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91.
Wei Luo Thin Nguyen Melanie Nichols Truyen Tran Santu Rana Sunil Gupta Dinh Phung Svetha Venkatesh Steve Allender 《PloS one》2015,10(5)
For years, we have relied on population surveys to keep track of regional public health statistics, including the prevalence of non-communicable diseases. Because of the cost and limitations of such surveys, we often do not have the up-to-date data on health outcomes of a region. In this paper, we examined the feasibility of inferring regional health outcomes from socio-demographic data that are widely available and timely updated through national censuses and community surveys. Using data for 50 American states (excluding Washington DC) from 2007 to 2012, we constructed a machine-learning model to predict the prevalence of six non-communicable disease (NCD) outcomes (four NCDs and two major clinical risk factors), based on population socio-demographic characteristics from the American Community Survey. We found that regional prevalence estimates for non-communicable diseases can be reasonably predicted. The predictions were highly correlated with the observed data, in both the states included in the derivation model (median correlation 0.88) and those excluded from the development for use as a completely separated validation sample (median correlation 0.85), demonstrating that the model had sufficient external validity to make good predictions, based on demographics alone, for areas not included in the model development. This highlights both the utility of this sophisticated approach to model development, and the vital importance of simple socio-demographic characteristics as both indicators and determinants of chronic disease. 相似文献
92.
Excess body mass index‐ and waist circumference‐years and incident cardiovascular disease: The CARDIA study
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93.
Fernanda Fortes de Araujo Rana Nagarkatti Charu Gupta Ana Paula Marino Alain Debrabant 《PLoS neglected tropical diseases》2015,9(1)
Drug discovery initiatives, aimed at Chagas treatment, have been hampered by the lack of standardized drug screening protocols and the absence of simple pre-clinical assays to evaluate treatment efficacy in animal models. In this study, we used a simple Enzyme Linked Aptamer (ELA) assay to detect T. cruzi biomarker in blood and validate murine drug discovery models of Chagas disease. In two mice models, Apt-29 ELA assay demonstrated that biomarker levels were significantly higher in the infected group compared to the control group, and upon Benznidazole treatment, their levels reduced. However, biomarker levels in the infected treated group did not reduce to those seen in the non-infected treated group, with 100% of the mice above the assay cutoff, suggesting that parasitemia was reduced but cure was not achieved. The ELA assay was capable of detecting circulating biomarkers in mice infected with various strains of T. cruzi parasites. Our results showed that the ELA assay could detect residual parasitemia in treated mice by providing an overall picture of the infection in the host. They suggest that the ELA assay can be used in drug discovery applications to assess treatment efficacy in-vivo. 相似文献
94.
C5a receptor (C5aR) is one of the major chemoattractant receptors of the druggable proteome that binds C5a, the proinflammatory polypeptide of complement cascade, triggering inflammation and SEPSIS. Here, we report the model structures of C5aR in both inactive and peptide agonist (YSFKPMPLaR; a=D-Ala) bound meta-active state. Assembled in CYANA and evolved over molecular dynamics (MD) in POPC bilayer, the inactive C5aR demonstrates a topologically unique compact heptahelical bundle topology harboring a β-hairpin in extracellular loop 2 (ECL2), derived from the atomistic folding simulations. The peptide agonist bound meta-active C5aR deciphers the “site2” at an atomistic resolution in the extracellular surface (ECS), in contrast to the previously hypothesized inter-helical crevice. With estimated Ki≈2.75 μM, the meta-active C5aR excellently rationalizes the IC50 (0.1–13 μM) and EC50 (0.01–6 μM) values, displayed by the peptide agonist in several signaling studies. Moreover, with Ki≈5.3×105 μM, the “site2” also illustrates selectivity, by discriminating the stereochemical mutant peptide (YSFkPMPLaR; k=D-Lys), known to be inert toward C5aR, up to 1 mM concentration. Topologically juxtaposed between the structures of rhodopsin and CXCR1, the C5aR models also display excellent structural correlations with the other G-protein coupled receptors (GPCRs). The models elaborated in the current study unravel many important structural insights previously not known for regulating the agonist binding and activation mechanism of C5aR. 相似文献
95.
David W. Pennington Kirana Chomkhamsri Rana Pant Marc-Andree Wolf Giovanni Bidoglio Klaus Kögler Pavel Misiga Michel Sponar Bettina Lorz Guido Sonnemann Paolo Masoni Hongtao Wang Lin Ling Carla Castanho Chen Sau Soon Maurizio Fieschi Assunta Filareto Michael Hauschild 《The International Journal of Life Cycle Assessment》2010,15(3):231-237
Introduction
The European Commission is supporting the development of the International Reference Life Cycle Data System (ILCD). This consists primarily of the ILCD Handbook and the ILCD Data Network. This paper gives an insight into the scientific positions of business, governments, consultants, academics, and others that were expressed at this public consultation workshop.Workshop focus
The workshop focused on four of the topics of the main guidance documents of the ILCD Handbook: (1) general guidance on life cycle assessment (LCA); (2) guidance for generic and average life cycle inventory (LCI) data sets; (3) requirements for environmental impact assessment methods, models and indicators for LCA; and (4) review schemes for LCA.Workshop participation
This consultation workshop was attended by more than 120 participants during the 4 days of the workshop. Representatives came from 23 countries, from both within and outside the European Union.Workshop structure
Approximately half of the participants were from business associations or individual companies. Another 20% were governmental representatives. Others came predominantly from consultancies and academia.Results
This public consultation workshop provided valuable inputs into the overall ILCD Handbook developments as well as for further development. This paper focuses on some of the main scientific issues that were raised. 相似文献96.
97.
McNeela EA Burke A Neill DR Baxter C Fernandes VE Ferreira D Smeaton S El-Rachkidy R McLoughlin RM Mori A Moran B Fitzgerald KA Tschopp J Pétrilli V Andrew PW Kadioglu A Lavelle EC 《PLoS pathogens》2010,6(11):e1001191
Pneumolysin (PLY) is a key Streptococcus pneumoniae virulence factor and potential candidate for inclusion in pneumococcal subunit vaccines. Dendritic cells (DC) play a key role in the initiation and instruction of adaptive immunity, but the effects of PLY on DC have not been widely investigated. Endotoxin-free PLY enhanced costimulatory molecule expression on DC but did not induce cytokine secretion. These effects have functional significance as adoptive transfer of DC exposed to PLY and antigen resulted in stronger antigen-specific T cell proliferation than transfer of DC exposed to antigen alone. PLY synergized with TLR agonists to enhance secretion of the proinflammatory cytokines IL-12, IL-23, IL-6, IL-1β, IL-1α and TNF-α by DC and enhanced cytokines including IL-17A and IFN-γ by splenocytes. PLY-induced DC maturation and cytokine secretion by DC and splenocytes was TLR4-independent. Both IL-17A and IFN-γ are required for protective immunity to pneumococcal infection and intranasal infection of mice with PLY-deficient pneumococci induced significantly less IFN-γ and IL-17A in the lungs compared to infection with wild-type bacteria. IL-1β plays a key role in promoting IL-17A and was previously shown to mediate protection against pneumococcal infection. The enhancement of IL-1β secretion by whole live S. pneumoniae and by PLY in DC required NLRP3, identifying PLY as a novel NLRP3 inflammasome activator. Furthermore, NLRP3 was required for protective immunity against respiratory infection with S. pneumoniae. These results add significantly to our understanding of the interactions between PLY and the immune system. 相似文献
98.
The present study was aimed at formulating tablets comprising of coating susceptible to microbial enzyme degradation for releasing budesonide in the colon. Tablets prepared by using Avicel® pH 102 as diluent and Eudragit® L100-55 as binder were coated to a weight gain of 10% w/w employing aqueous mixtures containing chitosan (CH) and chondroitin sulfate (CS). The interpolymer complex between CH and CS was characterized using Fourier transform infrared (FTIR) and differential scanning calorimetery (DSC) studies. The tablets were evaluated for release of budesonide through in vitro in vivo studies. Formation of bonds between –COO? and –OSO 3 ? groups of CS and –NH 3 + groups of CH was evident in the FTIR spectra of these interpolymer complexed (IPC) films. The DSC thermograms of these films revealed one endothermic transition between 190°C and 205°C, suggesting the formation of new bonds in the IPC. The pH sensitive swelling exhibited by these films was observed to be a function of CH concentration. Tablets coated with aqueous mixtures containing 40:60 or 50:50 ratio of CH/CS totally prevented the release of budesonide in pH 1.2 buffer. The peaks (FTIR) and endothermic transitions (DSC) characteristic of interpolymer complexation were observed to remain unaffected after sequential exposure of the films to pH 1.2 and pH 7.4 buffer IP. This proved the versatility of these IPC films for colon delivery. C max of 1,168.99 and 1,174.2 ng/mL, respectively, at 12 and 8 h post-oral dosing of tablets coated with 40:60 or 50:50 ratio of CH/CS was observed in rats. The aqueous CH/CS (40:60) coating could provide a facile method for delivering budesonide to the colon. 相似文献
99.
Chae PS Rasmussen SG Rana RR Gotfryd K Chandra R Goren MA Kruse AC Nurva S Loland CJ Pierre Y Drew D Popot JL Picot D Fox BG Guan L Gether U Byrne B Kobilka B Gellman SH 《Nature methods》2010,7(12):1003-1008
The understanding of integral membrane protein (IMP) structure and function is hampered by the difficulty of handling these proteins. Aqueous solubilization, necessary for many types of biophysical analysis, generally requires a detergent to shield the large lipophilic surfaces of native IMPs. Many proteins remain difficult to study owing to a lack of suitable detergents. We introduce a class of amphiphiles, each built around a central quaternary carbon atom derived from neopentyl glycol, with hydrophilic groups derived from maltose. Representatives of this maltose-neopentyl glycol (MNG) amphiphile family show favorable behavior relative to conventional detergents, as manifested in multiple membrane protein systems, leading to enhanced structural stability and successful crystallization. MNG amphiphiles are promising tools for membrane protein science because of the ease with which they may be prepared and the facility with which their structures may be varied. 相似文献
100.
Byrt CS Platten JD Spielmeyer W James RA Lagudah ES Dennis ES Tester M Munns R 《Plant physiology》2007,143(4):1918-1928
Bread wheat (Triticum aestivum) has a greater ability to exclude Na+ from its leaves and is more salt tolerant than durum wheat (Triticum turgidum L. subsp. durum [Desf.]). A novel durum wheat, Line 149, was found to contain a major gene for Na+ exclusion, Nax2, which removes Na+ from the xylem in the roots and leads to a high K+-to-Na+ ratio in the leaves. Nax2 was mapped to the distal region on chromosome 5AL based on linkage to microsatellite markers. The Nax2 locus on 5AL coincides with the locus for a putative Na+ transporter, HKT1;5 (HKT8). The Nax2 region on 5AL is homoeologous to the region on chromosome 4DL containing the major Na+ exclusion locus in bread wheat, Kna1. A gene member of the HKT1;5 family colocates to the deletion bin containing Kna1 on chromosome 4DL. This work provides evidence that Nax2 and Kna1 are strongly associated with HKT1;5 genes. 相似文献