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1.
J Electrocardiol ; 77: 41-45, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36584548

RESUMO

OBJECTIVES: Predictors for increased stroke mortality identify those who may need closer monitoring and better hospital care. While the link between premature ventricular complexes (PVCs) and incident ischemic stroke has been reported, studies on the association with fatal stroke are non-existent. MATERIALS AND METHODS: We examined the association of PVCs with stroke mortality in 8047 participants (56.5 ± 0.39 years, 53% women, 80.9% Non-Hispanic Whites) without prior history of stroke from the Third National Health and Nutrition Examination Survey. National Death Index was used to identify the date and cause of death. PVCs were detected from 12­lead standard electrocardiograms. Cox proportional hazard analysis was used to examine the association between any PVC with stroke mortality. RESULTS: Approximately 2.1% (n = 134) participants had PVCs at baseline. Over a median follow-up of 22 years, 337 fatal strokes occurred. More strokes occurred in participants with baseline PVCs compared to those without (unadjusted cumulative incidence of stroke 9.5% vs. 2.5% respectively, p-value 0.001). In a multivariable-adjusted model, the presence of PVC was associated with an increased risk of stroke mortality (HR (95%CI): 2.50 (1.15-5.43). This association was stronger in participants with coronary heart disease (CHD) than those without it (HR (95%CI): 5.98 (2.2-16.2) vs. 1.97 (0.75-5.1) respectively; interaction-p = 0.008). CONCLUSIONS: PVCs are associated with an increased risk of stroke mortality, especially among individuals with CHD. Whether improved hospital care or modifying PVCs could change outcomes should be examined in prospective studies.


Assuntos
Doença das Coronárias , Acidente Vascular Cerebral , Complexos Ventriculares Prematuros , Humanos , Feminino , Masculino , Eletrocardiografia , Estudos Prospectivos , Inquéritos Nutricionais , Acidente Vascular Cerebral/diagnóstico , Incidência , Complexos Ventriculares Prematuros/diagnóstico
2.
Artigo em Chinês | MEDLINE | ID: mdl-33691365

RESUMO

Objective: To analyze the levels of T lymphocyte subsets (CD3, CD4, CD8 and CD4/CD8) in patients with paraquat poisoning, and to explore the relationship between the changes of T lymphocyte subsets and the prognosis of pulmonary fibrosis. Methods: In October 2019, a total of 47 patients with oral 20% paraquat low water solvent poisoning in Guangzhou 12th people's Hospital from June 2018 to June 2019 were selected as the research objects. Patients were divided into early death group (16 cases died within 2 weeks) and non early death group (31 cases survived more than 2 weeks) . The non early death group was divided into pulmonary fibrosis group (23 cases) and normal lung group (8 cases) . 20 healthy people in the same period were randomly selected as the control group. The neutrophils (N) , C reaction protein (CRP) , alanine aminotransferase (ALT) , creatinine (Cr) , amylase (aAMY) , creatine kinase isoenzyme (CKMB) , pH, HCO(3)(-), blood oxygen saturation (SO(2)) and lactic acid (Lac) of patients poisoned within 3 d were examined every day. Independent sample t-test was used for inter group comparison, and paired sample t-test was used for intra group comparison. Results: Compared with non early death group, the levels of N, CRP, ALT, Cr, aAMY, CKMB and Lac in early death group increased (P<0.05) , while pH and HCO(3)(-) decreased (P<0.05) . Compared with the control group, the levels of CD3, CD4 and CD4/CD8 were decreased on the first day in the early death group and non early death group (P<0.05) , and the levels of CD3, CD4 and CD4/CD8 were decreased on the 15th day in the pulmonary fibrosis group (P<0.05) . Compared with the normal lung group, the levels of CD3, CD4 and CD4/CD8 in the pulmonary fibrosis group decreased on the 15th day (P<0.05) . Conclusion: The persistent low cellular immune function in patients with paraquat poisoning is related to the progress of pulmonary fibrosis, which is an important factor affecting the prognosis of patients with pulmonary fibrosis.


Assuntos
Paraquat , Fibrose Pulmonar , Creatinina , Humanos , Prognóstico , Fibrose Pulmonar/induzido quimicamente , Subpopulações de Linfócitos T
3.
J Electrocardiol ; 60: 126-130, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32361087

