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1.
J Virol ; 94(12)2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32269123

RESUMO

Avian influenza viruses occasionally infect and adapt to mammals, including humans. Swine are often described as "mixing vessels," being susceptible to both avian- and human-origin viruses, which allows the emergence of novel reassortants, such as the precursor to the 2009 H1N1 pandemic. ANP32 proteins are host factors that act as influenza virus polymerase cofactors. In this study, we describe how swine ANP32A, uniquely among the mammalian ANP32 proteins tested, supports the activity of avian-origin influenza virus polymerases and avian influenza virus replication. We further show that after the swine-origin influenza virus emerged in humans and caused the 2009 pandemic, it evolved polymerase gene mutations that enabled it to more efficiently use human ANP32 proteins. We map the enhanced proviral activity of swine ANP32A to a pair of amino acids, 106 and 156, in the leucine-rich repeat and central domains and show these mutations enhance binding to influenza virus trimeric polymerase. These findings help elucidate the molecular basis for the mixing vessel trait of swine and further our understanding of the evolution and ecology of viruses in this host.IMPORTANCE Avian influenza viruses can jump from wild birds and poultry into mammalian species such as humans or swine, but they only continue to transmit if they accumulate mammalian adapting mutations. Pigs appear uniquely susceptible to both avian and human strains of influenza and are often described as virus "mixing vessels." In this study, we describe how a host factor responsible for regulating virus replication, ANP32A, is different between swine and humans. Swine ANP32A allows a greater range of influenza viruses, specifically those from birds, to replicate. It does this by binding the virus polymerase more tightly than the human version of the protein. This work helps to explain the unique properties of swine as mixing vessels.


Assuntos
Vírus da Influenza A Subtipo H1N1/genética , Proteínas Nucleares/genética , Infecções por Orthomyxoviridae/genética , Proteínas de Ligação a RNA/genética , RNA Polimerase Dependente de RNA/genética , Proteínas Virais/genética , Animais , Sítios de Ligação , Linhagem Celular , Galinhas , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Regulação da Expressão Gênica , Especificidade de Hospedeiro , Humanos , Vírus da Influenza A Subtipo H1N1/metabolismo , Modelos Moleculares , Mutação , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Infecções por Orthomyxoviridae/metabolismo , Infecções por Orthomyxoviridae/virologia , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , RNA Polimerase Dependente de RNA/química , RNA Polimerase Dependente de RNA/metabolismo , Transdução de Sinais , Suínos , Proteínas Virais/química , Proteínas Virais/metabolismo , Replicação Viral
2.
Hum Reprod ; 34(7): 1291-1301, 2019 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-31188433

RESUMO

STUDY QUESTION: Can of Clinical Genetics, Maastricht University Medical Centre, Maastricht kisspeptin and its analogues regulate the motility of human decidual stromal cells and what intracellular signaling pathways are involved? SUMMARY ANSWER: Kisspeptin analogue-mediated cell motility in human decidual stromal cells via the focal adhesion kinase (FAK)-steroid receptor coactivator (Src) pathway suggesting that kisspeptin may modulate embryo implantation and decidual programming in human pregnancy. WHAT IS KNOWN ALREADY: The extravillous trophoblast invades the maternal decidua during embryo implantation and placentation. The motile behavior and invasive potential of decidual stromal cells regulate embryo implantation and programming of human pregnancy. STUDY DESIGN, SIZE, DURATION: Human decidual stromal cells were isolated from healthy women undergoing elective termination of a normal pregnancy at 6- to 12-week gestation, after informed consent. PARTICIPANTS/MATERIALS, SETTING, METHODS: Kisspeptin analogues were synthetic peptides. Cell motility was estimated by an invasion and migration assay. Immunoblot analysis was performed to investigate the expression of kisspeptin receptor and the effects of kisspeptin analogues on the phosphorylation of FAK and Src. Small interfering RNAs (siRNAs) were used to knock down the expression of kisspeptin receptor, FAK, Src, matrix metallo-proteinases (MMPs) 2 and 9, and extracellular signal-regulated protein kinase (ERK) 1/2. MAIN RESULTS AND THE ROLE OF CHANCE: The kisspeptin receptor was expressed in human decidual stromal cells. Kisspeptin agonist decreased, but antagonist increased, cell motility. Kisspeptin agonist decreased the phosphorylation of FAK and Src tyrosine kinases, whereas antagonist increased it. These effects on phosphorylation were abolished by kisspeptin receptor siRNA. The activation of cell motility by kisspeptin analogues was suppressed by siRNA knockdown of endogenous FAK (decreased 66%), Src (decreased 60%), kisspeptin receptor (decreased 26%), MMP-2 (decreased 36%), MMP-9 (decreased 23%), and ERK 1/2 inhibitor (decreased 27%). LIMITATIONS, REASONS FOR CAUTION: Human decidual stromal cells were obtained from women having terminations after 6-12 weeks of pregnancy and differences in timing could affect their properties. WIDER IMPLICATIONS OF THE FINDINGS: Kisspeptin acting within the endometrium has a potential modulatory role on embryo implantation and decidual programming of human pregnancy. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by grant NSC-104-2314-B-182A-146-MY2 (to H.-M.W.) from the Ministry of Science and Technology, Taiwan, and grants CMRPG3E0401 and CMRPG3E0402 (to H.-M.W.). This work was also supported by grants from the Canadian Institutes of Health Research to P.C.K.L. P.C.K.L. is the recipient of a Child & Family Research Institute Distinguished Investigator Award. The authors have no conflicts of interest to disclose. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Movimento Celular , Decídua/citologia , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Kisspeptinas/fisiologia , Quinases da Família src/metabolismo , Adulto , Feminino , Humanos , Sistema de Sinalização das MAP Quinases , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Cultura Primária de Células , Células Estromais/fisiologia
3.
S Afr J Surg ; 56(2): 59-62, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30010266

