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1.
Cell Death Differ ; 23(8): 1347-57, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26915297

RESUMO

Deafness or hearing loss is a major issue in human health. Inner ear hair cells are the main sensory receptors responsible for hearing. Defects in hair cells are one of the major causes of deafness. A combination of induced pluripotent stem cell (iPSC) technology with genome-editing technology may provide an attractive cell-based strategy to regenerate hair cells and treat hereditary deafness in humans. Here, we report the generation of iPSCs from members of a Chinese family carrying MYO15A c.4642G>A and c.8374G>A mutations and the induction of hair cell-like cells from those iPSCs. The compound heterozygous MYO15A mutations resulted in abnormal morphology and dysfunction of the derived hair cell-like cells. We used a CRISPR/Cas9 approach to genetically correct the MYO15A mutation in the iPSCs and rescued the morphology and function of the derived hair cell-like cells. Our data demonstrate the feasibility of generating inner ear hair cells from human iPSCs and the functional rescue of gene mutation-based deafness by using genetic correction.


Assuntos
Células Ciliadas Auditivas Internas/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Miosinas/genética , Sequência de Bases , Sistemas CRISPR-Cas/genética , Diferenciação Celular , Reprogramação Celular , Pré-Escolar , Derme/citologia , Feminino , Fibroblastos/citologia , Fibroblastos/metabolismo , Fator de Transcrição GATA3/genética , Fator de Transcrição GATA3/metabolismo , Células Ciliadas Auditivas Internas/citologia , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Masculino , Mutação , Miosinas/metabolismo , Fator de Transcrição PAX2/genética , Fator de Transcrição PAX2/metabolismo , Fator de Transcrição PAX8/genética , Fator de Transcrição PAX8/metabolismo , Linhagem , Polimorfismo de Nucleotídeo Único , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
2.
ACS Appl Mater Interfaces ; 8(5): 3516-23, 2016 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-26824841

RESUMO

N-Halamine antibacterial materials have superior inactivation activities due to oxidative chlorine species. However, N-Cl bonds and bonds between N-halamine and substrates often decompose rapidly under UV irradiation, leading to unrecoverable loss of antimicrobial activity. In this study, titanium dioxide was covalently bonded onto N-halamine siloxane poly[5,5-dimethyl-3-(3'-triethoxysilylpropyl)hydantoin] (PSPH) via a sol-gel process. Experimental testing of the chlorinated cotton fabrics treated with TiO2/PSPH demonstrated that the residual oxidative chlorine in cotton-TiO2/PSPH-Cl was still effective for inactivating bacteria after 50 washing cycles and under UV light irradiation for 24 h. Quantum mechanical calculations found that TiO2 improves the UV stability of the PSPH-Cl system by increasing the activation barrier of the C-Si scission reaction responsible for the loss of the biocidal hydantoin moiety. SEM, XPS and FTIR spectra were used to characterize the coated cotton samples. Cotton-TiO2/PSPH-Cl samples exhibited good antibacterial activity against Staphylococcus aureus (ATCC 6538) and Escherichia coli O157:H7 (ATCC 43895). The storage stability and washing stability of treated cotton fabrics were also investigated.


Assuntos
Antibacterianos/química , Infecções Bacterianas/prevenção & controle , Materiais Revestidos Biocompatíveis/química , Siloxanas/química , Titânio/química , Antibacterianos/farmacologia , Antibacterianos/efeitos da radiação , Materiais Revestidos Biocompatíveis/efeitos da radiação , Materiais Revestidos Biocompatíveis/uso terapêutico , Fibra de Algodão , Escherichia coli O157/efeitos dos fármacos , Escherichia coli O157/patogenicidade , Humanos , Hidantoínas/química , Fotólise , Siloxanas/uso terapêutico , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/patogenicidade , Têxteis/microbiologia , Titânio/uso terapêutico , Raios Ultravioleta
3.
J Viral Hepat ; 20(10): 729-43, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24010648

RESUMO

The efficacy of adjuvant interferon treatment for the management of patients with viral hepatitis-related hepatocellular carcinoma (HCC) following curative treatment is controversial. We have conducted a systematic review with meta-analysis to assess the effects of adjuvant interferon therapy on survival outcomes. Randomized and nonrandomized studies (NRSs) comparing adjuvant interferon treatment with the standard of care for viral hepatitis-related HCC after curative treatment were included. CENTRAL, Medline, EMBASE and the Science Citation Index were searched with complementary manual searches. The primary outcomes were recurrence-free survival (RFS) and overall survival (OS). Nine randomized trials and 13 NRSs were included in the meta-analysis. These nine randomized trials included 942 participants, of whom, 490 were randomized to the adjuvant interferon treatment group and 452 to the control group. The results of meta-analysis showed unexplained heterogeneity for both RFS and OS. The 13 NRSs included 2214 participants, of whom, 493 were assigned to the adjuvant interferon treatment group and 1721 to the control group. The results of meta-analysis showed that, compared with controls, adjuvant interferon treatment significantly improved the RFS [hazard ratio (HR) 0.66, 95% confidence interval (CI) 0.52-0.84, I(2) = 29%] and OS (HR 0.43, 95% CI 0.34-0.56, I(2) = 0%) of patients with hepatitis C virus-related HCC following curative treatment. There was little evidence for beneficial effects on patients with hepatitis B virus-related HCC. Future research should be aimed at clarifying whether the effects of adjuvant interferon therapy are more prominent in hepatitis C patients with sustained virological responses.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Hepatite B/complicações , Hepatite C/complicações , Fatores Imunológicos/uso terapêutico , Interferons/uso terapêutico , Carcinoma Hepatocelular/cirurgia , Humanos , Análise de Sobrevida , Resultado do Tratamento
4.
Infection ; 37(2): 96-102, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19139810

RESUMO

BACKGROUND: Individuals with end-stage renal disease (ESRD) are 10- to 25-fold more likely than immunocompetent people to develop active tuberculosis (TB) and are candidates for being treated for latent TB infection (LTBI). However, diagnosis using the tuberculin skin test (TST) is doubly difficult due to cutaneous anergy and cross-reactions with Bacille-Calmette-Guérin (BCG) vaccination. MATERIALS AND METHODS: This was a prospective, doublematched, cohort study in which 32 ESRD patients and 32 age-matched, healthy controls were enrolled. The TST and two new interferon-gamma blood tests, QuantiFERON-TB Gold (QFT-G) and T-SPOT.TB (ELISPOT), were performed. The subjects were followed up 2 years for active TB disease. ELISPOT was done in ESRD patients only. RESULTS: Compared to the healthy controls, a high prevalence of LTBI was found in the ESRD patients by TST (62.5%, 95% confidence interval [CI] 43.7-78.9), QFT-G (40.0%, 95% CI 22.7-59.4), and ELISPOT (46.9%, 95% CI 29.1-65.3). Agreement was moderate (kappa [kappa] = 0.53) for QFT-G and ELISPOT but only slight between TST and QFT-G (kappa = 0.25) and fair between TST and ELISPOT (kappa = 0.32). ESRD (p = 0.03) and diabetes mellitus (p = 0.04) were significant risk factors for QFT-G positivity on the multivariable analysis. The overall rate of active TB was 1.66 cases per 100 person-years (pys), with the rate higher in patients with ESRD (3.53 per 100 pys) and those with positive (3.40 per 100 pys) and indeterminate QFT results (30.16 per 100 pys), although the difference was not statistically significant. Sensitivity, specificity, and positive and negative predictive values of QFT-G for active TB was 100%, 62.1%, 8.3% and 100%. CONCLUSION: This pilot study is the first to compare QFT-G, ELISPOT, and TST in ESRD patients on hemodialysis and demonstrates a high prevalence of LTBI in this population. In our study, the QFT-G was the more accurate method for identifying those truly infected with Mycobacterium tuberculosis, even in BCG-vaccinated individuals.


Assuntos
Técnicas Imunoenzimáticas , Falência Renal Crônica/complicações , Diálise Renal , Teste Tuberculínico , Tuberculose/diagnóstico , Adulto , Idoso , Distribuição de Qui-Quadrado , Estudos de Coortes , Feminino , Humanos , Interferon gama/sangue , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis , Estudos Prospectivos , Recidiva , Tuberculose/complicações , Tuberculose/microbiologia
5.
Arch Virol ; 150(6): 1101-19, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15703847

RESUMO

Two envelope glycoprotein (Erns and E2) regions of the classical swine fever virus (CSFV) were amplified by RT-PCR and sequenced directly from 158 specimens collected between 1989 and 2003 in Taiwan. Phylogenetic analysis of the two regions revealed a similar tree topology and the Erns region provided better discrimination than the E2 region. One hundred and fifteen isolates out of the 158 isolates were clustered within subgroup 2.1 (further classified as 2.1a and 2.1b) and 2.2, which were considered to be likely of the introduced strains, whereas the remaining 43 isolates were clustered within subgroup 3.4 and were considered to be of the endemic strains. The subgroup 2.1a viruses were first detected in 1994 and predominated from 1995 onwards. However, subgroup 3.4 viruses were prevalent in the early years, not being isolated after 1996. We have observed a dramatic switch in genotype from subgroup 3.4 to 2.1a. The subgroup 2.1a isolates are closely related to the Paderborn and Lao isolates, whereas 2.1b isolates have a close relationship to the Chinese Guangxi isolates. The phylogenetic tree of 27 CSFV sequences based on the complete envelope glycoprotein gene (Erns-E2) displayed better resolution than that based on the complete open reading frame.


Assuntos
Vírus da Febre Suína Clássica/classificação , Vírus da Febre Suína Clássica/genética , Peste Suína Clássica/epidemiologia , Peste Suína Clássica/virologia , Filogenia , Animais , DNA Viral/análise , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Taiwan/epidemiologia , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/genética
6.
Eur J Clin Microbiol Infect Dis ; 21(10): 706-9, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12415468

RESUMO

A 69-year-old man with Sweet's syndrome and myelodysplastic syndrome presented with pneumonia and respiratory distress. He had been taking corticosteroids and methotrexate. The diagnosis of Legionnaires' disease was established by the isolation of Legionella pneumophila serogroup 6 from sputum and a fourfold seroconversion of Legionella antibodies to 1:512. Legionella pneumophila serogroup 6 was isolated from faucets in two homes owned by the patient. Strains of Legionella pneumophila serogroup 6 isolated from the patient's sputum and from one home were demonstrated to be genetically identical by pulsed-field gel electrophoresis but different from strains found in the other home and in a hospital outpatient clinic that he visited. This case illustrates an emerging public health issue concerning acquisition of community-acquired Legionnaires' disease from the homes of immunocompromised hosts. This is the first such case reported in Asia.


Assuntos
Infecções Comunitárias Adquiridas/diagnóstico , Infecções Comunitárias Adquiridas/etiologia , Hospedeiro Imunocomprometido , Legionella pneumophila/isolamento & purificação , Doença dos Legionários/diagnóstico , Abastecimento de Água , Idoso , China , Infecções Comunitárias Adquiridas/imunologia , DNA Bacteriano/análise , Eletroforese em Gel de Campo Pulsado , Seguimentos , Humanos , Doença dos Legionários/imunologia , Masculino , Síndromes Mielodisplásicas/imunologia , Radiografia Torácica , Medição de Risco , Síndrome de Sweet/imunologia , Microbiologia da Água
7.
Mol Pharmacol ; 60(4): 768-75, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11562439

RESUMO

GL331 is a novel podophyllotoxin-derived compound. In this study, GL331 induced human lung adenocarcinoma cell line CL1-5 growth arrest before death during the initial 24-h incubation period. We found that GL331 had no inhibitory effect on the expression of cyclins E, A, B1, CDK 4, and CDK 2; instead, its cell growth-inhibitory effect was partly attributable to an early down-regulation of cyclin D1 expression and in turn the reduction of retinoblastoma protein phosphorylation. GL331 enhanced the proteolysis of cyclin D1, and a proteasome inhibitor was able to block GL331-caused cyclin D1 reduction, suggesting that GL331-stimulated cyclin D1 degradation was through proteasomal processes. Additionally, GL331 reduced cellular cyclin D1 mRNA level down to 45% of control in 4 h and further to around 20% in 12 h. However, GL331 did not accelerate the disappearance of cyclin D1 mRNA under the condition of transcription blockage induced by actinomycin D. It was reported that a certain region in the 3'-untranslated region (UTR) of cyclin D1 mRNA mediated the mRNA degradation upon extracellular stresses. Herein, transient transfection studies demonstrated that the 3'-UTR insertion did not confer the susceptibility of luciferase reporter gene to the GL331 treatment. Together, these data suggested that GL331 did not decrease the stability of cyclin D1 mRNA. On the other hand, we found that GL331 specifically inhibited the cyclin D1 promoter-driven luciferase reporter activity. Western blot analyses showed that GL331 decreased the level of phosphorylated extracellular signal-regulated kinase (Erk), with no effect on p38 or c-Jun NH(2)-terminal kinase. Furthermore, GL331's inhibition of cyclin D1 promoter was attenuated by ectopic Erk-2 overexpression. These data suggested that GL331 inhibited cyclin D1 gene transcription via the Erk signaling pathway. In summary, we report that GL331 induced an early decline of cyclin D1 expression by dual mechanisms: 1) enhancement of protein turnover and 2) repression of Erk-mediated gene transcription.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Ciclina D1/genética , Etoposídeo/farmacologia , Proteínas Proto-Oncogênicas , Transcrição Gênica/efeitos dos fármacos , Ciclina D1/metabolismo , Quinase 4 Dependente de Ciclina , Quinases Ciclina-Dependentes/metabolismo , Regulação para Baixo/efeitos dos fármacos , Etoposídeo/análogos & derivados , Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Regiões Promotoras Genéticas/efeitos dos fármacos , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas , Proteínas Quinases p38 Ativadas por Mitógeno
8.
Life Sci ; 69(11): 1269-84, 2001 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-11521751

RESUMO

Humic acid (HA) is a fluorescent deep brown organic, polymeric compound composed of phenolic acid. Intraperitoneal injection of HA in rats induced testicular morphological changes including degeneration of the seminiferous tubule, reduction in the number of Sertoli cells and spermatogonia, and a loss of spermatids. It was suggested that Sertoli cells may be involved in the progression of testicular atrophy. In this study, we used a mouse Sertoli cell Line, TM4, to investigate the effect of HA on Sertoli cells and the mechanism of the testicular atrophy induced by HA. We found that the cell growth of TM4 cells were reduced in 1 to 4 days of HA exposure. FACScan analysis of the DNA content of HA-treated TM4 cells revealed that there was no sub-G1 peak, indicating that the TM4 cells did not commit to the programmed cell death. However, a large proportion of TM4 cells were arrested at the G1 phase. The percentage of TM4 cells at the G1 phase increased from 36% to 84% after HA treatment for 4 days. Western blot assay of HA-treated TM4 cells showed that the expression of cyclin D1 protein decreased while the expression of p27kiP1 protein increased. These results suggest that HA-induced testicular atrophy is linked in part to an inhibitory effect on the growth of Sertoli cells. This model may be useful in investigation of environmental agents inducing testicular atrophy.


Assuntos
Substâncias Húmicas/toxicidade , Células de Sertoli/efeitos dos fármacos , Proteínas Supressoras de Tumor , Animais , Western Blotting , Contagem de Células , Proteínas de Ciclo Celular/metabolismo , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Ciclina D1/biossíntese , Inibidor de Quinase Dependente de Ciclina p27 , DNA/biossíntese , Citometria de Fluxo , Fase G1/efeitos dos fármacos , Masculino , Camundongos , Células de Sertoli/metabolismo , Células de Sertoli/patologia
9.
Pharm Res ; 18(6): 846-51, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11474790

RESUMO

PURPOSE: Topoisomerase II (Topo II) preferentially cuts DNA at alternating purine-pyrimidine repeats. Different Topo II poisons may affect Topo II to produce distinct drug-specific DNA cleavage patterns. GL331 is a new podophyllotoxin derivative exhibiting potent Topo II-poisoning activity. Therefore, the sequence selectivity of GL331-induced DNA cleavage was determined. METHODS: Human gastric adenocarcinoma SC-M1 cells were treated with GL331, and the resultant DNA fragments were isolated by SDS-K+ precipitation. These DNA fragments were further cloned and sequenced to exhibit GL331-induced DNA cleavage sites. In addition, the telomere damage was detected by Southern blot analyses using a (TTAGGG)4 probe. GL331's effect on telomerase was examined using the TRAP assay. RESULTS: The selective sequences of GL331-induced DNA cleavage were analyzed. The first nucleotide 3'-terminal to the cleavage sites was preferentially C or G and followed by the second nucleotide T. More than 50% of GL331-induced DNA cleavage fragments exhibited AT-rich sequences in the first 20 nucleotides. In addition, the telomeric damage was observed both from GL331-treated SC-M1 cells and in vitro incubation of genomic DNA with GL331 and purified human Topo II. Although GL331 treatment reduced cellular telomerase activity, in vitro reaction data suggested that GL331 was not a telomerase inhibitor. CONCLUSION: GL331 preferentially induced Topo II-mediated DNA cleavage at (C/G)T sites. Because the telomeric repeat sequence contains GL331's GT preference site, the telomere was identified as one of the targets of GL331-induced DNA damage.


Assuntos
Antineoplásicos Fitogênicos/toxicidade , Sequência de Bases/efeitos dos fármacos , Dano ao DNA , DNA Topoisomerases Tipo II/metabolismo , Etoposídeo/análogos & derivados , Etoposídeo/toxicidade , Substâncias Intercalantes/toxicidade , Telômero/efeitos dos fármacos , Humanos , Telomerase/metabolismo , Telômero/enzimologia , Telômero/genética , Telômero/metabolismo , Células Tumorais Cultivadas
10.
Anticancer Drugs ; 12(3): 259-66, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11290873

RESUMO

Combination of selecting agents that act on different cellular mechanisms is a common strategy in cancer chemotherapy. GL331 is a new potent topoisomerase II (Topo II) poison; distinctly, paclitaxel is a microtubule-interfering cancer chemotherapeutic agent. In this study, we intended to evaluate the efficacy of combining GL331 with paclitaxel in cell killing and apoptotic induction in nasopharyngeal carcinoma NPC-TW01 cells. By MTT and internucleosomal DNA cleavage assays, we found that pretreatment or simultaneous treatment of NPC-TW01 cells with GL331 could significantly interfere with paclitaxel's cell killing and apoptosis-inducing activity. When the administration schedule was reversed, the cytotoxicity of GL331 was attenuated by paclitaxel pretreatment. The anti-cancer activity produced by combining GL331 with paclitaxel was obviously lower than the addition of the activities of two individual agents. NPC-TW01 cells were treated with GL331 and 3H-labeled paclitaxel simultaneously or with GL331 before 3H-labeled paclitaxel. In both conditions, GL331 did not reduce the [3H]paclitaxel level in the cells, suggesting that GL331's interference with paclitaxel's cell-killing and apoptosis-inducing efficacy did not result from any inhibition of cellular uptake or retention of paclitaxel. In addition, we found that GL331-induced perturbation of cell cycle progression dramatically over-rode the patterns of mitotic arrest induced by paclitaxel, and the mechanism could be the inhibition of cyclin B1/CDC2 kinase and MAD2 checkprotein activities.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Proteínas de Transporte , Ciclo Celular/efeitos dos fármacos , Neoplasias Nasofaríngeas/tratamento farmacológico , Células Tumorais Cultivadas/efeitos dos fármacos , Antineoplásicos Fitogênicos/administração & dosagem , Western Blotting , Proteína Quinase CDC2/efeitos dos fármacos , Proteína Quinase CDC2/metabolismo , Proteínas de Ligação ao Cálcio/efeitos dos fármacos , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Ciclo Celular , Núcleo Celular/efeitos dos fármacos , Ciclina B/efeitos dos fármacos , Ciclina B/metabolismo , Ciclina B1 , DNA de Neoplasias/análise , Relação Dose-Resposta a Droga , Antagonismo de Drogas , Avaliação de Medicamentos , Interações Medicamentosas , Quimioterapia Combinada , Etoposídeo/administração & dosagem , Etoposídeo/análogos & derivados , Citometria de Fluxo , Proteínas Fúngicas/efeitos dos fármacos , Proteínas Fúngicas/metabolismo , Humanos , Neoplasias Nasofaríngeas/metabolismo , Proteínas Nucleares , Paclitaxel/administração & dosagem , Testes de Precipitina , Proteínas Quinases/metabolismo , Sais de Tetrazólio , Tiazóis , Testes de Toxicidade , Células Tumorais Cultivadas/metabolismo
11.
Ear Nose Throat J ; 80(2): 76-8, 81-2, 84 passim, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11233350

RESUMO

Delayed endolymphatic hydrops (DEH) differs from Ménière's disease in that it occurs in pre-existing ear pathology in patients who have a profound unilateral or total deafness that was caused by infection, trauma, or unknown causes during childhood or adulthood. We performed a retrospective review of 160 patients with ipsilateral, contralateral, or bilateral DEH. Eighty-seven patients who did not respond to medical therapy underwent surgical treatment. Our findings indicate that the more conservative surgical procedures--endolymphatic sac surgery, cochleosacculotomy, and streptomycin perfusion--are all as effective as and less destructive than labyrinthectomy for controlling vertigo. The clinical results of this study would seem to support the observations of others that DEH and Ménière's disease are related disorders caused predominantly by cases of viral labyrinthitis with unknown etiology.


Assuntos
Surdez/etiologia , Hidropisia Endolinfática/diagnóstico , Hidropisia Endolinfática/cirurgia , Procedimentos Cirúrgicos Otológicos , Vertigem/etiologia , Adulto , Idade de Início , Idoso , Testes Calóricos , Diagnóstico Diferencial , Hidropisia Endolinfática/complicações , Hidropisia Endolinfática/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
12.
Stem Cells ; 19(1): 1-11, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11209086

RESUMO

In vitro studies of cultured native acute myelogenous leukemia (AML) blasts and cell lines have contributed significantly to our present knowledge about the pathogenesis of AML. In the present article we review different techniques for preparation and in vitro culture of AML blasts. Well-characterized serum-free in vitro conditions can now be used in experimental studies of AML, and this makes comparisons between different studies easier. We also describe assays for characterization of AML progenitor subsets (i.e., suspension cultures, colony assays, long-term in vitro culture, xenotransplantation in immunocompromised mice), and we discuss the possible use of AML cell lines as experimental models in AML. Furthermore, clinical studies suggest that the in vitro growth characteristics of AML blasts assayed by short-term culture of the total native populations can be used as a predictor of prognosis after intensive chemotherapy. These in vitro assays may therefore be used for more accurate identification of prognostic parameters and thereby form a basis for the development of simplified laboratory techniques suitable for routine evaluation of patients undergoing risk-adapted therapy. However, it will be equally important to further evaluate the clinical relevance of assays for primitive AML progenitors, and to develop simplified methods that can be used to characterize these progenitor subsets in the routine clinical evaluation.


Assuntos
Técnicas de Cultura de Células/métodos , Leucemia Mieloide Aguda/terapia , Células-Tronco Neoplásicas/citologia , Humanos , Células Tumorais Cultivadas/citologia
13.
J Formos Med Assoc ; 100(11): 772-5, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11802538

RESUMO

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis has been recently recognized in Graves' disease patients treated with antithyroid drugs. We describe the case of an 18-year-old girl who developed antimyeloperoxidase ANCA (MPO-ANCA)-positive vasculitis manifesting as a skin lesion and hemoptysis with hypoxic respiratory failure after taking methimazole. An open lung biopsy was consistent with acute capillaritis. Both skin and sural nerve biopsy showed lymphocytic vasculitis. Administration of steroid and plasmapheresis produced a good clinical response.


Assuntos
Anticorpos Anticitoplasma de Neutrófilos/análise , Antitireóideos/efeitos adversos , Autoanticorpos/análise , Hemorragia/etiologia , Pneumopatias/induzido quimicamente , Metimazol/efeitos adversos , Peroxidase/imunologia , Vasculite/induzido quimicamente , Adolescente , Feminino , Humanos , Pneumopatias/diagnóstico , Pneumopatias/imunologia , Dermatopatias Vasculares/induzido quimicamente , Dermatopatias Vasculares/diagnóstico , Dermatopatias Vasculares/imunologia , Vasculite/complicações , Vasculite/diagnóstico , Vasculite/imunologia
14.
Vet Microbiol ; 74(3): 207-16, 2000 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-10808089

RESUMO

Sequence diversity was assessed of the complete VP1 gene directly amplified from 49 clinical specimens during an explosive foot-and-mouth disease (FMD) outbreak in Taiwan. Type O Taiwan FMD viruses are genetically highly homogenous, as seen by the minute divergence of 0.2-0.9% revealed in 20 variants. The O/HCP-0314/TW/97 and O/TCP-022/TW/97 viral variants dominated FMD outbreaks and were prevalent in most affected pig-raising areas. Comparison of deduced amino acid sequences around the main neutralizable antigenic sites on the VP1 polypeptide showed no significant antigenic variation. However, the O/CHP-158/TW/97 variant had an alternative critical residue at position 43 in antigenic site 3, which may be due to selective pressure in the field. Two vaccine production strains (O1/Manisa/Turkey/69 and O1/Campos/Brazil/71) probably provide partial heterologous protection of swine against O Taiwan viruses. The type O Taiwan variants clustered in sublineage A1 of four main lineages in the phylogenetic tree. The O/Hong Kong/9/94 and O/1685/Moscow/Russia/95 viruses in sublineage A2 are closely related to the O Taiwan variants. The causative agent for the 1997 epidemic presumably originated from a single common source of type O FMD viruses prevalent in neighboring areas.


Assuntos
Aphthovirus/genética , Surtos de Doenças/veterinária , Febre Aftosa/virologia , Filogenia , Doenças dos Suínos/virologia , Sequência de Aminoácidos , Animais , Aphthovirus/classificação , Aphthovirus/imunologia , Sequência de Bases , Sequência Consenso , Primers do DNA/química , DNA Viral/química , Eletroforese em Gel de Ágar/veterinária , Epitopos/química , Febre Aftosa/epidemiologia , Variação Genética/genética , Dados de Sequência Molecular , RNA Viral/química , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Suínos , Doenças dos Suínos/epidemiologia , Taiwan/epidemiologia , Proteínas Virais/química , Proteínas Virais/genética , Proteínas Virais/imunologia
15.
Apoptosis ; 5(3): 235-41, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11225845

RESUMO

Paclitaxel (Taxol) is a microtubule-interfering agent that induced persistent and transient G2/M arrest before apoptosis in human nasopharyngeal carcinoma (NPC) cells at high and low concentrations, respectively. In this study, we intended to explore the underlying molecular events and found that cellular cyclin B1/CDC 2 kinase activity was increased and persisted for >6 h upon paclitaxel treatment both at high and low concentrations. Furthermore, activation of MAD 2 checkprotein could account for the loss of cyclin B1 ubiquitination and the persistence of cyclin B1/CDC 2 activation in the cases. To investigate the involvement of cyclin B1 and MAD 2 activation in paclitaxel-induced apoptosis, we introduced affinity-purified anti-cyclin B1 and MAD 2 antibodies into NPC cells by electroporation before the further paclitaxel treatment. The antibodies against cyclin B1 and MAD 2 indeed attenuated paclitaxel-induced cytotoxicity and DNA fragmentation. Our study suggests that activation of cyclin B1/CDC 2 and MAD 2 were the M-phase events required for paclitaxel-induced apoptosis in NPC cells. The dys-regulated cyclin B1/CDC 2 activation could enhance the prometaphase progression, but activation of MAD 2 rendered cells inable to exit from the metaphase. Under this circumstance, cells were probably going to "mitotic catastrophe" and ultimately, destined to apoptosis.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose , Proteína Quinase CDC2/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Transporte , Proteínas de Ciclo Celular/metabolismo , Ciclina B/metabolismo , Proteínas Fúngicas/metabolismo , Neoplasias Nasofaríngeas/patologia , Paclitaxel/farmacologia , Anticorpos/imunologia , Western Blotting , Ciclo Celular/fisiologia , Ciclina B1 , Fragmentação do DNA , Eletroporação , Humanos , Modelos Biológicos , Neoplasias Nasofaríngeas/metabolismo , Proteínas Nucleares , Testes de Precipitina , Células Tumorais Cultivadas
16.
Apoptosis ; 5(1): 79-85, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11227495

RESUMO

GL331 is a novel podophyllotoxin-derived compound and is more efficacious than its congener VP-16 in killing several types of cancer cells, that has promoted considerable interest in its possibility of clinical use. In this study, we found that the higher cytotoxicity of GL331 in nasopharyngeal carcinoma NPC-TW01 cells was attributed to the elevated ability to induce apoptotic cell death. In addition to evaluation of GL331's single agent activity, the use of GL331 in combination with other established therapeutic agents was also evaluated. We found that GL331-induced cell cycle perturbation occurred upon initial 8-h exposure, and pretreatment of NPC-TW01 cells with GL331 for 8 h significantly interfered with the cytotoxicities of VP-16, cisplatin, 5-fluorouracil and adriamycin. When the schedule of drug administration was reversed, high-toxic concentrations of these agents revealed an antagonistic effect on GL331; however, their low-toxic doses had the additive or even more-than-additive effect on the cytotoxicity induced by GL331 at 0.1 microM or less, but for GL331 concentrations of greater than 1 microM, the effect became less than additive. These data suggest that overlapping mechanisms could be elicited by GL331 and other agents, and additional preclinical studies are needed to determine the optimal dose combination and administration schedule that will enhance, rather than interfere with, the efficacy of GL331 in combination with other anti-cancer agents.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Carcinoma/tratamento farmacológico , Etoposídeo/farmacologia , Neoplasias Nasofaríngeas/tratamento farmacológico , Antineoplásicos Fitogênicos/toxicidade , Cisplatino/farmacologia , Relação Dose-Resposta a Droga , Doxorrubicina/farmacologia , Interações Medicamentosas , Quimioterapia Combinada , Etoposídeo/análogos & derivados , Etoposídeo/toxicidade , Fluoruracila/farmacologia , Testes de Toxicidade , Células Tumorais Cultivadas
17.
Pharm Res ; 16(7): 997-1002, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10450922

RESUMO

PURPOSE: GL331 is a new homolog of VP-16, and has demonstrated more efficacious anti-cancer activity in both the in vitro and in vivo lymphoma systems. To extensively explore GL331's clinical value, we furthermore evaluate the cytotoxicity and apoptosis-inducing activity of GL331 in several human cell lines from cancers that are not normally treated with VP-16. METHODS: By MTT and clonogenic survival assays, the cytotoxicities of GL331 and VP-16 were evaluated in a variety of cell lines including nasopharyngeal, hepatocellular, gastric, colon, cervical, and neuroblastoma cancer types. Western blot analysis was performed to detect the MDR-1 level in these cell lines. By Annexin V-staining flow cytometry and detection of DNA ladders, the apoptosis-inducing activities of GL331 and VP-16 were also evaluated. RESULTS: GL331 showed more efficacy than its congener VP-16 in killing cancer cells. The estimated ID50 of GL331 were 2.5 to 17-fold lowerthan those of VP-16. GL331 possessed more cell-killing activity even in MDR-1-overexpressing cell lines such as HCC36 and SW620. Its higher cytotoxicity could be attributed by the elevated ability to induce apoptotic cell death. CONCLUSION: GL331's overriding drug resistance and higher cancer cell-killing activity suggest its superiority in clinical cancer therapy.


Assuntos
Antineoplásicos Fitogênicos/toxicidade , Etoposídeo/análogos & derivados , Etoposídeo/toxicidade , Neoplasias/tratamento farmacológico , Podofilotoxina/análogos & derivados , Podofilotoxina/toxicidade , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/biossíntese , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Apoptose/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Resistência a Múltiplos Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Etoposídeo/farmacologia , Humanos , Neoplasias/metabolismo , Células Tumorais Cultivadas
18.
Cancer Lett ; 139(1): 1-6, 1999 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-10408900

RESUMO

Cyclin A is an S and G2/M phase regulatory protein and associates with Skp 2 in many transformed cells. Our previous results showed that 12 (39%) and 17 (55%) out of 31 hepatocellular carcinoma (HCC) patients exhibited higher protein expression levels of cyclin A and Skp 2, respectively, in their tumorous compared to non-tumorous tissues. In the present study, we used Western blot analysis to show that 3 out of 6 HCC cell lines, HA59T, HA22T and HCC36, exhibited overexpression of cyclin A, among which the HCC36 cell line also expressed a higher Skp 2 protein level. Moreover, we used the antisense oligonucleotide phosphorothioates to down regulate the overexpression of cyclin A and Skp 2 proteins to determine whether or not these two proteins are involved in the mitogenesis of HCC36 cells. After treatment with antisense oligonucleotide phosphorothioates, the gene product of cyclin A or Skp 2 was suppressed dose-dependently as revealed by Western blot analyses. By [3H]thymidine incorporation assay, we found that downregulation of cyclin A but not Skp 2 overexpression could inhibit the DNA synthesis ability of HCC36 cells, suggesting that abnormal Skp 2 expression is not directly correlated with the HCC proliferation.


Assuntos
Carcinoma Hepatocelular/metabolismo , Proteínas de Ciclo Celular/metabolismo , Ciclina A/metabolismo , DNA de Neoplasias/biossíntese , Regulação para Baixo , Relação Dose-Resposta a Droga , Humanos , Oligonucleotídeos Antissenso , Proteínas Quinases Associadas a Fase S , Células Tumorais Cultivadas
19.
J Cell Physiol ; 179(2): 218-25, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10199561

RESUMO

Humic acid, a high-molecular-weight polyphenolic compound, exists abundantly in soil, natural water, and various terrestrial and aquatic environments. Humic acid causes peroxisome proliferation in mouse liver and induces the expression of peroxisome proliferator activated receptor (PPAR) in BNL CL.2 cells. Both cytotoxicity and flow cytometry show that humic acid inhibits the growth of C3H10T1/2 cells at G1 phase. C3H10T1/2 fibroblast cells express PPARgamma and the adipocyte P2 (aP2) genes which convert into adipocytes after being treated with humic acid. Our findings may provide a unique model for studying the molecular control of determination and differentiation of mesodermal cell lineages.


Assuntos
Substâncias Húmicas/farmacologia , Microcorpos/metabolismo , Receptores Citoplasmáticos e Nucleares/biossíntese , Fatores de Transcrição/biossíntese , Adipócitos/efeitos dos fármacos , Animais , Contagem de Células/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Fase G1 , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Genes Reporter , Fígado/enzimologia , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C3H , RNA Mensageiro/metabolismo , Ativação Transcricional/genética
20.
Am J Otol ; 20(2): 233-7, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10100528

RESUMO

OBJECTIVE: This study aimed to describe the rationales for and preliminary results of three new types of surgery for the treatment of intractable Meniere's disease, all involving insertion of a capillary tube into the endolymphatic duct. This study also aimed to compare the contrasting surgical strategies of endolymphatic sac enhancement versus sac supplantation. STUDY DESIGN AND SETTING: The study design was a retrospective review of 129 surgeries conducted by the author at Chang Gung Memorial Hospital since 1993: 51 cases of Huang/Gibson inner ear shunt implantation, 52 cases of intraductal capillary tube implantation (ICTI), and 26 cases of ICTIin combination with endolymphatic sac ballooning surgery (ESBS). PATIENTS: This study is limited to patients with classic Meniere's disease whose vertiginous symptoms were disabling and refractory to dietetic and medical treatment. MAIN OUTCOME MEASURES: Comparison of preoperative and postoperative conditions (e.g., vertigo control, hearing, disability) using American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) 1985 criteria and chi-square statistical method was measured. RESULTS: After 1 year of follow-up, use of the Huang/Gibson shunt resulted in a 94.1% vertigo control rate (complete or substantial) and fairly good hearing results, ICTI by itself resulted in an 88.5% rate of vertigo control and relatively unremarkable hearing results, and the ICTI in combination with ESBS (ICTI/ESBS) achieved a vertigo control rate of 96.1% in addition to good hearing results. CONCLUSIONS: The 1-year follow-up results for Huang/Gibson shunt implantation and sac-preserving ICTI/ESBS have approximately duplicated the excellent performance of the Arenberg implant after the same follow-up period, perhaps attributable in part to enhancement of endolymph flow through the endolymphatic duct.


Assuntos
Doença de Meniere/cirurgia , Adulto , Idoso , Cateterismo , Ducto Endolinfático/cirurgia , Anastomose Endolinfática/métodos , Feminino , Seguimentos , Transtornos da Audição/diagnóstico , Transtornos da Audição/etiologia , Humanos , Masculino , Doença de Meniere/complicações , Doença de Meniere/diagnóstico , Pessoa de Meia-Idade , Cuidados Pós-Operatórios , Cuidados Pré-Operatórios , Implantação de Prótese , Estudos Retrospectivos , Índice de Gravidade de Doença , Resultado do Tratamento
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