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1.
J Pediatr Nurs ; 76: 124-131, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38382187

RESUMO

PURPOSE: The aim of this study was to explore college students' perceptions of human papillomavirus (HPV) infection and their thoughts on prevention measures. DESIGN AND METHODS: A qualitative descriptive design was used. The study adopted purposive sampling at two universities in northern Taiwan and one in central Taiwan. Twenty-six college students participated, and data saturation was reached. Content analysis was undertaken. RESULTS: Four main themes emerged from the data narratives: 1) having very little knowledge of HPV infection, 2) being concerned about outcomes of HPV infection, 3) taking measures to protect oneself, and 4) expecting to have HPV prevention resources. CONCLUSIONS: The results indicated that college students needed a more complete understanding of HPV and prevention methods to protect themselves from infection. Schools were an ideal place to provide adequate information on HPV prevention. PRACTICE IMPLICATIONS: The study suggested providing HPV-related information through school health centers and government health departments to resolve common questions and misunderstandings about HPV infection. Healthcare professionals should have a complete understanding of HPV-related knowledge in order to provide detailed information to young people.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Infecções por Papillomavirus , Pesquisa Qualitativa , Estudantes , Humanos , Taiwan , Feminino , Infecções por Papillomavirus/prevenção & controle , Estudantes/psicologia , Estudantes/estatística & dados numéricos , Masculino , Adulto Jovem , Universidades , Adulto , Adolescente , Vacinas contra Papillomavirus/administração & dosagem
2.
Comput Inform Nurs ; 40(7): 506-512, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35120371

RESUMO

The integration of mobile devices and nursing information systems has become a trend in modern clinical practice with various information and communication technologies available. Smartphones are gradually replacing notebooks in clinical practice as a medium for nursing information systems. Clinical nursing practicums are a necessary means for nursing students to foster their professional competence. In addition to professional skills, nursing students must also learn to apply information technologies in clinical settings. This study aimed to understand nursing students' behavioral intention toward nursing information smartphones and to further identify the factors influencing nursing students' behavioral intentions based on the technology acceptance model. A cross-sectional research design was used in this study. Eighty nursing students were recruited from a regional teaching hospital in Central Taiwan. The findings demonstrated that subjects' perceived ease of use and perceived usefulness of nursing information smartphones, as well as their attitude toward using and behavioral intention to use the smartphones, were positive, and they provided constructive feedback and suggestions to improve nursing information systems in hospitals. The findings can serve as a reference for hospitals and clinical training institutions seeking to integrate nursing information systems in clinical nursing education.


Assuntos
Bacharelado em Enfermagem , Estudantes de Enfermagem , Estudos Transversais , Humanos , Intenção , Smartphone , Inquéritos e Questionários , Tecnologia
3.
Brain Behav Immun ; 66: 230-243, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28690034

RESUMO

Neuroinflammation is a pathological hallmark and has been implicated in the pathogenesis of Japanese encephalitis. Although brain pericytes show regulatory effects on neuroinflammation, their involvement in Japanese encephalitis-associated neuroinflammation is not understood. Here, we demonstrated that brain microvascular pericytes could be an alternative cellular source for the induction and/or amplification of neuroinflammation caused by Japanese encephalitis virus (JEV) infection. Infection of cultured pericytes with JEV caused profound production of IL-6, RANTES, and prostaglandin E2 (PGE2). Mechanistic studies revealed that JEV infection elicited an elevation of the toll-like receptor 7 (TLR7)/MyD88 signaling axis, leading to the activation of NF-κB through IKK signaling and p65 phosphorylation as well as cAMP response element-binding protein (CREB) via phosphorylation. We further demonstrated that extracellular signal-regulated kinase (ERK) could be an alternative regulator in transducing signals to NF-κB, CREB, and cytosolic phospholipase A2 (cPLA2) through the phosphorylation mechanism. Released IL-6 and RANTES played an active role in the disruption of endothelial barrier integrity and leukocyte chemotaxis, respectively. cPLA2/PGE2 had a role in activating NF-κB and CREB DNA-binding activities and inflammatory cytokine transcription via the EP2/cAMP/PKA mechanism in an autocrine loop. These inflammatory responses and biochemical events were also detected in the brain of JEV-infected mice. The current findings suggest that pericytes might have pathological relevance in Japanese encephalitis-associated neuroinflammation through a TLR7-related mechanism. The consequences of pericyte activation are their ability to initiate and/or amplify inflammatory cytokine expression by which cellular function of endothelial cells and leukocytes are regulated in favor of CNS infiltration by leukocytes.


Assuntos
Encefalite Japonesa/genética , Encefalite Japonesa/metabolismo , Expressão Gênica , Mediadores da Inflamação/metabolismo , Pericitos/metabolismo , Pericitos/virologia , Animais , Linhagem Celular , Citocinas/metabolismo , Vírus da Encefalite Japonesa (Espécie) , Masculino , Camundongos Endogâmicos C57BL , Transdução de Sinais , Regulação para Cima
4.
Glia ; 63(11): 1915-1932, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25959931

RESUMO

Blood-brain barrier (BBB) characteristics are induced and maintained by crosstalk between brain microvascular endothelial cells and neighboring cells. Using in vitro cell models, we previously found that a bystander effect was a cause for Japanese encephalitis-associated endothelial barrier disruption. Brain astrocytes, which neighbor BBB endothelial cells, play roles in the maintenance of BBB integrity. By extending the scope of relevant studies, a potential mechanism has been shown that the activation of neighboring astrocytes could be a cause of disruption of endothelial barrier integrity during the course of Japanese encephalitis viral (JEV) infection. JEV-infected astrocytes were found to release biologically active molecules that activated ubiquitin proteasome, degraded zonula occludens-1 (ZO-1) and claudin-5, and disrupted endothelial barrier integrity in cultured brain microvascular endothelial cells. JEV infection caused astrocytes to release vascular endothelial growth factor (VEGF), interleukin-6 (IL-6), and matrix metalloproteinases (MMP-2/MMP-9). Our data demonstrated that VEGF and IL-6 released by JEV-infected astrocytes were critical for the proteasomal degradation of ZO-1 and the accompanying disruption of endothelial barrier integrity through the activation of Janus kinase-2 (Jak2)/signal transducer and activator of transcription-3 (STAT3) signaling as well as the induction of ubiquitin-protein ligase E3 component, n-recognin-1 (Ubr 1) in endothelial cells. MMP-induced endothelial barrier disruption was accompanied by MMP-mediated proteolytic degradation of claudin-5 and ubiquitin proteasome-mediated degradation of ZO-1 via extracellular VEGF release. Collectively, these data suggest that JEV infection could activate astrocytes and cause release of VEGF, IL-6, and MMP-2/MMP-9, thereby contributing, in a concerted action, to the induction of Japanese encephalitis-associated BBB breakdown. GLIA 2015;63:1915-1932.

5.
J Virol ; 88(2): 1150-61, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24198423

RESUMO

Though the compromised blood-brain barrier (BBB) is a pathological hallmark of Japanese encephalitis-associated neurological sequelae, the underlying mechanisms and the specific cell types involved are not understood. BBB characteristics are induced and maintained by cross talk between brain microvascular endothelial cells and neighboring elements of the neurovascular unit. In this study, we show a potential mechanism of disruption of endothelial barrier integrity during the course of Japanese encephalitis virus (JEV) infection through the activation of neighboring pericytes. We found that cultured brain pericytes were susceptible to JEV infection but were without signs of remarkable cytotoxicity. JEV-infected pericytes were found to release biologically active molecules which activated ubiquitin proteasome, degraded zonula occludens-1 (ZO-1), and disrupted endothelial barrier integrity in cultured brain microvascular endothelial cells. Infection of pericytes with JEV was found to elicit elevated production of interleukin-6 (IL-6), which contributed to the aforementioned endothelial changes. We further demonstrated that ubiquitin-protein ligase E3 component n-recognin-1 (Ubr 1) was a key upstream regulator which caused proteasomal degradation of ZO-1 downstream of IL-6 signaling. During JEV central nervous system trafficking, endothelial cells rather than pericytes are directly exposed to cell-free viruses in the peripheral bloodstream. Therefore, the results of this study suggest that subsequent to primary infection of endothelial cells, JEV infection of pericytes might contribute to the initiation and/or augmentation of Japanese encephalitis-associated BBB breakdown in concerted action with other unidentified barrier disrupting factors.


Assuntos
Barreira Hematoencefálica/virologia , Vírus da Encefalite Japonesa (Espécie)/fisiologia , Encefalite Japonesa/virologia , Células Endoteliais/virologia , Pericitos/virologia , Animais , Encefalite Japonesa/genética , Encefalite Japonesa/metabolismo , Células Endoteliais/metabolismo , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Camundongos , Pericitos/metabolismo , Proteólise , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Proteína da Zônula de Oclusão-1/genética , Proteína da Zônula de Oclusão-1/metabolismo
6.
J Appl Gerontol ; 43(10): 1419-1427, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38652874

RESUMO

Older age is associated with reduced social networks while social skill abilities are important assets for older people to cope with these situations. To better understand older people's social skill ability and important demographic correlates, the present cross-sectional survey research interviewed 1000 Taiwanese older volunteers from 73 community care centers. Findings of a mixed model indicated that education and serving area outweighed other demographic factors significantly correlated with older volunteers' social skill ability. Latent class analyses further identified different latent ability groups for different education (high vs. low) or serving-area (urban vs. suburban) older volunteers. Specifically, low-education or suburban volunteers were correlated with disadvantageous social skill profiles. Notably, the suburban eclectic ability group exhibited a skill pattern signifying the risk of loneliness. Overall, the findings called for further investigation into the relationship between older people's socioeconomic factors (e.g., education and serving area) and their social skill ability.


Assuntos
Habilidades Sociais , Voluntários , Humanos , Masculino , Feminino , Idoso , Estudos Transversais , Taiwan , Idoso de 80 Anos ou mais , Voluntários/psicologia , Fatores Socioeconômicos , Solidão/psicologia , Pessoa de Meia-Idade , Escolaridade
7.
Glia ; 60(3): 487-501, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22144112

RESUMO

The substantial activation of microglia in Japanese encephalitis virus (JEV)-induced Japanese encephalitis found in numerous studies demonstrates that the disease pathogenesis involves bystander damage caused by microglia-released mediators. Previously, we reported that microglia synthesized and secreted bioactive mediators with neurotoxic potential into the cultured supernatants in response to JEV infection. In this study, we found that the supernatants of JEV-infected microglia caused MK801-inhibitable neuronal damage in cultured neurons, indicating a potential excitotoxic mechanism. Infection with JEV was found to elicit the extracellular glutamate accumulation from microglia but not from neuron and astrocyte cultures. The glutaminase inhibitor 6-diazo-5-oxo-L-norleucine, cystine/glutamate antiporter inhibitor α-aminoadipic acid, and the gap junction inhibitor carbenoxolone reduced JEV infection-induced microglial glutamate release and neurotoxicity. We further demonstrated that tumor necrosis factor-alpha (TNF-α) was a key cytokine which stimulated extensive microglial glutamate release by up-regulating glutaminase expression via signals involving protein kinase C, cAMP responsive element-binding protein, and CAAT-enhancer-binding protein-beta. Although the elevated expression of excitatory amino acid transporter 1 and 2 was observed in JEV-infected cells, the glutamate uptake activity was significantly inhibited by TNF-α. The JEV infection-induced alterations, such as the extracellular glutamate release and glutamate-mediated excitoneurotoxicity, also occurred in neuron/glia cultures. Our findings support a potential link between neuroinflammation and the development of excitotoxic neuronal injury in Japanese encephalitis. The link between neuroinflammation and excitotoxic death may involve a mechanism in which TNF-α released by microglia plays a facilitory role in glutamate excitoneurotoxicity via up-regulation of glutamate synthesis and down-regulation of glutamate uptake.


Assuntos
Ácido Glutâmico/metabolismo , Neuroglia/metabolismo , Neuroglia/virologia , Transdução de Sinais/fisiologia , Fator de Necrose Tumoral alfa/metabolismo , Animais , Animais Recém-Nascidos , Cálcio/metabolismo , Comunicação Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Células Cultivadas , Córtex Cerebral/citologia , Meios de Cultivo Condicionados/farmacologia , Citocinas/metabolismo , Maleato de Dizocilpina/farmacologia , Ensaio de Desvio de Mobilidade Eletroforética , Vírus da Encefalite Japonesa (Espécie)/fisiologia , Inibidores Enzimáticos/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Regulação Viral da Expressão Gênica , Neuroglia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/genética
8.
J Neurochem ; 123(2): 250-61, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22845610

RESUMO

Currently, the underlying mechanisms and the specific cell types associated with Japanese encephalitis-associated leukocyte trafficking are not understood. Brain microvascular endothelial cells represent a functional barrier and could play key roles in leukocyte central nervous system trafficking. We found that cultured brain microvascular endothelial cells were susceptible to Japanese encephalitis virus (JEV) infection with limited amplification. This type of JEV infection had negligible effects on cell viability and barrier integrity. Instead, JEV-infected endothelial cells attracted more leukocytes adhesion onto surfaces and the supernatants promoted chemotaxis of leukocytes. Infection with JEV was found to elicit the elevated production of intercellular adhesion molecule-1, cytokine-induced neutrophil chemoattractant-1, and regulated-upon-activation normal T-cell expressed and secreted, contributing to the aforementioned leukocyte adhesion and chemotaxis. We further demonstrated that extracellular signal-regulated kinase was a key upstream regulator which stimulated extensive endothelial gene induction by up-regulating cytosolic phospholipase A2, NF-κB, and cAMP response element-binding protein via signals involving phosphorylation. These data suggest that JEV infection could activate brain microvascular endothelial cells and modify their characteristics without compromising the barrier integrity, making them favorable for the recruitment and adhesion of circulating leukocytes, thereby together with other unidentified barrier-disrupting mechanisms contributing to Japanese encephalitis and associated neuroinflammation.


Assuntos
Encéfalo/metabolismo , Movimento Celular/fisiologia , Quimiocina CCL5/biossíntese , Quimiocinas CXC/biossíntese , Encefalite Japonesa/metabolismo , Molécula 1 de Adesão Intercelular/biossíntese , Animais , Encéfalo/imunologia , Adesão Celular/fisiologia , Linhagem Celular , Células Cultivadas , Quimiocinas/biossíntese , Quimiotaxia de Leucócito/fisiologia , Cricetinae , Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa/imunologia , Endotélio Vascular/imunologia , Endotélio Vascular/metabolismo , Feminino , Regulação Viral da Expressão Gênica , Leucócitos Mononucleares , Masculino , Microcirculação/fisiologia , Proteínas Quinases Ativadas por Mitógeno , Ratos Sprague-Dawley
9.
J Gen Virol ; 91(Pt 4): 1028-37, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20007359

RESUMO

Japanese encephalitis is characterized by profound neuronal destruction/dysfunction and concomitant microgliosis/astrogliosis. Although substantial activation of glia is observed in Japanese encephalitis virus (JEV)-induced Japanese encephalitis, the inflammatory responses and consequences of astrocytes and microglial activation after JEV infection are not fully understood. In this study, infection of cultured neurons/glia with JEV caused neuronal death and glial activation, as evidenced by morphological transformation, increased cell proliferation and elevated tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6 and RANTES (regulated upon activation, normal T-cell expressed and secreted) production. Replication-competent JEV caused all glial responses and neurotoxicity. However, replication-incompetent JEV lost these abilities, except for the ability to change microglial morphology. The bystander damage caused by activated glia also contributed to JEV-associated neurotoxicity. Microglia underwent morphological changes, increased cell proliferation and elevated TNF-alpha, IL-1beta, IL-6 and RANTES expression in response to JEV infection. In contrast, IL-6 and RANTES expression, but no apparent morphological changes, proliferation or TNF-alpha/IL-1beta expression, was demonstrated in JEV-infected astrocytes. Supernatants of JEV-infected microglia, but not JEV-infected astrocytes, induced glial activation and triggered neuronal death. Antibody neutralization studies revealed that TNF-alpha and IL-1beta, but not RANTES or IL-6, released by activated microglia appeared to play roles in JEV-associated neurotoxicity. In conclusion, following JEV infection, neuronal death was accompanied by concomitant microgliosis and astrogliosis, and neurotoxic mediators released by JEV-activated microglia, rather than by JEV-activated astrocytes, had the ability to amplify the microglial response and cause neuronal death.


Assuntos
Astrócitos/fisiologia , Vírus da Encefalite Japonesa (Espécie)/patogenicidade , Microglia/fisiologia , Neurônios/patologia , Animais , Morte Celular , Células Cultivadas , Citocinas/biossíntese , DNA/biossíntese , Gliose , Mediadores da Inflamação/fisiologia , Ratos , Ratos Sprague-Dawley
10.
Fish Shellfish Immunol ; 26(1): 49-55, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18984057

RESUMO

Prophenoloxidase (proPO) is a melanin-synthesising enzyme that plays important roles in immune responses by crustaceans. Previously, we cloned and characterized proPO-I from white shrimp, Litopenaeus vannamei. In the present study, a novel prophenoloxidase-II (proPO-II) cDNA was also cloned from haemocytes of L. vannamei using oligonucleotide primers and reverse-transcriptase polymerase chain reaction (RT-PCR). Both 3'- and 5'-regions were isolated by the rapid amplification of complementary (c)DNA end (RACE) method. The 2504-bp cDNA contained an open reading frame (ORF) of 2073 bp, an 84-bp 5'-untranslated region, and a 347-bp 3'-untranslated region containing the poly A tail. The molecular mass of the deduced amino acid sequence (691 amino acids) was 78.8 kDa with an estimated pI of 6.07. It contains two putative tyrosinase copper-binding motifs and a conserved C-terminal region common to all known proPOs. Comparisons of the amino acid sequences showed that white shrimp proPO-II is more closely related to the proPO of other penaeids than to that of crayfish, lobsters, crab, or a freshwater prawn, and is the ancestor type of known penaeid proPOs. proPO-I and proPO-II messenger (m)RNAs of shrimp were located on different loci, and were constitutively expressed mainly in haemocytes. The transcriptional regulation of these two proPOs in shrimp at different molt stages, those administered dietary sodium alginate, and those challenged with Vibrio alginolyticus were surveyed. The results showed that the proPOs may be directly involved in the acute-phase immune defence, and proPO-II may contribute earlier to immune defence in shrimp injected with V. alginolyticus, and it may be regulated by ecdysone. However, a similar effect was found by stimulating proPO-I and proPO-II mRNA expression in shrimp fed a sodium alginate-containing diet. Results of this study provide a basis for developing a comprehensive understanding of expression/function relationships of individual proPOs in shrimp.


Assuntos
Alginatos/farmacologia , Catecol Oxidase/genética , Precursores Enzimáticos/genética , Regulação da Expressão Gênica , Vibrio alginolyticus/fisiologia , Sequência de Aminoácidos , Animais , Catecol Oxidase/química , Clonagem Molecular , Precursores Enzimáticos/química , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Regulação da Expressão Gênica/fisiologia , Ácido Glucurônico/farmacologia , Ácidos Hexurônicos/farmacologia , Dados de Sequência Molecular , Muda/imunologia , Penaeidae/enzimologia , Penaeidae/imunologia , Penaeidae/microbiologia , Filogenia , Alinhamento de Sequência
11.
Int J Biol Macromol ; 124: 368-376, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30471400

RESUMO

Rice hull polysaccharides (RHPS) have been reported to activate innate immunity in mice. This study investigated the effects of RHPS on natural killer (NK) cell-mediated cytotoxicity in vitro and the possible underlying anticancer mechanisms in vivo. The results showed that sustained exposure to RHPS increased NK-92MI cell-mediated cytotoxicity in a time- and concentration-dependent manner. In addition, RHPS upregulated the expression of Fas ligand, TNF-related apoptosis-inducing ligand, perforin, and granzyme B of NK-92MI cells and induced the secretion of IFN-γ and TNF-α. In the in vivo experiment, colon cancer CT26-bearing mice were used to investigate the effects of RHPS in cytotoxicity and anticancer. The results revealed that RHPS inhibited cancer weight and volume in CT26-bearing mice and significantly upregulated splenic cytotoxicity and NK-cell population. Moreover, RHPS treatment increased NK-cell infiltration in tumors. Thus, RHPS can enhance NK-cell activation in vivo and in vitro, thereby exhibiting anticancer activity.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias do Colo/tratamento farmacológico , Citotoxicidade Imunológica/efeitos dos fármacos , Galactanos/administração & dosagem , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Galactanos/química , Galactanos/isolamento & purificação , Regulação Neoplásica da Expressão Gênica , Humanos , Interferon gama/genética , Células Matadoras Naturais/efeitos dos fármacos , Camundongos , Oryza/química , Fator de Necrose Tumoral alfa/genética , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Dev Comp Immunol ; 32(12): 1422-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18639931

RESUMO

We have investigated the expression of clottable protein (CP) in gonad of tiger shrimp (Penaeus monodon) and extent of its phosphorylation. Polyclonal antibodies against purified CP were prepared from rabbit serum. Using this anti-CP antiserum, the temporal expression of CP in gonads of tiger shrimp was analyzed. It was found that the CP occurs only in mature ovaries but not in immature ovaries and testes. Results of RT-PCR confirmed that these tissues expressed low levels of CP mRNA transcripts. Upon eyestalk-ablation, the ovaries in female shrimps were induced to develop, and the CP expression levels in ovaries were traced chronically by RT-PCR analyses. The expression level peaked on day 3 with an increase of about 40 folds relative to the basal level and returned to normal level (as the control shrimp) at day 12. The shrimp embryos at different intervals from spawning to 16h post-spawning were also collected, and it was found that CP contents were gradually decreased in the embryos until the nauplii were hatched. In addition, purified CP was shown to react with specific anti-phosphoserine, anti-phosphothreonine, and anti-phosphotyrosine antibodies suggesting that CP is a phosphoprotein with all types of phosphorylations. Taken together the results suggest that expression of CP in shrimp ovaries is coupled to ovarian development and CP possibly supply nutrition for shrimp embryo.


Assuntos
Proteínas do Ovo/biossíntese , Ovário/metabolismo , Penaeidae/embriologia , Penaeidae/metabolismo , Testículo/metabolismo , Sequência de Aminoácidos , Fenômenos Fisiológicos da Nutrição Animal , Animais , Proteínas do Ovo/genética , Proteínas do Ovo/fisiologia , Feminino , Masculino , Dados de Sequência Molecular , Ovário/fisiologia , Óvulo/metabolismo , Penaeidae/genética , Fosforilação , Coelhos , Testículo/fisiologia
13.
Carbohydr Polym ; 155: 466-474, 2017 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-27702536

RESUMO

This study investigated the effects of a type II arabinogalactan from Anoectochilus formosanus (AGAF) on natural killer (NK) cell-mediated cytotoxicity and the possible underlying mechanisms. This study reported that sustained exposure to AGAF increased NK-92MI cell-mediated cytotoxicity in a time- and concentration-dependent manner, as characterized according to the cellular lactic dehydrogenase leakage from K562 leukemia cells. Additionally, antibody neutralization studies have reported that interferon (IFN)-γ, but not perforin or tumor necrosis factor-α, released by NK-92MI NK cells is crucial in enhancing cytotoxicity through an autocrine loop. In this study, AGAF was further demonstrated to induce IFN-γ expression, increasing the susceptibility to NK-92MI cell-mediated cytotoxicity through the toll-like receptor (TLR)-2, TLR4, extracellular signal-regulated kinase, p38 mitogen-activated protein kinase, and nuclear factor-κB pathways. A pharmacological study revealed that Janus kinase 2/signal transducers and activators of the signal transducers and of transcription 3 signaling are involved in IFN-γ-induced NK cell-mediated cytotoxicity.


Assuntos
Citotoxicidade Imunológica , Galactanos/farmacologia , Interferon gama/imunologia , Células Matadoras Naturais/imunologia , Orchidaceae/química , Humanos , Células K562 , Células Matadoras Naturais/efeitos dos fármacos , Transdução de Sinais
14.
Phytomedicine ; 22(14): 1207-14, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26655402

RESUMO

BACKGROUND: Polysaccharides, considered as immunomodulators with the capacity to activate immunity against microbial pathogens and tumors, have been employed for their dietary and medical benefits. PURPOSE: This study investigated the immunomodulatory effect of polysaccharide such as type II arabinogalactan from Anoectochilus formosanus (AGAF) on dendritic cell (DC) maturation and the underlying molecular mechanisms. METHODS AND RESULTS: Exposing DCs to AGAF induces cell maturation, which is characterized by the upregulation of CD86, CD83, CD80, CD40, and MHC class I and class II expression through flow cytometry analysis and morphological change without cytotoxicity. In addition, AGAF-triggered DC2.4 cells were involved in priming T-cell activation in vitro and in vivo. Transfection of toll-like receptor (TLR) 2 proteins and TLR4 siRNA suppressed DC maturation, suggesting that AGAF induced DC maturation through TLR2 and TLR4. CONCLUSION: These findings indicate that AGAF may be a potentially effective immunomodulator in stimulating DC maturation.


Assuntos
Células Dendríticas/efeitos dos fármacos , Galactanos/farmacologia , Ativação Linfocitária , Orchidaceae/química , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Células Dendríticas/citologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Interferência de RNA , Linfócitos T/citologia , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética
15.
Health Educ Behav ; 42(3): 352-60, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25512072

RESUMO

BACKGROUND: Lack of education is a known barrier to vaccination, but data on the design and effectiveness of interventions remain limited. OBJECTIVE: This study aims to identify the effectiveness of a Facebook-assisted teaching method on female adolescents' knowledge and attitudes about cervical cancer prevention and on their human papillomavirus vaccination intention. METHOD: A quasi-experimental time series research design was used. Two hundred female adolescents at a senior high school in Taipei were recruited into two groups. Following a classroom lecture, one group was provided a Facebook-assisted online discussion, and the other group was provided an in-person discussion forum. A demographic questionnaire and cervical cancer prevention questionnaire were distributed. Data were analyzed for descriptive statistics and generalized estimation equations. RESULTS: Improvement from T0 to T2 in knowledge and attitude scores was 4.204 and 4.496 points, respectively. The Facebook group's improvement in vaccination intention from T0 to T2 was 2.310 times greater than the control group's improvement under conditions of out-of-pocket expenses and 2.368 times greater under conditions of free vaccination. CONCLUSIONS: School-based cervical cancer prevention education can be effective. The Facebook-assisted discussion method was more effective than the in-person discussion. Providing the human papillomavirus vaccine free of charge would increase female adolescents' intention to be vaccinated.


Assuntos
Educação em Saúde/métodos , Conhecimentos, Atitudes e Prática em Saúde , Vacinas contra Papillomavirus/administração & dosagem , Rede Social , Neoplasias do Colo do Útero/prevenção & controle , Adolescente , Feminino , Humanos , Intenção , Aceitação pelo Paciente de Cuidados de Saúde , Fatores Socioeconômicos , Taiwan
16.
Mol Nutr Food Res ; 57(12): 2264-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23901023

RESUMO

The receptor for advanced glycation of end products (RAGE) plays a critical role in the progression of type 2 diabetes (T2D). Soluble RAGE (sRAGE) is one of the RAGE variants, which acts as a decoy domain receptor and competes with RAGE, thus contributing to prevention of T2D. In this study, we conducted clinical trials of (-)-epigallocatechin-3-gallate (EGCG) rich green tea extract (300-900 mg/day) to investigate the effect of EGCG on relationship between S100A12 RAGE ligand and diverse sRAGE in T2D. Moreover, mechanism of sRAGE production also confirmed in vitro. Our data indicated that EGCG could stimulate sRAGE circulation but inhibited RAGE ligand in T2D, and ADAM10-mediated ectodomain shedding of extracellular RAGE was mainly involved in EGCG-stimulated sRAGE circulation. The present evidence indicates that EGCG has a potential to block S100A12-RAGE axis by stimulating sRAGE production through ADAM10-mediated ectodomain shedding of extracellular RAGE. Therefore, EGCG contributes to nutritional strategies for diabetes, not only because of its efficient antioxidant activity to scavenge free radicals, but also because of its ability stimulating sRAGE release in the circulation. Additionally, ADAM10-induced ectodomain shedding of extracellular RAGE leading to sRAGE circulation should be a potential of passive mechanism of sRAGE production to block S100A12-RAGE axis-related pathogenesis of proinflammation and diabetes.


Assuntos
Proteínas ADAM/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Catequina/análogos & derivados , Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/metabolismo , Proteínas de Membrana/metabolismo , Extratos Vegetais/uso terapêutico , Receptores Imunológicos/metabolismo , Proteínas S100/metabolismo , Proteína ADAM10 , Camellia sinensis/química , Catequina/farmacologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Estrutura Terciária de Proteína , Receptor para Produtos Finais de Glicação Avançada , Receptores Imunológicos/sangue , Proteínas S100/sangue , Proteína S100A12
17.
Ann N Y Acad Sci ; 1215: 40-7, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21261640

RESUMO

Higher levels of body fat are associated with increased risk for development of numerous adverse health conditions. Phytochemicals are potential agents to inhibit differentiation of preadipocytes, stimulate lipolysis, and induce apoptosis of existing adipocytes, thereby reducing adipose tissue mass. Resveratrol decreased adipogenesis and viability in maturing preadipocytes; these effects were mediated not only through down-regulating adipocyte specific transcription factors and enzymes but also by genes that modulate mitochondrial function. Additionally, resveratrol increased lipolysis and reduced lipogenesis in mature adipocytes. In addition, combining resveratrol with other natural products produced synergistic activities from actions on multiple molecular targets in the adipocyte life cycle. Treatment of mice with resveratrol alone was shown to improve resistance to weight gain caused by a high-fat diet. Moreover, dietary supplementation of aged ovariectomized rats with a combination of resveratrol and vitamin D, quercetin, and genistein not only decreased weight gain but also inhibited bone loss. Combining several phytochemicals, including resveratrol, or using them as templates for synthesizing new drugs, provides a large potential for using phytochemicals to target adipocyte adipogenesis, apoptosis, and lipolysis.


Assuntos
Adipogenia/efeitos dos fármacos , Tecido Adiposo/efeitos dos fármacos , Estilbenos/farmacologia , Adipogenia/fisiologia , Tecido Adiposo/metabolismo , Animais , Humanos , Lipólise/efeitos dos fármacos , Lipólise/fisiologia , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Resveratrol , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Estilbenos/uso terapêutico
18.
J Med Food ; 14(11): 1352-62, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21663481

RESUMO

Vitamin D and certain natural compounds have been shown to regulate both lipid metabolism and bone formation. Treatments that prevent or reverse age-related increase in bone marrow adiposity could both increase new bone formation and inhibit bone destruction. We tested the hypothesis that dietary supplementation with combinations of vitamin D and phytochemicals inhibits bone loss and decreases adiposity to a greater extent than control or vitamin D-alone diets. Aged ovariectomized female rats (12 months old, n=50, initial body weight=240 g) were given control (AIN-93M diet), vitamin D (2,400 IU/kg), or vitamin D plus resveratrol (16, 80, or 400 mg/kg of diet [low, medium, and high dose, respectively]), quercetin (80, 400, or 2,000 mg/kg of diet), and genistein (64, 256, or 1,040 mg/kg of diet) for 8 weeks. The high-dose treatment (vitamin D+400 mg/kg resveratrol+2,000 mg/kg quercetin+1,040 mg/kg genistein) reduced body weight gain (P<.05) and the fat pad weights (P<.05). This treatment also increased the serum concentration of insulin-like growth factor-1 (P<.05) and the bone mineral content of the femur. Micro-computed tomography and histomorphometric analyses indicated that the high-dose treatment prevented loss of trabecular bone (P<.05) and reduced marrow adipocytes (P<.001) and osteoclasts (P<.05) compared with the control and vitamin D alone (P<.05). We conclude that aged ovariectomized female rats supplemented with vitamin D combined with genistein, quercetin, and resveratrol had improved bone mineral density and reduced body weight gain and a significant decrease in bone marrow adipocytes. The synergistic effects of a combination of phytochemicals with vitamin D may be effective in reducing bone loss and weight gain after menopause.


Assuntos
Doenças Ósseas Metabólicas/prevenção & controle , Suplementos Nutricionais , Combinação de Medicamentos , Fitoterapia/métodos , Vitamina D/administração & dosagem , Aumento de Peso/efeitos dos fármacos , Tecido Adiposo/efeitos dos fármacos , Adiposidade/efeitos dos fármacos , Animais , Densidade Óssea/efeitos dos fármacos , Dieta , Feminino , Fêmur/efeitos dos fármacos , Genisteína/administração & dosagem , Ovariectomia , Quercetina/administração & dosagem , Ratos , Ratos Endogâmicos F344 , Resveratrol , Estilbenos/administração & dosagem
19.
Toxicol Lett ; 204(2-3): 108-17, 2011 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-21575692

RESUMO

Zinc overload is known to cause the death of neural cells. Although the activation of extracellular signal-regulated kinase (ERK) and cytosolic phospholipase A(2) (cPLA(2)) have been implicated in zinc-induced astrocyte death, the detailed mechanisms of their activation and upstream regulatory cascades are incompletely understood. Here, we report that protein kinase C (PKC)- and Src-related Ras/Raf/ERK cascades and ERK-associated cPLA(2) participate in astrocyte death caused by ZnCl(2). Sustained exposure to ZnCl(2) caused damage to astrocytes in a time- and concentration-dependent manner. The cell death caused by ZnCl(2) was accompanied by increased reactive oxygen species (ROS) generation, PKC-α membrane association, Src phosphorylation, Ras membrane association, Raf phosphorylation, ERK phosphorylation, and cPLA(2) activation, and decreased protein phosphatase activity. Pharmacological studies revealed that these activations/inactivations all contributed to ZnCl(2)-induced astrocyte death. ROS, such as superoxide, appear to be a key trigger in response to ZnCl(2) treatment in astrocytes because of the attenuations in protein phosphatase inhibition, signaling activation, and cell death by antioxidant treatments. Mechanistic studies had suggested that ROS/PKC-α/Ras/Raf/ERK and ROS/Src/Ras/Raf/ERK were potential signals linking zinc and cPLA(2). These observations indicated that ROS/PKC-α/Ras/Raf/ERK and ROS/Src/Ras/Raf/ERK signaling and cPLA(2) were actively involved in zinc-induced astrocyte damage.


Assuntos
Astrócitos/efeitos dos fármacos , Cloretos/toxicidade , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Transdução de Sinais/fisiologia , Compostos de Zinco/toxicidade , Animais , Astrócitos/citologia , Morte Celular , Células Cultivadas , Proteína Quinase C/fisiologia , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Quinases raf/fisiologia , Proteínas ras/fisiologia , Quinases da Família src/fisiologia
20.
J Nutr Biochem ; 22(7): 612-24, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21036586

RESUMO

Microglial activation plays a pivotal role in the pathogenesis of neurodegenerative disease by producing excessive proinflammatory cytokines and nitric oxide (NO). Luteolin, a naturally occurring polyphenolic flavonoid antioxidant, has potent anti-inflammatory and neuroprotective properties both in vitro and in vivo. However, the molecular mechanism of luteolin-mediated immune modulation in microglia is not fully understood. In the present study, we report the inhibitory effect of luteolin on lipopolysaccharide (LPS)/interferon γ (IFN-γ)-induced NO and proinflammatory cytokine production in rat primary microglia and BV-2 microglial cells. Luteolin concentration-dependently abolished LPS/IFN-γ-induced NO, tumor necrosis factor α (TNF-α) and interleukin 1ß (IL-1ß) production as well as inducible nitric oxide synthase (iNOS) protein and mRNA expression. Luteolin exerted an inhibitory effect on transcription factor activity including nuclear factor κB (NF-κB), signal transducer and activator of transcription 1 (STAT1) and interferon regulatory factor 1 (IRF-1) in LPS/IFN-γ-activated BV-2 microglial cells. Biochemical and pharmacological studies revealed that the anti-inflammatory effect of luteolin was accompanied by down-regulation of extracellular signal-regulated kinase (ERK), p38, c-Jun N-terminal kinase (JNK), Akt and Src. Further studies have demonstrated that the inhibitory effect of luteolin on intracellular signaling execution and proinflammatory cytokine expression is associated with resolution of oxidative stress and promotion of protein phosphatase activity. Together, these results suggest that luteolin suppresses NF-κB, STAT1 and IRF-1 signaling, thus attenuating inflammatory response of brain microglial cells.


Assuntos
Luteolina/farmacologia , Microglia/efeitos dos fármacos , NF-kappa B/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Regulação para Baixo , Fator Regulador 1 de Interferon , Interleucina-1beta/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Camundongos , Óxido Nítrico/fisiologia , Fosfoproteínas Fosfatases/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição STAT1/efeitos dos fármacos , Fator de Transcrição STAT1/fisiologia , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo
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