Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
1.
Zhonghua Yan Ke Za Zhi ; 58(10): 843-847, 2022 Oct 11.
Artigo em Chinês | MEDLINE | ID: mdl-36220661

RESUMO

High myopia is an important cause of low vision and blindness in the world, most of which are characterized by the prolongation of the axial length, accompanied by various degenerative changes of fundus posterior pole, especially in the optic disc area and peripapillary structures, such as optic disc tilt, optic cup and rim changes, chorioretinal atrophy, posterior staphyloma and intrachoroidal cavitation, and so on. This article reviews the optic disc morphological features and peripapillary structure changes of high myopia, in order to reveal the pathogenesis of high myopia and provide new ideas for finding more effective prevention and treatment methods.


Assuntos
Doenças da Coroide , Miopia , Disco Óptico , Doenças da Esclera , Fundo de Olho , Humanos , Miopia/patologia , Disco Óptico/patologia , Doenças da Esclera/patologia , Tomografia de Coerência Óptica
2.
Zhonghua Yi Xue Za Zhi ; 101(17): 1262-1268, 2021 May 11.
Artigo em Chinês | MEDLINE | ID: mdl-34865396

RESUMO

Objective: To investigate the clinical value of dual-channel contrast-enhanced ultrasound (DCUS) in the classification of hilar cholangiocarcinoma and the diagnosis of the etiology of low obstructive jaundice. Methods: The data of 114 patients with obstructive jaundice examined by the Department of Ultrasound of Lanzhou University Second Hospital from October 2018 to February 2020 were retrospectively collected. There were 60 males and 54 females, aged 37~84 (63±10) years. All patients underwent preoperative transvenous contrast-enhanced ultrasound (CEUS), intraoperative puncture needles, postoperative ultrasound-guided percutaneous transhepatic cholangiocarcinography (UG-PTC) and three-dimensional ultrasound cholangiography (3D-USC) through an external drainage tube, known as DCUS. The classification of hilar cholangiocarcinoma and the nature of low biliary tract obstruction were determined according to the characteristics of DCUS images. All patients who have received DCUS underwent magnetic resonance cholangiopancreatography (MRCP) and X-ray cholangiography. X-ray cholangiography was used as the gold standard for classification of hilar cholangiocarcinoma, and the accuracy of US, CEUS and DCUs was analyzed. Low obstructive jaundice was characterized by surgical pathology as the gold standard, and the diagnostic efficacy of conventional ultrasound (US), CEUS and DCUs was analyzed. At the same time, the receiver operating characteristic (ROC) curve was used to compare the efficacy of MRI+MRCP and DCUS in determination of the nature of low biliary obstruction. Results: The coincidence rates of US, CEUS, and DCUS in the classification of hilar cholangiocarcinoma and X-ray cholangiography were: 75.6% (34/45), 82.2% (37/45), and 93.3% (42/45), respectively. The coincidence rates of US, CEUS, and DCUS in the determination of the nature of low biliary obstruction and surgical pathology were 56.5% (39/69), 82.6% (57/69), and 85.5% (59/69), respectively. Compared with conventional ultrasound, CEUS had no statistically significant difference in the diagnosis of hilar cholangiocarcinoma (P=0.438), and DCUS had statistically significant difference in the diagnosis of hilar cholangiocarcinoma (P=0.039).ROC curve analysis suggested that the cut-off value of MRI+MRCP grade and DCUS grade for diagnosing benign and malignant low biliary obstruction were both 2.5; the area under the curve (AUC) were 0.897 and 0.906, respectively (both P<0.01); sensitivity were 77.5% and 93.1%, respectively; and the specificity were 87.5% and 82.8%, respectively. Conclusion: The value of DCUS in the classification of hilar cholangiocarcinoma and the qualitative diagnosis of low biliary tract obstruction was comparable to that of X-ray cholangiography and MRCP. DCUS had important clinical application value in the classification of hilar cholangiocarcinoma and the etiological diagnosis of low obstructive jaundice.


Assuntos
Neoplasias dos Ductos Biliares , Colestase , Tumor de Klatskin , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Feminino , Humanos , Masculino , Estudos Retrospectivos , Ultrassonografia
3.
Neoplasma ; 67(3): 604-613, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32266816

RESUMO

Papillary thyroid carcinoma (PTC) is the prevalent histotype of thyroid cancer, with increasing incidence worldwide. MicroRNAs (miRNAs) could play an important role in the development and progression of human cancers. Interestingly, miR-326 was validated as one of the downregulated miRNAs in PTC. Therefore, it is necessary to research the function of miR-326 involved in the progression of PTC. In the current study, we detected the downregulation of miR-326 in PTC tissues and cell lines. The miR-326 overexpression or knockdown was conducted in TPC-1 or HTh83 PTC cells. miR-326 mimics decreased the proliferation, clone formation ability and caused G1-phase accumulation. In addition, the reduction of migration and invasion abilities was induced by miR-326 mimics. Western blot analysis showed that the cells with miR-326 mimics exhibited the inhibition of vimentin and N-cadherin, as well as enhancement of E-cadherin. Importantly, miR-326 could directly target mitogen activated protein kinase 1 (MAPK1) and epidermal growth factor receptor 4 (ERBB4). MAPK1 or ERBB4 overexpression rescued the effects of miR-326 on proliferation, migration, and invasion in PTC cells. Notably, miR-326 reduced tumorigenesis in vivo, including the decrease of tumor volume and weight, suppression of Ki-67, N-cadherin, MAPK1 and ERBB4. In all, these results might provide a new therapeutic target for the diagnosis of PTC.


