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1.
Circulation ; 147(15): 1162-1179, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-36883479

RESUMO

BACKGROUND: Myocardial insulin resistance is a hallmark of diabetic cardiac injury. However, the underlying molecular mechanisms remain unclear. Recent studies demonstrate that the diabetic heart is resistant to other cardioprotective interventions, including adiponectin and preconditioning. The "universal" resistance to multiple therapeutic interventions suggests impairment of the requisite molecule(s) involved in broad prosurvival signaling cascades. Cav (Caveolin) is a scaffolding protein coordinating transmembrane signaling transduction. However, the role of Cav3 in diabetic impairment of cardiac protective signaling and diabetic ischemic heart failure is unknown. METHODS: Wild-type and gene-manipulated mice were fed a normal diet or high-fat diet for 2 to 12 weeks and subjected to myocardial ischemia and reperfusion. Insulin cardioprotection was determined. RESULTS: Compared with the normal diet group, the cardioprotective effect of insulin was significantly blunted as early as 4 weeks of high-fat diet feeding (prediabetes), a time point where expression levels of insulin-signaling molecules remained unchanged. However, Cav3/insulin receptor-ß complex formation was significantly reduced. Among multiple posttranslational modifications altering protein/protein interaction, Cav3 (not insulin receptor-ß) tyrosine nitration is prominent in the prediabetic heart. Treatment of cardiomyocytes with 5-amino-3-(4-morpholinyl)-1,2,3-oxadiazolium chloride reduced the signalsome complex and blocked insulin transmembrane signaling. Mass spectrometry identified Tyr73 as the Cav3 nitration site. Phenylalanine substitution of Tyr73 (Cav3Y73F) abolished 5-amino-3-(4-morpholinyl)-1,2,3-oxadiazolium chloride-induced Cav3 nitration, restored Cav3/insulin receptor-ß complex, and rescued insulin transmembrane signaling. It is most important that adeno-associated virus 9-mediated cardiomyocyte-specific Cav3Y73F reexpression blocked high-fat diet-induced Cav3 nitration, preserved Cav3 signalsome integrity, restored transmembrane signaling, and rescued insulin-protective action against ischemic heart failure. Last, diabetic nitrative modification of Cav3 at Tyr73 also reduced Cav3/AdipoR1 complex formation and blocked adiponectin cardioprotective signaling. CONCLUSIONS: Nitration of Cav3 at Tyr73 and resultant signal complex dissociation results in cardiac insulin/adiponectin resistance in the prediabetic heart, contributing to ischemic heart failure progression. Early interventions preserving Cav3-centered signalsome integrity is an effective novel strategy against diabetic exacerbation of ischemic heart failure.


Assuntos
Insuficiência Cardíaca , Resistência à Insulina , Traumatismo por Reperfusão Miocárdica , Estado Pré-Diabético , Camundongos , Animais , Caveolina 3/genética , Caveolina 3/metabolismo , Adiponectina/metabolismo , Adiponectina/farmacologia , Cloretos/metabolismo , Cloretos/farmacologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/metabolismo
2.
Circ Res ; 131(2): e34-e50, 2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35611695

RESUMO

BACKGROUND: Despite significantly reduced acute myocardial infarction (MI) mortality in recent years, ischemic heart failure continues to escalate. Therapeutic interventions effectively reversing pathological remodeling are an urgent unmet medical need. We recently demonstrated that AdipoR1 (APN [adiponectin] receptor 1) phosphorylation by GRK2 (G-protein-coupled receptor kinase 2) contributes to maladaptive remodeling in the ischemic heart. The current study clarified the underlying mechanisms leading to AdipoR1 phosphorylative desensitization and investigated whether blocking AdipoR1 phosphorylation may restore its protective signaling, reversing post-MI remodeling. METHODS: Specific sites and underlying molecular mechanisms responsible for AdipoR1 phosphorylative desensitization were investigated in vitro (neonatal and adult cardiomyocytes). The effects of AdipoR1 phosphorylation inhibition upon APN post-MI remodeling and heart failure progression were investigated in vivo. RESULTS: Among 4 previously identified sites sensitive to GRK2 phosphorylation, alanine substitution of Ser205 (AdipoR1S205A), but not other 3 sites, rescued GRK2-suppressed AdipoR1 functions, restoring APN-induced cell salvage kinase activation and reducing oxidative cell death. The molecular investigation followed by functional determination demonstrated that AdipoR1 phosphorylation promoted clathrin-dependent (not caveolae) endocytosis and lysosomal-mediated (not proteasome) degradation, reducing AdipoR1 protein level and suppressing AdipoR1-mediated cytoprotective action. GRK2-induced AdipoR1 endocytosis and degradation were blocked by AdipoR1S205A overexpression. Moreover, AdipoR1S205E (pseudophosphorylation) phenocopied GRK2 effects, promoted AdipoR1 endocytosis and degradation, and inhibited AdipoR1 biological function. Most importantly, AdipoR1 function was preserved during heart failure development in AdipoR1-KO (AdipoR1 knockout) mice reexpressing hAdipoR1S205A. APN administration in the failing heart reversed post-MI remodeling and improved cardiac function. However, reexpressing hAdipoR1WT in AdipoR1-KO mice failed to restore APN cardioprotection. CONCLUSIONS: Ser205 is responsible for AdipoR1 phosphorylative desensitization in the failing heart. Blockade of AdipoR1 phosphorylation followed by pharmacological APN administration is a novel therapy effective in reversing post-MI remodeling and mitigating heart failure progression.


