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Biomedical subjects

S Ercan

Publications and source records attributed to S Ercan.

At least 19 recordsLinked to original sources

Early mobilization after sliding and Z-lengthening of heel cord: a preliminary experimental study in rabbits.

Sliding lengthening and Z-lengthening techniques are widely used in heel cord lengthening. Even though most surgeons performing these procedures apply a short leg cast after surgery, their postoperative immobilization intervals vary from 3 to 7 weeks. Nather et al. showed that there was no need for immobilization after the musculotendinous lengthening of long, deep flexor tendons. In the present study, we aimed to show the healing process of heel cords lengthened by sliding and Z-plasty lengthening in rabbits that did not undergo any postoperative immobilization. We performed sliding lengthening in the right heel cords of the rabbits and Z-lengthening in the left heel cords. We compared these two techniques radiographically, biomechanically, and histopathologically. Even though the biomechanical study showed superior results in the sliding lengthening group on the 7th day, elongation of the tendons at both sites was seen radiographically. There was no statistically significant difference between the sites according to the biomechanical study done on the 28th day. We concluded that the ankle should be immobilized in the early healing phase and that both types of lengthening gain a similar level of strength by the 4th week.

Animals↗

Reservoir and globe-type antireflux surgical techniques in intrathoracic esophagogastrostomies.

Gastroesophageal reflux is a major postoperative problem in esophageal patients with cancer, and the principal cause is resection of the lower esophageal sphincter. Two new antireflux operations to solve this problem were investigated. The number of patients studied was 139, with a male to female ratio of 5. The reservoir technique was applied to the first 50 patients and the globe technique was used in the remaining 89. Hospital mortality was 9.35%. Patient satisfaction from a reflux standpoint was excellent in 91.4%, good to fair in 6.5%, and poor in 2.1%. Postoperative barium swallow at the first, third, and sixth months showed no reflux in 93% of cases. Postoperative preanastomotic mean pressure was 14.2 mmHg. Postoperative mucosal biopsies revealed a remarkable reduction in esophagitis. The radiologic, manometric, and histologic findings as well as the patient satisfaction rate suggest that these antireflux operations are suitable and effective for patients undergoing esophageal resection and intrathoracic esophagogastric anastomosis.

Esophageal Neoplasms↗

Acetabular dysplasia in normal Turkish adults.

The aim of this investigation was to examine normal hip joint morphometry and the acetabular dysplasia rate in Turkish adults. Center-edge angle, acetabular angle, acetabular depth, acetabular roof obliquity, and roof angle were measured in standardized pelvic radiographs of 495 adults without any hip symptoms. The center-edge angle was significantly different in the patients over the age of 70 than all other age groups except those in the 60 to 69 group. Additionally, there were differences between those in the 60 to 69 age group compared to those in the 20 to 29 age group. The acetabular angle showed a significant difference between gender and between the age groups over 60. The acetabular angle was negatively correlated with center-edge angle. Even though no significant differences were observed in the acetabular depth, differences in acetabular roof obliquity and roof angle were related to gender and age, all showed high standard deviations. The rate of acetabular dysplasia was 2.4% in the Turkish adult population aged 20 to 79. It is concluded that the center-edge angle may be a useful parameter in the evaluation of acetabular dysplasia if one is aware of its difference in patients over the age of 60.

Acetabulum↗

Ileal and colonic contractions by endothelin-1 in experimentally induced paralytic ileus in rats.

The aim of the present study was to investigate the effect of endothelin-1 on the isolated distal ileum and proximal colon in an experimentally induced ileus in rats. Ileal and colonic contractions by endothelin-1, acetylcholine alone and with endothelin-1 were recorded both in normal and experimentally induced paralytic ileus in rats. In the control group, all the responses to acetylcholine were found to be potentiated significantly when used together with endothelin-1 but in paralytic ileus group, no detectable change was observed in the responses of the amine after administration of acetylcholine together with endothelin-1. This study indicates that endothelin-1 might have an effect on gastrointestinal motility and postoperative paralytic ileus.

Acetylcholine↗

Comparison of omentum, pleura and diaphragm for tracheal autograft survival in rats.

Pleura, diaphragm, pericardial fat pad, intercostal muscles and omentum can be used to protect and revascularize the bronchial suture line. To compare the efficiency of pleura, diaphragm and omentum, an experimental study was designed. Heterotopic tracheal autotransplantation was performed in 15 rats. Animals were divided into three groups; omentum, diaphragm and pleura. Tracheal Segment Necrosis Scoring System was used for pathologic examinations. Pleural and diaphragmatic groups showed the least necrosis and there was significant statistical difference among these groups and omental group (P < 0.05). Our study showed that pleura and diaphragm could be used as safely as omentum for protection and survival of bronchial suture lines.

Analysis of Variance↗

Role of endogenous endothelin peptides in intestinal ischemia-reperfusion injury in rats.

In this study, the effects of BQ123 (an ET(A) receptor antagonist), bosentan (a nonselective ET(A)-ET(B) antagonist), and phosphoramidon (an endothelin converting enzyme inhibitor) were investigated on intestinal mucosal lesion formation and changes in tissue PGE2 and LTC4 levels due to intestinal ischemia-reperfusion (I/R) injury in rats. Following 30 min of ischemia, the substances were given via the inferior caval vein, and 10 min later the intestine was subjected to reperfusion for 30 min. The intestinal specimens were evaluated both microscopically and the tissue PGE2 and LTC4 levels were obtained for each group. The histopathologic examination revealed a significant reduction in tissue injury in both BQ123 and phosphoramidon pretreated groups compared with the control group. Bosentan, on the contrary, did not decrease the injury. The pharmacologic examination revealed a significant reduction of PGE2-like activity in both BQ123 and phosphoramidon pretreated groups, compared with the control group, while LTC4-like activity remained unchanged except for an increase in the bosentan pretreated group.

Animals↗

Correlation between sizes and intracystic pressures of hydatid cysts.

BACKGROUND: A bicentral prospective study was performed to assess the relationship between sizes and intracystic pressures (ICP) of pulmonary hydatid cysts as well as to compare these measurements in different age groups. METHODS: A total of 20 patients with 22 unperforated pulmonary hydatid cysts underwent surgery between April 1994 and September 1995. There were 12 males and 8 females with a mean age of 25.7 (7-62). Intraoperatively, ICP's were measured in cmH2O by direct cannulation. RESULTS: Out of a total of 22 cysts, 12 were located in the lower lobes. Mean diameter, volume and ICP of cysts were 9.6 cm (S.D. 4.2), 728.8 cm3 (S.D. 1014.9) and 36.6 cmH2O (S.D. 9.3), respectively. There was no significant correlation between various measurements of hydatid cysts, namely their short and long diameters, volumes and intracystic pressures (P > 0.05). There was no difference regarding the volume, ICP and age of patients, either among pulmonary lobes or between sexes. Patients who were 20 years old and less, presented a mean cystic diameter of 7.2 cm and mean ICP of 35.1 cmH2O, whereas the over 20 age group showed results of 11.9 cm and 38.1 cmH2O, respectively (P values were < 0.0083 for diameter and > 0.05 for ICP). CONCLUSIONS: Due to the small sample size and a few extreme measurements, the correlation between the sizes and the pressures of hydatid cysts turned out to be insignificant, but it is believed that a positive correlation is most probable with larger sample sizes. On the other hand, while the difference between the mean cystic diameters in age groups of below and over 20 was significant, the pressure difference between them was insignificant. This is why young patients carry the same risk of perforation as adults, although they present with relatively smaller cysts. Therefore, due to the well-known anaphylactic, obstructive and infectious risks of hydatid cyst perforation, urgent surgical removal is always necessary.

Adolescent↗

The effects of indomethacin, NDGA, allopurinol and superoxide dismutase on prostaglandin E2 and leukotriene C4 levels after mesenteric ischemia-reperfusion injury.

In this study, the changes of arachidonic acid metabolites after an ischemia-reperfusion (I/R) period are investigated. The cyclooxygenase and lipoxygenase metabolites were found to be significantly increased after a 45 min period of ischemia followed by 5 min of reperfusion. Prostaglandin E2 (PGE2)- and leukotriene C4 (LTC4)-like activities did not change in the ischemic period, but they both increased after reperfusion. A cyclooxygenase inhibitor indomethacin and lipoxygenase inhibitor nordehydroguaretic acid (NDGA) decreased PGE2- and LTC4-like activities, respectively, while allopurinol and superoxide dismutase (SOD) decreased both activities. According to our results, it can be assumed that free oxygen radicals are responsible for the elevation of PGE2- and LTC4-like activities and both of these arachidonic acid metabolites and free oxygen radicals are the main necrotizing agents in ischemia-reperfusion induced damage.

Alkaline Phosphatase↗

The principles of surgical management in dumbbell tumors.

OBJECTIVE: Tumors located in posterior mediastinum that extends into spinal canal via intervertebral foramen are called as Dumb-bell or Sand-glass tumors. Most of these tumors are neurogenic in origin but sometimes other rare tumors can also form in this shape. Herein three neurogenic tumors of the mediastinum that extended into the spinal canal are presented METHODS: In all patients that have been operated in our clinic during 1992-1993, we preferred one-stage removal described by Akwari that consists of posterior laminectomy by neurosurgical team to free the tumor within the spinal cord followed by a posterolateral thoracotomy and excision of the tumor by thoracic surgeons in the same setting. RESULTS: All three patients are alive and free of symptoms after 23, 16 and 13 months respectively. According to the pathological examinations of the specimens in the three patients, the exact diagnosis were reported as neurofibroma, paraganglioma and pheochromocytoma respectively. CONCLUSIONS: In recent reports, a combined surgical approach is recommended for dumb-bell neurogenic tumors in posterior mediastinum. We also recommend a combined and one stage removal of dumb-bell neurogenic tumors if possible. A team-work of thoracic and neurosurgeons will minimize the morbidity and mortality after the surgical procedure, as well as giving the opportunity to remove the tumor totally in one session.

Adolescent↗

Prophylactic administration of histamine 1 and/or histamine 2 receptor blockers in the prevention of heparin- and protamine-related haemodynamic effects.

The efficacy of prophylactic administration of H1 and H2 receptor blockers to prevent adverse haemodynamic responses to heparin and protamine was studied. The control group (n = 10) received no histamine receptor blocker, group H1 (n = 10) received oral terfenadine 60 mg, group H2 (n = 10) received oral ranitidine 300 mg, and group H1+H2 (n = 10) received both terfenadine and ranitidine on the night before the operation and on call to the operating room. Heparin sulphate 300 U/kg was injected directly into the right atrium, and protamine hydrochloride was administered at the conclusion of bypass over at least three minutes through a peripheral route. Following the injection of heparin, plasma histamine-like activity (H-LA) was increased significantly in all four groups. While systolic, diastolic, mean arterial and central venous pressures were decreased significantly in the control group, no significant changes were observed in the H1 and H2 groups. Protamine infusion did not lead to an increase in H-LA. Prophylactic administration of histamine receptor blockers (H1 or H2) attenuated the heparin-induced adverse haemodynamic response but did not change the protamine-related haemodynamic effects. Factors other than histamine may play a major role in protamine induced cardiovascular changes.

Administration, Oral↗

The role of prostanoids in the complications of extracorporeal shock wave lithotripsy (ESWL) in children.

ESWL is a safe and effective first-line treatment for urinary tract stone disease (UTSD) in children. The major complications arising from this procedure were upper urinary tract obstruction and ureteral colic. It was shown that prostaglandin synthetase inhibitors were effective in the treatment of urethral colic. The aim of this study was to measure urinary and plasma prostaglandin E2 (PGE2)- and leukotriene C4 (LTC4)-like activity in the patients who underwent ESWL before and after the treatment and investigate the role of cyclooxygenase (CO) and lipoxygenase (LO) products in early and late complications of ESWL. Urinary PGE2-like activity were increased 1 h after ESWL. (1.19 +/- 0.12 vs 1.59 +/- 0.15 g/ml, p < 0.02). The plasma values were decreased significantly after the treatment (16.7 +/- 1.7 vs 11.6 +/- 1.2 g/ml, p < 0.005). Urinary and plasma LTC4-like activities were found to be significantly decreased in the post-ESWL samples (0.58 +/- 0.006 vs 0.39 +/- 0.04, p < 0.002; 8.6 +/- 0.9 vs 4.2 +/- 0.6, p < 0.001, respectively). In conclusion, ESWL may stimulate the release of PG from the urinary tract resulting in increased peristaltism and the passage of stone fragments into the bladder. As this group of drugs has also nephrotoxic effects, they can be given prophylactically only to selected patients.

Adolescent↗

Does PGE2 act as a mediator for endothelin release?

To investigate the effect of iloprost (ZK 36374) and thromboxane synthetase inhibitor UK 38485 on endothelin release by the intestinal vascular endothelium after ischemia/reperfusion (IR) injury, five experimental groups were formed. The groups consisted of sham, control, iloprost treated (ILO), UK 38485 treated (TSI), and iloprost + UK 38485 treated (ILO + TSI) groups. The last three groups received the corresponding agents and then the superior mesenteric artery was clamped for 30 min followed by 90 min reperfusion. Endothelin levels in the portal blood and malondialdehyde (MDA), prostaglandin E2 (PGE2) and leukotriene C4 (LTC4) levels in the intestinal tissue were determined. The MDA levels increased significantly in the control group and this increase was reversed in ILO, TSI, and ILO + TSI groups, the two drugs together showing a synergistic effect in preventing lipid peroxidation. The changes in the LTC4 levels were not significant among the groups. The increased endothelin levels in the control group were reversed in ILO and TSI groups but these two agents did not have a synergistic effect. Increased PGE2 levels were reversed with iloprost but neither UK 38485 nor the combination of the two agents was effective in decreasing PGE2 levels. It is concluded that endothelin release after mesenteric IR injury is relatively unrelated to lipid peroxidation and the lipoxygenase pathway. The cylooxygenase pathway has a direct effect on endothelin release and PGE2 may act as a mediator.

Animals↗

The effect of Iloprost (ZK 36374) on isolated and transplanted pancreatic islet cells.

Several methods have been described for the prolongation of survival of isolated and transplanted islet cells. To investigate the effect of a stable prostacyclin analogue, ZK 36374 (Iloprost) on isolated and allotransplanted islet cell function, we studied 6 groups of rats: Group 1 (n = 7) animals underwent pancreatectomy and their islets were isolated and cultured by standard techniques. Group 2 (n = 8) animals were treated the same, except for the addition of Iloprost to the culture solutions. Group 3 (n = 7) animals were treated as group 1, but the isolated islets were transplanted to the subcapsular space of the left kidney of group 5 (n = 7) animals. Group 4 (n = 8) animals were treated as group 2, and the isolated islets were transplanted to group 6 (n = 8) animals. The insulin levels in the culture media obtained in group 1 and 2 were measured. In groups 5 and 6 blood glucose levels were measured and intraperitoneal glucose loading tests were performed. Histological examination was performed for both isolated and transplanted islets. The results showed that both insulin levels and histologic evaluation were better for group 2 than group 1. Animals in group 6 reached normoglycemia on the fifth day following transplantation while it was the ninth day for group 5. The intraperitoneal glucose loading test was tolerated better by group 6 animals. We conclude that Iloprost may be responsible for the improved results which seem to be due to its cytoprotective effect.

Animals↗

The role of plasma arachidonic acid metabolites in the pathogenesis and the prognosis of Henoch-Schönlein purpura.

Henoch-Schönlein Purpura (HSP) involve small vessel inflammation. Arachidonate biochemical pathways play an important role in the pathogenesis of vascular inflammation. The aim of this study was to investigate the change in the ratio of plasma arachidonic acid metabolites in the patients with HSP and evaluate the association between clinical activity and prostanoid activity in the acute phase of HSP. Plasma prostaglandin E2 (PGE2)-like activities were found to be 7.2 +/- 0.8 ng/ml in control group (n = 12) while it was 5.3 +/- 0.6 ng/ml in the patients with HSP (n = 12). Plasma leukotriene C4 (LTC4)-like activities were found to be 16.0 +/- 1.1 ng/ml in control while it was 30.9 +/- 4.3 ng/ml in the patients. The differences of LTC4-like activities and the LTC4/PGE2 ratios between the HSP patients and the controls were significant (p < 0.01, p < 0.001 respectively), but no significant difference was found in PGE2-like activities. Plasma LTC4-like activity and LTC4/PGE2 ratio were also significantly increased in the patients with high clinical score (p < 0.05, p < 0.02 respectively). These results suggested that not only cyclooxygenase products but also LTs may play an important role in vascular inflammation. Therefore LTC4/PGE2 ratio must be taken into consideration in the pathogenesis and the prognosis of HSP.

Adolescent↗