Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Zhonghua Yi Xue Za Zhi ; 100(38): 3014-3017, 2020 Oct 20.
Artigo em Chinês | MEDLINE | ID: mdl-33086454

RESUMO

Objective: To investigate the effect of Na(+)/K(+)-ATPase inhibitor ouabain on the proliferation and division of liver cancer HepG2 cells, and to explore the anticancer mechanism. Methods: HepG2 cells were exposed with different concentrations of ouabain (0.1, 1, 10 µmol/L) for 24 h, the proliferation ability was appraised using CCK-8, and the HepG2 cells was as a control group. The status of chromosome separation was detected with cell immunofluorescence (ICC) coupled to confocal microscope. The expression levels of AURKA, mTOR, p-mTOR, ERK and p-ERK protein were analyzed using western blot. Results: After treating with 0.1, 1 and 10 µmol/L of ouabain for 24 h, the inhibitory rate of cells were (23.5±4.57)%, (49.80±5.32)%, and (72.10±5.62)%, respectively. Ouabain could significantly inhibit the proliferation of HepG2, and presented in a dose-dependent manner(F=32.8, P<0.05). The ICC results showed that the chromosome separation disorders occurred in HepG2 cells treated with 1 µmol/L for 24 h, and the spindle diameter of HepG2 cells with ouabain treatment was decreased significantly compared with the control group(t=9.58, P<0.05). The results of western blot showed that the expression levels of AURKA, p-mTOR and p-ERK expressions in HepG2 cells treated with 1 µmol/L of ouabain were significantly decreased compared with the control group(F=16.26, 8.32, 33.59, P<0.05). Ouabain inhibited the growth of hepatocellular carcinoma cells in nude mice(F=370.20, P<0.05). Conclusion: Ouabain can induce chromosome division disorder and inhibit the proliferation in liver cancer HepG2 cells by inhibiting AURKA signaling pathway.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Camundongos , Camundongos Nus , Ouabaína/farmacologia , Transdução de Sinais , ATPase Trocadora de Sódio-Potássio/metabolismo
2.
Oncogene ; 37(3): 389-402, 2018 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-28945223

RESUMO

Metabolic stress is a common phenomenon in solid tumors. Compensatory mechanisms to overcome metabolic stress (glucose deprivation) are vital to tumor cell survival. The histone demethylase Jumonji domain-containing protein 2B (JMJD2B) is vital for the growth and progression of various cancers. However, the role of JMJD2B during glucose deprivation remains unclear. Our aim was to examine the function of JMJD2B in glucose-deprived colon cancer cells and the involvement of extracellular signal-regulated kinase (ERK) and glucose transporter 1 (GLUT1). Our study demonstrated that JMJD2B expression was upregulated via ERK phosphorylation during glucose deprivation. Further, the cell viability assay showed that the effect of p-ERK on the viability of colon cancer cells was at least partly dependent on JMJD2B expression. Glucose deprivation increased interaction between JMJD2B and p-ERK, as demonstrated by the co-immunoprecipitation and fluorescence assays. Glucose deprivation also resulted in phosphorylation of JMJD2B by p-ERK, as shown by the immunoprecipitation assay and western blotting analysis. In addition, the phosphorylation of JMJD2B via p-ERK at Thr305, Ser352, Ser566 and Thr1065 contribute to JMJD2B stability. p-ERK stabilizes the JMJD2B protein level by protecting JMJD2B from ubiquitination and proteasome degradation. We found that knockdown of JMJD2B significantly impaired colon cancer cell viability, which is accompanied by a significant reduction in glucose uptake and lactate production. Furthermore, knockdown of JMJD2B after glucose deprivation caused decreased level of GLUT1 through increasing H3K9 tri-methylation levels on its promoter, demonstrated by chromatin immunoprecipitation assay. Moreover, targeting JMJD2B in xenograft tumors also decreased the GLUT1 level. Finally, a positive correlation was observed between p-ERK, JMJD2B and GLUT1 expression in 85 human colon cancer tissue specimens. These results indicated that p-ERK-mediated phosphorylation and stabilization of JMJD2B during glucose deprivation contributes to its role in glucose uptake and cell viability, which may be modulated through epigenetically upregulation of GLUT1.


Assuntos
Neoplasias do Colo/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação Neoplásica da Expressão Gênica , Transportador de Glucose Tipo 1/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Colo/patologia , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Metilação de DNA , Epigênese Genética , Técnicas de Silenciamento de Genes , Glucose/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Histonas/metabolismo , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Camundongos , Camundongos Nus , Fosforilação , Proteólise , RNA Interferente Pequeno , Estresse Fisiológico , Ubiquitinação , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Zhonghua Yi Xue Za Zhi ; 96(18): 1424-9, 2016 May 17.
Artigo em Chinês | MEDLINE | ID: mdl-27266350

RESUMO

OBJECTIVE: To observe the clinical characteristics of bone disease in patients with multiple myeloma (MM) and the clinical significance of monitoring bone metabolic markers. METHODS: The data of 178 MM cases newly diagnosed in Beijing Ji Shui Tan Hospital from January 2009 to June 2014 were reviewed to analysis the types and classification of bone disease and to observe the clinical characteristics of patients with different grades of bone disease. The levels of bone metabolic markers total procollagen type Ⅰ N-terminal peptide (tPINP) and ß C-terminal telopeptide of type Ⅰ collagen (ß-CTX) were monitored regularly in the two years following treatment in 66 cases. RESULTS: (1) Among the 178 newly diagnosed MM cases, 167 cases complained of pain in bones on first visit, 35 cases combined with hypercalcemia, 83 cases combined with osteoporosis, 154 cases combined with osteolytic bone destruction, and 73 cases combined with pathologic fracture. The most common osteolytic location was the spine. The most common fracture sites was the spine. (2) According to bone disease grading, the 178 cases were divided into group A (bone grade 0-2, n=51) and group B(bone grade 3-4, n=127). There were no significant differences between group A and group B in gender, median age, therapeutic effect/ineffec, median overall survival, median progress-free survival, mean serum lactic dehydrogenase, mean albumin, urine light chains and serum creatinine(all P>0.05). Compared with group A, group B had lower hemoglobin level[(99.78±29.93)vs (108.84±29.30) g/L], and higher blood calcium level[(2.47±0.40)vs (2.30±0.29) mmol/L], serum ß2-microglobuin level[(6.04±4.84)vs (4.12±3.97)mg/L], and bone marrow plasma cells percentage(33.30%±24.87% vs 23.51%±22.67%)(all P<0.05). (3) Before treatment, the levels of ß-CTX and tPINP in patients of group B(n=47) were higher than those in group A(n=19)(median 0.78 vs 0.42 µg/L, 60.95 vs 43.47 µg/L, both P<0.05). The ratio of ß-CTX /tPINP in group B was higher than that in group A (median 0.017 vs 0.012, P<0.05). After chemotherapy for 3 months, there were no differences in the level of tPINP compared with that before treatment in both group A and group B (both P>0.05), the level of ß-CTX decreased significantly compared with that before treatment in both groups(median 0.16 vs 0.42 µg/L, 0.26 vs 0.78 µg/L, both P<0.05); the ratio of ß-CTX /tPINP decreased significantly compared with that before treatment in both group A and in group B(median 0.008 vs 0.012, 0.011 vs 0.017, both P<0.05). There were no differences in the level of ß-CTX, tPINP and ß-CTX/tPINP ratio after treatment for 6 months, 1 year and 2 years compared with that after 3 months in both group A and group B (all P>0.05). (4)All patients were divided into two groups according to the therapeutic effect: effective group included patients who reach the effect of partial remission or better remission(n=48), while ineffective group included patients who did not reach the effect of partial remission(n=18). Before treatment there were no differences in the level of ß-CTX, tPINP and ß-CTX/tPINP ratio between the effective groupand the ineffective group (all P>0.05). After chemotherapy for 3 months, there were no differences in the level of tPINP compared with that before treatment in both effective group and ineffective group (all P>0.05), but the level of ß-CTX decreased significantly compared with that before treatment both in effective group and ineffective group (median 0.24 vs 0.60 µg/L, 0.44 vs 0.95 µg/L, both P<0.05). The ratio of ß-CTX /tPINP decreased significantly compared with that before treatment both in effective group and ineffective group (median 0.005 vs 0.012, 0.005 vs 0.011, both P<0.05). There were no differences in the level of ß-CTX, tPINP and ß-CTX/tPINP ratio after treatment for 6 months, 1 year and 2 years compared with that for 3 months both in effective group and ineffective group (all P>0.05). CONCLUSIONS: Pain in bones, osteolysis and pathological fracture are the most common clinical manifestations in myeloma-related bone disease. The severity of bone disease can reflect the tumor load, but may not affect the therapeutic effect and the overall survival. The bone metabolic markers tPINP and ß-CTX can be used to evaluate the severity of myeloma-related bone disease at diagnosis and to monitor the effect of treatment for bone disease.


Assuntos
Doenças Ósseas/complicações , Colágeno Tipo I/metabolismo , Mieloma Múltiplo/complicações , Fragmentos de Peptídeos/metabolismo , Peptídeos/metabolismo , Pró-Colágeno/metabolismo , Doenças Ósseas/diagnóstico , Doenças Ósseas/metabolismo , Osso e Ossos/metabolismo , Fraturas Ósseas/complicações , Humanos , Osteoporose/complicações , Osteoporose/metabolismo
4.
Invest Ophthalmol Vis Sci ; 42(11): 2547-53, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11581196

RESUMO

PURPOSE: To measure psychophysically the thresholds for motion detection in the nasal and temporal directions under monocular viewing conditions in monkeys reared under conditions of daily alternating monocular occlusion (AMO). The hypothesis was that motion perception would be asymmetric with more sensitivity for motion in the nasal direction. METHODS: Three monkeys subjected to AMO (AMO monkeys) and three normal monkeys were studied. All were trained with operant conditioning techniques to discriminate coherent from random motion in a random dot display. The percentage of dots in the display that moved either left or right was varied. Thresholds for motion detection of nasally directed and temporally directed stimuli were measured to determine whether the motion perception of AMO monkeys was asymmetric, as predicted. RESULTS: A two-factor analysis of variance revealed a statistically significant difference between treatment groups (normal versus AMO) and directions (nasal versus temporal) and a significant interaction. The interaction was due to a significant difference between nasal and temporal directions for the AMO group, but no significant difference for the normal group. Planned comparisons were performed based on each animal's best eye (eye most sensitive to nasal motion) and worst eye (eye least sensitive to temporal motion). No significant differences were found between the two groups in the best eyes' responses to the nasal direction, but the worst eyes' responses in the temporal direction were significantly poorer in the AMO group. A neural model that can account for these findings is based on a Hebbian teacher located in the nucleus of the optic tract that strengthens connections of a subpopulation of directionally selective cortical neurons. CONCLUSIONS: AMO rearing results in asymmetric motion perception. Thresholds for detecting nasally directed motion are normal, whereas thresholds for detecting temporally directed motion are deficient. These results demonstrate that motion-processing mechanisms in primates exhibit experience-dependent developmental neural plasticity. The locus of the neural plasticity could be a subpopulation of directionally selective neurons in the striate cortex (V1).


Assuntos
Percepção de Movimento/fisiologia , Transtornos da Percepção/fisiopatologia , Privação Sensorial/fisiologia , Visão Binocular/fisiologia , Córtex Visual/fisiopatologia , Animais , Macaca mulatta , Plasticidade Neuronal/fisiologia , Nistagmo Optocinético/fisiologia , Psicofísica , Acompanhamento Ocular Uniforme/fisiologia
5.
Zhongguo Yi Liao Qi Xie Za Zhi ; 25(3): 146-8, 2001 May.
Artigo em Chinês | MEDLINE | ID: mdl-12583283

RESUMO

Through mechanical analysis, it is discovered that the twined structure decides the amplification coefficient of the catgut tension. Many troubles of production can be explained with this mechanics model, and it could be used as a reference for medical sutures. The paper gives an accurate calculating formula for catgut design and its direct tensile strength through improving mechanics model. It can raise the material strength from 10 to over 31% depending on its twined structure.


Assuntos
Algoritmos , Categute/normas , Falha de Equipamento , Modelos Teóricos , Estresse Mecânico , Resistência à Tração
6.
J Comp Neurol ; 383(1): 73-81, 1997 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-9184987

RESUMO

We used quantitative autoradiography to determine whether the development of glutamate receptors correlates with the plastic period for monocular deprivation in rat visual cortex. To study glutamate receptors, we incubated sections of rat visual cortex with tritiated (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]-cyclohepten-5,10imin e maleate (MK-801), tritiated kainate, and tritiated amino-3-hydroxy-5-methyl-isoxazole-4-propionic acid (AMPA). [3H]MK-801 is a noncompetitive ligand for the N-methyl-D-aspartate (NMDA) receptor. [3H]kainate and [3H]AMPA are competitive ligands for non-NMDA receptors. To compare glutamate binding sites with a nonglutamate binding site, we studied [3H]muscimol, which binds to gamma-aminobutyric acid (GABA)A receptors. [3H]MK-801 binding was maximal at postnatal day 26 (P26) and decreased in adulthood. [3H]AMPA binding was maximal at P18. [3H]kainate binding and [3H]muscimol binding were not age dependent. Dark rearing partially prevented the age-dependent decrease in [3H]MK-801 binding but had no effect on [3H]kainate or [3H]AMPA binding. Dark rearing decreased muscimol binding in adult animals. These results suggest that NMDA receptors, but not other glutamate receptors or GABAA receptors, are likely to be critical for developmental plasticity in rat visual cortex.


Assuntos
Receptores de AMPA/metabolismo , Receptores de GABA/metabolismo , Receptores de Glutamato/metabolismo , Receptores de Ácido Caínico/metabolismo , Córtex Visual/crescimento & desenvolvimento , Córtex Visual/metabolismo , Animais , Autorradiografia , Escuridão , Maleato de Dizocilpina/metabolismo , Antagonistas de Aminoácidos Excitatórios/metabolismo , Agonistas GABAérgicos/metabolismo , Processamento de Imagem Assistida por Computador , Muscimol/metabolismo , Plasticidade Neuronal/fisiologia , Ratos
7.
Science ; 251(4995): 807-10, 1991 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-1990443

RESUMO

Differential translation of messenger RNA (mRNA) with stable secondary structure in the 5' untranslated leader may contribute to the dramatic changes in protein synthetic patterns that occur during oogenesis and early development. Plasmids that contained the bacterial gene chloramphenicol acetyltransferase and which encoded mRNA with (hpCAT) or without (CAT) a stable hairpin secondary structure in the 5' noncoding region were transcribed in vitro, and the resulting mRNAs were injected into Xenopus oocytes, eggs, and early embryos. During early oogenesis, hpCAT mRNA was translated at less than 3 percent of the efficiency of CAT mRNA. The relative translational potential of hpCAT reached 100 percent in the newly fertilized egg and returned to approximately 3 percent after the midblastula transition.


Assuntos
Biossíntese de Proteínas , RNA Mensageiro/genética , Xenopus laevis/genética , Animais , Sequência de Bases , Cloranfenicol O-Acetiltransferase/genética , Proteínas do Ovo/biossíntese , Proteínas do Ovo/genética , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Oogênese/genética , Plasmídeos , Xenopus laevis/embriologia
8.
Zhonghua Zhong Liu Za Zhi ; 8(4): 265-7, 1986 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-3757739

RESUMO

Nanao county, Guangdong province is a high incidence area of carcinoma of esophagus and gastric cardia carcinoma. By retrospective investigation of data in the past 14 years (1970 to 1983), the annual average crude mortality of carcinoma of esophagus and gastric cardia carcinoma was found to be 88.65/100,000, the age adjusted mortality of Chinese population was 82.91/100,000 and that of the world population was 113.09/100,000. The mortality of the male was 100.65/100,000 and of the female was 67.24/100,000 with the ratio of 1.38:1. As regards the relationship between the age and mortality, the highest rate occurs from 50 to 74. A higher mortality was also observed in the population engaged in salt production and fishing. The mortality was higher in the lower elevation areas than in the elevated regions.


Assuntos
Cárdia , Neoplasias Esofágicas/epidemiologia , Neoplasias Gástricas/epidemiologia , Adulto , Fatores Etários , Idoso , Neoplasias Esofágicas/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ocupações , Estudos Retrospectivos , Neoplasias Gástricas/mortalidade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...