Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
1.
Zhonghua Yi Xue Za Zhi ; 103(23): 1781-1786, 2023 Jun 20.
Artigo em Chinês | MEDLINE | ID: mdl-37305938

RESUMO

Objective: To investigate the clinical efficacy and safety of 125I seed implantation in the treatment of mediastinal lymph node metastasis of lung cancer. Methods: Clinical data of 36 patients who underwent CT-guided 125I seed implantation for mediastinal lymph node metastasis of lung cancer from August 2013 to April 2020 in three hospitals of the Northern radioactive particle implantation treatment collaboration group were retrospectively collected, including 24 males and 12 females, aged 46 to 84 years. Cox regression model was used to analyze the relationship between local control rate, survival rate and tumor stage, pathological type, postoperative D90, postoperative D100 and other variables, and to analyze the occurrence of complications. Results: The objective response rate of CT-guided 125I seed implantation in the treatment of mediastinal lymph node metastasis of lung cancer was 75% (27/36), the median control time was 12 months, the 1-year local control rate was 47.2% (17/36), and the median survival time was 17 months. The 1-year and 2-year survival rates were 61.1% (22/36) and 22.2% (8/36) respectively. Univariate analysis showed that in the treatment of mediastinal lymph node metastasis with CT-guided 125I implantation, factors related to local control included tumor stage (HR=5.246, 95%CI: 2.243-12.268, P<0.001), postoperative D90 (HR=0.191, 95%CI: 0.085-0.431, P<0.001), postoperative D100 (HR=0.240, 95%CI: 0.108-0.533, P<0.001); The factors affecting survival were tumor stage (HR=2.712, 95%CI: 1.356-5.425, P=0.005), postoperative D90 (HR=0.110, 95%CI: 0.041-0.294, P<0.001), postoperative D100 (HR=0.212, 95%CI: 0.092-0.489, P<0.001). Multivariate analysis showed that tumor stage (HR=5.305, 95%CI: 2.187-12.872, P<0.001) and postoperative D100 (HR=0.237, 95%CI: 0.099-0.568, P<0.001) were correlated with local control rate. Tumor stage (HR=2.347, 95%CI: 1.095-5.032, P=0.028) and postoperative D90 (HR=0.144, 95%CI: 0.051-0.410, P<0.001) were correlated with survival. In terms of complications, 9 of the 36 patients had pneumothorax, and 1 of them was cured by closed thoracic drainage for severe pneumothorax; 5 cases developed pulmonary hemorrhage and 5 cases developed hemoptysis, which recovered after hemostasis treatment. One case developed pulmonary infection and recovered after anti-inflammatory treatment. No radiation esophagitis and radiation pneumonia occurred; No grade 3 or higher complications occurred. Conclusion: 125I seed implantation in the treatment of lung cancer mediastinal lymph node metastasis has a high local control rate and controllable adverse effects.


Assuntos
Neoplasias Pulmonares , Pneumotórax , Feminino , Masculino , Humanos , Metástase Linfática , Estudos Retrospectivos , Resultado do Tratamento
2.
Poult Sci ; 101(11): 102153, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36179650

RESUMO

The objective of this experiment was to investigate the effects of betaine on growth performance, serum parameters, intestinal health, and immune performance of goslings in response to lipopolysaccharide (LPS) challenge. A total of 168 healthy male 15-day-old Jiangnan White Goslings were randomly divided into 4 groups, with 6 replicates per treatment and seven goslings per replicate. A 2 × 2 factorial arrangement included 2 factors, that is, LPS challenge (injection of LPS or physiological saline) and betaine (added 0 or 0.06% betaine in diet). The results indicated that LPS challenge significantly reduced the average daily feed intake (ADFI), average daily gain (ADG), and body weight (BW) at 21 D of the goslings, while dietary betaine supplementation tended to increase the ADFI during the LPS stress period (P = 0.08) and BW at 21 D of the goslings (P = 0.09). The LPS-challenged goslings showed higher pro-inflammatory cytokines (interleukin-1 [IL-1ß], interleukin-6 [IL-6], tumor necrosis factor-α (TNF-α), and Interferon-gamma [IFN-γ]) and lower anti-inflammatory cytokine (Interleukin-10 [IL-10]) (P < 0.05) at 21 D of age. Dietary betaine supplementation alleviated LPS-induced increase in pro-inflammatory cytokines. The LPS challenge significantly decreased duodenal and jejunal villus height (VH) and villus height and crypt depth ratio (VCR), while the addition of betaine significantly increased duodenal VH and VCR (P < 0.05). On the other hand, addition of betaine significantly alleviated decline of enzyme activity on lipase, amylase, trypsin, and chymotrypsin in the intestinal of goslings. The LPS challenge significantly increased the content of serum D-lactic acid (D-LA) and the activity of diamine oxidase (DAO) at 21 D of the goslings. The LPS challenge and betaine addition significantly increased the mRNA expression of Occcludin (OCLN) in jejunal mucosa at 28 D of the goslings (P < 0.05). In conclusion, our research demonstrated that betaine can alleviate the decline of growth performance and immune performance in goslings caused by LPS. The results also indicate betaine possesses anti-inflammation properties and improves intestinal barrier functions. We recommend that 0.06% betaine be added into the diet to improve the intestinal health and immune performance of goslings.


Assuntos
Betaína , Lipopolissacarídeos , Animais , Masculino , Lipopolissacarídeos/toxicidade , Betaína/farmacologia , Galinhas/metabolismo , Suplementos Nutricionais , Gansos/metabolismo , Dieta/veterinária , Imunidade , Citocinas/genética , Citocinas/metabolismo , Ração Animal/análise
4.
Int Endod J ; 54(3): 377-387, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33090483

RESUMO

AIM: To examine the type of vesicular glutamate transporter (VGLUT)-immunopositive (+) axons that coexpress neuropeptides in the rat and human dental pulp, which may help understand peripheral mechanism of pulpal inflammatory pain in rats and humans. METHODOLOGY: The trigeminal ganglia (TG) and the dental pulp of the maxillary molar teeth from three male Sprague-Dawley rats weighing 300-330 g and dental pulps of three healthy human (male) maxillary premolar teeth from three 16 to 28-year-old patients extracted for orthodontic treatment were used. The type of VGLUT + axons that coexpress substance P (SP)- and/or calcitonin gene-related peptide (CGRP) and parvalbumin in the rat TG and in the axons of the rat and the human dental pulp was examined by double fluorescence immunohistochemistry and quantitative analysis. Results were analyzed using one-way anova and the Kruskal-Wallis test. RESULTS: SP and CGRP were expressed in many human VGLUT1 + pulpal axons but not in the rat VGLUT1 + TG neurons and pulpal axons (P < 0.05). SP and CGRP were expressed in a considerable number of human VGLUT2 + pulpal axons and also in many rat TG neurons and pulpal axons. The fraction of VGLUT1 + axons expressing parvalbumin was about three times higher in the rat than in the human dental pulp (P < 0.05). CONCLUSIONS: These findings suggest that the types of VGLUT + axons, which release neuropeptides, may be different between the rat and the human dental pulp, raising a possibility that peripheral mechanism of pulpal inflammatory pain may be different between rats and humans.


Assuntos
Neuropeptídeos , Proteínas Vesiculares de Transporte de Glutamato , Animais , Axônios , Polpa Dentária , Humanos , Ratos , Ratos Sprague-Dawley
5.
Hum Exp Toxicol ; 35(5): 511-25, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26205530

RESUMO

The purpose of the present study is to establish a new animal model of azithromycin (AZ)-induced liver injury and study the molecular pathological change during the process. First, mice were respectively injected intraperitoneally with AZ of different high doses. Our results showed that 800 mg/kg AZ injection significantly induced liver injury in the mice, which reflected an ideal process of liver injury and repair. In this study, we analyzed the molecular pathological changes during the process by hematoxylin and eosin staining, immunohistochemistry, Western blot, and quantitative real-time reverse transcription polymerase chain reaction in the liver of mice at 0, 12, 24, 48, and 72 h after 800 mg/kg injection. Our results showed that the expression of heat shock protein 70, proliferating cell nuclear antigen, vascular endothelial growth factor, caspase 3, and cytochrome P450 2E1 were significantly differently expressed during liver injury induced by 800 mg/kg AZ in mice. Our results will be conducive for further study of the pathogenesis and prevention of drug-induced liver injury.


Assuntos
Antibacterianos/toxicidade , Apoptose/efeitos dos fármacos , Azitromicina/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Modelos Animais de Doenças , Expressão Gênica/efeitos dos fármacos , Animais , Western Blotting , Caspase 3/genética , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Citocromo P-450 CYP2E1/genética , Relação Dose-Resposta a Droga , Proteínas de Choque Térmico HSP70/genética , Imuno-Histoquímica , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos Endogâmicos BALB C , Antígeno Nuclear de Célula em Proliferação/genética , Fator A de Crescimento do Endotélio Vascular/genética
6.
Hum Exp Toxicol ; 34(11): 1053-72, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25585999

RESUMO

This study focuses on investigating the concrete role of a disintegrin and metalloproteinase 8 (ADAM8) in the progression of hepatocellular carcinoma (HCC). Mice received anti-ADAM8 monoclonal antibody (mAb) of 100 µg/100 µl, 200 µg/100 µl or 300 µg/100 µl, respectively, in phosphate-buffered saline (PBS) or PBS intervention during the progression of HCC induced by diethylnitrosamine. The survival rate, body weight, and relative liver weight were determined in the mice. Serum aspartate aminotransferase (AST), alanine aminotransferase (ALT) and α-fetoprotein (AFP) level, hematoxylin-eosin staining, the expression level of vascular endothelial growth factor A (VEGF-A), proliferating cell nuclear antigen (PCNA), caspase 3 (Casp3), B cell leukemia 2 (Bcl2), B cell leukemia 2-associated X protein (Bax), protein p53 (P53), and ADAM8 were detected in the mice at the end of the 24th week. Our results showed that anti-ADAM8 mAb intervention effectively improved the survival rate, reduced the body weight loss and increased the relative liver weight in mice in a dose-dependent manner (p < 0.05 or p < 0.01). Anti-ADAM8 mAb intervention also significantly lowered serum AST, ALT, and AFP levels (p < 0.05 or p < 0.01), slowed the progression of HCC (p < 0.05 or p < 0.01), induced the expression of Casp3, Bax, and P53 (p < 0.05 or p < 0.01), and inhibited the expression of VEGF-A, PCNA, and Bcl2 in the liver of mice (p < 0.05 or p < 0.01) in a dose-dependent manner compared with the mice receiving PBS intervention. Our study suggested that ADAM8 might promote the progression of HCC by regulating the expression of these factors. Anti-ADAM8 mAb intervention might be suitable as a potential method for HCC therapy.


Assuntos
Proteínas ADAM/metabolismo , Antígenos CD/metabolismo , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas de Membrana/metabolismo , Proteínas ADAM/imunologia , Alanina Transaminase/sangue , Animais , Anticorpos Monoclonais/farmacologia , Antígenos CD/imunologia , Aspartato Aminotransferases/sangue , Carcinoma Hepatocelular/patologia , Caspase 3/genética , Caspase 3/metabolismo , Dietilnitrosamina , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas/patologia , Masculino , Proteínas de Membrana/imunologia , Camundongos Endogâmicos BALB C , Antígeno Nuclear de Célula em Proliferação/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , alfa-Fetoproteínas/análise , Proteína X Associada a bcl-2/metabolismo
7.
Br Poult Sci ; 51(1): 118-21, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20390576

RESUMO

1. A dose-response experiment with 5 dietary methionine concentrations (23, 33, 43, 53 and 63 g/kg) was conducted with goslings to estimate the growth performance and carcase quality response of growing goslings to dietary methionine from 28 to 70 d of age. 2. A total of 150, 28-d-old birds were randomly distributed to 15 pens with 10 birds per pen according to similar pen weight. There were 5 dietary treatments, each containing three replicate pens. Weight gain, feed intake and feed/gain of goslings from each pen were measured at 2-week intervals from 28 to 70 d of age. At 70 d of age, 4 goslings were selected randomly from each pen and slaughtered to evaluate carcase quality. 3. Significant effects of dietary methionine on daily weight gain (28-56 d) and daily feed intake were determined. Daily weight gain from 28 to 42 d and 28 to 56 d, daily feed intake and gain/feed showed significant quadratic response to increasing dietary methionine, while abdominal fat proportion showed a significant linear response. 4. When dietary CP concentration was 1582 g/kg, the optimal methionine concentrations for growing goslings from 28 to 42 d and 28 to 56 d of age for maximum daily weight gain were 407 and 4.14 g/kg, respectively.


Assuntos
Peso Corporal/fisiologia , Ingestão de Alimentos/fisiologia , Gansos/crescimento & desenvolvimento , Carne/normas , Metionina/farmacologia , Animais , Gansos/metabolismo , Distribuição Aleatória
8.
J Microsc ; 230(Pt 2): 167-71, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18445144

RESUMO

Compression and crevasses are common cutting artefacts in cryo-ultramicrotomy of vitreous sections. They can be reduced or suppressed under optimal cutting conditions. In the present study, compression and thickness were measured for different cutting speeds and knife angles. It was found that compression decreased with feed and that crevasses appeared only above a certain thickness. The optimal feed for vitreous sections was between 50 and 80 nm. The thickness, calculated by two independent methods, was quantitatively related to feed and compression.


Assuntos
Microscopia Crioeletrônica/métodos , Crioultramicrotomia/instrumentação , Enterococcus faecalis/ultraestrutura , Artefatos , Crioultramicrotomia/métodos , Enterococcus faecalis/crescimento & desenvolvimento , Secções Congeladas
9.
J Mater Sci Mater Med ; 19(8): 2845-50, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18338111

RESUMO

Calcium phosphate was deposited on carbon materials using a sonoelectrochemical method in an electrolyte containing calcium and phosphate ions. The effect of electrolyte concentration on sonoelectrochemically deposited calcium phosphate coatings was investigated and the underlying deposition mechanisms were discussed. The morphology, size and composition of the crystalline deposits changed with the electrolyte concentration. A mixture of plate, sphere and needle-like deposits was obtained at Ca(2+) ion concentrations greater than 16 mM, however needle-like hydroxyapatite (HA) was obtained at lower Ca(2+) concentrations. Analysis revealed that the sonoelectrochemical deposition of calcium phosphate consists of two processes-nucleation and crystal growth. The results suggest that the homogeneous nucleation of calcium phosphates in solution, followed by their absorption onto the carbon surface may account for the mechanism of coating observed at higher ionic concentrations. At lower concentrations, heterogeneous nucleation occurs on the surface of the carbon fibres, followed by the development of islands of crystal growth. The lower ionic concentration was shown to favour the generation of hydroxyapatite on carbon-based materials.


Assuntos
Fosfatos de Cálcio/química , Carbono/química , Eletrólitos/química , Eletroquímica , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier
10.
J Mater Sci Mater Med ; 19(4): 1787-91, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18157511

RESUMO

Calcium phosphate (CaP) coatings on carbon fabric substrate were produced by sonoelectrodeposition at different current densities (5, 8, 13, 20 and 34 mA/cm2). The surface morphology and chemical composition of the coatings were characterized by SEM, Raman and FTIR spectra. The results showed that at 5 mA/cm2 current density, the coating exhibits plate-like morphology, indicating an octacalcium phosphate (OCP) phase was pre-formed in the deposits and then converted into hydroxyapatite (HA). When the current density was increased to 8 mA/cm2 and higher, the coatings exhibited needle-like morphology corresponding to a HA phase. Furthermore, the sonoelectrodeposited CaP coating exhibited denser and more uniform structures with smaller crystal sizes as the current density increased. Cathodic reaction mechanisms of CaP coatings on carbon in the sonoelectrochemical processes are proposed to explain the different kinds of calcium phosphate obtained.


