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1.
Ann Oncol ; 28(3): 611-621, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-27993792

RESUMO

Background: All-trans-retinoic acid (ATRA) is a differentiating agent used in the treatment of acute-promyelocytic-leukemia (APL) and it is under-exploited in other malignancies despite its low systemic toxicity. A rational/personalized use of ATRA requires the development of predictive tools allowing identification of sensitive cancer types and responsive individuals. Materials and methods: RNA-sequencing data for 10 080 patients and 33 different tumor types were derived from the TCGA and Leucegene datasets and completely re-processed. The study was carried out using machine learning methods and network analysis. Results: We profiled a large panel of breast-cancer cell-lines for in vitro sensitivity to ATRA and exploited the associated basal gene-expression data to initially generate a model predicting ATRA-sensitivity in this disease. Starting from these results and using a network-guided approach, we developed a generalized model (ATRA-21) whose validity extends to tumor types other than breast cancer. ATRA-21 predictions correlate with experimentally determined sensitivity in a large panel of cell-lines representative of numerous tumor types. In patients, ATRA-21 correctly identifies APL as the most sensitive acute-myelogenous-leukemia subtype and indicates that uveal-melanoma and low-grade glioma are top-ranking diseases as for average predicted responsiveness to ATRA. There is a consistent number of tumor types for which higher ATRA-21 predictions are associated with better outcomes. Conclusions: In summary, we generated a tumor-type independent ATRA-sensitivity predictor which consists of a restricted number of genes and has the potential to be applied in the clinics. Identification of the tumor types that are likely to be generally sensitive to the action of ATRA paves the way to the design of clinical studies in the context of these diseases. In addition, ATRA-21 may represent an important diagnostic tool for the selection of individual patients who may benefit from ATRA-based therapeutic strategies also in tumors characterized by lower average sensitivity.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Leucemia Promielocítica Aguda/tratamento farmacológico , Leucemia Promielocítica Aguda/genética , Tretinoína/uso terapêutico , Neoplasias da Mama/patologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular Tumoral , Feminino , Regulação Leucêmica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Glioma/tratamento farmacológico , Glioma/genética , Glioma/patologia , Humanos , Leucemia Promielocítica Aguda/patologia , Aprendizado de Máquina , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/patologia , Modelos Teóricos , Análise de Sequência de RNA , Neoplasias Uveais/tratamento farmacológico , Neoplasias Uveais/genética , Neoplasias Uveais/patologia
2.
J Viral Hepat ; 24(8): 672-678, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28199034

RESUMO

Hepatitis B surface antigen (HBsAg) reduction during nucleoside/nucleotide analogue (NA) therapy is slow and an alternative strategy for patients receiving ongoing NA to facilitate HBsAg reduction is required. We investigated whether switching to pegylated interferon (PEG-IFN) after long-term NA administration enhances HBsAg reduction. Forty-nine patients who switched from long-term NA to 48 weeks of PEG-IFN alfa-2a were studied. The mean duration of previous NA was 48 months (sequential group). A total of 147 patients who continued NA and matched for baseline characteristics were analysed for comparison (NA continuation group). The treatment response was defined as HBsAg reduction ≥1.0 logIU/mL at the end of PEG-IFN. HBsAg reduction at week 48 was 0.81±1.1 logIU/mL in the sequential group, which was significantly higher than that in the NA continuation group (0.11±0.3 logIU/mL, P < .001). The treatment response was achieved in 29% and 2% of the sequential group and NA continuation group (P < .001), and the odds ratio of sequential therapy for the treatment response was 19 compared with the NA continuation (P < .001). In patients tested positive for hepatitis B e antigen (HBeAg), HBeAg seroconversion was higher in the sequential group (44% vs 8%, P < .001). In HBeAg-negative patients, only patients in the sequential group achieved HBsAg loss. No patient needed to resume NA administration because of HBV DNA increase accompanied by alanine aminotransferase flares. In summary, sequential therapy with PEG-IFN after long-term NA enhances the reduction of HBsAg and may represent a treatment option to promote HBsAg loss.


