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1.
Neurocrit Care ; 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39117963

RESUMO

BACKGROUND: This study aimed to analyze the current status of brain death/death by neurologic criteria (BD/DNC) determination in Korea over a decade, identifying key areas for improvement in the process. METHODS: We conducted a retrospective analysis of data from the Korea Organ Donation Agency spanning 2011 to 2021, focusing on donors whose donations were not completed. The study reviewed demographics, medical settings, diagnoses, and outcomes, with particular emphasis on cases classified as nonbrain death and those resulting in death by cardiac arrest during the BD/DNC assessment. RESULTS: Of the 5047 patients evaluated for potential brain death from 2011 to 2021, 361 were identified as noncompleted donors. The primary reasons for noncompletion included nonbrain death (n = 68, 18.8%), cardiac arrests during the BD/DNC assessment process (n = 80, 22.2%), organ ineligibility (n = 151, 41.8%), and logistical and legal challenges (n = 62, 17.2%). Notably, 25 (36.8%) of them failed to meet the minimum clinical criteria, and 7 of them were potential cases of disagreement between the two clinical examinations. Additionally, most cardiac arrests (n = 44, 55.0%) occurred between the first and second examinations, indicating management challenges in critically ill patients during the assessment period. CONCLUSIONS: Our study highlights significant challenges in the BD/DNC determination process, including the need for improved consistency in neurologic examinations and the management of critically ill patients. The study underscores the importance of refining protocols and training to enhance the accuracy and reliability of brain death assessments, while also ensuring streamlined and effective organ donation practices.

2.
Chemistry ; 29(36): e202300903, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37060216

RESUMO

An environmentally friendly oxidation system has proposed for the practical and scalable production of value-added 2,5-furandicarboxylic acid from 1 kg of 5-hydroxymethylfurfural. The system is composed of a simple base, oxygen, and a green solvent, thereby providing a sustainable and economical approach to organic synthesis. To gain insight into the mechanism of this oxidation process, NMR spectroscopic analysis and kinetic study are used for the mechanistic investigation of this environmentally friendly oxidation process.

3.
Arch Virol ; 159(12): 3219-30, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25091740

RESUMO

Classical swine fever (CSF), caused by the CSF virus (CSFV), is a highly contagious disease in pigs. In Korea, vaccination using a live-attenuated strain (LOM strain) has been used to control the disease. However, parenteral vaccination using a live-attenuated strain still faces a number of problems related to storage, cost, injection stress, and differentiation of CSFV infected and vaccinated pigs. Therefore, two kinds of new candidates for oral vaccination have been developed based on the translation of the E2 gene of the SW03 strain, which was isolated from an outbreak of CSF in 2002 in Korea, in transgenic rice calli (TRCs) from Oriza sativa L. cv. Dongjin to express a recombinant E2 protein (rE2-TRCs). The expression of the recombinant E2 protein (rE2) in rE2-TRCs was confirmed using Northern blot, SDS-PAGE, and Western blot analysis. Immune responses to the rE2-TRC in mice and pigs were investigated after oral administration. The administration of rE2-TRCs increased E2-specific antibodies titers and antibody-secreting cells when compared to animals receiving the vector alone (p < 0.05 and p < 0.01). In addition, mice receiving rE2-TRCs had a higher level of CD8+ lymphocytes and Th1 cytokine immune responses to purified rE2 (prE2) in vitro than the controls (p < 0.05 and p < 0.01). Pigs receiving rE2-TRCs also showed an increase in IL-8, CCL2, and the CD8+ subpopulation in response to stimulation with prE2. These results suggest that oral administration of rE2-TRCs can induce E2-specific immune responses.


Assuntos
Vírus da Febre Suína Clássica/imunologia , Oryza/genética , Plantas Geneticamente Modificadas , Vacinas Sintéticas/imunologia , Proteínas do Envelope Viral/imunologia , Vacinas Virais/imunologia , Administração Oral , Animais , Anticorpos Antivirais/sangue , Células Produtoras de Anticorpos/imunologia , Linfócitos T CD8-Positivos/imunologia , Quimiocina CCL2/metabolismo , Vírus da Febre Suína Clássica/genética , Interleucina-8/metabolismo , Coreia (Geográfico) , Camundongos , Suínos , Subpopulações de Linfócitos T/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/isolamento & purificação , Proteínas do Envelope Viral/genética , Vacinas Virais/administração & dosagem , Vacinas Virais/genética , Vacinas Virais/isolamento & purificação
4.
BMC Vet Res ; 10: 179, 2014 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-25255918

RESUMO

BACKGROUND: After the recent outbreak of foot-and-mouth disease (FMD) in Korea, a vaccination policy has been applied to control the disease. In addition, several non-specific immune stimulators have been used without any scientific evidence that they would enhance the immune response after FMD vaccination and/or protect against FMD. Based on the current situation, the aim of this study was to evaluate the effect of the non-specific immune stimulator germanium biotite on FMD vaccination and immune responses in cattle. To achieve our goal, immune responses to FMD vaccination, such as levels of IgG and IgA, antibody duration, and virus-neutralizing titers were investigated after germanium biotite feeding. The PBMC typing and proliferative response after stimulation with mitogens, the cytokines expression level of PBMC, and the lysozyme activity in the serum were measured to evaluate the immune enhancing effects of germanium biotite following its administration. RESULTS: Following the first vaccination, high level of IgG (at 4 weeks) and IgA (at 2 and 31 weeks) titers in serum and saliva were observed in the germanium biotite-feeding group (p < 0.05). The germanium biotite group also showed high and longstanding inhibition percentage value in ELISA assay at 31 weeks (p < 0.05). Generally, higher virus-neutralizing antibody titers were observed in the feeding group at 20 and 31 weeks after vaccination. Following the feeding germanium biotite, the germanium biotite group showed increased subpopulation of CD4+ lymphocytes and MHC I+II+ cells in PBMCs at 23 week, responding to stimulation of ConA. The levels of IFN-γ (at 3 and 8 weeks), IL-1α (at 3, 11, and 23 weeks), IL-1ß (at 3, 8, and 11 weeks), and IL-4 (at 8 and 11 weeks) gene expression were also significantly increased in the feeding group (p < 0.01 and p < 0.05). Feeding with germanium biotite increased the lymphocytes' proliferative response to the stimulation of ConA and LPS at 23 weeks and lysozyme activity at 9 weeks after feeding. CONCLUSIONS: These results suggest that germanium biotite feeding could increase the protection against FMD virus infection via the induction of higher humoral and cellular immune responses in cattle.


Assuntos
Doenças dos Bovinos/prevenção & controle , Suplementos Nutricionais , Febre Aftosa/prevenção & controle , Germânio/uso terapêutico , Vacinas Virais/imunologia , Ração Animal/análise , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Bovinos , Doenças dos Bovinos/imunologia , Citocinas/genética , Citocinas/metabolismo , Febre Aftosa/epidemiologia , Regulação da Expressão Gênica/fisiologia , Germânio/administração & dosagem , República da Coreia/epidemiologia , Vacinação/legislação & jurisprudência
5.
BMC Genomics ; 14: 426, 2013 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-23802650

RESUMO

BACKGROUND: Brucella abortus is an intracellular zoonotic pathogen which causes undulant fever, endocarditis, arthritis and osteomyelitis in human and abortion and infertility in cattle. This bacterium is able to invade and replicate in host macrophage instead of getting removed by this defense mechanism. Therefore, understanding the interaction between virulence of the bacteria and the host cell is important to control brucellosis. Previously, we generated internalization defective mutants and analyzed the envelope proteins. The present study was undertaken to evaluate the changes in early transcriptional responses between wild type and internalization defective mutants infected mouse macrophage, RAW 264.7. RESULTS: Both of the wild type and mutant infected macrophages showed increased expression levels in proinflammatory cytokines, chemokines, apoptosis and G-protein coupled receptors (Gpr84, Gpr109a and Adora2b) while the genes related with small GTPase which mediate intracellular trafficking was decreased. Moreover, cytohesin 1 interacting protein (Cytip) and genes related to ubiquitination (Arrdc3 and Fbxo21) were down-regulated, suggesting the survival strategy of this bacterium. However, we could not detect any significant changes in the mutant infected groups compared to the wild type infected group. CONCLUSIONS: In summary, it was very difficult to clarify the alterations in host cellular transcription in response to infection with internalization defective mutants. However, we found several novel gene changes related to the GPCR system, ubiquitin-proteosome system, and growth arrest and DNA damages in response to B. abortus infection. These findings may contribute to a better understanding of the molecular mechanisms underlying host-pathogen interactions and need to be studied further.


Assuntos
Brucella abortus/genética , Brucella abortus/fisiologia , Macrófagos/microbiologia , Mutação/genética , Transcrição Gênica , Animais , Linhagem Celular , Perfilação da Expressão Gênica , Macrófagos/citologia , Camundongos , Anotação de Sequência Molecular , Análise de Sequência com Séries de Oligonucleotídeos , Reprodutibilidade dos Testes , Fatores de Tempo
6.
Microbiol Immunol ; 57(6): 417-25, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23773020

RESUMO

An oral delivery system based on ApxIIA#5-expressed on Saccharomyces cerevisiae was studied for its potential to induce immune responses in mice. Murine bone marrow-derived dendritic cells (DCs) stimulated in vitro with ApxIIA#5-expressed on S. cerevisiae upregulated the expression of maturation and activation markers, leading to production of tumor necrosis factor-α, interleukin (IL)-1ß, IL-12p70 and IL-10. Presentation of these activated DCs to cluster of differentiation CD4+ T cells collected from mice that had been orally immunized with the ApxIIA#5-expressed on S. cerevisiae elicited specific T-cell proliferation. In addition, the orally immunized mice had stronger antigen-specific serum IgG and IgA antibody responses and larger numbers of antigen-specific IgG and IgA antibody-secreting cells in their spleens, Peyer's patches and lamina propria than did those immunized with vector-only S. cerevisiae or those not immunized. Furthermore, oral immunization induced T helper 1-type immune responses mediated via increased serum concentrations of IgG2a and an increase predominantly of IFN-γ-producing cells in their spleens and lamina propria. Our findings suggest that surface-displayed ApxIIA#5-expressed on S. cerevisiae may be a promising candidate for an oral vaccine delivery system for eliciting systemic and mucosal immunity.


Assuntos
Infecções por Actinobacillus/prevenção & controle , Actinobacillus pleuropneumoniae/imunologia , Proteínas de Bactérias/imunologia , Vacinas Bacterianas/imunologia , Proteínas Hemolisinas/imunologia , Saccharomyces cerevisiae/imunologia , Infecções por Actinobacillus/imunologia , Actinobacillus pleuropneumoniae/genética , Administração Oral , Animais , Anticorpos Antibacterianos/sangue , Proteínas de Bactérias/genética , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/genética , Linfócitos T CD4-Positivos/imunologia , Proliferação de Células , Citocinas/metabolismo , Células Dendríticas/imunologia , Proteínas Hemolisinas/genética , Imunidade nas Mucosas , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Camundongos , Saccharomyces cerevisiae/genética
7.
Sci Rep ; 13(1): 2148, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-36750725

RESUMO

Hemoglobin variability is known to increase cardiovascular mortality in chronic kidney disease, but the association of hemoglobin variability with the risk of cardiovascular disease (CVD) in the general population is yet unclear. This retrospective cohort study based on 'the South Korean National Health Insurance Service database' consisted of 198,347 adults who went through all three health examinations. Hemoglobin variability is defined as the average successive variability of three separate hemoglobin values from each health screening period. Participants were followed up for 6 years to determine the risk of coronary heart disease and stroke. We used multivariate Cox proportional hazards regression to examine the adjusted hazard ratios for CVD according to hemoglobin variability. Per 1 unit increase of hemoglobin variability, the risk for CVD (aHR 1.06, 95% CI 1.02-1.09) and stroke (aHR 1.08, 95% CI 1.03-1.13) increased significantly. The risk-increasing trend was preserved in the low-to-moderate risk group of CVDs (aHR 1.07, 95% CI 1.02-1.11). This result suggests that subjects with high hemoglobin variability who would otherwise be categorized as having low-to-moderate CVD risk may have higher risk of CVD than those with low hemoglobin variability.


Assuntos
Doenças Cardiovasculares , Hemoglobinas , Adulto , Humanos , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/epidemiologia , Hemoglobinas/análise , República da Coreia/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/epidemiologia , Medição de Risco
8.
Korean Circ J ; 51(12): 1017-1029, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34595884

RESUMO

BACKGROUND AND OBJECTIVES: While diuretics are sometimes used in atrial septal defect (ASD) treatment, their effect on ASD size reduction remains unclear. We aimed to evaluate the efficacy of diuretics in ASD size reduction in pediatric patients. METHODS: We retrospectively reviewed the medical records of patients with secundum ASD (size ≥10 mm), between 2005 and 2019. Patients were divided into two groups based on the diuretic administration. RESULTS: Of the 73 enrolled patients, 40 received diuretics. The initial age at ASD diagnosis (2.8±1.7 vs. 2.5±2.0 years, p=0.526) and follow-up duration (22.3±11.4 vs. 18.7±13.2 months, p=0.224) were not significantly different between the groups. The ASD diameter at the initial diagnosis (13.7±2.0 vs. 13.5±3.4 mm, p=0.761) and the indexed ASD diameter (25.5±5.9 vs. 26.9±10.3 mm/m², p=0.493) were also not significantly different between two groups. The ASD diameter significantly increased in the non-diuretic group during follow-up (0.0±2.9 vs. +2.6±2.0 mm, p<0.001). The indexed ASD diameter significantly decreased in the diuretic group during follow-up (-5.7±6.5 vs. +0.2±3.9 mm/m², p<0.001). In the linear mixed model analysis, diuretic use was associated with ASD diameter decrease (p<0.001) and indexed ASD diameter reduction (p<0.001) over time. Device closure was more frequently performed in the diuretic (75.0%) than in the non-diuretic group (39.4%). CONCLUSIONS: Patients receiving diuretics are less likely to undergo surgery. The diuretics administration may be associated with the use of smaller ASD devices for transcatheter treatment through ASD size reduction.

9.
PLoS One ; 15(12): e0234177, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33270634

RESUMO

To isolate Bacillus velezensis mutants with improved antifungal activity for use in the biological control of phytopathogenic fungi, wild-type Bacillus velezensis KRF-001 producing iturin, surfactin, and fengycin was irradiated by ultraviolet (UV) rays. The in vitro and in vivo antifungal activities of UV mutants and characterization of the cyclic lipopeptides produced by a selected mutant were examined. A mutant strain yielding high levels of iturin showed over 2-fold higher antifungal activity than the wild-type against Fusarium oxysporum. A potent suppressive effect of the mutant was also observed on spore germination of Botrytis cinerea, the causative agent of cucumber gray mold, at different butanol extract concentrations. Further analysis of the mutant by real-time PCR and high-performance liquid chromatography revealed increased expression of iturin and surfactin biosynthesis genes as well as enhanced production of iturin and surfactin metabolites. However, the amounts of fengycin obtained from the mutant strain BSM54 were significantly lesser than those of iturin and surfactin. Particularly, iturin A production by the mutant was 3.5-fold higher than that of the wild-type, suggesting that the higher antifungal activity of the mutant against F. oxysporum resulted from the increased expression of biosynthesis genes associated with iturin production. The commercial greenhouse experiment using soil naturally infested with Sclerotinia sclerotiorum (sclerotinia rot) and F. oxysporum (fusarium wilt) showed that the mutant strain reduced sclerotinia rot and fusarium wilt diseases (P = 0.05) more effectively than the wild-type and commercially available product Cillus® in Korea. These results suggest that the mutant with high iturin yield is a potential candidate for the development of a biological control agent in agriculture.


Assuntos
Antifúngicos/isolamento & purificação , Bacillus/isolamento & purificação , Peptídeos Cíclicos/metabolismo , Ascomicetos/crescimento & desenvolvimento , Bacillus/metabolismo , Botrytis/crescimento & desenvolvimento , Fusarium/crescimento & desenvolvimento , Lipopeptídeos/metabolismo , República da Coreia
10.
Arch Virol ; 154(8): 1361-4, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19590811

RESUMO

Hepatitis E virus (HEV) has been considered to be a zoonotic agent and an important public concern worldwide. In this study, a nested RT-PCR was developed to detect the helicase gene of swine HEV (sHEV) from sera of pigs. Using this RT-PCR, 16 out of 821 Korean isolates of sHEV were identified, with 1.9% prevalence. An age-specific prevalence was demonstrated with the highest prevalence in growing pigs (5.4%). Phylogenetic analysis of sHEV Korean isolates identified genotype 3, with 89.4-99.9% nucleotide sequence identity. The viruses were closely related to US and Japanese HEV isolates from swine and humans (89.4-93.1%). The prevalence of anti-HEV IgG in individual pigs and swine herds was 39.5 and 80%, respectively. The seroprevalence rate increased in proportion to the age of the swine. The seroprevalence of HEV was higher than previously reported. These results indicate that sHEV is widespread in Korean swine herds and further raise concerns about possible zoonosis.


Assuntos
Vírus da Hepatite E/genética , Hepatite E/epidemiologia , Hepatite E/veterinária , RNA Helicases/genética , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/virologia , Proteínas não Estruturais Virais/genética , Fatores Etários , Animais , Feminino , Anticorpos Anti-Hepatite/sangue , Vírus da Hepatite E/enzimologia , Vírus da Hepatite E/isolamento & purificação , Coreia (Geográfico)/epidemiologia , Masculino , Reação em Cadeia da Polimerase/métodos , Homologia de Sequência do Ácido Nucleico , Estudos Soroepidemiológicos , Sus scrofa , Suínos
11.
J Vet Diagn Invest ; 21(4): 510-6, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19564500

RESUMO

Adherence factors and enterotoxins are major virulence factors of enterotoxigenic Escherichia coli (ETEC). Antibiotics have been used frequently for the treatment and prevention of ETEC infection in piggeries worldwide, including Korea. Therefore, data on both virulence profiles and antibiotic resistance patterns are useful in the epidemiological study of ETEC. A total number of 198 E. coli field isolates were examined. The most prevalent pathotype was F1, followed by a combination of F1 and EAST1. All of the 71 isolates were resistant to more than 2 antibiotics used in a disk diffusion test, and 87.94% of the isolates were found to be resistant to more than 4 antibiotics. Investigations were also conducted to correlate the virulence gene profiles with antibiogram and pulsed-field gel electrophoresis (PFGE). Although a high degree of polymorphism was noted among strains having the same virulence patterns, the highest similarity pattern was observed carrying the same virulence profiles and similar antibiogram. Thus, investigation of both virulence profiles and antibiogram is essential to the epidemiological study of ETEC. Moreover, the PFGE method might be applicable as a tool to reveal genetic relatedness among E. coli strains from piggeries in Korea.


Assuntos
Eletroforese em Gel de Campo Pulsado/veterinária , Infecções por Escherichia coli/veterinária , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Genótipo , Doenças dos Suínos/microbiologia , Animais , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Coreia (Geográfico)/epidemiologia , Filogenia , Suínos , Doenças dos Suínos/epidemiologia
12.
PLoS One ; 12(12): e0188179, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29267290

RESUMO

Bacillus subtilis subsp. krictiensis ATCC55079 produces the cyclic lipopeptide antibiotics iturin A-F as well as several surfactins. Here, we analyzed and characterized the biosynthetic genes associated with iturin and surfactin production in this strain. We aligned the sequences of each iturin and surfactin synthetase ORF obtained from a genomic library screen and next generation sequencing. The resulting 37,249-bp and 37,645-bp sequences associated with iturin and surfactin production, respectively, contained several ORFs that are predicted to encode proteins involved in iturin and surfactin biosynthesis. These ORFs showed higher sequence homologies with the respective iturin and surfactin synthetase genes of B. methylotrophicus CAU B946 than with those of B. subtilis RB14 and B. subtilis ATCC6633. Moreover, comparative analysis of the secondary metabolites produced by the wild-type and surfactin-less mutant (with a spectinomycin resistance cassette inserted into the srfAB gene within the putative surfactin gene region) strains demonstrated that the mutant strain showed significantly higher antifungal activity against Fusarium oxysporum than the wild-type strain. In addition, the wild-type strain-specific surfactin high performance liquid chromatography (HPLC) peaks were not observed in the surfactin-less mutant strain. In contrast, the iturin A peak detected by HPLC and liquid chromatography-mass spectrometry (LC/MS) in the surfactin-less mutant strain was 30% greater than that in the wild-type strain. These results suggested that the gene cluster we identified is involved in surfactin biosynthesis, and the biosynthetic pathways for iturin and surfactin in Bacillus strains producing both iturin and surfactin may utilize a common pathway.


Assuntos
Bacillus subtilis/genética , Genes Bacterianos , Peptídeos Cíclicos/biossíntese , Bacillus subtilis/enzimologia , Cromatografia Líquida de Alta Pressão , Clonagem Molecular , Espectrometria de Massas , Fases de Leitura Aberta
13.
J Microbiol Biotechnol ; 27(7): 1272-1275, 2017 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-28535608

RESUMO

Two dimeric sesquiterpenes were separated from Chloranthus japonicus Sieb. and identified as shizukaols C and F. They exhibited potent antifungal activities (MICs = 4-16 µg/ml) in vitro against various plant pathogenic fungi (Pythium ultimum, Phytophthora infestans, Botrytis cinerea, Colletotrichum lagenarium, Alternaria kikuchiana, and Magnaporthe grisea). Shizukaol C showed 88% and 91% protective activities in the greenhouse against Puccinia recondita (wheat leaf rust) and Phytophthora infestans (tomato late blight), respectively, at 100 µg/ml; shizukaol F exhibited 93% antifungal activity against Puccinia recondita at the same concentration. Therefore, these compounds might serve as interesting candidates for effective antifungal agents.


Assuntos
Antifúngicos/farmacologia , Fungos/efeitos dos fármacos , Magnoliopsida/química , Sesquiterpenos/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Fungicidas Industriais/isolamento & purificação , Fungicidas Industriais/farmacologia , Medicina Tradicional Chinesa , Testes de Sensibilidade Microbiana , Phytophthora infestans/efeitos dos fármacos , Doenças das Plantas/prevenção & controle , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação
14.
Exp Mol Med ; 38(5): 525-34, 2006 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-17079869

RESUMO

Catechins, components of green tea, reduce the incidence of cardiovascular diseases such as atherosclerosis. Angiotensin II (Ang II) is highly implicated in the proliferation of vascular smooth muscle cells (VSMC), resulting in atherosclerosis. The acting mechanisms of the catechins remain to be defined in the proliferation of VSMC induced by Ang II. Here we report that catechin, epicatechin (EC), epicatechingallate (ECG) or epigallocatechingallate (EGCG) significantly inhibits the Ang II-induced [3H]thymidine incorporation into the primary cultured rat aortic VSMC. Ang II increases the phosphorylation of the extracellular signal-regulated protein kinase 1/2 (ERK 1/2), c-jun-N-terminal kinase 1/2 (JNK 1/2), or p38 mitogen-activated protein kinases (MAPKs) and mRNA expression of c-jun and c-fos. The EGCG pretreatment inhibits the Ang II-induced phosphorylation of ERK 1/2, JNK 1/2, or p38 MAPK, and the expression of c-jun or c-fos mRNA. U0126, a MEK inhibitor, SP600125, a JNK inhibitor, or SB203580, a p38 inhibitor, attenuates the Ang II-induced [3H]thymidine incorporation into the VSMC. In conclusion, catechins inhibit the Ang II-stimulated VSMC proliferation via the inhibition of the Ang II-stimulated activation of MAPK and activator protein-1 signaling pathways. The antiproliferative effect of catechins may be associated with the reduced risk of cardiovascular diseases by the intake of green tea. Catechins may be useful in the development of prevention and therapeutics of vascular diseases.


Assuntos
Angiotensina II/farmacologia , Catequina/farmacologia , Proliferação de Células/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Animais , Catequina/análogos & derivados , Catequina/fisiologia , Técnicas de Cultura de Células , Células Cultivadas , DNA/biossíntese , Feminino , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Músculo Liso Vascular/citologia , Inibidores da Síntese de Ácido Nucleico/farmacologia , Fosforilação , Proteínas Proto-Oncogênicas c-fos/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
15.
World J Gastroenterol ; 12(30): 4850-8, 2006 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-16937467

RESUMO

AIM: To investigate whether, or how, DA-9601, which is a new gastroprotective agent, inhibits TNF-alpha-induced inflammatory signals in gastric epithelial AGS cells. METHODS: Cell viability was determined by MTT assay. IL-8 and CCL20 promoter activities were determined by a luciferase reporter gene assay. NF-kappaB-dependent transcriptional activity was determined by I-kappaB alpha degradation, NF-kappaB p65 nuclear translocation and a luciferase activity assay. IL-8 and CCL20 gene expression and protein secretion were determined by RT-PCR and an enzyme-linked immunosorbent assay (ELISA). Total and phosphorylated forms of mitogen-activated protein kinases (MAPKs) were determined by Western blot. RESULTS: Treatment of AGS cells with DA-9601 reduced TNF-alpha-induced IL-8 and CCL20 promoter activities, as well as their gene expression and protein release. TNF-alpha also induced NF-kappaB-dependent transcriptional activity in AGS cells. In contrast, in cells treated with DA-9601, TNF-alpha-induced NF-kappaB activity was significantly blocked. Although all three MAP kinase family members were phosphorylated in response to TNF-alpha, a selective inhibitor of p38 kinase SB203580 only could inhibit both NF-kappaB-dependent transcriptional activity and IL-8 and CCL20 production, suggesting a potential link between p38 kinase and NF-kappaB-dependent pathways in AGS cells. Interestingly, DA-9601 also selectively inhibited p38 kinase phosphorylation induced by TNF-alpha. CONCLUSION: DA-9601 blocked TNF-alpha-mediated inflammatory signals by potentially modulating the p38 kinase pathway and/or a signal leading to NF-kappaB-dependent pathways in gastric epithelial cells.


Assuntos
Quimiocinas CC/metabolismo , Células Epiteliais/metabolismo , Interleucina-8/metabolismo , Proteínas Inflamatórias de Macrófagos/metabolismo , NF-kappa B/antagonistas & inibidores , Extratos Vegetais/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Artemisia/química , Quimiocina CCL20 , Quimiocinas CC/genética , Inibidores Enzimáticos/metabolismo , Células Epiteliais/citologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Mucosa Gástrica/citologia , Genes Reporter , Humanos , Interleucina-8/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Proteínas Inflamatórias de Macrófagos/genética , NF-kappa B/metabolismo , Extratos Vegetais/química , Regiões Promotoras Genéticas , Transdução de Sinais/fisiologia , Transcrição Gênica , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
16.
Naunyn Schmiedebergs Arch Pharmacol ; 371(2): 152-7, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15692818

RESUMO

It is now well known that 17beta-estradiol has an endothelium-independent, non-genomic vasorelaxant effect. We hypothesized that 17beta-estradiol has its non-genomic effect on calcium-independent contraction in de-endothelialized rat aortic rings. Rat aortic ring preparations were mounted in organ baths and exposed to contractile agents. 17beta-Estradiol (8, 20 or 50 microM), but not 17alpha-estradiol, concentration-dependently decreased the tension induced by 1.0 microM phenylephrine (PE) in the presence, but not in the absence, of calcium in the solution. Pretreatment with 17beta-estradiol concentration-dependently inhibited vascular contractions induced by cumulative addition of PE or calcium and almost completely abolished those induced by cumulative addition of Bay K8644, a calcium channel opener. Furthermore, 17beta-estradiol also concentration-dependently decreased the tension induced by 0.3 microM phorbol 12,13-dibutyrate (PDBu), a protein kinase C activator, in the presence of calcium in the solution, but not in the absence of calcium in the solution. Pretreatment with 17beta-estradiol had little effect on vascular contractions induced by PDBu or PE or on PE-induced mitogen-activated protein kinase (MAPK) activation in calcium-free Krebs solution. These results suggest that 17beta-estradiol inhibits calcium-dependent, but not calcium-independent, vascular contraction.


Assuntos
Cálcio/farmacologia , Estradiol/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Vasoconstrição/efeitos dos fármacos , Vasoconstritores/farmacologia , Éster Metílico do Ácido 3-Piridinacarboxílico, 1,4-Di-Hidro-2,6-Dimetil-5-Nitro-4-(2-(Trifluormetil)fenil)/farmacologia , Animais , Agonistas dos Canais de Cálcio/farmacologia , Interações Medicamentosas , Fenilefrina/farmacologia , Ratos , Ratos Sprague-Dawley
17.
Exp Mol Med ; 35(6): 467-74, 2003 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-14749523

RESUMO

Resveratrol has been shown to possess antioxidant and anticancer activities, but little is known on the effect of resveratrol derivatives. Recently we have isolated resveratrol and its dimers and trimers from peony (Paeonia lactiflora) seeds, and reported their strong antioxidant and cytotoxic activity. In the present study, we have evaluated cellular effects of resveratrol derivatives; viniferin, gnetin H, and suffruticosol B on the proliferation and apoptosis in HL-60 cells in vitro. All resveratrol and its derivatives reduced viability of HL-60 cells in a dose-dependent manner with their IC(50) values of 20-90 microM. Ascending orders of IC(50) values were suffruticosol B, gnetin H, viniferin and resveratrol respectively. HL-60 cells treated with the four stilbenes exhibited the distinct morphological changes characteristics of cell apoptosis such as chromatin condensation, apoptotic bodies, and DNA fragmentations. A time-dependent histogram of the cellular DNA analyzed by flow cytometry revealed a rapid increase in subdiploid cells and a concomitant decrease in diploid cells exposed to 100 microM resveratrol for 0-24 h. Cells treated with 25 microM of resveratrol, viniferin, gnetin H, and suffruticosol B for 24 h resulted in increment of sub-G1 population by 51, 5, 11 and 59%, respectively. Treatment of cells with 0-20 microM resveratrol for 5 h produced a concentration-dependent decrease in cytochrome P450 (CYP) 1B1 mRNA levels. Suffruticosol B also suppressed CYP1B1 gene expression. These results demonstrated that resveratrol oligomers also strongly suppressed HL-60 cell proliferation, and induced DNA damage. In addition, CYP1B1 gene supression may suggest an involvement in the resveratrol-induced apoptosis in HL-60 cells.


Assuntos
Apoptose/efeitos dos fármacos , Leucemia/patologia , Estilbenos/química , Estilbenos/farmacologia , Hidrocarboneto de Aril Hidroxilases , Ciclo Celular/efeitos dos fármacos , Citocromo P-450 CYP1B1 , Sistema Enzimático do Citocromo P-450/genética , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HL-60 , Humanos , Leucemia/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Resveratrol , Estilbenos/toxicidade
18.
Arch Pharm Res ; 26(8): 620-30, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12967197

RESUMO

The proliferative effects of thirty Oriental medicinal herbs on MCF-7 (estrogen-sensitive breast cancer cell line) and ROS 17/2.8 osteoblast-like cells were determined using the MTT assay. Methanol extracts from several herbs was found to show proliferative activity on the above two cell lines in the range of 5 to 100 microg/mL. Among these active herbs, the methanol extract from the rhizomes of Drynaria fortunei showed the most potent proliferative activity, and the cell proliferations were significantly increase by 136 and 158% in the MCF-7 and ROS 17/2.8 cells, respectively, when treated with 100 microg/mL. Through a bioassay-guided separation, eight flavonoids, including four new flavan-3-ols and two propelargonidins, together with the known (-)-epiafzelechin and naringin, were isolated. Their chemical structures were characterized as (-)-epiafzelechin (1), (-)-epiafzelechin-3-O-beta-D-allopyranoside (2), (-)-epiafzelechin-3-O-(6"-O-acetyl)-beta-D-allopyranoside (3), 4beta-carboxymethyl-(-)-epiafzelechin methyl ester (4), 4beta-carboxymethyl-(-)-epiafzelechin sodium salt (5), naringin (6), (-)-epiafzelechin-(4beta-->8)-4beta-carboxymethylepiafzelechin methyl ester (7) and (-)epiafzelechin-(4beta-->8, 2beta-->O-->7)-epiafzelechin-(4beta-->8)-epiafzelechin (8) by extensive 1D and 2D NMR spectroscopy. Most of these flavonoids, in the range of 10(-15) to approximately 10(-6) M, accelerated the proliferation of MCF-7 cell, with compounds 7 and 8, in the range of 10(-15) to approximately 10(-12) M, showing especially potent proliferation effects. Meanwhile, seven flavonoids, with the exception of compound 4, stimulated the proliferation of ROS 17/2.8 cells in the range of 10(-15) to approximately 10(-6) M, with compounds 5-8 especially accelerating the proliferation, in dose-dependent manners (10(-15) to approximately 10(-9) M), and their proliferative effect was much stronger than that of E2 and genistein. These results suggest that propelargonidin dimers and trimers isolated from the rhizomes of Drynaria fortunei may be useful as potential phytoestrogens, which play important physiological roles in the prevention of postmenopausal osteoporosis.


Assuntos
Flavonoides/farmacologia , Isoflavonas/farmacologia , Preparações de Plantas/farmacologia , Polypodiaceae/química , Animais , Neoplasias da Mama/patologia , Divisão Celular/efeitos dos fármacos , Medicamentos de Ervas Chinesas/química , Flavonoides/isolamento & purificação , Humanos , Isoflavonas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Osteoblastoma/patologia , Osteoporose Pós-Menopausa/prevenção & controle , Fitoestrógenos , Preparações de Plantas/isolamento & purificação , Ratos , Rizoma/química , Células Tumorais Cultivadas
19.
J Nutr Sci Vitaminol (Tokyo) ; 50(1): 32-7, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15228215

RESUMO

Six polyphenolic compounds were isolated from ethylacetate extract secondary to 80% ethanol extraction of defatted safflower seeds. They were categorized into three types: lignans, flavones and serotonin derivatives. Female Sprague-Dawley rats weighing 163.4 +/- 6.3 g were ovariectomized (Ovx) and fed either ethylacetate extract at a level of 1% (w/w) or three types of safflower polyphenolic compounds at a level of 200 mg/kg in a diet containing 0.5% (w/w) cholesterol for four wk. The sham and Ovx control groups were fed the same diet without safflower components. Plasma GOT and GPT levels did not differ among the six experimental groups. The plasma levels of total cholesterol were reduced in the four safflower groups by 20-30% as compared to the Ovx control. The plasma level of HDL-cholesterol was higher in the Ovx+ethylacetate extract group or appeared to be in the three Ovx+safflower polyphenolic groups than in the Ovx control. The level of plasma triglyceride was also significantly lower in the Ovx+lignan group than in the Ovx control. The liver level of cholesterol was significantly reduced in the Ovx+ethylacetate extract group. Fecal excretion of cholesterol increased by the safflower lignans and flavones, whereas that of bile acid was not significantly changed by the safflower polyphenols. Matairesinol and acacetin isolated from safflower seeds reduced the cholesterol content in cultured HepG2 cells at a concentration of 0.01-0.1 microM and all three safflower polyphenolics decreased triglyceride content at the concentration of 0.1 microM. These results suggest that safflower polyphenols have the effect of improving blood lipid status via increasing HDL-cholesterol formation and cholesterol excretion without significant uterotropic action in estrogen-deficient animals.


Assuntos
Carthamus tinctorius/química , Colesterol na Dieta/administração & dosagem , Lipídeos/análise , Fígado/química , Fenóis/administração & dosagem , Sementes/química , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Ácidos e Sais Biliares/análise , Peso Corporal , Linhagem Celular , Colesterol/análise , Colesterol/sangue , Dieta , Fezes/química , Feminino , Flavonoides/administração & dosagem , Lipídeos/sangue , Tamanho do Órgão , Ovariectomia , Extratos Vegetais/administração & dosagem , Ratos , Ratos Sprague-Dawley , Triglicerídeos/análise , Triglicerídeos/sangue
20.
J Vet Sci ; 14(4): 467-72, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24421718

RESUMO

Swine hepatitis E virus (HEV) is widespread throughout pigs in both developing and industrialized countries. This virus is an important zoonotic agent and a public concern worldwide. Infected pigs are asymptomatic, so diagnosing swine HEV relies on detection of the virus or antibodies against the virus. However, several obstacles need to be overcome for effective and practical serological diagnosis. In this study, we developed an enzyme-linked immunosorbent assay (ELISA) that used a purified recombinant capsid protein of swine HEV. The potential clinical use of this assay was evaluated by comparing it with a commercial kit (Genelabs Technologies, Diagnostics, Singapore). Results of the ELISA were highly correlated with those of the commercial kit with a sensitivity of 97% and specificity of 95%. ROC (receiving operator characteristic) analysis of the ELISA data produced a value of 0.987 (95% CI, 0.977~0.998, p < 0.01). The cut-off value for the ELISA was also determined using negative pig sera. In summary, the HEV-specific ELISA developed in the present study appears to be both practical and economical.


Assuntos
Anticorpos Anti-Idiotípicos/análise , Proteínas do Capsídeo/genética , Ensaio de Imunoadsorção Enzimática/métodos , Vírus da Hepatite E/isolamento & purificação , Hepatite E/veterinária , Doenças dos Suínos/diagnóstico , Animais , Anticorpos Anti-Idiotípicos/sangue , Anticorpos Anti-Idiotípicos/genética , Proteínas do Capsídeo/metabolismo , Ensaio de Imunoadsorção Enzimática/veterinária , Hepatite E/diagnóstico , Hepatite E/imunologia , Hepatite E/virologia , Vírus da Hepatite E/genética , Vírus da Hepatite E/metabolismo , Imunoglobulina G/sangue , Imunoglobulina G/genética , Curva ROC , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/virologia
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