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1.
Viruses ; 16(6)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38932262

RESUMO

Hepatitis A virus (HAV), a member of the genus Hepatovirus (Picornaviridae HepV), remains a significant viral pathogen, frequently causing enterically transmitted hepatitis worldwide. In this study, we conducted an epidemiological survey of HepVs carried by small terrestrial mammals in the wild in Yunnan Province, China. Utilizing HepV-specific broad-spectrum RT-PCR, next-generation sequencing (NGS), and QNome nanopore sequencing (QNS) techniques, we identified and characterized two novel HepVs provisionally named EpMa-HAV and EpLe-HAV, discovered in the long-tailed mountain shrew (Episoriculus macrurus) and long-tailed brown-toothed shrew (Episoriculus leucops), respectively. Our sequence and phylogenetic analyses of EpMa-HAV and EpLe-HAV indicated that they belong to the species Hepatovirus I (HepV-I) clade II, also known as the Chinese shrew HepV clade. Notably, the codon usage bias pattern of novel shrew HepVs is consistent with that of previously identified Chinese shrew HepV. Furthermore, our structural analysis demonstrated that shrew HepVs differ from other mammalian HepVs in RNA secondary structure and exhibit variances in key protein sites. Overall, the discovery of two novel HepVs in shrews expands the host range of HepV and underscores the existence of genetically diverse animal homologs of human HAV within the genus HepV.


Assuntos
Genoma Viral , Filogenia , Musaranhos , Animais , Musaranhos/virologia , China/epidemiologia , RNA Viral/genética , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Infecções por Picornaviridae/veterinária , Infecções por Picornaviridae/virologia , Infecções por Picornaviridae/epidemiologia
2.
Zhongguo Dang Dai Er Ke Za Zhi ; 15(7): 550-4, 2013 Jul.
Artigo em Zh | MEDLINE | ID: mdl-23866277

RESUMO

OBJECTIVE: To investigate the epidemiological characteristics of intolerance to 14 foods in children and the relationship between food intolerance and disease of various systems. METHODS: Serum samples of 2434 children with diseases were collected for food intolerance testing between January 2009 and October 2012. Allergen-specific IgG antibodies to 14 foods were detected using enzyme-linked immunosorbent assay. The children's intolerance to different foods and its relationship with age, sex and disease of various systems were analyzed. RESULTS: Among these children, positive rates of intolerance to milk and eggs were as high as 74.16% and 66.47% respectively, while positive rates of intolerance to chicken and pork were relatively low (0.29% and 0.21% respectively). The overall positive rates of food intolerance were 12.579% and 12.470% in males and females respectively. For infants, the highest intolerance rate was to milk; for preschool and school-age children, the highest intolerance rates were to milk and eggs respectively; for children in adolescence, the highest intolerance rate was to eggs. Among children with food intolerance involving single system, those with developmental abnormality or immune system disease had the highest overall positive rate of food intolerance. Children with double-system diseases had an overall positive rate of food intolerance as high as 13.393%. Among the children involving various systems, the positive rate of intolerance to milk and eggs were higher than other food. CONCLUSIONS: Factors influencing food intolerance in children include food categories and age. There may be a relationship between food intolerance and disease of various systems, and this is significant to the growth and development of children.


Assuntos
Hipersensibilidade Alimentar/epidemiologia , Criança , Pré-Escolar , China/epidemiologia , Hipersensibilidade a Ovo/epidemiologia , Estudos Epidemiológicos , Feminino , Humanos , Lactente , Masculino , Hipersensibilidade a Leite/epidemiologia
3.
Zhongguo Dang Dai Er Ke Za Zhi ; 13(8): 674-6, 2011 Aug.
Artigo em Zh | MEDLINE | ID: mdl-21849122