RESUMO

BACKGROUND: Despite multiple studies comparing the two methods, the real advantages of laparoscopic appendicectomy (LA) compared to open appendicectomy (OA) are still unclear. Purpose of the current study was to compare the results between the two techniques in a district general hospital. METHODS: The electronic records of all patients who underwent OA or LA in a one year period were reviewed retrospectively. The comparative data points assessed included age, gender, overall complications, length of stay and Clavien-Dindo Classification of Surgical Complications, including the rates of the main types of complications. RESULTS: 300 patients were included in the study. 166 patients underwent OA and 134 patients LA. Postoperative complications were documented in 26 patients (8.7%). LA was employed predominantly in female patients (p = 0.004) and in older patients (p = 0.0015) and was associated with significantly more negative appendicectomies than OA (p = 0.002). No statistically significant difference was noted with regards to the length of hospital stay (p = 0.577), overall postoperative morbidity (p = 0.543) and grading of complications (p = 0.460). Finally, following comparison of the incidence of specific types of complications, only wound infections were significantly different, in favour of LA. CONCLUSION: LA is safe and effective, however, besides the lower incidence of wound sepsis, demonstrates no clear advantage over OA. The selection between OA and LA should thus be tailored to the clinical scenario and the surgeon's preference.


Assuntos
Apendicectomia/métodos , Apendicite/cirurgia , Laparoscopia/métodos , Laparotomia/métodos , Adulto , Idoso , Apendicectomia/efeitos adversos , Apendicite/diagnóstico , Estudos de Coortes , Bases de Dados Factuais , Feminino , Hospitais de Distrito , Hospitais Gerais , Humanos , Laparoscopia/efeitos adversos , Laparotomia/efeitos adversos , Tempo de Internação/estatística & dados numéricos , Londres , Masculino , Pessoa de Meia-Idade , Segurança do Paciente/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/fisiopatologia , Prognóstico , Estudos Retrospectivos , Medição de Risco , Infecção da Ferida Cirúrgica/diagnóstico , Infecção da Ferida Cirúrgica/epidemiologia , Resultado do Tratamento , Reino Unido
4.
Phytomedicine ; 44: 56-64, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29895493

RESUMO

BACKGROUND: Pancreatic cancer, associated with poor prognosis and low survival rate, has been the fourth leading cause of cancer-related death in the US. Although gemcitabine (Gem) is the first-line chemotherapeutic drug in the management of pancreatic cancer, the median survival extension is only 1.5 months, indicating unsatisfactory clinical results. Therefore, exploring agents that can enhance the anti-cancer activity of Gem would be an attractive strategy. PURPOSE: Our previous studies have demonstrated that eriocalyxin b (EriB), an ent­kaurane diterpenoid isolated from Isodon eriocalyx (Dunn.) Hara, possesses anti-pancreatic cancer effects, thus acting as a potential therapeutic agent. In this study, we further investigated whether EriB or the ethanol extract of I. eriocalyx (Isodon) could potentiate the cytotoxic activity of Gem in human pancreatic adenocarcinoma cells. In addition, the mechanism associated with their effects was also studied. METHODS: The anti-proliferation effect was assessed by MTT assay and Ki-67 immunostaining. The combination effect (addition, synergism and antagonism) of various agents was calculated by the Calcusyn software (Biosoft), utilizing the T.C. Chou Method. Apoptosis was detected using Annexin V and PI double staining followed by quantitative flow cytometry. Protein expression regulated by various treatments was analyzed by western blotting. RESULTS: The combination index revealed that Gem and EriB (or Isodon extract) had synergistic anti-proliferative effect. Both cellular apoptotic and anti-proliferative effects of Gem were significantly increased after combination with EriB (or Isodon extract). The underlying mechanisms involved in the combination effects were elucidated, which include: (1) increased activation of the caspase cascade; (2) reduction of PDK1 and AKT phosphorylation; (3) induction of JNK phosphorylation by Isodon and Gem combination. CONCLUSION: Gem and EriB (or Isodon extract) taken together in combination regulated PDK1/AKT1/caspase and JNK signaling and promoted apoptosis synergistically, which may contribute to the much increased anti-proliferative activity compared to either agent alone.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Diterpenos/farmacologia , Isodon/química , Neoplasias Pancreáticas/tratamento farmacológico , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Caspases/metabolismo , Linhagem Celular Tumoral , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Diterpenos/administração & dosagem , Humanos , Sistema de Sinalização das MAP Quinases , Neoplasias Pancreáticas/patologia , Fosforilação/efeitos dos fármacos , Extratos Vegetais/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Piruvato Desidrogenase Quinase de Transferência de Acetil , Gencitabina
5.
J Med Econ ; 20(5): 541-548, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28277030

