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1.
Occup Med (Lond) ; 70(3): 176-182, 2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-32078676

RESUMO

BACKGROUND: Mental health education for managers has typically been conducted using a group format. Few studies have examined the provision of individualized education. AIMS: This study discussed the evaluations and characteristic needs of participants in an individualized mental health education programme while examining avenues for providing such education. METHODS: Eighty-nine individualized education sessions were conducted for managers (87 males, 2 females) with a mean age of 42.6 years (SD = 5.1) at an assembly factory in Japan. Data from anonymous self-administered questionnaires completed before and after the education programme were analysed. RESULTS: Overall, 95% of the managers (81/85) approved the individualized education format. The characteristic needs of participants with high motivation (45%, 38/85) were mental health consultations for managers (37%, 14/38, 95% confidence interval [CI] 1.62-14.7, P < 0.01) and subordinate-related concerns (18%, 7/38, 95% CI 1.11-22.8, P < 0.05). CONCLUSIONS: Individualized education may be a suitable method for conducting mental health consultations. It is recommended that the introduction of individualized education formats be implemented through voluntary consultations following group education. Individualized education may contribute to early intervention for work-related mental disorders.


Assuntos
Educação em Saúde/métodos , Saúde Mental/educação , Adulto , Feminino , Humanos , Japão , Masculino , Instalações Industriais e de Manufatura/organização & administração , Pessoa de Meia-Idade , Motivação , Saúde Ocupacional , Inquéritos e Questionários , Local de Trabalho
2.
Eur J Gynaecol Oncol ; 38(3): 459-461, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29693892

RESUMO

Lymphoepithelioma-like carcinoma (LELC) is a rare variant of carcinoma of the uterine cervix, of which Epstein-Barr virus (EBV) and/or human papilloma virus (HPV) may play an important role in the pathogenesis. The authors report a case of a patient with cervical LELC who was also examined for the presence of EBV and HPV. A 31-year-old Japanese female presented with irregular genital bleeding. The biopsy showed an invasive squamous cell carcinoma. Based on the clinical data, the patient was diagnosed as having squamous cervical carcinoma, and radical hysterectomy with ovarian conservation was performed. A diagnosis of cervical LELC was then made by histological methods. An additional examination revealed that the patient was infected with HPV types 16 and 71, but not infected with EBV.


Assuntos
Carcinoma/virologia , Papillomaviridae/isolamento & purificação , Neoplasias do Colo do Útero/virologia , Adulto , Carcinoma/diagnóstico , Feminino , Herpesvirus Humano 4/isolamento & purificação , Humanos , Neoplasias do Colo do Útero/diagnóstico
3.
Sarcoidosis Vasc Diffuse Lung Dis ; 30(1): 43-51, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24003534

RESUMO

BACKGROUND: The serum Krebs von der Lungen-6 (KL-6) level is a useful marker correlated with the severity of various interstitial lung diseases. There have been few reports about the clinical characteristics of organizing pneumonia (OP) associated with the serum KL-6 levels. OBJECTIVE: This study was performed to determine whether the serum KL-6 levels can help determine the optimal treatment for OP. DESIGNS: Patients diagnosed with OP by clinical, radiological and histopathological findings were retrospectively reviewed. The OP patients were classified into two groups based on their serum KL-6 levels: normal KL-6 and high KL-6 groups. The two groups were compared with regard to their clinical and radiological data and therapeutic response one month after the start of treatment. RESULTS: The clinical records of twenty-two patients diagnosed with OP were reviewed. The serum KL-6 level was elevated in 11 of the 22 patients. There were no obvious differences in the clinical data between the two groups, although patients in the normal KL-6 group tended to have a fever. There were no significant differences in the chest X-ray (CXR) score or computed tomography (CT) score between the two groups. The CXR scores were correlated with the serum KL-6 levels. At 1 month after the diagnosis, 11 patients who needed treatment with prednisolone were included in the high KL-6 group. CONCLUSIONS: Patients with normal KL-6 levels showed lower CXR and CT scores. The serum KL-6 level on admission is a useful marker to judge the need for corticosteroid treatment in OP patients.


Assuntos
Biomarcadores/sangue , Pneumonia em Organização Criptogênica/sangue , Mucina-1/sangue , Corticosteroides/uso terapêutico , Broncoscopia , Pneumonia em Organização Criptogênica/diagnóstico , Pneumonia em Organização Criptogênica/diagnóstico por imagem , Pneumonia em Organização Criptogênica/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
4.
J Clin Pharm Ther ; 38(1): 12-5, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22882748

RESUMO

WHAT IS KNOWN AND OBJECTIVE: It has been reported that ibuprofen interferes with the antiplatelet effect of low-dose aspirin. This interaction is ascribed to steric hindrance at the active site of cyclooxygenase-1 by ibuprofen, when aspirin is administered after ibuprofen. However, whether other non-steroidal anti-inflammatory drugs (NSAIDs) interact with aspirin similarly is not well defined. The aim of this study was to assess the influence of nine NSAIDs on the antiplatelet effect of aspirin. METHODS: We investigated the antiplatelet effect of NSAIDs using steady-state plasma concentration reported after usual doses. We studied the in vitro antiplatelet effect of NSAID alone, aspirin alone, aspirin before NSAID addition and aspirin after NSAID addition to platelet-rich plasma. The rates of platelet aggregation induced by collagen were determined. The final concentration of aspirin used was the 50% effective concentration (EC(50)) previously estimated in vitro. RESULTS AND DISCUSSION: Ibuprofen and mefenamic acid interfere with the antiplatelet effect of aspirin when added before the latter. The rate of platelet aggregation was reduced by 48·1% and 22·7%, respectively. The other NSAIDs tested did not significantly affect the aspirin antiplatelet effect when exposure was prior to aspirin. None of the nine NSAIDs altered the aspirin effect if administration followed that of aspirin. WHAT IS NEW AND CONCLUSION: Naproxen and flurbiprofen have significant antiplatelet effects at plasma concentrations seen with usual doses. Our in vitro model suggests that the antiplatelet effect of aspirin is significantly diminished when taken after, but not before, ibuprofen or mefenamic acid. None of the other NSAIDs tested had any effect irrespective of the timing of dosing.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Aspirina/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Anti-Inflamatórios não Esteroides/administração & dosagem , Aspirina/administração & dosagem , Colágeno/administração & dosagem , Interações Medicamentosas , Feminino , Humanos , Técnicas In Vitro , Masculino , Fatores de Tempo
5.
Eur J Gynaecol Oncol ; 33(2): 223-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22611970

RESUMO

Malignant mixed Müllerian tumor (MMMT) of the female genital tract is uncommon and extremely rare in the Fallopian tube. We describe a case of primary MMMT of the Fallopian tube with carcinomatous and heterologous mesenchymal components in a 60-year-old woman. The patient underwent total abdominal hysterectomy, bilateral salpingo-oophorectomy, infracolic omentectomy, pelvic and paraaortic lymph node dissection, and resection of intrapelvic metastases. The tumor formed a large polypoid mass within the right Fallopian tube and had penetrated the wall to the paraovarian space. Microscopic examination revealed two components of poorly differentiated adenocarcinoma and high-grade sarcoma with chondromatous differentiation. The patient received six courses of adjuvant chemotherapy with ifomide and cisplatin and is currently in remission. Although MMMT in the Fallopian tube shows poor prognosis, primary cytoreductive surgery with platinum-based combination chemotherapy may improve survival.


Assuntos
Neoplasias das Tubas Uterinas/patologia , Neoplasias das Tubas Uterinas/cirurgia , Tumor Mulleriano Misto/patologia , Tumor Mulleriano Misto/cirurgia , Quimioterapia Adjuvante , Neoplasias das Tubas Uterinas/tratamento farmacológico , Feminino , Humanos , Histerectomia , Excisão de Linfonodo , Pessoa de Meia-Idade , Tumor Mulleriano Misto/tratamento farmacológico , Tumor Mulleriano Misto/secundário , Metástase Neoplásica , Ovariectomia , Salpingectomia
6.
Fetal Diagn Ther ; 24(2): 99-102, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18648207

RESUMO

Meconium peritonitis (MP) is defined as a sterile inflammatory reaction in the fetal abdomen that is seen in cases of intrauterine bowel perforation. Recently, there have been increasing numbers of fetuses with MP prenatally diagnosed by ultrasonography. Massive fetal ascites in MP may cause hydrops and hypoplastic lungs. However, antepartum management of MP has not yet been established. We encountered a fetus with MP and massive ascites. Repeated paracentesis between 29 weeks and 4 days and 31 weeks and 6 days of gestation prevented the progression to fetal hydrops and hypoplastic lungs, which may occur due to massive meconium ascites with an increased preload index. Amniocentesis was also performed in patients with polyhydramnios for treatment of preterm labor. These observations suggest that aggressive therapy can prolong the gestation period and improve MP treatment outcomes.


Assuntos
Ascite/cirurgia , Doenças Fetais/cirurgia , Doenças do Íleo/complicações , Perfuração Intestinal/complicações , Mecônio , Paracentese , Peritonite/cirurgia , Adulto , Ascite/diagnóstico por imagem , Ascite/embriologia , Feminino , Doenças Fetais/diagnóstico por imagem , Idade Gestacional , Humanos , Doenças do Íleo/embriologia , Doenças do Íleo/cirurgia , Lactente , Perfuração Intestinal/embriologia , Perfuração Intestinal/cirurgia , Trabalho de Parto Induzido , Nascido Vivo , Masculino , Peritonite/diagnóstico por imagem , Peritonite/embriologia , Gravidez , Reoperação , Ultrassonografia Doppler em Cores , Ultrassonografia Doppler de Pulso , Ultrassonografia Pré-Natal
7.
Br Poult Sci ; 49(6): 731-5, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19093246

RESUMO

1. The oral administration of glucose or dietary glucose reduces fasting plasma mannose concentrations in mammals. On the other hand, there have been no reports on plasma mannose levels in birds. We have analysed chicken plasma mannose and glucose by an original high-performance liquid chromatography (HPLC) method, together with plasma non-esterified fatty acid (NEFA) concentrations in chickens. 2. Plasma glucose concentrations of chickens did not differ among three different age groups (0, 18 and 150 d). However, the plasma mannose concentrations of chicks at the age of 0 d were higher than those of chickens at the ages of 18 and 150 d. 3. At the age of 18 and 150 d, plasma glucose concentrations were elevated and plasma mannose and NEFA concentrations were decreased after regular feeding, compared to fasting levels.


Assuntos
Glicemia/análise , Galinhas/sangue , Ácidos Graxos não Esterificados/sangue , Manose/sangue , Fatores Etários , Ração Animal , Animais , Galinhas/crescimento & desenvolvimento , Galinhas/metabolismo , Cromatografia Líquida de Alta Pressão , Ingestão de Alimentos , Feminino , Masculino , Fatores de Tempo
8.
Neuroscience ; 141(1): 101-8, 2006 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-16677772

RESUMO

Astrocytes are thought to be critical to neurons' surviving damage caused by ischemic stroke or other injury. Plasminogen activator inhibitor-1 is one of the active soluble factors released by astrocytes and regulates plasminogen activator-plasmin proteolytic sequence in the CNS as a serpin. In this study, we show that plasminogen activator inhibitor-1 can promote neurite outgrowth and survival of rat pheochromocytoma cells in serum-deprived conditions, and that this neuroprotective activity is correlated with enhanced activation of both extracellular signal-regulated kinases following a direct phosphorylation of nerve growth factor receptor, Trk A, and of c-Jun. Our results suggest that plasminogen activator inhibitor-1 can act as a neurotrophic factor, protecting neurons from serum deprivation-induced neuron death not only by compensating for nerve growth factor functions, but also by activating the c-Jun/activating protein-1 pathway.


Assuntos
Diferenciação Celular/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fator de Crescimento Neural/farmacologia , Inibidor 1 de Ativador de Plasminogênio/farmacologia , Proteínas Proto-Oncogênicas c-jun/metabolismo , Inibidores de Serina Proteinase/farmacologia , Animais , Western Blotting/métodos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Interações Medicamentosas , Ativação Enzimática/efeitos dos fármacos , Neuritos/efeitos dos fármacos , Células PC12/citologia , Células PC12/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Ratos , Transdução de Sinais/efeitos dos fármacos
9.
Biochim Biophys Acta ; 877(3): 334-41, 1986 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-3730404

RESUMO

Lignoceroyl-CoA:sphingosine lignoceroyltransferase, which catalyzes synthesis of lignoceroylsphingosine, the ceramide that is a major component of sphingolipids in mammalian tissues, has been solubilized from microsomes of rat brain and liver and partially purified. The microsomes were treated with 1 M sodium thiocyanate in N,N-bis(2-hydroxyethyl)glycine (Bicine) buffer containing 20% glycerol. The supernatant fraction obtained after centrifugation was fractionated by Sepharose CL-4B gel filtration. The ceramide synthetase activity was recovered in a small fraction containing high molecular weight proteins. Analysis of proteins and lipids indicated that the fraction was not simply a fragment of microsomes. The activity for synthesis of lignoceroylsphingosine, which is abundant in nervous system, was compared with that for the synthesis of stearoylsphingosine, which is more enriched in extraneural sphingolipids, in brain and liver microsomes. Despite the difference in relative abundance of molecular species of ceramides in these tissues, the activity for lignoceroylsphingosine synthesis was not more enriched in brain than in liver.


Assuntos
Aciltransferases/isolamento & purificação , Encéfalo/enzimologia , Fígado/enzimologia , Acil Coenzima A/metabolismo , Aciltransferases/análise , Animais , Ceramidas/biossíntese , Cromatografia em Gel , Proteínas/análise , Ratos , Solubilidade , Esfingosina N-Aciltransferase
10.
Biochim Biophys Acta ; 1269(1): 85-90, 1995 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-7578276

RESUMO

Plasminogen activator inhibitor-1 (PAI-1) is a primary endogenous inhibitor of tissue-type plasminogen activator (t-PA). In this study, we examined the effects of oversulfated fucoidan (OSF) derivatives and heparin on lipopolysaccharide (LPS)-induced release of PAI-1 antigen from cultured human umbilical vein endothelial cells (HUVEC). Addition of LPS (10 micrograms/ml) enhanced the release of PAI-1 by HUVEC but not of t-PA antigen. At 18 h, a 2.4-fold increase in the extracellular PAI-1 level was observed. The increased PAI-1 level was reduced to control level by the simultaneous addition of 10 micrograms/ml of OSF or heparin. The suppressive effect of native fucoidan was negligible. We also examined the molecular size effect of OSF, using 10-20, 20-40, and 40-60 kDa fragments. The result indicated that these fragments were effective as well as the 100-130 kDa form of OSF, hence suggesting an important role of the degree of sulfation. Interleukin-1 beta (IL-1 beta) is a potent inducer of PAI-1 in cultured HUVEC. Heparin, OSF, and its fragments did not suppress the IL-1 beta-induced release of PAI-1 antigen. Treatment of HUVEC with heparitinase or monoclonal antibody against heparin sulfate proteoglycan (HSPG) resulted in a complete loss of its ability to enhance PAI-1 release in response to LPS stimulation, while the chondroitinase ABC treatment hardly affected the PAI-1 production. These results suggest that HSPG is involved in the initial binding of LPS to HUVEC. The suppressive effects of OSF and heparin on LPS-induced PAI-1 release may result from the inhibition of LPS binding to the cell surface HSPG.


Assuntos
Anticoagulantes/farmacologia , Heparina/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Inibidor 1 de Ativador de Plasminogênio/biossíntese , Polissacarídeos/farmacologia , Anticorpos Monoclonais/farmacologia , Células Cultivadas , Condroitinases e Condroitina Liases , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Proteoglicanas de Heparan Sulfato , Heparitina Sulfato/imunologia , Heparitina Sulfato/metabolismo , Humanos , Interleucina-1/biossíntese , Peso Molecular , Polissacarídeo-Liases , Polissacarídeos/química , Proteoglicanas/imunologia , Proteoglicanas/metabolismo , Transdução de Sinais
11.
Biochim Biophys Acta ; 999(1): 29-35, 1989 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-2572276

RESUMO

We have previously demonstrated that the heparin-binding site of plasminogen is located in Val442-plasminogen region (kringle 5 domain plus light (B) chain) (Soeda, S., Kakiki, M., Shimeno, H., and Nagamatsu, A. (1987) Biochim. Biophys. Acta 916, 279-287). The chemical modification of Val442-plasminogen with a lysine reagent, pyridoxal 5'-phosphate (PLP), and sodium borohydride resulted in the incorporation of 8-10 PLP moieties per molecule of the zymogen. This PLP-labeled zymogen had no affinity for a heparin-Sepharose column, whereas the non-labeled one bound to the column. Modification in the presence of heparin decreased the extent of labeling by 1-2 mol of PLP per mol of Val442-plasminogen. To further examine the binding site of plasminogen to heparin, functionally active A and B chains were separated from Lys-plasmin after mild reduction and S-carboxymethylation. Only B chain possessed affinity for heparin-Sepharose. Furthermore, plasmin(ogen) bound to heparin was protected from alpha 2-antiplasmin inhibition. These results indicate that one or two lysine residues located in the catalytic region (B chain) of plasmin(ogen) are essential to heparin binding, and that the binding of plasminogen to heparin or heparin-like substance in extracellular matrix environments may be important for the localization and activation of plasminogen and for the prolongation of the resultant plasmin activity.


Assuntos
Heparina/metabolismo , Lisina , Plasminogênio/metabolismo , Sítios de Ligação , Boroidretos , Fenômenos Químicos , Química , Fibrinolisina/metabolismo , Glutamatos/metabolismo , Ácido Glutâmico , Humanos , Fosfato de Piridoxal , Valina
12.
Biochim Biophys Acta ; 916(3): 279-87, 1987 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-3120775

RESUMO

To localize the binding region of porcine tissue-type plasminogen activator (EC 3.4.21.31) (t-plasminogen activator) to heparin, functionally active A and B chains (molecular mass of each 33 kDa) were separated from the two-chain t-plasminogen activator after mild reduction and alkylation. The A chain bound to fibrin-Sepharose, but not to heparin-Sepharose. In contrast, the B chain showed amidase activity toward HD-Ile-Pro-Arg-p-nitroanilide (S-2288) and a high affinity for heparin-Sepharose, but no affinity for fibrin-Sepharose. Plasminogen activator activity of the B chain was stimulated by heparin (about 3-fold), but not by fibrin. On the other hand, the elastase digestion fragments of plasminogen, kringle 1-3 and kringle 4, had no affinity for a heparin-Sepharose column, whereas the other fragment, Val442-plasminogen, efficiently bound to the column and was eluted with 1.6 M KSCN-containing buffer. The stimulatory effect of fibrin on two-chain t-plasminogen activator-catalyzed Val442-plasminogen activation was clearly diminished by heparin. These results suggest that heparin can form a complex with both t-plasminogen activator and plasminogen molecules through their catalytic regions located in each B chain, and that the heparin connection between t-plasminogen activator and plasminogen may improve the plasminogen activation kinetics by making a situation in which t-plasminogen activator is easily approachable to plasminogen.


Assuntos
Heparina/metabolismo , Plasminogênio/metabolismo , Ativador de Plasminogênio Tecidual/metabolismo , Animais , Sítios de Ligação , Cromatografia de Afinidade , Eletroforese em Gel de Poliacrilamida , Fibrina/metabolismo , Oligopeptídeos/metabolismo , Suínos
13.
Biochim Biophys Acta ; 1497(1): 127-34, 2000 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-10838166

RESUMO

We have previously demonstrated that chemically oversulfated fucoidan (OSF) but not native fucoidan (NF) effectively suppresses the tube structure formation by human umbilical vein endothelial cells (HUVEC) on the basement membrane preparation, Matrigel. In this study, using more defined systems where basic fibroblast growth factor (bFGF) induces the tube formation by HUVEC on collagen gel, we investigated the mechanism responsible for the inhibition of angiogenesis by OSF in vitro. Unlike NF and desulfated fucoidan (desF), OSF potently inhibited the bFGF-induced HUVEC migration and tube formation. ELISA for tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) in the culture media indicated that OSF increased the bFGF-induced release of PAI-1 antigen, but not of t-PA antigen. Analyses of the binding of bFGF to HUVEC surfaces and the following protein tyrosine phosphorylation revealed that OSF could promote the cell binding and autophosphorylation of 140 and 160 kDa receptors. In heparitinase-treated HUVEC, contrarily, the bFGF binding and PAI-1 release were decreased by OSF. These results suggest that OSF is a highly sulfated unique polysaccharide that can promote the binding of bFGF to the heparan sulfate molecules required for binding to the high affinity receptors with tyrosine kinase activity. The resultant increase in PAI-1 release may play a key role for the prevention of cell migration accompanied by matrix proteolysis.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Fator 2 de Crescimento de Fibroblastos/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Polissacarídeos/farmacologia , Ligação Competitiva , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Endotélio Vascular/citologia , Endotélio Vascular/fisiologia , Fator 2 de Crescimento de Fibroblastos/metabolismo , Proteoglicanas de Heparan Sulfato/metabolismo , Proteoglicanas de Heparan Sulfato/farmacologia , Humanos , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Polissacarídeos/metabolismo , Sulfatos/metabolismo , Ativador de Plasminogênio Tecidual/efeitos dos fármacos , Ativador de Plasminogênio Tecidual/metabolismo , Veias Umbilicais/citologia
14.
Biochim Biophys Acta ; 1448(1): 37-45, 1998 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-9824663

RESUMO

We have investigated the biochemical mechanism of tumor necrosis factor (TNF)-alpha-induced release of plasminogen activator inhibitor-1 (PAI-1) from human umbilical vein endothelial cells (HUVEC). Treatment of HUVEC with TNF-alpha for 3 h resulted in a 2. 8-fold increase in the PAI-1 release compared with control. The increase in PAI-1 release was accompanied by a 133% increase in the intracellular acidic sphingomyelinase (SMase) activity. High-performance liquid chromatographic (HPLC) analysis revealed that the intracellular ceramide levels increased to 126% of the control (P<0.05), but the contents of membranous ceramide remained unaltered. We have previously shown that a cell-permeable ceramide analog, N-acetylsphingosine (C2-ceramide) enhances the PAI-1 release from HUVEC. Here, N-acetylsphinganine (C2-dihydroceramide) was found to specifically suppress both C2-ceramide- and TNF-alpha-induced increase in PAI-1 release from HUVEC without affecting the control PAI-1 release. Treatment of HUVEC with staphylococcal SMase that may mimic the activation of the membranous neutral SMase also increased the PAI-1 release. The increase in PAI-1 release by this mechanism was suppressed by a cyclooxygenase inhibitor, aspirin, whereas the inhibitor did not affect TNF-alpha-induced increase in PAI-1 release. Taken together, these findings suggest that TNF-alpha prominently utilizes the lysosomal acidic SMase-ceramide signaling pathway in the induction of PAI-1 release from HUVEC.


Assuntos
Ceramidas/metabolismo , Endotélio Vascular/metabolismo , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Ceramidas/farmacologia , Fragmentação do DNA , Endossomos/metabolismo , Endotélio Vascular/efeitos dos fármacos , Humanos , Lisossomos/metabolismo , Transdução de Sinais , Esfingomielina Fosfodiesterase/metabolismo , Esfingosina/análogos & derivados , Esfingosina/farmacologia , Veias Umbilicais/citologia
15.
Biochim Biophys Acta ; 1037(3): 302-6, 1990 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-2178686

RESUMO

Coenzyme A (CoA), its related compounds and acylcarnitine non-competitively inhibited the activity of proline endopeptidase (PEPase) purified from rat liver cytosol. The degree of inhibition was in the order of acyl-CoA greater than CoA greater than dephospho-CoA greater than or equal to acylcarnitine. However, carnitine did not inhibit the enzyme activity. Among the compounds examined, n-decanoyl-CoA showed the highest inhibitory activity (Ki = 9 microM). These results suggest that both the acyl group and CoA contribute to the inhibition of PEPase by acyl-CoA. The abilities of n-decanoyl-CoA and its related compounds to quench the intrinsic fluorescence at 332 nm from PEPase excited at 280 nm, was used as a probe for the binding affinity of the enzyme for these compounds. The quenching of fluorescence by CoA was nearly equal to that by n-decanoyl-CoA. n-Decanoylcarnitine and carnitine were unable to quench the fluorescence. These results indicate that n-decanoyl-CoA at least binds to PEPase through its CoA portion.


Assuntos
Acil Coenzima A/farmacologia , Ácidos Carboxílicos/farmacologia , Endopeptidases/metabolismo , Ésteres/farmacologia , Fígado/enzimologia , Serina Endopeptidases , Animais , Carnitina/farmacologia , Coenzima A/farmacologia , Citosol/enzimologia , Cinética , Prolil Oligopeptidases , Ratos , Espectrometria de Fluorescência , Relação Estrutura-Atividade
16.
Biochim Biophys Acta ; 1199(3): 279-84, 1994 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-8161566

RESUMO

We have previously shown that the naturally occurring polyamines, spermidine and spermine, reverse effectively the in vitro inhibition of prolyl oligopeptidase (POPase) by its endogenous inhibitor by forming a kinetically significant complex (Soeda et al., J. Neurochem. (1986) 46, 1304-1307). In this study, we examined changes in the activities of POPase and its endogenous inhibitor and in the concentrations of polyamines during the regeneration of rat liver. POPase activity in the liver cytosol peaked 2 days after partial hepatectomy and then decreased near to control activity by 9 days, without its altered synthetic levels. Total polyamine concentrations also peaked at 2 days and remained elevated by 9 days, while cytosolic POPase inhibitor activity was minimal (56% of control) at 2 days. Treatment of the animals with a synthetic POPase inhibitor, Z-Gly-Pro-CHN2 (4 mg/kg), resulted in an obvious suppression of the liver regeneration. These results imply that the activity of POPase involved in nonlysosomal proteolytic pathway is exquisitely regulated by changes not only in its endogenous inhibitor levels but also in intracellular cationic potentials such as polyamines, and that POPase plays a crucial role for the growth and differentiation of liver cell.


Assuntos
Regeneração Hepática , Fígado/enzimologia , Serina Endopeptidases/fisiologia , Sequência de Aminoácidos , Animais , Diazometano/análogos & derivados , Diazometano/farmacologia , Fígado/ultraestrutura , Masculino , Dados de Sequência Molecular , Poliaminas/farmacologia , Prolil Oligopeptidases , Ratos , Ratos Wistar , Inibidores de Serina Proteinase/farmacologia
17.
Biochim Biophys Acta ; 1538(2-3): 234-41, 2001 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-11336794

RESUMO

The anthracycline antibiotic daunorubicin is reported to induce apoptosis in cells by triggering ceramide generation through de novo synthesis or sphingomyelin hydrolysis. Treatment of human umbilical vein endothelial cells (HUVEC) with daunorubicin markedly decreased the mRNA expression and protein release of plasminogen activator inhibitor-1 (PAI-1). This cellular event was accompanied by a significant increase in the total ceramide content in HUVEC. On the other hand, tumor necrosis factor (TNF)-alpha treatment of HUVEC led to an increase in both PAI-1 mRNA expression and protein release, and an enhancement of total ceramide content was also observed. The stimulating effect of TNF-alpha on PAI-1 synthesis was attenuated by the pretreatment of HUVEC with daunorubicin. Interestingly, the daunorubicin-induced increase in ceramide content was blocked by addition of the potent ceramide synthase inhibitor fumonisin B(1), while the TNF-alpha-induced ceramide increase was not affected by this drug. Fumonisin B(1) treatment restored the daunorubicin-induced decrease in PAI-1 release to approximately 70% of the control, but did not affect the TNF-alpha-induced increase in PAI-1 release. Thus, these data imply the possibility that the subcellular topology of ceramide production determines its lipid mediator function in the regulation of PAI-1 synthesis in HUVEC, because both TNF-alpha and daunorubicin could increase the ceramide levels.


Assuntos
Daunorrubicina/farmacologia , Endotélio Vascular/efeitos dos fármacos , Fumonisinas , Inibidor 1 de Ativador de Plasminogênio/biossíntese , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Ácidos Carboxílicos/farmacologia , Células Cultivadas , Ceramidas/metabolismo , Endotélio Vascular/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Inibidor 1 de Ativador de Plasminogênio/genética , RNA Mensageiro/análise , RNA Mensageiro/biossíntese , Esfingomielinas/metabolismo , Veias Umbilicais/efeitos dos fármacos , Veias Umbilicais/metabolismo
18.
Biochim Biophys Acta ; 836(1): 80-8, 1985 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-3161545

RESUMO

As part of a long-term study of sphingolipid metabolism in brain, we have purified and partially characterized a long-chain acyl-CoA synthetase from microsomes of developing rat brain and compared it with the hepatic microsomal enzyme from the same animals. Both enzymes were solubilized from microsomes by treatment with Triton X-100 and then chromatographed successively on Blue-Sepharose and DEAE-Sepharose. Blue-Sepharose chromatography yielded a single peak with acyl-CoA synthetase activity, whereas DEAE-Sepharose chromatography of both brain and liver preparations yielded two peaks. Elution patterns of lignoceroyl-CoA synthetase and palmitoyl-CoA synthetase activities were identical throughout these steps and were similar in brain and liver. Gel filtration of each DEAE-Sepharose fraction on Sephadex G-200 also yielded two peaks of activity. The more rapidly eluted material contained much more lignoceroyl-CoA synthetase activity, while the activity for palmitoyl-CoA synthetase was higher in slower eluting peaks. In all preparations the ratio of lignoceroyl-CoA synthetase activity to palmitoyl-CoA synthetase activity was much higher in brain than in liver. These results suggest that although the brain acyl-CoA synthetase is chromatographically similar to the liver enzyme, there are differences in substrate specificity.


Assuntos
Encéfalo/enzimologia , Coenzima A Ligases/metabolismo , Microssomos Hepáticos/enzimologia , Proteínas Repressoras , Proteínas de Saccharomyces cerevisiae , Animais , Encéfalo/ultraestrutura , Cromatografia em Gel , Cromatografia por Troca Iônica , Cromatografia em Camada Fina , Microssomos/enzimologia , Octoxinol , Polietilenoglicóis/farmacologia , Ratos , Ratos Endogâmicos , Solubilidade
19.
Cancer Lett ; 108(1): 49-54, 1996 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-8950208

RESUMO

We constructed vascular endothelial cell monolayer on a fibronectin-coated filter in a Boyden chamber and assessed the ability of 3 LL cells to penetrate through the artificial blood vessel wall. The defense of endothelial cell monolayers against the tumor cell invasion was greatly potentiated by their pretreatment with 5 or 10 micrograms/ml of brefeldin A (BFA) for 1 h (52% or 28% of control invasion). Treatment of the endothelial cell monolayers with BFA resulted in an increase in the release of inhibitory material(s) against urokinase-type plasminogen activator (u-PA) activity of 3 LL cells. Parallel experiments with the cultured endothelial cells and BFA indicated that the fungal metabolite enhanced a rate of accumulation of plasminogen activator inhibitor-1 (PAI-1) antigen, but not of tissue-type plasminogen activator antigen in the medium. The BFA-induced enhancement of PAI-1 antigen release was accompanied with the increased accumulation of the extracellular (membrane/matrix-bound) and intracellular PAI-1 antigen (219% of control at 24 h). These results suggest that BFA can strengthen the defense of vascular endothelium against tumor-cell invasion by enhancing the release and accumulation of PAI-1, which plays a critical role in the regulation of the u-PA-plasmin-collagenase activation cascade.


Assuntos
Ciclopentanos/farmacologia , Endotélio Vascular/efeitos dos fármacos , Invasividade Neoplásica/prevenção & controle , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Brefeldina A , Adesão Celular/efeitos dos fármacos , Células Cultivadas , Colagenases/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Matriz Extracelular/metabolismo , Humanos , Ativador de Plasminogênio Tecidual/metabolismo , Células Tumorais Cultivadas , Veias Umbilicais
20.
Cancer Lett ; 85(1): 133-8, 1994 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-7923097

RESUMO

Fucoidan is reported to have an antimetastatic activity. In the present study, we prepared an amino group-introduced derivative of fucoidan and examined its effect on the invasion of 3 LL cells through a reconstituted basement membrane (MatrigelTM). Unlike native fucoidan, the aminated derivative promoted the tumor cell invasion: maximal promotion (240% of control invasion) was obtained with 5 micrograms/ml. However, with higher concentrations (10-30 micrograms/ml) of the fucoidan derivative, the promotion was gradually reduced to 130% of control. Both native and aminated fucoidans inhibited specifically the attachment of 3 LL cells to laminin. Interestingly, aminated fucoidan, unlike the native one, promoted the tumor cell adhesion to immobilized synthetic laminin B 1 chain peptide, YIGSR, over a concentration range of 0.5-5 micrograms/ml. Higher concentrations (7-20 micrograms/ml) of the aminated derivative suppressed the adhesive ability of 3 LL cells to YIGSR. 3 LL cells secreted a 50-kDa form of urokinase-type plasminogen activator (u-PA) in the culture medium. Addition of aminated fucoidan (5 micrograms/ml) or YIGSR (10 micrograms/ml) resulted in a 1.7-fold increase in u-PA activity. This effect was enhanced up to 3.5-fold when both substances were simultaneously added. The addition of native fucoidan had no effect. The present results suggest that the 67-kDa receptor-mediated binding of 3 LL cells to laminin activates their invasiveness, especially by enhancing the extracellular u-PA levels. Aminated, but not native, fucoidan may act to enhance the laminin-receptor interaction at the limited concentration range.


Assuntos
Anticoagulantes/toxicidade , Carcinoma Pulmonar de Lewis/patologia , Carcinoma Pulmonar de Lewis/ultraestrutura , Polissacarídeos/toxicidade , Aminação , Sequência de Aminoácidos , Animais , Membrana Basal/efeitos dos fármacos , Membrana Basal/fisiologia , Carcinoma Pulmonar de Lewis/metabolismo , Colágeno/metabolismo , Fibronectinas/metabolismo , Laminina/metabolismo , Dados de Sequência Molecular , Invasividade Neoplásica , Polissacarídeos/metabolismo , Receptores de Laminina/fisiologia , Células Tumorais Cultivadas/efeitos dos fármacos , Ativador de Plasminogênio Tipo Uroquinase/metabolismo
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