Assuntos
Carcinoma Papilar/patologia , MicroRNAs/genética , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Carcinoma Papilar/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Proteína Quinase 1 Ativada por Mitógeno , Invasividade Neoplásica , Receptor ErbB-4 , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/genética
5.
Eur J Orthop Surg Traumatol ; 28(6): 1089-1094, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29453752

RESUMO

PURPOSE: Patients with an upper brachial plexus lesion can suffer from dysfunction, joint deformities and instability of the shoulder. The goal of this study was to determine pain, shoulder function, patient satisfaction and muscle strength in shoulder arthrodesis in patients with an upper brachial plexus lesion more than 15 years after surgery. METHODS: We retrospectively studied 12 patients with a brachial plexus lesion of mean age 46 years (27-61). At a mean of 19.8 years (15.4-30.3) after shoulder arthrodesis, patient-reported outcome measures (PROMs), range of motion (e.g., active and passive), patient satisfaction, strength of the affected and non-affected side (e.g., maximum isometric strength in Newton in forward and retroflexion, ab- and adduction, internal and external rotation) and position of fusion were obtained. PROMS consisted of the Visual Analogue Scale (VAS; 0-100, 0 being painless) for pain and the Disabilities of the Arm, Shoulder and Hand Score (DASH; 0-100, 0 being the best score) for function. RESULTS: At latest follow-up, the median VAS pain score was 49 (0-96) and 0 for, respectively, the affected and unaffected side. The DASH was 15 (8-46), meaning a reasonable to good function of the upper extremity. Active and passive retroflexion was significantly different (p = 0.028). All subjects stated that in the same situation they would undergo a shoulder arthrodesis again. The unaffected side was significantly stronger in every direction. Arthrodesis showed position of fusion of 31° (12-70) abduction, 20° (10-50) forward flexion and 22° (- 14 to 58) internal rotation. The unaffected side was significantly (p ≤ 0.05) stronger in every movement direction. CONCLUSION: At a mean of 20 years after shoulder arthrodesis, patients with an upper brachial plexus lesion are still satisfied with a good to moderate functional improvement. LEVEL OF EVIDENCE III: A retrospective cohort study.


Assuntos
Artrodese , Neuropatias do Plexo Braquial/cirurgia , Articulação do Ombro/cirurgia , Adulto , Artralgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular , Medidas de Resultados Relatados pelo Paciente , Satisfação do Paciente , Projetos Piloto , Amplitude de Movimento Articular , Recuperação de Função Fisiológica , Estudos Retrospectivos , Resultado do Tratamento
6.
Br J Cancer ; 106(7): 1320-30, 2012 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-22453125

RESUMO

BACKGROUND: Side population (SP) cells and their relationship to stem cell-like properties have been insufficiently studied in colorectal cancer (CRC). MicroRNAs (miRNAs) have attracted much attention but their roles in the maintenance of SP phenotype remain unclear. METHODS: The SPs from CRC cell lines and primary cell cultures were analysed for stem cell-like properties. MiRNA microarray analysis identified miR-328 as a potential stemness miRNA of SP phenotype. The level of miR-328 expression in clinical samples and its correlation with SP fraction were determined. Gain-of-function and loss-of-function studies were performed to examine its roles in cancer stem-like SP cells. Furthermore, bioinformatics prediction and experimental validation were used to identify miR-328 target genes. RESULTS: The SP cells sorted from CRC possess cancer stem cell (CSC)-like properties, including self-renewal, differentiation, resistance to chemotherapy, invasive and strong tumour formation ability. MiR-328 expression was significantly reduced in SP cells compared with Non-SP cells (P<0.05). Moreover, miR-328 expression was downregulated in CRC (n=33, P<0.05) and low miR-328 expression tend to correlate with high SP fraction (n=15, r=0.6559, P<0.05, Pearson's correlation). Functional studies indicated that miR-328 expression affects the number of SP cells. In addition, miR-328 overexpression reversed drug resistance and inhibited cell invasion of SP cells. Furthermore, luciferase reporter assay demonstrated that miR-328 directly targets ABCG2 and MMP16 and affects the levels of mRNA and protein expression in SP cells. CONCLUSION: These findings indicate that CRC contain cancer stem-like SP cells. MiR-328 has an important role in maintaining cancer stem-like SP phenotype that may be a potential target for effective CRC therapy.


