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We used the job-demand-control model to answer our two research questions concerning the effects of working conditions on self-rated health and gender differences and the association between these working conditions and health among Korean manual workers. Since a disproportionate representation of women in nonstandard work positions is found in many countries, including Korea, it is important to examine how working conditions explain gender inequality in health. We used data from the 2008-2009 Korean National Health and Nutrition Examination Survey and analyzed a total sample of 1,482 men and 1,350 women using logistic regression. We found that job control was positively related to self-rated health, while both physical and mental job demands were negatively related to self-rated health. We also found significant interaction effects of job demands, control, and gender on health. Particularly, female workers' health was more vulnerable to mentally demanding job conditions. We discussed theoretical and practice implications based on these findings.
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Emprego/psicologia , Nível de Saúde , Fatores Sexuais , Estresse Psicológico/complicações , Carga de Trabalho/psicologia , Local de Trabalho/normas , Adolescente , Adulto , Idoso , Família , Feminino , Inquéritos Epidemiológicos , Humanos , Satisfação no Emprego , Masculino , Saúde Mental , Pessoa de Meia-Idade , Saúde Ocupacional , República da Coreia , Distribuição por Sexo , Fatores Socioeconômicos , Adulto JovemRESUMO
The behavior and fate of intravenously (i.v.) injected nanoparticles (NPs) can be controlled by several physicochemical factors including size, shape and surface charge. To evaluate the role of surface charge on distribution of NPs, we used neutral-charged 15-nm-sized polyethylene glycol-coated gold nanoparticles (AuNP(PEG)) as a core NP and carboxyl or amine groups were conjugated to AuNP(PEG) to generate negative (AuNP(COOH)) or positive AuNP (AuNP(NH2)), respectively. Each type of AuNP was i.v. injected into mice (1 mg kg(-1)) and the concentration of Au was measured in different organs at 30 min, 4, 24 h, 7, 14 days, 1, 3 and 6 months post-injection. The organ distribution also showed the higher deposition rate depending on their functional groups: AuNP(PEG) for mesenteric lymph node, kidney, brain and testis; AuNP(COOH) for liver; AuNP(NH2) for spleen, lung and heart. The blood circulation time and the major excretion route were different depending on their functional groups. In conclusion, functional groups conjugated on the surface of AuNPs produce differences in blood kinetics, organ distribution and elimination pattern which can be important information for directing NPs to specific organs or improving the kinetic properties.
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Compostos de Ouro/farmacocinética , Nanopartículas Metálicas/efeitos adversos , Animais , Compostos de Ouro/efeitos adversos , Compostos de Ouro/análise , Injeções Intravenosas , Masculino , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/análise , Camundongos , Camundongos Endogâmicos BALB C , Espectrofotometria Atômica/métodos , Propriedades de Superfície , Distribuição TecidualRESUMO
[Purpose] The present study attempted to identify the effect of olfactory stimulation on the balance ability of stroke patients. [Subjects] Thirty-three (33 males) stroke patients participated in the study. The stroke patients were divided into three groups: a black pepper oil (BPO) group (n=11), lavender oil (LVO) group (n=11), and distilled water (DW) group (n=11). [Methods] Two sessions (control trial/stimulus trial) of Romberg's test (eyes open 1â min/eyes closed 1â min) were conducted on a force platform to measure the data for the COP (center of pressure). Olfactory stimulation was provided at as a stimulus. [Results] With the eyes open, a statistically significant difference was found in average anterior posterior displacement (Ymean) and average medial lateral displacement (Xmean) among the three groups when comparing the groups before and after stimulation. The comparison between the eyes open and eyes closed conditions in each group showed a significant difference in the area of the 95% confidence ellipse (area) and Xmean of the BPO group and in the area of the LVO group (area, Xmean). [Conclusion] The findings indicate that the interaction of brain areas activated by the olfactory stimulation exerts an influence on the balance ability of stroke patients.
