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1.
Zhonghua Yi Xue Za Zhi ; 101(17): 1262-1268, 2021 May 11.
Artículo en Chino | MEDLINE | ID: mdl-34865396

RESUMEN

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.


Asunto(s)
Neoplasias de los Conductos Biliares , Colestasis , Tumor de Klatskin , Neoplasias de los Conductos Biliares/diagnóstico por imagen , Femenino , Humanos , Masculino , Estudios Retrospectivos , Ultrasonografía
2.
Neoplasma ; 67(3): 604-613, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32266816

RESUMEN

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.


Asunto(s)
Carcinoma Papilar/patología , MicroARNs/genética , Cáncer Papilar Tiroideo/patología , Neoplasias de la Tiroides/patología , Carcinoma Papilar/genética , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Humanos , Proteína Quinasa 1 Activada por Mitógenos , Invasividad Neoplásica , Receptor ErbB-4 , Cáncer Papilar Tiroideo/genética , Neoplasias de la Tiroides/genética
3.
Eur J Orthop Surg Traumatol ; 28(6): 1089-1094, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29453752

RESUMEN

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.


Asunto(s)
Artrodesis , Neuropatías del Plexo Braquial/cirugía , Articulación del Hombro/cirugía , Adulto , Artralgia , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Fuerza Muscular , Medición de Resultados Informados por el Paciente , Satisfacción del Paciente , Proyectos Piloto , Rango del Movimiento Articular , Recuperación de la Función , Estudios Retrospectivos , Resultado del Tratamiento
4.
Braz J Med Biol Res ; 49(6)2016 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-27240294

RESUMEN

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.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/metabolismo , Proliferación Celular/fisiología , MicroARNs/metabolismo , Núcleo Pulposo/metabolismo , Proteínas de Unión al ARN/metabolismo , Adulto , Anciano , Proteínas Reguladoras de la Apoptosis/análisis , Proteínas Reguladoras de la Apoptosis/genética , Western Blotting , Recuento de Células , Células Cultivadas , Femenino , Expresión Génica , Humanos , Degeneración del Disco Intervertebral/metabolismo , Luciferasas , Masculino , Metaloproteinasa 2 de la Matriz/análisis , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/análisis , Metaloproteinasa 9 de la Matriz/genética , MicroARNs/análisis , MicroARNs/genética , Persona de Mediana Edad , Núcleo Pulposo/citología , ARN Mensajero/análisis , Proteínas de Unión al ARN/análisis , Proteínas de Unión al ARN/genética , Valores de Referencia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Fracturas de la Columna Vertebral/metabolismo , Factores de Tiempo
5.
Braz. j. med. biol. res ; 49(6): e5020, 2016. tab, graf
Artículo en Inglés | LILACS | ID: biblio-951681

RESUMEN

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.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Proteínas de Unión al ARN/metabolismo , MicroARNs/metabolismo , Proliferación Celular/fisiología , Proteínas Reguladoras de la Apoptosis/metabolismo , Núcleo Pulposo/metabolismo , Valores de Referencia , Factores de Tiempo , Proteínas Reguladoras de la Apoptosis/análisis
6.
Cell Death Dis ; 5: e1298, 2014 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-24967960

RESUMEN

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.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Proliferación Celular , Epigénesis Genética , Transición Epitelial-Mesenquimal , Regulación Neoplásica de la Expresión Génica , Péptidos y Proteínas de Señalización Intracelular , Neoplasias Pulmonares/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas del Tejido Nervioso , Complejo Represivo Polycomb 2/metabolismo , ARN Largo no Codificante/biosíntesis , ARN Neoplásico/biosíntesis , Animales , Biomarcadores de Tumor/genética , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Proteína Potenciadora del Homólogo Zeste 2 , Femenino , Humanos , Intrones , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Masculino , Ratones , Ratones Desnudos , Metástasis de la Neoplasia , Proteínas de Neoplasias/genética , Complejo Represivo Polycomb 2/genética , Pronóstico , ARN Largo no Codificante/genética , ARN Neoplásico/genética
7.
J Biomed Mater Res B Appl Biomater ; 100(5): 1404-10, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22566153

RESUMEN

Conventional microcrystalline pure iron (MC-Fe) becomes a new candidate as biodegradable metals, which has the insufficient physical feature and inferior biodegradation behavior. Novel bulk nanocrystalline pure iron (NC-Fe) was fabricated via equal channel angular pressing technique in the present work to overcome these problems. The contact angle test with water and glycerol droplets shows a smaller angle (though >90°) of NC-Fe than that of MC-Fe, which implies a lower surface energy of NC-Fe. The surface roughness of NC-Fe increased greatly than that of MC-Fe. A further comparative study of corrosion and electrochemistry performance between NC-Fe and its original MC-Fe was investigated in physiological saline with different dissolved oxygen concentration, aiming to in vitro simulate the corrosion process of coronary stent occurred in physiological environment. The electrochemical impedance spectra analysis and anodic polarization measurements indicated that the NC-Fe exhibited higher corrosion resistance than that of the MC-Fe; meanwhile obvious enhanced corrosion resistance with the decrement of dissolved oxygen concentration was observed. Related equivalent circuit model and surface reconstruction process were further discussed, and the degradation mechanism of the MC-Fe and NC-Fe were finally established.


Asunto(s)
Hierro/química , Nanopartículas del Metal/química , Modelos Químicos , Oxígeno/química , Cloruro de Sodio/química , Corrosión , Electroquímica
8.
Br J Cancer ; 106(7): 1320-30, 2012 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-22453125

RESUMEN

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.


