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1.
Artigo em Inglês | MEDLINE | ID: mdl-38435124

RESUMO

Purpose: This study sought to examine the potential association between serum Klotho levels and the prevalence of COPD in the United States. Patients and Methods: This study was a cross-sectional analysis involving 4361 adults aged 40-79 years participating in the US National Health and Nutrition Examination Survey (NHANES) conducted between 2013 and 2016. Our investigation utilized multivariate logistic regression and restricted cubic spline (RCS) regression to explore the potential correlation between serum Klotho concentrations and the prevalence of COPD. Additionally, we conducted stratified and interaction analyses to evaluate the consistency and potential modifiers of this relationship. Results: In this study encompassing 4631 patients (with an average age of 57.6 years, 47.5% of whom were male), 445 individuals (10.2%) were identified as having COPD. In the fully adjusted model, ln-transformed serum Klotho was negatively associated with COPD (OR = 0.71; 95% CI: 0.51-0.99; p = 0.043). Meanwhile, compared with quartile 1, serum Klotho levels in quartiles 2-4 yielded odds ratios (ORs) (95% CI) for COPD were 0.84 (0.63~1.11), 0.76 (0.56~1.02), 0.84 (0.62~1.13), respectively. A negative relationship was observed between the ln-transformed serum Klotho and occurrence of COPD (nonlinear: p = 0.140). the association between ln-transformed serum Klotho and COPD were stable in stratified analyses. Conclusion: Serum Klotho was negatively associated with the incidence of COPD, when ln-transformed Klotho concentration increased by 1 unit, the risk of COPD was 29% lower.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Adulto , Pessoa de Meia-Idade , Humanos , Masculino , Idoso , Feminino , Estudos Transversais , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Inquéritos Nutricionais , Razão de Chances
2.
Front Endocrinol (Lausanne) ; 15: 1288170, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38390198

RESUMO

Objective: Low back pain (LBP) has been associated with education in previous observational studies, but the causality remains unclear. This study aims to assess the impact of education on LBP and to explore mediation by multiple lifestyle factors. Design: Univariable Mendelian randomization (MR) was performed to examine the overall effect of education on LBP. Subsequently, multivariable MR was conducted to assess both the direct effect of education on LBP and the influence of potential mediators. Indirect effects were estimated using either the coefficient product method or the difference method, and the proportion of mediation was calculated by dividing the indirect effect by the total effect. The observational study utilized data from the NHANES database collected between 1999 and 2004, and included 15,580 participants aged 20 years and above. Results: Increasing education by 4.2 years leads to a 48% reduction in the risk of LBP (OR=0.52; 95% CI: 0.46 to 0.59). Compared to individuals with less than a high school education, those with education beyond high school have a 28% lower risk of LBP (OR=0.72; 95% CI: 0.63 to 0.83). In the MR study, smoking accounts for 12.8% (95% CI: 1.04% to 20.8%) of the total effect, while BMI accounts for 5.9% (95% CI: 2.99% to 8.55%). The combined mediation effect of smoking and BMI is 27.6% (95% CI: 23.99% to 32.7%). In the NHANES study, only smoking exhibits a mediating effect, accounting for 34.3% (95% CI: 21.07% to 41.65%) of the effect, while BMI does not demonstrate a mediating role. Conclusions: Higher levels of education provide a protective effect against the risk of LBP. Additionally, implementing interventions to reduce smoking and promote weight loss among individuals with lower levels of education can also decrease this risk.


Assuntos
Índice de Massa Corporal , Dor Lombar , Fumar , Humanos , Dor Lombar/epidemiologia , Dor Lombar/etiologia , Dor Lombar/genética , Análise da Randomização Mendeliana , Inquéritos Nutricionais/estatística & dados numéricos , Fumar/efeitos adversos , Fumar/epidemiologia , Adulto Jovem , Adulto , Escolaridade
3.
J Bone Miner Metab ; 42(1): 90-98, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38157037

RESUMO

INTRODUCTION: Previous research has confirmed that patients with type 2 diabetes mellitus tend to have higher bone mineral density (BMD), but it is unknown whether this pattern holds true for individuals without diabetes. This Mendelian randomization (MR) study aims to investigate the potential causal relationship between various glycemic trait (including fasting glucose, fasting insulin, 2-h postprandial glucose, and glycated hemoglobin) and BMD in non-diabetic individuals. The investigation focuses on different age groups (15-30, 30-45, 45-60, and 60 + years) and various skeletal sites (forearm, lumbar spine, and hip). MATERIALS AND METHODS: We utilized genome-wide association study data from large population-based cohorts to identify robust instrumental variables for each glycemic traits parameter. Our primary analysis employed the inverse-variance weighted method, with sensitivity analyses conducted using MR-Egger, weighted median, MR-PRESSO, and multivariable MR methods to assess the robustness and potential horizontal pleiotropy of the study results. RESULTS: Fasting insulin showed a negative modulating relationship on both lumbar spine and forearm. However, these associations were only nominally significant. No significant causal association was observed between blood glucose traits and BMD across the different age groups. The direction of fasting insulin's causal effects on BMD showed inconsistency between genders, with potentially decreased BMD in women with high fasting insulin levels and an increasing trend in BMD in men. CONCLUSIONS: In the non-diabetic population, currently available evidence does not support a causal relationship between glycemic traits and BMD. However, further investigation is warranted considering the observed gender differences.


