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1.
Small ; 20(5): e2305533, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37786306

RESUMEN

CO2 capture and conversion technology are highly promising technologies that definitely play a part in the journey towards carbon neutrality. Releasing CO2 by mild stimulation and the development of high efficiency catalytic processes are urgently needed. The magnetic field, as a thermodynamic parameter independent of temperature and pressure, is vital in the enhancement of CO2 capture and conversion process. In this review, the recent progress of magnetic field-enhanced CO2 capture and conversion is comprehensively summarized. The theoretical fundamentals of magnetic field on CO2 adsorption, release and catalytic reduction process are discussed, including the magnetothermal, magnetohydrodynamic, spin selection, Lorentz forces, magnetoresistance and spin relaxation effects. Additionally, a thorough review of the current progress of the enhancement strategies of magnetic field coupled with a variety of fields (including thermal, electricity, and light) is summarized in the aspect of CO2 related process. Finally, the challenges and prospects associated with the utilization of magnetic field-assisted techniques in the construction of CO2 capture and conversion systems are proposed. This review offers a reference value for the future design of catalysts, mechanistic investigations, and practical implementation for magnetic field enhanced CO2 capture and conversion.

2.
J Magn Reson Imaging ; 58(4): 1258-1267, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-36747321

RESUMEN

BACKGROUND: Abdominal aortic aneurysms (AAAs) may rupture before reaching maximum diameter (Dmax ) thresholds for repair. Aortic wall microvasculature has been associated with elastin content and rupture sites in specimens, but its relation to progression is unknown. PURPOSE: To investigate whether dynamic contrast-enhanced (DCE) MRI of AAA is associated with Dmax or growth. STUDY TYPE: Prospective. POPULATION: A total of 27 male patients with infrarenal AAA (mean age ± standard deviation = 75 ± 5 years) under surveillance with DCE MRI and 2 years of prior follow-up intervals with computed tomography (CT) or MRI. FIELD STRENGTH/SEQUENCE: A 3-T, dynamic three-dimensional (3D) fast gradient-echo stack-of-stars volumetric interpolated breath-hold examination (Star-VIBE). ASSESSMENT: Wall voxels were manually segmented in two consecutive slices at the level of Dmax . We measured slope to 1-minute and area under the curve (AUC) to 1 minute and 4 minutes of the signal intensity change postcontrast relative to that precontrast arrival, and, Ktrans , a measure of microvascular permeability, using the Patlak model. These were averaged over all wall voxels for association to Dmax and growth rate, and, over left/right and anterior/posterior quadrants for testing circumferential homogeneity. Dmax was measured orthogonal to the aortic centerline and growth rate was calculated by linear fit of Dmax measurements. STATISTICAL TESTS: Pearson correlation and linear mixed effects models. A P value <0.05 was considered statistically significant. RESULTS: In 44 DCE MRIs, mean Dmax was 45 ± 7 mm and growth rate in 1.5 ± 0.4 years of prior follow-up was 1.7 ± 1.2 mm per year. DCE measurements correlated with each other (Pearson r = 0.39-0.99) and significantly differed between anterior/posterior versus left/right quadrants. DCE measurements were not significantly associated with Dmax (P = 0.084, 0.289, 0.054 and 0.255 for slope, AUC at 1 minute and 4 minutes, and Ktrans , respectively). Slope and 4 minutes AUC significantly associated with growth rate after controlling for Dmax . CONCLUSION: Contrast uptake may be increased in lateral aspects of the AAA. Contrast enhancement 1-minute slope and 4-minutes AUC may be associated with a period of recent AAA growth that is independent of Dmax . EVIDENCE LEVEL: 3. TECHNICAL EFFICACY: Stage 2.


Asunto(s)
Aneurisma de la Aorta Abdominal , Humanos , Masculino , Estudios Prospectivos , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/complicaciones , Aorta , Progresión de la Enfermedad , Imagen por Resonancia Magnética/métodos
3.
Phys Chem Chem Phys ; 25(11): 8064-8073, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36876717

RESUMEN

The purification of carbon monoxide in H2-rich streams is an urgent problem for the practical application of fuel cells, and requires the development of efficient and economical catalysts for the preferential oxidation of CO (CO-PROX). In the present work, a facile solid phase synthesis method followed by an impregnation method were adopted to prepare a ternary CuCoMnOx spinel oxide, which shows superior catalytic performance with CO conversion of 90% for photothermal CO-PROX at 250 mW cm-2. The dopant of copper species leads to the incorporation of Cu ions into the CoMnOx spinel lattice forming a ternary CuCoMnOx spinel oxide. The appropriate calcination temperature (300 °C) contributes to the generation of abundant oxygen vacancies and strong synergetic Cu-Co-Mn interactions, which are conducive to the mobility of oxygen species to participate in CO oxidation reactions. On the other hand, the highest photocurrent response of CuCoMnOx-300 also promotes the photo-oxidation activity of CO due to the high carrier concentration and efficient carrier separation. In addition, the in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) confirmed that doping copper species could enhance the CO adsorption capacity of the catalyst due to the generation of Cu+ species, which significantly increased the CO oxidation activity of the CuCoMnOx spinel oxide. The present work provides a promising and eco-friendly solution to remove the trace CO in H2-rich gas over CuCoMnOx ternary spinel oxide with solar light as the only energy source.

