mTORC2 is an important signaling intermediary in VEGF-mediated endothelial cell proliferation, survival and migration

Objective: The vascular endothelial growth factor (VEGF) is a prominent¦contributor of tumor angiogenesis. VEGF induces endothelial cell migration,¦proliferation and survival, which are critical steps for the development of new¦blood vessels, through the activation of the Mek/Erk and PI3K/Akt signaling¦pathways. Recent findings have demonstrated that mTORC2 regulates Akt and¦Erk in endothelial cells. The role of mTORC2 in VEGF-mediated endothelial¦cell responses has however not been characterized.¦Methods: We used human umbilical vein endothelial cells (HUVEC). The¦effects of VEGF on the Mek/Erk and PI3K/Akt pathway were analyzed by¦Western blot. Inhibition of mTORC2 was achieved using small interfering¦RNAs to rictor. Cell proliferation rate was assessed by BrdU incorporation and¦immunocytofluorescence. Apoptosis rate was determined by ELISA as well as¦propidium iodine staining and FACS analysis. Migration of endothelial cells¦was evaluated using a modified Boyden chamber assay.¦Results:Wefound thatVEGF activatesmTORC2 in endothelial cells. Indeed,¦treatment of endothelial cells with VEGF increases Akt phosphorylation, a¦downstream effector of mTORC2. We have further determined the role¦of mTORC2 in VEGF signaling by knocking down rictor, a component¦of mTORC2. We observed that VEGF failed to activate Akt and Erk in¦endothelial cells transfected with rictor siRNA. To next analyze the functional¦significance of mTORC2 inhibition on VEGF-mediated endothelial cell¦responses we performed proliferation, survival and migration assays. We found¦that VEGF failed to induce endothelial cell proliferation, survival and migration¦in endothelial cell lacking mTORC2 activity.¦Conclusion: These results show that mTORC2 is an important signaling¦intermediary in VEGF-induced endothelial cell responses and thus represents¦an interesting target to block VEGF-induced angiogenesis.

Oligonucleotide-polyethylenimine complexes targeting retinal cells: structural analysis and application to anti-TGFbeta-2 therapy.

PURPOSE: The aim of this study was to characterize oligonucleotide-polyethylenimine (ODN/PEI) complex preparation for potential transfection of retinal cells in vitro and in vivo. METHODS: The effect of medium preparation [HEPES-buffered saline (HBS), water] on particle size and morphology was evaluated. Cultured Lewis rat retinal Müller glial (RMG) cells were transfected using fluorescein isothiocyanate (FITC)-ODN/PEI complexes specifically directed at transforming growth factor beta (TGFbeta)-2. Efficacy of transfection was evaluated using confocal microscopy, and regulation of gene expression was assayed using quantitative real-time RT-PCR and ELISA assay. One, 24, and 72 h after injection of FITC-ODN/PEI complexes into the vitreous of rat eyes, their distribution was analyzed on eye sections. RESULTS: Complexes prepared in HBS were smaller than complexes prepared in pure water and presented a core-shell structure. These particles showed a high cellular internalization efficacy, along with a significant and specific down-regulation of TGFbeta-2 expression and production in RMG cells, correlating with specific inhibition of cell growth at 72 h. In vivo, complexes efficiently transfect retinal cells and follow a transretinal migration at 24 h. After 72 h, ODN seems to preferentially target RMG cells without inducing any detectable toxicity. CONCLUSIONS: Specific down-regulation of TGFbeta-2 expression using ODN/PEI complexes may have potential interest for the treatment of retinal diseases associated with glial proliferation.

First principles analysis of the stability and diffusion of oxygen vacancies in meetal oxides

Oxygen vacancies in metal oxides are known to determine their chemistry and physics. The properties of neutral oxygen vacancies in metal oxides of increasing complexity (MgO, CaO, alpha-Al2O3, and ZnO) have been studied using density functional theory. Vacancy formation energies, vacancy-vacancy interaction, and the barriers for vacancy migration are determined and rationalized in terms of the ionicity, the Madelung potential, and lattice relaxation. It is found that the Madelung potential controls the oxygen vacancy properties of highly ionic oxides whereas a more complex picture arises for covalent ZnO.

