Erdem Okay

Piperacillin with and without Tazobactam against Extended-Spectrum Beta-Lactamase-Producing Pseudomonas aeruginosa in a Rat Thigh Abscess Model

Background: We compared the antibacterial effect of piperacillin, piperacillin-tazobactam and imipenem in a paired rat thigh abscess model. Methods: Two abscesses were provoked in the thighs of rats, one on the right with an extended-spectrum beta-lactamase (OXA-14)-producing Pseudomonas aeruginosa (Ps-162) and the other on the left thigh with a control strain. Results: The colony counts from the abscesses in log 10 colony-forming units per gram (mean ± SD) in the imipenem group were 2.78 ± 1.71 and 3.19 ± 1.66, in the piperacillin-tazobactam group 4.36 ± 0.23 and 2.44 ± 1.97, and in the piperacillin group 4.44 ± 0.21 and 3.71 ± 0.99 for Ps-162 and the control strain, respectively. The mean colony counts were significantly different (p < 0.05) between Ps-162 and the control strain in the piperacillin and piperacillin-tazobactam groups. Conclusion: These data showed that piperacillin and piperacillin-tazobactam were significantly less effective against extended-spectrum beta-lactamase-producing P. aeruginosa, while imipenem was equally effective against both Ps-162 and the control strain in this abscess model.

Cross Effects of Resveratrol and Mesenchymal Stem Cells on Liver Regeneration and Homing in Partially Hepatectomized Rats

In this study, we examined the effect of preoperatively administered resveratrol (RV) and mesenchymal stem cells (MSCs) on regeneration of partially hepatectomized rat liver. We also evaluated the effect of RV on homing of MSCs. MSCs were isolated from bone marrow and cultured in vitro. Wistar albino rats were randomly divided into four groups. In groups, rats received (1) no treatment, (2) single dose RV, (3) MSCs and (4) RV plus MSCs before partial hepatectomy (PH). Injected MSCs were traced by labeling them with green fluorescent protein, and liver regeneration was determined by comparison of liver weight gain, histological examination and immunohistochemical staining with proliferating cell nuclear antigen (PCNA) for mitotic cells. The expression levels of tumor necrosis factor –alpha (TNF-α), interleukin-6 (IL-6) and hepatocyte growth factor (HGF) were also determined in the parafin sections of liver specimens with immunohistochemical staining. Administration of RV and MSCs separately or together enhanced liver regeneration despite decreasing the TNF-α and IL-6 expression. This positive contribution was probably due to direct raising effect on HGF for RV and HGF expression for MSCs that we demonstrated with immunohistochemical staining. Additionally, RV increased the homing of MSCs in liver probably related to life prolonging effect on MSCs. These results indicate that preoperative RV as well as MSCs application enhances liver regeneration after partial hepatectomy in rats. Paying attention to RV about the effect on liver regeneration and homing of MSCs might be the goal of further investigations.

Investigation of the Mechanism of Nicotine-Induced Relaxation in Guinea Pig Gallbladder

BACKGROUND Muscular contraction of the gallbladder is the primary determinant of bile delivery into duedonum. Gallbladder filling and emptying are influenced by both inhibitory and excitatory stimuli, and NO plays a key role in normal relaxation. In this study, to determine whether nicotine acts on the gallbladder muscle, the mechanism of its effect on strips of guinea pig gallbladder was studied in vitro. MATERIALS AND METHODS Guinea pig gallbladder muscle strips were mounted in organ bath with modified Krebs-Henseleit solution and aerated with Carbogen. Tension was measured with isometric force transducers, and muscle relaxation was expressed as percent decrease of precontraction induced by carbachol. RESULTS Nicotine produced concentration dependent relaxation when preparations were precontracted by carbachol (10(-6) M). Nicotine-induced relaxation was 51.6 +/- 3.2% of phenylephrine contraction and was not affected by guanethidine (10(-5) M), propranolol (10(-6) M), hexamethonium (10(-4) M), indomethacin (10(-5) M), N(w)-nitro L-arginine methyl ester (L-NAME) (3 x 10(-5) M), methylene blue (10(-5) M), glibenclamide (10(-5) M), clotrimazole (10(-6) M), tetraethylammonium (3 x 10(-4) M), or 4-aminopyridine (10(-3) M). Nicotine did not exhibit a calcium antagonizing effect. CONCLUSIONS From these results, we concluded that nicotine-induced relaxation of the guinea pig gallbladder is not mediated by the release of noradrenaline, nitric oxide (NO), prostaglandins, or a related substance, or by the activation of potassium channels, or by the stimulation of nicotinic cholinoceptors. Further work is needed to determine the cellular mechanism(s) of action by which nicotine acts on gallbladder smooth muscle.

N-ACETYLCYSTEINE IMPROVES INTESTINAL BARRIER IN PARTIALLY HEPATECTOMIZED RATS

Background:  Translocating enteric bacteria play an important role in the development of infections following partial hepatectomy. The intestine itself is the first line of defence against bacterial translocation (BT). We investigated the effect of N‐acetylcysteine (NAC) on BT and the intestinal wall.

