Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
1.
Diabetes ; 72(10): 1433-1445, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37478155

RESUMO

Altered endoplasmic reticulum (ER) Ca2+ signaling has been linked with ß-cell dysfunction and diabetes development. Store-operated Ca2+ entry replenishes ER Ca2+ through reversible gating of plasma membrane Ca2+ channels by the ER Ca2+ sensor, stromal interaction molecule 1 (STIM1). For characterization of the in vivo impact of STIM1 loss, mice with ß-cell-specific STIM1 deletion (STIM1Δß mice) were generated and challenged with high-fat diet. Interestingly, ß-cell dysfunction was observed in female, but not male, mice. Female STIM1Δß mice displayed reductions in ß-cell mass, a concomitant increase in α-cell mass, and reduced expression of markers of ß-cell maturity, including MafA and UCN3. Consistent with these findings, STIM1 expression was inversely correlated with HbA1c levels in islets from female, but not male, human organ donors. Mechanistic assays demonstrated that the sexually dimorphic phenotype observed in STIM1Δß mice was due, in part, to loss of signaling through the noncanonical 17-ß estradiol receptor (GPER1), as GPER1 knockdown and inhibition led to a similar loss of expression of ß-cell maturity genes in INS-1 cells. Together, these data suggest that STIM1 orchestrates pancreatic ß-cell function and identity through GPER1-mediated estradiol signaling. ARTICLE HIGHLIGHTS: Store-operated Ca2+ entry replenishes endoplasmic reticulum (ER) Ca2+ through reversible gating of plasma membrane Ca2+ channels by the ER Ca2+ sensor, stromal interaction molecule 1 (STIM1). ß-Cell-specific deletion of STIM1 results in a sexually dimorphic phenotype, with ß-cell dysfunction and loss of identity in female but not male mice. Expression of the noncanonical 17-ß estradiol receptor (GPER1) is decreased in islets of female STIM1Δß mice, and modulation of GPER1 levels leads to alterations in expression of ß-cell maturity genes in INS-1 cells.


Assuntos
Canais de Cálcio , Proteínas de Membrana , Animais , Camundongos , Feminino , Humanos , Proteínas de Membrana/metabolismo , Canais de Cálcio/metabolismo , Molécula 1 de Interação Estromal/genética , Molécula 1 de Interação Estromal/metabolismo , Cálcio/metabolismo , Receptores de Estradiol/metabolismo , Receptor alfa de Estrogênio/metabolismo , Sinalização do Cálcio , Proteínas de Ligação ao GTP/metabolismo
2.
Int J Mol Sci ; 24(8)2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37108825

RESUMO

Kimura's disease (KD) is a rare lymphoproliferative fibroinflammatory disorder that commonly affects the subcutaneous tissue and lymph nodes of the head and neck. The condition is a reactive process involving T helper type 2 cytokines. Concurrent malignancies have not been described. Differential diagnosis with lymphoma can be challenging without tissue biopsy. Here, we present the first reported case of coexisting KD and eosinophilic nodular sclerosis Hodgkin lymphoma of the right cervical lymphatics in a 72-year-old Taiwanese man.


Assuntos
Hiperplasia Angiolinfoide com Eosinofilia , Doença de Hodgkin , Doença de Kimura , Masculino , Humanos , Idoso , Doença de Kimura/diagnóstico , Doença de Kimura/patologia , Hiperplasia Angiolinfoide com Eosinofilia/complicações , Hiperplasia Angiolinfoide com Eosinofilia/diagnóstico , Hiperplasia Angiolinfoide com Eosinofilia/patologia , Doença de Hodgkin/complicações , Doença de Hodgkin/diagnóstico , Doença de Hodgkin/patologia , Esclerose/patologia , Linfonodos/patologia , Diagnóstico Diferencial , Doenças Raras/diagnóstico
3.
Front Med (Lausanne) ; 9: 1069102, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36643844

