RESUMO
AIMS: To explore whether there is a different strength of association between self-rated health and all-cause mortality in people with type 2 diabetes across three country groupings: nine countries grouped together as 'established market economies'; Asia; and Eastern Europe. METHODS: The ADVANCE trial and its post-trial follow-up were used in this study, which included 11 140 people with type 2 diabetes from 20 countries, with a median follow-up of 9.9 years. Self-rated health was reported on a 0-100 visual analogue scale. Cox proportional hazard models were fitted to estimate the relationship between the visual analogue scale score and all-cause mortality, controlling for a range of demographic and clinical risk factors. Interaction terms were used to assess whether the association between the visual analogue scale score and mortality varied across country groupings. RESULTS: The visual analogue scale score had different strengths of association with mortality in the three country groupings. A 10-point increase in visual analogue scale score was associated with a 15% (95% CI 12-18) lower mortality hazard in the established market economies, a 25% (95% CI 21-28) lower hazard in Asia, and an 8% (95% CI 3-13) lower hazard in Eastern Europe. CONCLUSIONS: Self-rated health appears to predict 10-year all-cause mortality for people with type 2 diabetes worldwide, but this relationship varies across groups of countries.
Assuntos
Diabetes Mellitus Tipo 2 , Nível de Saúde , Mortalidade , Idoso , Ásia , Austrália , Canadá , Causas de Morte , Europa Oriental , Feminino , França , Alemanha , Humanos , Irlanda , Itália , Masculino , Pessoa de Meia-Idade , Países Baixos , Nova Zelândia , Modelos de Riscos Proporcionais , Reino Unido , Escala Visual AnalógicaRESUMO
Hypertrophic cardiomyopathy thickens heart muscles, reducing functionality and increasing risk of cardiac disease and morbidity. Genetic factors are involved, but their contribution is poorly understood. We used the hypertrophic heart rat (HHR), a unique normotensive polygenic model of cardiac hypertrophy and heart failure, to investigate the role of genes associated with monogenic human cardiomyopathy. We selected 42 genes involved in monogenic human cardiomyopathies to study: 1) DNA variants, by sequencing the whole genome of 13-wk-old HHR and age-matched normal heart rat (NHR), its genetic control strain; 2) mRNA expression, by targeted RNA-sequencing in left ventricles of HHR and NHR at 5 ages (2 days old and 4, 13, 33, and 50 wk old) compared with human idiopathic dilated cardiomyopathy data; and 3) microRNA expression, with rat microRNA microarrays in left ventricles of 2-day-old HHR and age-matched NHR. We also investigated experimentally validated microRNA-mRNA interactions. Whole-genome sequencing revealed unique variants mostly located in noncoding regions of HHR and NHR. We found 29 genes differentially expressed in at least 1 age. Genes encoding desmoglein 2 ( Dsg2) and transthyretin ( Ttr) were significantly differentially expressed at all ages in the HHR, but only Ttr was also differentially expressed in human idiopathic cardiomyopathy. Lastly, only two microRNAs differentially expressed in the HHR were present in our comparison of validated microRNA-mRNA interactions. These two microRNAs interact with five of the genes studied. Our study shows that genes involved in monogenic forms of human cardiomyopathies may also influence polygenic forms of the disease.