4.
Pain Med ; 24(6): 644-651, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36331329

RESUMEN

OBJECTIVE: Depression frequently coexists with chronic pain. Contemporary models suggest that these conditions share pathobiological mechanisms, prompting a need to investigate their temporal association. This investigation aimed to explore two distinctly different chronic pain conditions, and their cross-sectional and prospective associations with depression. METHODS: Self-reported information was available on chronic widespread pain (CWP), chronic low back pain (CLBP) (45 years), and depression symptoms (45 and 50 years) from up to 9,377 participants in the 1958 British cohort. Depression symptom outcomes were derived by "Clinical Interview Schedule-Revised" (45 years) and "Short Form-36" (50 years). Relationships between both chronic pain conditions and depression symptoms were investigated by fitting four separate logistic regression models, each with varying levels of covariate adjustment, including depression at baseline. RESULTS: CWP was associated with depression symptoms cross-sectionally (odds ratio [OR] = 2.04, 95% confidence interval [CI] 1.65, 2.52; P < 0.001, n = 7,629), and prospectively when fully adjusted for baseline, sociodemographic, lifestyle, and health covariates (OR = 1.45, 95% CI 1.17, 1.80; P = < 0.001, n = 6,275). CLBP was associated with depression symptoms prospectively (full model: OR = 1.28, 95% CI 1.01, 1.61; P = 0.04, n = 6,288). In fully adjusted models the prospective association of CWP with depression symptoms was more heavily influenced by our covariates than CLBP with depression symptoms. CONCLUSION: Pain may be a stressor from which depression can arise. Development of depression may be differentially dependant upon the type of pain experienced. Screening for depression symptoms among individuals with both chronic pain conditions is indicated and should be repeated over time.


Asunto(s)
Dolor Crónico , Dolor de la Región Lumbar , Humanos , Dolor Crónico/epidemiología , Dolor de la Región Lumbar/epidemiología , Depresión/epidemiología , Estudios Transversales , Enfermedad Crónica
5.
Ann Intern Med ; 175(11): 1552-1559, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36279545

RESUMEN

BACKGROUND: Low vitamin D status is associated with increased mortality, but randomized trials on severely deficient participants are lacking. OBJECTIVE: To assess genetic evidence for the causal role of low vitamin D status in mortality. DESIGN: Nonlinear Mendelian randomization analyses. SETTING: UK Biobank, a large-scale, prospective cohort from England, Scotland, and Wales with participants recruited between March 2006 and July 2010. PARTICIPANTS: 307 601 unrelated UK Biobank participants of White European ancestry (aged 37 to 73 years at recruitment) with available measurements of 25-hydroxyvitamin D (25-(OH)D) and genetic data. MEASUREMENTS: Genetically predicted 25-(OH)D was estimated using 35 confirmed variants of 25-(OH)D. All-cause and cause-specific mortality (cardiovascular disease [CVD], cancer, and respiratory) were recorded up to June 2020. RESULTS: There were 18 700 deaths during the 14 years of follow-up. The association of genetically predicted 25-(OH)D with all-cause mortality was L-shaped (P for nonlinearity < 0.001), and risk for death decreased steeply with increasing concentrations until 50 nmol/L. Evidence for an association was also seen in analyses of mortality from cancer, CVD, and respiratory diseases (P ≤ 0.033 for all outcomes). Odds of all-cause mortality in the genetic analysis were estimated to increase by 25% (odds ratio, 1.25 [95% CI, 1.16 to 1.35]) for participants with a measured 25-(OH)D concentration of 25 nmol/L compared with 50 nmol/L. LIMITATIONS: Analyses were restricted to a White European population. A genetic approach is best suited to providing proof of principle on causality, whereas the strength of the association is approximate. CONCLUSION: Our study supports a causal relationship between vitamin D deficiency and mortality. Additional research needs to identify strategies that meet the National Academy of Medicine's guideline of greater than 50 nmol/L and that reduce the premature risk for death associated with low vitamin D levels. PRIMARY FUNDING SOURCE: National Health and Medical Research Council.