Assuntos
Fosfatos de Cálcio/química , Carbono/química , Materiais Revestidos Biocompatíveis , Eletroquímica/métodos , Cristalização , Durapatita/química , Desenho de Equipamento , Íons , Teste de Materiais , Microscopia Eletrônica de Varredura , Modelos Químicos , Osseointegração , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos , Propriedades de Superfície
11.
Vaccine ; 24(8): 1205-12, 2006 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-16202484

RESUMO

Trichinellosis is a serious parasitic zoonosis which is widely distributed in the world. Pork still is the predominant source of outbreaks of human trichinellosis in many countries. Vaccines are urgently needed to prevent swine from Trichinella infection. The gene (TspE1) encoding a 31 kDa antigen of T. spiralis was cloned to a eukaryotic expression plasmid pcDNA3 as DNA vaccine. The ability of the DNA vaccine to express antigen in mammalian CHO cells was previously confirmed by indirect fluorescencent antibody test (IFAT) and Western blotting. To evaluate its immunogenicity and its host protective potential, BALB/c mice were immunized with the DNA vaccine by intramuscular injection and gene-gun delivery. The serum antibody response was assayed by IFAT, enzyme linked immunosorbant assay (ELISA) and Western blotting. The cellular immune response was investigated by splenocyte proliferation assay. Vaccine administration by either route induced both humoral and cellular immune response against TspE1, which provided the partial protection against challenge infection with T. spiralis, as shown by significant reduction of larval burden in muscles. Thus, DNA immunization may offer an attractive alternative strategy against swine trichinellosis.


Assuntos
Trichinella spiralis/imunologia , Triquinelose/prevenção & controle , Vacinas de DNA/imunologia , Animais , Anticorpos Anti-Helmínticos/sangue , Ativação Linfocitária , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Vacinação
12.
Phytother Res ; 15(8): 718-20, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11746867

RESUMO

The antiviral effects of aqueous extracts of Terminalis chebula Retz., Sanguisorba officinalis L., Rubus coreanus Miq. and Rheum palmatum L. were examined by a cell culture system using a hepatitis B virus (HBV) producing cell line, HepG2 2.2.15. The extracts were assayed for the inhibition of HBV multiplication by measurement of HBV DNA and surface antigen (HBsAg) levels in the extracellular medium of HepG2 2.2.15 cells after an 8-day treatment. All extracts decreased the levels of extracellular HBV virion DNA at concentrations ranging from 64 to 128 microg/mL and inhibited the secretion of HBsAg dose dependently. Of the four tested plants, Terminalis chebula exhibited the most prominent anti-HBV activities.


Assuntos
Antivirais/farmacologia , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B/tratamento farmacológico , Fitoterapia , Extratos Vegetais/farmacologia , Rosácea , Antivirais/uso terapêutico , Southern Blotting , DNA Viral/efeitos dos fármacos , Frutas , Antígenos de Superfície da Hepatite B/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais/uso terapêutico , Raízes de Plantas , Células Tumorais Cultivadas/efeitos dos fármacos
13.
Se Pu ; 18(6): 568-70, 2000 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-12541754

RESUMO

The solid phase microextraction (SPME) has the advantages of high efficiency, high sensitivity, simple operation and solvent free operation for analyzing environmental samples. An optical fiber coated with mixed stationary phase of polysiloxane and polymeric fullerene (in ratio of 4:1) was used to extract 5 phthalic diesters by HS-SPME-GC. The operating conditions of SPME such as the extraction temperature, ionic strength of solution, adsorption time and desorption time have been studied. It was compared with commercial polymer coating PDMS fiber through headspace SPME combined with GC. The results indicated that OV-1/PSO-C60 was better than PDMS in extracting high boiling point and semi-volatile phthalic diesters. For phthalic diesters, the detection limits were in the range of 0.331 ng/L-12.5 micrograms/L, and relative standard deviations were below 12% except for dinonyl phthalate.


Assuntos
Dietilexilftalato/análise , Ácidos Ftálicos/análise , Poluentes da Água/análise , Cromatografia Gasosa/métodos , Cromatografia Líquida de Alta Pressão/métodos , Dibutilftalato/análise , Solventes
14.
Arch Pharm Res ; 22(5): 474-8, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10549574

RESUMO

Modulation of unscheduled DNA synthesis by dehydroepiandrosterone (DHEA) after exposure to various chemical carcinogens was investigated in the primary rat hepatocytes. Unscheduled DNA synthesis was induced by treatment of such direct acting carcinogens as methyl methanesulfonate (MMS) and ethyl methanesulfonate (EMS) or procarcinogens including benzo(a)pyrene (BaP) and 7,12-dimethylbenz(a)anthracene (DMBA). Unscheduled DNA synthesis was determined by measuring [methyl-3H]thymidine radioactivity incorporated into nuclear DNA of hepatocytes treated with carcinogens in the presence or absence of DHEA. Hydroxyurea (5x10(-3) M) was added to growth medium to selectively suppress normal replication. DHEA at concentrations ranging from 1x10(-6) M to 5x10(-4) M did not significantly inhibit unscheduled DNA synthesis induced by either MMS (1x10(-4) M) or EMS (1x10(-2) M). In contrast, DHEA significantly inhibited unscheduled DNA synthesis induced by BaP (6.5x10(-5) M) and DMBA (2x10(-5) M). DHEA-induced hepatotoxicity in rats was examined using lactate dehydrogenase (LDH) release as an indicator of cytotoxicity. DHEA exhibit no significant increase in LDH release compared with the solvent control at 18 h. These data suggest that nontoxic concentration of DHEA does not affect the DNA excision repair process, but it probably influence the enzymatic system responsible for the metabolic activation of procarcinogens and thereby decreases the amount of the effective DNA adducts formed by the ultimate reactive carcinogenic species.


Assuntos
Carcinógenos/toxicidade , DNA/biossíntese , Desidroepiandrosterona/fisiologia , Fígado/metabolismo , 9,10-Dimetil-1,2-benzantraceno/toxicidade , Animais , Benzo(a)pireno/toxicidade , Desidroepiandrosterona/farmacologia , Metanossulfonato de Etila/toxicidade , Técnicas In Vitro , L-Lactato Desidrogenase/metabolismo , Fígado/citologia , Fígado/efeitos dos fármacos , Masculino , Metanossulfonato de Metila/toxicidade , Ratos , Ratos Sprague-Dawley
15.
Res Commun Mol Pathol Pharmacol ; 101(1): 59-68, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9755844

RESUMO

We studied the effects of the neurotoxin, 6-hydroxydopamine (6-OHDA), on cultured fat-storing cells (FSCs) and hepatocytes. If either FSCs or hepatocytes were exposed to 6-OHDA for 4 hr, the neurotoxicant induced cell death in FSCs but not in hepatocytes. We decided to investigate why hepatocytes were refractile to injury from 6-OHDA while FSCs were labile. The activity of antioxidant enzymes within FSCs grown in vitro is remarkably lower than the activity in hepatocytes. Indeed, some specific antioxidant enzymes in FSCs were undetectable by our assays, but were easily detected in hepatocytes. Furthermore, the profile of antioxidant activity in FSCs was found to be almost identical to the profiles seen in cultured fibroblasts or myocytes. However, indirect immunolocalization of tyrosine hydroxylase in FSCs using anti-tyrosine hydroxylase antibodies was negative. Mazindol, a dopaminergic receptor antagonist, did not alleviate the toxicity of 6-OHDA suggesting that FSCs do not appear to possess a dopaminergic receptor. When the cell morphology of FSCs was examined by an indirect immunofluorescence technique, treatment of FSCs with 6-OHDA at a concentration of 200 microM for 2 hr modified the organization of alpha-smooth muscle actin into an irregular punctate pattern. Indeed, we found that the effects of 6-OHDA on cytoskeletal alterations and on the cell viability of FSCs were irreversible. These data suggest that : (1) 6-OHDA can cause irreparable injury to FSCs, but not hepatocytes; (2) hepatocytes are specially adapted to withstand an oxidative attack in contrast to FSCs. fibroblast and myocytes; (3) FSCs resemble other somatic cells in their low levels of antioxidant enzymes; and (4) this low profile of antioxidant activity may be responsible for the cell death and cytoskeletal alterations observed in FSCs in response to 6-OHDA.


Assuntos
Adipócitos/efeitos dos fármacos , Morte Celular , Citoesqueleto/efeitos dos fármacos , Fígado/citologia , Oxidopamina/farmacologia , Actinas , Adipócitos/citologia , Adipócitos/ultraestrutura , Animais , Antioxidantes/metabolismo , Células Cultivadas , Citoesqueleto/ultraestrutura , Inibidores da Captação de Dopamina/farmacologia , Glutationa/metabolismo , Fígado/efeitos dos fármacos , Fígado/ultraestrutura , Masculino , Mazindol/farmacologia , Estresse Oxidativo , Galato de Propila/farmacologia , Ratos , Ratos Wistar , Receptores Dopaminérgicos/fisiologia
16.
Jpn J Cancer Res ; 89(6): 597-603, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9703356

RESUMO

Gastric adenocarcinoma is the most prevalent cancer in South Korea, and Helicobacter pylori (H. pylori) infection is also common. This study was performed to examine the association between H. pylori infection and gastric cancer, taking into account various other factors. To investigate the association between gastric adenocarcinoma and H. pylori infection, determined by urease-positive reaction in the CLO test, a total of 175 paired specimens (175 tumor and 175 tissues adjacent to tumor) of stomach cancer patients and a total of 113 control specimens were obtained. The positive H. pylori infection rates were 78.9% (138/175) among the patients in specimens of tumor or tissues adjacent to the tumor and 41.6% (47/113) among controls in the CLO test. A positive correlation between H. pylori infection and gastric cancer was observed (age-adjusted odds ratio, 7.0; MH chi2=34.5 with P<0.0005). These data suggest that stomach cancer patients in Korea have high infection rates of H. pylori regardless of site specificity, and this infection might be causally associated with stomach cancer.


Assuntos
Adenocarcinoma/epidemiologia , Infecções por Helicobacter/epidemiologia , Helicobacter pylori/isolamento & purificação , Gastropatias/microbiologia , Neoplasias Gástricas/epidemiologia , Adenocarcinoma/microbiologia , Adulto , Idoso , Ensaios Enzimáticos Clínicos , Comorbidade , Infecções por Helicobacter/diagnóstico , Helicobacter pylori/enzimologia , Humanos , Coreia (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Estômago/enzimologia , Estômago/microbiologia , Neoplasias Gástricas/microbiologia , Urease/análise
17.
Mol Endocrinol ; 12(6): 810-4, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9626656

RESUMO

The role of the external third of helix VI of the angiotensin II (AII) AT1 receptor for the interaction with its ligand and for the subsequent signal transduction was investigated by individually replacing residues 252-256 by Ala, and residues 259 or 261 by Tyr, and permanently transfecting the resulting mutants to Chinese hamster ovary (CHO) cells. Binding experiments showed no great changes in affinity of any of the mutants for AII, [Sar1]-AII, or [Sar1, Leu8]-AII, but the affinity for the nonpeptide antagonist DuP753 was significantly decreased. The inositol phosphate response to AII was remarkably decreased in mutants V254A, H256A, and F259Y. These results indicate that AT1 residues Val254, His256, and Phe259 are not involved in ligand binding but participate in signal transduction. Based in these results and in others from the literature, it is suggested that, in addition to the His256 imidazole ring, the Phe259 aromatic ring interacts with the AII's Phe8, thus contributing to the signal-triggering mechanism.


Assuntos
Angiotensina II/metabolismo , Receptores de Angiotensina/fisiologia , Transdução de Sinais/fisiologia , Animais , Células CHO , Cricetinae , Cricetulus , Proteínas de Ligação ao GTP/fisiologia , Histidina/química , Humanos , Fosfatos de Inositol/fisiologia , Ligantes , Mutagênese Sítio-Dirigida , Fenilalanina/química , Ligação Proteica , Ratos , Receptor Tipo 1 de Angiotensina , Receptor Tipo 2 de Angiotensina , Receptores de Angiotensina/química , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/fisiologia , Relação Estrutura-Atividade , Transfecção , Valina/química
18.
J Biol Chem ; 271(45): 28624-9, 1996 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-8910494

RESUMO

Tumor necrosis factor (TNF) promotes diverse responses in endothelial cells that are important to the host response to infections and malignancies; however, less is known of the postreceptor events important to TNF action in endothelial cells than in many other cell types. Since phosphorylation cascades are implicated in cytokine signaling, the effects of the protein kinase inhibitor dimethylaminopurine (DMAP) on TNF action in bovine aortic endothelial cells (BAEC) were investigated. In BAEC, TNF promotes phosphorylation of eukaryotic initiation factor 4E (eIF-4E), c-Jun N-terminal kinase (JNK) and ceramide-activated protein kinase activities, Jun-b expression, prostacyclin production, and, when protein synthesis is inhibited, cytotoxicity. DMAP abrogated or significantly attenuated each of these responses to TNF, without affecting the specific binding of TNF to its receptors. Histamine, another agent active in the endothelium, promotes phosphorylation of elongation factor-2 (EF-2) and prostacyclin production, but not phosphorylation of eIF-4E in BAEC. Histamine-stimulated EF-2 phosphorylation was not inhibited and prostacyclin production was unaffected by DMAP. These observations demonstrate that a distinct signal transduction cascade, which can be selectively inhibited by DMAP, promotes the response of BAEC to TNF. Thus, we have identified a reagent, DMAP, that may be useful for characterizing the TNF signal transduction pathway.


Assuntos
Adenina/análogos & derivados , Endotélio Vascular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adenina/farmacologia , Animais , Bovinos , Fator de Iniciação 4E em Eucariotos , Histamina/farmacologia , Fator 2 de Elongação de Peptídeos , Fatores de Alongamento de Peptídeos/metabolismo , Fatores de Iniciação de Peptídeos/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-raf
19.
J Biol Chem ; 268(14): 9949-52, 1993 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-7683686

RESUMO

Two distinct receptors, which bind both tumor necrosis factor-alpha and tumor necrosis factor-beta (TNF-alpha and TNF-beta), have been previously identified and cloned from transformed cells. The present study identifies a novel receptor subtype in normal human liver which binds TNF-alpha but not TNF-beta. TNF-alpha but not TNF-beta competes for 125I-TNF-alpha binding and incorporation into affinity-labeled complexes in human liver plasma membranes (HLPM). Antisera to the cloned receptors competed for 125I-TNF-alpha binding to plasma membranes isolated from various transformed cell lines but not to HLPM. However, mRNAs corresponding in size to both known TNF receptors were detected in liver RNA, making it likely that post-transcriptional modifications account for the TNF-alpha specificity of HLPM. These observations suggest that the effects of TNF-alpha and TNF-beta on some normal tissues may be more distinct than previously realized.


Assuntos
Fígado/metabolismo , Receptores de Superfície Celular/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Anticorpos Monoclonais , Complexo Antígeno-Anticorpo , Ligação Competitiva , Northern Blotting , Membrana Celular/metabolismo , Células Cultivadas , Humanos , Cinética , Leucemia Promielocítica Aguda , Linfoma Difuso de Grandes Células B , Peso Molecular , RNA/genética , RNA/isolamento & purificação , RNA Neoplásico/genética , RNA Neoplásico/isolamento & purificação , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/isolamento & purificação , Receptores do Fator de Necrose Tumoral , Proteínas Recombinantes/metabolismo , Células Tumorais Cultivadas
20.
J Biol Chem ; 266(5): 2685-8, 1991 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-1993647

RESUMO

The initiation of mRNA translation is regulated by the reversible phosphorylation of several initiation factors. We report here that tumor necrosis factor-alpha (TNF) rapidly stimulates phosphorylation of one such factor, an mRNA cap binding protein, in several cell types which are important in vitro models of TNF action. This protein has been purified, sequenced, and identified as the proto-oncogene product eukaryotic initiation factor 4E. These data show that phosphorylation of a key component of the cellular translational machinery is a common early event in the various actions of TNF in diverse cell types.


Assuntos
Fatores de Iniciação de Peptídeos/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Sequência de Aminoácidos , Autorradiografia , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de Poliacrilamida , Fator de Iniciação 4E em Eucariotos , Humanos , Dados de Sequência Molecular , Fatores de Iniciação de Peptídeos/genética , Fosforilação , Biossíntese de Proteínas , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas/genética , RNA Mensageiro/genética , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA