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1.
ACS Nano ; 16(9): 14379-14389, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36095242

RESUMO

Two-dimensional (2D) lamellar membranes, with highly ordered nanochannels between the adjacent layers, have revealed potential application prospects in various fields. To separate gases with similar kinetic diameters, intercalation of a functional liquid, especially an ionic liquid (IL), into 2D lamellar membranes is proved to be an efficient method due to the capacity of imparting solubility-based separation and sealing undesired defects. Stable immobilization of a high content of liquid is challenging but extremely required to achieve and maintain high separation performance. Herein, we describe the intercalation of a typical IL, 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4]), into the ionized nanochannels of sulfonated MXene lamellar membranes, where the sulfonate groups are anchored onto MXene nanosheets through a facile method based on metal-catechol chelating chemistry. Thanks to the intrinsic benefits of MXene as building blocks and the decorated sulfonate groups, the optimal membrane possesses adequate interlayer spacing (∼1.8 nm) and high IL uptake (∼47 wt %) and therefore presents a CO2 permeance of 519 GPU and a CO2/N2 selectivity of 210, outperforming the previously reported liquid-immobilized lamellar membranes. Moreover, the IL loss rate of the membrane within 7 days at elevated pressure (5 bar) is measured to be significantly decreased (from 43.2 to 9.0 wt %) after growing sulfonate groups on the nanochannel walls, demonstrating the excellent IL storage stability.

2.
Front Chem ; 8: 58, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32117883

RESUMO

Dual-filler MMMs have attracted special interests in recent years because of the possibility of producing synergetic effect. This study is aimed at exploring the underlying synergy between two-dimensional (2D) nanosheets and a non-2D filler in mixed matrix membranes for gas separation. MXene or graphene oxide (GO) as typical nanosheet filler is selected to be in pair with a non-2D filler, SiO2 or halloysite nanotubes (HNTs), with Pebax as the polymer matrix. In this way, four pairs of binary fillers are designed and the corresponding four groups of MMMs are fabricated. By tuning the mass ratio of binary fillers, synergetic effect is found for each group of MMMs. However, the two 2D fillers found different preferential non-2D partners. GO works better with HNTs than SiO2, while MXene prefers SiO2 to HNTs. To be noted, GO/HNTs renders the membranes the maximum enhancement of CO2 permeability (153%) and CO2/N2 selectivity (72%) compared to Pebax control membrane, while each of them as single filler only brought about very limited enhancement of CO2 separation performance. The possible mechanisms are thoroughly discussed in terms of filler dispersion, nanosheet flexibility, and the tortuosity and connectivity of the surface diffusion pathways along nanosheets.

3.
Exp Ther Med ; 12(1): 262-266, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27347047

RESUMO

Post-transplant lymphoproliferative disorder (PTLD) is one of the most frequent secondary malignancies that can follow immunosuppressive therapy for solid organ transplantation, and may result in severe morbidities and even mortality. A middle-aged Han Chinese patient, prescribed with immunosuppressive cyclosporine and prednisone, developed PTLD that manifested as a painless cervical lymph node enlargement, 12 years following heart transplantation. Histology revealed monomorphic B-cell PTLD (diffuse large-cell lymphoma); as a result the immunosuppressive regimen of the patient was changed to tacrolimus and mycophenolate mofetil. In addition, the patient was changed to 6-cycle rituximab with a modified mini-CHOP (R-mini-CHOP) regimen for induction, and 8-cycle quarterly rituximab treatment and maintenance therapy. R-mini-CHOP therapy was well tolerated, and no allograft rejection occurred. The patient exhibited clinical remission as demonstrated by the results of the positron emission tomography-computed tomography at the 5-year follow-up visit following R-mini-CHOP therapy. In conclusion, R-mini-CHOP therapy following reduced immunosuppression is effective and safe for the treatment of late-onset PTLD following heart transplantation.

