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1.
Amino Acids ; 43(3): 1331-7, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22203366

RESUMO

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.


Assuntos
Afeto/efeitos dos fármacos , Resolução de Problemas/efeitos dos fármacos , Estresse Psicológico/tratamento farmacológico , Tranquilizantes/administração & dosagem , Ácido gama-Aminobutírico/administração & dosagem , Administração Oral , Adulto , Ritmo alfa/efeitos dos fármacos , Ritmo beta/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Estudos Cross-Over , Ecoencefalografia , Feminino , Humanos , Masculino , Método Simples-Cego , Estatísticas não Paramétricas , Estresse Psicológico/diagnóstico por imagem , Resultado do Tratamento , Adulto Jovem
2.
Phys Rev Lett ; 104(24): 247201, 2010 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-20867330

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-18221325

RESUMO

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.


Assuntos
Processo Alveolar/patologia , Ameloblastoma/patologia , Neoplasias Maxilomandibulares/patologia , Adulto , Epitélio/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
4.
J Oral Pathol Med ; 37(1): 43-9, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18154577

RESUMO

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.


Assuntos
Angiomioma/patologia , Tumor Glômico/patologia , Hemangiopericitoma/patologia , Neoplasias Maxilomandibulares/patologia , Neoplasias Bucais/patologia , Miofibroma/patologia , Actinas/análise , Adulto , Idoso , Angiomioma/química , Antígenos CD34/análise , Desmina/análise , Feminino , Tumor Glômico/química , Hemangiopericitoma/química , Humanos , Técnicas Imunoenzimáticas , Neoplasias Maxilomandibulares/química , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/química , Miofibroma/química , Neoplasias de Tecido Muscular/classificação , Neoplasias de Tecido Vascular/classificação
5.
Acta Neurochir (Wien) ; 150(8): 847-8, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18574549

RESUMO

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.


Assuntos
Vértebras Cervicais/irrigação sanguínea , Embolização Terapêutica , Neurofibromatose 1/complicações , Artéria Vertebral , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Síndromes de Compressão Nervosa/diagnóstico , Síndromes de Compressão Nervosa/etiologia , Síndromes de Compressão Nervosa/terapia , Neurofibromatose 1/diagnóstico , Exame Neurológico , Raízes Nervosas Espinhais/patologia , Tomografia Computadorizada por Raios X , Artéria Vertebral/patologia
6.
Neuroscience ; 146(2): 494-8, 2007 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-17368741

RESUMO

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.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proliferação de Células , Ritmo Circadiano/fisiologia , Expressão Gênica/fisiologia , Neurônios/fisiologia , Proteínas Nucleares/metabolismo , Células-Tronco/metabolismo , Fatores de Transcrição/metabolismo , Animais , Bromodesoxiuridina/metabolismo , Proteínas de Ciclo Celular/genética , Proliferação de Células/efeitos dos fármacos , Embrião de Mamíferos , Fator de Crescimento Epidérmico/farmacologia , Camundongos , Camundongos Endogâmicos ICR , Neurônios/efeitos dos fármacos , Proteínas Nucleares/genética , Proteínas Circadianas Period , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Células-Tronco/efeitos dos fármacos , Fatores de Tempo , Fatores de Transcrição/genética
7.
AJNR Am J Neuroradiol ; 27(2): 264-9, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16484389

RESUMO

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.


Assuntos
Angiografia Digital/métodos , Malformações Vasculares do Sistema Nervoso Central/diagnóstico , Processamento de Imagem Assistida por Computador/métodos , Angiografia por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Malformações Vasculares do Sistema Nervoso Central/terapia , Embolização Terapêutica , Feminino , Seguimentos , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
8.
Int J Oral Maxillofac Surg ; 35(12): 1162-3, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17008055

RESUMO

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.


Assuntos
Tecido Adiposo/patologia , Neoplasias Bucais/patologia , Neuroma/patologia , Corpúsculos de Pacini/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/patologia
9.
Biochim Biophys Acta ; 1216(3): 409-16, 1993 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-8268221

RESUMO

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.


Assuntos
Hominidae/genética , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas , Sequências Reguladoras de Ácido Nucleico , Timidilato Sintase/biossíntese , Timidilato Sintase/genética , Animais , Sequência de Bases , Sítios de Ligação , Primers do DNA , DNA de Neoplasias/metabolismo , Células HeLa , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Mapeamento por Restrição , Deleção de Sequência
10.
Aust Dent J ; 60(3): 408-11, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25302816

RESUMO

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.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Infecções por Vírus Epstein-Barr/diagnóstico , Neoplasias Gengivais/virologia , Herpesvirus Humano 4/isolamento & purificação , Imunossupressores/efeitos adversos , Linfoma Difuso de Grandes Células B/virologia , Metotrexato/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Úlceras Orais/virologia , Osteonecrose/virologia
11.
FEBS Lett ; 344(1): 31-4, 1994 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-8181559

RESUMO

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.


Assuntos
Códon , Escherichia coli/genética , RNA de Transferência de Leucina/metabolismo , Sequência de Aminoácidos , Anticódon , Sequência de Bases , Sítios de Ligação , Ligação Competitiva , Cloranfenicol O-Acetiltransferase/química , Cloranfenicol O-Acetiltransferase/genética , Ligação de Hidrogênio , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Fenilalanina/genética
12.
FEBS Lett ; 469(1): 39-43, 2000 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-10708752

RESUMO

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.


Assuntos
Anguilla/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Opsinas de Bastonetes/genética , Animais , Southern Blotting , Clonagem Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Maturidade Sexual/genética
13.
Thromb Haemost ; 42(2): 726-33, 1979 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-92068

RESUMO

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.


Assuntos
Fibrinólise , Vida Livre de Germes , Pulmão/fisiologia , Baço/fisiologia , Extratos de Tecidos/farmacologia , Animais , Eletroforese em Acetato de Celulose , Fibrina/metabolismo , Fibrinogênio , Ativadores de Plasminogênio/fisiologia , Ratos , gama-Globulinas
14.
Thromb Haemost ; 45(2): 121-6, 1981 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-7196095

RESUMO

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.


Assuntos
Leite Humano , Ativadores de Plasminogênio/isolamento & purificação , Sulfato de Amônio/farmacologia , Arginina/análogos & derivados , Arginina/metabolismo , Clorofórmio/farmacologia , Cromatografia em Gel , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Feminino , Temperatura Alta , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Focalização Isoelétrica , Isoflurofato/farmacologia , Cininas/biossíntese , Peso Molecular , Ativador de Plasminogênio Tipo Uroquinase/imunologia
15.
Thromb Haemost ; 53(3): 323-7, 1985 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-3901390

RESUMO

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.


Assuntos
Endopeptidases/metabolismo , Endotoxinas/farmacologia , Fibrinolíticos/metabolismo , Lipopolissacarídeos/farmacologia , Pulmão/metabolismo , Ácidos Pipecólicos/farmacologia , Ativadores de Plasminogênio/metabolismo , Baço/metabolismo , Animais , Arginina/análogos & derivados , Testes de Coagulação Sanguínea , Escherichia coli , Feminino , Fibrinogênio/análise , Pulmão/efeitos dos fármacos , Contagem de Plaquetas , Ratos , Ratos Endogâmicos , Baço/efeitos dos fármacos , Sulfonamidas , Trombina/antagonistas & inibidores
16.
J Biochem ; 80(1): 69-71, 1976 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-965367

RESUMO

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.


Assuntos
Géis , Sulfanilamidas , Adsorção , Sítios de Ligação , Dextranos , Termodinâmica
17.
J Biochem ; 106(1): 1-4, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2476429

RESUMO

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.


Assuntos
Timidilato Sintase/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Southern Blotting , Códon , DNA/ultraestrutura , Humanos , Íntrons , Camundongos , Dados de Sequência Molecular , RNA/genética , Sequências Repetitivas de Ácido Nucleico , Homologia de Sequência do Ácido Nucleico
18.
Toxicol Sci ; 56(2): 297-302, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10910987

RESUMO

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.


Assuntos
Genes ras/fisiologia , Neoplasias Hepáticas/etiologia , Fígado/patologia , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Animais , Divisão Celular , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Antígeno Nuclear de Célula em Proliferação/análise
19.
Ann Thorac Surg ; 22(1): 91-2, 1976 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-938143

RESUMO

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.


Assuntos
Prótese Vascular/instrumentação , Complicações Pós-Operatórias/prevenção & controle , Humanos , Propriedades de Superfície
20.
Thromb Res ; 82(1): 79-86, 1996 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-8731512

RESUMO

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.


Assuntos
Inibidores Enzimáticos/uso terapêutico , Fibrinolisina/antagonistas & inibidores , Fenilalanina/análogos & derivados , Sarcoma Experimental/tratamento farmacológico , Sequência de Aminoácidos , Animais , Sítios de Ligação , Fibrinólise/efeitos dos fármacos , Cinética , Cininas/metabolismo , Camundongos , Dados de Sequência Molecular , Peptídeos/química , Fenilalanina/farmacologia , Especificidade por Substrato
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