Assuntos
Antivirais/administração & dosagem , Substituição de Medicamentos/métodos , Antígenos de Superfície da Hepatite B/sangue , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/administração & dosagem , Nucleosídeos/administração & dosagem , Nucleotídeos/administração & dosagem , Polietilenoglicóis/administração & dosagem , Adulto , Idoso , Estudos de Casos e Controles , DNA Viral/sangue , Feminino , Antígenos E da Hepatite B/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/administração & dosagem , Estudos Retrospectivos , Resultado do Tratamento
3.
Ann Oncol ; 26(10): 2066-72, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26153496

RESUMO

BACKGROUND: A previous randomized phase II study demonstrated that the addition of a c-Met inhibitor tivantinib to an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor erlotinib might prolong progression-free survival (PFS) in patients with previously treated, nonsquamous nonsmall-cell lung cancer (NSCLC). On a subset analysis, the survival benefit was greater in patients with wild-type EGFR (WT-EGFR) than in those with activating EGFR mutations. Herein, this phase III study compared overall survival (OS) between Asian nonsquamous NSCLC patients with WT-EGFR who received erlotinib plus tivantinib (tivantinib group) or erlotinib plus placebo (placebo group). METHODS: A total of 460 NSCLC patients were planned to be randomized to the tivantinib or placebo group. Primary end point was OS. Secondary end points were PFS, tumor response, and safety. Tissue was collected for biomarker analysis, including c-Met and HGF expression. RESULTS: Enrollment was stopped when 307 patients were randomized, following the Safety Review Committee's recommendation based on an imbalance in the interstitial lung disease (ILD) incidence between the groups. ILD developed in 14 patients (3 deaths) and 6 patients (0 deaths) in the tivantinib and the placebo groups, respectively. In the enrolled patients, median OS was 12.7 and 11.1 months in the tivantinib and the placebo groups, respectively [hazard ratio (HR) = 0.891, P = 0.427]. Median PFS was 2.9 and 2.0 months in the tivantinib and the placebo groups, respectively (HR = 0.719, P = 0.019). The commonly observed grade ≥ 3 adverse events in the tivantinib group were neutropenia (24.3%), leukopenia (18.4%), febrile neutropenia (13.8%), and anemia (13.2%). CONCLUSIONS: This study was prematurely terminated due to the increased ILD incidence in the tivantinib group. Although this study lacked statistical power because of the premature termination and did not demonstrate an improvement in OS, our results suggest that tivantinib plus erlotinib might improve PFS than erlotinib alone in nonsquamous NSCLC patients with WT-EGFR. TRIAL REGISTRATION NUMBER: NCT01377376.


Assuntos
Adenocarcinoma/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Receptores ErbB/metabolismo , Cloridrato de Erlotinib/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Pirrolidinonas/uso terapêutico , Quinolinas/uso terapêutico , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Taxa de Sobrevida
4.
Tissue Antigens ; 86(6): 406-12, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26449183

RESUMO

Significant associations of HLA-DP alleles with chronic hepatitis B (CHB) infection are evident in Asian and Arabian populations, including Japanese, Han Chinese, Korean, and Saudi Arabian populations. Here, significant associations between CHB infection and five DPB1 alleles (two susceptibility alleles, DPB1(*) 05:01 and (*) 09:01, and three protective alleles, DPB1(*) 02:01, (*) 04:01, and (*) 04:02) were confirmed in a population comprising of 2582 Japanese individuals. Furthermore, odds ratios for CHB were higher for those with both DPB1 susceptibility alleles than for those with only one susceptibility allele; therefore, effects of susceptibility alleles were additive for risk of CHB infection. Similarly, protective alleles showed an additive effect on protection from CHB infection. Moreover, heterozygotes of any protective allele showed stronger association with CHB than did homozygotes, suggesting that heterozygotes may bind a greater variety of hepatitis B-derived peptides, and thus present these peptides more efficiently to T-cell receptors than homozygotes. Notably, compound heterozygote of the protective allele (any one of DPB1*02:01, *04:01, and *04:02) and the susceptible allele DPB1*05:01 was significantly associated with protection against CHB infection, which indicates that one protective HLA-DPB1 molecule can provide dominant protection. Identification of the HLA-DPB1 genotypes associated with susceptibility to and protection from CHB infection is essential for future analysis of the mechanisms responsible for immune recognition of hepatitis B virus antigens by HLA-DPB1 molecules.


Assuntos
Cadeias beta de HLA-DP/genética , Hepatite B Crônica/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Povo Asiático/genética , Portador Sadio/epidemiologia , Portador Sadio/imunologia , Criança , Progressão da Doença , Feminino , Frequência do Gene , Genes MHC da Classe II , Predisposição Genética para Doença , Genótipo , Hepatite B Crônica/epidemiologia , Hepatite B Crônica/imunologia , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
5.
J Viral Hepat ; 21(7): 466-74, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24750345

RESUMO

Inosine triphosphatase (ITPA) genetic variants are strongly associated with ribavirin (RBV)-induced anaemia during pegylated interferon (PEG-IFN) plus RBV therapy. However, the treatment efficacy of ITPA genetic variants has not been fully explored. We enrolled 309 individuals infected with hepatitis C virus genotype 1, who were treated with PEG-IFN plus RBV for 48 weeks. The ITPA SNP: rs1127354 and IL28B SNP: rs8099917 were genotyped. We examined the risk factors for severe anaemia up to week 12 after the start of treatment and treatment efficacy. The incidence of severe anaemia, ≥ 3 g/dL reduction or <10 g/dL of haemoglobin (Hb) up to week 12, was more frequent in patients with CC at rs1127354 [65% (145/224), 33% (73/224)] than in those with CA/AA [25% (21/85), 6% (8/85)] (P < 0.0001). ITPA genotype, pretreatment Hb level and age were independent predictive factors for severe anaemia: Hb < 10 g/dL. In IL28B favourable type, the sustained virologic response rate was higher in ≥ 60-year-old patients with CA/AA than in those with CC [71% (22/31) vs 40% (26/65), P = 0.005], although there was no significant difference in treatment efficacy according to ITPA genetic variants in the <60-year-old patients. The proportion of patients administered ≥ 80% of the dosage of RBV was significantly higher in the patients with CA/AA than in those with CC (P = 0.025), resulting in a lower relapse rate. In conclusion, ITPA genetic variants were associated with severe RBV-induced anaemia and could influence the efficacy of PEG-IFN plus RBV treatment among elderly patients with IL28B favourable type.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/classificação , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Interleucinas/genética , Pirofosfatases/genética , Ribavirina/uso terapêutico , Adulto , Idoso , Anemia/induzido quimicamente , Anemia/epidemiologia , Antivirais/efeitos adversos , Feminino , Genótipo , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Humanos , Interferon-alfa/efeitos adversos , Interferons , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , RNA Viral/sangue , Recidiva , Ribavirina/efeitos adversos , Resultado do Tratamento , Carga Viral
6.
J Viral Hepat ; 20(1): 72-6, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23231087

RESUMO

The FIB-4 index is a simple formula to predict liver fibrosis based on the standard biochemical values (AST, ALT and platelet count) and age. We here investigated the utility of the index for noninvasive prediction of progression in liver fibrosis. The time-course alteration in the liver fibrosis stage between paired liver biopsies and the FIB-4 index was examined in 314 patients with chronic hepatitis C. The average interval between liver biopsies was 4.9 years. The cases that showed a time-course improvement in the fibrosis stage exhibited a decrease in the FIB-4 index, and those that showed deterioration in the fibrosis stage exhibited an increase in the FIB-4 index with a significant correlation (P < 0.001). Increase in the ΔFIB-4 index per year was an independent predictive factor for the progression in liver fibrosis with an odds ratio of 3.90 (P = 0.03). The area under the receiver operating characteristic curve of the ΔFIB-4 index/year for the prediction of advancement to cirrhosis was 0.910. Using a cut-off value of the ΔFIB-4 index/year <0.4 or ≥ 0.4, the cumulative incidence of fibrosis progression to cirrhosis at 5 and 10 years was 34% and 59%, respectively in patients with the ΔFIB-4 index/year ≥0.4, whereas it was 0% and 3% in those with the ΔFIB-4 index/year <0.4 (P < 0.001). In conclusion, measurement of the time-course changes in the FIB-4 index is useful for the noninvasive and real-time estimation of the progression in liver fibrosis.


Assuntos
Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Hepatite C Crônica/complicações , Cirrose Hepática/etiologia , Adulto , Fatores Etários , Idoso , Biópsia , Estudos de Coortes , Demografia , Progressão da Doença , Feminino , Hepatite C Crônica/metabolismo , Hepatite C Crônica/virologia , Humanos , Incidência , Cirrose Hepática/diagnóstico , Cirrose Hepática/metabolismo , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Valor Preditivo dos Testes , Índice de Gravidade de Doença , Fatores de Tempo
7.
J Exp Med ; 188(5): 991-5, 1998 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-9730901