Migration of antimony from polyethylene terephthalate used in mineral water bottles.

The influence of storage time and temperature on Sb migration from PET bottles into mineral water was studied in short-term tests lasting up to 15 days and long-term studies lasting up to 220 days. Samples purchased were stored in three different coloured bottles: clear (CL), light blue (LB) and dark blue (DB). Sb migration was assayed by HG-AFS for total determination and HPLC-ICP-MS for speciation analysis. Migration studies showed that waters stored at 4 and 20 oC were not subject to Sb migration. At 40 oC there was a significant increase in Sb concentration, although the maximum limit established by the European Union (5.0 ug/L) was not exceeded, whereas at 60 oC samples were subject to considerable Sb migration after 30 days of storage. In this case, the maximum limit established by the European Union was exceeded and both Sb (V) and Sb (III) were detected.

Migration and horizontal gene transfer divide microbial genomes into multiple niches.

Horizontal gene transfer is central to microbial evolution, because it enables genetic regions to spread horizontally through diverse communities. However, how gene transfer exerts such a strong effect is not understood. Here we develop an eco-evolutionary model and show how genetic transfer, even when rare, can transform the evolution and ecology of microbes. We recapitulate existing models, which suggest that asexual reproduction will overpower horizontal transfer and greatly limit its effects. We then show that allowing immigration completely changes these predictions. With migration, the rates and impacts of horizontal transfer are greatly increased, and transfer is most frequent for loci under positive natural selection. Our analysis explains how ecologically important loci can sweep through competing strains and species. In this way, microbial genomes can evolve to become ecologically diverse where different genomic regions encode for partially overlapping, but distinct, ecologies. Under these conditions ecological species do not exist, because genes, not species, inhabit niches.

Systematic review with meta-analysis: self-expanding metal stents in patients with cirrhosis and severe or refractory oesophageal variceal bleeding.

BACKGROUND: The prognosis of patients with cirrhosis and acute variceal bleeding is very poor when the standard-of-care fails to control bleeding. New treatment modalities are needed in these patients. AIM: To synthesise the available evidence on the efficacy of self-expanding metal stents (SEMS) in patients with cirrhosis and severe or refractory oesophageal variceal bleeding. METHODS: Meta-analysis of trials evaluating SEMS in patients with cirrhosis and severe or refractory oesophageal variceal bleeding. RESULTS: Thirteen studies were included. The pooled estimate rates were 0.40 (95% confidence interval, CI = 0.31-0.49) for death, 0.41 (95% CI = 0.29-0.53) for liver-related death and 0.36 (95% CI = 0.26-0.47) for death at day 30, with low heterogeneity between studies. The pooled estimate rates were 0.12 (95% CI = 0.07-0.21) for mortality related to variceal bleeding, and 0.18 (95% CI = 0.11-0.29) for failure to control bleeding with SEMS, with no or low heterogeneity between studies. The pooled estimate rate were 0.16 (95% CI = 0.04-0.48) for rebleeding after stent removal and 0.28 (95% CI = 0.17-0.43) for stent migration, with high heterogeneity. A significant proportion of patients had access to liver transplantation or to TIPSS [pooled estimate rate 0.10 (95% CI = 0.04-0.21) and 0.26 (95% CI = 0.18-0.36), respectively]. CONCLUSIONS: Fewer than 40% of patients treated with SEMS were dead at 1 month. SEMS can be used as a bridge to TIPSS or to liver transplantation in a significant proportion of patients. Additional studies are required to identify potential risk factors leading to a poor prognosis in patients with acute variceal bleeding in whom the use of SEMS could be considered.

