Current and desired organizational culture of the financial system of the province of Huancayo, Peru

The objective of this investigation was to identify the current organizational culture of the financial system of the province of Huancayo and the culture that they wanted, to serve as a complement to the traditional indicators of the sector. The Organizational Cul- ture Assessment Instrument (OCAI) was practiced on 412 workers from 16 financial in- stitutions. It is a quantitative, non-experimental and descriptive study

Extramitochondrial OPA1 and adrenocortical function

We have previously described that silencing of the mitochondrial protein OPA1 enhances mitochondrial 27 Ca2+ signaling and aldosterone production in H295R adrenocortical cells. Since extramitochondrial OPA1 28 (emOPA1) was reported to facilitate cAMP-induced lipolysis, we hypothesized that emOPA1, via the 29 enhanced hydrolysis of cholesterol esters, augments aldosterone production in H295R cells. A few 30 OPA1 immunopositive spots were detected in �40% of the cells. In cell fractionation studies OPA1/COX 31 IV (mitochondrial marker) ratio in the post-mitochondrial fractions was an order of magnitude higher 32 than that in the mitochondrial fraction. The ratio of long to short OPA1 isoforms was lower in post-mito- 33 chondrial than in mitochondrial fractions. Knockdown of OPA1 failed to reduce db-cAMP-induced phos- 34 phorylation of hormone-sensitive lipase (HSL), Ca2+ signaling and aldosterone secretion. In conclusion, 35 OPA1 could be detected in the post-mitochondrial fractions, nevertheless, OPA1 did not interfere with 36 the cAMP – PKA – HSL mediated activation of aldosterone secretio

Use of pooled serum samples to assess herd disease status using commercially available ELISAs

Pooled samples are used in veterinary and human medicine as a cost-effective approach to monitor disease prevalence. Nonetheless, there is limited information on the effect of pooling on test performance, and research is required to determine the appropriate number of samples which can be pooled. Therefore, this study aimed to evaluate the use of pooled serum samples as a herd-level surveillance tool for infectious production-limiting diseases: bovine viral diarrhoea (BVD), infectious bovine rhinotracheitis (IBR), enzootic bovine leukosis (EBL) and Neospora caninum (NC), by investigating the maximum number of samples one can pool to identify one positive animal, using commercial antibody-detection ELISAs. Four positive field standards (PFS), one for each disease, were prepared by pooling highly positive herd-level samples diagnosed using commercially available ELISA tests. These PFS were used to simulate 18 pooled samples ranging from undiluted PFS to a dilution representing 1 positive in 1,000 animals using phosphate-buffered saline as diluent. A 1:10 dilution of the PFS resulted in positive results for IBR, BVD and EBL. Moreover, for IBR and BVD, results were still positive at 1:100 and 1:30 dilutions, respectively. However, for NC, a lower dilution (8:10) was required for a seropositive result. This study indicates that, at herd-level, the use of pooled serum is a useful strategy for monitoring infectious diseases (BVD, IBR and EBL) but not NC, using readily available diagnostic assays

One-dimensional oxide nanostructures : growth, applications and devices

One dimensional (1D) inorganic materials are gaining high attention due to their structural stability and unique structural fatures. Among them, oxides are widely studied due to their well established application potential and mechanical as well as chemical stability. We have developed a generic approach for size-selective and site-specific growth of oxide nanowires by combination of a catalyst assisted growth mechanism and a molecular precursor approach, which is a viable alternative to other gas phase and solution procedures and produces well-defined (morphology and composition) materials

Syndecans Reside in Sphingomyelin-Enriched Low-Density Fractions of the Plasma Membrane Isolated from a Parathyroid Cell Line

BACKGROUND: Heparan sulfate proteoglycans (HSPGs) are one of the basic constituents of plasma membranes. Specific molecular interactions between HSPGs and a number of extracellular ligands have been reported. Mechanisms involved in controlling the localization and abundance of HSPG on specific domains on the cell surface, such as membrane rafts, could play important regulatory roles in signal transduction. METHODOLOGY/PRINCIPAL FINDINGS: Using metabolic radiolabeling and sucrose-density gradient ultracentrifugation techniques, we identified [(35)S]sulfate-labeled macromolecules associated with detergent-resistant membranes (DRMs) isolated from a rat parathyroid cell line. DRM fractions showed high specific radioactivity ([(35)S]sulfate/mg protein), implying the specific recruitment of HSPGs to the membrane rafts. Identity of DRM-associated [(35)S]sulfate-labeled molecules as HSPGs was confirmed by Western blotting with antibodies that recognize heparan sulfate (HS)-derived epitope. Analyses of core proteins by SDS-PAGE revealed bands with an apparent MW of syndecan-4 (30-33 kDa) and syndecan-1 (70 kDa) suggesting the presence of rafts with various HSPG species. DRM fractions enriched with HSPGs were characterized by high sphingomyelin content and found to only partially overlap with the fractions enriched in ganglioside GM1. HSPGs could be also detected in DRMs even after prior treatment of cells with heparitinase. CONCLUSIONS/SIGNIFICANCE: Both syndecan-1 and syndecan-4 have been found to specifically associate with membrane rafts and their association seemed independent of intact HS chains. Membrane rafts in which HSPGs reside were also enriched with sphingomyelin, suggesting their possible involvement in FGF signaling. Further studies, involving proteomic characterization of membrane domains containing HSPGs might improve our knowledge on the nature of HSPG-ligand interactions and their role in different signaling platforms

