216 research outputs found

    mtDNA lineage analysis of mouse L-cell lines reveals the accumulation of multiple mtDNA mutants and intermolecular recombination

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    The role of mitochondrial DNA (mtDNA) mutations and mtDNA recombination in cancer cell proliferation and developmental biology remains controversial. While analyzing the mtDNAs of several mouse L cell lines, we discovered that every cell line harbored multiple mtDNA mutants. These included four missense mutations, two frameshift mutations, and one tRNA homopolymer expansion. The LA9 cell lines lacked wild-type mtDNAs but harbored a heteroplasmic mixture of mtDNAs, each with a different combination of these variants. We isolated each of the mtDNAs in a separate cybrid cell line. This permitted determination of the linkage phase of each mtDNA and its physiological characteristics. All of the polypeptide mutations inhibited their oxidative phosphorylation (OXPHOS) complexes. However, they also increased mitochondrial reactive oxygen species (ROS) production, and the level of ROS production was proportional to the cellular proliferation rate. By comparing the mtDNA haplotypes of the different cell lines, we were able to reconstruct the mtDNA mutational history of the L-L929 cell line. This revealed that every heteroplasmic L-cell line harbored a mtDNA that had been generated by intracellular mtDNA homologous recombination. Therefore, deleterious mtDNA mutations that increase ROS production can provide a proliferative advantage to cancer or stem cells, and optimal combinations of mutant loci can be generated through recombination

    A Low Cost Real Time Embedded Control System Design Using Infrared Signal Processing with Application to Vehicle Accident Prevention

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    Vehicle accidents are most common if the driving is inadequate. These happen on most factors if the driver is drowsy or if heis alcoholic. Driver drowsiness is recognized as an important factor in the vehicle accidents. It was demonstrated that drivingperformance deteriorates with increased drowsiness with resulting crashes constituting more than 20% of all vehicleaccidents. But the life lost once cannot be re-winded. Advanced technology offers some hope avoid these up to some extent.A car simulator study was designed to collect physiological data for validation of this technology. Methodology for analysisof physiological data, independent assessment of driver drowsiness and development of drowsiness detection algorithm bymeans of sequential fitting and selection of regression models is presented. In this paper proposes an approach towardsdesign of a Low cost real time embedded control system which involves measure and controls the eye blink using sensor. Ascar manufacturers / industrial automotive communities, incorporate intelligent vehicle systems in order to satisfy theconsumer’s ever increasing demand for more assistant systems for comfort, navigation, or communication, to address theissue of increased level of cognitive stress on drivers to the sources of distraction from the most basic task at hand, i.e.,driving the vehicle. Driver’s drowsiness detection systems are actually receiving a large interest in the academic andindustrial automotive communities for their potentiality to reduce fatalities Eye detection is a crucial aspect in many usefulapplications ranging from face recognition / detection to human computer interface for, driver behavior analysis. Visionbaseddriver fatigue detection which is non-contact has a key advantage over applicability. In this paper proposes a simpleand economical prototype design as a solution in developing a intelligent vehicles based on IR signal processing formonitoring the driver’s drowsiness level, vigilance and alerting the driver to prevent accidents. This approach is economicaland all the lower income side vehicle owners can afford to installation of this system.Keywords- Intelligent Vehicles, Driver Vigilance, Human fatigue, Safe Navigatio

    Tensile Properties of Martensitic Stainless Steels at Elevated Temperatures

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    Tensile properties of quenched and tempered martensitic alloys EP-823, HT-9, and 422 were evaluated at temperatures ranging from ambient to 600 °C as a function of three different tempering times. The results indicated that the yield strength, ultimate tensile strength, and the failure strength were gradually reduced with increasing temperature. The ductility parameters were enhanced at elevated temperatures due to increased plastic flow. However, the tempering time did not significantly influence these properties. The evaluation of the fracture surfaces by scanning electron microscopy revealed reduced cracking and dimpled microstructures, indicating enhanced ductility at higher testing temperatures

    Discovery of FNDR-20123, a histone deacetylase inhibitor for the treatment of Plasmodium falciparum malaria