Rett syndrome with colon cancer presented with sigmoid volvulus: Report of a case

INTRODUCTION Rett syndrome is a progressive neurodevelopment disorder in which MECP gene mutations are responsible and might be related to cancer. PRESENTATION OF CASE A 22 year-old girl with Rett syndrome was hospitalized for abdominal distention and shock. Abdominal tenderness and distention were revealed in physical examination. Radiological investigations revealed sigmoid volvulus and colonic obstruction. Sigmoid volvulus, sigmoid colon perforation due to sigmoid cancer with liver metastasis were observed at laparotomy. Hartman procedure performed. The patient died on the second postoperative day. DISCUSSION Rett syndrome has several gastrointestinal pathologies related with inadequate parasympathetic control. Genetic mutations in methyl-CpG-binding protein 2 (MECP2) which has role in several cancer mechanisms is the reason of Rett syndrome. Colon cancer with the underlying gastrointestinal pathologies complicated our case. CONCLUSION Rett syndrome patients need a high level of concern for gastrointestinal emergencies with cancer risk.

N-Acetylcysteine improves disturbed ileal contractility following partial hepatectomy in rats.

Background and Aims:  It is well known that disturbed intestinal motility and bacterial overgrowth may occur following partial hepatectomy. These events have been followed by the translocation of enteric bacteria that play a major role in the development of infections. We designed the present study to evaluate the effect of N‐acetylcysteine (NAC) on ileal muscle contractility as an indication of intestinal motility.

Pankreatikoduodenektomi Operasyonu Sonuçları: 71 Olguluk Tek Merkez Deneyimi

Aim: To retrospectively evaluate the results our pancreaticoduodenectomy surgeries in terms of morbidity and mortality rates as well as safety. Materials and methods: Medical records of 71 patients, who underwent pancreaticoduodenectomy surgery between January 2007 and September 2012 at Department of General Surgery, Kocaeli University School of Medicine, were examined retrospectively. Age, sex, the type and localization of the lesion, surgical properties and postoperative complications were studied. Results: A total of 71 patients (48 male, 23 female) with a mean age of 59.9 years who underwent pancreaticoduodenectomy were included in the study. Forty two patients (59%) had pancreatic head malignancies, 19 patients (27%) had ampulla malignancies, 4 patients (5.5%) had duodenum malignancies and 4 patients (5.5%) had common bile duct malignancies. Two of our cases (3%) underwent surgery for pancreatitis. Surgery related mortality rate was 2.8% (2 cases). The most frequently encountered complications were delay in gastric emptying (19%), pancreatic fistula (14%) and wound infection (10%). Postoperative morbidity rate was detected to be 28%. Conclusion: Pancreatic and other periampullary tumors are serious clinical problems that cause morbidity. Traditionally, these patients have a dark prognosis but correct staging and appropriate patient selection allow better results. Surgical resection, the one reason for long-term survival, should be preferred whenever possible. In conclusion, we have found out that pancreaticoduodenectomy surgery is an effective and safe surgical method in the treatment of pancreas and common bile duct problems. This surgical procedure can be performed with low morbidity and mortality rates in experienced but low-density centers. Key Words: Pancreaticoduodenectomy; Pancreas tumors; Periampullar region tumors; Mortality; Morbidity.

Hepatocellular carcinoma presenting as a huge intra-abdominal mass: a case report.

Hepatocellular carcinoma (HCC) is the most common primary malignant tumor of the liver and is generally associated with hepatitis B or C virus-related cirrhosis. A giant intra-abdominal HCC mass that fills nearly the whole abdomen is not often reported in the literature. In this report, we present a case in which a patient with hepatitis B developed a giant intra-abdominal mass that originated from segment three of the liver and infiltrated the stomach and transverse colon. We were able to resect the tumor without leaving any tumor tissue behind. Although HCC presenting as a huge mass with invasion of the gastrointestinal tract is uncommon, this pathology should be considered in the differential diagnosis of giant intra-abdominal masses. The case presented here also indicates that surgical resection is possible in selected patients.

Resveratrol attenuates both small bowel and liver changes in obstructive jaundice.

BACKGROUND It is well known that mucosal changes and alterations in liver function occur in the experimental obstructive jaundice model. AIMS We aimed to evaluate the effect of resveratrol on obstructive jaundice-induced changes in the small bowel mucosa and liver using ischaemia-modified albumin as a marker of oxidative damage. STUDY DESIGN Animal experimentation. METHODS The study used a rodent experimental model of obstructive jaundice, including a sham group (1), a control group (2), and a study group (3). Wistar albino rats were used. Jaundice was produced by ligation of the bile duct in Groups 2 and 3. In Group 3, resveratrol was administered intraperitoneally for 14 days. RESULTS In terms of the structure and the size of the mucosal villi, significant thickening and blunting were detected in Group 2 compared with Group 1. These changes were significantly less noticeable in Group 3 compared with Group 2. Levels of ischaemia-modified albumin were significantly higher in Group 2 compared with those in Group 1, and they were significantly decreased in Group 3 compared with Group 2. CONCLUSION Resveratrol administration to obstructive jaundiced rats reduced the organic effects of obstructive jaundice on small bowel mucosa and liver oxidative stress. We believe that this reduction might attenuate bacterial translocation and systemic effects of secreted cytokines.