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1.
Phys Chem Chem Phys ; 25(47): 32452-32459, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37991918

RESUMO

A15-type compound Nb3Sn has attracted much attention due to its relatively high critical temperature and critical field of superconductivity, making it a leading material for superconducting applications. In this study, we investigate the structural instability and superconductivity of Nb3Sn under hydrostatic pressure using first-principles calculations. We determine the electronic properties, phonon dispersion, electron-phonon coupling and the superconducting gap for Nb3Sn at pressures ranging from ambient to 9 GPa. Our results show that a significant electron density is present near the Fermi level due to the van Hove singularity, indicating the strong electron-phonon coupling. The phonon dispersion of Nb3Sn exhibits Kohn anomalies at three different wave vectors at a lower temperature. Moreover, above a pressure of 6 GPa, the charge density wave (CDW) instability disappeared, suggesting that pressure inhibits the CDW phase. The superconducting temperature is predicted to be TC = 18.62 K under ambient conditions, which is well consistent with the experimental results. We find that both the CDW and superconducting orders respond to pressure, with their transition temperatures decreasing as the pressure increases below 6 GPa. Above 6 GPa, the superconducting transition temperature increases slowly with pressure. Our results suggest that the instability in Nb3Sn is driven by the softening of the phonon modes due to the CDW caused by strong electron-phonon coupling. Therefore, the CDW phase and superconducting phase of Nb3Sn coexist at low pressure.

2.
Cardiovasc Diabetol ; 17(1): 149, 2018 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-30482197

RESUMO

BACKGROUND: Negative coronary artery remodeling is frequent in patients with diabetes, but its mechanism remains unclear. We here evaluated the association of serum levels of glycated albumin (GA) and endogenous secretory receptor for advanced glycation end products (esRAGE) with coronary artery remodeling in type 2 diabetic patients. METHODS: Serum levels of GA and esRAGE were measured and intravascular ultrasound was performed in 136 consecutive diabetic patients with 143 coronary intermediate lesions. The remodeling index (RI) was calculated as the ratio between external elastic membrane (EEM) area at the lesion site and EEM area at the reference segment. Negative remodeling (NR) was defined as an RI < 0.95 and intermediate or positive remodeling as an RI ≥ 0.95. RESULTS: Mean plaque burden at the lesion site was 70.96 ± 9.98%, and RI was 0.96 ± 0.18. Negative coronary arterial remodeling existed in 81 (56.6%) lesions. RI correlated closely with serum esRAGE level (r = 0.236, P = 0.005) and was inversely related to serum GA level (r = - 0.240, P = 0.004) and plasma low-density lipoprotein cholesterol (LDL-C) (r = - 0.206, P = 0.014) and total cholesterol levels (r = - 0.183, P = 0.028). Generalized estimating equations logistic regression analysis identified esRAGE (OR 0.037; 95% CI 0.012-0.564, P = 0.021), GA (OR 1.093; 95% CI 1.013-1.179, P = 0.018) and LDL-C (OR 1.479; 95% CI 1.072-2.835, P = 0.023) as independent predictors for negative remodeling. CONCLUSIONS: In diabetic patients, negative coronary artery remodeling is associated with increased GA and decreased esRAGE levels in serum.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Diabetes Mellitus Tipo 2/sangue , Hemoglobinas Glicadas/metabolismo , Receptor para Produtos Finais de Glicação Avançada/sangue , Ultrassonografia de Intervenção , Remodelação Vascular , Idoso , Biomarcadores/sangue , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/etiologia , Doença da Artéria Coronariana/patologia , Vasos Coronários/patologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Feminino , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica , Valor Preditivo dos Testes
3.
Catheter Cardiovasc Interv ; 87 Suppl 1: 616-23, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26864270

RESUMO

BACKGROUND: There is increasing interest in percutaneous coronary intervention (PCI) for chronic total occlusions (CTO). Periprocedural myocardial injury (PMI) post CTO PCI is not uncommon, but true incidence and implications of PMI are not well understood. OBJECTIVES: This study aimed to investigate risk factors for PMI post CTO PCI and its implications for the 1-year clinical outcome of a Chinese population. METHODS: Baseline characteristics, procedure features, and major adverse cardiac events (MACE) at 1 year were assessed in 629 consecutive patients who underwent CTO PCI. PMI was diagnosed as an elevation of creatine kinase MB ≥3 times ULN 12-24 hr post procedure. Multivariate analysis was performed to determine the correlates of PMI and MACE at 1-year follow-up. RESULTS: In total, PMI was detected in 115 patients (18.3%). Compared with patients without PMI, those with PMI had a higher percentage of previous coronary artery bypass grafting (CABG), right coronary occlusion and side branch occlusion, and technical success was lower in the PMI group (90.4% vs. 96.7%, P = 0.003). One-year MACE-free survival was reduced in the PMI group (87.8% vs. 95.9%, P = 0.001). The final TIMI flow 0-1 (OR 2.23, 95%CI 1.06-4.87, P = 0.02), side branch occlusion (OR 2.67, 95%CI 1.19-7.11, P = 0.009), retrograde PCI (OR 1.35, 95%CI 1.10-2.74, P = 0.04), and history of prior CABG (OR 2.41, 95%CI 1.38-5.91, P = 0.01) were independent risk factors for the occurrence of PMI. CONCLUSIONS: In this unique Chinese cohort, PMI post CTO PCI was associated with several clinical and angiographic factors and exerts an adverse effect on 1-year clinical outcomes.


