673 research outputs found
Field induced magnetic transition and metastability in Co substituted
A detailed investigation of first order ferrimagnetic (FRI) to
antiferromagnetic (AFM) transition in Co (15%) doped is carried out.
These measurements demonstrate anomalous thermomagnetic irreversibility and
glass-like frozen FRI phase at low temperatures. The irreversibility arising
between the supercooling and superheating spinodals is distinguised in an
ingenious way from the irreversibility arising due to kinetic arrest. Field
annealing measurements shows reentrant FRI-AFM-FRI transition with increasing
temperature. These measurements also show that kinetic arrest band and
supercooling band are anitcorrelated i.e regions which are kinetically arrested
at higher temperature have lower supercooling temperature and vice versa.Comment: 10 pages, 8 figure
Upregulation of brain renin angiotensin system by 27-hydroxycholesterol in Alzheimer's disease
In spite of the fact that cholesterol does not pass the blood-brain barrier, hypercholesterolemia has been linked to increase Alzheimer's disease (AD) risk. Hypertension is another risk factor and angiotensin converting enzyme (ACE) activity is known to be increased in AD. Furthermore, a lower incidence of AD has been reported in patients taking anti-hypertensive drugs. Here we show that the levels of angiotensinogen (AGT) and ACE are increased in the cerebrospinal fluid (CSF) of patients with mild cognitive impairment and AD. Moreover, we show ACE activity in the CSF to be positively correlated with both plasma and CSF levels of 27-hydroxycholesterol (27-OH), an oxysterol known to pass through the BBB and taken up from the circulation by the brain. In addition, treatment of rat primary neurons, astrocytes, and human neuroblastoma cells with 27-OH resulted in increased production of AGT. Our results demonstrate that upregulation of renin-angiotensin system (RAS) in AD brains occurs not only at the enzymatic level (ACE) but also at the substrate level (AGT). The possibility that 27-OH is part of a mechanism linking hypercholesterolemia with increased brain RAS activity and increased AD risk is discussed
Characterization of endosperm proteins and bread-making quality in wheat breeding lines carrying resistance genes for Mayetiola destructor and/or Heterodera avenae.
The experimental material included thirteen bread wheat-breeding lines that carry genes for resistance to M. destruc¬tor and/or H. avenae. The sources of these resistances are the wild species Ae. triuncialis and Ae. ventricosa (lines TR and H-93, respectively) (Delibes et al. 1993, 1997; Romero et al. 1998). We have determined the composition in HMW-glutenin subunits (related with bread-making quality), puroindoline proteins (related with hardness of grain), and waxy proteins (related with starch viscosity). In addition to, of prolamins by electrophoresis SDS-PAGE indicated the homogeneity of the lines
Synthesis and in vivo evaluation of non-hepatotoxic acetaminophen analogs
A series of acetaminophen (APAP) analogs, 2-(1,1-dioxido-3-oxo-1,2-benzisothiazol-2(3H)-yl)-N-(4-hydroxyphenyl)alkanecarboxamides, bearing a heterocyclic moiety linked to the p-acylaminophenol fragment, were prepared in a general project to develop APAP analogs with modulated pharmacokinetic profiles. Unexpectedly, the products described maintained the in vivo analgesic profile, while the characteristic hepatotoxicity of APAP was consistently reduced. One of the products, 5a, was studied in vivo in comparison with APAP. Compound 5a displayed an analgesic efficacy comparable to that of APAP. A relatively high acute oral dose of 5a (6 mmol/kg) produced no measurable toxicity, whereas the equimolar dose of APAP increased transaminase activity, depleted hepatic and renal glutathione, and resulted in mortality. In human hepatocytes (HEPG-2) and in human primary cultures of normal liver cells, APAP, but not 5a, was associated with apoptotic cell death, Fas-ligand up-regulation, and CAR (constitutive androstane receptor) activation, contributing to a favorable safety profile of 5a as an orally delivered analgesic.MDA972-03-C-010 (Defense Advanced Research Programs Agency-DARPA)Neurobiotechnology Program of Louisian
An assigned responsibility system for robotic teleoperation control
This paper proposes an architecture that explores a gap in the spectrum of existing strategies for robot control mode switching in adjustable autonomy. In situations where the environment is reasonably known and/or predictable, pre-planning these control changes could relieve robot operators of the additional task of deciding when and how to switch. Such a strategy provides a clear division of labour between the automation and the human operator(s) before the job even begins, allowing for individual responsibilities to be known ahead of time, limiting confusion and allowing rest breaks to be planned. Assigned Responsibility is a new form of adjustable autonomy-based teleoperation that allows the selective inclusion of automated control elements at key stages of a robot operation plan’s execution. Progression through these stages is controlled by automatic goal accomplishment tracking. An implementation is evaluated through engineering tests and a usability study, demonstrating the viability of this approach and offering insight into its potential applications
Synaptic proteins predict cognitive decline in Alzheimer's disease and Lewy body dementia
Introduction:Our objective was to compare the levels of three synaptic proteins involved in different steps of the synaptic transmission: Rab3A, SNAP25, and neurogranin, in three common forms of dementia: Alzheimer's disease (AD), dementia with Lewy bodies (DLB), and Parkinson's disease dementia. Methods:A total of 129 postmortem human brain samples were analyzed in brain regional specific manner exploring their associations with morphologic changes and cognitive decline. Results:We have observed robust changes reflecting synaptic dysfunction in all studied dementia groups. There were significant associations between the rate of cognitive decline and decreased levels of Rab3 in DLB in the inferior parietal lobe and SNAP25 in AD in the prefrontal cortex. Of particular note, synaptic proteins significantly discriminated between dementia cases and controls with over 90% sensitivity and specificity. Discussion:Our findings suggest that the proposition that synaptic markers can predict cognitive decline in AD, should be extended to Lewy body diseases
wKinMut: An integrated tool for the analysis and interpretation of mutations in human protein kinases
BACKGROUND: Protein kinases are involved in relevant physiological functions and a broad number of mutations in this superfamily have been reported in the literature to affect protein function and stability. Unfortunately, the exploration of the consequences on the phenotypes of each individual mutation remains a considerable challenge. RESULTS: The wKinMut web-server offers direct prediction of the potential pathogenicity of the mutations from a number of methods, including our recently developed prediction method based on the combination of information from a range of diverse sources, including physicochemical properties and functional annotations from FireDB and Swissprot and kinase-specific characteristics such as the membership to specific kinase groups, the annotation with disease-associated GO terms or the occurrence of the mutation in PFAM domains, and the relevance of the residues in determining kinase subfamily specificity from S3Det. This predictor yields interesting results that compare favourably with other methods in the field when applied to protein kinases. Together with the predictions, wKinMut offers a number of integrated services for the analysis of mutations. These include: the classification of the kinase, information about associations of the kinase with other proteins extracted from iHop, the mapping of the mutations onto PDB structures, pathogenicity records from a number of databases and the classification of mutations in large-scale cancer studies. Importantly, wKinMut is connected with the SNP2L system that extracts mentions of mutations directly from the literature, and therefore increases the possibilities of finding interesting functional information associated to the studied mutations. CONCLUSIONS: wKinMut facilitates the exploration of the information available about individual mutations by integrating prediction approaches with the automatic extraction of information from the literature (text mining) and several state-of-the-art databases. wKinMut has been used during the last year for the analysis of the consequences of mutations in the context of a number of cancer genome projects, including the recent analysis of Chronic Lymphocytic Leukemia cases and is publicly available at http://wkinmut.bioinfo.cnio.es
Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study
Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world.
Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231.
Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001).
Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication
Neutron Capture Cross Sections of Zr and La: Probing Neutron Exposure and Neutron Flux in Red Giant Stars
Modifying effect of dual antiplatelet therapy on incidence of stent thrombosis according to implanted drug-eluting stent type
Aim To investigate the putative modifying effect of dual antiplatelet therapy (DAPT) use on the incidence of stent thrombosis at 3 years in patients randomized to Endeavor zotarolimus-eluting stent (E-ZES) or Cypher sirolimus-eluting stent (C-SES). Methods and results Of 8709 patients in PROTECT, 4357 were randomized to E-ZES and 4352 to C-SES. Aspirin was to be given indefinitely, and clopidogrel/ticlopidine for ≥3 months or up to 12 months after implantation. Main outcome measures were definite or probable stent thrombosis at 3 years. Multivariable Cox regression analysis was applied, with stent type, DAPT, and their interaction as the main outcome determinants. Dual antiplatelet therapy adherence remained the same in the E-ZES and C-SES groups (79.6% at 1 year, 32.8% at 2 years, and 21.6% at 3 years). We observed a statistically significant (P = 0.0052) heterogeneity in treatment effect of stent type in relation to DAPT. In the absence of DAPT, stent thrombosis was lower with E-ZES vs. C-SES (adjusted hazard ratio 0.38, 95% confidence interval 0.19, 0.75; P = 0.0056). In the presence of DAPT, no difference was found (1.18; 0.79, 1.77; P = 0.43). Conclusion A strong interaction was observed between drug-eluting stent type and DAPT use, most likely prompted by the vascular healing response induced by the implanted DES system. These results suggest that the incidence of stent thrombosis in DES trials should not be evaluated independently of DAPT use, and the optimal duration of DAPT will likely depend upon stent type (Clinicaltrials.gov number NCT00476957
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