Assuntos
Insuficiência Cardíaca , Infarto do Miocárdio , Traumatismo por Reperfusão Miocárdica , Adiponectina/metabolismo , Animais , Insuficiência Cardíaca/metabolismo , Humanos , Isquemia/metabolismo , Camundongos , Camundongos Knockout , Infarto do Miocárdio/patologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , Fosforilação , Receptores de Adiponectina/genética , Receptores de Adiponectina/metabolismo
3.
Circ Res ; 130(1): 48-66, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34763521

RESUMO

BACKGROUND: Patients with acute myocardial infarction suffer systemic metabolic dysfunction via incompletely understood mechanisms. Adipocytes play critical role in metabolic homeostasis. The impact of acute myocardial infarction upon adipocyte function is unclear. Small extracellular vesicles (sEVs) critically contribute to organ-organ communication. Whether and how small extracellular vesicle mediate post-MI cardiomyocyte/adipocyte communication remain unknown. METHODS: Plasma sEVs were isolated from sham control (Pla-sEVSham) or 3 hours after myocardial ischemia/reperfusion (Pla-sEVMI/R) and incubated with adipocytes for 24 hours. Compared with Pla-sEVSham, Pla-sEVMI/R significantly altered expression of genes known to be important in adipocyte function, including a well-known metabolic regulatory/cardioprotective adipokine, APN (adiponectin). Pla-sEVMI/R activated 2 (PERK-CHOP and ATF6 [transcription factor 6]-EDEM [ER degradation enhancing alpha-mannosidase like protein 1] pathways) of the 3 endoplasmic reticulum (ER) stress pathways in adipocytes. These pathological alterations were also observed in adipocytes treated with sEVs isolated from adult cardiomyocytes subjected to in vivo myocardial ischemia/reperfusion (MI/R) (Myo-sEVMI/R). Bioinformatic/RT-qPCR analysis demonstrates that the members of miR-23-27-24 cluster are significantly increased in Pla-sEVMI/R, Myo-sEVMI/R, and adipose tissue of MI/R animals. Administration of cardiomyocyte-specific miR-23-27-24 sponges abolished adipocyte miR-23-27-24 elevation in MI/R animals, supporting the cardiomyocyte origin of adipocyte miR-23-27-24 cluster. In similar fashion to Myo-sEVMI/R, a miR-27a mimic activated PERK-CHOP and ATF6-EDEM-mediated ER stress. Conversely, a miR-27a inhibitor significantly attenuated Myo-sEVMI/R-induced ER stress and restored APN production. RESULTS: An unbiased approach identified EDEM3 (ER degradation enhancing alpha-mannosidase like protein 3) as a novel downstream target of miR-27a. Adipocyte EDEM3 deficiency phenocopied multiple pathological alterations caused by Myo-sEVMI/R, whereas EDEM3 overexpression attenuated Myo-sEVMI/R-resulted ER stress. Finally, administration of GW4869 or cardiomyocyte-specific miR-23-27-24 cluster sponges attenuated adipocyte ER stress, improved adipocyte endocrine function, and restored plasma APN levels in MI/R animals. CONCLUSIONS: We demonstrate for the first time that MI/R causes significant adipocyte ER stress and endocrine dysfunction by releasing miR-23-27-24 cluster-enriched small extracellular vesicle. Targeting small extracellular vesicle-mediated cardiomyocyte-adipocyte pathological communication may be of therapeutic potential to prevent metabolic dysfunction after MI/R.


Assuntos
Adipócitos/metabolismo , Comunicação Celular , Estresse do Retículo Endoplasmático , Vesículas Extracelulares/metabolismo , Infarto do Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Fator 6 Ativador da Transcrição/metabolismo , Adiponectina/metabolismo , Animais , Masculino , Proteínas de Membrana/metabolismo , Camundongos , MicroRNAs/metabolismo , Fator de Transcrição CHOP/metabolismo , eIF-2 Quinase/metabolismo
4.
Arterioscler Thromb Vasc Biol ; 43(12): e491-e508, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37795615