RESUMO

OBJECTIVE: To study the molecular mechanism of apoptosis of leukemic cells (K562 cells) induced by iron chelating agent deferoxamine (DFO). METHODS: The exponentially growing K562 cells were used (1×10(6)/mL) in this study. The K562 cells were treated with different concentrations of DFO (10, 50 and 100 mmol/L), DFO+FeCl3 (10 µmol/L each) or normal saline (blank control). The cellular labile iron pool was measured with a fluorimetric assay using the metalsensitive probe calcein-AM. The viable count and cell viability were determined by typanblue assay. Cell apoptosis was determined by morphological study and flow cytometry assay. Caspase-3 activity in K562 cells was detected by colorimetry. RESULTS: After DFO treatment, the cellular labile iron pool and the viability of K562 cells were reduced and the cell apoptosis increased in a time- and dose-dependent manner compared with the blank control group. The apoptosis rate of K562 cells in the DFO+FeCl3 treatment group was not significantly different from that in the blank control group. The caspase-3 activity in K562 cells increased significantly 24 hrs after 50 and 100 µmmol DFO treatment when compared with the blank control group (P<0.01). There was a negative correlation between cellular labile iron pool and caspase-3 activity of K562 cells (r=-0.894, P<0.05). CONCLUSIONS: DFO induces apoptosis of leukemic cells possibly through decreasing cellular labile iron pool and increasing caspase-3 activity of the cells.


Assuntos
Apoptose/efeitos dos fármacos , Desferroxamina/farmacologia , Quelantes de Ferro/farmacologia , Caspase 3/metabolismo , Citometria de Fluxo , Humanos , Células K562
4.
World J Gastroenterol ; 26(30): 4501-4522, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32874061

RESUMO

BACKGROUND: No guideline recommends antiviral therapy for hepatitis B e antigen (HBeAg)-positive chronic hepatitis B patients with persistently normal alanine aminotransferase levels and a high hepatitis B virus (HBV) DNA viral load. AIM: To evaluate the feasibility and safety of a Chinese herbal formula as a therapeutic option for chronic HBV infection. METHODS: In total, 395 patients (30-65 years old) with confirmed HBeAg-positive chronic hepatitis B infection and persistently normal alanine aminotransferase were randomized to receive either Chinese herbal formula or placebo for 96 wk. Endpoints to evaluate therapeutic efficacy included: (1) HBV DNA levels decreased to less than 4 log10 IU/mL at weeks 48 and 96; and (2) HBeAg clearance and seroconversion rates at weeks 48 and 96. RESULTS: HBV DNA levels ≤ 4 log10 IU/mL were 10.05% at week 48 and 18.59% at week 96 in the treatment group. The HBeAg clearance and conversion rates were 8.54% and 8.04% at week 48 and 16.08% and 14.57% at week 96, respectively. However, HBV DNA levels ≤ 4 log10 IU/mL were 2.55% and 2.55% at weeks 48 and 96, respectively, and the HBeAg clearance rates were 3.06% and 5.61% at weeks 48 and 96, respectively, in the control group. The quantitative hepatitis B surface antigen and HBeAg levels at baseline and changes during the treatment period as well as the alanine aminotransferase elevation at weeks 12 and 24 were strong predictors of HBeAg clearance. CONCLUSION: High rates of HBV DNA reduction, HBeAg clearance and seroconversion could be achieved with Chinese herbal formula treatments, and the treatments were relatively safe for HBeAg-positive chronic hepatitis B-infected patients with persistently normal alanine aminotransferase. The ability of the compound to modulate host immune function probably contributed to this effect.


Assuntos
Antígenos E da Hepatite B , Hepatite B Crônica , Adulto , Idoso , Antivirais/efeitos adversos , China , DNA Viral/uso terapêutico , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B/genética , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/tratamento farmacológico , Humanos , Pessoa de Meia-Idade , Resultado do Tratamento
5.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 40(1): 133-7, 2009 Jan.
Artigo em Zh | MEDLINE | ID: mdl-19292063