RESUMO

BACKGROUND: Recent evidence suggests a link between myocardial infarction and stroke risk, but it is unclear whether such risk exists with electrocardiographic myocardial injury in otherwise healthy individuals. Therefore, we explored the association of myocardial injury with stroke mortality in participants free of cardiovascular disease. METHODS: This analysis included 6017 participants (58.4 ± 13.4 years, 54.1% women, 50.3% white) from the Third National Health and Nutrition Examination Survey. Cardiac infarction/injury score (CIIS), a weighted scoring system composed of several electrocardiographic waveform components related to myocardial injury and ischemia, was used to define myocardial injury. Stroke mortality was ascertained using the National Death Index during follow-up. Multivariable adjusted Cox proportional hazard analysis was used to examine the association between baseline myocardial injury and risk of stroke mortality. RESULTS: Over a median follow-up of 14 years, 152 stroke deaths occurred. Stroke mortality was more common in those with than those without myocardial injury (3.8% vs. 2.1%, respectively; p = 0.0003). In a model adjusted for potential confounders, the myocardial injury was associated with a 44% increased risk of stroke mortality (HR (95%CI):1.44(1.02-2.03)). In a similar model, each 1 CIIS score point increase was associated with a 2% increase in the risk of stroke mortality (HR (95%CI):1.02 (1.00-1.04), p = 0.01). CONCLUSIONS: Electrocardiographic myocardial injury in cardiovascular disease-free adults is associated with an increased risk of stroke mortality suggesting a potential link between asymptomatic myocardial injury and risk of cardiac thromboembolism. Whether screening and management of myocardial injury would reduce such risk requires further investigation.


Assuntos
Infarto do Miocárdio , Acidente Vascular Cerebral , Adulto , Eletrocardiografia , Feminino , Humanos , Masculino , Inquéritos Nutricionais , Modelos de Riscos Proporcionais , Fatores de Risco
4.
J Microsc ; 272(2): 145-150, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30338530

RESUMO

We recently developed two quantitative fluorescence resonance energy transfer (FRET) measurement methods based on spectral unmixing of emission spectra (IIem-spFRET) and excitation-emission spectra (ExEm-spFRET), respectively. We here evaluated robustness of the two methods by implementing them on a self-assembled quantitative FRET measurement system using the cells expressing different constructs. For the cells with larger signal-to-noise (S/N) ratio (>9), the two methods obtained consistent FRET efficiency (E) values and total concentration ratio (RC) values of acceptor to donor for all constructs; for the cells with 3 < S/N < 9, IIem-spFRET obtained bigger RC values than the expected value for VCV construct; for the cells with S/N < 3, although IIem-spFRET method obtained inaccurate E and RC values for VCV construct, the two methods also obtained consistent E and RC values for all other constructs. Collectively, both ExEm-spFRET and IIem-spFRET methods are very applicable for live-cell FRET measurement, and ExEm-spFRET has superior robustness especially for the cells with low S/N ratio. LAY DESCRIPTION: Fluorescent proteins (FPs)-based fluorescence resonance energy transfer (FRET) has been widely used as a powerful technique to study protein-protein interaction and stoichiometry of macromolecular complexes in living cells. There are two key issues for quantitative FRET measurement especially in living cells: donor emission crosstalk (donor fluorescence is collected in acceptor detection channel) and acceptor excitation crosstalk (acceptor is excited directly under donor excitation) due to the spectral overlap of FPs. Two-wavelengths excitation-based spectral linear unmixing of emission spectra can resolve donor emission crosstalk due to the obvious difference in emission spectra between donor and acceptor, but additional reference is necessary for the correction of acceptor excitation crosstalk. Spectral unmixing of excitation-emission spectra has inherent ability to resolve donor emission crosstalk and acceptor excitation crosstalk simultaneously without additional reference. We recently developed two quantitative FRET measurement methods based on spectral unmixing of emission spectra (IIem-spFRET) and excitation-emission spectra (ExEm-spFRET), respectively. We here evaluate robustness of the two methods by implementing them on a self-assembled quantitative FRET measurement system using the same cells expressing different constructs under different signal-to-noise (S/N) ratios. For the cells with S/N > 9, the two methods obtained consistent FRET efficiency (E) values and total concentration ratio (RC) values of acceptor to donor for all constructs; for the cells with 3 < S/N < 9, IIem-spFRET obtained bigger RC values than the expected value for VCV construct; for the cells with S/N < 3, although IIem-spFRET method obtained inaccurate E and RC values for VCV construct, the two methods also obtained consistent E and RC values for all other constructs. Collectively, our experimental results demonstrate that both ExEm-spFRET and IIem-spFRET methods are very applicable for live-cell FRET measurement, and ExEm-spFRET has superior robustness especially for the cells high E and low S/N ratio.


