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1.
Viruses ; 16(3)2024 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-38543718

RESUMO

Enterovirus A71 (EV-A71) infection typically causes mild illnesses, such as hand-foot-and-mouth disease (HFMD), but occasionally leads to severe or fatal neurological complications in infants and young children. Currently, there is no specific antiviral treatment available for EV-A71 infection. Thus, the development of an effective anti-EV-A71 drug is required urgently. Cordycepin, a major bioactive compound found in Cordyceps fungus, has been reported to possess antiviral activity. However, its specific activity against EV-A71 is unknown. In this study, the potency and role of cordycepin treatment on EV-A71 infection were investigated. Results demonstrated that cordycepin treatment significantly reduced the viral load and viral ribonucleic acid (RNA) level in EV-A71-infected Vero cells. In addition, EV-A71-mediated cytotoxicity was significantly inhibited in the presence of cordycepin in a dose-dependent manner. The protective effect can also be extended to Caco-2 intestinal cells, as evidenced by the higher median tissue culture infectious dose (TCID50) values in the cordycepin-treated groups. Furthermore, cordycepin inhibited EV-A71 replication by acting on the adenosine pathway at the post-infection stage. Taken together, our findings reveal that cordycepin could be a potential antiviral candidate for the treatment of EV-A71 infection.


Assuntos
Desoxiadenosinas , Enterovirus Humano A , Infecções por Enterovirus , Enterovirus , Doença de Mão, Pé e Boca , Animais , Chlorocebus aethiops , Lactente , Criança , Humanos , Pré-Escolar , Enterovirus Humano A/genética , Células Vero , Adenosina/farmacologia , Células CACO-2 , Replicação Viral , Infecções por Enterovirus/tratamento farmacológico , Antígenos Virais , Antivirais/farmacologia
2.
J Cardiothorac Surg ; 18(1): 329, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37964318

RESUMO

BACKGROUND: Aortoesophageal fistula (AEF) is a rare but typically life-threatening condition. Although several treatment strategies exist, including conservative treatment with intraluminal stent graft and open thoracic aortic replacement, the overall outcome remains poor, ranging from 16 to 39%. Furthermore, esophageal reconstruction methods vary between hospitals. Herein, we report a case of aortoesophageal fistula treated using one-stage total reconstruction. CASE PRESENTATION: This case involved a 58-year-old woman who developed acute type A aortic dissection and underwent successful total arch replacement at the other hospital. However, she developed AEF 1 year later and underwent urgent thoracic endovascular aortic repair, which eventually failed. We performed thoracic aortic replacement, total esophagectomy, gastric tube reconstruction, and omental flap in a one-stage operation. The patient was extubated the next day and transferred to the general ward on postoperative day 3. Computed tomography revealed favorable results. CONCLUSIONS: For postoperative AEF, dedicated debridement with reconstruction is more effective than conservative treatment. In an experienced center, post-procedure-related AEF can be easily treated using one-stage reconstruction.


Assuntos
Doenças da Aorta , Implante de Prótese Vascular , Fístula Esofágica , Fístula Vascular , Feminino , Humanos , Pessoa de Meia-Idade , Implante de Prótese Vascular/efeitos adversos , Fístula Vascular/diagnóstico por imagem , Fístula Vascular/etiologia , Fístula Vascular/cirurgia , Doenças da Aorta/complicações , Fístula Esofágica/cirurgia , Fístula Esofágica/complicações , Esofagectomia/métodos
3.
Am J Cancer Res ; 13(4): 1329-1346, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37168338

RESUMO

Leydig cell tumor is the most frequent non-germ cell tumors of testis. The biggest challenge of using radiotherapy to treat testicular cancer is in effectively killing cancer cells and maintaining reproductive function after treatment. Our recently published article showed that cordycepin could enhance radiosensitivity to induce mouse Leydig tumor cell apoptosis by inducing cell cycle arrest, caspase pathway and endoplasmic reticulum (ER) stress. In the present study, the potency and mechanism of a previous combination treatment protocol on reactive oxygen species (ROS) induction and DNA damage were further investigated. Our results reveal that 25 µM cordycepin plus 4 Gy radiation leads to ROS accumulation accompanied by a decrease in heme oxygenase (HO)-1 protein expression in MA-10 mouse Leydig tumor cells. Subsequently, pronounced DNA damage with phosphorylated H2A histone family member X (γ-H2AX) increase and activation of DNA damage-related signaling pathways including double and single stranded break-induced ataxia telangiectasia mutated (ATM)/checkpoint kinase (Chk)2 and ataxia telangiectasia mutated and Rad3 related (ATR)/Chk1 signaling axes were identified. p53-dependent pathway was then initiated ultimately leading to cell death. Preincubated with free radical scavenger, N-acetylcysteine (NAC), down-regulated γ-H2AX expression in treated cells and partially reduced cell death, indicating that ROS overproduction is involved in combination treatment-induced DNA damage. Furthermore, the combination treatment effectively inhibited tumor growth as reflected in the reduction of tumor volume, size and weight, and high expression level of γ-H2AX in tumor tissue in vivo, suggesting that the combination treatment inhibited tumor growth via causing DNA damage in MA-10 cells. In summary, these results expound that the combination treatment of cordycepin and radiation induces MA-10 mouse Leydig tumor cell death through ROS accumulation and DNA damage. This finding can serve as a reference guideline for future clinical therapy of testicular cancer and provide potential targets for anti-cancer drug design.

4.
Mol Med Rep ; 27(2)2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36524366

RESUMO

Although arsenic is an environmental toxicant, arsenic trioxide (ATO) is used to treat acute promyelocytic leukemia (APL) with anticancer effects. Studies have demonstrated oral cancer is in the top 10 cancers in Taiwan. High rate of oral cancers is linked to various behaviors, such as excessive alcohol consumption and tobacco use. Similarly, betel chewing is a strong risk factor in oral cancer. In the present study, oral squamous carcinoma OC3 cells were investigated with the treatments of sodium arsenite (NaAsO2) and dimethylarsenic acid (DMA), respectively, to examine if arsenic compounds have anti­cancer efforts. It was found that 1 µM NaAsO2 and 1 mM DMA for 24 h induced rounded contours with membrane blebbing phenomena in OC3 cells, revealing cell apoptotic characteristics. In addition, NaAsO2 (10­100 µM) and DMA (1­100 mM) significantly decreased OC3 cell survival. In cell cycle regulation detected by flow cytometry, NaAsO2 and DMA significantly augmented percentage of subG1 and G2/M phases in OC3 cells, respectively. Annexin V/PI double staining assay was further used to confirm NaAsO2 and DMA did induce OC3 cell apoptosis. In mechanism investigation, western blotting assay was applied and the results showed that NaAsO2 and DMA significantly induced phosphorylation of JNK, ERK1/2 and p38 and then the cleavages of caspase­8, ­9, ­3 and poly ADP­ribose polymerase (PARP) in OC3 cells, dynamically. In conclusion, NaAsO2 and DMA activated MAPK pathways and then apoptotic pathways to induce OC3 oral cancer cell apoptosis.


Assuntos
Arsenicais , Neoplasias Bucais , Humanos , Ácido Cacodílico/farmacologia , Linhagem Celular Tumoral , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/patologia , Apoptose , Arsenicais/farmacologia
5.
Cancer Med ; 12(3): 3260-3275, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36000705

RESUMO

Arsenic compounds have been applied treating acute promyelocytic 1eukemia and solid tumors with brief mechanism investigations. In fact, we have demonstrated that sodium arsenite plus dimethylarsenic acid could activate apoptosis in MA-10 mouse Leydig tumor cells by inducing caspase pathways. However, detail underlying mechanisms how caspase cascade is regulated remains elusive. Therefore, the apoptotic mechanism of sodium arsenite plus dimethylarsenic acid were examined in MA-10 cells in this study. Our results reveal that Fas/FasL protein expressions were stimulated by sodium arsenite plus dimethylarsenic acid in MA-10 cells. In addition, reactive oxygen species (ROS) generation, cytochrome C release, Bid truncation, and Bax translocation were induced in MA-10 cells by arsenic compounds. Moreover, activation of p38, JNK and ERK1/2, MAPK pathways was stimulated while Akt phosphorylated levels and Akt expression were decreased by sodium arsenite plus dimethylarsenic in MA-10 cells. In conclusion, sodium arsenite and dimethylarsenic acid did activate MAPK pathway plus ROS generation, but suppress Akt pathway, to modulate caspase pathway and then induce MA-10 cell apoptosis.


Assuntos
Arsenitos , Neoplasias , Animais , Camundongos , Proteínas Proto-Oncogênicas c-akt , Espécies Reativas de Oxigênio/metabolismo , Apoptose , Arsenitos/farmacologia , Caspases
6.
7.
Am J Cancer Res ; 12(8): 3601-3624, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36119830

RESUMO

Radiotherapy is a localized treatment commonly used in various types of cancer. However, major limitation of radiotherapy is the development of resistance of tumor cells to radiosensitivity. Cordycepin, a predominant functional component of the Cordyceps sinensis, is considered to use in treating tumor cells. In the present study, we investigated the anticancer effect of the combination of radiation and cordycepin in the treatment of Leydig tumor cells. Results showed that the combination treatment has a synergistic effect significantly suppress cell viability and enhance the radiosensitivity in MA-10 mouse Leydig tumor cells. The combination treatment induced MA-10 cell apoptosis through increasing levels of cleaved caspase-3/-8/-9, poly ADP-ribose polymerase (PARP), and cytochrome c and decreasing levels of B-cell lymphoma 2 (Bcl-2). In addition, prolonged sub-G1 and G2/M arrest accompany with cell cycle-related protein regulation was observed in cells that received the combination treatment. The endoplasmic reticulum (ER) stress-related protein expressions were regulated after MA-10 cells treating with a combination of 100 µM cordycepin and 4 Gy radiation. Furthermore, the combination treatment also decreased the Leydig tumor mass by increasing cell apoptosis in tumor-bearing mice. In conclusion, cordycepin enhances radiosensitivity to induce mouse Leydig tumor cells toward apoptosis in vitro and in vivo. This study will provide a scientific basis for the development of therapeutic regimen of testicular cancer.

8.
Int J Oncol ; 60(2)2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35029282

RESUMO

For a number of years, oral cancer has remained in the top ten most common types of cancer, with an incidence rate that is steadily increasing. In total, ~75% oral cancer cases are associated with lifestyle factors, including uncontrolled alcohol consumption, betel and tobacco chewing, and the excessive use of tobacco. Notably, betel chewing is highly associated with oral cancer in Southeast Asia. Arsenic is a key environmental toxicant; however, arsenic trioxide has been used as a medicine for the treatment of acute promyelocytic leukemia, highlighting its anticancer properties. The present study aimed to investigate the role of arsenic compounds in the treatment of cancer, using FaDu oral squamous carcinoma cells treated with sodium arsenite (NaAsO2) and dimethyl arsenic acid (DMA). The results demonstrated that FaDu cells exhibited membrane blebbing phenomena and high levels of apoptosis following treatment with 10 µM NaAsO2 and 1 mM DMA for 24 h. The results of cell viability assay demonstrated that the rate of FaDu cell survival was markedly reduced as the concentration of arsenic compounds increased from 10 to 100 µM NaAsO2, and 1 to 100 mM DMA. Moreover, flow cytometry was carried out to further examine the effects of arsenic compounds on FaDu cell cycle regulation; the results revealed that treatment with NaAsO2 and DMA led to a significant increase in the percentage of FaDu cells in the sub­G1 and G2/M phases of the cell cycle. An Annexin V/PI double staining assay was subsequently performed to verify the levels of FaDu cell apoptosis following treatment with arsenic compounds. Furthermore, the results of the western blot analyses revealed that the expression levels of caspase­8, ­9 and ­3, and poly ADP­ribose polymerase, as well the levels of phosphorylated JNK and ERK1/2 were increased following treatment with NaAsO2 and DMA in the FaDu cells. On the whole, the results of the present study revealed that treatment with NaAsO2 and DMA promoted the apoptosis of FaDu oral cancer cells, by activating MAPK pathways, as well as the extrinsic and intrinsic apoptotic pathways.


Assuntos
Apoptose/efeitos dos fármacos , Arsênio/farmacologia , Transdução de Sinais/efeitos dos fármacos , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Arsênio/metabolismo , Caspases/metabolismo , Caspases/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Humanos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/farmacologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/fisiopatologia
10.
J Clin Med ; 8(7)2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31336927

RESUMO

Human cardiac progenitor cells isolated from the same host may have advantages over other sources of stem cells. The aim of this study is to establish a new source of human progenitor cells collected from a waste product, pericardiac effusion fluid, after open-heart surgery in children with congenital heart diseases. The fluid was collected every 24 h for 2 days after surgery in 37 children. Mononuclear cells were isolated and expanded in vitro. These pericardial effusion-derived progenitor cells (PEPCs) exhibiting cardiogenic lineage markers, were highly proliferative and enhanced angiogenesis in vitro. Three weeks after stem cell transplantation into the ischemic heart in mice, cardiac ejection fraction was improved significantly without detectable progenitor cells. Gene expression profiles of the repaired hearts revealed activation of several known repair mechanisms including paracrine effects, cell migration, and angiogenesis. These progenitor cells may have the potential for heart regeneration.

11.
Front Psychiatry ; 10: 422, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31281269

RESUMO

Young people experience high rates of mental health issues. However, many do not seek professional help. In order to encourage help-seeking behavior among young people, it is important to ensure that services are youth-friendly. This study aims to evaluate the Community Health Assessment Team (CHAT)'s mental health assessment service model using the World Health Organization (WHO) youth-friendly health service framework of accessibility, acceptability, and appropriateness (AAA), and to ascertain the extent to which the CHAT service model is youth-friendly. Three hundred young people aged 16-30 years, who had gone through CHAT mental health assessments, completed a 27-item questionnaire. Majority rated the items in the questionnaire favorably. Our results suggest that majority of the young people who accessed CHAT mental health assessment service found it to be youth-friendly.

12.
Viruses ; 10(12)2018 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-30563052

RESUMO

Enterovirus A71 (EV-A71) has emerged as a major pathogen causing hand, foot, and mouth disease, as well as neurological disorders. The host immune response affects the outcomes of EV-A71 infection, leading to either resolution or disease progression. However, the mechanisms of how the mammalian innate immune system detects EV-A71 infection to elicit antiviral immunity remain elusive. Here, we report that the Toll-like receptor 3 (TLR3) is a key viral RNA sensor for sensing EV-A71 infection to trigger antiviral immunity. Expression of TLR3 in HEK293 cells enabled the cells to sense EV-A71 infection, leading to type I, IFN-mediated antiviral immunity. Viral double-stranded RNA derived from EV-A71 infection was a key ligand for TLR3 detection. Silencing of TLR3 in mouse and human primary immune cells impaired the activation of IFN-ß upon EV-A71 infection, thus reinforcing the importance of the TLR3 pathway in defending against EV-A71 infection. Our results further demonstrated that TLR3 was a target of EV-A71 infection. EV-A71 protease 2A was implicated in the downregulation of TLR3. Together, our results not only demonstrate the importance of the TLR3 pathway in response to EV-A71 infection, but also reveal the involvement of EV-A71 protease 2A in subverting TLR3-mediated antiviral defenses.


Assuntos
Cisteína Endopeptidases/imunologia , Enterovirus Humano A/imunologia , RNA Viral/imunologia , Receptor 3 Toll-Like/imunologia , Animais , Células Cultivadas , Regulação para Baixo , Enterovirus Humano A/enzimologia , Inativação Gênica , Células HEK293 , Humanos , Imunidade Inata , Interferon beta/imunologia , Camundongos , Camundongos Endogâmicos C57BL , RNA de Cadeia Dupla/imunologia , Receptor 3 Toll-Like/genética
13.
Emerg Infect Dis ; 24(9): 1709-1712, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30124404

RESUMO

We compared 2 tick-borne encephalitis virus strains isolated from 2 different foci that cause different symptoms in tick-borne encephalitis patients, from neurologic to mild gastrointestinal symptoms. We compared neuroinvasiveness, neurovirulence, and proinflammatory cytokine response in mice and found unique differences that contribute to our understanding of pathogenesis.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos/patogenicidade , Encefalite Transmitida por Carrapatos/virologia , Animais , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Índice de Gravidade de Doença , Especificidade da Espécie , Virulência
14.
Sci Rep ; 6: 39265, 2016 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-27982069

RESUMO

The tick-borne encephalitis virus (TBEV) is a flavivirus transmitted to humans, usually via tick bites. The virus causes tick-borne encephalitis (TBE) in humans, and symptoms range from mild flu-like symptoms to severe and long-lasting sequelae, including permanent brain damage. It has been suggested that within the population of viruses transmitted to the mammalian host, quasispecies with neurotropic properties might become dominant in the host resulting in neurological symptoms. We previously demonstrated the existence of TBEV variants with variable poly(A) tracts within a single blood-fed tick. To characterize the role of the poly(A) tract in TBEV replication and virulence, we generated infectious clones of Torö-2003 with the wild-type (A)3C(A)6 sequence (Torö-6A) or with a modified (A)3C(A)38 sequence (Torö-38A). Torö-38A replicated poorly compared to Torö-6A in cell culture, but Torö-38A was more virulent than Torö-6A in a mouse model of TBE. Next-generation sequencing of TBEV genomes after passaging in cell culture and/or mouse brain revealed mutations in specific genomic regions and the presence of quasispecies that might contribute to the observed differences in virulence. These data suggest a role for quasispecies development within the poly(A) tract as a virulence determinant for TBEV in mice.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos/genética , Poli A/genética , Regiões 3' não Traduzidas/genética , Células A549 , Animais , Sequência de Bases , Chlorocebus aethiops , Vírus da Encefalite Transmitidos por Carrapatos/patogenicidade , Vírus da Encefalite Transmitidos por Carrapatos/fisiologia , Encefalite Transmitida por Carrapatos/patologia , Encefalite Transmitida por Carrapatos/veterinária , Encefalite Transmitida por Carrapatos/virologia , Genoma Viral , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Plasmídeos/genética , Plasmídeos/metabolismo , RNA Viral/química , RNA Viral/isolamento & purificação , RNA Viral/metabolismo , Alinhamento de Sequência , Carrapatos/virologia , Células Vero , Virulência , Replicação Viral
15.
World J Gastroenterol ; 22(22): 5183-92, 2016 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-27298561

RESUMO

AIM: To investigate the effect of miR-106b on tumor progression in hepatitis B virus (HBV)-associated hepatocellular carcinoma (HCC). METHODS: A total of 120 patients who underwent liver resection for HCC at National Cheng Kung University Hospital were enrolled in the present study. MicroRNA (miRNA) array was first used to screen the miRNA expression profiles in HCC patients. The clinical records were retrospectively analyzed, and correlations with the miRNA expression profiles were evaluated. The mRNA expression levels of the miR-106b-25 cluster (miR-106b, miR-93 and miR-25), and MCM7 in tumor and non-tumor samples were quantitated using quantitative real-time reverse transcription-polymerase chain reaction (q-RT-PCR) analysis, and correlations in the levels of miR-106b, miR-93 and miR-25 expression were calculated. Kaplan-Meier overall and disease-free survival rates of HBV-associated HCC patients were analyzed using the log-rank test based on miR-106b expression. The comparison of the miR-106b expression levels in patients with different clinical outcomes was analyzed using Mann-Whitney U tests. Furthermore, a hepatitis B virus X protein (HBx) expression plasmid was transfected into Huh7 and Hep 3B cells. The expression levels of the miR-106b-25 cluster and MCM7 in HBx-expressing Huh7 and Hep 3B cells were detected using q-RT-PCR. RESULTS: miRNA array screening showed that miR-106b and its cluster, miR-93 and miR-25 were up-regulated in HCC patients (P < 0.01). The value of miR-106b expression in HBV-associated HCC patients was significantly higher than that in HCV- (P < 0.05) or non-B/non-C- (P < 0.001) associated HCC patients. The expression of the miR-106b-25 cluster was significantly higher in tumor tissue (P < 0.001) and associated with the host gene, MCM7, in clinical specimens from HBV-associated HCC patients. Furthermore, the expression levels of miR-106b, miR-93 and miR-25 were positively correlated in HBV-associated HCC tissues (miR-106 vs miR-93, r = 0.75; miR-93 vs miR-25, r = 0.69; miR-106b vs miR-25, r = 0.33). The overall and disease-free survival curves showed that high-miR-106b expression was correlated with the poor prognosis of HBV-associated HCC. HCC differentiation was significantly correlated with miR-106b expression (P < 0.05). Lower miR-106b expression levels resulted in the well differentiation of HCC. Moreover, the expression of the miR106b-25 cluster and MCM7 was up-regulated in Huh7 and Hep 3B cells after transfection with the HBx expression plasmid. CONCLUSION: The data obtained in the present study suggests that HBx enhances miR-106b transcription to promote tumor progression in HBV-associated HCC.


Assuntos
Carcinoma Hepatocelular/metabolismo , Vírus da Hepatite B/metabolismo , Hepatite B/complicações , Neoplasias Hepáticas/metabolismo , MicroRNAs/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/virologia , Linhagem Celular Tumoral , Intervalo Livre de Doença , Feminino , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Hepatite B/virologia , Vírus da Hepatite B/genética , Vírus da Hepatite B/patogenicidade , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/virologia , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Transdução de Sinais , Fatores de Tempo , Transativadores/genética , Transativadores/metabolismo , Transcrição Gênica , Transfecção , Proteínas Virais Reguladoras e Acessórias
16.
Early Interv Psychiatry ; 10(2): 171-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25277826

RESUMO

AIM: Adolescence and early adulthood is marked by physical, emotional and psychological changes, and is the peak onset of mental disorders. Internationally, one-fifth of children and adolescents have serious mental health problems, yet services catering to them are scarce. Locally, traditional mental health services are associated with much stigma. In 2009, the Community Health Assessment Team (CHAT), a youth-focused outreach and assessment service, was set up to address service gaps and care barriers. METHODS: CHAT's key offering is a free and confidential mental health assessment service to facilitate help-seeking individuals between the ages of 16 and 30 gain access to early treatment. Young persons' profile and assessment outcomes were collected and entered into a database. RESULTS: Between May 2009 and March 2013, CHAT received 601 referrals: 40.1% (241/601) from young persons themselves and 40.9% (246/601) from school or community counsellors. 79.2% (313/395) of those assessed had mental health issues. 61.5% (243/395) were referred to specialist clinics and 28.6% (113/395) to school or community counsellors. CONCLUSION: There is a steady increase in our referrals; majority are self-referred or referred from school and community counsellors. This attests to the success of our general outreach and targeted capacity-building efforts. Cognizant of young persons' distress, CHAT continues to work with downstream services for continuity of care, which also presents opportunities to consolidate and expand our network of specialist and community partners. Future directions seek to address current challenges: having a mobile platform to complement our face-to-face assessments, and building collaborations to provide holistic services for young persons.


Assuntos
Intervenção Médica Precoce/organização & administração , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Serviços de Saúde Mental/organização & administração , Equipe de Assistência ao Paciente/organização & administração , Encaminhamento e Consulta/estatística & dados numéricos , Adolescente , Adulto , Relações Comunidade-Instituição , Feminino , Humanos , Masculino , Desenvolvimento de Programas , Singapura/epidemiologia , Adulto Jovem
17.
J Virol ; 89(14): 7028-37, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25926657

RESUMO

UNLABELLED: Enterovirus 71 (EV71) infection causes severe mortality involving multiple possible mechanisms, including cytokine storm, brain stem encephalitis, and fulminant pulmonary edema. Gamma interferon (IFN-γ) may confer anti-EV71 activity; however, the claim that disease severity is highly correlated to an increase in IFN-γ is controversial and would indicate an immune escape initiated by EV71. This study, investigating the role of IFN-γ in EV71 infection using a murine model, showed that IFN-γ was elevated. Moreover, IFN-γ receptor-deficient mice showed higher mortality rates and more severe disease progression with slower viral clearance than wild-type mice. In vitro results showed that IFN-γ pretreatment reduced EV71 yield, whereas EV71 infection caused IFN-γ resistance with attenuated IFN-γ signaling in IFN regulatory factor 1 (IRF1) gene transactivation. To study the immunoediting ability of EV71 proteins in IFN-γ signaling, 11 viral proteins were stably expressed in cells without cytotoxicity; however, viral proteins 2A and 3D blocked IFN-γ-induced IRF1 transactivation following a loss of signal transducer and activator of transcription 1 (STAT1) nuclear translocation. Viral 3D attenuated IFN-γ signaling accompanied by a STAT1 decrease without interfering with IFN-γ receptor expression. Restoration of STAT1 or blocking 3D activity was able to rescue IFN-γ signaling. Interestingly, viral 2A attenuated IFN-γ signaling using another mechanism by reducing the serine phosphorylation of STAT1 following the inactivation of extracellular signal-regulated kinase without affecting STAT1 expression. These results demonstrate the anti-EV71 ability of IFN-γ and the immunoediting ability by EV71 2A and 3D, which attenuate IFN-γ signaling through different mechanisms. IMPORTANCE: Immunosurveillance by gamma interferon (IFN-γ) may confer anti-enterovirus 71 (anti-EV71) activity; however, the claim that disease severity is highly correlated to an increase in IFN-γ is controversial and would indicate an immune escape initiated by EV71. IFN-γ receptor-deficient mice showed higher mortality and more severe disease progression, indicating the anti-EV71 property of IFN-γ. However, EV71 infection caused cellular insusceptibility in response to IFN-γ stimulation. We used an in vitro system with viral protein expression to explore the novel IFN-γ inhibitory properties of the EV71 2A and 3D proteins through the different mechanisms. According to this study, targeting either 2A or 3D pharmacologically and/or genetically may sustain a cellular susceptibility in response to IFN-γ, particularly for IFN-γ-mediated anti-EV71 activity.


Assuntos
Enterovirus Humano A/imunologia , Infecções por Enterovirus/imunologia , Interações Hospedeiro-Patógeno , Interferon gama/antagonistas & inibidores , Transdução de Sinais , Proteínas Virais/metabolismo , Animais , Linhagem Celular , Modelos Animais de Doenças , Humanos , Camundongos Endogâmicos C57BL , Camundongos Knockout
18.
Appl Opt ; 51(28): 6870-80, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23033105

RESUMO

The headlamp of the automobile is a very important device for the safety of driving in the dark. Therefore, the distribution of the light designed to provide forward and lateral illumination needs to meet the requirements of various regulations. Traditional measurement of the distribution has been based on a point-by-point approach using a goniophotometer. In this paper, an imaging photometer is developed by combining a regular digital camera and a high dynamic range imaging technique to achieve faster and more complete measurement of the entire distribution. The experimental results indicate that errors of the measurements are within 10% of the true values, which is better than the 20% requirements of the industry.

19.
J Med Virol ; 84(11): 1779-89, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22997081

RESUMO

Type I interferons (IFNs) represent an essential innate defense mechanism for controlling enterovirus 71 (EV 71) infection. Mice inoculated with EV 71 produced a significantly lower amount of type I IFNs than those inoculated with poly (I:C), adenovirus type V, or coxsackievirus B3 (CB3). EV 71 infection, however, mounted a proinflammatory response with a significant increase in the levels of serum and brain interleukin (IL)-6, monocyte chemoattractant protein-1, tumor necrosis factor, and IFN-γ. EV 71 infection abolished both poly (I:C)- and CB3-induced type I IFN production of mice. Such effect was not extended to other enteroviruses including coxsackievirus A24, B2, B3, and echovirus 9, as mice infected with these viruses retained type I IFN responsiveness upon poly (I:C) challenge. In addition, EV 71-infected RAW264.7 cells produced significantly lower amount of type I IFNs than non-infected cells upon poly (I:C) stimulation. The inhibitory effect of EV 71 on type I IFN production was attributed to the viral protein 3C, which was confirmed using over-expression systems in both mice and RAW264.7 cells. The 3C over-expression, however, did not interfere with poly (I:C)-induced proinflammatory cytokine production. These findings indicate that EV 71 can hamper the host innate defense by blocking selectively type I IFN synthesis through the 3C viral protein.


Assuntos
Cisteína Endopeptidases/metabolismo , Enterovirus Humano A/imunologia , Enterovirus Humano A/patogenicidade , Interferon Tipo I/antagonistas & inibidores , Proteínas Virais/metabolismo , Fatores de Virulência/metabolismo , Proteases Virais 3C , Animais , Linhagem Celular , Evasão da Resposta Imune , Tolerância Imunológica , Macrófagos/imunologia , Macrófagos/virologia , Camundongos
20.
Respir Res ; 12: 147, 2011 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-22054060

RESUMO

BACKGROUND: Neonatal mice developed neurological disease and pulmonary dysfunction after an infection with a mouse-adapted human Enterovirus 71 (EV71) strain MP4. However, the hallmark of severe human EV71 infection, pulmonary edema (PE), was not evident. METHODS: To test whether EV71-induced PE required a proinflammatory cytokine response, exogenous pro-inflammatory cytokines were administered to EV71-infected mice during the late stage of infection. RESULTS: After intracranial infection of EV71/MP4, 7-day-old mice developed hind-limb paralysis, pulmonary dysfunction, and emphysema. A transient increase was observed in serum IL-6, IL-10, IL-13, and IFN-γ, but not noradrenaline. At day 3 post infection, treatment with IL-6, IL-13, and IFN-γ provoked mild PE and severe emphysema that were accompanied by pulmonary dysfunction in EV71-infected, but not herpes simplex virus-1 (HSV-1)-infected control mice. Adult mice did not develop PE after an intracerebral microinjection of EV71 into the nucleus tractus solitarii (NTS). While viral antigen accumulated in the ventral medulla and the NTS of intracerebrally injected mice, neuronal loss was observed in the ventral medulla only. CONCLUSIONS: Exogenous IL-6, IL-13, and IFN-γ treatment could induce mild PE and exacerbate pulmonary abnormality of EV71-infected mice. However, other factors such as over-activation of the sympathetic nervous system may also be required for the development of classic PE symptoms.


Assuntos
Enterovirus Humano A , Infecções por Enterovirus/patologia , Interferon gama/toxicidade , Interleucina-13/toxicidade , Interleucina-6/toxicidade , Pulmão/patologia , Edema Pulmonar/patologia , Enfisema Pulmonar/patologia , Animais , Animais Recém-Nascidos , Chlorocebus aethiops , Enterovirus Humano A/imunologia , Enterovirus Humano A/patogenicidade , Infecções por Enterovirus/sangue , Infecções por Enterovirus/imunologia , Humanos , Interferon gama/sangue , Interleucina-13/sangue , Interleucina-6/sangue , Pulmão/imunologia , Pulmão/virologia , Camundongos , Camundongos Endogâmicos ICR , Paralisia/imunologia , Paralisia/patologia , Paralisia/virologia , Edema Pulmonar/sangue , Edema Pulmonar/imunologia , Enfisema Pulmonar/imunologia , Enfisema Pulmonar/virologia , Células Vero
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