4.
ASAIO J ; 60(6): 681-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25232770

RESUMO

Although continuous perfusion of donor hearts for preservation during transportation has been widely applied, intermittent perfusion has been suggested as an alternative. The aim of this study was to identify the optimal intermittent perfusion protocol by investigating the effects of perfusion volume on endothelial and inflammatory marker expression by the coronary artery. Donor porcine hearts were perfused with various volumes of Celsior solution supplemented with diazoxide (50, 100, 150, 200, and 250 ml) every 2 h for 30 min each for a 10 h period. The effects on cardiomyocytes and vascular endothelial cell morphology and marker expression were compared to the immersion control group. Whereas an incomplete endothelial cell layer with disorganized connective tissue was observed in the control and 50, 100, and 150 ml intermittent perfusion groups, transmission electron microscopic analysis revealed a complete endothelial cell layer in the intima with an organized subendothelium. A perfusion volume-dependent increase in eNOS expression that coincided with a decrease in ET-1, ICAM-1, vWF, and P-selectin expression was detected (all p < 0.01). Intermittent perfusion with 200 ml of Celsior solution every 2 h conferred protective effects simultaneously to the coronary arteries and myocardium on the porcine donor heart over a clinically relevant preservation period.


Assuntos
Vasos Coronários/metabolismo , Transplante de Coração , Coração , Miocárdio/metabolismo , Preservação de Órgãos/métodos , Animais , Biomarcadores/metabolismo , Soluções Cardioplégicas , Dissacarídeos , Eletrólitos , Endotelina-1/genética , Endotelina-1/metabolismo , Endotélio/metabolismo , Glutamatos , Glutationa , Histidina , Mediadores da Inflamação/metabolismo , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Masculino , Manitol , Modelos Animais , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Soluções para Preservação de Órgãos , Selectina-P/metabolismo , Perfusão , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Suínos , Porco Miniatura , Doadores de Tecidos , Fator de von Willebrand/metabolismo
5.
Cell Biochem Biophys ; 70(2): 1401-5, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24908265

RESUMO

To analyze the efficacy of different surgical methods in treating palmar hyperhidrosis and the compensatory hyperhidrosis after surgery and to observe the efficacy of "Energy-boosting and Yin-nourishing anti-perspirant formula" on postsurgical hyperhidrosis patients. Two-hundred patients were randomly assigned to groups A (Chinese and Western medicine, T4 transection plus "Energy-boosting and Yin-nourishing anti-perspirant formula") and B (Western medicine, T4 transection). The surgical efficiency, recurrence rate, compensatory hyperhidrosis, and the long-term life quality were compared. Another 100 cases (group C, T2 transection) were analyzed as a control group. After surgery, the palmar hyperhidrosis and armpit sweating were relieved in all the three group patients and in 34 % of patients combined with plantar hyperhidrosis, the symptoms were relieved. Transient palmar hyperhidrosis was found in three cases at day 2 to day 5 postoperatively. One case of Horner's syndrome and one case recurrence were found in group C patients. The compensatory sweating of various degrees occurred in all the three groups. There were 25, 24, and 43 cases in groups A, B, and C, respectively. There is a significant difference between groups C, A, and B. The compensatory sweating in 13 cases of group A and four cases of group B had different degrees of improvement in the follow-up 6 months after surgery. There is a significant difference. Thoracoscopic bilateral T4 sympathetic chain and the Kuntz resection are the optimized surgical treatments for the palmar hyperhidrosis. "Energy-boosting and Yin-nourishing anti-perspirant formula" is effective in treating the postoperative compensatory sweating.


Assuntos
Hiperidrose/cirurgia , Medicina Tradicional Chinesa/métodos , Adolescente , Adulto , Temperatura Corporal , Humanos , Hiperidrose/fisiopatologia , Hiperidrose/terapia , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Resultado do Tratamento , Adulto Jovem
6.
Biochem Biophys Res Commun ; 344(1): 214-20, 2006 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-16630577

RESUMO

The prevention of hyperacute rejection (HAR) triggered by interaction between the human natural antibody and xenoreactive antigenic epitope (Gal-alpha1, 3Gal) present on pig cells is the key to success in pig-to-human xenotransplantation. The phage display technology offers an effective strategy for screening peptides which can interact with the anti-Gal antibody to block alpha-Gal antigen binding site. Two peptide libraries, linear 7 peptide library and C7C library, were panned on the anti-B monoclonal antibody which has the characteristic of binding to the alpha-Gal antigenic epitope. After four rounds of panning, 22 positive phage clones were selected. Highly homologous sequence PT and STL existed among these selected peptides. Stachyose competitive ELISAs revealed that these peptides specifically bound to alpha-Gal antigen binding site. Eight peptide mimics of alpha-Gal antigenic epitope could inhibit the agglutination of pig red blood cells mediated by human sera in a dose-dependent manner. These results demonstrated that the selected peptides can mimic the conformational structure of alpha-Gal antigenic epitope and have the therapeutic potential in xenotransplantation.


Assuntos
Dissacarídeos/imunologia , Epitopos Imunodominantes/imunologia , Mimetismo Molecular/imunologia , Peptídeos/imunologia , Peptídeos/isolamento & purificação , Transplante Heterólogo/imunologia , Aglutinação , Sequência de Aminoácidos , Animais , Anticorpos Anti-Idiotípicos/imunologia , Anticorpos Monoclonais/imunologia , Ligação Competitiva , Ensaio de Imunoadsorção Enzimática , Rejeição de Enxerto/prevenção & controle , Testes de Hemaglutinação , Humanos , Dados de Sequência Molecular , Biblioteca de Peptídeos , Peptídeos/uso terapêutico , Suínos/imunologia
7.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 34(4): 331-8, 2005 07.
Artigo em Chinês | MEDLINE | ID: mdl-16059981

RESUMO

OBJECTIVE: To investigate whether the mitochondrial ATP-sensitive potassium channel (mitoK(ATP)) opener diazoxide as an additive to cardioplegia solution could enhance myocardial protection during hypothermic preservation of the rat heart. METHODS: The Langendorff model of isolated rat heart was used. After equilibrium, the hearts were stored in Celsior cardioplegia solution at 4 degree with or without supplement of diazoxide for 3 or 8 h followed by 60 minutes reperfusion. The recovery of cardiac contractile function, myocardial enzyme leakage in the coronary effluent, and myocardial water content were determined. The myocardial ultrastructure was also observed. RESULT: (1) Treatment of diazoxide improved the recovery of left ventricular developed pressure and decreased the leakage of myocardial enzymes, lactate dehydrogenase (LDH) and creatine kinase (CK), at the 2nd and 4th minute of reperfusion of rat heart after hypothermic preservation for 3 h. (2) After hypothermic preservation for 8 h, diazoxide improved the recovery of left ventricular developed pressure and decreased the leakage of myocardial enzymes (LDH, CK and glutamic oxalic transaminase) during reperfusion. Moreover, left ventricular end-diastolic pressure was significantly lower in diazoxide-treated hearts than that of hearts in Celsior solution. (3) Diazoxide significantly decreased the water content of myocardium and increased coronary flow of the hearts compared with those in control after hypothermic preservation for 8 h. (4) Impairment of myocardial ultrastructure after 8 h hypothermic preservation was alleviated in hearts treated with 30 mol/L diazoxide. (5) The cardiac effects of 30 mol/L diazoxide were attenuated by a mitoK(ATP) blocker 5-hydroxydecanoate (100 micromol/L). CONCLUSION: Diazoxide as a supplementation in cardioplegia solution could enhance myocardial protection during hypothermic heart preservation via opening of mitochondrial K(ATP) channel.


Assuntos
Criopreservação , Diazóxido/farmacologia , Coração , Soluções para Preservação de Órgãos/farmacologia , Preservação de Órgãos , Canais de Potássio/efeitos dos fármacos , Animais , Soluções Cardioplégicas , Masculino , Ratos , Ratos Sprague-Dawley
8.
Sheng Li Xue Bao ; 56(5): 632-8, 2004 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-15497046

RESUMO

Prolongation of the duration of heart preservation in vitro is very important in clinical heart transplantation. Previous studies have shown that mitochondrial ATP-sensitive potassium channel (mitoK(ATP)) plays an important role in cardioprotective effect. The purpose of this study was to assess whether the mitoK(ATP) opener diazoxide as an additive to cardioplegia solution could enhance myocardial protection during long-term hypothermic preservation of the rat heart. Langendorff model of isolated rat heart was used. After 30 min stabilization of perfusion, the hearts were stored in Celsior cardioplegia solution at 4 degrees C with (15, 30 and 45 micromol/L) or without diazoxide, a mitoK(ATP) channel opener, for 10 h followed by 60 min reperfusion. The recovery of cardiac contractile function, myocardial enzyme leakage in the coronary effluent, and myocardial water content were determined. The myocardial ultrastructure was also observed. We found that: (1) Diazoxide treatment improved the recovery of left ventricular developed pressure and +/-dp/dt(max) dose-dependently. Left ventricular end-diastolic pressure was significantly lower in diazoxide-treated hearts than that of hearts in Celsior solution after hypothermic preservation for 10 h. (2) Diazoxide at 30 and 45 micromol/L significantly decreased the water content of myocardium and increased coronary flow of the hearts compared to those in control. (3) The leakage of myocardial enzymes (lactate dehydrogenase, creatine kinase and glutamate-oxaloacetate transaminase) in the coronary effluent was significantly reduced in diazoxide-treated hearts. (4) Impairment of myocardial ultrastructure after 10 h hypothermic preservation was alleviated in hearts treated with 30 micromol/L diazoxide. (5) The cardiac effects of 30 micromol/L diazoxide were attenuated by a mitoK(ATP) blocker 5-hydroxydecanoate (5-HD, 100 micromol/L). These results indicate that diazoxide as a supplementation in cardioplegia solution could enhance myocardial protection during long-term hypothermic heart preservation via opening of mitochondrial K(ATP) channel.


Assuntos
Criopreservação , Diazóxido/farmacologia , Coração , Soluções para Preservação de Órgãos/farmacologia , Canais de Potássio/metabolismo , Animais , Técnicas In Vitro , Masculino , Mitocôndrias Cardíacas/metabolismo , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
9.
Zhonghua Yi Xue Za Zhi ; 84(11): 885-7, 2004 Jun 02.
Artigo em Chinês | MEDLINE | ID: mdl-15329269

RESUMO

OBJECTIVE: To observe the effects of heart transplantation. METHODS: Twelve patients undergoing orthotopic heart transplantation, one of which underwent combined heart and kidney transplantation (HKT), from June 1997 to June 2002 were followed up to observe the complications, work ability, life quality and psychic status. RESULTS: One of the 12 patients died of acute rejection and one died of acute renal failure during perioperative period. Ten cases (83.3%) survived the operation. Then one of the 10 patients died of acute rejection due to stopping Cellcept 7 months after operation; and the other 9 patients had lived well for 1 to 9 years, of which one recipient undergoing HKT survived for nearly 3 years. One year after operation the 9 patients showed class I heart function (NYHA), and all resumed their original work. One patient suffered from schizophrenia 1 week after operation. After the operation every year all cases were to receive coronary angiography with the results showing thinner coronary artery and less lateral branches, and myocardium, emission computed tomography (ECT) scanning that revealed local ischemia in anterior or posterior myocardium in 2 cases 4 and 5 years after respectively, however, no symptom of coronary artery disease was seen in all patients. Two cases, including the one receiving HKT, had symptoms of diabetes mellitus. Two patients thoracotomy during the perioperative period because of cardiac tamponade or too much blood drainage. All cases suffered from right heart failure, mouth ulcer and hypertension due to taking CsA and they had to take antihypertension drug to control their blood pressure. No malignant tumor had been found. CONCLUSION: Heart transplantation is an effective treatment for end-stage dilated cardiomyopathy. But many complications may follow. Some of them may endanger patients' life, and others may affect the quality of life. To trace the patients closely and deal with various complications in time will improve the effect of cardiac transplantation.


Assuntos
Tolerância ao Exercício , Transplante de Coração/efeitos adversos , Qualidade de Vida , Adolescente , Adulto , Cardiomiopatia Dilatada/cirurgia , Feminino , Seguimentos , Rejeição de Enxerto , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/epidemiologia , Isquemia Miocárdica/etiologia , Complicações Pós-Operatórias/epidemiologia , Inquéritos e Questionários , Resultado do Tratamento
10.
Biochem Biophys Res Commun ; 308(1): 19-22, 2003 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-12890473

RESUMO

The carbohydrate of Gal-alpha1,3-Gal is thought to be the major antigenic epitope present on pig vascular endothelium. The peptides that mimic the binding of antigenic epitope (Gal-alpha1,3-Gal) to lectin BS-I-B4 were identified from screening a filamentous phage-displayed random library. A phage bearing the peptide NCVSPYWCEPLAPSARA has been identified to bind the lectin strongly. Melibiose was able to inhibit the binding of the human natural anti-alpha Gal antibody to the peptide competitively. Our experiments show that the peptide mimetic of Gal-alpha1,3-Gal is able to inhibit the agglutination of pig RBCs by human natural antibody or lectin BS-I-B4. The peptide inhibitor of human natural antibodies may prove useful in pig-to-human xenotransplantation.


Assuntos
Anticorpos/imunologia , Galactose/química , Mimetismo Molecular , Sequência de Aminoácidos , Sequência de Bases , Primers do DNA , Testes de Hemaglutinação , Humanos , Melibiose/química , Dados de Sequência Molecular
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