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2.
Herz ; 45(2): 192-198, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29869699

RESUMO

BACKGROUND: Although balloon sizing has been found to be useful during transcatheter aortic valve implantation (TAVI), its effectiveness in patients with bicuspid aortic valve (BiAV) remains unknown. METHODS: Patients who underwent balloon sizing were retrospectively identified. The study comprised 67 patients (61.2% with BiAV). Preprocedural hypothetical transcatheter heart valve (THV) sizing was based on multislice computed tomography (MSCT) measurements at the annulus. Changes in valve size after balloon sizing were reviewed. Postprocedural MSCT measurements and the grade of paravalvular aortic regurgitation (PAR) were compared. RESULTS: When comparing patients with a BiAV and those with a tricuspid aortic valve (TiAV), there was no significant difference (p = 0.97) in the proportion of decreased (43.9% vs. 46.2%), unchanged (51.2% vs. 50.0%), or increased (4.9% vs. 3.8%) valve sizes chosen on the basis of MSCT findings. The anticipated annular sizing ratio for patients who received a smaller valve was 7.2% (3.5-10.5%) while it was 15.7% (12.5-19.0) for the others (p < 0.01), and no significant difference in the proportion of mild (or more severe) PAR cases was found between the groups (37.9% vs. 30.6%, p = 0.53 at the 1­month follow-up). Stent frame expansion and eccentricity index were comparable between the BiAV and TiAV subgroups among patients who received a smaller THV after balloon sizing. CONCLUSION: Balloon sizing is a useful tool that is complementary to the current gold standard of MSCT for THV size selection as well as for BiAV morphology assessment.


Assuntos
Estenose da Valva Aórtica , Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Intervenção Coronária Percutânea , Substituição da Valva Aórtica Transcateter , Idoso , Valva Aórtica , Humanos , Masculino , Tomografia Computadorizada Multidetectores , Desenho de Prótese , Estudos Retrospectivos , Resultado do Tratamento
3.
Sci Rep ; 9(1): 3642, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30842466

RESUMO

The state-of-art Si Matel-Oxide-Semiconductor Field-Effect-Transistor (MOS-FET) meets the problem of the Power Consumption (PC) can not be effecively deceased guided by the Moore's Law as before. The GFET has the problem of the device can not be effectively turned off, since the band-gap of the graphene is zero. To solve these problems, noticing the amount of the carriers in the 2 dementional semiconductor material is limited, we propose a Matel-Semi-Insulator-Semiconductor Field-Effect-Transistor (MSIS-FET) to replace the traditional MOS-FET. We verify our idea by fabricating the graphene MSIS-FETs using the natural Aluminium-oxide (Al-oxide) as the semi-insulator gate dielectric. From MSIS-FETs fabricated, we obtain following experimental results. The graphene MSIS-FET is turned off very well, a recorded high Ids on/off ratio of 5 × 107 is achieved. A saddle and close-loop shape transfer feature of Ids-Vgs is obtained first time for transistors. A non-volatile memory characteristics is observed. A carrier re-injection principle and a super-Low PC mechanism for semiconductor devices and integrated circuits (ICs) are found from the transfer feature of the graphene MSIS-FET. It is shown that the PC of the semiconductor devices and (ICs) can be reduced by over three orders of magnitude by using this new mechanism.

4.
J Nutr Health Aging ; 20(2): 199-204, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26812517

RESUMO

OBJECTIVE: To explore whether nutritional risk is associated with poor outcomes independent of complicated clinical status in older patients with coronary artery disease (CAD). DESIGN: Cohort study. SETTING: Patients referred for coronary angiography in West China Hospital, Sichuan University, China. PARTICIPANTS: 1772 patients with angiographic documented CAD whose age was above 65 years. MEASUREMENTS: Nutritional state was appraised using geriatric nutritional risk index (GNRI). Nutritional risk was defined as the GNRI below 98. The event rate of all-cause death was observed among patients with nutritional risk and those without. RESULTS: During a median follow-up period of 27 months, 224 patients died. Multivariate Cox regression analysis showed that nutritional risk was associated with all-cause death (adjusted hazard ratio 1.99; 95% confidence interval 1.35-2.95; P=0.001). Subgroup analysis verified the association between nutritional risk and death among patients with distinct clinical features, comorbidities, and medication. There was no interaction between nutritional risk and clinical characteristics with regard to all-cause death. CONCLUSION: Nutritional state is independently associated with the risk of all-cause death in geriatric patients with CAD. Whether nutritional support in appropriate patients improves clinical outcomes deserves further investigation.


Assuntos
Causas de Morte , Comorbidade , Doença da Artéria Coronariana/complicações , Desnutrição/complicações , Estado Nutricional , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Estudos de Coortes , Doença da Artéria Coronariana/mortalidade , Feminino , Humanos , Masculino , Desnutrição/mortalidade , Apoio Nutricional , Modelos de Riscos Proporcionais , Análise de Regressão , Fatores de Risco
5.
QJM ; 108(8): 641-7, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25609701

RESUMO

BACKGROUND: 'Obesity paradox' was not consistently observed in Asians with coronary artery disease (CAD). AIM: The study investigated the association between body composition and outcomes in Chinese patients with CAD. DESIGN: Cohort study. METHOD: A total of 3280 patients with angiographically validated CAD were consecutively included. Body fat (BF) percentage and lean mass index (LMI) were evaluated using the Clínica Universidad de Navarra-Body Adiposity Estimator. The rate of mortality from any cause was compared across groups classified by the quartiles of LMI. RESULTS: During a median period of 24 months, 288 (8.8%) participants died. There was a close association between increasing LMI and reducing mortality rate. However, univariate analyses did not find protective effect of BF on survival. After adjusting for age, sex, diabetes, current smoking, systolic blood pressure, creatinine, white blood cell count, haemoglobin and medication, Cox regression analyses showed that the significant relation between higher quartiles (Q) of LMI and survival benefit (Q4, hazard ratio 0.58 (95% confidence interval: 0.36-0.94) vs. Q3, 0.60 (0.39-0.91) vs. Q2, 0.60 (0.41-0.88) vs. Q1, reference) remained. CONCLUSION: Low LMI but not BF predicts all-cause mortality in Chinese patients with CAD.


Assuntos
Tecido Adiposo/patologia , Composição Corporal/fisiologia , Doença da Artéria Coronariana/fisiopatologia , Adiposidade/fisiologia , Idoso , Antropometria/métodos , Índice de Massa Corporal , China/epidemiologia , Doença da Artéria Coronariana/mortalidade , Doença da Artéria Coronariana/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Análise de Sobrevida
6.
Intern Med J ; 45(3): 275-83, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25510963

RESUMO

BACKGROUND: There is debate regarding the predictive value of interventricular septum (IVS) wall thickness for adverse events. AIMS: The study investigated the association between the severity of thickened IVS and all-cause death in Chinese patients with coronary artery disease (CAD). METHODS: A total of 2297 CAD patients verified by angiography was consecutively included. Patients were grouped according to the severity of thickened IVS. Cox regression analysis was conducted to determine the independent prognostic value of thickened IVS for all-cause death. RESULTS: During a median follow up of 25 months, 149 patients died. A gradient increase in the risk of death was observed across thickened IVS groups. Compared to patients with normal IVS thickness, the adjusted hazard ratio (HR) was 1.49 (95% confidence interval (CI) 1.00-2.23, P = 0.05) and 2.13 (95% CI 1.29-3.54, P = 0.003) for all-cause death in those with mildly and moderately/severely thickened IVS respectively. For one unit increase in IVS thickness, the risk of all-cause death was elevated by 14% (adjusted HR 1.14, 95% CI 1.05-1.24, P = 0.003). In patients with normal indexed left ventricular mass, thickened IVS was also demonstrated as an independent risk factor for all-cause death. CONCLUSION: Thickened IVS can be served as a reliable marker for predicting all-cause death in Chinese patients with CAD, even in those with normal left ventricular mass.


