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This study describes computer simulations of carbonization and graphite formation, including the effects of hydrogen, nitrogen, oxygen, and sulfur. We introduce a novel technique to simulate carbonization, 'Simulation of Thermal Emission of Atoms and Molecules (STEAM)', designed to elucidate volatile outgassing and density variations in the intermediate material during carbonization. The investigation analyzes the functional groups that endure through high-temperature carbonization and examines the graphitization processes in carbon-rich materials containing non-carbon impurity elements. The physical, vibrational, and electronic attributes of impure amorphous graphite are analyzed, and the impact of nitrogen on electronic conduction is investigated.
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Hypertension (HTN) is a significant risk factor for cardiovascular morbidity and mortality. Metabolic abnormalities, including adverse cholesterol and triglycerides (TG) profiles, are frequent comorbid findings with HTN and contribute to cardiovascular disease. Diuretics, which are used to treat HTN and heart failure, have been associated with worsening of fasting lipid concentrations. Genome-wide meta-analyses with 39,710 European-ancestry (EA) individuals and 9925 African-ancestry (AA) individuals were performed to identify genetic variants that modify the effect of loop or thiazide diuretic use on blood lipid concentrations. Both longitudinal and cross sectional data were used to compute cohort-specific interaction results, which were then combined through meta-analysis in each ancestry. These ancestry-specific results were further combined through trans-ancestry meta-analysis. Analysis of EA data identified two genome-wide significant (p < 5 × 10-8) loci with single nucleotide variant (SNV)-loop diuretic interaction on TG concentrations (including COL11A1). Analysis of AA data identified one genome-wide significant locus adjacent to BMP2 with SNV-loop diuretic interaction on TG concentrations. Trans-ancestry analysis strengthened evidence of association for SNV-loop diuretic interaction at two loci (KIAA1217 and BAALC). There were few significant SNV-thiazide diuretic interaction associations on TG concentrations and for either diuretic on cholesterol concentrations. Several promising loci were identified that may implicate biologic pathways that contribute to adverse metabolic side effects from diuretic therapy.
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Negro ou Afro-Americano/genética , Diuréticos/sangue , Variação Genética/genética , Hipertensão/sangue , Hipertensão/genética , População Branca/genética , Diuréticos/efeitos adversos , Estudo de Associação Genômica Ampla , Humanos , Hipertensão/tratamento farmacológico , Lipídeos/sangueRESUMO
We fabricate 2D photonic crystals (2DPC) by spreading a dispersion of charged colloidal particles (diameters = 409, 570, and 915 nm) onto the surface of electrolyte solutions using a needle tip flow method. When the interparticle electrostatic interaction potential is large, particles self-assemble into highly ordered hexagonal close packed (hcp) monolayers. Ordered 2DPC efficiently forward diffract monochromatic light to produce a Debye ring on a screen parallel to the 2DPC. The diameter of the Debye ring is inversely proportional to the 2DPC particle spacing, while the Debye ring brightness and thickness depends on the 2DPC ordering. The Debye ring thickness increases as the 2DPC order decreases. The Debye ring ordering measurements of 2DPC attached to glass slides track measurements of the 2D pair correlation function order parameter calculated from SEM micrographs. The Debye ring method was used to investigate the 2DPC particle spacing, and ordering at the air-solution interface of NaCl solutions, and for 2DPC arrays attached to glass slides. Surprisingly, the 2DPC ordering does not monotonically decrease as the salt concentration increases. This is because of chloride ion adsorption onto the anionic particle surfaces. This adsorption increases the particle surface charge and compensates for the decreased Debye length of the electric double layer when the NaCl concentration is below a critical value.
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We conducted a population-based case-control study to assess the myocardial infarction (MI) and stroke risks associated with sulphonylureas and insulin when used in combination with metformin. Cases had type 2 diabetes and used metformin + insulin or metformin + sulphonylureas at the time of a first MI or first stroke between 1995 and 2010; controls used the same treatment combinations and were randomly sampled from the same population. MI and stroke diagnoses and potential confounders were validated by medical record reviews. Compared with metformin + sulphonylurea, metformin + insulin was associated with similar risks of MI or stroke [odds ratio 0.98 (95% confidence interval 0.63-1.52)]. Meta-analysis with another observational study improved the precision of the risk estimate [relative risk 0.92 (95% confidence interval 0.69-1.24)]. Current evidence suggests that there may not be large differences in cardiovascular risk associated with the use of insulin or sulphonylureas when used in combination with metformin.
