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1.
Cytokine ; 149: 155722, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34624603

RESUMO

BACKGROUND: Monocyte chemoattractant protein-1 (MCP-1) concentrations are 34% to 47% heritable. Larger -2518 G/A (rs1024611) genotypes differences are reported for: 1) MCP-1 production in stimulated vs. basal cells; and 2) MCP-1 concentrations in diseased (sepsis, brain abscess, hepatitis B virus, Alzheimer's disease, Behcet's disease, and systemic lupus erythematosus) vs. healthy patients. Those results suggest that the -2518 G/A effect size may depend on whether the phenotype is high or low relative to its distribution (quantile-dependent expressivity). METHOD: To test whether quantile-dependent expressivity applies more broadly to genetic influences on MCP-1 concentrations, quantile-specific offspring-parent (ßOP) and full-sib regression slopes (ßFS) were estimated by applying quantile regression to the age- and sex-adjusted serum MCP-1 concentrations of Framingham Heart Study families. Quantile-specific heritabilities were calculated as h2 = 2ßOP/(1 + rspouse) and h2={(1 + 8rspouseßFS)0.5-1}/(2rspouse)). RESULTS: Heritability (h2 ± SE) of MCP-1 concentrations increased from 0.15 ± 0.05 at the 10th percentile of the MCP-1 distribution, 0.23 ± 0.04 at the 25th, 0.32 ± 0.05 at the 50th, 0.43 ± 0.07 at the 75th, and 0.44 ± 0.07 at the 90th percentile, or an 0.0041 ± 0.0009 increase for each one-percent increment in the MCP-1 distribution (Plinear trend = 2.4 × 10-5) when estimated from ßOP, and (Plinear trend = 7.7 × 10-9) when estimated from ßFS. Compared to the 10th percentile, ßOP-estimated h2 was 3-fold greater at the 90th percentile (Pdifference = 0.0003), and 6.9-fold greater when estimated from ßFS (Pdifference = 3.3 × 10-6). Re-analysis of in vivo comparison of MCP-1 concentrations in controls vs. patients with MCP-1-elevating conditions, and in vitro studies of MCP-1 production in basal vs. stimulated cells, show rs1024611 genotypes differences that were consistent with quantile-dependent expressivity. CONCLUSION: The heritability of circulating MCP-1 concentrations is quantile-dependent.


Assuntos
Quimiocina CCL2/genética , Doença/genética , Adulto , Feminino , Genótipo , Humanos , Masculino , Fenótipo
2.
Growth Factors ; 39(1-6): 45-58, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35312415

RESUMO

BACKGROUND: "Quantile-dependent expressivity" occurs when the effect size of a genetic variant depends upon whether the phenotype (e.g. growth factor concentration) is high or low relative to its distribution. METHODS: Quantile-regression analysis was applied to family sets from the Framingham Heart Study to determine whether the heritability (h2) of vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), angiopoietin-2, and angiopoietin-2 (sTie-2) and VEGFR1 (sFlt-1) receptor concentrations were quantile-specific. RESULTS: Quantile-specific h2 (±SE) increased with increasing percentiles of the age- and sex-adjusted VEGF (Ptrend<10-16), HGF (Ptrend=0.0004), angiopoietin-2 (Ptrend=0.0002), sTie-2 (Ptrend=1.2 × 10-5), and sFlt-1 distributions (Ptrend=0.04). CONCLUSION: Heritabilities of VEGF, HGF, angiopoitein-2, sTie-2 and sFlt-1 concentrations are quantile dependent. This may explain reported interactions of genetic loci (rs10738760, rs9472159, rs833061, rs3025039, rs2280789, rs1570360, rs2010963) with metabolic syndrome, diet, recurrent miscarriage, hepatocellular carcinoma, erysipelas, diabetic retinopathy, and bevacizumab treatment in their effect on VEGF concentrations.


Assuntos
Angiopoietina-2 , Fator A de Crescimento do Endotélio Vascular , Fenótipo , Fator A de Crescimento do Endotélio Vascular/genética , Receptor 1 de Fatores de Crescimento do Endotélio Vascular
3.
Int J Obes (Lond) ; 44(10): 2101-2112, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32665611

RESUMO

BACKGROUND/OBJECTIVES: Quantile-dependent expressivity occurs when a gene's phenotypic expression depends upon whether the trait (e.g., BMI) is high or low relative to its distribution. We have previously shown that the obesity effects of a genetic risk score (GRSBMI) increased significantly with increasing quantiles of BMI. However, BMI is an inexact adiposity measure and GRSBMI explains <3% of the BMI variance. The purpose of this paper is to test BMI for quantile-dependent expressivity using a more inclusive genetic measure (h2, heritability in the narrow sense), extend the result to other adiposity measures, and demonstrate its consistency with purported gene-environment interactions. SUBJECTS/METHODS: Quantile-specific offspring-parent regression slopes (ßOP) were obtained from quantile regression for height (ht) and computed tomography (CT), dual-energy x-ray absorptiometry (DXA), anthropometric, and bioelectrical impedance (BIA) adiposity measures. Heritability was estimated by 2ßOP/(1 + rspouse) in 6227 offspring-parent pairs from the Framingham Heart Study, where rspouse is the spouse correlation. RESULTS: Compared to h2 at the 10th percentile, genetic heritability was significantly greater at the 90th population percentile for BMI (3.14-fold greater, P < 10-15), waist girth/ht (3.27-fold, P < 10-15), hip girth/ht (3.12-fold, P = 6.3 × 10-14), waist-to-hip ratio (1.75-fold, P = 0.01), sagittal diameter/ht (3.89-fold, P = 3.7 × 10-7), DXA total fat/ht2 (3.62-fold, P = 0.0002), DXA leg fat/ht2 (3.29-fold, P = 2.0 × 10-11), DXA arm fat/ht2 (4.02-fold, P = 0.001), CT-visceral fat/ht2 (3.03-fold, P = 0.002), and CT-subcutaneous fat/ht2 (3.54-fold, P = 0.0004). External validity was suggested by the phenomenon's consistency with numerous published reports. Quantile-dependent expressivity potentially explains precision medicine markers for weight gain from overfeeding or antipsychotic medications, and the modifying effects of physical activity, sleep, diet, polycystic ovary syndrome, socioeconomic status, and depression on gene-BMI relationships. CONCLUSIONS: Genetic heritabilities of anthropometric, CT, and DXA adiposity measures increase with increasing adiposity. Some gene-environment interactions may arise from analyzing subjects by characteristics that distinguish high vs. low adiposity rather than the effects of environmental stimuli on transcriptional and epigenetic processes.


Assuntos
Adiposidade/genética , Interação Gene-Ambiente , Obesidade/genética , Absorciometria de Fóton , Antropometria , Estatura , Impedância Elétrica , Humanos , Gordura Intra-Abdominal , Gordura Subcutânea , Tomografia Computadorizada por Raios X , Estados Unidos
4.
Behav Genet ; 50(5): 332-345, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32661760

RESUMO

Genetic heritability (h2) of alcohol use is reported to be greater in rural dwellers, distressed marriages, low socioeconomic status, in girls who are unmarried or lacking closeness with their parents or religious upbringing, in less-educated men, and in adolescents with peers using alcohol. However, these are all risk factors for heavy drinking, and the greater heritability could be due to quantile-dependent expressivity, i.e., h2 dependent upon whether the phenotype (alcohol intake) is high or low relative to its distribution. Quantile regression showed that h2 estimated from the offspring-parent regression slope increased significantly from lowest to highest gram/day of alcohol consumption (0.006 ± 0.001 per percent, P = 1.1 × 10-7). Heritability at the 90th percentile of the sample distribution (0.557 ± 0.116) was 4.5-fold greater than at the 10th percentile (0.122 ± 0.037). Heritabilities for intakes of other macronutrients were not quantile-dependent. Thus quantile-dependent expressivity may explain the higher estimated heritability associated with risk factors for high alcohol consumption.


Assuntos
Consumo de Bebidas Alcoólicas/genética , Padrões de Herança , Nutrientes , Adolescente , Adulto , Estudos de Coortes , Ingestão de Alimentos/genética , Feminino , Humanos , Masculino , Nutrientes/administração & dosagem , Fatores de Risco , Adulto Jovem
5.
Behav Genet ; 50(2): 119-126, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31900678

RESUMO

Estimated heritability of coffee intake ranges from 0.36 to 0.58, however, these point estimates assume that inherited effects are the same throughout the distribution of coffee intake, i.e., whether consumption is high or low relative to intake in the population. Quantile regression of 4788 child-parent pairs and 2380 siblings showed that offspring-parent and sibling concordance became progressively greater with increasing quantiles of coffee intake. Each cup/day increase in the parents' coffee intake was associated with an offspring increase of 0.020 ± 0.013 cup/day at the 10th percentile of the offsprings' coffee intake (slope ± SE, NS), 0.137 ± 0.034 cup/day at their 25th percentile (P = 5.2 × 10-5), 0.159 ± 0.029 cup/day at the 50th percentile (P = 5.8 × 10-8), 0.233 ± 0.049 cup/day at the 75th percentile (P = 1.8 × 10-6), and 0.284 ± 0.054 cup/day at the 90th percentile (P = 1.2 × 10-7). This quantile-specific heritability suggests that factors that distinguish heavier vs. lighter drinkers (smoking, male sex) will likely manifest differences in estimated heritability, as reported.


Assuntos
Café/metabolismo , Ingestão de Líquidos/genética , Família , Feminino , Interação Gene-Ambiente , Estudo de Associação Genômica Ampla , Humanos , Masculino , Modelos Estatísticos , Característica Quantitativa Herdável , Fatores de Risco , Fumantes
6.
Waste Manag Res ; 38(9): 942-965, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32705957

RESUMO

Thermogravimetric analysis (TGA) is the most widespread thermal analytical technique applied to waste materials. By way of critical review, we establish a theoretical framework for the use of TGA under non-isothermal conditions for compositional analysis of waste-derived fuels from municipal solid waste (MSW) (solid recovered fuel (SRF), or refuse-derived fuel (RDF)). Thermal behaviour of SRF/RDF is described as a complex mixture of several components at multiple levels (including an assembly of prevalent waste items, materials, and chemical compounds); and, operating conditions applied to TGA experiments of SRF/RDF are summarised. SRF/RDF mainly contains cellulose, hemicellulose, lignin, polyethylene, polypropylene, and polyethylene terephthalate. Polyvinyl chloride is also used in simulated samples, for its high chlorine content. We discuss the main limitations for TGA-based compositional analysis of SRF/RDF, due to inherently heterogeneous composition of MSW at multiple levels, overlapping degradation areas, and potential interaction effects among waste components and cross-contamination. Optimal generic TGA settings are highlighted (inert atmosphere and low heating rate (⩽10°C), sufficient temperature range for material degradation (⩾750°C), and representative amount of test portion). There is high potential to develop TGA-based composition identification and wider quality assurance and control methods using advanced thermo-analytical techniques (e.g. TGA with evolved gas analysis), coupled with statistical data analytics.


Assuntos
Resíduos de Alimentos , Eliminação de Resíduos , Incineração , Resíduos Sólidos/análise , Termogravimetria
7.
8.
Prev Med ; 121: 150-157, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30742874

RESUMO

Under "treat to risk" goals, low-density (LDL)-cholesterol follow-up measurements monitor statin compliance rather than titration to target levels, however, there is little evidence showing that more-frequent monitoring reduces LDL-cholesterol. We therefore tested whether frequency of blood tests significantly predicted lipoprotein improvements in a large anonymized clinical laboratory database. Differences (∆ ±â€¯SE) in total cholesterol, triglycerides, and LDL-cholesterol between baseline and follow-up visits were calculated for 97,548 men and 110,424 women whose physicians sent blood to Boston Heart Diagnostics for analysis between 2010 and 2017. When adjusted for age and follow-up duration, plasma concentration changes per each follow-up measurement in men and women respectively were -2.84 ±â€¯0.10 mg/dL and -3.03 ±â€¯0.10 mg/dL for total cholesterol, -3.78 ±â€¯0.30 mg/dL and -2.26 ±â€¯0.19 mg/dL for triglycerides, and -2.54 ±â€¯0.09 mg/dL and -3.06 ±â€¯0.09 mg/dL for LDL-cholesterol (all P < 10-16). Relative to baseline, significant decreases (P < 10-16) were observed for the 1st, 2nd, and 3rd follow-up measurements for total cholesterol (mean ±â€¯SE, men: -9.4 ±â€¯0.1, -11.9 ±â€¯0.2, -13.7 ±â€¯0.3; women: -8.0 ±â€¯0.1, -10.5 ±â€¯0.2, -12.6 ±â€¯0.3 mg/dL, respectively), triglycerides (men: -10.3 ±â€¯0.4, -12.8 ±â€¯0.5, -13.4 ±â€¯0.7; women: -6.4 ±â€¯0.2, -8.8 ±â€¯0.4, -10.1 ±â€¯0.5 mg/dL, respectively) and LDL-cholesterol (men: -7.8 ±â€¯0.1, -9.9 ±â€¯0.2, -11.1 ±â€¯0.2; women: -6.9 ±â€¯0.1, -9.0 ±â€¯0.2, -10.7 ±â€¯0.2 mg/dL, respectively). When adjusted for regression to the mean, 6.9%, 9.9% and 11.8% of men, and 5.7%, 9.7% and 11.5% of women, went from having an LDL-cholesterol ≥160 to <160 mg/dL for their 1st, 2nd, and 3rd follow-up measurements, respectively. We conclude that under usual physician care, total cholesterol, triglyceride, and LDL-cholesterol concentrations decreased progressively with increased physician monitoring within a large patient population.


Assuntos
LDL-Colesterol/sangue , LDL-Colesterol/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Triglicerídeos/sangue , Adulto , Idoso , Colesterol/sangue , Bases de Dados Factuais , Feminino , Seguimentos , Humanos , Masculino , Adesão à Medicação , Pessoa de Meia-Idade , Análise de Regressão , Distribuição por Sexo
9.
Lipids Health Dis ; 18(1): 83, 2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-30943980

RESUMO

BACKGROUND: Almonds have been shown to lower LDL cholesterol but there is limited information regarding their effects on the dyslipidemia characterized by increased levels of very low density lipoproteins (VLDL) and small, dense low-density lipoprotein (LDL) particles that is associated with abdominal adiposity and high carbohydrate intake. The objective of the present study was to test whether substitution of almonds for other foods attenuates carbohydrate-induced increases in small, dense LDL in individuals with increased abdominal adiposity. METHODS: This was a randomized cross-over study of three 3wk diets, separated by 2wk washouts: a higher-carbohydrate (CHO) reference diet (CHOhigh), a higher-CHO diet with isocaloric substitution of 20% kcal (E) from almonds (CHOhigh + almonds), and a lower-CHO reference diet (CHOlow) in 9 men and 15 women who were overweight or obese. The two CHOhigh diets contained 50% carbohydrate, 15% protein, 35% fat (6% saturated, 21% monounsaturated, 8% polyunsaturated), while the CHOlow diet contained 25% carbohydrate, 28% protein, 47% fat (8% saturated, 28% monounsaturated, 8% polyunsaturated). Lipoprotein subfraction concentrations were measured by ion mobility. RESULTS: Relative to the CHOlow diet: 1) the CHOhigh + almonds diet significantly increased small, dense LDLIIIa (mean difference ± SE: 28.6 ± 10.4 nmol/L, P = 0.008), and reduced LDL-peak diameter (- 1.7 ± 0.6 Å, P = 0.008); 2) the CHOhigh diet significantly increased medium-sized LDLIIb (24.8 ± 11.4 nmol/L, P = 0.04) and large VLDL (3.7 ± 1.8 nmol/L, P = 0.05). Relative to CHOlow, the effects of CHOhigh on LDLIIIa (17.7 ± 10.6 nmol/L) and LDL-peak diameter (- 1.1 ± 0.6 Å) were consistent with those of CHOhigh + almonds, and the effects of CHOhigh + almonds on LDLIIb (21.0 ± 11.2 nmol/L) and large VLDL (2.8 ± 1.8 nmol/L) were consistent with those of CHOhigh, but did not achieve statistical significance (P > 0.05). None of the variables examined showed a significant difference between the CHOhigh + almonds and CHOhigh diets (P > 0.05). CONCLUSION: Our analyses provided no evidence that deriving 20% E from almonds significantly modifies increases in levels of small, dense LDL or other plasma lipoprotein changes induced by a higher carbohydrate low saturated fat diet in individuals with increased abdominal adiposity. TRIAL REGISTRATION: Clinicaltrials.gov NCT01792648 .


Assuntos
Doenças Cardiovasculares/dietoterapia , Carboidratos da Dieta/administração & dosagem , Obesidade Abdominal/dietoterapia , Prunus dulcis , Adiposidade/efeitos dos fármacos , Adulto , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/patologia , LDL-Colesterol/sangue , Dieta com Restrição de Gorduras/métodos , Gorduras na Dieta/administração & dosagem , Ingestão de Energia/efeitos dos fármacos , Feminino , Humanos , Lipoproteínas/sangue , Lipoproteínas VLDL/sangue , Masculino , Pessoa de Meia-Idade , Caracteres Sexuais , Triglicerídeos/sangue
10.
Lipids Health Dis ; 18(1): 154, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31311555

RESUMO

BACKGROUND AND AIMS: Non-high-density (HDL)-cholesterol, low-density lipoprotein (LDL)-particle number, apolipoprotein B, lipoprotein(a) (Lp(a)), and small-dense (sdLDL) and large-buoyant (lbLDL) LDL-subfractions are emerging apo B-containing atherosclerotic cardiovascular disease (ASCVD) risk factors. Current guidelines emphasize lifestyle, including weight loss, for ASCVD risk management. Whether weight change affects these emerging risk factors beyond that predicted by traditional triglyceride and LDL-cholesterol measurements remains to be determined. METHOD: Regression analyses of fasting ∆apo B-containing lipoproteins vs. ∆BMI were examined in a large anonymized clinical laboratory database of 33,165 subjects who did not report use of lipid-lowering medications. Regression slopes (±SE) were estimated as: *∆mmol/L per ∆kg/m2, †∆g/L per ∆kg/m2, ‡∆% per ∆kg/m2, and §∆µmol/L per ∆kg/m2. RESULTS: When adjusted for age, ∆BMI was significantly related to ∆nonHDL-cholesterol (males: 0.0238 ± 0.0041, P = 7.9 × 10- 9; females: 0.0330 ± 0.0037, P < 10- 16)*, ∆LDL-particles (males: 0.0128 ± 0.0024, P = 2.1 × 10- 7; females: 0.0114 ± 0.0022, P = 3.2 × 10- 7)*, ∆apo B (males: 0.0053 ± 0.0010, P = 7.9 × 10- 8; females: 0.0073 ± 0.0009, P = 2.2 × 10- 16)†, ∆sdLDL (males: 0.0125 ± 0.0015, P = 2.2 × 10- 16; females: 0.0128 ± 0.0012, P < 10- 16)*, ∆percent LDL carried on small dense particles (%sdLDL, males: 0.296 ± 0.035, P < 10- 16; females: 0.221 ± 0.023, P < 10- 16)‡, ∆triglycerides (males: 0.0358 ± 0.0049, P = 2.0 × 10- 13; females: 0.0304 ± 0.0029, P < 10- 16)*, and ∆LDL-cholesterol (males: 0.0128 ± 0.0034, P = 0.0002; females: 0.0232 ± 0.0031, P = 1.2 × 10- 13)* in both males and females. Age-adjusted ∆BMI was significantly related to ∆lbLDL in females (0.0098 ± 0.0024, P = 3.9 × 10- 5)* but not males (0.0007 ± 0.0026, P = 0.78)*. Female showed significantly greater increases in ∆LDL-cholesterol (P = 0.02) and ∆lbLDL (P = 0.008) per ∆BMI than males. ∆BMI had a greater effect on ∆LDL-cholesterol measured directly than indirect estimate of ∆LDL-cholesterol from the Friedewald equation. When sexes were combined and adjusted for age, sex, ∆triglycerides and ∆LDL-cholesterol, ∆BMI retained residual associations with ∆nonHDL-cholesterol (0.0019 ± 0.0009, P = 0.03)*, ∆LDL-particles (0.0032 ± 0.0010, P = 0.001)*, ∆apo B (0.0010 ± 0.0003, P = 0.0008)†, ∆Lp(a) (- 0.0091 ± 0.0021, P = 1.2 × 10- 5)§, ∆sdLDL (0.0001 ± 0.0000, P = 1.6 × 10- 11)* and ∆%sdLDL (0.151 ± 0.018, P < 10- 16) ‡. CONCLUSIONS: Emerging apo B-containing risk factors show associations with weight change beyond those explained by the more traditional triglyceride and LDL-cholesterol measurements.


Assuntos
Apolipoproteína B-100/sangue , Aterosclerose/sangue , Peso Corporal , Doenças Cardiovasculares/sangue , Aterosclerose/etiologia , Índice de Massa Corporal , Doenças Cardiovasculares/etiologia , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Fatores de Risco , Triglicerídeos/sangue
11.
Cardiovasc Diabetol ; 17(1): 56, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29712560

RESUMO

BACKGROUND: Cardiovascular disease (CVD) is a leading cause of death among adults with type 2 diabetes mellitus (T2D). We recently reported that glycemic control in patients with T2D can be significantly improved through a continuous care intervention (CCI) including nutritional ketosis. The purpose of this study was to examine CVD risk factors in this cohort. METHODS: We investigated CVD risk factors in patients with T2D who participated in a 1 year open label, non-randomized, controlled study. The CCI group (n = 262) received treatment from a health coach and medical provider. A usual care (UC) group (n = 87) was independently recruited to track customary T2D progression. Circulating biomarkers of cholesterol metabolism and inflammation, blood pressure (BP), carotid intima media thickness (cIMT), multi-factorial risk scores and medication use were examined. A significance level of P < 0.0019 ensured two-tailed significance at the 5% level when Bonferroni adjusted for multiple comparisons. RESULTS: The CCI group consisted of 262 participants (baseline mean (SD): age 54 (8) year, BMI 40.4 (8.8) kg m-2). Intention-to-treat analysis (% change) revealed the following at 1-year: total LDL-particles (LDL-P) (- 4.9%, P = 0.02), small LDL-P (- 20.8%, P = 1.2 × 10-12), LDL-P size (+ 1.1%, P = 6.0 × 10-10), ApoB (- 1.6%, P = 0.37), ApoA1 (+ 9.8%, P < 10-16), ApoB/ApoA1 ratio (- 9.5%, P = 1.9 × 10-7), triglyceride/HDL-C ratio (- 29.1%, P < 10-16), large VLDL-P (- 38.9%, P = 4.2 × 10-15), and LDL-C (+ 9.9%, P = 4.9 × 10-5). Additional effects were reductions in blood pressure, high sensitivity C-reactive protein, and white blood cell count (all P < 1 × 10-7) while cIMT was unchanged. The 10-year atherosclerotic cardiovascular disease (ASCVD) risk score decreased - 11.9% (P = 4.9 × 10-5). Antihypertensive medication use was discontinued in 11.4% of CCI participants (P = 5.3 × 10-5). The UC group of 87 participants [baseline mean (SD): age 52 (10) year, BMI 36.7 (7.2) kg m-2] showed no significant changes. After adjusting for baseline differences when comparing CCI and UC groups, significant improvements for the CCI group included small LDL-P, ApoA1, triglyceride/HDL-C ratio, HDL-C, hsCRP, and LP-IR score in addition to other biomarkers that were previously reported. The CCI group showed a greater rise in LDL-C. CONCLUSIONS: A continuous care treatment including nutritional ketosis in patients with T2D improved most biomarkers of CVD risk after 1 year. The increase in LDL-cholesterol appeared limited to the large LDL subfraction. LDL particle size increased, total LDL-P and ApoB were unchanged, and inflammation and blood pressure decreased. Trial registration Clinicaltrials.gov: NCT02519309. Registered 10 August 2015.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Prestação Integrada de Cuidados de Saúde , Diabetes Mellitus Tipo 2/dietoterapia , Cetoacidose Diabética/dietoterapia , Dieta com Restrição de Carboidratos , Dieta para Diabéticos , Estado Nutricional , Ácido 3-Hidroxibutírico/sangue , Adulto , Biomarcadores/sangue , Glicemia/metabolismo , Pressão Sanguínea , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/fisiopatologia , Terapia Combinada , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/fisiopatologia , Cetoacidose Diabética/sangue , Cetoacidose Diabética/diagnóstico , Cetoacidose Diabética/fisiopatologia , Dieta com Restrição de Carboidratos/efeitos adversos , Dieta para Diabéticos/efeitos adversos , Feminino , Humanos , Hipoglicemiantes/uso terapêutico , Indiana , Mediadores da Inflamação/sangue , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
12.
Br J Nutr ; 116(12): 2020-2029, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27993177

RESUMO

Production of trimethylamine-N-oxide (TMAO), a biomarker of CVD risk, is dependent on intestinal microbiota, but little is known of dietary conditions promoting changes in gut microbial communities. Resistant starches (RS) alter the human microbiota. We sought to determine whether diets varying in RS and carbohydrate (CHO) content affect plasma TMAO levels. We also assessed postprandial glucose and insulin responses and plasma lipid changes to diets high and low in RS. In a cross-over trial, fifty-two men and women consumed a 2-week baseline diet (41 percentage of energy (%E) CHO, 40 % fat, 19 % protein), followed by 2-week high- and low-RS diets separated by 2-week washouts. RS diets were assigned at random within the context of higher (51-53 %E) v. lower CHO (39-40 %E) intake. Measurements were obtained in the fasting state and, for glucose and insulin, during a meal test matching the composition of the assigned diet. With lower CHO intake, plasma TMAO, carnitine, betaine and γ-butyrobetaine concentrations were higher after the high- v. low-RS diet (P<0·01 each). These metabolites were not differentially affected by high v. low RS when CHO intake was high. Although the high-RS meal reduced postprandial insulin and glucose responses when CHO intake was low (P<0·01 each), RS did not affect fasting lipids, lipoproteins, glucose or insulin irrespective of dietary CHO content. In conclusion, a lower-CHO diet high in RS was associated with higher plasma TMAO levels. These findings, together with the absence of change in fasting lipids, suggest that short-term high-RS diets do not improve markers of cardiometabolic health.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Dieta com Restrição de Carboidratos , Disbiose/dietoterapia , Metilaminas/agonistas , Amido/uso terapêutico , Adulto , Biomarcadores/sangue , Índice de Massa Corporal , California/epidemiologia , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/microbiologia , Estudos Cross-Over , Dieta da Carga de Carboidratos/efeitos adversos , Disbiose/etiologia , Disbiose/metabolismo , Disbiose/fisiopatologia , Feminino , Microbioma Gastrointestinal , Humanos , Hiperglicemia/prevenção & controle , Hiperinsulinismo/prevenção & controle , Resistência à Insulina , Masculino , Metilaminas/sangue , Metilaminas/metabolismo , Pessoa de Meia-Idade , Obesidade/microbiologia , Obesidade/fisiopatologia , Sobrepeso/microbiologia , Sobrepeso/fisiopatologia , Risco , Amido/efeitos adversos , Amido/metabolismo
13.
Int J Cancer ; 135(5): 1195-202, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-24470442

RESUMO

The purpose of these analyses is to test prospectively whether post-diagnosis running and walking differ significantly in their association with breast cancer mortality. Cox proportional hazard analyses were used to compare breast cancer mortality to baseline exercise energy expenditure (METs, 1 MET-hour ≅1 km run) in 272 runners and 714 walkers previously diagnosed with breast cancer from the National Runners' and Walkers' Health Studies when adjusted for age, race, menopause, family history, breastfeeding and oral contraceptive use. Diagnosis occurred (mean ± SD) 7.9 ± 7.3 years before baseline. Forty-six women (13 runners and 33 walkers) died from breast cancer during 9.1-year mortality surveillance. For the 986 runners and walkers combined, breast cancer mortality decreased an average of 23.9% MET-hours/day [95% confidence interval (CI): 7.9-38.3%; p = 0.004]. There was a significantly greater decrease in risk for running than walking (risk per MET-hours/day run vs. walked: p = 0.03). For the 272 runners analyzed separately, breast cancer mortality decreased an average of 40.9% per MET-hours/day run (95% CI: 19.3-60.0%, p = 0.0004). When analyzed by categories of running energy expenditure, breast cancer mortality was 87.4% lower for the 1.8-3.6 MET-hours/day category (95% CI: 41.3-98.2% lower, p = 0.008) and 95.4% lower for the ≥3.6 MET-hours/day category (95% CI: 71.9-100% lower, p = 0.0004) compared to the <1.07 MET-hours/day category. In contrast, the 714 walkers showed a nonsignificant 4.6% decrease in breast cancer mortality per MET-hours/day walked (95% CI: 27.3% decreased risk to 21.3% increased risk, p = 0.71). These results suggest that post-diagnosis running is associated with significantly lower breast cancer mortality than post-diagnosis walking.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/mortalidade , Corrida/fisiologia , Caminhada/fisiologia , Metabolismo Energético , Feminino , Humanos , Pessoa de Meia-Idade , Esforço Físico , Estudos Prospectivos
14.
J Nutr ; 144(11): 1753-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25332473

RESUMO

BACKGROUND: Previous human studies reported inconsistent effects of dietary protein and branched-chain amino acids (BCAAs) on insulin action and glucose metabolism. Similarly, it is unclear whether saturated fat (SF) intake influences these metabolic variables. OBJECTIVE: The objective of this study was to test the effects of high [30% of energy (%E)] vs. moderate (20%E) intakes of protein (primarily whey) on insulin action and lipid and lipoprotein concentrations in the context of both high (15%E) and low (7%E) SF diets. METHODS: The study was conducted as a randomized controlled trial in 158 overweight and obese men and women. After a 4-wk baseline diet [55%E carbohydrate, 15%E protein, 30%E fat (7%E SF)], participants were randomly assigned to 4 wk of either the baseline diet or 1 of 4 test diets containing 35%E carbohydrate and either 20%E or 30%E protein and either 7%E or 15%E SF. Frequently sampled i.v. glucose tolerance tests were administered after each dietary period. RESULTS: Other than significantly higher fasting glucose concentrations for high vs. moderate protein intakes with a low-fat diet (difference ± SE: 0.47 ± 0.14 mmol/L; P = 0.001), there were no significant effects of dietary protein or SF on glucose metabolism, plasma insulin, or concentrations of lipids and lipoproteins. Changes in plasma BCAAs across all diets were negatively correlated with changes in the metabolic clearance rate of insulin (ρ = -0.18, P = 0.03) and positively correlated with changes in the acute insulin response to glucose (ρ = 0.15, P = 0.05). CONCLUSIONS: These findings suggest that short-term intake of BCAAs can influence insulin dynamics. However, in this group of overweight and obese individuals, neither high protein nor SF intake affected insulin sensitivity or plasma concentrations of lipids and lipoproteins. This trial was registered at clinicaltrials.gov as NCT00508937.


Assuntos
Gorduras na Dieta/farmacologia , Proteínas Alimentares/farmacologia , Resistência à Insulina , Lipídeos/sangue , Lipoproteínas/sangue , Sobrepeso/sangue , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sobrepeso/metabolismo
15.
Arterioscler Thromb Vasc Biol ; 33(5): 1085-91, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23559628

RESUMO

OBJECTIVE: To test whether equivalent energy expenditure by moderate-intensity (eg, walking) and vigorous-intensity exercise (eg, running) provides equivalent health benefits. APPROACH AND RESULTS: We used the National Runners' (n=33 060) and Walkers' (n=15 945) Health Study cohorts to examine the effect of differences in exercise mode and thereby exercise intensity on coronary heart disease (CHD) risk factors. Baseline expenditure (metabolic equivant hours per day [METh/d]) was compared with self-reported, physician-diagnosed incident hypertension, hypercholesterolemia, diabetes mellitus, and CHD during 6.2 years follow-up. Running significantly decreased the risks for incident hypertension by 4.2% (P<10(-7)), hypercholesterolemia by 4.3% (P<10(-14)), diabetes mellitus by 12.1% (P<10(-5)), and CHD by 4.5% per METh/d (P=0.05). The corresponding reductions for walking were 7.2% (P<10(-6)), 7.0% (P<10(-8)), 12.3% (P<10(-4)), and 9.3% (P=0.01). Relative to <1.8 METh/d, the risk reductions for 1.8 to 3.6, 3.6 to 5.4, 5.4 to 7.2, and ≥7.2 METh/d were as follows: (1) 10.1%, 17.7%, 25.1%, and 34.9% from running and 14.0%, 23.8%, 21.8%, and 38.3% from walking for hypercholesterolemia; (2) 19.7%, 19.4%, 26.8%, and 39.8% from running and 14.7%, 19.1%, 23.6%, and 13.3% from walking for hypertension; and (3) 43.5%, 44.1%, 47.7%, and 68.2% from running, and 34.1%, 44.2% and 23.6% from walking for diabetes mellitus (walking >5.4 METh/d excluded for too few cases). The risk reductions were not significantly different for running than walking for diabetes mellitus (P=0.94), hypertension (P=0.06), or CHD (P=0.26), and only marginally greater for walking than running for hypercholesterolemia (P=0.04). CONCLUSIONS: Equivalent energy expenditures by moderate (walking) and vigorous (running) exercise produced similar risk reductions for hypertension, hypercholesterolemia, diabetes mellitus, and possibly CHD.


Assuntos
Colesterol/sangue , Diabetes Mellitus/prevenção & controle , Hipertensão/prevenção & controle , Comportamento de Redução do Risco , Corrida , Caminhada , Adulto , Idoso , Estudos de Coortes , Doença das Coronárias/prevenção & controle , Metabolismo Energético , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
16.
Environ Sci Technol ; 48(1): 819-26, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24283272

RESUMO

Producing both hydrogen and high-value carbon nanotubes (CNTs) derived from waste plastics is reported here using a pyrolysis-reforming technology comprising a two-stage reaction system, in the presence of steam and a Ni-Mn-Al catalyst. The waste plastics consisted of plastics from a motor oil container (MOC), commercial waste high density polyethylene (HDPE) and regranulated HDPE waste containing polyvinyl chloride (PVC). The results show that hydrogen can be produced from the pyrolysis-reforming process, but also carbon nanotubes are formed on the catalyst. However, the content of 0.3 wt.% polyvinyl chloride in the waste HDPE (HDPE/PVC) has been shown to poison the catalyst and significantly reduce the quantity and purity of CNTs. The presence of sulfur has shown less influence on the production of CNTs in terms of quantity and CNT morphologies. Around 94.4 mmol H2 g(-1) plastic was obtained for the pyrolysis-reforming of HDPE waste in the presence of the Ni-Mn-Al catalyst and steam at a reforming temperature of 800 °C. The addition of steam in the process results in an increase of hydrogen production and reduction of carbon yield; in addition, the defects of CNTs, for example, edge dislocations were found to be increased with the introduction of steam (from Raman analysis).


Assuntos
Hidrogênio/química , Nanotubos de Carbono/química , Plásticos/análise , Eliminação de Resíduos/métodos , Temperatura , Carbono/análise , Catálise , Nanotubos de Carbono/ultraestrutura , Oxirredução , Polietileno/análise , Análise Espectral Raman , Resíduos/análise , Difração de Raios X
17.
J Acoust Soc Am ; 135(5): 2727-37, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24815256

RESUMO

Splitter silencers are found in ventilation and gas turbine systems and consist of parallel baffles of porous material placed within a duct so that they split the mean gas flow. Theoretical investigations into dissipative splitter silencers have generally been limited to two dimensions and this limits the analysis to finding the silencer eigenmodes or, for a finite length silencer, to rectangular baffles only. In this article a numerical point collocation approach is used to extend theoretical predictions to three dimensions. This facilitates the analysis of more complex silencer designs such as "bar" silencers and theoretical predictions are validated by comparison with experimental measurements. The insertion loss of different silencer designs is evaluated and the performance of a bar silencer is compared to traditional designs for rectangular and circular ducts. It is shown that a bar silencer with a volume of material identical to an equivalent parallel baffle design delivers a significant improvement in insertion loss at higher frequencies, although this is at the expense of a small reduction in performance at low frequencies. It is also shown that under most circumstances it is possible to get good agreement between prediction and experiment even for relatively large Helmholtz numbers.

18.
J Environ Manage ; 146: 189-197, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25173727

RESUMO

Biochar has potential to sequester carbon in soils and simultaneously improve soil quality and plant growth. More understanding of biochar variation is needed to optimise these potential benefits. Slow pyrolysis at 600 °C was undertaken to determine how yields and characteristics of biochars differ when produced from eight different agricultural residues. Biochar properties such as carbon content, surface area, pH, ultimate and proximate analysis, nutrient and metal content and the R50 recalcitrance index were determined. Significant variations seen in biochar characteristics were attributed to feedstock variation since pyrolysis conditions were constant. Biochar yields varied from 28% to 39%. Average carbon content was 51%. Ash content of both feedstocks and biochars were correlated with biochar carbon content. Macronutrients were concentrated during pyrolysis, but biochar macronutrient content was low in comparison to biochars produced from more nutrient rich feedstocks. Most biochars were slightly alkaline, ranging from pH 6.1 to pH 11.6. pH was correlated with biochar K content. Aromaticity was increased with pyrolysis, shown by a reduction in biochar H/C and O/C ratios relative to feedstock values. The R50 recalcitrance index showed biochars to be either class 2 or class 3. Biochar carbon sequestration potential was 21.3%-32.5%. The R50 recalcitrance index is influenced by the presence of alkali metals in the biochar which may lead to an under-estimation of biochar stability. The residues assessed here, at current global availability, could produce 373 Mt of biochar. This quantity of biochar has the potential to sequester 0.55 Pg CO2 yr(-1) in soils over long time periods.


Assuntos
Sequestro de Carbono , Carvão Vegetal/química , Solo/química , Produtos Agrícolas , Humanos , Temperatura
19.
Environ Technol ; 35(13-16): 1823-30, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24956775

RESUMO

Three environmental samples containing dioxins and furans have been oxidized in the presence of hydrogen peroxide under supercritical water oxidation conditions. The samples consisted of a waste incinerator fly ash, sewage sludge and contaminated industrial soil. The reactor system was a batch, autoclave reactor operated at temperatures between 350 degrees C and 450degrees C, corresponding to pressures of approximately 20-33.5 MPa and with hydrogen peroxide concentrations from 0.0 to 11.25 vol%. Hydrogen peroxide concentration and temperature/pressure had a strong positive effect on the oxidation of dioxins and furans. At the highest temperatures and pressure of supercritical water oxidation of 4500C and 33.5 MPa and with 11.25 vol% of hydrogen peroxide, the destruction efficiencies of the individual polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDD/PCDF) isomers were between 90% and 99%. There did not appear to be any significant differences in the PCDD/PCDF destruction efficiencies in relation to the different sample matrices of the waste incinerator fly ash, sewage sludge and contaminated industrial soil.


Assuntos
Dioxinas/química , Poluentes Ambientais/química , Furanos/química , Cinza de Carvão/química , Resíduos Industriais , Oxirredução , Esgotos/química , Solo/química
20.
Chemosphere ; 359: 142294, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38734247

RESUMO

Development of efficient catalysts for non-thermal plasma (NTP) assisted catalysis to mitigate the formation of harmful by-products is a significant challenge in the degradation of chlorinated volatile organic compounds (Cl-VOCs). In this study, catalytically active Pt nanoparticles supported on non-porous SiO2 and silicalite-1 zeolites (S1) with different pore structure were comparatively investigated for catalytic chlorobenzene degradation under NTP condition. It was shown that the pore structure could significantly impact the metal size and metal dispersion rate. Pt supported on modified S1 hierarchical meso-micro-porous silicalite-1 (Pt/D-S1) exhibited the smallest particle size (∼6.19 nm) and the highest dispersion rate (∼1.87). Additionally, Pt/D-S1 demonstrated superior catalytic performance compared to the other catalysts, achieving the highest chlorobenzene conversion and COx selectivity at about 80% and 75%, respectively. Furthermore, the pore structure also affected the formation of by-products according to the findings from GC-MS analysis. Pt/SiO2 generated a total of 18 different species of organic compounds, whereas only 12 species of organic by-products were identified in the Pt/D-S1 system (e.g. polychlorinated compounds like 3,4 dichlorophenol were exclusively identified in Pt/SiO2). Moreover, dioxin-like polychlorinated biphenyl and other chlorinated organic compounds, which have potential to form highly toxic dioxins, were detected in the catalysts. HRGC-HRMS confirmed and quantified the 17 different dioxin/furans formed on Pt/SiO2 (25,100 ng TEQ kg-1), Pt/S1 (515 ng TEQ kg-1) and Pt/D-S1 (367 ng TEQ kg-1). The correlation between synthesis-structure-performance in this study provides insights into the design of catalysts for deep oxidation of Cl-VOCs in NTP system.


Assuntos
Clorobenzenos , Platina , Dibenzodioxinas Policloradas , Dióxido de Silício , Clorobenzenos/química , Catálise , Platina/química , Dióxido de Silício/química , Dibenzodioxinas Policloradas/química , Gases em Plasma/química , Zeolitas/química , Compostos Orgânicos Voláteis/química , Nanopartículas Metálicas/química , Benzofuranos/química
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