RESUMO

Introduction: Kimura's disease (KD) is an uncommon lymphoproliferative fibroinflammatory disorder. Patients present with head and neck subcutaneous nodules with or without lymphadenopathy. Peripheral blood eosinophilia and elevated serum immunoglobulin E (IgE) levels are typical. This study was designed to delineate the clinicopathological features, pattern of care, and disease course of 23 Taiwanese patients with KD. Methods: We retrospectively analyzed the clinical data of 23 consecutive cases (16 male and 7 female; age at diagnosis: 12-77 years) of KD diagnosed at our institution from 2015 to 2020. Results: The median time from presentation to diagnosis was 1 month. Twenty-one patients presented with unilateral or bilateral head and neck masses. The remaining two presented with right flank and right arm lesions, respectively. Peripheral blood eosinophilia was observed in nine, and elevated IgE levels were observed in four. All were diagnosed using either excisional or core-needle biopsy. Seven patients underwent fine needle aspiration without a diagnostic yield. Salivary gland and lymph node involvement was observed in three and seven patients, respectively. Most lesions showed tissue eosinophilia (100%) and florid follicular hyperplasia (78.26%). Three cases had histological KD-IgG4-RD overlap and three had comorbid IgG4-RD were recognized. Thirteen patients underwent surgical resection, one received adjuvant therapy, and two received prednisolone monotherapy. Conclusion: KD should be considered in patients with subcutaneous masses, eosinophilia, and elevated IgE levels. Biopsy remains the gold standard of diagnosis. Increased recruitment of IgG4+ plasma cells is a common feature. Consideration of IgG4-RD in all KD patients may be prudent.

4.
Am J Pathol ; 191(2): 353-367, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33159889

RESUMO

Utilization of proper preclinical models accelerates development of immunotherapeutics and the study of the interplay between human malignant cells and immune cells. Lysosomal acid lipase (LAL) is a critical lipid hydrolase that generates free fatty acids and cholesterol. Ablation of LAL suppresses immune rejection and allows growth of human lung cancer cells in lal-/- mice. In the lal-/- lymph nodes, the percentages of both T- and B-regulatory cells (Tregs and Bregs, respectively) are increased, with elevated expression of programmed death-ligand 1 and IL-10, and decreased expression of interferon-γ. Levels of enzymes in the glucose and glutamine metabolic pathways are elevated in Tregs and Bregs of the lal-/- lymph nodes. Pharmacologic inhibitor of pyruvate dehydrogenase, which controls the transition from glycolysis to the citric acid cycle, effectively reduces Treg and Breg elevation in the lal-/- lymph nodes. Blocking the mammalian target of rapamycin or reactivating peroxisome proliferator-activated receptor γ, an LAL downstream effector, reduces lal-/- Treg and Breg elevation and PD-L1 expression in lal-/- Tregs and Bregs, and improves human cancer cell rejection. Treatment with PD-L1 antibody also reduces Treg and Breg elevation in the lal-/- lymph nodes and improves human cancer cell rejection. These observations conclude that LAL-regulated lipid metabolism is essential to maintain antitumor immunity.


Assuntos
Linfócitos B Reguladores/imunologia , Neoplasias Experimentais/imunologia , Esterol Esterase/deficiência , Linfócitos T Reguladores/imunologia , Evasão Tumoral/imunologia , Animais , Modelos Animais de Doenças , Xenoenxertos , Homeostase/imunologia , Humanos , Linfonodos/imunologia , Camundongos , Camundongos Knockout , Transplante de Neoplasias , Esterol Esterase/imunologia
5.
Mol Metab ; 37: 100975, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32283079

