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1.
HGG Adv ; 4(3): 100204, 2023 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-37250494

RESUMO

Identifying population-specific genetic variants associated with disease and disease-predisposing traits is important to provide insights into the genetic determinants of health and disease between populations, as well as furthering genomic justice. Various common pan-population polymorphisms at CETP associate with serum lipid profiles and cardiovascular disease. Here, sequencing of CETP identified a missense variant rs1597000001 (p.Pro177Leu) specific to Maori and Pacific people that associates with higher HDL-C and lower LDL-C levels. Each copy of the minor allele associated with higher HDL-C by 0.236 mmol/L and lower LDL-C by 0.133 mmol/L. The rs1597000001 effect on HDL-C is comparable with CETP Mendelian loss-of-function mutations that result in CETP deficiency, consistent with our data, which shows that rs1597000001 lowers CETP activity by 27.9%. This study highlights the potential of population-specific genetic analyses for improving equity in genomics and health outcomes for population groups underrepresented in genomic studies.


Assuntos
Povo Maori , População das Ilhas do Pacífico , Humanos , LDL-Colesterol , HDL-Colesterol/genética , Polimorfismo Genético , Proteínas de Transferência de Ésteres de Colesterol/genética
2.
Trials ; 23(1): 931, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36348460

RESUMO

BACKGROUND: External randomised pilot trials aim to assess whether a future definitive randomised controlled trial (RCT) is feasible. Pre-specified progression criteria help guide the interpretation of pilot trial findings to decide whether, and how, a definitive trial should be conducted. We aimed to examine how researchers report and plan to assess progression criteria in external pilot trial funding applications submitted to the NIHR Research for Patient Benefit Programme. METHODS: We conducted a cross-sectional study of progression criteria inclusion in Stage 1 (outline) and corresponding Stage 2 (full) funding applications for external randomised external pilot trials submitted to NIHR RfPB between July 2017 and July 2019. RESULTS: Of the 100 Stage 1 outline applications assessed, 95 were eligible for inclusion (of these, 52 were invited to Stage 2 full application; 43 were rejected) and 49/52 were eligible for inclusion at Stage 2 full application (of these, 35 were awarded funding; 14 were rejected). Over half of applications assessed at Stage 1 (48/95, 51%), and 73% of those assessed at Stage 2 (36/49) included progression criteria in their research plans. Progression criteria were most often reported in a stop-go format, often with additional specified factors that should be considered when determining feasibility (Stage 1 33/48, 69%; Stage 2 21/36, 58%). Recruitment and retention were the most frequent indicators of feasibility to inform progression criteria. One-third of applications provided some justification or rationale for their targets (Stage 1 16/48, 33%; Stage 2 12/36, 33%). Funding committee feedback mentioned progression criteria in over 20% of applications (Stage 1 22/95, 23%; Stage 2 11/49, 22%) to either request the addition of progression criteria or provide justification for the criteria stipulated. CONCLUSIONS: Our findings indicate that researchers do not always include progression criteria in external randomised pilot trial applications submitted to research funders. This can result in a lack of transparency in the assessment of randomised pilot trial feasibility. TRIAL REGISTRATION: Open Science Framework osf.io/89ap7, registered 29th June 2021.


Assuntos
Projetos de Pesquisa , Humanos , Projetos Piloto , Estudos Transversais , Estudos de Viabilidade , Análise Custo-Benefício
3.
Pilot Feasibility Stud ; 7(1): 195, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34749831

RESUMO

BACKGROUND: Feasibility studies are often conducted before committing to a randomised controlled trial (RCT), yet there is little published evidence to inform how useful feasibility studies are, especially in terms of adding or reducing waste in research. This study attempted to examine how many feasibility studies demonstrated that the full trial was feasible and whether some feasibility studies were inherently likely to be feasible or not feasible, based on the topic area and/or research setting. METHODS: Keyword searches were conducted on the International Standard Randomised Controlled Trials Number (ISRCTN) registry to identify all completed feasibility studies which had been conducted in the UK. RESULTS: A total of 625 records from the 1933 identified were reviewed before it became evident that it would be futile to continue. Of 329 feasibility studies identified, 160 had a known outcome (49%), 133 (83%) trials were deemed to be feasible and only 27 (17%) were reported to be non-feasible. There were therefore too few studies to allow the intended comparison of differences in non-feasible studies by topic and/or setting. CONCLUSIONS: There were too few studies reported as non-feasible to draw any useful conclusions on whether topic and/or setting had an effect. However, the high feasibility rate (83%) may suggest that non-feasible studies are subject to publication bias or that many feasible studies are redundant and may be adding waste to the research pathway.

