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1.
CRISPR J ; 7(1): 53-67, 2024 02.
Article in English | MEDLINE | ID: mdl-38353623

ABSTRACT

We developed an efficient CRISPR prime editing protocol and generated isogenic-induced pluripotent stem cell (iPSC) lines carrying heterozygous or homozygous alleles for putatively causal single nucleotide variants at six type 2 diabetes loci (ABCC8, MTNR1B, TCF7L2, HNF4A, CAMK1D, and GCK). Our two-step sequence-based approach to first identify transfected cell pools with the highest fraction of edited cells significantly reduced the downstream efforts to isolate single clones of edited cells. We found that prime editing can make targeted genetic changes in iPSC and optimization of system components and guide RNA designs that were critical to achieve acceptable efficiency. Systems utilizing PEmax, epegRNA modifications, and MLH1dn provided significant benefit, producing editing efficiencies of 36-73%. Editing success and pegRNA design optimization required for each variant differed depending on the sequence at the target site. With attention to design, prime editing is a promising approach to generate isogenic iPSC lines, enabling the study of specific genetic changes in a common genetic background.


Subject(s)
Diabetes Mellitus, Type 2 , Induced Pluripotent Stem Cells , Humans , Clustered Regularly Interspaced Short Palindromic Repeats/genetics , CRISPR-Cas Systems/genetics , Gene Editing , RNA, Guide, CRISPR-Cas Systems
2.
Am J Hum Genet ; 110(2): 284-299, 2023 02 02.
Article in English | MEDLINE | ID: mdl-36693378

ABSTRACT

Insulin secretion is critical for glucose homeostasis, and increased levels of the precursor proinsulin relative to insulin indicate pancreatic islet beta-cell stress and insufficient insulin secretory capacity in the setting of insulin resistance. We conducted meta-analyses of genome-wide association results for fasting proinsulin from 16 European-ancestry studies in 45,861 individuals. We found 36 independent signals at 30 loci (p value < 5 × 10-8), which validated 12 previously reported loci for proinsulin and ten additional loci previously identified for another glycemic trait. Half of the alleles associated with higher proinsulin showed higher rather than lower effects on glucose levels, corresponding to different mechanisms. Proinsulin loci included genes that affect prohormone convertases, beta-cell dysfunction, vesicle trafficking, beta-cell transcriptional regulation, and lysosomes/autophagy processes. We colocalized 11 proinsulin signals with islet expression quantitative trait locus (eQTL) data, suggesting candidate genes, including ARSG, WIPI1, SLC7A14, and SIX3. The NKX6-3/ANK1 proinsulin signal colocalized with a T2D signal and an adipose ANK1 eQTL signal but not the islet NKX6-3 eQTL. Signals were enriched for islet enhancers, and we showed a plausible islet regulatory mechanism for the lead signal in the MADD locus. These results show how detailed genetic studies of an intermediate phenotype can elucidate mechanisms that may predispose one to disease.


Subject(s)
Diabetes Mellitus, Type 2 , Proinsulin , Humans , Proinsulin/genetics , Proinsulin/metabolism , Diabetes Mellitus, Type 2/genetics , Diabetes Mellitus, Type 2/metabolism , Genome-Wide Association Study/methods , Insulin/genetics , Insulin/metabolism , Glucose , Transcription Factors/genetics , Homeodomain Proteins/genetics
3.
Am J Hum Genet ; 109(1): 66-80, 2022 01 06.
Article in English | MEDLINE | ID: mdl-34995504

ABSTRACT

Alternate splicing events can create isoforms that alter gene function, and genetic variants associated with alternate gene isoforms may reveal molecular mechanisms of disease. We used subcutaneous adipose tissue of 426 Finnish men from the METSIM study and identified splice junction quantitative trait loci (sQTLs) for 6,077 splice junctions (FDR < 1%). In the same individuals, we detected expression QTLs (eQTLs) for 59,443 exons and 15,397 genes (FDR < 1%). We identified 595 genes with an sQTL and exon eQTL but no gene eQTL, which could indicate potential isoform differences. Of the significant sQTL signals, 2,114 (39.8%) included at least one proxy variant (linkage disequilibrium r2 > 0.8) located within an intron spanned by the splice junction. We identified 203 sQTLs that colocalized with 141 genome-wide association study (GWAS) signals for cardiometabolic traits, including 25 signals for lipid traits, 24 signals for body mass index (BMI), and 12 signals for waist-hip ratio adjusted for BMI. Among all 141 GWAS signals colocalized with an sQTL, we detected 26 that also colocalized with an exon eQTL for an exon skipped by the sQTL splice junction. At a GWAS signal for high-density lipoprotein cholesterol colocalized with an NR1H3 sQTL splice junction, we show that the alternative splice product encodes an NR1H3 transcription factor that lacks a DNA binding domain and fails to activate transcription. Together, these results detect splicing events and candidate mechanisms that may contribute to gene function at GWAS loci.


Subject(s)
Alternative Splicing , Cardiometabolic Risk Factors , Gene Expression Regulation , Quantitative Trait Loci , Quantitative Trait, Heritable , Subcutaneous Fat/metabolism , Binding Sites , Cardiovascular Diseases/etiology , Cardiovascular Diseases/metabolism , Computational Biology/methods , Exons , Finland , Genes, Reporter , Genetic Association Studies , Genetic Predisposition to Disease , Genetics, Population , Genome-Wide Association Study/methods , High-Throughput Nucleotide Sequencing , Humans , Liver X Receptors/genetics , Male , Metabolic Syndrome/etiology , Metabolic Syndrome/metabolism , Molecular Sequence Annotation , Phenotype , Protein Isoforms/genetics , RNA Splice Sites , RNA-Binding Proteins
4.
Circulation ; 142(5): 466-482, 2020 08 04.
Article in English | MEDLINE | ID: mdl-32403949

ABSTRACT

BACKGROUND: The human heart requires a complex ensemble of specialized cell types to perform its essential function. A greater knowledge of the intricate cellular milieu of the heart is critical to increase our understanding of cardiac homeostasis and pathology. As recent advances in low-input RNA sequencing have allowed definitions of cellular transcriptomes at single-cell resolution at scale, we have applied these approaches to assess the cellular and transcriptional diversity of the nonfailing human heart. METHODS: Microfluidic encapsulation and barcoding was used to perform single nuclear RNA sequencing with samples from 7 human donors, selected for their absence of overt cardiac disease. Individual nuclear transcriptomes were then clustered based on transcriptional profiles of highly variable genes. These clusters were used as the basis for between-chamber and between-sex differential gene expression analyses and intersection with genetic and pharmacologic data. RESULTS: We sequenced the transcriptomes of 287 269 single cardiac nuclei, revealing 9 major cell types and 20 subclusters of cell types within the human heart. Cellular subclasses include 2 distinct groups of resident macrophages, 4 endothelial subtypes, and 2 fibroblast subsets. Comparisons of cellular transcriptomes by cardiac chamber or sex reveal diversity not only in cardiomyocyte transcriptional programs but also in subtypes involved in extracellular matrix remodeling and vascularization. Using genetic association data, we identified strong enrichment for the role of cell subtypes in cardiac traits and diseases. Intersection of our data set with genes on cardiac clinical testing panels and the druggable genome reveals striking patterns of cellular specificity. CONCLUSIONS: Using large-scale single nuclei RNA sequencing, we defined the transcriptional and cellular diversity in the normal human heart. Our identification of discrete cell subtypes and differentially expressed genes within the heart will ultimately facilitate the development of new therapeutics for cardiovascular diseases.


Subject(s)
Myocardium/cytology , Transcription, Genetic , Adipocytes/metabolism , Adult , Aged , Cardiovascular Agents/pharmacology , Cardiovascular Agents/therapeutic use , Endothelial Cells/classification , Endothelial Cells/metabolism , Fibroblasts/classification , Fibroblasts/metabolism , Gene Ontology , Heart/innervation , Heart Atria/cytology , Heart Diseases/drug therapy , Heart Ventricles/cytology , Homeostasis , Humans , Lymphocyte Subsets/metabolism , Macrophages/classification , Macrophages/metabolism , Microfluidic Analytical Techniques , Middle Aged , Myocardium/metabolism , Myocytes, Cardiac/metabolism , Myocytes, Smooth Muscle/metabolism , Pericytes/metabolism , RNA-Seq , Sex Characteristics , Single-Cell Analysis , Transcriptome
5.
PLoS One ; 15(2): e0229224, 2020.
Article in English | MEDLINE | ID: mdl-32097441

ABSTRACT

BACKGROUND: The current UK vaccination programme for herpes zoster (HZ) excludes people aged ≥80 years. This study aimed to quantify the number of individuals ≥80 years who missed HZ vaccination and the consequent epidemiological and economic burden of HZ and post-herpetic neuralgia (PHN). METHODS: Immunocompetent individuals aged ≥80 years between 1st September 2013 and 31st December 2017 in the Clinical Practice Research Datalink were selected and linked to Hospital Episodes Statistics, where available. Rates of HZ and PHN and healthcare resource utilisation were investigated for the overall study population and by age group (80-84, 85-89, ≥90 years old) and the burden of HZ and PHN was projected to the UK population. RESULTS: 4,858 HZ episodes and 464 PHN cases were identified in 255,165 individuals over 576,421 person-years (PY). Rates of HZ and PHN were 8.43 (95% confidence interval [CI] 8.19-8.66) and 0.80 (0.73-0.87) per 1,000 PY respectively and lowest in those aged ≥90 (HZ rate 7.37/1,000 PY; PHN rate 0.56/1,000 PY). Within HZ episodes, 10.27% of GP visits, 5.82% of prescribed medications and 21.65% of hospitalisations were related to HZ/PHN. Median length of hospitalisation increased from 7.0 days for all-cause to 10.5 days for HZ/PHN related hospitalisations. Individuals ≥90 stayed in hospital a median of 3-4 days longer than younger groups. Approximately 2.23 million individuals in the UK missed HZ vaccination since 2013 (1.86 million had never been eligible and 365,000 lost eligibility for HZ vaccination), resulting in an estimated 43,149 HZ episodes. CONCLUSION: This study highlights the impact of the 80-year upper age limit policy on the health system. Our study estimates that 2.23 million individuals in the UK may have lost the opportunity to be vaccinated and that their burden of HZ and PHN remains high, especially among the very elderly.


Subject(s)
Health Services/statistics & numerical data , Herpes Zoster/economics , Herpes Zoster/epidemiology , Hospitalization/statistics & numerical data , Neuralgia, Postherpetic/economics , Neuralgia, Postherpetic/epidemiology , Aged, 80 and over , Female , Follow-Up Studies , Health Care Costs , Health Services/economics , Herpesvirus 3, Human/isolation & purification , Hospitalization/economics , Humans , Incidence , Male , Prognosis , Retrospective Studies , United Kingdom/epidemiology
6.
BMJ Open ; 9(8): e031550, 2019 08 28.
Article in English | MEDLINE | ID: mdl-31462487

ABSTRACT

OBJECTIVE: Evaluate the association between gout and risk of advanced chronic kidney disease (CKD). DESIGN: Retrospective matched cohort study. SETTING: UK Clinical Practice Research Datalink. PARTICIPANTS: The analysis included data for 68 897 patients with gout and 554 964 matched patients without gout. Patients were aged ≥18 years, registered at UK practices, had ≥12 months of clinical data and had data linked with Hospital Episode Statistics. Patients were excluded for history of advanced CKD, juvenile gout, cancer, HIV, tumour lysis syndrome, Lesch-Nyhan syndrome or familial Mediterranean fever. PRIMARY AND SECONDARY OUTCOME MEASURES: Advanced CKD was defined as first occurrence of: (1) dialysis, kidney transplant, diagnosis of end-stage kidney disease (ESKD) or stage 5 CKD (diagnostic codes in Read system or International Classification of Diseases, Tenth Revision); (2) estimated glomerular filtration rate (eGFR) <10 mL/min/1.73 m²; (3) doubling of serum creatinine from baseline and (4) death associated with CKD. RESULTS: Advanced CKD incidence was higher for patients with gout (8.54 per 1000 patient-years; 95% CI 8.26 to 8.83) versus without gout (4.08; 95% CI 4.00 to 4.16). Gout was associated with higher advanced CKD risk in both unadjusted analysis (HR, 2.00; 95% CI 1.92 to 2.07) and after adjustment (HR, 1.29; 95% CI 1.23 to 1.35). Association was strongest for ESKD (HR, 2.13; 95% CI 1.73 to 2.61) and was present for eGFR <10 mL/min/1.73 m² (HR, 1.45; 95% CI 1.30 to 1.61) and serum creatinine doubling (HR, 1.13; 95% CI 1.08 to 1.19) but not CKD-associated death (HR, 1.14; 95% CI 0.99 to 1.31). Association of gout with advanced CKD was replicated in propensity-score matched analysis (HR, 1.23; 95% CI 1.17 to 1.29) and analysis limited to patients with incident gout (HR, 1.28; 95% CI 1.22 to 1.35). CONCLUSIONS: Gout is associated with elevated risk of CKD progression. Future studies should investigate whether controlling gout is protective and reduces CKD risk.


