Impact of endo- and exogenous estrogens on heart rate variability in women: a review.

Measurement of heart rate variability (HRV) is an established method to assess the activity of the autonomic nervous system. The aim of this review was to examine the link between HRV, reproductive life stages and menopausal hormone therapy. A literature review was performed using the Medline database. Based on title and abstract, 45 studies were extracted out of 261 citations screened. Due to different study designs and evaluation methods, HRV indices were not directly comparable. Qualitative comparisons in between the vast majority of studies, however, demonstrated a decrease of the vagal dominance on the heart from the follicular to the luteal cycle phase, although some studies asserted no change. The intake of oral contraceptives appeared not to alter the vagal modulation of the heart. All investigations agreed on a decline of HRV towards higher sympathetic control after menopause. Different menopausal hormone therapy approaches showed a supporting impact of estrogen on HRV in most studies. A combined therapy of estrogen and progestogens revoked this benefit. Further research is needed to demonstrate how this process might be attenuated by different menopausal hormone therapies.

Antibiotic prophylaxis at urinary catheter removal prevents urinary tract infection after kidney transplantation.

BACKGROUND: Urinary tract infections (UTI) are common nosocomial infections in kidney transplant recipients, with limited evidence to guide antibiotic prophylaxis at urinary catheter removal. The aim of our study was to evaluate the effect of short-term antibiotic therapy at the moment of catheter removal after kidney transplantation. METHODS: Twenty kidney transplant recipients received 250 mg of ciprofloxacin orally twice daily 1 day before and at the day of the removal of the urinary catheter and were compared with 20 kidney transplant recipients without prophylaxis. UTI was diagnosed by use of urine culture and clinical signs. RESULTS: All patients were comparable in sex, age, etiology of end-stage renal failure, immunosuppression, donor type, and initial function. After catheter removal at the 6th postoperative day, a rapid rise of UTI in kidney transplant recipients without prophylaxis (n = 12, 60%) was observed, whereas in patients with antibiotic prophylaxis the rate of UTI could be significantly reduced to 20%. Escherichia coli was the most isolated pathogen in the patients with UTI and was detected at the catheter tip in more than 50% of cases. In 2 patients (10%) after antibiotic prophylaxis, a ciprofloxacin-resistant E coli strain was detected. CONCLUSIONS: The use of antibiotic prophylaxis during urinary catheter removal is recommended to prevent UTI in kidney transplant recipients.

Gender and strain-specific differences in the development of steatosis in rats.

Non-alcoholic fatty liver disease (NAFLD) is a common problem with a wide variety of phenotypes. While its pathogenesis is still not fully understood, several risk factors for disease progression have been identified. Therefore, defining adequate animal models may serve to unreveal the pathogenesis in NAFLD. We studied Lewis and Sprague-Dawley rats of both genders (n = 6) fed standard (Std) or high-fat (HF) diet for three weeks. Disease stage was assessed by haematoxylin-eosin, Azan Heidenheim and Oil-Red staining, apoptosis by single-stranded DNA (ssDNA) detection and liver regeneration by Ki-67 staining. Serum markers of liver injury and lipid metabolism including adipocytokines were analysed. Livers of both strains and genders fed with HF diet demonstrated evidence of steatosis. Lewis rats developed microvesicular steatosis whereas Sprague-Dawley rats presented macrovesicular steatosis accompanied by pronounced fibrosis. Female gender of both strains was associated with lower steatosis grade and higher proliferation rate (P < 0.05). Gender-specific differences were most prominent in Lewis rats on a HF diet, where females showed lower alkaline phosphatase, cholesterol, triglyceride and leptin levels and a more favourable low-density lipoprotein/high-density lipoprotein ratio than males (P < 0.05). Reverse transcriptase-polymerase chain reaction analysis was performed to demonstrate changes in expression of various genes important for liver regeneration, fibrosis and steatosis. HF diet induced downregulation of proangiogenic genes such as vascular endothelial growth factor receptor 1 and 2 (P < 0.05) in males was not present in females. In conclusion, strain and gender served major roles in disease progression. These differences should be considered when designing studies and may offer new ways to advance therapeutic strategies.

Recurrent complicated colon diverticulitis in renal transplanted patient.

