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1.
Rev Bras Farmacogn ; 32(3): 410-420, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35572718

RESUMO

Dengue fever has become one of the deadliest infectious diseases and requires the development of effective antiviral therapies. It is caused by members of the Flaviviridae family, which also cause various infections in humans, including dengue fever, tick-borne encephalitis, West Nile fever, and yellow fever. In addition, since 2019, dengue-endemic regions have been grappling with the public health and socio-economic impact of the ongoing coronavirus disease 19. Co-infections of coronavirus and dengue fever cause serious health complications for people who also have difficulty managing them. To identify the potentials of mangiferin, a molecular docking with various dengue virus proteins was performed. In addition, to understand the gene interactions between human and dengue genes, Cytoscape was used in this research. The Kyoto Encyclopedia of Genes and Genomes software was used to find the paths of Flaviviridae. The Kyoto Encyclopedia of Genes and Genomes and the Reactome Pathway Library were used to understand the biochemical processes involved. The present results show that mangiferin shows efficient docking scores and that it has good binding affinities with all docked proteins. The exact biological functions of type I interferon, such as interferon-α and interferon-ß, were also shown in detail through the enrichment analysis of the signaling pathway. According to the docking results, it was concluded that mangiferin could be an effective drug against the complications of dengue virus 1, dengue virus 3, and non-structural protein 5. In addition, computational biological studies lead to the discovery of a new antiviral bioactive molecule and also to a deeper understanding of viral replication in the human body. Ultimately, the current research will be an important resource for those looking to use mangiferin as an anti-dengue drug. Supplementary Information: The online version contains supplementary material available at 10.1007/s43450-022-00258-6.

2.
Indian J Med Microbiol ; 37(1): 127-131, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31424025

RESUMO

We report here the first case of pulmonary infection due to Mycobacterium kyorinense in a 55-year-old hypertensive woman treated for pulmonary tuberculosis earlier on two occasions. She presented with productive cough, intermittent episode of left-sided chest pain, loss of appetite, low-grade fever, and breathlessness. Sputum cultures revealed non-tuberculous mycobacteria (NTM). She remained persistently symptomatic with sputum cultures positive for acid-fast bacilli even after 6 months of treatment. Hence, a 16SrRNA gene amplification and sequencing were done that revealed M. kyorinense. Based on the guidelines of the American Thoracic Society, she was started on weight-based dosing of clarithromycin, levofloxacin, ethambutol, isoniazid and injection amikacin daily. The patient improved symptomatically and became culture-negative after 3 months of therapy with the above regimen and continued to be culture negative for 12 months of treatment. She continues to remain symptom-free without evidence of any clinical or bacteriological relapse.


Assuntos
Antituberculosos/uso terapêutico , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Mycobacterium/genética , Infecções Respiratórias/diagnóstico , Amicacina/uso terapêutico , Claritromicina/uso terapêutico , Etambutol/uso terapêutico , Feminino , Humanos , Isoniazida/uso terapêutico , Levofloxacino/uso terapêutico , Pessoa de Meia-Idade , Mycobacterium/isolamento & purificação , Infecções por Mycobacterium não Tuberculosas/microbiologia , RNA Ribossômico 16S/genética , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/microbiologia
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 136 Pt C: 1260-8, 2015 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-25456668

RESUMO

In this work, colorless crystals of 2-acetoxybenzoic acid were grown by slow evaporation method and the FT-IR and FT-Raman spectra of the sample were recorded in the region 4000-500cm(-1) and 4000-100cm(-1) respectively. Molecular structure is optimized with the help of density functional theory method (B3LYP) with 6-31+G(d,p), 6-311++G(d,p) basis sets. Stability of the molecule arising from hyperconjugation and charge delocalization is confirmed by the natural bond orbital analysis (NBO). The results show that electron density (ED) in the σ(∗) antibonding orbitals and E(2) energies confirms the occurrence of intramolecular charge transfer (ICT) within the molecule. The assignments of the vibrational spectra have been carried out with the help of normal coordinate analysis following the scaled quantum mechanical force field (SQMFF) methodology. The results of the calculations were applied to simulated spectra of the title compound, which show excellent agreement with observed spectra. The (1)H and (13)C nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated by GIAO method. Mulliken population analysis on atomic charges is also calculated. The calculated HOMO and LUMO energy gap shows that charge transfer occurs within the molecule.