Assuntos
Oclusão Coronária/terapia , Cardiopatias/etiologia , Intervenção Coronária Percutânea/efeitos adversos , Idoso , Biomarcadores/sangue , Distribuição de Qui-Quadrado , China , Doença Crônica , Angiografia Coronária , Oclusão Coronária/diagnóstico por imagem , Oclusão Coronária/mortalidade , Creatina Quinase Forma MB/sangue , Intervalo Livre de Doença , Stents Farmacológicos , Feminino , Cardiopatias/sangue , Cardiopatias/diagnóstico , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Intervenção Coronária Percutânea/instrumentação , Intervenção Coronária Percutânea/mortalidade , Sistema de Registros , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
4.
Catheter Cardiovasc Interv ; 85 Suppl 1: 762-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25630513

RESUMO

BACKGROUND AND PURPOSE: Patients are at risk of developing periprocedural myonecrosis after percutaneous coronary intervention (PCI). We investigated whether the use of the platelet glycoprotein (GP) IIb/IIIa receptor inhibitor tirofiban could reduce periprocedural myocardial infarction (PMI) in patients with stable coronary artery disease undergoing elective PCI with overlapping stent implantation for long lesions. METHODS: A total of 748 stable angina patients with long lesions (≥ 40 mm in length) treated with overlapping stent implantation were randomly assigned to receive tirofiban (tirofiban group; n = 373) or conventional therapy (control group; n = 375). Intravenous tirofiban was initiated before PCI and maintained for 12 hr after the procedure. The primary endpoint was PMI, defined as an elevation in CK-MB > 3 times the upper limit of normal 12 hr after the index procedure. The secondary endpoint was major adverse cardiac events (MACE), including cardiac death, target vessel revascularization, and recurrent MI (re-MI), at one-year of clinical follow-up. The safety end-points included Thrombolysis in Myocardial Infarction (TIMI) major bleeding and stent thrombosis. RESULTS: Despite comparable angiographic and procedural characteristics, in the intention-to-treatment analysis, the primary endpoint was significantly reduced in the tirofiban group (4.0% vs. 11.5%, P < 0.001). Multivariate analysis revealed that the adjunctive use of tirofiban was the only negative predictor of PMI (OR 0.41, 95% CI 0.28-0.81, P < 0.01). At one-year of clinical follow-up, the overall occurrence of MACE was significantly lower in the tirofiban group (13.4% vs. 22.7%, P = 0.001). The rate of TIMI major bleeding and stent thrombosis did not differ significantly between the two groups. CONCLUSION: Our results show that the adjunctive use of tirofiban reduces the occurrence of PMI and MACE at one year in stable coronary artery disease patients undergoing elective PCI for long lesions with overlapping stent implantation.


Assuntos
Doença da Artéria Coronariana/terapia , Stents Farmacológicos , Intervenção Coronária Percutânea/instrumentação , Inibidores da Agregação Plaquetária/administração & dosagem , Tirosina/análogos & derivados , Idoso , Biomarcadores/sangue , Distribuição de Qui-Quadrado , China , Angiografia Coronária , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/mortalidade , Trombose Coronária/etiologia , Trombose Coronária/prevenção & controle , Creatina Quinase Forma MB/sangue , Feminino , Hemorragia/induzido quimicamente , Humanos , Análise de Intenção de Tratamento , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/prevenção & controle , Razão de Chances , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , Inibidores da Agregação Plaquetária/efeitos adversos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Estudos Prospectivos , Desenho de Prótese , Fatores de Risco , Fatores de Tempo , Tirofibana , Resultado do Tratamento , Tirosina/administração & dosagem , Tirosina/efeitos adversos , Regulação para Cima
5.
Zhongguo Zhong Yao Za Zhi ; 38(15): 2448-52, 2013 Aug.
Artigo em Zh | MEDLINE | ID: mdl-24228533

RESUMO

OBJECTIVE: To compare effects of integrated treatment traditional Chinese medicine and Western medicine (TCM-WM) and simple western medicine on TCM clincal symptoms in the patient of AIDS with pulmonary inflammation. METHOD: A multicenter randomized controlled trials of 164 subjects evaluated the effects of clinical symptoms of AIDS with pulmonary inflammation of TWO regimens: the TCM-WM group (n = 111) and western medicine treatment group (n = 53), while incidence of TCM symptoms in different time points in two groups were analyzed. RESULT: Twenty eight days after treatment, the cured and markedly effective rate of TCM symptoms in the TCM-WM group significantly exceeding that in the western medicine treatment group (cured and markedly effective rate significant efficiency 44.55% vs 20.00%), while the incidence rate for the TCM symptoms of fever and headache in the TCM-WM group was significantly lower than that in western medicine group. CONCLUSION: The integrated treatment of traditional Chinese medicine and Western medicine helps to alleviate the TCM clinical symptoms of AIDS with pulmonary inflammation.


Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Medicina Tradicional Chinesa/métodos , Pneumonia/complicações , Pneumonia/tratamento farmacológico , Feminino , Humanos , Masculino , Análise Multivariada , Resultado do Tratamento
6.
Materials (Basel) ; 15(18)2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36143666

RESUMO

Electric upsetting has been widely employed to manufacture the preformed workpiece of large-scale exhaust valves. The temperature field in the electric upsetting process plays an important role in microstructure evolution and defect formation. In order to uncover the temperature evolution in a larger-scale electric upsetting process, the electric-thermal-mechanical multi-field coupling finite element model was developed to simulate the electric upsetting forming process of Ni80A superalloy. The temperature distribution characteristics and their formation mechanisms under different stages were analyzed systematically. Results indicate that at the preheating stage, the billet temperature increases from 20 °C to 516.7 °C, and the higher temperature region firstly appears at the contact surface between billet and anvil due to the combined effects of contact resistance and volume resistance. With increasing preheating time, the higher temperature region is transferred to the interior of the billet because the contact resistance is reduced with increasing temperature. As for the forming process, the billet is gradually deformed into an onion shape. The highest billet temperature increases to 1150 °C and keeps relatively constant. The high temperature region always appears at the neck of the onion due to the relatively higher current density at this place. It enlarges continuously in the primary stage and intermediate stage, and then decreases at the stable deformation stage. The low temperature regions lie in the contact surface and the outer surface of the onion because a lot of heat is lost to the anvil and surroundings through thermal conduction and radiation. Finally, the established finite element model was verified by an actual electric upsetting experiment. The average relative error between simulated temperatures and experimental ones was estimated as 7.54%. The longitudinal and radial errors between simulated onion shape and the experimental one were calculated as 1.38% and 2.70%, respectively.

7.
Zhonghua Nei Ke Za Zhi ; 50(1): 59-62, 2011 Jan.
Artigo em Zh | MEDLINE | ID: mdl-21418892

RESUMO

OBJECTIVE: To evaluate the therapeutic effect of highly active anti-retroviral therapy (HAART) in treatment-naïve Chinese patients with AIDS, to provide evidences for standardizing HAART. METHODS: Seventy-four treatment-naive AIDS patients were initiated with HAART and followed up regularly for 3 years. The clinical and laboratory data, side effects and drug resistance were observed and analyzed during the follow-up period. RESULTS: Of the 74 patients, 46 were males and 28 were females, with the average age being 42 years. The mean HIV viral load was (2.2 ± 2.0) × 10(5) copies/ml and the baseline mean CD(4)(+)T lymphocyte count was (62 ± 71) cells/µl before treatment. After treatment for 3, 6, 12, 18, 24, 30 and 36 months, the percentage of undetectable HIV viral road (less than 50 copies/ml) was 71.6%, 83.8%, 75.7%, 77.0%, 82.4%, 81.1% and 79.7% respectively, and CD(4)(+)T lymphocyte count ascended to (167 ± 105), (177 ± 129), (238 ± 137), (290 ± 158), (304 ± 191), (331 ± 175) and (352 ± 202) cells/µl. The increase in amplitude of CD(4)(+)T lymphocyte count in different periods examined was different, with the period of 0-3 months post-treatment demonstrating the most obvious augmentation (P < 0.01). The most common adverse reactions were liver function injury (52/74, 70.3%), hyperlipemia (52/74, 70.3%), hematopoietic inhibition of the bone marrow (33/74, 44.6%), peripheral neuritis (32/74, 43.2%) and lipoatrophy (26/74, 35.1%). Clinical drug resistance were found in nine patients and HIV gene mutations were detected in these patients. CONCLUSIONS: Chinese treatment-naive AIDS patients have achieved good virological and immunological response to generic-drug-predominant HAART regimes with low drug resistance, but relatively more side effects.


Assuntos
Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Terapia Antirretroviral de Alta Atividade , Síndrome da Imunodeficiência Adquirida/virologia , Adolescente , Adulto , Idoso , Contagem de Linfócito CD4 , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Carga Viral , Adulto Jovem
8.
Zhonghua Yi Xue Za Zhi ; 91(29): 2055-9, 2011 Aug 09.
Artigo em Zh | MEDLINE | ID: mdl-22093935

RESUMO

OBJECTIVE: To analyze the magnetic resonance imaging (MRI) findings of lesions in the limbic system related structures in general paresis of insane (GPI) patients so as to explore its pathogenesis and provide a new MRI diagnostic method. METHODS: The clinical data and MRI findings of lesions in the limbic system related structures were retrospectively analyzed for a total of 31 GPI patients. The parameters were volume and signal abnormality. RESULTS: On MRI, structural abnormalities were found in amygdaloid body (n = 29), hippocampus (n = 28), insular lobe (n = 24), parahippocampal gyrus (n = 23), lenticular nucleus (n = 23), corpus callosum (n = 20), caudate nucleus (n = 11), hypothalamus (n = 10), anterior nucleus of thalamus (n = 10), cingulate gyrus (n = 8) and thalamus (n = 2). The frequent manifestations were atrophy, swelling, T2 hyperintensity in various structures and T2 hypointensity in lenticular nucleus. CONCLUSION: A frequent involvement of limbic system structures in GPI patients may be related with dementia and other psychiatric symptoms. Swelling and T2 hyperintensity of involved structures may be the characteristic MRI manifestations of GPI.