Assuntos
Cardiomegalia/genética , Cardiomiopatias/genética , Herança Multifatorial/genética , Animais , Sítios de Ligação , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Miocárdio/metabolismo , Miocárdio/patologia , Polimorfismo de Nucleotídeo Único/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Análise de Sequência de DNARESUMO
AIMS: The relationship between educational level and the risk of all-cause mortality is well established, whereas the association with vascular events in individuals with type 2 diabetes is not well described. Any association may reflect a link with common cardiovascular or lifestyle-based risk factors. METHODS: The relationships between the highest level of educational attainment and major cardiovascular events, microvascular complications and all-cause mortality were explored in a cohort of 11,140 individuals with type 2 diabetes. Completion of formal education before the age of 16 was categorized as a low level of education. Regional differences between Asia, East Europe and Established Market Economies were also assessed. RESULTS: During a median of 5years of follow up, 1031 (9%) patients died, 1147 (10%) experienced a major cardiovascular event and 1136 (10%) a microvascular event. After adjustment for baseline characteristics and risk factors, individuals with lower education had an increased risk of cardiovascular events (hazard ratio (HR) 1.31, 95% CI 1.16-1.48, p<0.0001), microvascular events (HR 1.23, 95% CI 1.08-1.39, p=0.0013) and all-cause mortality (HR 1.34, 95% CI 1.18-1.52, p<0.0001). In regional analyses the increased risk of studied outcomes associated with lower education was weakest in Established Market Economies and strongest in East Europe. CONCLUSIONS: A low level of education is associated with an increased risk of vascular events and death in patients with type 2 diabetes, independently of common lifestyle associated cardiovascular risk factors. The effect size varies between geographical regions.
Assuntos
Doenças Cardiovasculares/etiologia , Diabetes Mellitus Tipo 2/complicações , Escolaridade , Idoso , Doenças Cardiovasculares/mortalidade , Estudos de Coortes , Diabetes Mellitus Tipo 2/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
AIMS: There is limited evidence regarding the association between physical activity and vascular complications, particularly microvascular disease, in patients with type 2 diabetes. METHODS: From the 11 140 patients in the ADVANCE (Action in Diabetes and Vascular Disease: Preterax and Diamicron modified release Controlled Evaluation) trial, the effect of physical activity, categorized as none, mild, moderate or vigorous, and the number of sessions within a week, was examined in multivariable regression models adjusted for potential confounders. The study end-points were major cardiovascular events, microvascular complications and all-cause mortality. RESULTS: Forty-six percent of participants reported undertaking moderate to vigorous physical activity for >15 min at least once in the previous week. During a median of 5 years of follow-up, 1031 patients died, 1147 experienced a major cardiovascular event and 1136 a microvascular event. Compared to patients who undertook no or mild physical activity, those reporting moderate to vigorous activity had a decreased risk of cardiovascular events (HR: 0.78, 95% CI: 0.69-0.88, p < 0.0001), microvascular events (HR: 0.85, 95% CI: 0.76-0.96, p = 0.010) and all-cause mortality (HR: 0.83, 95% CI: 0.73-0.94, p = 0.0044). CONCLUSIONS: Moderate to vigorous, but not mild, physical activity is associated with a reduced incidence of cardiovascular events, microvascular complications and all-cause mortality in patients with type 2 diabetes.
Assuntos
Diabetes Mellitus Tipo 2/terapia , Angiopatias Diabéticas/prevenção & controle , Exercício Físico , Atividade Motora , Doenças Vasculares/prevenção & controle , Idoso , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/fisiopatologia , Doenças Cardiovasculares/prevenção & controle , Estudos de Coortes , Terapia Combinada , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/mortalidade , Angiopatias Diabéticas/epidemiologia , Angiopatias Diabéticas/etiologia , Angiopatias Diabéticas/fisiopatologia , Feminino , Seguimentos , Humanos , Hipoglicemiantes/uso terapêutico , Incidência , Masculino , Microcirculação/efeitos dos fármacos , Pessoa de Meia-Idade , Mortalidade , Modelos de Riscos Proporcionais , Risco , Comportamento Sedentário , Índice de Gravidade de Doença , Doenças Vasculares/complicações , Doenças Vasculares/epidemiologia , Doenças Vasculares/fisiopatologiaRESUMO
OBJECTIVE: Examine the association of oral disease with future dementia/cognitive decline in a cohort of people with type 2 diabetes. METHODS: A total of 11,140 men and women aged 55-88 years at study induction with type 2 diabetes participated in a baseline medical examination when they reported the number of natural teeth and days of bleeding gums. Dementia and cognitive decline were ascertained periodically during a 5-year follow-up. RESULTS: Relative to the group with the greatest number of teeth (more than or equal to 22), having no teeth was associated with the highest risk of both dementia (hazard ratio; 95% confidence interval: 1.48; 1.24, 1.78) and cognitive decline (1.39; 1.21, 1.59). Number of days of bleeding gums was unrelated to these outcomes. CONCLUSIONS: Tooth loss was associated with an increased risk of both dementia and cognitive decline.