Assuntos
Diabetes Mellitus Tipo 2 , Análise da Randomização Mendeliana , Humanos , Feminino , Masculino , Adolescente , Densidade Óssea/genética , Diabetes Mellitus Tipo 2/genética , Estudo de Associação Genômica Ampla , Insulina , Glucose , Polimorfismo de Nucleotídeo Único
4.
Int J Chron Obstruct Pulmon Dis ; 18: 2267-2276, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37868623

RESUMO

Purpose: This study aims to explore the association between red cell index (RCI) and hospital mortality in Chronic Obstructive Pulmonary Disease (COPD) patients in the intensive care unit. Patients and Methods: This was a retrospective cohort research. The study included 821 COPD patients. Clinical data from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database was conducted. Multivariate logistic regression analysis was used to assess the correlation between RCI and in-hospital mortality. Age, SOFA score, diabetes mellitus, cerebrovascular disease, congestive heart failure and mechanical ventilation were considered for subgroup analysis. Results: This study comprised 821 patients, of which 16.5% (124/821) suffered hospital mortality. In the multivariate logistic regression model, RCI was positively associated with hospital mortality, each unit increase in RCI was associated with a 3% increase in hospital mortality (odds ratio [OR] =1.03; 95% confidence interval [95CI%] =1.01-1.06). Meanwhile, compare with the lowest RCI group, the highest RCI groups tended to have higher risks of hospital mortality (OR [95% CI] 2.33 [1.27-4.27]). Additionally, subgroup analysis result was persistent among all the groups. Conclusion: Higher RCI was positively associated with a higher risk of mortality in critically ill patients with COPD. Further investigation is necessary to confirm these findings.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Humanos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/terapia , Doença Pulmonar Obstrutiva Crônica/complicações , Mortalidade Hospitalar , Estudos Retrospectivos , Índices de Eritrócitos , Unidades de Terapia Intensiva
5.
PLoS One ; 18(8): e0289252, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37527259

RESUMO

BACKGROUND: Observational studies suggest physical activity (PA) enhances intelligence, while sedentary behavior (SB) poses a risk. However, causality remains unclear. METHODS: We extracted genetic instruments from large genome-wide association studies summary data and employed an inverse-variance weighted (IVW) approach within a random-effects model as the primary method of Mendelian randomization (MR) analysis to estimate the overall effect of various physical activity statuses on intelligence. To assess IVW stability and MR sensitivity, we also utilized supplementary methods including weighted median, MR-Egger, and MR-PRESSO. Furthermore, multivariable MR analysis was conducted to examine the independent effects of each physical activity trait on intelligence. RESULTS: The MR primary results indicated that LST was negatively associated with intelligence (ß = -0.133, 95%CI: -0.177 to -0.090, p = 1.34×10-9), while SBW (ß = 0.261, 95% CI: 0.059 to 0.463, p = 0.011) may have a positive effect on intelligence; however, MVPA and SC did not show significant effects on intelligence. Inverse causality analyses demonstrated intelligence significantly influenced all physical activity states. CONCLUSIONS: Our study highlights a bidirectional causal relationship between physical activity states and intelligence.


Assuntos
Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Causalidade , Exercício Físico , Inteligência/genética
6.
Entropy (Basel) ; 25(6)2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37372244

RESUMO

This paper focuses on the adaptive control problem of a class of uncertain time-delay nonlinear cyber-physical systems (CPSs) with both unknown time-varying deception attacks and full-state constraints. Since the sensors are disturbed by external deception attacks making the system state variables unknown, this paper first establishes a new backstepping control strategy based on compromised variables and uses dynamic surface techniques to solve the disadvantages of the huge computational effort of the backstepping technique, and then establishes attack compensators to mitigate the impact of unknown attack signals on the control performance. Second, the barrier Lyapunov function (BLF) is introduced to restrict the state variables. In addition, the unknown nonlinear terms of the system are approximated using radial basis function (RBF) neural networks, and the Lyapunov-Krasovskii function (LKF) is introduced to eliminate the influence of the unknown time-delay terms. Finally, an adaptive resilient controller is designed to ensure that the system state variables converge and satisfy the predefined state constraints, all signals of the closed-loop system are semi-globally uniformly ultimately bounded under the premise that the error variables converge to an adjustable neighborhood of origin. The numerical simulation experiments verify the validity of the theoretical results.

