Presentation and management of cystic neoplasms of the pancreas.

Pancreatic cystic neoplasms are uncommon, but it is important to differentiate them from pseudocysts and ductal adenocarcinoma. A retrospective review was performed to determine distinguishing characteristics and optimal treatment. In 51 patients operated on between 1981 and 1994 at a referral center, the following cystic neoplasms were found: 20 serous cystadenomas, 10 mucinous cystadenomas, 11 mucinous cystadenocarcinomas, five cases of mucinous ductal ectasia, and five papillary cystic neoplasms.

The Ras mutant D119N is both dominant negative and activated.

The introduction of mutation D119N (or its homolog) in the NKxD nucleotide binding motif of various Ras-like proteins produces constitutively activated or dominant-negative effects, depending on the system and assay. Here we show that Ras(D119N) has an inhibitory effect at a cell-specific concentration in PC12 and NIH 3T3 cells. Biochemical data strongly suggest that the predominant effect of mutation D119N in Ras-a strong decrease in nucleotide affinity-enables this mutant (i) to sequester its guanine nucleotide exchange factor, as well as (ii) to rapidly bind GTP, independent of the regulatory action of the exchange factor.

Guanosine triphosphatase stimulation of oncogenic Ras mutants.

Interest in the guanosine triphosphatase (GTPase) reaction of Ras as a molecular drug target stems from the observation that, in a large number of human tumors, Ras is characteristically mutated at codons 12 or 61, more rarely 13. Impaired GTPase activity, even in the presence of GTPase activating proteins, has been found to be the biochemical reason behind the oncogenicity of most Gly12/Gln61 mutations, thus preventing Ras from being switched off. Therefore, these oncogenic Ras mutants remain constitutively activated and contribute to the neoplastic phenotype of tumor cells.

Selective Hydrovinylation of Styrene in a Membrane Reactor: Use of Carbosilane Dendrimers with Hemilabile P,O Ligands.

A codimerization of styrene and ethene can be carried out continuously in a nanofiltration membrane reactor with dendritic Pd complexes such as 1. The selectivity of the reaction is increased considerably under continuous conditions. The activity and selectivity of monomeric model complexes and the dendritic catalysts were compared in batch reactions.

Laparoscopic intraperitoneal onlay inguinal herniorrhaphy.

Background: This study presents intermediate follow-up data on a randomized prospective series of patients undergoing either a modified laparoscopic intraperitoneal onlay mesh herniorrhaphy (IPOM) or conventional anterior inguinal herniorrhaphy (CH).

Methods: All patients from two university affiliated hospitals with primary or recurrent inguinal hernias were recruited for randomization to either the IPOM technique utilizing a meshed expanded polytetrafluorethylene (ePTFE) soft tissue patch or CH. Follow-up data were gathered from postoperative clinic visits and telephone and mail surveys.

Littoral cell angioma of the spleen.

Littoral cell angioma (LCA) is a rare benign vascular tumor of the spleen. LCA most commonly presents with constitutional symptoms (low grade fever and fatigue) and signs of hypersplenism (anemia and thrombocytopenia). Radiographically and at gross pathology an enlarged spleen containing multiple nodules is most commonly seen.

Trends in bile duct injuries from laparoscopic cholecystectomy.

Bile duct injuries are a serious complication of cholecystectomy. Laparoscopic cholecystectomies (LC) were originally associated with an increased incidence of injuries. Patients referred to a tertiary center were reviewed to assess the trends in the number, presentation, and management.

Liver resection using total vascular exclusion.

Background: Total vascular exclusion (TVE) is a technique of liver resection that includes controlling both the suprahepatic and infrahepatic vena cava in addition to portal inflow at the time of parenchymal transection. We report a series of 61 liver resections in 60 patients using this technique.

Methods: A retrospective review of 61 procedures in 60 patients using TVE between 1990 and 1997 was carried out.

Medical costs and lost productivity from health conditions at volatile organic compound-contaminated superfund sites.