RESUMO

OBJECTIVES: Epidemiological studies indicate that first- and second-hand cigarette smoke (CS) exposure are important risk factors for the development of type 2 diabetes (T2D). Additionally, elevated diabetes risk has been reported to occur within a short period of time after smoking cessation, and health risks associated with smoking are increased when combined with obesity. At present, the mechanisms underlying these associations remain incompletely understood. The objective of this study was to test the impact of CS exposure on pancreatic ß-cell function using rodent and in vitro models. METHODS: Beginning at 8 weeks of age, C57BL/6 J mice were concurrently fed a high-fat diet (HFD) and exposed to CS for 11 weeks, followed by an additional 11 weeks of smoking cessation with continued HFD. Glucose tolerance testing was performed during CS exposure and during the cessation period. Cultured INS-1 ß-cells and primary islets were exposed ex vivo to CS extract (CSE), and ß-cell function and viability were tested. Since CS increases ceramide accumulation in the lung and these bioactive sphingolipids have been implicated in pancreatic ß-cell dysfunction in diabetes, islet and ß-cell sphingolipid levels were measured in islets from CS-exposed mice and in CSE-treated islets and INS-1 cells using liquid chromatography-tandem mass spectrometry. RESULTS: Compared to HFD-fed, ambient air-exposed mice, HFD-fed and CS-exposed mice had reduced weight gain and better glucose tolerance during the active smoking period. Following smoking cessation, CS-mice exhibited rapid weight gain and had accelerated worsening of their glucose tolerance. CS-exposed mice had higher serum proinsulin/insulin ratios, indicative of ß-cell dysfunction, significantly lower ß-cell mass (p = 0.017), reduced ß-cell proliferation (p = 0.006), and increased islet ceramide content compared to non-smoking control mice. Ex vivo exposure of isolated islets to CSE was sufficient to increase islet ceramide levels, which was correlated with reduced insulin gene expression and glucose-stimulated insulin secretion, and increased ß-cell oxidative and endoplasmic reticulum (ER) stress. Treatment with the antioxidant N-acetylcysteine markedly attenuated the effects of CSE on ceramide levels, restored ß-cell function and survival, and increased cyclin D2 expression, while also reducing activation of ß-cell ER and oxidative stress. CONCLUSIONS: Our results indicate that CS exposure leads to impaired insulin production, processing, secretion and reduced ß-cell viability and proliferation. These effects were linked to increased ß-cell oxidative and ER stress and ceramide accumulation. Mice fed HFD continued to experience detrimental effects of CS exposure even during smoking cessation. Elucidation of the mechanisms by which CS exposure impairs ß-cell function in synergy with obesity will help design therapeutic and preventive interventions for both active and former smokers.


Assuntos
Ceramidas/metabolismo , Células Secretoras de Insulina/efeitos dos fármacos , Fumar Tabaco/efeitos adversos , Animais , Glicemia/metabolismo , Proliferação de Células/efeitos dos fármacos , Diabetes Mellitus Tipo 2/metabolismo , Dieta Hiperlipídica , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Estresse do Retículo Endoplasmático/fisiologia , Glucose/metabolismo , Teste de Tolerância a Glucose , Insulina/metabolismo , Resistência à Insulina/fisiologia , Secreção de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/complicações , Obesidade/metabolismo , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Produtos do Tabaco/efeitos adversos , Aumento de Peso
6.
J Immunol ; 202(3): 991-1002, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30567728

RESUMO

Early detection of lung cancer offers an important opportunity to decrease mortality while it is still treatable and curable. Thirteen secretory proteins that are Stat3 downstream gene products were identified as a panel of biomarkers for lung cancer detection in human sera. This panel of biomarkers potentially differentiates different types of lung cancer for classification. Among them, the transthyretin (TTR) concentration was highly increased in human serum of lung cancer patients. TTR concentration was also induced in the serum, bronchoalveolar lavage fluid, alveolar type II epithelial cells, and alveolar myeloid cells of the CCSP-rtTA/(tetO)7-Stat3C lung tumor mouse model. Recombinant TTR stimulated lung tumor cell proliferation and growth, which were mediated by activation of mitogenic and oncogenic molecules. TTR possesses cytokine functions to stimulate myeloid cell differentiation, which are known to play roles in tumor environment. Further analyses showed that TTR treatment enhanced the reactive oxygen species production in myeloid cells and enabled them to become functional myeloid-derived suppressive cells. TTR demonstrated a great influence on a wide spectrum of endothelial cell functions to control tumor and immune cell migration and infiltration. TTR-treated endothelial cells suppressed T cell proliferation. Taken together, these 13 Stat3 downstream inducible secretory protein biomarkers potentially can be used for lung cancer diagnosis, classification, and as clinical targets for lung cancer personalized treatment if their expression levels are increased in a given lung cancer patient in the blood.


Assuntos
Células Endoteliais/imunologia , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/imunologia , Pré-Albumina/imunologia , Células Epiteliais Alveolares/imunologia , Animais , Biomarcadores Tumorais/sangue , Líquido da Lavagem Broncoalveolar/química , Movimento Celular , Proliferação de Células , Modelos Animais de Doenças , Humanos , Neoplasias Pulmonares/classificação , Melanoma Experimental , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Células Mieloides/imunologia , Neoplasias Experimentais/imunologia , Pré-Albumina/farmacologia , Proteínas Recombinantes/farmacologia , Fator de Transcrição STAT3/genética
7.
Int J Mol Sci ; 17(8)2016 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-27483249

RESUMO

Peroxisome proliferator-activated receptor γ (PPARγ) is a ligand-activated nuclear receptor that regulates cellular lipid and glucose metabolism and also plays an inhibitory role in various cancers. However, the role of PPARγ in hepatocellular carcinoma (HCC) remains controversial. This study aimed to investigate the prognostic value of PPARγ in HCC and its role in inhibiting tumor progression, namely, HCC cell growth, migration, and angiogenesis. Immunohistochemical PPARγ staining was examined in 83 HCC specimens to investigate the clinicopathological correlations between PPARγ expression and various parameters. The functional role of PPARγ was determined via PPARγ overexpression and knockdown in HCC cells. Patients with low HCC tissue PPARγ expression were significantly younger (p = 0.006), and exhibited more tumor numbers (p = 0.038), more macroscopic vascular invasion (MVI) (p = 0.008), and more advanced TNM (size of primary tumor, number of regional lymph nodes, and distant metastasis) stages at diagnosis (p = 0.013) than patients with high HCC tissue PPARγ expression. PPARγ knockdown increased HCC cell growth, migration, and angiogenesis, while PPARγ overexpression reduced HCC cell growth, migration, and angiogenesis. These results suggest that low PPARγ expression is an independent predictor of more MVI in HCC patients. PPARγ contributes to the suppression of HCC cell growth, migration, and angiogenesis. Therefore, PPARγ may be a therapeutic target in HCC patients.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Neovascularização Patológica/patologia , PPAR gama/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose , Western Blotting , Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/metabolismo , Movimento Celular , Proliferação de Células , Feminino , Humanos , Técnicas Imunoenzimáticas , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/metabolismo , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , PPAR gama/antagonistas & inibidores , PPAR gama/genética , Prognóstico , RNA Interferente Pequeno/genética , Taxa de Sobrevida , Células Tumorais Cultivadas
8.
Arch Virol ; 160(12): 3021-35, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26392283

RESUMO

The objective of the present study was to determine if chicken melanoma-differentiation-associated gene 5 (MDA5) senses infectious bursal disease virus infection to induce innate immunity that bridges to adaptive immunity. During IBDV infection in HD11 cells, IBDV titers and RNA loads increased up to 3.4 × 10(7) plaque-forming units (PFU)/mL and 1114 ng/µL, respectively, at 24 hours postinfection (hpi). IBDV infection in HD11 cells induced significantly upregulated (p < 0.05) expression levels of chicken MDA5 (59-fold), interferon-ß (IFN-ß) (693-fold), dsRNA-dependent protein kinase (PKR) (4-fold), 2', 5'-oligoadenylate synthetase (OAS) (286-fold), myxovirus resistance gene (Mx) (22-fold), interleukin-1ß (IL-1ß) (5-fold), IL-6 (146-fold), IL-8 (4-fold), IL-10 (4-fold), inducible nitric oxide synthase (iNOS) (15-fold), and major histocompatibility complex class I (MHC class I) (4-fold). Nitric oxide production in the culture supernatants increased significantly (p < 0.05) up to 6.5 µM at 24 hpi. The expressed chMDA5 and IBDV-derived dsRNA were localized in the cytoplasm of HD11 cells during IBDV infection. ChMDA5-knockdown HD11 cells had significantly higher (p < 0.05) IBDV RNA loads at 24 hpi and significantly lower (p < 0.05) nitric oxide production and expression levels of chicken MDA5, IFN-ß, PKR, OAS, Mx, IL-1ß, IL-6, IL-8, IL-12(p40), IL-18, IL-10, iNOS, MHC class I and CD86 at 24 hpi. In addition, chMDA5 overexpression in HD11 cells resulted in significantly reduced (p < 0.05) IBDV titers and RNA loads and significantly increased (p < 0.05) nitric oxide production at 16 and 24 hpi. It also resulted in significantly higher (p < 0.05) expression levels of chicken MDA5, IFN-ß, PKR, OAS, Mx, IL-1ß, IL-6, IL-8, IL-12(p40), IL-10 and iNOS at 2 hpi. In conclusion, the results indicate that chMDA5 senses IBDV infection in chicken macrophages, and this is associated with IBDV-induced expression of IFN-ß and initiation of an innate immune response that in turn activates the adaptive immune response and limits IBDV replication.


Assuntos
Imunidade Adaptativa , Infecções por Birnaviridae/veterinária , RNA Helicases DEAD-box/imunologia , Imunidade Inata , Vírus da Doença Infecciosa da Bursa/fisiologia , Macrófagos/imunologia , Doenças das Aves Domésticas/imunologia , Animais , Infecções por Birnaviridae/genética , Infecções por Birnaviridae/imunologia , Infecções por Birnaviridae/virologia , Galinhas , Citocinas/genética , Citocinas/imunologia , RNA Helicases DEAD-box/genética , Vírus da Doença Infecciosa da Bursa/genética , Macrófagos/enzimologia , Macrófagos/virologia , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/imunologia , Doenças das Aves Domésticas/enzimologia , Doenças das Aves Domésticas/virologia
9.
Oncol Rep ; 34(1): 439-46, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25954999

RESUMO

Krüppel-like factor 4 (KLF4) plays important roles in development, stemness and tumorigenesis; however limited information is available on the detailed function of KLF4 in hepatocellular carcinoma (HCC). The objective of the present study was to examine the functional roles of KLF4 in the metastasis of HCC cells. KLF4 was overexpressed and knocked down by lentiviral transduction method in highly metastatic HCC cells. KLF4 overexpression in HCC cells led to inhibition of cell migration and invasion. These inhibitory effects were associated with the upregulation of tissue inhibitors of metalloproteinase (TIMP)-1 and TIMP-2 by KLF4. Treatment with recombinant TIMP-1 decreased the migratory ability of HCC cells. Moreover, myeloperoxidase (MPO)-TIMP-1/TIMP-2 inactivator counteracted the KLF4-induced inhibition of cell migration/invasion. Consistently, KLF4 knockdown in HCC cells downregulated TIMP-1 and TIMP-2 expression, consequently promoting cell migration and invasion. Furthermore, we found that KLF4 regulated E-cadherin and epithelial-mesenchymal transition (EMT)-related proteins such as snail, vimentin and Bmi1 to modulate the cell migration ability. These results together demonstrated for the first time that KLF4 plays an important role in inhibiting the aggressiveness of HCC cells via upregulation of TIMP-1 and TIMP-2.


Assuntos
Carcinoma Hepatocelular/patologia , Fatores de Transcrição Kruppel-Like/metabolismo , Neoplasias Hepáticas/patologia , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Carcinoma Hepatocelular/metabolismo , Movimento Celular , Transição Epitelial-Mesenquimal , Células HEK293 , Células Hep G2 , Humanos , Fator 4 Semelhante a Kruppel , Neoplasias Hepáticas/metabolismo , Invasividade Neoplásica , Regulação para Cima
10.
Ecotoxicol Environ Saf ; 113: 362-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25531833

RESUMO

Cigarette butts (CBs) littering is not just an unsightly nuisance but also a public health problem, because chemicals contained in cigarettes can leach into aquatic environments and pose a risk to the health of humans and wildlife. However, this risk is largely unrecognized or ignored by the public, and toxicological evidence of CBs is scarce. Therefore, we used medaka embryos (Oryzias latipes) to explore developmental toxicity of CBs. The embryos were exposed to various concentrations of leachates from smoked and unsmoked cigarette tobacco (ST and UST) and filters (SF and USF), and observed from 1 to 3 days post-fertilization. The images were recorded and several developmental endpoints analyzed. The values from these endpoints were then used to calculate the Integrated Biomarker Response and evaluate overall effects of the leachates. Some of the embryos were allowed to hatch, and the hatchlings were tested for anxiety-like behavior. Our results showed that low concentrations of the leachates from ST, UST, and SF raised the heart rate, accelerated development, and changed behavior, while high concentrations lowered the heart rate, suppressed development, and increased mortality. The lowest observed effect concentration for the leachates was ≤0.2piece (pc)/L. The USF leachate had no effect at the concentration of 20pc/L. Developmental toxicity of the leachates was ranked as: ST>UST>SF>USF. This study has demonstrated for the first time that CB leachates affect fish development, and provided toxicological evidence to better assess ecological impacts of CBs.


Assuntos
Produtos do Tabaco/toxicidade , Poluentes da Água/toxicidade , Animais , Oryzias/embriologia
11.
Arch Virol ; 159(7): 1671-86, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24452668

RESUMO

The objective of the present study was to determine if chicken melanoma differentiation-associated gene 5 (MDA5) senses infectious bursal disease virus (IBDV) infection to initiate and amplify an innate immune response in the chicken MDA5 (chMDA5) signaling pathway. Chicken embryo fibroblast DF-1 cells were infected with IBDV LP1 at a multiplicity of infection (MOI) of 0.5 or 10. In addition, knockdown and overexpression of chMDA5 were performed by transfecting DF-1 cells with chMDA5-targeting small interfering RNA (siRNA) or chMDA5-expressing DNA. The transfected cells were infected with IBDV LP1 at an MOI of 10. Cell culture supernatants and lysates were collected at 2, 8, 16 and 24 hours postinfection (hpi) for IBDV titer determination and RNA extraction, respectively. IBDV RNA loads and mRNA expression levels of chicken MDA5, interferon-ß (IFN-ß) promoter stimulator 1 (IPS-1), interferon regulatory factor-3 (IRF-3), IFN-ß, double-stranded RNA-dependent protein kinase (PKR), 2',5'-oligoadenylate synthetase (OAS), myxovirus resistance gene (Mx), and major histocompatibility complex class I (MHC class I) were determined by real-time RT-PCR. The IBDV titer increased up to 1.4 × 10(7) plaque-forming units (PFU)/mL at 24 hpi, and the IBDV RNA load reached 464 ng/µL at 24 hpi. The mRNA expression levels of chicken MDA5, IRF-3, IFN-ß, PKR, OAS, Mx and MHC class I in IBDV-infected DF-1 cells exhibited significant (p < 0.05) upregulation up to 906-, 199-, 26,310-, 12-, 66,144-, 64,039- and 33-fold, respectively. Expressed chMDA5 from transfection and double-stranded RNA from IBDV infection were localized or colocalized in the cytoplasm of DF-1 cells at 16 hpi. When chMDA5 was knocked down in DF-1 cells, IBDV titers and RNA loads were significantly higher (p < 0.05) than those in DF-1 cells without chMDA5 knockdown at 24 hpi. The expression levels of chicken MDA5, IRF-3, IFN-ß and MHC class I in chMDA5-knockdown DF-1 cells were significantly lower (p < 0.05) at 16 and 24 hpi. DF-1 cells overexpressing chMDA5 by transfection with chMDA5 expressing DNA had significantly lower (p < 0.05) IBDV titers and RNA loads at 16 and 24 hpi and showed significantly higher (p < 0.05) expression of chicken MDA5, IRF-3, IFN-ß, PKR, OAS, Mx and MHC class I at 2 hpi. The results indicated that chicken MDA5 recognized IBDV infection and that this interaction resulted in the activation of chMDA5-related innate immune genes and upregulation of chicken MHC class I.


Assuntos
Infecções por Birnaviridae/veterinária , RNA Helicases DEAD-box/metabolismo , Fibroblastos/virologia , Vírus da Doença Infecciosa da Bursa/imunologia , Animais , Infecções por Birnaviridae/imunologia , Infecções por Birnaviridae/virologia , Linhagem Celular , Embrião de Galinha , Regulação da Expressão Gênica/imunologia , Técnicas de Silenciamento de Genes , Imunidade Humoral , Imunidade Inata , Fator Regulador 3 de Interferon/metabolismo , Interferon beta/metabolismo , RNA de Cadeia Dupla , RNA Viral
12.
Comp Immunol Microbiol Infect Dis ; 35(4): 335-43, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22459580

RESUMO

The present study was undertaken to identify and characterize chicken melanoma differentiation-associated gene 5 (MDA5) from alternative translation initiation. The alternatively translated chicken MDA5 had an open reading frame of 3309 base pairs, shorter than the predicted chicken MDA5 sequence by 549 base pairs and longer than the recently published chicken MDA5 (GU570144) by 303 base pairs. The domain architecture was conserved among MDA5 molecules from various vertebrates. The alternatively translated chicken MDA5 shared high genetic identity to zebrafinch MDA5, but not to fish or mammalian MDA5. Various concentrations of chicken MDA5 transcripts were detected in different chicken tissues, with the highest concentration found in the intestine (1.4×10(10)copy/mg tissue). Chicken interferon (IFN-ß) expression was dependent on the dose of pCDNA3.1-MDA5-long transfection in DF1 cells without double-stranded RNA stimulation. DF1 cells transfected with polyinosinic-polycytidylic acid (poly(I:C)) had significantly (p<0.05) increased fold changes in chicken MDA5 and IFN-ß mRNA expression as compared to those in the controls. DF1 cells incubated with poly(I:C) did not have significant (p>0.05) changes in mRNA expression of chicken MDA5 and IFN-ß. Chicken MDA5 mRNA level did not change significantly (p>0.05) in DF1 cells treated with imiquimod or bacterial DNA. The results indicate that although chicken MDA5 is phylogenetically different from mammalian MDA5, the domain architecture remains conserved. Chicken MDA5 can be detected in various tissues and functions to signal the activation of chicken IFN-ß when overexpressing or being stimulated by poly(I:C).


Assuntos
Proteínas Aviárias/genética , Iniciação Traducional da Cadeia Peptídica , RNA Helicases/genética , Aminoquinolinas/farmacologia , Animais , Proteínas Aviárias/metabolismo , Linhagem Celular , Galinhas , Imiquimode , Imunidade Inata , Interferon beta/biossíntese , Interferon beta/genética , Fases de Leitura Aberta , Especificidade de Órgãos , Filogenia , Poli I-C/genética , Estrutura Terciária de Proteína , RNA Helicases/metabolismo , RNA Mensageiro/biossíntese , Transfecção
13.
Hepatogastroenterology ; 52(64): 1168-71, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16001654

RESUMO

BACKGROUND/AIMS: Bile leakage after hepatic resection can cause septic complications and mortality. This study evaluated the risk factors associated with postoperative bile leakage in hepatocellular carcinoma patients. METHODOLOGY: Between July 1991 and December 2000, 605 consecutive hepatocellular carcinoma patients who underwent hepatic resection were enrolled. Risk factors associated with postoperative bile leakage were examined, with 38 clinicopathological variables being analyzed. Data were collected prospectively and analyzed retrospectively. RESULTS: Bile leakage developed in 35 (5.8%) of 605 patients. When compared with patients without bile leakage, those with bile leakage had higher risk for concomitant morbidities (54.3% vs. 29.2%, P=0.002), postoperative mortality (8.6% vs. 2.6%, P=0.045), and a prolonged postoperative hospital stay (29 days vs. 14 days, P<0.001). The bile leakage rate of centrally located tumors (9.4%) was significantly higher than that of peripherally located tumors (3.5%; P=0.002). The bile leakage rate of patients with preoperative chemoembolization (13.8%) was significantly higher than those without chemoembolization (4.9%; P=0.004). Stepwise logistic regression analysis identified preoperative chemoembolization (OR=3.274, P=0.005) and tumor(s) being centrally located (OR=2.927, P=0.003) as the independent predictors of development of bile leakage. CONCLUSIONS: For HCC patients, preoperative chemoembolization and tumor(s) with central location are risk factors for post-hepatectomy bile leakage. As bile leakage can cause septic complications and liver failure, careful surgical procedures and use of preventive measures are necessary, especially in patients with high risk factors.


Assuntos
Bile , Carcinoma Hepatocelular/cirurgia , Hepatectomia/efeitos adversos , Neoplasias Hepáticas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibióticos Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Quimioembolização Terapêutica , Epirubicina/administração & dosagem , Feminino , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Complicações Pós-Operatórias , Estudos Retrospectivos , Fatores de Risco
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA