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1.
J Youth Adolesc ; 53(5): 1155-1170, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38102531

RESUMO

During emerging adulthood, individuals' subjective well-being declines owing to challenges regarding identity, work, and romantic relationships. Although the relationships among personality traits, self-construal, and well-being have been examined, studies have focused on personal rather than relational subjective well-being. Furthermore, self-construal's moderating effect on the relationship between personality traits and subjective well-being remains unclear. Therefore, this study examined the relationships among the Big-five personality traits and subjective well-being (life satisfaction, happiness, and interdependent happiness) and the moderating effect of self-construal among 1548 Japanese emerging adults (Mage = 22.24, SD = 1.01). Regression analysis indicated that all aspects of subjective well-being were negatively associated with neuroticism and positively associated with extraversion, independent and interdependent self-construal. Further, agreeableness was positively associated with personal and relational well-being. Independent or interdependent self-construal can moderate the relationships between neuroticism, extraversion, and agreeableness and subjective well-being. Overall, these findings provide valuable insights for improving Japanese emerging adults' well-being.


Assuntos
Felicidade , Personalidade , Adulto , Humanos , Adulto Jovem , Neuroticismo , Análise de Regressão
2.
Front Psychol ; 14: 1328593, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38282840

RESUMO

Introduction: This study aimed to develop a Japanese version of the motivation to lead (MTL) scale consisting of three factors-affective-identity MTL, non-calculative MTL, and social-normative MTL-and examine its construct validity and reliability. Methods: The participants comprised 500 university students and 500 employees aged 20-29 years registered with a Japanese research company. Results: Based on a confirmatory factor analysis, the three-factor model was found to be appropriate for the Japanese context. The measurement invariance analyses indicated scalar invariance between students and employees and between men and women. Finally, the correlation analysis with the Big Five personality traits conducted to examine construct validity indicated that affective-identity MTL and social-normative MTL had significant relationships with all five traits (extraversion, agreeableness, conscientiousness, open-mindedness, and negative emotionality). Although non-calculative MTL was not significantly correlated, it can be interpreted in the Japanese context. Discussion: The results indicate the adequate construct validity and reliability of the Japanese version of the MTL scale. These findings hold significant implications for leadership development and selection in Japan, highlighting the motivational factors that drive effective leadership.

3.
J Endod ; 48(5): 632-640, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35181456

RESUMO

INTRODUCTION: Antiresorptive drugs are widely used to treat osteoporosis and other systemic bone diseases, although their efficacy for local bone resorption after localized inflammation has not been fully elucidated. We examined the effects of an anti-receptor activator of nuclear factor kappa B ligand (RANKL) antibody and the bisphosphonate zoledronic acid (ZOL) on periapical lesion (PL) development in mice. METHODS: Dental pulp of lower first molars in mice was removed, with the exposed dental pulp chambers left open to the oral environment to induce apical periodontitis. An anti-RANKL antibody or ZOL was intraperitoneally injected once per week until postoperative day 21, and then micro-computed tomographic imaging and histologic analyses were performed. RESULTS: PL enlargement was inhibited by both the anti-RANKL antibody and ZOL in a dose-dependent manner, and a reduction of inflammatory cell infiltration in apical tissues inhibited periapical bone resorption. The anti-RANKL antibody decreased the number of osteoclasts in periapical tissues, whereas ZOL suppressed periapical bone resorption with osteoclast numbers maintained. Although the administration of each of the antiresorptive drugs increased femoral bone mass, femoral bone mineral density in the PL group was lower compared with the sham-operated group. CONCLUSIONS: These results suggest that an antiresorptive drug administered systemically is distributed to areas of local inflammation in the jaw can prevent PL development.


Assuntos
Conservadores da Densidade Óssea , Reabsorção Óssea , Animais , Conservadores da Densidade Óssea/farmacologia , Conservadores da Densidade Óssea/uso terapêutico , Reabsorção Óssea/tratamento farmacológico , Reabsorção Óssea/patologia , Reabsorção Óssea/prevenção & controle , Inflamação/patologia , Camundongos , NF-kappa B , Osteoclastos , Ligante RANK , Ácido Zoledrônico/farmacologia
4.
Biomed Pharmacother ; 146: 112593, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34968925

