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1.
Tech Coloproctol ; 23(10): 973-980, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31535238

RESUMEN

BACKGROUND: Anastomotic leakage (AL) is one of the most troublesome complications in colorectal surgery. Recently, near-infrared fluorescence (NIRF) imaging has been used intraoperatively to detect sentinel lymph nodes and visualize the blood supply at the region of interest (ROI). The aim of this study was to evaluate the role of visualization and quantification of bowel perfusion around the anastomosis using NIRF system in predicting AL. METHODS: A prospective study was conducted on patients who had laparoscopic surgery for colorectal cancer at our institution. Perfusion of the anastomosis was evaluated with NIRF imaging after intravenous injection of indocyanine green (ICG). The time course of fluorescence intensity was recorded by an imaging analyzer We measured the time from ICG injection to the beginning of fluorescence (T0), maximum intensity (Imax), time to reach Imax (Tmax), time to reach Imax 50% ([Formula: see text]) and slope (S) after the anastomosis. RESULTS: Tumor locations were as follows; cecum: 2, ascending colon: 2, transverse colon: 7, descending colon: 1, sigmoid colon: 2, rectosigmoid colon: 3 and rectum: 6 (one case with synchronous cancer). All operations were performed laparoscopically. Four patients were diagnosed with or suspected to have AL (2 patients with grade B anastomotic leakage after low anterior resection, 1 patient with minor leakage in transverse colon resection and 1 patient needing re-anastomosis intraoperatively in transverse colon resection). T0 was significantly longer in the AL group than in patients without AL (64.3 ± 27.6 and 18.2 ± 6.6 s, p = 2.2 × 10-3). CONCLUSIONS: Perfusion of the anastomosis could be successfully visualized and quantified using NIRF imaging with ICG. T0 might be a useful parameter for prediction of AL.


Asunto(s)
Fuga Anastomótica/diagnóstico por imagen , Neoplasias Colorrectales/cirugía , Cuidados Intraoperatorios/métodos , Imagen de Perfusión/métodos , Estomas Quirúrgicos/irrigación sanguínea , Anciano , Anciano de 80 o más Años , Anastomosis Quirúrgica/efectos adversos , Anastomosis Quirúrgica/métodos , Fuga Anastomótica/etiología , Colectomía/efectos adversos , Colectomía/métodos , Colon/irrigación sanguínea , Colon/diagnóstico por imagen , Colon/cirugía , Colorantes , Femenino , Fluorescencia , Humanos , Verde de Indocianina , Rayos Infrarrojos , Laparoscopía/efectos adversos , Laparoscopía/métodos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Recto/irrigación sanguínea , Recto/diagnóstico por imagen , Recto/cirugía , Estomas Quirúrgicos/efectos adversos
2.
Am J Transplant ; 15(10): 2565-75, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26012352

RESUMEN

Unpreventable allograft rejection is one of the main problems in pancreatic islet transplantation (PIT). Therefore, it is imperative to develop a more effective immunosuppressive strategy. The blockade of transcription factors has been a central part of T cell-depleting immunosuppressive therapies, as typified by the use of calcineurin inhibitors. The inhibition of activator protein-1 (AP-1) offers a novel strategy for immunosuppression in PIT, although to date, no reports on the effects of AP-1 inhibition are available. In this study, we investigated the immunosuppressive effects of T-5224, a c-Fos/AP-1-selective inhibitor, on murine T cells activated by αCD3+αCD28 mAbs. T-5224 inhibited proliferation, CD25 up-regulation, and the production of IL-2 and interferon-γ. In addition, T-5224 blocked the nuclear translocation of c-Fos/AP-1 in activated murine T cells. In BALB/c (H-2(d) )-to-C57BL/6J (H-2(b) ) mouse PIT, the 2-week administration of T-5224 prolonged survival of 600 islet allografts in a dose-dependent manner. When combined with a 2-week low-dose tacrolimus, the T-5224 treatment markedly prolonged allograft survival to over 300 days, while the efficacy was indeterminate when transplanted islet allograft mass was reduced to 300. We conclude that the c-Fos/AP-1 inhibition by T-5224 is a potentially attractive strategy for allogeneic PIT.


Asunto(s)
Benzofenonas/uso terapéutico , Rechazo de Injerto/prevención & control , Inmunosupresores/uso terapéutico , Trasplante de Islotes Pancreáticos/inmunología , Isoxazoles/uso terapéutico , Animales , Benzofenonas/farmacología , Rechazo de Injerto/inmunología , Inmunosupresores/farmacología , Isoxazoles/farmacología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Proteínas Proto-Oncogénicas c-fos/antagonistas & inhibidores , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Linfocitos T/metabolismo , Factor de Transcripción AP-1/antagonistas & inhibidores , Trasplante Homólogo
3.
Br J Surg ; 101(9): 1084-91, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24975853

RESUMEN

BACKGROUND: Pancreaticoduodenectomy (PD) is associated with a high incidence of postoperative complications including pancreatic fistula. This randomized clinical trial compared the incidence of pancreatic fistula between the isolated Roux-en-Y (IsoRY) and conventional reconstruction (CR) methods. METHODS: Patients admitted for PD between June 2009 and September 2012 in a single centre were assigned randomly to CR or IsoRY. The primary endpoint was the incidence of pancreatic fistula (grade A-C) defined according to the International Study Group on Pancreatic Fistula. Secondary endpoints were complication rates, mortality and hospital stay. Multiple logistic regression analysis was performed to identify factors associated with pancreatic fistula. RESULTS: Some 153 patients were randomized, 76 to CR and 77 to IsoRY; two patients from the IsoRY group were excluded after randomization. Pancreatic fistula occurred in 26 patients (34 per cent) in the CR group and 25 (33 per cent) in the IsoRY group (P = 0·909). The number of patients with a clinically relevant pancreatic fistula (grade B or C) was similar in the two groups (10 and 11 patients respectively; P = 0·789), as were complication rates (42 versus 40 per cent; P = 0·793) and mortality (none in either group; P = 0·999). Soft pancreas was the only independent risk factor for pancreatic fistula (odds ratio 4·42, 95 per cent confidence interval 1·85 to 10·53; P <0·001). CONCLUSION: This study showed that IsoRY reconstruction does not reduce the incidence of pancreatic fistula compared with CR. REGISTRATION NUMBER: NCT00915863 (http://www.clinicaltrials.gov/) and UMIN000001967 (http://www.umin.ac.jp/).


Asunto(s)
Fístula Pancreática/etiología , Pancreaticoduodenectomía/métodos , Anciano , Anastomosis en-Y de Roux/efectos adversos , Anastomosis en-Y de Roux/métodos , Femenino , Humanos , Masculino , Análisis Multivariante , Pancreaticoduodenectomía/efectos adversos , Complicaciones Posoperatorias/etiología , Medición de Riesgo , Factores de Riesgo
4.
Mini Rev Med Chem ; 12(6): 505-14, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22587765

RESUMEN

Quantitative structure-activity relationship (QSAR) analysis is a practical approach by which chemical structure is quantitatively correlated with biological activity or chemical reactivity. Human ABC transporter ABCG2 exhibits broad substrate specificity toward structurally diverse compounds. To gain insight into the relationship between the molecular structures of compounds and the interaction with ABCG2, we have developed an algorithm that analyzes QSAR to evaluate ABCG2-drug interactions. In addition, to support QSAR analysis, we developed a high-speed screening method for analyzing the drug-drug interactions of ABCG2. Based on both experimental results and computational QSAR analysis data, we propose a hypothetical mechanism underlying ABC-mediated drug transport and its interaction with drugs.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/metabolismo , Proteínas de Neoplasias/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Algoritmos , Humanos , Relación Estructura-Actividad Cuantitativa
5.
Biochem Biophys Res Commun ; 289(1): 205-11, 2001 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-11708800

RESUMEN

Hepatocyte growth factor activator inhibitor type 1 (HAI-1), a Kunitz-type serine protease inhibitor for hepatocyte growth factor activator (HGFA), is responsible for proteolytic activation of hepatocyte growth factor. We examined the expression of HGFA and HAI-1 in liver tissues of chronic liver diseases including hepatocellular carcinoma (HCC). HGFA expression was detected not only in the liver tissues of chronic hepatitis and cirrhosis and in the nontumorous liver tissues surrounding HCC, but also in HCC tissues. On the other hand, none of the liver tissues of hepatitis and cirrhosis and none of the nontumorous tissues surrounding HCC were stained with anti-HAI-1. However, 35% of HCC tissues were stained with anti-HAI-1, and HAI-1 positivity increased as the histological grade decreased and as serum alpha-fetoprotein increased. Transduction of antisense HAI-1 inhibited the growth of human hepatoma cells. These results suggest the possibility that HAI-1 plays an important role in the progression of HCC.


Asunto(s)
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Serina Endopeptidasas/genética , Serina Endopeptidasas/metabolismo , Secuencia de Bases , Carcinoma Hepatocelular/patología , División Celular , Cartilla de ADN/genética , ADN sin Sentido/genética , Expresión Génica , Hepatitis Crónica/genética , Hepatitis Crónica/metabolismo , Humanos , Hígado/metabolismo , Cirrosis Hepática/genética , Cirrosis Hepática/metabolismo , Neoplasias Hepáticas/patología , Proteínas Inhibidoras de Proteinasas Secretoras , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , Transducción Genética , Células Tumorales Cultivadas
6.
Jpn Circ J ; 65(8): 711-6, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11502047

RESUMEN

Mechanical alternans has been observed in patients with severe congestive heart failure, and the phenomenon is considered to be a terminal sign. Therapeutic strategies for chronic heart failure have significantly developed, but it is uncertain whether patients with mechanical alternans can be effectively treated or not. Seventeen consecutive patients with dilated cardiomyopathy were enrolled: 11 were treated with beta-blockers on conventional therapeutic regimens and 6 patients were not indicated for or were unable to continue beta-blockade. Mechanical alternans was detected during cardiac catheterization in the patients under physiologic tachycardia (110 beats/min) and stepwise dobutamine loading. In the initial study, mechanical alternans occurred in 70.6% of the patients: 8 of the 11 being treated with beta-blockers and 4 of the 6 without beta-blockade therapy. In the second study, none of the patients taking beta-blockers showed mechanical alternans under the same protocol; the occurrence of mechanical alternans did not change in the patients who were not being treated with beta-blockers. The left ventricular ejection fraction increased in patients whose mechanical alternans could not be induced during the follow up, but decreased in the patients in whom mechanical alternans was repeatedly inducible. It is concluded that mechanical alternans is associated with the failing myocardium and may be potentially correctable.


Asunto(s)
Antagonistas Adrenérgicos beta/administración & dosificación , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/fisiopatología , Adulto , Anciano , Cateterismo Cardíaco , Cardiomiopatía Dilatada/tratamiento farmacológico , Cardiomiopatía Dilatada/fisiopatología , Femenino , Hemodinámica/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Taquicardia/etiología , Función Ventricular Izquierda/fisiología
7.
Yakugaku Zasshi ; 121(8): 621-9, 2001 Aug.
Artículo en Japonés | MEDLINE | ID: mdl-11523122

RESUMEN

Vancomycin hydrochloride (VCM) is widely used for treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections. However, this drug can cause sever adverse reactions, such as red neck syndrome, nephrotoxicity and ototoxicity. Thus, therapeutic drug monitoring (TDM) was bringing into effect for well effectiveness and to prevent side effects. In Kanto Medical Center NTT EC, TDM of VCM has been brought into effect since 1994. The date were accumulated from 200 patients. In this study, the retrospective research was carried out based on 117 cases selected from the above accumulated data, and then several factors such as VCM inducing side effect, a therapeutic effect, and the forecast of pharmacokinetic parameter using laboratory data were examined. Consequently, the high blood concentration trough level, the high value after 1 to 2 hours infusion, and the extension of t1/2 were brought forward as a nephrotoxicity causing factor, and more over each laboratory data (BUN, Cr, GOT, GPT, gamma-GTP, T-BiL, ALP, LDH) was high before infusion of VCM in patients with renal dysfunction. High value T-Bil and lower value TP were brought forward in patients with hepatic dysfunction, and high eosinophils and high blood concentration were brought forward after 1 or 2 hours infusion. In relation to side effects, it was found that the outbreak rate of side effects is high in patients with a complication of hypertension or diabetes. The administration term was considered as a factor which influences the therapeutic effects. The unchanged effect was 10.9 +/- 7.9 days, the improved effect was 14.6 +/- 9.3 days, the remarkably improved effect was 17.7 +/- 14.1 days. As the administration term gets longer, the improvement rate was recognized to be an upward tendency. The difference in significant effects was recognized between unchanged and remarkably unchanged (p < 0.05) effects. As the forecast of pharmacokinetic parameter using the laboratory data, VCMt1/2 showed a significant correlation between Cr and T-BiL, and it was VCMt1/2 = 8.56CR + 2.169T-Bil + 7.1. This result shows that VCMt1/2 can be estimated.


Asunto(s)
Infecciones Estafilocócicas/tratamiento farmacológico , Vancomicina/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad Hepática Inducida por Sustancias y Drogas , Femenino , Humanos , Enfermedades Renales/inducido químicamente , Enfermedades Renales/epidemiología , Hepatopatías/epidemiología , Masculino , Resistencia a la Meticilina , Persona de Mediana Edad , Estudios Retrospectivos , Equivalencia Terapéutica , Resultado del Tratamiento , Vancomicina/efectos adversos , Vancomicina/farmacocinética
8.
Drug Des Discov ; 17(3): 265-81, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11469756

RESUMEN

The success or failure of 3D QSAR, particularly CoMFA, is most strongly dependent, especially for flexible compounds, on the conformation of the molecule used in the analysis, and on the orientation of the molecule relative to the other molecules in 3D space (i.e., alignment). The present study suggests a rational procedure for the estimation of binding conformation that uses the transferred nuclear Overhauser effect (TRNOE) experiment in combination with conformational analysis using CAMDAS (Conformational Analyzer with Molecular Dynamics And Sampling) program that is developed in our laboratory. In the next step the TRNOE-obtained conformation can be used as a reference template in order to obtain alignment of other ligands, that have a common binding site. In this step we used the SUPERPOSE program created in our laboratory, in order to estimate the binding conformation of other compounds, and to simultaneously obtain the alignment of compounds for CoMFA. The resulting CoMFA models could be expected to closely reproduce the interaction mode with protein represented by the reported X-ray results. In order to confirm the validity of our procedure described above, we show its application in obtaining CoMFA models of thermolysin inhibitors. We obtained twenty CoMFA models, and that with the highest q2 value (q2 = 0.701) was found to provide an interaction mode very similar to that represented by the X-ray results.


Asunto(s)
Relación Estructura-Actividad Cuantitativa , Termolisina/antagonistas & inhibidores , Conformación Molecular
9.
Clin Exp Immunol ; 124(3): 346-52, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11472393

RESUMEN

Monocyte chemoattractant protein-1 (MCP-1) is a member of the C-C chemokine family that has been shown to play a major role in the migration of monocytes and T cells to an inflammatory focus. To clarify the role of MCP-1 in the pathogenesis of myocarditis, we have examined the expression of MCP-1 in rat hearts with experimental autoimmune myocarditis (EAM), and have also measured serum levels of MCP-1 in patients with histology-proven acute myocarditis. Lewis rats were immunized with cardiac myosin and were killed 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 42 and 56 days after immunization. Large mononuclear cells in the myocardial interstitium were stained with an anti-MCP-1 antibody. mRNA of MCP-1 increased in the hearts of EAM rats from days 15--27 as shown by quantitative reverse transcription-polymerase chain reaction. Serum MCP-1 levels of the rats with EAM were significantly elevated from days 15--24. In the clinical study, serum levels of MCP-1 in 24 patients with acute myocarditis at the time of admission (165.2 +/- 55.8 pg/ml) were significantly (P = 0.0301) elevated compared with those of 20 healthy volunteers (61.8 +/- 10.7 pg/ml). Serum MCP-1 levels of 8 fatal cases (371.8 +/- 145.2 pg/ml) were significantly (P = 0.0058) higher than those of 16 cases who survived (65.5 +/- 12.8 pg/ml). In conclusions, MCP-1 may play an important role in the pathogenesis of human acute myocarditis as well as in the progression of rat EAM.


Asunto(s)
Quimiocina CCL2/sangre , Miocarditis/inmunología , Enfermedad Aguda , Animales , Quimiocina CCL2/biosíntesis , Quimiocina CCL2/genética , Modelos Animales de Enfermedad , Expresión Génica , Humanos , Inmunohistoquímica/métodos , Miocarditis/sangre , Miocardio/patología , ARN Mensajero , Ratas , Ratas Endogámicas Lew
10.
J Card Fail ; 7(2): 138-45, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11420765

RESUMEN

BACKGROUND: Clinical implications of mechanical alternans in patients with chronic heart failure have remained uncertain. In this study, prevalence, characteristics, and prognostic implications of mechanical alternans were investigated. METHODS AND RESULTS: Consecutive 51 patients with dilated cardiomyopathy underwent diagnostic cardiac catheterization using a micromanometer-tipped catheter. Under basal conditions, 7 of 35 patients with sinus rhythm showed mechanical alternans. Physiologic tachycardia (110 bpm) induced mechanical alternans in another 15 patients with sinus rhythm and in another 10 of 16 patients with atrial fibrillation. Low doses of dobutamine also induced mechanical alternans in another 8 patients, but a high dose of dobutamine eliminated mechanical alternans. Consequently, 40 patients (78%) showed mechanical alternans. Mechanical alternans was always accompanied by alternating changes of positive dP/dt, a parameter of contractility during isovolumetric contraction time, but negative dP/dt was occasionally constant. Concordant mechanical alternans between both ventricles was more prevalent than discordant alternans. The left ventricular end-diastolic volume indices and end-systolic volume indices of patients with mechanical alternans were larger than those of patients without. The left ventricular ejection fraction of patients with alternans was significantly lower than that of patients without. CONCLUSIONS: Mechanical alternans was highly prevalent in patients with chronic heart failure. The origin of mechanical alternans seems to exist before or at the isovolumetric contraction time.


Asunto(s)
Arritmias Cardíacas/complicaciones , Arritmias Cardíacas/fisiopatología , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/fisiopatología , Función Ventricular Izquierda/fisiología , Adulto , Anciano , Enfermedad Crónica , Femenino , Hemodinámica/fisiología , Humanos , Masculino , Persona de Mediana Edad , Contracción Miocárdica/fisiología , Pronóstico
11.
Hepatology ; 33(6): 1441-50, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11391533

RESUMEN

D-Galactosamine (GalN)/lipopolysaccharide (LPS)-induced liver injury is an experimental model of fulminant hepatic failure in which tumor necrosis factor alpha (TNF-alpha) plays a pivotal role. We examined the effects of etoposide on GalN/LPS-induced fulminant hepatic failure. Mice were given an intraperitoneal dose of GalN (800 microg/g body weight)/LPS (100 ng/g body weight) with and without intraperitoneal etoposide (10 microg/g body weight) treatment. Liver injury was assessed biochemically and histologically. TNF-alpha levels in the serum, and apoptosis of hepatocytes and CPP32/caspase-3 in the liver, were determined. GalN/LPS treatment caused lethal liver injury in 87% of animals (13 of 15). The effect was associated with significant increases in TNF-alpha and alanine transaminase (ALT) levels in serum, the number of apoptotic hepatocytes, CPP32/caspase-3 activity, and TNF receptor 1 (TNFR1) mRNA expression in the liver. Etoposide (10 microg/g body weight) was given 3 times (at 50, 26, and 4 hours before GalN/LPS administration). Treatment of GalN/LPS-treated mice with etoposide reduced apoptosis of hepatocytes, resulting in reduction of lethality (13% [2 of 15]), while another topoisomerase II inhibitor, IRCF-193, showed no significant effect. The antilethal effect of etoposide was also confirmed in GalN/TNF-alpha-induced fulminant hepatic failure. Etoposide treatment reduced CPP32/caspase-3 activity in the liver, although it did not alter the serum TNF-alpha levels or hepatic TNFR1 mRNA expressions. In addition, etoposide treatment enhanced the mRNA and protein expression of Bcl-xL, an antiapoptotic molecule in the liver. The present findings suggest that etoposide prevents endotoxin-induced lethal liver injury by up-regulation of Bcl-xL, and that etoposide could be useful for the treatment of TNF-alpha-mediated liver diseases.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Etopósido/farmacología , Fallo Hepático/mortalidad , Fallo Hepático/fisiopatología , Hígado/efectos de los fármacos , Hígado/fisiopatología , Animales , Antígenos CD/genética , Caspasa 3 , Inhibidores de Caspasas , Grupo Citocromo c/antagonistas & inhibidores , Citoplasma/metabolismo , Galactosamina , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Lipopolisacáridos , Hígado/metabolismo , Hígado/patología , Fallo Hepático/inducido químicamente , Fallo Hepático/prevención & control , Masculino , Ratones , Ratones Endogámicos BALB C , Proteínas Proto-Oncogénicas c-bcl-2/genética , ARN Mensajero/metabolismo , Receptores del Factor de Necrosis Tumoral/genética , Receptores Tipo I de Factores de Necrosis Tumoral , Factor de Necrosis Tumoral alfa/metabolismo , Proteína bcl-X
12.
Cancer Res ; 61(12): 4779-83, 2001 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-11406552

RESUMEN

Cyclin D1, one of the G(1) cyclins, is frequently overexpressed in several types of carcinomas and is thought to play an important role in tumorigenesis and tumor progression including hepatocellular carcinoma. We constructed a retrovirus vector-carrying rat cyclin D1 cDNA in the reverse orientation, resulting in expression of antisense (AS) cyclin D1 mRNA. For efficient transduction of this recombinant retrovirus, two-step gene transfer was performed. The rat hepatoma cell line (dRLh84) was infected with this recombinant retrovirus after preinfection with adenovirus expressing the retrovirus receptor. In the rat hepatoma cells, AS cyclin D1 mRNA was expressed, inducing a decrease in the expression of endogenous cyclin D1 mRNA and an inhibition of cell growth. Moreover, two-step gene transfer of AS cyclin D1 into s.c. hepatoma xenografts resulted in inhibition of tumor growth and prolonged animal survival. In the virus-infected tumor xenografts, expression of cyclin D1 was immunohistochemically inhibited, and apoptosis of hepatoma cells was detected. These findings suggest that transduction of AS cyclin D1 is useful as an adjunct to standard treatments for hepatocellular carcinoma.


Asunto(s)
Ciclina D1/genética , ADN sin Sentido/genética , Terapia Genética , Neoplasias Hepáticas Experimentales/genética , Animales , Northern Blotting , División Celular/fisiología , Ciclina D1/biosíntesis , ADN sin Sentido/administración & dosificación , Técnicas de Transferencia de Gen , Humanos , Inmunohistoquímica , Neoplasias Hepáticas Experimentales/patología , Neoplasias Hepáticas Experimentales/terapia , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , ARN Mensajero/genética , Ratas , Ratas Wistar , Retroviridae/genética , Transducción Genética , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Cancer Res ; 61(7): 3016-21, 2001 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-11306481

RESUMEN

We previously reported that the retroviral vector expressing the herpes simplex virus-thymidine kinase gene under the control of 0.3-kb human alpha-fetoprotein (AFP) gene promoter (AF0.3) provided the cytotoxicity to ganciclovir (GCV) in high-AFP-producing human hepatoma cells but not in low-AFP-producing cells. Therefore, specific enhancement of AFP promoter activity is likely to be required to induce enough cytotoxicity in low-AFP-producing hepatoma cells. In this study, we constructed a hybrid promoter, [HRE]AF, in which a 0.4-kb fragment of human vascular endothelial growth factor 5'-flanking sequences containing hypoxia-responsive element (HRE) was fused to AF0.3 promoter. By means of the reporter gene transfection assay, hypoxia-inducible transcriptions that were mediated by [HRE]AF promoter were detected in low- and non-AFP-producing human hepatoma cells, but not in nonhepatoma cells. When the herpes simplex virus-thymidine kinase gene controlled by [HRE]AF promoter was transduced into hepatoma and nonhepatoma cells by a retroviral vector, the exposure to 1% O2 induced GCV cytotoxicity specifically in the hepatoma cells. Moreover, in nude mice bearing solid tumor xenografts, only the tumors consisting of the virus-infected hepatoma cells gradually disappeared by GCV administration. These results indicate that the hypoxia-inducible enhancer of the human vascular endothelial growth factor gene, which is directly linked to human AFP promoter, involves selective and enhanced tumoricidal activity in gene therapy for hepatocellular carcinoma.


Asunto(s)
Carcinoma Hepatocelular/terapia , Elementos de Facilitación Genéticos , Regulación Neoplásica de la Expresión Génica , Terapia Genética , Neoplasias Hepáticas/terapia , Regiones Promotoras Genéticas , alfa-Fetoproteínas/genética , Animales , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/inmunología , Hipoxia de la Célula/genética , Factores de Crecimiento Endotelial/genética , Ganciclovir/toxicidad , Vectores Genéticos/genética , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/inmunología , Linfocinas/genética , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Retroviridae/genética , Simplexvirus/enzimología , Simplexvirus/genética , Timidina Quinasa/genética , Timidina Quinasa/metabolismo , Activación Transcripcional , Transducción Genética , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular , alfa-Fetoproteínas/biosíntesis
14.
Chem Pharm Bull (Tokyo) ; 49(3): 249-52, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11253912

RESUMEN

Three NMR structures of alpha-conotoxin MI, a potent antagonist of the nicotinic acetylcholine receptor, have been refined using molecular dynamics (MD) simulation with explicit water. Although the convergence of the NMR structures of alpha-conotoxin MI was not sufficient to provide detailed structural features, the average structures obtained from MD simulations converged to one conformation, providing structural characteristics. The resulting structure was also found to be consistent with the results of amide proton-exchange experiments. These results demonstrate that MD simulation with explicit solvent water is very useful in refining NMR structures.


Asunto(s)
Conotoxinas/química , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Conformación Molecular , Solventes , Agua
16.
Biopolymers ; 58(4): 410-21, 2001 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-11180054

RESUMEN

Trifluoperazine (TFP) has been widely studied in relation to its mode of binding and its inactivation of calmodulin (CaM). Most studies in solution have indicated that CaM has two high-affinity binding sites for TFP. The crystal structure of the 1:4 CaM-TFP complex (CaM-4TFP) shows that three TFP molecules bind to the C-domain of CaM, and that one TFP molecule binds to the N-domain. In contrast, the crystal structure of the 1:1 CaM-TFP complex (CaM-1TFP) shows that one TFP molecule binds to the C-domain. It has been thought that the binding of one TFP molecule to the C-domain is followed by binding to the N-domain. The crystal structure of the 1:2 CaM-TFP complex (CaM-2TFP), moreover, has recently been determined, showing that two TFP molecules bind to the C-domain. In order to determine the structure of the CaM-TFP complex and to clarify the interaction between CaM and TFP in solution, we performed a molecular dynamics simulation of the CaM-TFP complex in aqueous solution starting from the CaM-4TFP crystal structure. The obtained solution structure is very similar to the CaM-2TFP crystal structure. The computer simulation showed that the binding ability of the secondary binding site of the C-domain is higher than that of the primary binding site of the N-domain.


Asunto(s)
Calmodulina/química , Trifluoperazina/química , Sitios de Unión , Simulación por Computador , Cristalografía por Rayos X , Bases de Datos Factuales , Modelos Moleculares , Conformación Proteica , Agua/química
17.
Biochem Biophys Res Commun ; 280(1): 368-73, 2001 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-11162525

RESUMEN

Several growth factors play an important role in liver regeneration. Once hepatic injury occurs, liver regeneration is stimulated by hepatocyte growth factor (HGF), transforming growth factor (TGF)-alpha, and heparin-binding epidermal growth factor-like growth factor (HB-EGF), whereas TGF-beta1 terminates liver regeneration. In this study, we analyzed the effect of a combination of HGF and epidermal growth factor (EGF) on mitogen-activated protein kinase (MAPK) activity and G1 cyclin expression in primary cultured rat hepatocytes. Treatment with a combination of HGF and EGF, in comparison with that of either HGF or EGF, induced tyrosine phosphorylation of both c-Met and EGF receptor (EGFR) independently and additively stimulated MAPK activity and cyclin D1 expression, resulting in additive stimulation of DNA synthesis. On the other hand, although TGF-beta1 treatment did not affect tyrosine phosphorylation of c-Met and EGFR, MAPK activity, and cyclin D1 expression, which were stimulated by HGF and EGF, DNA synthesis was completely inhibited through a marked decrease in cyclin E expression. These results indicate that potent mitogens, such as HGF, TGF-alpha, and HB-EGF, could induce the additive enhancement of liver regeneration cooperatively through an increase in Ras/MAPK activity followed by cyclin D1 expression, and that TGF-beta1 suppresses the growth factor-induced signals between cyclin D1 and cyclin E, resulting in the inhibition of DNA synthesis.


Asunto(s)
Ciclina D1/fisiología , ADN/biosíntesis , Sustancias de Crecimiento/farmacología , Hepatocitos/fisiología , Sistema de Señalización de MAP Quinasas/fisiología , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Animales , Células Cultivadas , Ciclina D1/biosíntesis , Factor de Crecimiento Epidérmico/farmacología , Fase G1 , Factor de Crecimiento de Hepatocito/farmacología , Hepatocitos/citología , Hepatocitos/efectos de los fármacos , Cinética , Hígado/citología , Masculino , Ratas , Ratas Wistar , Factor de Crecimiento Transformador beta/farmacología
18.
Ann Nucl Med ; 14(5): 361-7, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11108165

RESUMEN

To elucidate the change in perfusion and aerobic metabolism in myocarditis, tissue counting and dual tracer ex vivo autoradiography with Tl-201 and a free fatty acid analog, I-123- or I-125-labeled (p-iodophenyl)-methyl-pentadecanoic acid (BMIPP), were performed in rats with myocarditis induced by immunization with cardiac myosin. Inflammatory damage was classified histologically. At the acute stage (2-4 weeks after the antigen-injection), total heart uptakes of Tl and BMIPP and the ratio (BMIPP/Tl) were significantly reduced in myocarditis rats (N = 15) compared with the controls (N = 12). Myocardial distribution of Tl and BMIPP was not homogeneous. Relative uptake of Tl and BMIPP (N = 9, 128 regions) was gradually decreased with the extent of inflammation, and the regional BMIPP/Tl was smaller than the control. At the subacute stage (7 weeks after the antigen-injection), total Tl uptake in myocarditis rats (N = 5) recovered to the control level (N = 4), but that of BMIPP was still significantly lower than the control. BMIPP/Tl was still significantly lower in myocarditis. Myocardial distribution of Tl and BMIPP recovered to be more homogeneous. Relative uptake of Tl and BMIPP (N = 6, 78 regions) still gradually but significantly decreased with the extent of inflammation. Regional BMIPP/Tl was still depressed in myocarditis. These results indicate that myocardial perfusion and aerobic metabolism were discrepant and heterogeneously suppressed with severe inflammation during the acute stages, but the difference decreases with time. Examination with Tl-201 and BMIPP may provide information about the severity of myocarditis.


Asunto(s)
Enfermedades Autoinmunes/metabolismo , Ácidos Grasos/metabolismo , Ácidos Grasos/farmacocinética , Radioisótopos de Yodo/farmacocinética , Yodobencenos/farmacocinética , Miocarditis/metabolismo , Miocardio/metabolismo , Radiofármacos/farmacocinética , Animales , Enfermedades Autoinmunes/patología , Autorradiografía , Circulación Coronaria , Inflamación , Miocarditis/inmunología , Miocarditis/patología , Miocardio/patología , Miosinas/inmunología , Ratas , Radioisótopos de Talio/farmacocinética , Distribución Tisular
19.
Jpn Circ J ; 64(10): 755-9, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11059615

RESUMEN

Cardiac involvement is the major determinant of morbidity and mortality in patients with sarcoidosis, but clinical evaluation of the disease activity is occasionally difficult in cardiac sarcoidosis. The present study examined whether serum levels of interleukin-10 (IL-10) could reflect the disease activity of patients with cardiac sarcoidosis. Serum IL-10 levels were measured using an enzyme-linked immunosorbent assay, and compared with clinical manifestation, levels of angiotensin-converting enzyme (ACE), levels of lysozyme and accumulation of gallium-67 citrate. Sera were collected from 8 patients with cardiac sarcoidosis (CS group), 22 patients with miscellaneous heart diseases except for sarcoidosis (MHD group), and 8 healthy control subjects (HC group). Serum IL-10 levels of the CS group were significantly higher than those of the 2 control groups. Before steroid therapy, the levels of IL-10 in the CS group showed a significantly positive correlation with levels of ACE (r=0.868, p<0.05) and lysozyme (r=0.890, p<0.05). In 5 patients who were analyzed before and after steroid therapy, the levels of IL-10 tended to correlate with a decrease of an abnormal accumulation in gallium-67 citrate. Serum IL-10 levels may play a role in evaluation of the disease activity in patients with cardiac sarcoidosis.


Asunto(s)
Cardiomiopatías/fisiopatología , Interleucina-10/sangre , Sarcoidosis/fisiopatología , Adulto , Anciano , Cardiomiopatías/sangre , Cardiomiopatías/mortalidad , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad , Muramidasa/sangre , Renina/sangre , Sarcoidosis/sangre , Sarcoidosis/mortalidad
20.
Chem Pharm Bull (Tokyo) ; 48(11): 1835-7, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11086932

RESUMEN

Motilide, an erythromycin derivative, has been shown to equal activity to that of motilin as an agonist at the motilin receptor. However, there is little information on the three-dimensional (3D) structure-activity relationship between these two molecules, largely because they have quite different structures. In this study, we applied a rational computational procedure consisting of conformational analysis and a novel superposing method to investigate the 3D structure-activity relationship between motilide and motilin. We propose common 3D structural features between these molecules, which may be important for their similar activity.


Asunto(s)
Eritromicina/análogos & derivados , Motilina/análogos & derivados , Motilina/química , Eritromicina/química , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Conformación Molecular , Relación Estructura-Actividad
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