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1.
Amino Acids ; 43(3): 1331-7, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22203366

RESUMEN

γ-Aminobutyric acid (GABA) is a kind of amino acid contained in green tea leaves and other foods. Several reports have shown that GABA might affect brain protein synthesis, improve many brain functions such as memory and study capability, lower the blood pressure of spontaneously hypertensive rats, and may also have a relaxation effect in humans. However, the evidence for its mood-improving function is still not sufficient. In this study, we investigated how the oral intake of GABA influences human adults psychologically and physiologically under a condition of mental stress. Sixty-three adults (28 males, 35 females) participated in a randomized, single blind, placebo-controlled, crossover-designed study over two experiment days. Capsules containing 100 mg of GABA or dextrin as a placebo were used as test samples. The results showed that EEG activities including alpha band and beta band brain waves decreased depending on the mental stress task loads, and the condition of 30 min after GABA intake diminished this decrease compared with the placebo condition. That is to say, GABA might have alleviated the stress induced by the mental tasks. This effect also corresponded with the results of the POMS scores.


Asunto(s)
Afecto/efectos de los fármacos , Solución de Problemas/efectos de los fármacos , Estrés Psicológico/tratamiento farmacológico , Tranquilizantes/administración & dosificación , Ácido gamma-Aminobutírico/administración & dosificación , Administración Oral , Adulto , Ritmo alfa/efectos de los fármacos , Ritmo beta/efectos de los fármacos , Encéfalo/efectos de los fármacos , Estudios Cruzados , Ecoencefalografía , Femenino , Humanos , Masculino , Método Simple Ciego , Estadísticas no Paramétricas , Estrés Psicológico/diagnóstico por imagen , Resultado del Tratamiento , Adulto Joven
2.
Phys Rev Lett ; 104(24): 247201, 2010 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-20867330

RESUMEN

Electronic structures of the quantum critical superconductor ß-YbAlB4 and its polymorph α-YbAlB4 are investigated by using bulk-sensitive hard x-ray photoemission spectroscopy. From the Yb 3d core level spectra, the values of the Yb valence are estimated to be ∼2.73 and ∼2.75 for α- and ß-YbAlB4, respectively, thus providing clear evidence for valence fluctuations. The valence band spectra of these compounds also show Yb2+ peaks at the Fermi level. These observations establish an unambiguous case of a strong mixed valence at quantum criticality for the first time among heavy fermion systems, calling for a novel scheme for a quantum critical model beyond the conventional Doniach picture in ß-YbAlB4.

3.
J Oral Pathol Med ; 37(4): 221-7, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18221325

RESUMEN

BACKGROUND: Intraosseous ameloblastoma (IA) is the quintessence of epithelial odontogenic tumor and histologically and behaviorally defined as an undoubted neoplastic process. Current information must lead to the consensus that IA arises from the embryologic inclusions of odontogenic epithelium within the jawbone. Nevertheless, clinically oriented evidence is limited to this day. METHODS: The clinical and radiographic features, behavior, and pathology of 14 cases of small IA confined to the alveolar region were systematically examined. RESULTS: Six cases were a chance finding. There was no gender predilection and half of the lesions clustered in middle age (>40 years). The posterior region of the mandible (n = 7) and the anterior segment of the maxilla (n = 4) were favored. Five radiographic characteristics were recognized: interradicular (n = 5) and periradicular (n = 3), and periapical, residual and pericoronal (n = 2 each). They showed solid (n = 12) or unicystic (n = 2) growth pattern and 12 lesions were divided into seven follicular, three desmoplastic, and two plexiform subtypes. The main location of tumor was microscopically traceable in six cases; three interradicular type outside the periodontal ligament space and two periradicular and one periapical variants inside. CONCLUSION: By in-depth evaluation of the spatial relationship between tumor and its surrounding structure, the alveolar process, periodontal ligament space, and pericoronal area are all the likely starting points of IA. This report re-awakens the oral pathologist to the histogenetic significance of incipient IA as the only available human specimen for reappraisal of their origin.


Asunto(s)
Proceso Alveolar/patología , Ameloblastoma/patología , Neoplasias Maxilomandibulares/patología , Adulto , Epitelio/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad
4.
J Oral Pathol Med ; 37(1): 43-9, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18154577

RESUMEN

BACKGROUND: Myopericytoma (MPC) is a generic denomination to describe tumors showing differentiation toward perivascular myoid cells /myopericytes. It has been suggested that MPC forms a morphologic continuum with glomus tumor (GT), solitary myofibroma (SMF), and angioleiomyoma (ALM). This proposed relationship has not yet been assessed in the oral region. METHODS: We reviewed our 28-year experience with 35 oral tumors, originally diagnosed as ALM (n = 28), SMF (n = 4), GT (n = 2), and MPC (n = 1) to analyze their overlapping microscopic features, with the assistance of immunohistochemistry. RESULTS: Myopericytoma showed a wide range of growth patterns; concentric perivascular whorls, hemangiopericytomatous areas, glomangiopericytoma (GPC)-type vessels and leiomyomatous foci. Intravascular growth was also seen. Among 28 cases studied, three ALM were reclassified as MPC (n = 2) and SMF (n = 1), based on the present diagnostic criteria. Additional MPC-type components, at varying degrees, were similarly found in four ALM and three SMF, at least focally. One GT featured intravascular whorls of spindle cells. These four interrelated groups of tumors had in common GPC-type vasculature and intraluminal cellular proliferation was nearly ubiquitously present. Diffuse immunoreactivity for alpha-smooth muscle actin and less staining intensity of muscle-specific actin were observed in all tumors. Only ALM displayed desmin positivity of variable extent. Neither case tested expressed CD34. CONCLUSIONS: Our data matches with the recent results in extraoral sites that MPC, GT, SMF, and ALM exhibit histologic and immunohistochemical overlap with each other. A common perivascular myoid differentiation between these tumor types is further reinforced by the present oral series.


Asunto(s)
Angiomioma/patología , Tumor Glómico/patología , Hemangiopericitoma/patología , Neoplasias Maxilomandibulares/patología , Neoplasias de la Boca/patología , Miofibroma/patología , Actinas/análisis , Adulto , Anciano , Angiomioma/química , Antígenos CD34/análisis , Desmina/análisis , Femenino , Tumor Glómico/química , Hemangiopericitoma/química , Humanos , Técnicas para Inmunoenzimas , Neoplasias Maxilomandibulares/química , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/química , Miofibroma/química , Neoplasias de Tejido Muscular/clasificación , Neoplasias de Tejido Vascular/clasificación
5.
Acta Neurochir (Wien) ; 150(8): 847-8, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18574549

RESUMEN

A 30 year old female with a fusiform aneurysm of the cervical vertebral artery causing nerve root compression and associated with neurofibromatosis-1 was successfully treated with endovascular methods which resolved the mass effect. This is the first report demonstrating the reduction of the mass effect of an aneurysm on a cervical nerve root with endovascular treatment by using MR neurography.


Asunto(s)
Vértebras Cervicales/irrigación sanguínea , Embolización Terapéutica , Neurofibromatosis 1/complicaciones , Arteria Vertebral , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética , Síndromes de Compresión Nerviosa/diagnóstico , Síndromes de Compresión Nerviosa/etiología , Síndromes de Compresión Nerviosa/terapia , Neurofibromatosis 1/diagnóstico , Examen Neurológico , Raíces Nerviosas Espinales/patología , Tomografía Computarizada por Rayos X , Arteria Vertebral/patología
6.
Neuroscience ; 146(2): 494-8, 2007 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-17368741

RESUMEN

We examined the circadian expression of mousePeriod (mPer) genes (mPer1 and mPer2) and the proliferation of the neural stem cells in vitro. The neural stem cells from the ganglionic eminence of embryonic mice were expanded by the neurosphere method and then treated with epidermal growth factor (EGF) to stimulate their mitotic activity. The time courses of the proliferation were examined by WST-8 assay and bromodeoxyuridine (BrdU) incorporation assay and the expression of mPer1 and mPer2 genes was examined by RT-PCR and immunocytochemistry. We have found that EGF treatment elicited the circadian change in both the increase in viable cell number and DNA synthesis activity of the neural stem cells. Also, the gene expression of mPer2, but not mPer1, changed rhythmically with a period of 24 h and correlated negatively with the DNA synthesis activity rhythm. Furthermore, the treatment with an antisense oligonucleotide against mPer2 increased the DNA synthesis activity of the neural stem cells. These results suggest that mPer2 might periodically suppress the proliferation of neural stem cells.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Proliferación Celular , Ritmo Circadiano/fisiología , Expresión Génica/fisiología , Neuronas/fisiología , Proteínas Nucleares/metabolismo , Células Madre/metabolismo , Factores de Transcripción/metabolismo , Animales , Bromodesoxiuridina/metabolismo , Proteínas de Ciclo Celular/genética , Proliferación Celular/efectos de los fármacos , Embrión de Mamíferos , Factor de Crecimiento Epidérmico/farmacología , Ratones , Ratones Endogámicos ICR , Neuronas/efectos de los fármacos , Proteínas Nucleares/genética , Proteínas Circadianas Period , ARN Mensajero/biosíntesis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Células Madre/efectos de los fármacos , Factores de Tiempo , Factores de Transcripción/genética
7.
AJNR Am J Neuroradiol ; 27(2): 264-9, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16484389

RESUMEN

BACKGROUND AND PURPOSE: Although dynamic contrast-enhanced MR angiography studies for arteriovenous malformations (AVFs) and brain tumors have shown promising results, no formal attempt has yet been made to similarly evaluate dural AVFs. To assess the practical applicability of 2D thick-section contrast enhanced MR digital subtraction angiography (MRDSA) for the diagnosis and management of dural AVFs, MRDSA and intra-arterial digital subtraction angiography (IADSA) were comparatively evaluated. METHODS: We performed 80 consecutive MRDSA studies for 25 dural AVFs, including 11 cavenous sinuses, 9 sigmoid sinuses, 2 tentorial sinuses, one anterior condylar vein, one craniocervical junction, and one spine. MR images were continuously obtained following the initiation of a bolus injection of gadrinium chelates and subtraction images were constructed. We thereafter evaluated the imaging quality and hemodynamic information from all 46 MRDSA images performed in parallel with IADSA in either perioperative or follow-up studies. RESULTS: Most MRDSA images detected early venous filling, sinus occlusion, leptomeningeal venous drainage, and varices. It was difficult, however, to identify the feeding arteries because of both the partial volume effect and a low spatial resolution. Most important, MRDSA accurately detected aggressive lesions with leptomeningeal venous drainage and varices. CONCLUSION: Our MRDSA technique was found to have limited value for depicting all the anatomic details of dural AVFs, though it was able to identify important hemodynamic abnormalities related to the risk of hemorrhaging. MRDSA is therefore useful as a less invasive, dynamic angiographic tool, not only for perioperative studies but also for follow-up studies.


Asunto(s)
Angiografía de Substracción Digital/métodos , Malformaciones Vasculares del Sistema Nervioso Central/diagnóstico , Procesamiento de Imagen Asistido por Computador/métodos , Angiografía por Resonancia Magnética/métodos , Adulto , Anciano , Anciano de 80 o más Años , Malformaciones Vasculares del Sistema Nervioso Central/terapia , Embolización Terapéutica , Femenino , Estudios de Seguimiento , Hemodinámica/fisiología , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad
8.
Int J Oral Maxillofac Surg ; 35(12): 1162-3, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17008055

RESUMEN

An interesting case of a trauma-induced tender mass of the buccal mucosa in a 45-year-old man was presented. Following surgery, the patient was relieved from pain. Microscopically, the mature adipose tissue is unique in that it contained a single enlarged Pacinian corpuscle near the deep margin. This is the hitherto undescribed intraoral lesion of Pacinian neuroma in the herniated buccal fat pad.


Asunto(s)
Tejido Adiposo/patología , Neoplasias de la Boca/patología , Neuroma/patología , Corpúsculos de Pacini/patología , Humanos , Masculino , Persona de Mediana Edad , Mucosa Bucal/patología
9.
Biochim Biophys Acta ; 1216(3): 409-16, 1993 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-8268221

RESUMEN

To identify the essential sequence of the promoter of the human thymidylate synthase (hTS) gene, deletion mutants were constructed and assayed for promoter activity. The essential sequence was located within 65 bp upstream from the major cap site and a sequence that reduces the promoter activity was found in a region upstream from the essential promoter sequence. We previously identified two DNA-binding nuclear factors, NF-TS2 and NF-TS3, that bind to a region around the site of initiation of translation of the hTS gene. In this study, we confirmed the binding site of these factors by gel mobility shift analysis and found that NF-TS2 is the major factor that binds to the hTS gene in HeLa cells, whereas NF-TS3 is the major factor in the TIG-1 line of human fibroblast cells. To clarify the function of these factors, we examined the effects of the binding of these factors on the promoter activity. Our findings suggest that the binding of NF-TS2 enhances the promoter activity of the hTS gene in HeLa cells, whereas the binding of NF-TS3 represses the activity of the same promoter in TIG-1 cells.


Asunto(s)
Hominidae/genética , Proteínas Nucleares/metabolismo , Regiones Promotoras Genéticas , Secuencias Reguladoras de Ácidos Nucleicos , Timidilato Sintasa/biosíntesis , Timidilato Sintasa/genética , Animales , Secuencia de Bases , Sitios de Unión , Cartilla de ADN , ADN de Neoplasias/metabolismo , Células HeLa , Humanos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Mapeo Restrictivo , Eliminación de Secuencia
10.
Aust Dent J ; 60(3): 408-11, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25302816

RESUMEN

Methotrexate (MTX) is the primary drug used in the management of rheumatoid arthritis (RA) and other immune-mediated inflammatory diseases. MTX is a strong immunosuppressive agent and has been reported to cause iatrogenic immunodeficiency-associated lymphoproliferative disorders (LPDs). Stomatitis caused by MTX-related cytotoxicity may occur, but gingival MTX-related LPDs are rare. In this article we present a case of gingival MTX-related LPD in a 60-year-old male with RA. The local findings of the gingival ulceration and alveolar bone exposure were similar to those of bisphosphonate-related osteonecrosis of the jaw. However, he had never received bisphosphonate therapy. The biopsy specimen of the gingival lesion was diagnosed as diffuse large B-cell lymphoma with Epstein-Barr virus positivity. Immediate withdrawal of MTX resulted in marked remission of the LPD.


Asunto(s)
Artritis Reumatoide/tratamiento farmacológico , Infecciones por Virus de Epstein-Barr/diagnóstico , Neoplasias Gingivales/virología , Herpesvirus Humano 4/aislamiento & purificación , Inmunosupresores/efectos adversos , Linfoma de Células B Grandes Difuso/virología , Metotrexato/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Úlceras Bucales/virología , Osteonecrosis/virología
11.
FEBS Lett ; 344(1): 31-4, 1994 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-8181559

RESUMEN

Codon recognition by Escherichia coli tRNA(Leu)4 and tRNA(Leu)5 was investigated by analysis of the competition between two aminoacyl-tRNA species in an in vitro protein synthesis. Both tRNA species strictly obey the wobble rule when they are in competition with other tRNA species. This is probably due to the post-transcriptional modifications at the first position of the anticodon of these tRNA(Leu) species, supporting the proposal that the conformational rigidity of post-transcriptionally modified pyrimidine nucleotides guarantees the correct codon recognition.


Asunto(s)
Codón , Escherichia coli/genética , ARN de Transferencia de Leucina/metabolismo , Secuencia de Aminoácidos , Anticodón , Secuencia de Bases , Sitios de Unión , Unión Competitiva , Cloranfenicol O-Acetiltransferasa/química , Cloranfenicol O-Acetiltransferasa/genética , Enlace de Hidrógeno , Datos de Secuencia Molecular , Conformación de Ácido Nucleico , Fenilalanina/genética
12.
FEBS Lett ; 469(1): 39-43, 2000 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-10708752

RESUMEN

We have determined the complete cDNA sequences of fresh water rod opsin gene (fwo) and deep-sea rod opsin gene (dso) from Japanese eel Anguilla japonica. The cDNA clones of fwo and dso consisted of 1437 and 1497 nucleotides, respectively. The predicted opsins of both genes consisted of 352 amino acid residues. Southern blot and PCR analyses of genomic DNA indicated that the Japanese eel genome contains only one fwo and one dso and they are intronless. Quantitative RT-PCR analyses revealed that the expression of fwo decreases with sexual maturation while that of dso increases.


Asunto(s)
Anguilla/genética , Regulación del Desarrollo de la Expresión Génica/genética , Opsinas de Bastones/genética , Animales , Southern Blotting , Clonación Molecular , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Maduración Sexual/genética
13.
Thromb Haemost ; 42(2): 726-33, 1979 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-92068

RESUMEN

Protease-like activity which split plasminogen-free fibrin was demonstrated in 2 M KSCN extracts of the lung and spleen of conventional rats. The activity was virtually undetectable in tissue extracts from germ-free rats. The extracts from the conventional rat tissues split fibrin and fibrinogen remarkably at neutral pH, but not casein, when examined using fibrin, fibrinogen-agar and casein-agar plates. The fibrinolytic activity was inhibited by STI and DFP, indicating a serine protease nature. The activity was not inhibited by TLCK, t-AMCHA or dansyl-L-arginine-methylpiperidine amide (a selective synthetic thrombin inhibitor, OM189). It was neither activated nor inhibited by cysteine, KCN or iodoacetic acid. The results obtained indicate that the protease-like activity of the lung and spleen extracted with 2 M KSCN from conventional rats has properties which differ from those of trypsin, plasmin, plasminogen-activator, thrombin, and cathepsin A, B and C.


Asunto(s)
Fibrinólisis , Vida Libre de Gérmenes , Pulmón/fisiología , Bazo/fisiología , Extractos de Tejidos/farmacología , Animales , Electroforesis en Acetato de Celulosa , Fibrina/metabolismo , Fibrinógeno , Activadores Plasminogénicos/fisiología , Ratas , gammaglobulinas
14.
Thromb Haemost ; 53(3): 323-7, 1985 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-3901390

RESUMEN

The behavior of direct fibrinolytic (non-plasmin) proteinase activity and plasminogen-activator activity in the lung and spleen was investigated in rats after a single intravenous injection of bacterial endotoxin, and the influence of thrombin inhibitors on the effects of the endotoxin was assessed. The non-plasmin fibrinolytic activity was markedly increased following a decrease of plasminogen-activator in the lung. In addition, variations in hematological parameters, i.e. a decrease of platelet count, fibrinogen level and antithrombin III, and an increase of blood urea nitrogen and euglobulin fibrinolytic activity, were induced by the injection, indicating the occurrence of disseminated intravascular coagulation. In comparative studies on the effects of the endotoxin injection and thrombin infusion, in the lung and spleen an increase of fibrinolytic proteinase activity was induced in a similar manner; the plasminogen-activator activity in the lung was decreased by the endotoxin injection but not decreased by the thrombin infusion. In prevention studies with heparin and MD-805, the latter was found to prevent the decrease of either fibrinogen or platelet count. However, the former failed to prevent the decrease of platelet count although that of the fibrinogen level was prevented. Heparin and MD-805 exerted no preventive effect on the endotoxin-induced variations of proteinase activity and plasminogen-activator activity in the lung.


Asunto(s)
Endopeptidasas/metabolismo , Endotoxinas/farmacología , Fibrinolíticos/metabolismo , Lipopolisacáridos/farmacología , Pulmón/metabolismo , Ácidos Pipecólicos/farmacología , Activadores Plasminogénicos/metabolismo , Bazo/metabolismo , Animales , Arginina/análogos & derivados , Pruebas de Coagulación Sanguínea , Escherichia coli , Femenino , Fibrinógeno/análisis , Pulmón/efectos de los fármacos , Recuento de Plaquetas , Ratas , Ratas Endogámicas , Bazo/efectos de los fármacos , Sulfonamidas , Trombina/antagonistas & inhibidores
15.
Thromb Haemost ; 45(2): 121-6, 1981 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-7196095

RESUMEN

Milk plasminogen-activator was partially purified from human transitional milk collected at about 10 days after delivery, by a five-step procedure involving chloroform treatment, ammonium sulfate precipitation, and column chromatography on Sephadex G-150, CM Sephadex C-50 and DEAE Sephadex A-50. This gave milk-activator with a maximum purification factor of about 2,400-fold with respect to the skimmed milk. The CM Sephadex-step preparation showed, on polyacrylamide gel electrophoresis, a single plasminogen-activator activity band located between the bands of albumin and prealbumin of human serum. This preparation exhibited no kinin forming activity. The activator hydrolyzed acetyl-glycyl-L-lysine methyl ester with similar order kinetic constants to urokinase, and was inhibited strongly by diisopropylfluorophosphate. The molecular weight of the activator as estimated by gel filtration was approximately 86,000, the isoelectric points as estimated by gel isoelectric focusing were pH 7.2, 6.9 and 6.6, and the activator activity was not quenched by antiurokinase globulin, indicating that the milk-activator is a different entity from urokinase.


Asunto(s)
Leche Humana , Activadores Plasminogénicos/aislamiento & purificación , Sulfato de Amonio/farmacología , Arginina/análogos & derivados , Arginina/metabolismo , Cloroformo/farmacología , Cromatografía en Gel , Cromatografía por Intercambio Iónico , Electroforesis en Gel de Poliacrilamida , Femenino , Calor , Humanos , Concentración de Iones de Hidrógeno , Hidrólisis , Focalización Isoeléctrica , Isoflurofato/farmacología , Cininas/biosíntesis , Peso Molecular , Activador de Plasminógeno de Tipo Uroquinasa/inmunología
16.
J Biochem ; 80(1): 69-71, 1976 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-965367

RESUMEN

We have previously suggested the involvement of both hydrogen binding and hydrophobic bonding in the adsorption of sulfanilamide on Bio-Gel beads. In the present study, we closely examined the concentration dependence of the binding curve and our proposed binding model has been corroborated. For comparison, binding parameters and thermodynamic data pertaining to the sulfanilamide-Sephadex system have been also evaluated.


Asunto(s)
Geles , Sulfanilamidas , Adsorción , Sitios de Unión , Dextranos , Termodinámica
17.
J Biochem ; 106(1): 1-4, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2476429

RESUMEN

A long L1 repetitive sequence (3.6 kilobase pairs) was found in the third intron of the human thymidylate synthase gene. This L1 family sequence is unique in that it possesses the longest open reading frame (1.7 kilobase pairs) of all L1 family members identified in sequences associated with specific genes that have been cloned thus far. Furthermore, the amino acid sequence deduced from the open reading frame of the L1 sequence was found to be highly homologous (90%) to that encoded by a known human teratocarcinoma L1 RNA species, and to contain several blocks of sequences homologous to ones in RNA-dependent DNA polymerases of various origins.


Asunto(s)
Timidilato Sintasa/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Southern Blotting , Codón , ADN/ultraestructura , Humanos , Intrones , Ratones , Datos de Secuencia Molecular , ARN/genética , Secuencias Repetitivas de Ácidos Nucleicos , Homología de Secuencia de Ácido Nucleico
18.
Toxicol Sci ; 56(2): 297-302, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10910987

RESUMEN

The correlation between the mutation at codon 61 of the H-ras gene and the expression of the Bcl-2 protein was investigated in naturally occurring hepatocellular proliferative lesions in B6C3F1 mice. Specimens of histologically diagnosed neoplastic or preneoplastic lesions of the liver, obtained from the control mice used for 2-year carcinogenicity studies, were examined by immunohistochemical techniques. All of 25 lesions confirmed to be hepatocellular carcinomas stained positive for the Bcl-2 protein. Three of 12 foci of cellular alterations, as well as 24 of 42 hepatocellular adenomas, stained weakly positive. Bcl-2 protein was expressed to a greater degree in hepatocellular carcinomas as opposed to adenomas and confirmed by Western blot analysis. Seven of 18 hepatocellular adenomas that stained positive for Bcl-2 and three of 16 hepatocellular adenomas that stained negative had a mutation at codon 61 of the H-ras gene. Overexpression of Bcl-2 protein is likely to enhance the malignant turnover of the neoplastic cells, following a mutation at codon 61 of the H-ras gene particularly. These findings suggest that Bcl-2 overexpression and the mutation at codon 61 of the H-ras gene may be critical factors in the development of naturally occurring hepatocellular tumors in B6C3F1 mice.


Asunto(s)
Genes ras/fisiología , Neoplasias Hepáticas/etiología , Hígado/patología , Proteínas Proto-Oncogénicas c-bcl-2/fisiología , Animales , División Celular , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Ratones , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Antígeno Nuclear de Célula en Proliferación/análisis
19.
Ann Thorac Surg ; 22(1): 91-2, 1976 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-938143

RESUMEN

A new electric cutter for surgical prostheses has been developed and was compared with surgical scissors for efficacy. This comparison of the two methods was done by cutting the edges of nine popular prostheses. It was concluded from gross and microscopical results after pulling both edges of the grafts cut by the two methods that the electric cutter is much more effective for surgical prostheses.


Asunto(s)
Prótesis Vascular/instrumentación , Complicaciones Posoperatorias/prevención & control , Humanos , Propiedades de Superficie
20.
Thromb Res ; 82(1): 79-86, 1996 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-8731512

RESUMEN

In our studies, designed to synthesize an active center-directed plasmin (PL) inhibitor, N-(4-aminomethylbenzoyl)-4-(3-picolyloxy)-L-phenylalanine n-hexylamide dihydrochloride (PASI-535) was found. We characterized PASI-535 and analyzed the actions of PL, comparing with those of PASI-535 and tranexamic acid (t-AMCHA). (1) PASI-535 strongly inhibited not only fibrinolysis (IC50: 2.9 x 10(-6) M) but also amidolysis (Ki value: 2.9 x 10(-6) M) and fibrinogenolysis (IC50: 4.5 x 10(-6) M) induced by PL. While t-AMCHA which strongly inhibited fibrinolysis (IC50: 6.0 x 10(-5) M), rarely inhibited amidolysis (Ki value: 4.0 x 10(-2) M) and fibrinogenolysis (IC50: 1.0 x 10(-2) M). (2) PL is able to liberate kinins by degrading kininogen. This kinin-generation by PL was inhibited by 2 x 10(-5) M PASI-535. However, it was little inhibited even by 1 x 10(-3) M t-AMCHA. (3) The inhibitory effect of PASI-535 and t-AMCHA on tumor growth was studied. In sarcoma-180 bearing mice, ascites retention and the increase of tumor cells were markedly suppressed by subcutaneous injection of PASI-535, either 30 mg/kg/day or 50 mg/kg/day, for 5 days, and the inhibitory effect was dose-dependent. Although t-AMCHA also reduced both ascites retention and the increase of tumor cells, it needed approximately 40 times (2 g/kg/day) the amount of PASI-535 to exert these effects. PASI-535 may be a useful tool in analyzing the multiplicity of PL actions. Moreover, PASI-535 can be used as an antifibrinolytic drug which has a mechanism of function different from that of t-AMCHA.


Asunto(s)
Inhibidores Enzimáticos/uso terapéutico , Fibrinolisina/antagonistas & inhibidores , Fenilalanina/análogos & derivados , Sarcoma Experimental/tratamiento farmacológico , Secuencia de Aminoácidos , Animales , Sitios de Unión , Fibrinólisis/efectos de los fármacos , Cinética , Cininas/metabolismo , Ratones , Datos de Secuencia Molecular , Péptidos/química , Fenilalanina/farmacología , Especificidad por Sustrato
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