare in childhood, but when they do occur, they are mostly associated with penetrating abdominal injuries. The primary repair of colon injuries without stoma is still controversial within surgical experience, and the potential risk factors affecting morbidity and mortality is not sufficiently known. METHODS: Between 1985 and 1997, 34 children presenting with traumatic colonic perforations were reevaluated by analyzing the relationship between the overall morbidity and mortality and the potential risk factors. RESULTS: Of the 34 children in the case study, 27 boys and 7 girls, there were 7 (21%) isolated colonic injuries. The remaining 27 (79%) patients showed colonic injuries most frequently associated with the small bowel, the liver, and the bladder. Localization of injury was distributed thus: 21% in the right colon, 29% in the transverse colon, and 50% in the left colon. Primary repair, with or without intestinal resection, was performed in 27 (79%) of the patients. In total, postoperative complications occurred in 10 (29%) of the patients. Risk factors such as age, abdominal contamination, and associated abdominal organ injuries were found significant in these complications, however, the mechanism of injury, shock, blood transfusion, and localization of injury were not correlated significantly to postoperative complications. "'Flint's Colon Grading System" was used to ascertain the sensitivity of trauma scoring systems for postoperative complications. CONCLUSION: Colonic wounds can be repaired primarily without the need of colostomy in the majority of cases in children when the required selections are established.

Adolescent↗

PubMed1998

Ultrastructural and hormonal changes in the contralateral adrenal gland in unilateral adrenal gland ischemia: an experimental study in rats.

While it is well known that unilateral tissue ischemia may result in contralateral damage in some paired organs, there is no universally accepted mechanism to explain why these contralateral changes occur. The aim of the present study was to investigate the ultrastructural and hormonal changes that occur in the contralateral nonischemic adrenal gland after unilateral ischemia of an adrenal gland in a rat model. The animals were divided into four groups of four rats each; namely, a control group which received a sham operation without any ischemic insult, a 2-h ischemic group, a 4-h ischemic group, and an 8-h ischemic group. The left adrenal blood vessels were ligated in all ischemia groups and blood samples were taken for hormonal study 2, 4, and 8 h later, after which bilateral adrenalectomy was performed to determine the ultrastructural changes. The plasma concentrations of aldosterone and cortisol were determined by radioimmunoassays. There was an increase in both aldosterone and cortisol levels related to the duration of the ischemia, but the differences among the groups were not statistically significant. Contralateral ultrastructural damage such as heterochromatin in nuclei, mitochondrial degeneration, endoplasmic reticulum cisternal widening, increased lipid droplets, and lysosomes, were demonstrated electron-microscopically after unilateral adrenal ischemia.

Adrenal Glands↗

PubMed1997

Pentoxifylline inhibits overflow and reduces intestinal reperfusion injury.

The aim of this study was to determine the effects of pentoxifylline (Ptx) in reperfusion injury of the small bowel as a leukocyte stabilizer, free radical scavenger, and microcirculatory regulator. Ninety-six male Sprague-Dawley rats were used to determine the biochemical, histopathologic and blood flow changes of the reperfused small intestines after 30 minutes of a warm ischemic insult. Animals were divided into six groups: Sham (S), sham plus Ptx (SP), ischemia (I), ischemia plus Ptx (IP), reperfusion (R), and reperfusion plus Ptx (RP). Pentoxifylline was administered intraperitoneally at a dose of 50 mg/kg 15 minutes before ischemia. The superior mesenteric artery (SMA) was occluded distal to the right colic artery and collateral arcades were ligated as described by Megison. Sixty of the 96 rats (n = 10) were used to determine histopathologic changes, malondialdehyde (MDA), and myeloperoxidase (MPO) levels in tissue. Mucosal lesions were graded on a scale from 0 to 5 as described by Chiu. MDA and MPO levels of the intestinal mucosa were assayed to reflect the free radical formation and neutrophil sequestration, respectively. Thirty-six rats (n = 6) were used to measure blood flow changes of the intestine using 133Xe clearance technique. All data were presented as the mean values plus or minus the standard error of the means (means +/- sem). Although in the R group, mucosal injury score, blood flow, MPO, and MDA levels were higher significantly from the other groups (P < .05), in the RP group blood flow, MPO, and MDA levels were significantly decreased to the basal values (P < .05). Mucosal injury score of the RP group were lower than the reperfusion group but higher than the normal (P < .05). The authors conclude that pentoxifylline pretreatment before reperfusion stabilizes blood flow, decreases MPO and MDA levels to the normal, and attenuates but not completely prevents mucosal damage.