Assuntos
Sistema Límbico/patologia , Imageamento por Ressonância Magnética , Neurossífilis/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
9.
Zhonghua Yi Xue Za Zhi ; 90(41): 2911-5, 2010 Nov 09.
Artigo em Zh | MEDLINE | ID: mdl-21211396

RESUMO

OBJECTIVE: The objective of this study was to evaluate the performance of 320-row multi-detector CT (MDCT) in the detection and grading of esophageal varices and to evaluate the ability of MDCT in predicting the risk of hemorrhage in comparison with upper endoscopy in patients with portal hypertension. METHODS: A total of 69 patients, with clinically confirmed portal hypertension, underwent epigastric triphasic enhancement scans using 320-row MDCT 1 weeks or less before upper endoscopies were performed. Two blinded abdominal imagers retrospectively interpreted all CT images to detect the presence of esophageal varices and divided EV into large EV (≥ 5 mm) and small EV (< 5 mm). The correlation between CT measurements and endoscopic grading was assessed by kappa values. With endoscopy as standard, the sensitivity, specificity, accuracy, positive predictive value and negative predictive value of the two radiologists in detection of EV were calculated. Correlations between CT measurements of varix size and red color sign were assessed by correlation analysis. RESULTS: Of the total of 69 patients, 56 patients had esophageal varices, 41 had large EV, and 15 had small EV according to the endoscopic findings. MDCT showed an excellent interobserver reliability with regard to the diagnosis of the EV (k = 0.94). Agreement between CT and endoscopy with regard to the grading of EV were excellent (k = 0.77). The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of radiologist 1 in the detection of EV was 95%, 69%, 87%, 93% and 75% respectively; the sensitivity, specificity, accuracy, positive predictive value and negative predictive value of radiologist 2 in the detection of EV was 93%, 77%, 87%, 95% and 71%, respectively. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of the two radiologists in the detection of large EV was 95%, 100%, 97%, 100% and 93%, respectively. CT variceal grading showed a strong correlation with endoscopic grading for both observers (P < 0.01). Correlations between CT measurements of varix size and red color sign were significant in both radiologists with a correlation coefficient r of 0.731 for radiologist 1 (P < 0.01) and 0.718 for radiologist 2 (P < 0.01). CONCLUSION: 320-row MDCT is useful for the detection and grading of EV, and it is useful in evaluation of EV for predicting a risk of hemorrhage.


Assuntos
Varizes Esofágicas e Gástricas/diagnóstico por imagem , Hemorragia/prevenção & controle , Hipertensão Portal/diagnóstico por imagem , Adulto , Idoso , Varizes Esofágicas e Gástricas/patologia , Feminino , Hemorragia/diagnóstico por imagem , Humanos , Hipertensão Portal/patologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X
10.
Zhonghua Yi Xue Za Zhi ; 90(3): 165-8, 2010 Jan 19.
Artigo em Zh | MEDLINE | ID: mdl-20356550

RESUMO

OBJECTIVE: To evaluate the value of low-dose contrast-enhanced 4D DSA acquired from 320-detector row CT on the diagnosis of the hepatic artery complications after liver transplantation. METHODS: 320-detector row CT were performed in fifth patients with liver dynamic enhanced using volume CT body-perfusion protocol, hepatic artery phase images obtained after intravenous injection of 50 ml of contrast at a rate of 6 ml/s were acquired based on 4D DSA. The time-density curve (TDC) of the hepatic artery was delineated. The time to peak, peak contrast enhancement were recorded. The data of artery phase were sent to workstation to reconstruct the hepatic artery with VR, MIP and MPR. RESULTS: The delay mean time and the peak CT value of hepatic artery was 20 (10.0 - 24.2) s and 373 (310 - 440) HU; 4D DSA revealed hepatic artery pseudo-aneurysm (n = 2), and hepatic artery mild stenosis (n = 3), moderate stenosis (n = 4), severe stenosis (n = 1) and occlusion (n = 1). Compensatory circulation was seen in 2 cases. 4 patients were appeared segmental stenosis and hepatoportal arteriovenous fistulas (HPAVF). Hepatic arterial branch are decreased and opened in 9 cases and 4 cases. 4D DSA also displayed other signs including hepatic hemangioma and the splenic artery aneurysms (SAA) and ectasi (n = 1), donor-recipient hepatic artery mismatch (n = 3). CONCLUSION: 4D DSA provided a safe, noninvasive and accurate method for guiding the diagnosis of hepatic artery complication and play an effective role after liver transplantation.


Assuntos
Meios de Contraste , Artéria Hepática/diagnóstico por imagem , Transplante de Fígado/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico por imagem , Adulto Jovem
11.
Zhonghua Gan Zang Bing Za Zhi ; 18(4): 292-6, 2010 Apr.
Artigo em Zh | MEDLINE | ID: mdl-20460051

RESUMO

OBJECTIVE: To evaluate the clinical significance of 320-slice CT hepatic artery images in patients with liver transplantation. METHODS: A total of 58 patients underwent CT scanning by 320-slice scanner after liver transplantation. They were divided into 2 groups according to the concentration of contrast media as follows: Group A (27 cases, 350 mgI/ml iopromide), Group B (31 cases, 370 mgI/ml iopromide). Contrast medium was infused at 6 ml/s, with a total dose of 50 ml. Images were generated by dynamic volume scanning and were processed by 4D digital subtraction angiography (DSA) imaging software. The time-density curve (TDC) of the hepatic artery was delineated. The time to peak, peak contrast enhancement were recorded. The physiological parameters such as body weight and height were analyzed. RESULTS: (1) There were no differences in clinical parameters such as age, sex, height, weight, or BMI between groups. The time to peak of hepatic artery of group A and B was (19.71+/-3.11) s and (20.06+/-3.67) s, and had no significant difference. The maximum peak enhancement of hepatic artery in groups B was higher than that group A (P < 0.05). (2) 4D DSA revealed hepatic artery pseudo-aneurysm (n = 2), and hepatic artery mild stenosis (n = 13), moderate stenosis (n = 5), severe stenosis (n = 9) and occlusion (n = 1), segmental moderate and severe stenosis (n = 4), and compensatory circulation with hepatic artery severe stenosis and occlusion (n = 6). hepatoportal arteriovenous fistulas (HPAVF, n = 12), donor-recipient hepatic artery mismatch (n = 3). Hepatic arterial branch are decreased and opened in 15 cases and 8 cases. CONCLUSION: 320-slice CT hepatic artery images is safe, noninvasive, and accurate technique to evaluate hepatic arterial complications after liver transplantation.


