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Proper understanding of recurrent stress urinary incontinence treatment in women (PURSUIT): a randomised controlled trial of endoscopic and surgical treatment. Trials 2022; 23:628. [PMID: 35922823 PMCID: PMC9347071 DOI: 10.1186/s13063-022-06546-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 07/13/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Women with stress urinary incontinence (SUI) experience urine leakage with physical activity. Currently, the interventional treatments for SUI are surgical, or endoscopic bulking injection(s). However, these procedures are not always successful, and symptoms can persist or come back after treatment, categorised as recurrent SUI. There are longstanding symptoms and distress associated with a failed primary treatment, and currently, there is no consensus on how best to treat women with recurrent, or persistent, SUI. METHODS A two-arm trial, set in at least 20 National Health Service (NHS) urology and urogynaecology referral units in the UK, randomising 250 adult women with recurrent or persistent SUI 1:1 to receive either an endoscopic intervention (endoscopic bulking injections) or a standard NHS surgical intervention, currently colposuspension, autologous fascial sling or artificial urinary sphincter. The aim of the trial is to determine whether surgical treatment is superior to endoscopic bulking injections in terms of symptom severity at 1 year after randomisation. This primary outcome will be measured using the patient-reported International Consultation on Incontinence Questionnaire - Urinary Incontinence - Short Form (ICIQ-UI-SF). Secondary outcomes include assessment of longer-term clinical impact, improvement of symptoms, safety, operative assessments, sexual function, cost-effectiveness and an evaluation of patients' and clinicians' views and experiences of the interventions. DISCUSSION There is a lack of high-quality, randomised, scientific evidence for which treatment is best for women presenting with recurrent SUI. The PURSUIT study will benefit healthcare professionals and patients and provide robust evidence to guide further treatment and improve symptoms and quality of life for women with this condition. TRIAL REGISTRATION International Standard Randomised Controlled Trials Number (ISRCTN) registry ISRCTN12201059. Registered on 09 January 2020.
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Modelling the lifetime cost-effectiveness of radical prostatectomy, radiotherapy and active monitoring for men with clinically localised prostate cancer from median 10-year outcomes in the ProtecT randomised trial. BMC Cancer 2020; 20:971. [PMID: 33028256 PMCID: PMC7542698 DOI: 10.1186/s12885-020-07276-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 08/09/2020] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Optimal management strategies for clinically localised prostate cancer are debated. Using median 10-year data from the largest randomised controlled trial to date (ProtecT), the lifetime cost-effectiveness of three major treatments (radical radiotherapy, radical prostatectomy and active monitoring) was explored according to age and risk subgroups. METHODS A decision-analytic (Markov) model was developed and informed by clinical input. The economic evaluation adopted a UK NHS perspective and the outcome was cost per Quality-Adjusted Life Year (QALY) gained (reported in UK£), estimated using EQ-5D-3L. RESULTS Costs and QALYs extrapolated over the lifetime were mostly similar between the three randomised strategies and their subgroups, but with some important differences. Across all analyses, active monitoring was associated with higher costs, probably associated with higher rates of metastatic disease and changes to radical treatments. When comparing the value of the strategies (QALY gains and costs) in monetary terms, for both low-risk prostate cancer subgroups, radiotherapy generated the greatest net monetary benefit (£293,446 [95% CI £282,811 to £299,451] by D'Amico and £292,736 [95% CI £284,074 to £297,719] by Grade group 1). However, the sensitivity analysis highlighted uncertainty in the finding when stratified by Grade group, as radiotherapy had 53% probability of cost-effectiveness and prostatectomy had 43%. In intermediate/high risk groups, using D'Amico and Grade group > = 2, prostatectomy generated the greatest net monetary benefit (£275,977 [95% CI £258,630 to £285,474] by D'Amico and £271,933 [95% CI £237,864 to £287,784] by Grade group). This finding was supported by the sensitivity analysis. Prostatectomy had the greatest net benefit (£290,487 [95% CI £280,781 to £296,281]) for men younger than 65 and radical radiotherapy (£201,311 [95% CI £195,161 to £205,049]) for men older than 65, but sensitivity analysis showed considerable uncertainty in both findings. CONCLUSION Over the lifetime, extrapolating from the ProtecT trial, radical radiotherapy and prostatectomy appeared to be cost-effective for low risk prostate cancer, and radical prostatectomy for intermediate/high risk prostate cancer, but there was uncertainty in some estimates. Longer ProtecT trial follow-up is required to reduce uncertainty in the model. TRIAL REGISTRATION Current Controlled Trials number, ISRCTN20141297: http://isrctn.org (14/10/2002); ClinicalTrials.gov number, NCT02044172: http://www.clinicaltrials.gov (23/01/2014).
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Understanding and optimising patient and public involvement in trial oversight: an ethnographic study of eight clinical trials. Trials 2020; 21:543. [PMID: 32552907 PMCID: PMC7302397 DOI: 10.1186/s13063-020-04495-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 06/10/2020] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Trial oversight is important for trial governance and conduct. Patients and/or lay members of the public are increasingly included in trial oversight committees, influenced by international patient and public involvement (PPI) initiatives to improve the quality and relevance of research. However, there is a lack of guidance on how to undertake PPI in trial oversight and tokenistic PPI remains an issue. This paper explores how PPI functions in existing trial oversight committees and provides recommendations to optimise PPI in future trials. This was part of a larger study investigating the role and function of oversight committees in trials facing challenges. METHODS Using an ethnographic study design, we observed oversight meetings of eight UK trials and conducted semi-structured interviews with members of their trial steering committees (TSCs) and trial management groups (TMGs) including public contributors, trial sponsors and funders. Thematic analysis of data was undertaken, with findings integrated to provide a multi-perspective account of how PPI functions in trial oversight. RESULTS Eight TSC and six TMG meetings from eight trials were observed, and 66 semi-structured interviews conducted with 52 purposively sampled oversight group members, including three public contributors. PPI was reported as beneficial in trial oversight, with public members contributing a patient voice and fulfilling a patient advocacy role. However, public contributors were not always active at oversight meetings and were sometimes felt to have a tokenistic role, with trialists reporting a lack of understanding of how to undertake PPI in trial oversight. To optimise PPI in trial oversight, the following areas were highlighted: the importance of planning effective strategies to recruit public contributors; considering the level of oversight and stage(s) of trial to include PPI; support for public contributors by the trial team between and during oversight meetings. CONCLUSIONS We present evidence-based recommendations to inform future PPI in trial oversight. Consideration should be given at trial design stage on how to recruit and involve public contributors within trial oversight, as well as support and mentorship for both public contributors and trialists (in how to undertake PPI effectively). Findings from this study further strengthen the evidence base on facilitating meaningful PPI within clinical trials.
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Clinical features, biochemistry and HLA-DRB1 status in children and adolescents with diabetes in Dhaka, Bangladesh. Diabetes Res Clin Pract 2019; 158:107894. [PMID: 31669629 PMCID: PMC6988504 DOI: 10.1016/j.diabres.2019.107894] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 10/22/2019] [Indexed: 11/30/2022]
Abstract
AIMS Little information is published on diabetes in young people in Bangladesh. We aimed to investigate the demographic, clinical, and biochemical features, and HLA-DRB1 alleles in new cases of diabetes affecting Bangladeshi children and adolescents <22 years of age. METHODS The study was conducted at Bangladesh Institute of Research and Rehabilitation of Diabetes, Endocrine and Metabolic Disorders (BIRDEM) in Dhaka. One hundred subjects aged <22 years at diagnosis were enrolled. Demographic characteristics, clinical information, biochemical parameters (blood glucose, HbA1c, C-peptide, and autoantibodies against glutamic acid decarboxylase 65 (GADA) and islet antigen-2 (IA-2A) were measured. High-resolution DNA genotyping was performed for HLA-DRB1. RESULTS Eighty-four subjects were clinically diagnosed as type 1 diabetes (T1D), seven as type 2 diabetes (T2D), and nine as fibrocalculous pancreatic disease (FCPD). Of the 84 with T1D, 37 (44%) were males and 47 (56%) females, with median age at diagnosis 13 years (y) (range 1.6-21.7) and peak age at onset 12-15 years. 85% of subjects were assessed within one month of diagnosis and all within eleven months. For subjects diagnosed with T1D, mean C-peptide was 0.46 ± 0.22 nmol/L (1.40 ± 0.59 ng/mL), with 9 (10.7%) IA-2A positive, 22 (26%) GADA positive, and 5 (6%) positive for both autoantibodies. Analysis of HLA-DRB1 genotypes revealed locus-level T1D association (p = 6.0E-05); DRB1*04:01 appeared predisposing (p < 3.0E-06), and DRB1*14:01 appeared protective (p = 1.7E-02). CONCLUSIONS Atypical forms of T1D appear to be more common in young people in Bangladesh than in European populations. This will be helpful in guiding more specific assessment at onset and potentially, expanding treatment options.
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Prostate cancer risk related to foods, food groups, macronutrients and micronutrients derived from the UK Dietary Cohort Consortium food diaries. Eur J Clin Nutr 2017; 71:567. [PMID: 28294171 PMCID: PMC5383924 DOI: 10.1038/ejcn.2017.17] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Predominance of DR3 in Somali children with type 1 diabetes in the twin cities, Minnesota. Pediatr Diabetes 2017; 18:136-142. [PMID: 26854192 DOI: 10.1111/pedi.12369] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 01/08/2016] [Accepted: 01/08/2016] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Minnesota is home to the largest Somali population in USA, and pediatric diabetes teams are seeing increasing numbers of Somali children with diabetes. OBJECTIVE To assess the immune basis of diabetes in Somali children in the Twin Cities, Minnesota. METHODS A total of 31 Somali children ≤19 yr were treated for type 1 diabetes (T1D) at the University of Minnesota Masonic Children's Hospital and Children's Hospitals and Clinics of Minnesota underwent analysis of human leukocyte antigen (HLA) alleles (n = 30) and diabetes autoantibodies [glutamic acid decarboxylase (GAD65), islet antigen 2 (IA-2), zinc transporter 8 (ZnT8); n = 31]. HLA alleles were analyzed in 49 Somalis without diabetes (controls). Anti-transglutaminase autoantibodies (TGA) for celiac disease were also measured. RESULTS In Somali children with T1D aged 13.5 ± 5 yr (35% female, disease duration 6.5 ± 3.6 yr), the most common HLA allele was DRB1*03:01 (93%, compared with 45% of Somali controls), followed by DRB1*13:02 (27%). There was a relatively low frequency of DR4 (13%). Controls showed a similar pattern. All 31 participants were positive for at least one diabetes autoantibody. Insulin antibodies were positive in 84% (all were on insulin). Excluding insulin antibodies, 23 (74%) subjects tested positive for at least one other diabetes autoantibody; 32% had 1 autoantibody, 32% had 2 autoantibodies, and 10% had 3 autoantibodies. GAD65 autoantibodies were found in 56% of subjects, IA-2 in 29%, and ZnT8 in 26%. Four (13%) were TGA positive. CONCLUSION The autoantibody and HLA profiles of Somali children with diabetes are consistent with autoimmune diabetes. Their HLA profile is unique with an exceptionally high prevalence of DRB1*03:01 allele and relative paucity of DR4 alleles compared with African Americans with T1D.
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Prostate cancer risk related to foods, food groups, macronutrients and micronutrients derived from the UK Dietary Cohort Consortium food diaries. Eur J Clin Nutr 2017; 71:274-283. [PMID: 27677361 PMCID: PMC5215092 DOI: 10.1038/ejcn.2016.162] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 04/29/2016] [Accepted: 07/14/2016] [Indexed: 01/08/2023]
Abstract
BACKGROUND/OBJECTIVES The influence of dietary factors remains controversial for screen-detected prostate cancer and inconclusive for clinically detected disease. We aimed to examine these associations using prospectively collected food diaries. SUBJECTS/METHODS A total of 1,717 prostate cancer cases in middle-aged and older UK men were pooled from four prospective cohorts with clinically detected disease (n=663), with routine data follow-up (means 6.6-13.3 years) and a case-control study with screen-detected disease (n=1054), nested in a randomised trial of prostate cancer treatments (ISCTRN 20141297). Multiple-day food diaries (records) completed by men prior to diagnosis were used to estimate intakes of 37 selected nutrients, food groups and items, including carbohydrate, fat, protein, dairy products, fish, meat, fruit and vegetables, energy, fibre, alcohol, lycopene and selenium. Cases were matched on age and diary date to at least one control within study (n=3528). Prostate cancer risk was calculated, using conditional logistic regression (adjusted for baseline covariates) and expressed as odds ratios in each quintile of intake (±95% confidence intervals). Prostate cancer risk was also investigated by localised or advanced stage and by cancer detection method. RESULTS There were no strong associations between prostate cancer risk and 37 dietary factors. CONCLUSIONS Prostate cancer risk, including by disease stage, was not strongly associated with dietary factors measured by food diaries in middle-aged and older UK men.
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Abstract
BACKGROUND Robust data on patient-reported outcome measures comparing treatments for clinically localized prostate cancer are lacking. We investigated the effects of active monitoring, radical prostatectomy, and radical radiotherapy with hormones on patient-reported outcomes. METHODS We compared patient-reported outcomes among 1643 men in the Prostate Testing for Cancer and Treatment (ProtecT) trial who completed questionnaires before diagnosis, at 6 and 12 months after randomization, and annually thereafter. Patients completed validated measures that assessed urinary, bowel, and sexual function and specific effects on quality of life, anxiety and depression, and general health. Cancer-related quality of life was assessed at 5 years. Complete 6-year data were analyzed according to the intention-to-treat principle. RESULTS The rate of questionnaire completion during follow-up was higher than 85% for most measures. Of the three treatments, prostatectomy had the greatest negative effect on sexual function and urinary continence, and although there was some recovery, these outcomes remained worse in the prostatectomy group than in the other groups throughout the trial. The negative effect of radiotherapy on sexual function was greatest at 6 months, but sexual function then recovered somewhat and was stable thereafter; radiotherapy had little effect on urinary continence. Sexual and urinary function declined gradually in the active-monitoring group. Bowel function was worse in the radiotherapy group at 6 months than in the other groups but then recovered somewhat, except for the increasing frequency of bloody stools; bowel function was unchanged in the other groups. Urinary voiding and nocturia were worse in the radiotherapy group at 6 months but then mostly recovered and were similar to the other groups after 12 months. Effects on quality of life mirrored the reported changes in function. No significant differences were observed among the groups in measures of anxiety, depression, or general health-related or cancer-related quality of life. CONCLUSIONS In this analysis of patient-reported outcomes after treatment for localized prostate cancer, patterns of severity, recovery, and decline in urinary, bowel, and sexual function and associated quality of life differed among the three groups. (Funded by the U.K. National Institute for Health Research Health Technology Assessment Program; ProtecT Current Controlled Trials number, ISRCTN20141297 ; ClinicalTrials.gov number, NCT02044172 .).
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Hypomethylation within gene promoter regions and type 1 diabetes in discordant monozygotic twins. J Autoimmun 2016; 68:23-9. [PMID: 26782299 DOI: 10.1016/j.jaut.2015.12.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2015] [Revised: 12/04/2015] [Accepted: 12/10/2015] [Indexed: 02/08/2023]
Abstract
Genetic susceptibility to type 1 diabetes (T1D) is well supported by epidemiologic evidence; however, disease risk cannot be entirely explained by established genetic variants identified so far. This study addresses the question of whether epigenetic modification of the inherited DNA sequence may contribute to T1D susceptibility. Using the Infinium HumanMethylation450 BeadChip array (450k), a total of seven long-term disease-discordant monozygotic (MZ) twin pairs and five pairs of HLA-identical, disease-discordant non-twin siblings (NTS) were examined for associations between DNA methylation (DNAm) and T1D. Strong evidence for global hypomethylation of CpG sites within promoter regions in MZ twins with TID compared to twins without T1D was observed. DNA methylation data were then grouped into three categories of CpG sites for further analysis, including those within: 1) the major histocompatibility complex (MHC) region, 2) non-MHC genes with reported T1D association through genome wide association studies (GWAS), and 3) the epigenome, or remainder of sites that did not include MHC and T1D associated genes. Initial results showed modest methylation differences between discordant MZ twins for the MHC region and T1D-associated CpG sites, BACH2, INS-IGF2, and CLEC16A (DNAm difference range: 2.2%-5.0%). In the epigenome CpG set, the greatest methylation differences were observed in MAGI2, FANCC, and PCDHB16, (DNAm difference range: 6.9%-16.1%). These findings were not observed in the HLA-identical NTS pairs. Targeted pyrosequencing of five candidate CpG loci identified using the 450k array in the original discordant MZ twins produced similar results using control DNA samples, indicating strong agreement between the two DNA methylation profiling platforms. However, findings for the top five candidate CpG loci were not replicated in six additional T1D-discordant MZ twin pairs. Our results indicate global DNA hypomethylation within gene promoter regions may contribute to T1D; however, findings do not support the involvement of large DNAm differences at single CpG sites alone in T1D.
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Urodynamics for Prostate Surgery Trial; Randomised Evaluation of Assessment Methods (UPSTREAM) for diagnosis and management of bladder outlet obstruction in men: study protocol for a randomised controlled trial. Trials 2015; 16:567. [PMID: 26651344 PMCID: PMC4676182 DOI: 10.1186/s13063-015-1087-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 11/26/2015] [Indexed: 11/17/2022] Open
Abstract
Background Lower urinary tract symptoms (LUTS) comprise storage symptoms, voiding symptoms and post-voiding symptoms. Prevalence and severity of LUTS increase with age and the progressive increase in the aged population group has emphasised the importance to our society of appropriate and effective management of male LUTS. Identification of causal mechanisms is needed to optimise treatment and uroflowmetry is the simplest non-invasive test of voiding function. Invasive urodynamics can evaluate storage function and voiding function; however, there is currently insufficient evidence to support urodynamics becoming part of routine practice in the clinical evaluation of male LUTS. Design A 2-arm trial, set in urology departments of at least 26 National Health Service (NHS) hospitals in the United Kingdom (UK), randomising men with bothersome LUTS for whom surgeons would consider offering surgery, between a care pathway based on urodynamic tests with invasive multichannel cystometry and a care pathway based on non-invasive routine tests. The aim of the trial is to determine whether a care pathway not including invasive urodynamics is no worse for men in terms of symptom outcome than one in which it is included, at 18 months after randomisation. This primary clinical outcome will be measured with the International Prostate Symptom Score (IPSS). We will also establish whether inclusion of invasive urodynamics reduces rates of bladder outlet surgery as a main secondary outcome. Discussion The general population has an increased life-expectancy and, as men get older, their prostates enlarge and potentially cause benign prostatic obstruction (BPO) which often requires surgery. Furthermore, voiding symptoms become increasingly prevalent, some of which may not be due to BPO. Therefore, as the population ages, more operations will be considered to relieve BPO, some of which may not actually be appropriate. Hence, there is sustained interest in the diagnostic pathway and this trial could improve the chances of an accurate diagnosis and reduce overall numbers of surgical interventions for BPO in the NHS. The morbidity, and therapy costs, of testing must be weighed against the cost saving of surgery reduction. Trial registration Controlled-trials.com - ISRCTN56164274 (confirmed registration: 8 April 2014). Electronic supplementary material The online version of this article (doi:10.1186/s13063-015-1087-1) contains supplementary material, which is available to authorized users.
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Enhancing public involvement in trial oversight committees through qualitative research with eight trials facing challenges. Trials 2015. [PMCID: PMC4660224 DOI: 10.1186/1745-6215-16-s2-p78] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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KIR haplotypes are associated with late-onset type 1 diabetes in European-American families. Genes Immun 2015; 17:8-12. [PMID: 26492518 PMCID: PMC4746488 DOI: 10.1038/gene.2015.44] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 09/14/2015] [Accepted: 09/15/2015] [Indexed: 01/30/2023]
Abstract
Classical human leukocyte antigens (HLA) genes confer the strongest, but not the only, genetic susceptibility to type 1 diabetes. Killer cell immunoglobulin-like receptors (KIR), on natural killer (NK) cells, bind ligands including class I HLA. We examined presence or absence, with copy number, of KIR loci in 1698 individuals, from 339 multiplex type 1 diabetes families, from the Human Biological Data Interchange, previously genotyped for HLA. Combining family data with KIR copy number information allowed assignment of haplotypes using identity by descent. This is the first disease study to use KIR copy number typing and unambiguously define haplotypes by gene transmission. KIR A1 haplotypes were positively associated with T1D in the subset of patients without the high T1D risk HLA genotype, DR3/DR4 (odds ratio=1.29, P=0.0096). The data point to a role for KIR in type 1 diabetes risk in late-onset patients. In the top quartile (age of onset>14), KIR A2 haplotype was overtransmitted (63.4%, odds ratio=1.73, P=0.024) and KIR B haplotypes were undertransmitted (41.1%, odds ratio=0.70, P=0.0052) to patients. The data suggest that inhibitory ‘A' haplotypes are predisposing and stimulatory ‘B' haplotypes confer protection in both DR3/DR4-negative and late-onset patient groups.
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Concordance of next generation sequence-based and sequence specific oligonucleotide probe-based HLA-DRB1 genotyping. Hum Immunol 2015; 76:939-44. [PMID: 26247828 DOI: 10.1016/j.humimm.2015.07.235] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Revised: 07/28/2015] [Accepted: 07/31/2015] [Indexed: 11/25/2022]
Abstract
Next generation sequencing (NGS) of clonally amplified DNA, using Roche 454 technology, was used to genotype HLA-DRB1, DRB3, DRB4, and DRB5 loci (exon 2 only) from a set of 993 samples from newborns with maternally-reported African American ancestry. DRB1 exon 2 was genotyped previously on the same sample set using sequence-specific oligonucleotide probe (SSOP) technology. Comparison of the genotype calls from both methods indicated concordance of 92.3%. Some discordance was expected due to the higher resolution of NGS data, compared to SSOP data. This resulted from selection of the incorrect allele from the ambiguity string produced by SSOP genotyping. Of 76 discordant genotypes, only three were due to resolution of ambiguity with the NGS method. The low percent of changes due to the increased resolution of the NGS method instills confidence in the overall value of previous data genotyped with moderate resolution methods, i.e., the vast majority of alleles present in a population are those that are detectable at moderate resolution. The remaining 73 discordant genotypes resulted from preventable errors in sample handling, data interpretation, and data entry. These results underscore the potential for error that can result from factors such as low quality genomic DNA, manual data entry, and interpretation of marginal genotyping results. Optimization of genomic DNA quality, automation of genotyping steps wherever possible, and use of the highest resolution technology available can lead to dramatic improvements in HLA genotype data quality. NGS-based methodology generated data of superior quality and accuracy compared to the SSOP system.
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Vermicious thermo-responsive Pickering emulsifiers. Chem Sci 2015; 6:4207-4214. [PMID: 29218187 PMCID: PMC5707463 DOI: 10.1039/c5sc00598a] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 05/07/2015] [Indexed: 02/05/2023] Open
Abstract
Thermo-responsive vermicious (or worm-like) diblock copolymer nanoparticles prepared directly in n-dodecane are used to stabilise water-in-oil Pickering emulsions.
Thermo-responsive vermicious (or worm-like) diblock copolymer nanoparticles prepared directly in n-dodecane via polymerisation-induced self-assembly (PISA) were used to stabilise water-in-oil Pickering emulsions. Mean droplet diameters could be tuned from 8 to 117 μm by varying the worm copolymer concentration and the water volume fraction and very high worm adsorption efficiencies (∼100%) could be obtained below a certain critical copolymer concentration (∼0.50%). Heating a worm dispersion up to 150 °C led to a worm-to-sphere transition, which proved to be irreversible if conducted at sufficiently low copolymer concentration. This affords a rare opportunity to directly compare the Pickering emulsifier performance of chemically identical worms and spheres. It is found that the former nanoparticles are markedly more efficient, since worm-stabilised water droplets are always smaller than the equivalent sphere-stabilised droplets prepared under identical conditions. Moreover, the latter emulsions are appreciably flocculated, whereas the former emulsions proved to be stable. SAXS studies indicate that the mean thickness of the adsorbed worm layer surrounding the water droplets is comparable to that of the worm cross-section diameter determined for non-adsorbed worms dispersed in the continuous phase. Thus the adsorbed worms form a monolayer shell around the water droplets, rather than ill-defined multilayers. Under certain conditions, demulsification occurs on heating as a result of a partial worm-to-sphere morphological transition.
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LBP25. Hum Immunol 2015. [DOI: 10.1016/j.humimm.2015.01.057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Prevalence of the HOXB13 G84E germline mutation in British men and correlation with prostate cancer risk, tumour characteristics and clinical outcomes. Ann Oncol 2015; 26:756-761. [PMID: 25595936 DOI: 10.1093/annonc/mdv004] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND A rare recurrent missense variant in HOXB13 (rs138213197/G84E) was recently reported to be associated with hereditary prostate cancer. Population-based studies have established that, since the frequency of this single-nucleotide polymorphism (SNP) varies between geographic regions, the associated proportion of prostate cancer (PrCa) risk contribution is also highly variable by country. PATIENTS AND METHODS This is the largest comprehensive case-control study assessing the prevalence of the HOXB13 G84E variant to date and is the first in the UK population. We genotyped 8652 men diagnosed with PrCa within the UK Genetic Prostate Cancer Study (UKGPCS) and 5252 healthy men from the UK ProtecT study. RESULTS HOXB13 G84E was identified in 0.5% of the healthy controls and 1.5% of the PrCa cases, and it was associated with a 2.93-fold increased risk of PrCa [95% confidence interval (CI) 1.94-4.59; P = 6.27 × 10(-8)]. The risk was even higher among men with family history of PrCa [odds ratio (OR) = 4.53, 95% CI 2.86-7.34; P = 3.1 × 10(-8)] and in young-onset PrCa (diagnosed up to the age of 55 years; OR = 3.11, 95% CI 1.98-5.00; P = 6.1 × 10(-7)). There was no significant association between Gleason Score, presenting prostate specific antigen, tumour-node-metastasis (TNM) stage or NCCN risk group and carrier status. HOXB13 G84E was not associated with overall or cancer-specific survival. We found that the polygenic PrCa risk score (PR score), calculated using the 71 known single-nucleotide polymorphisms (SNPs) associated with PrCa and the HOXB13 G84E variant act multiplicatively on PrCa risk. Based on the estimated prevalence and risk, this rare variant explains ∼1% of the familial risk of PrCa in the UK population. CONCLUSIONS The clinical importance of HOXB13 G84E in PrCa management has not been established. This variant was found to have no effect on prognostic implications but could be used for stratifying screening, by identifying men at high risk. CLINICAL TRIALS NUMBERS Prostate Testing for Cancer and Treatment (ProtecT): NCT02044172. UK GENETIC PROSTATE CANCER STUDY Epidemiology and Molecular Genetics Studies (UKGPCS): NCT01737242.
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Design and preliminary recruitment results of the Cluster randomised triAl of PSA testing for Prostate cancer (CAP). Br J Cancer 2014; 110:2829-36. [PMID: 24867688 PMCID: PMC4056057 DOI: 10.1038/bjc.2014.242] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Revised: 04/08/2014] [Accepted: 04/10/2014] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND Screening for prostate cancer continues to generate controversy because of concerns about over-diagnosis and unnecessary treatment. We describe the rationale, design and recruitment of the Cluster randomised triAl of PSA testing for Prostate cancer (CAP) trial, a UK-wide cluster randomised controlled trial investigating the effectiveness and cost-effectiveness of prostate-specific antigen (PSA) testing. METHODS Seven hundred and eighty-five general practitioner (GP) practices in England and Wales were randomised to a population-based PSA testing or standard care and then approached for consent to participate. In the intervention arm, men aged 50-69 years were invited to undergo PSA testing, and those diagnosed with localised prostate cancer were invited into a treatment trial. Control arm practices undertook standard UK management. All men were flagged with the Health and Social Care Information Centre for deaths and cancer registrations. The primary outcome is prostate cancer mortality at a median 10-year-follow-up. RESULTS Among randomised practices, 271 (68%) in the intervention arm (198,114 men) and 302 (78%) in the control arm (221,929 men) consented to participate, meeting pre-specified power requirements. There was little evidence of differences between trial arms in measured baseline characteristics of the consenting GP practices (or men within those practices). CONCLUSIONS The CAP trial successfully met its recruitment targets and will make an important contribution to international understanding of PSA-based prostate cancer screening.
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Abstract
HLA genotyping was performed in African American type 1 diabetic patients (n = 772) and controls (n = 1,641) in the largest study of African Americans and type 1 diabetes reported to date. Cases were from Children's Hospital and Research Center Oakland and from existing collections (Type 1 Diabetes Genetics Consortium [T1DGC], Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications [DCCT/EDIC], and Genetics of Kidneys in Diabetes [GoKinD]). Controls were from the T1DGC and from newborn bloodspot cards. The diversity of HLA DRB1-DQA1-DQB1 haplotypes and genotypes is far greater than that found in Europeans and European Americans. Association analyses replicated many type 1 diabetes risk effects of European-derived haplotypes but also revealed novel effects for African-derived haplotypes. Notably, the African-specific "DR3" haplotype DRB1*03:02-DQA1*04:01-DQB1*04:02 is protective for type 1 diabetes, in contrast to the common and highly-susceptible DR3 DRB1*03:01-DQA1*05:01-DQB1*02:01. Both DRB1*07:01 and DRB1*13:03 haplotypes are predisposing when they include DQA1*03:01-DQB1*02:01g but are protective with DQA1*02:01-DQB1*02:01g. The heterozygous DR4/DR9 genotype, containing the African-derived "DR9" haplotype DRB1*09:01-DQA1*03:01-DQB1*02:01g, exhibits extremely high risk (odds ratio = 30.88), approaching that for DR3/DR4 in European populations. Disease risk assessment for African Americans differs greatly from risk assessment in European populations. This has profound implications on risk screening programs and underscores the need for high-resolution genotyping of multiple populations for the rational design of screening programs with tests that will fairly represent the population being screened.
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PS05 Men With Prostate Cancer Make Positive Dietary Changes Following Treatment in a Randomised Trial: A Prospective Cohort Study. Br J Soc Med 2012. [DOI: 10.1136/jech-2012-201753.104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Abstract
The aim of this study was to test the hypothesis that closely related human leukocyte antigen (HLA) haplotypes containing the DRB1*07:01 gene ['DR7' (DRB1*07:01-DQA1*02:01-DQB1*02:01g or DRB1*07:01-DQA1*03:01-DQB1*02:01g) haplotypes] derived from European and African populations differ in their genetic susceptibility for type 1 diabetes (T1D) depending on the DQ-α molecule present. A combined total of 98 African American T1D patients from the Type 1 Diabetes Genetics Consortium and from Children's Hospital and Research Center Oakland were genotyped for the HLA class II loci DRB1, DQA1, and DQB1. DNA samples extracted from newborn blood spot cards from African Americans born in California (n = 947) were used as a population-based control group. Among African American cases, the European-derived DRB1*07:01-DQA1*02:01-DQB1*02:01g haplotype was protective for T1D risk (odds ratio (OR) = 0.34; 95% confidence interval (CI) 0.14-0.78; P < 0.011), but the African-derived DRB1*07:01-DQA1*03:01-DQB1*02:01g haplotype increased T1D risk (OR = 3.96; 95% CI 1.94-8.08; P < 5.5E-05). The effect of DRB1*07:01-DQB1*02:01g on T1D susceptibility depends on the DQA1 allele. DRB1*07:01-DQA1*02:01-DQB1*02:01g is protective for T1D; however, the presence of DQA1*03:01 on the DRB1*07:01-DQB1*02:01g haplotype not only renders the DR7 haplotype not protective but also creates a haplotype with significant T1D risk. These data underscore the importance of assessing genetic effects within ethnic context.
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204-P DRB1*07:01 increases risk for bacterial vaginosis in black women. Hum Immunol 2011. [DOI: 10.1016/j.humimm.2011.07.229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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The rs4774 CIITA missense variant is associated with risk of systemic lupus erythematosus. Genes Immun 2011; 12:667-71. [PMID: 21614020 DOI: 10.1038/gene.2011.36] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The major histocompatibility complex (MHC) class II transactivator gene (CIITA) encodes an important transcription factor required for human leukocyte antigens (HLA) class II MHC-restricted antigen presentation. MHC genes, including the HLA class II DRB1*03:01 allele, are strongly associated with systemic lupus erythematosus (SLE). Recently the rs4774 CIITA missense variant (+1632G/C) was reported to be associated with susceptibility to multiple sclerosis. In the current study, we investigated CIITA, DRB1*03:01 and risk of SLE using a multi-stage analysis. In stage 1, 9 CIITA variants were tested in 658 cases and 1363 controls (N=2021). In stage 2, rs4774 was tested in 684 cases and 2938 controls (N=3622). We also performed a meta-analysis of the pooled 1342 cases and 4301 controls (N=5643). In stage 1, rs4774(*)C was associated with SLE (odds ratio (OR)=1.24, 95% confidence interval (95% CI)=1.07-1.44, P=4.2 × 10(-3)). Similar results were observed in stage 2 (OR=1.16, 95% CI=1.02-1.33, P=8.5 × 10(-3)) and the meta-analysis of the combined data set (OR=1.20, 95% CI=1.09-1.33, P(meta)=2.5 × 10(-4)). In all three analyses, the strongest evidence for association between rs4774(*)C and SLE was present in individuals who carried at least one copy of DRB1*03:01 (P(meta)=1.9 × 10(-3)). Results support a role for CIITA in SLE, which appears to be stronger in the presence of DRB1*03:01.
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Latest results from the UK trials evaluating prostate cancer screening and treatment: the CAP and ProtecT studies. Eur J Cancer 2011; 46:3095-101. [PMID: 21047592 DOI: 10.1016/j.ejca.2010.09.016] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2010] [Revised: 08/11/2010] [Accepted: 09/07/2010] [Indexed: 11/19/2022]
Abstract
The European Randomised Study of Screening for Prostate Cancer (ERSPC) demonstrated a significant reduction in prostate cancer-specific mortality. The ongoing Comparison Arm for ProtecT (CAP) cluster randomised controlled trial (RCT) evaluates prostate cancer screening effectiveness by comparing primary care centres allocated to a round of prostate specific antigen (PSA) testing (intervention) or standard clinical care. Over 550 centres (around 450,000 men) were randomised in eight United Kingdom areas (2002-2008). Intervention group participants were also eligible for the ProtecT (Prostate testing for cancer and Treatment) RCT evaluating active monitoring, radiotherapy and radical prostatectomy treatments for localised prostate cancer. In ProtecT, over 1500 of around 3000 men with prostate cancer were randomised from over 10,000 with an elevated PSA in around 111,000 attendees at clinics. Investigation of the psychological impact of screening in a sub-sample showed that 10% of men still experienced high distress up to 3 months following prostate biopsies (22/227), although most were relatively unaffected. The risk of prostate cancer with a raised PSA was lower if urinary symptoms were present (frequent nocturia odds ratio (OR) 0.44, 95% confidence interval (CI) 0.22-0.83) or if a repeat PSA decreased by > or = 20% prior to biopsy (OR 0.43, 95% CI 0.35-0.52). Men aged 45-49 years attended PSA clinics less frequently (442/1299, 34%) in a nested cohort with a cancer detection rate of 2.3% (10/442). The CAP and ProtecT trials (ISRCTN92187251 and ISRCTN20141217) will help resolve the prostate cancer screening debate, define the optimum treatment for localised disease and generate evidence to improve men's health.
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Randomised clinical trial: Helicobacter pylori eradication is associated with a significantly increased body mass index in a placebo-controlled study. Aliment Pharmacol Ther 2011; 33:922-9. [PMID: 21366634 DOI: 10.1111/j.1365-2036.2011.04610.x] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Body mass index (BMI) increased following Helicobacter pylori eradication in several Japanese cohorts, which requires further investigation. AIM To determine the impact of H. pylori eradication on BMI in a European population. METHODS A total of 10,537 unselected people aged 20-59 years were screened for H. pylori; 1558 of the 1634 infected participants were randomised to intervention (eradication therapy: ranitidine bismuth citrate 400 mg and clarithromycin 500 mg twice daily) or placebo for 2 weeks with follow-up at 6 months (92%) for weight and dyspepsia symptoms (epigastric pain). RESULTS The mean weight of participants in the intervention group increased from 77.7 kg at baseline to 78.4 kg at 6 months (unadjusted increase of 0.7 kg) and from 76.8 to 77.2 kg (0.5 kg) in the placebo group. The adjusted difference between randomised groups was statistically significant at 0.6 kg [95% confidence interval (CI) 0.31, 0.88]. Significantly, more participants gained ≥3 kg in the intervention group (138/720, 19%) compared with the placebo group (92/706, 13%) [odds ratio (OR) 1.57 (95% CI: 1.17, 2.12)]. The mean BMI increased from 27.5 to 27.8 kg/m(2) at 6 months in the intervention group compared with the increase from 27.0 to 27.2 kg/m(2) in the placebo group [adjusted difference between groups was statistically significant at 0.2 kg/m(2) (95% CI: 0.11, 0.31)]. Dyspepsia was less frequently reported by intervention group participants (168/736, 23%, placebo group 209/711, 29%), OR 0.71 (95% CI: 0.55, 0.93). CONCLUSION Body mass index increased significantly following randomisation to H. pylori eradication therapy, possibly due to resolution of dyspepsia.
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Association of obesity with prostate cancer: a case-control study within the population-based PSA testing phase of the ProtecT study. Br J Cancer 2011; 104:875-81. [PMID: 21266978 PMCID: PMC3048201 DOI: 10.1038/sj.bjc.6606066] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Background: Obesity has been inconsistently linked to prostate cancer, mainly with mortality rather than incidence. Few large-scale studies exist assessing obesity in relation to prostate-specific antigen (PSA)-detected prostate cancer. Methods: We used cases and stratum-matched controls from the population-based PSA-testing phase of the Prostate testing for cancer and Treatment study to examine the hypothesis that obesity as measured by body mass index (BMI), waist circumference and waist-to-hip ratio (WHR) is associated with increased prostate cancer risk, and with higher tumour stage and grade. In all, 2167 eligible cases and 11 638 randomly selected eligible controls with PSA values were recruited between 2001 and 2008. A maximum of 960 cases and 4156 controls had measurement data, and also complete data on age and family history, and were included in the final analysis. BMI was categorised as <25.0, 25.0–29.9, ⩾30.0 in kg m−2. Results: Following adjustment for age and family history of prostate cancer, we found little evidence that BMI was associated with total prostate cancer (odds ratio (OR): 0.83, 95% confidence interval (CI): 0.67, 1.03; highest vs lowest tertile; P-trend 0.1). A weak inverse association was evident for low-grade (OR: 0.76, 95% CI: 0.59, 0.97; highest vs lowest tertile; P-trend 0.045) prostate cancer. We found no association of either waist circumference (OR: 0.94, 95% CI: 0.80, 1.12; highest vs lowest tertile) or waist-to-hip ratio (WHR; OR: 0.93, 95% CI: 0.77, 1.11; highest vs lowest tertile) with total prostate cancer, and in analyses stratified by disease stage (all P-trend>0.35) or grade (all P-trend>0.16). Conclusion: General adiposity, as measured by BMI, was associated with a decreased risk of low-grade PSA-detected prostate cancer. However, effects were small and the confidence intervals had limits very close to one. Abdominal obesity (as measured by WHR/waist circumference) was not associated with PSA-detected prostate cancer.
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Abstract
OBJECTIVE We report here genotyping data and type 1 diabetes association analyses for HLA class I loci (A, B, and C) on 1,753 multiplex pedigrees from the Type 1 Diabetes Genetics Consortium (T1DGC), a large international collaborative study. RESEARCH DESIGN AND METHODS Complete eight-locus HLA genotyping data were generated. Expected patient class I (HLA-A, -B, and -C) allele frequencies were calculated, based on linkage disequilibrium (LD) patterns with observed HLA class II DRB1-DQA1-DQB1 haplotype frequencies. Expected frequencies were compared to observed allele frequencies in patients. RESULTS Significant type 1 diabetes associations were observed at all class I HLA loci. After accounting for LD with HLA class II, the most significantly type 1 diabetes-associated alleles were B*5701 (odds ratio 0.19; P = 4 × 10(-11)) and B*3906 (10.31; P = 4 × 10(-10)). Other significantly type 1 diabetes-associated alleles included A*2402, A*0201, B*1801, and C*0501 (predisposing) and A*1101, A*3201, A*6601, B*0702, B*4403, B*3502, C*1601, and C*0401 (protective). Some alleles, notably B*3906, appear to modulate the risk of all DRB1-DQA1-DQB1 haplotypes on which they reside, suggesting a class I effect that is independent of class II. Other class I type 1 diabetes associations appear to be specific to individual class II haplotypes. Some apparent associations (e.g., C*1601) could be attributed to strong LD to another class I susceptibility locus (B*4403). CONCLUSIONS These data indicate that HLA class I alleles, in addition to and independently from HLA class II alleles, are associated with type 1 diabetes.
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Clinical trial: prolonged beneficial effect of Helicobacter pylori eradication on dyspepsia consultations - the Bristol Helicobacter Project. Aliment Pharmacol Ther 2010; 32:394-400. [PMID: 20491744 DOI: 10.1111/j.1365-2036.2010.04363.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
BACKGROUND Chronic infection of the stomach with Helicobacter pylori is widespread throughout the world and is the major cause of peptic ulcer disease and gastric cancer. Short-term benefit results from community programmes to eradicate the infection, but there is little information on cumulative long-term benefit. AIM To determine whether a community programme of screening for and eradication of H. pylori infection produces further benefit after an initial 2-year period, as judged by a reduction in GP consultations for dyspepsia. METHODS A total of 1517 people aged 20-59 years, who were registered with seven general practices in Frenchay Health District, Bristol, had a positive (13)C-urea breath test for H. pylori infection and were entered into a randomized double-blind trial of H. pylori eradication therapy. After 2 years, we found a 35% reduction in GP consultations for dyspepsia (previously reported). In this extension to the study, we analysed dyspepsia consultations between two and 7 years after treatment. RESULTS Between two and 7 years after treatment, 81/764 (10.6%) of participants randomized to receive active treatment consulted for dyspepsia, compared with 106/753 (14.1%) of those who received placebo, a 25% reduction, odds ratio 0.84 (0.71, 1.00), P = 0.042. CONCLUSIONS Eradication of H. pylori infection in the community gives cumulative long-term benefit, with a continued reduction in the development of dyspepsia severe enough to require a consultation with a general practitioner up to at least 7 years. The cost savings resulting from this aspect of a community H. pylori eradication programme, in addition to the other theoretical benefits, make such programmes worthy of serious consideration, particularly in populations with a high prevalence of H. pylori infection.
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Abstract
Background Although human leukocyte antigen (HLA) DQ and
DR loci appear to confer the strongest genetic risk for
type 1 diabetes, more detailed information is required for other loci within the
HLA region to understand causality and stratify additional risk factors. The
Type 1 Diabetes Genetics Consortium (T1DGC) study design included
high-resolution genotyping of HLA-A, B,
C, DRB1, DQ, and
DP loci in all affected sibling pair and trio families, and
cases and controls, recruited from four networks worldwide, for analysis with
clinical phenotypes and immunological markers. Purpose In this article, we present the operational strategy of training,
classification, reporting, and quality control of HLA genotyping in four
laboratories on three continents over nearly 5 years. Methods Methods to standardize HLA genotyping at eight loci included: central
training and initial certification testing; the use of uniform reagents,
protocols, instrumentation, and software versions; an automated data transfer;
and the use of standardized nomenclature and allele databases. We implemented a
rigorous and consistent quality control process, reinforced by repeated
workshops, yearly meetings, and telephone conferences. Results A total of 15,246 samples have been HLA genotyped at eight loci to
four-digit resolution; an additional 6797 samples have been HLA genotyped at two
loci. The genotyping repeat rate decreased significantly over time, with an
estimated unresolved Mendelian inconsistency rate of 0.21%. Annual
quality control exercises tested 2192 genotypes (4384 alleles) and achieved
99.82% intra-laboratory and 99.68% inter-laboratory
concordances. Limitations The chosen genotyping platform was unable to distinguish many allele
combinations, which would require further multiple stepwise testing to resolve.
For these combinations, a standard allele assignment was agreed upon, allowing
further analysis if required. Conclusions High-resolution HLA genotyping can be performed in multiple laboratories
using standard equipment, reagents, protocols, software, and communication to
produce consistent and reproducible data with minimal systematic error. Many of
the strategies used in this study are generally applicable to other large
multi-center studies.
