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1.
Rev Sci Instrum ; 94(3): 033511, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37012804

RESUMO

High-power, short-pulse laser-driven fast electrons can rapidly heat and ionize a high-density target before it hydrodynamically expands. The transport of such electrons within a solid target has been studied using two-dimensional (2D) imaging of electron-induced Kα radiation. However, it is currently limited to no or picosecond scale temporal resolutions. Here, we demonstrate femtosecond time-resolved 2D imaging of fast electron transport in a solid copper foil using the SACLA x-ray free electron laser (XFEL). An unfocused collimated x-ray beam produced transmission images with sub-micron and ∼10 fs resolutions. The XFEL beam, tuned to its photon energy slightly above the Cu K-edge, enabled 2D imaging of transmission changes induced by electron isochoric heating. Time-resolved measurements obtained by varying the time delay between the x-ray probe and the optical laser show that the signature of the electron-heated region expands at ∼25% of the speed of light in a picosecond duration. Time-integrated Cu Kα images support the electron energy and propagation distance observed with the transmission imaging. The x-ray near-edge transmission imaging with a tunable XFEL beam could be broadly applicable for imaging isochorically heated targets by laser-driven relativistic electrons, energetic protons, or an intense x-ray beam.

2.
Clin Exp Allergy ; 42(5): 738-46, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22092552

RESUMO

BACKGROUND: Asthma is a clinical syndrome characterized by variabilities in disease expression and severity. The pathophysiological mechanism underlying anti-asthma treatment resistance is also assumed to be different between disease phenotypes. OBJECTIVE: To elucidate the effect of gender and atopic phenotype on the relationship between clinical factors and the risk of treatment resistance. METHODS: We compared outpatients with difficult-to-treat asthma (DTA; n = 486) in a tertiary hospital for allergic diseases in central Japan with those with controlled severe asthma (n = 621) with respect to clinical factors including body mass index (BMI) and aspirin intolerance using multivariate logistic regression analysis stratified by gender and atopic phenotype. RESULTS: When analysis was performed on the entire study populations, obesity (BMI ≥ 30 kg/m(2); adjusted odds ratio (OR) 1.92; 95% confidence interval (95% CI: 1.07-3.43) and aspirin intolerance (OR: 2.56, 95% CI: 1.44-4.57) were found to be the significant risk factors for DTA. However, after the stratification by gender and atopic phenotype, the association between obesity and DTA was significant only in women (OR: 2.76, 95% CI: 1.31-5.78), but not in men (OR: 1.03, 95% CI: 0.38-2.81), and only in non-atopics (OR: 4.03, 95% CI: 1.15-14.08), but not in atopics (OR: 1.54, 95% CI: 0.79-3.02). The similar gender and phenotypic differences were also observed in the association between aspirin intolerance and DTA: namely, the association was significant only in women (OR: 3.96, 95% CI: 1.84-8.50), but not in men (OR: 1.19, 95% CI: 0.46-3.05); and only in non-atopics (OR: 5.49, 95% CI: 1.98-15.19), but not in atopics (OR: 1.39, 95% CI: 0.65-2.98). CONCLUSIONS AND CLINICAL RELEVANCE: Significant associations of obesity and aspirin intolerance with DTA were observed only in women and in non-atopics. These findings suggest that a phenotype-specific approach is needed to treat patients with DTA.


Assuntos
Povo Asiático , Aspirina/efeitos adversos , Asma/complicações , Hipersensibilidade a Drogas/complicações , Obesidade/complicações , Adulto , Idoso , Asma/terapia , Índice de Massa Corporal , Feminino , Humanos , Hipersensibilidade Imediata/complicações , Japão , Masculino , Pessoa de Meia-Idade , Fenótipo , Fatores de Risco , Fatores Sexuais
3.
Clin Exp Allergy ; 41(12): 1711-8, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22093074

RESUMO

BACKGROUND: Although an abnormality in arachidonic acid metabolism may be responsible for aspirin-intolerant asthma (AIA), there is little knowledge about the concentrations of urinary lipoxin A(4) (LXA(4)) and the 15-epimer of LXA(4) (15-epi-LXA(4)) in relation to asthma severity in AIA subjects. OBJECTIVE: The purpose of this study is to estimate urinary LXA(4) and the 15-epimer concentrations to investigate lipoxins in AIA. METHODS: In this study, we examined AIA, aspirin-tolerant asthma (ATA) and healthy control groups. The AIA and ATA groups were subdivided into the severe asthma and non-severe asthma subgroups. Urinary LXA(4), 15-epi-LXA(4) and leukotriene E(4) (LTE(4) ) were quantified using enzyme immunoassay after separating these compounds using high-performance liquid chromatography. RESULTS: The urinary LXA(4) concentration was significantly lower than the 15-epi-LXA(4) concentration in the asthmatic subjects. The AIA group showed significantly lower urinary 15-epi-LXA(4) (P < 0.01) and higher urinary LTE(4) concentrations (P < 0.05) than the ATA group. Comparison of 15-epi-LXA(4) concentrations between the severe asthmatic and non-severe asthmatic subjects in the AIA and ATA groups revealed that the decreased 15-epi-LXA(4) concentration may be related to aspirin intolerance, but not asthma severity. Receiver operator characteristic curves demonstrated that the concentration ratio of LTE(4) to 15-epi-LXA(4) was superior to 15-epi-LXA(4) concentration and LTE(4) concentration as a predictive factor for aspirin intolerance. CONCLUSIONS AND CLINICAL RELEVANCE: We have demonstrated for the first time that urinary 15-epi-LXA(4) concentration is significantly higher than LXA(4) concentration in both the AIA and ATA groups. 15-Epi-LXA(4) concentration was significantly lower in the AIA group with an increased urinary LTE(4) concentration than in the ATA group. An imbalance between proinflammatory cysteinyl-leukotrienes and anti-inflammatory 15-epi-LXA(4) may be involved in AIA pathogenesis.


