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1.
J Org Chem ; 89(8): 5320-5327, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38554091

RESUMO

Electromagnetic mill (EMM)-promoted solid-state cascade Heck-type cyclization/decarboxylative coupling of propiolic acid with (Z)-1-iodo-1,6-diene derivate was demonstrated. The reaction was realized via palladium catalysis, which is solvent-free and involves no additional heating. The collision between ferromagnetic rods could not only be a favor to the mixing between the solid substrates and the catalyst system, but also the thermogenic action could accelerate this transformation. More importantly, this EMM strategy realized multiple bond construction under mechanochemical conditions in one pot.

2.
Opt Express ; 31(1): 248-264, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36606964

RESUMO

An instrument named as Volume Scattering and Attenuation Meter (VSAM) is presented. The VSAM can simultaneously measure the attenuation coefficient and the volume scattering function (VSF) from 10° to 170° with an interval of 10° at 659 nm. Using ultrapure water and NCRM-traceable polystyrene microsphere beads, the VSAM was calibrated, and the conversion factor χbθ for estimating the backscattering coefficient from the backward VSF was obtained based on Mie theory in the laboratory. For χbθ, the average relative deviation was no more than 7.77% in the range of 100°-160° between the modeled result based on VSAM and the theoretical result by Boss. Subsequently, the VSAM and ECO-VSF3 were deployed in situ in Zhanjiang Bay. The backscattering coefficient and VSF at the same angles measured by the two instruments were quite consistent. Some remarkable changes in the shape and magnitude of the VSF profile at different stations were found, with land-based pollutants composing an important suspicious source of these changes.

3.
Opt Express ; 31(26): 43771-43789, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38178466

RESUMO

The vertical distribution of the diffuse attenuation coefficient K(z, λ) is critical for studies in bio-optics, ocean color remote sensing, underwater photovoltaic power, etc. It is a key apparent optical property (AOP) and is sensitive to the volume scattering function ß(ψ, z, λ). Here, using three machine learning algorithms (MLAs) (categorical boosting (CatBoost), light gradient boosting machine (LightGBM), and random forest (RF)), we developed a new approach for estimating the vertical distribution of Kd(z, 650), KLu(z, 650), and Ku(z, 650) and applied it to the South China Sea (SCS). In this approach, based on in situ ß(ψ, z, 650), the absorption coefficient a(z, 650), the profile depths z, and Kd(z, 650), KLu(z, 650), and Ku(z, 650) calculated by Hydrolight 6.0 (HL6.0), three machine learning models (MLMs) without or with boundary conditions for estimating Kd(z, 650), KLu(z, 650), and Ku(z, 650) were established, evaluated, compared, and applied. It was found that (1) CatBoost models have superior performance with R2 ≥ 0.92, RMSE≤ 0.021 m-1, and MAPE≤ 4.3% and most significantly agree with HL6.0 simulations; (2) there is a more satisfactory consistency between HL6.0 simulations and MLMs estimations while incorporating the boundary conditions; (3) the estimations of Kd(z, 650), KLu(z, 650), and Ku(z, 650) derived from CatBoost models with and without boundary conditions have a good agreement with R2 ≥0.992, RMSE ≤0.007 m-1, and MAPE≤0.8%, respectively; (4) there is an overall decreasing trend with increasing depth and increasing offshore distance of Kd(z, 650), KLu(z, 650), and Ku(z, 650) in the SCS. The MLMs for estimating K(z, λ) could provide more accurate information for the study of underwater light field distribution, water quality assessment and the validation of remote sensing data products.

4.
Mol Med Rep ; 17(5): 6927, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29436677

RESUMO

An interested reader drew to the attention of the Editorial Board of Molecular Medicine Reports that certain data in the above paper had already been published in a previous study featuring several of the same authors [Zhang XQ, Huang XF, Hu XB, Zhan YH, An QX, Yang SM, Xia AJ, Yi J, Chen R, Mu SJ and Wu DC: "Apogossypolone, a novel inhibitor of antiapoptotic Bcl-2 family proteins, induces autophagy of PC-3 and LNCaP prostate cancer cells in vitro". Asian J Androl 12: 697-708, 2010]. Specifically, Figs. 2A and 5C were originally featured, either in their entirety or in part, as Figs 6C and 2G, respectively, in the Asian J Androl paper. Following an internal investigation, the Editorial Board was able to confirm that these data were published previously in the Asian J Androl paper, and therefore it has been decided that the above-mentioned paper should be retracted on account of the incidences of data sharing. The authors have agreed to this decision, and we apologize to the readership of the Journal for any inconvenience caused. [the original article was published in Molecular Medicine Reports 10: 1184-1194, 2014; DOI: 10.3892/mmr.2014.2379].