Assuntos
Transtornos Cognitivos/etiologia , Demência/etiologia , Doenças Periodontais/complicações , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Cognição , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estudos Prospectivos , Qualidade de Vida , Risco , Fatores Sexuais , Fatores SocioeconômicosRESUMO
AIMS/HYPOTHESIS: There is conflicting evidence regarding appropriate glycaemic targets for patients with type 2 diabetes. Here, we investigate the relationship between HbA(1c) and the risks of vascular complications and death in such patients. METHODS: Eleven thousand one hundred and forty patients were randomised to intensive or standard glucose control in the Action in Diabetes and Vascular disease: Preterax and Diamicron Modified Release Controlled Evaluation (ADVANCE) trial. Glycaemic exposure was assessed as the mean of HbA(1c) measurements during follow-up and prior to the first event. Adjusted risks for each HbA(1c) decile were estimated using Cox models. Possible differences in the association between HbA(1c) and risks at different levels of HbA(1c) were explored using linear spline models. RESULTS: There was a non-linear relationship between mean HbA(1c) during follow-up and the risks of macrovascular events, microvascular events and death. Within the range of HbA(1c) studied (5.5-10.5%), there was evidence of 'thresholds', such that below HbA(1c) levels of 7.0% for macrovascular events and death, and 6.5% for microvascular events, there was no significant change in risks (all p > 0.8). Above these thresholds, the risks increased significantly: every 1% higher HbA(1c) level was associated with a 38% higher risk of a macrovascular event, a 40% higher risk of a microvascular event and a 38% higher risk of death (all p < 0.0001). CONCLUSIONS/INTERPRETATION: In patients with type 2 diabetes, HbA(1c) levels were associated with lower risks of macrovascular events and death down to a threshold of 7.0% and microvascular events down to a threshold of 6.5%. There was no evidence of lower risks below these levels but neither was there clear evidence of harm.
Assuntos
Glicemia/análise , Diabetes Mellitus Tipo 2/tratamento farmacológico , Angiopatias Diabéticas/sangue , Angiopatias Diabéticas/mortalidade , Hemoglobinas Glicadas/análise , Hiperglicemia/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Anti-Hipertensivos/uso terapêutico , Estudos de Coortes , Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/patologia , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Hipertensão/prevenção & controle , Hipoglicemiantes/uso terapêutico , Masculino , Microvasos/efeitos dos fármacos , Microvasos/patologia , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de RiscoRESUMO
BACKGROUND: Male-pattern baldness (androgenetic alopecia, AGA) is the most common form of hair loss among humans. Research has shown that it is caused by genetic factors. Numerous studies have unequivocally identified two major genetic risk loci for AGA: the X-chromosomal AR/EDA2R locus, and the PAX1/FOXA2 locus on chromosome 20. OBJECTIVES: To identify further candidate genes for AGA, and thus gain further insights into this phenotype. METHODS: A German sample of 581 severely affected cases and 617 controls was used to perform a genome-wide association study. The identified associated locus was further analysed by fine-mapping, and then independently replicated in an Australian sample. Expression and pathway analyses were performed to characterize the susceptibility gene identified. RESULTS: The most significant association signal was obtained for rs756853 (P = 1·64 × 10(-7) ), which is located intronically in the histone deacetylase 9 (HDAC9) gene. Fine-mapping and a family-based analysis revealed that rs756853 and the 6-kb distal rs2249817 were the most highly associated single nucleotide polymorphisms. The association finding was replicated in an independent Australian sample, when the analysis was restricted to severely affected cases and unaffected controls (P = 0·026). Analysis of rs2249817 in a combined sample of severely affected German and Australian cases and unaffected controls revealed a strong association signal (P = 9·09 × 10(-8) ). Tissue expression studies demonstrated HDAC9 expression in various tissues, including tissues of relevance to AGA. No strong genotypic effects were observed in genotype-specific expression or splice studies. Pathway analyses supported the hypothesis that HDAC9 plays a functional role in AGA via interaction with the AR gene. CONCLUSIONS: The present study suggests that HDAC9 is the third AGA susceptibility gene.
Assuntos
Alopecia/genética , Cromossomos Humanos Par 7/genética , Histona Desacetilases/genética , Polimorfismo de Nucleotídeo Único/genética , Proteínas Repressoras/genética , Adulto , Processamento Alternativo/genética , Estudos de Casos e Controles , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , Genótipo , Humanos , MasculinoRESUMO
AIMS: We investigated the association between alcohol consumption and diabetic retinopathy and deterioration of visual acuity in individuals with Type 2 diabetes. METHODS: We conducted a cohort analysis of 1239 participants with Type 2 diabetes aged 55-81 years enrolled in the AdRem study, a sub-study of the Action in Diabetes and Vascular Disease: Preterax and Diamicron MR Controlled Evaluation (ADVANCE) trial. Current and past consumption of wine, spirits and beer was measured by self-report. Moderate and heavy alcohol consumption was defined as 1-14 and >14 drinks/week, respectively. Diabetic retinopathy, measured by mydriatic stereoscopic seven-field retinal photography, was defined by a 2-step progression in the Early Treatment of Diabetic Retinopathy Study (ETDRS) score or the presence of any retinal vascular lesions. Deterioration of visual acuity was defined by a decrease of two lines in best vision in either eye, measured corrected, or through a pinhole using a Snellen chart. RESULTS: In a mean follow-up of 5.5 years, we identified 182 participants with a 2-step progression in the ETDRS score, 640 participants with the presence of any retinal vascular lesions and 693 participants with a deterioration of visual acuity. Current moderate consumption of alcohol, compared with no current consumption, was not associated with presence or progression of diabetic retinopathy; however, it was associated with higher risk of deterioration of visual acuity (multivariable-adjusted OR 1.83; 95% CI 1.34-2.48; P<0.001). CONCLUSIONS: Alcohol consumption is associated with increased risk of deterioration of visual acuity, but not with retinopathy in individuals with Type 2 diabetes.
Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Retinopatia Diabética/epidemiologia , Acuidade Visual/fisiologia , Idoso , Idoso de 80 Anos ou mais , Consumo de Bebidas Alcoólicas/fisiopatologia , Ásia/epidemiologia , Austrália/epidemiologia , Diabetes Mellitus Tipo 2/induzido quimicamente , Diabetes Mellitus Tipo 2/fisiopatologia , Retinopatia Diabética/induzido quimicamente , Retinopatia Diabética/fisiopatologia , Progressão da Doença , Europa (Continente)/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , América do Norte/epidemiologia , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
The aim of these analyses was to examine the efficacy of the intensive gliclazide MR-based glucose lowering regimen used in the ADVANCE trial in lowering the level of glycated haemoglobin (HbA1c). All 11,140 randomised patients were included in analyses of treatment efficacy. Treatment efficacy was also examined in subgroups defined by baseline characteristics and treatments. At the end of 5 years follow-up, the mean HbA1c was reduced from 7.5% at baseline to 6.5% in those on intensive glucose control and to 7.3% in those on standard glucose control. With intensive glucose lowering greater proportions achieved HbA1c levels of < or =7.0%, < or =6.5% and < or =6.0%. With intensive glucose lowering substantial reductions in HbA1c were observed across subgroups defined by baseline age, sex, duration of diabetes, BMI, HbA1c or treatment regimen (p<0.0001). The main independent predictors of reduction in HbA1c during follow-up were baseline HbA1c, duration of diabetes and BMI. There was no weight gain in the intensive glucose control group and severe hypoglycaemia was uncommon, though more frequent than in the standard control group. Intensive glucose control with a gliclazide MR-based regimen was well tolerated and consistently effective in lowering HbA1c across a broad range of patient with type 2 diabetes.
Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Gliclazida/uso terapêutico , Hemoglobinas Glicadas/metabolismo , Hipoglicemiantes/uso terapêutico , Idoso , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Female pattern hair loss (FPHL) is a common trait in which androgens and oestrogens may have a pathogenic role. The aromatase enzyme converts androgens to oestrogens in scalp hair follicles and is differentially expressed in balding and nonbalding scalps of women. Sequence variation in the gene encoding aromatase, CYP19A1, might influence the risk of developing FPHL. OBJECTIVES: To examine the role of CYP19A1 genetic variation in the heritability of FPHL. METHODS: We investigated associations between FPHL and 61 tag single nucleotide polymorphisms (SNPs) representing variation in and around CYP19A1 in 484 caucasian women with grades 3-5 FPHL on the Sinclair scale, and 471 caucasian women with no evidence of hair loss. RESULTS: For the tag SNP rs4646 (overall genotype frequencies: CC, 53.6%; AC, 39.3%; AA, 7.1%), the genotype CC was more frequent in women with FPHL (58.1%) than controls (48.9%) (P = 0.006). Although this result did not achieve experiment-wide significance (P < 0.001 by permutation testing), subanalyses according to sources of recruitment and ages at presentation revealed consistent patterns of association. In particular, young cases (< 40 years) had the highest frequency of the CC genotype (68.2%) among all subgroups. CONCLUSIONS: These findings suggest that the common rs4646 C allele, which has been associated previously with higher circulating oestrogen levels, might be associated with predisposition to FPHL.
Assuntos
Alopecia/genética , Aromatase/genética , Estrogênios/metabolismo , Adulto , Fatores Etários , Idoso , Alopecia/patologia , Feminino , Variação Genética , Genótipo , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genéticaRESUMO
OBJECTIVE: The apolipoprotein E (APOE) polymorphism is an established risk factor for intracerebral hemorrhage (ICH) that is related to cerebral amyloid angiopathy in the white population. Among Asian populations, although ICH represents up to one third of all strokes and has high rates of mortality and morbidity, the role of the APOE polymorphism has not been well studied. METHODS: The Perindopril Protection Against Recurrent Stroke Study (PROGRESS) was a randomized, double-blind, placebo-controlled trial of a blood pressure lowering regimen in subjects with prior cerebrovascular disease. APOE status was determined for 5,671 patients, including 2,148 Asians (38%). RESULTS: During the 3.9 years of follow-up, ICH occurred in 99 patients. Overall, carrying an epsilon 2 or epsilon 4 allele of the APOE polymorphism was associated with an adjusted hazard ratio (HR(a)) of 1.85 (95% CI = 1.24 to 2.76). In Asian patients the risk of ICH for epsilon 2 or epsilon 4 carriers was 2.11 (95% CI = 1.28 to 3.47) and 1.48 (95% CI = 0.76 to 2.87) in Europeans. Carriers of the epsilon 2 or epsilon 4 allele had an increased risk of both incident and recurrent ICH, and both cortical and deep ICH, and most risk estimates were higher in Asians than in Europeans. For both ethnic groups and for subtypes of ICH active treatment more than halved the risk of ICH and the treatment effects were not different in carriers of the epsilon 2 or epsilon 4 allele and in those with the epsilon 3 epsilon 3 genotype. CONCLUSIONS: There is a strong association between APOE genotype and the risk of intracerebral hemorrhage (ICH). In Asian patients the role of APOE polymorphisms in ICH is much broader than was previously supposed.
Assuntos
Apolipoproteínas E/genética , Hemorragia Cerebral/etnologia , Hemorragia Cerebral/genética , Idoso , Apolipoproteína E2/genética , Apolipoproteína E4/genética , Povo Asiático/etnologia , Povo Asiático/genética , Hemorragia Cerebral/epidemiologia , Método Duplo-Cego , Europa (Continente)/epidemiologia , Europa (Continente)/etnologia , Feminino , Seguimentos , Predisposição Genética para Doença/epidemiologia , Predisposição Genética para Doença/etnologia , Predisposição Genética para Doença/genética , Genótipo , Humanos , Incidência , Internacionalidade , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético/genética , Recidiva , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etnologia , Acidente Vascular Cerebral/genéticaRESUMO
BACKGROUND: Blood pressure is an important determinant of the risks of macrovascular and microvascular complications of type 2 diabetes, and guidelines recommend intensive lowering of blood pressure for diabetic patients with hypertension. We assessed the effects of the routine administration of an angiotensin converting enzyme (ACE) inhibitor-diuretic combination on serious vascular events in patients with diabetes, irrespective of initial blood pressure levels or the use of other blood pressure lowering drugs. METHODS: The trial was done by 215 collaborating centres in 20 countries. After a 6-week active run-in period, 11 140 patients with type 2 diabetes were randomised to treatment with a fixed combination of perindopril and indapamide or matching placebo, in addition to current therapy. The primary endpoints were composites of major macrovascular and microvascular events, defined as death from cardiovascular disease, non-fatal stroke or non-fatal myocardial infarction, and new or worsening renal or diabetic eye disease, and analysis was by intention-to-treat. The macrovascular and microvascular composites were analysed jointly and separately. This trial is registered with ClinicalTrials.gov, number NCT00145925. FINDINGS: After a mean of 4.3 years of follow-up, 73% of those assigned active treatment and 74% of those assigned control remained on randomised treatment. Compared with patients assigned placebo, those assigned active therapy had a mean reduction in systolic blood pressure of 5.6 mm Hg and diastolic blood pressure of 2.2 mm Hg. The relative risk of a major macrovascular or microvascular event was reduced by 9% (861 [15.5%] active vs 938 [16.8%] placebo; hazard ratio 0.91, 95% CI 0.83-1.00, p=0.04). The separate reductions in macrovascular and microvascular events were similar but were not independently significant (macrovascular 0.92; 0.81-1.04, p=0.16; microvascular 0.91; 0.80-1.04, p=0.16). The relative risk of death from cardiovascular disease was reduced by 18% (211 [3.8%] active vs 257 [4.6%] placebo; 0.82, 0.68-0.98, p=0.03) and death from any cause was reduced by 14% (408 [7.3%] active vs 471 [8.5%] placebo; 0.86, 0.75-0.98, p=0.03). There was no evidence that the effects of the study treatment differed by initial blood pressure level or concomitant use of other treatments at baseline. INTERPRETATION: Routine administration of a fixed combination of perindopril and indapamide to patients with type 2 diabetes was well tolerated and reduced the risks of major vascular events, including death. Although the confidence limits were wide, the results suggest that over 5 years, one death due to any cause would be averted among every 79 patients assigned active therapy.
Assuntos
Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diuréticos/uso terapêutico , Hipertensão/tratamento farmacológico , Indapamida/uso terapêutico , Perindopril/uso terapêutico , Idoso , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/fisiopatologia , Quimioterapia Combinada , Feminino , Humanos , Hipertensão/etiologia , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
We have previously reported a quantitative trait locus (QTL) on rat chromosome 2 that influences heart size independently of blood pressure (Left Ventricular Mass Locus 1; Lvm1). The recent release of the rat genome sequence allowed us to retest and refine this relatively broad QTL with a view to identifying within it candidate genes worthy of structural investigation. We sought to achieve this 'fine mapping' by increasing the marker density within the interval and undertaking a linkage analysis in a previously defined population of F2 hybrids generated from inbred spontaneously hypertensive rats (SHR) of the Okamoto strain and Fischer rat (F344) progenitors. We were able to reconfirm and resolve Lvm1 from its original width of approximately 45 to 15 cM. By reference to the ENSEBL rat genome data bank, we identified within Lvm1 27 known genes, 109 predicted genes and 7 pseudogenes. Of the known genes, candidates include potential regulators of cardiac growth, a sodium channel and calcium channel as well as the fibroblast growth factor 2 gene. Located nearby the Lvm1 locus was the gene for the angiotensin Type 1B receptor. Given the evidence that the ligand for the angiotensin Type 1B receptor-angiotensin II-is a potent cardiotroph, we also consider this gene a potential candidate. The identification of the precise allelic variant(s) within Lvm1 involved in the control of pressure-independent cardiac growth awaits further molecular studies.
Assuntos
Pressão Sanguínea/fisiologia , Mapeamento Físico do Cromossomo , Locos de Características Quantitativas/genética , Animais , Ligação Genética , Marcadores Genéticos/genética , Humanos , Hipertrofia Ventricular Esquerda/genética , Hipertrofia Ventricular Esquerda/patologia , Tamanho do Órgão/genética , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos SHR , Receptor Tipo 2 de Angiotensina/genéticaRESUMO
The determination of human adult height is dependent on both environmental and genetic factors. Rare causes of abnormal stature have been identified, including mutations in the gene encoding aromatase (CYP19) and regions on the Y chromosome. However, the possible role of these loci in the genetic control of normal adult height is unknown. We have performed an association study using common biallelic polymorphisms within CYP19 and the Y chromosome to determine whether these loci are associated with variation in height in 413 adult males and 335 females drawn at random from a large population sample. An association between CYP19 and height was found (difference, 2.0 cm; 95% confidence interval, 0.16-3.8; P = 0.003), but this was more evident in men (difference, 2.3 cm; 95% confidence interval, 0.38-4.4; P = 0.05) than women (difference, 0.2 cm; 95% confidence interval, -2.1 to 1.6; P = 0.94). An association was also found with the Y chromosome (P = 0.009; difference of 1.9 cm; 95% confidence interval, 0.5-3.4). Additionally, when men were grouped according to haplotypes of the CYP19 and Y chromosome polymorphisms, a difference of 4.2 cm (95% confidence interval, 0.67-7.3) was detected (P = 0.004). These results suggest that in men, genetic variation in CYP19 and on the Y chromosome are involved in determining normal adult height, and that these loci may interact in an additive fashion.
Assuntos
Aromatase/genética , Estatura/genética , Cromossomo Y/genética , Adolescente , Adulto , Alelos , Feminino , Haplótipos , Humanos , Masculino , Fenótipo , Polimorfismo Genético/genética , Polimorfismo de Fragmento de Restrição , PopulaçãoRESUMO
Left ventricular hypertrophy is an independent cardiovascular risk factor. In hypertensives, the pattern of hypertrophy is influenced by central haemodynamic characteristics. Central haemodynamics may also determine physiological differences in left ventricular structure and predispose to particular responses of the left ventricle to pathological increases in load. M-mode echocardiography was used to measure left ventricular diastolic dimension and to estimate left ventricular mass index, relative wall thickness and stroke volume in 159 healthy volunteers aged between 19 and 74 years. Tonometric sphygmography was used to estimate augmentation index, central end-systolic and mean arterial blood pressure. Effective arterial elastance was calculated as the ratio of end-systolic pressure to stroke volume. Left ventricular mass index and relative wall thickness were adjusted for variation in age, sex and blood pressure before analyses. Left ventricular diastolic dimension exhibited significant inverse correlations with both effective arterial elastance (r=-0.72, P<0.0001) and augmentation index (r=-0.23, P=0.004). Adjusted left ventricular mass index was inversely correlated with effective arterial elastance (r=-0.35, P<0.0001), but no correlation was observed between left ventricular mass index and augmentation index (r=0.04). Adjusted relative wall thickness correlated with increasing effective arterial elastance (r=0.32, P<0.0001) and augmentation index (r=0.18, P=0.02). Relative wall thickness (r=0.34, P<0.0001), but not left ventricular mass index, correlated with age. Higher elastance and augmentation correlates with relatively smaller left ventricular cavity size but larger relative wall thickness. Age-related changes in left ventricular afterload may affect relative wall thickness more significantly than left ventricular mass index and may contribute to a particular change in left ventricular geometry with age.