Colon perforation due to diverticulitis is a life-threatening complication in the postoperative course of kidney transplantation. In the immunocompromised patient a diagnosis of diverticulitis is difficult to make. We report a 53-year-old woman being kidney transplanted 14 years ago with known diverticulosis. She was admitted with acute severe pain in the lower left abdomen. Abdominal computed tomography (CT) scan indicated a diagnosis of intestinal abscess in the small pelvis. Laparotomy showed a covered sigma perforation with abscess located in the small pelvis (Hinchey-I). Because of the immunocompromised situation of the patient we performed a Hartmann procedure. Her postoperative course was uneventful. In a 6-month interval the intestinal continuity restoration was performed. Twelve days after discharge the patient was readmitted with reduced renal function and increased infection parameters. During physical examination the abdomen was tender. The patient complained of abdominal pain in the left upper abdomen and additional pain in the left shoulder. An antibiotic therapy using ciprofloxacin was already initiated owing to a urinary tract infection. An abdominal CT scan was performed and indicated an intestinal abscess in the left upper abdomen. Laparotomy showed an abscess involving transverse colon, distal jejunum, and proximal ileum (Hinchey-II). Segmental resection of the left colonic flexure, proximal jejunum, and ileum was performed. The postoperative course was uneventful and the patient was discharged on the 8th postoperative day. The present casuistry emphasizes that the immunocompromised patient can undergo diverticulitis twice, and that primary anastomosis is a feasible option for patients with localized peritonitis due to complicated diverticulitis.

Interventional stenting for ruptured iliac aneurysm following transplant nephrectomy.

Surgical removal of a failed kidney graft may lead to a variety of postoperative complications, development of an aneurysm being a relatively rare complication. We report the case of a 34-year-old man who developed an iliac aneurysm 13 years after transplant nephrectomy. Interventional stenting was performed upon the rupture of the aneurysm. Postintervention the function of the contralateral transplanted kidney was stable and the patient recovered. An endoleak was diagnosed after 1 week, which was also stented. No operative procedure was necessary. In conclusion, even in an emergency situation interventional stenting of a false iliac aneurysm after transplant nephrectomy may be a therapeutic option.

Improved technique of heterotopic auxiliary rat liver transplantation with portal vein arterialization.

BACKGROUND AND AIMS: In acute, potentially reversible hepatic failure, auxiliary liver transplantation is a promising alternative approach. Using the auxiliary partial orthotopic liver transplantation (APOLT) method--the orthotopic implantation of auxiliary segments--most of the technical problems (lack of space for the additional liver mass, the portal vein reconstruction, and the venous outflow) are avoided, but extensive resections of the native liver and the graft are necessary. Erhard described the heterotopic auxiliary liver transplantation (HALT) with portal vein arterialization (PVA). Initial clinical results demonstrated that an adequate liver function can be achieved using this technique. We developed and improved a technique of HALT with flow-regulated PVA in the rat to perform further investigations. The aim of this paper is to explain in detail this improved experimental surgical technique. MATERIALS AND METHODS: Liver transplantations were performed in 122 male Lewis rats: After a right nephrectomy, the liver graft, which was reduced to about 30% of the original size, was implanted into the right upper quadrant of the recipient's abdomen. The infrahepatic caval vein was anastomosed end-to-side. The donor's portal vein was completely arterialized to the recipient's right renal artery in stent technique. Using a stent with an internal diameter of 0.3 mm, the flow in the arterialized portal vein was regulated to achieve physiologic parameters. The celiac trunk of the graft was anastomosed to the recipient's aorta, end-to-side. The bile duct was implanted into the duodenum. RESULTS: After improvements of the surgical technique, we achieved a perioperative survival of 90% and a 6-week survival of 80% in the last 112 transplantations. CONCLUSION: We developed a standardized and improved technique, which can be used for experiments of regeneration and inter-liver competition in auxiliary liver transplantation. Furthermore, this technique is suitable for the investigation of the influence of portal vein arterialization and portal hyperperfusion on liver microcirculation, function, and morphology.

Auxiliary partial orthotopic liver transplantation: treatment of acute liver failure in a new rat model.

BACKGROUND AND AIMS: Liver regeneration and functional interaction between native liver and graft after auxiliary partial orthotopic liver transplantation (APOLT) are not entirely understood and, therefore, require an experimental model simulating the clinical features of acute liver failure (ALF) and the surgical technique of APOLT. MATERIALS AND METHODS: ALF was induced by subtotal hepatectomy in 50 Lewis rats (200-250 g). Sham operation (I), ALF without treatment (II), ALF with portocaval shunt for decreasing blood flow of the remnant liver (III), and ALF treated by APOLT (IV) were performed. The auxiliary graft represented a left donor liver lobe which was orthotopically implanted using a microsurgical technique including reconstruction of the graft artery and internal biliary drainage. Operative outcomes, serum chemistry and histopathological findings were examined up to the 14th day. RESULTS: ALF without treatment (groups II and III) led to a small droplet fatty degeneration in the hepatocytes and a significant increase of liver parameters until the death of the animals within the first two postoperative days ( P<0.05). After APOLT (group IV), 80% of the animals survived up to the 14th day, revealing significantly decreased liver parameters ( P<0.05), a well-perfused graft and an up to five times increased native liver size with normal architecture. CONCLUSION: This new rat model simulates the clinical features of an ALF treated by APOLT and is especially interesting for further basic research on the interaction between native liver and auxiliary graft after APOLT.