5.
Transfus Med Rev ; 31(2): 107-112, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28063764

RESUMO

Patients with cirrhosis used to be associated with frequent use of blood components because of their complex disorder of hemostasis and bleeding complications. Recent findings have indicated that patients with cirrhosis have a state of "rebalanced" or even procoagulant hemostasis and have questioned the prophylactic use of plasma. To evaluate the current status of plasma use in patients with cirrhosis, we conducted a retrospective survey in 11 tertiary-care hospitals in China from September 1 to October 31, 2013. All patients admitted with cirrhosis during the study period were included in the study. The survey collected information including patients' diagnostic and demographic data, clinical course including bleeding complications and invasive procedures, laboratory results, and plasma transfusion data. Among 1595 patients with cirrhosis admitted to the 11 hospitals, 236 (14.8%) patients received 1 or more plasma transfusions during the study period. The number of plasma transfusions is defined as the number of transfusion orders. A total of 1037 plasma transfusions were administered to these patients, with a mean of 4.4 transfusions per transfused patient, ranging from 1 to 22 transfusions per transfused patient. Most plasma transfusions (760/1037; 73.3%) were given to patients without bleeding, for treatment of coagulopathy either without planned invasive procedures (70.4%) or before invasive procedures (2.9%). The median dose of plasma transfusion was 3.8 mL/kg. The rate of plasma transfusion of participating hospitals varied from 5.3% to 31.8%. It is encouraging to see that in one teaching hospital, 85.7% plasma transfusions were given to patients with bleeding indication, showing a promising sign in appropriate transfusion. Prophylaxis or empirical plasma transfusion is still a common problem in managing patients with liver cirrhosis. Wide variations are found in plasma transfusion practice among hospitals. Effective measures to control and reduce empirical correction of abnormal coagulation tests through transfusing plasma should be strengthened urgently.


Assuntos
Transtornos da Coagulação Sanguínea/terapia , Transfusão de Componentes Sanguíneos , Cirrose Hepática/terapia , Adulto , Transtornos da Coagulação Sanguínea/complicações , Transtornos da Coagulação Sanguínea/epidemiologia , Transfusão de Componentes Sanguíneos/estatística & dados numéricos , China/epidemiologia , Comorbidade , Feminino , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Centros de Atenção Terciária/estatística & dados numéricos
6.
Dig Liver Dis ; 48(12): 1478-1484, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27665260

RESUMO

BACKGROUND: Cirrhosis is a complex acquired disorder of hemostasis and patients frequently receive blood transfusions. But there is very limited data on patterns of blood use at a patient level. AIMS: To characterize blood use in cirrhotic patients in China and compare with recommendations to help identify areas where quality improvement strategies can be targeted. We also compared findings to a similar study undertaken in UK. METHODS: A cross-sectional study was conducted in 11 hospitals over a 2-month period. Data were collected prospectively on each hospitalized cirrhotic patient to day 28. RESULTS: 1595 cirrhotic patients were included and 20.6% were transfused. 48.2% of transfused patients received transfusion for bleeding, most commonly gastrointestinal bleeding (65.8%). The remaining 51.8% were transfused for non-bleeding indications. 32.5% of patients transfused for gastrointestinal bleeding with red blood cells had a pre-transfusion haemoglobin >7g/dL. 89.1% of patients transfused frozen plasma for non-bleeding indications received them in the absence of a planned procedure. The patterns of blood transfusion in cirrhosis were different between China and UK. Of note, empirical prophylactic use of frozen plasma was more common in the Chinese study (89%) than in the UK (24%). CONCLUSION: Education and research should be implemented to improve patient blood management, especially in prophylactic frozen plasma use area.