Asunto(s)
Enfermedades Cardiovasculares , Neoplasias , Deficiencia de Vitamina D , Humanos , Análisis de la Aleatorización Mendeliana , Estudios Prospectivos , Bancos de Muestras Biológicas , Deficiencia de Vitamina D/genética , Vitamina D , Enfermedades Cardiovasculares/epidemiología , Neoplasias/genética , Reino Unido/epidemiología , Factores de Riesgo
6.
Eur Heart J ; 43(18): 1731-1739, 2022 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-34891159

RESUMEN

AIMS: Low vitamin D status is associated with a higher risk for cardiovascular diseases (CVDs). Although most existing linear Mendelian randomization (MR) studies reported a null effect of vitamin D on CVD risk, a non-linear effect cannot be excluded. Our aim was to apply the non-linear MR design to investigate the association of serum 25-hydroxyvitamin D [25(OH)D] concentration with CVD risk. METHODS AND RESULTS: The non-linear MR analysis was conducted in the UK Biobank with 44 519 CVD cases and 251 269 controls. Blood pressure (BP) and cardiac-imaging-derived phenotypes were included as secondary outcomes. Serum 25(OH)D concentration was instrumented using 35 confirmed genome-wide significant variants.We also estimated the potential reduction in CVD incidence attributable to correction of low vitamin D status. There was a L-shaped association between genetically predicted serum 25(OH)D and CVD risk (Pnon-linear = 0.007), where CVD risk initially decreased steeply with increasing concentrations and levelled off at around 50 nmol/L. A similar association was seen for systolic (Pnon-linear = 0.03) and diastolic (Pnon-linear = 0.07) BP. No evidence of association was seen for cardiac-imaging phenotypes (P = 0.05 for all). Correction of serum 25(OH)D level below 50 nmol/L was predicted to result in a 4.4% reduction in CVD incidence (95% confidence interval: 1.8- 7.3%). CONCLUSION: Vitamin D deficiency can increase the risk of CVD. Burden of CVD could be reduced by population-wide correction of low vitamin D status.


Asunto(s)
Enfermedades Cardiovasculares , Deficiencia de Vitamina D , Enfermedades Cardiovasculares/complicaciones , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/genética , Humanos , Análisis de la Aleatorización Mendeliana , Polimorfismo de Nucleótido Simple/genética , Factores de Riesgo , Vitamina D , Deficiencia de Vitamina D/complicaciones , Deficiencia de Vitamina D/epidemiología , Deficiencia de Vitamina D/genética , Vitaminas
7.
Nutr Neurosci ; 25(10): 2111-2122, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34165394

RESUMEN

BACKGROUND: Coffee is a highly popular beverage worldwide, containing caffeine which is a central nervous system stimulant. OBJECTIVES: We examined whether habitual coffee consumption is associated with differences in brain volumes or the odds of dementia or stroke. METHODS: We conducted prospective analyses of habitual coffee consumption on 398,646 UK Biobank participants (age 37-73 years), including 17,702 participants with MRI information. We examined the associations with brain volume using covariate adjusted linear regression, and with odds of dementia (4,333 incident cases) and stroke (6,181 incident cases) using logistic regression. RESULTS: There were inverse linear associations between habitual coffee consumption and total brain (fully adjusted ß per cup -1.42, 95% CI -1.89, -0.94), grey matter (ß -0.91, 95% CI -1.20, -0.62), white matter (ß -0.51, 95% CI -0.83, -0.19) and hippocampal volumes (ß -0.01, 95% CI -0.02, -0.003), but no evidence to support an association with white matter hyperintensity (WMH) volume (ß -0.01, 95% CI -0.07, 0.05). The association between coffee consumption and dementia was non-linear (Pnon-linearity = 0.0001), with evidence for higher odds for non-coffee and decaffeinated coffee drinkers and those drinking >6 cups/day, compared to light coffee drinkers. After full covariate adjustment, consumption of >6 cups/day was associated with 53% higher odds of dementia compared to consumption of 1-2 cups/day (fully adjusted OR 1.53, 95% CI 1.28, 1.83), with less evidence for an association with stroke (OR 1.17, 95% CI 1.00, 1.37, p = 0.055). CONCLUSION: High coffee consumption was associated with smaller total brain volumes and increased odds of dementia.


Asunto(s)
Estimulantes del Sistema Nervioso Central , Demencia , Accidente Cerebrovascular , Adulto , Anciano , Encéfalo/diagnóstico por imagen , Cafeína/efectos adversos , Demencia/epidemiología , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Accidente Cerebrovascular/epidemiología
8.
Int J Obes (Lond) ; 45(8): 1751-1762, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34024907

RESUMEN

BACKGROUND: High milk intake has been associated with cardio-metabolic risk. We conducted a Mendelian Randomization (MR) study to obtain evidence for the causal relationship between milk consumption and cardio-metabolic traits using the lactase persistence (LCT-13910 C > T, rs4988235) variant as an instrumental variable. METHODS: We tested the association of LCT genotype with milk consumption (for validation) and with cardio-metabolic traits (for a possible causal association) in a meta-analysis of the data from three large-scale population-based studies (1958 British Birth Cohort, Health and Retirement study, and UK Biobank) with up to 417,236 participants and using summary statistics from consortia meta-analyses on intermediate traits (N = 123,665-697,307) and extended to cover disease endpoints (N = 86,995-149,821). RESULTS: In the UK Biobank, carriers of 'T' allele of LCT variant were more likely to consume milk (P = 7.02 × 10-14). In meta-analysis including UK Biobank, the 1958BC, the HRS, and consortia-based studies, under an additive model, 'T' allele was associated with higher body mass index (BMI) (Pmeta-analysis = 4.68 × 10-12) and lower total cholesterol (TC) (P = 2.40 × 10-36), low-density lipoprotein cholesterol (LDL-C) (P = 2.08 × 10-26) and high-density lipoprotein cholesterol (HDL-C) (P = 9.40 × 10-13). In consortia meta-analyses, 'T' allele was associated with a lower risk of coronary artery disease (OR:0.86, 95% CI:0.75-0.99) but not with type 2 diabetes (OR:1.06, 95% CI:0.97-1.16). Furthermore, the two-sample MR analysis showed a causal association between genetically instrumented milk intake and higher BMI (P = 3.60 × 10-5) and body fat (total body fat, leg fat, arm fat and trunk fat; P < 1.37 × 10-6) and lower LDL-C (P = 3.60 × 10-6), TC (P = 1.90 × 10-6) and HDL-C (P = 3.00 × 10-5). CONCLUSIONS: Our large-scale MR study provides genetic evidence for the association of milk consumption with higher BMI but lower serum cholesterol levels. These data suggest no need to limit milk intakes with respect to cardiovascular disease risk, with the suggested benefits requiring confirmation in further studies.