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Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Metformina/uso terapêutico , Infarto do Miocárdio/prevenção & controle , Acidente Vascular Cerebral/prevenção & controle , Compostos de Sulfonilureia/uso terapêutico , Idoso , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/induzido quimicamente , Angiopatias Diabéticas/complicações , Angiopatias Diabéticas/epidemiologia , Angiopatias Diabéticas/prevenção & controle , Cardiomiopatias Diabéticas/induzido quimicamente , Cardiomiopatias Diabéticas/complicações , Cardiomiopatias Diabéticas/epidemiologia , Cardiomiopatias Diabéticas/prevenção & controle , Quimioterapia Combinada/efeitos adversos , Feminino , Humanos , Hipoglicemiantes/efeitos adversos , Incidência , Insulina/efeitos adversos , Masculino , Prontuários Médicos , Metformina/efeitos adversos , Pessoa de Meia-Idade , Infarto do Miocárdio/induzido quimicamente , Infarto do Miocárdio/complicações , Infarto do Miocárdio/epidemiologia , Guias de Prática Clínica como Assunto , Modelos de Riscos Proporcionais , Fatores de Risco , Acidente Vascular Cerebral/induzido quimicamente , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/epidemiologia , Compostos de Sulfonilureia/efeitos adversos , Washington/epidemiologiaRESUMO
AIMS/HYPOTHESES: Despite oral hypoglycaemic medications being the most commonly used pharmacological treatments for type 2 diabetes, research is limited on their comparative safety, particularly their effects on overall mortality. We compared mortality risk with monotherapy initiation of four oral hypoglycaemic medications in a nationwide cohort of US veterans with type 2 diabetes. METHODS: We identified new users of oral hypoglycaemic medication monotherapy between 2004 and 2009 who received care for at least 1 year from the Veterans Health Administration.Patients were followed until initial monotherapy discontinuation,addition of another diabetes pharmacotherapy, death or end of follow-up. Mortality HRs were estimated using Cox regression adjusted for potential confounding factors. RESULTS: Among new users of metformin, sulfonylureas and rosiglitazone (185,360 men, 7,812 women), 4,256 (2.2%) died during follow-up. Average duration of medication use ranged from 1.4 to 1.7 years. Significantly higher mortality risk was seen for glibenclamide (known as glyburide in the USA and Canada) (HR 1.38, 95% CI 1.27, 1.50) or glipizide (HR 1.55,95% CI 1.43, 1.67) compared with metformin monotherapy,and for glipizide compared with rosiglitazone (HR 1.27, 95%CI 1.01, 1.59) or glibenclamide monotherapy (HR 1.12, 95%CI 1.02, 1.23). A significant sexrosiglitazone interaction was seen (p=0.034) compared with metformin monotherapy, with women having a higher HR (HR 4.36, 95% CI 1.34, 14.20)than men (HR 1.19, 95% CI 0.95, 1.49). CONCLUSIONS/INTERPRETATIONS: Significantly higher mortality was associated with glibenclamide, glipizide and rosiglitazone use compared with metformin, and with glipizide use compared with rosiglitazone or glibenclamide. The potential for residual confounding by indication should be considered in interpreting these results.
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Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Metformina/administração & dosagem , Compostos de Sulfonilureia/administração & dosagem , Tiazolidinedionas/administração & dosagem , Veteranos/estatística & dados numéricos , Diabetes Mellitus Tipo 2/mortalidade , Feminino , Seguimentos , Glipizida/administração & dosagem , Glipizida/efeitos adversos , Glibureto/administração & dosagem , Glibureto/efeitos adversos , Humanos , Hipoglicemiantes/efeitos adversos , Masculino , Metformina/efeitos adversos , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Rosiglitazona , Compostos de Sulfonilureia/efeitos adversos , Tiazolidinedionas/efeitos adversos , Fatores de Tempo , Estados Unidos/epidemiologiaRESUMO
Several studies suggest mannose-binding lectin (MBL) deficiency is associated with various manifestations of aspergillosis. MBL serum levels and function are genetically determined, but levels rise during inflammation. We address the relative frequency of deficient genotypes, the relationship between serum level and genotype and both age and disease manifestations in patients with chronic pulmonary (CPA) and allergic bronchopulmonary aspergillosis (ABPA) and severe asthma with fungal sensitization (SAFS). DNA was extracted from blood samples, and MBL2 genotyping was performed using the INNO-LiPA MBL2 kit. Serum MBL concentrations were determined using ELISA. One hundred and eight patients were evaluated, 70 (65%) with CPA, 38 (35%) with allergic disease (ABPA, SAFS or undefined) and 13 (12%) had both CPA and ABPA. The mean MBL serum level was 1849 µg L(-1) and did not differ between groups. Forty subjects (37%) had exon 1 genotypes producing nonfunctional MBL (A/B, A/C, A/D and O/O), a frequency not different from published normal controls. A/A subjects with CPA had higher levels (2981 µg L(-1)) compared with allergic A/A subjects (2202 µg L(-1)) (pc0.012). No single haplotype, genotype or allele was significantly related to any aspergillosis phenotype. Worse breathlessness was associated with higher MBL levels among A/A subjects (P = 0.009) and conversely nonfunctional genotypes. Mean MBL values were higher in those with an Medical Research Council (MRC) breathlessness score of 5 compared with those with and MRC score of 1 (P = 0.023). A/A allergic subjects (n = 27) in this study were ≈ 11 years younger than allergic A/O subjects (n = 11, P = 0.02). Subjects with worse respiratory status or more severe CPA had higher MBL serum levels (P = 0.023; P = 0.034). Bronchiectasis was not associated with MBL levels in CPA or allergic aspergillosis. MBL genotype and serum level modulate progression of aspergillosis.
