3,441 research outputs found
Implementation of a comprehensive intervention for patients at high risk of cardiovascular disease in rural China: A pragmatic cluster randomized controlled trial
Objective: This study aims to assess whether a standard intervention package of cardiovascular disease (CVD) care was being delivered effectively, and if it was associated with improved lifestyle and biomedical indicators. Methods: In rural China, we implemented a pragmatic cluster randomized controlled trial for 12 months, randomized at the township hospital level, and compared with usual care. Intervention case management guideline, training and performance monitoring meeting and patient support activities were designed to fit within the job description of family doctors in the township hospitals and comprised: 1) prescription of a standardised package of medicines targeted at those with hypertension or diabetes; 2) advice about specific lifestyle interventions; and 3) advice about medication adherence. Participants were 50-74 years old, had hypertension and CVD risk scores >20% or diabetes, but were excluded if a history of severe CVD events. We also randomly selected 100 participants from six selected clusters per arm as a panel to collect intermediate biomedical indicators over time. Results: A total of 28,130 participants, in 33 intervention and 34 control township hospitals, were recruited. Compared with the control arm, participants in the intervention arm had substantially improved prescribing rates of anti-hypertensives, statins and aspirin (P0.05). Conclusion: Implementation of the package by family doctors was feasible and improved prescribing and some lifestyle changes. Additional measures such as reducing medication costs and patient education are required. Trial registration: Current Controlled Trials ISRCTN58988083
Electric Field Effects on Graphene Materials
Understanding the effect of electric fields on the physical and chemical
properties of two-dimensional (2D) nanostructures is instrumental in the design
of novel electronic and optoelectronic devices. Several of those properties are
characterized in terms of the dielectric constant which play an important role
on capacitance, conductivity, screening, dielectric losses and refractive
index. Here we review our recent theoretical studies using density functional
calculations including van der Waals interactions on two types of layered
materials of similar two-dimensional molecular geometry but remarkably
different electronic structures, that is, graphene and molybdenum disulphide
(MoS). We focus on such two-dimensional crystals because of they
complementary physical and chemical properties, and the appealing interest to
incorporate them in the next generation of electronic and optoelectronic
devices. We predict that the effective dielectric constant () of
few-layer graphene and MoS is tunable by external electric fields (). We show that at low fields ( V/\AA)
assumes a nearly constant value 4 for both materials, but increases at
higher fields to values that depend on the layer thickness. The thicker the
structure the stronger is the modulation of with the electric
field. Increasing of the external field perpendicular to the layer surface
above a critical value can drive the systems to an unstable state where the
layers are weakly coupled and can be easily separated. The observed dependence
of on the external field is due to charge polarization driven by
the bias, which show several similar characteristics despite of the layer
considered.Comment: Invited book chapter on Exotic Properties of Carbon Nanomatter:
Advances in Physics and Chemistry, Springer Series on Carbon Materials.
Editors: Mihai V. Putz and Ottorino Ori (11 pages, 4 figures, 30 references
Mechanisms and Impacts of Earth System Tipping Elements
Tipping elements are components of the Earth system which may respond nonlinearly to anthropogenic climate change by transitioning toward substantially different long-term states upon passing key thresholds or âtipping points.â In some cases, such changes could produce additional greenhouse gas emissions or radiative forcing that could compound global warming. Improved understanding of tipping elements is important for predicting future climate risks and their impacts. Here we review mechanisms, predictions, impacts, and knowledge gaps associated with 10 notable Earth system components proposed to be tipping elements. We evaluate which tipping elements are approaching critical thresholds and whether shifts may manifest rapidly or over longer timescales. Some tipping elements have a higher risk of crossing tipping points under middle-of-the-road emissions pathways and will possibly affect major ecosystems, climate patterns, and/or carbon cycling within the 21st century. However, literature assessing different emissions scenarios indicates a strong potential to reduce impacts associated with many tipping elements through climate change mitigation. The studies synthesized in our review suggest most tipping elements do not possess the potential for abrupt future change within years, and some proposed tipping elements may not exhibit tipping behavior, rather responding more predictably and directly to the magnitude of forcing. Nevertheless, uncertainties remain associated with many tipping elements, highlighting an acute need for further research and modeling to better constrain risks
Promoter hypermethylation and histone hypoacetylation contribute to pancreatic-duodenal homeobox 1 silencing in gastric cancer
Background and Aims: The expression of pancreatic-duodenal homeobox 1 (PDX1) in gastric cancer is aberrantly reduced. The aim of this study was to elucidate the regulation of DNA methylation and histone acetylation at the promoter for PDX1 silencing in gastric cancer. Methods: PDX1 expression in response to demethylation and acetylation was detected in human gastric cancer cell lines by reverse transcription-polymerase chain reaction (PCR) and western blot. Four CpG islands within the 5#-flanking region of PDX1 gene were analyzed with their transcription activities being detected by dual luciferase assay. Promoter hypermethylation was identified in gastric cancer cell lines and cancer tissues by methylation-specific PCR or bisulfite DNA sequencing PCR analysis. Histone acetylation was determined by chromatin immunoprecipitation (ChIP) assay. Results: Demethylation by 5â˛-aza-2â˛-deoxycytidine (5â˛-aza-dC) and/or acetylation by trichostatin A (TSA) restored PDX1 expression in gastric cancer cells. Hypermethylation was found in four CpG islands in six of seven cancer cell lines. However, only the distal CpG island located in the promoter fragment of PDX1, F383 (c.22063 to 21681 nt upstream of the ATG start codon) displayed significant transcriptional activity that could be suppressed by SssI methylase and increased by 5â˛-aza-dC and TSA. More than 70% of the single CpG sites in F383 were methylated with hypermethylation of F383 fragment more common in gastric cancerous tissues compared with the paired normal tissues (P < 0.05). ChIP assay showed F383 was also associated with low hypoacetylation level of the histones. Conclusion: Promoter hypermethylation and histone hypoacetylation contribute to PDX1 silencing in gastric cancer. Š The Author 2010. Published by Oxford University Press. All rights reserved.postprin
Effect of a training and educational intervention for physicians and caregivers on antibiotic prescribing for upper respiratory tract infections in children at primary care facilities in rural China: a cluster-randomised controlled trial
Background: Inappropriate antibiotic prescribing contributes to the generation of drug resistance worldwide, and is particularly common in China. We assessed the effectiveness of an antimicrobial stewardship programme aiming to reduce inappropriate antibiotic prescribing in paediatric outpatients by targeting providers and caregivers in primary care hospitals in rural China. Methods: We did a pragmatic, cluster-randomised controlled trial with a 6-month intervention period. Clusters were primary care township hospitals in two counties of Guangxi province in China, which were randomly allocated to the intervention group or the control group (in a 1:1 ratio in Rong county and in a 5:6 ratio in Liujiang county). Randomisation was stratified by county. Eligible participants were children aged 2â14 years who attended a township hospital as an outpatient and were given a prescription following a primary diagnosis of an upper respiratory tract infection. The intervention included clinician guidelines and training on appropriate prescribing, monthly prescribing peer-review meetings, and brief caregiver education. In hospitals allocated to the control group, usual care was provided, with antibiotics prescribed at the individual clinician's discretion. Patients were masked to their allocated treatment group but doctors were not. The primary outcome was the antibiotic prescription rate in children attending the hospitals, defined as the cluster-level proportion of prescriptions for upper respiratory tract infections in 2â14-year-old outpatients, issued during the final 3 months of the 6-month intervention period (endline), that included one or more antibiotics. The outcome was based on prescription records and analysed by modified intention-to-treat. This study is registered with the ISRCTN registry, number ISRCTN14340536.
Findings: We recruited all 25 eligible township hospitals in the two counties (14 hospitals in Rong county and 11 in Liujiang county), and randomly allocated 12 to the intervention group and 13 to the control group. We implemented the intervention in three internal pilot clusters between July 1, 2015, and Dec 31, 2015, and in the remaining nine intervention clusters between Oct 1, 2015 and March 31, 2016. Between baseline (the 3 months before implementation of the intervention) and endline (the final 3 months of the 6-month intervention period) the antibiotic prescription rate at the individual level decreased from 82% (1936/2349) to 40% (943/2351) in the intervention group, and from 75% (1922/2548) to 70% (1782/2552) in the control group. After adjusting for the baseline antibiotic prescription rate, stratum (county), and potentially confounding patient and prescribing doctor covariates, this endline difference between the groups represented an intervention effect (absolute risk reduction in antibiotic prescribing) of â29% (95% CI â42 to â16; p=0¡0002). Interpretation: In China's primary care setting, pragmatic interventions on antimicrobial stewardship targeting providers and caregivers substantially reduced prescribing of antibiotics for childhood upper respiratory tract infections. Funding: Department of International Development (UKAID) through Communicable Diseases Health Service Delivery
Using machine learning to enhance prediction of atrial fibrillation recurrence after catheter ablation
PPCAS: Implementation of a Probabilistic Pairwise Model for Consistency-Based Multiple Alignment in Apache Spark
Large-scale data processing techniques, currently known as Big-Data, are used to manage the huge amount of data that are generated by sequencers. Although these techniques have significant advantages, few biological applications have adopted them. In the Bioinformatic scientific area, Multiple Sequence Alignment (MSA) tools are widely applied for evolution and phylogenetic analysis, homology and domain structure prediction. Highly-rated MSA tools, such as MAFFT, ProbCons and T-Coffee (TC), use the probabilistic consistency as a prior step to the progressive alignment stage in order to improve the final accuracy. In this paper, a novel approach named PPCAS (Probabilistic Pairwise model for Consistency-based multiple alignment in Apache Spark) is presented. PPCAS is based on the MapReduce processing paradigm in order to enable large datasets to be processed with the aim of improving the performance and scalability of the original algorithm.This work was supported by the MEyC-Spain [contract TIN2014-53234-C2-2-R]
Cerebral involvement in a patient with Goodpasture's disease due to shortened induction therapy: a case report
<p>Abstract</p> <p>Introduction</p> <p>Goodpasture's disease is a rare immunological disease with formation of pathognomonic antibodies against renal and pulmonary basement membranes. Cerebral involvement has been reported in several cases in the literature, yet the pathogenetic mechanism is not entirely clear.</p> <p>Case presentation</p> <p>A 21-year-old Caucasian man with Goodpasture's disease and end-stage renal disease presented with two generalized seizures after a period of mild cognitive disturbance. Blood pressure and routine laboratory tests did not exceed the patient's usual values, and examination of cerebrospinal fluid was unremarkable. Cerebral magnetic resonance imaging (MRI) revealed multiple cortical and subcortical lesions on fluid-attenuated inversion recovery sequences. Since antiglomerular basement membrane antibodies were found to be positive with high titers, plasmapheresis was started. In addition, cyclophosphamide pulse therapy was given on day 13. Encephalopathy and MRI lesions disappeared during this therapy, and antiglomerular basement membrane antibodies were significantly reduced. Previous immunosuppressive therapy was performed without corticosteroids and terminated early after 3 months.</p> <p>The differential diagnostic considerations were cerebral vasculitis and posterior reversible encephalopathy syndrome. Vasculitis could be seen as an extrarenal manifestation of the underlying disease. Posterior reversible encephalopathy syndrome, on the other hand, can be triggered by immunosuppressive therapy and may appear without a hypertensive crisis.</p> <p>Conclusion</p> <p>A combination of central nervous system symptoms with a positive antiglomerular basement membrane test in a patient with Goodpasture's disease should immediately be treated as an acute exacerbation of the disease with likely cross-reactivity of antibodies with the choroid plexus. In our patient, a discontinuous strategy of immunosuppressive therapy may have favored recurrence of Goodpasture's disease.</p
The RN/CFT Correspondence Revisited
We reconsidered the quantum gravity description of the near horizon extremal
Reissner-Nordstr{\o}m black hole in the viewpoint of the AdS/CFT
correspondence. We found that, for pure electric case, the right moving central
charge of dual 1D CFT is which is different from the previous result of left moving sector obtained by warped AdS/CFT description. We
discussed the discrepancy in these two approaches and examined novel properties
of our result.Comment: revtex4, 16 pages, sign mistakes corrected, references include
Expression of Foxp3 in colorectal cancer but not in Treg cells correlates with disease progression in patients with colorectal cancer
Background: Regulatory T cells (Treg) expressing the transcription factor forkhead-box protein P3 (Foxp3) have been identified to counteract anti-tumor immune responses during tumor progression. Besides, Foxp3 presentation by cancer cells itself may also allow them to evade from effector T-cell responses, resulting in a survival benefit of the tumor. For colorectal cancer (CRC) the clinical relevance of Foxp3 has not been evaluated in detail. Therefore the aim of this study was to study its impact in colorectal cancer (CRC).
Methods and Findings: Gene and protein analysis of tumor tissues from patients with CRC was performed to quantify the expression of Foxp3 in tumor infiltrating Treg and colon cancer cells. The results were correlated with clinicopathological parameters and patients overall survival. Serial morphological analysis demonstrated Foxp3 to be expressed in cancer cells. High Foxp3 expression of the cancer cells was associated with poor prognosis compared to patients with low Foxp3 expression. In contrast, low and high Foxp3 level in tumor infiltrating Treg cells demonstrated no significant differences in overall patient survival.
Conclusions: Our findings strongly suggest that Foxp3 expression mediated by cancer cells rather than by Treg cells contribute to disease progression
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