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1.
Sci Rep ; 14(1): 5319, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438433

RESUMO

This study investigates the impact of high-pressure hydrogen gas exposure on the structural and morphological characteristics of O-ring materials. O-ring specimens undergo two cycles of sealing under 70 MPa hydrogen gas, and their resulting variations are examined using advanced characterization techniques, including powder X-ray diffraction (PXRD), small-angle X-ray scattering (SAXS), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Our findings reveal that the lattice parameters of the O-ring material show no significant changes when exposed to 70 MPa hydrogen gas. However, in the micrometre range, the formation of a hierarchical channel morphology becomes evident. This morphology is accompanied by the separation of carbon black filler from the rubber matrix, contributing to mechanical weakening of the O-ring. These observations can be attributed to the pressure gradient that develops between the inner and outer radii of the O-ring, resulting from compression forces acting perpendicularly to the radial direction due to clamp locking.

2.
Heliyon ; 10(2): e24257, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38293378

RESUMO

Several studies have been conducted to improve combat vehicle capabilities, such as the bulletproof performance of armor and fuel efficiency through weight reduction. Titanium alloys and ceramic materials are expensive and difficult to process; therefore, they can be applied only in specific locations. In addition, arc welding, which is relatively inexpensive compared with other welding processes, is widely used in industrial fields; however, because welding is often performed in multiple passes to join one part, the productivity is reduced. Therefore, in this study, mechanical properties were investigated according to production time and heat input by applying tandem pulse gas metal arc welding (GMAW) to increase productivity. The experimental data were obtained by varying the wire feeding speed. In addition, the current-voltage waveforms were measured, and the volume shift was analyzed by comparison with images captured using a high-speed camera. To analyze the mechanical properties of the tandem weld for the welding of high-hardness armor plates, the appearance (top bead and back bead), cross-section, hardness, tensile test, impact test, and spatter generation of the welded part were analyzed. The results show that all Tank-automotive and Armaments Command (TACOM) standards for the base material were met when the tandem wire feeding speed was 11 + 11 m/min, and the single-pass process increased production speed by a factor of more than 10. Tandem pulse GMAW is shown to be a viable option for improving productivity and maintaining high-quality welds for high-hardness materials.

3.
J Breast Cancer ; 20(4): 378-385, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29285043

RESUMO

PURPOSE: Pathological complete response (pCR) of axillary lymph node (LN) is frequently achieved in patients with clinically node-positive breast cancer after neoadjuvant chemotherapy (NAC). Treatment of the axilla after NAC is not well established and the value of sentinel LN biopsy following NAC remains unclear. This study investigated the predictive value of axillary response following NAC and evaluated the predictive value of a model based on axillary response. METHODS: Data prospectively collected on 201 patients with clinically node-positive breast cancer who were treated with NAC and underwent axillary LN dissection (ALND) were retrieved. A model predictive of axillary pCR was developed based on clinicopathologic variables. The overall predictive ability between models was compared by receiver operating characteristic (ROC) curve analysis. RESULTS: Of 201 patients who underwent ALND after NAC, 68 (33.8%) achieved axillary pCR. Multivariate analysis using axillary LN pCR after NAC as the dependent variable showed that higher histologic grade (p=0.031; odds ratio [OR], 2.537; 95% confidence interval [CI], 1.087-5.925) and tumor response rate ≥47.1% (p=0.001; OR, 3.212; 95% CI, 1.584-6.515) were significantly associated with an increased probability of achieving axillary pCR. The area under the ROC curve for estimating axillary pCR was significantly higher in the model that included tumor response rate than in the model that excluded this rate (0.732 vs. 0.649, p=0.022). CONCLUSION: Tumor response rate was the most significant independent predictor of axillary pCR in response to NAC. The model that included tumor response rate was a significantly better predictor of axillary pCR than the model that excluded tumor response rate.

4.
Korean J Parasitol ; 55(4): 421-424, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28877574

RESUMO

Sparganosis is a parasitic infection caused by the sparganum, the plercercoid of the genus Spirometra. The preoperative diagnosis of breast sparganosis is difficult in most cases because it is a rare parasitic infection less than 2% of all cases. We report a 62-year-old woman case of breast sparganosis that were confirmed by surgical removal of worms from the right breast. The radiologic images of the patient also revealed characteristic features of breast sparganosis. The patient described the migrating palpable breast mass, which strongly suggested the possibility of breast sparganosis. The treatment of choice and confirmative diagnosis for sparganosis are complete surgical extraction of the sparganum irrespective of infected site. Inspection of the mass site with detailed medical history and radiological examinations are important for preoperative diagnosis of sparganosis patients.


