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1.
JCI Insight ; 4(20)2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31557133

RESUMO

Kabuki syndrome 1 (KS1) is a Mendelian disorder of the epigenetic machinery caused by mutations in the gene encoding KMT2D, which methylates lysine 4 on histone H3 (H3K4). KS1 is characterized by intellectual disability, postnatal growth retardation, and distinct craniofacial dysmorphisms. A mouse model (Kmt2d+/ßGeo) exhibits features of the human disorder and has provided insight into other phenotypes; however, the mechanistic basis of skeletal abnormalities and growth retardation remains elusive. Using high-resolution micro-CT, we show that Kmt2d+/ßGeo mice have shortened long bones and ventral bowing of skulls. In vivo expansion of growth plates within skulls and long bones suggests disrupted endochondral ossification as a common disease mechanism. Stable chondrocyte cell lines harboring inactivating mutations in Kmt2d exhibit precocious differentiation, further supporting this mechanism. A known inducer of chondrogenesis, SOX9, and its targets show markedly increased expression in Kmt2d-/- chondrocytes. By transcriptome profiling, we identify Shox2 as a putative KMT2D target. We propose that decreased KMT2D-mediated H3K4me3 at Shox2 releases Sox9 inhibition and thereby leads to enhanced chondrogenesis, providing a potentially novel and plausible explanation for precocious chondrocyte differentiation. Our findings provide insight into the pathogenesis of growth retardation in KS1 and suggest therapeutic approaches for this and related disorders.

2.
Yi Chuan ; 41(8): 669-676, 2019 Aug 20.
Artigo em Chinês | MEDLINE | ID: mdl-31447418

RESUMO

ß-thalassemia (ß-thal) is a fatal and disabling inherited blood disorder with diverse phenotypes. The same or similar genotype of ß-thal can manifest variable clinical severities. It is the hotspot and emphasis in the field of hematopathy and genetic diseases to explore genetic modifiers that influence the phenotype of ß-thal. This review illustrates the deteriorating and amelioratig modifiers from two aspects: genotypes of α-globin and quantitative trait locus of fetal hemoglobin (Hb F). Variations of transcription factors which reactive the γ-globin gene expression and ß-globin cluster cis-acting elements were introduced emphatically. Finally, clinical applications and future development prospects of ß-thal genetic modifiers are introduced by examples.


Assuntos
Talassemia beta/genética , Hemoglobina Fetal/genética , Genótipo , Humanos , Fenótipo , Fatores de Transcrição/genética , alfa-Globinas/genética , Globinas beta/genética , gama-Globinas/genética
3.
J Comput Biol ; 25(12): 1347-1360, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30204480

RESUMO

Obesity is a major risk factor for many metabolic diseases. To understand the genetic characteristics of obese individuals, single-nucleotide polymorphisms (SNPs) derived from next-generation sequencing (NGS) provide comprehensive insight into genome-wide genetic investigation. However, interpretation of these SNP data for clinical application is difficult given the high complexity of NGS data. Hence, in this study, obesity risk prediction models based on SNPs were designed using machine learning (ML) methods, namely support vector machine (SVM), k-nearest neighbor, and decision tree (DT). This investigation obtained clinicopathological features, including 130 SNPs, sex, and age, from 139 eligible individuals. Various feature selection methods, such as stepwise multivariate linear regression (MLR), DT, and genetic algorithms, were applied to select informative features for generating obesity prediction models. Multivariate logistic regression was used to evaluate the importance of the selected features. The models trained from various features evaluated their predictive performances based on fivefold cross-validation. Three measures, namely accuracy, sensitivity, and specificity, were used to examine and compare the predictive power among various models. To design obesity prediction models using ML methods, nine SNPs, including rs10501087, rs17700144, rs2287019, rs534870, rs660339, rs7081678, rs718314, rs9816226, and rs984222, were selected based on stepwise MLR. In evaluation of model performance, the SVM model significantly outperformed other classifiers based on the same training features. The SVM model exhibits 70.77% accuracy, 80.09% sensitivity, and 63.02% specificity. This investigation has demonstrated that the selected SNPs were effective in the detection of obesity risk. Additionally, the ML-based method provides a feasible mean for conducting preliminary analyses of genetic characteristics of obesity.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Obesidade/genética , Polimorfismo de Nucleotídeo Único , Adulto , Algoritmos , Árvores de Decisões , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise de Sequência de DNA , Máquina de Vetores de Suporte
4.
Oncotarget ; 9(27): 19379-19395, 2018 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-29721210

