A. Özdemir Aktan

Different kinds of reactive oxygen and nitrogen species were detected in colon and breast tumors

Several studies have shown the involvement of reactive oxygen species (ROS; O2*-, hypochlorite, hydroxyl radical, hydrogen peroxide) in carcinogenesis. With certain pathologies, nitric oxide (NO) is formed and can interact with superoxide radical (O2*-) resulting in the propagation of the highly reactive species, peroxynitrite. In order to study the molecular mechanisms underlying the ability of reactive oxygen and nitrogen species (RONS) to mediate carcinogenesis, we have measured ROS, NO, and peroxynitrite content of cancerous tissues obtained from colon and breast carcinoma cases by chemiluminescence technique. All ROS were significantly increased in cancerous colon tissues with hypochlorite making the most important contribution and suggesting the role of inflammatory cells. NO was also increased and the peroxynitrite concentration was higher in cancerous samples. For breast carcinoma cases, only O2*- was significantly increased. Hypochlorite was not detected excluding the contribution of inflammatory cells. NO concentrations were not significantly different, therefore, ROS might originate by change in the redox state of the tissue.

Enterostomy Site Hernias: A Clinical and Computerized Tomographic Evaluation

PurposeParastomal hernia continues to be an important clinical problem with a reported incidence of up to 50 percent. In studies using computerized tomography in selected cases for detection of parastomal hernia, physical examination alone was underestimating the true incidence. Also after closure of the enterostomy, the ostomy site could still be a potential area of herniation. In this study in addition to physical examination, we used computerized tomography to determine the true incidence of parastomal hernia and ostomy closure site hernias.MethodsWe examined patients with enterostomies and with closed enterostomy sites both with physical examination and computerized tomography for the detection of hernias, hernia content, and relation to rectus muscles. Risk factors for hernia formation, such as age, gender, body mass index, associated medical problems, and surgical site infections, were determined.ResultsEvaluation of 23 patients with ostomies resulted in 52 percent incidence of parastomal hernia, whereas the addition of tomography examination gave a corrected incidence of 78 percent. In a second subset of 23 patients with closed ostomies, although 26 percent of the patients were found to have ostomy site hernias with physical examination alone, this incidence increased to 48 percent when combined with computerized tomography. The potential risk factors for hernia formation, such as body mass index, surgical site infection, and ostomy site whether pararectus or transrectus, were not proven to have a significant role in this study.ConclusionsParastomal hernia and closed ostomy site incisional hernias have a high incidence, and computerized tomography has been shown to be a valuable diagnostic tool.

BQ-123, a specific endothelin (ETA) receptor antagonist, prevents ischemia-reperfusion injury in kidney transplantation

We studied the effects of the specific endothelin (ETA) receptor antagonist, BQ-123, on reperfusion injury in a rat model of kidney transplantation. First, Sprague-Dawley rats were divided into three groups: a sham nephrectomy (SNEPH), an autotransplantation (AUTO-Tx), and an allotransplantation (ALLO-Tx) group. In a fourth group, ALLO-Tx+BQ, allografts were flushed with 20 μg BQ-123 containing cold Ringers lactate before transplantation. For the allograft groups, kidneys from white Wistar albino rats were transplanted into allogeneic Sprague Dawley recipients. Grafts were allowed 120 min of reperfusion after 40 min of cold ischemia. ET-1,2 plasma concentrations in the renal venous blood, and kidney tissue prostaglandin (PG) E2 and leukotriene (LT) B4 levels were studied. Diene conjugates (DC), hydroxyalkanals (HAA), hydroxyalkenals (HAE) and malondialdehyde (MDA) levels, as the products of lipid peroxidation, and protein carbonyls (PC) and protein sulphydryls (PS), as the parameters of protein oxidation, were also analyzed in the kidney tissue. Plasma ET concentrations increased significantly in the AUTO-Tx and ALLO-Tx groups (P<0.05 and P<0.01, respectively) but this increase was reversed in the ALLO-Tx+BQ group. None of the lipid peroxidation products except DCs (P<0.05) increased in the AUTO-Tx group, whereas they all increased in the ALLO-Tx group (P<0.01). Protein oxidation parameters also changed significantly (P<0.01) in the ALLO-Tx group but did not in the AUTO-Tx group (P<0.05). The differences in PGE2 and LTB4 levels were not significant. Histopathologic examination revealed prominent glomerular and tubular injury in the AUTO-Tx and ALLO-Tx groups but less in the ALLO-Tx+BQ group. In the last group, all parameters of lipid peroxidation (P<0.001 for all) and PCs decreased, and PSs were preserved (P<0.001 for both) when compared with the AUTO-Tx and ALLO-Tx groups. We conclude that BQ-123, in addition to inhibiting the binding of ET-1,2 to the ETA receptor, may also inhibit the release and/or synthesis of ET-1,2 and prevent reperfusion injury in kidney transplantation.

Early Prediction of Normocalcemia after Thyroid Surgery

Hypocalcemia is the principal factor that determines length of hospital stay after thyroid surgery. Seventy-nine patients who underwent thyroidectomy were prospectively evaluated in order to define risk factors for postoperative hypocalcemia. Serum samples were taken postoperatively at 8, 14, 24, and 48 hours to measure total calcium levels. The slope of change in serum calcium level between each sample time was calculated. Patients were also examined for age, gender, surgical indications, type and extension of surgery, thyroid function, presence of substernal extension, initial operation versus reoperation, and application of parathyroid autotransplantation. All comparisons were made between hypocalcemic and normocalcemic groups. Hypocalcemia occured in 15 (19%) patients. In univariate analysis, type and extent of thyroidectomy, serum calcium levels at each time point, as well as the slope of change in serum total calcium levels between 8 and 14 hours were found to be significantly predictive of normocalcemia. All patients who underwent hemithyroidectomy and who had a positive or neutral slope of calcium change after surgery remained normocalcemic. By multivariate logistic regression analysis, only the slope of change in calcium levels within the first 14 postoperative hours independently predicted calcium status after thyroidectomy. All patients who undergo unilateral thyroid surgery who have a positive/neutral slope of change in serum total calcium levels within the first 14 hours after surgery can be safely discharged early if they have no other risks.

The cytoprotective effects of verapamil and iloprost (zk-36374) on ischemia reperfusion injury of kidneys

We investigated the cytoprotective effects of verapamil, a Ca channel blocker, and of iloprost (ZK 36374), a stable prostacyclin analogue, on ischemia/reperfusion (I/R) injury in Wistar albino rat kidneys that were subjected to 60 min of warm ischemia and reperfusion. The groups included sham, ischemia-untreated (ISCH), verapamil-treated (VER), iloprost-treated (ILO), and verapamil + iloprost (VER+ILO)-treated rats. The 7-day survival of all the treated groups was better than that of the ISCH group. The creatinine concentration on the 3rd day was significantly lower in the VER+ILO group than in the ISCH group. Serum creatinine on day 3 was also low in the VER+ILO groups compared to the ISCH group, although the differences were not significant. The creatinine values on day 7 were significantly lower in the VER and ILO group than in the control, VER, or ILO groups. The malondialdehyde (MDA) concentrations of the kidney cortex tissue after reperfusion in all groups were higher than normal. The tissue-reduced glutathione (GSH) concentrations of the kidneys sampled immediately after reperfusion were significantly lower in the ISCH group than in all of the other treated groups. These results indicate that although verapamil and iloprost have independent cytoprotective effects on 60-min warm ischemia/reperfusion injury of rat kidneys, the protection afforded when both drugs are combined is synergistic. The mechanism of cytoprotection is not limited to the suppression of lipid peroxidation, and a nearly complete protection of reperfusion injury can be obtained by such an intervention.

Bombesin Ameliorates Colonic Damage in Experimental Colitis

In the present study we investigated thepossible therapeutic effects of bombesin on anexperimentally induced colitis model in rats.Inflammation of the colon was induced by a singleintracolonic administration of 30 mg of 2,4,6-trinitrobenzene sulfonic acid(TNBS) at 8 cm from the anus. Immediately after theinduction of colitis, some rats were given bombesin (10μg/kg; subcutaneously) three times a day for 14 days, while another group received vehicletreatment. On day 14, the rats were decapitated andplasma carbonyl content and tissue myeloperoxidaselevel, as an index of granulocyte infiltration intointestinal tissue, were determined in order to obtain anobjective evaluation of colonic injury. In the colitisgroup, increased macroscopic damage score, elevated MPOlevel and high plasma carbonyl content, together with the microscopic appearance revealed severeinflammatory changes resembling IBD. Bombesin treatmentattenuated the TNBS-induced colonic damage andstimulated histopathologically apparent mucosalproliferation, suggesting that bombesin may play a role inprotecting gut integrity.

Captopril increases endothelin serum concentrations and preserves intestinal mucosa after mesenteric ischemia-reperfusion injury

Endothelial cells modulate the tone of the underlying smooth muscle by generating endothelium-derived relaxing and constricting factors. Captopril (CPT), unlike other angiotensin-converting enzyme (ACE) inhibitors, contains a sulfhydryl (-SH) group and can act as a free radical scavenger. Iloprost (ILO) is a synthetic analogue of prostacyclin and mimics the effects of this compound. This study was designed to investigate the effect of ILO and CPT on the mechanism of endothelin (ET) release after mesenteric ischemia-reperfusion (I/R) injury in the rat. Sprague-Dawley rats were divided into five groups: sham-operated, control, ILO (25 μg/kg), CPT (10 μg/kg), and ILO+CPT. The superior, mesenteric artery was occluded for 30 min and then allowed 90 min of reperfusion, except in the sham-operated group, and the corresponding agents were given to the treated groups prior to I/R injury. After I/R injury, portal venous blood was obtained for ET assay, and ileal tissue samples were also obtained for the determination of malondialdehyde (MDA), prostaglandin E2 (PGE2) and leukotriene C4 (LTC4) and for histopathological examination. MDA levels were significantly lower in the CPT, ILO and, ILO+CPT groups than in the control group, indicating the inhibition of lipid peroxidation in all groups. ET levels increased in the control group, and this increase was reversed with ILO. In the CPT group, ET levels were significantly increased, and the addition of ILO did not affect this increase. Significant cytopreservative effect was achieved with ILO and CPT, the latte being more prominent histopathologically. CPT exerts a significant protective effect on the intestinal mucosa after I/R injury. This protection is accomplished by increased ET levels and seems to be unrelated to its inhibitory effect on lipid peroxidation and also unrelated to the arachidonic acid cascade.

The Use of Bonewax to Control Massive Presacral Bleeding

Abstract.Massive presacral bleeding during retroperitoneal resection is unusual, and can be difficult to control. We describe a technique for managing this complication whereby bonewax is pushed through the presacral fascia and periosteum directly into the bleeding point in the sacrum, followed by abdominal packing. This maneuver proved successful for achieving hemostasis when we recently encountered this intraoperative complication.

Anal Surgical Techniques in Early Ottoman Period Performed by Şerefeddin Sabuncuoğlu

One of the interesting fields of research is the history of surgical development throughout the centuries. It is well known that the history of surgery is as old as humans on earth. Although the ancients lacked the anatomic and pathophysiologic bases of diseases, they tried to treat wounds, stop hemorrhages, drain abscesses, and reduce fractures. Egyptians, Indians, and later on Greeks and Romans dealt with general medicine and surgery. Many historical physicians and surgeons emerged from these civilizations and later on were considered to be the fathers of medicine and surgery. In the Middle East, Arabic interest in medicine began evolving and progressing in the 9th century, influenced mostly by Greek, Roman, and Persian medicine. In the Islamic medical literature is the famous surgeon Ebu-El kasım El Zehrawi (Albucasis; 936– 1013), known as the father of operative surgery, who wrote his book El-Tasrif in 30 tomes and specialized 3 of them for surgery. Three hundred years later, Şerefeddin Sabuncuoğlu (1385–1468) wrote his book Cerrahiyet-ül Haniyye (Imperial Surgery) in Amasya, Turkey, when he was 80 years old, and considered El-Zehrawi (Albucasis) to be his master and reference, and was the first to write a surgery book in Turkish [1]. Although Cerrahiyet-ül Haniyye did not include many innovations in surgical principles or techniques, and was mostly a Turkish version and revision of what was already known at that time, it was the first surgical textbook containing illustrations and colored miniatures of the surgical techniques and instruments he used. As he was interested in drawing, Sabuncuoğlu illustrated the book himself. This book consists of 206 pages and 193 topics dealing with all fields of surgery. There are 3 known handwritten copies of the book, 1 in Paris and 2 in Istanbul. Two of them were originally written by the author himself [2–4].

Whey Feeding Suppresses the Measurement of Oxidative Stress in Experimental Burn Injury

PurposeBurns cause thermal injury to local tissue and trigger systemic acute inflammatory processes, which may lead to multiple distant organ dysfunction. We investigated the protective effect of dietary whey supplementation on distant organs in a rat model.MethodsForty-eight rats were divided into six groups of eight: groups 1 and 2 were the controls, fed a standard diet and a whey-supplemented diet, respectively; groups 3 and 4 were fed a standard diet and subjected to burn injury; and groups 5 and 6 were fed a whey-supplemented diet and subjected to burn injury. We measured the oxidative stress variables, as well as glutathione in the liver and kidney, and histologically examined skin samples obtained 4 h (groups 3 and 5) and 72 h (groups 4 and 6) after burn injury.ResultsGlutathione (GSH) levels remained the same in the liver but were slightly elevated in the kidneys after burn injury in the rats fed a standard diet. Whey supplementation caused a significant increase in hepatic GSH levels 4 h after burn injury. Moreover, there was a significant rebound effect in the liver and kidney GSH levels after 72 h and whey supplementation potentiated this effect. Hepatic and renal lipid peroxide levels were also increased 4 h after burn injury in the rats fed a standard diet. Whey supplementation significantly suppressed the burn-induced increase in hepatic and renal lipid peroxide levels. Histological examination revealed that although whey supplementation resulted in decreased subepidermal inflammation, the indicators of wound healing and collagen deposition were not improved.ConclusionWhey pretreatment suppressed hepatic and renal oxidative stress measurements after experimental burn injury.