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1.
Stem Cells ; 32(1): 204-15, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24115386

RESUMO

p/CIP, also known as steroid receptor coactivator 3 (SRC-3)/Nuclear Receptor Coactivator 3 (NCoA3), is a transcriptional coactivator that binds liganded nuclear hormone receptors, as well as other transcription factors, and facilitates transcription through direct recruitment of accessory factors. We have found that p/CIP is highly expressed in undifferentiated mouse embryonic stem cells (mESCs) and is downregulated during differentiation. siRNA-mediated knockdown of p/CIP decreased transcript levels of Nanog, but not Oct4 or Sox2. Microarray expression analysis showed that Klf4, Tbx3, and Dax-1 are significantly downregulated in mESCs when p/CIP is knocked down. Subsequent chromatin immunoprecipitation (ChIP) analysis demonstrated that Tbx3, Klf4, and Dax-1 are direct transcriptional targets of p/CIP. Using the piggyBac transposition system, a mouse ESC line that expresses Flag-p/CIP in a doxycycline-dependent manner was generated. p/CIP overexpression increased the level of target genes and promoted the formation of undifferentiated colonies. Collectively, these results indicate that p/CIP contributes to the maintenance of ESC pluripotency through direct regulation of essential pluripotency genes. To better understand the mechanism by which p/CIP functions in ESC pluripotency, we integrated our ChIP and transcriptome data with published protein-protein interaction and promoter occupancy data to draft a p/CIP gene regulatory network. The p/CIP gene regulatory network identifies various feed-forward modules including one in which p/CIP activates members of the extended pluripotency network, demonstrating that p/CIP is a component of this extended network.


Assuntos
Células-Tronco Embrionárias/metabolismo , Coativador 3 de Receptor Nuclear/metabolismo , Células-Tronco Pluripotentes/metabolismo , Animais , Diferenciação Celular , Regulação para Baixo/efeitos dos fármacos , Células-Tronco Embrionárias/citologia , Regulação da Expressão Gênica no Desenvolvimento , Fator 4 Semelhante a Kruppel , Camundongos , Células-Tronco Pluripotentes/citologia , Transfecção
2.
Sci Rep ; 10(1): 6153, 2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32273552

RESUMO

Abundant earthquakes clustered within a particular zone often reflect an active geological feature, such as clustering seismicity along a fault zone and a huge number of volcanic-earthquakes around the erupting conduit. Herein we perform a double-difference tomographic inversion and relocate the seismicity at the long-resting Tatun volcano group (TVG) in northern Taiwan. A dramatic improvement of the earthquake location model surprisingly show that, from 2014 to 2017, two clustered seismic zones are identified in the TVG. One major group of events (>1000) persistently clustered within a ~500 m diameter vertical conduit with a ~2 km height. The clustering seismicity conduit is just located nearby Dayoukeng, one of the strongest fumaroles in the TVG, and is connected to a fracture zone characterized by low Vp/Vs in the shallow crust. The other group of events is clustered within a sphere-like zone beneath Mt. Chihsin around the depths between 0.5 km and 2 km. Both seismic zones are probably triggered by the significantly volcanic gases and fluids ascending from the deep magma reservoir. Combined with a variety of results from literature, the seismicity conduit near the strong fumarole is the evidence for an active volcano and also identifies a likely pathway for ascending magma if the TVG erupts again in the future. But possibility of developing different magma pathways at other clustered seismic zones such as beneath Mt. Chihsin may not be totally excluded.

3.
Cancer Res ; 55(22): 5396-9, 1995 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-7585608

RESUMO

Accumulating evidence implicates the presence of putative tumor suppressor genes on human chromosome 4 that are potentially inactivated in the genesis of several different neoplasms. To accurately determine the frequency of allelic loss on both arms of human chromosome 4, we screened 282 fresh-frozen human bladder carcinomas for allelic loss. Loss of heterozygosity of at least one marker for chromosome 4 was identified in 129 tumors (45.7%). Fine mapping was accomplished using up to 15 polymorphic markers on the p arm and 19 markers on the q arm. We identified a 3-cM minimal area of loss on the p arm between microsatellite markers D4S1608 and D4S404 deleted in 82 tumors (29%). A total of 68 tumors (24%) targeted a 14-cM critical region identified on the distal q arm between markers D4S426 and D4S408. Loss of these two regions correlated with advanced stage and grade of the lesions. These data identify distinct regions of loss on chromosome 4 potentially involved in the late progression of bladder carcinoma.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 4 , Neoplasias da Bexiga Urinária/genética , Mapeamento Cromossômico , Humanos
4.
Cancer Res ; 55(15): 3246-9, 1995 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-7614456

RESUMO

Two hundred eighty-five primary human carcinomas of the urinary bladder were examined for allelic loss on chromosome 14q. Seventeen highly polymorphic dinucleotide markers spanning the long arm of this acrocentric chromosome were selected for fine PCR-based mapping. Loss of heterozygosity for at least one marker was observed in 72 (25.3%) tumors. Thirty-four of these 72 tumors (47.2%) lost the entire long arm (monosomy), as suggested by loss of heterozygosity at all informative sites. Allelic loss on 14q occurred in all grades and stages of bladder cancer but was more commonly associated with muscle-invasive tumors (Ta, 9.4%; T1, 24.1%; and > or = T2, 41%). A deletion map of 16 primary tumors with partial losses delineated two minimal regions of loss. One region (approximately 2 cM) was bounded by markers D14S75 and D14S288 and the other (approximately 3 cM) by D14S51 and D14S267. Our results demonstrate that 14q loss is common in invasive bladder cancer and suggest that two potential suppressor loci at 14q12 and 14q32.1-32.2 may contribute to the genetic progression of this common cancer.


