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1.
Oncogene ; 36(16): 2228-2242, 2017 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-27797381

RESUMO

Epidermal growth factor (EGF) is important for cancer cell proliferation, angiogenesis and metastasis in many types of cancer. However, the mechanisms involved in EGF-induced head and neck squamous cell carcinoma (HNSCC) metastasis remain largely unknown. In this study, we reveal that angiopoietin-like 4 (ANGPTL4) plays an important role in the regulation of EGF-induced cancer metastasis. We showed that EGF-induced ANGPTL4 expression promoted anoikis resistance and cancer cell migration and invasion in HNSCC. In addition, depletion of ANGPTL4 inhibited EGF-induced cancer cell invasion. Autocrine production of EGF-induced ANGPTL4 regulated the expression of matrix metalloproteinases (MMPs). The induction of MMP-1 gene expression by ANGPTL4-activated integrin ß1 signalling occurred through the AP-1 binding site in the MMP-1 gene promoter. Furthermore, down-regulation of MMP-1 impeded EGF- and recombinant ANGPTL4-enhanced HNSCC cell migration and invasion. Depletion of ANGPTL4 significantly blocked EGF-primed extravasation and metastatic seeding of tumour cells and MMP-1 expression in lungs. However, no effect of ANGPTL4 on tumour growth was observed. These results suggest that EGF-induced expression and autocrine production of ANGPTL4 enhances HNSCC metastasis via the up-regulation of MMP-1 expression. Inhibition of ANGPTL4 expression may be a potential strategy for the treatment of EGFR-mediated HNSCC metastasis.


Assuntos
Angiopoietinas/metabolismo , Anoikis , Carcinoma de Células Escamosas/metabolismo , Fator de Crescimento Epidérmico/fisiologia , Neoplasias de Cabeça e Pescoço/metabolismo , Proteína 4 Semelhante a Angiopoietina , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/secundário , Linhagem Celular Tumoral , Genes jun , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/secundário , Humanos , Integrina beta1/metabolismo , Metaloproteinase 1 da Matriz/biossíntese , Metástase Neoplásica , Transdução de Sinais , Carcinoma de Células Escamosas de Cabeça e Pescoço
2.
Ultrason Sonochem ; 27: 456-465, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26186867

RESUMO

An integrated computational framework was developed in this study for modeling high-intensity focused ultrasound (HIFU) thermal ablation. The temperature field was obtained by solving the bioheat transfer equation (BHTE) through the finite element method; while, the thermal lesion was considered as a denatured material experiencing phase transformation and modeled with the latent heat. An equivalent attenuation coefficient, which considers the temperature-dependent properties of the target material and the ultrasound diffraction due to bubbles, was proposed in the nonlinear thermal transient analysis. Finally, a modified thermal dose formulation was proposed to predict the lesion size, shape and location. In-vitro thermal ablation experiments on transparent tissue phantoms at different energy levels were carried out to validate this computational framework. The temperature histories and lesion areas from the proposed model show good correlation with those from the in-vitro experiments.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade , Modelos Biológicos , Temperatura , Análise de Elementos Finitos , Hidrogéis , Imagens de Fantasmas , Software
4.
Int J Tuberc Lung Dis ; 17(7): 928-33, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23743312

RESUMO

OBJECTIVE: To investigate whether or not there is an increased risk of pulmonary tuberculosis (PTB) after non-tuberculous mycobacterial (NTM) disease. DESIGN: A retrospective cohort study of 212 NTM patients and 4240 control cases. RESULTS: Patients with previous NTM disease had a significantly higher incidence of PTB than controls (incidence rate ratio [IRR] 14.74, 95%CI 8.71-24.94, P < 0.0001). Cox's proportional hazards analysis yielded an adjusted hazards ratio (aHR) of 10.15 (95%CI 5.67-18.17, P < 0.05) for NTM-associated PTB. The majority of the PTB cases (17/23, 73.9%) were diagnosed within 6 months after the diagnosis of NTM disease. Older age (≥65 years, aHR 4.45, 95%CI 1.94-10.22, P < 0.05), male sex (aHR 1.75, 95%CI 1.01-3.13, P < 0.05), human immunodeficiency virus (HIV) infection (aHR 12.49, 95%CI 3.20-48.79, P < 0.05) and chronic obstructive pulmonary disease (aHR 4.46, 95%CI 2.19-9.10, P < 0.05) were independent risk factors for developing PTB after NTM disease. The cumulative incidence of PTB in patients with previous NTM disease was significantly higher than in controls (P < 0.0001, Kaplan-Meier analysis). However, there was no significant difference in the survival rates in the two cohorts. CONCLUSION: Increased PTB prevalence after NTM disease was demonstrated. HIV infection was the greatest independent risk factor for subsequent development of PTB.