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Resveratrol is a phytoalexin abundantly found in red grape skin and is effective in antitumor and antiinflammation associated with immune responses. This study investigated whether resveratrol suppressed immunoglobulin (Ig)E-mediated allergic responses and passive cutaneous anaphylaxis (PCA) in rat RBL-2H3 mast cells and in BALB/c mice. The release of ß-hexosaminidase and histamine was enhanced in mast cells sensitized with anti-dinitrophenyl (DNP)-IgE and subsequently stimulated by DNP-human serum albumin (HSA), indicative of mast cell degranulation. When mast cells were pretreated with nontoxic resveratrol at 1-25 µmol/L, such induction was dose dependently diminished. Spleen tyrosine kinase (Syk) and phospholipase Cγ (PLCγ) of sensitized mast cells were activated by stimulation with DNP-HSA antigen, which was dampened by ≥5 µmol/L resveratrol. The phosphorylation of protein kinase C (PKC)µ and PKCθ was attenuated by administering resveratrol to DNP-HSA-exposed mast cells, whereas quiescent PKCζ/λ in sensitized cells was dose-dependently activated by resveratrol. Male BALB/c mice were sensitized for 24 h with DNP-IgE and orally administered with resveratrol 1 h before the DNP-HSA challenge. The histamine concentration was enhanced in sensitized mice challenged to DNP-HSA, which was reversed by administration of 10 mg/kg resveratrol. Additionally, it encumbered the tissue activation of Syk, PLCγ, and PKCµ in antigen-exposed mice. Resveratrol decreased IgE-mediated PCA and alleviated allergic edema of mouse ear and dorsal skin. Mast cell degranulation and allergic inflammation, accompanying the induction of monocyte chemotactic protein-1 and macrophage inflammatory protein-2, were inhibited by supplementing resveratrol to antigen-challenged mice. Resveratrol inhibited mast cell-derived, immediate-type allergic reactions, and these responses of resveratrol suggest possible therapeutic strategies in preventing allergic inflammatory diseases.
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Anafilaxia/prevenção & controle , Liberação de Histamina/efeitos dos fármacos , Imunoglobulina E/metabolismo , Mastócitos/efeitos dos fármacos , Fitoterapia , Pele/efeitos dos fármacos , Estilbenos/uso terapêutico , Anafilaxia/imunologia , Anafilaxia/metabolismo , Animais , Basófilos , Antígeno CD24/metabolismo , Quimiocina CCL2/metabolismo , Quimiocina CXCL2/metabolismo , Suplementos Nutricionais , Dinitrofenóis , Relação Dose-Resposta a Droga , Edema/imunologia , Edema/prevenção & controle , Histamina/metabolismo , Inflamação/prevenção & controle , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Mastócitos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Anafilaxia Cutânea Passiva , Fosfolipase C gama/metabolismo , Fosforilação , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Proteínas Tirosina Quinases/metabolismo , Ratos , Resveratrol , Albumina Sérica , Pele/imunologia , Pele/metabolismo , Estilbenos/farmacologia , Quinase Syk , Vitis/química , beta-N-Acetil-Hexosaminidases/metabolismoRESUMO
Atomic nitrogen doping on CeO2 nanoparticles (NPs) by an efficient and environmentally benign urea thermolysis approach is first studied, and its effects on the intrinsic scavenging activity of the CeO2 NPs for reactive oxygen radicals are investigated. The N-doped CeO2 (N-CeO2) NPs, characterized by X-ray photoelectron and Raman spectroscopy analyses, showed considerably high levels of N atomic doping (2.3-11.6%), accompanying with an order of magnitude increase of the lattice oxygen vacancies on the CeO2 crystal surface. The radical scavenging properties of the N-CeO2 NPs are characterized by applying Fenton's reaction with collective and quantitative kinetic analysis. The results revealed that the significant increase of surface oxygen vacancies is the leading cause for the enhancements of radical scavenging properties by the N doping of CeO2 NPs. Enriched with abundant surface oxygen vacancies, the N-CeO2 NPs prepared by urea thermolysis provided about 1.4-2.5 times greater radical scavenging properties than the pristine CeO2. The collective kinetic analysis revealed that the surface-area-normalized intrinsic radical scavenging activity of the N-CeO2 NPs is about 6- to 8-fold greater than that of the pristine CeO2 NPs. The results suggest the high effectiveness of the N doping of CeO2 by the environmentally benign urea thermolysis approach to enhance the radical scavenging activity of CeO2 NPs for extensive applications such as that in polymer electrolyte membrane fuel cells.
