Ahmet Ender Demirkiran

Nitric oxide regulates bacterial translocation in experimental acute edematous pancreatitis

Background/Aims: The role of nitric oxide (NO) in bacterial translocation (BT) associated with acute pancreatitis is controversial. We investigated the effects of the NO synthase substrate, L-arginine, and the NO synthase inhibitor, N-nitro-L-arginine methyl ester (L-NAME), on BT in caerulein-induced acute pancreatitis in rats. Methods: Acute pancreatitis was induced by subcutaneous injections of caerulein (12 µg/kg) at 6-hour intervals for 2 days. Subcutaneous injections of L-arginine (100 mg/kg) or L-NAME (10 mg/kg) were administeredonce daily for 2 days. At 48 h, pancreatic injury and BT to the mesenteric lymph nodes (MLN), liver, and peritoneum were assessed. Results: Compared with controls, rats that received caerulein injections alone had increased BT to the MLN and pancreatic inflammatory changes. L-Arginine significantly reduced the inflammation and BT caused by caerulein. L-NAME did not significantly alter pancreatic inflammation. Although caerulein + L-NAME-treated rats had increased BT to the peritoneum, MLN, and liver compared with controls, rates of BT did not significantly differ between caerulein alone- and caerulein + L-NAME-treated rats. Conclusion: In acute edematous pancreatitis, BT is increased and is regulated by NO. NO substrates limit BT and pancreatic inflammation associated with acute pancreatitis, probably by their bactericidal actions and ability to improve pancreatic blood flow.

Occult papillary thyroid carcinoma presenting as a parapharyngeal metastasis

The neoplastic involvement of the parapharyngeal space is a rare condition that represents only 0.5% of all head and neck tumors.1-3 The benign salivary gland tumors and tumors of neural tissue origin constitute the great majority of these cases. 3-6 To encounter a metastatic thyroid cancer in the parapharyngeal space is an extremely unusual occurrence. The literature review showed only six cases published previously.7-*2 In this article, we report a patient presenting with a left parapharyngeal mass. The pathological examination showed a metastatic thyroid papillary cancer. Besides the unusual localization of the lesion, this case also confirms the anatomic study of Rouviere13 showing the existence of lymphatic channels between the thyroid lymphatics and the parapharyngeal space.

C-reactive protein may be a marker of bacterial translocation in experimental intestinal obstruction.

Background:  C‐reactive protein (CRP) is used as a marker of intestinal ischaemia. This study evaluated whether CRP levels can be used to detect ischaemia‐induced (strangulated) intestinal obstruction and subsequent bacterial translocation.

Effects of Laparoscopic Models on Anaerobic Bacterial Growth with Bacteroides fragilis in Experimentally Induced Peritonitis

BACKGROUND Previous reports of recurrent intra-abdominal abcess formation after the laparoscopic treatment of perforated acute appendicitis led us to investigate the possible effects of gas insufflation on the spread of infection. We previously showed that Escherichia coli counts were significantly higher in a laparoscopy group that underwent carbon dioxide (CO2) insufflation than in control and laparotomy groups. The aim of this study is to investigate the effects of intra-abdominal CO2 and nitrous oxide (N2O) insufflation on anaerobic bacterial growth in a rat model. METHODS A standard strain of Bacteroides fragilis (ATCC 25285) was injected intraperitoneally (1 x 10(6) cfu/mL per kilogram) in 40 Wistar rats under sterile conditions. Forty rats with induced peritonitis were randomly divided into five groups: control, laparotomy, CO2 insufflation, N2O insufflation, and one group without pneumoperitoneum. Eight hours after the intraperitoneal injection of B. fragilis, peritoneal aspirates were obtained and inoculated onto Brucella agar. At the sixteenth hour of induced peritoneal infection (corresponding to hour 8 in the laparoscopy groups) all animals underwent laparotomy; peritoneal aspirates were obtained and inoculated into Brucella agar for bacterial counts. The colonies of B. fragilis were counted manually, and the results were expressed as the mean number of colony-forming units per milliliter. RESULTS No significant differences in microorganism counts were noted between the study groups before the procedure (p>.05 for all comparisons). We observed a significant increase in the number of bacteria (mean +/- SD) in the CO2 insufflation group between hour 8 and hour 16 of peritoneal contamination. CONCLUSION The results suggest that CO2 insufflation may promote the growth of intra-abdominal anaerobic bacteria. Such bacterial growth may lead to intra-abdominal abcess formation or cause localized peritonitis to develop into generalized peritonitis. We suggest that laparoscopy without pneumoperitoneum may be preferred in patients with peritonitis.

Effects of pneumoperitoneum with or without colostomy on rat colonic anastomotic healing

Background:  Elevated intra‐abdominal pressure and colostomy have adverse effects on colonic anastomoses. The aim of the present study was to investigate the effects of laparoscopic colon surgery with and without diverting colostomy on healing of colonic anastomoses in an experimental model.

Effect of abdominal insufflation on bacterial growth in experimental peritonitis.

