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1.
Small ; : e2402841, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693072

RESUMO

Developing lightweight composite with reversible switching between microwave (MW) absorption and electromagnetic interference (EMI) shielding is promising yet remains highly challenging due to the completely inconsistent attenuation mechanism for electromagnetic (EM) radiation. Here, a lightweight vanadium dioxide/expanded polymer microsphere composites foam (VO2/EPM) is designed and fabricated with porous structures and 3D VO2 interconnection, which possesses reversible switching function between MW absorption and EMI shielding under thermal stimulation. The VO2/EPM exhibits MW absorption with a broad effective absorption bandwidth of 3.25 GHz at room temperature (25 °C), while provides EMI shielding of 23.1 dB at moderately high temperature (100 °C). This reversible switching performance relies on the porous structure and tunability of electrical conductivity, complex permittivity, and impedance matching, which are substantially induced by the convertible crystal structure and electronic structure of VO2. Finite element simulation is employed to qualitatively investigate the change in interaction between EM waves and VO2/EPM before and after the phase transition. Moreover, the application of VO2/EPM is demonstrated with a reversible switching function in controlling wireless transmission on/off, showcasing its excellent cycling stability. This kind of smart material with a reversible switching function shows great potential in next-generation electronic devices.

2.
Nanomicro Lett ; 16(1): 134, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38411757

RESUMO

The remarkable properties of carbon nanotubes (CNTs) have led to promising applications in the field of electromagnetic interference (EMI) shielding. However, for macroscopic CNT assemblies, such as CNT film, achieving high electrical and mechanical properties remains challenging, which heavily depends on the tube-tube interactions of CNTs. Herein, we develop a novel strategy based on metal-organic decomposition (MOD) to fabricate a flexible silver-carbon nanotube (Ag-CNT) film. The Ag particles are introduced in situ into the CNT film through annealing of MOD, leading to enhanced tube-tube interactions. As a result, the electrical conductivity of Ag-CNT film is up to 6.82 × 105 S m-1, and the EMI shielding effectiveness of Ag-CNT film with a thickness of ~ 7.8 µm exceeds 66 dB in the ultra-broad frequency range (3-40 GHz). The tensile strength and Young's modulus of Ag-CNT film increase from 30.09 ± 3.14 to 76.06 ± 6.20 MPa (~ 253%) and from 1.12 ± 0.33 to 8.90 ± 0.97 GPa (~ 795%), respectively. Moreover, the Ag-CNT film exhibits excellent near-field shielding performance, which can effectively block wireless transmission. This innovative approach provides an effective route to further apply macroscopic CNT assemblies to future portable and wearable electronic devices.

4.
Small Methods ; 7(4): e2201694, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36802141

RESUMO

MXenes with unique physicochemical properties have shown substantial potential in electromagnetic interference (EMI) shielding. However, the chemical instability and mechanical fragility of MXenes has become a major hurdle for their application. Abundant strategies have been dedicated to improving the oxidation stability of colloidal solution or mechanical properties of films, which always come at the expense of electrical conductivity and chemical compatibility. Here, hydrogen bond (H-bond) and coordination bond are employed to achieve chemical and colloidal stability of MXenes (0.1 mg mL-1 ) by occupying the reaction sites of Ti3 C2 Tx attacking of water and oxygen molecules. Compared to the Ti3 C2 Tx , the Ti3 C2 Tx modified with alanine via H-bond shows significantly improved oxidation stability (at room temperature over 35 days), while the Ti3 C2 Tx modified with cysteine by synergy of H-bond and coordination bond can be maintained even after 120 days. Simulation and experimental results verify the formation of H-bond and Ti-S bond by a Lewis acid-base interaction between Ti3 C2 Tx and cysteine. Furthermore, the synergy strategy significantly improves the mechanical strength of the assembled film (up to 78.1 ± 7.9 MPa), corresponding the increment of 203% compared to untreated one, almost without compromising the electrical conductivity and EMI shielding performance.