This paper estimates the health costs at Superfund sites for conditions associated with volatile organic compounds (VOCs) in drinking water. Health conditions were identified from published literature and registry information as occurring at excess rates in VOC-exposed populations. These health conditions were: (1) some categories of birth defects, (2) urinary tract disorders, (3) diabetes, (4) eczema and skin conditions, (5) anemia, (6) speech and hearing impairments in children under 10 years of age, and (7) stroke.

Successful treatment of esophageal achalasia with laparoscopic Heller myotomy and Toupet fundoplication.

Background: Recently, investigators have reported the use of endoscopic myotomy in the treatment of esophageal achalasia. As with the open operation, considerable disagreement exists regarding the appropriate length of the myotomy and the need for a concomitant antireflux procedure.

Methods: Patients presenting with symptomatic achalasia between 1993 and 1997 were included in this prospective study.

Liver transplantation in Ohio.

Background: Since its inception in 1984, the Ohio Solid Organ Transplantation Consortium has tracked liver transplantation outcomes for its five member institutions. Presented herein is a 12-year summary of this data analyzed to determine whether, with increasing experience, outcomes have improved in a cost-effective manner.

Methods: Between July 1984 and June 1996, 1,063 liver transplants were performed in Ohio in 943 patients (772 adults and 171 children), of which 943 were primary and 120 were retransplants (13%).

A randomized clinical trial of ursodeoxycholic acid as adjuvant treatment to prevent liver transplant rejection.

Acute rejection following orthotopic liver transplantation is a common problem despite current immunosuppressive regimens. Ursodeoxycholic acid (UDCA) has been shown in small, open-labeled studies to prevent rejection episodes, although its effects on complications such as infections, length of hospital stay, and survival have not been evaluated. We conducted a randomized, placebo-controlled, double-blind trial to determine if UDCA (10-15 mg/kg/d) added to a cyclosporine-based immunosuppressive regimen was associated with a decrease in the incidence of at least one episode of acute cellular rejection.

Two-way selection for daily gain and feed conversion in a composite rabbit population.

We conducted a two-way selection experiment in a composite rabbit population to investigate the responses to selection for postweaning ADG and feed conversion (FC). Two generations of crossing, followed by four generations of random pair matings, preceded three generations of selection. Selection was practiced within four lines: high-feed conversion (HFC), low-feed conversion (LFC), high gain (HG), and low gain (LG).

Adhesion formation in laparoscopic inguinal hernia repair.

Background: In laparoscopic inguinal hernia repair controversy exists concerning the most appropriate repair method and implant material to use if intraabdominal adhesions are to be minimized.

Methods: In 108 pigs, we implanted three different types of mesh by both the TAPP (transabdominal preperitoneal) and Onlay (prosthesis placed directly upon the peritoneum) methods. Specimens were harvested in three time periods and adhesion formation was compared.

Isolated splenic metastases from colon cancer.

Metastatic tumors of the spleen are rare and usually occur in the presence of disseminated visceral metastases. The liver is the most common site of metastatic spread from colon cancer. We report a case of isolated intrasplenic metastasis from sigmoid colon cancer and review the possible reasons for the rarity of splenic metastasis.

Biodiversity and the productivity and stability of ecosystems.

Attempts to unveil the relationships between the taxonomic diversity, productivity and stability of ecosystems continue to generate inconclusive, contradictory and controversial conclusions. New insights from recent studies support the hypothesis that species diversity enhances productivity and stability in some ecosystems, but not in others. Appreciation is growing for the ways that particular ecosystem features, such as environmental variability and nutrient stress, can influence biotic interactions.

Effects of CO2 pneumoperitoneum in pregnant ewes.

Laparoscopy has been considered a relative contraindication in pregnant patients because the CO2 pneumoperitoneum may cause maternal and/or fetal hypotension, acidosis, hypercarbia, hypoxia, changes in cardiac output, or uterine artery blood flow. These potential changes were studied in an established animal pregnancy model. Twelve gravid ewes (116-120 days gestation) underwent catheterization of maternal femoral artery and vein, fetal hindlimb artery and vein, insertion of a uterine artery flow probe, and pulmonary artery catheter.