Health Migration Policies and Ethical Controversies: the Case of African Nurses in the UK

The United Kingdom (UK) for last few decades has been faced with a growing need for health personnel and has therefore attracted professionals, particularly overseas nurses. The country has been characterised by a historical migration policy favourable to the recruitment of foreign health staff. However, in the context of deep shortage and high level of diseases and health system weakness, the international health professional recruitment from Sub Saharan Africa has created unprecedented ethical controversies which have pushed the UK to the centre of discussions because of its liberal policies towards international recruitment that have been considered as aggressive. While the 'brain drain' controversy is well known, less attention has been devoted to the specific international health migration controversy and the pivotal role of the UK in the diffusion of ethical code of practice. Using mainly the perspective of the policy analysis of controversy (Roe 1994) and the analysis of discourses (de Haas 2008), our paper comes back respectively to the nature of the controversy and the pivotal role of the UK. It also analyses how the implementation of UK ethical policies - Code of Practice, banned countries list of recruitment, restrictive immigration policies - have been considered as inefficient and unethical in their contents and their targets.

Combining stable isotope analyses and geolocation to reveal kittiwake migration

Determining migratory strategies of seabirds is still a major challenge due to their relative inaccessibility. Small geolocators are improving this knowledge, but not all birds can be tracked. Stable isotope ratios in feathers can help us to understand migration, but we still have insufficient baseline knowledge for linking feather signatures to movements amongst distinct water masses. To understand the migration strategies of kittiwakes Rissa tridactyla and the link between stable isotopes in feathers and the areas in which these were grown, we tracked 6 kittiwakes from Hornøya, Norway, with light level geolocators over 1 yr. Then we analysed the stable isotopes of carbon and nitrogen in their 1st and 7th primary feathers as well as in the 1st, 3rd, 5th, 7th and 10th primaries of 12 birds found freshly dead in the same breeding colony. After breeding, all tracked birds moved east of the Svalbard Archipelago and subsequently migrated to the Labrador Sea. Thereafter, birds showed individual variation in migration strategies: 3 travelled to the NE Atlantic, whereas the others remained in the Labrador Sea until the end of the wintering period. Changes in stable isotope signatures from the 1st to the 10th primary feathers corresponded well to the sequence of movements during migration and the area in which we inferred that each feather was grown. Thus, by combining information on moult patterns and tracking data, we demonstrate that stable isotope analysis of feathers can be used to trace migratory movements of seabirds.

The Use of Radiostereometric Analysis in Fractures of the Distal Radius: From Phantom Models to Clinical Application

Radiostereometric analysis (RSA) is a highly accurate method for the measurement of in vivo micromotion of orthopaedic implants. Validation of the RSA method is a prerequisite for performing clinical RSA studies. Only a limited number of studies have utilised the RSA method in the evaluation of migration and inducible micromotion during fracture healing. Volar plate fixation of distal radial fractures has increased in popularity. There is still very little prospective randomised evidence supporting the use of these implants over other treatments. The aim of this study was to investigate the precision, accuracy, and feasibility of using RSA in the evaluation of healing in distal radius fractures treated with a volar fixed-angle plate. A physical phantom model was used to validate the RSA method for simple distal radius fractures. A computer simulation model was then used to validate the RSA method for more complex interfragmentary motion in intra-articular fractures. A separate pre-clinical investigation was performed in order to evaluate the possibility of using novel resorbable markers for RSA. Based on the validation studies, a prospective RSA cohort study of fifteen patients with plated AO type-C distal radius fractures with a 1-year follow-up was performed. RSA was shown to be highly accurate and precise in the measurement of fracture micromotion using both physical and computer simulated models of distal radius fractures. Resorbable RSA markers demonstrated potential for use in RSA. The RSA method was found to have a high clinical precision. The fractures underwent significant translational and rotational migration during the first two weeks after surgery, but not thereafter. Maximal grip caused significant translational and rotational interfragmentary micromotion. This inducible micromotion was detectable up to eighteen weeks, even after the achievement of radiographic union. The application of RSA in the measurement of fracture fragment migration and inducible interfragmentary micromotion in AO type-C distal radius fractures is feasible but technically demanding. RSA may be a unique tool in defining the progress of fracture union.