Assuntos
Neoplasias Colorretais/genética , MicroRNAs/fisiologia , Células-Tronco Neoplásicas/fisiologia , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Diferenciação Celular , Linhagem Celular Tumoral , Transformação Celular Neoplásica , Neoplasias Colorretais/patologia , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica , Humanos , Metaloproteinase 16 da Matriz/genética , MicroRNAs/metabolismo , Invasividade Neoplásica , Proteínas de Neoplasias/genética
7.
QJM ; 115(3): 140-147, 2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33367838

RESUMO

BACKGROUND: Previous studies have shown that lipid accumulation product (LAP) was associated with the risk of cardiometabolic disease. It is not clear whether LAP could be used as a marker to identify metabolic syndrome (MetS) among Chinese ethnic groups. AIM: To assess the reliability of LAP as a maker to identify MetS among Dong adults. DESIGN: Population-based cross-sectional study. METHOD: We included 6494 Dong individuals (1403 patients) aged 30-79 years from southwest China. MetS was established by Chinese Diabetes Society. Logistic regression model was utilized to calculate odds ratios (ORs) and 95% confidence intervals (CIs). Receiver operating characteristic (ROC) curve was utilized to calculate area under the ROC curve (AUC) and 95% CIs to obtain the identification ability for MetS. RESULTS: The risk of MetS was increased with per 5 units increase of LAP (OR 1.37 [95% CI, 1.34-1.39]). Similar results were found in subgroup analyses and sensitivity analyses. Clustered metabolic risk associated with per 5 units increase of LAP was observed for people with 1 (OR 1.59 [95% CI, 1.53-1.65]), 2 (2.15 [2.06-2.24]), 3 (2.59 [2.48-2.71]), 4 (2.81 [2.69-2.95]) and 5 (3.03 [2.87-3.21]) MetS components. LAP presented higher AUC (0.915 [95% CI, 0.907-0.923]) than other included obesity indices (P < 0.05). CONCLUSION: These data support evidence that LAP was related to the risk of MetS, had a high AUC and could be a reliable index for identifying MetS patients among Dong adults in Chinese.


Assuntos
Produto da Acumulação Lipídica , Síndrome Metabólica , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Índice de Massa Corporal , China/epidemiologia , Estudos Transversais , Etnicidade , Síndrome Metabólica/diagnóstico , Síndrome Metabólica/epidemiologia , Reprodutibilidade dos Testes , Fatores de Risco , Curva ROC
8.
Ann Plast Surg ; 65(4): 430-6, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20798625

RESUMO

The study was performed to find out a promising injectable composite scaffold for cartilage tissue engineering. By using a composite of allogenous cartilage microparticle acellular tissue matrix (CMACTM) and fibrin glue (Fg) as injectable scaffold materials, tissue-engineered cartilage was constructed in vivo, and the effects of which on the repair of porcine articular cartilage defects were observed. CMACTM was obtained from domestic pigs. The chondrocytes were prepared from experimental mini-type pigs and expanded in vitro. Fg was used as a scaffold material. The composite of CMACTM, second-passage chondrocytes, and Fg was replanted to the articular cartilage defective regions in autologous mini-type pig by injection. At 12 weeks after replantation, samples were collected and analyzed by general observation and histologic staining.The constructed tissue-engineered cartilage exhibited a good efficiency in the repair of articular cartilage defects. Cells in the constructed tissue-engineered cartilage grew well and were able to secrete cartilaginous matrix. The tissue-engineered cartilage showed a better biologic performance than the control. A composite of allogenous CMACTM and Fg was a promising injectable scaffold for cartilage tissue engineering, which could be used to repair articular cartilage defects by a minimally invasive procedure.


Assuntos
Cartilagem Articular/cirurgia , Condrócitos/transplante , Engenharia Tecidual/métodos , Alicerces Teciduais , Análise de Variância , Animais , Materiais Biocompatíveis , Cartilagem/citologia , Cartilagem/transplante , Cartilagem Articular/fisiopatologia , Condrócitos/citologia , Modelos Animais de Doenças , Rejeição de Enxerto , Sobrevivência de Enxerto , Regeneração Tecidual Guiada , Articulação do Joelho , Distribuição Aleatória , Valores de Referência , Sensibilidade e Especificidade , Sus scrofa , Suínos , Coleta de Tecidos e Órgãos , Transplante Homólogo
9.
Braz J Med Biol Res ; 49(6)2016 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-27240294

RESUMO

This study aims to explore the effect of microRNA-21 (miR-21) on the proliferation of human degenerated nucleus pulposus (NP) by targeting programmed cell death 4 (PDCD4) tumor suppressor. NP tissues were collected from 20 intervertebral disc degeneration (IDD) patients, and from 5 patients with traumatic spine fracture. MiR-21 expressions were tested. NP cells from IDD patients were collected and divided into blank control group, negative control group (transfected with miR-21 negative sequences), miR-21 inhibitor group (transfected with miR-21 inhibitors), miR-21 mimics group (transfected with miR-21 mimics) and PDCD4 siRNA group (transfected with PDCD4 siRNAs). Cell growth was estimated by Cell Counting Kit-8; PDCD4, MMP-2,MMP-9 mRNA expressions were evaluated by qRT-PCR; PDCD4, c-Jun and p-c-Jun expressions were tested using western blot. In IDD patients, the expressions of miR-21 and PDCD4 mRNA were respectively elevated and decreased (both P<0.05). The miR-21 expressions were positively correlated with Pfirrmann grades, but negatively correlated with PDCD4 mRNA (both P<0.001). In miR-21 inhibitor group, cell growth, MMP-2 and MMP-9 mRNA expressions, and p-c-Jun protein expressions were significantly lower, while PDCD4 mRNA and protein expressions were higher than the other groups (all P<0.05). These expressions in the PDCD4 siRNA and miR-21 mimics groups was inverted compared to that in the miR-21 inhibitor group (all P<0.05). MiR-21 could promote the proliferation of human degenerated NP cells by targeting PDCD4, increasing phosphorylation of c-Jun protein, and activating AP-1-dependent transcription of MMPs, indicating that miR-21 may be a crucial biomarker in the pathogenesis of IDD.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Proliferação de Células/fisiologia , MicroRNAs/metabolismo , Núcleo Pulposo/metabolismo , Proteínas de Ligação a RNA/metabolismo , Adulto , Idoso , Proteínas Reguladoras de Apoptose/análise , Proteínas Reguladoras de Apoptose/genética , Western Blotting , Contagem de Células , Células Cultivadas , Feminino , Expressão Gênica , Humanos , Degeneração do Disco Intervertebral/metabolismo , Luciferases , Masculino , Metaloproteinase 2 da Matriz/análise , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/análise , Metaloproteinase 9 da Matriz/genética , MicroRNAs/análise , MicroRNAs/genética , Pessoa de Meia-Idade , Núcleo Pulposo/citologia , RNA Mensageiro/análise , Proteínas de Ligação a RNA/análise , Proteínas de Ligação a RNA/genética , Valores de Referência , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fraturas da Coluna Vertebral/metabolismo , Fatores de Tempo
10.
J Comp Neurol ; 356(1): 115-31, 1995 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-7629306

RESUMO

In the primate striate cortex, cytochrome oxidase (CO)-rich puffs differ from CO-poor interpuffs in their metabolic levels and physiological properties. The neurochemical basis for their metabolic and physiological differences is not well understood. The goal of the present study was to examine the relationship between the distribution of gamma aminobutyric acid (GABA)/non-GABA synapses and CO levels in postsynaptic neuronal profiles and to determine whether or not a difference existed between puffs and interpuffs. By combining CO histochemistry and postembedding GABA immunocytochemistry on the same ultrathin sections, the simultaneous distribution of the two markers in individual neuronal profiles was quantitatively analyzed. In both puffs and interpuffs, GABA-immunoreactive (GABA-IR) neurons were the only cell type that received both non-GABA-IR (presumed excitatory) and GABA-IR (presumed inhibitory) axosomatic synapses, and they had three times as many mitochondria darkly reactive for CO than non-GABA-IR neurons, which received only GABA-IR axosomatic synapses. GABA-IR neurons and terminals in puffs had a larger mean size, about twice as many darkly reactive mitochondria, and a higher ratio of non-GABA-IR to GABA-IR axosomatic synapses than those in interpuffs (2.3:1 vs. 1.6:1; P < 0.01). There were significantly more synapses of both non-GABA-IR and GABA-IR types in the neuropil of puffs than of interpuffs; however, the ratio of non-GABA-IR to GABA-IR synapses was significantly higher in puffs (2.86:1) than in interpuffs (2.08:1; P < 0.01). Our results are consistent with the hypothesis that the level of oxidative metabolism in postsynaptic neurons and neuronal processes is tightly governed by the strength and proportion of excitatory over inhibitory synapses. Thus, the present results suggest that (1) GABA-IR neurons in the macaque striate cortex have a higher level of oxidative metabolism than non-GABA ones because their somata receive direct excitatory synapses and their terminals are more tonically active; (2) the higher proportion of presumed excitatory synapses in puffs imposes a greater energy demand there than in interpuffs; and (3) excitatory synaptic activity may be more prominent in puffs than in interpuffs because puffs receive a greater proportion of excitatory synapses from multiple sources including the lateral geniculate nucleus, which is not known to project to the interpuffs.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Córtex Visual/metabolismo , Ácido gama-Aminobutírico/metabolismo , Animais , Axônios/ultraestrutura , Complexo IV da Cadeia de Transporte de Elétrons/imunologia , Imuno-Histoquímica , Macaca mulatta , Microscopia Eletrônica , Neurônios/ultraestrutura , Sinapses/ultraestrutura , Ácido gama-Aminobutírico/imunologia
11.
J Comp Neurol ; 370(3): 350-66, 1996 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-8799861

RESUMO

The purpose of the present study was to examine the effects of retinal impulse blockade on gamma-aminobutyric acid (GABA)-immunoreactive (GABA-IR) neurons in cytochrome oxidase (CO)-rich puffs of the adult monkey striate cortex. Specifically, we wished to know if changes occurred in their CO activity, GABA immunoreactivity, and synaptic organization. A double-labeling technique, which combined CO histochemistry and postembedding GABA immunocytochemistry on the same ultrathin sections, was used to reveal simultaneously the distribution of the two markers. We quantitatively compared changes in GABA-IR neurons of deprived puffs (DPs) with respect to non-deprived puffs (NPs) 2 weeks after monocular tetrodotoxin treatment. We found that the proportion of darkly CO reactive mitochondria in GABA-IR neurons of DPs drastically decreased to about half of those in NPs. There was a greater reduction of CO levels in GABA-IR axon terminals than in their cell bodies and dendrites. In contrast, most non-GABA-IR neurons displayed no significant change in their CO levels. Morphologically, GABA-IR neurons and axon terminals in DPs showed a significant shrinkage in their mean size. GABA immunoreactivity, as indicated by the density of immunogold particles in GABA-IR neurons, declined in DPs, and a greater decrease was also found in axon terminals than in cell bodies or dendrites. Moreover, the numerical density of GABA-IR axon terminals and synapses in DPs was significantly reduced without changes in that of asymmetric and symmetric synapses. Thus, the present results support the following conclusions: 1) Oxidative metabolism and neurotransmitter expression in GABA-IR neurons are tightly regulated by neuronal activity in adult monkey striate cortex; 2) GABA-IR neurons are much more vulnerable to functional deprivation than non-GABA-IR ones, suggesting that these inhibitory neurons have stringent requirement for sustained excitatory input to maintain their heightened oxidative capacity; and 3) intracortical inhibition mediated by GABA transmission following afferent deprivation may be decreased in deprived puffs, because the oxidative capacity and transmitter level in GABAergic neurons, especially in their axon terminals, are dramatically reduced.


Assuntos
Macaca mulatta/fisiologia , Plasticidade Neuronal/fisiologia , Neurônios/fisiologia , Privação Sensorial/fisiologia , Córtex Visual/fisiologia , Ácido gama-Aminobutírico/análise , Animais , Compartimento Celular/fisiologia , Complexo IV da Cadeia de Transporte de Elétrons/análise , Histocitoquímica/métodos , Microscopia Eletrônica , Neurônios/química , Neurônios/ultraestrutura , Sinapses/fisiologia , Visão Monocular/fisiologia , Córtex Visual/química , Córtex Visual/citologia
12.
J Comp Neurol ; 373(1): 139-55, 1996 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-8876469

RESUMO

Cytochrome oxidase (CO), a mitochondrial energy-generating enzyme, contains both mitochondrial- and nuclear-encoded subunits. In neurons, local levels of CO activity vary among different neuronal compartments, reflecting local demands for energy. The goals of the present study were to determine if compartmental distribution of CO subunit proteins from the two genomes was correlated with local CO activity, and if their expression was regulated proportionately in neurons. The subcellular distributions of mitochondrial-encoded CO III and nuclear-encoded CO Vb proteins were quantitatively analyzed in mouse cerebellar sections subjected to postembedding immunocytochemistry. Local levels of subunit proteins were also compared to local CO activity, as revealed by CO cytochemistry. In order to study the regulation of subunit protein expression, we assessed changes in immunoreactivity of the two CO subunits as well as changes in CO activity in mouse superior colliculus after 1 to 7 days of monocular enucleation. We found that immunoreaction product for both CO III and CO Vb existed almost exclusively in mitochondria, but their compartmental distributions were different. CO III was nonhomogeneously distributed among different neuronal compartments, where its local level was positively correlated with that of CO activity. In contrast, the subcellular distribution of CO Vb was relatively uniform and did not bear a direct relationship with that of CO activity. Moreover, the two subunit proteins were disproportionately regulated by neuronal activity. CO III and CO activity exhibited parallel decreases after the deprivation of afferent input, and their changes were earlier and to a greater degree than that of CO Vb proteins. Thus, the present findings indicate that the local expression and/or distribution of CO subunit proteins from the two genomes may involve different regulatory mechanisms in neurons. Our data also suggest that the activity-dependent regulation of mitochondrial-encoded CO subunits is likely to play a major role in controlling the local levels of CO content and its activity.


Assuntos
Compartimento Celular/fisiologia , Núcleo Celular/enzimologia , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Mitocôndrias/enzimologia , Proteínas do Tecido Nervoso/metabolismo , Neurônios/enzimologia , Sequência de Aminoácidos , Animais , Especificidade de Anticorpos , Código Genético , Genoma , Histocitoquímica , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Neurônios/ultraestrutura , Colículos Superiores/citologia , Colículos Superiores/enzimologia
13.
J Comp Neurol ; 369(4): 571-90, 1996 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-8761929

RESUMO

One of the hallmarks of the primate striate cortex is the presence of cytochrome oxidase (CO)-rich puffs and CO-poor interpuffs in its supragranular layers. However, the neurochemical basis for their differences in metabolic activity and physiological properties is not well understood. The goals of the present study were to determine whether CO levels in postsynaptic neuronal compartments were correlated with the proportion of excitatory glutamate-immunoreactive (Glu-IR) synapses they received and if Glu-IR terminals and synapses in puffs differed from those in interpuffs. By combining CO histochemistry and postembedding Glu immunocytochemistry on the same ultrathin sections, the simultaneous distribution of the two markers in individual neuronal profiles was quantitatively analyzed. As a comparison, adjacent sections were identically processed for the double labeling of CO and GABA, an inhibitory neurotransmitter. In both puffs and interpuffs, most axon terminals forming asymmetric synapses (84%)--but not symmetric ones, which were GABA-IR--were intensely immunoreactive for Glu. GABA-IR neurons received mainly Glu-IR synapses on their cell bodies, and they had three times as many mitochondria darkly reactive for CO than Glu-rich neurons, which received only GABA-IR axosomatic synapses. In puffs, GABA-IR neurons received a significantly higher ratio of Glu-IR to GABA-IR axosomatic synapses and contained about twice as many darkly CO-reactive mitochondria than those in interpuffs. There were significantly more Glu-IR synapses and a higher ratio of Glu- to GABA-IR synapses in the neuropil of puffs than of interpuffs. Moreover, Glu-IR axon terminals in puffs contained approximately three times more darkly CO-reactive mitochondria than those in interpuffs, suggesting that the former may be synaptically more active. Thus, the present results are consistent with our hypothesis that the levels of oxidative metabolism in postsynaptic neurons and neuropil are positively correlated with the proportion of excitatory synapses they receive. Our findings also suggest that excitatory synaptic activity may be more prominent in puffs than in interpuffs, and that the neurochemical and synaptic differences may constitute one of the bases for physiological and functional diversities between the two regions.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Ácido Glutâmico/fisiologia , Macaca mulatta/fisiologia , Neurônios/enzimologia , Córtex Visual/fisiologia , Animais , Imuno-Histoquímica , Microscopia Eletrônica , Mitocôndrias/enzimologia , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Neurônios/ultraestrutura , Oxirredução , Terminações Pré-Sinápticas/enzimologia , Terminações Pré-Sinápticas/metabolismo , Terminações Pré-Sinápticas/ultraestrutura , Sinapses/enzimologia , Sinapses/metabolismo , Sinapses/ultraestrutura , Córtex Visual/enzimologia , Córtex Visual/ultraestrutura , Ácido gama-Aminobutírico/metabolismo
14.
J Comp Neurol ; 404(3): 310-20, 1999 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-9952350

RESUMO

Previous studies have shown that a transcription factor of the Ets family, nuclear respiratory factor 2 (NRF-2), can activate in vitro the gene expression of cytochrome oxidase (CO), a mitochondrial enzyme of oxidative metabolism. The goals of our present study were to determine whether the distribution of NRF-2 alpha subunit proteins correlated with that of CO activity in the macaque monkey visual cortex and whether the level could be perturbed by visual deprivation. We generated polyclonal antibodies specifically against human NRF-2 alpha subunit. In normal monkeys, patterns of NRF-2 alpha distribution resembled closely that of CO activity: 1) NRF-2 alpha immunoreactivity was localized in both nuclei and cytoplasm of neurons, but the levels differed among various laminae; 2) layers IVA, IVC, and VI, which had high CO activity, were labeled more densely by NRF-2 alpha than layers I, IVB, and V, which contained lower levels of both NRF-2 alpha and CO activity; and 3) CO-rich puffs in layers II and III contained a higher level of NRF-2 alpha than CO-poor interpuffs. From 1 day to 7 days after monocular impulse blockade with tetrodotoxin, there was a progressive reduction of NRF-2 alpha in deprived ocular dominance columns, in parallel with decreases in CO activity. These results suggest that local levels of NRF-2 in the monkey visual cortex closely reflect neuronal physiological and metabolic levels revealed by CO activity and that the expression of NRF-2 alpha, like that of CO, is regulated tightly by neural functional activity.


Assuntos
Proteínas de Ligação a DNA/biossíntese , Complexo IV da Cadeia de Transporte de Elétrons/biossíntese , Regulação Enzimológica da Expressão Gênica/fisiologia , Fatores de Transcrição/biossíntese , Córtex Visual/fisiologia , Sequência de Aminoácidos , Animais , Especificidade de Anticorpos , Western Blotting , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/genética , Densitometria , Complexo IV da Cadeia de Transporte de Elétrons/genética , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Fator de Transcrição de Proteínas de Ligação GA , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/genética , Imunoglobulinas/biossíntese , Imunoglobulinas/genética , Imuno-Histoquímica , Macaca mulatta , Masculino , Dados de Sequência Molecular , Neuropeptídeos/biossíntese , Neuropeptídeos/genética , Coelhos , Tetrodotoxina/farmacologia , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Córtex Visual/efeitos dos fármacos
15.
J Comp Neurol ; 417(2): 221-32, 2000 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-10660899

RESUMO

Nuclear respiratory factor 2 (NRF-2) has been shown to contribute to the transcriptional regulation of a number of subunits of respiratory chain enzymes, including cytochrome c oxidase (CO). Our recent study demonstrated a parallel distribution of the alpha subunit proteins of NRF-2 (NRF-2 alpha) with CO in the monkey striate cortex, and that it can be regulated by neuronal activity. To determine whether this regulation is at the transcriptional level, the present study examined the expression of NRF-2 alpha mRNA in normal and monocularly deprived adult monkeys. A partial NRF-2 alpha cDNA was isolated from a human brain cDNA library. Sequence analysis revealed that it shared 99% identity with the published sequence from human HeLa cells. Riboprobes of NRF-2 alpha was generated and labeled with digoxigenin-11-UTP for in situ hybridization. The expression pattern of NRF-2 alpha mRNA in the normal striate cortex paralleled that of CO activity. It was highly expressed in layers IVC and VI, which contained high levels of CO, and more densely expressed in puffs of layers II and III than in interpuffs. In monkeys monocularly treated with tetrodotoxin for 1 day to 2 weeks, both NRF-2 alpha expression and CO activity were reduced in deprived ocular dominance columns of the visual cortex and in deprived layers of the lateral geniculate nucleus. These data indicate that, in the normal and visually deprived adult monkeys, NRF-2 alpha is regulated by neuronal activity at the transcriptional level.


Assuntos
DNA Complementar/isolamento & purificação , Proteínas de Ligação a DNA/genética , Macaca fascicularis/genética , RNA Mensageiro/metabolismo , Privação Sensorial/fisiologia , Fatores de Transcrição/genética , Visão Monocular/fisiologia , Sequência de Aminoácidos , Animais , Clonagem Molecular , DNA Complementar/genética , Densitometria , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Fator de Transcrição de Proteínas de Ligação GA , Humanos , Hibridização In Situ , Macaca fascicularis/metabolismo , Dados de Sequência Molecular , RNA Mensageiro/antagonistas & inibidores , Valores de Referência , Tetrodotoxina/farmacologia , Distribuição Tecidual , Córtex Visual/metabolismo
16.
Vision Res ; 38(10): 1455-77, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9667011

RESUMO

The present study examined the relationship between an important energy-generating enzyme (cytochrome oxidase; CO), a key energy-consuming enzyme (Na+ K+ ATPase) and neurochemicals associated with excitatory glutamatergic synapses (NMDAR1 and neuronal nitric oxide synthase, nNOS) in the adult macaque retina. Polyclonal antibodies against neuronal nitric oxide synthase and N-methyl-D-aspartate receptor subunit I were generated for immunohistochemical examination and labeled sites not previously reported were found. We have also isolated cDNAs for cytochrome oxidase subunits III (mitochondrial-encoded) and IV (nuclear-encoded), as well as for a fragment of neuronal nitric oxide synthase, from a human cDNA library. The distributions of mRNAs of these genes were analyzed by in situ hybridization. We found that three or more of the markers examined coexisted in a number of sites: (a) In the inner segments of photoreceptors, high energy demand for maintaining the dark current was placed by Na+ K+ ATPase. This was partially met by ATP-generating enzymes such as CO. Neuronal NOS was also present there for the synthesis of NO and the cascading event leading to the generation of cGMP and the gating of channels for visual transduction. (b) Both the outer and inner plexiform layers had detectable amounts of all four markers, although the levels varied among them. This was most likely due to the presence of depolarizing glutamatergic synapses arising from photoreceptors and bipolar cells and such synaptic events were energy-demanding. The involvement of NMDA receptors and nNOS in these synaptic layers is strongly implicated in the present study. (c) All four markers were present in the majority of retinal ganglion cells, with some inherent heterogeneity related to intensity and size. Retinal ganglion cells are known to receive excitatory synapses from glutamatergic bipolar cells and are themselves highly active. The presence of both NMDAR1 and nNOS in these cells were verified in the present study and the energy demands related to these synaptic activities were necessarily high. Thus, active ion transporting functions related to synaptic or non-synaptically induced repolarization from the basis for an interrelationship between the neurochemicals/enzymes studied. Finally, (d) all four markers and the gene expression of CO and nNOS in the macaque retina were regulated by neuronal activity.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Óxido Nítrico Sintase/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Retina/enzimologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Tetrodotoxina/farmacologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Complexo IV da Cadeia de Transporte de Elétrons/genética , Expressão Gênica , Imuno-Histoquímica , Hibridização In Situ , Transporte de Íons , Macaca fascicularis , Macaca mulatta , Masculino , Células Fotorreceptoras/química , Retina/química , Retina/efeitos dos fármacos
17.
Zhong Yao Cai ; 23(4): 192-5, 2000 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-12575123

RESUMO

Pharmacognostical studies of Herba Artemisiae Scopariae and its adulterants were compared on morphological and microscopic characteristics. The detailed characteristics of powder microscopic identification were described.


Assuntos
Artemisia/anatomia & histologia , Plantas Medicinais/anatomia & histologia , Artemisia/citologia , Contaminação de Medicamentos , Farmacognosia , Folhas de Planta/anatomia & histologia , Folhas de Planta/citologia , Plantas Medicinais/citologia , Pós
18.
J Biomed Mater Res B Appl Biomater ; 102(2): 221-30, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23908098

RESUMO

Bulk ultrafine-grained (UFG) pure Ta had been successfully prepared by equal channel angular pressing (ECAP) technique till eight passes. The 1st, 2nd, 4th, and 8th ECAPed Ta samples were investigated in the current study, with the 0th ECAPed Ta sample as the microcrystalline counterpart control. The microstructure and grain size distribution were characterized by X-ray diffractometer patterns, scanning electron microscopy, and transmission electron microscopy analysis by means of histogram. Although the mechanical behavior of all the experimental samples were analyzed through uniaxial tensile measurement and microhardness test, in vitro biological interactions onto the substrates such as protein adsorption, cellular responses derived from different types of cell lines, and the activity of erythrocyte and platelets were further evaluated and specifically assessed by bicinchoninic acid assay, enzyme-linked immunosorbent assay, and the method of colorimetric reading. A superior percentage of protein adsorption can be observed on the substrate of the UFG 8th ECAPed Ta (around 90%), even above those on the tissue culture plate (control) and the other ECAPed Ta samples. Furthermore, the UFG 8th ECAPed Ta shows no cytotoxic within 4 days culture when incubated with the murine fibroblast cell lines (L929). In addition, a priority order in the growth of endothelial cells (ECV304) other than vascular smooth muscle cells was observed in the case of the UFG 8th ECAPed Ta. In terms of hemolysis rate and adhered platelets (both the amount and the individual morphology), an evolutionary outcome of preferentially enhanced hemocompatibility can be concluded for the case of the UFG 8th ECAPed Ta.