7.
Ann Med ; 55(1): 2226908, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37353997

RESUMO

OBJECTIVE: To conduct a systematic review and updated meta-analysis on the potential association between endothelial nitric oxide synthase (eNOS) 4a/b polymorphism and the risk of developing diabetic retinopathy (DR) in patients with type 2 diabetes mellitus (T2DM) and to identify possible clinical biomarkers for early screening of DR. MATERIALS AND METHODS: A meta-analysis based on case-control or cross-sectional studies was conducted to examine the correlation between eNOS 4a/b polymorphism and DR. Pooled odds ratio (OR) and 95% confidence interval (CI) were used to estimate the association strength. RESULTS: We included 19 studies, covering 7838 subjects. An association was observed in Caucasians (allelic model: OR = 1.273, 95% CI: 1.006-1.610, p = .045; recessive model: OR = 0.575, 95% CI: 0.371-0.892, p = .014; dominant model: OR = 1.268, 95% CI: 1.052-1.528, p = .013; homozygote model: OR = 1.833, 95% CI: 1.176-2.856, p = .007). Moreover, population-based studies have indicated an association between eNOS 4a/b polymorphism and DR susceptibility. CONCLUSIONS: The present study showed that intron 4a allele of eNOS 4a/b is a risk factor for DR in Caucasians with T2DM. Thus, eNOS 4a/b may be used as a biomarker for the early screening and diagnosis of DR in Caucasian T2DM patients.Key messagesEndothelial nitric oxide synthase 4a/b gene polymorphism is not associated with the risk of developing diabetic retinopathy in the overall population, Asians, or Chinese Han patients with type 2 diabetes. However, 4a is a risk factor for the development of diabetic retinopathy in Caucasians.Endothelial nitric oxide synthase 4a/b gene polymorphism is not associated with the type of diabetic retinopathy.


Assuntos
Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Óxido Nítrico Sintase Tipo III , Humanos , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Retinopatia Diabética/etiologia , Retinopatia Diabética/genética , Predisposição Genética para Doença , Genótipo , Óxido Nítrico Sintase Tipo III/genética , Polimorfismo Genético
8.
Materials (Basel) ; 6(2): 551-564, 2013 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-28809325

RESUMO

The thermal shock resistance of ceramics depends on not only the mechanical and thermal properties of materials, but also the external constraint and thermal condition. So, in order to study the actual situation in its service process, a temperature-dependent thermal shock resistance model for ultra-high temperature ceramics considering the effects of the thermal environment and external constraint was established based on the existing theory. The present work mainly focused on the adjustment of the stress reduction factor according to different thermal shock situations. The influences of external constraint on both critical rupture temperature difference and the second thermal shock resistance parameter in either case of rapid heating or cooling conditions had been studied based on this model. The results show the necessity of adjustment of the stress reduction factor in different thermal shock situations and the limitations of the applicable range of the second thermal shock resistance parameter. Furthermore, the model was validated by the finite element method.

9.
J Tradit Chin Med ; 32(2): 249-55, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22876452

RESUMO

OBJECTIVE: To study the use of a bone-strengthening pill to treat ischemic necrosis of the femoral head. METHODS: A model of castration in rats with osteoporosis and a model of ischemic necrosis in the bilateral femoral heads of young rats were used to detect bone density, bone formation measurements, lipid deposition in the femoral head, the distribution of capillaries in the femoral head and other relevant biochemical indices. RESULTS: In model rats, bone-strengthening pills were able to increase the bone density, the unit volume of bony trabeculae, the width of bony trabeculae, and the unit volume of the bony cortex. They could also enhance the mineral apposition rate in the femoral head and the seam width of osteoid deposition. Furthermore, there was a reduction in lipid deposition in the femoral head, and enriched distribution of arteries in the femoral head. Bone-related biochemical detections showed an increase in alkaline phosphatase staining and a decrease in tartaric acidic phosphatase staining. CONCLUSION: The results show that bone-strengthening pills can obviously promote bony growth, cause an increase in bone density, restore blood circulation, inhibit the occurrence and development of bony necrosis, and accelerate the repair of necrotic bones, with no toxic side-effects.


Assuntos
Necrose da Cabeça do Fêmur/tratamento farmacológico , Medicina Tradicional Chinesa , Fosfatase Alcalina/sangue , Animais , Densidade Óssea/efeitos dos fármacos , Feminino , Necrose da Cabeça do Fêmur/metabolismo , Ratos , Ratos Wistar
10.
Phys Rev Lett ; 94(7): 077803, 2005 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-15783855

RESUMO

The mechanism responsible for liquid crystal (LC) alignment on mechanically buffed or UV exposed polymer films is poorly understood. A comprehensive study of LC alignment on variously prepared substrates unequivocally shows that the anisotropy in the surface roughness of the substrate completely determines the direction of LC alignment. In all the cases studied, including those where an anchoring transition occurs with temperature, the LC director (re)aligns in the directions of low roughness.

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