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1.
Orthop Traumatol Surg Res ; 102(8): 1023-1028, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27865687

RESUMO

BACKGROUND: Risk factors for hemorrhage in patients with pelvic ring fracture have been widely reported. Because there are many risk factors, it is thought that prediction accuracy of hemorrhage in cases of pelvic ring fracture could be improved by using a scoring system. HYPOTHESIS: We investigated the risk factors for massive hemorrhage (MH) and created a novel predictive score of MH in pelvic ring fractures. MATERIAL AND METHODS: We retrospectively reviewed patients with pelvic ring fractures (Abbreviated Injury Score≥3 and age≥16 years) from January 2007 to June 2015. We excluded the cases that might have hemorrhage from other sites sufficient to require a blood transfusion. Massive hemorrhage was defined as hemorrhage requiring transfusion of≥6 red cell concentrate units within 24h of admission. RESULTS: The MH group included 27 patients and the non-MH group included 71 patients. Lactate level, AO/OTA classification and extravasation of computed tomography (CT) contrast fluid had a significantly higher risk as a result of multivariable analysis. The combined score using these risk factors according to their odds-adjusted ratios was created to predict for MH: lactate level>2.5-5.0 (mmol/L)=1 point,>5.0 (mmol/L)=2 points, partially stable (OA/OTA classification B1/B2/B3)=1 point, unstable (C1/C2/C3)=2 points, pelvic extravasation of contrast on CT=4 points. The AUC of the calculated score was 0.93 (95% CI: 0.89-0.98). CONCLUSION: The combined score using these risk factors according to their odds-adjusted ratios was created to predict MH and was an effective prediction score. LEVEL OF EVIDENCE: IV, retrospective study.


Assuntos
Fraturas Ósseas/complicações , Hemorragia/etiologia , Ossos Pélvicos/lesões , Escala Resumida de Ferimentos , Idoso , Área Sob a Curva , Transfusão de Sangue , Estudos de Casos e Controles , Meios de Contraste , Extravasamento de Materiais Terapêuticos e Diagnósticos/etiologia , Feminino , Fraturas Ósseas/classificação , Hemorragia/sangue , Hemorragia/terapia , Humanos , Ácido Láctico/sangue , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Fatores de Risco , Tomografia Computadorizada por Raios X
2.
Orthop Traumatol Surg Res ; 102(8): 1017-1022, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27810321

RESUMO

BACKGROUND: Implantation of Kerboull acetabular reinforcement cross-plates (Kerboull plate) carries a risk for injury to vascular structures and pelvic organs. To our knowledge, there is no study assessing anatomical assessment related to this risk with this specific design. Therefore, we performed a prospective study to answer the following four questions: 1) What is the minimum distance and angle between the plate and iliac vessels? 2) What is the distance between the plate and the inner cortex of the ilium? 3) What is the ratio of views with muscle tissue present on the inner surface of the ilium? 4) What are the boundaries of the safe zone for transacetabular screw fixation for a Kerboull plate? HYPOTHESIS: A safe zone for fixation screws would be defined by a narrow range of insertion angles. MATERIALS AND METHODS: This is a CT-based 3D templating prospective study. Simulations were performed for 18 patients fitted with a Kerboull plate. An original Kerboull plate (Stryker, Mahwah, NJ, USA) was placed at a 45° abduction angle relative to the X-axis (alignment A) and the palette was placed vertically to the X-axis (alignment B). We measured the distance from the centre of the plate to the inner surface of the cortex of the ilium, the shortest distance to vessels and the angle of existing vessels, and the ratio of muscles on the inner surface of the ilium. RESULTS: The shortest distance to the vascular structures increased with increasing angle of insertion of the fixation screws, 85.8±12.1mm for A and 111.4±12.0mm for B at 45°. The distance to the inner cortex was further increased for screws inserted in posterior direction. At insertion angles ≥40°, the screws passed through muscle before invading the pelvis in most cases. However, at anterior-posterior angle (AP angles) ≤-10°, the risk of direct insertion of screws into the sacroiliac joint increased. DISCUSSION: The safe zone for transacetabular screws would be insertion at an angle≥40°, with an AP angle between 0° and -10° (slight posterior direction). LEVEL OF EVIDENCE: Level IV prospective diagnostic study.


Assuntos
Pontos de Referência Anatômicos/diagnóstico por imagem , Artroplastia de Quadril/métodos , Parafusos Ósseos , Implantação de Prótese/métodos , Tomografia Computadorizada por Raios X , Acetábulo/diagnóstico por imagem , Acetábulo/cirurgia , Adulto , Idoso , Artroplastia de Quadril/efeitos adversos , Placas Ósseas , Parafusos Ósseos/efeitos adversos , Simulação por Computador , Feminino , Fixação Interna de Fraturas , Humanos , Artéria Ilíaca/diagnóstico por imagem , Artéria Ilíaca/lesões , Veia Ilíaca/diagnóstico por imagem , Veia Ilíaca/lesões , Ílio/diagnóstico por imagem , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/diagnóstico por imagem , Estudos Prospectivos , Articulação Sacroilíaca/lesões
3.
J Thromb Haemost ; 13 Suppl 1: S133-42, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26149014

RESUMO

Hemophilia is considered suitable for gene therapy because it is caused by a single gene abnormality, and therapeutic coagulation factor levels may vary across a broad range. Recent success of hemophilia B gene therapy with an adeno-associated virus (AAV) vector in a clinical trial showed the real prospect that, through gene therapy, a cure for hemophilia may become a reality. However, AAV-mediated gene therapy is not applicable to patients with hemophilia A at present, and neutralizing antibodies against AAV reduce the efficacy of AAV-mediated strategies. Because patients that benefit from AAV treatment (hemophilia B without neutralizing antibodies) are estimated to represent only 15% of total patients with hemophilia, the development of basic technologies for hemophilia A and those that result in higher therapeutic effects are critical. In this review, we present an outline of gene therapy methods for hemophilia, including the transition of technical developments thus far and our novel techniques.


Assuntos
Terapia Genética/métodos , Hemofilia A/terapia , Hemorragia/terapia , Animais , Coagulação Sanguínea/genética , Dependovirus/genética , Técnicas de Transferência de Genes , Predisposição Genética para Doença , Vetores Genéticos , Hemofilia A/sangue , Hemofilia A/diagnóstico , Hemofilia A/genética , Hemorragia/sangue , Hemorragia/diagnóstico , Hemorragia/genética , Humanos , Fenótipo
4.
Haemophilia ; 20(1): e40-4, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24354485

RESUMO

The use of induced pluripotent stem cells (iPSCs) as an autologous cell source has shed new light on cell replacement therapy with respect to the treatment of numerous hereditary disorders. We focused on the use of iPSCs for cell-based therapy of haemophilia. We generated iPSCs from mesenchymal stem cells that had been isolated from C57BL/6 mice. The mouse iPSCs were generated through the induction of four transcription factor genes Oct3/4, Klf-4, Sox-2 and c-Myc. The derived iPSCs released functional coagulation factor VIII (FVIII) following transduction with a simian immunodeficiency virus vector. The subcutaneous transplantation of iPSCs expressing FVIII into nude mice resulted in teratoma formation, and significantly increased plasma levels of FVIII. The plasma concentration of FVIII was at levels appropriate for human therapy at 2-4 weeks post transplantation. Our data suggest that iPSCs could be an attractive and prospective autologous cell source for the production of coagulation factor, and that engineered iPSCs expressing coagulation factor might provide a cell-based therapeutic strategy appropriate for haemophilia.


Assuntos
Fator VIII/biossíntese , Fator VIII/genética , Vetores Genéticos/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Vírus da Imunodeficiência Símia/genética , Animais , Diferenciação Celular , Células Cultivadas , Expressão Gênica , Ordem dos Genes , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Mesenquimais/citologia , Camundongos , Fatores de Tempo , Transdução Genética
6.
Int J Clin Pract ; 66(10): 999-1008, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22846073

RESUMO

BACKGROUND: Antimicrobial stewardship has not always prevailed in a wide variety of medical institutions in Japan. METHODS: The infection control team was involved in the review of individual use of antibiotics in all inpatients (6348 and 6507 patients/year during the first and second annual interventions, respectively) receiving intravenous antibiotics, according to the published guidelines, consultation with physicians before prescription of antimicrobial agents and organisation of education programme on infection control for all medical staff. The outcomes of extensive implementation of antimicrobial stewardship were evaluated from the standpoint of antimicrobial use density, treatment duration, duration of hospital stay, occurrence of antimicrobial-resistant bacteria and medical expenses. RESULTS: Prolonged use of antibiotics over 2 weeks was significantly reduced after active implementation of antimicrobial stewardship (2.9% vs. 5.2%, p < 0.001). Significant reduction in the antimicrobial consumption was observed in the second-generation cephalosporins (p = 0.03), carbapenems (p = 0.003), aminoglycosides (p < 0.001), leading to a reduction in the cost of antibiotics by 11.7%. The appearance of methicillin-resistant Staphylococcus aureus and the proportion of Serratia marcescens to Gram-negative bacteria decreased significantly from 47.6% to 39.5% (p = 0.026) and from 3.7% to 2.0% (p = 0.026), respectively. Moreover, the mean hospital stay was shortened by 2.9 days after active implementation of antimicrobial stewardship. CONCLUSION: Extensive implementation of antimicrobial stewardship led to a decrease in the inappropriate use of antibiotics, saving in medical expenses, reduction in the development of antimicrobial resistance and shortening of hospital stay.


Assuntos
Anti-Infecciosos/uso terapêutico , Infecção Hospitalar/prevenção & controle , Controle de Infecções/organização & administração , Antibacterianos/administração & dosagem , Antibacterianos/economia , Anti-Infecciosos/economia , Redução de Custos , Infecção Hospitalar/economia , Farmacorresistência Bacteriana , Feminino , Hospitais Universitários , Humanos , Controle de Infecções/economia , Controle de Infecções/métodos , Infusões Intravenosas , Japão , Estimativa de Kaplan-Meier , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Prática Profissional , Procedimentos Desnecessários
7.
J Thromb Haemost ; 10(9): 1802-13, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22784361

RESUMO

BACKGROUND: Transplantation of cells overexpressing a target protein represents a viable gene therapeutic approach for treating hemophilia. Here, we focused on the use of autologous mesenchymal stem cells (MSCs) expressing coagulation factor for the treatment of coagulation factor VIII (FVIII) deficiency in mice. METHODS AND RESULTS: Analysis of luciferase gene constructs driven by different promoters revealed that the plasminogen activator inhibitor-1 (PAI-1) gene promoter coupled with the cytomegalovirus promoter enhancer region was one of the most effective promoters for producing the target protein. MSCs transduced with the simian immunodeficiency virus (SIV) vector containing the FVIII gene driven by the PAI-1 promoter expressed FVIII for several months, and this expression was maintained after multiple mesenchymal lineage differentiation. Although intravenous injection of cell supernatant derived from MSCs transduced with an SIV vector containing the FVIII gene driven by the PAI-1 promoter significantly increased plasma FVIII levels, subcutaneous implantation of the MSCs resulted in a transient and weak increase in plasma FVIII levels in FVIII-deficient mice. Interestingly, intra-articular injection of the transduced MSCs significantly ameliorated the hemarthrosis and hemophilic arthropathy induced by knee joint needle puncture in FVIII-deficient mice. The therapeutic effects of a single intra-articular injection of transduced MSCs to inhibit joint bleeding persisted for at least 8 weeks after administration. CONCLUSIONS: MSCs provide a promising autologous cell source for the production of coagulation factor. Intra-articular injection of MSCs expressing coagulation factor may offer an attractive treatment approach for hemophilic arthropathy.


Assuntos
Fatores de Coagulação Sanguínea/metabolismo , Transplante de Células , Fator VIII/genética , Hemofilia A/terapia , Artropatias/terapia , Células-Tronco Mesenquimais/citologia , Animais , Hemofilia A/complicações , Injeções Intra-Articulares , Artropatias/complicações , Células-Tronco Mesenquimais/metabolismo , Camundongos , Inibidor 1 de Ativador de Plasminogênio/genética , Regiões Promotoras Genéticas
8.
Oncology ; 81(3-4): 273-80, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22122886

RESUMO

OBJECTIVE: The aim of the present study was to retrospectively assess the safety and efficacy of the combination of gemcitabine and nedaplatin in elderly patients with advanced non-small-cell lung cancer (NSCLC). METHODS: Patients ≥75 years with previously untreated NSCLC who underwent chemotherapy consisting of gemcitabine (800 mg/m(2) on days 1 and 8) and nedaplatin (80 mg/m(2) on day 1) every 3 weeks were retrospectively analyzed. RESULTS: Of the 35 patients, 28 were men and 7 were women, with a mean age of 78 years (range 75-87); 10 patients had stage IIIB disease and 25 patients had stage IV disease. The overall response rate was 45.7% (95% confidence interval 28.8-63.4). The median survival time was 14 months (range 3-44). Grade 3-4 toxicities included neutropenia in 74.3%, thrombocytopenia in 48.6%, anemia in 34.3%, hepatic dysfunction in 11.4%, and infection in 2.9%. There were no treatment-related deaths. There were no differences in response rate and survival between patients aged 75-79 years and patients ≥80 years, although grade 3-4 thrombocytopenia and anemia were significantly more frequent in patients ≥80 years. CONCLUSION: Our results suggest that the combination of gemcitabine and nedaplatin is effective and well tolerated for selected elderly patients with advanced NSCLC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/patologia , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/análogos & derivados , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Estadiamento de Neoplasias/métodos , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/efeitos adversos , Estudos Retrospectivos , Análise de Sobrevida , Taxa de Sobrevida , Resultado do Tratamento , Gencitabina
9.
Bone Marrow Transplant ; 46(12): 1557-65, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21258423

RESUMO

Previously, we have shown that IL-21R(-/-) splenocytes ameliorate GVHD as compared with wild-type splenocytes. Here, we investigated whether or not IL-21R(-/-) splenocytes diminish the graft-versus-leukemia (GVL) effect. Surprisingly, IL-21R(-/-) splenocytes efficiently eliminate leukemic cells as well as wild-type splenocytes, suggesting the retention of GVL effects in the absence of IL-21 signaling. To compare the GVL effect between IL-21R(-/-) and wild-type cells, we titrated the number of splenocytes required for the elimination of leukemic cells and found that the threshold of GVL effect was obtained between 5 × 10(5) and 5 × 10(6) with both types of splenocytes. Cotransplantation with CD8-depleted splenocytes but not with purified CD8 T-cells resulted in a significant reduction in anti-leukemic effect of IL-21R(-/-) cells compared with wild-type cells, suggesting that the lack of IL-21 signaling primarily impairs CD4 T-cell rather than CD8 T-cell function and the comparable GVL effect with IL-21R(-/-) bulk splenocytes results from cooperative compensation by CD8 T-cells.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Efeito Enxerto vs Leucemia/imunologia , Interleucinas/imunologia , Leucemia/imunologia , Transdução de Sinais/imunologia , Animais , Efeito Enxerto vs Leucemia/genética , Humanos , Subunidade alfa de Receptor de Interleucina-21/genética , Subunidade alfa de Receptor de Interleucina-21/imunologia , Interleucinas/genética , Interleucinas/metabolismo , Leucemia/genética , Leucemia/terapia , Camundongos , Camundongos Knockout , Transdução de Sinais/genética
10.
Scand J Immunol ; 64(1): 53-60, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16784491

RESUMO

The majority of thymocytes die in the thymus, whereas small populations of T cells that are able to specifically recognize an antigen are considered to survive. Although the thymic selection is thought to have a profound effect on T-cell receptor (TCR) repertoire, little is known how TCR repertoire is formed during the thymocyte developmental process. We examined TCRalpha- and beta-chain variable regions (TCRAV and TCRBV) repertoire in thymic T-cell subpopulations from mice bearing different major histocompatibility (MHC) haplotypes. In Balb/c mice, but not C57BL/6, remarkable alterations of the TCR repertoire were observed in mature T-cell subpopulations as previously reported. In contrast, there were no significant differences of TCRBV repertoire between DN3 (CD25(+)CD44(-)) and DN4 (CD25(-)CD44(-)), and between DN4 and DP. These results suggest that (1) TCR repertoire of mature T cells was formed mainly under the influence of endogenous superantigens, while MHC haplotypes played the least role; (2) the 'beta-selection' process during immature stages had little impact on TCRBV repertoire formation; and (3) TCR repertoire in immature T-cell subpopulations was extremely similar between different strains of mice. We thus consider that pre-selection TCR repertoire in immature T cells could be determined by some genetic factors conserved among different strains.


Assuntos
Receptores de Antígenos de Linfócitos T alfa-beta/genética , Subpopulações de Linfócitos T/imunologia , Timo/citologia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Diferenciação Celular , Deleção Clonal , Feminino , Rearranjo Gênico da Cadeia alfa dos Receptores de Antígenos dos Linfócitos T , Rearranjo Gênico da Cadeia beta dos Receptores de Antígenos dos Linfócitos T , Masculino , Vírus do Tumor Mamário do Camundongo/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase/métodos , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Especificidade da Espécie , Baço/citologia , Subpopulações de Linfócitos T/citologia
11.
J Thromb Haemost ; 4(6): 1271-8, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16706971

RESUMO

OBJECTIVES: Although the concept of aspirin resistance is extensively reported in medical literature, its precise mechanisms and clinical outcomes are largely unknown. In this study, we examined individual thromboxane biosynthesis and platelet aggregation in aspirin-treated patients, and whether the results of a platelet aggregation test influenced clinical outcomes. RESULTS: Subjects taking 81 mg of aspirin (n = 50) and controls (n = 38) were evaluated for platelet aggregation and platelet cyclooxygenase-1 (COX-1) activity by measuring collagen-induced thromboxane B2 production. For aggregometry, both light transmission (LT) and laser-light scattering methods were employed to quantitatively evaluate aggregate sizes and numbers. Aspirin treatment resulted in the inhibition of collagen-induced platelet aggregation, particularly the transition from small to large platelet aggregates. Although platelet COX-1 activity seemed to be uniformly inhibited in all patients, platelet aggregation studies showed great inter-individual differences; variation in platelet COX-1 activity only accounted for 6-20% of the individual aggregations. Factor analysis revealed the existence of a common factor (other than platelet COX-1) that explained 48.4% of the variations in platelet aggregation induced by collagen, adenosine diphosphate (ADP), and collagen-related peptide. We then prospectively enrolled 136 aspirin-treated patients in our study, and we found that being in the upper quartile level of LT, or with large aggregate formation induced by collagen, was an independent risk factor for developing cardiovascular events within 12 months [hazard ratio (HR) = 7.98, P = 0.008 for LT; HR = 7.76, P = 0.007 for large aggregates]. On the other hand, the existence of diabetes mellitus was an independent risk factor for overall outcomes (HR 1.30-11.9, P = 0.015-0.033). CONCLUSIONS: Aspirin resistance expressed as unsuppressed platelet COX-1 activity is a rare condition in an out-patient population. Other factor(s) affecting collagen-induced platelet aggregation may influence early outcomes in aspirin-treated patients.


Assuntos
Aspirina/farmacologia , Plaquetas/efeitos dos fármacos , Doenças Cardiovasculares/sangue , Inibidores de Ciclo-Oxigenase/farmacologia , Resistência a Medicamentos , Inibidores da Agregação Plaquetária/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Idoso , Aspirina/efeitos adversos , Plaquetas/enzimologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/urina , Colágeno/farmacologia , Ciclo-Oxigenase 1/metabolismo , Inibidores de Ciclo-Oxigenase/efeitos adversos , Feminino , Humanos , Masculino , Inibidores da Agregação Plaquetária/efeitos adversos , Testes de Função Plaquetária/métodos , Estudos Prospectivos , Fatores de Risco , Transdução de Sinais , Tromboxano B2/análogos & derivados , Tromboxano B2/metabolismo , Tromboxano B2/urina , Resultado do Tratamento
12.
J Neuropsychiatry Clin Neurosci ; 17(2): 239-42, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15939980

RESUMO

The authors tested the hypothesis that estradiol would be associated with negative symptoms in 30 male schizophrenia inpatients. Medications were switched from typical to atypical antipsychotics. Estradiol concentrations were inversely correlated with negative symptoms significantly before the switch and at a trend level of significance after the switch. Changes in negative symptoms were positively correlated with those in estradiol concentrations at a trend level of significance. Estradiol could be a biological marker for negative symptoms even in male schizophrenia patients.


Assuntos
Esquizofrenia/sangue , Psicologia do Esquizofrênico , Adulto , Antipsicóticos/uso terapêutico , Biomarcadores , Estradiol/sangue , Humanos , Pacientes Internados , Masculino , Estudos Prospectivos , Escalas de Graduação Psiquiátrica , Esquizofrenia/tratamento farmacológico
13.
Br J Cancer ; 92(8): 1486-92, 2005 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-15798770

RESUMO

KRN 8602 (MX2) is a novel morpholino anthracycline derivative having the chemical structure 3'-deamino-3'-morpholino-13-deoxo-10-hydroxycarminomycin hydrochloride. To investigate the mechanisms of resistance to MX2, we established an MX2-resistant phenotype (K562/MX2) of the human myelogeneous leukaemia cell line (K562/P), by continuously exposing a suspension culture to increasing concentrations of MX2. K562/MX2 cells were more resistant to MX2 than the parent cells, and also showed cross-resistance to etoposide and doxorubicin. Topoisomerase (Topo) IIalpha protein levels in K562/MX2 cells were lower of those in K562/P cells on immunoblot analysis and decreased expression of Topo IIalpha mRNA was seen in K562/MX2 cells. Topoisomerase II catalytic activity was also reduced in the nuclear extracts from K562/MX2 cells when compared with K562/P cells. Aberrant methylated CpG of Topo IIalpha gene was observed in K562/MX2 cells when compared with the parent line on methylation-specific restriction enzyme analysis. To overcome the drug resistance to MX2 and etoposide, we investigated treatment with 5-Aza-2'-deoxycytidine (5AZ), which is a demethylating agent, in K562/MX2 cells. 5-Aza-2'-deoxycytidine treatment increased Topo IIalpha mRNA expression in K562/MX2 cells, but not in K562/P cells, and increased the cytotoxicity of MX2 and etoposide. Methylated CpG was decreased in K562/MX2 cells after 5AZ treatment. We concluded that the mechanism of drug resistance to MX2 and etoposide in K562/MX2 cells might be the combination of decreased expression of Topo IIalpha gene and increased methylation, and that 5AZ could prove to be a novel treatment for etoposide-resistant cell lines, such as K562/MX2.


Assuntos
Antígenos de Neoplasias/biossíntese , Antineoplásicos/farmacologia , Azacitidina/análogos & derivados , Carrubicina/análogos & derivados , Carrubicina/farmacologia , Metilação de DNA , DNA Topoisomerases Tipo II/biossíntese , Proteínas de Ligação a DNA/biossíntese , Resistencia a Medicamentos Antineoplásicos , Etoposídeo/farmacologia , Antígenos de Neoplasias/efeitos dos fármacos , Azacitidina/farmacologia , Northern Blotting , Linhagem Celular Tumoral , Ilhas de CpG/genética , Metilação de DNA/efeitos dos fármacos , DNA Topoisomerases Tipo II/efeitos dos fármacos , Proteínas de Ligação a DNA/efeitos dos fármacos , Decitabina , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Citometria de Fluxo , Humanos , Immunoblotting , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Dev Dyn ; 222(2): 178-91, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11668596

RESUMO

Stratum intermedium is a transient and subtle epithelial structure closely associated with inner dental epithelium in tooth germs. Little is known about its development and roles. To facilitate analysis, we used bovine tooth germs, predicting that they may contain a more conspicuous stratum intermedium. Indeed, early bell stage bovine tooth germs already displayed an obvious stratum intermedium with a typical multilayered organization and flanking the enamel knot. Strikingly, with further development, the cuspally located stratum intermedium underwent thinning and involution, whereas a multilayered stratum intermedium formed at successive sites along the cusp-to-cervix axis of odontogenesis. In situ hybridization and immunohistochemistry showed that stratum intermedium produces the signaling molecule Sonic hedgehog (Shh). Maximal Shh expression was invariably seen in its thickest multilayered portions. Shh was also produced by inner dental epithelium; expression was not constant but varied with development and cytodifferentiation of ameloblasts along the cusp-to-cervix axis. Interestingly, maximal Shh expression in inner dental epithelium did not coincide with that in stratum intermedium. Both stratum intermedium and inner dental epithelium expressed the Shh receptor Patched2 (Ptch2), an indication of autocrine signaling loops. Shh protein, but not RNA, was present in underlying dental mesenchyme, probably resulting from gradual diffusion from epithelial layers and reflecting paracrine loops of action. To analyze the regulation of Shh expression, epithelial and mesenchymal layers were separated and maintained in organ culture. Shh expression decreased over time, but was maintained in unoperated specimens. Our data show for the first time that stratum intermedium is a highly regulated and Shh-expressing structure. Given its dynamic and apparently interactive properties, stratum intermedium may help orchestrate progression of odontogenesis from cusp to cervix.


Assuntos
Odontogênese/fisiologia , Transdução de Sinais/fisiologia , Transativadores/genética , Fator de Crescimento Transformador beta , Animais , Proteína Morfogenética Óssea 2 , Proteína Morfogenética Óssea 4 , Proteínas Morfogenéticas Ósseas/genética , Bovinos , Comunicação Celular/fisiologia , Ensaio de Imunoadsorção Enzimática , Células Epiteliais/citologia , Regulação da Expressão Gênica no Desenvolvimento , Proteínas Hedgehog , Proteínas de Membrana/genética , Mesoderma/citologia , RNA Mensageiro/análise , Germe de Dente/química , Germe de Dente/embriologia , Transativadores/análise
17.
J Cell Biol ; 153(1): 87-100, 2001 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-11285276

RESUMO

During skeletogenesis, cartilage develops to either permanent cartilage that persists through life or transient cartilage that is eventually replaced by bone. However, the mechanism by which cartilage phenotype is specified remains unclarified. Core binding factor alpha1 (Cbfa1) is an essential transcription factor for osteoblast differentiation and bone formation and has the ability to stimulate chondrocyte maturation in vitro. To understand the roles of Cbfa1 in chondrocytes during skeletal development, we generated transgenic mice that overexpress Cbfa1 or a dominant negative (DN)-Cbfa1 in chondrocytes under the control of a type II collagen promoter/enhancer. Both types of transgenic mice displayed dwarfism and skeletal malformations, which, however, resulted from opposite cellular phenotypes. Cbfa1 overexpression caused acceleration of endochondral ossification due to precocious chondrocyte maturation, whereas overexpression of DN-Cbfa1 suppressed maturation and delayed endochondral ossification. In addition, Cbfa1 transgenic mice failed to form most of their joints and permanent cartilage entered the endochondral pathway, whereas most chondrocytes in DN-Cbfa1 transgenic mice retained a marker for permanent cartilage. These data show that temporally and spatially regulated expression of Cbfa1 in chondrocytes is required for skeletogenesis, including formation of joints, permanent cartilages, and endochondral bones.


Assuntos
Proteínas Morfogenéticas Ósseas , Osso e Ossos/anormalidades , Condrócitos/fisiologia , Proteínas de Neoplasias , Osteogênese/fisiologia , Fatores de Transcrição/fisiologia , Animais , Cartilagem/metabolismo , Células Cultivadas , Galinhas , Condrócitos/citologia , Subunidade alfa 1 de Fator de Ligação ao Core , Fatores de Ligação ao Core , Expressão Gênica , Fator 5 de Diferenciação de Crescimento , Substâncias de Crescimento/genética , Articulações/metabolismo , Camundongos , Camundongos Transgênicos , Tenascina/genética , Fatores de Transcrição/genética
18.
J Biol Chem ; 276(7): 5274-80, 2001 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-11056155

RESUMO

Since blood platelets release sphingosine 1-phosphate (Sph-1-P) upon activation, it is important to examine the effects of this bioactive lipid on vascular endothelial cell functions from the viewpoint of platelet-endothelial cell interactions. In the present study, we examined Sph-1-P-stimulated signaling pathways related to human umbilical vein endothelial cell (HUVEC) motility, with a special emphasis on the cytoskeletal docking protein Crk-associated substrate (Cas). Sph-1-P stimulated tyrosine phosphorylation of Cas, which was inhibited by the G(i) inactivator pertussis toxin but not by the Rho inactivator C3 exoenzyme or the Rho kinase inhibitor Y-27632. Fyn constitutively associated with and phosphorylated Cas, suggesting that Cas tyrosine phosphorylation may be catalyzed by Fyn. Furthermore, upon HUVEC stimulation with Sph-1-P, Crk, through its SH2 domain, interacted with tyrosine-phosphorylated Cas, and the Cas-Crk complex translocated to the cell periphery (membrane ruffles), through mediation of G(i) (Fyn) but not Rho. In contrast, tyrosine phosphorylation of focal adhesion kinase, and formation of stress fibers and focal adhesion were mediated by Rho but not G(i) (Fyn). Finally, Sph-1-P-enhanced HUVEC motility, assessed by a phagokinetic assay using gold sol-coated plates and a Boyden's chamber assay, was markedly inhibited not only by pertussis toxin (or the Fyn kinase inhibitor PP2) but also by C3 exoenzyme (or Y-27632). In HUVECs stimulated with Sph-1-P, these data suggest the following: (i) cytoskeletal signalings may be separable into G(i)-mediated signaling pathways (involving Cas) and Rho-mediated ones (involving FAK), and (ii) coordinated signalings from both pathways are required for Sph-1-P-enhanced HUVEC motility. Since HUVECs reportedly express the Sph-1-P receptors EDG-1 (coupled with G(i)) and EDG-3 (coupled with G(13) and G(q)) and the EDG-3 antagonist suramin was found to block specifically Rho-mediated responses, it is likely that Cas-related responses following G(i) activation originate from EDG-1, whereas Rho-related responses originate from EDG-3.


Assuntos
Toxinas Botulínicas , Movimento Celular , Endotélio Vascular/metabolismo , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/fisiologia , Lisofosfolipídeos , Proteínas/metabolismo , Esfingosina/farmacologia , ADP Ribose Transferases/farmacologia , Membrana Celular/metabolismo , Membrana Celular/ultraestrutura , Células Cultivadas , Proteína de Suscetibilidade a Apoptose Celular , Citoesqueleto/metabolismo , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/ultraestrutura , Humanos , Toxina Pertussis , Fosforilação , Fosfotirosina/metabolismo , Transporte Proteico , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas/fisiologia , Proteínas Proto-Oncogênicas c-crk , Proteínas Proto-Oncogênicas c-fyn , Transdução de Sinais , Esfingosina/análogos & derivados , Suramina/farmacologia , Fatores de Virulência de Bordetella/farmacologia , Proteína rhoA de Ligação ao GTP/fisiologia
19.
Glycoconj J ; 18(8): 635-40, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12376728

RESUMO

Comparison of oligosaccharide components derived from salivary mucin was performed between secretor and non-secretor individuals. Salivary mucin was collected from four secretors and three non-secretors having blood group type-A. Compositional analysis showed that the contents of galactose and N-acetylglucosamine in the non-secretor were higher than those in the secretor. The O-linked oligosaccharides obtained by treatment with alkaline borohydride were separated by gel filtration using Sephadex G-50. The results indicated that the size of the type-A active oligosaccharides from the secretor was similar to or smaller than that of the non-secretor. Ion-exchange chromatography showed that the secretors had strong type-A activities in both the neutral and acidic fractions but the non-secretors showed type-A activity mainly in the neutral fraction. These results suggest that compositional differences in blood group substances exist between secretors and non-secretors.


Assuntos
Sistema ABO de Grupos Sanguíneos , Mucinas/química , Oligossacarídeos/química , Saliva/metabolismo , Amino Açúcares/análise , Amino Açúcares/química , Cromatografia em Gel , Cromatografia por Troca Iônica , Ensaio de Imunoadsorção Enzimática , Humanos , Japão , Antígenos do Grupo Sanguíneo de Lewis , Monossacarídeos/análise , Monossacarídeos/química , Mucinas/isolamento & purificação , Oligossacarídeos/análise , Fenótipo
20.
Pathol Int ; 50(8): 660-6, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10972866

RESUMO

This is a report of a post-mortem histological, histochemical, and immunohistochemical examination of a rare case of sclerosing encapsulating peritonitis (SEP) and non-occlusive mesenteric infarction (NOMI), two serious complications of continuous ambulatory peritoneal dialysis (CAPD), with which a man suffering hepatitis C virus (HCV)-induced liver cirrhosis for 7 years and trauma-induced paraplegia for 50 years had been treated for 1 year. The direct cause of death was encephalopathy caused by extreme hyperammonemia (11 250 microg/dL in serum). The autopsy revealed that the SEP had drastically reduced the length of the small intestine to 210 cm, 180 cm of which presented acute ischemic enteritis with Gram-negative bacterial infection. Histological examination of the SEP revealed that the exterior was composed of normal serosal elastic lamina, but with a cocoon-like appearance remarkably thickened by fibrosis to 3-8 times that of the normal subserosal layer and consisting of spindle cells and blood vessels, with some infiltration of mast cells and lymphocytes. The immunohistochemical examination of the spindle cells revealed few AE1/AE3(+) cells, HHF35(+) cells, and CD34(+) cells, many CD117(+) cells with slight proliferative activity based on MIB-1 positivity (proliferation index <1%), but no CD44(+) cells. It was concluded that either the few CD34(+) and/or the many CD117(+) cells were mesenteric stem cells that had originated from the serosa, proliferated, then differentiated into myofibroblasts or fibroblasts, producing collagen and hyaluronic acid in the matrix, leading to the gradual formation of the SEP, which was induced by the continual irritation of CAPD.


Assuntos
Infarto/etiologia , Mesentério/irrigação sanguínea , Diálise Peritoneal Ambulatorial Contínua/efeitos adversos , Peritonite/etiologia , Esclerose/etiologia , Idoso , Antígenos CD34/metabolismo , Biomarcadores , Divisão Celular , Evolução Fatal , Histocitoquímica , Humanos , Técnicas Imunoenzimáticas , Infarto/metabolismo , Infarto/patologia , Obstrução Intestinal/etiologia , Obstrução Intestinal/patologia , Intestino Delgado/metabolismo , Intestino Delgado/patologia , Masculino , Mesentério/patologia , Peritonite/metabolismo , Peritonite/patologia , Proteínas Proto-Oncogênicas c-kit/metabolismo , Esclerose/metabolismo , Esclerose/patologia
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