5.
ACS Appl Mater Interfaces ; 14(2): 3302-3314, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-34991311

RESUMO

Highly conductive polymer foam with light weight, flexibility, and high-performance electromagnetic interference (EMI) shielding is highly desired in the fields of aerospace, communication, and high-power electronic equipment, especially in the board-level packaging. However, traditional technology for preparing conductive polymer foam such as electroless plating and electroplating involves serious pollution, a complex fabrication process, and high cost. It is urgent to develop a facile method for the fabrication of highly conductive polymer foam. Herein, we demonstrated a lightweight and flexible silver-wrapped melamine foam (Ag@ME) via in situ sintering of metal-organic decomposition (MOD) at a low temperature (200 °C) on the ME skeleton modified with poly(ethylene imine). The Ag@ME with a continuous 3D conductive network exhibits good compressibility, an excellent conductivity of 158.4 S/m, and a remarkable EMI shielding effectiveness of 63 dB in the broad frequency of 8.2-40 GHz covering X-, Ku-, K-, and Ka-bands, while the volume content is only 2.03 vol %. The attenuation mechanism of Ag@ME for EM waves is systematically investigated by both EM simulation and experimental analysis. Moreover, the practical EMI shielding application of Ag@ME in board-level packaging is demonstrated and it shows outstanding near-field shielding performance. This novel strategy for fabrication of highly conductive polymer foam with low cost and non-pollution could potentially promote the practical applications of Ag@ME in the field of EMI shielding.

7.
ACS Nano ; 14(10): 14134-14145, 2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33044056

RESUMO

Flexible and lightweight high-performance electromagnetic interference shielding materials with minimal thickness, excellent mechanical properties, and outstanding reliability are highly desired in the field of fifth-generation (5G) communication, yet remain extremely challenging to manufacture. Herein, we prepared an ultrathin densified carbon nanotube (CNT) film with superior mechanical properties and ultrahigh shielding effectiveness. Upon complete removal of impurities in pristine CNT film, charge separation in individual CNTs induced by polar molecules leads to strong CNT-CNT attraction and film densification, which significantly improve the electrical conductivity, shielding performance, and mechanical strength. The tensile strength is up to 822 ± 21 MPa, meanwhile the electrical conductivity is as high as 902,712 S/m, and the density is only 1.39 g cm-3. Notably, the shielding effectiveness is over 51 dB with a thickness of merely 1.85 µm in the broad frequency range of 4-18 GHz, and it reaches to ∼82 dB at 6.36 µm and ∼101 dB at 14.7 µm, respectively. Further, such CNT film exhibits excellent reliability after an extended period in strong acid/alkali, high temperature, and high humidity. It demonstrates the best overall performance among representative shielding materials by far, representing a critical breakthrough in the preparation of shielding film toward applications in wearable electronics and 5G communication.

8.
FEBS Lett ; 594(19): 3108-3121, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32671843

RESUMO

Apolipoprotein L1 (APOL1) participates in lipid metabolism. Here, we investigate the mechanisms regulating APOL1 gene expression in hepatoma cells. We demonstrate that the -80-nt to +31-nt region of the APOL1 promoter, which contains one SP transcription factor binding GT box and an interferon regulatory factor (IRF) binding ISRE element, maintains the maximum activity. Mutation of the GT box and ISRE element dramatically reduces APOL1 promoter activity. EMSA and chromatin immunoprecipitation assay reveal that the transcription factors Sp1, IRF1 and IRF2 could interact with their cognate binding sites on the APOL1 promoter. Overexpression of Sp1, IRF1 and IRF2 increases promoter activity, leading to increased APOL1 mRNA and protein levels, while knockdown of Sp1, IRF1 and IRF2 has the opposite effects. These results demonstrate that the APOL1 gene could be regulated by Sp1, IRF1 and IRF2 in hepatoma cells.


Assuntos
Apolipoproteína L1/genética , Carcinoma Hepatocelular/genética , Regulação Neoplásica da Expressão Gênica , Fator Regulador 1 de Interferon/metabolismo , Fator Regulador 2 de Interferon/metabolismo , Neoplasias Hepáticas/genética , Fator de Transcrição Sp1/metabolismo , Transcrição Gênica , Apolipoproteína L1/metabolismo , Sequência de Bases , Linhagem Celular Tumoral , Células HEK293 , Humanos , Regiões Promotoras Genéticas , Ligação Proteica , Elementos de Resposta/genética
9.
Pharmacol Rep ; 72(6): 1706-1716, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32451735

RESUMO

BACKGROUND: In this study, we investigated the effect of forskolin (FSK, a selective adenylate cyclase agonist) on the automatic diastolic depolarization of sinus node cells (SNC) with hypoxia/reoxygenation (H/R) injury. METHODS: The SNC of the newborn rat was randomly assigned into the control group, the H/R (H/R injury) group, or the H/R + FSK (H/R injury + FSK treatment) group. Patch-clamp was performed to record the action potential and electrophysiological changes. The cellular distribution of intracellular calcium concentration was analyzed by fluorescence staining. RESULTS: Compared with the control cells, spontaneous pulsation frequency (SPF) and diastolic depolarization rate (DDR) of H/R cells were reduced from 244.3 ± 10.6 times/min and 108.7 ± 7.8 mV/s to 130.5 ± 7.6 times/min and 53.4 ± 6.5 mV/s, respectively. FSK significantly increased SPF and DDR of H/R cells to 208.3 ± 8.3 times/min and 93.2 ± 8.9 mV/s (n = 15, both p < 0.01), respectively. H/R reduced the current densities of If, ICa,T and inward INCX, which were significantly increased by 10 µM FSK treatment (n = 15, p < 0.01). Furthermore, reduced expression of HCN4 and NCX1.1 channel protein were significantly increased by FSK. Inhibitor studies showed that both SQ22536 (a selective adenylate cyclase inhibitor) and H89 (a selective protein kinases A [PKA] inhibitor) blocked the effects of FSK on SPF and DDR. CONCLUSIONS: H/R causes pacemaker dysfunction in newborn rat sinoatrial node cells leading to divergence of the DD and the slow of spontaneous APs, which change can be dramatically reversed by FSK through increasing INCX and If current in H/R injury.


Assuntos
Potenciais de Ação/efeitos dos fármacos , Cálcio/metabolismo , Colforsina/farmacologia , Nó Sinoatrial/efeitos dos fármacos , Adenilil Ciclases/efeitos dos fármacos , Adenilil Ciclases/metabolismo , Animais , Animais Recém-Nascidos , Hipóxia Celular/efeitos dos fármacos , Células Cultivadas , Feminino , Masculino , Ratos , Ratos Wistar , Nó Sinoatrial/metabolismo
10.
Biochem Biophys Res Commun ; 525(2): 512-519, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32113679

RESUMO

Endothelial inflammation is an important contributor to the pathology of atherosclerotic cardiovascular disease (ASCVD). Circular RNAs (circRNAs) function and role in endothelium inflammation still unknown. In our present study, we firstly identified that circ-RELL1 plays a proinflammatory role in ox-LDL-induced HUVECs through high-throughput circRNA microarray assays. Knockdown circ-RELL1 can reduce the expression of ICAM1 and VCAM1 in ox-LDL induced endothelium inflammation. Mechanistically, circ-RELL1 directly bound to miR-6873-3p in cytoplasm. Subsequently miR-6873-3p reduced MyD88 (myeloid differentiation primary response 88) protein expression and alleviated MyD88 medicated NF-κB activation. Furthermore, circ-RELL1 can abolish the inhibition of inflammation response by miR-6873-3p. Our findings illustrate a novel regulatory pathway that circ-RELL1 modulate inflammatory response by miR-6873-3p/MyD88/NF-κB axis in ox-LDL induced endothelial cells, which provides a potential therapeutic candidate for endothelium inflammation in atherosclerotic cardiovascular disease.


