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1.
J Chem Phys ; 157(17): 174507, 2022 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-36347680

RESUMEN

The degradation of microplastics in relation to marine pollution has been receiving increasing attention. Because the spherulites that comprise microplastics have a highly ordered lamellar structure, their decomposition is thought to involve a lamellar structure collapse process. However, even in the simplest case of an order-disorder transition between lamellae and melt upon heating, the microscopic details of the transition have yet to be elucidated. In particular, it is unclear whether nucleation occurs at defects in the crystalline portion or at the interface between the crystalline and amorphous portions. To observe the transition in molecular simulations, an approach that distinguishes between the crystalline and amorphous structures that make up the lamella is needed. Local order parameters (LOPs) are an attempt to define the degree of order on a particle-by-particle basis and have demonstrated the ability to precisely render complex order structure transitions during phase transitions. In this study, 274 LOPs were considered to classify the crystalline and amorphous structures of polymers. Supervised machine learning was used to automatically and systematically search for the parameters. The identified optimal LOP does not require macroscopic information such as the overall orientation direction of the lamella layers but can precisely distinguish the crystalline and amorphous portions of the lamella layers using only a small amount of neighboring particle information.

2.
Tech Coloproctol ; 25(10): 1155-1161, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34095976

RESUMEN

BACKGROUND: Complete mesocolic excision (CME) with central vascular ligation (CVL) requires the surgeon to sharply dissect the mesocolon and approach the superior mesenteric artery (SMA) and superior mesenteric vein (SMV) for ligation of the supplying vessels relating to right-sided colon cancer at their origin. Even with preoperative images, it can still be challenging to identify these structures during laparoscopic surgery because of various intraoperative conditions. The aim of this study was to assess the efficacy of intraoperative ultrasound (IOUS) for identification of blood vessels during right-sided colon cancer surgery. METHODS: We performed IOUS on 19 patients diagnosed with right-sided colon cancer at our institution, in January-October 2020. Preoperatively, a three-dimensional computed tomography (3D-CT) angiogram was obtained for the majority of patients to visualize the SMA, SMV, and their respective branches. The running position of the ileocolic artery (ICA) and right colic artery (RCA) related to the SMV and the presence of the middle colic artery were identified and compared using preoperative 3D-CT, IOUS, and intraoperative findings. RESULTS: Nineteen patients [seven men and 12 women with a mean age of 73.9 ± 8.4 years (range 58-82 years)] were studied, including some with a body mass index of > 30 kg/m2, locally advanced cancer, and severe adhesion. There were IOUSs that detected the SMA, SMV, and their tributaries in all patients. The positional relationships between the SMV and the ICA and RCA revealed by IOUS were consistent with the preoperative and intraoperative findings. CONCLUSION: IOUS is a safe, feasible, and reproducible technique that can assist in detecting the branching of the SMA and SMV during CME with CVL in laparoscopic right-sided colon cancer surgery, regardless of individual conditions.


Asunto(s)
Neoplasias del Colon , Laparoscopía , Mesocolon , Anciano , Anciano de 80 o más Años , Colectomía , Neoplasias del Colon/diagnóstico por imagen , Neoplasias del Colon/cirugía , Femenino , Humanos , Ligadura , Masculino , Mesocolon/diagnóstico por imagen , Mesocolon/cirugía , Persona de Mediana Edad
3.
Am J Transplant ; 13(8): 1976-88, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23841873

RESUMEN

A strategy for inhibiting CD40 has been considered as an alternative approach for immunosuppression because of undesirable effects of anti-CD154 monoclonal antibodies (mAbs). Previously, we demonstrated that ASKP1240, which is a fully human anti-CD40 mAb, significantly prolonged kidney and liver allograft survival in cynomolgus monkeys without causing thromboembolic complications. Herein, we evaluated the effect of ASKP1240 on pancreatic islet transplantation (PITx) in cynomolgus monkeys. Diabetes was induced by total pancreatectomy, and islet allografts were transplanted into the liver. Following PITx (8201-12 438 IEQ/kg), blood glucose levels normalized promptly in all animals. Control islet allografts were rejected within 9 days (n = 3), whereas ASKP1240 (10 mg/kg) given on postoperative days 0, 4, 7, 11 and 14 (induction treatment, n = 5) significantly prolonged graft survival time (GST) to >15, >23, 210, 250 and >608 days, respectively. When ASKP1240 (5 mg/kg) was administered weekly thereafter up to post-PITx 6 months (maintenance treatment, n = 4), GST was markedly prolonged to >96, >115, 523 and >607 days. During the ASKP1240 treatment period, both anti-donor cellular responses and development of anti-donor antibodies were abolished, and no serious adverse events were noted. ASKP1240 appears to be a promising candidate for immunosuppression in clinical PITx.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Ligando de CD40/inmunología , Diabetes Mellitus Tipo 1/terapia , Supervivencia de Injerto , Trasplante de Islotes Pancreáticos , Islotes Pancreáticos/inmunología , Animales , Anticuerpos Monoclonales/farmacocinética , Ligando de CD40/antagonistas & inhibidores , Ligando de CD40/metabolismo , Diabetes Mellitus Tipo 1/etiología , Diabetes Mellitus Tipo 1/metabolismo , Humanos , Tolerancia Inmunológica , Islotes Pancreáticos/metabolismo , Macaca fascicularis , Masculino , Pancreatectomía/efectos adversos , Distribución Tisular , Trasplante Homólogo
4.
Clin Exp Immunol ; 173(2): 276-87, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23607598

RESUMEN

Acute respiratory distress syndrome (ARDS) is accompanied by severe lung inflammation induced by various diseases. Despite the severity of the symptoms, therapeutic strategies have been ineffective. High mobility group box 1 (HMGB1), which was identified originally as a DNA binding protein, has been proposed as a mediator of acute lung injury. In addition to its anti-coagulant activity, recombinant thrombomodulin (rTM) possesses an ability to suppress the inflammatory response through neutralizing HMGB1. T regulatory (T(reg)) cells in the lungs are reported to modify innate immune responses during resolution of acute lung injury. In the present study, we investigated the therapeutic effect of rTM, and the contribution of T(reg) cells to this effect, in a mouse model of severe ARDS. C57BL/6 mice received sequential intratracheal administration of α-galactosylceramide (α-GalCer) and lipopolysaccharide (LPS), which resulted in the development of severe ARDS. HMGB1 levels in the lungs increased to a higher level in ARDS mice compared to those in mice treated with LPS alone. HMGB1 was expressed in the infiltrating neutrophils and macrophages in lungs. T(reg) cells were reduced significantly in the lungs of ARDS mice compared to those in mice treated with LPS alone. rTM administration prolonged the survival time and ameliorated the development of ARDS, which was associated with increased T(reg) cells and synthesis of interleukin (IL)-10 and transforming growth factor (TGF)-ß in the lungs. These results suggest that HMGB1 is involved in the development of severe ARDS and rTM shows therapeutic effects through promoting the accumulation of T(reg) cells at the inflammatory sites.


Asunto(s)
Proteína HMGB1/metabolismo , Pulmón/metabolismo , Proteínas Recombinantes/administración & dosificación , Síndrome de Dificultad Respiratoria/metabolismo , Linfocitos T Reguladores/inmunología , Trombomodulina/administración & dosificación , Animales , Antígenos CD4/metabolismo , Modelos Animales de Enfermedad , Factores de Transcripción Forkhead/metabolismo , Regulación de la Expresión Génica/inmunología , Proteína HMGB1/genética , Humanos , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Pulmón/efectos de los fármacos , Pulmón/patología , Ratones , Ratones Endogámicos C57BL , Síndrome de Dificultad Respiratoria/tratamiento farmacológico , Síndrome de Dificultad Respiratoria/genética , Linfocitos T Reguladores/efectos de los fármacos
5.
Am J Transplant ; 9(8): 1732-41, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19519810

RESUMEN

Blockade of CD40-CD154 signaling pathway is an attractive strategy to induce potent immunosuppression and tolerance in organ transplantation. Due to its strong immunosuppressive effect shown in nonhuman primate experiments, anti-CD154 monoclonal antibodies (mAbs) have been tried in clinical settings, but it was interrupted by unexpected thromboembolic complications. Thus, inhibition of the counter molecule, CD40, has remained an alternative approach. In the previous preliminary study, we have shown that 4D11, a novel fully human anti-CD40 mAb, has a fairly potent immunosuppressive effect on kidney allograft in nonhuman primates. In this study, we aimed to confirm the efficacy and untoward events of the 2-week induction and 180-day maintenance 4D11 treatments. In both, 4D11 significantly suppressed T-cell-mediated alloimmune responses and prolonged allograft survival. Addition of weekly 4D11 administration after the induction treatment further enhanced graft survival. Complete inhibition of both donor-specific Ab and anti-4D11 Ab productions was obtained only with higher-dose maintenance therapy. No serious side effect including thromboembolic complications was noted except for a transient reduction of hematocrit in one animal, and decrease of peripheral B-cell counts in all. These results indicate that the 4D11 appears to be a promising candidate for immunosuppression in clinical organ transplantation.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Antígenos CD40/inmunología , Rechazo de Injerto/prevención & control , Trasplante de Riñón/inmunología , Animales , Anticuerpos Monoclonales/sangre , Anticuerpos Monoclonales/inmunología , Antígenos CD40/antagonistas & inhibidores , Ligando de CD40/antagonistas & inhibidores , Ligando de CD40/inmunología , Rechazo de Injerto/inmunología , Humanos , Terapia de Inmunosupresión , Inmunosupresores/uso terapéutico , Macaca fascicularis , Masculino , Modelos Animales , Transducción de Señal/inmunología
6.
Biomater Sci ; 6(5): 1002-1006, 2018 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-29569678

RESUMEN

Temperature-responsive cell culture substrates reported here can be dynamically programmed to induce bulk softening and surface roughness changes in the presence of living cells. Alterations in hepatocellular function following temporally controlled substrate softening depend on the extent of stiff mechanical priming prior to user-induced material transition.


Asunto(s)
Elasticidad , Elastómeros/química , Albúminas/metabolismo , Adhesión Celular/efectos de los fármacos , Elastómeros/farmacología , Exocitosis/efectos de los fármacos , Células Hep G2 , Humanos , Poliésteres/química , Resistencia a la Tracción
7.
J Hosp Infect ; 100(2): 211-213, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29452243

RESUMEN

Removal of bacteria by handwashing with ozonated water was evaluated using the ASTM E1174 standard test method. Thirty healthy volunteers were assigned randomly to three groups: ozonated water, antimicrobial soap and water, and non-antimicrobial soap and water. A 3 log10 cfu reduction was achieved by washing hands with ozonated water or antimicrobial soap and water. However, ozonated water was not significantly superior to non-antimicrobial soap and water. Ozonated water may remove bacteria from the hands to at least a similar extent as that by non-antimicrobial soap and water in the absence of visible dirt or body fluid contamination.


Asunto(s)
Bacterias/efectos de los fármacos , Desinfectantes/farmacología , Desinfección de las Manos/métodos , Mano/microbiología , Ozono/farmacología , Agua/farmacología , Adolescente , Adulto , Anciano , Bacterias/crecimiento & desarrollo , Bacterias/aislamiento & purificación , Recuento de Colonia Microbiana , Femenino , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Adulto Joven
8.
J Clin Invest ; 67(1): 51-9, 1981 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-6256414

RESUMEN

To elucidate the metabolic abnormality of musclar dystrophy, 27 kinds of enzyme activity in various organs of control and dystrophic mice were examined. The organs examined included muscle, bone, heart, testis, uterus, spleen, thymus, submaxillary gland, stomach, pancreas, liver, kidney, brain, and lung. The activities of 14 different aminopeptidases, 5 endopeptidases, 4 glycosidases, phosphatase, esterase, and ribonuclease were measured. Most of the enzyme activities were significantly elevated in muscles and bones of dystrophic mice. These organs were similar in their patterns of enzyme abnormality. Among the 14 kinds of aminopeptidase activity studied, the degree of increased activity was greater for the aminopeptidases (AP):Ala-AP, Leu-AP, Met-AP, Phe-AP, Trp-AP, Gly-Pro-Leu-AP. In addition to aminopeptidases, there were significant increases in activities of chymotrypsinlike enzyme, cathepsin C, cathepsin D, several glycosidases and neutral ribonuclease in the muscles of dystrophic mice. Similarly increased enzyme activity was also observed in organs other than muscle and bone. Furthermore, protein content in most organs was higher in dystrophic mice than in those of control mice. These abnormalities were seen in both males and females. The present results suggest that there are extensive abnormalities in the protein metabolism in dystrophic mice. It seems therefore that the therapeutic approach to muscular dystrophy should be studies not only from the well-known abnormality of intramuscular endopeptidases, but from other aspects as well.


Asunto(s)
Hidrolasas/metabolismo , Músculos/enzimología , Distrofia Muscular Animal/enzimología , Péptido Hidrolasas/metabolismo , Animales , Huesos/enzimología , Esterasas/metabolismo , Glicósido Hidrolasas/metabolismo , Ratones , Ratones Endogámicos C57BL , Monoéster Fosfórico Hidrolasas/metabolismo , Ribonucleasas/metabolismo
9.
J Clin Invest ; 96(1): 69-77, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7615838

RESUMEN

To investigate how cardiac myocytes recover from a brief period of ischemia, we used a metabolic inhibition (MI) model, one of the in vitro ischemic models, of chick embryo ventricular myocytes, and examined the induction of immediate-early (IE) genes mRNAs and the activity of mitogen-activated protein (MAP) kinase. We performed Northern blot analysis to study the expression of c-jun, c-fos, and c-myc mRNAs during MI using 1 mM NaCN and 20 mM 2-deoxy-d-glucose, and also during the recovery from MI of 30 min. The c-fos mRNA was induced transiently at 30 and 60 min during the recovery. The expression of c-jun mRNA was significantly augmented at 30, 60, 90, and 120 min during the recovery (3.0-, 4.7-, 2.4-, and 1.9-fold induction, respectively) and so did the expression of c-myc mRNA (1.4-, 1.7-, 1.8-, and 2.0-fold induction, respectively). In contrast, the levels of these mRNAs remained unchanged during MI. The electrophoretic mobility shift assay revealed that AP-1 DNA binding activity markedly increased at 120 min during the recovery. When the cells were pretreated with protein kinase C (PKC) inhibitors, 100 microM H-7 or 1 microM staurosporine, the induction of c-jun mRNA at 60 min during the recovery was markedly suppressed (95 or 82% reduction, respectively). The c-jun induction was partially inhibited when the cells were treated with 2 mM EGTA during MI and the recovery (42% reduction). MAP kinase activity quantified with in-gel kinase assay was unchanged during MI, but significantly increased at 5, 10, and 15 min during the recovery (3.0-, 4.1-, and 3.4-fold increase, respectively). S6 kinase activity was also augmented significantly at 15 min during the recovery. Thus, these data suggest that IE genes as well as MAP kinase may play roles in the recovery process of cardiac myocytes from MI, and that the augmentation of c-jun expression needs the activation of PKC and to some extent, [Ca2+]i.


Asunto(s)
Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Regulación de la Expresión Génica , Genes Inmediatos-Precoces , Isquemia Miocárdica/metabolismo , Miocardio/metabolismo , Animales , Secuencia de Bases , Células Cultivadas , Embrión de Pollo , Proteínas Quinasas Dependientes de AMP Cíclico/fisiología , Activación Enzimática , Genes jun , Datos de Secuencia Molecular , Proteína Quinasa C/fisiología , ARN Mensajero/análisis , Activación Transcripcional
10.
J Clin Invest ; 92(4): 1957-66, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8408648

RESUMEN

The present study was performed to clarify the relationship between human T cell lymphotropic virus type I (HTLV-I) infection and chronic inflammatory arthropathy. To determine the ability of HTLV-I to infect synovial cells and the effect on synovial cell proliferation, synovial cells were cocultured with the HTLV-I-producing T cell lines (MT-2 or HCT-1). After coculture with HTLV-I-infected T cells, the synovial cells expressed HTLV-I-specific core antigens, and HTLV-I proviral DNA was detected from the synovial cells by polymerase chain reaction. These cocultured synovial cells with HTLV-I-infected T cells proliferated more actively than the synovial cells cocultured with uninfected T cells. This stimulatory effect of HTLV-I-infected T cells on synovial cell proliferation seems necessary to contact each other. After being cocultured with MT-2 cells, synovial cells proliferated more actively than control cells even after several passages. Furthermore, HTLV-I-infected synovial cells produced significant amounts of granulocyte/macrophage colony-stimulating factor. These results suggest that HTLV-I can infect synovial cells, resulting their active proliferation and may be involved in the pathogenesis of proliferative synovitis similar to that found in rheumatoid arthritis.


Asunto(s)
Factor Estimulante de Colonias de Granulocitos y Macrófagos/biosíntesis , Virus Linfotrópico T Tipo 1 Humano/fisiología , Membrana Sinovial/citología , Membrana Sinovial/metabolismo , Artritis Reumatoide/metabolismo , Artritis Reumatoide/patología , División Celular , Línea Celular , Células Cultivadas , Medios de Cultivo Condicionados , ADN Viral/análisis , Técnica del Anticuerpo Fluorescente , Productos del Gen gag/análisis , Productos del Gen gag/biosíntesis , Humanos , Técnicas para Inmunoenzimas , Inmunohistoquímica , Mitomicina/farmacología , Reacción en Cadena de la Polimerasa/métodos , Provirus/fisiología , Membrana Sinovial/efectos de los fármacos , Linfocitos T , Replicación Viral
11.
Mucosal Immunol ; 10(4): 1043-1055, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-27966554

RESUMEN

Influenza virus causes a respiratory disease in humans that can progress to lung injury with fatal outcome. The interleukin (IL)-36 cytokines are newly described IL-1 family cytokines that promote inflammatory responses via binding to the IL-36 receptor (IL-36R). The mechanism of expression and the role of IL-36 cytokines are poorly understood. Here, we investigated the role of IL-36 cytokines in modulating the innate inflammatory response during influenza virus-induced pneumonia in mice. The intranasal administration of influenza virus upregulated IL-36α mRNA and protein production in the lungs. In vitro, influenza virus-mediated IL-36α but not IL-36γ is induced and secreted from alveolar epithelial cells (AECs) through both a caspase-1 and caspase-3/7 dependent pathway. IL-36α was detected in microparticles shed from AECs and promoted the production of pro-inflammatory cytokines and chemokines in respiratory cells. IL-36R-deficient mice were protected from influenza virus-induced lung injury and mortality. Decreased mortality was associated with significantly reduced early accumulation of neutrophils and monocytes/macrophages, activation of lymphocytes, production of pro-inflammatory cytokines and chemokines, and permeability of the alveolar-epithelial barrier in despite impaired viral clearance. Taken together, these data indicate that IL-36 ligands exacerbate lung injury during influenza virus infection.


Asunto(s)
Células Epiteliales Alveolares/metabolismo , Subtipo H1N1 del Virus de la Influenza A/fisiología , Lesión Pulmonar/inmunología , Pulmón/patología , Neutrófilos/inmunología , Infecciones por Orthomyxoviridae/inmunología , Receptores de Interleucina-1/metabolismo , Células Epiteliales Alveolares/inmunología , Células Epiteliales Alveolares/virología , Animales , Micropartículas Derivadas de Células/metabolismo , Células Cultivadas , Citocinas/metabolismo , Humanos , Inmunidad Innata , Mediadores de Inflamación/metabolismo , Gripe Humana/inmunología , Interleucina-1/metabolismo , Pulmón/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores de Interleucina-1/genética , Carga Viral
12.
SAR QSAR Environ Res ; 28(6): 511-524, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28728491

RESUMEN

In Europe, REACH legislation encourages the use of alternative in silico methods such as (Q)SAR models. According to the recent progress of Chemical Substances Control Law (CSCL) in Japan, (Q)SAR predictions are also utilized as supporting evidence for the assessment of bioaccumulation potential of chemicals along with read across. Currently, the effective use of read across and QSARs is examined for other hazards, including biodegradability. This paper describes the results of external validation and improvement of CATALOGIC 301C model based on more than 1000 tested new chemical substances of the publication schedule under CSCL. CATALOGIC 301C model meets all REACH requirements to be used for biodegradability assessment. The model formalism built on scientific understanding for the microbial degradation of chemicals has a well-defined and transparent applicability domain. The model predictions are adequate for the evaluation of the ready degradability of chemicals.


Asunto(s)
Biodegradación Ambiental , Contaminantes Ambientales/química , Sustancias Peligrosas/química , Modelos Biológicos , Análisis de la Demanda Biológica de Oxígeno , Bases de Datos de Compuestos Químicos , Contaminantes Ambientales/metabolismo , Sustancias Peligrosas/metabolismo , Japón , Relación Estructura-Actividad Cuantitativa , Reproducibilidad de los Resultados
13.
Circ Res ; 89(7): 591-8, 2001 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-11577024

RESUMEN

Physiological and pathological cardiac hypertrophy have directionally opposite changes in transcription of thyroid hormone (TH)-responsive genes, including alpha- and beta-myosin heavy chain (MyHC) and sarcoplasmic reticulum Ca(2+)-ATPase (SERCA), and TH treatment can reverse molecular and functional abnormalities in pathological hypertrophy, such as pressure overload. These findings suggest relative hypothyroidism in pathological hypertrophy, but serum levels of TH are usually normal. We studied the regulation of TH receptors (TRs) beta1, alpha1, and alpha2 in pathological and physiological rat cardiac hypertrophy models with hypothyroid- and hyperthyroid-like changes in the TH target genes, alpha- and beta-MyHC and SERCA. All 3 TR subtypes in myocytes were downregulated in 2 hypertrophy models with a hypothyroid-like mRNA phenotype, phenylephrine in culture and pressure overload in vivo. Myocyte TRbeta1 was upregulated in models with a hyperthyroid-like phenotype, TH (triiodothyronine, T3), in culture and exercise in vivo. In myocyte culture, TR overexpression, or excess T3, reversed the effects of phenylephrine on TH-responsive mRNAs and promoters. In addition, TR cotransfection and treatment with the TRbeta1-selective agonist GC-1 suggested different functional coupling of the TR isoforms, TRbeta1 to transcription of beta-MyHC, SERCA, and TRbeta1, and TRalpha1 to alpha-MyHC transcription and increased myocyte size. We conclude that TR isoforms have distinct regulation and function in rat cardiac myocytes. Changes in myocyte TR levels can explain in part the characteristic molecular phenotypes in physiological and pathological cardiac hypertrophy.


Asunto(s)
Cardiomegalia/fisiopatología , Regulación de la Expresión Génica , Miocardio/metabolismo , Receptores de Hormona Tiroidea/genética , Receptores de Hormona Tiroidea/metabolismo , Animales , ATPasas Transportadoras de Calcio/genética , ATPasas Transportadoras de Calcio/metabolismo , Células Cultivadas , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/efectos de los fármacos , Masculino , Actividad Motora , Miocardio/citología , Cadenas Pesadas de Miosina/genética , Cadenas Pesadas de Miosina/metabolismo , Fenotipo , Fenilefrina/farmacología , Condicionamiento Físico Animal , Isoformas de Proteínas/agonistas , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Receptores de Hormona Tiroidea/agonistas , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico , Transfección , Triyodotironina/farmacología
14.
J Natl Cancer Inst ; 54(5): 1255-6, 1975 May.
Artículo en Inglés | MEDLINE | ID: mdl-165316

RESUMEN

The effect of six protease inhibitors, isolated from various species of actinomycetes, on focus formation by murine sarcoma virus was examined. Pepstatin was the only inhibitor. The treatment of cells with pepstatin at various times possibly retards the early stage of infection with murine sarcoma virus.


Asunto(s)
Transformación Celular Neoplásica , Gammaretrovirus/efectos de los fármacos , Inhibidores de Proteasas , Virus del Sarcoma Murino/efectos de los fármacos , Animales , Carbamatos/farmacología , División Celular/efectos de los fármacos , Inhibición de Contacto/efectos de los fármacos , Dipéptidos/farmacología , Leupeptinas/farmacología , Ratones , Ratones Endogámicos C57BL , Oligopéptidos/farmacología , Compuestos Organofosforados/farmacología , Elastasa Pancreática/farmacología , Pepstatinas/farmacología , Termolisina/antagonistas & inhibidores
15.
Cancer Res ; 38(10): 3505-8, 1978 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-210941

RESUMEN

Activities of various hydrolytic enzymes were determined in rat organ homogenates and on the surface of cells from various sources, i.e., tumor cell strains, primary cultured cells, normal cells, and their transformants. Alanine, leucine, methionine, phenylalanine, and glycyl-proline aminopeptidases and esterase showed relatively high activities in all these organs and cells. In the kidney homogenate the aminopeptidase A activity was higher in other organs; i.e., the aminopeptidase A activity was lower than that of aminopeptidase B. Normal cells derived from kidneys showed the kidney-type pattern of amino-peptidases A and B on the surface of cells, whereas tumor cells from various origins were of another organ type. When cultured mouse fibroblast strain C3H2K and rat fibroblast strain 3Y1 cells were transformed by SV40 or by a ts A mutant and maintained at permissive temperature, aminopeptidase A activity was drastically decreased, and the ratio of aminopeptidase A to aminopeptidase B was reduced to the levels of tumor cells. If the ts A mutant-transformed cells were grown at the restrictive temperature, the ratio approached that of normal cells. In normal cells, however, cultivation at high or low temperature did not cause any change of the activities.


Asunto(s)
Aminopeptidasas/metabolismo , Membrana Celular/enzimología , Transformación Celular Neoplásica , Neoplasias Experimentales/enzimología , Animales , Línea Celular , Perros , Femenino , Riñón/enzimología , Pulmón/enzimología , Ratones , Mutación , Ratas , Virus 40 de los Simios/genética , Temperatura
16.
J Hosp Infect ; 94(4): 341-345, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27760708

RESUMEN

BACKGROUND: Sixteen pertussis cases in haemodialysis patients and healthcare workers were detected in a 25-bed outpatient haemodialysis facility in Japan between October 2013 and April 2014. AIM: To describe an outbreak of pertussis among patients and healthcare workers, and to identify risk factors for pertussis infection. METHODS: Sputum cultures, loop-mediated isothermal amplification assays performed on nasopharyngeal swabs to detect respiratory pathogens including Bordetella pertussis, and serum anti-pertussis toxin immunoglobulin G measurements were performed for all haemodialysis patients and healthcare workers. A retrospective case-control study was performed to identify the risk factors for pertussis infection in the clinic. FINDINGS: Only six of the 16 pertussis patients (37.5%) had respiratory symptoms. Recent exposure to an unmasked individual with a cough was associated with pertussis infection (odds ratio 6.25, P<0.05). The outbreak was terminated successfully after enforcing the use of surgical masks among both patients and healthcare workers. CONCLUSION: This report demonstrates the risk of pertussis transmission in a haemodialysis facility, and underscores the importance of wearing surgical masks to control a pertussis outbreak.


Asunto(s)
Infección Hospitalaria/epidemiología , Brotes de Enfermedades , Personal de Salud , Pacientes , Tos Ferina/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Bordetella pertussis/genética , Bordetella pertussis/aislamiento & purificación , Estudios de Casos y Controles , Infección Hospitalaria/transmisión , Diálisis , Transmisión de Enfermedad Infecciosa , Femenino , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Técnicas de Diagnóstico Molecular , Nasofaringe/microbiología , Estudios Retrospectivos , Factores de Riesgo , Esputo/microbiología , Tos Ferina/transmisión
17.
Biochim Biophys Acta ; 616(1): 60-7, 1980 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-7437450

RESUMEN

A specific enzyme for the liberation of N-terminal N-formylmethionine from N-formylmethionyl peptides was purified 4750-fold from rat liver by successive applications of (NH4)SO4 precipitation, DEAE-cellulose, N-formylbestatin-AH-Sepharose 4B and AH-Sepharose 4B chromatography followed by Sepharose CL-6B gel filtration. The molecular weight was determined by gel filtration on Sepharose CL-6B as 290 000 +/- 5000. This was suggested to be a tetramer consisting of a subunit which was shown by sodium dodecyl sulphate (SDS)-polyacrylamide gel electrophoresis to have a 72 000 +/- 2000 molecular weight. The optimum pH of the enzyme was 7.8. Cd2+ and Hg2+ were highly toxic to the enzyme. Michaelis constants of N-formylmethionyl leucine and N-formylmethionine beta-naphthylamide were 0.03 and 0.2 mM, respectively.


Asunto(s)
Aminopeptidasas/aislamiento & purificación , Hígado/enzimología , Animales , Cromatografía de Afinidad , Cinética , Masculino , Peso Molecular , Ratas
18.
Biochim Biophys Acta ; 613(2): 459-68, 1980 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-7448199

RESUMEN

1. Amastatin, a specific inhibitor of aminopeptidase A (L-alpha-aspartyl(L-alpha-glutamyl)-peptide hydrolase, EC 3.4.11.7), was linked to an agarose matrix and by this affinity chromatography aminopeptidase A of pig kidneys was purified as a single protein shown by acrylamide gel electrophoresis. 2. Aminopeptidase A which was purified 710-fold, hydrolyzed only acidic amino acid beta-naphthylamide. The optimum pH and the optimum temperature was 7.5 and 45-50 degrees C, respectively. 3. The molecular weight was approx. 300 000 as determined by Sephadex G-200 gel filtration. 4. The activity of aminopeptidase A was not affected by sulfhydryl agents, S-S dissociating agents and serine proteinase inhibitor, but was inhibited strongly by metal chelating agents, and enhanced by alkaline earth metals. 5. Amastatin inhibited aminopeptidase A in a competitive manner with L-glutamic acid beta-naphthylamide, and the Ki value was calculated to be 2.5 x 10(-7) M. The inhibitory effect of amastatin on aminopeptidase A was not reversed by addition of Ca2+.


Asunto(s)
Aminopeptidasas/aislamiento & purificación , Antibacterianos , Riñón/enzimología , Péptidos , Aminopeptidasas/antagonistas & inhibidores , Animales , Cromatografía de Afinidad , Glutamil Aminopeptidasa , Humanos , Oligopéptidos , Porcinos
19.
Biochim Biophys Acta ; 452(1): 131-43, 1976 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-990309

RESUMEN

Activities of hydrolytic enzymes on the surface of monkey kidney, canine kidney, L. FM3A and various tumor cells were determined and compared with those in the cell homogenate. Although aminopeptidase (EC 3.4.11.-) activities were always detected on the surface membrane in mammalian cells, trypsin, chymotrypsin and elastase activities were not detected while slight glycosidase activity was detected in a suspension of cultured cells. The activities of alanine-, leucine-, methionine- and phenylalanine-aminopeptidases were rather high but aminopeptidase A, proline-, valine-, glycyl propline dipeptidyl-and glycyl propyl leucine-tripeptidyl-aminopeptidases showed relatively low activities. Aminopeptidase activity was also demonstrated in the isolated membrane fractions. The specific activities of enzymes in these membrane fractions were not significantly greater than in cell homogenate so it was concluded that these enzyme activities were rather loosely bound to the cell membrane. Further evidence for the localization of the aminopeptidase activities on the cell surface was obtained by using glass-bead-bound substrate and detecting the release of the terminal residues. When bestatin, a specific inhibitor against aminopeptidase B and leucine aminopeptidase, was included in the assay system for the enzyme activities on the cell surface, the enzymes were commonly inhibited in all types of cells.


Asunto(s)
Aminopeptidasas/metabolismo , Membrana Celular/enzimología , Tampones (Química) , Línea Celular , Glicósido Hidrolasas/metabolismo , Cinética , Leucil Aminopeptidasa/metabolismo
20.
Biochim Biophys Acta ; 1200(1): 11-8, 1994 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-8186227

RESUMEN

We examined the effect of 1-benzylimidazole on the induction of cytochrome P-450 1A1/2 (P-450 1A1/2) and cytochrome P-450 2B1/2 (P-450 2B1/2) in normal, castrated, ovariectomized and hypophysectomized male rats, and in castrated rats treated with testosterone. 1-Benzylimidazole markedly increased P-450 content in male and female rats. Parallel to the dose-dependent increase in P-450 content, 1-benzylimidazole produced a significant increase in P-450 2B1/2 in male rats, but not in female rats. 1-Benzylimidazole failed to induce P-450 2B1/2 in castrated male and ovariectomized female rats. Treatment of castrated male rats with testosterone restored the induction of P-450 2B1/2 by 1-benzylimidazole. Treatment of ovariectomized female rats with 1-benzylimidazole or phenobarbital led to the increase in P-450 content, accompanying by the induction of P-450 2B1/2 by the latter treatment, but not the former. In hypophysectomized male rats, 1-benzylimidazole was able to induce P-450 2B1/2 in contrast to castrated male rats. Neonatal male and female rats responded well to the induction of P-450 2B1/2 by 1-benzylimidazole. The present findings suggest that P-450 2B1/2 induction by 1-benzylimidazole would be coupled with circulating testosterone regulated by hypophysis-testis axis. 1-Benzylimidazole produced sex-differentiated induction of P-450 2B1/2 in pubertal rats, but not in neonatal animals. The present findings would be provide information on a unique effect of 1-benzylimidazole on P-450 2B1/2 induction in rats.


Asunto(s)
Hidrocarburo de Aril Hidroxilasas , Sistema Enzimático del Citocromo P-450/biosíntesis , Imidazoles/farmacología , Microsomas Hepáticos/efectos de los fármacos , Esteroide Hidroxilasas/biosíntesis , Testosterona/farmacología , Animales , Animales Recién Nacidos , Castración , Relación Dosis-Respuesta a Droga , Inducción Enzimática/efectos de los fármacos , Femenino , Hipofisectomía , Masculino , Microsomas Hepáticos/enzimología , Ratas , Ratas Wistar , Factores Sexuales
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