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Aspergilose Broncopulmonar Alérgica/genética , Lectina de Ligação a Manose/genética , Polimorfismo de Nucleotídeo Único , Aspergilose Pulmonar/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Aspergilose Broncopulmonar Alérgica/sangue , Doença Crônica , Ensaio de Imunoadsorção Enzimática , Frequência do Gene , Estudos de Associação Genética , Genótipo , Técnicas de Genotipagem/métodos , Haplótipos , Humanos , Desequilíbrio de Ligação , Lectina de Ligação a Manose/sangue , Pessoa de Meia-Idade , Fenótipo , Aspergilose Pulmonar/sangueRESUMO
Chronic pulmonary aspergillosis (CPA) is a condition caused by the ubiquitous fungus Aspergillus fumigatus in non-immunocompromised individuals. Numerous underlying conditions have been associated with CPA. Details of the underlying conditions of 126 CPA patients attending our tertiary referral clinic from all over the UK were extracted from the clinical notes, and the distribution of these underlying conditions was analysed. For those with several underlying pulmonary conditions, one was nominated as the primary condition. Many patients presented with multiple underlying conditions, and a total of 232 underlying conditions were identified for the 126 patients. Previous classical tuberculosis and non-tuberculous mycobacterial infection were the most common primary underlying conditions (15.3% and 14.9%, respectively). Others included allergic bronchopulmonary aspergillosis (ABPA), chronic obstructive pulmonary condition (COPD) and/or emphysema, pneumothorax and prior treated lung cancer. Some conditions were found more often as one of multiple underlying conditions, while others were found only as secondary underlying conditions. Tuberculosis, non-tuberculous mycobacterial infection and ABPA remain the predominant risk factors for development of CPA, with COPD, prior pneumothorax or treated lung cancer also relatively common among our referrals. Many patients have multiple underlying pulmonary conditions. CPA should be considered when upper lobe cavitary or fibrotic disease and systemic symptoms are present in those with lung disease.
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Aspergilose/diagnóstico , Aspergillus fumigatus/metabolismo , Aspergilose Pulmonar/diagnóstico , Aspergilose Pulmonar/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Aspergilose/complicações , Enfisema/terapia , Feminino , Humanos , Itraconazol/farmacologia , Neoplasias Pulmonares/complicações , Masculino , Pessoa de Meia-Idade , Pneumotórax/terapia , Aspergilose Pulmonar/complicações , Doença Pulmonar Obstrutiva Crônica/terapia , Reino UnidoRESUMO
BACKGROUND: Immunosuppressed patients are at increased risk for herpes zoster (HZ), but incidence in solid organ transplant (SOT) recipients has varied in multiple studies. To assess incidence of HZ, we examined patients who underwent SOT and received follow-up care within the large multicenter US Department of Veteran's Affairs healthcare system. METHODS: Incident cases of HZ were determined using ICD-9 coding from administrative databases. A multivariable Cox proportional hazards model, adjusted for a priori risk factors, was used to assess demographic factors associated with development of HZ. RESULTS: Among the 1077 eligible SOT recipients, the cohort-specific incidence rate of HZ was 22.2 per 1000 patient-years (95% confidence interval [CI], 18.1-27.4). African Americans (37.6 per 1000 [95% CI, 25.0-56.6]) and heart transplants recipients (40.0 per 1000 [95% CI, 23.2-68.9]) had the highest incidence of HZ. Patients transplanted between 2005 and 2007 had the lowest incidence (15.3 per 1000 [95% CI, 8.2-28.3]). In a multivariable model, African Americans (hazard ratio [HR] 1.88; 95% CI: 1.12, 3.17) and older transplant recipients (HR 1.13; 95% CI: 1.01, 1.27 [per 5-year increment]) had increased relative hazards of HZ. CONCLUSIONS: These data demonstrate that HZ is a common infectious complication following SOT. Future studies focused on HZ prevention are needed in this high-risk population.
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Herpes Zoster/epidemiologia , Herpesvirus Humano 3 , Transplante de Órgãos/efeitos adversos , Negro ou Afro-Americano , Estudos de Coortes , Feminino , Transplante de Coração/efeitos adversos , Herpes Zoster/diagnóstico , Herpes Zoster/etnologia , Herpes Zoster/virologia , Humanos , Incidência , Classificação Internacional de Doenças , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de RiscoRESUMO
BACKGROUND: Arterial thrombosis involves platelet aggregation and clot formation, yet little is known about the contribution of genetic variation in fibrin-based hemostatic factors to arterial clotting risk. We hypothesized that common variation in 24 coagulation-fibrinolysis genes would contribute to risk of incident myocardial infarction (MI) or ischemic stroke (IS). METHODS: We conducted a population-based, case-control study. Subjects were hypertensive adults and postmenopausal women 30-79 years of age, who sustained a first MI (n = 856) or IS (n = 368) between 1995 and 2002, and controls matched on age, hypertension status, and calendar year (n = 2,689). We investigated the risk of MI and IS associated with (i) global variation within each gene as measured by common haplotypes and (ii) individual haplotypes and single nucleotide polymorphisms (SNPs). Significance was assessed using a 0.2 threshold of the false discovery rate q-value, which accounts for multiple testing. RESULTS: After accounting for multiple testing, global genetic variation in factor (F) VIII was associated with IS risk. Two haplotypes in FVIII and one in FXIIIa1 were significantly associated with increased IS risk (all q-values < 0.2). A plasminogen gene SNP was associated with MI risk. All are new discoveries not previously reported. Another 24 tests had P-values < 0.05 and q-values > 0.2 in MI and IS analyses, 23 of which are new and hypothesis generating. CONCLUSIONS: Apart from the association of FVIII variation with IS, we found little evidence that common variation in the 24 candidate fibrin-based hemostasis genes strongly influences arterial thrombotic risk, but our results cannot rule out small effects.
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Fator VIII/genética , Fator XIIIa/genética , Variação Genética , Hemostasia/genética , Infarto do Miocárdio/genética , Plasminogênio/genética , Acidente Vascular Cerebral/genética , Idoso , Estudos de Casos e Controles , Haplótipos , Humanos , Hipertensão , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Pós-MenopausaRESUMO
BACKGROUND: Atrial fibrillation (AF) is a common arrhythmia that affects more than 2 million people in the United States. We sought to determine whether the risk of incident AF among patients treated for hypertension differs by the degree of blood pressure control. METHODS: A population-based, case-control study of 433 patients with verified incident AF and 899 controls was conducted to investigate the relationship between average achieved systolic (SBP) and diastolic (DBP) blood pressure and risk of AF. All patients were members of an integrated health-care delivery system and were pharmacologically treated for hypertension. Medical records were reviewed to confirm the diagnosis of new onset AF and to collect information on medical conditions, health behaviors, and measured blood pressures. Average achieved SBP and DBP were calculated from the three most recent outpatient blood pressure measurements. RESULTS: Compared with the reference level of 120-129 mm Hg, for categories of average achieved SBP of <120, 130-139, 140-149, 150-159, 160-169, and > or =170 mm Hg, the odds ratios (ORs; 95% confidence interval (CI)) for incident AF were 1.99 (1.10, 3.62), 1.19 (0.78, 1.81), 1.40 (0.93, 2.09), 2.02 (1.30, 3.15), 2.27 (1.31, 3.93), and 1.84 (0.89, 3.80), respectively. Based on the population attributable fraction, we estimated that, among patients with treated hypertension, 17.2% (95% CI 4.3%, 28.3%) of incident AF was attributable to an average achieved SBP > or =140 mm Hg. CONCLUSION: Among patients treated for hypertension, uncontrolled elevated SBP and SBP <120 mm Hg were associated with an increased risk of incident AF.
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Fibrilação Atrial/epidemiologia , Monitorização Ambulatorial da Pressão Arterial/métodos , Pressão Sanguínea/fisiologia , Idoso , Anti-Hipertensivos/uso terapêutico , Fibrilação Atrial/etiologia , Fibrilação Atrial/fisiopatologia , Eletrocardiografia , Feminino , Seguimentos , Humanos , Hipertensão/complicações , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Incidência , Masculino , Razão de Chances , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Washington/epidemiologiaRESUMO
Essentials Vasomotor symptoms have been proposed as markers of changing cardiovascular risk. In this cohort study, we evaluated these symptoms as markers of venous thrombosis (VT) risk. We found no evidence that vasomotor symptom presence or severity were associated with VT risk. Among these postmenopausal women, vasomotor symptoms are not a useful marker of VT risk. SUMMARY: Background Vasomotor symptoms may be markers of changes in cardiovascular risk, but it is unknown whether these symptoms are associated with the risk of venous thrombosis (VT). Objective To evaluate the association of vasomotor symptom presence and severity with incident VT risk among postmenopausal women, independent of potential explanatory variables. Methods This cohort study included participants of the Women's Health Initiative (WHI) Hormone Therapy Trials (n = 24 508) and Observational Study (n = 87 783), analyzed separately. At baseline, women reported whether hot flashes or night sweats were present and, if so, their severity. Using Cox proportional hazards models, we estimated the VT risk associated with vasomotor symptom presence and severity, adjusted for potential explanatory variables: age, body mass index, smoking status, race/ethnicity, and time-varying current hormone therapy use. Results At baseline, WHI Hormone Therapy Trial participants were aged 64 years and WHI Observational Study participants were aged 63 years, on average. In the WHI Hormone Therapy Trials over a median of 8.2 years of follow-up, 522 women experienced a VT event. In the WHI Observational Study, over 7.9 years of follow-up, 1103 women experienced a VT event. In adjusted analyses, we found no evidence of an association between vasomotor symptom presence (hazard ratio [HR]adj 0.91, 95% confidence interval [CI] 0.75-1.1 in the WHI Hormone Therapy Trials; HRadj 1.1, 95% CI 0.99-1.3 in the WHI Observational Study) or severity (HRadj for severe versus mild 0.99, 95% CI 0.53-1.9 in the WHI Hormone Therapy Trials; HRadj 1.3, 95% CI 0.89-2.0) in the WHI Observational Study) and the risk of incident VT. Conclusions Although vasomotor symptoms have been associated with the risk of other cardiovascular events in published studies, our findings do not suggest that vasomotor symptoms constitute a marker of VT risk.
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Fogachos/epidemiologia , Pós-Menopausa , Sudorese , Sistema Vasomotor/fisiopatologia , Trombose Venosa/epidemiologia , Idoso , Feminino , Fogachos/diagnóstico , Fogachos/fisiopatologia , Humanos , Incidência , Pessoa de Meia-Idade , Estudos Observacionais como Assunto , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Estados Unidos/epidemiologia , Trombose Venosa/diagnóstico , Trombose Venosa/fisiopatologiaRESUMO
Essentials Endogenous hormone levels' influence on hemostatic factor levels is not fully characterized. We tested for associations of endogenous hormone with hemostatic factor levels in postmenopause. Estrone levels were inversely associated with the natural anticoagulant, protein S antigen. Dehydroepiandrosterone sulfate levels were inversely associated with thrombin generation. SUMMARY: Background Oral use of exogenous estrogen/progestin alters hemostatic factor levels. The influence of endogenous hormones on these levels is incompletely characterized. Objectives Our study aimed to test whether, among postmenopausal women, high levels of estradiol (E2), estrone (E1), testosterone (T), dehydroepiandrosterone sulfate (DHEAS), dehydroepiandrosterone (DHEA), and androstenedione, and low levels of sex hormone-binding globulin (SHBG), are positively associated with measures of thrombin generation (TG), a normalized activated protein C sensitivity ratio (nAPCsr), and factor VII activity (FVIIc), and negatively associated with antithrombin activity (ATc) and total protein S antigen (PSAg). Methods This Heart and Vascular Health study cross-sectional analysis included 131 postmenopausal women without a prior venous thrombosis who were not currently using hormone therapy. Adjusted mean differences in TG, nAPCsr, FVIIc, ATc and PSAg levels associated with differences in hormone levels were estimated using multiple linear regression. We measured E2, E1, total T, DHEAS, DHEA and androstenedione levels by mass spectrometry, SHBG levels by immunoassay, and calculated the level of free T. Results One picogram per milliliter higher E1 levels were associated with 0.24% lower PSAg levels (95% Confidence Interval [CI]: -0.35, -0.12) and 1 µg mL-1 higher DHEAS levels were associated with 40.8 nm lower TG peak values (95% CI: -59.5, -22.2) and 140.7 nm×min lower TG endogenous thrombin potential (ETP) (95% CI: -212.1, -69.4). After multiple comparisons correction, there was no evidence for other associations. Conclusions As hypothesized, higher E1 levels were associated with lower levels of the natural anticoagulant PSAg. Contrary to hypotheses, higher DHEAS levels were associated with differences in TG peak and ETP that suggest less generation of thrombin.
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Hemostasia , Pós-Menopausa/sangue , Globulina de Ligação a Hormônio Sexual/metabolismo , Esteroides/sangue , Trombose/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Androstenodiona/sangue , Antitrombinas/metabolismo , Estudos Transversais , Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona/sangue , Estradiol/sangue , Estrona/sangue , Fator VII/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade , Proteína C/metabolismo , Proteína S/metabolismo , Testosterona/sangue , Trombina/metabolismo , Adulto JovemRESUMO
OBJECTIVES: Clinical trials have demonstrated that oral conjugated equine estrogen (CEE) therapy with or without medroxyprogesterone (MPA) increases venous thrombotic risk but this safety issue has not been investigated for other oral estrogens. Based on observational study findings that esterified estrogen (EE) was not associated with venous thrombotic risk whereas CEE was, we hypothesized that CEE users would be more resistant to activated protein C (APC), a prothrombotic phenotype, than EE users. METHODS: We conducted an observational, cross-sectional study of postmenopausal women 30-89 years old who were controls in a case-control study of venous thrombosis. Use of CEE, EE, and MPA at the time of phlebotomy was determined using computerized pharmacy records. APC resistance was measured in plasma by the endogenous thrombin potential normalized APC sensitivity ratio. Adjusted mean APC resistance values were compared across estrogen type and CEE:EE ratios are presented. RESULTS: There were 119 CEE and 92 EE users at the time of phlebotomy. Compared with EE users, CEE users had APC resistance measures that were 52% higher (1.52; 95% confidence intervals: 1.07-2.17) in adjusted analyses. Restricting to modal dose users (0.625 mg) and stratifying by MPA use did not materially change associations. CONCLUSIONS: CEE use was associated with higher levels of APC resistance when compared with EE use in postmenopausal women. These findings might provide an explanation for the higher risk of venous thromboembolism previously observed with CEE compared with EE use and, if replicated, may have safety implications for women when choosing an estrogen for symptom relief.
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Resistência à Proteína C Ativada/metabolismo , Estrogênios Conjugados (USP)/metabolismo , Estrogênios Esterificados (USP)/metabolismo , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Ensaios Clínicos como Assunto , Terapia de Reposição de Estrogênios , Estrogênios Conjugados (USP)/administração & dosagem , Estrogênios Esterificados (USP)/administração & dosagem , Feminino , Hemostasia , Cavalos , Humanos , Pessoa de Meia-Idade , Fenótipo , Pós-Menopausa , Progestinas/metabolismo , Resultado do Tratamento , Trombose Venosa/prevenção & controleRESUMO
Growing evidence indicates that chronic exposure to Bisphenol A (BPA) may disrupt normal brain function and behavior mediated by gonadotropin-releasing hormone (GnRH) pathways. Previous studies have shown that low dose BPA (200ng/ml) exposure during embryogenesis altered development of extra-hypothalamic GnRH3 systems and non-reproductive locomotor behavior in medaka. Effects of parental low-dose BPA exposure on the development of GnRH3 systems and locomotor behavior of offspring are not well known. This study examines whether the neurophysiological and behavioral effects of BPA in parents (F0 generation) are carried over to their offspring (F1 generation) using stable transgenic medaka embryos/larvae with GnRH3 neurons tagged with green fluorescent protein (GFP). Parental fish were exposed to BPA (200ng/ml) for either life-long or different developmental time windows. Fertilized F1 eggs were collected and raised in egg/fish water with no environmental exposure to BPA. All experiments were performed on F1 embryos/larvae, which were grouped based on the following parental (F0) BPA exposure conditions - (i) Group 1 (G1): through life; (ii) G2: during embryogenesis and early larval development [1-14days post fertilization (dpf)]; (iii) G3: during neurogenesis (1-5dpf); and (iv) G4: during sex differentiation (5-14dpf). Embryos from unexposed vehicle treated parents served as controls (G0). G1 embryos showed significantly reduced survival rates and delayed hatching time compared to other groups, while G4 embryos hatched significantly earlier than all other groups. At 3 dpf, the GnRH3-GFP intensity was increased by 47% in G3 embryos and decreased in G4 embryos by 59% compared to controls. At 4dpf, G1 fish showed 42% increased intensity, while GFP intensity was reduced by 44% in G3 subjects. In addition, the mean brain size of G1, G3 and G4 embryos were smaller than that of control at 4dpf. At 20dpf, all larvae from BPA-treated parents showed significantly decreased total movement (distance covered) compared with controls, with G2 and G3 fish showing reduced velocity of movement. While at 20 dpf no group differences were seen in the soma diameter of GnRH3-GFP neurons, a 34% decrease in SV2 expression, a marker for synaptic transmission, in G1 larvae was observed. These data suggest that parental BPA exposure during critical windows of embryonic development or chronic treatment affects next-generation offspring both in embryonic and larval brain development as well as larval behavior.
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Compostos Benzidrílicos/farmacologia , Encéfalo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/metabolismo , Fenóis/farmacologia , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Ácido Pirrolidonocarboxílico/análogos & derivados , Animais , Animais Geneticamente Modificados , Encéfalo/efeitos dos fármacos , Encéfalo/embriologia , Encéfalo/crescimento & desenvolvimento , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Hormônio Liberador de Gonadotropina/genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Larva/efeitos dos fármacos , Larva/fisiologia , Oryzias/embriologia , Gravidez , Ácido Pirrolidonocarboxílico/metabolismo , Diferenciação Sexual/efeitos dos fármacosRESUMO
OBJECTIVE: To characterize the risk of postpartum venous thromboembolism (VTE) associated with body-mass-index (BMI) in both pre-pregnancy and at delivery, and with gestational weight gain (GWG). METHODS: In a population-based, case-control study, we identified all women in Washington State with ICD-9 codes for VTE in the postpartum period between 2003 and 2011. Controls were women without VTE in the postpartum period, matched by delivery year to cases. Pre-pregnancy BMI, delivery BMI, and covariates were abstracted from birth certificates. Adjusted logistic regression models separately estimated postpartum VTE risk associated with categories of BMI in pre-pregnancy and at delivery. RESULTS: Cases (n=289) had a higher mean BMI than controls (n=4208) pre-pregnancy (29.9kg/m(2) and 26.3kg/m(2), respectively) and at delivery (34.8kg/m(2) vs. 31.4kg/m(2), respectively), with similar gestational weight gains. Compared with women with a normal pre-pregnancy BMI (18.5-24.9kg/m(2)), overweight (BMI 25-29.9kg/m(2)) and obese (BMI≥30kg/m(2)) women were at a 1.5-fold and 1.8-4 fold greater risk of postpartum VTE, respectively, with greatest risks in women with class III obesity (BMI≥40kg/m(2): OR 4.0, 95%CI 2.7-6.3). Observed associations of delivery BMI with postpartum VTE were less strong than those of pre-pregnancy BMI. Large weight gains during pregnancy (>22kg) also contributed to greater VTE risks (OR 1.5, 95%CI 1.0-2.2). CONCLUSION: Maternal BMI is an important risk factor for postpartum VTE, grading from weak in overweight women to very strong in women with class III obesity. Care providers may prefer to use pre-pregnancy BMI, along gestational weight gain, when stratifying the risk of postpartum VTE at delivery.
Assuntos
Trombose Venosa/etiologia , Índice de Massa Corporal , Estudos de Casos e Controles , Feminino , Humanos , Período Pós-Parto , Gravidez , Complicações Cardiovasculares na Gravidez , Fatores de Risco , Aumento de PesoRESUMO
UNLABELLED: Essentials A lowered risk of recurrent venous thrombosis (VT) with statin treatment is controversial. Among observational inception cohort of 2,798 adults with incident VT, 457 had recurrent VT. Time-to-event models with time-varying statin use and adjustment for potential confounders was used for analysis. Compared to nonuse, current statin use was associated with 26% lower risk of recurrent VT. Click to hear Prof. Büller's perspective on Anticoagulant Therapy in the Treatment of Venous Thromboembolism SUMMARY: Background Meta-analyses of randomized controlled trials suggest that treatment with hydroxymethylglutaryl-coenzyme A reductase inhibitors (statins) lowers the risk of incident venous thrombosis (VT), particularly among those without prevalent clinical cardiovascular disease (CVD). Whether this is true for the prevention of recurrent VT is debated. We used an observational inception cohort to estimate the association of current statin use with the risk of recurrent VT. Methods and Results The study setting was a large healthcare organization with detailed medical record and pharmacy information at cohort entry and throughout follow-up. We followed 2798 subjects 18-89 years of age who experienced a validated incident VT between January 1, 2002, and December 31, 2010, for a first recurrent VT, validated by medical record review. During follow-up, 457 (16%) developed a first recurrent VT. In time-to-event models incorporating time-varying statin use and adjusting for potential confounders, current statin use was associated with a 26% lower risk of recurrent VT: hazard ratio 0.74, 95% confidence interval 0.59-0.94. Among cohort members free of CVD (n = 2134), current statin use was also associated with a lower risk (38%) of recurrent VT: hazard ratio 0.62, 95% confidence interval 0.45-0.85. We found similar results when restricting to new users of statins and in subgroups of different statin types and doses. Conclusions In a population-based cohort of subjects who had experienced an incident VT, statin use, compared with nonuse, was associated with a clinically relevant lower risk of recurrent VT. These findings suggest a potential secondary benefit of statins among patients who have experienced an incident VT.
Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Trombose Venosa/tratamento farmacológico , Trombose Venosa/prevenção & controle , Administração Oral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/uso terapêutico , Doenças Cardiovasculares/terapia , Anticoncepcionais Orais/uso terapêutico , Estrogênios/uso terapêutico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Modelos de Riscos Proporcionais , Embolia Pulmonar/tratamento farmacológico , Recidiva , Fatores de Risco , Trombose/tratamento farmacológico , Trombose Venosa/metabolismo , Adulto JovemRESUMO
OBJECTIVE: We compared long-term health outcomes associated with beta-adrenergic blocking agents and diltiazem treatment for unstable angina. BACKGROUND: No long-term data have been published comparing these two antianginal treatments in this setting. METHODS: Eligible veterans were discharged from the Veterans Affairs Puget Sound Health Care System (VAPSHCS), Seattle Division, between October 1989 and September 1995 with an unstable angina diagnosis and were prescribed monotherapy beta-blocker or diltiazem treatment at discharge. Medication data were collected from medical records and computerized VAPSHCS outpatient pharmacy files. Follow-up death and coronary artery disease rehospitalization data were collected through 1996. Proportional hazards regression compared survival among diltiazem and beta-blocker users, controlling for patient characteristics with propensity scores. RESULTS: Two hundred forty-seven veterans (24% on beta-blockers, 76% on diltiazem) were included in this study. There were 54 (22%) deaths during an average follow-up of 51 months. After propensity score adjustment, there was no difference in risk of death comparing diltiazem to beta-blocker treatment (hazards ratios [HR] 1.1; 95% confidence interval [CI] 0.49 to 2.4). Among Washington residents (n=207), there were 146 (71%) coronary artery disease rehospitalizations or deaths during follow-up. After adjustment, there was a nonsignificant increase in risk of rehospitalization or death associated with diltiazem use (HR 1.4; 95% CI 0.80 to 2.4). For both analyses, similar risks were found among veterans without relative contraindications to beta-blockers. CONCLUSIONS: We found no survival benefit of diltiazem over beta-blocker treatment for unstable angina in this cohort of veterans.
Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Angina Instável/tratamento farmacológico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Diltiazem/uso terapêutico , Angina Instável/mortalidade , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Readmissão do Paciente , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento , Washington/epidemiologiaRESUMO
BACKGROUND: Evidence from clinical trials in the past decade has consistently shown that angiotensin-converting enzyme (ACE) inhibitors reduce morbidity and mortality in patients with congestive heart failure (CHF). The extent to which clinical practice has adopted ACE inhibitor therapy is unknown. METHODS: The Cardiovascular Health Study is a prospective observational study of 5201 community-dwelling adults aged 65 years and older. Prevalent CHF cases were identified on study entry (from June 10, 1989, through May 31, 1990) and incident CHF cases were identified throughout 5 years of follow-up. Medication data were collected from annual medication inventories. The percentage of patients with CHF using ACE inhibitors was calculated at each annual examination. Temporal trends in CHF treatment with ACE inhibitors between June 10, 1989, through May 31, 1990, and June 1, 1994, through May 31, 1995, were analyzed. RESULTS: Use of ACE inhibitors to treat CHF increased slightly over time among prevalent cases at each annual examination: 26% of prevalent CHF cases were treated in 1989-1990 compared with 36% of prevalent cases in 1994-1995. This 10% increase was statistically significant (P<.01). Participants with low ejection fractions were 2 times more likely to be treated with ACE inhibitors than were those with normal ejection fraction and this tendency did not change over time. Among cases newly diagnosed in the year before the 1990-1991 examination, 42% were using ACE inhibitors; among those newly diagnosed in the year before 1994-1995, 40% were using ACE inhibitors. This 2% decrease was not statistically significant (P=.68). CONCLUSION: These findings suggest that, while the medical management of CHF with ACE inhibitors has increased modestly over time in prevalent cases, these drugs may still be underused, especially among incident cases.
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Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Idoso , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Uso de Medicamentos , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Modelos Logísticos , Masculino , Volume Sistólico/efeitos dos fármacos , Resultado do Tratamento , Estados UnidosRESUMO
BACKGROUND: There is little information about whether an increasing duration of estrogen replacement therapy is associated with a declining risk for myocardial infarction in postmenopausal women. OBJECTIVE: To conduct a population-based, case-control study among enrollees of the Group Health Cooperative (GHC) of Puget Sound, Seattle, Wash. SUBJECTS AND METHODS: Case subjects were all post-menopausal women who were enrolled in the GHC with an incident fatal or nonfatal myocardial infarction from July 1986 through December 1993. Control subjects were a stratified random sample of postmenopausal women who were enrolled in the GHC without myocardial infarction and matched to case subjects by age and calendar year. We reviewed the medical records of the 850 case subjects and 1974 control subjects and conducted telephone interviews with consenting survivors. Use of estrogen or estrogen and progestin was assessed using GHC's computerized pharmacy database. RESULTS: Among women who were currently using estrogen, a longer duration of use was inversely associated with a risk for myocardial infarction after adjustment for age, year of identification, diabetes mellitus, angina, and smoking. For categories of increasing duration of estrogen use (never, > 0-< 1.8 years, 1.8-< 4.2 years, 4.2-< 8.2 years, and > or = 8.2 years), the odds ratios for myocardial infarction were 1.00 (reference), 0.91, 0.70, 0.65, and 0.55 (for trend among the current users, P = .05). Among women who had used estrogen in the past, there was no evidence of decreasing risk with increasing duration of estrogen use. CONCLUSION: In this study, a long duration of hormone replacement therapy among women currently using estrogen was associated with a reduced risk for first myocardial infarction.