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Analysis of maternal-offspring HLA compatibility, parent-of-origin effects, and noninherited maternal antigen effects for HLA-DRB1 in systemic lupus erythematosus. ACTA ACUST UNITED AC 2010; 62:1712-7. [PMID: 20191587 DOI: 10.1002/art.27426] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE Genetic susceptibility to systemic lupus erythematosus (SLE) is well established, with the HLA class II DRB1 and DQB1 loci demonstrating the strongest association. However, HLA may also influence SLE through novel biologic mechanisms in addition to genetic transmission of risk alleles. Evidence for increased maternal-offspring HLA class II compatibility in SLE and differences in maternal versus paternal transmission rates (parent-of-origin effects) and nontransmission rates (noninherited maternal antigen [NIMA] effects) in other autoimmune diseases have been reported. Thus, we investigated maternal-offspring HLA compatibility, parent-of-origin effects, and NIMA effects at DRB1 in SLE. METHODS The cohort comprised 707 SLE families and 188 independent healthy maternal-offspring pairs (total of 2,497 individuals). Family-based association tests were conducted to compare transmitted versus nontransmitted alleles (transmission disequilibrium test) and both maternally versus paternally transmitted (parent-of-origin) and nontransmitted alleles (using the chi-square test of heterogeneity). Analyses were stratified according to the sex of the offspring. Maternally affected offspring DRB1 compatibility in SLE families was compared with paternally affected offspring compatibility and with independent control maternal-offspring pairs (using Fisher's test) and was restricted to male and nulligravid female offspring with SLE. RESULTS As expected, DRB1 was associated with SLE (P < 1 x 10(-4)). However, mothers of children with SLE had similar transmission and nontransmission frequencies for DRB1 alleles when compared with fathers, including those for the known SLE risk alleles HLA-DRB1*0301, *1501, and *0801. No association between maternal-offspring compatibility and SLE was observed. CONCLUSION Maternal-offspring HLA compatibility, parent-of-origin effects, and NIMA effects at DRB1 are unlikely to play a role in SLE.
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Impact of prostate cancer testing: an evaluation of the emotional consequences of a negative biopsy result. Br J Cancer 2010; 102:1335-40. [PMID: 20372151 PMCID: PMC2865757 DOI: 10.1038/sj.bjc.6605648] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Revised: 03/04/2010] [Accepted: 03/17/2010] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND When testing for prostate cancer, as many as 75% of men with a raised prostate-specific antigen (PSA) have a benign biopsy result. Little is known about the psychological effect of this result for these men. METHODS In all, 330 men participating in the prostate testing for cancer and treatment (ProtecT) study were studied; aged 50-69 years with a PSA level of > or = 3 ng ml(-1) and a negative biopsy result. Distress and negative mood were measured at four time-points: two during diagnostic testing and two after a negative biopsy result. RESULTS The majority of men were not greatly affected by testing or a negative biopsy result. The impact on psychological health was highest at the time of the biopsy, with around 20% reporting high distress (33 out of 171) and tense/anxious moods (35 out of 180). Longitudinal analysis on 195 men showed a significant increase in distress at the time of the biopsy compared with levels at the PSA test (difference in Impact of Events Scale (IES) score: 9.47; 95% confidence interval (CI) (6.97, 12.12); P<0.001). These levels remained elevated immediately after the negative biopsy result (difference in score: 7.32; 95% CI (5.51, 9.52); P<0.001) and 12 weeks later (difference in score: 2.42; 95% CI (0.50, 1.15); P=0.009). Psychological mood at the time of PSA testing predicted high levels of distress and anxiety at subsequent time-points. CONCLUSIONS Most men coped well with the testing process, although a minority experienced elevated distress at the time of biopsy and after a negative result. Men should be informed of the risk of distress relating to diagnostic uncertainty before they consent to PSA testing.
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Abstract
BACKGROUND One source of deoxyribonucleic acid (DNA) for genetic studies is the utilization of dried blood spots stored on paper cards (Guthrie cards) collected shortly after birth. These cards represent an important source of material for epidemiologic and population-based genetic studies. Extraction of DNA from these cards can lead to variable amounts of recovered DNA. We report here results of our efforts to maximize yield from this valuable, but nonrenewable, resource. METHOD Commercial methods of DNA extraction from blood cards were used, and protocol modifications were introduced that enhanced DNA yield. RESULTS Use of a commercial solvent prior to DNA extraction steps gave greater yields than extraction without the solvent. Modification of the elution step by use of prewarmed extraction buffer and a soaking step at an elevated temperature increased yield by 6- to 10-fold. CONCLUSIONS The modified DNA extraction method yielded as much as 660 ng of DNA from a single 5-mm-diameter punch of a blood spot card. The DNA performed well in downstream, polymerase chain reaction-based applications.
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High-density SNP screening of the major histocompatibility complex in systemic lupus erythematosus demonstrates strong evidence for independent susceptibility regions. PLoS Genet 2009; 5:e1000696. [PMID: 19851445 PMCID: PMC2758598 DOI: 10.1371/journal.pgen.1000696] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2009] [Accepted: 09/23/2009] [Indexed: 11/24/2022] Open
Abstract
A substantial genetic contribution to systemic lupus erythematosus (SLE) risk is conferred by major histocompatibility complex (MHC) gene(s) on chromosome 6p21. Previous studies in SLE have lacked statistical power and genetic resolution to fully define MHC influences. We characterized 1,610 Caucasian SLE cases and 1,470 parents for 1,974 MHC SNPs, the highly polymorphic HLA-DRB1 locus, and a panel of ancestry informative markers. Single-marker analyses revealed strong signals for SNPs within several MHC regions, as well as with HLA-DRB1 (global p = 9.99×10−16). The most strongly associated DRB1 alleles were: *0301 (odds ratio, OR = 2.21, p = 2.53×10−12), *1401 (OR = 0.50, p = 0.0002), and *1501 (OR = 1.39, p = 0.0032). The MHC region SNP demonstrating the strongest evidence of association with SLE was rs3117103, with OR = 2.44 and p = 2.80×10−13. Conditional haplotype and stepwise logistic regression analyses identified strong evidence for association between SLE and the extended class I, class I, class III, class II, and the extended class II MHC regions. Sequential removal of SLE–associated DRB1 haplotypes revealed independent effects due to variation within OR2H2 (extended class I, rs362521, p = 0.006), CREBL1 (class III, rs8283, p = 0.01), and DQB2 (class II, rs7769979, p = 0.003, and rs10947345, p = 0.0004). Further, conditional haplotype analyses demonstrated that variation within MICB (class I, rs3828903, p = 0.006) also contributes to SLE risk independent of HLA-DRB1*0301. Our results for the first time delineate with high resolution several MHC regions with independent contributions to SLE risk. We provide a list of candidate variants based on biologic and functional considerations that may be causally related to SLE risk and warrant further investigation. Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by autoantibody production and involvement of multiple organ systems. Although the cause of SLE remains unknown, several lines of evidence underscore the importance of genetic factors. As is true for most autoimmune diseases, a substantial genetic contribution to disease risk is conferred by major histocompatibility complex (MHC) gene(s) on chromosome 6. This region of the genome contains a large number of genes that participate in the immune response. However, the full contribution of this genomic region to SLE risk has not yet been defined. In the current study we characterize a large number of SLE patients and family members for approximately 2,000 MHC region variants to identify the specific genes that influence disease risk. Our results, for the first time, implicate four different MHC regions in SLE risk. We provide a list of candidate variants based on biologic and functional considerations that may be causally related to SLE risk and warrant further investigation.
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Current strategies for monitoring men with localised prostate cancer lack a strong evidence base: observational longitudinal study. Br J Cancer 2009; 101:390-4. [PMID: 19603015 PMCID: PMC2720224 DOI: 10.1038/sj.bjc.6605181] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Background: The UK National Institute for Health and Clinical Excellence (NICE) guidance recommends conservative management of men with ‘low-risk’ localised prostate cancer, monitoring the disease using prostate-specific antigen (PSA) kinetics and re-biopsy. However, there is little evidence of the changes in PSA level that should alert to the need for clinical re-assessment. Methods: This study compares the alerts resulting from PSA kinetics and a novel longitudinal reference range approach, which incorporates age-related changes, during the monitoring of 408 men with localised prostate cancer. Men were monitored by regular PSA tests over a mean of 2.9 years, recording when a man's PSA doubling time fell below 2 years, PSA velocity exceeded 2 ng ml–1 per year, or when his upper 10% reference range was exceeded. Results: Prostate-specific antigen doubling time and PSA velocity alerted a high proportion of men initially but became unresponsive to changes with successive tests. Calculating doubling time using recent PSA measurements reduced the decline in response. The reference range method maintained responsiveness to changes in PSA level throughout the monitoring. Conclusion: The increasing unresponsiveness of PSA kinetics is a consequence of the underlying regression model. Novel methods are needed for evaluation in cohorts currently being managed by monitoring. Meanwhile, the NICE guidance should be cautious.
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Low risk research using routinely collected identifiable health information without informed consent: encounters with the Patient Information Advisory Group. JOURNAL OF MEDICAL ETHICS 2008; 34:37-40. [PMID: 18156520 PMCID: PMC2762744 DOI: 10.1136/jme.2006.019661] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Current UK legislation is impacting upon the feasibility and cost-effectiveness of medical record-based research aimed at benefiting the NHS and the public heath. Whereas previous commentators have focused on the Data Protection Act 1998, the Health and Social Care Act 2001 is the key legislation for public health researchers wishing to access medical records without written consent. The Act requires researchers to apply to the Patient Information Advisory Group (PIAG) for permission to access medical records without written permission. We present a case study of the work required to obtain the necessary permissions from PIAG in order to conduct a large scale public health research project. In our experience it took eight months to receive permission to access basic identifying information on individuals registered at general practices, and a decision on whether we could access clinical information in medical records without consent took 18 months. Such delays pose near insurmountable difficulties to grant funded research, and in our case 560,000pound of public and charitable money was spent on research staff while a large part of their work was prohibited until the third year of a three year grant. We conclude by arguing that many of the current problems could be avoided by returning PIAG's responsibilities to research ethics committees, and by allowing "opt-out" consent for many public health research projects.
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Linkage disequilibrium with predisposing DR3 haplotypes accounts for apparent effects of tumor necrosis factor and lymphotoxin-alpha polymorphisms on type 1 diabetes susceptibility. Hum Immunol 2006; 67:999-1004. [PMID: 17174749 PMCID: PMC2481238 DOI: 10.1016/j.humimm.2006.10.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2006] [Revised: 09/19/2006] [Accepted: 10/02/2006] [Indexed: 11/20/2022]
Abstract
Tumor necrosis factor (TNF) and lymphotoxin alpha (LT-alpha) are immunomodulators that have been hypothesized to contribute to susceptibility to type 1 diabetes (T1D). Several polymorphisms in the TNF and LT-alpha loci have been extensively studied for T1D association, with conflicting reports. In this study, we examined two TNF variants and one LT-alpha variant for T1D association in 283 Caucasian, multiplex T1D families for which complete human leukocyte antigen (HLA) genotyping data are available. Initially, association with T1D was seen for LT-alpha A1069G (intron A, p=0.011, rs909253) and TNF G(-308)A (p<1x10(-5), rs1800629), but no association was observed for TNF G(-238)A (rs361525). After adjusting the data for linkage disequilibrium (LD) with DRB1-DQB1 haplotypes, however, only one polymorphism, TNF G(-238)A showed significant association with T1D (p<0.006). When HLA-DR3 haplotypes were examined, the A allele of TNF G(-238)A was significantly overtransmitted to affected offspring (p<0.009). Including HLA-B data in the analysis revealed that TNF (-238)A is present exclusively on DR3 haplotypes that also carry HLA-B18. Transmission proportion of B18-DR3 haplotypes did not differ between those with TNF (-238)A and those with TNF (-238)G. Thus, variation at TNF does not affect the T1D risk for B18-DR3 haplotypes, and the apparent association of TNF(-238)A with T1D may simply reflect its presence on a high-risk haplotype.
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Relationship between the birth cohort pattern of Helicobacter pylori infection and the epidemiology of duodenal ulcer. QJM 2002; 95:519-25. [PMID: 12145391 DOI: 10.1093/qjmed/95.8.519] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Helicobacter-pylori-related duodenal ulcer (DU) is an important cause of dyspepsia. AIM To determine the relationship between the pattern of H. pylori infection and the epidemiology of duodenal ulcer in a single population. DESIGN Prospective two-part study of (i) patients with DU referred for endoscopy because of dyspepsia, and (ii) the incidence of H. pylori infection in the general population of the same area. METHODS Details of 533 DU patients were recorded, and related to the pattern of H. pylori infection among 10 537 adults in the same community, determined by the (13)C-urea breath test. RESULTS In patients with DU, birth year was more important than age in determining the rate of presentation for endoscopy (the 'birth cohort' effect). H. pylori infection showed a similar birth cohort effect, and the prevalence decreased steadily in those born in successive years, from 28.8% in the 1930s to 3.5% in the 1970s. The proportion of dyspeptic patients who had duodenal ulcers also fell progressively, from 22.2% in 1979 to 5.7% in 1998. H. pylori prevalence and duodenal ulcer incidence were closely correlated at all ages. DISCUSSION Duodenal ulcer prevalence (as judged by the rate of referral of duodenal ulcer patients for endoscopy) is determined principally by the distribution of H. pylori infection in the local population. The birth cohort effect seen in adult duodenal ulcer patients reflects the acquisition of H. pylori in childhood. In Bristol, H. pylori prevalence and duodenal ulcer incidence are both declining to very low levels.
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Cognitive Load and the Equality Heuristic: A Two-Stage Model of Resource Overconsumption in Small Groups. ORGANIZATIONAL BEHAVIOR AND HUMAN DECISION PROCESSES 2000; 83:185-212. [PMID: 11056068 DOI: 10.1006/obhd.2000.2915] [Citation(s) in RCA: 145] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Two studies were conducted to test a two-stage model of the psychological mechanisms underlying the overconsumption of scarce resources in small groups. The model proposes that members of groups sharing resources first anchor their consumption choices on an "equal-division" heuristic and then, given sufficient cognitive capacity, adjust their choices in a self-serving direction. The results from both studies support the model. The first study found that when faced with a common resource pool almost all group members expressed thoughts regarding equality; however, individuals with sufficient cognitive capacity requested more from the pool and expressed more task-relevant thoughts than individuals lacking the necessary cognitive resources. The second study provided additional support for the two-stage model by demonstrating that group members' cognitions occur in the order predicted by the model and by demonstrating that an individual difference, social value orientation, affects thought processes only when individuals are not experiencing high cognitive loads. Implications are discussed. Copyright 2000 Academic Press.
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Correlation between surface water contamination with amoeba and the onset of symptoms and diagnosis of amoeba-like keratitis. Br J Ophthalmol 1998; 82:1143-6. [PMID: 9924301 PMCID: PMC1722385 DOI: 10.1136/bjo.82.10.1143] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AIM A seasonal variation was noted in the incidence of amoeba-like keratitis in Iowa. The level of contamination of amoeba in surface water has been found previously to vary on a monthly basis for Tulsa, Oklahoma, a region with a similar climate. It was hypothesised that this seasonal variation in amoeba-like keratitis correlated with the concentration of amoeba in surface water. METHODS The monthly variation in the onset of symptoms was determined and date of diagnosis in 137 cases of amoeba-like keratitis, in Iowa, from January 1993 to the end of December 1996. RESULTS Over a 4 year period a significant variation was found, on a monthly basis, in the onset of symptoms as reported by the patient. There were two peak periods per year when the onset of symptoms was most frequent: June and November. This corresponded closely with the concentration of amoeba in the ground water reported for a similar region in the mid-west (Tulsa, Oklahoma). A yearly increase was found in the number of cases diagnosed from January 1993 to the end of December 1996. CONCLUSIONS This study supports the hypothesis that the concentration of amoeba in surface water may influence the rate of an amoeba-like keratitis infection.
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Abstract
PURPOSE The onset of dry eye is very common during menopause and may result from the loss of hormonal support. The purpose of this study was to assess the effect that changes in sex hormone and prolactin levels have on tear function in premenopausal and menopausal woman. METHODS Women between the ages of 30 and 60 were solicited to participate in a study concerning menopause and tear function. One-hundred and ten women were given tear function tests (osmolarity, tear volume, tear flow, Schirmer's test) and serum levels were measured for total testosterone, estradiol, prolactin, and follicle stimulating hormone. RESULTS For all women on hormone replacement therapy, we found a strong negative correlation between serum prolactin level and tear function. For women in menopause, total testosterone correlated positively with tear function, whereas for premenopausal women there was a negative correlation between total testosterone and tear function. Serum estradiol levels correlated positively with tear function for women 30-39 years of age, whereas for menopausal women the correlation was negative. CONCLUSIONS This is the first demonstration in humans that tear production is correlated with serum prolactin and sex hormone levels prior to and during the menopause.
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Meibomian gland lipids, evaporation, and tear film stability. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1998; 438:349-60. [PMID: 9634908 DOI: 10.1007/978-1-4615-5359-5_50] [Citation(s) in RCA: 143] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Assessment of the tear film with tandem scanning confocal microscopy. Cornea 1997; 16:162-8. [PMID: 9071529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
PURPOSE To evaluate the confocal microscopic appearance of the tear film by correlating the interference pattern created by the lipid surface with physiologic measurements of tear function and with clinic diagnosis. METHODS A series of 53 patients was examined with a battery of tests to evaluate the tear film and with confocal microscopy to evaluate the interference pattern created by the lipid surface of the tear film. Assessment of the tear-film appearance involved five nonparametric scales: degree of debris in the tear film, variability of the interference pattern over time, linearity of the interference pattern, number of dry spots seen, and relative thickness of the lipid layer. For 10 other subjects, the confocal appearance of the tear film and evaporation from the ocular surface was tested for before and after meibomian gland expression. RESULTS The confocal appearance correlated with multiple physiologic variables and clinical diagnosis. Patients with seborrheic meiboman gland dysfunction had a thicker lipid layer, greater variability, and more debris than did patients with obstructive meibomiam gland dysfunction. After meibomian gland expression, lipid thickness and linearity increased, whereas pattern variability and evaporation decreased significantly. The mean reduction in evaporation was 48%. CONCLUSIONS Confocal microscopy can be used to examine the tear film, and its appearance correlates significantly with physiologic variables in normal-individuals and in disease states. The confocal appearance of the lipid interference patterns and evaporation from the ocular surface are altered after lipid expression from meibomian glands.
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Abstract
A tandem scanning confocal microscope (TSCM) is currently being used to obtain high-resolution images of the human cornea in vivo. Advantages of confocal microscopy for in vivo imaging include optical sectioning and increased contrast through removal of scattered light. We have adapted to TSCM to view the retina in vivo by constructing an applanating lens and fitting the microscope with an imaging-intensifying camera of increased sensitivity. The microscope uses a spinning disc with 40,000 holes, each of 30 microns diameter, and a 100 W mercury arc lamp light source with a 455 nm long pass filter. The applanating lens is composed of three elements, two of which are movable for focusing. Images of a rabbit retina were obtained in vivo revealing the nerve fiber layer and blood vessels around the optic disc. The power density at the retina was calculated to be 3 mW/cm2, which is well below the power levels of a direct or indirect ophthalmoscope. Magnification of the retinal image was approximately 60 x and a 1 mm wide area of retina was in view. This prototype TSCM system demonstrates that images of a retina in vivo are obtainable with confocal microscopy and that the sharpness is comparable to standard fundus camera photography. Further modifications to improve the light level and alterations in the design of the objective should improve the quality of the images obtained and achieve the enhanced resolution of which, in theory, the confocal microscope is capable.
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Abstract
We examined a group of normal subjects to evaluate the tear film function by measuring reflex tear capacity using the Schirmer test without anesthetic, steady state tear flow using fluorophotometry, meibomian gland function based on gland drop-out, expressible lipid volume and viscosity, tear loss from evaporation, and tear osmolarity. We found the average tear flow to be 0.19 +/- 0.19 microliters/min, lower than previously measured. The average tear volume was also correspondingly less, 2.74 +/- 2.0 microliters. We found there was a decline associated with advancing age for all parameters except the decay constant and lipid volume. The highest correlations with aging were tear volume (-0.64), Schirmer test (-0.63), and tear osmolarity (0.59). Our results indicate that there is a decline in tear film function throughout life and that tear flow is considerably less than previously estimated.
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Abstract
Blepharitis patients have a number of disturbances in their tear film associated with meibomian gland dysfunction that affect evaporation and tear osmolarity. We tested a series of 156 consecutive patients, with a presumed diagnosis of blepharitis, dry eye, or allergic disease, and a series of 72 normals. We compared their tear film characteristics using tear osmolarity, tear volume, tear production (fluorophotometric and Schirmer test), tear turnover (decay constant), tear evaporation, and meibomian gland function evaluated by gland drop-out, expressed lipid viscosity, and volume. Of the 156 patients tested, we found 37 had dry eye, 10 had only allergic disease, 73 had meibomian gland dysfunction and dry eye, and 36 had only meibomian gland dysfunction. We created a model of the relative influence some of these factors had on each other using their correlation coefficients. The highest correlations for osmolarity were Schirmer test (-0.44), lipid volume low (-0.44), lipid viscosity high (0.39), gland drop-out (0.39), and tear evaporation (0.36). With regression analysis we accounted for 47% of the total variation in osmolarity, but only 17% of the variation in tear evaporation. We also present our classification system for blepharitis and dry eye patients based on our measurable physiologic parameters.
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Cysteine analogs of recombinant barley ribosome inactivating protein form antibody conjugates with enhanced stability and potency in vitro. Bioconjug Chem 1994; 5:126-32. [PMID: 8031875 DOI: 10.1021/bc00026a004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Antibody immunoconjugates were made with native and recombinant forms of the type-I ribosome inactivating protein from barley (BRIP) and with three recombinant BRIP (rBRIP) analogs engineered to contain a unique cysteine residue near the C terminus (at amino acid 256, 270, or 277). rBRIP and all three cysteine analogs (rBRIPc256, rBRIPc270, and rBRIPc277) were produced in E. coli, with yields of soluble protein as high as 1 g/L, and were as active as native BRIP in inhibiting protein synthesis in vitro. Interestingly, the position of the engineered cysteine influenced not only the efficiency of conjugation to antibody but also the efficacy and disulfide bond stability of the immunoconjugates. Anti-CD5 antibody conjugates prepared with native and rBRIP were relatively inactive against antigen-positive target cells, while the conjugate made with rBRIPc277 was 5-fold more cytotoxic. Anti-CD7 antibody conjugates made with rBRIPc277 or rBRIPc270 also exhibited improved potency and stability compared to the conjugate with native BRIP. These results indicate that engineering a cysteine residue into selected positions near the C-terminus of a type-IRIP such as BRIP can improve immunoconjugate yield, disulfide bond stability, and potency.
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A workable framework for health reform. Health Aff (Millwood) 1994; 13:248-50. [PMID: 8188141 DOI: 10.1377/hlthaff.13.1.248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Resistance of cowpea [Vigna unguiculata (L.) Walp.] to Striga gesnerioides (Willd.) Vatke, a parasitic angiosperm. THE NEW PHYTOLOGIST 1993; 125:405-412. [PMID: 33874504 DOI: 10.1111/j.1469-8137.1993.tb03893.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
An in vitro growth system was used to investigate the expression of resistance of cowpea [Vigna unguiculata (L.) Walp.] varieties B301 and 58-57 to the angiosperm parasite Striga gesnerioides (Willd.) Vatke. Variety Blackeye was included in experiments as a susceptible control. Seeds of S. gesnerioides germinated on the roots of all varieties. Two different mechanisms of resistance were expressed in B301 and 58-57 after penetration of host roots by parasite radicles. The first mechanism was expressed in both varieties; host tissue around invading Striga radicles became necrotic in association with the early death of the parasite and lack of tubercle formation. On variety 58-57, the necrosis response was expressed only when the roots were inoculated with Striga from Burkina Faso but Striga from Mali successfully parasitized the roots of variety 58-57. The second mechanism was observed only on variety B301. Striga radicles infected cowpea roots, tubercles were formed but remained at 1-2 mm in diameter with very limited stem growth. No further development of the parasite occurred in vitro or when infected cowpeas were grown in soil or vermiculite. Similarities between the expression of resistance of cowpea to Striga and ot plants to plant pathogenic fungi are discussed.
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Returning Gospel values to nursing education. Catholic educators and institutions must make explicit the values on which their practices are based. HEALTH PROGRESS (SAINT LOUIS, MO.) 1993; 74:30-5. [PMID: 10126221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Although Catholic nursing education in the United States has traditionally instilled Gospel values in students, pressures from a secular culture are making it increasingly difficult to sustain this heritage. As the twenty-first century approaches, Catholic educators and healthcare administrators need to ask themselves whether Christian values still serve as the explicit basis of nursing service and education at their institutions. They must also ask what distinguishes graduates of Catholic nursing programs from those of other programs. The percentage of schools that are Catholic has remained roughly the same during the past 30 years, but in many cases these schools no longer instill Christian values. Although most programs offer courses in ethics, philosophy, and religion, few provide the value-laden experiences of the past. In fact, many instructors avoid addressing questions of values or ethics because they believe doing so would be a form of indoctrination. Catholic nursing education, like Catholic higher education in general, is becoming increasingly secular. To return Christian values to nursing practice and education, leaders need first to instill a sense of self-worth in nursing staff by letting them know they are valued and their efforts are appreciated. Leaders also need to emphasize the good their institutions do for their communities and make explicit the values on which their practices are based.
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Potent anti-CD5 ricin A chain immunoconjugates from bacterially produced Fab' and F(ab')2. Proc Natl Acad Sci U S A 1993; 90:457-61. [PMID: 7678457 PMCID: PMC45682 DOI: 10.1073/pnas.90.2.457] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
We have used genetic engineering to obtain secretion of anti-human CD5 antibody fragments from Escherichia coli for conjugation to the 30-kDa form of ricin A chain (RTA30). This was accomplished by introducing stop codons at two positions in the hinge region of the human IgG1 gene so that coexpression of the truncated heavy-chain genes (Fd') with a light chain would result in Fab' and/or F(ab')2 proteins containing either one or two interheavy-chain cysteines. An Fd' gene encoding both interheavy-chain cysteines yielded a mixture of F(ab')2 and Fab', which could be separated by size-exclusion chromatography. An Fd' gene encoding only one interheavy-chain cysteine yielded primarily Fab'. Purified F(ab')2 protein was equivalent to unlabeled chimeric IgG in competing for binding of IgG with CD5 antigen, while the molar concentration of the monovalent Fab' required for 50% binding inhibition was 4- to 5-fold higher than IgG. An immunoconjugate was prepared with Fab' by direct coupling to the unique free cysteine on RTA30. The bivalent F(ab')2 was conjugated to RTA30 after derivatization with the crosslinking agent 5-methyl-2-iminothiolane. These immunoconjugates efficiently killed a CD5+ T-cell line and human peripheral blood T cells.
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