BACKGROUND Perforated appendicitis can be treated laparoscopically, but this approach is associated with a higher rate of intra-abdominal abscess. Pneumoperitoneum impairs the clearance of bacteria from the peritoneal cavity in experimental models of peritonitis. The aim of this study was to investigate the effects of intra-abdominal gas insufflation on bacterial growth in a rat model. MATERIALS AND METHODS The effects of intraperitoneal insufflation with different gases and a gasless model on bacterial proliferation in a setting of Escherichia coli-induced experimental peritonitis were studied in a rat model. Saline (0.25 mL) was given intraperitoneally to six Wistar male rats as the sham group. Escherichia coli (1.5 x 10(9) cfu/mL per kilogram) was injected intraperitoneally into to 24 rats. Microorganism counts were taken after 8 hours, and rats were divided into three groups: group 1, CO2 insufflation; group 2, N2O insufflation; and group 3, no insufflation. Microorganism counts were repeated 8 hours after the procedure (at 16 hours postinjection). RESULTS The difference in microorganism counts between 8 and 16 hours were significant in the CO2 and N2O insufflation groups (P < 0.05) but not in the group without pneumoperitoneum. CONCLUSIONS Abdominal insufflation may promote intra-abdominal bacterial growth or decrease intra-abdominal bacterial clearance.

Is synchronous bowel anastomosis safe

Abstract In this study, we investigated the effects of synchronous anastomosis on intestinal healing in experimental colonic resection. Sprague-Dawley rats were randomized into 3 groups; control (group I), single anastomosis (group II) and synchronous (double) anastomosis (group III). Single and proximal anastomoses were located 3 cm distal to caecum, and distal anastomoses were done 3 cm distal to them. On the 7th postoperative day, bursting pressure, hydroxy-proline level and histology of the anastomotic site were assessed. Bursting pressures and hydroxyproline levels indicated that impaired healing of proximal anastomoses in group III was evident. Proximal anastomoses in group III had the lowest hydroxyproline value and bursting pressure level. Significant fibrosis was observed in the histological examination of distal anastomoses in group III. Double colonic anastomoses is not as safe as single anastomoses and involves additional risk. The healing of proximal anastomosis is significantly altered after experimental synchronous resection.

The Effects of Nitric Oxide Supplementation and Inhibition on Bacterial Translocation in Bile Duct Ligated Rats

Abstract Obstructive jaundice promotes bacterial translocation from the gut, but the role of nitric oxide is controversial in this process. We studied the effects of nitric oxide synthase substrate, L-arginine, and nitric oxide synthase inhibitor, NG-nitro-¿-arginine methyl ester, on bacterial translocation in bile duct ligated rats. The animals were randomized into five groups; control, sham, common bile duct ligation alone, nitric oxide inhibition, and nitric oxide supplementation. Obstructive jaundice was performed with common bile duct ligation. ¿-arginine or NG-nitro-¿-arginine methyl ester was injected once daily for 14 days. Blood bilirubin level, liver histology, and bacterial translocation to the mesenteric lymph nodes as well as to the liver were assessed. The ¿-arginine supplemented group had the lowest bacterial translocation rate, but the most prominent hepatic fibrosis. Nitric oxide inhibition increased bacterial translocation to the mesenteric lymph nodes. Therefore, the administration of nitric oxide donor or inhibitor acts as a significant regulatory factor for bacterial translocation in obstructive jaundice.

Strangulated ventral hernia model in rats.

This study was performed to describe a new model of strangulation obstruction mimicking the situations relevant to abdominal hernias. The strangulation obstruction was induced either by intra-abdominal ligation of an ileal segment 2 cm in length ( n = 20) or by a pursestring suture around a fascial defect with a strangulated intestinal loop placed subcutaneously ( n = 20). Ten animals served as sham operated controls ( n = 10). All animals were euthanized at 12 h postoperatively; strangulated ileum segments were collected for histopathological examination. Microscopic injury scores were similar in both strangulation groups, which were significantly different from the control group ( p < .001). The model described here seems to be appropriate for use in further experimental studies concerning strangulation obstruction injury and its consequences, with the added advantage of visualization of the strangulated intestinal loop beneath the skin.

Laparoskopik appendektomi açık girişimin güvenilir bir alternatifidir

Laparoscopic appendectomy has progressed to become a reliable surgical procedure in recent years. However, there are some pros and cons comparable with open appendectomy. Materials and methods: The results of 91 patients with acute appendicitis who were operated either with laparoscopic or open technique were retrospectively evaluated. Results: Laparoscopic appendectomy was performed in 28 (30.7%) patients, whereas 63 (69.3%) cases underwent open procedure. Two (6.6%) laparoscopic procedures were converted to open because of perforation and anatomical problems. The duration of operation, hospital stay, and rate of complications did not differ among groups (p>0.05). One patient in each group developed intraabdominal abscess. Conclusions: Laparoscopic appendectomy does not increase postoperative complications as previously speculated, and therefore is a reliable alternative for open appendectomy.