RESUMO

BACKGROUND: EOX (epirubicin, oxaliplatin, Xeloda; capecitabine) and FOLFOX4 (5-fluorouracil (5-FU), leucovorin, oxaliplatin) are the common chemotherapy regimens used in the treatment of advanced gastric cancer (aGC) in Hong Kong. This study aimed to compare the costs of these therapies for aGC patients from both the healthcare and societal perspectives. It should be noted that, while FOLFOX4 is routinely administered in an outpatient setting in North America and Europe, inpatient setting is adopted in Hong Kong instead, incurring hospitalization cost as a result. METHODS: Fifty-eight patients were identified from the electronic records in two public tertiary hospitals, with 45 and 13 receiving EOX and FOLFOX4 regimens, respectively. Healthcare cost was direct medical costs including drugs, clinic follow-up, hospitalization, diagnostic laboratories, and radiographs. Societal cost refers to indirect costs such as patient time and travel costs. Cost items were further classified as "expected" or "unexpected". All cost data was expressed in US dollars. RESULTS: Patients in the EOX and FOLFOX4 arm received an average of 5.3 and 7.8 cycles of treatment, respectively. The capecitabine-based regimen group had a higher expected medication cost per cycle when compared to the 5-FU-based treatment group (US$290.3 vs US$66.9, p < .001), but lower expected hospitalization costs (US$76.9 vs US$1,269.2, p < .001). The total healthcare cost and total societal cost per patient was reduced by 67.2% (US$5,691.9 vs US$17,357.4, p < .001) and 25.3% (US$3,090.5 vs US$4,135.1, p = .001), respectively, in the capecitabine-based regimen group. Sensitivity analyses based on full cycle regimen costs and net capecitabine or 5-FU/leucovorin costs still showed EOX to be less costly than FOLFOX4. CONCLUSION: The capecitabine-based regimen, EOX, was found to generate significant cost saving from both the healthcare and societal perspectives in regions in which FOLFOX4 is given in an inpatient setting.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/economia , Capecitabina/economia , Fluoruracila/economia , Neoplasias Gástricas/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Capecitabina/uso terapêutico , Efeitos Psicossociais da Doença , Análise Custo-Benefício , Feminino , Fluoruracila/uso terapêutico , Gastos em Saúde/estatística & dados numéricos , Serviços de Saúde/economia , Serviços de Saúde/estatística & dados numéricos , Hong Kong , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Econométricos , Estadiamento de Neoplasias , Estudos Retrospectivos
6.
Curr Mol Med ; 16(8): 747-758, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27658467

RESUMO

OBJECTIVES: The present study was designed to investigate the effects of calcitriol (the active hormonal metabolite of vitamin D) on hepatic metabolic abnormalities in type 2 diabetes. METHODS: Type 2 diabetic db/db mice were used to investigate the effects of calcitriol on hepatic and systemic metabolic disorders. HepG2 cells cultured in insulin-resistant conditions were used to examine the potential mechanisms for calcitriol-induced changes in hepatic lipid and glucose metabolism. RESULTS: 8-week calcitriol treatment ameliorated abnormal hepatic lipid and glucose production in db/db mice. In HepG2 cells under insulin-resistant condition, calcitriol increased cytosolic calcium concentration and induced 5'-AMP-activated protein kinase/acetyl-CoAcarboxylase (AMPK/ACC) phosphorylation via the Ca2+/calmodulin-dependent protein kinase kinase β (CaMKKβ) pathway, contributing to the reductions in hepatic triglyceride accumulation and glucose output. Calcitriol also induced AMPK/ACC phosphorylation in liver of db/db mice. CONCLUSION: Our data indicate that calcitriol, at above-physiological serum concentrations, reduces hepatic triglyceride accumulation and glucose output, at least in part through activation of Ca2+/CaMKKß/AMPK under insulin-resistant condition.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Calcitriol/farmacologia , Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/metabolismo , Cálcio/metabolismo , Glucose/metabolismo , Resistência à Insulina , Fígado/metabolismo , Triglicerídeos/metabolismo , Animais , Biomarcadores , Diabetes Mellitus Tipo 2/metabolismo , Modelos Animais de Doenças , Ativação Enzimática , Células Hep G2 , Humanos , Hiperglicemia/metabolismo , Insulina/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Camundongos , Fosforilação
7.
Curr Mol Med ; 16(3): 299-311, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26917260

RESUMO

Although GHRH and GHRH-R are recognized as key factors in placental development, little is known about the mechanism(s) of the regulation in trophoblastic cells during placental development. The objective of this study is to determine the potential relationship between the expression levels of GHRH-R and the placental and JEG-3 cell function. Furthermore, we aim to investigate the downstream pathways of GHRH/GHRH-R axis in the control of the JEG-3 cell viability and apoptosis. In this study, we detected the expression pattern of GHRH-R in human chorionic villous tissues and JEG-3 cell. Then, we evaluated the effects of GHRH/GHRH-R and the downstream pathways by using GHRH antagonist (JMR-132) on JEG-3 cell. Our present study found the expressions of GHRH-R in placental villous tissues and JEG-3 cell, and the expression levels of GHRH-R was significantly lower in villous tissues of early pregnancy loss when compared to normal controls. JMR-132 inhibited cellular viability and induced apoptosis in JEG-3 cell in a time and dosedependent manners through activation of caspase-3, p38, and p53, as well as inhibition of phosphorylation of Akt. Interestingly, ER stress markers such as GRP78, ubiquitinated proteins and phospho-eIF2α were significantly increased in JEG-3 cell after being treated with JMR-132. Conversely, pretreated with salubrinal (a selective inhibition of protein phosphatase 1-mediated eIF2α dephosphorylation), JEG-3 cells were rescued from JMR-132-mediated cell growth inhibition, and abolished JMR-132-induced cleaved caspase-3, CHOP, phospho-p53, and ubiquitinated proteins accumulation. Knockdown of endogenous GHRH-R significantly abolished the JMR-132-induced cleaved caspase-3 and activation of p38. In conclusion, our results, for the first time, demonstrated the expression levels of GHRH-R were closely related to the placental function. Inhibition of GHRH-R by using GHRH antagonist in JEG-3 cell may reduce cell viability and induce apoptosis through inactivation of Akt and ER stress via phosphorylation of eIF2α. These observations have enriched our understanding on the function of GHRH/GHRH-R axis and the downstream pathways in the control of the placental development. The Most Important Aspect of the Paper: Our present study for the first time provided evidences that GHRH and GHRH-R loops involve in JEG-3 cell viability and apoptosis through Akt and eIF2α pathways.


Assuntos
Vilosidades Coriônicas/metabolismo , Fator de Iniciação 2 em Eucariotos/genética , Hormônio Liberador de Hormônio do Crescimento/genética , Proteínas Proto-Oncogênicas c-akt/genética , Receptores de Neuropeptídeos/genética , Receptores de Hormônios Reguladores de Hormônio Hipofisário/genética , Trofoblastos/metabolismo , Aborto Espontâneo/genética , Aborto Espontâneo/metabolismo , Aborto Espontâneo/patologia , Adulto , Apoptose , Estudos de Casos e Controles , Caspase 3/genética , Caspase 3/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Vilosidades Coriônicas/efeitos dos fármacos , Vilosidades Coriônicas/patologia , Cinamatos/farmacologia , Chaperona BiP do Retículo Endoplasmático , Fator de Iniciação 2 em Eucariotos/metabolismo , Feminino , Regulação da Expressão Gênica , Hormônio Liberador de Hormônio do Crescimento/metabolismo , Humanos , Gravidez , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Neuropeptídeos/metabolismo , Receptores de Hormônios Reguladores de Hormônio Hipofisário/metabolismo , Sermorelina/análogos & derivados , Sermorelina/antagonistas & inibidores , Sermorelina/farmacologia , Transdução de Sinais , Tioureia/análogos & derivados , Tioureia/farmacologia , Trofoblastos/efeitos dos fármacos , Trofoblastos/patologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
8.
Clin Exp Allergy ; 46(3): 491-503, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26610061

RESUMO

BACKGROUND: Shellfish allergy is one of the most common food hypersensitivities worldwide but allergen-specific immunotherapy for shellfish allergy is not yet available. We believe that T cell peptide-based immunotherapy holds the potential for modulating allergic responses without IgE cross-linking. OBJECTIVE: We sought to identify the immunodominant T cell epitopes of tropomyosin, the major shrimp allergen of Metapenaeus ensis (Met e 1), and to evaluate their therapeutic effects in a Balb/c mouse model of Met e 1 hypersensitivity. METHODS: T cell epitopes of Met e 1 were first identified based on the proliferation and cytokine responses of splenocytes isolated from Met e 1-sensitized Balb/c mice upon stimulation by 18 synthetic peptides that span the full-length Met e 1. The immunodominant T cell peptides identified were then fed orally to Met e 1-sensitized Balb/c mice twice a week for four weeks. Allergic responses, serological antibody levels, intestinal histology and systemic and local cytokine profiles were compared between the treated and the untreated groups. RESULTS: Six major Met e 1 T cell epitopes were identified. Mice treated with the T cell epitope peptide mixture demonstrated an amelioration of systemic allergic symptoms and a significant reduction in Th2-associated antibody and cytokine responses. These benefits were accompanied by a shift to a balanced Th1/Th2 response, induction of IgG2a antibodies possessing in vitro and in vivo blocking activities and the induction of regulatory T cell responses. CONCLUSIONS AND CLINICAL RELEVANCE: T cell epitope-based oral immunotherapy is effective in reducing allergic responses towards shrimp tropomyosin. This is a novel strategy for clinical management of shellfish allergy and is a model for mechanistic studies of oral immunotherapy.


Assuntos
Alérgenos/imunologia , Dessensibilização Imunológica , Epitopos de Linfócito T/imunologia , Hipersensibilidade Alimentar/imunologia , Penaeidae/imunologia , Sequência de Aminoácidos , Animais , Especificidade de Anticorpos/imunologia , Biomarcadores , Citocinas/metabolismo , Dessensibilização Imunológica/métodos , Modelos Animais de Doenças , Mapeamento de Epitopos , Epitopos de Linfócito T/química , Hipersensibilidade Alimentar/terapia , Humanos , Imunização , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Camundongos , Peptídeos/química , Peptídeos/imunologia , Proteínas/imunologia , Equilíbrio Th1-Th2
9.
Cell Death Dis ; 6: e1864, 2015 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-26313915

RESUMO

Ovarian high-grade serous carcinomas (HGSCs) and invasive low-grade serous carcinomas (LGSCs) are considered to be distinct entities. In particular, LGSCs are thought to arise from non-invasive serous borderline ovarian tumors (SBOTs) and show poor responsiveness to conventional chemotherapy. The pro-apoptotic effects of CD40 ligand (CD40L) have been demonstrated in HGSC, though the underlying mechanisms are not fully understood. Conversely, the therapeutic potential of the CD40L-CD40 system has yet to be evaluated in LGSC. We now show that CD40 protein is focally expressed on tumor cells in two of five primary LGSCs compared with no expression in eight primary SBOTs. Treatment with CD40L or agonistic CD40 antibody decreased the viability of LGSC-derived MPSC1 and VOA1312 cells, but not SBOT3.1 cells. Small interfering RNA (siRNA) targeting CD40 was used to show that it is required for these reductions in cell viability. CD40L treatment increased cleaved caspase-3 levels in MPSC1 cells though, surprisingly, neither pan-caspase inhibitor nor caspase-3 siRNA reversed or even attenuated CD40L-induced cell death. In addition, CD40-induced cell death was not affected by knockdown of the mitochondrial proteins apoptosis-inducing factor (AIF) and endonuclease G (EndoG). Interestingly, CD40L-induced cell death was blocked by necrostatin-1, an inhibitor of receptor-interacting protein 1 (RIP1), and attenuated by inhibitors of RIP3 (GSK'872) or MLKL (mixed lineage kinase domain-like; necrosulfonamide). Our results indicate that the upregulation of CD40 may be relatively common in LGSC and that CD40 activation induces RIP1-dependent, necroptosis-like cell death in LGSC cells.


Assuntos
Antígenos CD40/genética , Ligante de CD40/farmacologia , Cistadenocarcinoma Seroso/genética , Regulação Neoplásica da Expressão Gênica , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Neoplasias Ovarianas/genética , Proteínas de Ligação a RNA/genética , Acrilamidas/farmacologia , Anticorpos/farmacologia , Fator de Indução de Apoptose/antagonistas & inibidores , Fator de Indução de Apoptose/genética , Fator de Indução de Apoptose/metabolismo , Antígenos CD40/agonistas , Antígenos CD40/antagonistas & inibidores , Antígenos CD40/metabolismo , Ligante de CD40/genética , Ligante de CD40/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cistadenocarcinoma Seroso/metabolismo , Cistadenocarcinoma Seroso/patologia , Progressão da Doença , Endodesoxirribonucleases/antagonistas & inibidores , Endodesoxirribonucleases/genética , Endodesoxirribonucleases/metabolismo , Feminino , Humanos , Imidazóis/farmacologia , Indóis/farmacologia , Gradação de Tumores , Complexo de Proteínas Formadoras de Poros Nucleares/antagonistas & inibidores , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Proteínas de Ligação a RNA/antagonistas & inibidores , Proteínas de Ligação a RNA/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/antagonistas & inibidores , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Transdução de Sinais , Sulfonamidas/farmacologia
10.
Osteoporos Int ; 26(1): 261-72, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25160570

RESUMO

UNLABELLED: We investigated the densitometric and microstructural features of the distal radius in psoriatic arthritis (PsA) patients using high-resolution peripheral quantitative computed tomography. PsA patients have unique bone microstructural deficits, manifested as lower cortical bone density and higher cortical porosity, which are associated with a propensity to bone fragility. INTRODUCTION: The aim of this study was to investigate the densitometric, geometric, microstructural, and biomechanical features of the distal radius in psoriatic arthritis (PsA) patients. METHODS: This study cohort consisted of 53 PsA patients (24 males and 29 females), with an average age of 53.1 years and 53 gender- and age-matched controls. Areal bone mineral density (aBMD) of the hip, lumbar spine, and ultradistal radius was measured by dual-energy X-ray absorptiometry. High-resolution peripheral quantitative computed tomography (HR-pQCT) was performed at the distal radius to obtain measures of volumetric BMD (vBMD), microstructure, and derived biomechanical indices. RESULTS: There were no significant between-group differences in aBMD at the femoral neck, total hip, and ultradistal radius, while aBMD at the lumbar spine was significantly higher in patients. The only indices indicating compromised bone quality in PsA patients were related to cortical bone quality. Cortical vBMD were -3.8% significantly lower, while cortical pore volume, porosity index, and pore diameter were 108, 79.5, and 8.6%, respectively, significantly higher in patients. Cortical stress was marginally lower (-1.3%, p = 0.077) in patients with stress significantly more unevenly distributed (4.9%, p = 0.035). Endocortical perimeter and cortical pore volume were significantly higher in patients with vertebral fracture. Deficits in cortical bone quality were associated with indices of disease activity/severity and were more prominent in patients with type 2 diabetes mellitus or hypertension. CONCLUSIONS: There is an intertwined relationship between chronic inflammation, cardiovascular risk factors, and bone loss in PsA. PsA patients seem to have unique bone microstructural deficits which are associated with a propensity to bone fragility.


Assuntos
Artrite Psoriásica/fisiopatologia , Densidade Óssea/fisiologia , Inflamação/fisiopatologia , Osteoporose/etiologia , Rádio (Anatomia)/fisiopatologia , Absorciometria de Fóton/métodos , Adulto , Artrite Psoriásica/complicações , Estudos de Casos e Controles , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Humanos , Inflamação/complicações , Vértebras Lombares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Osteoporose/fisiopatologia , Fraturas por Osteoporose/etiologia , Fraturas por Osteoporose/fisiopatologia , Fatores de Risco , Tomografia Computadorizada por Raios X/métodos
12.
Environ Pollut ; 194: 188-195, 2014 11.
Artigo em Inglês | MEDLINE | ID: mdl-25150452

RESUMO

Fifteen polycyclic aromatic hydrocarbons (PAHs) in PM2.5 samples collected in five different cities (Hong Kong (HK), Guangzhou (GZ), Xiamen (XM), Xi'an (XA) and Beijing (BJ)) in China in the winter 2012-13 [corrected] were analyzed by gas chromatography-mass spectrometry. The biological effects of organic extracts were assayed using the human bronchial epithelial cells BEAS-2B. All sixteen priority PAHs can be found in the PM2.5 samples of XA and BJ, but not in HK, GZ and XM, demonstrating the differential spatial source and distribution of PAHs. Our results showed that the total PAHs ranged from 3.35 to 80.45 ng/m(3) air, leading by BJ, followed by XA, XM, GZ and HK. In the cell culture study, transcript levels of pro-inflammatory cytokine interleukin-6 (IL-6), CYP1A1 and CYP1B1 were found to be induced in the treatment. The cells exposed to extracts from XA and BJ demonstrated significant migratory activities, indicating a sign of increase of tumorigenicity.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Material Particulado/análise , Ar/análise , Poluição do Ar/análise , Poluição do Ar/estatística & dados numéricos , China , Cidades/estatística & dados numéricos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Hidrocarbonetos Policíclicos Aromáticos/análise , Estações do Ano
13.
Artigo em Inglês | MEDLINE | ID: mdl-25163818

RESUMO

OBJECTIVE: BYSH, a herbal formula, was evaluated for efficacy and safety in a pilot study for patients with advanced hormone refractory prostate cancer (HRPC). PATIENTS AND METHODS: The pilot study was designed as a single-center open-label trial. Patients with HRPC were treated with BYSH for 24 weeks. The primary end point was the changes in serum prostate-specific antigen (PSA) level. Safety parameters such as liver and renal functions were monitored during the study period. RESULTS: Ten patients were eligible for the study. Most of them had stable PSA levels while taking BYSH. However, at the end of the BYSH treatment, the level of PSA increased. The median survival from diagnosis of HRPC was 16.4 months. Liver and renal functions remained normal. BYSH was well tolerated and no patient reported adverse events during the study period. CONCLUSION: Although it is inappropriate to make a conclusion based on the pilot study results, the trend of improvement is obvious. Further investigations should be conducted to demonstrate its clinical benefits. We have also briefly reviewed some plant products which are patented and also available in market.


Assuntos
Extratos Vegetais/uso terapêutico , Antígeno Prostático Específico/sangue , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Patentes como Assunto , Projetos Piloto , Extratos Vegetais/efeitos adversos , Estudos Prospectivos , Neoplasias de Próstata Resistentes à Castração/patologia , Serenoa/química , Taxa de Sobrevida , Resultado do Tratamento
14.
Clin Exp Immunol ; 178(2): 253-61, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25041369

RESUMO

Treatment of primary biliary cirrhosis (PBC) has lagged behind that of other autoimmune diseases. In this study we have addressed the potential utility of immunotherapy using regulatory T cells (Treg ) to treat murine autoimmune cholangitis. In particular, we have taken advantage of our ability to produce portal inflammation and bile duct cell loss by transfer of CD8(+) T cells from the dominant negative form of transforming growth factor beta receptor type II (dnTGF-ßRII) mice to recombination-activating gene (Rag)1(-/-) recipients. We then used this robust established adoptive transfer system and co-transferred CD8(+) T cells from dnTGF-ßRII mice with either C57BL/6 or dnTGF-ßRII forkhead box protein 3 (FoxP3(+) ) T cells. Recipient mice were monitored for histology, including portal inflammation and intralobular biliary cell damage, and also included a study of the phenotypical changes in recipient lymphoid populations and local and systemic cytokine production. Importantly, we report herein that adoptive transfer of Treg from C57BL/6 but not dnTGF-ßRII mice significantly reduced the pathology of autoimmune cholangitis, including decreased portal inflammation and bile duct damage as well as down-regulation of the secondary inflammatory response. Further, to define the mechanism of action that explains the differential ability of C57BL/6 Treg versus dnTGF-ßRII Treg on the ability to down-regulate autoimmune cholangitis, we noted significant differential expression of glycoprotein A repetitions predominant (GARP), CD73, CD101 and CD103 and a functionally significant increase in interleukin (IL)-10 in Treg from C57BL/6 compared to dnTGF-ßRII mice. Our data reflect the therapeutic potential of wild-type CD4(+) FoxP3(+) Treg in reducing the excessive T cell responses of autoimmune cholangitis, which has significance for the potential immunotherapy of PBC.


Assuntos
Doenças Autoimunes/imunologia , Doenças Autoimunes/terapia , Colangite/imunologia , Colangite/terapia , Imunoterapia Adotiva , Linfócitos T Reguladores/imunologia , Animais , Doenças Autoimunes/patologia , Colangite/patologia , Citocinas/biossíntese , Modelos Animais de Doenças , Fatores de Transcrição Forkhead/metabolismo , Imunofenotipagem , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fenótipo , Baço/citologia , Baço/imunologia , Baço/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Reguladores/metabolismo
15.
Curr Mol Med ; 14(5): 673-89, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24894173

RESUMO

Thiol-containing antioxidant systems play an important role in regulating cellular redox homeostasis. Several anti-cancer agents act by targeting these systems by inducing the production of reactive oxygen species (ROS). Our earlier studies have shown that Eriocalyxin B (EriB), a diterpenoid isolated from Isodon eriocalyx, possesses anti-pancreatic tumour activities in vitro and in vivo. The present study further demonstrated that only thiol-containing antioxidants, N-acetylcysteine (NAC) or dithiothreitol (DTT), inhibited EriB-induced cytotoxicity and apoptosis. EriB suppressed the glutathione and thioredoxin antioxidant systems, thus increasing the intracellular ROS levels and regulating the MAPK, NFκB pathways. Treatment with EriB depleted the intracellular thiol-containing proteins in CAPAN-2 cells. In vivo studies also showed that EriB treatment (2.5 mg/kg) reduced the pancreatic tumour weights significantly in nude mice with increased superoxide levels. Taken together, our results shed important new light on the molecular mechanisms of EriB acting as an apoptogenic agent and its therapeutic potential for pancreatic cancer.


Assuntos
Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Diterpenos/farmacologia , Diterpenos/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Glutationa/metabolismo , Humanos , Masculino , Camundongos , Camundongos Nus , Espécies Reativas de Oxigênio/metabolismo , Neoplasias Pancreáticas
16.
Colorectal Dis ; 16(1): 2-14, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24330432

RESUMO

AIM: A systematic analysis was conducted of trials comparing the effectiveness of transanal endoscopic microsurgery (TEMS) with radical resection (RR) for T1 and T2 rectal cancer. METHOD: An electronic search was carried out of trials reporting the effectiveness of TEMS and RR in the treatment of T1 and T2 rectal cancers. RESULTS: Ten trials including 942 patients were retrieved. There was a trend toward a higher risk of local recurrence (odds ratio 2.78; 95% confidence interval 1.42, 5.44; z = 2.97; P < 0.003) and overall recurrence (P < 0.01) following TEMS compared with RR. The risk of distant recurrence, overall survival (odds ratio 0.90; 95% confidence interval 0.49, 1.66; z = 0.33; P = 0.74) and mortality was similar. TEMS was associated with a shorter operation time and hospital stay and a reduced risk of postoperative complications (P < 0.0001). The included studies, however, were significantly diverse in stage and grade of rectal cancer and the use of neoadjuvant chemoradiotherapy. CONCLUSION: Transanal endoscopic microsurgery appears to have clinically measurable advantages in patients with early rectal cancer. The studies included in this review do not allow firm conclusions as to whether TEMS is superior to RR in the management of early rectal cancer. Larger, better designed and executed prospective studies are needed to answer this question.


Assuntos
Adenocarcinoma/cirurgia , Microcirurgia/métodos , Proctoscopia/métodos , Neoplasias Retais/cirurgia , Reto/cirurgia , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Carcinoma/patologia , Carcinoma/cirurgia , Carcinoma/terapia , Humanos , Cirurgia Endoscópica por Orifício Natural , Terapia Neoadjuvante , Estadiamento de Neoplasias , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Resultado do Tratamento
17.
Clin Exp Immunol ; 174(3): 364-71, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23981074

RESUMO

While there have been significant advances in our understanding of the autoimmune responses and the molecular nature of the target autoantigens in primary biliary cirrhosis (PBC), unfortunately these data have yet to be translated into new therapeutic agents. We have taken advantage of a unique murine model of autoimmune cholangitis in which mice expressing a dominant negative form of transforming growth factor ß receptor II (dnTGFßRII), under the control of the CD4 promoter, develop an intense autoimmune cholangitis associated with serological features similar to human PBC. CD40-CD40 ligand (CD40L) is a major receptor-ligand pair that provides key signals between cells of the adaptive immune system, prompting us to determine the therapeutic potential of treating autoimmune cholangitis with anti-CD40L antibody (anti-CD40L; MR-1). Four-week-old dnTGFßRII mice were injected intraperitoneally with either anti-CD40L or control immunoglobulin (Ig)G at days 0, 2, 4 and 7 and then weekly until 12 or 24 weeks of age and monitored for the progress of serological and histological features of PBC, including rigorous definition of liver cellular infiltrates and cytokine production. Administration of anti-CD40L reduced liver inflammation significantly to 12 weeks of age. In addition, anti-CD40L initially lowered the levels of anti-mitochondrial autoantibodies (AMA), but these reductions were not sustained. These data indicate that anti-CD40L delays autoimmune cholangitis, but the effect wanes over time. Further dissection of the mechanisms involved, and defining the events that lead to the reduction in therapeutic effectiveness will be critical to determining whether such efforts can be applied to PBC.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Doenças Autoimunes/terapia , Ligante de CD40/imunologia , Colangite/terapia , Mitocôndrias/imunologia , Animais , Anticorpos Monoclonais/imunologia , Autoantígenos/imunologia , Doenças Autoimunes/imunologia , Autoimunidade/imunologia , Antígenos CD4/genética , Antígenos CD40/imunologia , Antígenos CD40/metabolismo , Ligante de CD40/metabolismo , Colangite/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Genótipo , Fígado/citologia , Fígado/metabolismo , Cirrose Hepática Biliar/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Regiões Promotoras Genéticas/genética , Receptores de Fatores de Crescimento Transformadores beta/imunologia
18.
Phytomedicine ; 20(7): 611-4, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23541215

RESUMO

Increasing prevalence of methicillin-resistant Staphylococcus aureus (MRSA) worldwide with limited therapeutic options is a growing public health concern. Natural products have been shown to possess antibacterial actions against MRSA. Flavonoids from natural products have been shown to possess antibacterial actions against MRSA by antagonizing its resistance mechanisms. Diosmin and diosmetin are natural flavonoids found in a variety of citrus fruits. The aim of this study was to investigate whether diosmin and diosmetin could inhibit the growth of MRSA and the in vitro enzymatic activity of a newly discovered MRSA drug target, pyruvate kinase (PK). By using a panel of MRSA strains with known resistant mechanisms, neither diosmin nor diosmetin was shown to possess direct antibacterial activities against all tested MRSA strains. However, in checkerboard assay, we found that diosmetin together with erythromycin, could synergistically inhibit the growth of ABC-pump overexpressed MRSA-RN4220/pUL5054, and time kill assay also showed that the antibacterial activities of diosmetin with erythromycin were bactericidal. Diosmetin was further shown to significantly suppress the MRSA PK activities in a dose dependent manner. In conclusion, the inhibition of MRSA PK by diosmetin could lead to a deficiency of ATP and affect the bacterial efflux pump which might contribute to the antibacterial actions of diosmetin against MRSA.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Antibacterianos/farmacologia , Eritromicina/farmacologia , Flavonoides/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Piruvato Quinase/antagonistas & inibidores , Trifosfato de Adenosina/metabolismo , Diosmina/farmacologia , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Staphylococcus aureus Resistente à Meticilina/metabolismo , Testes de Sensibilidade Microbiana
19.
Clin Exp Immunol ; 172(1): 95-103, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23480189

RESUMO

The phagocytic clearance of apoptotic cells is critical for tissue homeostasis; a number of non-professional phagocytic cells, including epithelial cells, can both take up and process apoptotic bodies, including the release of anti-inflammatory mediators. These observations are particularly important in the case of human intrahepatic biliary cells (HiBEC), because such cells are themselves a target of destruction in primary biliary cirrhosis, the human autoimmune disease. To address the apoptotic ability of HiBECs, we have focused on their ability to phagocytize apoptotic blebs from autologous HiBECs. In this study we report that HiBEC cells demonstrate phagocytic function from autologous HiBEC peers accompanied by up-regulation of the chemokines CCL2 [monocyte chemotactic protein-1 (MCP-1)] and CXCL8 [interleukin (IL)-8]. In particular, HiBEC cells express the phagocytosis-related receptor phosphatidylserine receptors (PSR), implying that HiBECs function through the 'eat-me' signal phosphatidylserine expressed by apoptotic cells. Indeed, although HiBEC cells acquire antigen-presenting cell (APC) function, they do not change the expression of classic APC function surface markers after engulfment of blebs, both with and without the presence of Toll-like receptor (TLR) stimulation. These results are important not only for understanding of the normal physiological function of HiBECs, but also explain the inflammatory potential and reduced clearance of HiBEC cells following the inflammatory cascade in primary biliary cirrhosis.


Assuntos
Apoptose , Ductos Biliares Intra-Hepáticos/imunologia , Células Epiteliais/imunologia , Macrófagos/imunologia , Fagocitose , Animais , Ácidos e Sais Biliares/farmacologia , Ductos Biliares Intra-Hepáticos/citologia , Células Cultivadas , Quimiocina CCL2/genética , Quimiocina CCL2/imunologia , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Expressão Gênica , Humanos , Interleucina-8/genética , Interleucina-8/imunologia , Lipopolissacarídeos/farmacologia , Cirrose Hepática Biliar/imunologia , Cirrose Hepática Biliar/patologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Camundongos , Fosfatidilserinas/imunologia , Fosfatidilserinas/metabolismo , Poli I-C/farmacologia , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/imunologia , Transdução de Sinais , Receptores Toll-Like/genética , Receptores Toll-Like/imunologia , Regulação para Cima
20.
Oncogene ; 32(8): 1041-9, 2013 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-22508482

RESUMO

Loss of the cell adhesion protein E-cadherin increases the invasive capability of ovarian cancer cells. We have previously shown that epidermal growth factor (EGF) downregulates E-cadherin and induces ovarian cancer cell invasion through the H(2)O(2)/p38 MAPK-mediated upregulation of the E-cadherin transcriptional repressor Snail. However, the molecular mechanisms underlying the EGF-induced downregulation of E-cadherin are not fully understood. In the current study, we demonstrated that treatment of two ovarian cancer cell lines, SKOV3 and OVCAR5, with EGF induced the expression of the transcription factor Egr-1, and this induction was abolished by small interfering RNA (siRNA)-mediated depletion of the EGF receptor. EGF-induced Egr-1 expression required the activation of the ERK1/2 and PI3K/Akt signaling pathways and was unrelated to EGF-induced H(2)O(2) production and activation of the p38 MAPK pathway. Moreover, depletion of Egr-1 with siRNA abolished the EGF-induced downregulation of E-cadherin and increased cell invasion. Interestingly, siRNA depletion of Egr-1 attenuated the EGF-induced expression of Slug, but not that of Snail. Moreover, chromatin immunoprecipitation (ChIP) analysis showed that Slug is a target gene of Egr-1. These results provide evidence that Egr-1 is a mediator that is involved in the EGF-induced downregulation of E-cadherin and increased cell invasion. Our results also demonstrate that EGF activates two independent signaling pathways, which are the H(2)O(2)/p38 MAPK-mediated upregulation of Snail expression and the Egr-1-mediated upregulation of Slug expression. These two signaling pathways contribute to the EGF-induced downregulation of E-cadherin, which subsequently increases the invasive capability of ovarian cancer cells.


Assuntos
Caderinas/biossíntese , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Fator de Crescimento Epidérmico/farmacologia , Neoplasias Ovarianas/metabolismo , Fatores de Transcrição/metabolismo , Caderinas/genética , Caderinas/metabolismo , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Proteína 1 de Resposta de Crescimento Precoce/biossíntese , Proteína 1 de Resposta de Crescimento Precoce/genética , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Ovarianas/genética , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Fatores de Transcrição da Família Snail , Fatores de Transcrição/genética , Transfecção
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