RESUMO

OBJECTIVE: To investigate the anti-neoplastic effects of Valproic acid (VPA) on leukemic cells, especially drug-resistant lines, and to investigate whether modulation of GSH-redox status is involved in VPA-induced apoptosis. METHODS: After the treatment of VPA at various concentrations for indicated times, cellular proliferation of the Jurkat, CEM, HL-60, K562, K562/AO2 cells were evaluated via MTT assay; and the activities of Caspase-3, Caspase-8 and Caspase-9 were quantitatively analyzed by colorimetric assay. The morphological change and cell cycle distribution were also examined on Jurkat (Dexamethasone-resistant) and K562/AO2 (Doxorubicin-resistant) cell lines. The levels of intracellular glutathione/glutathione disulfide (GSH/GSSG) and the activities of the typical antioxidant enzymes, i.e., glutathione reductase (GSH-Rd) and glutathione peroxidase (GSH-Px), were measured on cell lysates of Jurkat and K562/AO2 cell lines prior to and after VPA treatment. Apoptosis rates of Jurkat and K562/AO2 cells treated with VPA along or in combination with N-acety-l-cysteine (NAC), catalase (CAT) or DL-buthionine-(S,R)-sulfoximine (BSO) were determined by Annexin V/propidium iodide (PI) staining with flow cytometry analysis. RESULTS: At concentrations comparable with that achieved at clinical settings, VPA inhibited cell proliferation, activated Caspase-3, 8, and 9, and induced cell cycle arrest in Jurkat and K562/AO2. A rapid decrease in GSH-Rd and GSH-Px activities and GSH content in Jurkat and K562/AO2 were detected after VPA treatment. Co-administration of NAC or CAT attenuated VPA-induced apoptosis. CONCLUSION: VPA inhibit cell proliferation, induce cell cycle arrest and apoptosis in drug-resistant leukemic cells. Apoptosis correlates with down-regulation of intracellular GSH and disruption of intracellular GSH-redox balance, possibly through inhibition of glutathione reductase and glutathione peroxidase.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Glutationa/metabolismo , Ácido Valproico/farmacologia , Dexametasona/farmacologia , Doxorrubicina/farmacologia , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Células HL-60 , Humanos , Células Jurkat , Células K562
6.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 24(5): 560-3, 2007 Oct.
Artigo em Zh | MEDLINE | ID: mdl-17922427

RESUMO

OBJECTIVE: To determine the incidence of TEL-AML1 fusion gene in childhood acute lymphoblastic leukemia (ALL) and to compare the clinical features between TEL-AML1 positive and negative patients. METHODS: Samples of bone marrow or peripheral blood were collected from 95 newly diagnosed ALL children and the TEL-AML1 fusion gene was detected using nested reverse transcription-polymerase chain reaction (RT-PCR). The ALL patients were stratified into TEL-AML1 positive and negative groups and the clinical features were compared. RESULTS: Among 95 patients, 20 (21.05%) were TEL-AML1 positive. The median age of TEL-AML1 positive patients was 5.9 years old and M/F ratio was 1.22:1. There were significant differences between TEL-AML1 positive and negative patients in hepatomegaly (2.75 cm vs. 4 cm below costal arch, P=0.006), splenomegaly (0 cm vs. 3 cm below costal arch, P < 0.001), initial white blood cell count (median 7.40 x 10(9)/L vs.18.70 x 10(9)/L, P=0.011), initial peripheral blood blast (median 2.45 x 10(9)/L vs.11.66 x 10(9)/L, P=0.013), hemoglobin level [(61.45 +/- 13.46) g/L vs. (75.89 +/- 23.11) g/L, P=0.003] and serum lactate dehydrogenase [(621.47 +/- 335.85) U/L vs.(1566.64 +/- 1720.45) U/L, P=0.020], while no differences were found between two groups in age, gender ratio, initial platelet count, percentage of blast in bone marrow, immunophenotypes and the expression of myeloid antigen CD13, CD33 and CD34. The prednisone sensitivity test showed that all 12 TEL-AML1 positive patients were good responders, while there were 11 prednisone poor responders among 40 negative patients (27.50%, P < 0.05). Bone marrow examination on day 15 showed no difference in the rate of complete remission between TEL-AML1 positive and negative patients. CONCLUSION: The incidence of TEL-AML1 fusion gene in cases of ALL is 21.05%. The load of leukemia cells in TEL-AML1 positive patients is significantly smaller than its counterparts, and the blast cells in TEL-AML1 positive patients are more sensitive to prednisone, indicating childhood ALL with TEL-AML1 fusion gene has a favorable prognosis.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/genética , Fusão Gênica , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Proteínas Proto-Oncogênicas c-ets/genética , Proteínas Repressoras/genética , Adolescente , Medula Óssea/patologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Fenótipo , Contagem de Plaquetas , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangue , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Prednisona/uso terapêutico , RNA/isolamento & purificação , Variante 6 da Proteína do Fator de Translocação ETS
7.
Int J Infect Dis ; 45: 36-42, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26899955