Enterprise applications migration to the cloud: risks and opportunities

Millions of enterprises move their applications to a cloud every year. According to Forrester Research “the global cloud computing market will grow from a $40.7 billion in 2011 to $241 billion in 2020”. Due to increased interests and demand broad range of providers and solutions have appeared in the market. It is vital to be able to predict possible problems correctly and to classify and mitigate risks associated with the migration process. The study will show the main criteria that should be taken into consideration while making decision of moving enterprise applications to the cloud and choosing appropriate vendor. The main goal of the research is to identify main problems during the migration to a cloud and propose a solution for their prevention and mitigation of consequences in case of occurrence. The research provides an overview of existing cloud solutions and deployment models for enterprise applications. It identifies decision drivers of an applications migration to a cloud and potential risks and benefits associated with this. Finally, the best practices for the successful enterprise-to-cloud migration based on the case studies analysis are formulated.

Analysis of hematologic and serum chemistry values of Spheniscus magellanicus with molecular detection of avian malarial parasites (Plasmodium spp.)

Magellanic penguins (Spheniscus magellanicus) routinely migrate from their breeding colonies to Southern Brazil often contracting diseases during this migration, notably avian malaria, which has been already reported in Brazil and throughout the world. Detection of Plasmodium spp. in blood smears is the routine diagnostic method of avian malaria, however it has a low sensitivity rate when compared to molecular methods. Considering the negative impact of avian malaria on penguins, the aim of this study was to detect the presence of Plasmodium spp. in Magellanic penguins using Polymerase Chain Reaction (PCR) and by verifying clinical, hematological, and biochemical alterations in blood samples as well as to verify the likely prognosis in response to infection. Blood samples were obtained from 75 penguins to determine packed cell volume (PCV), red blood cell (RBC) and white blood cell (WBC) counts, mean corpuscular volume (MCV), uric acid, total protein, albumin, globulin and aspartate aminotransferase (AST) activity levels. Whole blood samples were used for PCR assays. Plasmodium spp. was detected in 32.0% of the specimens using PCR and in 29.3% using microscopic analyses. Anorexia, diarrhea and neurological disorders were more frequent in penguins with malaria and a significant weight difference between infected and non-infected penguins was detected. PCV and MCV rates showed no significant difference. RBC and WBC counts were lower in animals with avian malaria and leukopenia was present in some penguins. Basophil and lymphocyte counts were lower in infected penguins along with high monocyte counts. There was no significant difference in AST activities between infected and non-infected animals. There was a significant increase in uric acid values, however a decrease in albumin values was observed in infected penguins. Based on this study, we concluded that Plasmodium spp. occurs in Magellanic penguins of rehabilitation centers in Southeastern Brazil, compromising the weight of infected animals with clinical alterations appearing in severe cases of this disease. It was also noted that, although the hematological abnormalities presented by these animals may not have been conclusive, leukopenia, monocytosis and the decrease of basophils and lymphocytes revealed an unfavorable prognosis, and Plasmodium spp. infections may progress with elevated uric acid concentration and low albumin levels.

Distributed document migration between ERP systems by means of messaging and event sourcing

This bachelor’s thesis, written for Lappeenranta University of Technology and implemented in a medium-sized enterprise (SME), examines a distributed document migration system. The system was created to migrate a large number of electronic documents, along with their metadata, from one document management system to another, so as to enable a rapid switchover of an enterprise resource planning systems inside the company. The paper examines, through theoretical analysis, messaging as a possible enabler of distributing applications and how it naturally fits an event based model, whereby system transitions and states are expressed through recorded behaviours. This is put into practice by analysing the implemented migration systems and how the core components, MassTransit, RabbitMQ and MongoDB, were orchestrated together to realize such a system. As a result, the paper presents an architecture for a scalable and distributed system that could migrate hundreds of thousands of documents over weekend, serving its goals in enabling a rapid system switchover.

Hb Köln [a2b298(FG5) val-met] identified by DNA analysis in a Brazilian family

Hb Köln was identified by DNA analysis in a Brazilian patient. A four-year old Brazilian female, with jaundice since birth, presented an abnormal band, between A2 and S, in hemoglobin electrophoresis on a cellulose acetate membrane, and a band with electrophoretic migration similar to Hb C on agar gel. Thermic instability and isopropanol precipitation tests were positive. Heinz bodies were observed in the patient’s peripheral blood. Sequencing of the three exons of the b globin gene detected a transition from G to A in the first position of codon 98. This alteration does not create or abolish any known restriction site. In this case, confirmation of the mutation was accomplished by allele-specific oligonucleotide hybridization, which is a simple and fast identification method when the clinical data and hematological and electrophoretic patterns are suggestive of Hb Köln.

Alternagin-C, a disintegrin-like protein from the venom of Bothrops alternatus, modulates alpha2ß1 integrin-mediated cell adhesion, migration and proliferation

The alpha2ß1 integrin is a major collagen receptor that plays an essential role in the adhesion of normal and tumor cells to the extracellular matrix. Alternagin-C (ALT-C), a disintegrin-like protein purified from the venom of the Brazilian snake Bothrops alternatus, competitively interacts with the alpha2ß1 integrin, thereby inhibiting collagen binding. When immobilized in plate wells, ALT-C supports the adhesion of fibroblasts as well as of human vein endothelial cells (HUVEC) and does not detach cells previously bound to collagen I. ALT-C is a strong inducer of HUVEC proliferation in vitro. Gene expression analysis was done using an Affimetrix HU-95A probe array with probe sets of ~10,000 human genes. In human fibroblasts growing on collagen-coated plates, ALT-C up-regulates the expression of several growth factors including vascular endothelial growth factor, as well as some cell cycle control genes. Up-regulation of the vascular endothelial growth factor gene and other growth factors could explain the positive effect on HUVEC proliferation. ALT-C also strongly activates protein kinase B phosphorylation, a signaling event involved in endothelial cell survival and angiogenesis. In human neutrophils, ALT-C has a potent chemotactic effect modulated by the intracellular signaling cascade characteristic of integrin-activated pathways. Thus, ALT-C acts as a survival factor, promoting adhesion, migration and endothelial cell proliferation after binding to alpha2ß1 integrin on the cell surface. The biological activities of ALT-C may be helpful as a therapeutic strategy in tissue regeneration as well as in the design of new therapeutic agents targeting alpha2ß1 integrin.

Analytical modelling of bacterial migration and accumulation with rate-limited sorption in discrete fractures

An analytical model for bacterial accumulation in a discrete fractllre has been developed. The transport and accumlllation processes incorporate into the model include advection, dispersion, rate-limited adsorption, rate-limited desorption, irreversible adsorption, attachment, detachment, growth and first order decay botl1 in sorbed and aqueous phases. An analytical solution in Laplace space is derived and nlln1erically inverted. The model is implemented in the code BIOFRAC vvhich is written in Fortran 99. The model is derived for two phases, Phase I, where adsorption-desorption are dominant, and Phase II, where attachment-detachment are dominant. Phase I ends yvhen enollgh bacteria to fully cover the substratllm have accllillulated. The model for Phase I vvas verified by comparing to the Ogata-Banks solution and the model for Phase II was verified by comparing to a nonHomogenous version of the Ogata-Banks solution. After verification, a sensitiv"ity analysis on the inpllt parameters was performed. The sensitivity analysis was condllcted by varying one inpllt parameter vvhile all others were fixed and observing the impact on the shape of the clirve describing bacterial concentration verSllS time. Increasing fracture apertllre allovvs more transport and thus more accllffilliation, "Vvhich diminishes the dllration of Phase I. The larger the bacteria size, the faster the sllbstratum will be covered. Increasing adsorption rate, was observed to increase the dllration of Phase I. Contrary to the aSSllmption ofllniform biofilm thickness, the accllffilliation starts frOll1 the inlet, and the bacterial concentration in aqlleous phase moving towards the olitiet declines, sloyving the accumulation at the outlet. Increasing the desorption rate, redllces the dliration of Phase I, speeding IIp the accllmlilation. It was also observed that Phase II is of longer duration than Phase I. Increasing the attachment rate lengthens the accliffililation period. High rates of detachment speeds up the transport. The grovvth and decay rates have no significant effect on transport, althollgh increases the concentrations in both aqueous and sorbed phases are observed. Irreversible adsorption can stop accllillulation completely if the vallIes are high.