Asunto(s)
Neoplasias Colorrectales/genética , MicroARNs/fisiología , Células Madre Neoplásicas/fisiología , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Transportadoras de Casetes de Unión a ATP/genética , Diferenciación Celular , Línea Celular Tumoral , Transformación Celular Neoplásica , Neoplasias Colorrectales/patología , Regulación hacia Abajo , Resistencia a Antineoplásicos , Citometría de Flujo , Regulación Neoplásica de la Expresión Génica , Humanos , Metaloproteinasa 16 de la Matriz/genética , MicroARNs/metabolismo , Invasividad Neoplásica , Proteínas de Neoplasias/genética
9.
Dent Mater ; 27(7): 677-83, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21514955

RESUMEN

OBJECTIVES: SUS 304 stainless steels have been widely used in orthodontics and implants such as archwires, brackets, and screws. The purpose of present study was to investigate the biocompatibility of both the commercial microcrystalline biomedical 304 stainless steel (microcrystalline 304ss) and novel-fabricated nanocrystalline 304 stainless steel (nanocrystalline 304ss). METHODS: Bulk nanocrystalline 304ss sheets had been successfully prepared by microcrystalline 304ss plates using severe rolling technique. The electrochemical corrosion and ion release behavior immersion in artificial saliva were measured to evaluate the property of biocorrosion in oral environment. The cell lines of murine and human cell lines from oral and endothelial environment were co-cultured with extracts to evaluate the cytotoxicity and provide referential evidence in vivo. RESULTS: The polarization resistance trials indicated that nanocrystalline 304ss is more corrosion resistant than the microcrystalline 304ss in oral-like environment with higher corrosion potential, and the amount of toxic ions released into solution after immersion is lower than that of the microcrystalline 304ss and the daily dietary intake level. The cytotoxicity results also elucidated that nanocrystalline 304ss is biologically compatible in vitro, even better than that of microcrystalline 304ss. SIGNIFICANCE: Based on the much higher mechanical and physical performances, nanocrystalline 304ss with enhanced biocorrosion property, well-behaved in vitro cytocompatibility can be a promising alternative in orthodontics and fixation fields in oral cavity.


Asunto(s)
Aleaciones Dentales/química , Aleaciones Dentales/toxicidad , Mucosa Bucal/efectos de los fármacos , Acero Inoxidable/química , Acero Inoxidable/toxicidad , Células 3T3 , Aleaciones/química , Aleaciones/toxicidad , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Cromo/análisis , Corrosión , Cristalización , Análisis del Estrés Dental , Técnicas Electroquímicas , Células Endoteliales/efectos de los fármacos , Humanos , Células L , Ensayo de Materiales , Nanopartículas del Metal/química , Nanopartículas del Metal/toxicidad , Ratones , Mucosa Bucal/citología , Níquel/análisis , Saliva Artificial , Resistencia a la Tracción
10.
Biomed Mater ; 5(6): 065015, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21079282

RESUMEN

Bulk nanocrystalline pure iron rods were fabricated by the equal channel angular pressure (ECAP) technique up to eight passes. The microstructure and grain size distribution, natural immersion and electrochemical corrosion in simulated body fluid, cellular responses and hemocompatibility were investigated in this study. The results indicate that nanocrystalline pure iron after severe plastic deformation (SPD) would sustain durable span duration and exhibit much stronger corrosion resistance than that of the microcrystalline pure iron. The interaction of different cell lines reveals that the nanocrystalline pure iron stimulates better proliferation of fibroblast cells and preferable promotion of endothelialization, while inhibits effectively the viability of vascular smooth muscle cells (VSMCs). The burst of red cells and adhesion of the platelets were also substantially suppressed on contact with the nanocrystalline pure iron in blood circulation. A clear size-dependent behavior from the grain nature deduced by the gradual refinement microstructures was given and well-behaved in vitro biocompatibility of nanocrystalline pure iron was concluded.


Asunto(s)
Células Sanguíneas/efectos de los fármacos , Hierro/química , Hierro/farmacología , Nanoestructuras/administración & dosificación , Nanoestructuras/química , Animales , Materiales Biocompatibles/síntesis química , Materiales Biocompatibles/farmacología , Células Sanguíneas/fisiología , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Corrosión , Cristalización/métodos , Humanos , Ensayo de Materiales , Ratones , Nanoestructuras/ultraestructura , Tamaño de la Partícula
11.
Ann Plast Surg ; 65(4): 430-6, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20798625

RESUMEN

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.


Asunto(s)
Cartílago Articular/cirugía , Condrocitos/trasplante , Ingeniería de Tejidos/métodos , Andamios del Tejido , Análisis de Varianza , Animales , Materiales Biocompatibles , Cartílago/citología , Cartílago/trasplante , Cartílago Articular/fisiopatología , Condrocitos/citología , Modelos Animales de Enfermedad , Rechazo de Injerto , Supervivencia de Injerto , Regeneración Tisular Dirigida , Articulación de la Rodilla , Distribución Aleatoria , Valores de Referencia , Sensibilidad y Especificidad , Sus scrofa , Porcinos , Recolección de Tejidos y Órganos , Trasplante Homólogo
12.
Vision Res ; 38(10): 1455-77, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9667011

RESUMEN

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.


Asunto(s)
Complejo IV de Transporte de Electrones/metabolismo , Óxido Nítrico Sintasa/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Retina/enzimología , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Tetrodotoxina/farmacología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Complejo IV de Transporte de Electrones/genética , Expresión Génica , Inmunohistoquímica , Hibridación in Situ , Transporte Iónico , Macaca fascicularis , Macaca mulatta , Masculino , Células Fotorreceptoras/química , Retina/química , Retina/efectos de los fármacos
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