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    BACKGROUND: Emergence of anti-malarial drug resistance and perpetual increase in malaria incidence necessitates the development of novel anti-malarials. Histone deacetylases (HDAC) has been shown to be a promising target for malaria, despite this, there are no HDAC inhibitors in clinical trials for malaria treatment. This can be attributed to the poor pharmacokinetics, bioavailability and selectivity of the HDAC inhibitors. METHODS: A collection of HDAC inhibitors were screened for anti-malarial activity, and the best candidate was profiled in parasite-killing kinetics, growth inhibition of sensitive and multi-drug resistant (MDR) strains and against gametocytes. Absorption, distribution, metabolism and excretion pharmacokinetics (ADME-PK) parameters of FNDR-20123 were determined, and in vivo efficacy was studied in a mouse model for Plasmodium falciparum infection. RESULTS: A compound library of HDAC inhibitors (180 in number) was screened for anti-malarial activity, of which FNDR-20123 was the most potent candidate. The compound had been shown to inhibit Plasmodium HDAC with IC50 of 31 nM and human HDAC with IC50 of 3 nM. The IC50 obtained for P. falciparum in asexual blood-stage assay was 42 nM. When compared to atovaquone and pyrimethamine, the killing profiles of FNDR-20123 were better than atovaquone and comparable to pyrimethamine. The IC50 values for the growth inhibition of sensitive and MDR strains were similar, indicating that there is no cross-resistance and a low risk of resistance development. The selected compound was also active against gametocytes, indicating a potential for transmission control: IC50 values being 190 nM for male and > 5 microM for female gametocytes. FNDR-20123 is a stable candidate in human/mouse/rat liver microsomes (> 75% remaining post 2-h incubation), exhibits low plasma protein binding (57% in humans) with no human Ether-a-go-go-Related Gene (hERG) liability (> 100 microM), and does not inhibit any of the cytochrome P450 (CYP) isoforms tested (IC50 > 25 microM). It also shows negligible cytotoxicity to HepG-2 and THP-1 cell lines. The oral pharmacokinetics in rats at 100 mg/kg body weight shows good exposures (Cmax = 1.1 microM) and half-life (T1/2 = 5.5 h). Furthermore, a 14-day toxicokinetic study at 100 mg/kg daily dose did not show any abnormality in body weight or gross organ pathology. FNDR-20123 is also able to reduce parasitaemia significantly in a mouse model for P. falciparum infection when dosed orally and subcutaneously. CONCLUSION: FNDR-20123 may be a suitable candidate for the treatment of malaria, which can be further developed

    Optimal Don’t Care Filling for Minimizing Peak Toggles During At-Speed Stuck-At Testing

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    Due to the increase in manufacturing/environmental uncertainties in the nanometer regime, testing digital chips under different operating conditions becomes mandatory. Traditionally, stuck-at tests were applied at slow speed to detect structural defects and transition fault tests were applied at-speed to detect delay defects. Recently, it was shown that certain cell-internal defects can only be detected using at-speed stuck-at testing. Stuck-at test patterns are power hungry, thereby causing excessive voltage droop on the power grid, delaying the test response, and finally leading to false delay failures on the tester. This motivates the need for peak power minimization during at-speed stuck-at testing. In this article, we use input toggle minimization as a means to minimize a circuit’s power dissipation during at-speed stuck-at testing under the Combinational State Preservation scan (CSP-scan) Design-For-Testability (DFT) scheme. For circuits whose test sets are dominated by don’t cares, this article maps the problem of optimal X-filling for peak input toggle minimization to a variant of the interval coloring problem and proposes a Dynamic Programming (DP) algorithm (DP-fill) for the same along with a theoretical proof for its optimality. For circuits whose test sets are not dominated by don’t cares, we propose a max scatter Hamiltonian path algorithm, which ensures that the ordering is done such that the don’t cares are evenly distributed in the final ordering of test cubes, thereby leading to better input toggle savings than DP-fill. The proposed algorithms, when experimented on ITC99 benchmarks, produced peak power savings of up to 48% over the best-known algorithms in literature. We have also pruned the solutions thus obtained using Greedy and Simulated Annealing strategies with iterative 1-bit neighborhood to validate our idea of optimal input toggle minimization as an effective technique for minimizing peak power dissipation during at-speed stuck-at testing

    Mitochondrial dysfunction in CA1 hippocampal neurons of the UBE3A deficient mouse model for Angelman syndrome

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    Angelman syndrome (AS) is a severe neurological disorder caused by a deficiency of ubiquitin protein ligase E3A (UBE3A), but the pathophysiology of the disease remains unknown. We now report that in the brains of AS mice in which the maternal UBE3A allele is mutated (m-) and the paternal allele is potentially inactivated by imprinting (p+) (UBE3A m-p+), the mitochondria are abnormal and exhibit a partial oxidative phosphorylation (OXPHOS) defect. Electron microscopy of the hippocampal region of the UBE3A m-p+ mice (n=6) reveals small, dense mitochondria with altered cristae, relative to wild-type littermates (n=6) and reduced synaptic vesicle density. The specific activity of OXPHOS complex III is reduced in whole brain mitochondria in UBE3A m-p+ (n=5) mice versus wild-type littermates (n=5). Therefore, mitochondrial dysfunction may contribute to the pathophysiology of Angelman syndrome

    Body mass index and outcome in renal transplant recipients: a systematic review and meta-analysis

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    BACKGROUND: Whether overweight or obese end stage renal disease (ESRD) patients are suitable for renal transplantation (RT) is often debated. The objective of this review and meta-analysis was to systematically investigate the outcome of low versus high BMI recipients after RT. METHODS: Comprehensive searches were conducted in MEDLINE OvidSP, Web of Science, Google Scholar, Embase, and CENTRAL (the Cochrane Library 2014, issue 8). We reviewed four major guidelines that are available regarding (potential) RT recipients. The methodology was in accordance with the Cochrane Handbook for Systematic Reviews of Interventions and written based on the PRISMA statement. The quality assessment of studies was performed by using the GRADE tool. A meta-analysis was performed using Review Manager 5.3. Random-effects models were used. RESULTS: After identifying 5,526 studies addressing this topic, 56 studies were included. We extracted data for 37 outcome measures (including data of more than 209,000 RT recipients), of which 26 could be meta-analysed. The following outcome measures demonstrated significant differences in favour of low BMI (<30) recipients: mortality (RR = 1.52), delayed graft function (RR = 1.52), acute rejection (RR = 1.17), 1-, 2-, and 3-year graft survival (RR = 0.97, 0.95, and 0.97), 1-, 2-, and 3-year patient survival (RR = 0.99, 0.99, and 0.99), wound infection and dehiscence (RR = 3.13 and 4.85), NODAT (RR = 2.24), length of hospital stay (2.31 days), operation duration (0.77 hours), hypertension (RR = 1.35), and incisional hernia (RR = 2.72). However, patient survival expressed in hazard ratios was in significant favour of high BMI recipients. Differences in other outcome parameters were not significant. CONCLUSIONS: Several of the pooled outcome measurements show significant benefits for ‘low’ BMI (<30) recipients. Therefore, we postulate that ESRD patients with a BMI >30 preferably should lose weight prior to RT. If this cannot be achieved with common measures, in morbidly obese RT candidates, bariatric surgery could be considered. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12916-015-0340-5) contains supplementary material, which is available to authorized users

    Loss-of-function mutations in SLC30A8 protect against type 2 diabetes.

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    Neðst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinn View/OpenLoss-of-function mutations protective against human disease provide in vivo validation of therapeutic targets, but none have yet been described for type 2 diabetes (T2D). Through sequencing or genotyping of ~150,000 individuals across 5 ancestry groups, we identified 12 rare protein-truncating variants in SLC30A8, which encodes an islet zinc transporter (ZnT8) and harbors a common variant (p.Trp325Arg) associated with T2D risk and glucose and proinsulin levels. Collectively, carriers of protein-truncating variants had 65% reduced T2D risk (P = 1.7 × 10(-6)), and non-diabetic Icelandic carriers of a frameshift variant (p.Lys34Serfs*50) demonstrated reduced glucose levels (-0.17 s.d., P = 4.6 × 10(-4)). The two most common protein-truncating variants (p.Arg138* and p.Lys34Serfs*50) individually associate with T2D protection and encode unstable ZnT8 proteins. Previous functional study of SLC30A8 suggested that reduced zinc transport increases T2D risk, and phenotypic heterogeneity was observed in mouse Slc30a8 knockouts. In contrast, loss-of-function mutations in humans provide strong evidence that SLC30A8 haploinsufficiency protects against T2D, suggesting ZnT8 inhibition as a therapeutic strategy in T2D prevention.US National Institutes of Health (NIH) Training 5-T32-GM007748-33 Doris Duke Charitable Foundation 2006087 Fulbright Diabetes UK Fellowship BDA 11/0004348 Broad Institute from Pfizer, Inc. NIH U01 DK085501 U01 DK085524 U01 DK085545 U01 DK085584 Swedish Research Council Dnr 521-2010-3490 Dnr 349-2006-237 European Research Council (ERC) GENETARGET T2D GA269045 ENGAGE 2007-201413 CEED3 2008-223211 Sigrid Juselius Foundation Folkh lsan Research Foundation ERC AdG 293574 Research Council of Norway 197064/V50 KG Jebsen Foundation University of Bergen Western Norway Health Authority Lundbeck Foundation Novo Nordisk Foundation Wellcome Trust WT098017 WT064890 WT090532 WT090367 WT098381 Uppsala University Swedish Research Council and the Swedish Heart- Lung Foundation Academy of Finland 124243 102318 123885 139635 Finnish Heart Foundation Finnish Diabetes Foundation, Tekes 1510/31/06 Commission of the European Community HEALTH-F2-2007-201681 Ministry of Education and Culture of Finland European Commission Framework Programme 6 Integrated Project LSHM-CT-2004-005272 City of Kuopio and Social Insurance Institution of Finland Finnish Foundation for Cardiovascular Disease NIH/NIDDK U01-DK085545 National Heart, Lung, and Blood Institute (NHLBI) National Institute on Minority Health and Health Disparities N01 HC-95170 N01 HC-95171 N01 HC-95172 European Union Seventh Framework Programme, DIAPREPP Swedish Child Diabetes Foundation (Barndiabetesfonden) 5U01DK085526 DK088389 U54HG003067 R01DK072193 R01DK062370 Z01HG000024info:eu-repo/grantAgreement/EC/FP7/20201
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