Assuntos
Plaquetas/metabolismo , Células Endoteliais/metabolismo , Eritrócitos/metabolismo , Teste de Materiais , Miócitos de Músculo Liso/metabolismo , Tantálio/química , Animais , Plaquetas/citologia , Linhagem Celular , Células Endoteliais/citologia , Eritrócitos/citologia , Camundongos , Miócitos de Músculo Liso/citologia , Adesividade Plaquetária , Soroalbumina Bovina/química
19.
Cell Death Dis ; 5: e1298, 2014 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-24967960

RESUMO

Recent evidence indicates that long noncoding RNAs (lncRNAs) have a critical role in the regulation of cellular processes such as differentiation, proliferation, and metastasis. These lncRNAs are dysregulated in a variety of cancers and many function as tumor suppressors; however, the regulatory factors involved in silencing lncRNA transcription are poorly understood. In this study, we showed that epigenetic silencing of lncRNA SPRY4 intronic transcript 1 (SPRY4-IT1) occurs in non-small-cell lung cancer (NSCLC) cells through direct transcriptional repression mediated by the Polycomb group protein enhancer of zeste homolog 2 (EZH2). SPRY4-IT1 is derived from an intron within SPRY4, and is upregulated in melanoma cells; knockdown of its expression leads to cell growth arrest, invasion inhibition, and elevated rates of apoptosis. Upon depletion of EZH2 by RNA interference, SPRY4-IT1 expression was restored, and transfection of SPRY4-IT1 into NSCLC cells resulted in a significant antitumoral effect, both in culture and in xenografted nude mice. Moreover, overexpression of SPRY4-IT1 was found to have a key role in the epithelial-mesenchymal transition through the regulation of E-cadherin and vimentin expression. In EZH2-knockdown cells, which characteristically showed impaired cell proliferation and metastasis, the induction of SPRY4-IT1 depletion partially rescued the oncogenic phenotype, suggesting that SPRY4-IT1 repression has an important role in EZH2 oncogenesis. Of most relevance, translation of these findings into human NSCLC tissue samples demonstrated that patients with low levels of SPRY4-IT1 expression had a shorter overall survival time, suggesting that SPRY4-IT1 could be a biomarker for poor prognosis of NSCLC.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Proliferação de Células , Epigênese Genética , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular , Neoplasias Pulmonares/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas do Tecido Nervoso , Complexo Repressor Polycomb 2/metabolismo , RNA Longo não Codificante/biossíntese , RNA Neoplásico/biossíntese , Animais , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proteína Potenciadora do Homólogo 2 de Zeste , Feminino , Humanos , Íntrons , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Nus , Metástase Neoplásica , Proteínas de Neoplasias/genética , Complexo Repressor Polycomb 2/genética , Prognóstico , RNA Longo não Codificante/genética , RNA Neoplásico/genética
20.
J Biomed Mater Res A ; 101(6): 1694-707, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23184756

RESUMO

Bulk nanocrystalline Ti bars (Grade 4, Φ4 × 3000 mm(3)) were massively fabricated by equal channel angular pressing (ECAP) via follow-up conform scheme with the microcrystalline CP Ti as raw material. Homogeneous nanostructured crystals with the average grain size of 250 nm were identified for the ECAPed Ti, with extremely high tensile/fatigue strength (around 1240/620 MPa) and adorable elongation (more than 5%). Pronounced formation of bonelike apatite for the nanocrystalline Ti group after 14 days static immersion in simulated body fluids (SBF) reveals the prospective in vitro bioactive capability of fast calcification, whereas an estimated 17% increment in protein adsorption represents good bioaffinity of nanocrystalline Ti. The documentation onto the whole life circle of osteoblast cell lines (MG63) revealed the strong interactions and superior cellular functionalization when they are co-incubated with bulk nanocrystalline Ti sample. Moreover, thread-structured specimens were designed and implanted into the tibia of Beagles dogs till 12 weeks to study the in vivo responses between bone and metallic implant made of bulk nanocrystalline Ti, with the microcrystalline Ti as control. For the implanted nanostructured Ti group, neoformed bone around the implants underwent the whole-stage transformation proceeding from originally osteons or immature woven bone to mature lamellar bone (skeletonic trabecular), even with the remodeling being finished till 12 weeks. The phenomenal osseointegration of direct implant-bone contact can be revealed from the group of the ECAPed Ti without fibrous tissue encapsulation in the gap between the implant and autogenous bone.


Assuntos
Teste de Materiais , Nanopartículas/química , Nanotecnologia/métodos , Titânio/farmacologia , Adsorção/efeitos dos fármacos , Albuminas/metabolismo , Animais , Apatitas/farmacologia , Densidade Óssea/efeitos dos fármacos , Osso e Ossos/citologia , Osso e Ossos/efeitos dos fármacos , Comunicação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Cristalização , Cães , Feminino , Humanos , Camundongos , Microscopia Eletrônica de Varredura , Modelos Biológicos , Nanopartículas/ultraestrutura , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA