Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 49
Filtrar
1.
Histol Histopathol ; 28(1): 127-32, 2013 01.
Artigo em Inglês | MEDLINE | ID: mdl-23233065

RESUMO

Intrauterine growth restriction (IUGR) is the leading cause of fetal mortality and morbidity. As an etiology, each of placental findings, maternal factors and fetal factors has been reported to be associated with IUGR, although a comprehensive approach to examine all of these parameters as a cause of IUGR has not been reported. In the present study, therefore, we comprehensively examined the placental findings and maternal and fetal factors in the cases of IUGR (n=257, mean maternal age, 30 years; gestational weeks, 34 weeks) and normal growth pregnancies (n=258, mean maternal age, 30 years; gestational weeks, 33 weeks), and determined risk factors for IUGR. The prevalence of pregnancy hypertension (PHT) (19% vs. 8%, P<0.01), smoking habit (3% vs. 0.7%, P<0.05) and fetal anomaly (3.5% vs. 0.8%, P<0.05) were higher in IUGR cases than normal growth pregnancies. Pathologically, the prevalence of infarction (33% vs. 14%, P<0.05), fetal vessel thrombosis (22% vs. 6%, P<0.001) and chronic villitis (11% vs. 3%, P<0.001) were higher in IUGR cases than those in normal growth pregnancies. A multivariable regression analysis revealed that maternal factors (PHT), fetal factors (anomaly), and placental findings (infarction, fetal vessel thrombosis, and chronic villitis) are independently associated with increased risk of IUGR (all P<0.01).


Assuntos
Retardo do Crescimento Fetal/etiologia , Retardo do Crescimento Fetal/patologia , Placenta/patologia , Povo Asiático , Feminino , Retardo do Crescimento Fetal/epidemiologia , Feto/patologia , Humanos , Gravidez , Complicações na Gravidez/epidemiologia , Prevalência , Fatores de Risco
2.
Leukemia ; 26(10): 2216-23, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22469782

RESUMO

Ten-Eleven-Translocation 2 (TET2) is an enzyme that catalyzes the conversion of 5-methylcytosine into 5-hydroxymethylcytosine (5-hmC) and thereby alters the epigenetic state of DNA; somatic loss-of-function mutations of TET2 are frequently observed in patients with diverse myeloid malignancies. To study the function of TET2 in vivo, we analyzed Ayu17-449 (TET2(trap)) mice, in which a gene trap insertion in intron 2 of TET2 reduces TET2 mRNA levels to about 20% of that found in wild-type (WT) mice. TET2(trap/trap) mice were born at Mendelian frequency but died at a high rate by postnatal day 3, indicating the essential role of TET2 for survival. Loss of TET2 results in an increase in the number of hematopoietic stem cells (HSCs)/progenitors in the fetal liver, and TET2(trap/trap) HSCs exhibit an increased self-renewal ability in vivo. In competitive transplantation assays, TET2(trap/trap) HSCs possess a competitive growth advantage over WT HSCs. These data indicate that TET2 has a critical role in survival and HSC homeostasis.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Células-Tronco Hematopoéticas/fisiologia , Homeostase , Proteínas Proto-Oncogênicas/fisiologia , Animais , Sobrevivência Celular , Dioxigenases , Hematopoese , Células-Tronco Hematopoéticas/citologia , Janus Quinase 2/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/análise
3.
Leukemia ; 26(6): 1238-46, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22289924

RESUMO

Cell adhesion molecule 1 (CADM1/TSLC1) was recently identified as a novel cell surface marker for adult T-cell leukemia/lymphoma (ATLL). In this study, we developed various antibodies as diagnostic tools to identify CADM1-positive ATLL leukemia cells. In flow cytometric analysis, the percentages of CD4(+)CADM1(+) double-positive cells correlated well with both the percentages of CD4(+)CD25(+) cells and with abnormal lymphocytes in the peripheral blood of patients with various types of ATLL. Moreover, the degree of CD4(+)CADM1(+) cells over 1% significantly correlated with the copy number of the human T-lymphotropic virus type 1 (HTLV-1) provirus in the peripheral blood of HTLV-1 carriers and ATLL patients. We also identified a soluble form of CADM1 in the peripheral blood of ATLL patients, and the expression levels of this form were correlated with the levels of soluble interleukin 2 receptor alpha. Moreover, lymphomas derived from ATLL were strongly and specifically stained with a CADM1 antibody. Thus, detection of CD4(+)CADM1(+) cells in the peripheral blood, measurement of serum levels of soluble CADM1 and immunohistochemical detection of CADM1 in lymphomas would be a useful set of markers for disease progression in ATLL and may aid in both the early diagnosis and measurement of treatment efficacy for ATLL.


Assuntos
Moléculas de Adesão Celular/metabolismo , Infecções por HTLV-I/diagnóstico , Imunoglobulinas/metabolismo , Leucemia-Linfoma de Células T do Adulto/diagnóstico , Leucemia-Linfoma de Células T do Adulto/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Adulto , Estudos de Casos e Controles , Molécula 1 de Adesão Celular , Moléculas de Adesão Celular/imunologia , DNA Viral/genética , Progressão da Doença , Citometria de Fluxo , Infecções por HTLV-I/genética , Infecções por HTLV-I/virologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Humanos , Técnicas Imunoenzimáticas , Imunoglobulinas/imunologia , Leucemia-Linfoma de Células T do Adulto/virologia , Linfócitos/citologia , Linfócitos/metabolismo , Provírus/genética , Reação em Cadeia da Polimerase em Tempo Real , Carga Viral
4.
Cytopathology ; 22(5): 313-7, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21039979

RESUMO

OBJECTIVE: Smear preparations are useful tools from which to diagnose brain tumours intraoperatively. Although vascular proliferation is histologically a key feature of high-grade astrocytoma, the characteristics of tumour vessels in smear preparations have not been determined. METHODS: We examined the density and morphological parameters (area, width, nuclear layer and branches of vessel wall) of tumour vessels in squash smears of 43 primary astrocytomas (grade II diffuse astrocytomas, n=9; grade III anaplastic astrocytomas, n=13; grade IV glioblastomas, n=21) and normal brain tissues (n=11). RESULTS: Vessel density and all morphological parameters were significantly higher in grade IV than in the other grades of tumours and in normal brain tissue. Vessel area, width and nuclear layer were greater in grade III than in normal brain tissue. The sensitivity and specificity of these vessel parameters for astrocytomas were 75-100% and 82-100%, respectively. CONCLUSIONS: Tumour vessel evaluations from squash smears provide useful information for the intraoperative diagnosis and grading of astrocytic tumours.


Assuntos
Astrocitoma/irrigação sanguínea , Neoplasias Encefálicas/irrigação sanguínea , Glioblastoma/irrigação sanguínea , Neovascularização Patológica/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Astrocitoma/patologia , Neoplasias Encefálicas/patologia , Feminino , Glioblastoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias
5.
Cytopathology ; 21(2): 103-10, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19863615

RESUMO

OBJECTIVE: Extracellular matrix metalloproteinase inducer (EMMPRIN) and its induced matrix metalloproteinases (MMPs) play a crucial role in tumour progression, invasion and metastasis. EMMPRIN expression has been demonstrated in several tumours, but its expression profile in thyroid cancer remains unclear. METHODS: We evaluated the expression profile of EMMPRIN at various stages of differentiation of thyroid carcinoma, including 20 cases of well-differentiated papillary carcinoma (WDPC), 15 cases of papillary carcinoma with a poorly differentiated carcinoma component (PC/PDC) and four cases with an undifferentiated carcinoma (UDC) component, using paraffin-embedded sections for immunohistochemical stains. Also, we used 32 fine needle aspiration cytology and imprint smears from the same cases for immunocytochemical stains. The staining results were evaluated with a scoring system. RESULTS: Immunohistochemical staining showed that EMMPRIN expression was absent or weak in almost all WDPC specimens, whereas it was moderate or strong in PDC and UDC components. In tumours that showed a gradual morphological transformation from WDPC to PDC components, the expression of EMMPRIN was progressively stronger from the areas of WDPC to those of PDC. WDPC, PC/PDC and UDC had expression scores of 4.9, 45.0 and 245.7, respectively. Results of immunocytochemical staining showed almost the same staining profile as those of immunohistochemical staining. The cytological atypia of EMMPRIN-positive cells was greater than that of negative cells. CONCLUSION: These results indicated that EMMPRIN expression correlates significantly with the degree of dedifferentiation of thyroid carcinoma. This study demonstrates the feasibility of expression of EMMPRIN using fine needle aspiration samples. Therefore, immunocytochemical analysis of EMMPRIN may be a novel aid to evaluate the differentiation of thyroid carcinoma.


Assuntos
Adenocarcinoma Papilar/patologia , Basigina/metabolismo , Neoplasias da Glândula Tireoide/patologia , Adenocarcinoma Papilar/metabolismo , Biomarcadores Tumorais/metabolismo , Biópsia por Agulha Fina , Desdiferenciação Celular , Humanos , Imuno-Histoquímica , Neoplasias da Glândula Tireoide/metabolismo
6.
Br J Dermatol ; 154(5): 983-7, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16634907

RESUMO

We describe a 2-year-old girl with recurrent giant cell fibroblastoma (GCF) of the postsacrococcygeal region. Both the initial and recurrent tumours contained solid and angiectoid areas. The former was composed of loosely arranged wavy spindle cells and giant cells with a well-vascularized myxoid to collagenous stroma. The angiectoid spaces were often lined by multinucleated giant cells. Immunohistochemically, the tumour cells and small vessels in the tumour tissue were positive for platelet-derived growth factor (PDGF) alpha and beta receptors. Molecular analysis revealed fusion of collagen type Ialpha1 exon 26 with PDGF-B chain exon 2 that induced unscheduled production of PDGF-BB. These findings suggest that PDGF and its receptors significantly contribute to the development of GCF in both an autocrine and a paracrine manner.


Assuntos
Dermatofibrossarcoma/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Neoplasias Cutâneas/metabolismo , Sequência de Bases , Dermatofibrossarcoma/patologia , Dermatofibrossarcoma/cirurgia , Feminino , Humanos , Lactente , Dados de Sequência Molecular , Proteínas de Neoplasias/genética , Recidiva Local de Neoplasia/metabolismo , Proteínas de Fusão Oncogênica/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Região Sacrococcígea , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgia
7.
Heart ; 91(4): 526-30, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15772220

RESUMO

OBJECTIVE: To determine the proportion of platelets and fibrin in coronary thrombi. DESIGN: Immunohistochemical and morphometric means to examine the coronary arteries of 31 patients who died of acute myocardial infarction. RESULTS: Fresh thrombi were detected in the feeding arteries of infarction areas in 23 cases (74%) and were associated with plaque rupture in 18 (78%) and plaque erosion in 5 (22%). An immunohistochemical study showed that the thrombi consisted of a mixture of fibrin and platelets as well as some other types of blood cells. The fibrin and platelet positive areas in the thrombi associated with plaque rupture accounted for 74 (19)% and 35 (20)% (p < 0.01) and those associated with erosion accounted for 51 (6)% and 70 (21)%, respectively, of the total areas. Areas of positive immunoreactivity for tissue factor and C reactive protein were also significantly greater in ruptured than in eroded plaques. CONCLUSION: These results indicate that the proportions of fibrin and of platelets differ in coronary thrombi on ruptured and eroded plaques. Higher proportions of tissue factor and C reactive protein contribute more significantly to thrombus formation on plaque rupture than on plaque erosion.


Assuntos
Plaquetas/patologia , Doença da Artéria Coronariana/metabolismo , Trombose Coronária/metabolismo , Fibrina/análise , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/análise , Proteína C-Reativa/análise , Doença da Artéria Coronariana/patologia , Trombose Coronária/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Tromboplastina/análise
8.
Kyobu Geka ; 57(13): 1185-90, 2004 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-15609654

RESUMO

Mucormycosis is an extremely rare case of pulmonary mycosis, its prognosis is very poor, and known as an opportunistic infection among immunocompromised hosts accompanied with other primary chronic disease. We report here a case of bilateral lower lobectomies carried out by two-stage operation for pulmonary mucormycosis combined with diabetes mellitus (type I) and severe resistance to an antimycobiotics under biblicographical considerations. A 36-year-old female was diagnosed as a diabetes mellitus (type I), and has been administrated with an insulin injection in 1989 at the age of 22-year-old. The patient was suffered a dry cough in June and the bilateral abnormal shadows were pointed out by the chest X-ray film in November, 2002. By transbronchial lung biopsy, Mucor fungus was confirmed in grannulomatous lung specimen. Intravenous injection of amphotericin B could not be continued due to the unavoidable side-effects from this agent. As the lung mass shadow was enlarged increasing and strongly suggested an abscess, formation in its focus, and then the left lower lobectomy was performed as the first step of surgical treatment and the right lower lobectomy was done on the postoperative forty-fourth day as the second step. The postoperative prognosis was considerably uneventful. After bilateral lower lobectomies, the patient could try a walk and go upstairs with a moderate dyspnea. A possible surgical resection should be conducted for the pulmonary mucormycosis, when the medicinal therapy showed an uneffectiveness and/or an infectious lesion was shown as restricted lesion.


Assuntos
Pneumopatias Fúngicas/cirurgia , Mucormicose/cirurgia , Pneumonectomia/métodos , Adulto , Diabetes Mellitus Tipo 1/complicações , Feminino , Humanos , Pneumopatias Fúngicas/patologia , Mucormicose/patologia
9.
Exp Physiol ; 86(5): 543-5, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11571480

RESUMO

The hypotensive and vasorelaxing peptides adrenomedullin (AM) and its gene-related peptide, proadrenomedullin N-terminal 20 peptide (PAMP), were found to be distributed on the surface of the colonic mucosa. AM and PAMP showed dose-dependent antimicrobial activity against E. coli. The results suggest that the novel vasoactive peptides AM and PAMP play an important role in mucosal defence.


Assuntos
Colo/química , Mucosa Intestinal/química , Fragmentos de Peptídeos/análise , Peptídeos/análise , Proteínas/análise , Adrenomedulina , Antibacterianos/química , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Mucosa Intestinal/citologia , Fragmentos de Peptídeos/farmacologia , Peptídeos/farmacologia , Proteínas/farmacologia , Vasodilatadores/análise , Vasodilatadores/farmacologia
10.
J Cutan Pathol ; 28(7): 371-8, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11437944

RESUMO

BACKGROUND: Langerhans cell histiocytosis (LCH) is a proliferating disorder of Langerhans cells (LC) that are characterized by the presence of Birbeck granules. LCH has been considered to be a disease of childhood and there have been limited cases of adult LCH. We report here a fatal case of histiocytic tumor showing Langerhans cell phenotype, arising in the skin of a 74-year-old woman. METHOD: In addition to routine histological and immunohistological sections, electron microscopic examination and human androgen receptor gene (HUMARA) assays were performed. RESULTS: Histological examination revealed a dense dermal infiltrative proliferation of fairly large tumor cells with abundant ill-defined cytoplasms and oval or indented nuclei, in which numerous eosinophils were associated with the tumor nests. Tumor cells were positive with anti-S-100 and CD1a antibodies but negative with HMB-45 antibody or other epithelial or lymphocytic markers. Ultrastructural analysis showed typical Birbeck granules in the cytoplasm of the tumor cells. HUMARA assay of the tumor tissue revealed the nonrandom X inactivation pattern, indicating the clonal proliferation. CONCLUSIONS: We diagnosed this tumor as Langerhans cell histiocytosis with a clonal neoplastic phenotype originated in the skin. Although she demonstrated no recurrence nor metastases for 6 months after surgical resection of primary skin lesion and subsequent radiation therapy, the tumor recurred and extended multisystemically, and she died of multiple organ failure 14 months after initial diagnosis. Therefore, we would like to emphasize this case as LC "sarcoma" or "malignant" LCH.


Assuntos
Histiocitose de Células de Langerhans/genética , Dermatopatias/genética , Idoso , Dorso , Evolução Fatal , Feminino , Mãos , Histiocitose de Células de Langerhans/patologia , Humanos , Fenótipo , Dermatopatias/patologia
11.
Circulation ; 103(4): 570-5, 2001 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-11157724

RESUMO

BACKGROUND: Tissue factor pathway inhibitor (TFPI) is a physiological antagonist of TF. We tested whether a brief irrigation with TFPI protein (rTFPI) or TFPI gene transfer into injured arteries would suppress TF activity and reduce fibroproliferative changes and investigated whether a combination of these methods would show an additive effect. METHODS AND RESULTS: We prepared adenoviruses expressing either TFPI (AdTFPI) or bacterial ss-galactosidase (AdLacZ). Rabbit carotid arteries were balloon-injured and either infected with AdTFPI (or AdLacZ) or irrigated briefly with rTFPI (or saline). After injury, TF activity in arteries increased and was sustained; however, it was suppressed during the initial 24 hours by rTFPI irrigation (but not by gene transfer) and for a substantial period of time by TFPI gene transfer (but not by rTFPI irrigation). Four weeks later, the ratio of the intimal to medial areas was 34.3+/-8.7% (mean+/-SD, n=14) in saline-treated arteries and 33.3+/-4.2% in AdLacZ-infected arteries (P:=NS versus saline). However, it was reduced to 25.5+/-8.5% in rTFPI-irrigated arteries (P:<0.01 versus saline) and to 20.7+/-5.3% in AdTFPI-infected arteries (P:<0.01 versus AdLacZ). With a combination of irrigation and gene transfer, the ratio was further reduced to 12.6+/-4.7% (P:<0.01 versus rTFPI, P:<0.05 versus AdTFPI). Systemic coagulation status was not affected in these animals. CONCLUSIONS: A combination of rTFPI irrigation and TFPI gene transfer overcomes the shortcomings shown by each method when used alone and achieves a full coverage of TF activity suppression, thereby enhancing their therapeutic effects without systemic side effects. This combination may be an effective strategy for the prevention of thrombosis and proliferative changes after angioplasty in humans.


Assuntos
Artérias Carótidas/metabolismo , Lesões das Artérias Carótidas/prevenção & controle , Lipoproteínas/administração & dosagem , Túnica Íntima/efeitos dos fármacos , Adenoviridae/genética , Animais , Artérias Carótidas/patologia , Artérias Carótidas/ultraestrutura , Lesões das Artérias Carótidas/etiologia , Lesões das Artérias Carótidas/fisiopatologia , Cateterismo/efeitos adversos , Fibrina/efeitos dos fármacos , Fibrina/metabolismo , Técnicas de Transferência de Genes , Vetores Genéticos/genética , Lipoproteínas/genética , Lipoproteínas/fisiologia , Masculino , Microscopia Eletrônica de Varredura , Tempo de Tromboplastina Parcial , Agregação Plaquetária/efeitos dos fármacos , Tempo de Protrombina , Coelhos , Irrigação Terapêutica , Tromboplastina/metabolismo , Túnica Íntima/patologia
12.
J Atheroscler Thromb ; 6(2): 55-9, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10872615

RESUMO

We histologically examined the coronary arteries of 52 autopsied cases of the youths (3 to 39 years of age, mean 28.5 years) in Kyushu island, Japan, without clinical events of coronary artery diseases. The coronary artery specimens were taken from the proximal portions of the right coronary artery (Seg. 1), the left anterior descending artery (Seg. 6), and the macroscopically most stenotic region (ST). Atherosclerotic lesions were histologically classified into four types: concentric fibrous, eccentric fibrous, concentric lipid rich, or eccentric lipid-rich type. The degrees of stenosis (< 25%, 25-50%, 50 75%, > 75%) were morphometrically evaluated. The majority of coronary arteries with under 50% stenosis were of the concentric fibrous type. Lipid-rich types of coronary atherosclerosis increased in the coronary arteries with over 50% stenosis and were observed in the Seg. 6 and ST, while 70% of Seg. 1 lesions with over 50% stenosis were of a fibrous type. Serum cholesterol levels of patients with a lipid rich type of coronary atherosclerosis were significantly higher than those with a fibrous type. These results suggested that the early stage of coronary atherosclerosis in Japanese youths is mainly of a concentric fibrous type, which later develops to a lipid rich type. Hypercholesterolemia would promote the progression of atherosclerosis.


Assuntos
Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/fisiopatologia , Adolescente , Adulto , Criança , Pré-Escolar , Doença da Artéria Coronariana/patologia , Doença das Coronárias/epidemiologia , Doença das Coronárias/patologia , Doença das Coronárias/fisiopatologia , Feminino , Humanos , Japão/epidemiologia , Masculino
14.
Histochem Cell Biol ; 112(3): 185-91, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10502065

RESUMO

Adrenomedullin (AM) is a novel hypotensive and vasodilator peptide. We previously examined the localization of AM in human, rat, and porcine tissues using a polyclonal antibody against synthetic human AM[40-52]. We demonstrated that AM is widely distributed in the endocrine and neuroendocrine systems, but not in the heart, kidney, or blood vessels, although high levels of AM mRNA were detected in the latter tissues. In this study, we further investigated the distribution of AM by using two newly developed monoclonal antibodies against synthetic human AM peptides, [12-25] and [46-52]. AM immunoreactivity was observed in cardiac myocytes, vascular smooth muscle cells, endothelial cells, and renal distal and collecting tubules. In addition, AM-immunoreactive (IR) cells were found in mucosal and glandular epithelia of the digestive, respiratory, and reproductive systems, as well as the endocrine and neuroendocrine systems. These findings indicate that AM-IR cells are more widely distributed in human tissues and suggest that AM might play multiple biological roles in humans.


Assuntos
Anti-Hipertensivos/metabolismo , Peptídeos/metabolismo , Vasodilatadores/metabolismo , Adrenomedulina , Anticorpos Monoclonais/imunologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Especificidade de Órgãos , Peptídeos/genética , Peptídeos/imunologia , RNA Mensageiro/análise , Distribuição Tecidual
16.
Am J Physiol ; 276(6): C1391-7, 1999 06.
Artigo em Inglês | MEDLINE | ID: mdl-10362602

RESUMO

Obesity is associated with hyperinsulinemia and elevated concentrations of tumor necrosis factor-alpha (TNF-alpha) in adipose tissue. TNF-alpha has been implicated as an inducer of the synthesis of plasminogen activator inhibitor-1 (PAI-1), the primary physiological inhibitor of fibrinolysis, mediated by plasminogen activators in cultured adipocytes. To identify mechanism(s) through which TNF-alpha induces PAI-1, 3T3-L1 preadipocytes were differentiated into adipocytes and exposed to TNF-alpha for 24 h. TNF-alpha selectively increased the synthesis of PAI-1 without increasing activity of plasminogen activators. Both superoxide (generated by xanthine oxidase plus hypoxanthine) and hydrogen peroxide were potent inducers of PAI-1, and hydroxyl radical scavengers completely abolished the TNF-alpha induction of PAI-1. Exposure of adipocytes to TNF-alpha or insulin alone over 5 days increased PAI-1 production. These agonists exert synergistic effects. Results obtained suggest that TNF-alpha stimulates PAI-1 production by adipocytes, an effect potentiated by insulin, and that adipocyte generation of reactive oxygen centered radicals mediates the induction of PAI-1 production by TNF-alpha. Because induction of PAI-1 by TNF-alpha is potentiated synergistically by insulin, both agonists appear likely to contribute to the impairment of fibrinolytic system capacity typical in obese, hyperinsulinemic patients.


Assuntos
Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Insulina/farmacologia , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Células 3T3 , Animais , Células Cultivadas , Sinergismo Farmacológico , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Tioureia/análogos & derivados , Tioureia/farmacologia
17.
Histopathology ; 34(1): 66-70, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9934587

RESUMO

AIMS: To evaluate the role of activated hepatic stellate cells (HSCs) in hepatic veno-occlusive disease (VOD) after bone marrow transcription (BMT), we studied the distribution and area of activated HSCs by immunohistochemistry for alpha-smooth muscle actin (SMA). METHODS AND RESULTS: We examined the liver of seven autopsy cases with hepatic VOD or without VOD after allogeneic BMT and five autopsy cases without liver disease as a control both microscopically and immunohistochemically. In normal liver tissues, SMA-positive cells were observed around the central veins, while they were more frequently noted along the sinusoidal walls as well as around the central veins in liver tissues with or without VOD after BMT. The area of activated HSCs increased significantly in zones 1 and 2, and more prominently in zone 3 of the liver tissues after BMT than normal liver tissues, and was much larger in zone 3 of liver tissues with VOD. The activated HSCs were immunohistochemically negative for the regulatory contractile proteins (heavy caldesmon and calponin). CONCLUSIONS: These results indicated that the activated HSCs may play an important role in sinusoidal fibrosis and luminal narrowing or occlusion of the central veins in VOD after BMT.


Assuntos
Transplante de Medula Óssea , Hepatopatia Veno-Oclusiva/patologia , Fígado/citologia , Actinas/metabolismo , Adulto , Criança , Feminino , Hepatopatia Veno-Oclusiva/metabolismo , Humanos , Imuno-Histoquímica , Fígado/metabolismo , Fígado/patologia , Masculino , Pessoa de Meia-Idade
18.
Thromb Haemost ; 80(3): 506-11, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9759635

RESUMO

Thrombus formation and neointimal growth are the critical events in restenosis after balloon angioplasty. However, the responses of diseased vessels to injuries caused by balloon angioplasty have not been well examined. We investigated the thrombus formation and neointimal development following the balloon injury to the previously induced neointima in the rabbit aorta and the effects of recombinant tissue factor pathway inhibitor (rTFPI) on these responses. Rabbit thoracic aortas were subjected to injury with a Fogarty 4F balloon catheter at 1.75 atm (first injury), and 4 weeks later the same vessels were subjected to the second injury with a Swan-Ganz 5F balloon catheter at 1.4 atm (mild-injury group) or 1.8 atm (severe-injury group), and immediately after that a retrograde bolus injection of rTFPI (100 microg/kg body weight) or saline was performed into the injured segments via the central tube of the Swan-Ganz catheter. Twenty minutes after the second injury, the injured surfaces were covered with platelet-rich thrombi in the mild-injury group and with fibrin-rich thrombi in the severe-injury group. Damaged intimal smooth muscle cells, which were immunohistochemically positive for tissue factor (TF), were observed beneath the fibrin-rich thrombi. The neointima 4 weeks after the second injury was significantly thicker in the severe-injury group than in the mild-injury group. The bolus infusion of rTFPI markedly inhibited fibrin formation on the injured surfaces, and significantly reduced the neointimal development in the severe-injury group at 4 weeks after the second injury. These results indicate that TF-dependent coagulation pathway is primarily responsible for fibrin-rich thrombus formation and may play an important role in neointimal development following the balloon injury to the rabbit aortic neointima. Additionally the bolus administration of rTFPI to the injured vessels could prevent mural thrombus formation and neointimal growth after balloon angioplasty.


Assuntos
Aorta/patologia , Plaquetas/patologia , Fibrina/metabolismo , Fibrinolíticos/farmacologia , Lipoproteínas/farmacologia , Trombose/metabolismo , Trombose/prevenção & controle , Túnica Íntima/patologia , Animais , Cateterismo , Fibrinolíticos/uso terapêutico , Lipoproteínas/uso terapêutico , Agregação Plaquetária/efeitos dos fármacos , Coelhos , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Trombose/patologia , Túnica Íntima/metabolismo
19.
J Atheroscler Thromb ; 4(3): 135-9, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9730145

RESUMO

TF is a major regulator of coagulation and hemostasis. High levels of TF antigen and activity are detected in atherosclerotic lesions, particularly in the advanced lesions. When the plaques are ruptured or eroded, exposure of cellular and extracellular TF to circulating blood play a pivotal role in mediating fibrin-rich thrombus formation leading to acute coronary syndromes. On the other hand, activation of blood coagulation and deficiency of coagulation inhibitors, without endothelial cell denudation, are considered to be an important factor of thrombogenesis in the microcirculation. The imbalance between TF and TFPI seems to be important in promoting fibrin thrombus formation in the lung of endotoxin induced DIC condition.


Assuntos
Arteriosclerose/induzido quimicamente , Hemostáticos/farmacologia , Tromboplastina/fisiologia , Trombose/induzido quimicamente , Animais , Arteriosclerose/fisiopatologia , Humanos , Coelhos , Ratos , Trombose/fisiopatologia
20.
Atherosclerosis ; 139(2): 265-71, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9712332

RESUMO

Tissue factor (TF) is a primary initiator of the extrinsic pathway of blood coagulation. Recently TF has been shown to be overexpressed in atherosclerotic lesions and it is thought to contribute to the thrombogenicity of the plaques. We studied TF expression in the media and the neointima of rabbit aortas at various intervals after balloon injury. TF protein was immunohistochemically detected in smooth muscle cells (SMCs) of the inner layer of the media at 2 h after injury and was subsequently detected in SMCs in the neointima, whereas no TF expression was detected in the uninjured aortas except for the adventitia. Immunohistochemical and immunoelectron microscopic studies revealed that TF-positive SMCs were of an immature or synthetic phenotype and TF protein was detected in the rough endoplasmic reticulum in SMCs. TF mRNA in the intima and media increased at 2 h after injury and returned to near baseline levels at 12-24 h, whereas TF activity also increased at 2 h and continued at similar levels over the next 72 h. TF mRNA and activity increased markedly at 2-8 weeks after injury. These data suggest that TF is rapidly induced in the medial SMCs and hereafter is constitutively expressed in the neointima. TF expressed in the neointima may contribute to hypercoagulable properties of injured arteries.


Assuntos
Aorta/lesões , Aorta/metabolismo , Cateterismo/efeitos adversos , Tromboplastina/metabolismo , Ferimentos não Penetrantes/metabolismo , Animais , Aorta/patologia , Northern Blotting , Imuno-Histoquímica , Masculino , Microscopia Imunoeletrônica , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , RNA Mensageiro/metabolismo , Coelhos , Tromboplastina/genética , Ferimentos não Penetrantes/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...