RESUMO

Paired immunoglobulin-like receptor (PIR)-A and PIR-B possess similar ectodomains with six immunoglobulin-like loops, but have distinct transmembrane and cytoplasmic domains. PIR-B bears immunoreceptor tyrosine-based inhibitory motif (ITIM) sequences in its cytoplasmic domain that recruit Src homology (SH)2 domain-containing tyrosine phosphatases SHP-1 and SHP-2, leading to inhibition of B and mast cell activation. In contrast, the PIR-A protein has a charged Arg residue in its transmembrane region and a short cytoplasmic domain that lacks ITIM sequences. Here we show that Fc receptor gamma chain, containing an immunoreceptor tyrosine-based activation motif (ITAM), associates with PIR-A. Cross-linking of this PIR-A complex results in mast cell activation such as calcium mobilization in an ITAM-dependent manner. Thus, our data provide evidence for the existence of two opposite signaling pathways upon PIR aggregation. PIR-A induces the stimulatory signal by using ITAM in the associated gamma chain, whereas PIR-B mediates the inhibitory signal through its ITIMs.


Assuntos
Mastócitos/metabolismo , Receptores de IgG/metabolismo , Receptores Imunológicos/fisiologia , Animais , Linfócitos B/metabolismo , Northern Blotting , Western Blotting , Linhagem Celular , Galinhas , Humanos , Substâncias Macromoleculares , Mastócitos/enzimologia , Mastócitos/imunologia , Camundongos , Testes de Precipitina , Proteínas Tirosina Quinases/metabolismo , Receptores de IgG/genética , Receptores Imunológicos/genética , Proteínas Recombinantes de Fusão/metabolismo
8.
J Exp Med ; 187(8): 1355-60, 1998 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-9547347

RESUMO

Paired immunoglobulin-like receptor B (PIR-B) (p91) molecule has been proposed to function as an inhibitory receptor in B cells and myeloid lineage cells. We demonstrate here that the cytoplasmic region of PIR-B is capable of inhibiting B cell activation. Mutational analysis of five cytoplasmic tyrosines indicate that tyrosine 771 in the motif VxYxxL plays the most crucial role in mediating the inhibitory signal. PIR-B-mediated inhibition was markedly reduced in the SH2-containing protein tyrosine phosphatases SHP-1 and SHP-2 double-deficient DT40 B cells, whereas this inhibition was unaffected in the inositol polyphosphate 5'-phosphatase SHIP-deficient cells. These data demonstrate that PIR-B can negatively regulate B cell receptor activation and that this PIR-B-mediated inhibition requires redundant functions of SHP-1 and SHP-2.


Assuntos
Linfócitos B/imunologia , Ativação Linfocitária , Proteínas Tirosina Fosfatases/metabolismo , Receptores de Antígenos de Linfócitos B/antagonistas & inibidores , Receptores Imunológicos/metabolismo , Antígenos CD/metabolismo , Células da Medula Óssea/imunologia , Cálcio/metabolismo , Análise Mutacional de DNA , Peptídeos e Proteínas de Sinalização Intracelular , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases , Monoéster Fosfórico Hidrolases/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11 , Proteína Tirosina Fosfatase não Receptora Tipo 6 , Receptores de IgG/metabolismo , Transdução de Sinais
9.
J Exp Med ; 192(6): 847-56, 2000 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-10993915

RESUMO

B cell linker protein (BLNK) and Src homology 2 domain-containing leukocyte protein of 76 kD (SLP-76) are adaptor proteins required for B cell receptor (BCR) and T cell receptor function, respectively. Here, we show that expression of SLP-76 cannot reconstitute BCR function in Zap-70(+)BLNK(-) B cells. This could be attributable to inability of SLP-76 to be recruited into glycolipid-enriched microdomains (GEMs) after antigen receptor cross-linking. Supporting this idea, the BCR function was restored when a membrane-associated SLP-76 chimera was enforcedly localized to GEMs. Moreover, we demonstrate that addition of both linker for activation of T cells (LAT) and Grb2-related adaptor downstream of Shc (Gads) to SLP-76 allow SLP-76 to be recruited into GEMs, whereby the BCR function is reconstituted. The Gads function was able to be replaced by overexpression of Grb2. In contrast to SLP-76, BLNK did not require Grb2 families for its recruitment to GEMs. Hence, these data suggest a functional overlap between BLNK and SLP-76, while emphasizing the difference in requirement for additional adaptor molecules in their targeting to GEMs.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Linfócitos B/imunologia , Proteínas de Transporte/metabolismo , Membrana Celular/imunologia , Proteínas de Membrana , Fosfoproteínas/metabolismo , Proteínas/metabolismo , Receptores de Antígenos de Linfócitos B/imunologia , Animais , Proteínas de Transporte/imunologia , Galinhas , Receptores ErbB/fisiologia , Proteína Adaptadora GRB2 , Biblioteca Gênica , Humanos , Fosfoproteínas/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Transdução de Sinais
10.
J Exp Med ; 191(4): 641-50, 2000 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-10684856

RESUMO

Accumulating evidence indicates that the Cbl protein plays a negative role in immune receptor signaling; however, the mode of Cbl action in B cell receptor (BCR) signaling still remains unclear. DT40 B cells deficient in Cbl showed enhanced BCR-mediated phospholipase C (PLC)-gamma2 activation, thereby leading to increased apoptosis. A possible explanation for the involvement of Cbl in PLC-gamma2 activation was provided by findings that Cbl interacts via its Src homology 2 (SH2) domain with B cell linker protein (BLNK) after BCR ligation. BLNK is a critical adaptor molecule for PLC-gamma2 tyrosine phosphorylation through its binding to the PLC-gamma2 SH2 domains. As a consequence of the interaction between Cbl and BLNK, the BCR-induced recruitment of PLC-gamma2 to BLNK and the subsequent PLC-gamma2 tyrosine phosphorylation were inhibited. Thus, our data suggest that Cbl negatively regulates the PLC-gamma2 pathway by inhibiting the association of PLC-gamma2 with BLNK.


Assuntos
Linfócitos B/imunologia , Isoenzimas/metabolismo , Receptores de Antígenos de Linfócitos B/imunologia , Proteínas Oncogênicas de Retroviridae/fisiologia , Fosfolipases Tipo C/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Apoptose , Proteínas de Transporte/metabolismo , Galinhas , Ativação Enzimática , Biblioteca Genômica , Humanos , Isoenzimas/genética , Cariotipagem , Mutagênese Sítio-Dirigida , Proteína Oncogênica v-cbl , Fosfolipase C gama , Fosfoproteínas/metabolismo , Proteínas Recombinantes/metabolismo , Proteínas Oncogênicas de Retroviridae/genética , Transdução de Sinais , Fosfolipases Tipo C/genética
11.
J Exp Med ; 188(7): 1287-95, 1998 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-9763608

RESUMO

Mitogen-activated protein (MAP) kinase family members, including extracellular signal-regulated kinase (ERK), c-Jun NH2-terminal kinase ( JNK), and p38 MAP kinase, have been implicated in coupling the B cell antigen receptor (BCR) to transcriptional responses. However, the mechanisms that lead to the activation of these MAP kinase family members have been poorly elucidated. Here we demonstrate that the BCR-induced ERK activation is reduced by loss of Grb2 or expression of a dominant-negative form of Ras, RasN17, whereas this response is not affected by loss of Shc. The inhibition of the ERK response was also observed in phospholipase C (PLC)-gamma2-deficient DT40 B cells, and expression of RasN17 in the PLC-gamma2-deficient cells completely abrogated the ERK activation. The PLC-gamma2 dependency of ERK activation was most likely due to protein kinase C (PKC) activation rather than calcium mobilization, since loss of inositol 1,4,5-trisphosphate receptors did not affect ERK activation. Similar to cooperation of Ras with PKC activation in ERK response, both PLC-gamma2-dependent signal and GTPase are required for BCR-induced JNK and p38 responses. JNK response is dependent on Rac1 and calcium mobilization, whereas p38 response requires Rac1 and PKC activation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Isoenzimas/metabolismo , Proteínas Quinases Ativadas por Mitógeno , Receptores de Antígenos de Linfócitos B/metabolismo , Transdução de Sinais , Fosfolipases Tipo C/metabolismo , Animais , Linhagem Celular , Galinhas , Ativação Enzimática , Proteína Adaptadora GRB2 , Proteínas de Ligação ao GTP/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno , Proteína Quinase 1 Ativada por Mitógeno , Fosfolipase C gama , Proteína Quinase C/metabolismo , Proteínas/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno , Proteínas rac de Ligação ao GTP
12.
Eur Phys J E Soft Matter ; 30(3): 283-90, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19856005

RESUMO

Recently, two regimes of viscous friction on textured surfaces were proposed in the context of penetration of liquid film into the texture (EPL 79, 56005 (2007)): the Poiseuille and Stokes regimes. With this idea on viscous friction, we theoretically discuss instabilities on a liquid film on textured surfaces when the film is forced to move with external forces. When a film recedes due to a pressure drop, we find scaling laws for instabilities to be checked in future experiments. When a circular film expands due to centrifugal force we find that the expanding film is stable against rim fluctuations (within the linear stability analysis) with its radius determined by a simple equation. Our discussion sheds light on the curvature of the front of the moving liquid film on textured surfaces and how the film thickness is kept fixed to the texture height on textured surfaces, aspects which have not been discussed in previous studies.

13.
J Clin Invest ; 96(1): 224-30, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7542279

RESUMO

We have previously demonstrated that sensitivity to interferon is different among hepatitis C virus (HCV) quasispecies simultaneously detected in same individuals and that interferon-resistant HCV quasispecies are selected during the treatment. To determine the genetic basis of their resistance to interferon, HCV genotype-1b was obtained from serum of three patients before and during interferon therapy, and their full-length nucleotide and deduced amino acid sequences were determined. Comparison of the pairs of interferon-resistant and interferon-sensitive HCV isolates in respective individuals demonstrated clusters of amino acid differences in the COOH-terminal half of the NS5A region (codon 2154-2383), which contained a common unique amino acid difference at codon 2218. Additional sequence data of the COOH-terminal half of the NS5A region obtained from six interferon-resistant and nine interferon-sensitive HCV confirmed the exclusive existence of missense mutations in a 40 amino acid stretch of the NS5A region around codon 2218 (from codon 2209 to 2248) in interferon-sensitive HCV. On the other hand, this region of interferon-resistant HCV was identical to that of prototype HCV genotype-1b (HCV-J, HCV-JTa, or HC-J4). We designated this region as the interferon sensitivity determining region. Thus, HCV genotype-1b with the prototype interferon sensitivity determining region appears to be interferon-resistant strains. The specific nature of these mutations might make it possible to predict prognostic effects of interferon treatment.


Assuntos
Hepacivirus/efeitos dos fármacos , Interferons/farmacologia , Proteínas não Estruturais Virais/química , Adulto , Idoso , Sequência de Aminoácidos , Sequência de Bases , Resistência a Medicamentos , Feminino , Genoma Viral , Hepacivirus/genética , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Relação Estrutura-Atividade
14.
Biochim Biophys Acta ; 1489(2-3): 207-22, 1999 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-10673024

RESUMO

In this article, we report on the chromosome mapping and molecular cloning of the genetic locus encoding the mouse molybdo-iron/sulfur-flavoprotein aldehyde oxidase. The aldehyde oxidase locus maps to mouse chromosome 1 band C1-C2, as determined by fluorescence in situ hybridization experiments conducted on metaphase chromosomes. The gene is approximately 83 kb long and consists of 35 exons. The exon/intron boundaries are perfectly conserved relative to the corresponding human homolog and almost completely conserved relative to the mouse xanthine oxidoreductase gene. This further supports the concept that the aldehyde oxidase and xanthine oxidoreductase loci evolved from the same ancestral precursor by a gene duplication event. The position of a major transcription start site was defined by primer extension and RNase mapping analysis. The 5'-flanking region of the mouse aldehyde oxidase gene contains a functional and orientation-dependent promoter as well as several putative binding sites for known cell-specific and general transcription factors. Deletion analysis of the 5'-flanking region defines an approximately 470 bp DNA stretch which is necessary and sufficient for the transcription of the mouse aldehyde oxidase gene.


Assuntos
Aldeído Oxirredutases/genética , Mapeamento Cromossômico , Aldeído Oxidase , Sequência de Aminoácidos , Animais , Sequência de Bases , Células COS , Clonagem Molecular , DNA , Primers do DNA , Humanos , Hibridização in Situ Fluorescente , Camundongos , Regiões Promotoras Genéticas , Homologia de Sequência de Aminoácidos , Células Tumorais Cultivadas
15.
Cancer Lett ; 71(1-3): 119-23, 1993 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-7689925

RESUMO

The c-met oncogene product is a cell-surface receptor, which ligand is believed to be the hepatocyte growth factor. We studied the expression of c-met oncogene in the regenerating rat liver after either partial hepatectomy or CCl4-induced liver injury. Northern blot analysis showed that after partial hepatectomy the transcripts of c-met decreased at 8 h, reached the minimum at 36 h, and returned to the steady level on the seventh day. In contrast with the hepatectomized liver, the transcripts of c-met increased after CCl4 treatment. These observations suggest that c-met transcription may be regulated differently depending on regeneration signals.


Assuntos
Regeneração Hepática , Proteínas Proto-Oncogênicas/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Tetracloreto de Carbono/administração & dosagem , Hepatectomia , Regeneração Hepática/genética , Masculino , Dados de Sequência Molecular , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-met , RNA/isolamento & purificação , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
16.
Neuroreport ; 8(9-10): 2343-9, 1997 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-9243637

RESUMO

Aldehyde oxidase (AO), a protein involved in the catabolism of catecholamines, is the product of a gene potentially responsible for one of the familial forms of the motor neuron disease, amyotrophic lateral sclerosis (ALS). Here, we report on the cloning of a partial cDNA coding for the mouse enzyme. Using this cDNA as a probe, we demonstrate that the AO transcript is expressed in the epithelial component of the choroid plexus. More importantly, in the gray matter, the mRNA is selectively localized in the large motor neurons of the nuclei of facial, motor trigemini and hypoglossus nerves and in the motor neurons of the anterior horns of the spinal cord. This localization is consistent with a possible role of AO in the pathogenesis of ALS.


Assuntos
Aldeído Oxirredutases/metabolismo , Plexo Corióideo/enzimologia , Neurônios Motores/enzimologia , Aldeído Oxidase , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar , Hibridização In Situ , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , RNA Mensageiro/metabolismo , Medula Espinal/enzimologia
17.
Eur J Pharmacol ; 317(2-3): 369-76, 1996 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-8997623

RESUMO

In previous work, we reported that chlorpromazine inhibits tumor necrosis factor (TNF) production in endotoxin lipopolysaccharide-treated mice, and protects against lipopolysaccharide toxicity. Chlorpromazine is used as an antipsychotic and has several effects on the central nervous system. It acts on different neurotransmitter receptors and has other biochemical activities some of which, like inhibition of phospholipase A2, might be responsible for the inhibitory effect on TNF production. To investigate the role of these actions in the inhibition of TNF production by chlorpromazine, we have synthesized some chlorpromazine derivatives that do not have central activities. Some of these analogs have lost their affinity for various receptors and their phospholipase A2 inhibitory activity, but still inhibit TNF production. No correlation was found between TNF inhibition and the ability to inhibit nitric oxide (NO) synthase, whereas a good correlation was evident between TNF inhibition and antioxidant activity.


Assuntos
Antioxidantes/farmacologia , Clorpromazina/análogos & derivados , Clorpromazina/farmacologia , Fator de Necrose Tumoral alfa/biossíntese , Animais , Pressão Sanguínea/efeitos dos fármacos , Depressão Química , Inibidores Enzimáticos/farmacologia , Técnicas In Vitro , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Atividade Motora/efeitos dos fármacos , Óxido Nítrico Sintase/antagonistas & inibidores , Fosfolipases A/antagonistas & inibidores , Fosfolipases A2 , Ratos , Ratos Wistar , Receptores de Neurotransmissores/efeitos dos fármacos , Receptores de Neurotransmissores/metabolismo , Suínos
18.
Neurosurgery ; 47(4): 843-8; discussion 848-9, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11014423

RESUMO

OBJECTIVE: The goal of this study was to evaluate the efficacy and safety of transsphenoidal pituitary surgery for elderly patients, using improved techniques of the past decade. METHODS: We retrospectively analyzed 32 surgically treated cases of clinically nonsecreting pituitary adenomas in patients more than 70 years of age (mean, 73.9+/-3.4 yr). These patients were identified in a review of 982 patients with pituitary adenomas who were treated at University Hospital Eppendorf, Hamburg, between January 1991 and November 1999. RESULTS: The mean preoperative duration of symptoms was 1.9 years (2 wk to 11 yr). The chiasmatic syndrome was present for 27 patients (84.4%). All patients underwent transsphenoidal surgery. Seven patients underwent reoperations. Preoperative assessments of anterior pituitary function revealed growth hormone deficiencies for 21 of 27 patients (77.8%), thyroid insufficiencies for 10 of 30 patients (33.3%), and adrenal insufficiencies for 13 of 29 patients (44.8%). Hypogonadism and hyperprolactinemia were observed for 76.7% and 46.9% of the patients, respectively. All tumors were macroadenomas, ranging from 18 to 50 mm (average, 33.6 mm) in size, including 7 enclosed and 25 invasive adenomas. Complete microscopic tumor resection was achieved in 24 cases, and subtotal removal was performed in 8 cases. There were no severe perioperative complications. In the cases involving hyperprolactinemia, serum prolactin levels were normalized for 8 of 11 patients (72.7%). Normal thyroid function was recovered for 1 of 10 patients (10.0%) with preoperative hypothyroidism. However, growth hormone or adrenal insufficiencies persisted for all patients with preoperative insufficiencies. Visual disturbances were improved for 19 of 23 patients (82.6%). All patients recovered well after surgery, with an average hospital stay of 16.3 days. Histological and immunohistochemical studies demonstrated gonadotroph adenomas in 56.7% of cases, null-cell adenomas in 26.7%, and oncocytomas in 13.3%. CONCLUSION: Surgical treatment of nonsecreting pituitary adenomas causing visual disturbances is standard, even for elderly patients. In this series, transsphenoidal surgery was a safe procedure, with minimal morbidity and excellent tolerance. Age alone is not a contraindication for active treatment, particularly with transsphenoidal surgery.


Assuntos
Adenoma/cirurgia , Neoplasias Hipofisárias/cirurgia , Adenoma/complicações , Adenoma/patologia , Idoso , Idoso de 80 Anos ou mais , Doenças do Sistema Endócrino/etiologia , Feminino , Cefaleia/etiologia , Humanos , Masculino , Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/patologia , Reoperação , Estudos Retrospectivos , Resultado do Tratamento , Transtornos da Visão/etiologia
19.
Neurosurgery ; 33(1): 50-6; discussion 56-7, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8355847

RESUMO

A SUBTEMPORAL AMYGDALOHIPPOCAMPECTOMY technique has been developed for mesial temporal lobe epilepsy. The conventional subtemporal approach has been modified to diminish temporal lobe retraction and the risk of damage to the temporal lobe. In the new technique, the surgeons' position has moved from above to below and the approach has been changed from anterolateral to posterolateral, thereby avoiding the voluminous and steeply inclined anterior temporal lobe. By this modified approach, it was unnecessary to remove the roof of the external auditory meatus and it was estimated that both the retraction pressure and the extent of temporal lobe retraction were reduced. To date, surgeons using this approach have operated on four patients with temporal lobe epilepsy whose epileptic foci were in the mesial temporal structure; the inferior temporal gyrus, the temporal tip, the vein of Labbé, and the ventral bridging veins were preserved. After surgery, two patients became completely free of seizures and the other two showed over 90% reduction in seizure frequency without neurological sequelae. Postoperative visual field examination revealed full visual fields without quadrantanopsia. This approach can preserve the temporal stem and lateral temporal lobe, it can be used to remove as much of the posterior hippocampus as necessary, and it can be extended to conventional lobectomy if it is indicated.


Assuntos
Tonsila do Cerebelo/cirurgia , Epilepsia Parcial Complexa/cirurgia , Epilepsia do Lobo Temporal/cirurgia , Hipocampo/cirurgia , Adulto , Tonsila do Cerebelo/patologia , Epilepsia Parcial Complexa/patologia , Epilepsia do Lobo Temporal/patologia , Feminino , Hipocampo/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Resultado do Tratamento , Transtornos da Visão/prevenção & controle
20.
J Neurosurg ; 94(1 Suppl): 158-61, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11147855

RESUMO

The Currarino triad is a unique complex of congenital caudal anomalies including anorectal malformation, sacral bone abnormality, and presacral mass. In this report, the authors describe three cases with the complete Currarino triad in a family. The authors treated a 30-year-old mother with an anterior sacral meningocele, her 1-year-old son with a combination of anterior sacral meningocele and dermoid cyst, and her 4-year-old daughter with an epidermoid cyst. These three patients had associated sacral agenesis and anorectal malformations. To the authors' knowledge, this is the first report describing radiological and operative findings of complete familial Currarino triad in which a mother and her two children were affected.


Assuntos
Anormalidades Múltiplas , Canal Anal/anormalidades , Cisto Dermoide/complicações , Cisto Epidérmico/complicações , Meningocele/complicações , Reto/anormalidades , Sacro/anormalidades , Adulto , Pré-Escolar , Cisto Epidérmico/diagnóstico , Cisto Epidérmico/patologia , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Meningocele/diagnóstico por imagem , Meningocele/cirurgia , Mielografia , Sacro/diagnóstico por imagem , Sacro/patologia , Síndrome
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