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Ellagic acid, a polyphenol compound present in berries and pomegranate, has received attention as an agent that may have potential bioactivities preventing chronic diseases. This study examined photoprotective effects of ellagic acid on collagen breakdown and inflammatory responses in UV (ultraviolet)-B irradiated human skin cells and hairless mice. Ellagic acid attenuated the UV-B-induced toxicity of HaCaT keratinocytes and human dermal fibroblasts. Non-toxic ellagic acid markedly prevented collagen degradation by blocking matrix metalloproteinase production in UV-B-exposed fibroblasts. Anti-wrinkle activity of ellagic acid was further investigated in hairless mice exposed to UV-B, in which it attenuated UV-B-triggered skin wrinkle formation and epidermal thickening. Topical application of 10 micromol/l ellagic acid diminished production of pro-inflammatory cytokines IL-1beta and IL-6, and blocked infiltration of inflammatory macrophages in the integuments of SKH-1 hairless mice exposed to UV-B for 8 weeks. In addition, this compound mitigated inflammatory intracellular cell adhesion molecule-1 expression in UV-B-irradiated keratinocytes and photoaged mouse epidermis. These results demonstrate that ellagic acid prevented collagen destruction and inflammatory responses caused by UV-B. Therefore, dietary and pharmacological interventions with berries rich in ellagic acid may be promising treatment strategies interrupting skin wrinkle and inflammation associated with chronic UV exposure leading to photoageing.
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Dermatite/tratamento farmacológico , Ácido Elágico/farmacologia , Ácido Elágico/uso terapêutico , Envelhecimento da Pele/efeitos dos fármacos , Raios Ultravioleta/efeitos adversos , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Colágeno/metabolismo , Dermatite/etiologia , Dermatite/patologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Queratinócitos/efeitos da radiação , Masculino , Metaloproteinases da Matriz/metabolismo , Camundongos , Camundongos Pelados , Modelos Animais , Envelhecimento da Pele/patologia , Envelhecimento da Pele/efeitos da radiação , Resultado do TratamentoRESUMO
UDP-glucose dehydrogenase (UGDH) is an enzyme catalyzing the conversion of UDP-glucose to UDP-glucuronic acid. Site-directed mutagenesis studies have revealed that human UGDH (hUGDH) has distinct oligomeric states that vary with different point mutations. In this study we have investigated how the changes in the oligomer-forming propensity may be involved in the thermal motion of wild-type hUGDH and its mutants, using normal mode analysis (NMA). Our results show that the perturbation caused by the mutation of a residue at a considerably distant location from the oligomeric interfaces is preferentially distributed throughout specific sites, especially the large flexible regions in the hUGDH structure, thereby changing the motional fluctuation pattern at the oligomeric interfaces. A large-magnitude cooperative motion at the oligomeric interfaces is a critical factor in interfering with the hexamer formation of the enzyme. In particular, structural stability at the dimeric interface is necessary to retain the hexameric structure of hUGDH.