Assuntos
Transfusão de Componentes Sanguíneos/estatística & dados numéricos , Hemorragia Gastrointestinal/terapia , Cirrose Hepática/complicações , Adulto , Idoso , China , Estudos Transversais , Feminino , Hemoglobinas/análise , Humanos , Tempo de Internação , Cirrose Hepática/etiologia , Masculino , Pessoa de Meia-Idade , Plasma , Estudos Prospectivos , Melhoria de Qualidade , Reino Unido
7.
Int Immunopharmacol ; 26(1): 50-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25773667

RESUMO

Mesenchymal stromal cells (MSCs) have therapeutic potential for the prevention and treatment of graft-versus-host disease (GVHD). However, MSCs comprise several subpopulations, which have not been individually assessed for their role in GVHD suppression. In this study, we assessed the immunosuppressive effect of bone-related Sca1(+) MSCs on acute GVHD in a MHC-mismatched mouse model of allogeneic hematopoietic stem cell transplantation (HCT). Our results showed that Sca1(+) MSCs decreased the severity of acute GVHD (aGVHD) and prolonged the survival period of allogeneic HCT recipients. This effect was exerted through lowered T lymphocyte infiltration in target organs and by inhibition of CD80/86 expression on host dendritic cells. Furthermore, the expression of cytotoxic T-lymphocyte antigen-4 (CTLA-4), a negative regulator of T cells, was elevated in the recipient splenocytes. In conclusion, bone-related Sca1(+) MSCs subpopulation suppressed GVHD and could be a novel treatment for acute GVHD.


Assuntos
Ataxina-1/imunologia , Transplante de Medula Óssea , Doença Enxerto-Hospedeiro/prevenção & controle , Células-Tronco Mesenquimais/imunologia , Animais , Transplante de Células , Feminino , Citometria de Fluxo , Doença Enxerto-Hospedeiro/imunologia , Infusões Intravenosas , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase em Tempo Real , Baço/citologia , Baço/imunologia , Análise de Sobrevida
8.
Mol Med Rep ; 10(3): 1184-94, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25060748

RESUMO

The aim of the present study was to investigate the anti­tumor effect of apogossypolone (ApoG2) on human LNCaP cells in vitro and in vivo. Cell viability was evaluated using an MTT assay. Cell autophagy and apoptosis were detected by flow cytometry and using a terminal deoxynucleotidyl transferase dUTP nick end labeling assay, respectively. Morphological autophagy alterations were observed by transmission electron microscopy. The formation of acidic vesicular organelles was assessed by acridine orange staining and fluorescence microscopy. Quantitative polymerase chain reaction (qPCR) was conducted to detect the expression levels of apoptosis­associated protein B­cell lymphoma 2 (Bcl­2) and Bak. The models of transplantation tumors in nude mice were established via subcutaneous injection of LNCaP cells. Growth of LNCaP cells was inhibited by ApoG2 treatment. Flow cytometry demonstrated that ApoG2 induced apoptosis in LNCaP cells. The Bcl­2 expression was decreased while Bak expression was increased. In addition, activation of cysteine aspartate protease (caspase)­3 and ­8 was observed and 3­methyladenine (3­MA) enhanced apoptosis of LNCaP cells. Furthermore, nude mice treated with ApoG2 demonstrated a significant decrease in tumor volume and a significant increase in cell viability. Immunohistochemical analysis of tumor tissues demonstrated that ApoG2 enhanced caspase­3, ­8, LC­3B and beclin­1 expression and reduced the expression of Bcl­2. ApoG2 was able to effectively suppress the growth of LNCaP cells through the induction of autophagy and apoptosis.


Assuntos
Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Gossipol/análogos & derivados , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Autofagia/efeitos dos fármacos , Proteína Beclina-1 , Caspase 3/genética , Caspase 3/metabolismo , Caspase 8/genética , Caspase 8/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Gossipol/farmacologia , Humanos , Marcação In Situ das Extremidades Cortadas , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Microscopia Eletrônica de Transmissão , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína Killer-Antagonista Homóloga a bcl-2/genética , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo
9.
Viruses ; 6(7): 2723-34, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25029493