Assuntos
Células Endoteliais/metabolismo , Inflamação/genética , Fator 88 de Diferenciação Mieloide/genética , NF-kappa B/genética , RNA Circular/genética , Células Endoteliais/imunologia , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Células HEK293 , Células Endoteliais da Veia Umbilical Humana , Humanos , Inflamação/imunologia , Lipoproteínas LDL/imunologia , Fator 88 de Diferenciação Mieloide/imunologia , NF-kappa B/imunologia , RNA Circular/imunologia , Regulação para Cima
11.
BMC Nephrol ; 21(1): 90, 2020 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-32156263

RESUMO

BACKGROUND: DD was found to be associated with acute myocardial infarction (AMI) and renal insufficiency. However, it is uncertain whether DD is an independent risk factor of CI-AKI in patients undergoing pPCI. METHODS: We prospectively enrolled 550 consecutive patients with STEMI undergoing pPCI between January 2012 and December 2016. The predictive value of admission DD for CI-AKI was assessed by receiver operating characteristic (ROC) and multivariable logistic regression analysis. CI-AKI was defined as an absolute serum creatinine increase ≥0.3 mg/dl or a relative increase in serum creatinine ≥50% within 48 h of contrast medium exposure. RESULTS: Overall, the incidence of CI-AKI was 13.1%. The ROC analysis showed that the cutoff point of DD was 0.69 µg/ml for predicting CI-AKI with a sensitivity of 77.8% and a specificity of 57.3%. The predictive value of DD was similar to the Mehran score for CI-AKI (AUCDD = 0.729 vs AUCMehran = 0.722; p = 0.8298). Multivariate logistic regression analysis indicated that DD > 0.69 µg/ml was an independent predictor of CI-AKI (odds ratio [OR] = 3.37,95% CI:1.80-6.33, p < 0.0001). Furthermore, DD > 0.69 µg/ml was associated with an increased risk of long-term mortality during a mean follow-up period of 16 months (hazard ratio = 3.41, 95%CI:1.4-8.03, p = 0.005). CONCLUSION: Admission DD > 0.69 µg/ml was a significant and independent predictor of CI-AKI and long-term mortality in patients undergoing pPCI.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/diagnóstico , Meios de Contraste/efeitos adversos , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Intervenção Coronária Percutânea/métodos , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Idoso , Creatinina/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROC , Fatores de Risco , Resultado do Tratamento
12.
Neuroscience ; 433: 230-240, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31982470

RESUMO

OBJECTIVE: The spontaneous action potential of isolated sinoatrial node (SAN) cells is regulated by a coupled-clock system of two clocks: the calcium clock and membrane clock. However, it remains unclear whether calcium clock inhibitors have a direct effect on the membrane clock. The purpose of this study was to investigate the direct effect of cyclopiazonic acid (CPA), a selective calcium clock inhibitor, on the function of the membrane clock of SAN cells. METHODS: at SAN cells were isolated by trypsinization and identified based on morphology and electrophysiology. If and HCN currents were recorded via patch clamp technique. The expression of the HCN channel protein was determined by Western blotting analysis. RESULTS: The diastolic depolarization rate of spontaneous action potentials and the current densities of If were reduced by exposure to 10 µM CPA. The inhibitory effect of CPA was concentration-dependent with an IC50 value of 16.3 µM and a Hill coefficient of 0.98. The effect of CPA on If current was also time-dependent, and the If current amplitude was partially restored after washout. Furthermore, the steady-state activation curve of the If current was shifted to a negative potential, indicating that channel activation slowed down. Finally, the protein expression of HCN4 in HEK293 cells was markedly downregulated by CPA. CONCLUSIONS: These results indicate that the direct inhibition effect of CPA on the If current in SAN cells is both concentration- and time-dependent. The underlying mechanisms may involve slowing down steady-state activation and the downregulation of pacemaker channel protein expression.


Assuntos
Nó Sinoatrial , Potenciais de Ação , Cálcio , Células HEK293 , Humanos , Indóis/farmacologia
13.
World J Clin Cases ; 8(24): 6487-6498, 2020 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-33392335

