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1.
Br J Surg ; 107(3): 289-300, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31873948

RESUMO

BACKGROUND: The safety and oncological efficacy of laparoscopic re-resection of incidental gallbladder cancer have not been studied. This study aimed to compare laparoscopic with open re-resection of incidentally discovered gallbladder cancer while minimizing selection bias. METHODS: This was a multicentre retrospective observational cohort study of patients with incidental gallbladder cancer who underwent re-resection with curative intent at four centres between 2000 and 2017. Overall survival (OS) and recurrence-free survival (RFS) were analysed by intention to treat. Inverse probability of surgery treatment weighting using propensity scoring was undertaken. RESULTS: A total of 255 patients underwent re-resection (190 open, 65 laparoscopic). Nineteen laparoscopic procedures were converted to open operation. Surgery before 2011 was the only factor associated with conversion. Duration of hospital stay was shorter after laparoscopic re-resection (median 4 versus 6 days; P < 0·001). Three-year OS rates for laparoscopic and open re-resection were 87 and 62 per cent respectively (P = 0·502). Independent predictors of worse OS were residual cancer found at re-resection (hazard ratio (HR) 1·91, 95 per cent c.i. 1·17 to 3·11), blood loss of at least 500 ml (HR 1·83, 1·23 to 2·74) and at least four positive nodes (HR 3·11, 1·46 to 6·65). In competing-risks analysis, the RFS incidence was higher for laparoscopic re-resection (P = 0·038), but OS did not differ between groups. Independent predictors of worse RFS were one to three positive nodes (HR 2·16, 1·29 to 3·60), at least four positive nodes (HR 4·39, 1·96 to 9·82) and residual cancer (HR 2·42, 1·46 to 4·00). CONCLUSION: Laparoscopic re-resection for selected patients with incidental gallbladder cancer is oncologically non-inferior to an open approach. Dissemination of advanced laparoscopic skills and timely referral of patients with incidental gallbladder cancer to specialized centres may allow more patients to benefit from this operation.


ANTECEDENTES: No se conoce la seguridad y la eficacia oncológica de la re-resección laparoscópica del cáncer incidental de vesícula biliar. Este estudio tiene como objetivo comparar las re-resecciones del cáncer incidental de vesícula biliar por vía laparoscópica y vía abierta, minimizando el sesgo de selección. MÉTODOS: Estudio de cohortes observacional, retrospectivo y multicéntrico de pacientes con cáncer incidental de vesícula biliar que se sometieron a una re-resección con intención curativa en 4 centros entre 2000 y 2017. Se analizó la supervivencia global (overall survival, OS) y la supervivencia libre de recidiva (recurrence free survival, RFS) según intención de tratamiento. Se calculó la probabilidad inversa de la ponderación del tratamiento quirúrgico utilizando puntuación de propensión. RESULTADOS: Se incluyeron 255 pacientes con re-resección (190 por vía abierta y 65 por vía laparoscópica). Se convirtieron 19 pacientes del grupo laparoscópico. El único factor relacionado con la conversión fue la realización de la cirugía antes de año 2011. La mediana de la estancia hospitalaria fue más corta tras la re-resección laparoscópica (4 versus 6 días; P < 0,001). La OS a tres años fue del 87% y del 62% (P = 0,502) para las re-resecciones laparoscópicas y abiertas, respectivamente). Los factores predictivos independientes relacionados con una peor OS fueron el hallazgo de cáncer residual en el momento de la re-resección (cociente de riesgos instantáneos, hazard ratio, HR 1,91; i.c. del 95% 1,17-3,11), una pérdida hemática > 500 ml (HR 1,83; i.c. del 95% 1,23-2,74) y la presencia de ≥ 4 ganglios positivos (HR 3,11; i.c. del 95% 1,46-6,65). En el análisis de riesgo competitivo, la RFS fue mayor para la resección laparoscópica (P = 0,038), pero no hubo diferencias en la OS entre ambos grupos. Los factores predictivos independientes de peor RFS fueron la detección de 1-3 ganglios positivos (HR 2,16; i.c. del 95% 1,29-3,60), ≥ 4 ganglio positivos (HR 4,39; i.c. del 95% 1,96-9,82) y el cáncer residual (HR 2,42; i.c. de 95% 1,46-4,0). CONCLUSIÓN: En pacientes seleccionados, los resultados oncológicos de la re-resección laparoscópica de un cáncer incidental de vesícula biliar no son inferiores a los que se obtienen por vía abierta. Una mayor difusión de las técnicas laparoscópicas avanzadas y una oportuna derivación de los pacientes con cáncer de vesícula biliar incidental a centros especializados podrían permitir que un mayor número de pacientes se beneficiaran de este abordaje.


Assuntos
Colecistectomia Laparoscópica/métodos , Neoplasias da Vesícula Biliar/cirurgia , Laparotomia/métodos , Estadiamento de Neoplasias/métodos , Pontuação de Propensão , Adulto , Idoso , Idoso de 80 Anos ou mais , Chile/epidemiologia , Feminino , Seguimentos , Neoplasias da Vesícula Biliar/diagnóstico , Neoplasias da Vesícula Biliar/mortalidade , Humanos , Achados Incidentais , Masculino , Pessoa de Meia-Idade , Reoperação , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Adulto Jovem
2.
Diabet Med ; 37(12): 2131-2135, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-31872455

RESUMO

AIM: To clarify the prevalence and degree of maternal microchimerism in Japanese children with type 1 diabetes, as well as its effect on phenotypic variation. METHODS: We studied 153 Japanese children with type 1 diabetes, including 124 children positive for ß-cell autoantibodies, and their 71 unaffected siblings. The number of circulating microchimeric cells per 105 host cells was estimated by the use of quantitative-polymerase chain reaction targeting non-transmitted maternal human leukocyte antigen alleles. The results were compared to previous data from white European people. Phenotypic comparison was performed between maternal microchimerism carriers and non-carriers with diabetes. RESULTS: Maternal microchimerism was detected in 15% of children with autoantibody-positive type 1 diabetes, 28% of children with autoantibody-negative type 1 diabetes, and 16% of unaffected siblings. There were no differences in the prevalence or levels of maternal microchimerism among the three groups or between the children with type 1 diabetes and their unaffected siblings. Furthermore, maternal microchimerism carriers and non-carriers exhibited similar phenotypes. CONCLUSIONS: Maternal microchimerism appears to be less common in Japanese children with type 1 diabetes than in white European people. Our data indicate that maternal microchimerism is unlikely to be a major trigger or a phenotypic determinant of type 1 diabetes in Japanese children and that the biological significance of maternal microchimerism in type 1 diabetes may differ among ethnic groups.


Assuntos
Povo Asiático , Autoanticorpos/imunologia , Quimerismo , Diabetes Mellitus Tipo 1/sangue , Troca Materno-Fetal/imunologia , Adolescente , Estudos de Casos e Controles , Criança , Diabetes Mellitus Tipo 1/imunologia , Feminino , Antígenos HLA , Humanos , Japão , Masculino , Mães , Gravidez , Irmãos , Transportador 8 de Zinco/imunologia
3.
Br J Surg ; 105(9): 1200-1209, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29664996

RESUMO

BACKGROUND: Although perihepatic lymph node metastases (PLNMs) are known to be a poor prognosticator for patients with colorectal liver metastases (CRLMs), optimal management remains unclear. This study aimed to determine the risk factors for PLNMs, and the survival impact of their number and location in patients with resectable CRLMs. METHODS: Data on patients with CRLM who underwent hepatectomy during 2003-2014 were analysed retrospectively. Recurrence-free (RFS) and overall (OS) survival were calculated according to presence, number and location of PLNMs. Risk factors for PLNM were evaluated by logistic regression analysis. RESULTS: Of 1485 patients, 174 underwent lymphadenectomy, and 54 (31·0 per cent) had PLNM. Ten patients (5·7 per cent) who had lymphadenectomy and 176 (13·4 per cent) who did not underwent repeat hepatectomy. Survival of patients with PLNM was significantly poorer than that of patients without (RFS: 5·3 versus 13·8 months, P < 0·001; OS: 20·5 versus 71·3 months; P < 0·001). Median OS was significantly better in patients with para-aortic versus hepatoduodenal ligament PLNMs (58·2 versus 15·5 months; P = 0·011). Patients with three or more PLNMs had significantly worse median OS than those with one or two (16·3 versus 25·4 months; P = 0·039). The presence of primary tumour lymph node metastases (odds ratio 2·35; P = 0·037) and intrahepatic recurrence requiring repeat hepatectomy (odds ratio 5·61; P = 0·012) were significant risk factors for PLNM on multivariable analysis. CONCLUSION: Patients undergoing repeat hepatectomy and those with primary tumour lymph node metastases are at significant risk of PLNM. Although PLNM is a poor prognostic factor independent of perihepatic lymph node station, patients with one or two PLNMs have a more favourable outcome than those with more PLNMs.


Assuntos
Neoplasias Colorretais/cirurgia , Hepatectomia , Neoplasias Hepáticas/cirurgia , Estadiamento de Neoplasias , Idoso , Biópsia , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/secundário , Metástase Linfática , Masculino , Prognóstico , Estudos Prospectivos , Taxa de Sobrevida/tendências , Texas/epidemiologia , Tomografia Computadorizada por Raios X
4.
Diabet Med ; 35(3): 376-380, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29247561

RESUMO

AIM: To examine the contribution of PTPN2 coding variants to the risk of childhood-onset Type 1A diabetes. METHODS: PTPN2 mutation analysis was carried out for 169 unrelated Japanese people with childhood-onset Type 1A diabetes. We searched for coding variants that were absent or extremely rare in the general population and were scored as damaging by multiple in silico programs. We performed mRNA analysis and three-dimensional structural prediction of the detected variants, when possible. We also examined possible physical links between these variants and previously reported risk SNPs as well as clinical information from variant-positive children. RESULTS: One frameshift variant (p.Q286Yfs*24) and two probably damaging missense substitutions (p.C232W and p.R350Q) were identified in one child each. Of these, p.Q286Yfs*24 and p.C232W were hitherto unreported, while p.R350Q accounted for 2/121,122 alleles of the exome datasets. The p.Q286Yfs*24 variant did not encode stable mRNA, and p.C232W appeared to affect the structure of the tyrosine-protein phosphatase domain. The three variants were physically unrelated to known risk SNPs. The variant-positive children manifested Type 1A diabetes without additional clinical features and invariably carried risk human leukocyte antigen alleles. CONCLUSIONS: The results provide the first indication that PTPN2 variants contribute to the risk of Type 1A diabetes, independently of known risk SNPs. PTPN2 coding variants possibly induce non-specific Type 1A diabetes phenotypes in individuals with human leukocyte antigen-mediated disease susceptibility. Our findings warrant further validation.


Assuntos
Diabetes Mellitus Tipo 1/genética , Mutação da Fase de Leitura/genética , Mutação de Sentido Incorreto/genética , Proteína Tirosina Fosfatase não Receptora Tipo 2/genética , Adolescente , Criança , Pré-Escolar , Feminino , Predisposição Genética para Doença/genética , Antígenos HLA/genética , Humanos , Lactente , Masculino , Fases de Leitura Aberta/genética , Polimorfismo de Nucleotídeo Único/genética , RNA Mensageiro/genética
5.
Dis Esophagus ; 24(2): 92-8, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20659140

RESUMO

Transnasal ultrathin esophagogastroduodenoscopy (N-EGD) with less gagging reflexes under non-sedation is likely suitable for the diagnosis of gastroesophageal reflux disease (GERD), however, N-EGD might have drawbacks, including its low image resolution. Limited information is available regarding the diagnosability of N-EGD for GERD. We compared the utility and gagging reflexes of three different endoscopies, including N-EGD, ultrathin transoral EGD (UTO-EGD) and conventional oral EGD (CO-EGD), in the diagnosis of GERD. We performed screening endoscopy in 1580 patients (N-EGD n=727, UTO-EGD n=599, CO-EGD n=254) and compared the frequency distributions of the severity of reflux esophagitis, hiatus hernia, and Barrett's epithelium to estimate the diagnostic performance of each endoscopy. We also analyzed patients' tolerability of endoscopy by the subjective evaluation of gagging reflexes. In the diagnosis of reflux esophagitis and Barrett's epithelium, there was no significant difference in the frequency distributions of the severity of the diseases among three EGDs. However, the incidence of Barrett's epithelium was higher than that in the previous nationwide survey of GERD in Japan. The evaluated size of hiatus hernia was smaller in N-EGD than in two other peroral endoscopies. The size of hiatus hernia correlated significantly with severity of gagging reflexes that was also lowest when diagnosed with N-EGD. N-EGD had an equivalent performance in the diagnosis of reflux esophagitis and Barrett's epithelium compared with CO-EGD. Enlargement of hiatus hernia induced by gagging reflexes was minimal in N-EGD, resulting in its better performance in the diagnosis of Barrett's epithelium.


Assuntos
Esôfago de Barrett/diagnóstico , Endoscopia do Sistema Digestório/métodos , Esofagite Péptica/diagnóstico , Refluxo Gastroesofágico/diagnóstico , Hérnia Hiatal/diagnóstico , Endoscopia do Sistema Digestório/instrumentação , Feminino , Engasgo , Humanos , Masculino , Estudos Prospectivos
6.
J Cell Biol ; 85(3): 712-25, 1980 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6446567

RESUMO

Direct measurements of the stiffness (elastic bending resistance) of demembranated sera urchin sperm flagella were made in the presence of MgATP2- and vanadate. Under these conditions, the flagellum is in a relaxed state, with a stiffness of approximately 0.9 x 10(-21) N m2, which is approximately 5% of the stiffness obtained in the rigor state in the absence of MgATP2-. MgADP- dose not substitute for MgATP2- in producing relaxed state. A progressive inhibition of movement is observed after addition of MgATP2- to flagella preincubated with vanadate, in which new bend generation, propagation, and relaxation by straightening are distinguished, depending on the ratio of MgATP2- and vanadate. At appropriate concentrations of vanadate, increase of the velocity of bend propagation is observed at a very low concentration of MgATP2- that is not enough to induce spontaneous beating. Vanadate enhances competitive inhibition of beat frequency by MgADP- but not by ADP3-, ATP4-, or Pi. These observations, and the uncompetitive inhibition of beat frequency by vanadate, indicate that vanadate can only bind to dynein-nucleotide complexes induced by MgATP2- and MgADP-. The state accessible by MgATP2- binding must be a state in which the cross-bridges are detached and the flagellum is relaxed. The state accessible by MgADP- binding must be a cross-bridged state. Bound vanadate prevents the transition between these two states. Inhibition and relaxation by banadate in the presence of MgATP2- results from the specific affinity of vanadate for a state in which nucleotide is bound, rather than a specific affinity for the deteched state.


Assuntos
Flagelos/efeitos dos fármacos , Motilidade dos Espermatozoides/efeitos dos fármacos , Vanádio/farmacologia , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Dineínas/metabolismo , Masculino , Movimento/efeitos dos fármacos , Ouriços-do-Mar/ultraestrutura , Cauda do Espermatozoide/efeitos dos fármacos
7.
J Cell Biol ; 74(1): 251-63, 1977 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-141455

RESUMO

Antiserum against starfish egg myosin was produced in rabbits. Antibody specificity to myosin was demonstrated by Ouchterlony's immunodiffusion test and by immunoelectrophoresis in the presence of sodium dodecylsulfate (SDS). The latter technique showed that the antibody binds to both heavy and light chains of egg myosin. Furthermore, the antibody reacted with starfish sperm mysosin and starfish adult muscle myosin at both the heavy and light chains. It did not react with bovine platelet mysosin or rabbit skeletal muscle myosin in Ouchterlony's test; however, a weak reaction was observed in the presence of SDS between the antibody and these myosin heavy chains. Ca- and Mg-ATPase activities of egg myosin were not affected by the antibody, but it did inhibit actin-activated ATPase activity of egg myosin. Microinjection of the antibody into blastomeres of starfish eggs at the two-cell stage was carried out. Anti-egg myosin gamma-globulin inhibited the subsequent cleavages at an amount of more than 0.3 ng when injected at interphase. The inhibition was reduced when the injection was carried out near the initiation of cleavage. At the onset of the second cleavage the antibody was not inhibitory; however, an appropriate amount inhibited the third cleavage. Although the disappearance of the nuclear membrane was observed in the presence of the antibody, the formation of the mitotic apparatus was more or less disturbed. However the formation of daughter nuclei seemed to be scarcely affected by the antibody except that the distance between the nuclei was significantly smaller than normal.


Assuntos
Divisão Celular , Miosinas/fisiologia , Zigoto/citologia , Actinas/fisiologia , Adenosina Trifosfatases/metabolismo , Animais , Anticorpos , Feminino , Imunodifusão , Imunoeletroforese , Masculino , Microinjeções , Mitose , Miosinas/imunologia , Espermatozoides , Estrelas-do-Mar
8.
J Cell Biol ; 91(3 Pt 1): 689-94, 1981 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6460037

RESUMO

Antidynein antibodies, previously shown to inhibit flagellar oscillation and active sliding of axonemal microtubules, increase the bending resistance of axonemes measured under relaxing conditions, but not the bending resistance of axonemes measured under rigor conditions. These observations suggest that antidynein antibodies can stabilize rigor cross-bridges between outer-doublet microtubules, by interfering with ATP-induced cross-bridge detachment. Stabilization of a small number of cross-bridge appears to be sufficient to cause substantial inhibition of the frequency of flagellar oscillation. Antitubulin antibodies, previously shown to inhibit flagellar oscillation without inhibiting active sliding of axonemal microtubules, do not increase the static bending resistance of axonemes. However, we observed a viscoelastic effect, corresponding to a large increase in the immediate bending resistance. This immediate bending resistance increase may be sufficient to explain inhibition of flagellar oscillation; but several alternative explanations cannot yet be excluded.


Assuntos
Adenosina Trifosfatases/fisiologia , Dineínas/fisiologia , Flagelos/fisiologia , Tubulina (Proteína)/fisiologia , Animais , Complexo Antígeno-Anticorpo , Fenômenos Biofísicos , Biofísica , Dineínas/imunologia , Masculino , Ouriços-do-Mar , Cauda do Espermatozoide/fisiologia , Tubulina (Proteína)/imunologia
9.
J Cell Biol ; 112(6): 1189-97, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1825661

RESUMO

The substrate specificities of dynein, kinesin, and myosin substrate turnover activity and cytoskeletal filament-driven translocation were examined using 15 ATP analogues. The dyneins were more selective in their substrate utilization than bovine brain kinesin or muscle heavy meromyosin, and even different types of dyneins, such as 14S and 22S dynein from Tetrahymena cilia and the beta-heavy chain-containing particle from the outer-arm dynein of sea urchin flagella, could be distinguished by their substrate specificities. Although bovine brain kinesin and muscle heavy meromyosin both exhibited broad substrate specificities, kinesin-induced microtubule translocation varied over a 50-fold range in speed among the various substrates, whereas heavy meromyosin-induced actin translocation varied only by fourfold. With both kinesin and heavy meromyosin, the relative velocities of filament translocation did not correlate well with the relative filament-activated substrate turnover rates. Furthermore, some ATP analogues that did not support the filament translocation exhibited filament-activated substrate turnover rates. Filament-activated substrate turnover and power production, therefore, appear to become uncoupled with certain substrates. In conclusion, the substrate specificities and coupling to motility are distinct for different types of molecular motor proteins. Such nucleotide "fingerprints" of enzymatic activities of motor proteins may prove useful as a tool for identifying what type of motor is involved in powering a motility-related event that can be reconstituted in vitro.


Assuntos
Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/farmacologia , Cílios/fisiologia , Dineínas/metabolismo , Subfragmentos de Miosina/metabolismo , Tetrahymena/fisiologia , Actinas/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Bovinos , Movimento Celular/efeitos dos fármacos , Cílios/efeitos dos fármacos , Cinesinas , Microtúbulos/efeitos dos fármacos , Microtúbulos/fisiologia , Especificidade por Substrato
10.
Eur J Surg Oncol ; 43(6): 1003-1012, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27624917

RESUMO

PURPOSE: This study aimed to evaluate whether the response rate of chemotherapy with molecular target agents correlates with the conversion rate, R0 resection rate, and survival in patients with initially unresectable colorectal liver metastases (CRLM). METHODS: We reviewed the literature of prospective, controlled trials of systemic chemotherapy for patients with unresectable liver-only CRLM, including resectable extrahepatic metastases. Pearson's correlation coefficients were calculated. RESULTS: A total of 26 patient groups from 18 studies were reviewed. The response rate was significantly correlated with the conversion rate (r = 0.66) and R0 resection rate (r = 0.43) in overall patients. In subgroup analysis, only the conversion rate in patients with chemotherapy only (r = 0.75) and anti-EGFR therapy (r = 0.78) were significantly strongly correlated with the response rate. A non-significant strong trend toward correlation between response and conversion rates was observed in patients with bevacizumab (r = 0.73, p = 0.10). The regression line in the scatter plot of patients using bevacizumab showed a less steep slope. This indicated that conversion rates were relatively less affected by response rates under anti-VEGF therapy compared with the other patient groups. The response rate in chemotherapy-only patients was significantly correlated with median progression-free survival (r = 0.61) and overall survival (r = 0.66). CONCLUSIONS: Chemotherapy without molecular target agents and with anti-EGFR agents shows similar results of correlation between response and conversion/R0 resection rates. Under anti-VEGF therapy, conversion would be expected, even with a relatively lower response rate.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Carcinoma/tratamento farmacológico , Neoplasias Colorretais/patologia , Neoplasias Hepáticas/tratamento farmacológico , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Bevacizumab/uso terapêutico , Carcinoma/secundário , Cetuximab/uso terapêutico , Intervalo Livre de Doença , Receptores ErbB/antagonistas & inibidores , Hepatectomia , Humanos , Neoplasias Hepáticas/secundário , Metastasectomia , Terapia de Alvo Molecular , Panitumumabe , Taxa de Sobrevida , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
11.
Cancer Res ; 61(20): 7675-82, 2001 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-11606411

RESUMO

Retinoids induce apoptosis and differentiation of hepatocellular carcinoma (HCC) cells and are used clinically in the chemoprevention of HCC. We have shown previously that hepatocarcinogenesis is accompanied by accumulation of full-length retinoid X receptor alpha (RXRalpha), although the underlying mechanisms and biological implications have remained unclear. The present studies were based on the finding that the accumulated full-length RXRalpha was phosphorylated at serine/threonine residues both in all human HCC tissues examined and in human HCC-derived HuH7 cells. Phosphorylation at serine 260 of RXRalpha, a consensus site of mitogen-activated protein kinase, was closely linked to its retarded degradation, low transactivating activity, and the promotion of cancer cell growth. There was no genomic mutation in the RXRalpha gene, and abrogation of phosphorylation by mitogen-activated protein kinase-specific inhibitors restored the degradation of RXRalpha in an RXR ligand-dependent manner. These results suggest that phosphorylation of RXRalpha may interfere with its metabolism and signaling in human HCC, which could lead to growth promotion of these tumors.


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Receptores do Ácido Retinoico/metabolismo , Fatores de Transcrição/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Divisão Celular/fisiologia , Humanos , Ligantes , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mutagênese Sítio-Dirigida , Fosforilação , Receptores do Ácido Retinoico/antagonistas & inibidores , Receptores do Ácido Retinoico/genética , Receptores X de Retinoides , Serina/metabolismo , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Ativação Transcricional/fisiologia , Transfecção
12.
Biochim Biophys Acta ; 923(1): 116-24, 1987 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-2432942

RESUMO

Cellular retinoic acid-binding protein (CRABP) has been purified to homogeneity from human placenta by a series of procedures, including acetone powder extraction, gel filtration on Sephadex G-50, and ion-exchange chromatography on DEAE-cellulose and on SP-Sephadex. Cellular retinol-binding protein (CRBP) was isolated concurrently. CRABP was purified 75,400-fold, based on total soluble acetone powder extract of placenta. The protein is a single polypeptide chain with a molecular mass of 14,600 Da, estimated by sodium dodecyl sulfate (SDS) gel electrophoresis or gel filtration, and has an isoelectric point of 4.78 (apo-CRABP, 4.82). On analysis of absorption and fluorescence spectra, the protein was seen to exhibit an absorption peak at 350 nm, fluorescence excitation maxima at 350 and 370 nm, and a fluorescence emission maximum at 475 nm. Human CRABP was immunologically distinct from human CRBP and serum retinol-binding protein.


Assuntos
Proteínas de Transporte/isolamento & purificação , Placenta/análise , Proteínas de Transporte/imunologia , Cromatografia em Gel , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Epitopos/imunologia , Feminino , Humanos , Ponto Isoelétrico , Peso Molecular , Gravidez , Receptores do Ácido Retinoico , Espectrometria de Fluorescência , Espectrofotometria
13.
Biochim Biophys Acta ; 1389(1): 67-75, 1998 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-9443605

RESUMO

We previously found that lysophosphatidic acid (LPA), a bioactive phospholipid, induced Na+-dependent Ca2+ efflux from cultured bovine adrenal chromaffin cells, possibly by activating a Na+/Ca2+ exchanger. The present study on the structure-activity relationship of its action revealed that 1-acyl type LPAs were stronger stimulants than the corresponding 1-O-alkyl type LPAs having a long alkyl moiety with the same chain length. Lysophosphatidylglycerol, suramin and N-palmitoyl-tyrosine phosphoric acid have all been reported to inhibit the action of LPA in some animal cells and platelets, but only lysophosphatidylglycerol was found to inhibit selectively LPA-induced Ca2+ efflux from chromaffin cells. LPA-induced Ca2+ extrusion was suggested to be involved in both acceleration of return of intracellular Ca2+ in Fura 2-loaded bovine chromaffin cells after addition of carbachol, and inhibition of carbachol-induced catecholamine release when the cells were co-incubated with LPA. The Ca2+ efflux from chromaffin cells stimulated by LPA was augmented by their pretreatment with staurosporine or calphostin C, inhibitors of protein kinase C, but reduced by their preincubation with phorbol 12-myristate 13-acetate. Furthermore, the response to LPA was potentiated by sodium vanadate, a protein tyrosine phosphatase inhibitor, but inhibited by genistein, an inhibitor of protein tyrosine kinase. These results suggest that protein kinase C and protein tyrosine kinase are involved negatively and positively, respectively, in the signal transduction triggered by LPA, leading to activation of the Na+/Ca2+ exchanger.


Assuntos
Glândulas Suprarrenais/metabolismo , Cálcio/metabolismo , Lisofosfolipídeos/farmacologia , Proteínas Quinases/metabolismo , Trocador de Sódio e Cálcio/metabolismo , Glândulas Suprarrenais/efeitos dos fármacos , Animais , Carbacol/farmacologia , Catecolaminas/metabolismo , Bovinos , Células Cromafins/efeitos dos fármacos , Células Cromafins/metabolismo , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Inibidores Enzimáticos/farmacologia , Genisteína/farmacologia , Lisofosfolipídeos/química , Naftalenos/farmacologia , Inibidores de Proteínas Quinases , Transdução de Sinais , Sódio/metabolismo , Estaurosporina/farmacologia , Relação Estrutura-Atividade , Suramina/farmacologia , Acetato de Tetradecanoilforbol/farmacologia , Vanadatos/farmacologia
14.
Biochim Biophys Acta ; 1037(2): 192-9, 1990 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-2155026

RESUMO

A novel cellular retinol-binding protein, termed type three (CRBP III), was isolated from eyes of the bigeye of tuna. CRBP III showed a molecular weight of 15,400, an isoelectric point of 4.80, alpha 1-mobility in electrophoresis, and a lambda max of 350 nm. All-trans-retinol, the endogenous ligand, could be competitively displaced by retinoic acid but not by retinal. CRBP III was differentiated from purified piscine and rat cellular retinol-binding proteins (CRBP) and cellular retinoic acid-binding proteins (CRABP) by its amino-acid composition, electrophoretic mobility, fluorescence spectra and ligand-binding specificity.


Assuntos
Proteínas de Transporte/isolamento & purificação , Olho/análise , Retina/análise , Proteínas de Ligação ao Retinol/isolamento & purificação , Aminoácidos/análise , Animais , Cromatografia DEAE-Celulose , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Peso Molecular , Receptores do Ácido Retinoico , Proteínas Celulares de Ligação ao Retinol , Espectrometria de Fluorescência , Atum
15.
Clin Cancer Res ; 3(5): 727-31, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9815742

RESUMO

A goal of cancer chemoprevention is the deletion of latent premalignant or malignant clones before they expand to a clinically detectable tumor. However, such clonal deletion has not been demonstrated in clinical studies. We have evaluated serum levels of lectin-reactive alpha-fetoprotein (AFP-L3), which suggests the presence of latent hepatoma cells, in a randomized controlled trial that used acyclic retinoid to prevent second primary hepatomas in patients who had received treatments that cured initial hepatomas. The trial involved 21 patients in each acyclic retinoid (600 mg daily) and placebo group and consisted of a 12-month period of drug administration and a subsequent follow-up period. Serum AFP-L3 was determined at entry and at the end of the 12-month treatment period using lectin-affinity electrophoresis and antibody-affinity blotting. Although neither treatment affected serum levels of total AFP, acyclic retinoid significantly reduced AFP-L3 levels after a 12-month administration (P < 0.01). Acyclic retinoid not only deleted AFP-L3 from patients who had been positive for AFP-L3 at entry but also prevented the appearance of AFP-L3 in patients who had been negative at entry (P < 0.01). In contrast, placebo significantly raised the incidence of AFP-L3-positive patients after a 12-month administration from that at entry (P < 0.05). Patients positive for AFP-L3 after a 12-month treatment had a significantly higher risk of second primary hepatomas in the subsequent follow-up period (P = 0.03). Acyclic retinoid may have deleted a clone of latent hepatoma cells producing AFP-L3 and thereby inhibited second primary hepatomas. Serum AFP-L3 may be a useful intermediate biomarker in the chemoprevention of second primary hepatomas by acyclic retinoid.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/prevenção & controle , Neoplasias Hepáticas/prevenção & controle , Segunda Neoplasia Primária/prevenção & controle , Tretinoína/análogos & derivados , alfa-Fetoproteínas/análise , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/cirurgia , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Lectinas , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Segunda Neoplasia Primária/sangue , Placebos , Fatores de Tempo , Tretinoína/uso terapêutico
16.
Biol Psychiatry ; 44(12): 1329-36, 1998 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-9861476

RESUMO

BACKGROUND: Several lines of evidence indicate that abnormalities in brain dopamine and serotonin metabolism may play an important role in bulimia nervosa. However, the regional neurochemical mechanism of the binge eating is poorly understood. Our purpose was to elucidate brain neurochemical mechanisms of binge eating using a rat model. METHODS: The dopamine release and metabolism in the prefrontal cortex (PFC) and in the ventrolateral striatum (VLS) of rats were studied using microdialysis during enhanced rebound hyperphagia induced by space restriction (an animal model of binge eating). RESULTS: The rats showed rebound hyperphagic state when they were released from scheduled feeding (2 hours/day feeding for 7 days). The hyperphagia was further enhanced when they were put in a space-restricted cage where their mobility was restricted. Dopamine release and metabolism were increased both in the PFC and in the VLS during the enhanced rebound hyperphagia. CONCLUSIONS: These results tentatively suggest that increased dopamine release and metabolism in the PFC and in the VLS may be related to space restriction and to activation of motor function involved in feeding behavior, respectively. The enhanced rebound hyperphagia induced by space restriction may be useful as an animal model of binge eating.


Assuntos
Dopamina/metabolismo , Hiperfagia/metabolismo , Neostriado/metabolismo , Córtex Pré-Frontal/metabolismo , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Bulimia/metabolismo , Cromatografia Líquida de Alta Pressão , Modelos Animais de Doenças , Ingestão de Alimentos , Feminino , Ácido Homovanílico/metabolismo , Microdiálise , Ratos , Ratos Wistar
17.
FEBS Lett ; 411(1): 102-6, 1997 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-9247151

RESUMO

We studied the mechanism by which 9,13-di-cis-retinoic acid (9,13dcRA), a novel and endogenous stereoisomer of all-trans-RA, induces TGF-beta formation in a human liver stellate cell line, LI90. 9,13dcRA induced the expression of RAR alpha and RARbeta, enhanced the production of tissue-type plasminogen activator (tPA), thereby, surface plasmin levels, and induced the activation of latent TGF-beta. Similar effects were obtained with RAR alpha-selective retinoid, but not with RARbeta- or RARgamma-selective retinoid, and the induction was inhibited by RAR alpha-selective antagonist. These results suggest that 9,13dcRA up-regulates tPA expression, resulting in the formation of TGF-beta by LI90 cells, at least in part, via induction and activation of RAR alpha.


Assuntos
Fígado/metabolismo , Receptores do Ácido Retinoico/metabolismo , Ativador de Plasminogênio Tecidual/biossíntese , Fator de Crescimento Transformador beta/metabolismo , Tretinoína/análogos & derivados , Animais , Linhagem Celular , Células Cultivadas , Humanos , Fígado/citologia , Fígado/efeitos dos fármacos , RNA Mensageiro , Ratos , Receptores do Ácido Retinoico/agonistas , Receptores do Ácido Retinoico/antagonistas & inibidores , Receptores do Ácido Retinoico/biossíntese , Receptores do Ácido Retinoico/genética , Receptor alfa de Ácido Retinoico , Fator de Crescimento Transformador beta/genética , Tretinoína/farmacologia
18.
FEBS Lett ; 228(2): 301-4, 1988 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-3342884

RESUMO

The cDNA that encodes goat growth hormone (gGH) was isolated from a goat pituitary cDNA library. The cDNA, about 880 base pairs long, had a coding sequence, 5'- and 3'-untranslated regions and a poly(A) chain. The cDNA could encode a polypeptide of 217 amino acids. The amino acid sequence homology between gGH and the sequences of bovine GH, rat GH and human GH was 99, 83 and 66%, respectively. By Northern blot hybridization, we found that the possible gGH gene is transcribed in the goat pituitary.


Assuntos
Clonagem Molecular , DNA/genética , Cabras/genética , Hormônio do Crescimento/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Recombinante , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Hipófise/análise , RNA Mensageiro/genética , Homologia de Sequência do Ácido Nucleico
19.
Atherosclerosis ; 84(2-3): 213-7, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2149270

RESUMO

The effect of low dose (600 mg/day) alpha-tocopheryl nicotinate on serum lipoprotein(a) (Lp(a] concentration was studied in 28 hyperlipidaemic patients. Serum lipids, lipoproteins and apolipoproteins, except for Lp(a), tended to increase after treatment. In particular, the changes in HDL-cholesterol and apo C-II levels were statistically significant. On the other hand, serum Lp(a) levels in all patients decreased significantly after 2 months of treatment. Furthermore, no difference between before and after treatment was observed in the group with initial Lp(a) levels less than 18 mg/dl, whereas Lp(a) concentrations decreased significantly after treatment in the group with levels greater than or equal to 18 mg/dl. The effects of probucol and alpha-tocopheryl nicotinate on serum Lp(a), total cholesterol and HDL-cholesterol were entirely different. Possible mechanisms of alpha-tocopheryl nicotinate on serum Lp(a) and lipoprotein metabolism are discussed.


Assuntos
Hiperlipidemias/tratamento farmacológico , Lipoproteínas/sangue , Ácidos Nicotínicos/uso terapêutico , Vitamina E/análogos & derivados , Adulto , Idoso , Apolipoproteína C-II , Apolipoproteínas C/sangue , Colesterol/sangue , HDL-Colesterol/sangue , Feminino , Humanos , Hiperlipidemias/sangue , Lipoproteína(a) , Masculino , Pessoa de Meia-Idade , Probucol/uso terapêutico , Vitamina E/uso terapêutico
20.
Am J Med Genet ; 99(4): 286-8, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11251994

RESUMO

We describe a Japanese girl with Bernard-Soulier syndrome and 22q11.2 microdeletion. She had viral infections and recurrent thrombocytopenia and hemorrhagic diathesis after cardiac surgery. As congenital heart defects and abnormal immunity are the most common clinical manifestations associated with 22q11.2 deletion, patients with this association may have a greater risk of developing a severe bleeding disorder.


Assuntos
Síndrome de Bernard-Soulier/genética , Deleção Cromossômica , Cromossomos Humanos Par 22/genética , Anormalidades Múltiplas/genética , Adulto , Síndrome de Bernard-Soulier/sangue , Síndrome de Bernard-Soulier/complicações , Saúde da Família , Feminino , Humanos , Imunofenotipagem , Hibridização in Situ Fluorescente , Recém-Nascido , Infecções/etiologia , Masculino , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo , Hemorragia Pós-Operatória/etiologia , Trombocitopenia/etiologia
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