247 research outputs found
Using chondroitin sulfate to improve the viability and biosynthesis of chondrocytes encapsulated in interpenetrating network (IPN) hydrogels of agarose and poly(ethylene glycol) diacrylate
We recently introduced agarose-poly(ethylene glycol) diacrylate (PEGDA) interpenetrating network (IPN) hydrogels to cartilage tissue engineering that were able to encapsulate viable cells and provide a significant improvement in mechanical performance relative to its two constituent hydrogels. The goal of the current study was to develop a novel synthesis protocol to incorporate methacrylated chondroitin sulfate (MCS) into the IPN design hypothesized to improve cell viability and biosynthesis. The IPN was formed by encapsulating porcine chondrocytes in agarose, soaking the construct in a solution of 1:10 MCS:PEGDA, which was then photopolymerized to form a copolymer network as the second network. The IPN with incorporated CS (CS-IPN) (~0.5 wt%) resulted in a 4- to 5-fold increase in the compressive elastic modulus relative to either the PEGDA or agarose gels. After 6 weeks of in vitro culture, more than 50% of the encapsulated chondrocytes remained viable within the CS-modified IPN, in contrast to 35% viability observed in the unmodified. At week 6, the CS-IPN had significantly higher normalized GAG contents (347 ± 34 µg/µg) than unmodified IPNs (158 ± 27 µg/µg, P < 0.05). Overall, the approach of incorporating biopolymers such as CS from native tissue may provide favorable micro-environment and beneficial signals to cells to enhance their overall performance in IPNs
Suicide in cancer patients in South East England from 1996 to 2005: a population-based study
BACKGROUND: Studies from around the world have shown that suicide risk is increased in cancer patients, but no previous detailed analysis has been carried out in England
Interaction of Copper-Amine With Southern Pine: Retention and Migration
The retention and leachability of copper in copper-amine (Cu-EA)-treated southern pine (SP) are influenced by the formulation and the composition of copper-amine treating solutions. The sources of copper used, Cu(OH)2, CuCO3, CuSO4, and Cu(NO3)2, in the copper-amine complex formulation affect the leachability of copper. Data show that copper-amine from CuSO4- and Cu(NO3)2-treated wood has less copper loss during laboratory water leaching than that from Cu(OH)2- and CuCO3-treated wood. Increasing the amine-to-copper molar ratio increases the copper retention by wood, but reduces the leach resistance of copper. The nature of amine ligands, such as monoethanolamine (primary amine), 2-methylamino-ethanol (secondary amine), and N, N-dimethyl-ethanolamine (tertiary amine), has some effect on copper retention and copper leaching. As the molecular weight of amine ligands increases, copper loss during leaching decreases
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Ethics, politics and embodied imagination in crafting scientific knowledge
This article explores ‘research-as-craft’ as a sensitizing concept for disclosing the presence of ethics and politics, as well as embodiment and imagination, in the doing and representation of scientific activity. Routinely unnoticed, marginalized or suppressed in methodology sections of articles and methodology textbooks, research-as-craft gestures towards messy, tacit, uncertain, yet rarely thematized, practices that are central to getting science done. To acknowledge and address the significance of research-as-craft in knowledge production, we show how it relates to three forms of reflexivity – constitutive, epistemic and disruptive. Through this we demonstrate the craftiness that is required when struggling with the indeterminacy that is endemic to the production and communication of scientific knowledge. By showing how empirical situations require imaginative interpretation by embodied researchers, we argue that our conception of research-as-craft facilitates appreciation of scientific inquiry as an indexical activity that involves the crafted object and the researcher in an ethico-political process of co-constituting knowledge
Plasma Proteomics of Renal Function: A Transethnic Meta-Analysis and Mendelian Randomization Study.
BACKGROUND: Studies on the relationship between renal function and the human plasma proteome have identified several potential biomarkers. However, investigations have been conducted largely in European populations, and causality of the associations between plasma proteins and kidney function has never been addressed. METHODS: A cross-sectional study of 993 plasma proteins among 2882 participants in four studies of European and admixed ancestries (KORA, INTERVAL, HUNT, QMDiab) identified transethnic associations between eGFR/CKD and proteomic biomarkers. For the replicated associations, two-sample bidirectional Mendelian randomization (MR) was used to investigate potential causal relationships. Publicly available datasets and transcriptomic data from independent studies were used to examine the association between gene expression in kidney tissue and eGFR. RESULTS: In total, 57 plasma proteins were associated with eGFR, including one novel protein. Of these, 23 were additionally associated with CKD. The strongest inferred causal effect was the positive effect of eGFR on testican-2, in line with the known biological role of this protein and the expression of its protein-coding gene (SPOCK2) in renal tissue. We also observed suggestive evidence of an effect of melanoma inhibitory activity (MIA), carbonic anhydrase III, and cystatin-M on eGFR. CONCLUSIONS: In a discovery-replication setting, we identified 57 proteins transethnically associated with eGFR. The revealed causal relationships are an important stepping stone in establishing testican-2 as a clinically relevant physiological marker of kidney disease progression, and point to additional proteins warranting further investigation.The KORA study was initiated and financed by the Helmholtz Zentrum München – German Research Center for Environmental Health, which is funded by the German Federal Ministry of Education and Research (BMBF) and by the State of Bavaria. This work was also supported by the Biomedical Research Program at Weill Cornell Medicine in Qatar, a program funded by the Qatar Foundation. K.S. is supported by Qatar National Research Fund (QNRF) grant no. NPRPC11-0115-180010. The Nord-Trøndelag Health Study (The HUNT Study) is a collaboration between HUNT Research Centre (Faculty of Medicine, Norwegian University of Science and Technology NTNU), Nord-Trøndelag County Council, Central Norway Health Authority, and the Norwegian Institute of Public Health. The HUNT part of the project re-used protein data that was originally analysed and paid for by Somalogic Inc, CO, USA. Somalogic had no role in the design and conduct of the study; collection of phenotypic data, statistical analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.
Professor John Danesh is funded by the National Institute for Health Research [Senior Investigator Award]. The views expressed are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care.
RNA-sequencing experiments and kidney gene expression studies were supported by British Heart Foundation project grants [PG/17/35/33001 and PG/19/16/34270] and Kidney Research UK grants [ RP_017_20180302 and RP_013_20190305] to M.T.
The German Diabetes Center is funded by the German Federal Ministry of Health (Berlin, Germany), the Ministry of Culture and Science of the state North Rhine-Westphalia (Düsseldorf, Germany), and grants from the German Federal Ministry of Education and Research (Berlin, Germany) to the German Center for Diabetes Research e.V. (DZD)
A randomised controlled trial of a patient based Diabetes recall and Management system: the DREAM trial: A study protocol [ISRCTN32042030]
BACKGROUND: Whilst there is broad agreement on what constitutes high quality health care for people with diabetes, there is little consensus on the most efficient way of delivering it. Structured recall systems can improve the quality of care but the systems evaluated to date have been of limited sophistication and the evaluations have been carried out in small numbers of relatively unrepresentative settings. Hartlepool, Easington and Stockton currently operate a computerised diabetes register which has to date produced improvements in the quality of care but performance has now plateaued leaving substantial scope for further improvement. This study will evaluate the effectiveness and efficiency of an area wide 'extended' system incorporating a full structured recall and management system, actively involving patients and including clinical management prompts to primary care clinicians based on locally-adapted evidence based guidelines. METHODS: The study design is a two-armed cluster randomised controlled trial of 61 practices incorporating evaluations of the effectiveness of the system, its economic impact and its impact on patient wellbeing and functioning
Expression variability of co-regulated genes differentiates Saccharomyces cerevisiae strains
Background: Saccharomyces cerevisiae (Baker’s yeast) is found in diverse ecological niches and is characterized by
high adaptive potential under challenging environments. In spite of recent advances on the study of yeast
genome diversity, little is known about the underlying gene expression plasticity. In order to shed new light onto
this biological question, we have compared transcriptome profiles of five environmental isolates, clinical and
laboratorial strains at different time points of fermentation in synthetic must medium, during exponential and
stationary growth phases.
Results: Our data unveiled diversity in both intensity and timing of gene expression. Genes involved in glucose
metabolism and in the stress response elicited during fermentation were among the most variable. This gene
expression diversity increased at the onset of stationary phase (diauxic shift). Environmental isolates showed lower
average transcript abundance of genes involved in the stress response, assimilation of nitrogen and vitamins, and
sulphur metabolism, than other strains. Nitrogen metabolism genes showed significant variation in expression
among the environmental isolates.
Conclusions: Wild type yeast strains respond differentially to the stress imposed by nutrient depletion, ethanol
accumulation and cell density increase, during fermentation of glucose in synthetic must medium. Our results
support previous data showing that gene expression variability is a source of phenotypic diversity among closely
related organisms.Fundação para a Ciência e TecnologiaThe authors wish to thank Adega Cooperativa da Bairrada, Cantanhede,
Portugal, for providing the commercial strains
“Se viveres como louco, sabes que hás de morrer sem juízo”: as orientações para o bem morrer na literatura cristã portuguesa do século XVIII
Resumo Orientar os fiéis para uma vida santificada e instruí-los para uma boa morte foram objetivos muito comuns na literatura religiosa portuguesa do período moderno, especialmente aquela divulgada no século XVIII e que se propunha a definir e propagar virtudes morais e comportamentos que garantissem o bem morrer. Nosso objetivo, neste artigo, é o de analisar as orientações que todo fiel católico deveria observar como preparação prévia para a morte nas obras Sermão da Missão da quarta tarde da quaresma (1734), Terceiro Instruído na Virtude (1742) e Mestre da Virtude(1745), produzidas pelo padre dominicano português João Franc
Prevalence of pfmdr1, pfcrt, pfdhfr and pfdhps mutations associated with drug resistance, in Luanda, Angola
<p>Abstract</p> <p>Background</p> <p>Malaria is the infectious disease causing the highest morbidity and mortality in Angola and due to widespread chloroquine (CQ) resistance, the country has recently changed its first-line treatment recommendations for uncomplicated malaria, from CQ to artemisinin combination therapies (ACT) in adults, and sulphadoxine/pyrimethamine (S/P) in pregnant women. Loss of SP sensitivity is, however, progressing rapidly in Africa and, in this study, were investigated a number of molecular markers associated to CQ and S/P.</p> <p>Methods</p> <p>Blood samples were collected from 245 children with uncomplicated malaria, admitted at the Pediatric Hospital Dr. David Bernardino (HPDB), Angola, and the occurrence of mutations in <it>Plasmodium falciparum </it>was investigated in the <it>pfmdr1 </it>(N86Y) and <it>pfcrt </it>(K76T) genes, associated with CQ resistance, as well as in <it>pfdhfr </it>(C59R) and <it>pfdhps </it>(K540E), conferring SP resistance.</p> <p>Results</p> <p>The frequencies of <it>pfmdr1 </it>mutations in codon 86 were 28.6% N, 61.3% Y and 10.1% mixed infections (NY). The frequency of <it>pfcrt </it>mutations in codon 76 were 93.9% K, 5.7% T and 0.4% mixed infections (KT). For <it>pfdhfr </it>the results were in codon 59, 60.6% C, 20.6% R and 18.8% mixed infections (CR). Concerning <it>pfdhps</it>, 6.3% of the isolates were bearers of the mutation 540E and 5.4% mixed infections (K540E).</p> <p>Conclusion</p> <p>The results of this epidemiologic study showed high presence of CQ resistance markers while for SP a much lower prevalence was detected for the markers under study.</p
Changes in muscle-tendon unit length-force characteristics following experimentally induced photothrombotic stroke cannot be explained by changes in muscle belly structure.
Purpose The aim of this study was to assess the effects of experimentally induced photothrombotic stroke on structural and mechanical properties of rat m. flexor carpi ulnaris. Methods Two groups of Young-adult male Sprague–Dawley rats were measured: stroke (n = 9) and control (n = 7). Photothrombotic stroke was induced in the forelimb region of the primary sensorimotor cortex. Four weeks later, muscle–tendon unit and muscle belly length–force characteristics of the m. flexor carpi ulnaris, mechanical interaction with the neighbouring m. palmaris longus, the number of sarcomeres in series within muscle fibres, and the physiological cross-sectional area were measured. Results Stroke resulted in higher force and stiffness of the m. flexor carpi ulnaris at optimum muscle–tendon unit length, but only for the passive conditions. Stroke did not alter the length–force characteristics of m. flexor carpi ulnaris muscle belly, morphological characteristics, and the extent of mechanical interaction with m. palmaris longus muscle. Conclusion The higher passive force and passive stiffness at the muscle–tendon unit level in the absence of changes in structural and mechanical characteristics of the muscle belly indicates that the experimentally induced stroke resulted in an increased stiffness of the tendon
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