Subject(s)
Gout/epidemiology , Kidney Failure, Chronic/epidemiology , Renal Insufficiency, Chronic/epidemiology , Aged , Creatinine/blood , Databases, Factual , Disease Progression , Female , Glomerular Filtration Rate , Humans , Incidence , Kidney Failure, Chronic/therapy , Kidney Transplantation , Male , Middle Aged , Propensity Score , Renal Dialysis , Renal Insufficiency, Chronic/therapy , Retrospective Studies , United Kingdom/epidemiology
7.
Circ Genom Precis Med ; 11(3): e001901, 2018 03.
Article in English | MEDLINE | ID: mdl-29540468

ABSTRACT

BACKGROUND: Inhibition of PKC-α (protein kinase C-α) enhances contractility and cardioprotection in animal models, but effects in humans are unknown. Genotypes at rs9912468 strongly associate with PRKCA expression in the left ventricle, enabling genetic approaches to measure effects of reduced PKC-α in human populations. METHODS AND RESULTS: We analyzed the cis expression quantitative trait locus for PRKCA marked by rs9912468 using 313 left ventricular specimens from European Ancestry patients. The forward strand minor allele (G) at rs9912468 is associated with reduced PKC-α transcript abundance (1.7-fold reduction in minor allele homozygotes, P=1×10-41). This association was cardiac specific in expression quantitative trait locus data sets that span 16 human tissues. Cardiac epigenomic data revealed a predicted enhancer in complete (R2=1.0) linkage disequilibrium with rs9912468 within intron 2 of PRKCA. We cloned this region and used reporter constructs to verify cardiac-specific enhancer activity in vitro in cardiac and noncardiac cells and in vivo in zebrafish. The PRKCA enhancer contains 2 common genetic variants and 4 haplotypes; the haplotype correlated with the rs9912468 PKC-α-lowering allele (G) showed lowest activity. In contrast to previous reports in animal models, the PKC-α-lowering allele is associated with adverse left ventricular remodeling (higher mass, larger diastolic dimension), reduced fractional shortening, and higher risk of dilated cardiomyopathy in human populations. CONCLUSIONS: These findings support PKC-α as a regulator of the human heart but suggest that PKC-α inhibition may adversely affect the left ventricle depending on timing and duration. Pharmacological studies in human subjects are required to discern potential benefits and harms of PKC-α inhibitors as an approach to treat heart disease.


Subject(s)
Heart Ventricles/metabolism , Protein Kinase C-alpha/genetics , Ventricular Remodeling/genetics , Adult , Aged , Alleles , Animals , Female , Genes, Reporter , Genetic Predisposition to Disease , Genotype , Haplotypes , Homozygote , Humans , Introns , Linkage Disequilibrium , Male , Middle Aged , Protein Kinase C-alpha/metabolism , Quantitative Trait Loci , Zebrafish
8.
Circ Cardiovasc Genet ; 10(6)2017 Dec.
Article in English | MEDLINE | ID: mdl-29212899

ABSTRACT

BACKGROUND: Restrictive cardiomyopathy (RCM) is a rare cardiomyopathy characterized by impaired diastolic ventricular function resulting in a poor clinical prognosis. Rarely, heritable forms of RCM have been reported, and mutations underlying RCM have been identified in genes that govern the contractile function of the cardiomyocytes. METHODS AND RESULTS: We evaluated 8 family members across 4 generations by history, physical examination, electrocardiography, and echocardiography. Affected individuals presented with a pleitropic syndrome of progressive RCM, atrioventricular septal defects, and a high prevalence of atrial fibrillation. Exome sequencing of 5 affected members identified a single novel missense variant in a highly conserved residue of FLNC (filamin C; p.V2297M). FLNC encodes filamin C-a protein that acts as both a scaffold for the assembly and organization of the central contractile unit of striated muscle and also as a mechanosensitive signaling molecule during cell migration and shear stress. Immunohistochemical analysis of FLNC localization in cardiac tissue from an affected family member revealed a diminished localization at the z disk, whereas traditional localization at the intercalated disk was preserved. Stem cell-derived cardiomyocytes mutated to carry the effect allele had diminished contractile activity when compared with controls. CONCLUSION: We have identified a novel variant in FLNC as pathogenic variant for familial RCM-a finding that further expands on the genetic basis of this rare and morbid cardiomyopathy.


Subject(s)
Cardiomyopathy, Restrictive/genetics , Filamins/genetics , Genetic Predisposition to Disease , Mutation/genetics , Adult , Aged , Amino Acid Sequence , Base Sequence , Cardiomyopathy, Restrictive/pathology , Family , Female , Filamins/chemistry , Humans , Male , Middle Aged , Phenotype
9.
Circ Cardiovasc Genet ; 10(5)2017 Oct.
Article in English | MEDLINE | ID: mdl-28974514

ABSTRACT

BACKGROUND: Atrial fibrillation (AF) affects over 33 million individuals worldwide. Genome-wide association studies have identified at least 30 AF loci, but the mechanisms through which individual variants lead to altered disease risk have remained unclear for the majority of these loci. At the 1q24 locus, we hypothesized that the transcription factor PRRX1 could be a strong candidate gene as it is expressed in the pulmonary veins, a source of AF in many individuals. We sought to identify the molecular mechanism, whereby variation at 1q24 may lead to AF susceptibility. METHODS AND RESULTS: We sequenced a ≈158 kb region encompassing PRRX1 in 962 individuals with and without AF. We identified a broad region of association with AF at the 1q24 locus. Using in silico prediction and functional validation, we identified an enhancer that interacts with the promoter of PRRX1 in cells of cardiac lineage. Within this enhancer, we identified a single-nucleotide polymorphism, rs577676, which alters enhancer activity in a mouse atrial cell line and in embryonic zebrafish and differentially regulates PRRX1 expression in human left atria. We found that suppression of PRRX1 in human embryonic stem cell-derived cardiomyocytes and embryonic zebrafish resulted in shortening of the atrial action potential duration, a hallmark of AF. CONCLUSIONS: We have identified a functional genetic variant that alters PRRX1 expression, ultimately resulting in electrophysiological alterations in atrial myocytes that may promote AF.


Subject(s)
Action Potentials/genetics , Atrial Fibrillation , Homeodomain Proteins , Human Embryonic Stem Cells/metabolism , Myocytes, Cardiac/metabolism , Polymorphism, Single Nucleotide , Animals , Animals, Genetically Modified , Atrial Fibrillation/genetics , Atrial Fibrillation/metabolism , Atrial Fibrillation/physiopathology , Cell Line , Homeodomain Proteins/biosynthesis , Homeodomain Proteins/genetics , Human Embryonic Stem Cells/pathology , Humans , Mice , Myocytes, Cardiac/pathology , Zebrafish
10.
Heart Rhythm ; 14(2): 284-291, 2017 02.
Article in English | MEDLINE | ID: mdl-27756709

ABSTRACT

BACKGROUND: The genetic basis of atrial fibrillation (AF) and congenital heart disease remains incompletely understood. OBJECTIVE: We sought to determine the causative mutation in a family with AF, atrial septal defects, and ventricular septal defects. METHODS: We evaluated a pedigree with 16 family members, 1 with an atrial septal defect, 1 with a ventricular septal defect, and 3 with AF; we performed whole exome sequencing in 3 affected family members. Given that early-onset AF was prominent in the family, we then screened individuals with early-onset AF, defined as an age of onset <66 years, for mutations in GATA6. Variants were functionally characterized using reporter assays in a mammalian cell line. RESULTS: Exome sequencing in 3 affected individuals identified a conserved mutation, R585L, in the transcription factor gene GATA6. In the Massachusetts General Hospital Atrial Fibrillation (MGH AF) Study, the mean age of AF onset was 47.1 ± 10.9 years; 79% of the participants were men; and there was no evidence of structural heart disease. We identified 3 GATA6 variants (P91S, A177T, and A543G). Using wild-type and mutant GATA6 constructs driving atrial natriuretic peptide promoter reporter, we found that 3 of the 4 variants had a marked upregulation of luciferase activity (R585L: 4.1-fold, P < .0001; P91S: 2.5-fold, P = .0002; A177T; 1.7-fold, P = .03). In addition, when co-overexpressed with GATA4 and MEF2C, GATA6 variants exhibited upregulation of the alpha myosin heavy chain and atrial natriuretic peptide reporter activity. CONCLUSION: Overall, we found gain-of-function mutations in GATA6 in both a family with early-onset AF and atrioventricular septal defects as well as in a family with sporadic, early-onset AF.