RESUMO

Leiomyosarcomas are rare mesenchymal neoplasms characterized by a smooth muscle differentiation pattern. Due to the extremely poor prognosis in patients, the development of novel chemotherapeutic regimens remains critically important. In this study, multiple leiomyosarcoma cell lines, SK-UT1, SK-LMS1, and MES-SA were treated with varying doses of the DNA Methyltransferase Inhibitors (DNMTi) 5-azacitidine (Aza), 5-aza-2-deoxycytidine (DAC), and guadecitabine (SGI-110). The effect of these epigenetic modulators was measured using both in-vitro and in-vivo models. Of the three epigenetic modulators, Guadecitabine was the most effective at decreasing cell survival in LMS cell lines. SK-UT1 was found to be the more sensitive to all three epigenetic modulators, while SK-LMS1 and MES-SA were more resistant. The contrast in sensitivity seen was also represented by the increase in apoptosis in Aza and guadecitabine. In parallel with Aza, guadecitabine was observed to also arrest the cell cycle. Treatment with guadecitabine led to a decrease in growth across the spectrum of sensitivity in LMS cell lines, both in a delayed in vitro and in vivo model; in parallel experiments, apoptotic pathways were activated in sensitive and less sensitive lines. Additional studies are required to explore potential therapeutic applications and mechanisms for leiomyosarcoma treatment.

5.
Clin Chim Acta ; 483: 89-93, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29684380

RESUMO

BACKGROUND: The effectiveness of platelet-rich plasma (PRP) for treating soft tissue injuries is still controversial. Most of PRPs were prepared simply by concentrating in volume and were injected right after preparation in physician offices. Neither platelet count nor growth factors were quantitated in advance. We prepared and stored leukocyte and platelet-rich plasma (L-PRP) by regular separation protocols for blood components in the blood bank. And we investigated the dynamic change of growth factors in the L-PRPs over the period of storage. METHODS: The L-PRPs were prepared by 2-step centrifugation and stored agitatedly at 22 °C for 7 days in the platelet incubator of blood bank. Levels of vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF)-basic, hepatocyte growth factor (HGF), insulin-like growth factor (IGF)-1, platelet derived growth factor (PDGF)-AB, endothelial growth factor (EGF), and transforming growth factor (TGF) over the period of storage were evaluated daily after freeze-thawing to release growth factors from platelet. RESULTS: Compared to original whole blood, platelet concentration, VEGF, FGF-basic, PDGF-AB, EGF, and TGF-beta1 levels of L-PRPs significantly increased after PRP preparation. Both HGF and IGF-1 in L-PRPs remained the original plasma level. Platelet, FGF, and TGF-beta1 concentrations sustained during storage, and concentrations of VEGF, HGF, IGF-1, PDGF-AB, and EGF in L-PRPs increased over the period of storage. CONCLUSIONS: During the storage in blood bank, platelet counts and 7 growth factors sustained or reached higher level than L-PRP obtained on first day. Multiple injections of stored PRPs could become applicable by our protocol.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/análise , Plasma Rico em Plaquetas/metabolismo , Manejo de Espécimes , Adulto , Bancos de Sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Temperatura Ambiente , Fatores de Tempo
6.
Cancer Lett ; 425: 21-30, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29425687

RESUMO

The androgen-deprivation therapy (ADT) to either reduce the androgen biosynthesis (for example, Abiraterone) or to prevent binding of androgen to the androgen receptor (AR), for example using Casodex or Enzalutamide, which may result in .decrease of the prostate cancer (PCa) cell growth, yet may also increase the PCa cell invasion. In contrast, the recently identified AR degradation enhancer ASC-J9® may function via degrading the AR protein to simultaneously suppress the PCa cell proliferation and invasion. The details of this unique mechanism, however, remain unclear. Here we found that ASC-J9® could suppress PCa cell invasion via inducing the sumoylation of STAT3, thereby inhibiting the STAT3 phosphorylation that led to suppress the EMT-SNAIL2 signals in both PCa DU145 and PC3 AR-negative cells. Mutation of lysine-679 on the sumoylation site of the STAT3 effectively blocked the ASC-J9®-suppressed PCa cell invasion in both in vitro cell lines and in vivo mouse models. These results suggest that in addition to degrading AR to suppress PCa cell proliferation, ASC-J9® can also function through an AR-independent mechanism via modulating the STAT3 sumoylation to alter the phospho-STAT3 status to suppress the PCa cell invasion. These dual functions of ASC-J9® to suppress PCa proliferation and invasion (via altering STAT3 sumoylation) may help us to develop a better anti-AR compound that may overcome the current antiandrogens' unwanted side-effect of increasing the metastasis to better suppress the castration-resistant PCa progression.


Assuntos
Antineoplásicos/administração & dosagem , Curcumina/análogos & derivados , Neoplasias da Próstata/tratamento farmacológico , Fator de Transcrição STAT3/metabolismo , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Curcumina/administração & dosagem , Curcumina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Masculino , Camundongos , Invasividade Neoplásica , Fosforilação/efeitos dos fármacos , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sumoilação/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Exp Gerontol ; 106: 109-115, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29408782

RESUMO

Normal pressure hydrocephalus (NPH) was the first type of dementia ever described that can be treated using ventriculoperitoneal shunting surgery. Three typical clinical symptoms of NPH include gait disturbance, progressive cognitive dysfunction, and urinary incontinence. Although there are articles that have discovered several cerebrospinal fluid (CSF) protein biomarkers associated with NPH; however, studies examining individual and total protein concentrations from the ventricular CSF before and after shunting surgery are lacking. This study used proteomics to calculate the CSF individual and total protein concentrations before, and one week, one month and three months after the shunting surgery. Parameters of cadence, step length, walking speed, and percentages of single- and double-limb support in a gait cycle were measured. Protein concentrations associated with anti-oxidation, aging, and in the prevention of neurotoxic agent production increased by at least 2-folds after the surgery, indicating that the brain may become less susceptible to neurodegeneration. These proteins were alpha-1B-glycoprotein, apolipoproteins A-1 & A-IV, prostaglandin-H2 D-isomerase, alpha-1-antitrypsin, and serotransferrin. In gait analysis, lower cadence, decreased double-limb support, longer step length, and increased single-limb support were observed after the surgery, indicating a more stable walking balance. These changes lasted for a period of at least 3 months. As a result, shunting surgery may be recommended for geriatric patients with confirmed diagnosis of normal pressure hydrocephalus.


Assuntos
Proteínas do Líquido Cefalorraquidiano/líquido cefalorraquidiano , Hidrocefalia de Pressão Normal/líquido cefalorraquidiano , Hidrocefalia de Pressão Normal/fisiopatologia , Hidrocefalia de Pressão Normal/cirurgia , Idoso , Biomarcadores/líquido cefalorraquidiano , Cognição , Eletroforese em Gel Bidimensional , Feminino , Análise da Marcha , Humanos , Masculino , Proteômica , Análise de Regressão , Taiwan , Derivação Ventriculoperitoneal
8.
Cell Death Differ ; 24(9): 1502-1517, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28644440

RESUMO

While the androgen receptor (AR) might promote renal cell carcinoma (RCC) initiation and progression, the molecular mechanisms involved remain largely unclear. Here, we discovered the novel LncRNA-SARCC, which was suppressed and associated with better prognosis in RCC. Preclinical studies using multiple RCC cells and in vivo mouse model indicated that LncRNA-SARCC could attenuate RCC cell invasion, migration and proliferation in vitro and in vivo. Mechanistically, LncRNA-SARCC bound and destabilized AR protein with an inhibition of AR function, which led to transcriptionally de-repress miR-143-3p expression, thus inhibition of its downstream signals including AKT, MMP-13, K-RAS and P-ERK. In addition, bisulfite sequencing analysis substantiated that LncRNA-SARCC promoter was highly methylated in renal cancer tissues compared with paired non-cancerous renal tissues. Notably, treating with Sunitinib, the multi-targeted receptor tyrosine kinase inhibitor, increased the expression of LncRNA-SARCC, which decreased RCC cells resistance to Sunitinib. Thus, our study presented a road map for targeting this newly identified LncRNA-SARCC and its pathway, which expands potential therapeutic strategies for RCC treatment.


Assuntos
Carcinoma de Células Renais/genética , Neoplasias Renais/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/fisiologia , Animais , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Proliferação de Células/fisiologia , Imunoprecipitação da Cromatina , Progressão da Doença , Regulação Neoplásica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Neoplasias Renais/patologia , Masculino , Camundongos , Camundongos Nus , MicroRNAs/genética , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Am J Community Psychol ; 59(1-2): 120-132, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28349606

RESUMO

The Transconceptual Model of Empowerment and Resilience (American Journal of Community Psychology, 52, 2013, 333) suggests that a set of resilience and empowerment resources fuel both initial and sustained participation in collective action. Using the case study of a prodemocracy movement in Hong Kong, the present study focused on the subset of those resources that are relevant in ongoing collective action: efficacy, skills, and maintenance. As individuals possess varying combinations of these resources, the present study utilized latent profile analysis to test how patterns of empowerment and resilience resources influence initial and long-term collective action. Five groups were identified: (a) Uncommitted/Uninspired; (b) Committed to Status Quo; (c) Mainstream Populist; (d) Empowered; and (e) Ambivalent. ANOVA and ANCOVA analyses found that there are significant group differences in initial and long-term participation. Groups with higher level of resources reported greater levels of initial participation than their counterparts; however, high resource groups did not uniformly report greater levels of intention to participate in future collective action. Of the maintenance processes tested, collective identity emerged as a particularly important predictor differentiating initial and sustained participation. Findings from the present study raise questions about how individuals with multiple identities can come together and participate in collective action.


Assuntos
Democracia , Política , Resiliência Psicológica , Adolescente , Feminino , Recursos em Saúde , Hong Kong , Humanos , Masculino , Autoeficácia , Adulto Jovem
10.
J Med Internet Res ; 18(3): e25, 2016 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-26976273

RESUMO

BACKGROUND: The Internet has increasingly become a popular source of health information by connecting individuals with health content, experts, and support. More and more, individuals turn to social media and Internet sites to share health information and experiences. Although online health information seeking occurs worldwide, limited empirical studies exist examining cross-cultural differences in perceptions about user-generated, experience-based information compared to expertise-based information sources. OBJECTIVE: To investigate if cultural variations exist in patterns of online health information seeking, specifically in perceptions of online health information sources. It was hypothesized that Koreans and Hongkongers, compared to Americans, would be more likely to trust and use experience-based knowledge shared in social Internet sites, such as social media and online support groups. Conversely, Americans, compared to Koreans and Hongkongers, would value expertise-based knowledge prepared and approved by doctors or professional health providers more. METHODS: Survey questionnaires were developed in English first and then translated into Korean and Chinese. The back-translation method ensured the standardization of questions. Surveys were administered using a standardized recruitment strategy and data collection methods. RESULTS: A total of 826 participants living in metropolitan areas from the United States (n=301), Korea (n=179), and Hong Kong (n=337) participated in the study. We found significant cultural differences in information processing preferences for online health information. A planned contrast test revealed that Koreans and Hongkongers showed more trust in experience-based health information sources (blogs: t451.50=11.21, P<.001; online support group: t455.71=9.30, P<.001; social networking sites [SNS]: t466.75=11.36, P<.001) and also reported using blogs (t515.31=6.67, P<.001) and SNS (t529.22=4.51, P<.001) more frequently than Americans. Americans showed a stronger preference for using expertise-based information sources (eg, WebMD and CDC) compared to Koreans and Hongkongers (t360.02=3.01, P=.003). Trust in expertise-based information sources was universal, demonstrating no cultural differences (Brown-Forsythe F2,654=1.82, P=.16). Culture also contributed significantly to differences in searching information on behalf of family members (t480.38=5.99, P<.001) as well as to the goals of information searching. CONCLUSIONS: This research found significant cultural differences in information processing preferences for online health information. Further discussion is included regarding effective communication strategies in providing quality health information.


Assuntos
Informação de Saúde ao Consumidor , Características Culturais , Comportamento de Busca de Informação , Mídias Sociais/estatística & dados numéricos , Confiança , Adulto , Comparação Transcultural , Feminino , Hong Kong , Humanos , Internet , Masculino , Médicos , República da Coreia , Inquéritos e Questionários , Estados Unidos , Adulto Jovem
11.
Oncotarget ; 6(40): 43081-9, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26517808

RESUMO

Early studies indicated that several inflammatory immune cells, including macrophages, mast cells, B and T cells in the tumor microenvironment, might influence cancer progression. Here we found that bladder cancer (BCa) cells could recruit more neutrophils than normal bladder cells. The consequences of recruiting more neutrophils might then increase BCa cell invasion via up-regulating androgen receptor (AR) signals. Mechanism dissection revealed infiltrating neutrophils could up-regulate AR signals via either increased AR mRNA/protein expression or increased AR transactivation. The increased AR signals might then enhance BCa cell invasion via increasing MMP13 expression. Together, these results might provide us a new potential therapeutic approach to better battle BCa metastasis via targeting the newly identified signaling from infiltrating neutrophils to BCa through AR to MMP13 signals.


Assuntos
Carcinoma de Células de Transição/patologia , Metaloproteinase 13 da Matriz/metabolismo , Neutrófilos/imunologia , Receptores Androgênicos/metabolismo , Transdução de Sinais , Neoplasias da Bexiga Urinária/patologia , Western Blotting , Carcinoma de Células de Transição/imunologia , Carcinoma de Células de Transição/metabolismo , Linhagem Celular Tumoral , Técnicas de Silenciamento de Genes , Humanos , Invasividade Neoplásica/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/fisiologia , Neoplasias da Bexiga Urinária/imunologia , Neoplasias da Bexiga Urinária/metabolismo
12.
Health Mark Q ; 31(3): 213-30, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25120043

RESUMO

Worrying incidents exist where disgruntled nurses destroy good service quality through sabotage behavior. Previous studies report the organizational and environmental factors that might lead to service sabotage behaviors; here individual differences in proclivity to service sabotage within any given environment of managerial context are reported. The study first uses interviews to establish typologies of difficult patients. Regression analysis and ANOVA applied to survey data shows that low self-esteem in nurses leads to service sabotage behavior, and that these nurses are less mature both chronologically and emotionally, less experienced, and less educated than their more typical counterparts.


Assuntos
Relações Enfermeiro-Paciente , Recursos Humanos de Enfermagem no Hospital/psicologia , Autoimagem , Adulto , Atitude do Pessoal de Saúde , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Inquéritos e Questionários , Local de Trabalho/psicologia , Adulto Jovem
13.
Biomed Res Int ; 2014: 762570, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24839606

RESUMO

Compressive stimulation can modulate articular chondrocyte functions. Nevertheless, the relevant studies are not comprehensive. This is primarily due to the lack of cell culture apparatuses capable of conducting the experiments in a high throughput, precise, and cost-effective manner. To address the issue, we demonstrated the use of a perfusion microcell culture system to investigate the stimulating frequency (0.5, 1.0, and 2.0 Hz) effect of compressive loading (20% and 40% strain) on the functions of articular chondrocytes. The system mainly integrates the functions of continuous culture medium perfusion and the generation of pneumatically-driven compressive stimulation in a high-throughput micro cell culture system. Results showed that the compressive stimulations explored did not have a significant impact on chondrocyte viability and proliferation. However, the metabolic activity of chondrocytes was significantly affected by the stimulating frequency at the higher compressive strain of 40% (2 Hz, 40% strain). Under the two compressive strains studied, the glycosaminoglycans (GAGs) synthesis was upregulated when the stimulating frequency was set at 1 Hz and 2 Hz. However, the stimulating frequencies explored had no influence on the collagen production. The results of this study provide useful fundamental insights that will be helpful for cartilage tissue engineering and cartilage rehabilitation.


Assuntos
Cartilagem Articular/crescimento & desenvolvimento , Técnicas de Cultura de Células , Condrócitos/metabolismo , Engenharia Tecidual , Reatores Biológicos , Cartilagem Articular/citologia , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Condrócitos/citologia , Colágeno/metabolismo , Glicosaminoglicanos/metabolismo , Humanos
14.
Stroke ; 44(1): 162-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23192759

RESUMO

BACKGROUND AND PURPOSE: The neurovascular unit is a major target of hypoxia-ischemia (HI) injury in the neonatal brain. Although neurons are the cellular target of ischemic preconditioning (IP), vessel tolerance also contributes greatly to protection. Nerves and vessels cross-talk and use common signals during development. Cellular inhibitor of apoptosis 1 (cIAP1) is an important regulator that inhibits apoptosis. This study hypothesized that cIAP1 is a shared molecule underlying IP-mediated neurovascular protection against HI in the neonatal brain. METHODS: In vivo IP was induced by 2-hour reversible occlusion of right carotid artery 24 hours before HI on postpartum day 7 in rat pups. In vitro oxygen-glucose deprivation (OGD) preconditioning was established in SH-SY5Y neuronal cells and in human microvascular endothelial cell-1 vascular endothelial cells. cIAP1 expression was inhibited by cIAP1 small interfering RNA in vivo or by lentivirus-mediated short hairpin RNA in vitro, or was upregulated by the lentiviral expression system. RESULTS: IP reduced apoptosis, selectively increased cIAP1 in neurons and vascular endothelial cells, and provided long-term neuroprotection against HI. Intracerebroventricular delivery of cIAP1 small interfering RNA significantly attenuated IP-mediated cIAP1 upregulation and neuroprotection in vivo. In vitro, OGD preconditioning induced cIAP1 and protected against OGD cell death in SH-SY5Y neuronal and human microvascular endothelial cells-1. Knockdown of cIAP1 by lentivirus-mediated short hairpin RNA decreased the protective effect of OGD preconditioning in SH-SY5Y and human microvascular endothelial cell-1, whereas overexpression of cIAP1 by lentivirus protected against OGD in these cells. CONCLUSIONS: cIAP1 is a shared molecule underlying IP-induced protection in neurons and vascular endothelial cells against HI in the neonatal brain.


Assuntos
Encéfalo/metabolismo , Endotélio Vascular/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Proteínas Inibidoras de Apoptose/biossíntese , Precondicionamento Isquêmico/métodos , Neurônios/metabolismo , Animais , Animais Recém-Nascidos , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Linhagem Celular Tumoral , Endotélio Vascular/patologia , Humanos , Hipóxia-Isquemia Encefálica/patologia , Hipóxia-Isquemia Encefálica/prevenção & controle , Masculino , Neurônios/patologia , Ratos , Ratos Sprague-Dawley
15.
J Biol Chem ; 287(38): 32216-21, 2012 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-22833682

RESUMO

Retinoic acid-inducible gene I (RIG-I)-like receptors (RLRs) are key RNA viral sensors for triggering antiviral immunity. The underlying mechanisms for RLRs to trigger antiviral immunity have yet to be explored. Here we report the identification of TAPE (TBK1-associated protein in endolysosomes) as a novel regulator of the RLR pathways. TAPE functionally and physically interacts with RIG-I, MDA5, and IPS-1 to activate the IFN-ß promoter. TAPE knockdown impairs IFN-ß activation induced by RLRs but not IPS-1. TAPE-deficient cells are defective in cytokine production upon RLR ligand stimulation. During RNA virus infection, TAPE knockdown or deficiency diminishes cytokine production and antiviral responses. Our data demonstrate a critical role for TAPE in linking RLRs to antiviral immunity.


Assuntos
RNA Helicases DEAD-box/metabolismo , Proteínas de Ligação a DNA/química , Proteínas Repressoras/química , Animais , Antivirais/química , Antivirais/farmacologia , Linhagem Celular Tumoral , Proteína DEAD-box 58 , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Células HEK293 , Humanos , Sistema Imunitário , Macrófagos/metabolismo , Camundongos , Camundongos Knockout , Ligação Proteica , Proteínas Serina-Treonina Quinases/química , Interferência de RNA , Proteínas Repressoras/metabolismo , Transdução de Sinais , Células Vero
16.
J Biol Chem ; 286(9): 7043-51, 2011 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-21189260

RESUMO

The innate immune system elicits the first wave of immune responses against pathogen infection. Its operational modes are complex and have yet to be defined. Here, we report the identification of an innate immune regulator termed TAPE (TBK1-associated protein in endolysosomes), previously known as CC2D1A/Freud-1/Aki-1, which modulates the TLR3 and TLR4 pathways. We found that TAPE activated the TBK1, NF-κB, and ERK pathways leading to IFN-ß and inflammatory cytokine induction. TAPE was shown to colocalize with endosomal marker Rab5 and lysosomal marker LAMP1 in mammalian cells, suggesting that TAPE resided in endolysosomes. Knockdown of TAPE selectively impaired the TLR3 and endocytic TLR4 pathways to IFN-ß induction. Furthermore, TAPE interacted and synergized with Trif to activate IFN-ß. TAPE knockdown failed to block Trif-mediated IFN-ß induction, whereas Trif knockdown impaired the TLR3 and TAPE cooperation on IFN-ß induction, suggesting that TAPE acts upstream of Trif. Together, our data demonstrate a central role for TAPE in linking TLR3 and TLR4 to innate immune defenses at an early step.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Fatores Imunológicos/metabolismo , Transdução de Sinais/imunologia , Receptor 3 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Proteínas de Ligação a DNA/imunologia , Endossomos/imunologia , Endossomos/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/imunologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células HEK293 , Humanos , Fatores Imunológicos/imunologia , Interferon beta/imunologia , Interferon beta/metabolismo , Lisossomos/imunologia , Lisossomos/metabolismo , Proteínas Serina-Treonina Quinases/imunologia , Proteínas Serina-Treonina Quinases/metabolismo , Receptor 3 Toll-Like/imunologia , Receptor 4 Toll-Like/imunologia
17.
Gen Comp Endocrinol ; 172(1): 140-50, 2011 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-21185293

RESUMO

Growth hormone (GH) is synthesized and present in the developing chick retina, where it may have local actions in retinal cell differentiation similar to those of conventional growth factors. We have previously shown that retinal GH has neuroprotective effects in retinal ganglion cells. In this paper, we extend our earlier functional studies by examining the in vivo effects of a GH siRNA (NR-cGH-1) after microinjection into the eye cup of the developing chick embryo in ovo. We show that intra-vitreous cGH siRNA lowers both GH mRNA and insulin-like growth factor-1 (IGF-1) mRNA levels in the retina in vivo, and concomitantly elevates the numbers of apoptotic cells in the retina. These effects are apparent 6h after treatment, and persist for at least 24h. The apoptotic cells induced by GH withdrawal were primarily located close to the optic fissure of the developing eye, and were distributed in clusters, suggesting that there are sub-populations of retinal cells that are particularly susceptible to apoptotic stimuli. These results support our view that a GH/IGF-1 axis in retinal cells regulates retinal cell survival in vivo.


Assuntos
Hormônio do Crescimento/farmacologia , Retina/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Células Cultivadas , Embrião de Galinha , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Hormônio do Crescimento/antagonistas & inibidores , Hormônio do Crescimento/genética , Hormônio do Crescimento/metabolismo , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Injeções Intravítreas , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Codorniz/genética , Codorniz/metabolismo , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/farmacologia , Retina/citologia , Retina/metabolismo , Retina/fisiologia , Transfecção
18.
Int J Cardiol ; 146(1): 44-50, 2011 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-19560219

RESUMO

BACKGROUND: The reported presence of DNA breaks, based on a positive reaction to the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP in situ nick end-labelling (TUNEL) assay, in fibrillating human right atria of cardiac valve disease may suggest apoptotic myocyte death. However, TUNEL positivity may reflect conditions other than cell death. METHODS: This study comprised 27 adult patients (14 patients with persistent atrial fibrillation and 13 in sinus rhythm) with significant mitral and tricuspid valve diseases. Atrial tissues were obtained during surgery. RESULTS: Immunohistochemical study demonstrated that 31.1±12.2% of the myocytes had TUNEL-positive nuclei in the fibrillating right atria whereas 37.4±23.2% of the myocytes had TUNEL-positive nuclei in the right atrial myocardium in sinus rhythm (p=0.505). However, most nuclei of TUNEL-positive myocytes in the right atria also expressed proliferating cell nuclear antigen (PCNA), an indicator of DNA replication and repair but never Ki-67, a replication-associated antigen (TUNEL(+)/PCNA(+) vs. TUNEL(+)/PCNA(-), 30.5±10.8% vs. 1.2±1.5%, p=0.005, in the atrial fibrillation group and 32.8±18.6% vs. 4.6±8.1%, p=0.003, in the sinus group), suggesting that most TUNEL-positive myocytes were undergoing DNA repair. In addition, the incidence of TUNEL-positive myocytes significantly and positively correlated with the incidence of PCNA-positive myocytes (r=0.5, p<0.03 in the right atria; r=0.661, p<0.04 in the left atria). CONCLUSIONS: Cell death by apoptosis occurs in a small percentage of atrial cardiomyocytes in mitral and tricuspid valve diseases and DNA repair is more important and preserves the cardiomyocytes.


Assuntos
Reparo do DNA/genética , Doenças das Valvas Cardíacas/patologia , Marcação In Situ das Extremidades Cortadas , Valva Mitral/patologia , Miócitos Cardíacos/patologia , Valva Tricúspide/patologia , Adolescente , Adulto , Idoso , Sobrevivência Celular/genética , Feminino , Átrios do Coração/patologia , Átrios do Coração/fisiopatologia , Doenças das Valvas Cardíacas/genética , Humanos , Marcação In Situ das Extremidades Cortadas/métodos , Masculino , Pessoa de Meia-Idade , Valva Mitral/fisiopatologia , Miócitos Cardíacos/química , Valva Tricúspide/fisiopatologia , Adulto Jovem
19.
Anal Chim Acta ; 669(1-2): 68-74, 2010 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-20510905

RESUMO

A urea biosensor based on pH-sensitive Sm(2)TiO(5) electrolyte-insulator-semiconductor (EIS) has been described. We used X-ray diffraction, Auger electron spectroscopy, and atomic force microscopy to investigate the structural and morphological features of high-k Sm(2)TiO(5) sensing membranes that had been subjected to annealing at different temperatures. The EIS device incorporating a high-k Sm(2)TiO(5) sensing film that had been annealed at 900 degrees C exhibited good sensing characteristics, including a high sensitivity of 60.5 mV/pH (in solutions from pH 2 to 12), a small hysteresis voltage of 2.72 mV (in the pH loop 7-->4-->7-->10-->7), and a low drift rate of 1.15 mV h(-1) (in the buffer solution at pH 7). The Sm(2)TiO(5) EIS device also showed a high selective response towards H(+). This improvement can be attributed to the small number of crystal defects and the large surface roughness. In addition, the urea biosensor based on pH-sensitive EIS incorporating a Sm(2)TiO(5) sensing membrane annealed at 900 degrees C allowed the potentiometric analysis of urea, at concentrations ranging from 0.1 to 32 mM, with a sensitivity of 72.85 mV/purea.


Assuntos
Técnicas Biossensoriais , Ureia , Técnicas Biossensoriais/métodos , Eletrólitos/química , Temperatura Alta , Concentração de Íons de Hidrogênio , Potenciometria , Samário/química , Semicondutores/instrumentação , Titânio/química , Ureia/análise
20.
Gen Comp Endocrinol ; 165(1): 111-9, 2010 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19539627

RESUMO

We have previously shown that growth hormone (GH) is produced within cells of the chick embryo retina where it appears to act as an autocrine/paracrine anti-apoptotic factor in the regulation of programmed cell death during retinal development. These investigations were carried out on cultured chick embryo retinal ganglion cells (RGCs) as well as on the chick embryo retina in ovo, using GH protein knock-down by immunoneutralization. We have now investigated the putative neuroprotective actions of GH using a quail embryo neural retina cell line (QNR/D) treated with GH siRNA to silence the local synthesis of GH. We now show that knock-down of GH by gene silencing in cells of this cultured embryonic neural retina cell line, using NR-cGH-1 siRNA, correlates with the increased appearance in the cultures of cells with apoptotic nuclear morphology. This result is consistent with our previous results using protein knock-down by immunoneutralization. We thus validate, using different technology and a different culture system, our contention that GH, produced locally by cells of the neural retina acts in an autocrine or paracrine manner to regulate cell survival in the retina.


Assuntos
Regulação da Expressão Gênica , Hormônio do Crescimento/metabolismo , Retina/citologia , Retina/metabolismo , Células Ganglionares da Retina/metabolismo , Animais , Apoptose/genética , Apoptose/fisiologia , Western Blotting , Linhagem Celular , Embrião de Galinha , Galinhas , Ensaio de Imunoadsorção Enzimática , Hormônio do Crescimento/genética , Hipófise/metabolismo , RNA Interferente Pequeno , Retina/embriologia , Células Ganglionares da Retina/citologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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