RESUMO

Neural crest-derived cells (NCDCs), which exist as neural crest cells during the fetal stage and differentiate into palate cells, also exist in adult palate tissues, though with unknown roles. In the present study, NCDCs were labeled with EGFP derived from P0-Cre/CAG-CAT-EGFP (P0-EGFP) double transgenic mice, then their function in palate mucosa wound healing was analyzed. As a palate wound healing model, left-side palate mucosa of P0-EGFP mice was resected, and stem cell markers and keratinocyte markers were detected in healed areas. NCDCs were extracted from normal palate mucosa and precultured with stem cell media for 14 days, then were differentiated into keratinocytes or osteoblasts to analyze pluripotency. The wound healing process started with marginal mucosal regeneration on day two and the entire wound area was lined by regenerated mucosa with EGFP-positive cells (NCDCs) on day 28. EGFP-positive cells comprised approximately 60% of cells in healed oral mucosa, and 65% of those expressed stem cell markers (Sca-1+, PDGFRα+) and 30% expressed a keratinocyte marker (CK13+). In tests of cultured palate mucosa cells, approximately 70% of EGFP-positive cells expressed stem cell markers (Sca-1+, PDGFRα+). Furthermore, under differentiation inducing conditions, cultured EGFP-positive cells were successfully induced to differentiate into keratinocytes and osteoblasts. We concluded that NCDCs exist in adult palate tissues as stem cells and have potential to differentiate into various cell types during the wound healing process.


Assuntos
Diferenciação Celular/fisiologia , Queratinócitos/citologia , Osteoblastos/citologia , Palato/citologia , Cicatrização/fisiologia , Animais , Camundongos , Camundongos Transgênicos , Mucosa Bucal/metabolismo , Crista Neural/citologia
5.
Front Psychol ; 13: 1053601, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36743639

RESUMO

This study developed a Japanese version of the Revised Version of the Compound Psychological Capital Scale (CPC-12R) and tested its reliability and construct validity. The participants were 1,000 young adults (500 university students and 500 employees) recruited through an internet survey. Confirmatory factor analysis showed that the four first-order factors (hope, optimism, resilience, and self-efficacy) and one second-order factor (PsyCap) model of the previous study is appropriate for the Japanese context. In addition, Cronbach's α and omega-higher-order of CPC-12R were sufficient. The measurement invariance analysis suggested sufficient scalar invariances for the employees and university students and across genders. The Japanese version of the CPC-12R had moderate positive correlations with job satisfaction, work engagement, conscientiousness, and extraversion, as well as a moderate negative correlation with negative emotionality. These findings provide evidence for sufficient reliability and construct validity of the Japanese version of the CPC-12R.

6.
Nat Commun ; 11(1): 3369, 2020 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-32632153

RESUMO

Induced pluripotent stem cell (iPSC)-derived dopaminergic (DA) neurons are an expected source for cell-based therapies for Parkinson's disease (PD). The regulatory criteria for the clinical application of these therapies, however, have not been established. Here we show the results of our pre-clinical study, in which we evaluate the safety and efficacy of dopaminergic progenitors (DAPs) derived from a clinical-grade human iPSC line. We confirm the characteristics of DAPs by in vitro analyses. We also verify that the DAP population include no residual undifferentiated iPSCs or early neural stem cells and have no genetic aberration in cancer-related genes. Furthermore, in vivo studies using immunodeficient mice reveal no tumorigenicity or toxicity of the cells. When the DAPs are transplanted into the striatum of 6-OHDA-lesioned rats, the animals show behavioral improvement. Based on these results, we started a clinical trial to treat PD patients in 2018.


Assuntos
Neurônios Dopaminérgicos/citologia , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Neurais/transplante , Doença de Parkinson/terapia , Transplante de Células-Tronco/métodos , Animais , Diferenciação Celular/genética , Linhagem Celular , Modelos Animais de Doenças , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Macaca fascicularis , Masculino , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Avaliação de Resultados em Cuidados de Saúde/métodos , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Ratos Nus , Transplante Heterólogo
7.
Neural Regen Res ; 15(3): 557-568, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31571668

RESUMO

The consequences of neonatal white matter injury are devastating and represent a major societal problem as currently there is no cure. Prematurity, low weight birth and maternal pre-natal infection are the most frequent causes of acquired myelin deficiency in the human neonate leading to cerebral palsy and cognitive impairment. In the developing brain, oligodendrocyte (OL) maturation occurs perinatally, and immature OLs are particularly vulnerable. Cell replacement therapy is often considered a viable option to replace progenitors that die due to glutamate excitotoxicity. We previously reported directed specification and mobilization of endogenous committed and uncommitted neural progenitors by the combination of transferrin and insulin growth factor 1 (TSC1). Here, considering cell replacement and integration as therapeutic goals, we examined if OL progenitors (OLPs) grafted into the brain parenchyma of mice that were subjected to an excitotoxic insult could rescue white matter injury. For that purpose, we used a well-established model of glutamate excitotoxic injury. Four-day-old mice received a single intraparenchymal injection of the glutamate receptor agonist N-methyl-D-aspartate alone or in conjunction with TSC1 in the presence or absence of OLPs grafted into the brain parenchyma. Energetics and expression of stress proteins and OL developmental specific markers were examined. A comparison of the proteomic profile per treatment was also ascertained. We found that OLPs did not survive in the excitotoxic environment when grafted alone. In contrast, when combined with TSC1, survival and integration of grafted OLPs was observed. Further, energy metabolism in OLPs was significantly increased by N-methyl-D-aspartate and modulated by TSC1. The proteomic profile after the various treatments showed elevated ubiquitination and stress/heat shock protein 90 in response to N-methyl-D-aspartate. These changes were reversed in the presence of TSC1 and ubiquitination was decreased. The results obtained in this pre-clinical study indicate that the use of a combinatorial intervention including both trophic support and healthy OLPs constitutes a promising approach for long-term survival and successful graft integration. We established optimal conditioning of the host brain environment to promote long-term survival and integration of grafted OLPs into an inflamed neonate host brain. Experimental procedures were performed under the United States Public Health Service Guide for the Care and Use of Laboratory Animals and were approved by the Institutional Animal Care Committee at (UCLA) (ARC #1992-034-61) on July 1, 2010.

8.
Clin Cancer Res ; 23(17): 5101-5111, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28539465

RESUMO

Purpose: Genomic alterations in blood-derived circulating tumor DNA (ctDNA) from patients with non-small cell lung adenocarcinoma (NSCLC) were ascertained and correlated with clinical characteristics and therapeutic outcomes.Experimental Design: Comprehensive plasma ctDNA testing was performed in 88 consecutive patients; 34 also had tissue next-generation sequencing; 29, other forms of genotyping; and 25 (28.4%) had no tissue molecular tests because of inadequate tissue or biopsy contraindications.Results: Seventy-two patients (82%) had ≥1 ctDNA alteration(s); among these, 75% carried alteration(s) potentially actionable by FDA-approved (61.1%) or experimental drug(s) in clinical trials (additional 13.9%). The most frequent alterations were in the TP53 (44.3% of patients), EGFR (27.3%), MET (14.8%), KRAS (13.6%), and ALK (6.8%) genes. The concordance rate for EGFR alterations was 80.8% (100% vs. 61.5%; ≤1 vs. >1 month between ctDNA and tissue tests; P = 0.04) for patients with any detectable ctDNA alterations. Twenty-five patients (28.4%) received therapy matching ≥1 ctDNA alteration(s); 72.3% (N = 16/22) of the evaluable matched patients achieved stable disease ≥6 months (SD) or partial response (PR). Five patients with ctDNA-detected EGFR T790M were subsequently treated with a third generation EGFR inhibitor; all five achieved SD ≥ 6 months/PR. Patients with ≥1 alteration with ≥5% variant allele fraction (vs. < 5%) had a significantly shorter median survival (P = 0.012).Conclusions: ctDNA analysis detected alterations in the majority of patients, with potentially targetable aberrations found at expected frequencies. Therapy matched to ctDNA alterations demonstrated appreciable therapeutic efficacy, suggesting clinical utility that warrants future prospective studies. Clin Cancer Res; 23(17); 5101-11. ©2017 AACR.


Assuntos
Adenocarcinoma/sangue , Adenocarcinoma/tratamento farmacológico , Biomarcadores Tumorais/sangue , DNA Tumoral Circulante/sangue , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Adulto , Idoso , Idoso de 80 Anos ou mais , Ensaios Clínicos como Assunto , Feminino , Genoma Humano/genética , Genômica , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Estadiamento de Neoplasias
9.
Eur J Neurosci ; 45(5): 733-747, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28083884

RESUMO

The Reelin-signaling pathway is essential for correct neuronal positioning within the central nervous system. Mutant mice with a deletion of Reelin, its lipoprotein receptors, or its intracellular adaptor protein Disabled-1 (Dab1), exhibit nociceptive abnormalities: thermal (heat) hyperalgesia and reduced mechanical sensitivity. To determine dorsal horn alterations associated with these nociceptive abnormalities, we first characterized the correctly positioned Dab1 neurons in wild-type and mispositioned neurons in Reelin-signaling pathway mutant lumbar spinal cord. Using immunofluorescence, we found that 70% of the numerous Dab1 neurons in Reln+/+ laminae I-II and 67% of those in the lateral reticulated area and lateral spinal nucleus (LSN) co-express the LIM-homeobox transcription factor 1 beta (Lmx1b), an excitatory glutamatergic neuron marker. Evidence of Dab1- and Dab1-Lmx1b neuronal positioning errors was found within the isolectin B4 terminal region of Reln-/- lamina IIinner and in the lateral reticulated area and LSN, where about 50% of the Dab1-Lmx1b neurons are missing. Importantly, Dab1-Lmx1b neurons in laminae I-II and the lateral reticulated area express Fos after noxious thermal or mechanical stimulation and thus participate in these circuits. In another pain relevant locus - the lateral cervical nucleus (LCN), we also found about a 50% loss of Dab1-Lmx1b neurons in Reln-/- mice. We suggest that extensively mispositioned Dab1 projection neurons in the lateral reticulated area, LSN, and LCN and the more subtle positioning errors of Dab1 interneurons in laminae I-II contribute to the abnormalities in pain responses found in Reelin-signaling pathway mutants.


Assuntos
Proteínas com Homeodomínio LIM/genética , Proteínas do Tecido Nervoso/genética , Nociceptividade , Células do Corno Posterior/metabolismo , Fatores de Transcrição/genética , Animais , Moléculas de Adesão Celular Neuronais/genética , Moléculas de Adesão Celular Neuronais/metabolismo , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Proteínas com Homeodomínio LIM/metabolismo , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Células do Corno Posterior/fisiologia , Proteína Reelina , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Fatores de Transcrição/metabolismo
10.
Mol Cell Biol ; 37(5)2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-27956699

RESUMO

One major concern over the clinical application of embryonic stem cell (ESC)-derived cells is the potentiation of latent tumorigenicity by residual undifferentiated cells. Despite the use of intensive methodological approaches to eliminate residual undifferentiated cells, the properties of these cells remain elusive. Here, we show that under a serum-free neural differentiation condition, residual undifferentiated cells markedly delay progression of their cell cycle without compromising their pluripotency. This dormant pluripotency was maintained during reculture of the cells under a serum-free condition, whereas upon serum stimulation, the cells exited the dormant state and restarted proliferation and differentiation into all three germ layers. Microarray analysis revealed a set of genes that is significantly upregulated in the dormant ESCs compared with their levels of regulation in proliferating ESCs. Among them, we identified the transcription factor Forkhead box O3 (FoxO3) to be an essential regulator of the maintenance of pluripotency in dormant ESCs. Our study demonstrates that the transition into the dormant state endows residual undifferentiated cells with FoxO3-dependent and leukemia inhibitory factor/serum-independent pluripotency.


Assuntos
Diferenciação Celular , Proteína Forkhead Box O3/metabolismo , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Neurônios/citologia , Animais , Técnicas de Cultura de Células , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Autorrenovação Celular/efeitos dos fármacos , Células Cultivadas , Camundongos , Células-Tronco Embrionárias Murinas/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fator 3 de Transcrição de Octâmero/metabolismo , Quinolonas/farmacologia , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
11.
Elife ; 52016 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-27648578

RESUMO

The regulation of protein degradation is essential for maintaining the appropriate environment to coordinate complex cell signaling events and to promote cellular remodeling. The Autophagy linked FYVE protein (Alfy), previously identified as a molecular scaffold between the ubiquitinated cargo and the autophagic machinery, is highly expressed in the developing central nervous system, indicating that this pathway may have yet unexplored roles in neurodevelopment. To examine this possibility, we used mouse genetics to eliminate Alfy expression. We report that this evolutionarily conserved protein is required for the formation of axonal tracts throughout the brain and spinal cord, including the formation of the major forebrain commissures. Consistent with a phenotype reflecting a failure in axon guidance, the loss of Alfy in mice disrupts localization of glial guidepost cells, and attenuates axon outgrowth in response to Netrin-1. These findings further support the growing indication that macroautophagy plays a key role in the developing CNS.


Assuntos
Encéfalo/embriologia , Vias Neurais/embriologia , Neurônios/fisiologia , Proteínas de Transporte Vesicular/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Proteínas Relacionadas à Autofagia , Técnicas de Inativação de Genes , Camundongos Endogâmicos C57BL
12.
Clin Cancer Res ; 22(22): 5497-5505, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27185373

RESUMO

PURPOSE: There is a growing interest in using circulating tumor DNA (ctDNA) testing in patients with cancer. EXPERIMENTAL DESIGN: A total of 168 patients with diverse cancers were analyzed. Patients had digital next-generation sequencing (54 cancer-related gene panel including amplifications in ERBB2, EGFR, and MET) performed on their plasma. Type of genomic alterations, potential actionability, concordance with tissue testing, and patient outcome were examined. RESULTS: Fifty-eight percent of patients (98/168) had ≥1 ctDNA alteration(s). Of the 98 patients with alterations, 71.4% had ≥ 1 alteration potentially actionable by an FDA-approved drug. The median time interval between the tissue biopsy and the blood draw was 2.7 months for patients with ≥ 1 alteration in common compared with 14.4 months (P = 0.006) for the patients in whom no common alterations were identified in the tissue and plasma. Overall concordance rates for tissue and ctDNA were 70.3% for TP53 and EGFR, 88.1% for PIK3CA, and 93.1% for ERBB2 alterations. There was a significant correlation between the cases with ≥ 1 alteration with ctDNA ≥ 5% and shorter survival (median = 4.03 months vs. not reached at median follow-up of 6.1 months; P < 0.001). Finally, 5 of the 12 evaluable patients (42%) matched to a treatment targeting an alteration(s) detected in their ctDNA test achieved stable disease ≥ 6 months/partial remission compared with 2 of 28 patients (7.1%) for the unmatched patients, P = 0.02. CONCLUSIONS: Our initial study demonstrates that ctDNA tests provide information complementary to that in tissue biopsies and may be useful in determining prognosis and treatment. Clin Cancer Res; 22(22); 5497-505. ©2016 AACR.


Assuntos
DNA Tumoral Circulante/sangue , DNA Tumoral Circulante/genética , DNA de Neoplasias/sangue , Neoplasias/sangue , Neoplasias/patologia , DNA de Neoplasias/genética , Receptores ErbB/genética , Feminino , Genômica , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Biópsia Líquida/métodos , Masculino , Oncologia/métodos , Pessoa de Meia-Idade , Neoplasias/genética , Fosfatidilinositol 3-Quinases/genética , Receptor ErbB-2/genética , Estudos Retrospectivos , Proteína Supressora de Tumor p53/genética
14.
Photochem Photobiol Sci ; 11(10): 1524-7, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22932911

RESUMO

Upon photoirradiation of a stilbene-cored poly(glutamate) dendrimer, the photocrosslinking reaction preferentially occurred to produce the [2 + 2] cycloadduct in benzene. In addition, blue-shifted absorption spectra and a bisignate circular dichroism (CD) signal were observed, indicating that the aggregates of the stilbene core were chiral.

15.
J Nat Prod ; 75(5): 986-90, 2012 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-22583058

RESUMO

Jomthonic acid A (1), a new modified amino acid, was isolated from the culture broth of a soil-derived actinomycete of the genus Streptomyces. The structure and absolute configuration of 1 were determined by spectroscopic analyses and chemical conversion. Jomthonic acid A (1) induced differentiation of preadipocytes into mature adipocytes at 2-50 µM.


Assuntos
Adipócitos/efeitos dos fármacos , Aminoácidos/isolamento & purificação , Microbiologia do Solo , Streptomyces/química , Adipócitos/metabolismo , Aminoácidos/química , Aminoácidos/metabolismo , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular
16.
Curr Biol ; 22(11): 977-88, 2012 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-22560615

RESUMO

BACKGROUND: Sister chromatids are held together by the ring-shaped cohesin complex, which is loaded onto chromosomes before DNA replication. Cohesion between sister chromosomes is established during DNA replication, and it requires acetylation of the Smc3 subunit of cohesin by evolutionally conserved cohesin acetyltransferases (CoATs). However, how CoATs are recruited to chromatin and how cohesin acetylation is regulated remain unclear. RESULTS: We found that cohesin acetylation requires pre-RC-dependent chromatin loading of cohesin, but surprisingly, it is independent of DNA synthesis in Xenopus egg extracts. Immunodepletion experiments revealed that XEco2 is the CoAT responsible for Smc3 acetylation and sister chromatid cohesion. Recruitment of XEco2 onto chromatin was dependent on pre-RC assembly but was independent of cohesin loading and DNA synthesis. Two short N-terminal motifs, PBM-A and PBM-B, which are conserved among vertebrate Esco2/XEco2 homologs, were collectively essential for pre-RC-dependent chromatin association of XEco2, cohesin acetylation, and subsequent sister chromatid cohesion. The conserved PCNA-interacting protein box in XEco2 was largely dispensable for Smc3 acetylation but was partially required for cohesion. Interaction of acetylated cohesin with DNA was stabilized against salt-wash treatments after DNA replication. CONCLUSIONS: Our results demonstrate that pre-RC formation regulates chromatin association of XEco2 in Xenopus egg extracts. We propose that this reaction is critical to acetylate cohesin, whose DNA binding is subsequently stabilized by DNA replication.


Assuntos
Acetiltransferases/metabolismo , Proteínas de Ciclo Celular/metabolismo , Cromátides/fisiologia , Cromatina/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Xenopus/metabolismo , Acetilação , Sequência de Aminoácidos , Animais , Replicação do DNA , Feminino , Masculino , Dados de Sequência Molecular , Óvulo/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Xenopus , Coesinas
18.
Med Chem ; 7(4): 250-6, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21568875

RESUMO

Adiponectin, an adipose-derived protein, shows insulin-sensitizing, anti-diabetic and anti-atherogenic activities, which implies that the protein represents a potential target to improve lifestyle-related diseases like type 2 diabetes. Based on our hypothesis that agents that cause adipocyte differentiation could also act as adiponectin secretion enhancers, we screened butanol extracts of 96 fungus culture extracts for their differentiation-inducing activity in ST-13 preadipocytes. We found that the butanol extract of a fungus P16 culture extract possessed such an activity, and isolated norlichexanthone as an active compound through activity-guided fractionation. Oil red O staining showed that norlichexanthone induced adipogenesis in ST-13 cells. Its differentiation-inducing activity was supported by the observation that norlichexanthone dose-dependently increased the mRNA expression of fatty acid-binding protein and peroxisome proliferator activated receptor γ (PPARγ), markers of adipocyte differentiation. Western blot analysis demonstrated that the compound enhanced the secretion of adiponectin protein in a dose-dependent manner. An increase in mRNA expression of adiponectin was also observed in the norlichexanthone-treated ST-13 cells. Actinomycin D treatment blocked the enhancement of adiponectin mRNA expression by norlichexanthone, suggesting that it is the result of increased transcription. A luciferase reporter assay indicated that norlichexanthone was unlikely to be an agonist of PPARγ, implying that its action of mechanism might differ from those of thiazolidinediones which upregulate adiponectin expression via activation of PPARγ. These findings suggest the possibility that norlichexanthone has the potential to treat and/or prevent lifestyle-related diseases, including metabolic syndrome, type 2 diabetes, atherosclerosis and cardiovascular diseases.


Assuntos
Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Adiponectina/metabolismo , Hipoglicemiantes/farmacologia , PPAR gama/agonistas , Xantonas/farmacologia , Adipócitos/citologia , Adipócitos/metabolismo , Adiponectina/genética , Animais , Compostos Azo/metabolismo , Linhagem Celular , Corantes/metabolismo , Dactinomicina/farmacologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Relação Dose-Resposta a Droga , Proteínas de Ligação a Ácido Graxo/metabolismo , Fungos/metabolismo , Hipoglicemiantes/isolamento & purificação , Estilo de Vida , Camundongos , Terapia de Alvo Molecular , PPAR gama/biossíntese , Inibidores da Síntese de Proteínas/farmacologia , Transcrição Gênica/efeitos dos fármacos , Xantonas/isolamento & purificação
19.
Environ Mol Mutagen ; 52(3): 244-52, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20740625

RESUMO

Tumor development in the skin may be a multistep process where multiple genetic alterations occur successively. The p53 gene is involved in genome stability and thus is referred to as "the guardian of the genome." To better understand the antigenotoxic effects of p53 in ultraviolet light B (UVB)-induced mutagenesis, mutations were measured in the epidermis of UVB-irradiated p53(+/+) and p53(-/-) gpt delta mice. In the mouse model, point mutations and deletions are separately identified by the gpt and Spi(-) assays, respectively. The mice were exposed to UVB at single doses of 0.5, 1.0, or 2.0 kJ/m(2) . The mutant frequencies (MFs) were determined 4 weeks after the irradiation. All doses of UVB irradiation enhanced gpt MFs by about 10 times than that of unirradiated mice. There were no significant differences in gpt MFs and the mutation spectra between p53(+/+) and p53(-/-) mice. The predominant mutations induced by UVB irradiation were G:C to A:T transitions at dipyrimidines. In contrast, in unirradiated p53(-/-) mice, the frequencies of Spi(-) large deletions of more than 1 kb and complex-type deletions with rearrangements were significantly higher than those of the Spi(-) large deletions in p53(+/+) counterparts. The specific Spi(-) mutation frequency of more than 1 kb deletions and complex types increased in a dose-dependent manner in the p53(+/+) mice. However, no increase of such large deletions was observed in irradiated p53(-/-) mice. These results suggest that the antigenotoxic effects of p53 may be specific to deletions and complex-type mutations induced by double-strand breaks in DNA.


Assuntos
Sequência de Bases/efeitos da radiação , Deleção de Sequência , Pele/efeitos da radiação , Proteína Supressora de Tumor p53/metabolismo , Raios Ultravioleta , Animais , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pentosiltransferases/genética , Pentosiltransferases/metabolismo , Pele/metabolismo
20.
Cancer Sci ; 101(11): 2462-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20670297

RESUMO

Nobiletin is a citrus polymethoxyflavonoid that suppresses tumor growth and metastasis, both of which depend on angiogenesis. We recently identified nobiletin as a cell differentiation modulator. Because cell differentiation is a critical event in angiogenesis, it might be possible that nobiletin could exhibit antiangiogenic activity, resulting in suppression of these tumor malignant properties. To verify this possibility, we examined the antiangiogenic effects of nobiletin in vitro and in vivo. Nobiletin had concentration-dependent inhibitory effects on multiple functions of angiogenesis-related endothelial cells (EC); it suppressed the proliferation, migration and tube formation on matrigel of human umbilical vein EC (HUVEC) stimulated with endothelial cell growth supplement (ECGS), a mixture of acidic and basic fibroblast growth factors (FGFs). Gelatin zymography and northern blotting revealed that nobiletin suppressed pro-matrix metalloproteinase-2 (proMMP-2) production and MMP-2 mRNA expression in ECGS-stimulated HUVEC. Nobiletin also downregulated cell-associated plasminogen activator (PA) activity and urokinase-type PA mRNA expression. Furthermore, nobiletin inhibited angiogenic differentiation induced by vascular endothelial growth factor and FGF, an in vitro angiogenesis model. This inhibition was accompanied by downregulation of angiogenesis-related signaling molecules, such as extracellular signal-regulated kinase 1/2 and c-Jun N-terminal kinase, and transcriptional factors (c-Jun and signal transducer and activator of transcription 3), and activation of the caspase pathway. In a chick embryo chorioallantoic membrane assay, nobiletin showed an antiangiogenic activity, the ID(50) value being 10µg (24.9nmol) per egg. These results indicate that nobiletin is a novel antiangiogenic compound that exhibits its activity through combined inhibition of multiple angiogenic EC functions.


Assuntos
Proliferação de Células/efeitos dos fármacos , Membrana Corioalantoide/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Flavonas/farmacologia , Animais , Antioxidantes/farmacologia , Northern Blotting , Western Blotting , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Embrião de Galinha , Membrana Corioalantoide/irrigação sanguínea , Relação Dose-Resposta a Droga , Células Endoteliais/metabolismo , Células Endoteliais/fisiologia , Precursores Enzimáticos/genética , Precursores Enzimáticos/metabolismo , Fator 2 de Crescimento de Fibroblastos/farmacologia , Expressão Gênica/genética , Humanos , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Neovascularização Patológica/fisiopatologia , Neovascularização Fisiológica/efeitos dos fármacos , Neovascularização Fisiológica/fisiologia , Ativadores de Plasminogênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ativador de Plasminogênio Tipo Uroquinase/genética , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Fator A de Crescimento do Endotélio Vascular/farmacologia
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