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Uridina Difosfato Glucose Desidrogenase/química , Uridina Difosfato Glucose Desidrogenase/genética , Sequência de Aminoácidos , Cristalografia por Raios X , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Mutação Puntual , Estrutura Quaternária de Proteína , Subunidades Proteicas , Homologia de Sequência de Aminoácidos , TermodinâmicaRESUMO
BACKGROUND: There are insufficient data as to the influence of the head and neck flexion, extension, and rotation on the ventilation with laryngeal tube suction II (LTS II). The purpose of this study was to investigate the influence of the head and neck position on oropharyngeal sealing pressure (primary outcome) and ventilation score (secondary outcome) during ventilation with the LTS II in children. METHODS: We studied 33 children scheduled for elective surgery. Oropharyngeal sealing pressure and ventilation score were measured with the head and neck in a neutral position, flexed, extended and rotated to the right. The ventilation score was scored from 0 to 3 based on three items (no leakage with an airway pressure of 15 cmH2O, bilateral chest excursion, and a square wave capnogram; each item scored 0 or 1 point). Peak inspiratory pressure (PIP) at a tidal volume of 10 ml x kg(-1) and fiberoptic laryngeal views were also assessed in each position. RESULTS: Although the sealing pressure was lower in the extended position [22 (8) cmH2O] than that in the neutral position [25 (7) cmH2O], there was no significant leakage during ventilation with a tidal volume of 10 ml x kg(-1). In the neutral, extended and rotated positions, the median ventilation scores were better (3 point respectively) than that with the head and neck flexed (1 point). PIP was decreased with the head and neck extended or rotated but was significantly increased in flexion position. During fibreoptic examination, the vocal cords were more easily seen in extension and right rotation, compared with the neutral position and flexion. CONCLUSIONS: Although oropharyngeal sealing pressure is decreased with the head and neck extended, effective ventilation with LTS II can be performed like in the neutral position or the rotated position. While the sealing pressure is maintained with the head and neck flexed, flexion compromises the ventilation with LTS II in children.
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Cabeça , Máscaras Laríngeas/efeitos adversos , Postura/fisiologia , Respiração Artificial/instrumentação , Adolescente , Criança , Pré-Escolar , Procedimentos Cirúrgicos Eletivos , Desenho de Equipamento , Feminino , Humanos , Masculino , Pescoço , Pressão , Projetos de Pesquisa , Respiração Artificial/métodos , Sucção , Resultado do TratamentoRESUMO
Endothelial apoptosis is a driving force in atherosclerosis development. Oxidized LDL promotes inflammatory and thrombotic processes and is highly atherogenic, as it stimulates macrophage cholesterol accumulation and foam cell formation. This study investigated multiple mitogen-activated protein kinase (MAPK)-responsive death/survival signaling pathways, through which flavonoids of (-)epigallocatechin gallate (EGCG) and hesperetin exerted antiapoptosis in endothelial cells exposed to oxidized LDL. EGCG and hesperetin substantially diminished the oxidized LDL-induced 2',7'-dichlorofluorecein staining, suggesting that these flavonoids inhibited intracellular accumulation of oxidized LDL-triggered reactive oxygen species and consequent apoptosis. The Western-blot data revealed that oxidized LDL upregulated c-Jun N-terminal kinase (JNK) phosphorylation, which was rapidly reversed by EGCG and hesperetin. They mitigated the consequent activation of the JNK downstream on p53 and c-Jun. Moreover, oxidized LDL increased luciferase activity of p53 in endothelial cells transfected with a p53 promoter construct, the increase of which was strikingly downregulated by EGCG and hesperetin. Surprisingly, hesperetin but not EGCG attenuated phosphorylation of p38MAPK and its downstream c-myc and signal transducers and activators of transcription (STAT)1 evoked by oxidized LDL. This study also attempted to explore a linkage of Janus kinase (JAK)2/STAT3 activation to MAPK signaling in oxidized LDL-induced endothelial apoptosis. Notably, we found that the JAK2 inhibitor substantially blocked the JNK activation. Our findings suggest that EGCG and hesperetin may act as antiatherogenic agents blocking oxidized LDL-induced endothelial apoptosis via differential cellular apoptotic machinery. These data provide evidence that the interplay between p38MAPK and JAK-STAT pathways is involved in dietary flavonoid protection against oxidized LDL through hampering MAPK-dependent pathways involving the activation of JAK2.
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Células Endoteliais/efeitos dos fármacos , Flavonoides/farmacologia , Janus Quinases/metabolismo , Lipoproteínas LDL/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Fatores de Transcrição STAT/metabolismo , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Células Cultivadas , Humanos , Janus Quinases/antagonistas & inibidores , Transporte Proteico , Fatores de Transcrição STAT/antagonistas & inibidores , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismoRESUMO
Hyperglycemia is a causal factor in the development of diabetic vascular complications including impaired vascular smooth muscle contractility and increased cell proliferation. The present study was designed to investigate the effects of Sasa borealis water-extract (SBwE) on chronic hyperglycemia-induced oxidative stress and apoptosis in human umbilical endothelial cells (HUVEC). HUVEC were cultured in 5.5 mM low glucose, 5.5 mM glucose plus 27.5 mM mannitol as an osmotic control, or 33 mM high glucose for 5 days in the absence and presence of 1-30 microg/ ml SBwE. Caspase-3 activation and Annexin V staining revealed chronic high glucose-induced endothelial apoptotic toxicity with a generation of oxidants detected by DCF-fluorescence, and these effects were reversed by SBwE at > or =1 microg/ml in a dose-dependent manner. Cytoprotective SBwE substantially reduced the sustained high glucose-induced expression of endothelial nitric oxide synthase and attenuated the formation of peroxynitrite radicals. The suppressive effects of SBwE were most likely mediated through blunting activation of PKC beta 2 and NADPH oxidase promoted by high glucose. In addition, this bamboo extract modulated the high glucose-triggered mitogen-activated protein kinase-dependent upregulation of heat-shock proteins. Our results suggest that SBwE suppressed these detrimental effects caused by PKC-dependent peroxynitrite formation via activation of NADPH oxidase and induction of nitric oxide synthase and heat-shock protein family that may be essential mechanisms responsible for increased apoptotic oxidative stress in diabetic vascular complications. Moreover, the blockade of high glucose-elicited heat-shock protein induction appeared to be responsible for SBwE-alleviated endothelial apoptosis. Therefore, SBwE may be a therapeutic agent for the prevention and treatment of diabetic endothelial dysfunction and related complications.
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Apoptose/efeitos dos fármacos , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Glucose/farmacologia , Extratos Vegetais/farmacologia , Sasa/química , Células Cultivadas , Células Endoteliais/metabolismo , Proteínas de Choque Térmico/metabolismo , Humanos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NADPH Oxidases/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Ácido Peroxinitroso/biossíntese , Fitoterapia , Extratos Vegetais/química , Proteína Quinase C/metabolismo , Subunidades Proteicas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fatores de Tempo , Regulação para Cima/efeitos dos fármacosRESUMO
Ultraviolet (UV) irradiation leads to distinct changes in skin connective tissues by degradation of collagen, which is a major structural component in the extracellular matrix most likely mediated by matrix metalloproteinases (MMP), collagenases. These changes in collagenous skin tissues have been suggested to be causes of the skin wrinkling observed in premature aging of the skin. This study mimicked the action of environmental ultraviolet on skin and investigated whether (-)epigallocatechin gallate (EGCG), a bioactive catechin component of green tea, mechanistically inhibited activation of MMP-1, MMP-8, and MMP-13 and destruction of collagen in UV-B irradiated human dermal fibroblasts by modulating cellular signaling pathways. Cell viability was moderately decreased by > or = 30% in human dermal fibroblasts treated with 100 mJ/cm2 UV-B, accompanying a substantial generation of reactive oxygen species evidenced by DCF staining. Western blot analysis and immunocytochemical staining revealed that EGCG markedly suppressed collagen degradation enhanced in UV-B-exposed human dermal fibroblast. Pre-treatment of fibroblasts with EGCG also inhibited UV-B-induced production of collagenases, MMP-1, MMP-8 and MMP-13, in a dose-dependent manner. In addition, EGCG rapidly and substantially hampered UV-B irradiation-induced activation of ASK-1 and phosphorylation of MAPK, JNK, p38 MAPK, and ERK1/2, in dermal fibroblasts. These results demonstrate that EGCG has abilities to hamper UV-B-induced collagenolytic MMP production via interfering with the MAPK-responsive pathways. Therefore, EGCG may be a potential agent for the prevention and treatment of skin photoaging.
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Catequina/análogos & derivados , Colágeno/metabolismo , Colagenases/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Western Blotting , Catequina/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Eletroforese em Gel de Poliacrilamida , Ativação Enzimática/efeitos dos fármacos , Fibroblastos/efeitos da radiação , Humanos , Imuno-Histoquímica , Metaloproteinases da Matriz/biossíntese , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Espécies Reativas de Oxigênio , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/efeitos da radiação , Pele/citologia , Pele/efeitos dos fármacos , Pele/efeitos da radiação , Raios UltravioletaRESUMO
Coping is a strategic approach to dealing with stressful situations. Those who use proactive coping strategies tend to accept changes and act before changes are expected. In contrast, those who use reactive coping are less flexible and more likely to act in response to changes. However, little research has assessed how coping style changes with age. This study investigated age-related changes in coping strategies and stress responsiveness and the influence of age on the processing of conditioned fear memory in 2-, 12- and 23-month-old male mice. Coping strategy was measured by comparing the escape latency in an active avoidance test and by comparing responses to a shock prod. The results showed that proactivity in coping response gradually decreased with age. Stress responsiveness, measured by stress-induced concentration of corticosterone, was also highest in 2-month-old mice and decreased with age. Consolidation of fear memory was highest in 12-month-old mice and was negatively correlated with the degree of stress responsiveness and proactivity in coping. Fear extinction did not differ among age groups and was not correlated with stress responsiveness or the proactivity of coping. However, the maintenance of extinct fear memory, which was best in 2-month-old mice and worst in 12-month-old mice, was negatively correlated with stress responsiveness but not with coping style. Age-dependent changes in the expression of glucocorticoid receptor (GR) and its regulatory co-chaperones, which are accepted mechanisms for stress hormone stimulation, were measured in the hippocampus. The expression of GR was increased at 12 months compared to other age groups. There were no differences in Hsp70 and BAG1 expression by age. These results can be summarized as follows: (1) stress responsiveness and proactivity in coping decreased with age class; (2) consolidation of fear memory was negatively correlated with both stress responsiveness and proactivity; however, maintenance of extinct fear memory was negatively correlated with stress responsiveness only; and (3) consolidation and maintenance of extinct fear memory appeared to be more influenced by factors other than stress reactivity and proactivity in coping, such as the amount of hippocampal glucocorticoid expression.
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Numerous polyphenolic compounds have been found to inhibit adhesion and migration of leukocytes to sites of inflammation that are partly regulated by the expression of cell adhesion molecules (CAM) such as vascular cell adhesion molecule-1 (VCAM-1), E-selectin, and platelet endothelial cell adhesion molecule-1 (PECAM-1). Licorice root extracts have been used in traditional Chinese, Tibetan, and Indian medicine for the treatment of pulmonary diseases and inflammatory processes. Expression of CAM proteins was examined in human umbilical vein endothelial cells (HUVEC) treated with a licorice component (isoliquiritigenin, 18beta-glycyrrhetinic acid, glycyrrhizin, formononetin, or ononin) and exposed to TNF-alpha. The involvement of NF-kappaB in the transcriptional control of CAM proteins was assessed by degradation of IkappaBalpha and nuclear translocation of NF-kappaB using Western blotting techniques and immunocytochemical staining. At nontoxic > or =10 microM, isoliquiritigenin blocked the induction of VCAM-1 and E-selectin on activated HUVEC and markedly interfered with THP-1 monocyte adhesion to TNF-alpha-activated endothelial cells. Isoliquiritigenin abolished TNF-alpha-induced mRNA accumulation of VCAM-1 and E-selectin. Additionally, immunocytochemical staining revealed that isoliquiritigenin attenuated PECAM-1 expression induced by TNF-alpha. In contrast, other components recognized in licorice, 18beta-glycyrrhetinic acid, glycyrrhizin, formononetin, and ononin did not down-regulate the expression of VCAM-1 and/or PECAM-1 activated by TNF-alpha, implying that these components are inactive in modulating adhesion of leukocytes to stimulated endothelial cells. Isoliquiritigenin downregulated CAM proteins in TNF-alpha-activated HUVEC at the transcriptional levels by blocking degradation of IkappaBalpha and nuclear translocation of NF-kappaB. These results demonstrate that the induction blockade of VCAM-1 and E-selectin by isoliquiritigenin was directly mediated by its interference with the CAM mRNA transcription through NF-kappaB-dependent mechanisms under inflammatory conditions.
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Adesão Celular/efeitos dos fármacos , Chalconas/farmacologia , Citocinas/antagonistas & inibidores , Endotélio Vascular/efeitos dos fármacos , Glycyrrhiza/química , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sequência de Bases , Células Cultivadas , Primers do DNA , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Humanos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
Portable, non-toxic, and user-friendly sponge composites decorated with polyelectrolyte (PE) brushes were developed for the fast and efficient removal of heavy metal ions from waste water or drinking water. The polyacrylamide (PAM) and polyacrylic acid (PAA) brushes were grafted onto the sponge via "grafting-from" polymerization. For the polyethyleneimine (PEI) brush, "grafting-to" polymerization was used. A polydopamine (Pdop) layer was first coated on the sponge. Then, PEI was grafted onto the Pdop-coated sponge via a Michael addition reaction. The PEI-grafted sponge exhibited the best adsorption capacity and the fastest reaction rate of all the brushes due to the numerous adsorption sites of the PEI. The adsorption performance of two different PEI-grafted sponges depended on the molecular weight (MW) of the PEI. Simply by being dipped into a glass of water, non-toxic PEI-grafted sponge instantly removed the low concentration heavy metal ions, demonstrating a practical application for individual users.
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We present the synthesis of polydopamine particle-gold composites (PdopP-Au) and unique release of Au@Pdop core@shell nanoparticles (NPs) from the PdopP-Au upon external stimuli. The PdopP-Au was prepared by controlled synthesis of AuNPs on the Pdop particles. Upon near infrared (NIR) irradiation or NaBH4 treatment on the PdopP-Au, the synthesized AuNPs within the PdopPs could be burst-released as a form of Au@Pdop NPs. The PdopP-Au composite showed outstanding photothermal conversion ability under NIR irradiation due to the ultrahigh loading of the AuNPs within the PdopPs, leading to a remote-controlled explosion of the PdopP-Au and rapid formation of numerous Au@Pdop NPs. The release of the Au@Pdop NPs could be instantly stopped or re-started by off or reboot of NIR, respectively. The structure of the released Au@Pdop NPs is suitable for a catalyst or adsorbent, thus we demonstrated that the PdopP-Au composite exhibited excellent and sustained performances for environmental remediation due to its capability of the continuous production of fresh catalysts or adsorbents during the reuse.
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A numerical simulation model, which was based on the setting and heating reactions of the binder phase of phosphate-bonded investment compacts, was developed to compute the porosities of set and burnout compacts. Densities and concentrations of microsilica particles in dilute suspension were measured and input into the simulation model. Validity of the model was confirmed by experimental results, that is, colloidal silica suspensions were prepared using different silica concentrations and mixed with investment powders. Porosities of these set and burnout compacts were experimentally measured. Effects of these factors on the porosity of compacts were examined using the developed simulation model: liquid/powder (L/P) ratio, concentration of microsilica particles in colloidal silica suspension, and ratio of binder component (NH4H2PO4) in investment powder. It was concluded that numerical simulation is a viable tool for dental materials research.
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Revestimento para Fundição Odontológica/química , Teste de Materiais/métodos , Modelos Químicos , Análise Numérica Assistida por Computador , Fosfatos/química , Dióxido de Silício/química , Fenômenos Químicos , Técnicas de Química Sintética , Coloides/química , Simulação por Computador , Análise do Estresse Dentário , Temperatura Alta , Tamanho da Partícula , Permeabilidade , Porosidade , Pós/química , ÁguaRESUMO
Pericardial tamponade can lead to significant hemodynamic derangement including cardiac arrest. We experienced a case of pericardial tamponade in a patient with end-stage renal disease. Hemodynamic changes occurred by unexpectedly aggravated pericardial effusion during surgery for iatrogenic hemothorax. We quickly administered a large amount of fluids and blood products for massive bleeding and fluid deficit due to hemothorax. Pericardial effusion was worsened by massive fluid resuscitation, and thereby resulted in pericardial tamponade. Hemodynamic parameters improved just after pericardiocentesis, and the patient was transferred to the intensive care unit.
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BACKGROUND: Cold and dry gas mixtures during general anesthesia cause the impairment of cilliary function and hypothermia. Hypothermia and pulmonary complications are critical for the patients with major burn. We examined the effect of heated breathing circuit (HBC) about temperature and humidity with major burned patients. METHODS: Sixty patients with major burn over total body surface area 25% scheduled for escharectomy and skin graft were enrolled. We randomly assigned patients to receiving HBC (HBC group) or conventional breathing circuit (control group) during general anesthesia. The esophageal temperature of the patients and the temperature and the absolute humidity of the circuit were recorded every 15 min after endotracheal intubation up to 180 min. RESULTS: There was no significant difference of the core temperature between two groups during anesthesia. The relative humidity of HBC group was significantly greater compared to control group (98% vs. 48%, P < 0.01). In both groups, all measured temperatures were significantly lower than that after intubation. CONCLUSIONS: The use of HBC helped maintain airway humidity, however it did not have the effect to minimize a body temperature drop in major burns.
RESUMO
Extracellular superoxide dismutase (EC-SOD) is the only enzyme that removes superoxide radical in the extracellular space. The reduction of EC-SOD is linked to many diseases, suggesting that the protein may have therapeutic value. EC-SOD is reported to be insoluble and to make inclusion bodies when overexpressed in the cytoplasm of Escherichia coli. The refolding process has the advantage of high yield, but has the disadvantage of frequent aggregation or misfolding during purification. For the first time, this study shows that fusion with maltose-binding protein (MBP), N-utilization substance protein A, and protein disulfide isomerase enabled the soluble overexpression of EC-SOD in the cytoplasm of E. coli. MBP-tagged human EC-SOD (hEC-SOD) was purified by MBP affinity and anion exchange chromatography, and its identity was confirmed by MALDI-TOF MS analysis. The purified protein showed good enzyme activity in vitro; however, there was a difference in metal binding. When copper and zinc were incorporated into hEC-SOD before MBP tag cleavage, the enzymatic activity was higher than when the metal ions were bound to the purified protein after MBP tag cleavage. Therefore, the enzymatic activity of hEC-SOD is associated with metal incorporation and protein folding via disulfide bond.
Assuntos
Cobre/química , Dissulfetos/química , Escherichia coli/genética , Superóxido Dismutase/química , Zinco/química , Sequência de Aminoácidos , Cobre/metabolismo , Citoplasma/genética , Citoplasma/metabolismo , Dissulfetos/metabolismo , Escherichia coli/metabolismo , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Espaço Extracelular , Expressão Gênica , Humanos , Proteínas Ligantes de Maltose/química , Proteínas Ligantes de Maltose/genética , Proteínas Ligantes de Maltose/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Fatores de Alongamento de Peptídeos/química , Fatores de Alongamento de Peptídeos/genética , Fatores de Alongamento de Peptídeos/metabolismo , Isomerases de Dissulfetos de Proteínas/química , Isomerases de Dissulfetos de Proteínas/genética , Isomerases de Dissulfetos de Proteínas/metabolismo , Dobramento de Proteína , Estrutura Secundária de Proteína , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Solubilidade , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fatores de Elongação da Transcrição , Zinco/metabolismoRESUMO
Porosities of set and burnout compacts of phosphate-bonded investments were determined. A gas pycnometer was used to measure the volumes, and hence the densities, of fine powders and porous compacts. Porosities of set and burnout compacts were then obtained from these data for as-received powders and dry set compacts by a numerical simulation method, subsequently leading on to the estimated compositions of conventional and rapid-heating investments used in this study. Excess water content in the hardening investment compact was evaluated as a function of setting time elapsed from the start of mixing. Porosities were about 24-32% for set compacts and 43% for burnout compacts, which well agreed with the numerically computed results. It was concluded that the functional composition of investment powder needed to achieve the optimal porosity as well as process parameters such as water-powder (W/P) ratio and keeping time of mixed investment casting slurry before heat treatment could be determined using the numerical simulation method developed in this study.