RESUMO

BACKGROUND: APN (adiponectin) and APPL1 (adaptor protein, phosphotyrosine interacting with PH domain and leucine zipper 1) are potent vasculoprotective molecules, and their deficiency (eg, hypoadiponectinemia) contributes to diabetic vascular complications. However, the molecular mechanisms that govern their vasculoprotective genes as well as their alteration by diabetes remain unknown. METHODS: Diabetic medium-cultured rat aortic endothelial cells, mouse aortic endothelial cells from high-fat-diet animals, and diabetic human aortic endothelial cells were used for molecular/cellular investigations. The in vivo concept-prove demonstration was conducted using diabetic vascular injury and diabetic hindlimb ischemia models. RESULTS: In vivo animal experiments showed that APN replenishment caused APPL1 nuclear translocation, resulting in an interaction with HDAC (histone deacetylase) 2, which inhibited HDAC2 activity and increased H3Kac27 levels. Based on transcriptionome pathway-specific real-time polymerase chain reaction profiling and bioinformatics analysis, Angpt1 (angiopoietin 1), Ocln (occludin), and Cav1 (caveolin 1) were found to be the top 3 vasculoprotective genes suppressed by diabetes and rescued by APN in an APPL1-dependent manner. APN reverses diabetes-induced inhibition of Cav1 interaction with APPL1. APN-induced Cav1 expression was not affected by Angpt1 or Ocln deficiency, whereas APN-induced APPL1 nuclear translocation or upregulation of Angpt1/Ocln expression was abolished in the absence of Cav1 both in vivo and in vitro, suggesting Cav1 is upstream molecule of Angpt1/Ocln in response to APN administration. Chromatin immunoprecipitation-qPCR (quantitative polymerase chain reaction) demonstrated that APN caused significant enrichment of H3K27ac in Angpt1 and Ocln promoter region, an effect blocked by APPL1/Cav1 knockdown or HDAC2 overexpression. The protective effects of APN on the vascular system were attenuated by overexpression of HDAC2 and abolished by knocking out APPL1 or Cav1. The double knockdown of ANGPT1/OCLN blunted APN vascular protection both in vitro and in vivo. Furthermore, in diabetic human endothelial cells, HDAC2 activity is increased, H3 acetylation is decreased, and ANGPT1/OCLN expression is reduced, suggesting that the findings have important translational implications. CONCLUSIONS: Hypoadiponectinemia and dysregulation of APPL1-mediated epigenetic regulation are novel mechanisms leading to diabetes-induced suppression of vasculoprotective gene expression. Diabetes-induced pathological vascular remodeling may be prevented by interventions promoting APPL1 nuclear translocation and inhibiting HDAC2.


Assuntos
Diabetes Mellitus , Angiopatias Diabéticas , Lesões do Sistema Vascular , Animais , Humanos , Camundongos , Ratos , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adiponectina/metabolismo , Diabetes Mellitus/genética , Angiopatias Diabéticas/genética , Angiopatias Diabéticas/prevenção & controle , Angiopatias Diabéticas/metabolismo , Células Endoteliais/metabolismo , Epigênese Genética , Lesões do Sistema Vascular/genética
5.
Artigo em Inglês | MEDLINE | ID: mdl-38818580

RESUMO

Fibroblast growth factor (FGF) isoform 13, a distinct type of FGF, boasts significant potential for therapeutic intervention in cardiovascular dysfunctions. However, its impact on regulating fibrosis remains unexplored. This study aims to elucidate the role and mechanism of FGF13 on cardiac fibrosis. Here, we show that following transverse aortic constriction (TAC) surgery, interstitial fibrosis and collagen content increase in mice, along with reduced ejection fraction and fractional shortening, augmented heart mass. However, following Fgf13 deletion, interstitial fibrosis is decreased, ejection fraction and fractional shortening are increased, and heart mass is decreased, compared with those in the TAC group. Mechanistically, incubation of cardiac fibroblasts with transforming growth factor ß (TGFß) increases the expressions of types I and III collagen proteins, as well as α-smooth muscle actin (α-SMA) proteins, and enhances fibroblast proliferation and migration. In the absence of Fgf13, the expressions of these proteins are decreased, and fibroblast proliferation and migration are suppressed, compared with those in the TGFß-stimulated group. Overexpression of FGF13, but not FGF13 mutants defective in microtubule binding and stabilization, rescues the decrease in collagen and α-SMA protein and weakens the proliferation and migration function of the Fgf13 knockdown group. Furthermore, Fgf13 knockdown decreases ROCK protein expression via microtubule disruption. Collectively, cardiac Fgf13 knockdown protects the heart from fibrosis in response to haemodynamic stress by modulating microtubule stabilization and ROCK signaling pathway.

6.
BMC Cardiovasc Disord ; 23(1): 323, 2023 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-37355592

RESUMO

BACKGROUND: Hydration is currently the main measure to prevent contrast-induced nephropathy (CIN). We aimed to compare the preventive effect of preprocedure and postprocedure hydration on CIN in patients with coronary heart disease undergoing elective percutaneous coronary intervention (PCI). METHODS: A retrospective study included 198 cases of postprocedure hydration and 396 cases of preprocedure hydration using propensity score matching. The incidence of CIN 48 h after PCI and adverse events within 30 days after contrast media exposure were compared between the two groups. Logistic regression analysis was used to analyse the risk factors for CIN. RESULTS: The incidence of CIN in the postprocedure hydration group was 3.54%, while that in the preprocedure hydration group was 4.8%. There was no significant difference between the two groups (p = 0.478). Multivariate logistic regression analysis showed that diabetes mellitus, baseline BNP and cystatin C levels, and contrast agent dosage were independent risk factors for CIN. There was no significant difference in the incidence of major adverse events between the two groups (3.03% vs. 2.02%, p = 0.830). CONCLUSIONS: Postprocedure hydration is equally effective compared to preoperative hydration in the prevention of CIN in patients with coronary heart disease undergoing elective PCI.


Assuntos
Doença das Coronárias , Nefropatias , Intervenção Coronária Percutânea , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Estudos Retrospectivos , Meios de Contraste/efeitos adversos , Nefropatias/induzido quimicamente , Nefropatias/diagnóstico , Nefropatias/epidemiologia , Doença das Coronárias/etiologia
7.
J Opt Soc Am A Opt Image Sci Vis ; 40(9): 1724-1732, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37707009

RESUMO

The camera function of a smartphone can be used to quantitatively detect urine parameters anytime, anywhere. However, the color captured by different cameras in different environments is different. A method for color correction is proposed for a urine test strip image collected using a smartphone. In this method, the color correction model is based on the color information of the urine test strip, as well as the ambient light and camera parameters. Conv-TabNet, which can focus on each feature parameter, was designed to correct the color of the color blocks of the urine test strip. The color correction experiment was carried out in eight light sources on four mobile phones. The experimental results show that the mean absolute error of the new method is as low as 2.8±1.8, and the CIEDE2000 color difference is 1.5±1.5. The corrected color is almost consistent with the standard color by visual evaluation. This method can provide a technology for the quantitative detection of urine test strips anytime and anywhere.

8.
J Electrocardiol ; 81: 176-185, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37741272

RESUMO

PURPOSE: The current study was conducted to investigate the electrocardiographic (ECG) characteristics of idiopathic premature ventricular contractions (PVCs) originating from the aortic sinus cusp (ASC) and establish a novel ECG criterion to discriminate PVCs originating from the right coronary cusp (RCC), left coronary cusp (LCC), and the left and right coronary cusp junction (LRJ). METHODS: A retrospective analysis was performed on a total of 133 patients with idiopathic PVCs who underwent successful mapping and ablation. The sites of origin (SOO) were confirmed using fluoroscopy and a three-dimensional mapping system during radiofrequency catheter ablation (RFCA). Among the patients, 69 had PVCs originating from the LCC, 39 from the RCC, and 25 from the LRJ. Characteristics of surface 12­lead electrocardiograms (ECGs) recorded during PVCs were analyzed. Q-, R-, S, and R'-wave amplitudes were measured in lead I, and the lead I R-wave indexes (IRa, IRb, IRc, IRd, and IRe) were derived by employing multiplication, subtraction, sum, and division operations on these ECG measurements. Notably, IRb and IRe demonstrated usefulness as ECG indexes for discriminating PVCs originating from RCC, LCC, and LRJ in the ASC. RESULTS: The R- and S-wave amplitudes in lead I exhibited statistically significant differences among the three groups (P < 0.001 and P < 0.001, respectively). In discriminating PVCs originating from the RCC from the other two groups, IRb showed the largest area under the curve (AUC) of 0.813, as assessed by receiver operating characteristic (ROC) analysis, with a cutoff value of ≤0.5 indicating PVCs of RCC origin. The sensitivity and specificity were 80.3% and 78.7%, respectively. For discriminating PVCs arising from the LCC from those in the LRJ group, IRe exhibited the largest AUC of 0.801, with an optimal cutoff value of 0. An IRe value >0 indicated PVCs originating from the LRJ, while an IRe value ≤0 indicated PVCs originating from the LCC. The sensitivity and specificity of the IRe index were 84.0% and 70.7%, respectively. CONCLUSION: Lead I R-wave indexes provided simple and useful ECG criteria for discriminating PVCs originating from the LCC, RCC, and LRJ in the left ventricular outflow tract (LVOT).


Assuntos
Carcinoma de Células Renais , Ablação por Cateter , Neoplasias Renais , Seio Aórtico , Taquicardia Ventricular , Complexos Ventriculares Prematuros , Humanos , Estudos Retrospectivos , Seio Aórtico/cirurgia , Carcinoma de Células Renais/cirurgia , Eletrocardiografia/métodos , Ablação por Cateter/métodos , Neoplasias Renais/cirurgia
9.
Ren Fail ; 44(1): 1486-1497, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36000917

RESUMO

BACKGROUND: Patients with acute decompensated heart failure (ADHF) show cardiorenal syndrome type 1 (CRS-1) are more likely to have a poor outcome. However, the current criteria often lead to delayed CRS-1 diagnosis. Therefore, we evaluated the predictive value of plasma proenkephalin (pPENK) and urine NT-proBNP (uNT-proBNP) for early diagnosis of CRS-1 and vulnerable-phase prognosis in ADHF patients. METHODS: The plasma NT-proBNP (pNT-proBNP), pPENK, and uNT-proBNP were measured in 121 ADHF patients on admission. The plasma neutrophil gelatinase-associated lipocalin (pNGAL) was chosen as the reference. Logistic regression was used to determine the predictors of CRS-1. The area under the receiver operating curves (ROCs) was calculated to assess the early diagnostic value of pNGAL, pPENK, and uNT-proBNP/uCr for CRS-1. To evaluate the prognostic risk of factors for the 90-d outcomes of all ADHF patients, the Cox regression was performed and the cumulative risk curve was plotted. RESULTS: We found that pPENK [OR 1.093 (95% CI 1.022-1.169), p = 0.010; AUROC = 0.899 (95% CI 0.831-0.946)] and uNT-proBNP/uCr ratio [OR 1.015 (95% CI 1.003-1.028), p = 0.012; AUROC = 0.934 (95% CI 0.874-0.971)] could independently predict the occurrence of CRS-1 in hospitalized patients with ADHF. The pPENK [HR 1.014 (95% CI 1.000-1.042), p = 0.044] and uNT-proBNP/uCr ration [HR 0.998 (95% CI 0.997-1.000), p = 0.045] were also independent predictors of the risk of HF readmission or all-cause death 90 d after discharge in ADHF patients. CONCLUSIONS: The newly found pPENK and noninvasive test of uNT-proBNP/uCr ratio (pg/nmol) on admission may be two promising novel predictive biomarkers for early diagnosis of CRS-1 occurrence and vulnerable-phase outcomes in ADHF patients.


Assuntos
Síndrome Cardiorrenal , Insuficiência Cardíaca , Biomarcadores , Síndrome Cardiorrenal/diagnóstico , Diagnóstico Precoce , Encefalinas , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico , Humanos , Peptídeo Natriurético Encefálico , Fragmentos de Peptídeos , Prognóstico , Estudos Prospectivos , Precursores de Proteínas
10.
Int J Nurs Pract ; 28(2): e12916, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33491291

RESUMO

AIM: This study aimed to investigate the effect of different probe placements on the ventral and dorsal sides of the same finger using pulse oxygen saturation monitoring. METHODS: This clinical trial used a convenience sampling method in patients admitted to the Second Hospital of Hebei Medical University. We enrolled 1330 patients from March to July 2018, including patients who were hospitalized in the intensive care unit (n = 258) and in the general ward (n = 1072). Pulse oxygen saturation measurements obtained from the ventral and dorsal sides of the same finger were compared. This work adhered to the STROBE checklist requirements. RESULTS: We found that pulse oxygen saturation measurements between the dorsal and ventral sides of a finger were not affected by different fingers, disease types, the application of a ventilator, vasoactive drugs, the conscious state of the patient or the instrument model. CONCLUSION: Our findings suggested no significant difference in saturation measurements with variation in the placement of the pulse oxygen saturation measurement instrument between the dorsal and ventral sides of a finger, regardless of illness severity. We believe that these results could simplify the monitoring procedures performed by nurses and eliminate worries concerning the inaccuracy of data because of varied probe positions.


Assuntos
Oximetria , Saturação de Oxigênio , Dedos , Humanos , Unidades de Terapia Intensiva , Monitorização Fisiológica , Oximetria/métodos
11.
Entropy (Basel) ; 24(5)2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35626514

RESUMO

In this paper, three iterative methods (Stokes, Newton and Oseen iterative methods) based on finite element discretization for the stationary micropolar fluid equations are proposed, analyzed and compared. The stability and error estimation for the Stokes and Newton iterative methods are obtained under the strong uniqueness conditions. In addition, the stability and error estimation for the Oseen iterative method are derived under the uniqueness condition of the weak solution. Finally, numerical examples test the applicability and the effectiveness of the three iterative methods.

12.
Entropy (Basel) ; 24(4)2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35455117

RESUMO

In this paper, four stabilized methods based on the lowest equal-order finite element pair for the steady micropolar Navier-Stokes equations (MNSE) are presented, which are penalty, regular, multiscale enrichment, and local Gauss integration methods. A priori properties, existence, uniqueness, stability, and error estimation based on Fem approximation of all the methods are proven for the physical variables. Finally, some numerical examples are displayed to show the numerical characteristics of these methods.

13.
BMC Cardiovasc Disord ; 21(1): 474, 2021 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-34600490

RESUMO

BACKGROUND: Recent evidence has shown that the pathogenesis of ischaemic stroke associated with atrial fibrillation (AF) is complex and involves other factors in addition to arrhythmias. The purpose of this study was to investigate the relationship among AF, CHA2DS2-VASc score and ischaemic stroke in patients with coronary artery disease (CAD) in Hebei, China. METHODS: A total of 2,335 patients with CAD from September 2016 to May 2019 at the Second Hospital of Hebei Medical University were included (mean age 62.73 ± 10.35 years, range 26-92 years; 41.58% female). This was a cross-sectional study, and participants were divided into non-stroke (n = 1997) and ischaemic stroke groups (n = 338). Propensity score matching (PSM) was performed to match ischaemic stroke patients with non-stroke patients in a 1:4 ratio. The relationship among AF, the CHA2DS2-VASc score and ischaemic stroke was evaluated using univariable generalized linear models for different sex, age, body mass index (BMI), CAD and CHA2DS2-VASc score subgroups. Univariable and multivariable generalized linear models were used to evaluate the relationship between AF and ischaemic stroke in the different models. RESULTS: Compared with that in the non-stroke group, the prevalence of AF (8.81% vs. 14.20%, P = 0.002) in the ischaemic stroke group was higher. The proportion of patients with ischaemic stroke was significantly different between the AF group and the non-AF group (28.74% vs. 19.04%, P = 0.003). An increasing CHA2DS2-VASc score was associated with a gradual increase in the prevalence of AF (P for trend < 0.001). Subgroup analysis showed that the trend towards increased stroke risk in the AF group was consistent across the various subgroups. The multivariable analysis demonstrated that AF was not associated with ischaemic stroke compared with the absence of AF (OR = 1.55, 95% CI 0.94-2.56, P = 0.087). CONCLUSION: In our cross-sectional study, after adjustment for confounding factors, there was no association between AF and ischaemic stroke. The increased risk of ischaemic stroke associated with AF was attenuated by atherosclerotic factors. Our study supports the current view that enhanced control of modifiable cardiovascular risk factors in patients with AF is essential.


Assuntos
Fibrilação Atrial/epidemiologia , Doença da Artéria Coronariana/epidemiologia , Técnicas de Apoio para a Decisão , AVC Isquêmico/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/diagnóstico , China/epidemiologia , Doença da Artéria Coronariana/diagnóstico , Estudos Transversais , Feminino , Humanos , AVC Isquêmico/diagnóstico , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prevalência , Prognóstico , Pontuação de Propensão , Medição de Risco , Fatores de Risco
14.
Ann Noninvasive Electrocardiol ; 26(4): e12832, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33620147

RESUMO

BACKGROUD: Present electrocardiogram (ECG) criteria for diagnosing left ventricular hypertrophy (LVH) usually have low sensitivity, while the newly proposed SD + SV4 criterion, namely the deepest S-wave amplitude in any lead (SD) plus SV4 amplitude, has been reported to have higher sensitivity and accuracy compared with other existing criteria. We aimed to further evaluate the diagnostic value of the SD + SV4 criterion in reference to the gold standard cardiac magnetic resonance imaging (CMR) in LVH diagnosis. METHODS: This retrospective study enrolled 138 patients who received CMR examination-60 patients with reduced ejection fraction (EF) and 78 patients with preserved EF. The left ventricular mass index (LVMI) measured by CMR was used as the gold standard for diagnosing LVH. RESULT: The diagnostic value of the SD + SV4 criterion was compared with other 4 commonly used criteria. By CMR, 29 out of 138 people (21%) were diagnosed with LVH in reference to CMR. The SD + SV4 criterion had markedly higher sensitivity in diagnosing LVH compared with other criteria, but no higher specificity. There was no significant difference in area under receiver operating characteristic (ROC) curve among these criteria. The SD + SV4 criterion was not markedly consistent with CMR in diagnosing LVH. Compared to the other criteria, the SD + SV4 criterion had the highest sensitivity in patients with reduced ejection fraction; however, the area under the curve (AUC) of the SD + SV4 criterion in patients with reduced EF was significantly lower than in patients with preserved EF. CONCLUSION: The newly proposed SD + SV4 criterion did not have a better diagnostic value compared with other existing criteria, and the statistical power of the SD + SV4 criterion was influenced by EF.


Assuntos
Eletrocardiografia , Hipertrofia Ventricular Esquerda , Coração , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Sensibilidade e Especificidade
15.
Intern Med J ; 51(12): 2087-2094, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32975880

RESUMO

BACKGROUND: It is recommended that blood pressure should be measured on a bare upper arm with an appropriately sized cuff. However, in practice, it is more convenient to measure blood pressure on sleeved arms. AIMS: We aim to examine the effect of sleeved arms on the accuracy of blood pressure measurement. METHODS: Patients aged 18 years or older were enrolled. Participants underwent three blood pressure measurements in each of the following sleeve conditions in random order (bare arm; arm covered with a single-layer cotton shirt sleeve,1 mm; arm covered with two layers sleeve containing a cotton shirt and a polar fabric sweater, 3 mm; arm covered with two layers sleeve containing a cotton shirt and a thick cardigan, 4 mm). RESULTS: Of the 300 participants, 155 (52%) were men. The mean age was 62.9 (10.7) years, and 226 (75%) had hypertension. There were no significant differences in either systolic blood pressure or diastolic blood pressure among the four kinds of sleeve conditions in all the participants (P > 0.5), and the mean blood pressure differences between measurements made on the sleeved arms and bare arm were within 1.0 mmHg. Blood pressure of sleeved arms was positively correlated with that of the bare arm (P < 0.001; r > 0.95), and showed good consistency. CONCLUSIONS: In the present study, we concluded that there was no significant effect of sleeved arms on the accuracy of blood pressure measurement by using an electronic oscillometric sphygmomanometer equipped with a conventional cuff.


Assuntos
Braço , Hipertensão , Adolescente , Braço/fisiologia , Pressão Sanguínea , Determinação da Pressão Arterial , Vestuário , Humanos , Hipertensão/diagnóstico , Masculino , Pessoa de Meia-Idade
16.
Transfus Med Hemother ; 47(2): 110-118, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32355470

RESUMO

BACKGROUND: Platelet activation occurs upon ischemia/reperfusion and is related to the generation of reactive oxygen species (ROS) during this process. Vitamin C (VC) is a powerful antioxidant. VC scavenges ROS, reduces platelet activation, and attenuates reperfusion injury. However, the effects of VC on platelets undergoing hypoxia/reoxygenation (H/R) remain unclear. OBJECTIVES: Herein, we evaluated the effects of VC on platelets in vitro following H/R and the related mechanisms. METHOD: Fresh platelets were collected from 67 volunteers at the Blood Center of Hebei Province. Platelets were diluted with saline to a concentration of 2.00 × 1011/L. Aggregation and the curve slope were evaluated within 4 h with a whole-blood impedance analyzer. To determine the optimal experimental time, platelets were treated with hypoxia or reoxygenation for different times, and impedance aggregometry was carried out by measuring changes in electrical impedance induced by arachidonic acid (0.5 mM) and adenosine diphosphate (10 µM), thereby establishing the H/R model. Three antioxidants (VC, melatonin, and probucol) were used to treat platelets after H/R, and impedance aggregometry was used to determine their effects on platelet aggregation. The influence of VC on apoptosis-related indicators was detected. ROS and the mitochondrial membrane potential were observed by inverted fluorescence microscopy and flow cytometry, respectively. Related protein levels were detected by Western blotting. RESULTS: ROS scavengers inhibited platelet activation and aggregation in a concentration-dependent manner. VC post-conditioning scavenged ROS, downregulated cytochrome C, Bax, and caspase-9 proteins, and upregulated Bcl-2 protein. These effects collectively blocked platelet apoptosis and inhibited platelet aggregation. CONCLUSIONS: VC inhibited platelet aggregation by blocking apoptosis. Thus, VC may have applications in the treatment of platelet-related diseases.

17.
BMC Cardiovasc Disord ; 19(1): 152, 2019 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-31234798

RESUMO

BACKGROUND: Contrast-induced nephropathy (CIN) is common after percutaneous coronary intervention (PCI) and always leads to a poor prognosis. Compared with conventional detection methods, either high-sensitivity C-reactive protein (hs-CRP) or procalcitonin have higher sensitivity and specificity for predicting CIN, but their combination has not been explored. This prospective study investigated the value of hs-CRP combined with procalcitonin for predicting CIN after PCI. METHODS: All patients undergoing PCI admitted to our hospital during the year 2016 were consecutively enrolled (n = 343). The patients received adequate hydration before PCI and 20 mg furosemide after the procedure. CIN was diagnosed by a 25% elevation in serum creatinine or ≥ 44.2 µmol/L (0.5 mg/dL) serum creatinine within 48 to 72 h after intravenous injection of contrast media. RESULTS: Patients with high hs-CRP or procalcitonin had higher rates of CIN relative to those patients with low values. For predicting CIN, hs-CRP combined with procalcitonin showed an area under the receiver operating characteristic curve of 0.67, with optimal cut-off value 0.0643610, and the sensitivity and specificity were higher than hs-CRP or procalcitonin alone. The logistic regression analysis showed that high-risk factors of CIN were acute myocardial infarction and highly elevated hsCRP and procalcitonin. CONCLUSIONS: Prior to PCI, an elevation of the inflammatory biomarkers hsCRP and procalcitonin are a risk factor for postoperative CIN. This study suggests that the combination of hsCRP and procalcitonin is a better predictor of CIN after PCI then either hsCRP or procalcitonin alone. TRIAL REGISTRATION NUMBER: ChiCTR-IOR-14005250. Date of registration 2014-09-24.


Assuntos
Proteína C-Reativa/metabolismo , Meios de Contraste/efeitos adversos , Doença da Artéria Coronariana/terapia , Nefropatias/induzido quimicamente , Intervenção Coronária Percutânea/efeitos adversos , Pró-Calcitonina/sangue , Idoso , Biomarcadores/sangue , Meios de Contraste/administração & dosagem , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico , Creatinina/sangue , Feminino , Hidratação , Furosemida/administração & dosagem , Humanos , Injeções Intravenosas , Nefropatias/sangue , Nefropatias/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Inibidores de Simportadores de Cloreto de Sódio e Potássio/administração & dosagem , Fatores de Tempo , Resultado do Tratamento , Regulação para Cima
18.
Small ; 11(32): 3962-72, 2015 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-25963931

RESUMO

Three half-sandwich iridium and ruthenium organometallic complexes with high cytotoxicity are synthesized, and their anticancer mechanisms are elucidated. The organometallic complexes can interact with DNA through coordination or intercalation, thereby inducing apoptosis and inhibiting proliferation of resistant cancer cells. The organometallic complexes are then incorporated into polymeric micelles through the polymer-metal coordination between poly(ethylene glycol)-b-poly(glutamic acid) [PEG-b-P(Glu)] and organometallic complexes to further enhance their anticancer effects as a result of the enhanced permeability and retention effect. The micelles with particle sizes of ≈60 nm are more efficiently internalized by cancer cells than the corresponding complexes, and selectively dissociate and release organometallic anticancer agents within late endosomes and lysosomes, thereby enhancing drug delivery to the nuclei of cancer cells and facilitating their interactions with DNA. Thus, the micelles display higher antitumor activity than the organometallic complexes alone with a lack of the systemic toxicity in a mouse xenograft model of cisplatin-resistant human ovarian cancer. These results suggest that the polymeric micelles carrying anticancer organometallic complexes provide a promising platform for the treatment of resistant ovarian cancer and other hard-to-treat solid tumors.


Assuntos
DNA/metabolismo , Resistencia a Medicamentos Antineoplásicos , Micelas , Compostos Organometálicos/química , Neoplasias Ovarianas/tratamento farmacológico , Polímeros/química , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Peso Corporal/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Humanos , Concentração Inibidora 50 , Camundongos Nus , Compostos Organometálicos/síntese química , Neoplasias Ovarianas/patologia
19.
J Am Chem Soc ; 136(14): 5181-4, 2014 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-24669930

RESUMO

Ovarian cancer is the leading cause of death among women with gynecological malignancies. Acquired resistance to chemotherapy is a major limitation for ovarian cancer treatment. We report here the first use of nanoscale metal-organic frameworks (NMOFs) for the co-delivery of cisplatin and pooled small interfering RNAs (siRNAs) to enhance therapeutic efficacy by silencing multiple drug resistance (MDR) genes and resensitizing resistant ovarian cancer cells to cisplatin treatment. UiO NMOFs with hexagonal-plate morphologies were loaded with a cisplatin prodrug and MDR gene-silencing siRNAs (Bcl-2, P-glycoprotein [P-gp], and survivin) via encapsulation and surface coordination, respectively. NMOFs protect siRNAs from nuclease degradation, enhance siRNA cellular uptake, and promote siRNA escape from endosomes to silence MDR genes in cisplatin-resistant ovarian cancer cells. Co-delivery of cisplatin and siRNAs with NMOFs led to an order of magnitude enhancement in chemotherapeutic efficacy in vitro, as indicated by cell viability assay, DNA laddering, and Annexin V staining. This work shows that NMOFs hold great promise in the co-delivery of multiple therapeutics for effective treatment of drug-resistant cancers.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Nanoestruturas/química , Compostos Organometálicos/química , Neoplasias Ovarianas/tratamento farmacológico , RNA Interferente Pequeno/farmacologia , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/administração & dosagem , Cisplatino/química , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Humanos , Nanoestruturas/administração & dosagem , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Tamanho da Partícula , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/química , Propriedades de Superfície
20.
Cell Physiol Biochem ; 33(1): 129-41, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24481040

RESUMO

BACKGROUND: Arterial calcification is a major event in the progression of atherosclerosis. It is reported that statins exhibit various protective effects against vascular smooth muscle cell (VSMC) inflammation and proliferation in cardiovascular remodeling. Although statins counteract atherosclerosis, the molecular mechanisms of statins on the calcium release from VSMCs have not been clearly elucidated. METHODS: Calcium content of VSMCs was measured using enzyme-linked immunosorbent assay (ELISA). The expression of proteins involved in cellular transdifferentiation was analyzed by western blot. Cell autophagy was measured by fluorescence microscopic analysis for acridine orange staining and transmission electron microscopy analysis. The autophagic inhibitors (3-MA, chloroquine, NH4Cl and bafilomycin A1) and ß-catenin inhibitor JW74 were used to assess the effects of atorvastatin on autophagy and the involvement of ß-catenin on cell calcification respectively. Furthermore, cell transfection was performed to overexpress ß-catenin. RESULTS: In VSMCs, atorvastatin significantly suppressed transforming growth factor-ß1 (TGF-ß1)-stimulated calcification, accompanied by the induction of autophagy. Downregulation of autophagy with autophagic inhibitors significantly suppressed the inhibitory effect of atorvastatin on cell calcification. Moreover, the beneficial effect of atorvastatin on calcification and autophagy was reversed by ß-catenin overexpression. Conversely, JW74 supplement enhanced this effect. CONCLUSION: These data demonstrated that atorvastatin protect VSMC from TGF-ß1-stimulated calcification by inducing autophagy through suppression of the ß-catenin pathway, identifying autophagy induction might be a therapeutic strategy for use in vascular calcification.


Assuntos
Atorvastatina/farmacologia , Autofagia/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/patologia , Fator de Crescimento Transformador beta1/farmacologia , Calcificação Vascular/patologia , beta Catenina/metabolismo , Animais , Regulação para Baixo/efeitos dos fármacos , Masculino , Modelos Biológicos , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/ultraestrutura , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
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