RESUMO

BACKGROUND: Acquired prosopagnosia is a rare condition characterized by the loss of familiarity with previously known faces and the inability to recognize new ones. It usually occurs after the onset of brain lesions such as in a stroke. The initial identification of prosopagnosia generally relies on a patient's self-report, which can be challenging if it lacks an associated chief complaint. There were few cases of prosopagnosia presenting purely as eye symptoms in the previous literature confirmed by functional magnetic resonance imaging (MRI). CASE SUMMARY: We present a case of delayed diagnosis of prosopagnosia after a right hemisphere stroke in an elderly man whose chief complaint was persistent and progressive "blurred vision" without facial recognition impairment. Ophthalmic tests revealed a homonymous left upper quadrantanopia, with normal visual acuity. He was found by accident to barely recognize familiar faces. The patient showed severe deficit in face recognition and perception tests, and mild memory loss in neuropsychological assessments. Further functional MRI revealed the visual recognition deficits were face-specific. After behavioral intervention, the patient started to rely on other cues to compensate for poor facial recognition. His prosopagnosia showed no obvious improvement eight months after the stroke, which had negative impact on his social network. CONCLUSION: Our case demonstrates that the presentation of prosopagnosia can be atypical, and visual difficulties might be a clinical manifestation solely of prosopagnosia, which emphasizes the importance of routinely considering face recognition impairment among elderly patients with brain lesions.

14.
BMC Nephrol ; 20(1): 201, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31159763

RESUMO

BACKGROUND: A low FT3 level is significantly associated with a variety of kidney disease and acute myocardial infarction (AMI). However, it remains unclear whether low FT3 is associated with CI-AKI in patients who underwent pPCI. METHODS: Single-center retrospective study evaluated 363 STEMI patients undergoing pPCI. Patients were classfied into 2 groups, low FT3 group (FT3 < 3.1 pmol/L) and normal FT3 group (FT3 ≥ 3.1 pmol/L);CI-AKI was defined as an increase in the serum creatinine levels of ≥50% or 0.3 mg/dL above the baseline level within 48 h after contrast medium exposure. RESULTS: Overall, 80(22.0%) patients had low FT3, and 59(16.3%) patients developed CI-AKI. The incidence of CI-AKI and in-hospital mortality was significantly higher in patients with low FT3 than normal (31.3% vs 12.0%; 15.0% vs 3.2%, respectively, both p < 0.0001). Multivariate logistic regression analysis indicated that low FT3 was an independent predictor of CI-AKI (odds ratio [OR] = 2.62, 95%CI:1.35-5.07, p < 0.05). In addition, low FT3 was associated with an increased risk of all-cause mortality during a mean follow-up period of 20 months (hazard ratio [HR] = 2.54, 95%CI:1.15-5.60, p < 0.05). CONCLUSION: Low FT3 was associated with CI-AKI, short- and long-term mortality in STEMI patients after pPCI.


Assuntos
Injúria Renal Aguda , Intervenção Coronária Percutânea , Tri-Iodotironina/análise , Injúria Renal Aguda/sangue , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/epidemiologia , Meios de Contraste/efeitos adversos , Feminino , Mortalidade Hospitalar , Humanos , Incidência , Testes de Função Renal/métodos , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Estudos Retrospectivos , Fatores de Risco
15.
J Cell Mol Med ; 23(4): 3032-3039, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30697920

RESUMO

OBJECTIVE: This study aimed to investigate the effects of transforming growth factor ß1 (TGF ß1) and hepatocyte growth factor (HGF) on the expression of connective tissue growth factor (CTGF) in human atrial fibroblasts, and to explore the relationship of these factors in atrial fibrosis and atrial anatomical remodelling (AAR) of patients with atrial fibrillation (AF). METHODS: Fresh right auricular appendix tissue of 20 patients with rheumatic heart disease undergoing valve replacement surgery was collected during surgeries, 10 patients had sinus rhythm(SR), and 10 patients had chronic atrial fibrillation (CAF). Atrial fibroblasts were then cultured from the tissues with differential attachment technique and treated with either TGFß1 (10 ng/mL) or HGF (100 ng/mL). CTGF mRNA levels were measured by RT-PCR, and CTGF protein content was determined using immunofluorescence and Western blotting assays. RESULTS: CAF group had higher left atrial diameters (LADs) and higher CTGF mRNA expression in atrial fibroblasts compared with SR group. The CTGF protein content in CAF group was higher than that of SR group and positively correlated with LAD and AF duration. After CAF group was treated with TGFß1, CTGF mRNA and protein expression were significantly down-regulated, whereas when treated with HGF, expression was up-regulated compared with SR group. CONCLUSIONS: Increased CTGF expression was associated with enlarged LAD, atrial fibrosis and AAR in patients with AF. TGFß1 and HGF regulate CTGF expression in human atrial fibroblasts with up-regulation of mRNA and down-regulation of protein, therefore, either promote or inhibit atrial fibrosis, which could be related to the incidence and persistence of AF.


Assuntos
Remodelamento Atrial , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Fibroblastos/patologia , Fibrose/etiologia , Fator de Crescimento de Hepatócito/metabolismo , Cardiopatia Reumática/complicações , Fator de Crescimento Transformador beta1/metabolismo , Adulto , Fibrilação Atrial/etiologia , Fibrilação Atrial/metabolismo , Fibrilação Atrial/patologia , Células Cultivadas , Fator de Crescimento do Tecido Conjuntivo/genética , Feminino , Fibroblastos/metabolismo , Fibrose/metabolismo , Fibrose/patologia , Fator de Crescimento de Hepatócito/genética , Humanos , Masculino , Cardiopatia Reumática/metabolismo , Cardiopatia Reumática/patologia , Fator de Crescimento Transformador beta1/genética
16.
Front Physiol ; 9: 1447, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30450052

RESUMO

Aim: We investigated the underlying mechanisms in atrial fibrillation (AF) associated with R33Q mutation and Ca2+-triggered activity. Methods and Results: We examined AF susceptibility with intraesophageal burst pacing in the sarcoplasmic reticulum (SR) Ca2+ leak model calsequestrin 2 R33Q (Casq2R33Q/R33Q) mice. Atrial trigger appeared in R33Q mice but not WT mice (17.24%, 5/29 vs. 0.00%, 0/32, P < 0.05). AF was induced by 25 Hz pacing in R33Q mice (48.27%, 14/29 vs. 6.25%, 2/32, P < 0.01). The mice were given 1.5 mg/kg isoproterenol (Iso), and the incidences of AF increased (65.51%, 19/29 vs. 9.21%, 3/32, P < 0.01). Electrophysiology experiments and the recording of intracellular Ca2+ indicated significant increases in the Ca2+ sparks (5.24 ± 0.75 100 µM-1.s-1 vs. 0.29 ± 0.04 100 µM-1.s-1, n = 20, P < 0.05), intracellular free Ca2+ (0.238 ± 0.009 µM vs. 0.172 ± 0.006 µM, n = 20, P < 0.05), Ca2+ wave (11.74% vs. 2.24%, n = 20, P < 0.05), transient inward current (ITi) (-0.56 ± 0.02 pA/pF vs. -0.42 ± 0.01 pA/pF, n = 10, P < 0.05), and oscillation in membrane potentials (10.71%, 3/28 vs. 4.16%, 1/24, P < 0.05) in the R33Q group, but there was no significant difference in the L-type calcium current. These effects were enhanced by Iso, and the inhibition of calmodulin-dependent protein kinase II (CaMKII) by 1 µM KN93 reversed the effects of Iso on Ca2+ sparks (5.01 ± 0.66 100 µm-1.s-1 vs. 11.33 ± 1.63 100 µm-1.s-1, P < 0.05), intracellular Ca2+ (0.245 ± 0.005 µM vs. 0.324 ± 0.008 µM, P < 0.05), Ca2+ wave (12.35% vs. 17.83%, P < 0.05), ITi (-0.61 ± 0.02 pA/pF vs. -0.78 ± 0.03 pA/pF, n = 10, P < 0.05), and oscillation in membrane potential (17.85% 5/28 vs. 32.17% 9/28, P < 0.05). The reduction of ryanodine receptor 2 (RyR2) stable subunits (Casq2, triadin, and junctin) rather than RYR2 and the increase in CaMKII, phosphor-CaMKII, phosphor-RyR2 (Ser 2814), SERCA, and NCX1.1 was reflected in the R33Q group. Conclusion: This study demonstrates that the increase in spontaneous calcium elevations corresponding to ITi that may trigger the oscillation in membrane potentials in the R33Q group, thereby increasing the risk of AF. The occurrence of spontaneous calcium elevations in R33Q atrial myocytes is due to the dysfunction of RyR2 stable subunits, CaMKII hyperactivity, and CaMKII-mediated RyR phosphorylation. An effective therapeutic strategy to intervene in Ca2+-induced AF associated with the R33Q mutation may be through CaMKII inhibition.