Assuntos
Artéria Hepática/diagnóstico por imagem , Hepatopatias/diagnóstico por imagem , Transplante de Fígado/efeitos adversos , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Idoso , Feminino , Humanos , Hepatopatias/etiologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
Zhonghua Xin Xue Guan Bing Za Zhi ; 38(2): 121-5, 2010 Feb.
Artigo em Zh | MEDLINE | ID: mdl-20398556

RESUMO

OBJECTIVE: Intravascular ultrasound (IVUS) was used to compare the effects on neointimal hyperplasia inhibition between national made Firebird stents and Cypher stents in patients with coronary artery disease. METHODS: From May 2003 to March 2007, 215 patients with 317 native lesions received either Firebird stent (147 lesions of 108 patients, Firebird group) or Cypher stent implantation (138 lesions of 107 patients, Cypher group). Quantitative coronary angiography (QCA) and IVUS were performed at one-year follow-up. RESULTS: The baseline clinical and angiographic characteristics between the two groups were similar, but post procedural minimal lumen diameter was significantly larger in Firebird group than that in Cypher group [(2.88 +/- 0.43) mm vs. (2.78 +/- 0.33) mm, P < 0.05]. follow-up QCA results showed that in-stent late loss [(0.17 +/- 0.29) mm vs. (0.16 +/- 0.27) mm, P > 0.05] and in-segment late loss [(0.18 +/- 0.36) mm vs. (0.20 +/- 0.32) mm, P > 0.05] was similar between Firebird group and Cypher group, while stent cross sectional area (CSA) [(6.99 +/- 2.25) mm(2) vs. (6.46 +/- 1.71) mm(2), P < 0.05], lumen CSA [(6.89 +/- 2.30) mm(2) vs. (6.36 +/- 1.73) mm(2), P < 0.05], stent volume [(162.5 +/- 68.9) m(3) vs. (140.8 +/- 57.9) mm(3), P < 0.01], lumen volume [(160.4 +/- 69.5) mm(3) vs. (138.6 +/- 57.6) mm(3), P < 0.01] and minimal stent CSA [(5.40 +/- 1.85) mm(2) vs. (4.92 +/- 1.43) mm(2), P < 0.05] were larger in Firebird group than those in Cypher group. IVUS analysis showed that there was no significant difference in neointimal hyperplasia volume [(2.09 +/- 5.46) mm(3) vs. (2.23 +/- 6.50) mm(3), P > 0.05] and percentage of volume obstruction [(1.68 +/- 5.84)% vs. (1.59 +/- 4.10)%, P > 0.05] between the two groups. CONCLUSION: Implantation of Firebird stent was associated with low restenosis rate and both Firebird and Cypher stents equally and effectively inhibited neointimal hyperplasia.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Sirolimo/administração & dosagem , Ultrassonografia de Intervenção , Idoso , Stents Farmacológicos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Sirolimo/uso terapêutico
13.
Zhong Yao Cai ; 33(2): 210-3, 2010 Feb.
Artigo em Zh | MEDLINE | ID: mdl-20575411

RESUMO

OBJECTIVE: To study the alkaloids from Corydalis impatiens. METHODS: The alkaloids were isolated and purified by chromatography and their structures were identified by spectral data and others methods. RESULTS: Seven alkaloids were isolated and identified as bicuculline(1), ochotensine(2), ochotensimine(3), ochrobirine(4), tetrahydrothalifendine(5), norochotensimine(6), N-methylactinodaphnine(7). CONCLUSION: All these compounds are isolated from this plant for the first time.


Assuntos
Alcaloides/isolamento & purificação , Corydalis/química , Dioxolanos/isolamento & purificação , Plantas Medicinais/química , Alcaloides/química , Bicuculina/química , Bicuculina/isolamento & purificação , Cromatografia em Camada Fina , Dioxolanos/química , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Raízes de Plantas/química
14.
Circ J ; 73(12): 2236-43, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19822979

RESUMO

BACKGROUND: The efficacy of partial vs full coverage for tandem lesions in the culprit vessel during primary percutaneous coronary intervention (PCI) after ST-elevation myocardial infarction (STEMI) was compared in the present study. METHODS AND RESULTS: The 76 patients with STEMI and tandem lesions in the culprit vessel were randomized to receive stent implantation for an occluded/culprit lesion only (partial group) or complete coverage of lesions (full group). After PCI, patients in the partial group had more complete ST-segment resolution (STR) at 90 min (60.5% vs 28.9%, P=0.006), Thrombosis In Myocardial Infarction (TIMI) flow grade 3 (68.4% vs 28.9%, P=0.001), and myocardial blush grade 3 (42.1% vs 15.8%, P=0.04) than those in the full group. At 6 months, the major adverse cardiac events-free survival rate did not differ significantly between groups, but left ventricular (LV) ejection fraction was improved in the partial group. Multivariate analysis revealed pre-procedural TIMI flow grade >1 and door-to-balloon time <90 min were positively associated with complete STR at 90 min, whereas full coverage for tandem lesions was an independent factor for poor STR (odds ratio 2.58, 95% confidence interval 1.08-5.42, P=0.03). CONCLUSIONS: For acute STEMI patients with tandem lesions in the culprit vessel, primary stenting for the occluded lesion only is beneficial in improving myocardial perfusion and LV function.


Assuntos
Angioplastia Coronária com Balão/métodos , Infarto do Miocárdio/terapia , Idoso , Angioplastia Coronária com Balão/efeitos adversos , Angioplastia Coronária com Balão/instrumentação , Angioplastia Coronária com Balão/mortalidade , Circulação Coronária , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/fisiopatologia , Razão de Chances , Estudos Prospectivos , Desenho de Prótese , Recuperação de Função Fisiológica , Recidiva , Medição de Risco , Fatores de Risco , Stents , Volume Sistólico , Fatores de Tempo , Resultado do Tratamento , Função Ventricular Esquerda
15.
Cardiology ; 112(3): 191-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18682662

RESUMO

OBJECTIVE: The RIFT study aimed to observe the impact of renal insufficiency (RI) on the incidence of stent thrombosis (ST) after percutaneous coronary intervention. METHODS: The RIFT study enrolled 1,174 patients undergoing revascularization exclusively with sirolimus-eluting stents. The occurrence of ST and major adverse cardiac events were compared between patients with (n = 309) and without (n = 865) RI, and independent predictors of ST were also identified. RESULTS: During follow-up (mean 18.9 +/- 9.2 months), the rate of ST was significantly higher in patients with than without RI [5.5% (n = 17) vs. 1.7% (n = 15), p < 0.001], and the presence of severe RI (estimated glomerular filtration rate <30 ml/min.1.73 m(2)) was an independent predictor of ST (odds ratio = 4.5, 95% confidence interval 1.4-15, p = 0.011). In patients with RI and diabetes or left ventricular ejection fraction (LVEF) <50%, the incidence of ST was significantly increased [13.0% (n = 10) vs. 3.6% (n = 7), p = 0.010; 11.6% (n = 8) vs. 1.9% (n = 3), p = 0.004, respectively] compared to those with diabetes or LVEF <50% alone. The influence of RI on ST was not significant in patients with multivessel disease, calcified or bifurcation lesions, and target lesion revascularization. CONCLUSIONS: These findings substantiate the importance of long-term antiplatelet therapy for patients with RI after drug-eluting stent implantation.


Assuntos
Angioplastia Coronária com Balão , Stents Farmacológicos/efeitos adversos , Imunossupressores/administração & dosagem , Insuficiência Renal/epidemiologia , Sirolimo/administração & dosagem , Trombose/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/terapia , Intervalo Livre de Doença , Stents Farmacológicos/estatística & dados numéricos , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/administração & dosagem , Valor Preditivo dos Testes , Estudos Prospectivos , Fatores de Risco , Índice de Gravidade de Doença , Trombose/prevenção & controle
16.
Zhonghua Zhong Liu Za Zhi ; 31(9): 691-6, 2009 Sep.
Artigo em Zh | MEDLINE | ID: mdl-20021867

RESUMO

OBJECTIVE: To investigate the manifestation and diagnostic value of multislice spiral CT (MSCT) and MRI imaging in detection of tumor recurrence after liver transplantation for hepatocellular carcinoma (HCC). METHODS: The clinical data of 161 consecutive HCC patients who underwent orthotopic liver transplantation were retrospectively reviewed. Twenty-nine HCC patients were classified by pTNM according to the "Pittsburgh criteria". MSCT and MRI findings of tumor recurrence after liver transplantation were evaluated retrospectively in 29 stage II-IVb HCC patients. The recurrence site and relapse interval between liver transplantation and recurrence were analyzed. RESULTS: Lung tumor recurrence were found in 21 cases, presented as cotton-like lesions in a diameter of 2 - 3 cm, with a clear margin and homogeneous density. Pleural tumor recurrence was detected in 4 cases. Liver tumor recurrence were found in 9 cases, which can be divided into four subtypes: multinodular in 4 cases, diffuse lesion in 2 cases, huge mass in 2 cases, and uninodular in 1 case. Two cases showed tumor thrombus in the inferior vena cava and portal vein. Lymph node tumor recurrence was found in 9 cases, presented as multiple nodules at hepatic hilum, lesser peritoneal sac, posterior mediastinum, retroperitoneum, or around pancreatic head, and accompanied with merging and necrosis in one case. Bone tumor recurrence were found as osteolytic destruction in 4 cases, and accompanied with adjacent soft-tissue mass in 2 cases. The recurrence sites of the 29 cases were as following: lung (21 cases, 72.4%), liver (9 cases, 31.0%), lymph nodes (9 cases, 31.0%), bone (4 cases, 13.8%) and other sites (3 cases, 10.3%). Lung tumor recurrence was found in all the 10 stage IVb patients with tumor recurrence after liver transplantation, significantly more frequent than that in stage IVa patients (P = 0.023). After liver transplantation, all 25 patients with stage III approximately IVb HCC developed recurrence within one year, but in the 4 cases with stage II HCC at one year later (P = 0.009). CONCLUSION: The results of our study show that in hepatocellular carcinoma patients after liver transplantation, the lung and pleura are the most frequent site of recurrence, followed by liver, lymph node and bone as the second and third sites. The Stage IVb hepatocellular carcinoma should be regarded as a contradiction for liver transplantation due to rapid recurrence. Tumor recurrence occurs later in stage II HCC than in stage III approximately IVb patients. MSCT and MRI are of significant importance in diagnosis and formulating operation plan in HCC patients with recurrence after liver transplantation.


Assuntos
Carcinoma Hepatocelular/secundário , Neoplasias Hepáticas/diagnóstico , Transplante de Fígado , Neoplasias Pulmonares/secundário , Tomografia Computadorizada Espiral/métodos , Adulto , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/diagnóstico por imagem , Metástase Linfática , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/diagnóstico por imagem , Células Neoplásicas Circulantes , Neoplasias Pleurais/diagnóstico , Neoplasias Pleurais/diagnóstico por imagem , Neoplasias Pleurais/secundário , Estudos Retrospectivos
17.
Zhonghua Xin Xue Guan Bing Za Zhi ; 37(1): 30-4, 2009 Jan.
Artigo em Zh | MEDLINE | ID: mdl-19671348

RESUMO

OBJECTIVE: The impact of late incomplete stent apposition (ISA) post sirolimus eluting stent (SES) implantation in patients with acute coronary syndrome (ACS) on long-term clinical outcomes remains controversial. The aim of the present study was to evaluate the association between late ISA and clinical outcomes in patients with ACS compared with that with stable angina (SA). METHODS: From February 2005 to March 2007, 54 ACS patients and 83 SA patients were enrolled in this study, late ISA was determined by means of three-dimensional volumetric intravascular ultrasound (IVUS) analyses one year after SES implantation and clinical outcomes one year post IVUS were obtained in these patients. RESULTS: In 219 treated lesions of the 137 patients, late ISA was documented in 25 lesions in 16 patients (20 ISA in 12 ACS patients vs. 5 ISA in 4 SA patients, P<0.001). Though lumen area in reference and stented segment, neointimal hyperplasia (NIH) area and percentage of NIH in stented segment, and external elastic membrane (EEM) area in reference segment were similar between two groups, EEM area in stented segment [(15.34+/-5.44) mm2 vs. (13.83+/-4.51) mm2, P=0.026], stented/reference segment EEM area ratio (1.13+/-0.22 vs. 1.02+/-0.18, P<0.001), plaque and media area [(8.43+/-3.93) mm2 vs. (7.01+/-2.93) mm2, P=0.002] was significantly lager in ACS group than that in SA group. Multivariable logistic analysis showed that ACS (OR 6.477 with 95% CI from 2.297 to 18.263, P<0.001) and stent length>or=23 mm (OR 3.680 with 95% CI from 1.181 to 11.469, P=0.025) were main independent factors of occurrence of late ISA. Incidence of main adverse cardiac events (MACE) one year post IVUS was similar between the two groups. CONCLUSION: Compared with patients with SA, ACS patients had larger stented segment EEM area, plaque and media area as well as increased incidence of ISA. However, the incidence of MACE was similar in ACS and SA patients one year after IVUS.


Assuntos
Síndrome Coronariana Aguda/terapia , Stents Farmacológicos , Sirolimo/administração & dosagem , Síndrome Coronariana Aguda/patologia , Idoso , Angina Pectoris/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento
18.
Zhong Yao Cai ; 32(4): 511-4, 2009 Apr.
Artigo em Zh | MEDLINE | ID: mdl-19645233

RESUMO

OBJECTIVE: To study the chemical constituents of Swertia mussotii. METHODS: The constituents were isolated by various column chromatography methods, and their structures were identified by physico-chemical properties and spectral analysis. RESULTS: Eleven compounds were isolated and identified as 1,3, 8-trihydroxy-7-methoxyxanthone (I), 2,8-dihydroxy-1,6-dimethyoxyxanthone (II), 1,8-dihydroxy-2,6-dimethoxyxanthone (III), 1,2,8-trimethoxyxanthone (IV), 1,3,5,6-tetrohyroxyxanthone (V), 1,8-dihydroxy-3,7-dimethoxyxanthone (VI), beta-daucosterol (VII), clerosterol 3beta-O-[6'-o-hydro-benzene-beta-D-glucoside] (VIII), ursolicacid (IX), 3beta,28-dihydroxylup-20 (29) -ene (X), erythrocentaurin (XI). CONCLUSION: Compounds VIII, IX and X are isolated from Swertia mussotii for the first time.


Assuntos
Plantas Medicinais/química , Swertia/química , Triterpenos/isolamento & purificação , Xantonas/isolamento & purificação , Estrutura Molecular , Controle de Qualidade , Sitosteroides/química , Sitosteroides/isolamento & purificação , Triterpenos/química , Xantonas/química
19.
Coron Artery Dis ; 19(4): 271-7, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18480672

RESUMO

BACKGROUND: There is continued debate as to whether a combined reperfusion regimen with platelet glycoprotein IIb/IIIa inhibitor-tirofiban provides additional benefit in optimal myocardial reperfusion for patients with acute ST-segment elevation myocardial infarction (STEMI). This study was conducted to investigate the clinical benefits of adjunctive tirofiban therapy combined with primary percutaneous coronary intervention (PCI) in patients with STEMI. METHODS: One hundred and seventy-two consecutive patients with STEMI presented within 12 h of symptoms were randomly allocated to primary PCI combined with early (upstream group, n=57) or late administration of tirofiban (downstream group, n=57) or primary PCI treatment alone (control group, n=58). Clinical characteristics, angiographic findings, and in-hospital outcomes were compared between groups, as well as left ventricular ejection fraction (LVEF) and major adverse cardiac events (MACE, including death, reinfarction and target vessel revascularization) at 30-day and 6-month clinical follow-up. RESULTS: Despite comparable baseline clinical features among three groups, angiographic and procedural characteristics and outcomes differed significantly between patients receiving tirofiban treatment and controls, with respect to preprocedural (upstream: 28.1%, downstream: 7.0%, control: 5.2%, P<0.001) and postprocedural thrombolysis in myocardial infarction (TIMI) grade 3 flow of infarct-related artery (98.2, 94.7, 86.2%, P=0.03), TIMI myocardial perfusion grade 3 (75.4, 70.2, 53.4%, P=0.03), corrected TIMI frame count (20.4+/-5.0, 23.1+/-5.3, 32.2+/-6.7, P<0.001), resolution of the sum of ST-segment elevation (6.16+/-1.21, 6.02+/-1.09, 4.53+/-2.65 mm, P<0.001), peak value of creatine kinase-MB (218.0+/-72.5, 224.2+/-69.4, 255.3+/-77.0 ng/ml, P=0.02) and troponin I (76.0+/-21.5, 79.8+/-18.7, 86.4+/-11.0 ng/ml, P=0.007), and average hospital stay (10.6+/-5.4, 12.6+/-4.7, 14.5+/-6.5 days, P=0.001). The MACE rate at 30 days (3.5, 5.3, 15.5%, P=0.04) was reduced and LVEF (0.51+/-0.07, 0.50+/-0.07, 0.47+/-0.08, P=0.008) was higher in upstream and downstream groups than in controls. At 6-month follow-up, the MACE rate was not significantly different among groups (7.0, 8.8, 17.2%, P=0.17), but LVEF in upstream and downstream groups was significantly improved (0.59+/-0.06, 0.57+/-0.07, 0.54+/-0.07, P<0.001). Subgroup analysis demonstrated a statistically significant difference between upstream and downstream groups in preprocedural TIMI grade 3 flow (P=0.003) and postprocedural corrected TIMI frame count (P=0.007), which resulted in a shortened hospital stay (P=0.04), reduction of MACE rate at 30-day and 6-month follow-up by 34 and 20%, respectively. Multivariate logistic analysis revealed that age more than 65 years [odds ratio (OR)=3.42, P<0.01], tirofiban therapy (OR=0.56, P<0.05) and LVEF less than 0.5 during hospitalization (OR=2.56, P<0.01) were major independent predictors of MACE at 6-month clinical follow-up. No significant difference in hemorrhagic complications among three groups was noted (upstream: 10.5%, downstream: 12.3%, control: 6.9%, P=0.61). CONCLUSION: This prospective study indicates that adjunctive tirofiban therapy for patients with STEMI who undergo primary PCI can significantly improve reperfusion level in the infarct area, clinical outcomes at 30-day and 6-month follow-up, especially with upstream tirofiban therapy, and is safe.


Assuntos
Angioplastia Coronária com Balão , Infarto do Miocárdio/terapia , Inibidores da Agregação Plaquetária/administração & dosagem , Tirosina/análogos & derivados , Idoso , Idoso de 80 Anos ou mais , Quimioterapia Adjuvante , Esquema de Medicação , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Reperfusão Miocárdica , Estudos Prospectivos , Tirofibana , Tirosina/administração & dosagem
20.
Chin Med J (Engl) ; 121(17): 1670-4, 2008 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-19024097

RESUMO

BACKGROUND: Multiple randomized clinical trials have demonstrated that drug eluting stents can significantly reduce the rates of restenosis and subsequent adverse events across lesion and patient. We investigated the medium term clinical efficacy and safety of Firebird sirolimus eluting stent (SES) in coronary artery disease. METHODS: The sample was 509 consecutive patients with coronary artery disease (CAD) who were treated by Firebird SES and finished three-year clinical follow-up. The occurrences of major adverse cardiac events (MACE) and Academic Research Consortium defined stent thrombosis (ST) were evaluated in patients with and without diabetes mellitus. RESULTS: Three hundred and thirty three patients (65.4%) were treated by Firebird SES by off label indications. Angiographic success was achieved in 98.3% of the lesions. MACE and target vessel revascularization rates at 6-month, 1 year's and 3 years' clinical follow-up were 2.4% and 1.4%, 4.1% and 2.8%, 7.9% and 5.1%, respectively. The cumulative 3-year MACE free survival rate was 92.1%. After 3 years, DM patients had significantly higher rates of MACE (13.7% vs 6.4%, P < 0.05) and TVR (9.8% vs 4.0%, P < 0.05) and the cumulative MACE free survival rate was very significantly lower in the DM group (86.4% vs 93.6%, P < 0.05). ST occurred in 7 patients (1.4%) at the end of 3 years' follow-up, 5 of them had definite ST with 4 cases presenting with myocardial reinfarction and 1 with unstable angina, the other 2 with probable ST had reinfarction in the stented coronary territory without angiographic follow-up. There was no difference in occurrence of ST between off label (1.5%) and on label groups (1.1%, P = 0.07). CONCLUSIONS: In daily practice, about 2/3 of patients were treated by Firebird SES by off label indications. Medium term clinical follow-up of 3 years indicated CAD patients treated by Firebird SES had a low MACE and acceptable ST rate. DM patients had higher rates of adverse events and than non DM.


Assuntos
Angioplastia Coronária com Balão , Stents Farmacológicos , Sirolimo/administração & dosagem , Adulto , Idoso , Angioplastia Coronária com Balão/efeitos adversos , Aspirina/uso terapêutico , Angiografia Coronária , Complicações do Diabetes/etiologia , Stents Farmacológicos/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sirolimo/efeitos adversos , Trombose/etiologia
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