Assuntos
Doenças Mamárias/diagnóstico por imagem , Doenças Mamárias/cirurgia , Esparganose/diagnóstico por imagem , Esparganose/cirurgia , Animais , Doenças Mamárias/parasitologia , Doenças Mamárias/patologia , Feminino , Humanos , Mamografia , Pessoa de Meia-Idade , Esparganose/parasitologia , Esparganose/patologia , Plerocercoide/isolamento & purificação
5.
Health Phys ; 113(4): 304-314, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28796752

RESUMO

To expand the application of dose rate spectroscopy to the environment, the method using an environmental radiation monitor (ERM) based on a 3' × 3' NaI(Tl) detector was used to perform real-time monitoring of the dose rate and radioactivity for detected gamma nuclides in the ground around an ERM. Full-energy absorption peaks in the energy spectrum for dose rate were first identified to calculate the individual dose rates of Bi, Ac, Tl, and K distributed in the ground through interference correction because of the finite energy resolution of the NaI(Tl) detector used in an ERM. The radioactivity of the four natural radionuclides was then calculated from the in situ calibration factor-that is, the dose rate per unit curie-of the used ERM for the geometry of the ground in infinite half-space, which was theoretically estimated by Monte Carlo simulation. By an intercomparison using a portable HPGe and samples taken from the ground around an ERM, this method to calculate the dose rate and radioactivity of four nuclides using an ERM was experimentally verified and finally applied to remotely monitor them in real-time in the area in which the ERM had been installed.


Assuntos
Monitoramento Ambiental/métodos , Raios gama , Monitoramento de Radiação/métodos , Monitoramento Ambiental/instrumentação , Método de Monte Carlo , Doses de Radiação , Monitoramento de Radiação/instrumentação , Radioatividade , Radioisótopos/análise , Espectrometria gama/métodos
6.
Breast Cancer Res Treat ; 165(1): 109-118, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28573447

RESUMO

PURPOSE: The prognostic role of primary tumor surgery in women with metastatic breast cancer at diagnosis is contentious. A subset of patients who will benefit from aggressive local treatment is needed to be identified. Using a nationwide database, we developed and validated a predictive model to identify long-term survivors among patients who had undergone primary tumor surgery. METHODS: A total of 150,043 patients were enrolled in the Korean Breast Cancer Registry between January 1990 and December 2014. Of these, 2332 (1.6%) presented with distant metastasis at diagnosis. Using Cox proportional hazards regression, we developed and validated a model that predicts survival in patients who undergo primary tumor surgery, based on the clinicopathological features of the primary tumor. RESULTS: A total of 2232 metastatic breast cancer patients were reviewed. Of these, 1541 (69.0%) patients had undergone primary tumor surgery. The 3-year survival rate was 62.6% in this subgroup. Among these patients, advanced T-stage, high-grade tumor, lymphovascular invasion, negative estrogen receptor status, high Ki-67 expression, and abnormal CA 15-3 and alkaline phosphatase levels were associated with poor survival. A prediction model was developed based on these factors, which successfully identified patients with remarkable survival (score 0-3, 3-year survival rate 87.3%). The clinical significance of the model was also validated with an independent dataset. CONCLUSIONS: We have developed a predictive model to identify long-term survivors among women who undergo primary tumor surgery. This model will provide guidance to patients and physicians when considering surgery as a treatment modality for metastatic breast cancer.


Assuntos
Neoplasias da Mama/cirurgia , Sobreviventes de Câncer , Técnicas de Apoio para a Decisão , Mastectomia , Adulto , Idoso , Idoso de 80 Anos ou mais , Fosfatase Alcalina/análise , Biomarcadores Tumorais/análise , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Distribuição de Qui-Quadrado , Bases de Dados Factuais , Feminino , Humanos , Estimativa de Kaplan-Meier , Antígeno Ki-67/análise , Mastectomia/efeitos adversos , Mastectomia/mortalidade , Pessoa de Meia-Idade , Mucina-1/análise , Análise Multivariada , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias , Seleção de Pacientes , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Receptores de Estrogênio/análise , Sistema de Registros , Reprodutibilidade dos Testes , República da Coreia , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
7.
J Hazard Mater ; 331: 13-20, 2017 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-28242524

RESUMO

Radioactivities of 3H and 14C in spent radioactive ion exchange resins and spent radioactive lubricant oils released from nuclear power plants, has been determined using a combustion and sorption method (combustion method). The liquid scintillation counting (LSC) spectra showed that the interference of other radionuclides has not significantly affected the determination of radioactivities of 3H and 14C in the radwaste samples. The chemical structure of 14CO2, which originated from the combustion of radwastes, trapped 14C sorbent has been investigated using Fourier transform infrared spectroscopy (FT-IR). FT-IR study showed interesting results that peaks for uncoupled CO2 and carbonic amide appeared at FT-IR spectra of CO2 high-absorbed 14C sorbents, while the peak for carbamate was only observed at the spectra of CO2 low-absorbed sorbents. During the CO2 sorption in 14C sorbent, temperature and viscosity of the sorbent increased owing to decrease of enthalpy and increase of apparent molecular weight of the sorbent caused by the bonding formation between sorbent molecules.

8.
Appl Radiat Isot ; 126: 293-295, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28162867

RESUMO

We analyzed the consumer goods containing NORM by ICP-MS and evaluated the external dose. To evaluate the external dose, we assumed the small room model as irradiation scenario and calculated the specific effective dose rate using MCNPX code. The external doses for twenty goods are less than 1 mSv considering the specific effective dose rates and usage quantities. However, some of them have relatively high dose and the activity concentration limits are necessary as a screening tool.


Assuntos
Radiação de Fundo , Qualidade de Produtos para o Consumidor , Radioisótopos/análise , Roupas de Cama, Mesa e Banho , Humanos , Joias/análise , Espectrometria de Massas , Modelos Biológicos , Doses de Radiação , Radiometria , República da Coreia
9.
Health Phys ; 111(3 Suppl 3): S183-S192, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27676598

RESUMO

The simultaneous determination of the depth of an embedded source and its radioactivity in the medium at the environmental surveys is a very useful and advisable method for an in-situ gamma-ray measurement with respect to the time and cost constraint. An algorithm for the determination of the source depth and its radioactivity in the medium was developed using the information on the uncollided photon fluences and measured net count rates, which mean not scattered fluences and background subtracted count rate, at the detector positions. Uncollided photon fluences were calculated at several source depths in the medium as well as at detector positions from the Monte Carlo N-Particle (MCNP) simulation. The results were then used to establish a database to output their values according to the source depth in the medium by inputting the photon energy and detector position from the medium. A simple program about the simultaneous determination of two variables was applied to the results on a task to find out the depth and activity of Cs and Cs at in-situ gamma-ray spectrometry. Less than 10% and 15% differences compared with the real values at the source depth and radioactivity, respectively, were achieved using the developed program.

10.
Appl Radiat Isot ; 97: 1-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25527894

RESUMO

An investigation into the distribution of natural radionuclides and radioactive secular equilibrium in raw materials and by-products in a domestic distribution was conducted to deduce the optimum conditions for the analytical evaluation of natural radionuclides for (238)U, (226)Ra, and (232)Th using a gamma-ray spectrometer and inductively coupled plasma mass spectrometer (ICP-MS). The range of the specific activities of natural radionuclides was first evaluated by analyzing (228)Ac and (214)Bi, which are (232)Th and (226)Ra indicators, respectively, in about 100 samples of raw materials and by-products through a gamma-ray spectrometer. From further experiments using several samples selected based on the results of the distribution of natural radionuclides, the validation of their analytical evaluations for the indirect measurements using a gamma-ray spectrometer and direct measurements using ICP-MS was assured by comparing their results. Chemically processed products from the raw materials, such as Zr sand and ceramic balls, were generally shown for the type of bead and particularly analyzed showing a definite disequilibrium with above a 50% difference between (238)U and (226)Ra in the uranium series and (232)Th and (228)Ra in the thorium series.

11.
Inflamm Res ; 63(1): 53-60, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24142298

RESUMO

OBJECTIVE: Asthma is an inflammatory disease of the lung that is characterized by airway hyperresponsiveness and the increase of inflammatory cell infiltration into the airways. Naturally occurring flavones have potent anti-inflammatory effects, but their effects on asthmatic responses are still relatively unknown. METHODS: We evaluated the inhibitory effects of flavone derivatives having the chromone moiety on the immediate-phase asthmatic response (IAR) and the late-phase asthmatic response (LAR) to aerosolized-ovalbumin (OA) exposure in conscious OA-sensitized guinea pigs. RESULTS: Luteolin and apigenin (30 mg/kg, p.o.) significantly (P < 0.05) decreased not only the specific airway resistance (sRaw) in IAR and LAR, but also the recruitment of leukocytes and the release of histamine and activities of phospholipase A2 (PLA2) and eosinophil peroxide (EPO) in bronchoalveolar lavage fluid (BALF), compared to control. However, their anti-asthmatic activities were less than those of cromolyn sodium and dexamethasone. CONCLUSIONS: These results indicate that flavones containing more hydroxyl radicals have a greater anti-asthmatic effect. The potencies of flavone anti-asthmatic activities are, in order: luteolin ≥ apigenin > baicalein > chrysin > flavone.


Assuntos
Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Eosinofilia/tratamento farmacológico , Flavonas/uso terapêutico , Resistência das Vias Respiratórias/efeitos dos fármacos , Alérgenos , Animais , Antiasmáticos/farmacologia , Asma/imunologia , Asma/patologia , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Eosinofilia/imunologia , Eosinofilia/patologia , Flavonas/farmacologia , Cobaias , Histamina/imunologia , Leucócitos/efeitos dos fármacos , Leucócitos/imunologia , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/patologia , Masculino , Ovalbumina , Fosfolipases A2/imunologia
12.
Radiat Prot Dosimetry ; 155(2): 236-40, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23230217

RESUMO

The linear attenuation coefficient is an important factor in the correction of self-attenuation. In this study, a cone beam from a source of ∼1 µCi was utilised, not equipped with the collimator, and a complete geometric configuration was mathematically modelled. Samples of NaCl, Na2CO3 and (NH4)2SO4 were used to verify the mathematical model. The linear attenuation coefficient can be calculated within ∼4 % of difference in the cylindrical sample at energies of 59.5, 121.8, 244.7, 344.2 and 444.0 keV.


Assuntos
Sulfato de Amônio/química , Carbonatos/química , Modelos Teóricos , Cloreto de Sódio/química , Espectrometria gama/instrumentação , Raios gama , Fótons , Espalhamento de Radiação
13.
Phytother Res ; 25(3): 387-95, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20734328

RESUMO

It was reported previously that dibenzylbutyrolactone lignans from Forsythia viridissima fruits, which are traditional medicines for the treatment of inflammatory diseases, have antiinflammatory effects. In this study, the effects on the immediate-phase response (IAR) and late-phase response (LAR) following aerosolized-ovalbumin challenge in ovalbumin-sensitized guinea-pigs were evaluated by measuring the specific airway resistance (sRaw), recruitment of leukocytes and chemical mediators in the bronchoalveolar lavage fluids (BALF) as well as a histopathological survey. Arctiin and matairesinol at 12.5 mg/kg significantly (p < 0.05) decreased sRaw by 51.83% and 43.15% in IAR and by 47.41% and 35.43% in LAR, respectively, whereas arctigenin at 25 mg/kg was significantly active, compared with the controls. Furthermore, arctiin and arctigenin dose-dependently inhibited histamine, and the activities of phospholipase A2 (PLA2) and eosinophil peroxidase (EPO) in BALF, respectively, whereas matairesinol inhibited EPO and PLA2 at 12.5 mg/kg and histamine at 50 mg/kg, in addition, they moderately improved the infiltration of eosinophils, compared with controls. Dexamethasone, cromolyn and salbutamol significantly inhibited sRaw in both IAR and LAR, and the recruitment of leukocytes and chemical mediators, whereas salbutamol did not alter chemical mediators, in BALF. These results indicate the three lignans have antiasthmatic effects which were less active than those of the reference drugs.


Assuntos
4-Butirolactona/análogos & derivados , Antiasmáticos/farmacologia , Asma/tratamento farmacológico , Forsythia/química , Lignanas/farmacologia , Resistência das Vias Respiratórias/efeitos dos fármacos , Albuterol/farmacologia , Animais , Líquido da Lavagem Broncoalveolar , Cromolina Sódica/farmacologia , Dexametasona/farmacologia , Modelos Animais de Doenças , Peroxidase de Eosinófilo/análise , Frutas/química , Cobaias , Masculino , Estrutura Molecular , Ovalbumina/farmacologia , Fosfolipases A2/análise , Extratos Vegetais/farmacologia
14.
Phytomedicine ; 18(2-3): 134-42, 2011 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-20739157

RESUMO

Clerodendron trichotomum leaves and Rumex aquatica herbs are used as a folk medicine for the treatment of inflammatory diseases, but their active ingredients are not known until now. We isolated caffeic acid and phenylpropanoid glycosides, 1-O-caffeoyl glycoside and acteoside [ß-(3',4'-dihydroxyphenyl) ethyl-O-α-l-rhamnopyranosyl(1→3)-ß-d-(4-O-caffeoyl)-glucopyranoside] from their ethylacetate fractions, respectively, and evaluated their anti-asthmatic effects on the aerosolized ovalbumin (OA) challenge in the OA-sensitized guinea-pigs measuring the specific airway resistance (sRaw) during the immediate-phase response (IAR) and late-phase response (LAR), and also measured recruitment of leukocytes and chemical mediators on the bronchoalveolar lavage fluids (BALF) in LAR, as well as histopathological survey. Acteoside and 1-O-caffeoyl glycoside (25mg/kg) significantly (P<0.05) inhibited sRaw by 32.14 and 26.79% in IAR, and by 55.88% and 52.94% in LAR, respectively, whereas caffeic acid (25mg/kg) inhibited sRaw by 30.36% in IAR and 44.12% in LAR, compared to control, but with less effective than dexamethasone, disodium cromoglycate, and salbutamol, respectively. In addition, phenylpropanoid glycosides (25mg/kg) significantly inhibited the recruitments of leukocytes, particularly neutrophils and eosinophils into lung, Furthermore, 1-O-caffeoyl glycoside, acteoside and caffeic acid significantly (P<0.05) inhibited protein content at a dose of 25mg/kg, and histamine content and PLA(2) activity at a dose of 50mg/kg, in BALF. Acteoside had more active than caffeic acid and 1-O-caffeoyl glycoside. However, their anti-asthmatic effects were less than the reference drugs. These results indicated that caffeic acid and its glycosides (25mg/kg) have anti-asthmatic effect as the same manner with dexamethasone and disodium cromoglycate.


Assuntos
Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Clerodendrum/química , Glicosídeos/uso terapêutico , Fenóis/uso terapêutico , Fitoterapia , Rumex/química , Resistência das Vias Respiratórias/efeitos dos fármacos , Albuterol/farmacologia , Albuterol/uso terapêutico , Animais , Antiasmáticos/farmacologia , Asma/metabolismo , Asma/patologia , Líquido da Lavagem Broncoalveolar , Ácidos Cafeicos/farmacologia , Ácidos Cafeicos/uso terapêutico , Cromolina Sódica/farmacologia , Cromolina Sódica/uso terapêutico , Dexametasona/farmacologia , Dexametasona/uso terapêutico , Glucosídeos/farmacologia , Glucosídeos/uso terapêutico , Glicosídeos/farmacologia , Cobaias , Histamina/metabolismo , Leucócitos/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Masculino , Infiltração de Neutrófilos/efeitos dos fármacos , Ovalbumina , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Folhas de Planta , Propanóis/farmacologia , Propanóis/uso terapêutico , Proteínas/metabolismo
15.
Biol Pharm Bull ; 33(11): 1847-53, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21048310

RESUMO

Previously, we reported that dibenzylbutyrolactone lignans (DBLLs) from the fruit of Forsythia koreana NAKAI (Oleaceae) has anti-inflammatory, antioxidant, and anti-asthmatic effects. In this study, to clarify the anti-inflammatory mechanisms of DBLL, we evaluated the effects of DBLLs on lipopolysaccharide-stimulated inducible nitric oxide synthetase (iNOS) and cyclooxygenase-2 (COX-2) expressions, nitric oxide (NO) and prostaglandin E(2) (PGE(2)) productions, nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) activations, inhibitor of κB (IκB) and inhibitor of κB kinase (IKK) phosphorylations in cytosolic proteins, and cytotoxicity in Raw264.7 cells. DBLLs potently suppressed both the enzyme expression and DNA-binding activity of NF-κB. Arctiin, arctigenin (1.0 µM) and matairesinol (10 µM) inhibited the expression of iNOS by 37.71±2.86%, 32.51±4.28%, and 27.44±2.65%, respectively, and arctiin, arctigenin (0.1 µM) and matairesinol (1.0 µM) inhibited COX-2 expression by 37.93±7.81%, 26.70±4.61% and 29.37±5.21%, respectively. The inhibitory effects of DBLLs on NO and PGE(2) productions were the same patterns as those seen for the reductions in iNOS and COX-2 expression, respectively. Arctiin, arctigenin (1.0 µM) and matairesinol (10 µM) significantly (p<0.05) inhibited NF-κB DNA binding by 44.85±6.67%, 44.16±6.61%, and 44.79±5.62%, respectively, and arctiin (0.1 µM) and arctigenin (1.0 µM) significantly (p<0.05) inhibited the phosphorylation of IκB by 20.58±3.86% and 25.99±6.18%, respectively. Furthermore, arctiin, matairesinol (1.0 µM) and arctigenin (10 µM) inhibited the phosphorylation of IKK by 38.80±6.64%, 38.33±6.65%, and 38.57±8.14%, respectively. In addition, DBLLs potently inhibited the lipopolysaccharide (LPS)-induced activation of MAPKs (SAPK/c-Jun NH(2)-terminal kinase (JNK), p38, and extracellular signal receptor-activated kinase (ERK)1/2). Overall, arctiin was the most effective; its effect was nearly the same as that of 10 µM helenalin. These findings suggest that treatment with non-toxic DBLLs inhibits not only NF-κB and NF-κB-regulated protein activation, but also potently inhibits the activations of specific MAPKs.


Assuntos
Anti-Inflamatórios/farmacologia , Ciclo-Oxigenase 2/metabolismo , Forsythia/química , Lignanas/farmacologia , Macrófagos/efeitos dos fármacos , Óxido Nítrico Sintase/metabolismo , Extratos Vegetais/farmacologia , Animais , Linhagem Celular , DNA/metabolismo , Dinoprostona/biossíntese , Frutas , Quinase I-kappa B/metabolismo , Lipopolissacarídeos , Macrófagos/metabolismo , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico/biossíntese , Fosforilação , Sesquiterpenos/farmacologia , Sesquiterpenos de Guaiano
16.
Arch Pharm Res ; 33(6): 947-57, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20607501

RESUMO

We previously reported that arctigenin, a phenylpropanoid dibenzylbutyrolactone lignan isolated from Forsythia koreana, exhibits anti-inflammatory, antioxidant, and analgesic effects in animal models. In addition, arctigenin inhibited eosinophil peroxidase and activated myeloperoxidase in inflamed tissues. In this study, we tested the effects of arctigenin on type I-IV allergic inflammation and pro-inflammatory enzymes in vitro and in vivo. Arctigenin significantly inhibited the heterologous passive cutaneous anaphylaxis induced by ovalbumin in mice at 15 mg/kg, p.o., and compound 48/80-induced histamine release from rat peritoneal mast cells at 10 microM. Arctigenin (15 mg/kg, p.o.) significantly inhibited reversed cutaneous anaphylaxis. Further, arctigenin (15 mg/kg, p.o.) significantly inhibited the Arthus reaction to sheep's red blood cells, decreasing the hemolysis titer, the hemagglutination titer, and the plaque-forming cell number for SRBCs. In addition, arctigenin significantly inhibited delayed type hypersensitivity at 15 mg/kg, p.o. and the formation of rosette-forming cells at 45 mg/kg, p.o. Contact dermatitis induced by picrylchloride and dinitrofluorobenzene was significantly (p < 0.05) inhibited by surface treatment with arctigenin (0.3 mg/ear). Furthermore, arctigenin dose-dependently inhibited pro-inflammatory enzymes, such as cyclooxygenase-1 and 2, 5-lipoxygenase, phospholipase A2, and phosphodiesterase. Our results show that arctigenin significantly inhibited B- and T-cell mediated allergic inflammation as well as pro-inflammatory enzymes.


Assuntos
Antialérgicos/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Inibidores Enzimáticos/farmacologia , Furanos/farmacologia , Antagonistas dos Receptores Histamínicos/farmacologia , Hipersensibilidade/prevenção & controle , Inflamação/prevenção & controle , Lignanas/farmacologia , Animais , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Cobaias , Hemaglutinação/efeitos dos fármacos , Liberação de Histamina/efeitos dos fármacos , Inflamação/imunologia , Pulmão/efeitos dos fármacos , Pulmão/enzimologia , Pulmão/imunologia , Masculino , Mastócitos/efeitos dos fármacos , Mastócitos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Ratos , Ratos Sprague-Dawley , Pele/efeitos dos fármacos , Pele/imunologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
17.
Fitoterapia ; 81(7): 803-12, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20460144

RESUMO

We previously reported that quercetin and rutin have potent, anti-asthmatic activity, but the structure-activity relationships of flavonoids and anti-asthmatic agents are still poorly understood. In the current study, the effects of kaempferol, fisetin, and morin on the immediate-phase response (IAR) and late-phase response (LAR) caused by exposure to aerosolized-ovalbumin (OA) in OA-sensitized guinea pigs were evaluated by determining the specific airway resistance (sRaw), recruitment of leukocytes and chemical mediators in bronchoalveolar lavage fluid (BALF), histopathological surveys, and determination of neutrophil chemotaxis. Fisetin and kaempherol (30 mg/kg, p.o.) significantly (P<0.01) inhibited sRaw by 47.93% and 30.05% in IAR, and 54.45% and 40.50% in LAR, when compared to vehicle control, respectively. Furthermore, all three studied flavonols (30 mg/kg, p.o.) significantly (P<0.05) inhibited the recruitment of total, as well as subtypes of, leukocytes into the lung BALF. This recruitment inhibition corresponded to the inhibition of leukocyte infiltration, particularly of eosinophils and neutrophils, into the lung in pathological surveys and formly-methionyl-leucyl-phenylalanine (FMLP)-induced neutrophil chemotaxis studies. Kaempferol inhibited FMLP-induced neutrophil chemotaxis in a concentration-dependent manner in a tested range of 1-100 µM. Fisetin inhibited histamine content and peroxidase (EPO) activity in BALF in a dose-dependent manner. All three tested flavonols significantly (P<0.01) inhibited histamine content at 10 mg/kg, and phospholipase A(2) (PLA(2)) and EPO activities at 30 mg/kg (p.o.) in BALF. Kaempherol had a greater anti-asthmatic effect than other flavonols. Fisetin demonstrated the greatest inhibition of sRaw, whereas morin had lesser effects. These results indicate that the lower the molecular weight, the greater the anti-asthmatic activities of these compounds.


Assuntos
Resistência das Vias Respiratórias/efeitos dos fármacos , Antiasmáticos/farmacologia , Flavonóis/farmacologia , Leucócitos/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Extratos Vegetais/farmacologia , Mecânica Respiratória/efeitos dos fármacos , Administração por Inalação , Aerossóis , Resistência das Vias Respiratórias/imunologia , Animais , Lavagem Broncoalveolar , Quimiotaxia de Leucócito/efeitos dos fármacos , Relação Dose-Resposta a Droga , Eosinófilos/efeitos dos fármacos , Flavonoides/farmacologia , Cobaias , Histamina/metabolismo , Quempferóis/farmacologia , Pulmão/imunologia , Pulmão/fisiopatologia , Masculino , Peso Molecular , N-Formilmetionina Leucil-Fenilalanina , Infiltração de Neutrófilos/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Ovalbumina/administração & dosagem , Peroxidase/metabolismo , Fosfolipases A2/metabolismo , Mecânica Respiratória/fisiologia
18.
J AOAC Int ; 93(2): 462-77, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20480891

RESUMO

Egg allergy is one of the most common food allergies in both adults and children, and foods including eggs and their byproducts should be declared under food allergen labeling policies in industrial countries. Therefore, to develop and validate a sensitive and specific method to detect hidden egg allergens in foods, we compared immunochemical, DNA-based, and proteomic methods for detecting egg allergens in foods using egg allergen standards such as egg whole protein, egg white protein, egg yolk protein, ovomucoid, ovalbumin, ovotransferrin, lysozyme, and alpha-livetin. Protein-based immunochemical methods, including ELISA as an initial screening quantitative analysis and immunoblotting as a final confirmatory qualitative analysis, were very sensitive and specific in detecting potentially allergenic egg residues in processed foods in trace amounts. In contrast, the proteomics-based, matrix-assisted laser desorption/ionization time-of-flight MS and LC-tandem quadrupole time-of-flight MS methods were not able to detect some egg allergens, such as ovomucoid, because of its nondenaturing property under urea and trypsin. The DNA-based PCR method could not distinguish between egg and chicken meat because it is tissue-nonspecific. In further studies for the feasibility of these immunochemical methods on 100 real raw dietary samples, four food samples without listed egg ingredients produced a positive response by ELISA, but exhibited negative results by immunoblotting.


Assuntos
DNA/análise , Análise de Alimentos/métodos , Hipersensibilidade Alimentar/imunologia , Espectrometria de Massas/métodos , Óvulo/metabolismo , Proteínas/análise , Animais , Galinhas , Conalbumina/química , Proteínas do Ovo/química , Clara de Ovo/química , Gema de Ovo/química , Hipersensibilidade Alimentar/diagnóstico , Humanos , Muramidase/química , Ovalbumina/química , Ovomucina/química , Proteômica/métodos
19.
Fitoterapia ; 81(7): 820-5, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20466042

RESUMO

We studied effects of hydrolysable tannins on rat papillary muscle contractions induced by propranolol. The developed force of papillary muscle was measured isometrically with an inductive force transducer. The IC(50) values for digallic acid, gallic acid, germin D, praecoxin A and 1-desgalloyl rugosin F were 4.2 x 10(-5) M, 1.3 x 10(-4) M, 1,4 x 10(-4) M, 1.5 x 10(-4) and 1.7 x 10(-4) M, respectively. Incubation with tannins significantly attenuated the propranolol-induced negative inotropic contractile response. These results show that hydrolysable tannins depress muscle contractions and potentiate the activities of ß-adrenergic blocker.


Assuntos
Antagonistas Adrenérgicos beta/farmacologia , Betulaceae/química , Taninos Hidrolisáveis/farmacologia , Contração Miocárdica/efeitos dos fármacos , Músculos Papilares/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Concentração Inibidora 50 , Contração Isométrica/efeitos dos fármacos , Masculino , Músculos Papilares/fisiologia , Propranolol/farmacologia , Ratos , Ratos Sprague-Dawley
20.
Arch Pharm Res ; 33(4): 509-14, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20422358

RESUMO

The root of Aralia cordata is a traditional medicine for the treatment of inflammation, fever, pain, and spasm in the various diseases in Korea. We isolated a dibenzylbutyrolactone diterpene acid, 7-oxosandaracopimaric acid (OSA), from the ether fraction of Aralia cordata MeOH extract, and studied the effect of OSA on phenylquinone (PQ)-induced writhing syndrome and PQ-induced capillary permeability increase, compound 48/80-induced histamine release by peritoneal mast cells, cycloxygenase (COX) activities, and silica-induced RAW 264.7 cell reactive oxygen species production. OSA (30 mg/kg, p.o.) significantly (p < 0.05) inhibited PQ-induced writhes by 25.8% and the PQ-induced capillary permeability increase levels by 33.13% as compared with PQ control. Furthermore, OSA (10 mM) inhibited COX-1 by 22.82 +/- 1.94%, and COX-2 by 15.86 +/- 1.35%, respectively, to the same extent as indomethacin at the same concentration (10 mM). And OSA (3.0 mM) significantly (p < 0.05) inhibited compound 48/80-induced histamine release from rat mast cells, and its activity was similar to that of celebrex (1 mM), but no piracetam (0.1 mM) inhibited them. OSA did not inhibit ROS production in RAW 264.7 cells. These results indicated that OSA has analgesic and anti-inflammatory effects due to its inhibitory effects on capillary permeability, COX activities, and histamine release.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Aralia/química , Diterpenos/farmacologia , Animais , Anti-Inflamatórios não Esteroides/isolamento & purificação , Aralia/crescimento & desenvolvimento , Benzoquinonas , Permeabilidade Capilar/efeitos dos fármacos , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/metabolismo , Diterpenos/isolamento & purificação , Relação Dose-Resposta a Droga , Liberação de Histamina/efeitos dos fármacos , Masculino , Mastócitos/efeitos dos fármacos , Mastócitos/metabolismo , Medicina Tradicional Coreana , Camundongos , Camundongos Endogâmicos ICR , Dor/tratamento farmacológico , Raízes de Plantas/química , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Ovinos
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