Effects of environmental heat and intake of tall fescue seed infested with Acremonium coenophialum on the acid-base status of young bulls.

Effects of high environmental temperature and dietary intake of tall fescue (Festuca arundinacea) seed containing the endophyte Acremonium coenophialum on bovine acid-base status were studied using 3 groups of bull calves (2 Simmental, 1 Angus). Experimental animals were housed in controlled-climate chambers and subjected to gradual increases in environmental temperature, first while being fed an endophyte-free diet and then while being fed a diet containing 17% endophyte-infested fescue seed. Marked acid-base disturbances were not observed in any animals.

The "white clot syndrome" in hepatic transplantation.

Heparin-associated thrombocytopenia and thrombosis (Type II HAT), the "white clot syndrome," has not been previously reported as a cause for fulminant hepatic failure after liver transplantation. Thrombocytopenia and the use of heparin are common events in the newly transplanted patient. A man who was transplanted for sclerosing cholangitis, and re-exposed to heparin, is described with thrombocytopenia, thrombosis of all hepatic vessels, and heparin antibodies.

Heat tolerance in two tropically adapted Bos taurus breeds, Senepol and Romosinuano, compared with Brahman, Angus, and Hereford cattle in Florida.

Two trials were conducted with heifers to determine heat tolerance among temperate Bos taurus (Angus, Hereford), Bos indicus (Brahman), tropical Bos taurus (Senepol, Romosinuano), and the reciprocal crosses of Hereford and Senepol. Differences among breeds in temperament score, circulating concentrations of cortisol, and blood packed cell volume were also investigated. Trial 1 used 43 Angus, 28 Brahman, 12 Hereford, 23 Romosinuano, 16 Senepol, 5 Hereford x Senepol (H x S), and 5 Senepol x Hereford (S x H) heifers.

Monoethylglycinexylidide formation as an independent measure of warm hepatic ischemia and reperfusion injury.

An accurate serologic measure of hepatic function would be clinically useful in selecting donors for liver transplantation. An experimental model that incorporates varying lengths of total hepatic warm ischemia with reperfusion injury was utilized to compare serologic parameters and mitochondrial performance of oxidative phosphorylation in predicting hepatocellular injury. Monoethylglycinexylidide (MEGX) formation following bolus intravenous lidocaine injection was found to be significantly decreased (P < 0.

Prevalence and reversibility of the hepatopulmonary syndrome after liver transplantation. The Cleveland Clinic experience.

To ascertain the prevalence and reversibility of the hepatopulmonary syndrome, we reviewed the cases of 98 patients undergoing liver transplantation at the Cleveland (Ohio) Clinic Foundation from June 1988 through July 1992 and identified 4 patients with clinically recognized hepatopulmonary syndrome (prevalence 4%). All 4 patients ultimately had complete reversal of their disorder. As reviewed herein, the prevalence of the hepatopulmonary syndrome in the current series is lower than in previous reports, possibly reflecting a dependence on its clinical recognition in this series rather than the use of routine screening tests.

Successful laparoscopic repair of paraesophageal hernia.

Objective: To evaluate prospectively the safety and efficacy of laparoscopic surgical techniques in the repair of types II and III paraesophageal hernias.

Design: Case series.

Setting: Tertiary-care, university-affiliated hospitals.

Fifty years of surgery for portal hypertension at the Cleveland Clinic Foundation. Lessons and prospects.

Objective: The 50-year experience with surgery for the treatment of portal hypertension and bleeding varices at the Cleveland Clinic is reviewed.

Summary Background Data: A variety of procedures have been used to treat bleeding varices during the past 50 years. These include transesophageal ligation of varices or devascularization of the esophagus and stomach with splenectomy; portal-systemic (total) shunts; distal splenorenal (selective) shunts; endoscopic sclerotherapy; transjugular intrahepatic portal-systemic shunts; and liver transplantation.