Asunto(s)
Factores de Riesgo Cardiometabólico , Dieta/estadística & datos numéricos , Síndrome Metabólico/epidemiología , Leche/estadística & datos numéricos , Animales , Cohorte de Nacimiento , Femenino , Humanos , Masculino , Análisis de la Aleatorización Mendeliana , Reino Unido
9.
Cell Mol Neurobiol ; 41(1): 115-127, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32279133

RESUMEN

Neuroinflammation is caused by excessive activation of microglia and plays an essential role in neurodegenerative diseases. After activation, microglia produce several kinds of inflammatory mediators, trigger an excessive inflammatory response, and ultimately destroy the surrounding neurons. Therefore, agents that inhibit neuroinflammation may be potential drug candidates for neurodegenerative diseases. Evodiamine (EV) has anti-inflammatory functions in peripheral tissues. However, whether EV exerts the same function in neuroinflammation is not known. In the present study, the aim was to explore whether EV attenuates microglial overactivation and therefore suppresses the development of neuroinflammation in lipopolysaccharide (LPS)-stimulated BV-2 cells. It was found that EV effectively inhibited expression of proinflammatory mediators (cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α)) via AKT/Nrf2/HO-1 activation and suppressed NF-κB p65 phosphorylation. In addition, EV could suppress LPS-induced inflammatory response and loss of dopaminergic neuron in mouse mesencephalic neuron--glia cells. Hence, these findings demonstrate that EV suppresses neuroinflammation caused by overactivated microglia via regulating the AKT/Nrf2/HO-1/NF-κB signaling axis.


Asunto(s)
Hemo-Oxigenasa 1/metabolismo , Inflamación/patología , Factor 2 Relacionado con NF-E2/metabolismo , FN-kappa B/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Quinazolinas/farmacología , Transducción de Señal , Animales , Línea Celular , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Supervivencia Celular/efectos de los fármacos , Mediadores de Inflamación/metabolismo , Lipopolisacáridos , Ratones , Modelos Biológicos , Neuroglía/metabolismo , Neuronas/metabolismo , Fosforilación/efectos de los fármacos , Transporte de Proteínas/efectos de los fármacos , Quinazolinas/química , Transducción de Señal/efectos de los fármacos , Tirosina 3-Monooxigenasa/metabolismo , Regulación hacia Arriba/efectos de los fármacos
10.
Mol Psychiatry ; 25(7): 1469-1476, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31427754

RESUMEN

Depression affects all aspects of an individual's life but evidence relating to the causal effects on health is limited. We used information from 337,536 UK Biobank participants and performed hypothesis-free phenome-wide association analyses between major depressive disorder (MDD) genetic risk score (GRS) and 925 disease outcomes. GRS-disease outcome associations passing the multiple-testing corrected significance threshold (P < 1.9 × 10-3) were followed by Mendelian randomisation (MR) analyses to test for causality. MDD GRS was associated with 22 distinct diseases in the phenome-wide discovery stage, with the strongest signal observed for MDD diagnosis and related co-morbidities including anxiety and sleep disorders. In inverse-variance weighted MR analyses, MDD was associated with several inflammatory and haemorrhagic gastrointestinal diseases, including oesophagitis (OR 1.32, 95% CI 1.18-1.48), non-infectious gastroenteritis (OR 1.25, 95% CI 1.06-1.48), gastrointestinal haemorrhage (OR 1.26, 95% CI 1.11-1.43) and intestinal E.coli infections (OR 3.24, 95% CI 1.74-6.02). Signals were also observed for symptoms/disorders of the urinary system (OR 1.36, 95% CI 1.19-1.56), asthma (OR 1.23, 95% CI 1.06-1.44), and painful respiration (OR 1.28, 95% CI 1.14-1.44). MDD was associated with disorders of lipid metabolism (OR 1.22, 95% CI 1.12-1.34) and ischaemic heart disease (OR 1.30, 95% CI 1.15-1.47). Sensitivity analyses excluding pleiotropic variants provided consistent associations. Our study indicates a causal link between MDD and a broad range of diseases, suggesting a notable burden of co-morbidity. Early detection and management of MDD is important, and treatment strategies should be selected to also minimise the risk of related co-morbidities.


Asunto(s)
Bases de Datos Factuales , Trastorno Depresivo Mayor/diagnóstico , Trastorno Depresivo Mayor/psicología , Análisis de la Aleatorización Mendeliana , Fenotipo , Adulto , Anciano , Trastorno Depresivo Mayor/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reino Unido
11.
Nutr J ; 20(1): 71, 2021 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-34315477

RESUMEN

CONTEXT: Multiple observational studies have reported an inverse relationship between 25-hydroxyvitamin D concentrations (25(OH)D) and type 2 diabetes (T2D). However, the results of short- and long-term interventional trials concerning the relationship between 25(OH)D and T2D risk have been inconsistent. OBJECTIVES AND METHODS: To evaluate the causal role of reduced blood 25(OH)D in T2D, here we have performed a bidirectional Mendelian randomization study using 59,890 individuals (5,862 T2D cases and 54,028 controls) from European and Asian Indian ancestries. We used six known SNPs, including three T2D SNPs and three vitamin D pathway SNPs, as a genetic instrument to evaluate the causality and direction of the association between T2D and circulating 25(OH)D concentration. RESULTS: Results of the combined meta-analysis of eight participating studies showed that a composite score of three T2D SNPs would significantly increase T2D risk by an odds ratio (OR) of 1.24, p = 1.82 × 10-32; Z score 11.86, which, however, had no significant association with 25(OH)D status (Beta -0.02nmol/L ± SE 0.01nmol/L; p = 0.83; Z score -0.21). Likewise, the genetically instrumented composite score of 25(OH)D lowering alleles significantly decreased 25(OH)D concentrations (-2.1nmol/L ± SE 0.1nmol/L, p = 7.92 × 10-78; Z score -18.68) but was not associated with increased risk for T2D (OR 1.00, p = 0.12; Z score 1.54). However, using 25(OH)D synthesis SNP (DHCR7; rs12785878) as an individual genetic instrument, a per allele reduction of 25(OH)D concentration (-4.2nmol/L ± SE 0.3nmol/L) was predicted to increase T2D risk by 5%, p = 0.004; Z score 2.84. This effect, however, was not seen in other 25(OH)D SNPs (GC rs2282679, CYP2R1 rs12794714) when used as an individual instrument. CONCLUSION: Our new data on this bidirectional Mendelian randomization study suggests that genetically instrumented T2D risk does not cause changes in 25(OH)D levels. However, genetically regulated 25(OH)D deficiency due to vitamin D synthesis gene (DHCR7) may influence the risk of T2D.


Asunto(s)
Diabetes Mellitus Tipo 2 , Deficiencia de Vitamina D , Pueblo Asiatico/genética , Diabetes Mellitus Tipo 2/genética , Humanos , Análisis de la Aleatorización Mendeliana , Polimorfismo de Nucleótido Simple , Vitamina D , Deficiencia de Vitamina D/genética
12.
Eur J Epidemiol ; 35(7): 685-697, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32383070

RESUMEN

Epidemiology studies suggested that low birthweight was associated with a higher risk of hypertension in later life. However, little is known about the causality of such associations. In our study, we evaluated the causal association of low birthweight with adulthood hypertension following a standard analytic protocol using the study-level data of 183,433 participants from 60 studies (CHARGE-BIG consortium), as well as that with blood pressure using publicly available summary-level genome-wide association data from EGG consortium of 153,781 participants, ICBP consortium and UK Biobank cohort together of 757,601 participants. We used seven SNPs as the instrumental variable in the study-level analysis and 47 SNPs in the summary-level analysis. In the study-level analyses, decreased birthweight was associated with a higher risk of hypertension in adults (the odds ratio per 1 standard deviation (SD) lower birthweight, 1.22; 95% CI 1.16 to 1.28), while no association was found between genetically instrumented birthweight and hypertension risk (instrumental odds ratio for causal effect per 1 SD lower birthweight, 0.97; 95% CI 0.68 to 1.41). Such results were consistent with that from the summary-level analyses, where the genetically determined low birthweight was not associated with blood pressure measurements either. One SD lower genetically determined birthweight was not associated with systolic blood pressure (ß = - 0.76, 95% CI - 2.45 to 1.08 mmHg), 0.06 mmHg lower diastolic blood pressure (ß = - 0.06, 95% CI - 0.93 to 0.87 mmHg), or pulse pressure (ß = - 0.65, 95% CI - 1.38 to 0.69 mmHg, all p > 0.05). Our findings suggest that the inverse association of birthweight with hypertension risk from observational studies was not supported by large Mendelian randomization analyses.


Asunto(s)
Peso al Nacer , Presión Sanguínea/genética , Hipertensión/epidemiología , Hipertensión/genética , Análisis de la Aleatorización Mendeliana/métodos , Adulto , Peso al Nacer/genética , Peso al Nacer/fisiología , Presión Sanguínea/fisiología , Índice de Masa Corporal , Femenino , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Masculino , Polimorfismo de Nucleótido Simple/genética
13.
Eur Heart J ; 45(24): 2155-2157, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38804264

Asunto(s)
Sesgo , Anciano , Humanos
14.
PLoS Med ; 16(6): e1002833, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31220083

RESUMEN

BACKGROUND: Iron is integral to many physiological processes, and variations in its levels, even within the normal range, can have implications for health. The objective of this study was to explore the broad clinical effects of varying iron status. METHODS AND FINDINGS: Genome-wide association study (GWAS) summary data obtained from 48,972 European individuals (55% female) across 19 cohorts in the Genetics of Iron Status Consortium were used to identify 3 genetic variants (rs1800562 and rs1799945 in the hemochromatosis gene [HFE] and rs855791 in the transmembrane protease serine 6 gene [TMPRSS6]) that associate with increased serum iron, ferritin, and transferrin saturation and decreased transferrin levels, thus serving as instruments for systemic iron status. Phenome-wide association study (PheWAS) of these instruments was performed on 424,439 European individuals (54% female) in the UK Biobank who were aged 40-69 years when recruited from 2006 to 2010, with their genetic data linked to Hospital Episode Statistics (HES) from April, 1995 to March, 2016. Two-sample summary data mendelian randomization (MR) analysis was performed to investigate the effect of varying iron status on outcomes across the human phenome. MR-PheWAS analysis for the 3 iron status genetic instruments was performed separately and then pooled by meta-analysis. Correction was made for testing of multiple correlated phenotypes using a 5% false discovery rate (FDR) threshold. Heterogeneity between MR estimates for different instruments was used to indicate possible bias due to effects of the genetic variants through pathways unrelated to iron status. There were 904 distinct phenotypes included in the MR-PheWAS analyses. After correcting for multiple testing, the 3 genetic instruments for systemic iron status demonstrated consistent evidence of a causal effect of higher iron status on decreasing risk of traits related to anemia (iron deficiency anemia: odds ratio [OR] scaled to a standard deviation [SD] increase in genetically determined serum iron levels 0.72, 95% confidence interval [CI] 0.64-0.81, P = 4 × 10-8) and hypercholesterolemia (hypercholesterolemia: OR 0.88, 95% CI 0.83-0.93, P = 2 × 10-5) and increasing risk of traits related to infection of the skin and related structures (cellulitis and abscess of the leg: OR 1.25, 95% CI 1.10-1.42, P = 6 × 10-4). The main limitations of this study relate to possible bias from pleiotropic effects of the considered genetic variants and misclassification of diagnoses in the HES data. Furthermore, this work only investigated participants with European ancestry, and the findings may not be applicable to other ethnic groups. CONCLUSIONS: Our findings offer novel, to our knowledge, insight into previously unreported effects of iron status, highlighting a potential protective effect of higher iron status on hypercholesterolemia and a detrimental role on risk of skin and skin structure infections. Given the modifiable and variable nature of iron status, these findings warrant further investigation.


Asunto(s)
Estudio de Asociación del Genoma Completo/métodos , Hierro/sangre , Análisis de la Aleatorización Mendeliana/métodos , Fenotipo , Adulto , Anciano , Biomarcadores/sangre , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
15.
Depress Anxiety ; 36(12): 1154-1162, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31609059

RESUMEN

BACKGROUND: This study aimed to explore the association between depression and body mass index (BMI), and to investigate whether genetic susceptibility to high BMI is different among individuals with or without depression. METHODS: We used data on 251,125 individuals of white British ancestry from the UK Biobank. We conducted Mendelian randomization (MR) analysis to test for a causal association between depression and BMI using a major depressive disorder (MDD)-related genetic risk score (GRSMDD ) as an instrument for depression. We also examined whether depression modifies genetic susceptibility to high BMI, by investigating the interaction between depression and the BMI-related GRSBMI . RESULTS: We found observational and genetic evidence for an association between depression and BMI (MR beta: 0.09, 95% confidence interval [CI] 0.04-0.13). Further, the contribution of genetic risk to high BMI was higher among individuals with depression compared to controls. Carrying 10 additional BMI increasing alleles was associated with 0.24 standard deviation (SD; 95%CI 0.23-0.25) higher BMI among depressed individuals compared to 0.20 SD (95%CI 0.19-0.21) higher in controls, which corresponds to 3.4 kg and 2.8 kg extra weight for an individual of average height. Amongst the individual loci, the evidence for interaction was most notable for a variant near MC4R, a gene known to affect both appetite regulation and the hypothalamic-pituitary adrenal axis (pinteraction = 5.7 × 10-5 ). CONCLUSION: Genetic predisposition to high BMI was higher among depressed than to nondepressed individuals. This study provides support for a possible role of MC4R in the link between depression and obesity.


Asunto(s)
Bancos de Muestras Biológicas , Índice de Masa Corporal , Trastorno Depresivo Mayor/genética , Predisposición Genética a la Enfermedad , Adulto , Anciano , Depresión/complicaciones , Depresión/genética , Trastorno Depresivo Mayor/complicaciones , Femenino , Humanos , Masculino , Análisis de la Aleatorización Mendeliana , Persona de Mediana Edad , Obesidad/complicaciones , Obesidad/genética , Receptor de Melanocortina Tipo 4/genética , Reino Unido , Población Blanca/genética
16.
Entropy (Basel) ; 21(8)2019 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-33267504

RESUMEN

The analytically solvable chaotic system (ASCS) is a promising chaotic system in chaos communication and radar fields. In this paper, we propose a maximum likelihood estimator (MLE) to estimate the frequency of ASCS, then a difference-integral (DI) detector is designed with the estimated frequency, and the symbols encoded in the signal are recovered. In the proposed method, the frequency parameter is estimated by an MLE based on the square power of the received signal. The Cramer-Rao lower bound in blind frequency estimation and the bit error performance in symbol detection are analyzed to assess the performance of the proposed method. Numerical results validate the analysis and demonstrate that the proposed symbol detector achieves the error performance with a little cost of 1 dB compared to the coherent detector. The robustness of the proposed method towards parameters is also verified through simulations.

17.
Circulation ; 135(24): 2373-2388, 2017 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-28500271

RESUMEN

BACKGROUND: The implications of different adiposity measures on cardiovascular disease etiology remain unclear. In this article, we quantify and contrast causal associations of central adiposity (waist-to-hip ratio adjusted for body mass index [WHRadjBMI]) and general adiposity (body mass index [BMI]) with cardiometabolic disease. METHODS: Ninety-seven independent single-nucleotide polymorphisms for BMI and 49 single-nucleotide polymorphisms for WHRadjBMI were used to conduct Mendelian randomization analyses in 14 prospective studies supplemented with coronary heart disease (CHD) data from CARDIoGRAMplusC4D (Coronary Artery Disease Genome-wide Replication and Meta-analysis [CARDIoGRAM] plus The Coronary Artery Disease [C4D] Genetics; combined total 66 842 cases), stroke from METASTROKE (12 389 ischemic stroke cases), type 2 diabetes mellitus from DIAGRAM (Diabetes Genetics Replication and Meta-analysis; 34 840 cases), and lipids from GLGC (Global Lipids Genetic Consortium; 213 500 participants) consortia. Primary outcomes were CHD, type 2 diabetes mellitus, and major stroke subtypes; secondary analyses included 18 cardiometabolic traits. RESULTS: Each one standard deviation (SD) higher WHRadjBMI (1 SD≈0.08 U) associated with a 48% excess risk of CHD (odds ratio [OR] for CHD, 1.48; 95% confidence interval [CI], 1.28-1.71), similar to findings for BMI (1 SD≈4.6 kg/m2; OR for CHD, 1.36; 95% CI, 1.22-1.52). Only WHRadjBMI increased risk of ischemic stroke (OR, 1.32; 95% CI, 1.03-1.70). For type 2 diabetes mellitus, both measures had large effects: OR, 1.82 (95% CI, 1.38-2.42) and OR, 1.98 (95% CI, 1.41-2.78) per 1 SD higher WHRadjBMI and BMI, respectively. Both WHRadjBMI and BMI were associated with higher left ventricular hypertrophy, glycemic traits, interleukin 6, and circulating lipids. WHRadjBMI was also associated with higher carotid intima-media thickness (39%; 95% CI, 9%-77% per 1 SD). CONCLUSIONS: Both general and central adiposity have causal effects on CHD and type 2 diabetes mellitus. Central adiposity may have a stronger effect on stroke risk. Future estimates of the burden of adiposity on health should include measures of central and general adiposity.


Asunto(s)
Adiposidad/genética , Distribución de la Grasa Corporal/métodos , Enfermedad Coronaria/genética , Diabetes Mellitus Tipo 2/genética , Análisis de la Aleatorización Mendeliana/métodos , Accidente Cerebrovascular/genética , Enfermedad Coronaria/epidemiología , Diabetes Mellitus Tipo 2/epidemiología , Humanos , Estudios Longitudinales , Estudios Observacionales como Asunto/métodos , Polimorfismo de Nucleótido Simple/genética , Estudios Prospectivos , Accidente Cerebrovascular/epidemiología
18.
J Am Chem Soc ; 140(48): 16807-16820, 2018 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-30398343

RESUMEN

Despite decades of intense research, the core structure of the methane C-H bond breaking diiron(IV) intermediate, Q, of soluble methane monooxygenase remains controversial, with conflicting reports supporting either a "diamond" diiron core structure or an open core structure. Early extended X-ray absorption fine structure (EXAFS) data assigned a short 2.46 Å Fe-Fe distance to Q (Shu et al. Science 1997, 275, 515 ) that is inconsistent with several theoretical studies and in conflict with our recent high-resolution Fe K-edge X-ray absorption spectroscopy (XAS) studies (Castillo et al. J. Am. Chem. Soc. 2017, 139, 18024 ). Herein, we revisit the EXAFS of Q using high-energy resolution fluorescence-detected extended X-ray absorption fine structure (HERFD-EXAFS) studies. The present data show no evidence for a short Fe-Fe distance, but rather a long 3.4 Å diiron distance, as observed in open core synthetic model complexes. The previously reported 2.46 Å feature plausibly arises from a background metallic iron contribution from the experimental setup, which is eliminated in HERFD-EXAFS due to the increased selectivity. Herein, we explore the origin of the short diiron feature in partial-fluorescent yield EXAFS measurements and discuss the diagnostic features of background metallic scattering contribution to the EXAFS of dilute biological samples. Lastly, differences in sample preparation and resultant sample inhomogeneity in rapid-freeze quenched samples for EXAFS analysis are discussed. The presented approaches have broad implications for EXAFS studies of all dilute iron-containing samples.


Asunto(s)
Hierro/química , Oxigenasas/química , Oxigenasas/ultraestructura , Espectroscopía de Absorción de Rayos X
19.
J Biol Inorg Chem ; 23(1): 155-165, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29218640

RESUMEN

Nonheme oxoiron(IV) complexes can serve as synthons for generating heterobimetallic oxo-bridged dimetal complexes by reaction with divalent metal complexes. The formation of FeIII-O-CrIII and FeIII-O-MnIII complexes is described herein. The latter complexes may serve as models for the FeIII-X-MnIII active sites of an emerging class of Fe/Mn enzymes represented by the Class 1c ribonucleotide reductase from Chlamydia trachomatis and the R2-like ligand-binding oxidase (R2lox) found in Mycobacterium tuberculosis. These synthetic complexes have been characterized by UV-Vis, resonance Raman, and X-ray absorption spectroscopy, as well as electrospray mass spectrometry. The FeIII-O-CrIII complexes exhibit a three-band UV-Vis pattern that differs from the simpler features associated with FeIII-O-FeIII complexes. The positions of these features are modulated by the nature of the supporting polydentate ligand on the iron center, and their bands intensify dramatically in two examples upon the binding of an axial cyanate or thiocyanate ligand trans to the oxo bridge. In contrast, the FeIII-O-MnIII complexes resemble FeIII-O-FeIII complexes more closely. Resonance Raman characterization of the FeIII-O-MIII complexes reveals an 18O-sensitive vibration in the range of 760-890 cm-1. This feature has been assigned to the asymmetric FeIII-O-MIII stretching mode and correlates reasonably with the Fe-O bond distance determined by EXAFS analysis. The likely binding of an acetate as a bridging ligand to the FeIII-O-MnIII complex 12 lays the foundation for further efforts to model the heterobimetallic active sites of Fe/Mn enzymes.


Asunto(s)
Complejos de Coordinación/química , Compuestos de Hierro/química , Hierro/química , Manganeso/química , Dominio Catalítico , Cromo/química , Complejos de Coordinación/síntesis química , Compuestos de Hierro/síntesis química , Ligandos , Estructura Molecular , Ribonucleótido Reductasas/química
20.
BMC Psychiatry ; 18(1): 297, 2018 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-30236085

RESUMEN

BACKGROUND: Obesity and depression are both highly prevalent public health disorders and evidence on their relationship is inconsistent. This study examined whether depressive symptoms are associated with current obesity, and further, whether obesity in turn is associated with an increased odds of depressive symptoms five years later after accounting for potential lifestyle confounders and depressive symptoms at baseline. METHODS: Data were obtained from the 1958 British birth cohort (N = 9217 for cross-sectional and 7340 for prospective analysis). Clinical Interview Schedule-Revised and Mental Health Inventory-5 were used for screening depressive symptoms at ages 45 and 50 years, respectively. General and central obesity were defined using measurements of body mass index (BMI) and waist circumference (WC) at 45 years, respectively. RESULTS: There was a cross-sectional association between depressive symptoms and obesity: participants with ≥2 depressive symptoms had 31% (95%CI 11% to 55%) higher odds of general and 26% higher odds of central obesity (95%CI 8% to 47%). In prospective analyses, both general and central obesity were associated with higher odds of depressive symptoms five years later among women but not in men (Pinteraction < 0.01). After adjustment for depressive symptoms at baseline, sociodemographic and lifestyle factors, women with general obesity had 38% (95% CI 7% to 77%) and women with central obesity 34% (95%CI 9% to 65%) higher odds of depression compared to others. CONCLUSIONS: Depressive symptoms are associated with concurrent obesity and related lifestyle factors among women and men in mid-life. Our study suggests that obesity in turn affects long-term risk of depressive symptoms in women but not in men, independently of concurrent associations, providing an important target group for the implementation of preventative strategies.


Asunto(s)
Depresión/epidemiología , Obesidad Abdominal/psicología , Obesidad/psicología , Índice de Masa Corporal , Estudios Transversales , Depresión/etiología , Femenino , Humanos , Estilo de Vida , Masculino , Persona de Mediana Edad , Obesidad/fisiopatología , Obesidad Abdominal/fisiopatología , Prevalencia , Estudios Prospectivos , Factores de Riesgo , Circunferencia de la Cintura
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