Assuntos
Microscopia/métodos , Análise Espectral/métodos , Transferência Ressonante de Energia de Fluorescência , Células Hep G2 , Humanos , Proteínas Luminescentes
5.
J Microsc ; 269(1): 66-77, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28758212

RESUMO

Simultaneous spectral unmixing of excitation and emission spectra (ExEm unmixing) has inherent ability resolving spectral crosstalks, two key issues of quantitative fluorescence resonance energy transfer (FRET) measurement, of both the excitation and emission spectra between donor and acceptor without additional corrections. We here set up a filter-based multichannel wide-field microscope for ExEm unmixing-based FRET imaging (m-ExEm-spFRET) containing a constant system correction factor (fsc ) for a stable system. We performed m-ExEm-spFRET with four- and two-wavelength excitation respectively on our system to quantitatively image single living cells expressing FRET tandem constructs, and obtained accurate FRET efficiency (E) and concentration ratio of acceptor to donor (RC ). We also performed m-ExEm-spFRET imaging for single living cells coexpressing CFP-Bax and YFP-Bax, and found that the E values were about 0 for control cells and about 28% for staurosporin-treated cells when RC were larger than 1, indicating that staurosporin induced significant oligomerisation.

6.
J Microsc ; 270(3): 335-342, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29437234

RESUMO

Quantum yield ratio (QA /QD ) and absorption ratio (KA /KD ) in all excitation wavelengths used between acceptor and donor are indispensable to quantitative fluorescence resonance energy transfer (FRET) measurement based on linearly unmixing excitation-emission spectra (ExEm-spFRET). We here describe an approach to simultaneously measure QA /QD and KA /KD values by linearly unmixing the excitation-emission spectra of at least two different donor-acceptor tandem constructs with unknown FRET efficiency. To measure the QA /QD and KA /KD values of Venus (V) to Cerulean (C), we used a wide-field fluorescence microscope to image living HepG2 cells separately expressing each of four different C-V tandem constructs at different emission wavelengths with 435 nm and 470 nm excitation respectively to obtain the corresponding excitation-emission spectrum (SDA ). Every SDA was linearly unmixed into the contributions (weights) of three excitation-emission spectra of donor (WD ) and acceptor (WA ) as well as donor-acceptor sensitisation (WS ). Plot of WS /WD versus WA /WD for the four C-V plasmids from at least 40 cells indicated a linear relationship with 1.865 of absolute intercept (QA /QD ) and 0.273 of the reciprocal of slope (KA /KD ), which was validated by quantitative FRET measurements adopting 1.865 of QA /QD and 0.273 of KA /KD for C32V, C5V, CVC and VCV constructs respectively in living HepG2 cells.

7.
Neoplasma ; 65(2): 216-221, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29534582

RESUMO

This meta-analysis aimed to clarify the actual association between the phosphodiesterase type 5 inhibitors (PDE5-Is) use and the risk of melanoma in erectile dysfunction (ED) patients. A systematic literature search was conducted in online databases in October, 2016 to identify studies focusing on the association between PDE5-Is use and the risk of melanoma. Summarized multivariate adjusted risk ratios (RRs) and 95% confidence intervals (CIs) were calculated to assess the strength of associations. A total of six clinical trials containing more than one million participants were included. ED patients  using PDE5-Is shared a significant high risk of melanoma (RR=1.12, 95% CI=1.03-1.21, p=0.006). Positive associations were observed in all kinds of prescriptions: single prescription (RR=1.20, 95% CI=1.06-1.35, p=0.003), medium number of prescription (RR=1.15, 95% CI=1.01-1.30, p=0.03), and high number of prescription (RR=1.18, 95% CI=1.05-1.34, P=0.006). Additionally, PDE5-Is were also found to be significantly associated with increased risk of basal cell carcinoma (RR=1.14, 95% CI=1.09-1.19, p<0.00001). Our study indicates that PDE5-Is use could significantly increase the risk of melanoma and basal cell carcinoma. However, the risk of melanoma did not rise significantly with the increased number of prescriptions. Consequently, owing to the lack of information about other potential synergistic factors, it is difficult for us to make a solid conclusion that application of PDE5-Is is the direct cause of increased risk of melanoma. Their relationship needs to be validated by further evidences.


Assuntos
Carcinoma Basocelular/induzido quimicamente , Disfunção Erétil/tratamento farmacológico , Melanoma/induzido quimicamente , Inibidores da Fosfodiesterase 5/efeitos adversos , Humanos , Masculino , Inibidores da Fosfodiesterase 5/uso terapêutico , Medição de Risco
8.
Zhonghua Fu Chan Ke Za Zhi ; 53(1): 23-30, 2018 Jan 25.
Artigo em Chinês | MEDLINE | ID: mdl-29374882