Assuntos
Mapeamento Cromossômico , Cromossomos Humanos Par 14/genética , Deleção de Genes , Genes Supressores , Neoplasias da Bexiga Urinária/genética , Humanos
5.
Endocrinology ; 140(1): 405-15, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9886852

RESUMO

The purpose of this study was to examine whether changes in extracellular matrix (ECM) molecules are associated with the growth inhibition and differentiation defects of the prostate gland following neonatal exposure to estradiol. Using immunocytochemistry (ICC), laminin and collagen IV were localized to the basement membrane (BM) as well to the basal lamina of the periductal smooth muscle of the control developing prostates. In contrast, fibronectin and collagen III were localized throughout the stromal ECM. Exposure to neonatal estrogen altered the staining profile for specific ECM molecules. In the estrogenized rats, a thick layer of cells negative for laminin and collagen IV was observed adjacent to the BM. Electron microscopy and ICC for alpha-actin, fibronectin, and vimentin identified this multicellular layer of periductal cells as differentiated fibroblasts. Peripheral to these fibroblasts, actin-positive smooth muscle formed a second layer of periductal stromal cells. PCNA labeling showed that estrogen exposure increased the fibroblast proliferation. Because many periductal fibroblasts were positive for estrogen receptor alpha (ER alpha) in estrogenized rats, a direct effect of estradiol on their proliferation is suggested. Gelatinolytic gels revealed that estrogen exposure did not alter the activity of matrix metalloproteinases associated with tissue remodeling during prostate morphogenesis. However, the periductal fibroblast layer in estrogenized prostates was devoid of urokinase- and tissue-plasminogen activator, which may potentially alter the localized proteolysis involved in matrix remodeling. It is proposed that proliferation of a multicellular layer of periductal fibroblasts in estrogenized prostates results in a physical barrier that constrains branching morphogenesis and blocks paracrine communications between smooth muscle and epithelial cells which normally regulate differentiation.


Assuntos
Estrogênios/farmacologia , Matriz Extracelular/ultraestrutura , Fibroblastos/efeitos dos fármacos , Próstata/ultraestrutura , Animais , Divisão Celular/efeitos dos fármacos , Matriz Extracelular/efeitos dos fármacos , Feminino , Fibroblastos/citologia , Imuno-Histoquímica , Masculino , Camundongos , Microscopia Eletrônica , Gravidez , Antígeno Nuclear de Célula em Proliferação/metabolismo , Próstata/citologia , Próstata/efeitos dos fármacos , Coelhos , Ratos , Ratos Sprague-Dawley
6.
Endocrinology ; 140(6): 2801-13, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10342871

RESUMO

Exposure of male rats to estrogens during the neonatal period retards prostate branching morphogenesis, blocks epithelial differentiation, and predisposes the adult prostate to hyperplasia and dysplasia. The mechanism of neonatal estrogenization is not well understood. The present study evaluated transforming growth factor-beta (TGFbeta) in the neonatally estrogenized ventral prostate to determine whether this paracrine/autocrine factor may in part mediate the effects ofestrogen on the developing prostate gland. Immunocytochemistry using antibodies against active TGFbeta1 and its latency-associated peptide localized this molecule to the periductal smooth muscle cells in the developing prostate. Although neonatal estrogenization increased the accumulation of total and active TGFbeta1 in the smooth muscle layer as early as day 6 of life, it was physically separated from the epithelial ducts by a proliferating layer of fibroblasts surrounding the basement membrane. RT-PCR demonstrated that alterations in TGFbeta1 levels were not due to alterations in TGFbeta1 transcription. TGFbeta2 and TGFbeta3 were primarily immunolocalized to differentiating epithelial cells in developing prostates, and this was markedly dampened between days 10-30 after neonatal estrogen exposure. Immunocytochemistry for TGFbeta signaling components revealed that neonatal estrogenization transiently reduced TGFbeta type I receptor levels in the prostate epithelium, but not in stroma, between days 6-15, whereas there was no effect on TGFbeta type II receptor. Levels of the intracellular signal Smad2 (52 kDa) were detected in epithelial cells but were not altered after estrogenization. To analyze the functional status of the TGFbeta signaling pathway, immunocytochemistry was performed for p21(cip-1/waf-1), a cyclin-dependent kinase inhibitor that is inducible by TGFbeta1 in the prostate. Transient nuclear localization of p21(cip-1/waf-1) was normally observed in epithelial cells between days 6-15 and was associated with entry of cells into a terminal differentiation pathway. Neonatal estrogenization prevented this transient expression of p21(cip-1/waf-1). The present findings demonstrate that the TGFbeta signaling system is perturbed at several levels in the estrogenized prostate, which may in part account for the epithelial cell differentiation blockade as well as the proliferation of periductal fibroblasts in this model.


Assuntos
Ciclinas/análise , Estrogênios/farmacologia , Próstata/efeitos dos fármacos , Fator de Crescimento Transformador beta/análise , Animais , Animais Recém-Nascidos , Diferenciação Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21 , Proteínas de Ligação a DNA/análise , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/fisiologia , Imuno-Histoquímica , Masculino , Próstata/química , Próstata/citologia , Ratos , Receptores Androgênicos/análise , Receptores de Fatores de Crescimento Transformadores beta/análise , Proteína Smad2 , Transativadores/análise , Fator de Crescimento Transformador beta/imunologia
7.
Endocrinology ; 142(1): 359-69, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11145599

RESUMO

Brief exposure to estrogens during the neonatal period interrupts rat prostatic development by reducing branching morphogenesis and by blocking epithelial cells from entering a normal differentiation pathway. Upon aging, ventral prostates exhibit extensive hyperplasia and dysplasia suggesting that neonatal estrogens may predispose the prostate gland to preneoplastic lesions. To determine whether these prostatic lesions may be manifested through aberrant cell-to-cell communications, the present study examined specific gap junction proteins, Connexins (Cx) 32, and Cx 43, and the cell adhesion molecule, E-cadherin, in the developing, adult and aged rat prostate gland. Male rat pups were given 25 microgram estradiol benzoate or oil on days 1, 3, and 5 of life. Prostates were removed on days 1, 4, 5, 6, 10, 15, 30, or 90 or at 16 months, and frozen sections were immunostained for E-cadherin, Cx 43, and Cx 32. Colocalization studies were performed with immunofluorescence using specific antibodies for cell markers. Gap junctions in undifferentiated epithelial cells at days 1-10 of life were composed of Cx 43, which always colocalized with basal cell cytokeratins (CK 5/15). Cx 32 expression was first observed between days 10-15 and colocalized to differentiated luminal cells (CK 8/18). Cx 43 and Cx 32 never colocalized to the same cell indicating that gap junction intercellular communication differs between basal and luminal prostatic cells. While epithelial connexin expression was not initially altered in the developing prostates following estrogen exposure, adult prostates of neonatally estrogenized rats exhibited a marked decrease in Cx 32 staining and an increased proportion of Cx 43 expressing cells. In the developing prostate, E-cadherin was localized to lateral surfaces of undifferentiated epithelial cells and staining intensity increased as the cells differentiated into luminal cells. By day 30, estrogenized prostates had small foci of epithelial cells that did not immunostain for E-cadherins. In the adult and aged prostates of estrogenized rats, larger foci with differentiation defects and dysplasia were associated with a decrease or loss in E-cadherin staining. The present findings suggest that estrogen-induced changes in the expression of E-cadherin, Cx32 and Cx43 may result in impaired cell-cell adhesion and defective cell-cell communication and may be one of the key mechanisms through which changes toward a dysplastic state are mediated. These findings are significant in light of the data on human prostate cancers where carcinogenesis and progression are associated with loss of E-cadherin and a switch from Cx32 to Cx43 expression in the epithelium.


Assuntos
Envelhecimento/fisiologia , Caderinas/metabolismo , Moléculas de Adesão Celular/metabolismo , Conexinas/metabolismo , Células Epiteliais/fisiologia , Estradiol/farmacologia , Próstata/fisiologia , Animais , Conexina 43/metabolismo , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Humanos , Masculino , Próstata/citologia , Próstata/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Proteína beta-1 de Junções Comunicantes
8.
Medicine (Baltimore) ; 74(3): 136-43, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7760720

RESUMO

To assess the role of circulating immune complexes (CIC) in chronic hepatitis C virus (HCV) infection, the relative frequency of CIC was determined in 60 patients with chronic hepatitis C alone, 19 patients co-infected with hepatitis B and C, 15 asymptomatic HCV carriers, and 54 healthy controls. Levels of CIC were determined with immunoglobulin-specific C1q-binding and conglutinin (K)-binding immune complex assays. Although there was no statistical difference in the levels of each type of CIC between asymptomatic HCV carriers and healthy controls, elevated levels of CIC containing IgM and IgG were common in patients with chronic HCV infection. Compared to patients with hepatitis C alone, patients co-infected with hepatitis B and C have a higher frequency of abnormal IgM-containing CIC and significantly higher levels of IgM-containing CIC. CIC levels in patients with chronic active hepatitis were significantly higher than those in patients with chronic lobular hepatitis or chronic persistent hepatitis. In conclusion, although CIC containing IgM and IgG were common in patients with chronic hepatitis C, abnormal IgM-containing CIC are the major types of CIC in patients co-infected with hepatitis B and C. An immune-mediated mechanism may play a role in the pathogenesis of chronic hepatitis C.


Assuntos
Complexo Antígeno-Anticorpo/análise , Hepatite B/imunologia , Hepatite C/imunologia , Hepatite Crônica/imunologia , Imunoglobulina M/análise , Adulto , Estudos Transversais , Feminino , Hepatite B/complicações , Antígenos de Superfície da Hepatite B/análise , Hepatite C/complicações , Hepatite Crônica/virologia , Humanos , Imunoglobulina G/análise , Masculino
9.
Medicine (Baltimore) ; 76(3): 213-26, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9193456

RESUMO

To assess the clinical relevance of transforming growth factor-beta 1 (TGF-beta 1) in the urine of patients with hepatocellular carcinoma (HCC), TGF-beta 1 was measured, by radioimmunoassay, in 140 patients with HCC, 50 cirrhotic patients, 30 patients with chronic active hepatitis, and 50 healthy controls. The results indicate that there were significantly increased urinary TGF-beta 1 levels in patients with HCC. Raised TGF-beta 1 levels were associated, in a dose-related fashion, with increased risk for development of HCC (odds ratio, 1.05, 95% confidence interval, 1.03-1.07). HCC patients with raised TGF-beta 1 levels had shorter survival than those with normal TGF-beta 1 levels (p = 0.038). TGF-beta 1 levels decreased after successful anticancer therapy (p < 0.0001). There was an inverse correlation between TGF-beta 1 and serum alpha-fetoprotein (AFP) (r = -0.199, p < 0.04). Receiver operating characteristics (ROC) curve analysis indicated that parallel determination of TGF-beta 1 and AFP significantly increased the sensitivity and diagnostic accuracy, with a high specificity. In conclusion, raised urinary TGF-beta 1 was associated with HCC development. It is a predictor of poor prognosis, and a tumor marker for diagnosis and therapeutic follow-up of HCC.


Assuntos
Carcinoma Hepatocelular/urina , Neoplasias Hepáticas/urina , Fator de Crescimento Transformador beta/urina , Adulto , Idoso , Biomarcadores Tumorais , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/fisiopatologia , Progressão da Doença , Feminino , Humanos , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/fisiopatologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Curva ROC , Valores de Referência , Análise de Sobrevida , alfa-Fetoproteínas/análise
10.
Br J Pharmacol ; 116(6): 2637-40, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8590982

RESUMO

1. The effect of L-dopa on the spontaneous and KCl-evoked efflux of dopamine from rat striatal slices, measured by high performance liquid chromatography (h.p.l.c.) with electrochemical detection (e.c.d.) was investigated in the absence and presence of 3-O-methyl dopa (OMD), an O-methylated metabolite of L-dopa. 2. The addition of exogenous L-dopa (10 microM) significantly increased both the spontaneous efflux of dopamine and that evoked by KCl. 3. In the presence of 50 microM OMD, the effects of L-dopa on the spontaneous and KCl-evoked efflux of dopamine were smaller but only the former was significantly different from that in the absence of OMD. However, the total efflux of dopamine during the overall superfusion time (70 min) including KCl depolarization was significantly lower than in the absence of OMD. 4. Analysis of tissue content after superfusion revealed that the levels of dopa and dopamine in slices superfused with L-dopa in the presence of OMD were significantly higher than those superfused with L-dopa alone. 5. The finding that OMD significantly reduced the efflux of dopamine whilst increasing its concentration in striatal slices after L-dopa superfusion could explain the reduced efficacy seen after long-term therapy with L-dopa and a peripheral dopa decarboxylase inhibitor in Parkinsonian patients when plasma and brain OMD are very high.


Assuntos
Antiparkinsonianos/farmacologia , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Dopamina/biossíntese , Dopamina/metabolismo , Levodopa/farmacologia , Tirosina/análogos & derivados , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Líquido Cefalorraquidiano , Interações Medicamentosas , Masculino , Cloreto de Potássio/farmacologia , Ratos , Ratos Sprague-Dawley , Tirosina/farmacologia
11.
Br J Pharmacol ; 121(2): 331-7, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9154345

RESUMO

1. The effects of L-dopa methylester (LDME), an analogue of levodopa, on the spontaneous activity of dopamine sensitive neurones in the rat striatum, after 6-hydroxydopamine induced degeneration of the nigrostriatal tract were compared with those in unlesioned animals both in the absence and presence of benserazide, a peripheral DOPA decarboxylase inhibitor (PDI). 2. Studies were performed at 5-7 days post lesion (group 1 animals), at 21 days (group 2) when denervation supersensitivity was evident by contralateral turning to apomorphine and at the same time but following 7 days dosing with LDME plus benserazide (group 3). 3. In unlesioned animals, LDME alone inhibited spontaneous firing by some 45% over 60 min including a marked but transient early phase which was still present in all lesioned animals even though the later inhibition was significantly reduced in group 1 and 3 animals. 4. When given after benserazide in unlesioned animals LDME still produced a similar level of overall inhibition but without the early phase. The lesion reduced the overall inhibition, except in group 2 animals, and after chronic dosing (group 3) it was almost absent. 5. It is proposed that since the early inhibition with LDME alone is still seen after lesion of the nigrostriatal tract but not after the PDI benserazide, it is caused by peripherally formed dopamine and that as the delayed inhibition with LDME alone and after benserazide are all reduced by nigrostriatal lesions, as is its amphetamine like ipsilateral turning, that this depends on locally (striatal) synthesized dopamine. 6. This study also shows the chronic levodopa/PDI treatment reduces the compensating increased activity of surviving dopaminergic neurones and the functional supersensitivity to dopamine and suggests that the long term administration of levodopa may reduce its own utilization and activity in the striatum and in the treatment of Parkinson's Disease [corrected].


Assuntos
Benserazida/farmacologia , Levodopa/farmacologia , Córtex Visual/efeitos dos fármacos , Animais , Interações Medicamentosas , Masculino , Oxidopamina/farmacologia , Ratos , Ratos Sprague-Dawley
12.
Cancer Lett ; 107(1): 37-44, 1996 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-8913264

RESUMO

Gossypol (GP), an antifertility agent in males, is also capable of inhibiting the proliferation of a wide range of cancer cells in vivo and in vitro. Thus, in this study we investigated the effect of GP on the growth of human androgen-independent prostate cancer cell line (PC3). The results showed that GP acts as a potent inhibitor of PC3 cells as determined by thymidine incorporation assay and flow cytometric analysis. Flow cytometry revealed that treatment of PC3 cells with GP resulted in a dose- and time-dependent accumulation of cells in the GO/GI phase with a concomitant decrease in cells progressing to the S and G2/M phase. These data support our thymidine incorporation results which indicated that GP is a potent inhibitor of PC3 cells. By ribonuclease protection assay, we also investigated the effect of GP on transforming growth factor-beta 1 (TGF-beta 1) gene expression in PC3 cells. Interestingly, the stimulatory effect of GP on TGF-beta 1 gene expression correlates well with its inhibitory effect on PC3 cell DNA synthesis and its ability to arrest cells in GO/G1 phase. Based on these data, it can be concluded that GP is a potent inhibitor of prostate cancer cell growth that acts by arresting cells in GO/G1 phase and that this inhibitory effect may be mediated by TGF-beta 1.


Assuntos
Divisão Celular/efeitos dos fármacos , Gossipol/farmacologia , Neoplasias da Próstata/patologia , Fator de Crescimento Transformador beta/biossíntese , Ciclo Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Masculino , Neoplasias da Próstata/metabolismo , RNA Mensageiro/biossíntese , Células Tumorais Cultivadas
13.
Eur J Endocrinol ; 142(5): 431-7, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10802518

RESUMO

OBJECTIVE: Hepatitis C virus (HCV), being reported to be associated with a high prevalence of serological markers of autoimmunity in HCV-infected patients, and possibly sharing partial sequences in amino acid segments with thyroid tissue antigens, may be associated with interferon-alpha (IFN-alpha)-induced thyroid dysfunction in chronic hepatitis C patients. We conducted this study to clarify the issue. DESIGN AND METHODS: One hundred and fifty chronic hepatitis C patients with normal baseline thyroid function were treated with IFN-alpha 2a, 2b and n1 (3-6 million Units three times weekly for 24 weeks). Pretreatment sera were tested for HCV genotype and HCV RNA levels. Serum thyrotropin, total thyroxine and free thyroxine index were performed every 4 weeks for 24 weeks followed by every 8 weeks for another 24 weeks. RESULTS: Twenty-one (14.0%) patients developed early thyroid dysfunction (abnormal thyroid function during the first 3 months of therapy). Female gender, lower HCV RNA levels, IFN-alpha n1 and a lower IFN-alpha dose were significantly associated with early thyroid dysfunction. On multivariate analysis, gender, IFN-alpha preparation and HCV RNA levels were the significant factors associated with early thyroid dysfunction. Seven (4.7%) patients developed thyroid dysfunction during the second 3 months of IFN-alpha therapy. Taken together, 18.7% patients developed thyroid dysfunction. Female, mixed HCV genotype infection and lower HCV RNA levels were significantly associated with thyroid dysfunction. However, only gender remained significantly associated with IFN-alpha-induced thyroid dysfunction in multivariate analysis. CONCLUSIONS: The virologic features of HCV may be associated with thyroid dysfunction in chronic hepatitis C patients treated with IFN-alpha. Nevertheless, gender still plays the most important role in IFN-alpha-induced thyroid dysfunction.


Assuntos
Antivirais/efeitos adversos , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/efeitos adversos , Doenças da Glândula Tireoide/induzido quimicamente , Doenças da Glândula Tireoide/virologia , Hormônios Tireóideos/sangue , Adolescente , Adulto , Idoso , Antivirais/uso terapêutico , Ensaios Clínicos como Assunto , Feminino , Hepacivirus/genética , Hepatite C Crônica/sangue , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , RNA Viral/sangue , Proteínas Recombinantes , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Fatores Sexuais , Doenças da Glândula Tireoide/sangue , Testes de Função Tireóidea
14.
Pediatr Infect Dis J ; 17(2): 142-5, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9493811

RESUMO

BACKGROUND: According to our previous studies, Paisha Township in Penghu Islets is an endemic area for hepatitis B virus and hepatitis C virus (HCV) infection and for hepatocellular carcinoma. We conducted this study to understand the prevalence of anti-HCV seropositivity among children in this area and to observe clinical manifestations of anti-HCV-positive children. METHODS: In March, 1994, 1164 (93.6%) of 1243 students from all 6 kindergartens, 9 primary schools and 3 middle schools in Paisha Township participated in the screening for anti-HCV by enzyme immunoassay with second generation commercial kits (Abbott EIA 2.0). Anti-HCV tests were duplicated for the positive sera in 2 laboratories. All anti-HCV-positive children were followed annually for 2 years. RESULTS: The prevalences of children from kindergartens (ages 3 to 6 years), primary schools (ages 7 to 12 years) and middle schools (ages 13 to 15 years) were 0% (0 of 229), 0.8% (5 of 617) and 1.9% (6 of 318), respectively. Initially the optic density (OD) values of anti-HCV were > 2.0 in 4 cases (36%), between 1.0 and 2.0 in 2 cases, and < 1.0 in the other 5 cases. None had sonographic parenchymal changes in the liver. In the 2-year follow-up of the anti-HCV-positive subjects, type 2a HCV-RNA persisted in 3 of 4 children with an OD of anti-HCV more than 2.0; 2 of them had 2 elevations of alanine transaminase values. Four of 7 children with an OD of 2.0 or less had a decrease in OD values in the follow-up examinations, and 2 of them became anti-HCV-negative. CONCLUSION: Only 36% (4 of 11) of anti-HCV-positive children had an OD of > 2.0. Subjects with sequentially low OD might recover from chronic HCV infection without detectable HCV RNA and with normal alanine aminotransferase values.


Assuntos
Hepacivirus/isolamento & purificação , Hepatite C/epidemiologia , Adolescente , Criança , Pré-Escolar , Antígenos de Superfície da Hepatite B/análise , Hepatite C/imunologia , Antígenos da Hepatite C/análise , Humanos , Prevalência , RNA Viral/análise , Fatores de Risco , Estudos Soroepidemiológicos , Taiwan/epidemiologia
15.
Antiviral Res ; 52(3): 241-9, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11675141

RESUMO

GB virus C/hepatitis G virus (GBV-C/HGV) RNA, detected by polymerase chain reaction, and antibodies to the GBV-C/HGV envelope protein (anti-E2), detected by an enzyme-linked immunosorbent assay, were used to evaluate both the impact of GBV-C/HGV on the coexistent hepatitis C virus (HCV) infection and the course of GBV-C/HGV infection in chronic hepatitis C patients with and without interferon-alpha (IFN-alpha) treatment. Of the 162 chronic hepatitis C patients treated with INF-alpha, 17.9% were GBV-C/HGV RNA-positive and 18.5% anti-E2-positive (total exposure, 35.2%). Neither present nor past GBV-C/HGV infection had impact on the clinical features, HCV virological characteristics and response to IFN-alpha treatment in chronic hepatitis C patients. Among patients with ongoing HCV/GBV-C/HGV coinfection, 20.7% (6/29) in IFN-alpha-treated patients lost GBV-C/HGV RNA concomitant with anti-E2 seropositivity, which was significantly higher than 4.8% (2/42) in patients without INF-alpha treatment (P<0.05). Based on multivariate analyses, the significant factors associated with clearance of GBV-C/HGV viremia combined with anti-E2 seropositivity were baseline anti-E2 seropositivity and IFN-alpha treatment. In summary, GBV-C/HGV did not alter the course of coexistent HCV. IFN-alpha treatment was effective in some patients against GBV-C/HGV and might facilitate anti-E2 seroconversion in chronic hepatitis C patients with GBV-C/HGV viremia.


Assuntos
Infecções por Flaviviridae/tratamento farmacológico , Vírus GB C/fisiologia , Hepatite C Crônica/tratamento farmacológico , Hepatite Viral Humana/tratamento farmacológico , Hepatite Viral Humana/virologia , Interferon-alfa/uso terapêutico , Adolescente , Adulto , Idoso , Ensaio de Imunoadsorção Enzimática , Feminino , Infecções por Flaviviridae/complicações , Infecções por Flaviviridae/imunologia , Infecções por Flaviviridae/virologia , Vírus GB C/efeitos dos fármacos , Vírus GB C/imunologia , Anticorpos Anti-Hepatite/análise , Anticorpos Anti-Hepatite/imunologia , Hepatite C Crônica/complicações , Hepatite C Crônica/imunologia , Hepatite C Crônica/virologia , Hepatite Viral Humana/complicações , Hepatite Viral Humana/imunologia , Humanos , Interferon-alfa/farmacologia , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Estudos Retrospectivos , Taiwan , Viremia/tratamento farmacológico , Viremia/imunologia , Viremia/virologia
16.
Int J Epidemiol ; 26(1): 24-31, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9126500

RESUMO

BACKGROUND: Although cigarette smoking is considered to be the most important cause of lung cancer, smoking behaviour cannot fully explain the epidemiological characteristics of lung cancer in Taiwanese women, who rarely smoke but contract lung cancer relatively often. There are other causes of lung cancer that have produced variability in lung cancer incidence. METHODS: A case-control study involving interviews with 117 female patients (including 106 non-smoking) suffering from lung cancer and the same number of individually matched hospital controls was conducted in Kaohsiung, Taiwan between 1992 and 1993. The questionnaire administered to cases and controls collected information on cigarette smoking and suspected risk factors for lung cancer. Multivariate logistic regression analysis was applied to assess smoking for all women and suspected risk factors for non-smoking women. RESULTS: The relationship between cigarette smoking and lung cancer was statistically significant although only a small proportion (9.4%) of female patients had smoked. However, the risk of contracting cancer for non-smoking women appears to be associated with certain cooking practices, especially preparing meals in kitchens not equipped with a fume extractor at cooking age of 20-40 years (odds ratio [OR] = 8.3; 95% confidence interval [CI]: 3.1-22.7. These factors and a history of pulmonary tuberculosis plus low consumption of fresh vegetables explained 78% of the summary attributable risks for non-smoking women in a multivariate logistic regression model. CONCLUSIONS: Exposure to fumes from cooking oils, when not reduced by an extractor, may be an important factor in causing lung cancer in non-smoking Taiwanese women.


Assuntos
Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/etiologia , Poluição por Fumaça de Tabaco/efeitos adversos , Adulto , Distribuição por Idade , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Incidência , Modelos Logísticos , Neoplasias Pulmonares/diagnóstico , Pessoa de Meia-Idade , Análise Multivariada , Fatores de Risco , Taxa de Sobrevida , Taiwan/epidemiologia
17.
DNA Cell Biol ; 15(3): 247-54, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8634153

RESUMO

cDNA encoding the canine keratinocyte growth factor (KGF) was cloned from normal canine prostate tissue. The authentic canine KGF cDNA sequence, 686 bp in length, spans the protein-coding region and 88 bp of the 5' and 19 bp of the 3' untranslated regions of canine KGF. The predicted amino acid sequence of canine KGF is composed of 194 amino acid residues. Canine KGF exhibits highest homology with the human KGF cDNA and amino acid sequences (95.8% and 97.4%, respectively), while it demonstrates the lowest homology with the rat sequences at 88.0% and 92.3%, respectively. The degrees of homology with mouse cDNA and amino acid sequences are 91.8% and 95.9%, respectively. By using RNase protection assay, KGF was shown to be expressed in normal prostate tissues of both mature and young (5-month-old) dogs. In vitro, the recombinant canine KGF has mitogenic activity on cultured canine epithelial cells, whereas it has no effect on cultured canine prostatic stromal cells. This novel canine KGF cDNA may be a valuable tool in the study of human benign prostatic hyperplasia using the canine prostatic as a model.


Assuntos
Fatores de Crescimento de Fibroblastos , Substâncias de Crescimento/fisiologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Células Cultivadas , Clonagem Molecular , Primers do DNA/química , DNA Complementar/genética , Cães , Células Epiteliais , Fator 10 de Crescimento de Fibroblastos , Fator 7 de Crescimento de Fibroblastos , Expressão Gênica , Humanos , Masculino , Dados de Sequência Molecular , Próstata/fisiologia , Alinhamento de Sequência
18.
J Clin Pathol ; 52(11): 807-11, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10690168

RESUMO

AIM: To compare the performance characteristics and clinical application of two different technologies for quantifying serum hepatitis C virus (HCV) RNA levels. METHODS: HCV RNA was quantified by Amplicor HCV Monitor assay (Amplicor) and Quantiplex HCV RNA 2.0 assay (bDNA-2) in 119 sera from 107 HCV infected patients. RESULTS: Both assays had similar sensitivity (79.4% for Amplicor; 86.0% for bDNA-2), acceptable coefficients of variation (5.3% in Amplicor; 2.6% in bDNA-2), and good linearity (r2 > or = 0.98). There was a positive correlation between quantification values of both methods (r = 0.683, p < 0.001). The Amplicor values were on an average 1.76 log lower than bDNA-2 results. Male subjects and HCV genotype 1b were significantly associated with higher viral load determined by Amplicor, but not with viral load measured by bDNA-2. In 70 chronic HCV infected patients treated with interferon alfa, mean (SD) pretreatment viral load in 27 complete responders (3.47 (0.84) logs for Amplicor, 5.63 (0.58) for bDNA-2) was significantly lower than in non-responders (4.43 (1.01) logs for Amplicor, 6.10 (0.67) logs for bDNA-2; p < 0.001). Cut off points of 3.9 logs for Amplicor and 5.8 logs for bDNA-2 were determined to be the best for predicting response to interferon alfa, giving acceptable sensitivity (70.4%, 74.1%), specificity (72.1%, 65.1%), and accuracy (71.4%, 68.6%), respectively. CONCLUSIONS: Both the Amplicor and bDNA-2 assays are clinically useful methods for HCV RNA quantification and are reliable for predicting the outcome of treatment, despite differences in absolute quantification values and in the correlation between HCV genotypes and viral load.


Assuntos
Hepacivirus/genética , Hepatite C Crônica/diagnóstico , RNA Viral/sangue , Kit de Reagentes para Diagnóstico , Adulto , Feminino , Genótipo , Hepatite C Crônica/tratamento farmacológico , Humanos , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade , Fatores Sexuais , Resultado do Tratamento , Carga Viral
19.
J Clin Pathol ; 57(2): 141-5, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14747437

RESUMO

AIMS: To evaluate the performance characteristics and clinical usefulness of the COBAS Amplicor HBV monitor (COBAS-AM) test in Taiwan and to examine its correlation with the Quantiplex branched DNA signal amplification (bDNA) assay for measuring serum hepatitis B virus (HBV) DNA concentrations. METHODS: HBV DNA was measured by the COBAS-AM test in 149 sera from chronic HBV infected patients that had previously been analysed by the bDNA assay. RESULTS: The COBAS-AM test showed good reproducibility, with acceptable intra-assay and interassay coefficients of variation (1.6% and 0.9%, respectively) and good linearity (r2=0.98). The overall sensitivity of the COBAS-AM test was significantly higher than that of the bDNA assay (95.3% v 83.2%): 69.6% of samples with HBV DNA below the detection limit of the bDNA assay could be measured by the COBAS-AM test. There was a significant correlation between the results of the two assays (r=0.901; p<0.0001). On average, the results derived from the COBAS-AM test were 0.55 log lower than those of the bDNA assay. HBV DNA concentrations were significantly higher among HBV e antigen (HBeAg) positive patients than negative ones, and higher among patients with abnormal alanine aminotransferase (ALT) concentrations than those with normal ALT concentrations (p=0.0003). CONCLUSIONS: The COBAS-AM assay, more sensitive in HBeAg negative samples than the bDNA assay, can effectively measure HBV DNA concentrations in Taiwanese patients. HBV DNA values measured by the COBAS-AM test and bDNA assay correlate significantly.


Assuntos
DNA Viral/sangue , Vírus da Hepatite B/genética , Hepatite B Crônica/diagnóstico , Adolescente , Adulto , Ensaio de Amplificação de Sinal de DNA Ramificado , Feminino , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Carga Viral
20.
J Mass Spectrom ; 36(8): 882-8, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11523087

RESUMO

Since retinoic acid (RA) and RA receptors are key developmental regulators during organogenesis, they might participate in the abnormal development of the prostate caused by early estrogen exposure. In order to test this assumption, a sensitive analytical method that can differentiate 9-cis, 13-cis, and all-trans RA in small tissue samples ( approximately 8 mg) is required. Since retinol is the metabolic precursor to RA, simultaneous quantification of retinol would also provide valuable information. Here, we report a liquid chromatography-mass spectrometry method for simultaneous determination of retinol and 9-cis, 13-cis, and all-trans RA in rat prostate. Mass spectrometric signal responses for RA were compared using positive ion atmospheric-pressure chemical ionization (APCI) and electrospray, as well as positive ion and negative ion APCI. Positive ion APCI was selected for all subsequent analysis for its better sensitivity, and to provide simultaneous determination of retinol and RA. Ventral prostate tissue samples were homogenized and extracted following simple protein precipitation without derivatization. Baseline separation of 9-cis, 13-cis, and all-trans RA standards was obtained by using a non-porous silica C18 column. Selected ion monitoring of the ions m/z 301 and m/z 269 was carried out for mass spectrometric quantitative analysis. The ion of m/z 301 corresponded to the protonated molecule of RA, whereas the ion of m/z 269 corresponded to loss of water or acetic acid from the protonated molecule of retinol or the internal standard retinyl acetate respectively. The method has a linear response over a concentration range of at least three orders of magnitude. The limit of quantitation was determined to be 702 fmol all-trans RA injected on-column. The method showed excellent intra- and inter-assay reproducibility and good recovery, and is suitable for analyzing RA and retinol in small tissue samples (approximately 8 mg).


Assuntos
Isotretinoína/análise , Próstata/química , Tretinoína/análise , Vitamina A/análise , Alitretinoína , Animais , Cromatografia Líquida/métodos , Isotretinoína/química , Masculino , Espectrometria de Massas/métodos , Ratos , Tretinoína/química , Vitamina A/química
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