4.
Mol Cell Biochem ; 387(1-2): 123-34, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24173620

RESUMO

The reversal effect of troxerutin (TX) on obesity, insulin resistance, lipid accumulation, oxidative damage, and hypertension induced in the high-fat-high-fructose diet (HFFD)-fed mice model of metabolic syndrome was investigated. Adult male Mus musculus mice of body weight 25-30 g were fed either control diet or HFFD. Each group was divided into two and treated or untreated with TX (150 mg/kg bw, p.o.) from the 16th day. Assays were done in plasma and heart after 30 and 60 days of the experimental period. Significant increase in the levels of glucose and insulin, blood pressure (BP), and oxidative stress were observed after 30 days of HFFD feeding as compared to control. Animals fed HFFD for 60 days developed more severe changes in the above parameters compared to those fed for 30 days. Hearts of HFFD-fed mice registered downregulation of peroxisome proliferator-activated receptor-α and peroxisome proliferator-activated receptor gamma coactivator-1α, carnitine palmitoyl transferse-1b and AMP-activated protein kinase; and upregulation of cluster of differentiation 36, fatty acid-binding protein-1, and sterol regulatory element-binding protein-1c after 60 days. TX administration restricted obesity (as seen by Lee's index); improved whole body insulin sensitivity; reduced BP, lipid accumulation, and oxidative damage; upregulated fatty acid (FA) oxidation; and downregulated FA transport and lipogenesis. Histology of heart revealed that TX diminishes inflammatory cell infiltration and fatty degeneration in HFFD-fed mice. The antioxidant property of TX and its ability to influence lipid regulatory genes could be the underlying mechanisms for its beneficial effects.


Assuntos
Antioxidantes/farmacologia , Dieta Hiperlipídica/efeitos adversos , Frutose/efeitos adversos , Hidroxietilrutosídeo/análogos & derivados , Miocárdio/metabolismo , Animais , Antioxidantes/uso terapêutico , Avaliação Pré-Clínica de Medicamentos , Proteínas de Transporte de Ácido Graxo/metabolismo , Expressão Gênica , Hidroxietilrutosídeo/farmacologia , Hidroxietilrutosídeo/uso terapêutico , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Síndrome Metabólica/tratamento farmacológico , Síndrome Metabólica/etiologia , Síndrome Metabólica/metabolismo , Camundongos , Miocárdio/patologia , Estresse Oxidativo , PPAR alfa/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo
6.
Bioresour Technol ; 97(18): 2481-4, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16815011

RESUMO

The laboratory bioassay of the essential oil and the isolated compounds from Chloroxylon swietenia against Aedes aegypti and Anopheles stephensi was carried out to evaluate the larvicidal activity. LC50 value estimated for A. aegypti and An. stephensi were 16.5 and 14.9 microg/ml and 20.2 and 19 microg/ml for leaf and stem oils, respectively. The three sesquiterpenes pregeijerene, geijerene and germacrene D were isolated and their Larvicidal activity was evaluated. Pregeijerene and geijerene were observed for the first time in the volatile constituents of C. swietenia, however, leaves contained higher amount of geijerene compared to stems.


Assuntos
Aedes/efeitos dos fármacos , Anopheles/efeitos dos fármacos , Inseticidas/análise , Óleos Voláteis/farmacologia , Rutaceae/química , Animais , Larva/efeitos dos fármacos , Dose Letal Mediana , Óleos Voláteis/química , Folhas de Planta/química , Caules de Planta/química , Sesquiterpenos/isolamento & purificação
7.
J Med Microbiol ; 52(Pt 8): 667-673, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12867560

RESUMO

Leptospirosis is a widespread zoonotic disease that affects all mammals in different parts of the world. Though there are many commercial kits available for the diagnosis of systemic leptospirosis, the nature of the antigen has not been described. Therefore, identification of a specific antigen is important. Since ocular involvement in leptospirosis has been reported, there is a need to identify and characterize the leptospiral antigen for diagnosis of uveitis associated with past leptospiral infection (leptospiral uveitis) and for confirming the clinical diagnosis. Seven-day-old culture of Leptospira biflexa serovar Patoc was used for preparing the antigen. The present study included serum samples from 81 patients with clinical criteria for leptospiral uveitis, 15 cataract controls and 15 non-leptospiral uveitis controls. Serum samples were assayed by ELISA using our antigenic preparation and by a microscopic agglutination test (MAT) using 19 serovars. The antigen prepared had 280 micro g LPS ml(-1) and no detectable amount of protein. Silver-staining of SDS-PAGE for protein and LPS, dot blot and Western blot analysis and proteinase K and periodate treatment showed that LPS (13-21 kDa and 28 kDa) in our preparation was the relevant antigen for serodiagnosis. IgG antibodies showed reactivity in both leptospiral uveitis patients and controls. However, on the basis of IgM response to LPS, 48 % of the leptospiral uveitis patients were significantly positive compared with controls; 58 % of leptospiral uveitis patients and none of the controls were positive for MAT. When MAT and IgM ELISA results were considered together, 77 % were significantly positive. LPS is identified as a candidate antigen for serodiagnosis of leptospiral uveitis and has sensitivity and specificity of 48 and 90 %, respectively, in ELISA for IgM antibodies. Confirmation of clinical diagnosis with a specific laboratory test would help to initiate the most appropriate treatment for leptospiral uveitis.


Assuntos
Antígenos de Bactérias/imunologia , Leptospira/imunologia , Leptospirose/complicações , Leptospirose/diagnóstico , Lipopolissacarídeos/imunologia , Uveíte/complicações , Uveíte/diagnóstico , Adulto , Anticorpos Antibacterianos/sangue , Feminino , Humanos , Leptospirose/imunologia , Masculino , Testes Sorológicos , Uveíte/imunologia
8.
Plant Foods Hum Nutr ; 52(3): 271-8, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9950088

RESUMO

Low cost supplementary products using maize were developed and made using extrusion. Beta-carotene rich sources like curry leaf, carrot, red palm oil were used at different level to increase vitamin A precursor Levels and, therefore, vitamin A. Incorporation of curry leaf powder and carrot powder at 30 percent level and 30:70 blend of red palm oil and groundnut oil were found to be more acceptable than the products made with other levels. These products were tasted for acceptability by preschool children and were analysed for energy, protein, fat and beta-carotene contents. The control, fresh and stored supplementary products contained 1.707, 1.922, 1.919 MJ, 11.0, 11.6, 10.36 g protein, 10.2, 10.4, 9.64 g fat, 0, 7.37, 6.72 mg beta-carotene per 100 g, respectively. The loss of beta-carotene in processing and storage of curry leaf and carrot supplemented products was 13.69, 6.25 and 20.24, 8.06 percent, respectively.


Assuntos
Suplementos Nutricionais , Zea mays , beta Caroteno/administração & dosagem , Criança , Pré-Escolar , Cor , Daucus carota , Manipulação de Alimentos , Conservação de Alimentos , Humanos , Óleo de Palmeira , Óleos de Plantas , Sensação , Especiarias , Paladar , beta Caroteno/análise
9.
Biochem J ; 310 ( Pt 1): 125-32, 1995 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-7646434

RESUMO

Neuronal thread proteins (NTPs) are molecules that accumulate in the brains of patients with Alzheimer's disease, and may play a key role in both normal and neurodegenerative neuritic sprouting. In this investigation we determined whether NTP expression is up-regulated by insulin, an important neurotrophic factor that stimulates differentiation-associated neurite outgrowth, and studied the effects of ethanol, a known inhibitor of growth factor receptor tyrosine phosphorylation, on NTP expression and insulin-mediated signal transduction cascade in neuronal [primitive neuroectodermal tumour cell line 2; (PNET2)] cells. PNET2 cells were treated with 50 m-units/ml insulin in the presence or absence of 100 mM ethanol for 0.2-96 h, and cell proliferation and expression of NTP molecules were investigated by metabolic labelling, immunoprecipitation and immunohistochemical staining. Insulin stimulation resulted in an immediate increase in the levels of three (38, 18 and 15 kDa) of five NTP species (the others were of 26 and 21 kDa), followed by a decline in expression within 120 min; however, studies performed up to 96 h of culture demonstrated up-regulation by insulin of all five NTP species. Ethanol either abolished or severely muted the short- and long-term insulin-mediated upregulation of NTP expression, and substantially reduced insulin-mediated neuronal differentiation. The effects of ethanol on NTP gene expression were associated with impaired insulin-mediated tyrosine phosphorylation of both the insulin receptor beta subunit and the insulin receptor substrate-1 (IRS-1), resulting in decreased association of phosphatidylinositol 3-kinase with IRS-1. The findings suggest that ethanol may inhibit NTP expression associated with central nervous system neuronal differentiation by uncoupling the IRS-1-mediated insulin signal transduction pathway.


Assuntos
Proteínas de Ligação ao Cálcio/genética , Etanol/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Insulina/farmacologia , Proteínas do Tecido Nervoso/genética , Fosfoproteínas/metabolismo , Tirosina/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Linhagem Celular , DNA/biossíntese , DNA/efeitos dos fármacos , Imunofluorescência , Humanos , Proteínas Substratos do Receptor de Insulina , Litostatina , Proteínas do Tecido Nervoso/metabolismo , Fosforilação , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima
10.
Int Immunol ; 7(4): 625-33, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7547690

RESUMO

In this study, a B cell growth stimulatory factor, constitutively secreted by a human CD4+ T cell hybridoma clone, MP6, has been purified and characterized. Serum-free 24 h culture media from MP6 cells were collected, concentrated by ultrafiltration and separated by gel chromatography. Fractions were analyzed for stimulatory activity using [3H]thymidine incorporation in normal and leukemic (B-CLL) B cells as target cells. Activity was present in a 12 kDa protein peak. Upon storage this lost activity indicating that the factor was sensitive to air oxidation, a well-known property of mammalian thioredoxins (Trxs). Treatment of the inactive fraction with dithiothreitol restored full activity. When culture medium was analyzed with a radioimmunoassay for human placenta Trx, the MP6 clone was shown to release 30-50 ng/ml per million cells during 24 h. The B cell stimulatory activity of the MP6 medium was removed by Sepharose-bound anti-human placenta Trx IgG and activity was recovered by elution from the antibodies. Furthermore, MP6 medium showed Trx activity with NADPH and Trx reductase using an insulin disulfide reduction assay. Starting from 5 l of serum-free MP6 conditioned medium, the Trx was purified approximately 100,000-fold. After gel electrophoresis banding, the material was analyzed by peptide sequencing and a full length sequence of an 104 amino acid long protein was obtained. This Trx sequence was identical to the previously published sequence of human Trx from HTLV-1 transformed T cells, adult T cell leukemia-derived factor/Trx.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Linfócitos B/fisiologia , Linfócitos T CD4-Positivos/metabolismo , Substâncias de Crescimento/isolamento & purificação , Tiorredoxinas/isolamento & purificação , Sequência de Aminoácidos , Anticorpos , Linfócitos B/efeitos dos fármacos , Linhagem Celular , Sistema Livre de Células , Cromatografia de Afinidade , Células Clonais , Meios de Cultivo Condicionados/análise , Citocinas/análise , Sinergismo Farmacológico , Substâncias de Crescimento/biossíntese , Substâncias de Crescimento/farmacologia , Humanos , Leucemia Linfocítica Crônica de Células B/metabolismo , Dados de Sequência Molecular , Radioimunoensaio , Tiorredoxinas/imunologia
11.
Alcohol Clin Exp Res ; 19(2): 441-6, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7542850

RESUMO

Ethanol inhibits insulin (IN) and epidermal growth factor (EGF)-induced hepatocyte DNA synthesis. Growth factor receptor kinases, such as IN and EGF, phosphorylate insulin receptor substrate (IRS-1) and p36 protein kinase substrate, respectively, on tyrosine residues. IRS-1 and p36 are thought to be important intracellular signal transduction molecules involved in the regulation of cell growth. These investigations explored the effect of ethanol additions on the expression and tyrosyl phosphorylation (TP) of p36 and IRS-1 in a human hepatocellular carcinoma cell line (FOCUS) in relationship to cell proliferation induced by IN and serum growth factor stimulation. It was found that p36 was constitutively and highly expressed in serum-starved cells and protein, and mRNA levels did not change with cell proliferation induced by growth factors. However, exposure of FOCUS cells to ethanol additions substantially inhibited TP of p36. The early TP of IRS-1 induced by IN stimulation was also reduced by ethanol additions. Finally, there was a parallel decrease of FOCUS cell proliferation in ethanol-exposed cultures. These studies suggest that one possible mechanism of ethanol inhibitory effect on cell proliferation is through reduced TP of putative intracellular signal transduction molecules, such as p36 and IRS-1.


Assuntos
Anexina A2/genética , Etanol/farmacologia , Fosfoproteínas/genética , Células Tumorais Cultivadas/efeitos dos fármacos , Tirosina/análogos & derivados , Carcinoma Hepatocelular , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Replicação do DNA/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas Substratos do Receptor de Insulina , Neoplasias Hepáticas , Fosforilação , Fosfotirosina , RNA Mensageiro/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Tirosina/metabolismo
12.
J Neurol Sci ; 128(2): 122-33, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7738588

RESUMO

p36 is a calcium/lipid-binding phosphoprotein that is expressed at high levels in proliferating and transformed cells, and at low levels in terminally differentiated cells, such as CNS neurons. The calcium-dependent binding to membrane phospholipids, and its capacity to interact with intermediate filament proteins suggest that p36 may be involved in the transduction of extracellular signals. The present work examines p36 gene expression in the mature CNS, primary primitive neuroectodermal tumors (PNETs), and transformed PNET cell lines. p36 immunoreactivity was not observed in normal adult human brain, but low levels of the protein were detected by Western blot analysis. Following acute anoxic cerebral injury, the mean levels of p36 protein were elevated two-fold, and injured neurons exhibited increased p36 immunoreactivity. This phenomenon was likely to have been mediated by post-transcriptional mechanisms since there was no corresponding change in the level p36 mRNA. p36 immunoreactivity was detected in 8 of 9 primary PNETs, and in 3 of 3 neurofilament-expressing PNET cell lines. The levels of p36 protein in PNET cell lines were 5-fold higher than in adult human brain tissue. Although p36 gene expression was generally high in proliferating PNET cells, the levels of p36 mRNA and protein were not strictly correlated with DNA synthesis. Instead, p36 gene expression was modulated in both proliferating and non-proliferating PNET cell cultures by treatment with 50 mIU/ml of insulin, 100 mM ethanol, or 5 microM retinoic acid. The frequent discordances observed experimentally and in vivo between p36 mRNA and p36 protein expression suggest that the steady-state levels of p36 protein in neuronal cells may be regulated primarily by post-transcriptional mechanisms.


Assuntos
Anexina A2/biossíntese , Astrocitoma/metabolismo , Isquemia Encefálica/metabolismo , Neoplasias Encefálicas/metabolismo , Regulação da Expressão Gênica , Hipóxia Encefálica/metabolismo , Proteínas de Neoplasias/biossíntese , Proteínas do Tecido Nervoso/biossíntese , Tumores Neuroectodérmicos Primitivos/metabolismo , Neurônios/metabolismo , Adulto , Animais , Anexina A2/genética , Encéfalo/metabolismo , Diferenciação Celular/efeitos dos fármacos , Etanol/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/patologia , Glioma/patologia , Humanos , Insulina/farmacologia , Lipídeos de Membrana/metabolismo , Proteínas de Neoplasias/genética , Proteínas do Tecido Nervoso/genética , Neuritos/efeitos dos fármacos , Neuritos/ultraestrutura , Neuroblastoma/patologia , Neurônios/efeitos dos fármacos , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Neoplásico/biossíntese , RNA Neoplásico/genética , Ratos , Transcrição Gênica , Tretinoína/farmacologia , Células Tumorais Cultivadas
13.
J Mol Neurosci ; 6(2): 91-108, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8746448

RESUMO

Neuronal thread proteins (NTPs) are a family of developmentally regulated molecules expressed in central nervous system (CNS) neurons and primitive neuroectodermal tumor (PNET) cell lines. NTP gene expression is modulated with DNA synthesis, neuritic sprouting, and neuronal differentiation. The present study explores the mechanism of insulin modulation of NTP gene expression during neuronal differentiation using PNET cell lines of CNS origin. PNET2 cells underwent neuronal differentiation with neurite outgrowth coupled with transient up-regulation of several species of NTP. In contrast, PNET1 cells failed to differentiate in response to insulin stimulation, although insulin receptors were more abundant than in PNET2 cells. Analysis of the insulin-mediated signal transduction pathway demonstrated that the lack of insulin responsiveness in PNET1 cells was primarily caused by impaired insulin-mediated tyrosyl phosphorylation of the insulin receptor substrate-1 (IRS-1). Correspondingly, the association between phosphatidyl-inositol 3 (PI3) kinase and phosphorylated IRS-1 was reduced in PNET1 compared with PNET2 cells. In contrast, the levels of IRS-1 protein were similar in PNET1 and PNET2 cells, and expression of the insulin receptor beta subunit (Ir beta) and insulin-mediated tyrosyl phosphorylation of the Ir beta were greater in PNET1 than PNET2 cells. The findings suggest that insulin effected neuronal differentiation and modulation of NTP gene expression in PNET cells utilizes a signal transduction cascade that requires tyrosyl phosphorylation of IRS-1.


Assuntos
Proteínas de Ligação ao Cálcio/biossíntese , Diferenciação Celular/fisiologia , Expressão Gênica/efeitos dos fármacos , Insulina/farmacologia , Fosfoproteínas/metabolismo , Western Blotting , Proteínas de Ligação ao Cálcio/análise , Proteínas de Ligação ao Cálcio/isolamento & purificação , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , DNA de Neoplasias/biossíntese , DNA de Neoplasias/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Proteínas Substratos do Receptor de Insulina , Cinética , Litostatina , Proteínas do Tecido Nervoso/biossíntese , Tumores Neuroectodérmicos Primitivos Periféricos , Fosfoproteínas/biossíntese , Fosforilação , Transdução de Sinais , Células Tumorais Cultivadas
14.
Biochem Biophys Res Commun ; 196(3): 1454-8, 1993 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-7504477

RESUMO

p36 plays a direct role in DNA synthesis and is overexpressed in transformed cells. It is also an important component linking the cell membrane to intracellular cytoskeletal components. Experiments were performed in primary rat hepatocyte culture stimulated with epidermal growth factor (EGF) to determine if p36 expression was related to DNA synthesis or to the effect of the extracellular matrix on hepatocyte differentiation; ethanol was employed as an agent to inhibit hormone stimulated hepatocyte DNA synthesis. It was found that hepatocyte p36 expression was highly dependent on the type of extracellular matrix and the time in culture. There was no correlation of p36 expression with DNA synthesis and, therefore, p36 levels appeared more closely related to the differentiated phenotype, induced by the extracellular matrix interactions rather than cellular proliferation.


Assuntos
Anexina A2/biossíntese , Etanol/farmacologia , Matriz Extracelular/fisiologia , Fígado/metabolismo , Proteínas Quinases/metabolismo , Animais , Northern Blotting , Células Cultivadas , Colágeno/farmacologia , DNA/biossíntese , Combinação de Medicamentos , Fator de Crescimento Epidérmico/farmacologia , Feminino , Cinética , Laminina/farmacologia , Fígado/efeitos dos fármacos , Proteoglicanas/farmacologia , RNA/análise , Ratos , Especificidade por Substrato , Timidina/metabolismo , Fatores de Tempo
15.
Cancer Res ; 52(10): 2823-9, 1992 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-1316229

RESUMO

In the current study we sought to elucidate the molecular mechanisms which might contribute to hepatocarcinogenesis in a hepatitis B virus (HBV) envelope transgenic mouse model in which chronic hepatocellular injury and inflammation lead to regenerative hyperplasia and eventually to the development of chromosomal abnormalities and hepatocellular carcinoma (HCC), thereby reiterating many of the pathophysiological events that occur prior to the development of HCC in chronic HBV infection in humans. We have previously demonstrated that HBV envelope gene expression is decreased in regenerating hepatocytes and preneoplastic nodules early in the disease process and that expression of alpha-fetoprotein and the multidrug transporter gene mdr-III is activated in the tumors that develop in this model, but not prior to tumor development. In the current study, we examined the structure and expression of a large panel of dominant acting oncogenes and tumor suppressor genes in the liver at all stages of the disease process in order to determine the extent to which they contribute to hepatocarcinogenesis in these transgenic mice. To our surprise, no changes were observed in the structure or function of any of these genes, many of which are commonly activated in other rodent models of hepatocarcinogenesis but rarely activated in human HCC. These findings suggest that the HBV transgenic mouse model is different from most other rodent models of hepatocarcinogenesis and that it may relate more closely to the events involved in HBV-induced human hepatocarcinogenesis, where generalized chromosomal abnormalities are common, while structural and functional changes in most of the commonly studied positive-acting oncogenes examined herein are not. Since p53 and RB mutations have recently been reported to be late events in human hepatocarcinogenesis, the structural integrity of the RB locus and the absence of p53 mutations in the HBV transgenic mouse model suggest that they may represent a relatively early stage of hepatocellular tumorigenesis and that further manipulation of this model is warranted in order to more fully reproduce the molecular-genetic events that characterize HBV-induced HCC in humans.


Assuntos
Carcinoma Hepatocelular/genética , Genes Supressores de Tumor/genética , Vírus da Hepatite B/genética , Neoplasias Hepáticas Experimentais/genética , Oncogenes/genética , Animais , Sequência de Bases , Carcinoma Hepatocelular/microbiologia , Modelos Animais de Doenças , Expressão Gênica/genética , Genes do Retinoblastoma/genética , Genes myc/genética , Genes p53/genética , Genes ras/genética , Neoplasias Hepáticas Experimentais/microbiologia , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular
16.
Virus Res ; 12(4): 331-48, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2471370

RESUMO

Fifteen stable mouse spleen cell myeloma hybrids (hybridomas) producing monoclonal antibodies to rinderpest virus proteins were produced. The specificity of these monoclonal antibodies was established by radioimmunoprecipitation followed by polyacrylamide gel analysis and immunofluorescence. Nine antibodies were specific for the surface glycoprotein H. All the nine clones showed inhibition of haemagglutination by measles virus. The antibodies from two clones (A7D2 and B2F6) neutralise infectious virus. Six clones produce antibodies reacting with the nucleocapsid protein N. Three antigenic sites designated I-III, with sites I and II partially overlapping, were topographically mapped on the H molecule by competitive binding assay. Similarly, two antigenic sites I and II were delineated on the N protein. The monoclonal antibodies were used to study the antigenic relationships of H and N proteins of rinderpest virus, measles virus and canine distemper virus.


Assuntos
Anticorpos Monoclonais/isolamento & purificação , Anticorpos Antivirais/isolamento & purificação , Capsídeo/imunologia , Hemaglutininas Virais/imunologia , Vírus da Peste Bovina/imunologia , Proteínas do Core Viral/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Especificidade de Anticorpos , Antígenos Virais/imunologia , Epitopos/imunologia , Hibridomas/imunologia , Camundongos , Células Vero
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