Animals↗

PubMed1996

Neonatal hypertrophic pyloric stenosis: congenital or infantile?

Hypertrophic pyloric stenosis (HPS) is very rare during the newborn period. Here we present a fullterm male neonate with abundant hematemesis 12 hours after birth which interrupted oral feeding. Bleeding subsided within three days after conservative measures, and oral feeding was restarted but not tolerated. The vomiting was effortless and nonbilious. An upper gastrointestinal series revealed gastric dilatation and partial obstruction of the gastric outlet. HPS was found by laparotomy on the fourth day and Fredet-Ramstedt pyloromyotomy relieved the gastric emptying. This is one of the few cases of HPS present at birth, which was diagnosed and surgically treated early, and we suggest a congenital etiology in previously reported cases of HPS. Hypertrophic pyloric stenosis (HPS) is a common cause of pediatric surgery. Usually young infants are involved; HPS is extremely rare in neonates and infants older than 6 months. Vomiting typically begins between the 3rd and 6th week of life, although some infants may have mild symptoms like regurgitation from birth.

Adult↗

PubMed1995

Distal penile hypospadias repair in children, with complete mobilization of pendulous urethra and triangular glandular flap.

OBJECTIVE: To present a technique for repair of distal hypospadias. PATIENTS AND METHODS: Sixteen children (average age 6.6 years) were treated between January 1985 and January 1991. The procedure is described. RESULTS: One child developed a mild meatal stenosis and another had a small urethral fistula; both responded to treatment. Results were excellent in the remaining 14 patients. CONCLUSION: This simple operative procedure was successful in the majority of patients and there were only two minor complications.

Anastomosis, Surgical↗

PubMed1994

A bronchopleurocutaneous fistula caused by an unusual foreign body aspiration simulating acute abdomen.

A 12-year-old boy was admitted to hospital for abdominal pain, vomiting and fever. On physical examination he had râles on the lower right hemithorax without any respiratory complaints. Chest X-ray revealed a condensation in the right lower chest. Abdominal findings were secondary to lobar pneumonia. Treatment of pneumonia with antibiotics showed no improvement over 2 days. On bronchoscopy no foreign body was seen, but pus was aspirated. Two days later a mass appeared on the right hemithorax and fistulized. An organic foreign body, Hordeum murinum, with 3-5 ml of pus was observed. Chest X-ray taken at the day of fistulization showed no pneumothorax or subcutaneous emphysema. Less than 11 cases of pneumocutaneous fistulas secondary to aspiration of grasses have been reported in literature. Why an ear of Hordeum murinum can migrate only in a forward direction and why a pneumothorax had not developed is discussed.

Abdomen, Acute↗

PubMed1994

Burkitt's lymphoma in Turkish children: clinical, viral [EBV] and molecular studies.

Eighty-one Turkish children with Burkitt's lymphoma (BL) were observed during a period of 24 years (1968-1992). The diagnosis was established histologically according to WHO criteria. BL represented 48.5% of NHL in this series. The median age of patients was 5 years with a sex (M/F) ratio of 2.3/1. The most common primary site of tumor involvement at initial presentation was the abdomen (70.4%), which was followed by facial tumors, in particular the jaw and orbit (45.7%). The majority of the patients (84.0%) were in advanced stages (C and D) at initial diagnosis. Facial tumors observed in Turkish children with BL were more similar to African Burkitt's lymphoma than American or European cases. High titers of antibodies against VCA and EA of EBV were also observed in 32 recent cases of BL. Preliminary molecular and immunologic studies revealed EBV-DNA (type I) and T cell deficiency. The clinical presentation, median age, and association with EBV revealed that BL appears to be inbetween African and non-African types in Turkish children. This will be further elucidated in the future by direct examination of tumor cells for EBV and investigation of the molecular characteristics in these cases.

Adolescent↗

PubMed1994

Blood flow determination in contralateral ovary with 133 Xe in unilateral ovarian torsion (experimental study in rabbits).

Clinical and experimental studies have shown that, in unilateral testicular torsion, some structural and hormonal changes may occur in the contralateral testis. The present study was designed to determine the effect of unilateral ovarian torsion on the blood flow in the contralateral ovary using #133Xe. Basal blood flow of the bilateral ovaries was determined in 40 prepubertal, female New Zealand rabbits. Right ovaries were then torsioned 720 degrees in all groups with the exception of the control group, where only laparotomy was performed. Bilateral ovarian blood flows were measured in the first group one hour after torsion, in the second group 8 hours after torsion, in the third group 24 hours after torsion and at the same times after laparotomy in the control group. Basal and post torsional blood flow measurements were analyzed. Contralateral ovarian blood flow was reduced after unilateral torsion in all of the groups. In the control group, there were no changes in these criteria.

Animals↗

PubMed1993

Burkitt's lymphoma between African and American types in Turkish children: clinical, viral (EBV), and molecular studies.

Seventy-two Turkish children with Burkitt's lymphoma (BL) observed during a period of 22 years (1968-1990) have been analysed retrospectively. The diagnosis was established histologically according to WHO criteria. BL represented 50% of NHL in this series. The patients were staged according to Ziegler's system. The median age of patients was 5.5 years with a sex (M/F) ratio of 2.1/1. The most common primary site of tumor involvement was the abdomen (69.4%), which was followed by facial tumors, in particular the jaw and orbit (49.9%). There were 21 cases with jaw (29.1%) and 15 cases with orbital involvement (20.8%) at initial presentation. The majority of the patients (84.4%) were in advanced stages (C and D) at initial diagnosis. Facial tumors observed in Turkish children with BL were more similar to African Burkitt's lymphoma than American or European cases. High titers of antibodies against VCA and EA of EBV were also seen in our recent cases of BL. Two main treatment regimens, namely, single agent chemotherapy with cyclophosphamide (CYX) (1968-1974) and three drug (COM) combination chemotherapy, were used consecutively (1974-1988). COM has been shown to produce better results than single agent therapy. The clinical presentation, mean age, and high antibodies (IgG) to EBV and preliminary molecular studies revealed that BL appears to be in between African and non-African types in Turkish children. This will be further elucidated by direct examination of tumor cells for EBV and investigation of the molecular characteristics of Turkish tumors. Such studies are presently under way.

Adolescent↗

PubMed1993

Prevalence of congenital abnormalities in Turkish school children.

19750 school children, ages 6 to 15 years, were examined by the authors of this study, 1,220 (6.18%) had congenital abnormalities. In this group, 4.23% were boys and 1.88% were girls. Case histories revealed inbreeding amongst the parents (families) of children with congenital malformation to be 8.9% and 8.2% for the rest of the families in this study. There were 27 different congenital abnormalities identified, with prevalence rates of 0.05/1,000 to 15.85/1,000. The most prevalent abnormalities were umbilical hernia (15.85/1000), inguinal hernia (14.50/1,000), pectus carinatum and excavatum (7.68/1,000), undescended testes (9.00/1,000 boys), congenital nevus (3.54/1,000), retractile testis (4.45/1,000 boys), pilonidal sinus (2.63/1,000), pes planus (2.28/1,000), and hemangioma (1.16/1,000). Of the 19,750 children, 70 had multiple anomalies (3.75/1,000).

Abnormalities, Multiple↗

PubMed1993

Histologic and ultrastructural changes in the contralateral ovary in unilateral ovarian torsion: an experimental study in rabbits.

This study was planned to investigate the extent of cellular damage of the contralateral ovary in unilateral ovarian torsion and to determine possible changes histopathologically by light and ultrastructurally by electron microscopy. Unilateral ovarian torsion was performed in 21 prepubertal, female New Zealand rabbits. One, 8 and 24 hours after the torsion, contralateral ovaries were biopsied. The control group consisted of rabbits without any torsion. Contralateral cellular damage was demonstrated after unilateral torsion. Oocytic nuclei, mitochondria, lysosomes and ovarian stromal cells were also affected when evaluated ultrastructurally.

Animals↗

PubMed1993

Augmentation of mucosal adaptation following small-bowel resection by electromagnetic field stimulation in rats.

Survival following massive resection of the small intestine is often possible due to substantial hyperplasia of the mucosal surface in the remaining small intestine. While nutrients provide the major stimulus for hyperplasia in the clinical setting, the availability of drugs to augment this process would have obvious therapeutic implications. Electromagnetic field stimulation (EMF) of connective tissue and skin increased the DNA and messenger RNA and protein synthesis in experimental studies. We evaluated the ability of electromagnetic field stimulation to augment mucosal hyperplasia following massive small bowel resection in the rat. Two groups of 10 Wistar rats, 250 gr body weight, were subjected to 70% jejunoileal resection. The first group received EMF stimulation for ten days at a dosage of 43.20 gauss, the second group did not receive any stimulation. After fourteen days, segmental evaluation of mucosal mass in the remaining small intestine was determined by measuring mucosal protein, and disaccharidase levels, as well as intestinal length and circumference. EMF stimulation appears to augment mucosal adaptation following massive small bowel resection in rat, in the proximal and distal small intestine.

Adaptation, Physiological↗