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1.
Front Psychol ; 13: 1033065, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36571027

RESUMO

The present study examined the cross-lagged relationship between home numeracy practices (e.g., formal teaching, number games, and number application) and early mathematical skills (basic number processing, and arithmetic skills) among Chinese young children. A total of 155 children (82 boys; mean age = 67.49 months, SD = 3.58 months) were assessed with basic number processing and arithmetic skills at three timepoints during the kindergarten year, and their parents reported the frequency of parent-child numeracy activities. Main results from random-intercept cross-lagged panel models showed that, at the within-family level, earlier basic teaching activities uniquely predicted subsequent basic number processing, while both advanced teaching activities and number game activities at earlier timepoints predicted the following arithmetic skills. These results indicated a unidirectional effect from home numeracy practices on early mathematical skills during the early years.

2.
Gene ; 823: 146338, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35245640

RESUMO

We have previously reported that morroniside promoted motor activity after spinal cord injury (SCI) in rats. However, the mechanism by which morroniside induces recovery of injured spinal cord (SC) remains unknown. In the current study, RNA sequencing (RNA-seq) was employed to evaluate changes of gene expressions at the transcriptional level of the injured spinal cords in morroniside-administrated rats. Principal component analysis, analysis of enriched Gene Ontology (GO), enrichment analyses Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, and other bioinformatics analyses were executed to distinguish differentially expressed genes (DEGs). The results of RNA-seq confirmed the anti-inflammatory and anti-apoptotic effects of morroniside on injured SC tissues, and provided the basis for additional research of the mechanisms involving the protective effects of morroniside on SCI.


Assuntos
Anti-Inflamatórios/administração & dosagem , Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes/efeitos dos fármacos , Glicosídeos/administração & dosagem , Traumatismos da Medula Espinal/tratamento farmacológico , Animais , Anti-Inflamatórios/farmacologia , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Ontologia Genética , Glicosídeos/farmacologia , Análise de Componente Principal , Distribuição Aleatória , Ratos , Análise de Sequência de RNA , Traumatismos da Medula Espinal/etiologia , Traumatismos da Medula Espinal/genética
3.
Neurochem Int ; 148: 105105, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34147513

RESUMO

Spinal cord injury (SCI) is a disabling condition that often leads to permanent neurological deficits without an effective treatment. Reactive oxygen species (ROS) produced during oxidative stress play a vital role in the pathogenesis following SCI. The antioxidant morroniside is the main active component of the Chinese medicine Cornus officinalis. In recent years, it has been reported that morroniside has therapeutic effects on damage to multiple organs mediated by oxidative damage, but the effect of morroniside on SCI has not been reported. The purpose of this study was therefore to assess the therapeutic effect of morroniside on SCI, and to identify its underlying mechanism by direct intragastric administration immediately after SCI. Our study showed that morroniside treatment improved the functional recovery of rats following SCI. This behavioral improvement was associated with the higher survival in neurons and oligodendrocytes following SCI, which increased the capacity of injured spinal cord (SC) to form myelin and repair tissue, eventually contributing to improved neurological outcome. Furthermore, our study found that oxygen free radicals increased and antioxidant enzyme activity decreased in the injured SC. Interestingly, morroniside treatment decreased oxygen free radical levels and increased antioxidant enzyme activities. Together, our results suggested that morroniside may be an effective treatment for improving outcomes following SCI, and that its antioxidant activity may be one of the mechanisms by which morroniside exerts neuroprotective effects on SCI.


Assuntos
Glicosídeos/farmacologia , Fármacos Neuroprotetores/farmacologia , Traumatismos da Medula Espinal/tratamento farmacológico , Animais , Antioxidantes/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Cornus/química , Feminino , Locomoção , Neurônios/patologia , Oligodendroglia/patologia , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/patologia
4.
Neural Regen Res ; 16(9): 1836-1847, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33510091

RESUMO

Inflammation is a major cause of neuronal injury after spinal cord injury. We hypothesized that inhibiting caspase-1 activation may reduce neuroinflammation after spinal cord injury, thus producing a protective effect in the injured spinal cord. A mouse model of T9 contusive spinal cord injury was established using an Infinite Horizon Impactor, and VX-765, a selective inhibitor of caspase-1, was administered for 7 successive days after spinal cord injury. The results showed that: (1) VX-765 inhibited spinal cord injury-induced caspase-1 activation and interleukin-1ß and interleukin-18 secretion. (2) After spinal cord injury, an increase in M1 cells mainly came from local microglia rather than infiltrating macrophages. (3) Pro-inflammatory Th1Th17 cells were predominant in the Th subsets. VX-765 suppressed total macrophage infiltration, M1 macrophages/microglia, Th1 and Th1Th17 subset differentiation, and cytotoxic T cells activation; increased M2 microglia; and promoted Th2 and Treg differentiation. (4) VX-765 reduced the fibrotic area, promoted white matter myelination, alleviated motor neuron injury, and improved functional recovery. These findings suggest that VX-765 can reduce neuroinflammation and improve nerve function recovery after spinal cord injury by inhibiting caspase-1/interleukin-1ß/interleukin-18. This may be a potential strategy for treating spinal cord injury. This study was approved by the Animal Care Ethics Committee of Bengbu Medical College (approval No. 2017-037) on February 23, 2017.

5.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 34(6): 572-576, 2018 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-31032595

RESUMO

OBJECTIVE: To investigate the effects of hydrogen sulfide (H2S) on renal fibrosis in diabetic rats and explore its mechanism. METHODS: Male Sprague-Dawley rats were randomly divided into normal control (NC) group, a diabetic control (DC) group, diabetes mellitus (DM)+sodium hydrosulfide (NaHS) group and DM+DL-propargylglycine (PAG) group, with 8 rats in each group.Type 1 diabetes was induced in the respective groups by a single intraperitoneal (i.p.) injection of streptozotocin.From the fifth week, rats in the DM+NaHS and DM+PAG groups were injected (i.p.) with 56 µmol/kg NaHS and 40 mg/kg PAG once a day, respectively.After treatment for 4 weeks, the levels of fasting blood glucose (FBG), blood urea nitrogen (BUN) and serum creatinine (SCr) were detected.The deposition of renal collagen fibers was observed by Masson staining, and collagen volume fraction (CVF) was calculated.The ultrastructural change of renal tissue was observed by transmission electron microscopy.The levels of interleukin-1ß (IL-1ß), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and hydroxyproline (Hyp) in renal tissues were detected using the kits.The expression levels of TGF-ß1, Smad3, phosphorylated (p)-Smad3 and collagen-IV (col-IV) in renal tissues were detected using Western blot. RESULTS: Compared with the NC group, the levels of FBG, BUN, SCr, CVF, IL-1ß, IL-6, TNF-α and Hyp were increased; the deposition of renal collagen fibers and the ultrastructural damage were aggravated; the levels of TGF-ß1, Smad3, p-Smad3, p-Smad3/Smad3 and col-IV were increased in the DC group.Compared with the DC group, excluding FBG, the aforementioned indices were improved in the DM+NaHS group; the aforementioned indices were further aggravated in the DM+PAG group. CONCLUSIONS: H2S attenuated renal fibrosis in diabetic rats, and the mechanism might be associated with the reduction of the release of proinflammatory cytokines, downregulation of the TGF-ß1/Smad3 pathway, and inhibition of excessive accumulation of col-IV.


Assuntos
Diabetes Mellitus Experimental , Animais , Fibrose , Sulfeto de Hidrogênio , Masculino , Ratos , Ratos Sprague-Dawley , Estreptozocina , Fator de Crescimento Transformador beta1
6.
Neural Regen Res ; 12(7): 1079-1085, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28852389

RESUMO

Limited by the tiny structure of axons, the effects of these axonal hyperpolarizing inputs on neuronal activity have not been directly elucidated. Here, we imitated these processes by simultaneously recording the activities of the somas and proximal axons of cortical pyramidal neurons. We found that spikes and subthreshold potentials propagate between somas and axons with high fidelity. Furthermore, inhibitory inputs on axons have opposite effects on neuronal activity according to their temporal integration with upstream signals. Concurrent with somatic depolarization, inhibitory inputs on axons decrease neuronal excitability and impede spike generation. In addition, following action potentials, inhibitory inputs on an axon increase neuronal spike capacity and improve spike precision. These results indicate that inhibitory inputs on proximal axons have dual regulatory functions in neuronal activity (suppression or facilitation) according to neuronal network patterns.

7.
Int J Mol Med ; 39(3): 603-612, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28204825

RESUMO

Oxidative stress-induced cell injury has been linked to the pathogenesis of neurodegenerative disorders such as spinal cord injury, Parkinson's disease, and multiple sclerosis. Morroniside is an antioxidant derived from the Chinese herb Shan-Zhu-Yu. The present study investigated the neuroprotective effect of morroniside against hydrogen peroxide (H2O2)-induced cell death in SK-N-SH human neuroblastoma cells. H2O2 increased cell apoptosis, as determined by flow cytometry and Hoechst 33342 staining. This effect was reversed by pretreatment with morroniside at concentrations of 1-100 µM. The increase in intracellular reactive oxygen species (ROS) generation and lipid peroxidation induced by H2O2 was also abrogated by morroniside. H2O2 induced a reduction in mitochondrial membrane potential, increased caspase-3 activity, and caused downregulation of B cell lymphoma-2 (Bcl-2) and upregulation of Bcl-2-associated X protein (Bax) expression. These effects were blocked by morroniside pretreatment. Thus, morroniside protects human neuroblastoma cells against oxidative damage by inhibiting ROS production while suppressing Bax and stimulating Bcl-2 expression, thereby blocking mitochondrial-mediated apoptosis. These results indicate that morroniside has therapeutic potential for the prevention and treatment of neurodegenerative diseases.


Assuntos
Glicosídeos/farmacologia , Peróxido de Hidrogênio/farmacologia , Neuroblastoma/metabolismo , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Caspase 3/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Glicosídeos/química , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Metaloproteinases da Matriz/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Fármacos Neuroprotetores/química , Oxidantes/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
8.
Neurobiol Dis ; 94: 196-204, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27370227

RESUMO

Oligodendrocyte (OL) replacement is a promising treatment strategy for spinal cord injury (SCI). However, the poor survival of transplanted OLs or their precursors and inhibition of axonal regeneration are two major challenges with this approach. Our previous study showed that Schwann cells (SCs) promoted survival, proliferation, and migration of transplanted OL progenitor cells (OPCs) and neurological recovery. Remyelination is an important basis for functional recovery following spinal cord injury. It has been reported that myelin gene regulatory factor (MRF), a transcriptional regulator which specifically is expressed in postmitotic OLs within the CNS, is essential for OL maturation and CNS myelination. In the present study, we investigated whether co-transplantation of MRF-overexpressing OPCs (MRF-OPCs) and SCs could improve functional recovery in a rat model of contusional SCI. MRF overexpression had no effect on OPC survival or migration, but stimulated the differentiation of OPCs both in vitro and in vivo. Co-transplantation of MRF-OPCs and SCs increased myelination and tissue repair after SCI, leading to the recovery of neurological function. These results indicate that co-transplantation of MRF-OPCs and SCs may be an effective treatment strategy for SCI.


Assuntos
Células-Tronco Neurais/citologia , Células Precursoras de Oligodendrócitos/citologia , Recuperação de Função Fisiológica/fisiologia , Células de Schwann/citologia , Traumatismos da Medula Espinal/fisiopatologia , Fatores de Transcrição/metabolismo , Animais , Feminino , Bainha de Mielina/metabolismo , Células Precursoras de Oligodendrócitos/metabolismo , Ratos Sprague-Dawley , Fatores de Transcrição/genética
9.
Food Chem ; 192: 499-515, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26304378

RESUMO

Allii Macrostemonis Bulbus (AMB) is increasingly becoming popular as an edible vegetable or traditional folk medicine in East Asia due to its great health and medicinal properties. However, due to a lack of available research, the effective material of AMB still remains unknown. In this study, we applied a strategy utilising ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UPLC/Q-TOF-MS) to investigate chemical profiles of AMB. In addition, metabolite profiles of five representative single steroidal saponins as well as AMB were investigated. Moreover, the metabolic features of saponins in AMB were summarised. After oral administration, the saponins underwent massive phase I and phase II metabolism. Sequential deglycosylation metabolism in rat intestine was the main metabolic pathway of the steroidal saponins, while oxidation, dehydrogenation, glucuronic acid reactions in liver also take part in further modification. These results expand our knowledge about the metabolism of AMB.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Saponinas/análise , Espectrometria de Massas em Tandem/métodos , Administração Oral , Animais , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/metabolismo , Mucosa Intestinal/metabolismo , Fígado/metabolismo , Masculino , Desintoxicação Metabólica Fase I , Desintoxicação Metabólica Fase II , Raízes de Plantas/química , Ratos , Ratos Sprague-Dawley , Saponinas/administração & dosagem , Saponinas/metabolismo
10.
Sci Rep ; 5: 8718, 2015 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-25732721

RESUMO

Conditioned medium from mesenchymal stem cells (MSC-CM) may represent a promising alternative to MSCs transplantation, however, the low concentrations of growth factors in non-activated MSC-CM hamper its clinical application. Recent data indicated that the paracrine potential of MSCs could be enhanced by inflammatory factors. Herein, we pre-activated bone-marrow-derived MSCs under radiation-induced inflammatory condition (MSC(IEC-6(IR))) and investigated the evidence and mechanism for the differential effects of MSC-CM(IEC-6(IR)) and non-activated MSC-CM on radiation-induced intestinal injury (RIII). Systemic infusion of MSC-CM(IEC-6(IR)), but not non-activated MSC-CM, dramatically improved intestinal damage and survival of irradiated rats. Such benefits may involve the modulation of epithelial regeneration and inflammation, as indicated by the regeneration of intestinal epithelial/stem cells, the regulation of the pro-/anti-inflammatory cytokine balance. The mechanism for the superior paracrine efficacy of MSC(IEC-6(IR)) is related to a higher secretion of regenerative, immunomodulatory and trafficking molecules, including the pivotal factor IGF-1, induced by TNF-α, IL-1ß and nitric oxide partially via a heme oxygenase-1 dependent mechanism. Together, our findings suggest that pre-activation of MSCs with TNF-α, IL-1ß and nitric oxide enhances its paracine effects on RIII via a heme oxygenase-1 dependent mechanism, which may help us to maximize the paracrine potential of MSCs.


Assuntos
Meios de Cultivo Condicionados/farmacologia , Interleucina-1beta/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Óxido Nítrico/metabolismo , Comunicação Parácrina , Fator de Necrose Tumoral alfa/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Heme Oxigenase-1/metabolismo , Inflamação/etiologia , Inflamação/metabolismo , Mediadores da Inflamação/metabolismo , Fator de Crescimento Insulin-Like I/farmacologia , Enteropatias/tratamento farmacológico , Enteropatias/mortalidade , Enteropatias/patologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Mucosa Intestinal/efeitos da radiação , Doses de Radiação , Lesões Experimentais por Radiação/tratamento farmacológico , Lesões Experimentais por Radiação/mortalidade , Lesões Experimentais por Radiação/patologia , Ratos , Regeneração/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo
11.
Asian Pac J Cancer Prev ; 15(15): 6301-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25124615

RESUMO

Cervical cancer is one the most common malignancies among females. In recent years, its incidence rate has shown a rising trend in some countries so that development of anticancer drugs for cervical cancer is an urgent priority. In our recent anticancer drug discovery screen, 1, 2-di (quinazolin-4-yl)diselane (LG003) was found to possess wide spectrum anticancer efficacy. In the present work, the in vitro anticancer activity of LG003 was evaluated in the SiHa cervical cancer cell line. Compared with commercial anticancer drugs 10-hydroxycamptothecin, epirubicin hydrochloride, taxol and oxaliplatin, LG003 showed better anticancer activity. Furthermore, inhibition effects were time- and dose-dependent. Morphological observation exhibited LG003 treatment results in apoptosis like shrinking and blebbing, and cell membrane damage. Lactate dehydrogenase release assay revealed that LG003 exerts such effects in SiHa cells through a physiology pathway rather than cytotoxicity, which suggests that title compound LG003 can be a potential candidate agent for cervical cancer.


Assuntos
Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Compostos Organosselênicos/química , Quinazolinas/química , Neoplasias do Colo do Útero/tratamento farmacológico , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Western Blotting , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Citometria de Fluxo , Humanos , Técnicas In Vitro , L-Lactato Desidrogenase/metabolismo , Compostos Organosselênicos/farmacologia , Quinazolinas/farmacologia , Células Tumorais Cultivadas
12.
Int J Neurosci ; 122(8): 458-65, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22463720

RESUMO

The previous studies suggested that some subpopulations of T lymphocytes against central nervous system (CNS) antigens, such as myelin basic protein (MBP), are neuroprotective. But there were few reports about the effect of these T cells on axon regeneration. In this study, the neonatally thymectomied (Tx) adult rats which contain few T lymphocytes were subjected to spinal cord hemisection and then passively immunized with MBP-activated T cells (MBP-T). The regeneration and dieback of transected axons of cortico-spinal tract (CST) were detected by biotin dextran amine (BDA) tracing. The behavioral assessments were performed using the Basso, Beattie, and Bresnahan locomotor rating scale. We found that passive transferring of MBP-T could attenuate axonal dieback. However, no significant axon regeneration and behavioral differences were observed among the normal, Tx and sham-Tx (sTx) rats with or without MBP-T passive immunization. These results indicate that passive transferring of MBP-T cells can attenuate axonal dieback and promote neuroprotection following spinal cord injury (SCI), but may not promote axon regeneration.


Assuntos
Imunização Passiva/métodos , Recuperação de Função Fisiológica/imunologia , Traumatismos da Medula Espinal/imunologia , Traumatismos da Medula Espinal/terapia , Linfócitos T/imunologia , Análise de Variância , Animais , Animais Recém-Nascidos , Antígenos CD/metabolismo , Biotina/análogos & derivados , Proliferação de Células , Citocinas/metabolismo , Dextranos , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Lateralidade Funcional , Locomoção/fisiologia , Proteína Básica da Mielina/imunologia , Regeneração Nervosa/imunologia , Tratos Piramidais/metabolismo , Tratos Piramidais/patologia , Tratos Piramidais/fisiopatologia , Ratos , Ratos Sprague-Dawley , Linfócitos T/classificação , Linfócitos T/metabolismo , Timectomia
13.
Neurotherapeutics ; 9(2): 422-45, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22173726

RESUMO

Neural stem cell (NSC) transplantation is a major focus of current research for treatment of spinal cord injury (SCI). However, it is very important to promote the survival and differentiation of NSCs into myelinating oligodendrocytes (OLs). In this study, myelin basic protein-activated T (MBP-T) cells were passively immunized to improve the SCI microenvironment. Olig2-overexpressing NSCs were infected with a lentivirus carrying the enhanced green fluorescent protein (GFP) reporter gene to generate Olig2-GFP-NSCs that were transplanted into the injured site to differentiate into OLs. Transferred MBP-T cells infiltrated the injured spinal cord, produced neurotrophic factors, and induced the differentiation of resident microglia and/or infiltrating blood monocytes into an "alternatively activated" anti-inflammatory macrophage phenotype by producing interleukin-13. As a result, the survival of transplanted NSCs increased fivefold in MBP-T cell-transferred rats compared with that of the vehicle-treated control. In addition, the differentiation of MBP-positive OLs increased 12-fold in Olig2-GFP-NSC-transplanted rats compared with that of GFP-NSC-transplanted controls. In the MBP-T cell and Olig2-GFP-NSC combined group, the number of OL-remyelinated axons significantly increased compared with those of all other groups. However, a significant decrease in spinal cord lesion volume and an increase in spared myelin and behavioral recovery were observed in Olig2-NSC- and NSC-transplanted MBP-T cell groups. Collectively, these results suggest that MBP-T cell adoptive immunotherapy combined with NSC transplantation has a synergistic effect on histological and behavioral improvement after traumatic SCI. Although Olig2 overexpression enhances OL differentiation and myelination, the effect on functional recovery may be surpassed by MBP-T cells.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/biossíntese , Ativação Linfocitária/fisiologia , Proteína Básica da Mielina/metabolismo , Proteínas do Tecido Nervoso/biossíntese , Células-Tronco Neurais/metabolismo , Recuperação de Função Fisiológica/fisiologia , Traumatismos da Medula Espinal/metabolismo , Linfócitos T/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Diferenciação Celular/fisiologia , Células Cultivadas , Feminino , Regulação da Expressão Gênica , Proteína Básica da Mielina/biossíntese , Proteínas do Tecido Nervoso/genética , Células-Tronco Neurais/transplante , Fator de Transcrição 2 de Oligodendrócitos , Ratos , Ratos Sprague-Dawley , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/cirurgia , Transplante de Células-Tronco/métodos , Linfócitos T/fisiologia
14.
Carcinogenesis ; 31(9): 1552-60, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20622005

RESUMO

BACKGROUND AND AIMS: The expression of pancreatic-duodenal homeobox 1 (PDX1) in gastric cancer is aberrantly reduced. The aim of this study was to elucidate the regulation of DNA methylation and histone acetylation at the promoter for PDX1 silencing in gastric cancer. METHODS: PDX1 expression in response to demethylation and acetylation was detected in human gastric cancer cell lines by reverse transcription-polymerase chain reaction (PCR) and western blot. Four CpG islands within the 5'-flanking region of PDX1 gene were analyzed with their transcription activities being detected by dual luciferase assay. Promoter hypermethylation was identified in gastric cancer cell lines and cancer tissues by methylation-specific PCR or bisulfite DNA sequencing PCR analysis. Histone acetylation was determined by chromatin immunoprecipitation (ChIP) assay. RESULTS: Demethylation by 5'-aza-2'-deoxycytidine (5'-aza-dC) and/or acetylation by trichostatin A (TSA) restored PDX1 expression in gastric cancer cells. Hypermethylation was found in four CpG islands in six of seven cancer cell lines. However, only the distal CpG island located in the promoter fragment of PDX1, F383 (c.-2063 to -1681 nt upstream of the ATG start codon) displayed significant transcriptional activity that could be suppressed by SssI methylase and increased by 5'-aza-dC and TSA. More than 70% of the single CpG sites in F383 were methylated with hypermethylation of F383 fragment more common in gastric cancerous tissues compared with the paired normal tissues (P < 0.05). ChIP assay showed F383 was also associated with low hypoacetylation level of the histones. CONCLUSION: Promoter hypermethylation and histone hypoacetylation contribute to PDX1 silencing in gastric cancer.


Assuntos
Metilação de DNA , Inativação Gênica , Proteínas de Homeodomínio/genética , Neoplasias Gástricas/genética , Transativadores/genética , Acetilação , Antimetabólitos Antineoplásicos/farmacologia , Azacitidina/farmacologia , Western Blotting , Imunoprecipitação da Cromatina , Ilhas de CpG , Regulação Neoplásica da Expressão Gênica , Inibidores de Histona Desacetilases/farmacologia , Proteínas de Homeodomínio/metabolismo , Humanos , Ácidos Hidroxâmicos/farmacologia , Regiões Promotoras Genéticas , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transativadores/metabolismo , Células Tumorais Cultivadas
15.
Nan Fang Yi Ke Da Xue Xue Bao ; 28(3): 436-7, 2008 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-18359706

RESUMO

OBJECTIVE: To investigate the effects of the two-valence vaccine consisting of Helicobacter pylori (H. pylori) catalase and urease subunit UreB in preventing H. pyloriinfection in mice. METHODS: C57BL/6 mice were divided into 7 groups and immunized with intragastric administration of catalase and UreB (both 100 microg) plus cholera toxin (CT, 2 microg), catalase (100 microg) plus CT (2 microg), UreB (100 microg) plus CT (2 microg), catalase (100 microg), UreB (100 microg), CT (2 microg), or PBS, respectively, once a week for 4 consecutive weeks. Two weeks after the last immunization, all the mice were challenged by live H. pylori, and sacrificed 4 weeks after the challenge to obtain the gastric mucosa samples for detecting H. pylori using semi-quantitative bacterial culture assay. RESULTS: The total protection rate in mice immunized with the two-valence vaccine, single-valence vaccine of catalase, and single-valence vaccine of UreB was 83.3% (20/24), 41.7% (10/24) and 54.2% (13/24), respectively, and the rate in the other 4 groups were all 0. The H. pyloricolony density in mice with vaccination was significantly lower than that of other 4 groups (P<0.05). The total protection rate and H. pylori colony density differed significantly between the two-valence vaccination group and the single-valence vaccination groups (P<0.05). CONCLUSION: The two-valence vaccine consisting of catalase, UreB and adjuvant has better immunoprotective effects than the single-valence vaccines.


Assuntos
Vacinas Bacterianas/imunologia , Catalase/imunologia , Infecções por Helicobacter/prevenção & controle , Helicobacter pylori/imunologia , Urease/imunologia , Animais , Proteínas de Bactérias/imunologia , Infecções por Helicobacter/imunologia , Helicobacter pylori/enzimologia , Imunização/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Aleatória
16.
Helicobacter ; 12(2): 164-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17309754

RESUMO

BACKGROUND: Prevalence of Helicobacter pylori infection is inversely associated with socioeconomic conditions. The aim of the study was to evaluate changes in the seroprevalence of H. pylori infection during 1993-2003 in Guangzhou, a representative city of southern China with quick improvement in socioeconomy. METHODS: From March to August 2003, sera were collected from 1471 healthy persons (760 male and 711 female subjects, aged 3-92 years) undergoing annual routine health examination in Guangzhou. H. pylori infection was checked by enzyme-linked immunosorbent assay (ELISA). RESULTS: In 2003, the overall prevalence rate of H. pylori infection was 47% with no gender difference (p > .05). Children aged 1-5 years had the prevalence rate of 19.4%. The prevalence rate then increased steadily with annual infection rate of approximately 1% after this age, reaching a plateau of approximately 55% after the age of 50 years. The peak seroprevalence rate was 63.2% at 40-50 years. Comparing the prevalence rate of H. pylori infection in 2003 with data obtained in 1993, statistically significant decrease of H. pylori infection rate ranged from 11.4 to 18.0% in different age groups was found. The overall age-standardized H. pylori seroprevalence rate was 62.5% in 1993 and 49.3% in 2003. The seroprevalence of H. pylori was found to be significantly decreased over a time span of 10 years (p < .001). CONCLUSIONS: Our data suggest that the seroprevalence of H. pylori infection has significantly decreased during the 10-year period in Guangzhou. This change may be attributable to the improvement in socioeconomic conditions in this city.


Assuntos
Infecções por Helicobacter/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , China/epidemiologia , Feminino , Infecções por Helicobacter/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Soroepidemiológicos , Fatores Socioeconômicos
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