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1.
Geophys J Int ; 229(3): 1914-1926, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35250356

RESUMO

Here we qualitatively analyse the mass change patterns across Antarctica via independent component analysis (ICA), a statistics-based blind source separation method to extract signals from complex data sets, in an attempt to reduce uncertainties in the glacial isostatic adjustment (GIA) effects and improve understanding of Antarctic Ice Sheet (AIS) mass-balance. We extract the six leading independent components from gravimetric data acquired during the Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On (GRACE-FO) missions. The results reveal that the observed continental-scale mass changes can be effectively separated into several spatial patterns that may be dominated by different physical processes. Although the hidden independent physical processes cannot be completely isolated, some significant signals, such as glacier melt, snow accumulation, periodic climatic signals, and GIA effects, can be determined without introducing any external information. We also observe that the time period of the analysed data set has a direct impact on the ICA results, as the impacts of extreme events, such as the anomalously large snowfall events in the late 2000s, may cause dramatic spatial and temporal changes in the ICA results. ICA provides a unique and informative approach to obtain a better understanding of both AIS-scale mass changes and specific regional-scale spatiotemporal signal variations.

2.
Sci Total Environ ; 407(9): 3153-64, 2009 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18790519

RESUMO

Anthropogenic effects in both Osaka and Bangkok were evaluated to compare the relationships between subsurface environment and the development stage of both cities. Subsurface thermal anomalies due to heat island effects were found in both cities. The Surface Warming Index (SWI), the departure depth from the steady geothermal gradient, was used as an indicator of the heat island effect. SWI increases (deeper) with the magnitude of heat island effect and the elapsed time starting from the surface warming. Distributions of subsurface thermal anomalies due to the heat island effect agreed well with the distribution of changes in air temperature due to the same process, which is described by the distribution of population density in both Osaka and Bangkok. Different time lags between groundwater depression and subsidence in the two cities was found. This is attributed to differences in hydrogeologic characters, such as porosity and hydraulic conductivity. We find that differences in subsurface degradations in Osaka and Bangkok, including subsurface thermal anomalies, groundwater depression, and land subsidence, depends on the difference of the development stage of urbanization and hydrogeological characters.


Assuntos
Meio Ambiente , Monitoramento Ambiental/métodos , Poluição Ambiental/efeitos adversos , Efeito Estufa , Urbanização/tendências , Ásia , Cidades , Água Doce , Fenômenos Geológicos , Humanos , Abastecimento de Água
3.
Sci Total Environ ; 407(9): 3173-80, 2009 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18593639

RESUMO

In order to establish a new technique for monitoring groundwater variations in urban areas, the applicability of precise in-situ gravity measurements and extremely high precision satellite gravity data via GRACE (Gravity Recovery and Climate Experiment) was tested. Using the GRACE data, regional scale water mass variations in four major river basins of the Indochina Peninsula were estimated. The estimated variations were compared with Soil-Vegetation-Atmosphere Transfer Scheme (SVATS) models with a river flow model of 1) globally uniform river velocity, 2) river velocity tuned by each river basin, 3) globally uniform river velocity considering groundwater storage, and 4) river velocity tuned by each river basin considering groundwater storage. Model 3) attained the best fit to the GRACE data, and the model 4) yielded almost the same values. This implies that the groundwater plays an important role in estimating the variation of total terrestrial storage. It also indicates that tuning river velocity, which is based on the in-situ measurements, needs further investigations in combination with the GRACE data. The relationships among GRACE data, SVATS models, and in-situ measurements were also discussed briefly.


Assuntos
Monitoramento Ambiental/métodos , Gravitação , Astronave/instrumentação , Poluição Química da Água/análise , Japão , Modelos Teóricos , Rios , Abastecimento de Água
4.
J Periodontal Res ; 40(6): 461-8, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16302924

RESUMO

BACKGROUND: Human bikunin, a Kunitz-type trypsin inhibitor, inhibits inflammation by down-regulating the expression of proinflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha) in tumor cells and inflammatory cells. OBJECTIVES: We analyzed the effect of a soybean-derived Kunitz trypsin inhibitor (KTI) on TNF-alpha production in human gingival fibroblasts stimulated by lipopolysaccharide (LPS), an inflammatory inducer. MATERIAL AND METHODS: Mitogen-activated protein kinase (MAPK) activation and cytokine levels were monitored using western blot and a specific enzyme-linked immunosorbent assay (ELISA). RESULTS: Here, we show (i) a soybean KTI abrogates LPS-induced up-regulation of TNF-alpha mRNA and protein expression in a dose-dependent manner in gingival fibroblasts, (ii) KTI also blocks the induction of TNF-alpha target molecules interleukin-1beta (IL-1beta) and IL-6 proteins, (iii) inhibition by KTI of TNF-alpha induction correlates with the suppressive capacity of extracellular signal-regulated kinase 1/2 (ERK1/2) and p38 signaling pathways, implicating repressed ERK1/2 and p38 signalings in the inhibition, and (iv) pretreatment of cells with KTI blocked LPS-induced nuclear factor kappaB (NFkappaB) activation. CONCLUSION: Our results indicate that KTI inhibits LPS-induced up-regulation of cytokine expression possibly through suppression of ERK1/2 and p38 kinase-mediated NFkappaB activation. These findings may identify anti-inflammatory properties of KTI at the level of gingival fibroblasts and may be relevant to the use of KTI in modulating inflammation, including periodontal disease.


Assuntos
Fibroblastos/efeitos dos fármacos , Gengiva/efeitos dos fármacos , Mediadores da Inflamação/farmacologia , Lipopolissacarídeos/farmacologia , Inibidor da Tripsina de Soja de Kunitz/farmacologia , Inibidores da Tripsina/farmacologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adulto , Células Cultivadas , Regulação para Baixo , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Feminino , Gengiva/citologia , Humanos , Interleucina-1/antagonistas & inibidores , Interleucina-6/antagonistas & inibidores , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Regulação para Cima/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores
5.
Exp Dermatol ; 14(10): 765-74, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16176285

RESUMO

BACKGROUND: Cytokines are produced as a consequence of photo-damaged DNA and oxidative stress in ultraviolet (UV)-exposed keratinocytes. A soybean Kunitz trypsin inhibitor (KTI) down-regulates the expression of proinflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha) in tumor cells and inflammatory cells. AIM: The effect of KTI on TNF-alpha production in UV-exposed primary human keratinocytes was analyzed. RESULTS: We show (i) UV induced up-regulation of TNF-alpha mRNA and protein expression in keratinocytes; (ii) cells treated with KTI before UV irradiation showed a significantly lower accumulation of TNF-alpha protein in a dose-dependent manner and a reduced UV-induced up-regulation of TNF-alpha mRNA expression; (iii) KTI inhibited the induction of TNF-alpha target molecules interleukin-1beta (IL-1beta) and IL-6 proteins; (iv) UV irradiation transiently activated c-Jun N-terminal kinase (JNK) and Akt signaling but only weakly activated extracellular signal-regulated kinase (ERK) and p38; (v) KTI specifically inhibited UV-induced activation of ERK, JNK, and p38, but not Akt; (vi) treatment of cells with SP600125, a pharmacological inhibitor of JNK, predominantly suppressed UV-induced up-regulation of TNF-alpha expression; and (vii) KTI did not enhance suppression of UV-induced JNK phosphorylation by SP600125. CONCLUSIONS: KTI specifically inhibited UV-induced up-regulation of cytokine expression predominantly through suppression of JNK signaling pathway.


Assuntos
Queratinócitos/efeitos da radiação , Inibidor da Tripsina de Soja de Kunitz/farmacologia , Fator de Necrose Tumoral alfa/genética , Raios Ultravioleta , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Queratinócitos/fisiologia , L-Lactato Desidrogenase/análise , Quinases de Proteína Quinase Ativadas por Mitógeno/efeitos dos fármacos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Necrose Tumoral alfa/metabolismo
6.
J Biol Chem ; 280(36): 31428-37, 2005 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-16002410

RESUMO

A soybean Kunitz trypsin inhibitor (KTI) interacts with cells as a negative modulator of the invasive cells. Using complementary pharmacological and genetic approaches, we provide novel findings regarding mechanisms by which KTI inhibits signaling pathways in ovarian cancer cells leading to invasion. Transforming growth factor-beta1 (TGF-beta1) directly activates Src kinase, which in turn activates ERK-phosphatidylinositol 3-kinase/Akt, the downstream targets of Src, for urokinase-type plasminogen activator (uPA) up-regulation in human ovarian cancer HRA cells. Preincubation of the HRA cells with KTI reduced the ability of TGF-beta1 to trigger the uPA expression at the gene level and at the protein level. To further elucidate the mechanism of the KTI-dependent suppressive effect of TGF-beta1-induced uPA expression and invasion, we investigated which signaling pathway transduced by KTI is responsible for this inhibitory effect. Here, we show that 1) KTI suppressed TGF-beta1-induced phosphorylation of Src, ERK1/2, and Akt by 40-60%; 2) KTI was insensitive to suppress the phosphorylation of ERK1/2 and Akt in the constitutively active (CA)-c-Src (Y529F) cells; 3) uPA expression was up-regulated in TGF-beta1-stimulated HRA cells and in unstimulated Y529F cells; 4) the addition of KTI reduced the TGF-beta1-induced increase of uPA gene and protein expression in the wild-type c-Src-transfected cells (in contrast, KTI could not inhibit uPA expression in the Y529F cells); and 5) CA-c-Src transfection resulted in a 2-fold increase in invasiveness, whereas KTI did not reduce invasion of the Y529F cells. Using additional complementary genetic approaches (CA-MEK1, CA-Akt, or kinase-dead-Akt), we conclude that KTI may suppress uPA expression and promotion of invasion possibly through one or more upstream targets of Src.


Assuntos
Glycine max/enzimologia , Transdução de Sinais/fisiologia , Inibidor da Tripsina de Soja de Kunitz/farmacologia , Ativador de Plasminogênio Tipo Uroquinase/antagonistas & inibidores , Ativador de Plasminogênio Tipo Uroquinase/fisiologia , Quinases da Família src/antagonistas & inibidores , Quinases da Família src/fisiologia , Linhagem Celular Tumoral , Repressão Enzimática/efeitos dos fármacos , Repressão Enzimática/fisiologia , Feminino , Humanos , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosfatidilinositol 3-Quinases/fisiologia , Inibidores de Fosfoinositídeo-3 Quinase , Fosforilação , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Glycine max/genética , Fator de Crescimento Transformador beta/antagonistas & inibidores , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta1 , Regulação para Cima , Ativador de Plasminogênio Tipo Uroquinase/biossíntese
7.
J Cancer Res Clin Oncol ; 131(8): 527-38, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15883813

RESUMO

PURPOSE: The Basidiomycete fungus Agaricus blazei Murill has traditionally been used as a health food for the prevention of cancer. METHODS: We examined whether beta-(1-6)-D: -glucan extracted from A. blazei is a potential anticancer agent in an in vitro and in vivo animal model. RESULTS: Here we show that (1) beta-glucan had cytotoxic effect against human ovarian cancer HRA cells, but not against murine Lewis lung cancer 3LL cells, in vitro; (2) beta-glucan promotes p38 MAPK activity for suppressing HRA cell proliferation and amplifying the apoptosis cascade; (3) beta-glucan stimulates translocation of the proapoptotic protein, Bax, from the cytosol to mitochondria, cytochrome c release, and subsequent caspase-9 activation; (4) treatment with SB203580, a p38 MAPK-specific inhibitor, suppresses beta-glucan-induced effects, indicating that activation of p38 MAPK is involved in the suppression of cell proliferation and mitochondrial activation-mediated cell death pathway; (5) in mice, oral supplementation with beta-glucan reduces pulmonary metastasis of 3LL cells and peritoneal disseminated metastasis of HRA cells and inhibits the growth of these metastatic tumors in lung or peritoneal cavity, in part, by suppressing uPA expression; and (6) in an in vivo experimental metastasis assay, however, the oral supplementation with beta-glucan after i.v. tumor cell inoculation did not reduce the number of lung tumor colonies. CONCLUSION: Treatment with beta-glucan may be beneficial for cancer patients with or at risk for metastasis. The beta-glucan-dependent signaling pathways are critical for our understanding of anticancer events and development of cancer therapeutic agents.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Peritoneais/tratamento farmacológico , beta-Glucanas/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Administração Oral , Agaricus , Animais , Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Lewis/prevenção & controle , Proliferação de Células/efeitos dos fármacos , Esquema de Medicação , Ativação Enzimática/efeitos dos fármacos , Feminino , Humanos , Camundongos , Neoplasias Ovarianas/patologia , Neoplasias Peritoneais/secundário , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas , beta-Glucanas/administração & dosagem
8.
Shock ; 23(5): 441-7, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15834310

RESUMO

We examined the modifying effects of a Kunitz trypsin inhibitor (KTI) and a Bowman-Birk trypsin inhibitor (BBI), purified from soybean, as intraperitoneal (i.p.) injection and dietary supplements on bacterial lipopolysaccharide (LPS)-induced lethality in mice. We initially examined the suppressing effects of i.p. injection of KTI (50 mg/kg) and BBI (50 mg/kg) on LPS-induced lethality after i.p. injection of LPS. Furthermore, groups of female C57BL/6 were fed a basal diet (control group) or the basal diet supplemented with KTI (50 g/kg) or BBI (50 g/kg). Here, we show that i.p. and daily oral administration of KTI, but not BBI, caused a significant reduction of the LPS-induced lethality; that LPS significantly induced plasma TNF-alpha, IL-1beta, and IL-6 levels in mice after LPS challenge; that concomitant administration of KTI, but not BBI, inhibits the LPS-induced plasma levels of these cytokines; and that KTI, but not BBI, suppressed LPS-induced upregulation of cytokine expression through suppression of phosphorylation of three mitogen-activated protein (MAP) kinase pathways, ERK1/2, JNK, and p38, in peritoneal macrophages. These data allow us to speculate that i.p. injection and dietary supplementation of a soybean KTI may play a role as a potent anti-inflammatory agent by inhibiting activation of MAP kinases, leading to the suppression of cytokine expression.


Assuntos
Suplementos Nutricionais , Lipopolissacarídeos/farmacologia , Inibidor da Tripsina de Soja de Kunitz/farmacologia , Administração Oral , Animais , Anti-Inflamatórios/farmacologia , Western Blotting , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Ativação Enzimática , Feminino , Inflamação , Interleucina-1/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos/metabolismo , Sistema de Sinalização das MAP Quinases , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Transdução de Sinais , Glycine max/metabolismo , Fatores de Tempo , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
9.
Int J Cancer ; 112(3): 519-24, 2004 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-15382080

RESUMO

The modifying effects of a Kunitz trypsin inhibitor (KTI) and a Bowman-Birk trypsin inhibitor (BBI), purified from soybean trypsin inhibitor, as dietary supplements on experimental and spontaneous pulmonary metastasis of murine Lewis lung carcinoma 3LL cells as well as peritoneal disseminated metastasis model in human ovarian cancer HRA cells were investigated in i.v., s.c. and i.p. injection models in mice. Seven groups of female C57BL/6 or nude mice were fed a basal diet (control group) or the basal diet supplemented with KTI or BBI (5, 15, or 50 g/kg). Here we show that, in an in vivo spontaneous metastasis assay, the diet supplementation with KTI (15 and 50 g/kg), but not with BBI, for 28 days immediately after s.c. tumor cell inoculation significantly inhibited the formation of lung metastasis in C57BL/6 mice in a dose-dependent manner. The inhibition of lung metastasis was not due to direct antitumor effects of KTI. In an in vivo experimental metastasis assay, the diet supplementation with KTI or BBI for 21 days after i.v. tumor cell inoculation did not reduce the number of lung tumor colonies. In addition, KTI (15 or 50 g/kg) treatment in a peritoneal disseminated metastasis model of HRA cells resulted in a 40% reduction in total tumor burden when compared with control animals. Immunoblot analysis revealed that KTI specifically reduced expression of uPA protein as well as phosphorylation of MAP kinase and PI3 kinase proteins in the cells stimulated with agonists (G-CSF for 3LL cells or TGF-beta1 for HRA cells). These results suggest that dietary supplementation of KTI more efficiently regulates the mechanism involved in the entry into vascular circulation of tumor cells (intravasation) than in extravasation during the metastatic process. KTI treatment may also be beneficial for ovarian cancer patients with or at risk for peritoneal disseminated metastasis; it greatly reduces tumor burden in part by inhibiting phosphorylation of MAP kinase and PI3 kinase, leading to suppression of uPA expression.


Assuntos
Carcinoma Pulmonar de Lewis/patologia , Neoplasias Pulmonares/secundário , Modelos Animais , Neoplasias Ovarianas/patologia , Inibidor da Tripsina de Soja de Bowman-Birk/farmacologia , Inibidor da Tripsina de Soja de Kunitz/farmacologia , Inibidores da Tripsina/farmacologia , Animais , Carcinoma Pulmonar de Lewis/metabolismo , Linhagem Celular Tumoral/efeitos dos fármacos , Suplementos Nutricionais , Inibidores Enzimáticos/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos/farmacologia , Humanos , Neoplasias Pulmonares/prevenção & controle , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Ovarianas/metabolismo , Neoplasias Peritoneais/prevenção & controle , Neoplasias Peritoneais/secundário , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Fator de Crescimento Transformador beta/farmacologia , Fator de Crescimento Transformador beta1 , Ativador de Plasminogênio Tipo Uroquinase/metabolismo
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