RESUMO

Cell-free DNA (cf-DNA) in blood represents a promising DNA damage response triggered by virus infection or trauma, tumor, etc. Hantavirus primarily causes two diseases: haemorrhagic fever with renal syndrome (HFRS) and Hantavirus cardiopulmonary syndrome (HCPS), depending on different Hantavirus species. The aim of this study was to evaluate plasma cf-DNA levels in acute phase of HFRS, and to correlate plasma cf-DNA with disease severity and plasma Hanttan virus (HTNV) load. We observed the appearance of cf-DNA in 166 plasma samples from 76 HFRS patients: the plasma cf-DNA levels peaked at the hypotensive stage of HFRS, and then decreased gradually. Until the diuretic stage, there was no significant difference in plasma cf-DNA level between patients and the healthy control. Exclusively in the febrile/hypotensive stage, the plasma cf-DNA levels of severe/critical patients were higher than those of the mild/moderate group. Moreover, the plasma cf-DNA value in the early stage of HFRS was correlated with HTNV load and disease severity. In most of the patients, plasma cf-DNA displayed a low-molecular weight appearance, corresponding to the size of apoptotic DNA. In conclusion, the plasma cf-DNA levels were dynamically elevated during HFRS, and correlated with disease severity, which suggests that plasma cf-DNA may be a potential biomarker for the pathogenesis and prognosis of HFRS.


Assuntos
DNA Viral/sangue , Vírus Hantaan/fisiologia , Febre Hemorrágica com Síndrome Renal/patologia , Febre Hemorrágica com Síndrome Renal/virologia , Carga Viral , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Criança , Progressão da Doença , Feminino , Vírus Hantaan/patogenicidade , Febre Hemorrágica com Síndrome Renal/sangue , Febre Hemorrágica com Síndrome Renal/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Desnaturação de Ácido Nucleico , Índice de Gravidade de Doença
10.
Biomed Rep ; 2(1): 39-40, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24649066

RESUMO

The aim of this study was to investigate the application of plasma exchange in small intestinal transplantation between ABO blood type-incompatible patients. A small intestinal transplantation case between ABO-incompatible individuals is hereby presented and analyzed. The main treatment included plasma exchange, splenectomy and immunosuppression. The patient undergoing small intestinal transplantation exhibited stable vital signs. A mild acute rejection reaction developed ~2 weeks after the surgery, which the patient successfully overcame. The subsequent colonoscopy and pathological examination revealed no signs of acute rejection. In conclusion, plasma exchange in combination with anti-immune rejection therapy proved to be an effective scheme for the management of small intestinal transplantation between ABO-incompatible patients.

11.
Int J Infect Dis ; 19: 98-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24291114

RESUMO

This study was conducted to examine the prevalence of syphilis among blood donors in the Xi'an region of China. All blood donors were unremunerated volunteers recruited from 2006 to 2010. Anti-Treponema pallidum and anti-HIV serology responses were determined using ELISA kits. Among 159 902 voluntary blood donors tested, a total of 575 syphilis (0.36%) and 55 HIV (0.03%) infections were identified. While an increasing trend was shown for the prevalence of both syphilis and HIV over the 5-year period, there was no statistical correlation between the two infections. Our results indicate that syphilis and HIV infections are increasing risk factors for the spread of blood-borne infections. Further investigations and improvements in blood collection and testing procedures are needed to help ensure the safety of donated blood in China.


Assuntos
Anticorpos Antibacterianos/sangue , Infecções por HIV/epidemiologia , HIV-1/imunologia , HIV-2/imunologia , Sífilis/epidemiologia , Treponema pallidum/imunologia , Adolescente , Adulto , Doadores de Sangue , Transfusão de Sangue , China/epidemiologia , Feminino , Anticorpos Anti-HIV/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Estudos Soroepidemiológicos , Adulto Jovem
12.
Asian Pac J Cancer Prev ; 14(3): 1791-5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23679275

RESUMO

AIMS AND BACKGROUND: Prostate cancer is one of the most common malignant tumors in the male reproductive system, which causes the second most cancer deaths of males, and control of angiogenesis in prostate lesions is of obvious importance. This study assessed the effect of apogossypolone (ApoG2) on proliferation and apoptosis of human umbilical vein endothelial cells (HUVECs). SUBJECTS AND METHODS: HUVECs were treated with different concentrations of ApoG2. The survival rate of HUVECs were determined by MTT assay. Utrastructural changes of HUVECs were assessed with transmission electron microscopy. Apoptosis in HUVECs was analyzed by flow cytometry and cell migration by Boyden chamber assay. Matrigel assays were used to quantify the development of tube-like networks. RESULTS: ApoG2 significantly inhibited HUVEC growth even at 24 h (P<0.05). The inhibitory effect of ApoG2 is more obvious as the concentration and the culture time increased (P<0.05). These results indicate that ApoG2 inhibits the proliferation of HUVECs in a time- and concentration-dependent manner with increase of the apoptosis rate. Besides, ApoG2 reduced the formation of total pseudotubule length and network branches of HUVECs. CONCLUSIONS: The results suggest that ApoG2 inhibits angiogenesis of HUVECs by growth inhibition and apoptosis induction.


Assuntos
Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Gossipol/análogos & derivados , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Células Cultivadas , Colágeno/metabolismo , Combinação de Medicamentos , Citometria de Fluxo , Gossipol/farmacologia , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Laminina/metabolismo , Proteoglicanas/metabolismo
13.
Transfusion ; 53(11): 2722-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23550657

RESUMO

BACKGROUND: Comprehensive and accurate detection of human platelet antigens (HPAs) plays a significant role in diagnosis and prevention of the platelet (PLT) alloimmune syndromes and ensuring clinical safety of patients undergoing PLT transfusion. The majority of the available methods are incapable of performing high-throughput simultaneous detection of HPA-1 to -16, and the accuracy of many methods needs to be further enhanced. STUDY DESIGN AND METHODS: We have developed a new HPA-genotyping method for simultaneous detection of HPA-1 to -16 based on suspension array technology. A total of 216 samples from Chinese Han donors in Xi'an were genotyped using the developed method, and all the samples again were genotyped using polymerase chain reaction (PCR) sequence-based typing (PCR-SBT), which is considered the gold standard. RESULTS: All 216 samples were successfully genotyped for HPA-1 to -16 using both our method and PCR-SBT. Results showed that the genotype and allele frequencies obtained using our method were fully consistent with those obtained using PCR-SBT. CONCLUSION: Our method provides accurate, high-throughput, and simultaneous genotyping of HPA-1 to -16 and will serve as the foundation for large-scale clinical genotyping of HPAs and for the establishment of an HPA-typed PLT donor registry.


Assuntos
Antígenos de Plaquetas Humanas/genética , Sequência de Bases , Genótipo , Ensaios de Triagem em Larga Escala , Humanos , Dados de Sequência Molecular , Transfusão de Plaquetas , Reação em Cadeia da Polimerase , Suspensões
14.
Transfus Apher Sci ; 49(3): 474-81, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23548440

RESUMO

Transfusion-related acute lung injury (TRALI) is a serious complication associated with blood transfusion and can cause transfusion associated fatalities. Both antibody dependent and non-dependent mechanisms are involved in TRALI, as proposed over the past years. Nonetheless, many details of the immune cells involved in TRALI, particularly the Mac1(+)/Gr1(+) cells from donors, are not fully understood yet. Here we used an in vitro transwell system and a mouse model to study the role of donor leukocytes, present in the donor material, in the occurrence of TRALI reactions. We found that there is a number of immature myeloid cells with Mac1(+)/Gr1(+) phenotype present in the red blood cell (RBC) products, when prepared by regular methods. We found that murine Mac1(+)/Gr1(+) cells from stored RBC products display an elevated MHC I and CD40 expression, as well as an enhanced tumor necrosis factor alpha(TNF-α), interlukin-6(IL-6) and macrophage inflammatory protein 2 (MIP-2) secretion. When tested in a transwell endothelial migration assay, Mac1(+)/Gr1(+) cells showed a significant capability to cross the endothelial barrier. In vivo investigation demonstrated that compared to the purified RBC transfusion, more murine Mac1(+)/Gr1(+) cells from the regular method produced RBC sequestered in the lung, which associated to shorter survival. Taken together, these data suggest that donor derived Mac1(+)/Gr1(+) cells can play a significant role in TRALI reactions, and that reduction of Mac1(+)/Gr1(+) cell number from RBC products is necessary to control the severity of TRALI reactions in clinic.


Assuntos
Lesão Pulmonar Aguda/etiologia , Células Mieloides/imunologia , Reação Transfusional , Lesão Pulmonar Aguda/imunologia , Adolescente , Adulto , Animais , Anticorpos/imunologia , Doadores de Sangue , Antígeno CD11b/biossíntese , Antígeno CD11b/imunologia , Citocinas/imunologia , Feminino , Citometria de Fluxo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Modelos Animais , Receptores de Quimiocinas/biossíntese , Receptores de Quimiocinas/imunologia , Adulto Jovem
15.
Biomed Rep ; 1(2): 243-246, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24648928

RESUMO

The aim of this study was to examine the manner in which varying proportions of serum and red blood cells (RBC) in massive blood transfusion affect the survival rates of patients with severe blood loss. Massive transfusion (MT) was determined as receiving ≥10 units of red blood cells in 24 h. The electronic medical records and blood transfusion information for the period January, 2002 to December, 2011 of patients with MT were examined. Moreover, we calculated the ratio of blood components and examined their correlation with survival. In total, 1,658 patients underwent MT during the period 2002-2011, with an overall of 28,030 units RBC, accounting for 2.8% of the total blood transfusion. In conclusion, fixing blood-component ratios has the potential to help improve survival rate in MT.

16.
Arch Biochem Biophys ; 507(2): 343-9, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21211509

RESUMO

Increasing evidence has demonstrated that EGCG possesses prooxidant potential in biological systems, including modifying proteins, breaking DNA strands and inducing the generation of reactive oxygen species. In the present study, the prooxidant effect of EGCG on erythrocyte membranes was investigated. SDS-PAGE and NBT-staining assay were utilized to detect the catechol-protein adducts that generated upon treating the membranes with EGCG. The results indicated that EGCG was able to bind covalently to sulfhydryl groups of membrane proteins, leading to the formation of protein aggregates with intermolecular cross-linking. We suggested that the catechol-quinone originated from the oxidation of EGCG acted as a cross-linker on which peptide chains were combined through thiol-S-alkylation at the C2- and C6-sites of the gallyl ring. EGC showed similar effects as EGCG on the ghost membranes, whereas ECG and EC did not, suggesting that a structure with a gallyl moiety is a prerequisite for a catechin to induce the aggregation of membrane proteins and to deplete membrane sulfhydryls. EDTA and ascorbic acid inhibited the EGCG-induced aggregation of membrane proteins by blocking the formation of catechol-quinone. The information of the present study may provide a fresh insight into the prooxidant effect and cytotoxicity of tea catechins.


Assuntos
Catequina/análogos & derivados , Reagentes de Ligações Cruzadas/farmacologia , Flavonoides/farmacologia , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Fenóis/farmacologia , Chá/química , Ácido Ascórbico/farmacologia , Benzoquinonas/química , Benzoquinonas/farmacologia , Catequina/farmacologia , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Ácido Edético/farmacologia , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Humanos , Peso Molecular , Polifenóis , Multimerização Proteica/efeitos dos fármacos , Estrutura Quaternária de Proteína , Espécies Reativas de Oxigênio/farmacologia , Compostos de Sulfidrila/metabolismo
17.
Virol J ; 7: 186, 2010 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-20698949

RESUMO

HCV is prevailed in the world as well as in China. Blood transfusion is one of the most common transmission pathways of this pathogen. Although data of HCV infection character were reported during the past years, anti-HCV reactive profile of China donors was not fully clear yet. Furthermore, infection progress was found related to the HCV genotype. Different genotype led to different efficacy when interferon was introduced into HCV therapy. Here we provided character data of HCV infection in China blood donors from the year of 2000 to 2009. The infection rate in local donors was lower than general population and descended from 0.80% to 0.40% or so in recent years. About 83% HCV strains were categorized into genotypes 1b and 2a. But 1b subtype cases climbed and 2a subtype cases decreased. The current study threw more light on HCV infection of blood donors in China, at least in the Northern region.


Assuntos
Doadores de Sangue , Hepacivirus/isolamento & purificação , Anticorpos Anti-Hepatite C/sangue , Hepatite C/epidemiologia , Hepatite C/virologia , China/epidemiologia , Ensaio de Imunoadsorção Enzimática , Genótipo , Hepacivirus/genética , Humanos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estudos Soroepidemiológicos
18.
Asian J Androl ; 12(5): 697-708, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20657602

RESUMO

Limited treatment options are available for aggressive prostate cancer. Gossypol has been reported to have a potent anticancer activity in many types of cancer. It can increase the sensitivity of cancer cells to alkylating agents, diminish multidrug resistance and decrease metastasis. Whether or not it can induce autophagy in cancer cells has not yet been determined. Here we investigated the antiproliferative activity of apogossypolone (ApoG2) and (-)-gossypol on the human prostate cancer cell line PC3 and LNCaP in vitro. Exposure of PC-3 and LNCaP cells to ApoG2 resulted in several specific features characteristic of autophagy, including the appearance of membranous vacuoles in the cytoplasm and formation of acidic vesicular organelles. Expression of autophagy-associated LC3-II and beclin-1 increased in both cell lines after treatment. Inhibition of autophagy with 3-methyladenine promoted apoptosis of both cell types. Taken together, these data demonstrated that induction of autophagy could represent a defense mechanism against apoptosis in human prostate cancer cells.


Assuntos
Antineoplásicos/farmacologia , Linhagem Celular Tumoral/efeitos dos fármacos , Gossipol/análogos & derivados , Neoplasias da Próstata/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Adenina/análogos & derivados , Adenina/farmacologia , Adenina/uso terapêutico , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral/ultraestrutura , Ensaios de Seleção de Medicamentos Antitumorais , Gossipol/farmacologia , Gossipol/uso terapêutico , Inibidores do Crescimento/farmacologia , Inibidores do Crescimento/uso terapêutico , Humanos , Masculino , Neoplasias da Próstata/patologia
19.
Arch Virol ; 155(7): 1097-105, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20473626

RESUMO

Because no vaccine or effective therapy is available, thousands of people with HCV have died in recent years. Cytotoxic T lymphocytes (CTLs) play a critical role in the host cellular immune response against HCV. CTL epitopes in HCV core protein have been identified and used in vaccine development. T helper epitopes could promote cytokine secretion and antibody production to fight HCV. Tetanus toxin, an immunogen with many T helper epitopes, was once used in HBV therapeutic vaccine design. Here, eukaryotic and prokaryotic expression vectors were constructed to express truncated fragments of tetanus toxin and core genes of HCV. HLAA2.1 transgenic mice were inoculated with a recombinant plasmid vehicle with these two heterogenic gene fragments, and this augmented the titres of antibody against HCV. Antigen-specific lymphocyte proliferation, Th1 and Th2 cytokine levels and the number of lysed cells were markedly increased in the combined immunization group compared to controls. These findings provide new insights into a potential role for T helper epitopes from tetanus toxin combined with protein from the HCV core gene, which has numerous CTL epitopes. This design strategy may aid in the development of new vaccines against HCV.


Assuntos
Hepacivirus/imunologia , Hepatite C/prevenção & controle , Toxina Tetânica/imunologia , Vacinas Sintéticas/imunologia , Proteínas do Core Viral/imunologia , Vacinas Virais/imunologia , Animais , Proliferação de Células , Camundongos , Camundongos Transgênicos , Proteínas Recombinantes , Linfócitos T Citotóxicos/citologia , Linfócitos T Citotóxicos/fisiologia , Toxina Tetânica/química , Proteínas do Core Viral/química
20.
Asian J Androl ; 12(3): 390-9, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20081872

RESUMO

We investigated the antiproliferative activity of (-)-gossypol on the human prostate cancer cell line PC3 in vitro and in vivo to elucidate its potential molecular mechanisms. Cell growth and viability were evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and cell apoptosis was detected by flow cytometry, terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) and electron microscopy. Expression of proliferating cell nuclear antigen (PCNA), Bcl-2, CD31, caspase-3 and caspase-8 in tumour tissue was determined by immunohistochemistry. The drug concentration that yielded 50% cell inhibition (IC(50) value) was 4.74 microg mL(-1). In the PC-3 tumour xenograft study, (-)-gossypol (> 5 mg kg(-1)) given once a day for 7 days significantly inhibited tumour growth in a dose-dependent manner. Immunohistochemical analysis revealed that (-)-gossypol enhanced caspase-3 and caspase-8 expression and decreased the expression of PCNA, Bcl-2 and CD31 in tumour tissues. It suggested that cell apoptosis and inhibition of angiogenesis might contribute to the anticancer action of (-)-gossypol.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/farmacologia , Anticoncepcionais Masculinos/farmacologia , Gossipol/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Adenocarcinoma/irrigação sanguínea , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Animais , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Marcação In Situ das Extremidades Cortadas , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Microvasos/efeitos dos fármacos , Microvilosidades/efeitos dos fármacos , Microvilosidades/ultraestrutura , Neovascularização Patológica/tratamento farmacológico , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Neoplasias da Próstata/irrigação sanguínea , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-bcl-2 , Sais de Tetrazólio , Tiazóis , Ensaios Antitumorais Modelo de Xenoenxerto
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