Assuntos
Infecções por HIV/epidemiologia , Infecções por Mycobacterium não Tuberculosas/epidemiologia , Tuberculose Pulmonar/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Seguimentos , Infecções por HIV/complicações , Humanos , Incidência , Lactente , Masculino , Pessoa de Meia-Idade , Infecções por Mycobacterium não Tuberculosas/complicações , Prevalência , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Taxa de Sobrevida , Fatores de Tempo , Tuberculose Pulmonar/etiologia , Adulto Jovem
5.
Mol Syndromol ; 4(3): 114-8, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23653582

RESUMO

Segmental hemangiomas of the head and neck can be associated with multiple congenital anomalies in the disorder known as PHACE syndrome (OMIM 606519) (posterior fossa malformations, hemangioma, arterial anomalies, cardiac defects, and eye anomalies). All reported cases of PHACE syndrome to date have been sporadic, and the genetic basis of this disorder has not yet been established. PHACE syndrome has a striking female predominance which has raised the question of X-linked inheritance. In this study, the X chromosome-inactivation (XCI) patterns of 31 females with PHACE syndrome and their mothers were analyzed using blood-derived DNA and X-chromosome locus methylation assay. This study was performed to test the hypothesis that some cases of PHACE syndrome are due to X-linked inheritance and favorable skewing in the mothers may protect against a severe phenotype, but the clinical phenotype may be unmasked in daughters with a random pattern of X-inactivation. XCI analysis was informative in 27/31 mothers. Our results identified skewed XCI in 5 of 27 (19%) informative mothers, which is not statistically significant with a p value of 0.41. None of the mothers reported significant medical problems, although a full PHACE work-up has not been performed in these individuals. Skewed XCI in the mothers of children with PHACE was identified in only a minority of cases. Based on these results, genetic heterogeneity is likely in PHACE syndrome, although it is possible a subset of cases are caused by a mutation in an X-linked gene.

6.
J Nutr Health Aging ; 15(5): 341-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21528159

RESUMO

OBJECTIVES: To predict the nutrition and health status of staff and students in Yuan Ze University and select the influential variables from the total body composition variables, which should have similar predictive ability with the whole factors. DESIGN: Spontaneous and voluntary physical examination. SETTING: Sanitary and Health Care Section of Yuan Ze University in Taiwan. PARTICIPANTS: 1227 staff and students. MEASUREMENTS: With the help of Inbody720TM, 139 body composition variables were measured and 60 variables were retained after data pre-processing. An ensembled artificial neural networks (EANN) prediction model was established and seven different methods for assessing variables importance were applied. Besides, classical linear and logistic regression models were developed for comparison with EANN prediction results. RESULTS: The prediction performance of EANN model was satisfactory (RMSE (train) = 0.2686, RMSE (validation) = 0.2648, RMSE (test) = 0.3492). Since both the actual and simulation fitness score were at the range of 0 to 100, according to rounding off rule, the simulated value was almost the same with actual value. Besides, 12 important variables were obtained by seven methods for quantifying variable importance in EANN, which had similar predictive capability with 60 variables (RMSE (train) = 0.3263, RMSE (validation) = 0.322, RMSE (test) = 0.3226). The linear and logistic regression models results were both evidently worse than EANN results. CONCLUSION: The results confirm that EANN is appropriate to approximate such a complicated, non-invasive and highly non-linear problem as body composition analysis. It can be helpful for nutritionists to manage and improve the nutrition and health condition of staff and students, by adjusting the 12 most important variables.


Assuntos
Antropometria/métodos , Composição Corporal , Nível de Saúde , Redes Neurais de Computação , Aptidão Física , Adolescente , Adulto , Idoso , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Exame Físico , Reprodutibilidade dos Testes , Adulto Jovem
7.
Transplant Proc ; 42(7): 2590-3, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20832550

RESUMO

OBJECTIVE: To test in a prospective randomized study the hypothesis that use of thromboelastography (TEG) decreases blood transfusion during major surgery. MATERIAL AND METHODS: Twenty-eight patients undergoing orthotopic liver transplantation were recruited over 2 years. Patients were randomized into 2 groups: those monitored during surgery using point-of-care TEG analysis, and those monitored using standard laboratory measures of blood coagulation. Specific trigger points for transfusion were established in each group. RESULTS: In patients monitored via TEG, significantly less fresh-frozen plasma was used (mean [SD], 12.8 [7.0] units vs 21.5 [12.7] units). There was a trend toward less blood loss in the TEG-monitored patients; however, the difference was not significant. There were no differences in total fluid administration and 3-year survival. CONCLUSION: Thromboelastography-guided transfusion decreases transfusion of fresh- frozen plasma in patients undergoing orthotopic liver transplantation, but does not affect 3-year survival.


Assuntos
Transplante de Fígado/métodos , Transplante de Fígado/fisiologia , Tromboelastografia/métodos , Adulto , Coagulação Sanguínea , Perda Sanguínea Cirúrgica , Transfusão de Sangue/métodos , Feminino , Hematócrito , Humanos , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória/métodos , Monitorização Fisiológica/métodos , Tempo de Tromboplastina Parcial , Estudos Prospectivos
8.
Br J Dermatol ; 163(2): 310-20, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20426785

RESUMO

BACKGROUND: Imiquimod shows antitumour activity through the stimulation of cell-mediated immunity in vivo. Recent studies have shown that imiquimod promotes apoptosis in melanoma cells and induces autophagy in macrophage cell lines. OBJECTIVES: To evaluate the imiquimod-induced apoptosis, autophagy and their relationship in a basal cell carcinoma (BCC) cell line. METHODS: Cell viability was determined by XTT test. Apoptosis was evaluated by DNA content assay, annexin V/propidium iodide staining assay and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labelling assay. Autophagy was determined by LC3 immunoblotting, EGFP-LC3 puncta formation and quantification of acidic vesicular organelles with acridine orange staining. The temporal and spatial differences of imiquimod-induced apoptosis and autophagy were examined by immunoblotting and simultaneously monitored by staining the EGFP-LC3 transfected cells with caspase 3 fluorogenic substrate. We inhibited the apoptosis and autophagy by pancaspase inhibitor and siRNA for Beclin 1 or Atg5, respectively, to evaluate the interplay between imiquimod-induced apoptosis and autophagy. RESULTS: We found that imiquimod induces autophagy and apoptosis in BCC cells in a time- and dose-dependent manner. Imiquimod not only induced EGFP-LC3 puncta formation for autophagy, but also simultaneously activated an apoptotic caspase cascade in the same cells. Both apoptosis and autophagy induced by imiquimod cooperate to cause BCC cell death. However, inhibition of imiquimod-induced apoptosis increased the strength of autophagy, and inhibition of imiquimod-induced autophagy further promoted cell apoptosis. CONCLUSIONS: This study not only demonstrates that imiquimod can directly induce autophagy and apoptosis in BCC cells, but also shows the cooperation and coordination between these two processes to induce cell death.


Assuntos
Aminoquinolinas/farmacologia , Antineoplásicos/farmacologia , Apoptose , Autofagia , Carcinoma Basocelular/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Carcinoma Basocelular/patologia , Inibidores de Caspase , Caspases/metabolismo , Linhagem Celular Tumoral/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Imiquimode , Neoplasias Cutâneas/patologia , Células Tumorais Cultivadas
9.
Hum Mutat ; 29(2): 330-1, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18205204

RESUMO

Published mutations in deoxyguanosine kinase (DGUOK) cause mitochondrial DNA depletion and a clinical phenotype that consists of neonatal liver failure, nystagmus and hypotonia. In this series, we have identified 15 different mutations in the DGUOK gene from 9 kindreds. Among them, 12 have not previously been reported. Nonsense, splice site, or frame-shift mutations that produce truncated proteins predominate over missense mutations. All patients who harbor null mutations had early onset liver failure and significant neurological disease. These patients have all died before 2-years of age. Conversely, two patients carrying missense mutations had isolated liver disease and are alive in their 4th year of life without liver transplant. Five subjects were detected by newborn screening, with elevated tyrosine or phenylalanine. Consequently, this disease should be considered if elevated tyrosine is identified by newborn screening. Mitochondrial DNA content was below 10% of controls in liver in all but one case and modestly reduced in blood cells. With this paper a total of 39 different mutations in DGUOK have been identified. The most frequent mutation, c.763_c.766dupGATT, occurs in 8 unrelated kindreds. 70% of mutations occur in only one kindred, suggesting full sequencing of this gene is required for diagnosis. The presentation of one case with apparent viral hepatitis, without neurological disease, suggests that this disease should be considered in patients with infantile liver failure regardless of the presence of neurological features or apparent infectious etiology.


Assuntos
DNA Mitocondrial/genética , Mutação/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Adolescente , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Especificidade de Órgãos
10.
J Biomol Tech ; 19(4): 267-74, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19137117

RESUMO

G protein-coupled receptors (GPCRs) are involved in various physiological processes, such as behavior changes, mood alteration, and regulation of immune-system activity. Thus, GPCRs are popular targets in drug screening, and a well-designed assay can speed up the discovery of novel drug candidates. The Promega cAMP-Glo Assay is a homogenous bioluminescent assay to monitor changes in intracellular cyclic adenosine monophosphate (cAMP) concentrations in response to the effect of an agonist, antagonist, or test compound on GPCRs. Together with the Labcyte Echo 555 acoustic liquid handler and the Deerac Fluidics Equator HTS reagent dispenser, this setup can screen compounds in 96-, 384-, and 1536-well formats for their effects on GPCRs. Here, we describe our optimization of the cAMP-Glo assay in 1536-well format, validate the pharmacology, and assess the assay robustness for HTS. We have successfully demonstrated the use of the assay in primary screening applications of known agonist and antagonist compounds, and confirmed the primary hits via secondary screening. Implementing a high-throughput miniaturized GPCR assay as demonstrated here allows effective screening for potential drug candidates.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Biotecnologia , AMP Cíclico/metabolismo , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos/instrumentação , Humanos , Técnicas In Vitro , Medições Luminescentes/métodos , Miniaturização , Transdução de Sinais/efeitos dos fármacos
11.
Acta Anaesthesiol Scand ; 52(2): 280-4, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17999708

RESUMO

BACKGROUND: We evaluated the prophylactic effect of low-dose haloperidol (1 mg) on post-operative nausea and vomiting (PONV) in women undergoing ambulatory laparoscopic surgery. Droperidol (0.625 mg) and saline were controls. METHODS: One hundred and fifty women undergoing ambulatory laparoscopic surgery under general anaesthesia were enrolled in this randomized, double-blind, and placebo-controlled study. After tracheal intubation, the haloperidol group (n=50) received intravenous haloperidol (1 mg), the droperidol group (n=50) received intravenous droperidol (0.625 mg), and the saline group (n=50) received intravenous saline. RESULTS: Haloperidol- and droperidol-group patients reported a lower incidence of PONV [24% and 23% vs. 49% (saline group); P<0.05] and requested fewer doses of rescue antiemetics [13% and 16% vs. 38% (saline group); P<0.05] during the first four post-operative hours. During the 24-h post-operative period, haloperidol- and droperidol-group patients also reported a lower incidence of PONV [31% and 32% vs. 62% (saline group); P<0.01]. No differences were found between the haloperidol and droperidol groups. CONCLUSION: Like droperidol (0.625 mg), prophylactic intravenous haloperidol (1 mg) significantly reduced the incidence of PONV in women undergoing ambulatory laparoscopic surgery.


Assuntos
Procedimentos Cirúrgicos Ambulatórios , Anestesia Geral/efeitos adversos , Antieméticos/uso terapêutico , Haloperidol/uso terapêutico , Laparoscopia , Náusea e Vômito Pós-Operatórios/prevenção & controle , Adulto , Anestésicos Inalatórios/administração & dosagem , Anestésicos Inalatórios/efeitos adversos , Anestésicos Intravenosos/administração & dosagem , Anestésicos Intravenosos/efeitos adversos , Antieméticos/administração & dosagem , Desflurano , Relação Dose-Resposta a Droga , Método Duplo-Cego , Droperidol/administração & dosagem , Eletrocardiografia , Feminino , Fentanila/administração & dosagem , Fentanila/efeitos adversos , Humanos , Isoflurano/administração & dosagem , Isoflurano/efeitos adversos , Isoflurano/análogos & derivados , Cloreto de Sódio/administração & dosagem , Resultado do Tratamento
12.
Ann N Y Acad Sci ; 1106: 114-42, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17442773

RESUMO

Nucleoporin 98 (NUP98) is a component of the nuclear pore complex that facilitates mRNA export from the nucleus. It is mapped to 11p15.5 and is fused to a number of distinct partners, including nine members of the homeobox family as a consequence of leukemia-associated chromosomal translocations. NUP98-HOXA9 is associated with the t(7;11)(p15;p15) translocation in acute myeloid leukemia (AML), myelodysplastic syndrome, and blastic crisis of chronic myeloid leukemia. Expression of NUP98-HOXA9 in murine bone marrow resulted in a myeloproliferative disease progressing to AML by 7-8 months. Transduction of NUP98 fusion genes into human CD34(+) cells confers a proliferative advantage in long-term cytokine-stimulated and stromal cocultures and in NOD-SCID engrafted mice, associated with a five- to eight-fold increase in hematopoietic stem cells. NUP98-HOXA9 expression inhibited erythroid and myeloid differentiation but enhanced serial progenitor replating. NUP98-HOXA9 upregulated a number of homeobox genes of the A and B cluster as well as MEIS1 and Pim-1, and downmodulated globin genes and C/EBPalpha. The HOXA9 component of the NUP98-HOXA9 fusion protein was protected from cullin-4A-mediated ubiquitination and subsequent proteasome-dependent degradation. In NUP98-HOX-transduced CD34(+) cells and cells from AML patients with t(7;11)(p15;p15) NUP98 was no longer associated with the nuclear pore complex but formed intranuclear aggregation bodies. Analysis of NUP98 allelic expression in AML and myelodysplastic syndrome showed loss of heterozygosity observed in 29% of the former and 8% of the latter. This was associated with poor prognosis.


Assuntos
Regulação Neoplásica da Expressão Gênica , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/fisiologia , Alelos , Animais , Antígenos CD34/biossíntese , Núcleo Celular/metabolismo , Cromossomos Humanos Par 11 , Cromossomos Humanos Par 7 , Humanos , Perda de Heterozigosidade , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/metabolismo
13.
Comb Chem High Throughput Screen ; 8(6): 489-98, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16178808

RESUMO

Compounds used in high throughput screening (HTS) are typically dissolved in DMSO. These solutions are stored automation-friendly racks of wells or tubes. DMSO is hygroscopic and quickly absorbs water from the atmosphere. When present in DMSO compound solutions, water can accelerate degradation and precipitation. Understanding DMSO hydration in an HTS compound library can improve storage and screening methods by managing the impact of water on compound stability. A non-destructive, acoustic method compatible with HTS has been developed to measure water content in DMSO solutions. Performance of this acoustic method was compared with an optical technique and found to be in good agreement. The accuracy and precision of acoustic measurements was shown to be under 3% over the tested range of DMSO solutions (0% to 35% water by volume) and insensitive to the presence of HTS compounds at typical storage concentrations. Time course studies of hydration for wells in 384-well and 1536-well microplates were performed. Well geometry, fluid volume, well position and atmospheric conditions were all factors in hydration rate. High rates of hydration were seen in lower-volume fills, higher-density multi-well plates and when there was a large differential between the humidity of the lab and the water content of the DMSO. For example, a 1536-well microplate filled with 2microL of 100% DMSO exposed for one hour to a laboratory environment with approximately 40% relative humidity will absorb over 6% water by volume. Understanding DMSO hydration rates as well as the ability to reverse library hydration are important steps towards managing stability and availability of compound libraries.


Assuntos
Dimetil Sulfóxido/química , Água/química , Acústica , Técnicas de Química Combinatória , Óptica e Fotônica
14.
Diabetologia ; 48(9): 1851-9, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16012821

RESUMO

AIMS/HYPOTHESIS: There are three members of the glucose-6-phosphatase (G6Pase) family: (1) the liver/kidney/intestine G6Pase-alpha (encoded by G6PC), which is a key enzyme in glucose homeostasis; (2) the ubiquitous G6Pase-beta (encoded by G6PC3); and (3) the islet-specific G6Pase-related protein (IGRP, encoded by /G6PC2). While G6Pase-alpha and G6Pase-beta are functional glucose-6-phosphate hydrolases, IGRP possesses almost no hydrolase activity. This was unexpected since G6Pase-alpha is more closely related to IGRP than G6Pase-beta. Recently, amino acids 206-214 in IGRP were identified as a beta cell antigen targeted by a prevalent population of pathogenic CD8+ T cells in autoimmune diabetes, suggesting that this peptide confers functional specificity to IGRP. We therefore investigated the molecular events that inactivate IGRP activity and the effects of the beta cell antigen sequence on the stability and enzymatic activity of G6Pase-alpha. METHODS: Studies were performed using site-directed mutagenesis and transient expression assays. Protein stability was evaluated by Western blotting, proteasome inhibitor studies and in vitro transcription-translation. RESULTS: We showed that the residues responsible for G6Pase activity are more extensive than previously recognised. Introducing the IGRP antigenic motif into G6Pase-alpha does not completely destroy activity, although it does destabilise the protein. The low hydrolytic activity in IGRP is due to the combination of multiple independent mutations. CONCLUSIONS/INTERPRETATION: The loss of catalytic activity in IGRP arises from the sum of many sequence differences. G6Pase-alpha mutants containing the beta cell antigen sequence are preferentially degraded in cells, which prevents targeting by pathogenic CD8+ T cells. It is possible that IGRP levels in beta cells could dictate susceptibilities to diabetes.


Assuntos
Glucose-6-Fosfatase/fisiologia , Ilhotas Pancreáticas/fisiologia , Monoéster Fosfórico Hidrolases/metabolismo , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Sequência de Bases , Células COS , Chlorocebus aethiops , Clonagem Molecular , Sequência Conservada , Primers do DNA , Cães , Glucose-6-Fosfatase/química , Glucose-6-Fosfatase/genética , Humanos , Ilhotas Pancreáticas/enzimologia , Camundongos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Ratos , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
15.
Cloning Stem Cells ; 7(2): 95-106, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15971983

RESUMO

Therapeutic cloning by somatic cell nuclear transfer offers potential for treatment of a wide range of degenerative disease. Nuclear transplantation with neo (r)-marked somatic nuclei from 10-13-year-old cows was used to generate cloned bovine fetuses. Clone fetal liver (FL) hematopoietic stem cells (HSC) were transplanted into two busulfan-treated and one untreated nuclear donor cows. Hematopoiesis was monitored over 13-16 months by in vitro progenitor and HSC assays. Chimerism was demonstrated by PCR in blood, marrow, lymph nodes, and endothelium, peaking at levels of 9-17% in blood granulocytes but at lower levels in lymphocyte subsets (0.1-0.01%). Circulating progenitors showed high levels of chimerism (up to 60% neo (r+)) with persisting fetal features. At sacrifice, the animal that had no pre-transplant myelosupression showed persisting donor cells in blood and lymph nodes, and in marrow 0.25% of progenitor cells and a detectable fraction of stem cells were neo (r+). The fetal HSC showed a 10-fold competition advantage over adult HSC. Cloning generated histocompatible HSC capable of long-term multilineage engraftment in a large animal model.


Assuntos
Células Clonais , Células-Tronco Hematopoéticas/citologia , Animais , Sequência de Bases , Células da Medula Óssea/citologia , Bovinos , Células Cultivadas , Primers do DNA , Endotélio Vascular/citologia , Fígado/citologia , Fígado/embriologia , Linfonodos/citologia , Reação em Cadeia da Polimerase , Transplante de Células-Tronco
16.
Dis Aquat Organ ; 63(1): 53-60, 2005 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-15759800

RESUMO

Five (2 IgG, 3 IgM) monoclonal antibodies (MAbs) against the G9508KS strain of grouper nervous necrosis virus (GNNV) were produced and characterized. All 5 MAbs showed positive signals in the retina of GNNV-infected grouper larvae and in the cytoplasm of GNNV-infected GF-1 cells using immunohistochemistry staining. Two MAbs reacted with the denatured capsid protein derived from GNNV-infected GF-1 cells in Western blot analysis, but did not react with the GNNV recombinant capsid protein expressed by E. coli in an indirect immnunosorbent assay (ELISA). All 5 MAbs were able to neutralize GNNV, tiger puffer NNV (TPNNV) and barfin flounder NNV (BFNNV), while only 2 of the MAbs neutralized striped jack NNV (SJNNV). A capture ELISA system based on the use of MAbs for capture and a rabbit polyclonal antibody for detection was developed. When absorbance values higher than 0.5 were judged to be positive, the sensitivity of the capture ELISA system was 2.5 ng per well of purified GNNV protein or 6.5 x 10(4) TCID50 per well of GNNV supernatant from culture cells. This capture ELISA system could become a more specific and sensitive tool for NNV diagnosis in the field and in routine laboratories.


Assuntos
Anticorpos Monoclonais/imunologia , Antígenos Virais/análise , Ensaio de Imunoadsorção Enzimática/veterinária , Peixes/virologia , Nodaviridae/imunologia , Animais , Anticorpos Monoclonais/metabolismo , Proteínas do Capsídeo/metabolismo , Ensaio de Imunoadsorção Enzimática/métodos , Peixes/imunologia , Immunoblotting/veterinária , Imuno-Histoquímica/veterinária , Larva/virologia , Testes de Neutralização/veterinária , Nodaviridae/classificação , Retina/virologia , Especificidade da Espécie
17.
Stem Cells ; 22(3): 283-91, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15153606

RESUMO

The purpose of this study was to improve the transduction efficiency of adenoviral vectors (Ad) in human CD34+ hematopoietic progenitor cells. CD34+ cells from cord blood or mobilized peripheral blood were incubated with tumor necrosis factor-alpha (TNF-alpha). After removal of free TNF-alpha, the cells were infected with an Ad encoding green fluorescent protein (GFP). One day later, viable cells were counted and analyzed for GFP and CD34 by flow cytometry. To visualize vectoral trafficking, CD34+ cells were incubated with fluorophore-conjugated Ad. Plating efficiencies of hematopoietic progenitors before and after transduction were evaluated by methylcellulose assays. Pretreatment with TNF-alpha increased the transduction efficiency more than twofold (39.2% versus 15.5%) in a dose-dependent manner and strongly improved the survival of GFP-positive CD34+ cells. Time course experiments showed that TNF-alpha incubation times as short as 10 minutes were still effective. Neutralizing antibodies to TNF receptor II and RGD peptides diminished the TNF-alpha-dependent increase in transduction efficiency. No TNF-alpha-dependent increase in adenoviral receptors (coxsackie-adenovirus receptor, alphavbeta3-integrin) occurred. Analysis of viral binding demonstrated a significantly higher incidence of local concentrations of Ad along the cell surface (caps) in virus-positive cells of the TNF-alpha-treated group. Plating efficiency, especially the formation of granulocyte-macrophage colony forming units, was enhanced by TNF-alpha pretreatment. We conclude that brief incubation with TNF-alpha before addition of the Ad significantly increased the Ad transduction efficiency in CD34+ cells, and improved post-transduction survival of progenitors of the granulocyte-macrophage lineage. This finding correlates with increased Ad capping at the cell surface and suggests an alteration of Ad trafficking.


Assuntos
Adenoviridae , Células-Tronco Hematopoéticas/fisiologia , Transdução Genética , Fator de Necrose Tumoral alfa/fisiologia , Antígenos CD34 , Sangue Fetal/citologia , Citometria de Fluxo , Vetores Genéticos , Humanos , Oligopeptídeos/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo
18.
Leukemia ; 18(4): 777-87, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-14961038

RESUMO

The Notch family of transmembrane receptors has been implicated in the regulation of many developmental processes. In this study, we evaluated the role of Notch4 in immature hematopoietic progenitors by inducing, with retroviral transduction, enforced expression of Int-3, the oncogenic and constitutively active form of mouse Notch4. Int-3-transduced human myeloid leukemia (HL-60) cells demonstrated significantly delayed expression of differentiation markers following retinoic acid and 12-0-tetradecanoylphorbol 13-acetate treatment. Furthermore, HL-60 cells expressing Int-3 displayed a slower growth rate than cells infected with void virus, and accumulation in the G0/G1 phases of cell cycle. Transduction with deletion mutants of Int-3 defined the importance of individual domains of the protein (in particular, the ANK domain and the C-terminal domain) in the inhibition of differentiation and growth arrest of HL-60 cells. When mouse bone marrow enriched for stem cells (5-fluorouracil-resistant, lineage negative) was transduced and cultured for two weeks, the Int-3-transduced population displayed a lower expression of differentiation markers and a three- to five-fold higher frequency of colony-forming cells (CFU-GM/BFU-E) than control cultures. These results strongly support the notion that Notch signaling inhibits differentiation and promotes expansion of hematopoietic stem/progenitor cells.


Assuntos
Células-Tronco Hematopoéticas/citologia , Mielopoese , Proteínas Proto-Oncogênicas/fisiologia , Receptores de Superfície Celular , Animais , Diferenciação Celular/efeitos dos fármacos , Divisão Celular , Linhagem Celular , Células HL-60 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Células Mieloides , Ésteres de Forbol/farmacologia , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Proto-Oncogênicas/genética , Receptor Notch4 , Receptores Notch , Transfecção , Tretinoína/farmacologia
19.
Dis Aquat Organ ; 55(3): 221-8, 2003 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-13677508

RESUMO

Viral nervous necrosis (VNN) is a worldwide disease among marine fishes. In Taiwan, NNN disease was first identified in 2 species of hatchery-reared grouper, Epinephelus fuscogutatus and E. akaaya in 1994. Since then, increasing mortalities have occurred among groupers Epinephelus spp., and also among European eels Anguilla anguilla L., yellow-wax pompano Trachinotus falcatus, firespot snapper Lutaanus erythropterus B., barramundi Lates calcarifer, cobias Rachycentron canadum, humpback groupers Cromileptes altivelis and Chinese catfish Parasilurus asotus. In the present study, samples were collected from affected fishes and processed for reverse transcriptase (RT) PCR amplification and virus isolation in cell culture. Infected cells (GF-1 cell line) exhibited cytopathic-effect characteristics of grouper nervous necrosis virus (GNNV). A RT-PCR product of approximately 830 bp was amplified from the brain homogenate of tested samples and sequenced. The nucleotide and deduced amino acid sequences of the amplified RT-PCR products from all isolates were strongly homologous (> 97 %) with the corresponding region of the published sequence of red-spotted grouper nervous necrosis virus (RGNVV). Therefore, all Taiwan NNV (nervous necrosis virus) isolates studied in this report belong to the RGNNV genotype. We used 5 neutralizing monoclonal antibodies (MAbs) against GNNV to analyze the antigenic relationship of Taiwan NNV isolates and striped jack nervous necrosis virus (SJNNV). The results of neutralization tests revealed that all Taiwan NNV isolates were closely related, but antigenically different from SJNNV in 3 neutralizing epitopes. To our knowledge, this is the first description of NNV infection in European eels, yellow-wax pompano, firespot snapper, cobia and Chinese catfish, and the first reported instance of natural NNV infection in freshwater fishes causing high mortality.


Assuntos
Doenças dos Peixes/genética , Peixes/virologia , Nodaviridae/genética , Infecções por Vírus de RNA/genética , Infecções por Vírus de RNA/veterinária , RNA Viral/genética , Sequência de Aminoácidos , Animais , Aquicultura/métodos , Sequência de Bases , Mapeamento de Epitopos , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/imunologia , Doenças dos Peixes/virologia , Testes de Neutralização , Nodaviridae/imunologia , Nodaviridae/isolamento & purificação , Nodaviridae/patogenicidade , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Alinhamento de Sequência , Taiwan/epidemiologia
20.
Biotechniques ; 32(6): 1360-2, 1364-5, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12074167

RESUMO

The advantages of using 1, 96, or 384 precision glass syringes in automated high-throughput microdispensers in creating highly uniform and reproducible DNA, protein, and organic compound array filters and slides are described. Using the Hydra Microdispenser and Tango Liquid Handling system, 0.1-5 ng (in 50-300 nL) PCR-amplified, human cancer-related genes and housekeeping genes were spotted onto nylon membranes and coated slides. Protein solutions of 50 microg/mL to 1 mg/mL were spotted onto coated slides or onto MaxiSorp 96-well plates. Up to 6144 spots/membrane and up to 1000 spots/slide were printed. The size of the spots created by glass syringes was uniform and reproducible (precision variation of less than 5%) from spot to spot and membrane to membrane. Using a Tango 384 system, a total of ten 6144-spot filters can be produced in approximately 25 min, translating into a spotting speed of 2.5 min/membrane.


Assuntos
Análise de Sequência com Séries de Oligonucleotídeos/instrumentação , Seringas , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Proteínas/análise , Reprodutibilidade dos Testes
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