Assuntos
Asma Induzida por Aspirina/urina , Lipoxinas/urina , Adulto , Idoso , Aspirina/efeitos adversos , Asma Induzida por Aspirina/etiologia , Feminino , Humanos , Leucotrieno E4/urina , Masculino , Pessoa de Meia-Idade , Curva ROC
4.
Clin Exp Allergy ; 39(1): 72-80, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19128354

RESUMO

BACKGROUND: Anaphylaxis is a life-threatening syndrome resulting from the sudden release of mast cell- and basophil-derived mediators into the circulation. However, pathological evidence of the association between inflammatory mediators and human anaphylaxis is insufficient. OBJECTIVE: The aim of this study was to better understand the relationship between in vivo production of inflammatory mediators and the pathogenesis of anaphylaxis. We also sought to evaluate mast cell activation in anaphylaxis. METHODS: We measured the concentrations of various inflammatory mediators in urine samples, which were collected from 32 anaphylactic patients during the onset of anaphylaxis and during clinical remission, 21 patients with asthma on acute exacerbation and 15 healthy control subjects. Blood and urine specimens were collected from the patients after provocation test. Urinary leukotriene E4 (LTE4), 9alpha, 11beta-prostaglandin F2 (9alpha, 11beta-PGF2), eosinophil-derived neurotoxin (EDN) and leukotriene B4 glucuronide (LTBG) concentrations were determined by enzyme immunoassay, and the activity of plasma platelet-activating factor acetylhydrolase and serum tryptase concentration were measured using commercially available kits. RESULTS: Significantly higher concentrations of urinary LTE4 and 9alpha, 11beta-PGF2, which immediately decreased during clinical remission, were observed in the anaphylactic patients than in asthmatic patients on acute exacerbation and healthy control subjects. Concentrations of EDN and LTBG were not significantly different among the anaphylactic patients, asthmatic patients on acute exacerbation and healthy subjects. There was a significant correlation between urinary LTE4 and 9alpha, 11beta-PGF2 concentrations in the anaphylactic patients (r=0.672, P=0.005, n=32). In addition, LTE4 concentration in patients with anaphylactic shock is significantly elevated compared with that in patients without anaphylactic shock. CONCLUSIONS: This is a report on the significant increase in urinary LTE4 and 9alpha, 11beta-PGF2 concentrations during anaphylaxis. Urinary LTE4 and 9alpha, 11beta-PGF2 concentrations may be a reliable marker of endogenous production of inflammatory mediators associated with anaphylaxis.


Assuntos
Anafilaxia/fisiopatologia , Dinoprosta/urina , Mediadores da Inflamação/urina , Leucotrieno E4/urina , Mastócitos/imunologia , Adolescente , Adulto , Anafilaxia/imunologia , Anafilaxia/urina , Asma/imunologia , Asma/urina , Cisteína/urina , Feminino , Humanos , Leucotrienos/urina , Masculino , Mastócitos/metabolismo , Pessoa de Meia-Idade , Prostaglandina D2/urina , Adulto Jovem
5.
Clin Exp Allergy ; 39(9): 1348-52, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19438588

RESUMO

BACKGROUND: There has been no information about the concentration of 14,15-leukotriene C4, which is generated by 15- and 12-lipoxygenase and has been recently named eoxin C4, in biological fluids. OBJECTIVE: To determine the clinical concentrations of eoxin C4 in various respiratory inflammatory diseases, we quantified eoxin C4 in relation to the concentrations of cysteinyl-leukotrienes (CysLTs) and 15-hydroxyeicosatetraenoic acid (15-HETE) in bronchoalveolar lavage fluid (BALF). METHODS: BALF fluid was obtained from patients with a number of inflammatory lung diseases. Eoxin C4 and CysLTs were quantified by enzyme immunoassay in combination with high-performance liquid chromatography. Eoxin C4 immunoassay does not detect eoxin D4 or eoxin E4. 15-HETE was quantified by gas chromatography-mass spectrometry using (18)O-labeled compounds as an internal standard. RESULTS: The concentration of eoxin C4 (median 1.4, range <1.12-6.7 pg/mL) was significantly lower than that of eoxin C4 or CysLTs (P<0.0001). The concentration of 15-HETE significantly correlated with those of LTC4 and CysLTs or the number and the percentage of eosinophils in BALF. On the other hand, eoxin C4 concentration did not correlate with eosinophil number or CysLTs concentration in BALF. CONCLUSIONS: This is the first study demonstrating the presence of eoxin C4 in human biological fluids. Further studies are necessary to elucidate the pathophysiological role of eoxin C4 in some respiratory inflammatory diseases.


Assuntos
Líquido da Lavagem Broncoalveolar , Leucotrienos/metabolismo , Pneumopatias/metabolismo , Araquidonato 12-Lipoxigenase/metabolismo , Araquidonato 15-Lipoxigenase/metabolismo , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Imunoensaio , Leucotrieno C4/análise , Leucotrieno C4/metabolismo , Leucotrienos/análise , Masculino
6.
Thorax ; 63(12): 1076-82, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18757457

RESUMO

BACKGROUND: A diagnosis of aspirin-intolerant asthma requires aspirin provocation in specialist clinics. Urinary leukotriene E(4) (LTE(4)) is increased in aspirin-intolerant asthma. A study was undertaken to investigate new biomarkers of aspirin intolerance by comparing basal levels of cysteinyl-leukotrienes (CysLTs) and leukotriene B(4) (LTB(4)) in saliva, sputum and ex vivo stimulated blood in subjects with aspirin-intolerant and aspirin-tolerant asthma. The effects of aspirin- and allergen-induced bronchoconstriction on leukotriene levels in saliva and ex vivo stimulated blood were also compared with the effects of the provocations on urinary mediators. METHODS: Induced sputum, saliva, urine and blood were obtained at baseline from 21 subjects with asthma. At a separate visit, 11 subjects showed a positive response to lysine-aspirin inhalation and 10 were aspirin tolerant. Saliva, blood and urine were also collected on the provocation day. Analyses of CysLTs and LTB(4) and the prostaglandin D(2) metabolite 9alpha,11beta-prostaglandin F(2) were performed and the fraction of exhaled nitric oxide was measured. RESULTS: Subjects with aspirin-intolerant asthma had higher exhaled nitric oxide levels and higher baseline levels of CysLTs in saliva, sputum, blood ex vivo and urine than subjects with aspirin-tolerant asthma. There were no differences in LTB(4) levels between the groups. Levels of urinary LTE(4) and 9alpha,11beta-prostaglandin F(2) increased after aspirin provocation whereas leukotriene levels in saliva and ex vivo stimulated blood did not increase. CONCLUSION: These findings support a global and specific increase in CysLT production in aspirin-intolerant asthma. Measurement of CysLTs in saliva has the potential to be a new and convenient non-invasive biomarker of aspirin-intolerant asthma.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Aspirina/efeitos adversos , Asma/induzido quimicamente , Cisteína/análise , Hipersensibilidade a Drogas/etiologia , Leucotrienos/análise , Adulto , Biomarcadores/análise , Dinoprosta/metabolismo , Hipersensibilidade a Drogas/metabolismo , Feminino , Humanos , Leucotrieno B4/análise , Masculino , Pessoa de Meia-Idade , Saliva/química , Escarro/química , Uteroglobina/análise
7.
Eur Respir J ; 32(2): 437-42, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18417515

RESUMO

Although eosinophils produce cysteinyl leukotrienes (CysLTs) in large quantities, information on the relationship between CysLTs and eosinophilic pneumonia (EP) is lacking. Inflammatory mediator concentrations in urine were quantified to clarify the relationship between CysLT concentrations and EP severity. Leukotriene (LT)E(4), eosinophil-derived neurotoxin (EDN), 9alpha,11beta-prostaglandin F2 and LTB(4) glucuronide concentrations were quantified in the urine of: EP patients during acute exacerbation and clinical remission; asthmatic patients during acute exacerbation and under stable conditions; and healthy control subjects. The urinary LTE(4) and EDN concentrations of EP patients during acute exacerbation were significantly higher than those of asthmatic patients and healthy subjects, and decreased immediately during clinical remission. The urinary LTE(4) concentration was associated with the urinary EDN concentration of EP patients during acute exacerbation. The urinary LTE(4) concentration significantly correlated with the diffusing capacity of the lung for carbon monoxide in EP patients during acute exacerbation. The increased urinary concentrations of leukotriene and eosinophil-derived neurotoxin were associated with acute exacerbation in eosinophilic pneumonia patients. The increased leukotriene concentration significantly correlated with diffusing capacity of the lung for carbon monoxide, suggesting that the monitoring of leukotriene concentration may aid in the management of eosinophilic pneumonia patients.


Assuntos
Leucotrieno E4/urina , Eosinofilia Pulmonar/urina , Adolescente , Adulto , Idoso , Asma/metabolismo , Estudos de Casos e Controles , Feminino , Glucuronídeos/metabolismo , Humanos , Inflamação , Masculino , Pessoa de Meia-Idade , Neurotoxinas/metabolismo , Indução de Remissão
8.
Clin Exp Allergy ; 38(12): 1866-74, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19037963

RESUMO

BACKGROUND: Collection of exhaled breath condensate (EBC) is a simple, non-invasive method of obtaining samples from the airways and it can be repeated in short intervals without side effects; therefore, it provides an opportunity to monitor the changes in concentration of inflammatory mediators in the airways. However, EBC analysis still has several unresolved issues. OBJECTIVE: To better understand the characteristics of EBC, we compared cysteinyl leukotriene (CysLT) concentrations between bronchoalveolar lavage fluid (BALF) and EBC. We also attempted to correct CysLT concentrations in BALF and EBC diluted with saline and water vapour using biological markers. METHODS: EBC was collected from 14 patients with idiopathic pulmonary fibrosis before bronchoscopy. We measured CysLT concentrations and also quantified tyrosine, urea and total protein as possible biomarkers for correcting dilution. RESULTS: (1) We have validated the quantification of CysLTs in EBC. (2) Although a significant correlation was observed among tyrosine and urea concentrations in BALF, urea and total protein concentrations were below the detection limit in EBC. (3) CysLT concentrations were higher in BALF than in EBC (median, 15.96 pg/mL vs. 5.5 pg/mL; P=0.001) and there was no correlation of CysLT concentrations in BALF with those in EBC. A significant correlation of the ratio of total CysLT concentration to tyrosine concentration (CysLT/Y) in EBC with that in BALF was observed (r=0.547, P=0.043). (4) CysLT/Y in EBC correlated with serum KL-6 concentration and total cell count in BALF, and CysLT/Y in BALF also correlated with exhaled NO concentration and %VC. CONCLUSIONS: CysLT/Y in EBC significantly correlated with that in BALF and some clinical parameters correlated with CysLT/Y. Tyrosine concentration may be used to correct the dilution error for CysLT concentrations, and CysLT/Y in EBC can be a surrogate marker for CysLT concentrations in BALF.


Assuntos
Testes Respiratórios , Líquido da Lavagem Broncoalveolar/imunologia , Cisteína/análise , Expiração , Fibrose Pulmonar Idiopática/imunologia , Leucotrienos/análise , Biomarcadores/análise , Feminino , Humanos , Fibrose Pulmonar Idiopática/fisiopatologia , Pulmão/imunologia , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tirosina/análise , Ureia/análise
9.
Aliment Pharmacol Ther ; 47(1): 104-113, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29035002

RESUMO

BACKGROUND: With the development of direct-acting anti-virals (DAAs), almost all patients with chronic hepatitis C virus (HCV) infection can achieve sustained viral response (SVR). AIM: To evaluate the short-term risk of HCC among patients with SVR by DAAs, including those with cirrhosis or previous HCC. METHODS: This large-scale, multicentre cohort study included 1,675 consecutive patients who achieved SVR by treatment with interferon-free sofosbuvir-based regimens, divided into groups with (n = 152) or without previous HCC (n = 1,523). The Kaplan-Meier method and Cox proportional hazard analysis were used to calculate the cumulative HCC incidence and related factors of HCC. RESULTS: During the follow-up period (median: 17 months), 46 (2.7%) patients developed HCC. The 1-year cumulative rates of de novo HCC were 0.4% and 4.9% for the noncirrhosis and cirrhosis groups respectively (log-rank test: P < 0.001). For cirrhotic patients, serum α-fetoprotein level at the end of treatment (EOT-AFP) was the strongest predictor of de novo HCC. The 1-year cumulative de novo HCC rates were 1.4% and 13.1% in the EOT-AFP < 9.0 ng/mL and ≥ 9.0 ng/mL groups (cut-off value) respectively (log-rank test: P < 0.001). The 1-year cumulative rates of HCC recurrence were 6.5% and 23.1% for the noncirrhosis and cirrhosis groups respectively (log-rank test: P = 0.023). For cirrhotic patients, previous HCC characteristics were significantly associated with HCC recurrence. In contrast, sex, age and metabolic features did not influence de novo HCC or recurrence. CONCLUSIONS: For cirrhotic patients after elimination of HCV, serum EOT-AFP level and previous HCC characteristics would be useful markers for predicting de novo HCC or recurrence.


Assuntos
Antivirais/uso terapêutico , Carcinoma Hepatocelular/epidemiologia , Hepatite C Crônica/tratamento farmacológico , Neoplasias Hepáticas/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Carcinoma Hepatocelular/patologia , Estudos de Coortes , Feminino , Hepacivirus/efeitos dos fármacos , Humanos , Incidência , Cirrose Hepática/tratamento farmacológico , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Fatores de Risco , Adulto Jovem , alfa-Fetoproteínas/análise
10.
Oncogene ; 20(27): 3464-74, 2001 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-11429693

RESUMO

The signal transducer and activator of transcription (STAT) 3 is essential for mediating signals from the receptors for a variety of cytokines and growth factors, including IL-6 and EGF, and from cytoplasmic tyrosine kinases. Upon stimulation, STAT3 is phosphorylated at Ser727 and Tyr705. However, the role of phosphorylation at Ser727, and the kinase pathways responsible for this phosphorylation in IL-6 signaling remain obscure. Here we show that IL-6 activates at least two distinct STAT3 serine kinase pathways and that an H7-sensitive pathway is dominant over a PD98059-sensitive one in HepG2 cells stimulated with a low concentration of IL-6. The analysis, using a series of chimeric receptors containing the extracellular domain of the G-CSF receptor, the truncated form of gp 130, and additional short peptides at the gp 130 carboxy-terminus, showed that the YXXQ motif of gp 130 was sufficient for the H7-sensitive STAT3 Ser727 phosphorylation. This YXXQ-mediated pathway does not involve Erk, p38, JNK, or PKCdelta, and requires a site in the region from 533 to 711 of STAT3 for phosphorylation in vivo. Moreover, we show that Ser727 is required for full transcriptional activity of STAT3 for two different response elements. Thus, the YXXQ motif regulates STAT3 activities in two ways in response to even a low concentration of IL-6: it recruits STAT3 to the receptor for tyrosine phosphorylation, and activates an unidentified H7-sensitive pathway leading to the serine phosphorylation of STAT3.


Assuntos
1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , Antígenos CD/metabolismo , Proteínas de Ligação a DNA/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas Quinases/metabolismo , Transativadores/metabolismo , Células 3T3 , Alanina , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Antígenos CD/química , Sítios de Ligação , Carcinoma Hepatocelular , Linhagem Celular , Receptor gp130 de Citocina , Primers do DNA , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Fator Estimulador de Colônias de Granulócitos/farmacologia , Humanos , Interferon gama/farmacologia , Interleucina-6/farmacologia , Neoplasias Hepáticas , Glicoproteínas de Membrana/química , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Fosforilação , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes/farmacologia , Fator de Transcrição STAT3 , Serina , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Acetato de Tetradecanoilforbol/farmacologia , Transfecção , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/farmacologia
11.
Biochim Biophys Acta ; 1243(3): 386-92, 1995 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-7537102

RESUMO

Egg PC liposome as reconstituted with poly(ethylene oxide)-bearing lipid (coded as PEO-lipid (n = 15)) was remarkably endocytosed by Jurkat cell, which was a lymphoblastoma derived from human T cell. To confirm the endocytosis, two kinds of fluorescent probes (FITC-dextran and octadecyl rhodamine B) were employed. The former was loaded in the aqueous phase of the liposome, while the latter was embedded in the liposomal membrane. Both probes were found coincidentally at the same site in the cytosol, clearly suggesting that whole liposome entered the cell. The endocytosis was most obvious when PEO-lipid (n = 15) was employed above 50 mol%. FITC-Dextran entered the cell was found small dots in the cell, not dispersive. Even when octadecyl rhodamine B was used, no membrane fluorescence was observed at all. The uptake closely related to the cell metabolism as affected by the culture temperature and serum in the incubation medium. Furthermore, the addition of cytochalasin B completely prohibited the cell uptake of liposomes.


Assuntos
Endocitose , Lipossomos/metabolismo , Polietilenoglicóis/farmacologia , Linfócitos T/metabolismo , Permeabilidade da Membrana Celular , Citocalasina B/farmacologia , Dextranos , Fluoresceína-5-Isotiocianato/análogos & derivados , Corantes Fluorescentes , Humanos , Microscopia de Fluorescência , Rodaminas , Espectrometria de Fluorescência , Células Tumorais Cultivadas
12.
Biochim Biophys Acta ; 1285(2): 183-91, 1996 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-8972702

RESUMO

Direct fusion between Jurkat cell and a liposome modified with poly(ethylene oxide)-bearing lipid (PEO-lipid) was examined using diphtheria toxin fragment A (DTA) as the probe. Only the DTA-loaded liposome modified with PEO-lipid(n = 32) (n is the number of ethylene oxide units) exerted significant cytotoxicity against Jurkat cells, while liposomes lacking either the PEO-lipid or DTA did not. Liposomes modified by the PEO-lipid with shorter PEO chain(n = 5 or 15) did not show any cytotoxicity, irrespective of their DTA-loading. The cytotoxicity was observed even in the presence of cytochalasin B, an inhibitor of endocytosis. Judging from these results, we concluded that the PEO-lipid(n = 32)-modified liposome directly fused with plasma membrane of Jurkat cell.


Assuntos
Toxina Diftérica/toxicidade , Lipossomos/metabolismo , Fusão de Membrana/fisiologia , Fragmentos de Peptídeos/toxicidade , Polietilenoglicóis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultura/farmacologia , Citocalasina B/farmacologia , Toxina Diftérica/metabolismo , Endocitose/efeitos dos fármacos , Humanos , Microscopia de Contraste de Fase , Estrutura Molecular , Fragmentos de Peptídeos/metabolismo , Polietilenoglicóis/química , Triglicerídeos/química , Triglicerídeos/farmacologia , Células Tumorais Cultivadas
13.
J Leukoc Biol ; 68(4): 471-8, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11037967

RESUMO

Dermal cells expressing a macrophage C-type lectin (mMGL) were previously suggested to migrate to regional lymph nodes during the sensitization phase of delayed-type hypersensitivity (DTH). The migration seemed to be induced by the solvent used to dissolve the antigen, and the DTH response was significantly enhanced by the migration. In this study, immunohistochemical analysis of skin after epicutaneous application of one of such solvents, a mixture of acetone and dibutylphthalate (AD), revealed a transient decrease in the number of mMGL-positive cells in the dermis. A similar decrease in this cell population was also observed in an ex vivo assay with skin explants excised from AD-treated sites. Conditioned medium from organ culture of AD-treated skin induced a similar decrease of mMGL-positive cells in untreated dermis, indicating the involvement of soluble factors. mMGL-positive cells seemed to represent a unique subpopulation of F4/80-positive dermal cells.


Assuntos
Proteínas de Transporte/metabolismo , Dermatite Alérgica de Contato/patologia , Derme/patologia , Lectinas Tipo C , Lectinas/metabolismo , Macrófagos/efeitos dos fármacos , Proteínas de Membrana , Acetona/administração & dosagem , Acetona/farmacologia , Administração Cutânea , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/uso terapêutico , Antígenos de Diferenciação/análise , Assialoglicoproteínas , Fatores Biológicos/química , Fatores Biológicos/isolamento & purificação , Fatores Biológicos/fisiologia , Proteínas de Transporte/antagonistas & inibidores , Proteínas de Transporte/imunologia , Movimento Celular/efeitos dos fármacos , Tamanho Celular , Meios de Cultivo Condicionados/farmacologia , Dermatite Alérgica de Contato/imunologia , Dermatite Alérgica de Contato/terapia , Derme/efeitos dos fármacos , Derme/metabolismo , Dibutilftalato/administração & dosagem , Dibutilftalato/farmacologia , Feminino , Imunização Passiva , Interleucina-1/antagonistas & inibidores , Interleucina-1/imunologia , Lectinas/antagonistas & inibidores , Lectinas/imunologia , Macrófagos/imunologia , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos ICR , Peso Molecular , Técnicas de Cultura de Órgãos , Solventes/administração & dosagem , Solventes/farmacologia , Organismos Livres de Patógenos Específicos
14.
Mol Immunol ; 28(9): 1039-44, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1656246

RESUMO

Previous work on the cytolytic action of activated macrophages indicated that tumor necrosis factor (TNF) showed synergistic cytolytic activity with NO, which has been shown to act as a cyclic GMP (cGMP) generator [Higuchi et al., J. Immun. 144, 1425-1431, (1990)]. In this study, we investigated the relationship between the accumulation of intracellular cGMP and the cytotoxic action of TNF. It was demonstrated that TNF-mediated cell lysis was closely related to the background level of intracellular cGMP, and that the accumulation of cGMP within TNF resistant cells induced TNF sensitivity. We reached these conclusions on the basis of the following results; (1) agents (sodium nitroprusside and isobutylmethylxantine) that cause the accumulation of cGMP intracellularly increased the TNF-sensitivity of TNF-resistant cells; (2) the addition of dibutyryl cGMP to TNF-resistant cells increased the TNF-sensitivity; and (3) treatment at 40 degrees C or agents such as interferon gamma and actinomycin D, that synergistically kill tumor cells together with TNF, potentially increased the cGMP level. Therefore, intracellular cGMP may be one of the key molecules that lead to cell death caused by TNF.


Assuntos
GMP Cíclico/biossíntese , Citotoxicidade Imunológica/fisiologia , Fator de Necrose Tumoral alfa/fisiologia , Animais , Ácido Araquidônico/metabolismo , Citotoxicidade Imunológica/efeitos dos fármacos , Dibutiril GMP Cíclico/farmacologia , Sinergismo Farmacológico , Técnicas In Vitro , Interferon gama/farmacologia , Camundongos , Nitroprussiato/farmacologia , Células Tumorais Cultivadas
15.
J Immunother (1991) ; 10(4): 247-55, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1718408

RESUMO

We compared the tumoricidal activity of human monocytes cultured with interleukin-2 (IL-2) or human recombinant interferon-gamma (IFN-gamma) alone, or IFN-gamma in combination with a small amount of lipopolysaccharides (LPS). Human monocytes cultured with IL-2 for 7 days or longer, termed lymphokine-activated macrophages (LAMs), showed higher tumoricidal activity than those cultured for 1 day. In contrast, monocytes cultured with IFN-gamma alone or in combination with LPS for 7 days or longer showed lower tumoricidal activity. LAMs were identified as macrophages by nonspecific esterase staining and immunofluorescence staining with anti-CD14 antibody. LAMs were not induced in fetal calf serum-containing medium, but they were induced when colony-stimulating factor-1 was added to the medium. LAMs showed high tumoricidal activity against all human and murine tumor cell lines tested, although they showed no cytotoxic activity against human normal cells. During incubation with IL-2, tumoricidal activity of LAMs was maximal at days 8-16 and was sustained until day 28. The difference in tumoricidal mechanism between LAMs and lymphokine-activated killer (LAK) cells was also shown by using two kinds of cytotoxic assay systems. LAMs require a long incubation time to kill tumor cells, but LAK cells can kill them immediately. Furthermore, LAMs kill tumor cells with complete DNA degradation, whereas LAK cells can induce significant but not complete DNA degradation. These results indicate that LAMs and LAK cells have different tumoricidal mechanisms for killing target cells, although they were induced by incubation with the same lymphokine, IL-2.


Assuntos
Interleucina-2/farmacologia , Monócitos/imunologia , Neoplasias/imunologia , Animais , Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Células Cultivadas , Citotoxicidade Imunológica , DNA/metabolismo , Esterases/análise , Humanos , Interferon gama/farmacologia , Receptores de Lipopolissacarídeos , Lipopolissacarídeos , Fator Estimulador de Colônias de Macrófagos/farmacologia , Camundongos , Proteínas Recombinantes , Células Tumorais Cultivadas
16.
J Immunother (1991) ; 12(1): 41-9, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1322166

RESUMO

Tumor necrosis factor (TNF) has been shown to be cytotoxic to tumor cell lines in vitro, but the mechanism by which TNF exerts its cell growth-regulatory effects is not known. In this report, we used various inhibitors to investigate the sequence of events that lead to cytotoxic effects of TNF on L.P3 cells, a highly sensitive, murine fibroblast cell line. Our results indicate that mitochondrial respiration chains are damaged by a hydroxyl radical at an early stage of the cell lysis after TNF treatment. This event is followed by the activation of phospholipase A2, and finally leads to cell lysis.


Assuntos
Antineoplásicos/farmacologia , Ácido Araquidônico/metabolismo , Mitocôndrias/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Fosfolipases A/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Resistência a Medicamentos/fisiologia , Ativação Enzimática/fisiologia , Radicais Livres , Hidróxidos , Radical Hidroxila , Meliteno/fisiologia , Mitocôndrias/fisiologia , Fosfolipases A2 , Células Tumorais Cultivadas
17.
J Immunother (1991) ; 12(2): 90-7, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1504058

RESUMO

We previously reported that human macrophages cultured with IL-2 for a long period (lymphokine-activated macrophages, LAMs) showed high tumoricidal activity against human and murine leukemic cell lines through a different mechanism from lymphokine-activated killer (LAK) cells. In this report, we investigated the effects of various cytokines on the tumoricidal activity of IL-2-induced LAMs against HeLa cells. CSF-1 and IL-1 were found to enhance the tumoricidal activity of LAM in a dose-dependent manner, whereas IFN-gamma and TNF had inhibitory effects. CSF-1 in combination with a low dose of IL-2 synergistically induced LAMs with highly tumoricidal activity. We also found that monocytes from some donors that did not respond to IL-2 were differentiated to tumoricidal macrophages by treatment with a combination of CSF-1 and IL-2. Furthermore, IL-2-induced LAMs were found to produce cytotoxic factors in the culture medium when they were cocultured with tumor cells, and the cytotoxic activity in the culture supernatant of LAMs was also increased by the incubation of LAMs with CSF-1. The cytotoxicity of the supernatants from macrophages with different tumoricidal activity correlated with their cell-mediated cytotoxicity. It is suggested from these results that the cytotoxicity of LAMs is regulated by CSF-1, IL-1, IFN-gamma, and TNF, and that the production of cytotoxic molecules is involved in cell-mediated killing by LAMs.


Assuntos
Citocinas/farmacologia , Interleucina-2/farmacologia , Monócitos/imunologia , Citotoxicidade Imunológica , Células HeLa , Humanos , Técnicas In Vitro , Ativação de Macrófagos , Fator Estimulador de Colônias de Macrófagos/farmacologia , Macrófagos/imunologia
18.
Clin Pharmacol Ther ; 63(3): 354-66, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9542479

RESUMO

The pharmacokinetics and pharmacodynamics of FK143, a new nonsteroidal inhibitor of steroid 5 alpha-reductase, were investigated in healthy volunteers, with use of plasma FK143 concentrations and serum dihydrotestosterone levels as an index for pharmacologic effects. The area under the plasma concentration-time curve from zero to infinity [AUC(0-infinity)] and maximum plasma concentration [Cmax] were increased dose proportionally after oral administration (100 to 500 mg) while subjects were in the fed state. The AUC(0-infinity) and Cmax after 500 mg oral administration during fed conditions were significantly larger than those during the fasted state, suggesting an increase of the absorption of FK143. Dihydrotestosterone concentrations after a single administration of FK143 (100 to 500 mg) during fed conditions decreased to about 65% of predose values and thereafter slowly recovered to the same levels as predose values at 168 hours. A combined pharmacokinetic-pharmacodynamic model was constructed with use of changes in dihydrotestosterone concentrations. The pharmacokinetic-pharmacodynamic profiles of FK143 after repeated administration were predictable with use of the pharmacokinetic-pharmacodynamic parameters obtained after a single administration of FK143.


Assuntos
Inibidores de 5-alfa Redutase , Inibidores Enzimáticos/farmacologia , Indóis/farmacologia , Fenilbutiratos/farmacologia , Administração Oral , Área Sob a Curva , Proteínas Sanguíneas/metabolismo , Di-Hidrotestosterona/sangue , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/farmacocinética , Hormônio Foliculoestimulante/sangue , Humanos , Hidrocortisona/sangue , Indóis/administração & dosagem , Indóis/farmacocinética , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Fenilbutiratos/administração & dosagem , Fenilbutiratos/farmacocinética , Ligação Proteica , Fatores de Tempo
19.
J Nucl Med ; 39(12): 2161-6, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9867162

RESUMO

UNLABELLED: The fate of 166Ho-chitosan complex, a radiopharmaceutical drug for cancer therapy, was determined by studying its absorption, distribution and excretion in rats and mice. METHODS: Holmium-166-chitosan complex [0.75 mg of Ho(NO3)3 x 5H2O and 1 mg chitosan/ head] was administered intrahepatically to male rats. Radioactive concentrations in blood, urinary and fecal excretion and radioactive distribution in tissues were examined. To determine the effects of chitosan in 166Ho-chitosan complex, 166Ho alone [0.75 mg of Ho(NO3)3 x 5H2O/head] was intrahepatically administered to male rats, and radioactive concentrations in blood, urinary and fecal excretion and radioactive distribution were examined. In B16 melanoma-transplanted nude mice, radioactive distribution after intratumoral administration of 166Ho-chitosan complex [0.075 mg of Ho(NO3)3 x 5H2O and 0.10 mg chitosan/head] was investigated also. RESULTS: After administration of 166Ho-chitosan complex, the radioactive concentrations in blood were low, and cumulative urinary and fecal excretions over a period of 0-72 hr were 0.53% and 0.54%, respectively. The radioactive concentrations in tissues and the whole-body autoradiography images showed that most of the administered radioactivity was localized at the administration site, and only slight radioactivity was detected from the liver, spleen, lungs and bones. On the other hand, results of intrahepatic administration of 166Ho alone showed high radioactive concentrations in the blood, and the whole-body autoradiographs showed that the administered radioactivity was distributed in many organs and tissues. These results strongly suggest that 166Ho is retained at the administration site only when it forms a chelate complex with chitosan. Autoradiographs after intratumoral administration of 166Ho-chitosan complex showed that radioactivity was localized at the site of administration without distribution to the other organs and tissues. CONCLUSION: Administered 166Ho-chitosan complex is retained at the administration site after either intrahepatic or intratumoral administration to rats or tumor-transplanted nude mice.


Assuntos
Quitina/análogos & derivados , Hólmio/farmacocinética , Compostos Organometálicos/farmacocinética , Radioisótopos/farmacocinética , Compostos Radiofarmacêuticos/farmacocinética , Animais , Autorradiografia , Quitina/sangue , Quitina/farmacocinética , Quitina/urina , Fezes , Hólmio/sangue , Hólmio/urina , Cinética , Masculino , Taxa de Depuração Metabólica , Camundongos , Camundongos Endogâmicos ICR , Camundongos Nus , Compostos Organometálicos/sangue , Compostos Organometálicos/urina , Compostos Radiofarmacêuticos/sangue , Compostos Radiofarmacêuticos/urina , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
20.
J Biochem ; 113(6): 715-20, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8370669

RESUMO

Macrophages are activated by a two-step mechanism involving at least two kinds of factors, a priming and a triggering factor, to become cytotoxic to various tumor cells. In the present study, we purified macrophage-activating factor for cytotoxicity I (MAF-C I), defined as a priming macrophage activating factor (MAF), by about 1,600-fold from the culture supernatant of a human T cell hybridoma, H3-E9-6, by a series of chromatographic procedures. We identified MAF-C I activity released from H3-E9-6 cells as interleukin-2 (IL-2) from the following findings. (i) The physicochemical properties of MAF-C I and IL-2 were almost identical. (ii) Purified MAF-C I active fraction also showed T cell proliferating activity. (iii) MAF-C I activity in the purified fraction was completely neutralized by anti-IL-2 antibodies. (iv) Human recombinant IL-2 (rIL-2), at a suboptimal dose, and lipopolysaccharide (LPS) synergistically induced monocyte-mediated cytotoxicity.


Assuntos
Interleucina-2/isolamento & purificação , Fatores Ativadores de Macrófagos/isolamento & purificação , Linfócitos T/imunologia , Citotoxicidade Imunológica , Humanos , Hibridomas/imunologia , Ativação Linfocitária , Ativação de Macrófagos
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