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1.
Cell Death Dis ; 4: e710, 2013 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-23828573

RESUMO

Transfer of type-1 helper T-conditioned (Th1-conditioned) cells promotes functional recovery with enhanced axonal remodeling after spinal cord injury (SCI). This study explored the molecular mechanisms underlying the beneficial effects of pro-inflammatory Th1-conditioned cells after SCI. The effect of Th1-conditioned cells from interferon-γ (ifn-γ) knockout mice (ifn-γ(-/-) Th1 cells) on the recovery after SCI was reduced. Transfer of Th1-conditioned cells led to the activation of microglia (MG) and macrophages (MΦs), with interleukin 10 (IL-10) upregulation. This upregulation of IL-10 was reduced when ifn-γ(-/-) Th1 cells were transferred. Intrathecal neutralization of IL-10 in the spinal cord attenuated the effects of Th1-conditioned cells. Further, IL-10 is robustly secreted from Th1-conditioned cells in an ifn-γ-dependent manner. Th1-conditioned cells from interleukin 10 knockout (il-10(-/-)) mice had no effects on recovery from SCI. These findings demonstrate that ifn-γ-dependent secretion of IL-10 from Th1 cells, as well as native MG/MΦs, is required for the promotion of motor recovery after SCI.


Assuntos
Interferon gama/fisiologia , Interleucina-10/metabolismo , Macrófagos/metabolismo , Microglia/metabolismo , Traumatismos da Medula Espinal/terapia , Células Th1/metabolismo , Transferência Adotiva , Animais , Células Cultivadas , Feminino , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Imunoterapia Adotiva , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fatores de Crescimento Neural/metabolismo , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/imunologia , Células Th1/transplante , Regulação para Cima
2.
Cell Death Dis ; 3: e363, 2012 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-22875000

RESUMO

The role of T lymphocytes in central nervous system (CNS) injuries is controversial, with inconsistent results reported concerning the effects of T-lymphocyte transfer on spinal cord injury (SCI). Here, we demonstrate that a specific T-lymphocyte subset enhances functional recovery after contusion SCI in mice. Intraperitoneal adoptive transfer of type 1 helper T (Th1)-conditioned cells 4 days after SCI promoted recovery of locomotor activity and tactile sensation and concomitantly induced regrowth of corticospinal tract and serotonergic fibers. However, neither type 2 helper T (Th2)- nor IL-17-producing helper T (Th17)-conditioned cells had such effects. Activation of microglia and macrophages were observed in the spinal cords of Th1-transfered mice after SCI. Specifically, M2 subtype of microglia/macrophages was upregulated after Th1 cell transfer. Neutralization of interleukin 10 secreted by Th1-conditioned cells significantly attenuated the beneficial effects by Th1-conditioned lymphocytes after SCI. We also found that Th1-conditioned lymphocytes secreted significantly higher levels of neurotrophic factor, neurotrophin 3 (NT-3), than Th2- or Th17-conditioned cells. Thus, adoptive transfer of pro-inflammatory Th1-conditioned cells has neuroprotective effects after SCI, with prospective implications in immunomodulatory treatment of CNS injury.


Assuntos
Transferência Adotiva , Axônios/metabolismo , Traumatismos da Medula Espinal/fisiopatologia , Células Th1/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Interleucina-10/metabolismo , Interleucina-17/metabolismo , Macrófagos/citologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Microglia/citologia , Microglia/metabolismo , Atividade Motora , Neurotrofina 3/metabolismo , Recuperação de Função Fisiológica , Células Th1/imunologia , Células Th1/transplante , Células Th17/imunologia , Células Th17/metabolismo , Células Th17/transplante , Células Th2/imunologia , Células Th2/metabolismo , Células Th2/transplante , Tato
3.
Cytokine ; 36(1-2): 69-74, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17161613

RESUMO

In order to predict the clinical benefit of interferon-beta (IFN-beta) to patients with multiple sclerosis (MS), the following markers were investigated; (1) chronological change of cytokines (IFN-gamma, TNF-alpha, IL-6, IL-10, and TGF-beta) after administration of IFN-beta, (2) untoward effects of IFN-beta such as headache and arthralgia, (3) backgrounds of the patients such as age and relapse rate, (4) efficacy of IFN-beta therapy assessed by the change of relapse rate and progression of disability. Chronological blood sampling was performed 0, 10, and 24 h after injection of IFN-beta. The increase of serum IL-6 level in response to IFN-beta administration was associated with headache, arthralgia, relapse rate before treatment, and disability score at the initiation of the therapy. Significant association of change of serum TNF-alpha with age and headache was also observed. The important finding in this study was that patients with a transient increase in IL-6 in response to IFN-beta showed a slow disease progression. This result suggests that this transient increase in the serum IL-6 predicts favorable response to IFN-beta treatment.


Assuntos
Interferon beta/uso terapêutico , Interleucina-6/sangue , Esclerose Múltipla/sangue , Esclerose Múltipla/tratamento farmacológico , Adulto , Envelhecimento/sangue , Pessoas com Deficiência , Progressão da Doença , Feminino , Humanos , Injeções , Interferon beta/administração & dosagem , Masculino , Esclerose Múltipla/patologia , Fator de Necrose Tumoral alfa/sangue
4.
J Viral Hepat ; 12(2): 130-8, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15720527

RESUMO

Interferon-alpha (IFN-alpha) is widely used in the treatment of chronic hepatitis C (CHC). The suppressor of cytokine signalling (SOCS) family has been implicated in the regulation of JAK-STAT signalling, including IFN signalling. The negative effect of SOCS expression on the response of CHC to IFN-alpha is demonstrated here. The transcriptional levels of SOCS-1 and -3 in the livers of 21 patients with CHC and eight controls were investigated by quantitative reverse transcription-polymerase chain reaction. We established stable transfectants of SOCS-1 in a human hepatoma cell line, PLC/PRF/5 and analysed the effects of SOCS-1 on the phosphorylation of IFN-alpha-induced STAT-1 tyrosine by immunoblotting and the expression of antiviral genes by Northern blot. A prospective cohort study on SOCS-1 expression and clinical outcome was carried out in 77 patients with CHC who received IFN therapy. SOCS-1, but not SOCS-3, transcripts in the livers of CHC were significantly higher than controls (P < 0.005). IFN-alpha-induced STAT-1 phosphorylation and the expression of antiviral genes were inhibited in SOCS-1-transfected cells. Patients showing high SOCS-1 expression in the liver had a significantly lower rate of sustained virological response (SVR) to IFN therapy than those with low SOCS-1 expression (P = 0.0014). A multivariate analysis performed with host factors revealed that SOCS-1 staining in the liver can serve as a significant predictor for IFN SVR (P = 0.004). SOCS-1 expression is enhanced in the livers of CHC patients and might be involved in resistance to IFN therapy.


Assuntos
Farmacorresistência Viral , Hepatite C Crônica/tratamento farmacológico , Hepatócitos/efeitos dos fármacos , Interferon-alfa/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Adulto , Análise de Variância , Northern Blotting , Western Blotting , Células Cultivadas , Estudos de Coortes , Feminino , Regulação da Expressão Gênica , Marcadores Genéticos , Hepatite C Crônica/patologia , Hepatócitos/fisiologia , Humanos , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intracelular/genética , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Estudos Prospectivos , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Estatísticas não Paramétricas
5.
Thorax ; 58(10): 872-5, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14514942

RESUMO

BACKGROUND: The circulating level of KL-6/MUC1 is a sensitive marker for various interstitial lung diseases. Previous case reports have suggested that KL-6 may also be increased in some patients with drug induced pneumonitis. A study was undertaken to determine whether serum KL-6 could be a marker for particular types of drug induced pneumonitis. METHODS: The findings of high resolution computed tomographic (HRCT) chest scans of 30 patients with drug induced pneumonitis were reviewed separately by two independent observers. The pneumonitis was classified into four predominant patterns: widespread bilateral consolidation (diffuse alveolar damage, DAD; n=7), fibrosis with or without consolidation (chronic interstitial pneumonia, CIP; n=11), consolidation without fibrosis (bronchiolitis obliterans organising pneumonia or eosinophilic pneumonia, BOOP/EP; n=8), and diffuse ground glass opacities without fibrosis (hypersensitivity pneumonitis, HP; n=4). Serum KL-6 levels were measured by a sandwich enzyme linked immunosorbent assay. RESULTS: The overall sensitivity of serum KL-6 in detecting drug induced lung disease was 53.3%, which was lower than its sensitivity in detecting other interstitial lung diseases. However, the KL-6 level was increased in most patients with a DAD or CIP pattern (16/18; 88.9%) and was closely correlated with their clinical course. In contrast, serum KL-6 levels were within the normal range in all patients with a BOOP/EP or HP pattern. CONCLUSIONS: Particular patterns detected by HRCT scanning, such as DAD and CIP but not the BOOP/EP or HP patterns, are associated with increased circulating KL-6 levels in drug induced pneumonitis. Serum KL-6 levels may reflect the clinical activity of the particular disorders.


Assuntos
Antígenos/sangue , Glicoproteínas/sangue , Doenças Pulmonares Intersticiais/induzido quimicamente , Pneumonia/induzido quimicamente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Neoplasias , Biomarcadores/sangue , Feminino , Humanos , Doenças Pulmonares Intersticiais/sangue , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Mucina-1 , Mucinas , Variações Dependentes do Observador , Pneumonia/sangue , Pneumonia/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos
6.
Org Lett ; 3(25): 4015-8, 2001 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-11735573

RESUMO

[reaction: see text] An intramolecular enantiodivergent synthesis of both enantiomers of the ABCDE-ring analogue 22 of fredericamycin A is reported. Key steps involve an intramolecular [4 + 2] cycloaddition of 17 and an aromatic Pummerer-type reaction of 19. A lipase-catalyzed enantioselective desymmetrization of prochiral diol 2 using 1-ethoxyvinyl 2-furoate 3 led to the pivotal intermediate (R)-4.


Assuntos
Antibióticos Antineoplásicos/química , Isoquinolinas/química , Compostos de Espiro/química , Antibióticos Antineoplásicos/síntese química , Candida/enzimologia , Dicroísmo Circular , Humanos , Isoquinolinas/síntese química , Lipase/metabolismo , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Compostos de Espiro/síntese química , Estereoisomerismo
7.
J Clin Pathol ; 54(12): 945-50, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11729215

RESUMO

AIMS: The epithelioid features seen in chordoma are unique among mesenchymal tumours. However, no detailed analysis regarding cell-cell communication has been conducted in this epithelioid tumour. The aims of this study were to investigate cell-cell communication in chordoma. METHODS: By means of immunohistochemical techniques that incorporated a panel of monoclonal antibodies against cell adhesion molecules (CAMs), including E-cadherin, alpha-catenin, beta-catenin, gamma-catenin, and neural cell adhesion molecule (NCAM), the expression of CAMs was studied in 15 specimens of chordoma and eight specimens of chondrosarcoma. RESULTS: Most chordoma specimens showed some positive immunoreactivity for all the CAMs examined. For the various CAMs investigated, between two and five cases showed diffuse immunoreactions, indicating well preserved expression. Well preserved expression of all the CAMs examined was limited to only one case, thus indicating that the expression of CAMs was decreased in most of the chordoma specimens; however, no significant correlation was found between the decreased expression of CAMs and the histological grade of malignancy, cellular growth pattern, or clinical parameters in chordoma. In chondrosarcoma, only a few specimens showed positive immunoreactivity for CAMs and the expression of E-cadherin, beta-catenin, gamma-catenin, and NCAM was seen more frequently in the chordoma specimens than in the chondrosarcoma specimens. CONCLUSIONS: These results suggest that the expression of CAMs is associated with the formation and maintenance of chordoma tissue architecture, just as it is in other epithelial tumours or normal tissue. Immunohistochemistry for CAMs was found to be of diagnostic value for discriminating chordoma from chondrosarcoma, and these markers could be used along with the cytokeratins, which are already used for this purpose.


Assuntos
Neoplasias Ósseas/química , Moléculas de Adesão Celular/análise , Cordoma/química , Transativadores , Adulto , Idoso , Biomarcadores Tumorais/análise , Caderinas/análise , Condrossarcoma/química , Proteínas do Citoesqueleto/análise , Desmoplaquinas , Diagnóstico Diferencial , Feminino , Humanos , Imuno-Histoquímica/métodos , Masculino , Pessoa de Meia-Idade , Moléculas de Adesão de Célula Nervosa/análise , alfa Catenina , beta Catenina , gama Catenina
8.
Surg Today ; 31(9): 774-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11686554

RESUMO

We evaluated postoperative function in 98 patients who underwent surgery for early gastric cancer between 1995 and 1998 to compare the results of pylorus-preserving procedures to those of conventional distal gastrectomy with Billroth I (B-I). The pylorus-preserving procedures included endoscopic mucosal resection (EMR), performed in 12 patients; local resection (Local), performed in 14 patients; segmental resection (Seg), performed in 8 patients; and pylorus-preserving gastrectomy (PPG), performed in 19 patients. B-I was performed in 45 patients. The nutritional status and serum albumin (Alb) levels after PPG, the hemoglobin (Hb) levels after EMR, Local, and PPG, and the present/preoperative body weight ratios after EMR, Local, Seg, and PPG were superior to those after B-I. The time before oral intake was recommenced after EMR and Local, the volume of oral intake tolerated after EMR, Local, Seg, and PPG, and the postoperative hospital stay after EMR were all superior to those after B-I. Moreover, significantly fewer patients suffered reflux symptoms after EMR, Local, and PPG, abdominal fullness after EMR, and early dumping syndrome after EMR, Local, and PPG than after B-I. There was also less evidence of gastritis after EMR, Local, and PPG, and of bile reflux after EMR, Local, and PPG, than after B-I. These findings indicate that pylorus-preserving procedures may result in a better postoperative quality of life for selected patients with early gastric cancer.


Assuntos
Gastrectomia/métodos , Neoplasias Gástricas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Gastroscopia , Humanos , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Período Pós-Operatório , Qualidade de Vida , Resultado do Tratamento
9.
J Med Chem ; 44(15): 2438-50, 2001 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-11448226

RESUMO

A series of 2-oxopiperazine derivatives, possessing basic moieties at the 3- and the 4-positions, were synthesized and evaluated for their abilities to inhibit platelet aggregation and for their effects on bleeding time. Among the compounds, 2-[(3S)-4-[2-[(4-guanidinobenzoyl)amino]acetyl]-3-[3-[(4-guanidinobenzoyl)amino]propyl]-2-oxopiperazinyl]acetic acid (12c) showed a potent inhibitory effect on platelet aggregation and good dissociation between the efficacy and the bleeding side effect. Intravenous infusion of compound 12c at 1.6 microg/mL/min completely prevented arterial thrombus formation induced by endothelial injury in guinea pigs. The dose of 12c that prolonged the bleeding time to three times the control value was 5.8 microg/mL/min. These results suggest that compound 12c might be useful in the clinical treatment of thrombotic diseases, and we selected 12c (TAK-024) as a candidate for the clinical trials.


Assuntos
Fibrinolíticos/síntese química , Guanidinas/síntese química , Piperazinas/síntese química , Inibidores da Agregação Plaquetária/síntese química , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Difosfato de Adenosina/farmacologia , Animais , Tempo de Sangramento , Trombose das Artérias Carótidas/tratamento farmacológico , Trombose das Artérias Carótidas/etiologia , Cateterismo , Avaliação Pré-Clínica de Medicamentos , Fibrinolíticos/química , Fibrinolíticos/farmacologia , Guanidinas/química , Guanidinas/farmacologia , Cobaias , Humanos , Técnicas In Vitro , Macaca fascicularis , Masculino , Piperazinas/química , Piperazinas/farmacologia , Inibidores da Agregação Plaquetária/química , Inibidores da Agregação Plaquetária/farmacologia , Relação Estrutura-Atividade
10.
Curr Microbiol ; 42(6): 398-402, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11381330

RESUMO

The mutation of Agrobacterium radiobacter cells exposed to chrysotile asbestos was examined by the random amplified polymorphic DNA (RAPD) method. Approximately 1.4 kbp of DNA in A. radiobacter, which was not amplified strongly in the cells that were not exposed to asbestos, was amplified in the cells that were exposed to asbestos. Mutation in genomic DNA of A. radiobacter was found to be induced by asbestos. Specific DNA that was amplified by asbestos present in PCR products and that which exists latently in genomic DNA were cloned, and these sequences were then determined and compared. It was shown that one of the mutations by the asbestos in the A. radiobacter occurred only in the primer annealed region and was a point mutation or deletion.


Assuntos
Asbestos Serpentinas/toxicidade , Mutagênicos/toxicidade , Rhizobium/efeitos dos fármacos , Sequência de Bases , Clonagem Molecular , Análise Mutacional de DNA , DNA Bacteriano , Mutação em Linhagem Germinativa , Dados de Sequência Molecular , Testes de Mutagenicidade , Mutação Puntual , Reação em Cadeia da Polimerase , Técnica de Amplificação ao Acaso de DNA Polimórfico , Deleção de Sequência
11.
Int J Syst Evol Microbiol ; 51(Pt 2): 281-292, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11321072

RESUMO

A polyphasic taxonomic study was performed on Sphingomonas sp. strain RW1T. The organism was isolated from water of the River Elbe and has been known as a potent metabolizer of dibenzo-p-dioxin and its relatives. TLC of a mild alkaline hydrolysate of extractable cellular lipids of strain RW1T and type strains of 21 Sphingomonas species gave a spot of sphingoglycolipid (SGL)-1 (glucuronosyl ceramide), which is characteristic of sphingomonads. In addition, strain RW1T and type strains of three Sphingomonas species (Sphingomonas yanoikuyae, Sphingomonas terrae and Sphingomonas macrogoltabidus) showed a second spot of SGL (SGL-1') identified as galacturonosyl ceramide. The presence of SGL-1 in cellular lipids suggested that strain RW1T is a member of the genus Sphingomonas. DNA-DNA reassociation rates between strain RW1T and each type strain of 14 Sphingomonas species including Sphingomonas paucimobilis, type species for the genus, revealed that strain RW1T is independent from these species. Results of phylogenetic analysis of 16S rDNA sequences of strain RW1T and type strains of 21 named Sphingomonas species verified that strain RW1T belongs to the genus Sphingomonas. Strain RW1T could be differentiated from named species of the genus by phenotypic characteristics and has been assigned to a new species, Sphingomonas wittichii sp. nov. The type strain is DSM 6014T (= JCM 10273T = EY 4224T). DNA G+C content is 67 mol %.


Assuntos
Dioxinas/metabolismo , Sphingomonas/classificação , Sphingomonas/metabolismo , Microbiologia da Água , Técnicas de Tipagem Bacteriana , Ceramidas/isolamento & purificação , DNA Bacteriano , DNA Ribossômico/genética , Ácidos Graxos Ômega-3 , Água Doce , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Fenótipo , RNA Ribossômico 16S/genética , Sphingomonas/ultraestrutura , Terminologia como Assunto
12.
Surg Today ; 31(4): 346-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11321347

RESUMO

We report herein the case of a 70-year-old woman found to have a gastrointestinal stromal tumor (GIST) of the stomach. Preoperative X-ray and endoscopic examination revealed a hemispheric submucosal tumor with central depression in the anterior wall of the gastric fornix. The tumor, which was 3 cm in diameter, was resected by a laparoscopy-assisted procedure. Histologic examination revealed that it was composed of spindle-shaped cells with elongated nuclei, and few mitoses. Most of the tumor cells showed immunoreactivity for vimentin and CD34, but not for alpha-smooth muscle actin, desmin, or S-100 protein. The PCNA index was 40.5%. Thus, the GIST did not show differentiation toward smooth muscle or neural cells. A gastrectomy was not performed because the small size of the tumor, and the paucity of the mitoses indicated that it was benign. Nevertheless, careful and long-term follow-up is needed to monitor for signs of possible local recurrence or distant metastases.


Assuntos
Laparoscopia , Neoplasias Gástricas/cirurgia , Idoso , Biomarcadores Tumorais/análise , Diagnóstico Diferencial , Feminino , Humanos , Prognóstico , Estômago/patologia , Estômago/cirurgia , Neoplasias Gástricas/patologia
13.
Chem Pharm Bull (Tokyo) ; 49(3): 258-67, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11253914

RESUMO

To improve the in vitro and in vivo potency of our first low molecular weight GPIIb/IIIa antagonist 1 (TAK-029), a series of 2-[4-[2-(4-amidinobenzoylamino)-2-(substituted)acetyl]-3-(2-methoxy-2-oxoethyl)-2-oxopiper-azinyllacetic acids were synthesized through modification of the glycine moiety of 1 and evaluated for their ability to inhibit in vitro adenosine 5'-diphosphate (ADP)-induced platelet aggregation of guinea pig platelet rich plasma (PRP). Among the compounds examined, the (3S,2S)-4-methoxyphenylalanine derivative 4h showed the most potent antagonistic activity with an IC50 value of 13 nM. Dose-dependent inhibition of ex vivo platelet aggregation was achieved with oral administration of 4h (0.3-1.0 mg/kg) to guinea pigs. Complete inhibition was observed for up to 8 h, and 43% inhibition could still be observed 24 h after oral administration of 1.0 mg/kg. The long-lasting antiplatelet effect of 4h suggests that 4h would be suitable for once-a-day dosing. Structure-activity relationships (SAR) were examined in the series of the phenylalanine derivatives. An increase in the electron density around the 4-position of the phenyl ring of the phenylalanine moiety led to an increase in the antiplatelet activity, suggesting the existence of a hydrophobic and electrostatic interaction site in addition to the ionic binding sites in the GPIIb/IIIa.


Assuntos
Acetatos/síntese química , Acetatos/farmacologia , Piperazinas/síntese química , Piperazinas/farmacologia , Inibidores da Agregação Plaquetária/síntese química , Inibidores da Agregação Plaquetária/farmacologia , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Aminoácidos/química , Animais , Sítios de Ligação , Fibrinogênio/metabolismo , Cobaias , Humanos , Técnicas In Vitro , Indicadores e Reagentes , Macaca fascicularis , Modelos Químicos , Conformação Molecular , Agregação Plaquetária/efeitos dos fármacos , Estereoisomerismo , Relação Estrutura-Atividade
14.
Chem Pharm Bull (Tokyo) ; 49(3): 268-77, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11253915

RESUMO

To improve the in vivo potency of the potent GPIIb/IIIa antagonist 2-[(3S)-4-[(2S)-2-(4-amidinobenzoylamino)-3-(4-methoxyphenyl)propanoyl]-3-(2-methoxy-2-oxoethyl)-2-oxopiperazinyljacetic acid (4), the amidino group was converted to an oxadiazole ring, thiadiazole ring or substituted amidoxime group. These groups were expected to be metabolized to an amidino group in vivo. The compounds synthesized were evaluated for their potency to inhibit the ex vivo adenosine 5'-diphosphate (ADP)-induced aggregation of guinea pig platelets. Among the compounds examined, the methoxycarbonyloxyamidine 8a exhibited the most potent ex vivo inhibitory activity with a fast onset and prolonged duration of action after oral administration.


Assuntos
Acetatos/síntese química , Acetatos/farmacologia , Piperazinas/síntese química , Piperazinas/farmacologia , Inibidores da Agregação Plaquetária/síntese química , Inibidores da Agregação Plaquetária/farmacologia , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Pró-Fármacos/síntese química , Pró-Fármacos/farmacologia , Acetatos/farmacocinética , Aminoácidos/química , Animais , Sítios de Ligação , Cobaias , Técnicas In Vitro , Indicadores e Reagentes , Masculino , Conformação Molecular , Piperazinas/farmacocinética , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacocinética , Relação Estrutura-Atividade
15.
Microb Pathog ; 30(2): 91-9, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11162189

RESUMO

Novel mycoloyl glycolipids with short carbon chains were isolated and purified from Rhodococcus sp. 4306, a soil origin of Actinomycetales. Their chemical structures were identified as trehalose 6,6'-dimycolate (TDM), trehalose 6-monomycolate, glucose 6-monomycolate, mannose 6-monomycolate and fructose 6-monomycolate. The length of carbon chains and number of double bonds of mycolic acids were C(34), C(36)and C(38)saturated, monoenoic and dienoic molecular species, which were much shorter than those of Mycobacterium tuberculosis (C(78-88)monoenoic and dienoic). Among them, only TDM could induce prominent granulomatous inflammation of the lung and spleen in mice. By contrast, other mycoloyl glycolipids induced mild lesions. The small-sized TDM of Rhodococcus possessed granulomatogenic activity, however, the toxicity was much lower than that of M. tuberculosis. Rhodococcal TDM was composed of mycolic acid with the shortest carbon chains, when compared to granulomatogenic TDM of Mycobacterium, Nocardia and Rhodococcus reported previously. Our results imply that rhodococcal TDM is a pathogenetic factor similar to that of M. tuberculosis, although rhodococcal TDM exhibits low toxicity.


Assuntos
Infecções por Actinomycetales/microbiologia , Infecções por Actinomycetales/fisiopatologia , Fatores Corda/química , Fatores Corda/metabolismo , Rhodococcus/patogenicidade , Trealose/análogos & derivados , Animais , Cromatografia em Camada Fina , Fatores Corda/administração & dosagem , Granuloma/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Mycobacterium tuberculosis/metabolismo , Rhodococcus/metabolismo , Relação Estrutura-Atividade , Trealose/administração & dosagem , Trealose/química , Trealose/metabolismo
16.
J Immunol ; 165(4): 1799-806, 2000 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10925257

RESUMO

Previous experiments have shown that STAT-induced STAT inhibitor-1 (SSI-1; also named suppressors of cytokine signaling-1 (SOCS-1) or Janus kinase binding protein) is predominantly expressed in lymphoid organs and functions in vitro as a negative regulator of cytokine signaling. To determine the function of SOCS-1 in vivo, we generated SSI-1 transgenic mice using the lck proximal promoter that drives transgene expression in T cell lineage. In thymocytes expressing SSI-1 transgene, tyrosine phosphorylation of STATs in response to cytokines such as IFN-gamma, IL-6, and IL-7 was inhibited, suggesting that SSI-1 suppresses cytokine signaling in primary lymphocytes. In addition, lck-SSI-1 transgenic mice showed a reduction in the number of thymocytes as a result of the developmental blocking during triple-negative stage. They also exhibited a relative increase in the percentage of CD4+ T cells, a reduction in the number of gammadelta T cells, as well as the spontaneous activation and increased apoptosis of peripheral T cells. Thus, enforced expression of SSI-1 disturbs the development of thymocytes and the homeostasis of peripheral T cells. All these features of lck-SSI-1 transgenic mice strikingly resemble the phenotype of mice lacking common gamma-chain or Janus kinase-3, suggesting that transgene-derived SSI-1 inhibits the functions of common gamma-chain-using cytokines. Taken together, these results suggest that SSI-1 can also inhibit a wide variety of cytokines in vivo.


Assuntos
Proteínas de Transporte/genética , Citocinas/antagonistas & inibidores , Homeostase/imunologia , Linfopenia/genética , Linfopenia/imunologia , Proteínas Repressoras , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Linfócitos T/patologia , Animais , Apoptose/genética , Apoptose/imunologia , Proteínas de Transporte/fisiologia , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Citocinas/deficiência , Citocinas/genética , Feminino , Homeostase/genética , Memória Imunológica/genética , Imunofenotipagem , Janus Quinase 3 , Ativação Linfocitária/genética , Contagem de Linfócitos , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/genética , Linfopenia/patologia , Camundongos , Camundongos Transgênicos , Gravidez , Proteínas Tirosina Quinases/deficiência , Proteínas Tirosina Quinases/genética , Receptores de Citocinas/deficiência , Receptores de Citocinas/genética , Proteína 1 Supressora da Sinalização de Citocina , Proteínas Supressoras da Sinalização de Citocina , Linfócitos T/enzimologia , Linfócitos T/imunologia , Linfócitos T/metabolismo
17.
Hum Pathol ; 31(6): 709-16, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10872665

RESUMO

Changes in morphological features between the primary and metastatic sites in osteosarcoma and the role of nm23 protein and c-MET oncogene product have remained controversial. In addition to histological studies, we evaluated the expression of nm23, c-MET, p53, and MDM2 immunohistochemically using 25 osteosarcomas in which both primary and concordant metastatic specimens were available. Moreover, we assessed proliferative activity using the monoclonal antibody MIB-1. Among these 25 cases, 4 tumors that were osteoblastic type (16%) in the primary site had changed morphologically to MFH-like type in the metastatic site, whereas 2 MFH-like type and 1 small cell-type tumors had changed to osteoblastic type. MIB-1 LI was significantly higher in the metastatic site than in the primary site (primary, 20.02; metastatic, 26.72; P = .0209). Seventeen cases (68%) showed increased nm23 expression in the metastatic site, whereas 2 cases showed reduced expression. nm23 expression was significantly increased in the metastatic site, compared with the primary site (P = .0009). Seven cases (28%) showing negative reaction for c-MET in the primary site showed immunuoreactivity for c-MET in the metastatic site. Although there was no statistical significance, c-MET expression seemed to be more frequent in the metastatic site, compared with the primary site. Among the overall tumors, c-MET-positive tumors showed significantly higher MIB-1 LI, compared with c-MET-negative tumors (negative, 20.99; positive, 27.65; P = .0292). No significant change was observed regarding p53 and MDM2 between the primary and metastatic site. Our results suggest that rather than being a metastasis-suppressor gene, nm23 is in fact correlated with metastatic progression in osteosarcoma. Positive correlation between c-MET expression and proliferative activity also suggests that c-MET expression may play an important role in tumor progression in osteosarcomas.


Assuntos
Neoplasias Ósseas/patologia , Neoplasias Pulmonares/secundário , Proteínas Monoméricas de Ligação ao GTP/análise , Núcleosídeo-Difosfato Quinase , Osteossarcoma/patologia , Osteossarcoma/secundário , Proteínas Proto-Oncogênicas c-met/análise , Fatores de Transcrição/análise , Adolescente , Adulto , Idoso , Anticorpos Monoclonais , Antígenos de Neoplasias/análise , Neoplasias Ósseas/química , Divisão Celular , Criança , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/química , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Nucleosídeo NM23 Difosfato Quinases , Osteoblastos/patologia , Osteossarcoma/química
18.
Proc Natl Acad Sci U S A ; 97(10): 5405-10, 2000 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-10792035

RESUMO

Signal transducers and activators of transcription (STAT)-induced STAT inhibitor-1 [SSI-1; also known as suppressor of cytokine signaling-1 (SOCS-1)] was identified as a negative feedback regulator of Janus kinase-STAT signaling. We previously generated mice lacking the SSI-1 gene (SSI-1 -/-) and showed that thymocytes and splenocytes in SSI-1 -/- mice underwent accelerated apoptosis. In this paper, we show that murine embryonic fibroblasts lacking the SSI-1 gene are more sensitive than their littermate controls to tumor necrosis factor-alpha (TNF-alpha)-induced cell death. In addition, L929 cells forced to express SSI-1 (L929/SSI-1), but not SSI-3 or SOCS-5, are resistant to TNF-alpha-induced cell death. Furthermore L929/SSI-1 cells treated with TNF-alpha sustain the activation of p38 mitogen-activated protein (MAP) kinase. In contrast, SSI-1 -/- murine embryonic fibroblasts treated with TNF-alpha show hardly any activation of p38 MAP kinase. These findings suggest that SSI-1 suppresses TNF-alpha-induced cell death, which is mediated by p38 MAP kinase signaling.


Assuntos
Proteínas de Transporte/fisiologia , Morte Celular/fisiologia , Citocinas/farmacologia , Proteínas de Ligação a DNA/metabolismo , Inibidores Enzimáticos/metabolismo , Fibroblastos/fisiologia , Proteínas Repressoras , Transativadores/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Fator de Necrose Tumoral alfa/fisiologia , Androstadienos/farmacologia , Animais , Proteínas de Transporte/genética , Caspase 3 , Inibidores de Caspase , Caspases/metabolismo , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Embrião de Mamíferos , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Imidazóis/farmacologia , Interferon gama/farmacologia , Interleucina-1/farmacologia , Cinética , Células L , Camundongos , Camundongos Knockout , Piridinas/farmacologia , Proteínas Recombinantes/farmacologia , Fator de Transcrição STAT1 , Transdução de Sinais , Proteína 1 Supressora da Sinalização de Citocina , Proteínas Supressoras da Sinalização de Citocina , Transativadores/deficiência , Transativadores/genética , Transfecção , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Wortmanina
19.
J Immunol ; 164(11): 5833-43, 2000 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-10820262

RESUMO

STAT-induced STAT inhibitor-1 (SSI-1), also referred to as suppressor of cytokine signaling-1 and JAK-binding protein, is a member of a new family, the members of which are negative regulators of cytokine signals. SSI-1 is induced by various cytokines; however, the transcriptional mechanism of the SSI-1 gene is not fully understood. Here, we showed that transcription of the mouse SSI-1 gene was initiated from six adjoining sites accompanying three GC boxes and a single GC box-like element near them, but not from the TATA box or an initiator sequence. We also showed that IFN-gamma induced SSI-1 mRNA more strongly than IL-6 in NIH-3T3 fibroblasts and that this IFN-gamma effect was mediated by Stat1. To determine the signal pathway downstream of Stat1, transcriptional activities of several mutant promoters were examined. The region mediating stimulatory effect of IFN-gamma to the gene transcription was localized to the -88/-60 region containing three tandem GAAA units, named variant IFN-gamma-responsive element (VIRE), while four IFN-gamma activation site (GAS)-like elements located far upstream were not related to the IFN-gamma response. Gel-shift assays revealed that IFN-gamma induced IFN regulatory factor-1 (IRF-1) binding to VIRE, but not that of IRF-2 or three components of ISGF3. Furthermore, forced expression of IRF-1 mimicked and that of IRF-2 inhibited the stimulatory effect of IFN-gamma on SSI-1 gene transcription. Finally, mouse embryonal fibroblasts lacking IRF-1 showed impaired SSI-1 mRNA induction by IFN-gamma. These results demonstrated that IRF-1, which is induced by activation of Stat1, mediated transcriptional activation of the SSI-1 gene by IFN-gamma via VIRE.


Assuntos
Proteínas de Transporte/genética , Proteínas de Ligação a DNA/fisiologia , Interferon gama/fisiologia , Fosfoproteínas/fisiologia , Regiões Promotoras Genéticas/imunologia , Proteínas Repressoras , Transdução de Sinais/imunologia , Transativadores/fisiologia , Células 3T3/metabolismo , Animais , Sequência de Bases , Proteínas de Transporte/biossíntese , Proteínas de Transporte/química , Proteínas de Transporte/metabolismo , Citocinas/farmacologia , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Sinergismo Farmacológico , Eletroforese em Gel de Poliacrilamida , Fibroblastos/metabolismo , Substâncias de Crescimento/farmacologia , Fator Regulador 1 de Interferon , Camundongos , Dados de Sequência Molecular , Fosfoproteínas/deficiência , Fosfoproteínas/genética , RNA Mensageiro/biossíntese , Elementos de Resposta/imunologia , Transdução de Sinais/genética , Proteína 1 Supressora da Sinalização de Citocina , Proteínas Supressoras da Sinalização de Citocina , Sequências de Repetição em Tandem/imunologia , Transcrição Gênica/imunologia , Fator de Necrose Tumoral alfa/fisiologia
20.
Methods Mol Med ; 45: 167-73, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-21341055

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common human malignancies in the world and it is especially prevalent in Asia and Africa (1). Some tumors are suitable for resection, however, there is a very high rate of recurrence (2). Infection with hepatitis B or C virus, alcoholic cirrhosis, and ingestion of aflatoxin B1-contaminated food are important risk factors for HCC (3,4), but the exact molecular mechanism of tumorigenesis is still unclear.

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