Subject(s)
Atrial Fibrillation , Exome Sequencing , GATA6 Transcription Factor/genetics , Heart Septal Defects, Atrial , Heart Septal Defects, Ventricular , Adult , Age of Onset , Atrial Fibrillation/diagnosis , Atrial Fibrillation/epidemiology , Atrial Fibrillation/genetics , Female , Heart Septal Defects, Atrial/diagnosis , Heart Septal Defects, Atrial/epidemiology , Heart Septal Defects, Atrial/genetics , Heart Septal Defects, Ventricular/diagnosis , Heart Septal Defects, Ventricular/epidemiology , Heart Septal Defects, Ventricular/genetics , Humans , Male , Massachusetts/epidemiology , Middle Aged , Mutation , Pedigree , Exome Sequencing/methods
11.
Breast Cancer (Auckl) ; 10: 157-167, 2016.
Article in English | MEDLINE | ID: mdl-27812285

ABSTRACT

Previous data obtained in our laboratory suggested that there may be constitutive signaling through the myeloid differentiation primary response gene 88 (Myd88)-dependent signaling cascade in murine mammary carcinoma. Here, we extended these findings by showing that, in the absence of an added Toll-like receptor (TLR) agonist, the myddosome complex was preformed in 4T1 tumor cells, and that Myd88 influenced cytoplasmic extracellular signal-regulated kinase (Erk)1/Erk2 levels, nuclear levels of nuclear factor-kappaB (NFκB) and signal transducer and activator of transcription 5 (STAT5), tumor-derived chemokine (C-C motif) ligand 2 (CCL2) expression, and in vitro and in vivo tumor growth. In addition, RNA-sequencing revealed that Myd88-dependent signaling enhanced the expression of genes that could contribute to breast cancer progression and genes previously associated with poor outcome for patients with breast cancer, in addition to suppressing the expression of genes capable of inhibiting breast cancer progression. Yet, Myd88-dependent signaling in tumor cells also suppressed expression of genes that could contribute to tumor progression. Collectively, these data revealed a multifaceted role for Myd88-dependent signaling in murine mammary carcinoma.

12.
Lancet HIV ; 3(9): e431-e440, 2016 09.
Article in English | MEDLINE | ID: mdl-27562744

ABSTRACT

BACKGROUND: HIV incidence in men who have sex with men (MSM) in the UK has remained unchanged over the past decade despite increases in HIV testing and antiretroviral therapy (ART) coverage. In this study, we examine trends in sexual behaviours and HIV testing in MSM and explore the risk of transmitting and acquiring HIV. METHODS: In this serial cross-sectional study, we obtained data from ten cross-sectional surveys done between 2000 and 2013, consisting of anonymous self-administered questionnaires and oral HIV antibody testing in MSM recruited in gay social venues in London, UK. Data were collected between October and January for all survey years up to 2008 and between February and August thereafter. All men older than 16 years were eligible to take part and fieldworkers attempted to approach all MSM in each venue and recorded refusal rates. Data were collected on demographic and sexual behavioural characteristics. We analysed trends over time using linear, logistic, and quantile regression. FINDINGS: Of 13 861 questionnaires collected between 2000 and 2013, we excluded 1985 (124 had completed the survey previously or were heterosexual reporting no anal intercourse in the past year, and 1861 did not provide samples for antibody testing). Of the 11 876 eligible MSM recruited, 1512 (13%) were HIV positive, with no significant trend in HIV positivity over time. 35% (531 of 1505) of HIV-positive MSM had undiagnosed infection, which decreased non-linearly over time from 34% (45 of 131) to 24% (25 of 106; p=0·01), while recent HIV testing (ie, in the past year) increased from 26% (263 of 997) to 60% (467 of 777; p<0·0001). The increase in recent testing in undiagnosed men (from 29% to 67%, p<0·0001) and HIV-negative men (from 26% to 62%, p<0·0001) suggests that undiagnosed infection might increasingly be recently acquired infection. The proportion of MSM reporting unprotected anal intercourse (UAI) in the past year increased from 43% (513 of 1187) to 53% (394 of 749; p<0·0001) and serosorting (exclusively) increased from 18% (207 of 1132) to 28% (177 of 6369; p<0·0001). 268 (2%) of 11 570 participants had undiagnosed HIV and reported UAI in the past year were at risk of transmitting HIV. Additionally 259 (2%) had diagnosed infection and reported UAI and non-exclusive serosorting in the past year. Although we did not collect data on antiretroviral therapy or viral load, surveillance data suggests that a small proportion of men with diagnosed infection will have detectable viral load and hence might also be at risk of transmitting HIV. 2633 (25%) of 10 364 participants were at high risk of acquiring HIV (defined as HIV-negative MSM either reporting one or more casual UAI partners in the past year or not exclusively serosorting). The proportions of MSM at risk of transmission or acquisition changed little over time (p=0·96 for MSM potentially at risk of transmission and p=0·275 for MSM at high risk of acquiring HIV). Undiagnosed men reporting UAI and diagnosed men not exclusively serosorting had consistently higher partner numbers than did other MSM over the period (median ranged from one to three across surveys in undiagnosed men reporting UAI, two to ten in diagnosed men not exclusively serosorting, and none to two in other men). INTERPRETATION: An increasing proportion of undiagnosed HIV infections in MSM in London might have been recently acquired, which is when people are likely to be most infectious. High UAI partner numbers of MSM at risk of transmitting HIV and the absence of a significant decrease in the proportion of men at high risk of acquiring the infection might explain the sustained HIV incidence. Implementation of combination prevention interventions comprising both behavioural and biological interventions to reduce community-wide risk is crucial to move towards eradication of HIV. FUNDING: Public Health England.


Subject(s)
HIV Infections/epidemiology , HIV Infections/transmission , Homosexuality, Male , Sexual Behavior , AIDS Serodiagnosis , Adult , Cross-Sectional Studies , England/epidemiology , HIV Infections/diagnosis , HIV Infections/virology , Humans , London/epidemiology , Male , Mass Screening , Middle Aged , Risk-Taking , Surveys and Questionnaires
13.
Support Care Cancer ; 23(9): 2687-94, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25663575

ABSTRACT

PURPOSE: Neutropenic sepsis (NS) is a medical emergency in which urgent treatment with antibiotics is known to improve outcomes, yet there are minimal data about what happens to patients with NS before they reach hospital. We aimed to examine the pre-hospital experiences of patients with NS, identifying its early presenting features and exploring the factors potentially delaying patients' arrival at hospital. METHODS: We conducted in-depth, qualitative interviews with 22 cancer patients admitted to hospital for treatment of NS and 10 patient carers. The setting was a tertiary referral centre in Southern England. RESULTS: Thirty seven percent of patients took over 12 h to present to hospital after symptom onset. The mean delay in presentation was 11 h (range 0-68 h). Thematic analysis of the interviews, using grounded theory, revealed wide-ranging, potentially modifiable factors delaying patients' presentation to hospital. For example, information provided to patients about NS from different sources was inconsistent, with 'mixed messages' about urgency triggering delays. All patients self-monitored their temperature and understood the implication of a fever but few appreciated the potential significance of feeling unwell in the absence of fever. Attempts to obtain treatment were sometimes thwarted by nonspecialists' failure to recognise possible neutropenia in a patient with apparently mild signs, and several patients with NS were discharged without treatment. Some patients denied their symptoms to themselves and others to avoid hospital admission; palliative patients seemed particularly prone to these attitudes, while their carers were keen to seek medical attention. CONCLUSIONS: This investigation of patients' and carers' experiences of NS identifies numerous strategies for improving patient education, support and pre-hospital management, all of which may reduce pre-hospital delays and consequently decrease morbidity and mortality from NS.


Subject(s)
Chemotherapy-Induced Febrile Neutropenia , Help-Seeking Behavior , Sepsis , Adult , Aged , Chemotherapy-Induced Febrile Neutropenia/diagnosis , Chemotherapy-Induced Febrile Neutropenia/physiopathology , Chemotherapy-Induced Febrile Neutropenia/psychology , Emergency Service, Hospital , England , Female , Hospitals , Humans , Male , Middle Aged , Neoplasms/drug therapy , Patient Admission , Patient Discharge , Qualitative Research , Sepsis/diagnosis , Sepsis/physiopathology , Sepsis/psychology , Surveys and Questionnaires
14.
J Int AIDS Soc ; 17(4 Suppl 3): 19732, 2014.
Article in English | MEDLINE | ID: mdl-25397478

ABSTRACT

INTRODUCTION: ART initiation in primary HIV infection (PHI) could reduce risk of transmission to sexual partners at a time of high viraemia, although health benefit for the individual remains unknown. We examined attitudes to early ART and associated beliefs in men who have sex with men (MSM) with PHI. MATERIALS AND METHODS: Semi-structured face-to-face in-depth interviews were conducted with 13 MSM aged ≥16 years attending a central London HIV clinic, within 12 months of date of estimated HIV seroconversion. Audio recordings of interviews were transcribed verbatim and analyzed thematically. RESULTS: Median age was 33 years (range 22-47), majority were white British (n=8), educated to university level (n=11) and were not on ART (n=10). Great diversity in ART knowledge and expectations around starting were observed, with some men assuming they would be prescribed ART immediately upon diagnosis. Deferral until CD4<350 came as a surprise and counterintuitive when put into the context of treating other diseases. For many, the decision to start ART was a balance of current and future health and quality of life. Fear of side effects was prevalent, with many believing them inevitable and a reason to avoid early ART. A perceived lack of "good quality" evidence showing a health benefit of early ART caused confusion. Avoiding the decision to start or deferring to their HIV clinician was common, however reported clinicians' views also varied. Some men voiced a desire to be proactive and start early ART to control viral replication. In these cases men also reported a belief that ART could be temporary as they expected a cure in their lifetime. Men commonly described feeling "infected" and reducing this infectiousness was seen as a major benefit of ART; not purely to reduce the risk of transmission to sexual partners but to facilitate disclosure to partners, reduce anxiety and guilt and restore sexual confidence commonly lost after HIV diagnosis. Having a long-term HIV-negative partner was a strong facilitator to starting ART to reduce transmission in the absence of good evidence of individual health benefit. CONCLUSIONS: Factors involved in the decision to start ART in PHI were complex. Uncertainty over individual health benefits in conjunction with fear of toxicities were barriers to starting ART early. By contrast ART was seen as a facilitator to disclosure, and as a way to limit the consequences of infection until a cure is found.

15.
Cell Biochem Biophys ; 68(3): 615-28, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24037715

ABSTRACT

Solid tumours undergo considerable alterations in their metabolism of nutrients in order to generate sufficient energy and biomass for sustained growth and proliferation. During growth, the tumour microenvironment exerts a number of influences (e.g. hypoxia and acidity) that affect cellular biology and the flux or utilisation of fuels including glucose. The tumour spheroid model was used to characterise the utilisation of glucose and describe alterations to the activity and expression of key glycolytic enzymes during the tissue growth curve. Glucose was avidly consumed and associated with the production of lactate and an acidified medium, confirming the reliance on glycolytic pathways and a diminution of oxidative phosphorylation. The expression levels and activities of hexokinase, phosphofructokinase-1, pyruvate kinase and lactate dehydrogenase in the glycolytic pathway were measured to assess glycolytic capacity. Similar measurements were made for glucose-6-phosphate dehydrogenase, the entry point and regulatory step of the pentose-phosphate pathway (PPP) and for cytosolic malate dehydrogenase, a key link to TCA cycle intermediates. The parameters for these key enzymes were shown to undergo considerable variation during the growth curve of tumour spheroids. In addition, they revealed that the dynamic alterations were influenced by both transcriptional and posttranslational mechanisms.


Subject(s)
Neoplasms/pathology , Spheroids, Cellular/metabolism , Spheroids, Cellular/pathology , Cell Hypoxia , Cell Line, Tumor , Cell Proliferation , Energy Metabolism , Gene Expression Regulation, Neoplastic , Glucose/metabolism , Glycolysis , Humans , Hydrogen-Ion Concentration , Models, Biological , Neoplasms/enzymology , Neoplasms/metabolism , Pentose Phosphate Pathway , Spheroids, Cellular/enzymology , Tumor Microenvironment
18.
Case Rep Hematol ; 2011: 939080, 2011.
Article in English | MEDLINE | ID: mdl-22937315

ABSTRACT

We report the case of a patient with severe systemic symptoms (weight loss, malaise, and anorexia), eosinophilic oesophagitis, and raised inflammatory markers coinciding with the use of lisinopril. The onset of symptoms occurred after the administration of lisinopril and resolved shortly after cessation of the medication. Despite thorough investigation, no other cause of the systemic inflammation and anaemia of chronic disease was found. "Drug rash with eosinophilia and systemic symptoms" (DRESSs) syndrome describes a potentially serious multiorgan inflammatory response to certain classes of drugs; this includes the use of ACE inhibitors. Although this patient did not meet strict criteria for DRESSs, the subacute inflammatory syndrome with eosinophilic organ infiltration bears similar features. ACE inhibitors should be considered in the differential diagnosis in patients with nonspecific systemic inflammation and anaemia of chronic disease where no other cause is found.

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