17.
Int Heart J ; 59(5): 926-934, 2018 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-30158378

RESUMO

The aim of the study is to evaluate the association of pre-procedural N-terminal pro-B type natriuretic peptide (NT-proBNP) with contrast-induced acute kidney injury (CI-AKI) and long-term outcomes in elderly patients undergoing elective percutaneous coronary intervention (PCI).A total of 540 patients aged ≥ 75 years who had undergone elective PCI between January 2012 and December 2015 were enrolled in this study. Admission NT-proBNP levels were measured before PCI. CI-AKI was defined as a relative increase in serum creatinine (SCr) of ≥50%, or an absolute increase of ≥ 0.3 mg/dL, occurring within 48 hours after contrast medium exposure. The predictive value of NT-proBNP for predicting CI-AKI was assessed by receiver operating characteristic (ROC) and multivariable logistic regression analysis.A total of 54 (10.0%) patients developed CI-AKI. The best cutoff value of NT-pro-BNP for detecting CI-AKI was 1133 pg/mL with 66.7% sensitivity and 70.8% specificity according to the ROC analysis (C statistic = 0.719; 95% CI, 0.679-0.756). Multivariable analysis demonstrated that Lg-NT-proBNP is significantly related to CI-AKI (odds ratio [OR] = 3.892; 95% CI, 1.996-7.590; P < 0.001). Cox regression analysis showed that Lg-NT-proBNP is associated with long-term mortality (adjusted hazard ratio [HR] = 2.158; 95% CI, 1.246-3.740; P = 0.006) during follow-up.Pre-procedural NT-proBNP is a significant and independent predictor of CI-AKI and long-term mortality in elderly patients following elective PCI, and the best cutoff point for predicting CI-AKI was 1133 pg/mL.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Doença da Artéria Coronariana/diagnóstico por imagem , Rim/lesões , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Intervenção Coronária Percutânea/efeitos adversos , Cuidados Pré-Operatórios/normas , Injúria Renal Aguda/metabolismo , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Meios de Contraste/efeitos adversos , Doença da Artéria Coronariana/cirurgia , Creatinina/sangue , Procedimentos Cirúrgicos Eletivos/métodos , Feminino , Humanos , Rim/patologia , Tempo de Internação/tendências , Masculino , Avaliação de Resultados em Cuidados de Saúde , Intervenção Coronária Percutânea/mortalidade , Valor Preditivo dos Testes , Estudos Prospectivos
18.
Small ; 14(27): e1800534, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29847702

RESUMO

Metal-based materials with exceptional intrinsic conductivity own excellent electromagnetic interference (EMI) shielding performance. However, high density, corrosion susceptibility, and poor flexibility of the metal severely restrict their further applications in the areas of aircraft/aerospace, portable and wearable smart electronics. Herein, a lightweight, flexible, and anticorrosive silver nanowire wrapped carbon hybrid sponge (Ag@C) is fabricated and employed as ultrahigh efficiency EMI shielding material. The interconnected Ag@C hybrid sponges provide an effective way for electron transport, leading to a remarkable conductivity of 363.1 S m-1 and superb EMI shielding effectiveness of around 70.1 dB in the frequency range of 8.2-18 GHz, while the density is as low as 0.00382 g cm-3 , which are among the best performances for electrically conductive sponges/aerogels/foams by far. More importantly, the Ag@C sponge surprisingly exhibits super-hydrophobicity and strong corrosion resistance. In addition, the hybrid sponges possess excellent mechanical resilience even with a large strain (90% reversible compressibility) and an outstanding cycling stability, which is far better than the bare metallic aerogels, such as silver nanowire aerogels and copper nanowire foams. This strategy provides a facile methodology to fabricate lightweight, flexible, and anticorrosive metal-based sponge for highly efficient EMI shielding applications.

19.
Clin Interv Aging ; 13: 641-649, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29713148

RESUMO

PURPOSE: Inflammatory factors play a critical role in contrast-induced acute kidney injury (CI-AKI). Prealbumin, a nutritional and inflammatory indicator, is a well-established predictor of short- and long-term outcomes in numerous clinical conditions. The current study investigated the association of pre-procedural prealbumin levels with CI-AKI and long-term outcomes in geriatric patients after elective percutaneous coronary intervention (PCI). PATIENTS AND METHODS: A total of 558 patients aged≥75 years, who underwent elective PCI between January 2012 and December 2015, were selected for the current study. Pre-procedural prealbumin levels were measured before PCI. Multivariable logistic regression and Cox proportional hazard regression analyses were performed to identify the independent risk factors for CI-AKI and long-term mortality. RESULTS: Out of 558 patients, 54 developed CI-AKI. The optimal cutoff value of prealbumin for detecting CI-AKI was 185.5 mg/L with 62.7% sensitivity and 70.4% specificity based on the receiver operating characteristic analysis (C-statistic=0.710; 95% confidence interval [CI] 0.673-0.751). Multivariable analysis demonstrated that prealbumin≤185.5 mg/L was significantly associated with CI-AKI (odds ratio [OR] 0.397; 95% CI 0.195-0.808; P=0.011). Cox regression analysis demonstrated that prealbumin≤185.5 mg/L was associated with long-term mortality (adjusted hazard ratio [HR] 0.525; 95% CI 0.289-0.952; P=0.034) during the follow-up. CONCLUSION: Pre-procedural levels of prealbumin were independently associated with an increased risk of CI-AKI and long-term mortality in elderly patients undergoing elective PCI.


Assuntos
Injúria Renal Aguda , Meios de Contraste/efeitos adversos , Peptídeo Natriurético Encefálico/análise , Fragmentos de Peptídeos/análise , Intervenção Coronária Percutânea , Complicações Pós-Operatórias , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/prevenção & controle , Idoso , Procedimentos Cirúrgicos Eletivos , Feminino , Humanos , Efeitos Adversos de Longa Duração/induzido quimicamente , Efeitos Adversos de Longa Duração/epidemiologia , Efeitos Adversos de Longa Duração/prevenção & controle , Masculino , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Pré-Albumina/análise , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Fatores de Risco
20.
Angiology ; 69(9): 770-778, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29463106

RESUMO

We investigated whether preprocedural hyperglycemia was associated with contrast-induced acute kidney injury (CI-AKI) and long-term outcomes in patients with acute coronary syndrome (ACS) who underwent emergency percutaneous coronary intervention (PCI). Patients (n = 558) with ACS who underwent emergency PCI were consecutively enrolled. Preprocedural hyperglycemia was defined as glucose levels >198 mg/dL (11 mmol/L). The primary outcome was CI-AKI (≥0.3 mg/dL absolute or ≥50% relative serum creatinine increase 48 hours after contrast medium exposure). Overall, 103 (18.5%) patients had preprocedural hyperglycemia and 89 (15.9%) patients developed CI-AKI. The incidence of CI-AKI was significantly higher in patients with hyperglycemia than without (28.2% vs 13.2%; P < .01). Multivariate analysis indicated that preprocedural hyperglycemia was an independent predictor of CI-AKI (odds ratio = 1.971, 95% confidence interval [CI]: 1.129-3.441; P < .05). In addition, preprocedural hyperglycemia was associated with an increased risk of all-cause mortality during the 2-year follow-up (hazard ratio = 2.440, 95% CI: 1.394-4.273; P = .002). Preprocedural hyperglycemia is a significant and independent predictor of CI-AKI and long-term outcomes.


Assuntos
Síndrome Coronariana Aguda/cirurgia , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/diagnóstico , Meios de Contraste/efeitos adversos , Hiperglicemia/complicações , Intervenção Coronária Percutânea , Síndrome Coronariana Aguda/complicações , Idoso , Serviços Médicos de Emergência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Resultado do Tratamento
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