Assuntos
Causas de Morte , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/mortalidade , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/mortalidade , Septo Interventricular/diagnóstico por imagem , Idoso , Causas de Morte/tendências , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Radiografia
7.
Br J Cancer ; 110(7): 1767-77, 2014 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-24504366

RESUMO

BACKGROUND: EIF5A2, eukaryotic translation initiation factor 5A2, is associated with several human cancers. In this study, we investigated the role of EIF5A2 in the metastatic potential of localised invasive bladder cancer (BC) and its underlying molecular mechanisms were explored. METHODS: The expression pattern of EIF5A2 in localised invasive BC was determined by immunohistochemistry. In addition, the function of EIF5A2 in BC and its underlying mechanisms were elucidated with a series of in vitro and in vivo assays. RESULTS: Overexpression of EIF5A2 was an independent predictor for poor metastasis-free survival of localised invasive BC patients treated with radical cystectomy. Knockdown of EIF5A2 inhibited BC cell migratory and invasive capacities in vitro and metastatic potential in vivo and reversed epithelial-mesenchymal transition (EMT), whereas overexpression of EIF5A2 promoted BC cells motility and invasiveness in vitro and metastatic potential in vivo and induced EMT. In addition, we found that EIF5A2 might activate TGF-ß1 expression to induce EMT and drive aggressiveness in BC cells. EIF5A2 stabilized STAT3 and stimulated nuclear localisation of STAT3, which resulted in increasing enrichment of STAT3 onto TGF-ß1 promoter to enhance the transcription of TGF-ß1. CONCLUSIONS: EIF5A2 overexpression predicts tumour metastatic potential in patients with localised invasive BC treated with radical cystectomy. Furthermore, EIF5A2 elevated TGF-ß1 expression through STAT3 to induce EMT and promotes aggressiveness in BC.


Assuntos
Biomarcadores Tumorais/metabolismo , Movimento Celular/genética , Fatores de Iniciação de Peptídeos/metabolismo , Proteínas de Ligação a RNA/metabolismo , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/patologia , Animais , Células Cultivadas , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Prognóstico , Estudos Retrospectivos , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo , Neoplasias da Bexiga Urinária/genética , Fator de Iniciação de Tradução Eucariótico 5A
8.
Appl Opt ; 48(13): 2480-4, 2009 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19412206

RESUMO

High-quality three-dimensional photonic crystal (PC) heterostructures were fabricated using the modified self-assembly method, and their structural and optical properties were analyzed. Results suggest that the optical quality of heterostructures formed by depositing bigger particles on small ones is superior to that of heterostructures formed by stacking smaller particles on big ones, due to the rough interface effects in the latter structure. The roughness of the interface in the latter structure can be largely improved by introducing a thin two-dimensional planar defect layer into the PCs, and significant progress in the quality of the heterostructures is achieved. The important role of the thin planar defect layer in the quality of the heterostructures was also verified by numerical simulations.

9.
Opt Express ; 17(21): 18501-12, 2009 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-20372580

RESUMO

Three multiplexing schemes are presented for polarization-maintaining photonic crystal fiber based Sagnac interferometric sensors. The first technique is wavelength division multiplexing using coarse wavelength division multiplexers (CWDMs) to distinguish signals from each multiplexed sensor in different wavelength channels. The other two schemes are to multiplex sensors in series along a single fiber link and in parallel by using fiber-optic couplers. While for the CWDM scheme, the multiplexed sensing signal can be obtained by direct measurement; for the other two multiplexing techniques, the sensing signal is more complex and cannot be easily demultiplexed. Thus, some signal processing methods are required. In this regard, two mathematical transformations, namely the discrete wavelet transform and Fourier transform, have been independently and successfully implemented into these two schemes. The operating principles, experimental setup, and overall performance are discussed.

10.
Opt Lett ; 33(8): 845-7, 2008 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18414552

RESUMO

Broadband, compact in-fiber polarizers were fabricated using a pulsed CO(2) laser to modify the air holes along one side of the hollow-core photonic bandgap fibers. The polarizers have lengths from 3 to 6 mm and exhibit a polarization extinction ratio of better than 20 dB over a wavelength range larger than 100 nm at approximately 1,550 nm.

11.
Appl Opt ; 40(7): 1011-20, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-18357084

RESUMO

We report on the use of a frequency-modulated continuous-wave technique for multiplexing optical fiber gas sensors. The sensor network is of a ladder topology and is interrogated by a tunable laser. The system performance in terms of detection sensitivity and cross talk between sensors was investigated and found to be limited by coherent mixing between signals from different channels. The system performance can be improved significantly by use of appropriate wavelength modulation-scanning coupled with low-pass filtering. Computer simulation shows that an array of 37 acetylene sensors with a detection accuracy of 2000 parts in 10(6) for each sensor may be realized. A two-sensor acetylene detection system was experimentally demonstrated that had a detection sensitivity of 165 parts in 10(6) for 2.5-cm gas cells (or a minimum detectable absorbance of 2.1 x 10(-4)) and a cross talk of -25 dB.

12.
Sheng Li Xue Bao ; 44(2): 181-5, 1992 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-1535724

RESUMO

By means of technique of cell culture, 3H-thymidine incorporation and dot blot, it was demonstrated that angiotensin II (AGT II) stimulated proliferation and c-fos oncogene expression in cultured SHR vascular smooth muscle cells (VSMC) in a dose-dependent manner. This effect of AGT II was significantly inhibited by co-incubation with ANP. The results suggest that proliferation of VSMC is regulated by some interaction between AGT II and ANP.


Assuntos
Angiotensina II/farmacologia , Fator Natriurético Atrial/farmacologia , Genes fos , Músculo Liso Vascular/efeitos dos fármacos , Animais , Aorta , Divisão Celular , Células Cultivadas , Feminino , Regulação da Expressão Gênica , Masculino , Músculo Liso Vascular/citologia , Ratos , Ratos Endogâmicos SHR
13.
Sheng Li Xue Bao ; 43(4): 368-75, 1991 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-1661442

RESUMO

The specific binding sites for atrial natriuretic peptide (ANP) were present in cultured vascular smooth muscle cells (VSMC) from stroke-prone spontaneously hypertensive (SHRsp) and Wistar-Kyoto(WKY) rats with a Bmax of 3.65 +/- 0.13 and 1.89 +/- 0.09 pmol/mg pr. and a Kd of 72.0 +/- 10.2 and 42.1 +/- 4.8 x 10(-12) mol/L, respectively. The basal levels of cGMP of the two strains showed no statistical difference. After treatment with ANP (1.67 x 10(-7) mol/L) for 5 min, the cGMP levels of VSMC were increased by 139 folds in SHRsp and 271 folds in WKY rats, i.e., cGMP levels were significantly lower in the former (P less than 0.01). Therefore, the cultured VSMC of SHRsp had higher ANP receptor density but lower affinity and responsiveness to ANP than that of WKY rats. After incubation of VSMC in the medium containing high NaCl (2-folds of normal) at 37 degrees C for 24 h, the number of ANP binding sites decreased to 34.8 +/- 8.2% in SHRsp and to 38.6 +/- 9.4% in WKY rats (P less than 0.01) with a parallel decrease of cGMP, while the affinity of ANP receptor did not change. It is suggested that the lower responsiveness of ANP receptor to ANP in SHRsp might result in a diminution of vasorelaxation to ANP and thus an increase of arterial pressure. In addition, the more down-regulation of ANP receptor by high NaCl in cultured VSMC from SHRsp implicates that it is one of the mechanisms that high dietary intake of NaCl might enhance high blood pressure.


Assuntos
Fator Natriurético Atrial/fisiologia , Músculo Liso Vascular/metabolismo , Receptores de Superfície Celular/fisiologia , Animais , Aorta , Células Cultivadas , GMP Cíclico/metabolismo , Regulação para Baixo/efeitos dos fármacos , Masculino , Músculo Liso Vascular/citologia , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Cloreto de Sódio/farmacologia
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