RESUMO

Objective: Explore the value of anti-Müllerian hormone (AMH) in predicting pregnant outcomes of polycystic ovary syndrome (PCOS) patients undergone assisted reproductive technology. Methods: The study totally recruited 1 697 patients who underwent the first in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) cycle in Sun Yat-sen Memorial Hospital from the January 2014 to December 2015. The patients were divided into two groups based on the age<35 (n=758) and ≥35 years old (n=939) , compare the basic data and pregnant outcomes of controlled ovarian hyerstimulation. Spearman correlation method was conducted to analyze the relations between AMH and clinical outcomes. The logistic regression method and partial correlation analysis were used to judge the main factors which determine pregnancy outcomes by controlled the confounding factors. The receiver operating characteristic curve (ROC) was used to evaluate the predictive sensitivity and specificity of AMH. Results: In the group of PCOS patient younger than 35 years, AMH were correlated with the number of antral follicles (r=0.388) and retrieved oocytes (r=0.235) . When the effect of total dosage and starting dosage of gonadotropin were controlled, AMH was still significantly associated with the number of retrieved oocytes (P<0.05) . AMH had no predictive value for the clinical pregnancy of PCOS patient younger than 35 years (area under ROC curve=0.481, P=0.768) . In the group of PCOS patient≥35 years old, AMH were correlated with the number of antral follicles (r=0.450) , retrieved oocytes (r=0.399) , available embryo (r=0.336) and high quality embryo (r=0.235) . When the effect of total dosage and starting dosage of gonadotropin were controlled, the correlations were still significant between those indexes (all P<0.05) . AMH had no predictive value for the clinical pregnancy of PCOS patient ≥35 years old (area under ROC curve=0.535, P=0.560) . However, the clinical pregnancy rate of the group of PCOS patient ≥35 years old was slightly higher than the control group (P=0.062) . Conclusions: AMH has no predictive value for the pregnancy outcome of PCOS patient. The pregnancy rate of PCOS patient ≥35 years old is slightly higher than the younger group, because the PCOS patient may have better ovarian reserve.


Assuntos
Hormônio Antimülleriano/sangue , Fertilização in vitro/métodos , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/metabolismo , Síndrome do Ovário Policístico/terapia , Resultado da Gravidez , Técnicas de Reprodução Assistida , Adolescente , Adulto , Fatores Etários , Hormônio Antimülleriano/metabolismo , Feminino , Humanos , Folículo Ovariano/metabolismo , Gravidez , Taxa de Gravidez , Prognóstico , Curva ROC , Sensibilidade e Especificidade , Injeções de Esperma Intracitoplásmicas , Resultado do Tratamento
9.
Neuroimage ; 125: 363-377, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26525654

RESUMO

Although MRI is the gold standard for the diagnosis and monitoring of multiple sclerosis (MS), current conventional MRI techniques often fail to detect cortical alterations and provide little information about gliosis, axonal damage and myelin status of lesioned areas. Diffusion tensor imaging (DTI) and diffusion kurtosis imaging (DKI) provide sensitive and complementary measures of the neural tissue microstructure. Additionally, specific white matter tract integrity (WMTI) metrics modelling the diffusion in white matter were recently derived. In the current study we used the well-characterized cuprizone mouse model of central nervous system demyelination to assess the temporal evolution of diffusion tensor (DT), diffusion kurtosis tensor (DK) and WMTI-derived metrics following acute inflammatory demyelination and spontaneous remyelination. While DT-derived metrics were unable to detect cuprizone induced cortical alterations, the mean kurtosis (MK) and radial kurtosis (RK) were found decreased under cuprizone administration, as compared to age-matched controls, in both the motor and somatosensory cortices. The MK remained decreased in the motor cortices at the end of the recovery period, reflecting long lasting impairment of myelination. In white matter, DT, DK and WMTI-derived metrics enabled the detection of cuprizone induced changes differentially according to the stage and the severity of the lesion. More specifically, the MK, the RK and the axonal water fraction (AWF) were the most sensitive for the detection of cuprizone induced changes in the genu of the corpus callosum, a region less affected by cuprizone administration. Additionally, microgliosis was associated with an increase of MK and RK during the acute inflammatory demyelination phase. In regions undergoing severe demyelination, namely the body and splenium of the corpus callosum, DT-derived metrics, notably the mean diffusion (MD) and radial diffusion (RD), were among the best discriminators between cuprizone and control groups, hence highlighting their ability to detect both acute and long lasting changes. Interestingly, WMTI-derived metrics showed the aptitude to distinguish between the different stages of the disease. Both the intra-axonal diffusivity (Da) and the AWF were found to be decreased in the cuprizone treated group, Da specifically decreased during the acute inflammatory demyelinating phase whereas the AWF decrease was associated to the spontaneous remyelination and the recovery period. Altogether our results demonstrate that DKI is sensitive to alterations of cortical areas and provides, along with WMTI metrics, information that is complementary to DT-derived metrics for the characterization of demyelination in both white and grey matter and subsequent inflammatory processes associated with a demyelinating event.


Assuntos
Córtex Cerebral/efeitos dos fármacos , Doenças Desmielinizantes/patologia , Imagem de Tensor de Difusão/métodos , Substância Branca/patologia , Animais , Córtex Cerebral/patologia , Quelantes/toxicidade , Cuprizona/toxicidade , Doenças Desmielinizantes/induzido quimicamente , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Endogâmicos C57BL
11.
J Clin Med ; 13(16)2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39201088

RESUMO

Background: Subclinical myocardial injury (SCMI) is associated with an increased risk of poor cardiovascular disease (CVD) outcomes. Understanding the underlying risk factors for SCMI is crucial for the prevention and management of CVD. We hypothesized that atherogenic dyslipidemia, a combination of high triglycerides (TG) and low high-density lipoprotein cholesterol (HDL-C), is associated with an increased risk of SCMI. Methods: This analysis from the third National Health and Nutrition Examination Survey (NHANES-III) included 7093 participants (age 59.3 ± 13.4 years, 52.8% women, and 49.4% White) free of CVD. Atherogenic dyslipidemia was defined as TG ≥ 150 mg/dL and HDL-C < 40 mg/dL in men or <50 mg/dL in women. A validated electrocardiographic-based cardiac infarction injury score (CIIS) ≥ 10 was considered positive for SCMI. Multivariable logistic regression analysis was used to examine the association of different combinations of TG and HDL-C groups, including atherogenic dyslipidemia with SCMI. Results: About 22.5% (n = 1594) of participants had atherogenic dyslipidemia, and 26.3% (n = 1862) had SCMI. Compared to participants with normal TG and normal HDL-C, those with atherogenic dyslipidemia had a higher prevalence of SCMI (31.2% vs. 23.9%, p-value < 0.001). In a multivariable logistic regression model, atherogenic dyslipidemia was associated with the highest odds of SCMI followed by high TG/normal HDL-C, then low HDL-C/normal TG [OR (95% CI): 131 (1.14, 1.52), 1.13 (0.97, 1.33), and 1.01 (0.86, 1.20), respectively). Conclusions: Atherogenic dyslipidemia is associated with a higher risk of SCMI, which highlights the role of nontraditional risk factors in the development of subclinical CVD.

12.
Am J Med Sci ; 367(6): 352-356, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38301824

RESUMO

BACKGROUND: We explored whether the reported racial differences in subclinical myocardial injury (SCMI) are due to variations in the prevalence or differential impact of the SCMI risk factors. METHODS: This analysis included 3074 Whites, 1337 Blacks, and 1441 Mexican Americans from the Third National Health and Nutrition Examination Survey who were free of cardiovascular disease. SCMI was defined from standard electrocardiograms as a cardiac infarction/injury score ≥ 10 points. Multivariable logistic regression analysis was used to assess the association of SCMI with its risk factors stratified by race. Multiplicative interaction between each risk factor and race was also examined. RESULTS: Overall prevalence of SCMI was 20.3%, with Mexican Americans exhibiting a lower prevalence than Whites and Blacks (16.5%, 20.4%, and 20.7%, respectively). Whites had more prevalence of dyslipidemia and smoking. Mexican Americans had more diabetes, while Blacks had more hypertension, obesity, and left ventricular hypertrophy. Significant risk factors for SCMI were older age, lower income (<20 K), smoking, diabetes, and no regular exercise. The association of SCMI with age was more pronounced in Mexican Americans (p-value for interaction 0.03), whereas the associations of SCMI with smoking, no-regular exercise, and diabetes were stronger in Whites (p-value for interaction 0.04, 0.001, 0.007, respectively). CONCLUSIONS: Heterogeneity in the racial differences in the prevalence of SCMI risk factors exists, but they do not explain racial differences in SCMI. The stronger associations of smoking, diabetes, and no regular exercise with SCMI partially explain the higher prevalence of SCMI in Whites.


Assuntos
Cardiomiopatias , Eletrocardiografia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Negro ou Afro-Americano/estatística & dados numéricos , Americanos Mexicanos/estatística & dados numéricos , Inquéritos Nutricionais , Prevalência , Fatores de Risco , Estados Unidos/epidemiologia , Brancos , Cardiomiopatias/epidemiologia
13.
Sci Rep ; 14(1): 17479, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39080290

RESUMO

It is known that Copper's (Cu) electrical conductivity makes it a desirable material for use in industry. Due to poor properties such as hardness, thermal expansion, and corrosion resistance, its applications are limited. This manuscript solves these problems while maintaining no breakdown in electrical conductivity. In this study, high-strength ceramics (SiC nanoparticles and graphene nanosheets) were used as reinforcements in the manufacture of Cu-based hybrid nanocomposites using powder metallurgy technique. X-ray diffraction analysis (XRD) was used to investigate phase composition and crystal size of the milled powders. Transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM), respectively examined the microstructure of the prepared powder powders and sintered nanocomposites. Then, various properties of the sintered samples are measured, including physical, electrical and thermal properties and wear resistance. The obtained XRD technique and TEM images showed decreases in the crystal and particle size of milled samples reaching up to 14.08 and 28.30 nm, respectively for the sample contained 8 vol. % SiC + 0.8 vol. % graphene (SG8). A surprising improvement in the mechanical properties of up to 809.15, 341.84 MPa and 336.56 GPa for microhardness, strength and longitudinal modulus for the sample containing the highest reinforcements, achieving an improvement of up to 122, 61.37 and 41 percent compared to the Cu matrix. Moreover, there was a noticeable improvement in the coefficient of thermal expansion (CTE) and wear rate values of the samples by increasing the percentages of hybrid reinforcements in the examined sintered nanocomposite samples. The Sample SG8 recorded the lowest value, decreasing by about 50.2 and 76.5% compared to the SG1 sample. Finally, adding reinforcements to the Cu matrix had a negative effect on the relative density and electrical conductivity, and the lowest values was 92.94% and8.59 × 106 S/m, respectively for the SG sample.

14.
J Clin Med ; 13(6)2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38541807

RESUMO

Background: Although the link between lead exposure and patterns of cardiovascular disease (CVD) has been reported, its association with silent myocardial infarction (SMI) remains unexplored. We aimed to assess the association between blood lead levels (BLLs) and SMI risk. Methods: We included 7283 (mean age 56.1 ± 2.52 years, 52.5% women) participants free of CVD from the Third National Health and Nutrition Examination Survey. BLL was measured using graphite-furnace atomic absorption spectrophotometry. SMI was defined as ECG evidence of myocardial infarction (MI) without history of MI. The association between SMI and BLLs was examined using multivariable logistic regression. Results: SMI was detected in 120 participants with an unweighted prevalence of 1.65%. Higher BLL correlated with higher SMI prevalence across BLL tertiles. In multivariable-adjusted models, participants in the third BLL tertile had more than double the odds of SMI (OR: 3.42, 95%CI: 1.76-6.63) compared to the first tertile. Each 1 µg/dL increase in BLL was linked to a 9% increase in SMI risk. This association was consistent across age, sex, and race subgroups. Conclusions: Higher BLLs are associated with higher odds of SMI in the general population. These results underscore the significance of the ongoing efforts to mitigate lead exposure and implement screening strategies for SMI in high-risk populations.

15.
Sci Rep ; 14(1): 2236, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38278959

RESUMO

Copper (Cu)'s electrical conductivity makes it attractive for industrial usage. Due to its inferior mechanical characteristics, thermal expansion, and wear resistance, its applications are limited. This manuscript solves these issues while retaining its major feature, excellent electrical conductivity. In this regard, different quantities of graphene (Gr) and fly ash (FA) nanoparticles were combined with Cu in a planetary ball mill at 440 rpm for 20 h using powder metallurgy (PM). The microstructure of the generated powders was characterized using X-ray diffraction technique and transmission electron microscopy. The powders underwent compression and were then subjected to firing at three distinct temperature levels, reaching a maximum of 850 °C. In addition, an analysis was conducted on the microstructure, mechanical properties, wear resistance, thermal expansion behaviour, and electrical conductivity of the sintered samples. Based on the findings, the inclusion of a hybrid of Gr and FA ceramics effectively led to a reduction in particle sizes. The bulk density slightly decreases with the addition of hybrid ceramic while increasing with the rise in sintering temperature. The hybrid composited Cu/0.8 vol.% Gr/8 vol.% FA recorded an increase in the microhardness, ultimate stress, and Young's modulus of 25, 20, and 50%, respectively, relative to the Cu matrix. Furthermore, the wear rate and coefficient of thermal expansion for the same sample decreased by 67 and 30%, respectively. Finally, increasing the sintering temperature showed a clear improvement in the mechanical, electrical, and corrosion properties. Based on the results obtained, it can be concluded that the prepared hybrid nanocomposites can be used in power generation, power transmission, electronic circuits, and other applications.

16.
Am J Med Sci ; 368(4): 341-345, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38825075

RESUMO

BACKGROUND: High blood pressure (BP) induces left atrial structural and functional remodeling that increases susceptibility to atrial arrhythmia. We hypothesized that lower systolic BP (SBP) levels are associated with a lower prevalence of premature atrial contractions (PACs) in patients with hypertension. METHODS: This analysis included 4,697 participants (mean age 62±13.1 years, 50% women, 25.6% blacks) with hypertension from the Third National Health and Nutrition Examination Survey who did not have a prior history of cardiovascular disease (CVD). Multivariable logistic regression was used to examine the cross-sectional association between SBP and prevalence of PACs ascertained from 12-lead resting electrocardiograms. Multivariable Cox proportional hazard analysis was used to examine the association between baseline PACs and CVD mortality. RESULTS: Approximately 1.6% (n=74) of participants had baseline PACs. Patients with SBP ≤140 mmHg had a lower prevalence of PACs than those with SBP ≥140 mmHg (1.1% vs. 1.9%, p-value=0.01). In a multivariable logistic regression model, each 10 mmHg decrease in SBP was associated with a 12% lower odds of PACs (OR (95%CI): 0.88 (0.77-0.99)). During 14 years of follow-up, 645 CVD deaths occurred. In a multivariable-adjusted Cox model, presence of PACs was associated with a 78% increased risk of CVD mortality (HR (95%CI): 1.78 (1.23-2.60)). CONCLUSIONS: In patients with hypertension, lower SBP levels are associated with a lower prevalence of PACs, and presence of PACs is associated with a higher risk of CVD mortality risk. These findings highlight the potential role of BP lowering in the management of cardiac arrhythmias.


Assuntos
Complexos Atriais Prematuros , Pressão Sanguínea , Hipertensão , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Hipertensão/fisiopatologia , Hipertensão/epidemiologia , Pressão Sanguínea/fisiologia , Idoso , Complexos Atriais Prematuros/fisiopatologia , Complexos Atriais Prematuros/epidemiologia , Complexos Atriais Prematuros/diagnóstico , Estudos Transversais , Prevalência , Inquéritos Nutricionais
17.
ESMO Open ; 9(6): 103472, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38833972

RESUMO

BACKGROUND: SWItch/Sucrose NonFermentable (SWI/SNF) mutations have garnered increasing attention because of their association with unfavorable prognosis. However, the genetic landscape of SWI/SNF family mutations in Chinese non-small-cell lung cancer (NSCLC) is poorly understood. In addition, the optimal treatment strategy has not yet been determined. PATIENTS AND METHODS: We collected sequencing data on 2027 lung tumor samples from multiple centers in China to comprehensively analyze the genomic characteristics of the SWI/SNF family within the Chinese NSCLC population. Meanwhile, 519 patients with NSCLC from Sun Yat-sen University Cancer Center were enrolled to investigate the potential implications of immunotherapy on patients with SWI/SNF mutations and to identify beneficial subpopulations. We also validated our findings in multiple publicly available cohorts. RESULTS: Approximately 15% of Chinese patients with lung cancer harbored mutations in the SWI/SNF chromatin remodeling complex, which were mutually exclusive to the EGFR mutations. Patients with SWI/SNFmut NSCLC who received first-line chemoimmunotherapy had better survival outcomes than those who received chemotherapy alone (median progression-free survival: 8.70 versus 6.93 months; P = 0.028). This finding was also confirmed by external validation using the POPLAR/OAK cohort. SWI/SNFmut NSCLC is frequently characterized by high tumor mutational burden and concurrent TP53 or STK11/KEAP mutations. Further analysis indicated that TP53 and STK11/KEAP1 mutations could be stratifying factors in facilitating personalized immunotherapy and guiding patient selection. CONCLUSIONS: This study provides a step forward in understanding the genetic and immunological characterization of SWI/SNF genetic alterations. Moreover, our study reveals substantial benefits of immunotherapy over chemotherapy for SWI/SNF-mutant patients, especially the SWI/SNFmut and TP53mut subgroups.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Inibidores de Checkpoint Imunológico , Neoplasias Pulmonares , Mutação , Fatores de Transcrição , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/imunologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia , Masculino , Feminino , Pessoa de Meia-Idade , Fatores de Transcrição/genética , Proteínas Cromossômicas não Histona/genética , Idoso , Proteína SMARCB1/genética , Adulto , Prognóstico , China , DNA Helicases , Proteínas de Ligação a DNA , Proteínas Nucleares
18.
Nan Fang Yi Ke Da Xue Xue Bao ; 43(7): 1224-1232, 2023 Jul 20.
Artigo em Chinês | MEDLINE | ID: mdl-37488805

RESUMO

OBJECTIVE: To propose a diffusion tensor field estimation network based on 3D U-Net and diffusion tensor imaging (DTI) model constraint (3D DTI-Unet) to accurately estimate DTI quantification parameters from a small number of diffusion-weighted (DW) images with a low signal-to-noise ratio. METHODS: The input of 3D DTI-Unet was noisy diffusion magnetic resonance imaging (dMRI) data containing one non-DW image and 6 DW images with different diffusion coding directions. The noise-reduced non-DW image and accurate diffusion tensor field were predicted through 3D U-Net. The dMRI data were reconstructed using the DTI model and compared with the true value of dMRI data to optimize the network and ensure the consistency of the dMRI data with the physical model of the diffusion tensor field. We compared 3D DTI-Unet with two DW image denoising algorithms (MP-PCA and GL-HOSVD) to verify the effect of the proposed method. RESULTS: The proposed method was better than MP-PCA and GL-HOSVD in terms of quantitative results and visual evaluation of DW images, diffusion tensor field and DTI quantification parameters. CONCLUSION: The proposed method can obtain accurate DTI quantification parameters from one non-DW image and 6 DW images to reduce image acquisition time and improve the reliability of quantitative diagnosis.


Assuntos
Imagem de Difusão por Ressonância Magnética , Imagem de Tensor de Difusão , Reprodutibilidade dos Testes , Algoritmos , Razão Sinal-Ruído
19.
Am J Cardiol ; 208: 75-82, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37820550

RESUMO

Albuminuria and left ventricular hypertrophy (LVH) are independent predictors of heart failure (HF); however, to the best of our knowledge, their combined effect on the risk of HF has not yet been explored. Therefore, we examined the joint associations of albuminuria and electrocardiographic-LVH with incident acute decompensated HF (ADHF), and whether albuminuria/LVH combinations modified the effects of blood pressure control strategy in reducing the risk of ADHF. A total of 8,511 participants from the Systolic Blood Pressure Intervention Trial (SPRINT) were included. Electrocardiographic-LVH was present if any of the following criteria were present: Cornell voltage, Cornell voltage product, or Sokolow-Lyon. Albuminuria was defined as urine albumin/creatinine ratio ≥30 mg/g. ADHF was defined as hospitalization or emergency department visit for ADHF. Cox proportional hazard models were used to examine the association of neither LVH nor albuminuria (reference), either LVH or albuminuria, and both (LVH + albuminuria) with incident ADHF. Over a median follow-up of 3.2 years, 182 cases of ADHF occurred. In adjusted models, concomitant albuminuria and LVH were associated with greater risk of ADHF than either albuminuria or LVH in isolation (hazard ratio [95% confidence interval]: 4.95 [3.22 to 7.62], 2.04 [1.39 to 3.00], and 1.47 [0.93 to 2.32], respectively, additive interaction p = 0.01). The effect of intensive blood pressure in reducing ADHF was attenuated in participants with coexisting albuminuria and LVH without any interaction between treatment group assignment and albuminuria/LVH categories (interaction p = 0.26). In conclusion, albuminuria and LVH are additive predictors of ADHF. The effect of intensive blood pressure control in reducing ADHF risk did not vary significantly across albuminuria/LVH combinations.


Assuntos
Insuficiência Cardíaca , Hipertensão , Adulto , Humanos , Hipertrofia Ventricular Esquerda/complicações , Hipertrofia Ventricular Esquerda/epidemiologia , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Pressão Sanguínea/fisiologia , Anti-Hipertensivos/uso terapêutico , Losartan , Albuminúria/epidemiologia , Albuminúria/complicações , Eletrocardiografia , Hipertensão/complicações , Hipertensão/epidemiologia , Hipertensão/tratamento farmacológico , Insuficiência Cardíaca/complicações
20.
medRxiv ; 2023 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-37461491

RESUMO

Background: Albuminuria and left ventricular hypertrophy (LVH) are independent predictors of heart failure (HF), however their combined effect on risk of HF has not been explored previously. Objectives: To examine the joint associations of albuminuria and electrocardiographic (ECG) LVH with incident acute decompensated HF (ADHF), and whether albuminuria/LVH combinations modified the effects of blood pressure control strategy in reducing the risk of ADHF. Methods: 8,511 participants from the SPRINT (Systolic Blood Pressure Intervention Trial) were included. ECG-LVH was present if any of the following criteria: Cornell voltage, Cornell voltage product, or Sokolow Lyon were present. Albuminuria was defined as urine albumin-creatinine ratio (UACR) ≥30 mg/g. ADHF was defined as hospitalization or emergency visit for ADHF. Cox proportional hazard models were used to examine the association of neither LVH, nor albuminuria (reference), either LVH or albuminuria, and both (LVH + albuminuria) with incident ADHF. Results: Over a median follow-up of 3.2 years, 182 cases of ADHF occurred. In adjusted models, concomitant albuminuria and LVH were associated with higher risk of ADHF than either albuminuria or LVH in isolation (HR (95% CI): 4.95 (3.22-7.62), 2.04 (1.39-3.00), and 1.47 (0.93-2.32), respectively (additive interaction p=0.01). The effect of intensive blood pressure in decreasing ADHF attenuated among participants with co-existing albuminuria and LVH without any interaction between treatment group assignment and albuminuria/LVH categories (interaction p-value= 0.26). Conclusions: Albuminuria and LVH are additive predictors of ADHF. The effect of intensive blood pressure control in decreasing ADHF risk did not vary significantly across albuminuria/LVH combinations.

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