4.
Stem Cells Dev ; 29(14): 882-894, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32364057

RESUMO

Articular cartilage contains a subpopulation of tissue-specific progenitors that are an ideal cell type for cell therapies and generating neocartilage for tissue engineering applications. However, it is unclear whether the standard chondrogenic medium using transforming growth factor beta (TGFß) isoforms is optimal to differentiate these cells. We therefore used pellet culture to screen progenitors from immature bovine articular cartilage with a number of chondrogenic factors and discovered that bone morphogenetic protein-9 (BMP9) precociously induces their differentiation. This difference was apparent with toluidine blue staining and confirmed by biochemical and transcriptional analyses with BMP9-treated progenitors exhibiting 11-fold and 5-fold greater aggrecan and collagen type II (COL2A1) gene expression than TGFß1-treated progenitors. Quantitative gene expression analysis over 14 days highlighted the rapid and phased nature of BMP9-induced chondrogenesis with sequential activation of aggrecan then collagen type II, and negligible collagen type X gene expression. The extracellular matrix of TGFß1-treated progenitors analyzed using atomic force microscopy was fibrillar and stiff whist BMP9-induced matrix of cells more compliant and correspondingly less fibrillar. Polarized light microscopy revealed an annular pattern of collagen fibril deposition typified by TGFß1-treated pellets, whereas BMP9-treated pellets displayed a birefringence pattern that was more anisotropic. Remarkably, differentiated immature chondrocytes incubated as high-density cultures in vitro with BMP9 generated a pronounced anisotropic organization of collagen fibrils indistinguishable from mature adult articular cartilage, with cells in deeper zones arranged in columnar manner. This contrasted with cells grown with TGFß1, where a concentric pattern of collagen fibrils was visualized within tissue pellets. In summary, BMP9 is a potent chondrogenic factor for articular cartilage progenitors and is also capable of inducing morphogenesis of adult-like cartilage, a highly desirable attribute for in vitro tissue-engineered cartilage.


Assuntos
Cartilagem Articular/citologia , Condrogênese , Fator 2 de Diferenciação de Crescimento/metabolismo , Células-Tronco/citologia , Animais , Bovinos , Células Cultivadas , Colágeno/metabolismo , Regulação da Expressão Gênica , Fator 2 de Diferenciação de Crescimento/genética , Hidroxiprolina/metabolismo
5.
PLoS One ; 15(3): e0230118, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32163468

RESUMO

BACKGROUND: Research funders use a wide variety of application assessment processes yet there is little evidence on their relative advantages and disadvantages. A broad distinction can be made between processes with a single stage assessment of full proposals and those that first invite an outline, with full proposals invited at a second stage only for those which are shortlisted. This paper examines the effects of changing from a one-stage to a two-stage process within the UK's National Institute for Health Research's (NIHR) Research for Patient Benefit (RfPB) Programme which made this change in 2015. METHODS: A retrospective comparative design was used to compare eight one-stage funding competitions (912 applications) with eight two-stage funding competitions (1090 applications). Comparisons were made between the number of applications submitted, number of peer and lay reviews required, the duration of the funding round, average external peer review scores, and the total costs involved. RESULTS: There was a mean number of 114 applications per funding round for the one-stage process and 136 for the two-stage process. The one-stage process took a mean of 274 days and the two-stage process 348 days to complete, although those who were not funded (i.e. the majority) were informed at a mean of 195 days (mean 79 days earlier) under the two-stage process. The mean peer review score for full applications using the one-stage process was 6.46 and for the two-stage process 6.82 (5.6% difference using a 1-10 scale (with 10 being the highest), but there was no significant difference between the lay reviewer scores. The one-stage process required a mean of 423 peer reviews and 102 lay reviewers and the two-stage process required a mean of 208 peer reviews and 50 lay reviews (mean difference of 215 peer reviews and 52 lay reviews) per funding round. Overall cost per funding round changed from £148,908 for the one-stage process to £105,342 for the two-stage process saving approximately £43,566 per round. CONCLUSION: We conclude that a two-stage application process increases the number of applications submitted to a funding round, is less burdensome and more efficient for all those involved with the process, is cost effective and has a small increase in peer reviewer scores. For the addition of fewer than 11 weeks to the process substantial efficiencies are gained which benefit funders, applicants and science. Funding agencies should consider adopting a two-stage application assessment process.


Assuntos
Organização do Financiamento/métodos , Revisão da Pesquisa por Pares , Análise Custo-Benefício , Bases de Dados Factuais , Organização do Financiamento/normas , Humanos , National Institutes of Health (U.S.) , Estudos Retrospectivos , Estados Unidos
6.
PLoS One ; 13(4): e0195951, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29684043

RESUMO

In the context of avoiding research waste, the conduct of a feasibility study before a clinical trial should reduce the risk that further resources will be committed to a trial that is likely to 'fail'. However, there is little evidence indicating whether feasibility studies add to or reduce waste in research. Feasibility studies funded by the National Institute for Health Research's (NIHR) Research for Patient Benefit (RfPB) programme were examined to determine how many had published their findings, how many had applied for further funding for a full trial and the timeframe in which both of these occurred. A total of 120 feasibility studies which had closed by May 2016 were identified and each Principal Investigator (PI) was sent a questionnaire of which 89 responses were received and deemed suitable for analysis. Based on self reported answers from the PIs a total of 57 feasibility studies were judged as feasible, 20 were judged not feasible and for 12 it was judged as uncertain whether a full trial was feasible. The RfPB programme had spent approximately £19.5m on the 89 feasibility studies of which 16 further studies had been subsequently funded to a total of £16.8m. The 20 feasibility studies which were judged as not feasible potentially saved up to approximately £20m of further research funding which would likely to have not completed successfully. The average RfPB feasibility study took 31 months (range 18 to 48) to complete and cost £219,048 (range £72,031 to £326,830) and the average full trial funded from an RfPB feasibility study took 42 months (range 26 to 55) to complete and cost £1,163,996 (range £321,403 to £2,099,813). The average timeframe of feasibility study and full trial was 72 months (range 56 to 91), however in addition to this time an average of 10 months (range -7 to 29) was taken between the end of the feasibility study and the application for the full trial, and a further average of 18 months (range 13 to 28) between the application for the full trial and the start of the full trial. Approximately 58% of the 89 feasibility studies had published their findings with the majority of the remaining studies still planning to publish. Due to the long time frames involved a number of studies were still in the process of publishing the feasibility findings and/or applying for a full trial. Feasibility studies are potentially useful at avoiding waste and de-risking funding investments of more expensive full trials, however there is a clear time delay and therefore some potential waste in the existing research pathway.


Assuntos
Análise Custo-Benefício/métodos , Estudos de Viabilidade , Ensaios Clínicos como Assunto/economia , Humanos , Projetos de Pesquisa , Fatores de Tempo
7.
Sci Rep ; 7(1): 3699, 2017 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-28623328

RESUMO

Platelet-rich plasma (PRP) is used to stimulate the repair of acute and chronic cartilage damage even though there is no definitive evidence of how this is achieved. Chondrocytes in injured and diseased situations frequently re-express phenotypic biomarkers of immature cartilage so tissue maturation is a potential pathway for restoration of normal structure and function. We used an in vitro model of growth factor-induced maturation to perform a comparative study in order to determine whether PRP can also induce this specific form of remodeling that is characterised by increased cellular proliferation and tissue stiffness. Gene expression patterns specific for maturation were mimicked in PRP treated cartilage, with chondromodulin, collagen types II/X downregulated, deiodinase II and netrin-1 upregulated. PRP increased cartilage surface cell density 1.5-fold (P < 0.05), confirmed by bromodeoxyuridine incorporation and proportionate increases in proliferating cell nuclear antigen gene expression. Atomic force microscopy analysis of PRP and growth factor treated cartilage gave a 5-fold increase in stiffness correlating with a 10-fold upregulation of lysyl oxidase like-1 gene expression (P < 0.001). These data show PRP induces key aspects of post-natal maturation in immature cartilage and provides the basis to evaluate a new biological rationale for its activity when used clinically to initiate joint repair.


Assuntos
Aminoácido Oxirredutases/genética , Cartilagem Articular/citologia , Cartilagem Articular/metabolismo , Condrogênese/genética , Plasma Rico em Plaquetas , Ativação Transcricional , Aminoácido Oxirredutases/metabolismo , Animais , Biomarcadores , Bovinos , Diferenciação Celular/genética , Proliferação de Células , Imunofluorescência , Regulação da Expressão Gênica , Masculino
8.
Cochrane Database Syst Rev ; (7): CD009445, 2013 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-23832767

RESUMO

BACKGROUND: Achieving informed consent is a core clinical procedure and is required before any surgical or invasive procedure is undertaken.  However, it is a complex process which requires patients be provided with information which they can understand and retain, opportunity to consider their options, and to be able to express their opinions and ask questions.  There is evidence that at present some patients undergo procedures without informed consent being achieved. OBJECTIVES: To assess the effects on patients, clinicians and the healthcare system of interventions to promote informed consent for patients undergoing surgical and other invasive healthcare treatments and procedures. SEARCH METHODS: We searched the following databases using keywords and medical subject headings: Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 5, 2012), MEDLINE (OvidSP) (1950 to July 2011), EMBASE (OvidSP) (1980 to July 2011) and PsycINFO (OvidSP) (1806 to July 2011). We applied no language or date restrictions within the search. We also searched reference lists of included studies. SELECTION CRITERIA: Randomised controlled trials and cluster randomised trials of interventions to promote informed consent for patients undergoing surgical and other invasive healthcare procedures. We considered an intervention to be intended to promote informed consent when information delivery about the procedure was enhanced (either by providing more information or through, for example, using new written materials), or if more opportunity to consider or deliberate on the information was provided. DATA COLLECTION AND ANALYSIS: Two authors assessed the search output independently to identify potentially-relevant studies, selected studies for inclusion, and extracted data. We conducted a narrative synthesis of the included trials, and meta-analyses of outcomes where there were sufficient data. MAIN RESULTS: We included 65 randomised controlled trials from 12 countries involving patients undergoing a variety of procedures in hospitals. Nine thousand and twenty one patients were randomised and entered into these studies. Interventions used various designs and formats but the main data for results were from studies using written materials, audio-visual materials and decision aids. Some interventions were delivered before admission to hospital for the procedure while others were delivered on admission.Only one study attempted to measure the primary outcome, which was informed consent as a unified concept, but this study was at high risk of bias.  More commonly, studies measured secondary outcomes which were individual components of informed consent such as knowledge, anxiety, and satisfaction with the consent process.  Important but less commonly-measured outcomes were deliberation, decisional conflict, uptake of procedures and length of consultation.Meta-analyses showed statistically-significant improvements in knowledge when measured immediately after interventions (SMD 0.53 (95% CI 0.37 to 0.69) I(2) 73%), shortly afterwards (between 24 hours and 14 days) (SMD 0.68 (95% CI 0.42 to 0.93) I(2) 85%) and at a later date (15 days or more) (SMD 0.78 (95% CI 0.50 to 1.06) I(2) 82%). Satisfaction with decision making was also increased (SMD 2.25 (95% CI 1.36 to 3.15) I(2) 99%) and decisional conflict was reduced (SMD -1.80 (95% CI -3.46 to -0.14) I(2) 99%). No statistically-significant differences were found for generalised anxiety (SMD -0.11 (95% CI -0.35 to 0.13) I(2) 82%), anxiety with the consent process (SMD 0.01 (95% CI -0.21 to 0.23) I(2) 70%) and satisfaction with the consent process (SMD 0.12 (95% CI -0.09 to 0.32) I(2) 76%). Consultation length was increased in those studies with continuous data (mean increase 1.66 minutes (95% CI 0.82 to 2.50) I(2) 0%) and in the one study with non-parametric data (control 8.0 minutes versus intervention 11.9 minutes, interquartile range (IQR) of 4 to 11.9 and 7.2 to 15.0 respectively). There were limited data for other outcomes.In general, sensitivity analyses removing studies at high risk of bias made little difference to the overall results.  AUTHORS' CONCLUSIONS: Informed consent is an important ethical and practical part of patient care.  We have identified efforts by researchers to investigate interventions which seek to improve information delivery and consideration of information to enhance informed consent.  The interventions used consistently improve patient knowledge, an important prerequisite for informed consent.  This is encouraging and these measures could be widely employed although we are not able to say with confidence which types of interventions are preferable. Our results should be interpreted with caution due to the high levels of heterogeneity associated with many of the main analyses although we believe there is broad evidence of beneficial outcomes for patients with the pragmatic application of interventions. Only one study attempted to measure informed consent as a unified concept.


Assuntos
Consentimento Livre e Esclarecido/estatística & dados numéricos , Procedimentos Cirúrgicos Operatórios , Técnicas de Apoio para a Decisão , Endoscopia , Humanos , Folhetos , Educação de Pacientes como Assunto/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Materiais de Ensino
9.
Org Biomol Chem ; 8(3): 539-45, 2010 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-20090969

RESUMO

The addition of 3,4-dimethoxybenzyl thiol 8, as a benzyl thiol surrogate, to racemic 4-hydroxycyclopent-2-enone 2 and 4-hydroxycyclohex-2-enone 15 gave the corresponding cis-adducts (+/-)-3-(3,4-dimethoxybenzylthio)-4-hydroxycyclopentanone 4b and (+/-)-3-(3,4-dimethoxybenzylthio)-4-hydroxycyclohexanone 16 with good diastereocontrol. In both cases, subsequent treatment with vinyl acetate, in the presence of a lipase enabled enantiomer resolution. Thus, (+)-16 and the acetate of its enantiomer, (-)-(1R,2S)-2-(3,4-dimethoxybenzylthio)-4-oxocyclohexyl acetate, (-)-17 were isolated in 98% enantiomeric excess. Based on the 1,4-dioxygenation pattern, (-)-17 can be used to prepare both enantiomers of 4-(tert-butyldimethylsilyloxy)cyclohex-2-enone 19. Firstly, saponification, with a sub-stoichiometric amount of NaOMe, followed by a one-pot silyl ether formation-sulfide elimination sequence gave (+)-19. Then using the same starting material a 6-step sequence, featuring a diastereoselective NaBH4 reduction and a Cope-type sulfoxide elimination, gave (-)-19.


Assuntos
Cicloexanonas/química , Cicloexanonas/metabolismo , Ciclopentanos/química , Ciclopentanos/metabolismo , Cetonas/química , Cetonas/metabolismo , Lipase/metabolismo , Enxofre/química , Candida/enzimologia , Cristalografia por Raios X , Cinética , Oxirredução , Estereoisomerismo
10.
Org Lett ; 7(1): 43-6, 2005 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-15624973

RESUMO

The facile double reduction of bicyclic aromatic sulfonamides was used to synthesize a variety of 2- and 3-aryl-substituted pyrrolidines and 2-phenylpiperidine. The method features a combined nitrogen protection and a traceless tether for the transposition of the aromatic moiety from nitrogen to carbon.

11.
J Chem Phys ; 120(3): 1402-13, 2004 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-15268266

RESUMO

The dynamical properties of ionic melts formed from mixtures of LiCl and KCl have been studied across the full composition range in computer simulations of sufficient length to enable reliable values for such collective transport coefficients as the viscosity, conductivity, and internal mobilities to be determined reliably. Interest centers on the nontrivial concentration dependence exhibited by these transport coefficients, which agrees well with that observed experimentally, and in relating this to the strength of the association between an ion and its first coordination shell. The relationships between the various transport coefficients, such as those between the diffusion coefficient and the viscosity (Stokes-Einstein) and the conductivity (Nernst-Einstein) also exhibit composition dependences that reflect this association. The connection between the internal mobility and two measures of the coordination shell dynamics (the cage relaxation time and the self-exchange velocity) is explored; it is shown that the self-exchange velocity follows the composition and temperature dependence of the internal mobility very well. Finally, it is shown that allowing for anion polarization in the interaction model increases the mobility of all species without changing the structure of the melt discernibly, with the largest effect being found for the Li(+) ion.

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