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1.
Zhonghua Yi Xue Za Zhi ; 101(2): 131-136, 2021 Jan 12.
Artigo em Chinês | MEDLINE | ID: mdl-33455129

RESUMO

Objective: To analyze the correlations among different common scales for evaluating the severity of the first-visit Charcot-Marie-Tooth disease (CMT), and explore the cross-sectional characteristics of neurological dysfunction in patients with four common genotypes (CMT1A, CMT1X, CMT2A and MPZ-related CMT) at their first visits. Methods: A total of 117 genetically confirmed CMT patients (aged ≥10 years) from the Department of Neurology of the Third Xiangya Hospital from 2009 to 2019 were included in the study, which consisted of 45 CMT1A, 41 CMT1X, 19 CMT2A, and 12 MPZ-related CMT patients. Clinical data of these patients at first visits were collected and neurological deficits were evaluated by Charcot-Marie-Tooth Neuropathy Score (CMTNS), Charcot-Marie-Tooth Examination Score (CMTES), Overall Neuropathy Limitation Scale (ONLS) and Functional Disability Scale (FDS). Spearman's correlation was performed to analyze the relationship between CMTNS, CMTES, ONLS and FDS. The age of onset, duration of disease, scores of CMTNS, CMTES, ONLS and FDS were compared among four genotypes. Results: In the 117 CMT patients, the male to female ratio was 1.79/1, and the age of onset was (19±13) years. The duration of disease was 10(3, 15) years, and the scores of CMTNS, CMTES, ONLS and FDS were 11.4±6.2, 8.8±5.7, 2.7±1.4 and 2.6±1.3, respectively. There was a significant correlation between CMTES, ONLS, FDS and CMTNS in the overall CMT patients and four subtypes respectively (r≥0.40, P<0.05). CMTNS, CMTES and ONLS scores of four subtypes showed positive correlations with duration of disease (P<0.05), but FDS scores of CMT1A, CMT1X and MPZ-related CMT patients exhibited no correlation with duration of disease (P>0.05) at their first visits. The age of onset in CMT2A patients was younger than that of the patients with the other three genotypes (P<0.05), furthermore, the scores of four scales in early-onset CMT2A patients were higher than those of adult-onset type CMT2A patients (CMTNS: P=0.031, CMTES: P=0.048, ONLS: P=0.042, FDS: P=0.047). In CMT1X patients, the males had higher scores than those of females for all four scales (CMTNS: P=0.028, CMTES: P=0.014, ONLS: P=0.023, FDS: P=0.002). Conclusions: CMTNS, CMTES and ONLS could be used in natural history studies and clinical trials according to the different clinical situations. In the four genotypes, CMT2A patients have younger age of onset, and the earlier the age of onset, the severer the dysfunction. Moreover, male CMT1X patients relatively have severer neurological dysfunction than female patients.


Assuntos
Doença de Charcot-Marie-Tooth , Adolescente , Adulto , Doença de Charcot-Marie-Tooth/genética , Criança , Estudos Transversais , Feminino , Genótipo , Humanos , Masculino , Adulto Jovem
2.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 32(5): 537-541, 2020 Jan 17.
Artigo em Chinês | MEDLINE | ID: mdl-33185071

RESUMO

Protein kinase A (PKA) is an important intracellular substance that regulates substance metabolism and biological functions, which exerts a wide range of biological effects through phosphorylation of specific serine/threonine residues in specific proteins. PKA plays an important role in the cAMP signaling pathway, and is involved in various life activities of parasites. Therefore, investigating the role of PKA in the life activities of parasites may provide insights into the development of novel anti-parasitic targets. The review mainly describes the structure and function of PKA and its role in life activities of parasites.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico , Parasitos/enzimologia , Transdução de Sinais , Animais , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Fosforilação
3.
Nanoscale ; 6(11): 5754-61, 2014 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-24681667

RESUMO

In this work, reduced graphene oxide (r-GO) and graphite nanosheet (GN) were obtained via the chemical approach. Furthermore, r-GO composites and GN composites were prepared with a paraffin wax host. r-GO composites show high dielectric properties and electromagnetic interference shielding efficiency (EMI SE). Compared with the GN composites, the loss tangent and EMI SE of the r-GO composites with the same mass ratio are enhanced ∼5 to 10 times and ∼3 to 10 times, respectively. The enhanced attenuation capacity arises from higher specific surface area, clustered defects and residual bonds of the r-GOs, which increase the polarization loss, scattering and conductivity of the composite. Moreover, the higher conductivity of r-GO composites leads to higher EMI SE compared with that of GN composites. These results suggest that r-GOs are highly promising fillers for microwave attenuation in the carbon family and that r-GO composites are high-performance EMI shielding materials with application anticipated to many fields.

4.
J Microsc ; 211(Pt 3): 219-29, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12950471

RESUMO

The effect of several data collection and processing choices has been examined for high-resolution electron back-scatter pattern (EBSP) investigation of a highly deformed sample. The results were compared with a transmission electron microscope (TEM) investigation of the same sample. The estimated dislocation cell size was examined as a function of data cleaning strategy, line intercept vs. reconstruction method, critical misorientation angle definition and step-size. The best agreement with the TEM results was obtained using a modified relative reconstruction algorithm on fine step-size maps allowing some of the noise in the data to be overcome. Step sizes of up to one-quarter the average cell size yielded similar values for the estimated average cell size. As a result of the mixture of both high- and low-angle boundaries, single diffraction condition TEM images may give larger cell size estimates than the EBSP data. Orientation noise in the EBSP data, however, still limits the extent to which quantitative information can be extracted.

5.
J Biol Chem ; 276(45): 42485-91, 2001 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-11551940

RESUMO

Peroxisome proliferators, which function as peroxisome proliferator-activated receptor alpha (PPARalpha) agonists, induce peroxisomal, microsomal, and mitochondrial fatty acid oxidation enzymes, in conjunction with peroxisome proliferation, in liver cells. Sustained activation of PPARalpha leads to the development of liver tumors in rats and mice. The assertion that synthetic PPARalpha ligands pose negligible carcinogenic risk to humans is attributable, in part, to the failure to observe peroxisome proliferation in human hepatocytes. To explore the mechanism(s) of species-specific differences in response to PPARalpha ligands, we determined the functional competency of human PPARalpha in vivo and compared its potency with that of mouse PPARalpha. Recombinant adenovirus that expresses human or mouse PPARalpha was produced and administered intravenously to PPARalpha-deficient mice. Human as well as mouse PPARalpha fully restored the development of peroxisome proliferator-induced immediate pleiotropic responses, including peroxisome proliferation and enhanced expression of genes involved in lipid metabolism as well as nonperoxisomal genes, such as CD36, Ly-6D, Rbp7, monoglyceride lipase, pyruvate dehydrogenase kinase-4, and C3f, that have been identified recently to be up-regulated in livers with peroxisome proliferation. These studies establish that human PPARalpha is functionally competent and is equally as dose-sensitive as mouse PPARalpha in inducing peroxisome proliferation within the context of mouse liver environment and that it can heterodimerize with mouse retinoid X receptor, and this human PPARalpha-mouse retinoid X receptor chimeric heterodimer transcriptionally activates mouse PPARalpha target genes in a manner qualitatively similar to that of mouse PPARalpha.


Assuntos
Fígado/metabolismo , Peroxissomos/metabolismo , Receptores Citoplasmáticos e Nucleares/fisiologia , Fatores de Transcrição/fisiologia , Animais , Divisão Celular/efeitos dos fármacos , Regulação da Expressão Gênica , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oxirredução , Peroxissomos/efeitos dos fármacos , Pirimidinas/farmacologia , RNA Mensageiro/análise
6.
Proc Natl Acad Sci U S A ; 98(18): 10380-5, 2001 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-11517327

RESUMO

The nuclear receptor coactivators participate in the transcriptional activation of specific genes by nuclear receptors. In this study, we report the isolation of a nuclear receptor coactivator-interacting protein from a human liver cDNA library by using the coactivator peroxisome proliferator-activated receptor-interacting protein (PRIP) (ASC2/AIB3/RAP250/NRC/TRBP) as bait in a yeast two-hybrid screen. Human PRIP-interacting protein cDNA has an ORF of 2,556 nucleotides, encodes a protein with 852 amino acids, and contains a 9-aa VVDAFCGVG methyltransferase motif I and an invariant GXXGXXI segment found in K-homology motifs of many RNA-binding proteins. The gene encoding this protein, designated PRIP-interacting protein with methyltransferase domain (PIMT), is localized on chromosome 8q11 and spans more than 40 kb. PIMT mRNA is ubiquitously expressed, with a high level of expression in heart, skeletal muscle, kidney, liver, and placenta. Using the immunofluorescence localization method, we found that PIMT and PRIP proteins appear colocalized in the nucleus. PIMT strongly interacts with PRIP under in vitro and in vivo conditions, and the PIMT-binding site on PRIP is in the region encompassing amino acids 773-927. PIMT binds S-adenosyl-l-methionine, the methyl donor for methyltransfer reaction, and it also binds RNA, suggesting that it is a putative RNA methyltransferase. PIMT enhances the transcriptional activity of peroxisome proliferator-activated receptor gamma and retinoid-X-receptor alpha, which is further stimulated by coexpression of PRIP, implying that PIMT is a component of nuclear receptor signal transduction apparatus acting through PRIP. Definitive identification of the specific substrate of PIMT and the role of this RNA-binding protein in transcriptional regulation remain to be determined.


Assuntos
Metiltransferases/genética , Metiltransferases/metabolismo , Proteína D-Aspartato-L-Isoaspartato Metiltransferase , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , tRNA Metiltransferases/genética , tRNA Metiltransferases/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Células COS , Clonagem Molecular , Primers do DNA/genética , DNA Complementar/genética , Humanos , Metiltransferases/química , Camundongos , Dados de Sequência Molecular , Estrutura Terciária de Proteína , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/química , S-Adenosilmetionina/metabolismo , Homologia de Sequência de Aminoácidos , Distribuição Tecidual , Fatores de Transcrição/metabolismo , Transcrição Gênica , tRNA Metiltransferases/química
7.
Gene Expr ; 9(4-5): 173-81, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11444527

RESUMO

Spontaneous peroxisome proliferation-related pleiotropic responses occurring in the liver of mice lacking peroxisomal fatty acyl-CoA oxidase (AOX-/-) are attributed to sustained activation of peroxisome proliferator-activated receptor alpha (PPARalpha) by its putative natural ligands that require AOX for their metabolism. In this study, using a gene expression screen, we show that Ly-6 (lymphocyte antigen 6 complex, locus D; mouse ThB), which belongs to a distinctive family of low molecular weight phosphatidyl inositol anchored cell surface glycoproteins, is upregulated in mouse liver with peroxisome proliferation. Increases in Ly-6D mRNA levels are observed in AOX-/- mouse liver with spontaneous peroxisome proliferation and also in the liver of wild-type mice treated with synthetic peroxisome proliferators. Peroxisome proliferators failed to increase hepatic Ly-6D mRNA levels in mice lacking PPARalpha (PPARalpha-/-), suggesting a regulatory role for PPARalpha in the induction of Ly-6D. These observations suggest that changes in certain cell surface proteins also form part of the pleiotropic responses associated with peroxisome proliferation.


Assuntos
Antígenos Ly/genética , Fígado/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Regulação para Cima , Acil-CoA Oxidase , Animais , Relação Dose-Resposta a Droga , Deleção de Genes , Hibridização In Situ , Fígado/citologia , Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oxirredutases/genética , Oxirredutases/metabolismo , Proliferadores de Peroxissomos/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Tempo , Regulação para Cima/efeitos dos fármacos
8.
Exp Cell Res ; 268(1): 70-6, 2001 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-11461119

RESUMO

Mice deficient in fatty acyl-CoA oxidase (AOX(-/-)), the first enzyme of the peroxisomal beta-oxidation system, develop specific morphological and molecular changes in the liver characterized by microvesicular fatty change, increased mitosis, spontaneous peroxisome proliferation, increased mRNA and protein levels of genes regulated by peroxisome proliferator-activated receptor alpha (PPARalpha), and hepatocellular carcinoma. Based on these findings it is proposed that substrates for AOX function as ligands for PPARalpha. In this study we examined the sequential changes in morphology and gene expression in the liver of wild-type and AOX(-/-) mice at Embryonic Day 17.5, and during postnatal development up to 2 months of age. In AOX(-/-) mice high levels of expression of PPARalpha-responsive genes in the liver commenced on the day of birth and persisted throughout the postnatal period. We found no indication of PPARalpha activation in the livers of AOX(-/-) mice at embryonic age E17.5. In AOX(-/-) mice microvesicular fatty change in liver cells was evident at 7 days. At 2 months of age livers showed extensive steatosis and the presence in the periportal areas of clusters of hepatocytes with abundant granular eosinophilic cytoplasm rich in peroxisomes. These results suggest that the biological ligands for PPARalpha vis a vis substrates for AOX either are not functional in fetal liver or do not cross the placental barrier during the fetal development and that postnatally they are likely derived from milk and diet.


Assuntos
Isomerases , Fígado/metabolismo , Oxirredutases/deficiência , Receptores Citoplasmáticos e Nucleares/metabolismo , Fatores de Transcrição/metabolismo , 3-Hidroxiacil-CoA Desidrogenases/genética , 3-Hidroxiacil-CoA Desidrogenases/metabolismo , Acetil-CoA C-Aciltransferase/genética , Acetil-CoA C-Aciltransferase/metabolismo , Acil-CoA Oxidase , Envelhecimento/metabolismo , Animais , Animais Recém-Nascidos , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Enoil-CoA Hidratase/genética , Enoil-CoA Hidratase/metabolismo , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Regulação da Expressão Gênica no Desenvolvimento , Immunoblotting , Hibridização In Situ , Isoenzimas/genética , Isoenzimas/metabolismo , Ligantes , Fígado/citologia , Fígado/embriologia , Camundongos , Camundongos Knockout , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/metabolismo , Oxirredutases/genética , Oxirredutases/metabolismo , Enzima Bifuncional do Peroxissomo , Peroxissomos/patologia , Peroxissomos/ultraestrutura , RNA Mensageiro/metabolismo
9.
Gene Expr ; 9(6): 291-304, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11764000

RESUMO

Peroxisome proliferators, which function as peroxisome proliferator-activated receptor-alpha (PPARalpha) agonists, are a group of structurally diverse nongenotoxic hepatocarcinogens including the fibrate class of hypolipidemic drugs that induce peroxisome proliferation in liver parenchymal cells. Sustained activation of PPARalpha by these agents leads to the development of liver tumors in rats and mice. To understand the molecular mechanisms responsible for the pleiotropic effects of these agents, we have utilized the cDNA microarray to generate a molecular portrait of gene expression in the liver of mice treated for 2 weeks with Wy-14,643, a potent peroxisome proliferator. PPARalpha activation resulted in the stimulation of expression (fourfold or greater) of 36 genes and decreased the expression (fourfold or more decrease) of 671 genes. Enhanced expression of several genes involved in lipid and glucose metabolism and many other genes associated with peroxisome biogenesis, cell surface function, transcription, cell cycle, and apoptosis has been observed. These include: CYP2B9, CYP2B10, monoglyceride lipase, pyruvate dehydrogenase-kinase-4, cell death-inducing DNA-fragmentation factor-alpha, peroxisomal biogenesis factor 11beta, as well as several cell recognition surface proteins including annexin A2, CD24, CD39, lymphocyte antigen 6, and retinoic acid early transcript-gamma, among others. Northern blotting of total RNA extracted from the livers of PPARalpha-/- mice and from mice lacking both PPARalpha and peroxisomal fatty acyl-CoA oxidase (AOX), that were fed control and Wy-14,643-containing diets for 2 weeks, as well as time course of induction following a single dose of Wy-14,643, revealed that upregulation of genes identified by microarray procedure is dependent upon peroxisome proliferation vis-à-vis PPARalpha. However, cell death-inducing DNA-fragmentation factor-alpha mRNA, which is increased in the livers of wild-type mice treated with peroxisome proliferators, was not enhanced in AOX-/- mice with spontaneous peroxisome proliferation. These observations indicate that the activation of PPARalpha leads to increased and decreased expression of many genes not associated with peroxisomes, and that delayed onset of enhanced expression of some genes may be the result of metabolic events occurring secondary to PPARalpha activation and alterations in lipid metabolism.


Assuntos
Fígado/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Receptores Citoplasmáticos e Nucleares/genética , Fatores de Transcrição/genética , Animais , DNA Complementar , Perfilação da Expressão Gênica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pirimidinas/farmacologia
10.
Zhongguo Zhong Yao Za Zhi ; 25(6): 338-41, 2000 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-12512420

RESUMO

OBJECTIVE: To isolate the mycorrhizal fungi from the roots of wild Dendribium candidum and D. nobile collected from Yunnan and Sichuan provinces and determine their biological activities. METHOD: The isolation was completed using solidified potato dextrose agar (PDA, Difco) of plates and the biological activities were tested by means of symbiotic germination of fungus-seedlings. RESULTS: 25 Species of mycorrhizal fungi were obtained and most of them belong to Basidiomycotina and Deuteromycotina. The preliminary biological activity test has shown that of these fungi 5 species help promote the seed germination of D. candidun, 7 species can establish the symbiotical relationship with seedlings of D. candium and D. nobile, and 3 species can stimulate the growth of seedlings of the two medicinal plants. CONCLUSION: Isolation and screening of fungi helpful to the growth and development of Dendrobium is important in the production of the herb.


Assuntos
Dendrobium/microbiologia , Micorrizas/isolamento & purificação , Dendrobium/crescimento & desenvolvimento , Micorrizas/fisiologia , Raízes de Plantas/microbiologia , Sementes/crescimento & desenvolvimento , Simbiose/fisiologia
11.
Gene Expr ; 8(4): 231-46, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10794525

RESUMO

We have previously reported the cloning of rat deoxyuridine triphosphate nucleotidohydrolase (dUTPase) cDNA and demonstrated that the full-length protein as well as the N-terminal 62-amino acid peptide interacts with peroxisome proliferator-activated receptor alpha (PPARalpha). We now report the cloning of mouse dUTPase cDNA and show that it contains a 162-amino acid open reading frame, encoding a protein with a predicted Mr of 17,400 and differs from rat cDNA, which contains additional 43 amino acids at the N-terminal end. Unlike rat dUTPase, mouse dUTPase failed to bind PPARalpha. An evaluation of 205 amino acid containing rat dUTPase cDNA revealed that the N-terminal 43 extra amino acid segment contains an LXXLL signature motif, considered necessary and sufficient for the binding of several cofactors with nuclear receptors, and its absence in murine dUTPase possibly accounts for the differential binding of these enzymes to PPARalpha. In situ hybridization and immunohistochemical studies revealed that, in the adult mouse, dUTPase is expressed at high levels in proliferating cells of colonic mucosa, and of germinal epithelium in testis. At 9.5-day mouse embryonic development, dUTPase expression is predominantly in developing neural epithelium, and hepatic primordium, and in later developmental stages (11.5-, 13.5-, and 15.5-day embryo), the expression began to be localized to the liver, kidney, gut epithelium, thymus, granular layer of the cerebellum, and olfactory epithelium. We also show that the murine dUTPase gene comprises 6 exons and the 5'-flanking region of -1479 to -27, which exhibited high promoter activity, contains a typical TATA box and multiple cis-elements such as Sp-1, AP2, AP3, AP4, Ker1, RREB, and CREB binding sites. These observations suggest the existence of variants of dUTPase, some of which may influence nuclear receptor function during development and differentiation, in addition to catalyzing the hydrolysis of dUTP to dUMP.


Assuntos
Pirofosfatases/genética , Receptores Citoplasmáticos e Nucleares/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Sítios de Ligação/genética , Clonagem Molecular , Camundongos , Dados de Sequência Molecular , Especificidade de Órgãos , Pirofosfatases/metabolismo , Ratos , Receptores Citoplasmáticos e Nucleares/metabolismo , Alinhamento de Sequência , Análise de Sequência , Especificidade da Espécie
12.
Zhongguo Yao Li Xue Bao ; 20(7): 601-3, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10678121

RESUMO

AIM: To study the efficacy of huperzine-A capsules (Hup) on memory and learning performance of adolescent students. METHODS: Using double-blind and matched pair method, 34 pairs of junior middle school students complaining of memory inadequacy were divided into two groups by normal psychological health inventory (PHI), similar memory quotient (MQ), same sex and class. The Hup group was administrated orally 2 capsules of Hup (each contains Hup 50 micrograms) b.i.d., and the placebo group was given 2 capsules of placebo (starch and lactose inside) b.i.d. for 4 wk. RESULTS: At the end of trial, the Hup group's MQ (115 +/- 6) was more than that of the placebo group (104 +/- 9, P < 0.01), and the scores of Chinese language lesson in the Hup group were elevated markedly too. CONCLUSION: The Hup capsules enhance the memory and learning performance of adolescent students.


Assuntos
Inibidores da Colinesterase/farmacologia , Aprendizagem/efeitos dos fármacos , Memória/efeitos dos fármacos , Sesquiterpenos/farmacologia , Adolescente , Adulto , Alcaloides , Cápsulas , Método Duplo-Cego , Feminino , Humanos , Masculino , Análise por Pareamento , Escalas de Wechsler
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