Studies on the antiatherogenic properties of liposomes

There has been a wealth of prior literature demonstrating that the infusion of phospholipid causes the reversal of experimentally induced atherosclerosis in animals. However, the development of liposomal therapies to manage atherosclerosis is only now being considered seriously. The studies presented in this thesis were aimed at confirming the antiatherogenic properties of phospholipid using a pharmaceutically acceptable formulation of liposomes capable of pre-clinical development. The work can be divided into three main areas of investigation. In order to test the capacity of liposomes to act as a "sink" for cholesterol, the relative rates of movement of sterol were measured between leaflets and between vesicles. The kinetics of movement of cholesterol and cholesterol sulphate (CS) between vesicles were studied using donor vesicles of various size ranging from 40-250 nm, composed of egg phosphatidylcholine (EPC)/Sterol/N-palmitoyl dihydrolactosylcerebroside (75:10:15 mol ratio). Trace amounts of [³H]-sterol in donor vesicles was used to monitor sterol transfer into a 10 fold excess of EPC large unilamellar vesicles (LUV) of 100 nm diameter. Following the addition of a lectin, the two populations of vesicles were separated by centrifugation. The rate constants for efflux and transbilayer diffusion for both sterol molecules were determined after fitting kinetic data to a three compartment model. The rate of intermembrane exchange for CS was considerably faster than for cholesterol in all liposomes tested. Using the kinetic model, a rate of transbilayer movement for cholesterol and CS was estimated. In both cases, it was found to be slower than the rate of efflux from the surface of vesicles. The results from this chapter suggest that the greatest rate of cholesterol uptake in vivo should be achieved using unilamellar vesicles with greatest surface area and the smallest diameter. The second group of studies examined the capacity of different liposomal preparations (as studied in chapter two), to mobilize cholesterol in vivo. This involved measuring the ability of liposomes to increase plasma cholesterol concentrations in mice. Surprisingly, LUV, composed of EPC, were found to be approximately twice as effective at mobilizing cholesterol than small unilamellar vesicles (SUV) of the same composition. This is because the increase in plasma cholesterol is proportional to the residence time of vesicles in the circulation. LUV with a diameter of approximately 100 nm, accumulate the most sterol during 24 h in the animal model tested here. Vesicles composed of phospholipid in a gel state at physiological temperatures, gave rise to a smaller increase in plasma cholesterol compared to liquidcrystalline vesicles. A significant decrease in the ratio of cholesterol-to-phospholipid in the lipoprotein pool was observed following liposome infusion, whereas cholesterol levels and turnover in erythrocytes remained constant. These results indicate that net transfer of cholesterol into liposomes in vivo occurs more extensively from the lipoprotein cholesterol pool than from the erythrocyte cell membrane pool. This is consistent with the hypothesis of Williams et al. (1984) that liposomes enhance reverse cholesterol transport by generating cholesterol-poor HDL particles that can extravasate and promote more sterol efflux from peripheral tissues. In the final groups of studies presented here, the antiatherogenic properties of EPC LUV of 100 nm diameter were tested in an experimental model for atherosclerosis in which rabbits were fed a diet rich in cholesterol. Forty eight rabbits were divided into two diet groups fed standard rabbit chow or fed a diet enriched in cholesterol (0.5% by weight) to induce the formation of atherosclerotic plaques. Prior to the initiation of phospholipid therapy, the cholesterol diet was ceased and all animals were returned to standard rabbit chow. The treatment protocol involved a total of 10 bolus injections of vesicles at a phospholipid dose of 300 mg/kg or an equivalent volume of saline, with one injection given to each animal every 10 days. Liposomal injections brought about a large movement of cholesterol into the blood pool and resulted in a significant reduction in the cholesterol content of aortas as well as the degree of surface plaque involvement in atherosclerotic animals. Most notably, the thoracic aorta exhibited a 48% reduction in tissue cholesterol content per gram of protein compared to tissue from saline-treated controls. Histochemical analyses revealed that aortas from animals receiving the repeated infusions of phospholipid, displayed less cholesterol deposits in lesions, and a moderate reduction in the ratio of intimal/medial thickness. This liposome-mediated regression of atheroma was observed despite persistent elevation of plasma cholesterol levels after removal of the animals from the high cholesterol diet. These results support previous observations and suggest that phospholipid infusion may indeed be a useful therapy in the management of atherosclerosis.Medicine, Faculty ofBiochemistry and Molecular Biology, Department ofGraduat