RESUMO

OBJECTIVES: In this study, we studied the N and H genes from wild type measles viruses (MeVs) isolated during the 2013-2014 outbreak. METHODS: Clinical samples were collected, and the genotyping, phylogenetic analysis were performed. RESULTS: The vaccination rate of the study population was 4%. Genotype H1a was the predominant genotype. Wild type viruses were classified into clusters A and B, C and may have different origins. N-450 sequences from wild type viruses were highly homologous with, and likely evolved from MeVs circulating in Tianjing and Henan in 2012. MVs/Shenyang.CHN/18.14/3 could have evolved from MeVs from Liaoning, Beijing, Hebei, Heilongjiang, Henan, Jilin, and Tianjin. Our data suggested that one or more of the same viruses circulated between Beijing, Shenyang, Hong Kong, Taiwan and Berlin. CONCLUSIONS: Important factors contributing to outbreaks could include weak vaccination coverage, poor vaccination strategies, and migration of adult workers between cities, countries, and from rural areas to urban areas.


Assuntos
Vírus do Sarampo/genética , Sarampo/virologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Feminino , Genótipo , Humanos , Masculino , Sarampo/epidemiologia , Sarampo/prevenção & controle , Vírus do Sarampo/classificação , Pessoa de Meia-Idade , Vacinação
8.
Chin J Integr Med ; 22(8): 573-80, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27220737

RESUMO

OBJECTIVE: To evaluate the clinical efficacy and safety of Yinchen Zhufu Decoction (, YCZFD) in the treatment of acute-on-chronic liver failure caused by hepatitis B virus (HBV-ACLF) with cold pattern in Chinese medicine (CM). METHODS: This is a multi-center randomized controlled trial of integrative treatment of CM and Western medicine (WM) for the management of HBV-ACLF patients. A total of 200 HBV-ACLF patients with cold pattern were equally randomly assigned to receive YCZFD and WM (integrative treatment) or WM conventional therapy alone respectively for 4 weeks. The primary end point was the mortality for HBV-ACLF patients. Secondary outcome measures included Model for End-Stage Liver disease (MELD) score, liver biochemical function, coagulation function and complications. Adverse events during treatment were reported. RESULTS: The mortality was decreased 14.28% in the integrative treatment group compared with WM group (χ(2) =6.156, P=0.013). The integrative treatment was found to signifificantly improve the MELD score (t=2.353, P=0.020). There were statistically signifificant differences in aspartate transaminase, total bilirubin, indirect bilirubin, direct bilirubin and prothrombin time between the two groups (P<0.05 or P<0.01). The complications of ascites (χ(2)=9.033, P=0.003) and spontaneous bacteria peritonitis (χ(2)=4.194, P=0.041) were improved signifificantly in the integrative treatment group. No serious adverse event was reported. CONCLUSIONS: The integrative treatment of CM and WM was effective and safe for HBV-ACLF patients with cold pattern in CM. The Chinese therapeutic principle "treating cold pattern with hot herbs" remains valuable to the clinical therapy. (Trial registration No. ChiCTR-TRC-10000766).


Assuntos
Insuficiência Hepática Crônica Agudizada/tratamento farmacológico , Insuficiência Hepática Crônica Agudizada/virologia , Medicamentos de Ervas Chinesas/uso terapêutico , Vírus da Hepatite B/fisiologia , Hepatite B/tratamento farmacológico , Insuficiência Hepática Crônica Agudizada/complicações , Insuficiência Hepática Crônica Agudizada/mortalidade , Adulto , Ascite/complicações , Demografia , Medicamentos de Ervas Chinesas/efeitos adversos , Medicamentos de Ervas Chinesas/farmacologia , Eletrólitos , Feminino , Hepatite B/complicações , Hepatite B/mortalidade , Hepatite B/fisiopatologia , Humanos , Medicina Integrativa , Fígado/efeitos dos fármacos , Fígado/patologia , Fígado/fisiopatologia , Fígado/virologia , Testes de Função Hepática , Masculino , Peritonite/complicações , Fatores de Tempo , Resultado do Tratamento
9.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 36(6): 804-7, 2005 Nov.
Artigo em Zh | MEDLINE | ID: mdl-16334558

RESUMO

OBJECTIVE: To investigate the effect of truncated PDGF-alpha receptor on proliferation expression of c-sis mRNA of pulmonary artery vascular smooth muscular cells(VSMC). METHODS: Tissue mass culture was done to get vascular smooth muscular cells of pulmonary artery. Different concentrations of truncated PDGF-alpha receptor and adenoviral recombined body (Ad5CMV-PalphaRtr, ACP) were added into the cultures. VSMC proliferation curves were obtained using MTT test. The expression of c-sis mRNA was detected by PCR. RESULTS: ACP at 5 ml/L and 10 ml/L concentrations restrained the proliferation of VSMC apparently with the peak of cell growth being attenuated or eliminated. The curve presented ascending tendency only after 7 days. Affected by 5 ml/L ACP, PDGF-BB exerted no significant accelerating effect on the proliferation of VSMC. The expression of c-sis mRNA was up-regulated under the effect of ACP. Affected by 5 ml/L ACP and PDGF-BB, the expression of c-sis mRNA was down-regulated. CONCLUSION: ACP at 5 ml/L and 10 ml/L concentration powerful inhibitor of cellular proliferation for pulmonary artery VSMC. It can increase c-sis mRNA expression significantly and the increase seems to be ACP dosage dependent.


Assuntos
Músculo Liso Vascular/metabolismo , Proteínas Proto-Oncogênicas c-sis/biossíntese , Artéria Pulmonar/citologia , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/fisiologia , Animais , Animais Recém-Nascidos , Proliferação de Células , Células Cultivadas , Feminino , Masculino , Músculo Liso Vascular/patologia , Proteínas Proto-Oncogênicas c-sis/genética , Artéria Pulmonar/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Suínos
10.
Chin J Integr Med ; 20(5): 394-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24174345

RESUMO

Treatment determination based on syndrome differentiation is the key of Chinese medicine. A feasible way of improving the clinical therapy effectiveness is needed to correctly differentiate the syndrome classifications based on the clinical manifestations. In this paper, a novel data mining method based on manifold ranking (MR) is proposed to explore the relation between syndromes and symptoms for viral hepatitis. Since MR could take the symptom data with expert differentiation and the symptom data without expert differentiation into the task of syndrome classification, the clinical information used for modeling the syndrome features is greatly enlarged so as to improve the precise of syndrome classification. In addition, the proposed method of syndrome classification could also avoid two disadvantages in previous methods: linear relation of the clinical data and mutually exclusive symptoms among different syndromes. And it could help exploit the latent relation between syndromes and symptoms more effectively. Better performance of syndrome classification is able to be achieved according to the experimental results and the clinical experts.


Assuntos
Hepatite Viral Humana/classificação , Humanos , Medicina Tradicional Chinesa
11.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 15(6): 1169-72, 2007 Dec.
Artigo em Zh | MEDLINE | ID: mdl-18088459

RESUMO

This study was purpose to investigate the expression levels of HSP70 and MDR1 genes under heat shock and/or adriamycin (ADM) chemotherapy stimulation. The K562 cells were bathed in water at 43 degrees C for 1 hour, then the heat-treated K562 cells were collected and were cultured at 37 degrees C. The expression of HSP70 was assayed by immunocytochemistry, the growth suppression rate of K562 cells was detected by MTT assay, the function of P-gp and the expressions of HSP70 mRNA, MDR1 mRNA were detected by flow cytometry and real-time quantitative PCR (RT-PCR) respectively. The results showed that (1) the synthesis of HSP70 protein in K562 cells treated with high shock (43 degrees C) reached to high level after culture at 37 degrees C for 2 hours, and moved from cytoplasm to nucleolus, the expression of HSP70 began to decrease following 3 hours of culture at 37 degrees C, and gradually reached to normal level after culture at 37 degrees C for 5 hours, the location of HSP70 expression returned to cytoplasm; (2) the expressions of HSP70 mRNA and MDR1 mRNA increased following 43 degrees C heat shock, and were 4 and 5.8 times higher than that of control group at 37 degrees C culture for 2 hours respectively; (3) the expression of P-gp was higher in ADM group than that in control. The expressions of HSP mRNA and MDR1 mRNA increased significantly in heat shock plus ADM group and ADM group as compared with control (p<0.01). It is concluded that the heat shock and ADM chemotherapy both induce over expression of HSP70 and MDR1 which can maintain stability of K562 cells and may be related to formation of the MDR in leukemia.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Doxorrubicina/farmacologia , Proteínas de Choque Térmico HSP70/metabolismo , Resposta ao Choque Térmico , Antibióticos Antineoplásicos/farmacologia , Proliferação de Células , Humanos , Células K562 , RNA Mensageiro/metabolismo
12.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 14(3): 468-70, 2006 Jun.
Artigo em Zh | MEDLINE | ID: mdl-16800922

RESUMO

To explore a rapid and easy method to detect labile iron of pool (LIP) in cells, HL-60 and K562 cells were cultured at a concentration 1 x 10(6)/ml in RPMI 1640 containing 10% heat-inactivated fetal bovine serum. The iron deprivation was induced by adding desferrioxamine (DFO) 10 - 100 micromol/L for 0 - 48 hours. The intracellular LIP was measured by probe calcein-AM. Calcein fluorescence was monitored in 1420 multilabel counter. The results indicated that when HL-60 and K562 cells were incubated with different concentrations of DFO, the calcein fluorescence intensity was higher than that of control group at 12, 24 and 48 hours (P < 0.05). Fluorescence value of representing LIP in DFO groups was lower than that in the control group. In conclusion, DFO can decrease LIP in leukemia cells. The approach used in this study may provide a simple and reliable method for detection of intracellular iron homeostasis.


Assuntos
Proteínas de Transporte de Cátions/metabolismo , Quelantes de Ferro/análise , Proteínas Reguladoras de Ferro/metabolismo , Ferro/metabolismo , Proteínas de Transporte de Cátions/antagonistas & inibidores , Proteínas de Transporte de Cátions/biossíntese , Desferroxamina/farmacologia , Fluoresceínas , Corantes Fluorescentes , Células HL-60 , Humanos , Quelantes de Ferro/metabolismo , Células K562
13.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 13(6): 964-8, 2005 Dec.
Artigo em Zh | MEDLINE | ID: mdl-16403260

RESUMO

The objective of this study was to investigate antineoplastic effects of valproic acid (VPA) and trichostatin (TSA) on HL-60 and K562 cells in vitro, and the synergic effects of VPA or TSA in combination with ATRA. The inhibitory effects of VPA, TSA and ATRA in various concentrations and different combinations on proliferation of HL-60 and K562 cells were observed by cell growth curves, 50% inhibitory concentration (IC(50)), as well as inhibition of leukemia colony growth at different time points. The characteristics of cell differentiation or apoptosis were analyzed by cytochemical staining, differentiation antigen detection, cell cycle assay and A(NBT)/A(MMT) value determination. The results showed that HL-60 cell had a lower IC(50) of VPA and TSA compared with K562 cells. ATRA could significantly enhance the inhibition of VPA, TSA on clonegenicity of HL-60 cells and inhibition of VPA on clonegenicity of K562 cells. HL-60 cells treated with VPA displayed the phenotype of neutrophilic like cells, and showed the increases of NBT reduction rate and CD11b expression. No evidence for K562 differentiation was found. It is concluded that both VPA and TSA inhibit HL-60 cells growth in vitro. VPA induces differentiation of HL-60 cells to granulocyte. VPA and TSA have a moderate anti-proliferative effect on K562 cells. None of these agents induces K562 cell differentiation.


Assuntos
Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Ácidos Hidroxâmicos/farmacologia , Ácido Valproico/farmacologia , Sinergismo Farmacológico , Células HL-60 , Inibidores de Histona Desacetilases , Humanos , Concentração Inibidora 50 , Células K562
14.
Zhonghua Xue Ye Xue Za Zhi ; 24(4): 181-4, 2003 Apr.
Artigo em Zh | MEDLINE | ID: mdl-12864947

RESUMO

OBJECTIVE: To explore the effect of T(3) on the expression of transferrin receptor (TfR) and ferritin (Fn) in K562 cells and its possible mechanism. METHODS: Flow cytometry was used for the detection of TfR expression, radioimmunoassay for Fn expression, RNA/protein band shift assay for the binding activity of iron regulatory protein (IRP) and iron responsive elements (IRE), and RT-PCR for TfR and Fn mRNA levels. RESULTS: Different concentration of T(3) significantly increased Fn expression of K562 cells, especially at 100 nmol/L and 200 nmol/L (p < 0.05). However, T(3) had no effect on TfR expression. T(3) decreased the binding activity between IRP and IRE, particularly at concentration of 50 nmol/L. Different concentration of T(3) increased Fn-H mRNA level at different time point while it had no effect on TfR mRNA level. CONCLUSION: T(3) increased Fn expression of K562 cells through the possible mechanisms of either the post-transcriptional regulation or transcriptional modulation.


Assuntos
Ferritinas/biossíntese , Receptores da Transferrina/biossíntese , Tri-Iodotironina/farmacologia , Ferritinas/efeitos dos fármacos , Ferritinas/genética , Citometria de Fluxo , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Células K562 , RNA Mensageiro/genética , Radioimunoensaio , Receptores da Transferrina/efeitos dos fármacos , Receptores da Transferrina/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
Zhonghua Er Ke Za Zhi ; 41(7): 528-30, 2003 Jul.
Artigo em Zh | MEDLINE | ID: mdl-14746681

RESUMO

OBJECTIVE: Functionally, erythropoietin (EPO) can promote the proliferation and growth of erythroid progenitor cells, and it is widely used in the treatment of anemia in chronic diseases caused by tumor and inflammation. However, it is unclear whether EPO has any effect on tumor cell iron metabolism and tumor cell proliferation. The purpose of this study was to explore the effects of recombinant human EPO (rhEPO) on the expression of transferrin receptor (TfR, CD(71) antigen) of leukemic cell K562 and its relation to cell cycle. METHODS: In vitro culture of K562 cell was performed with additions of various concentrations of rhEPO and Fe. Treatments were terminated at 24 h and 72 h, respectively. Then each group of cells was incubated with FITC-IgG antibody to CD(71) or PI, a kind of DNA dye. And TfR expression and DNA synthesis status were analyzed by flow-cytometry. RESULTS: (1) The expression of TfR by K562 cells increased significantly when incubated for 72 h with different concentrations of rhEPO. The measurement values of 5 U/ml, 10 U/ml and 20 U/ml groups were 12.2 +/- 1.40, 10.7 +/- 0.99 and 11.1 +/- 0.90, respectively. They were markedly increased when compared with that of control group (6.27 +/- 0.11, P < 0.05). (2) When incubated with rhEPO (5 u/ml) alone or combined with FeCl(3) (100 micro mol/L), the percentages of cells in S phase were 51.1% and 59.6%, respectively. They significantly increased when compared with that of control group (42.9%, P < 0.05). CONCLUSIONS: Iron is very important for the proliferation of both normal cells and leukemic cells. It is essential to the activity of ribonucleotide reductase (RR). The authors hypothesized that rhEPO would increase the expression of TfR and intracellular iron content of leukemic cells, which would enhance the DNA synthesis and cell proliferation. Therefore, the clinical application of rhEPO to promote erythropoiesis of cancer patients should be cautious.


Assuntos
Eritropoetina/farmacologia , Receptores da Transferrina/metabolismo , Ciclo Celular/efeitos dos fármacos , Citometria de Fluxo , Humanos , Células K562 , Proteínas Recombinantes
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