RESUMEN
Inappropriate c-MET signaling in cancer can enhance tumor cell proliferation, survival, motility, and invasion. Inhibition of c-MET signaling induces apoptosis in a variety of cancers. It has also been recognized as a novel anticancer therapy approach. Furthermore, reports have also indicated that constitutive expression of P-glycoprotein (ABCB1) is involved in the HGF/c-MET-related pathway of multidrug resistance ABCB1-positive human hepatocellular carcinoma cell lines. We previously reported that elevated expression levels of PKCδ and AP-1 downstream genes, and HGF receptor (c-MET) and ABCB1, in the drug-resistant MES-SA/Dx5 cells. Moreover, leukemia cell lines overexpressing ABCB1 have also been shown to be more resistant to the tyrosine kinase inhibitor imatinib mesylate. These findings suggest that chemoresistant cancer cells may also develop a similar mechanism against chemotherapy agents. To circumvent clinical complications arising from drug resistance during cancer therapy, the present study was designed to investigate apoptosis induction in ABCB1-overexpressed cancer cells using c-MET-targeted RNA interference technology in vitro and in vivo. The results showed that cell viability decreased and apoptosis rate increased in c-MET shRNA-transfected HGF/c-MET pathway-positive MES-SA/Dx5 and MCF-7/ADR2 cell lines in a dose-dependent manner. In vivo reduction of tumor volume in mice harboring c-MET shRNA-knockdown MES-SA/Dx5 cells was clearly demonstrated. Our study demonstrated that downregulation of c-MET by shRNA-induced apoptosis in a multidrug resistance cell line.
Asunto(s)
Proteínas Proto-Oncogénicas c-met/genética , Subfamilia B de Transportador de Casetes de Unión a ATP/biosíntesis , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Animales , Apoptosis/genética , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Doxorrubicina/farmacología , Resistencia a Múltiples Medicamentos , Femenino , Técnicas de Silenciamiento del Gen , Xenoinjertos , Humanos , Células MCF-7 , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Proteínas Proto-Oncogénicas c-met/deficiencia , Proteínas Proto-Oncogénicas c-met/metabolismo , Sarcoma/tratamiento farmacológico , Sarcoma/genética , Sarcoma/metabolismo , Sarcoma/patología , Transfección , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
AIMS: To establish whether the structural parameters provided by the Heidelberg retina tomograph (HRT) and the laser diagnostics glaucoma scanning system (GDx) can be used to reflect functional damage in the visual field. METHODS: 62 patients with primary open angle glaucoma underwent examination with the HRT, GDx, and Humphrey field analyser. The relations between the topographic parameters, retinal nerve fibre parameters, and visual field indices were analysed by scatter plot and linear regression. RESULTS: Among the topographic parameters generated by the HRT, rim area had the best correlation with visual field indices. The "number," maximum modulation, and ellipse modulation generated by the GDx also had correlations with visual field indices. The correlations were better for the sectoral parameters than the global parameters. However, great interindividual variation was found in the association. CONCLUSION: Although relations were found between some topographic parameters, RNFL parameters, and visual field indices, great interindividual variation limits the prediction of one parameter from the other. Therefore, both structural and functional aspects should be evaluated in order to obtain full characterisation of the glaucomatous damage for clinical judgment and treatment.
Asunto(s)
Glaucoma de Ángulo Abierto/patología , Disco Óptico/patología , Enfermedades del Nervio Óptico/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Glaucoma de Ángulo Abierto/fisiopatología , Humanos , Rayos Láser , Masculino , Microscopía Confocal/métodos , Persona de Mediana Edad , Oftalmoscopía , Enfermedades del Nervio Óptico/fisiopatología , Tomografía/métodos , Campos Visuales/fisiologíaRESUMEN
The bioleaching mechanism of pyrite by the indigenous Thiobacillus thiooxidans was examined with the aid of scanning electron microscopy (SEM) and atomic force microscopy (AFM) images of the pyrite surface. The presence of pyrite eliminated the lag phase during growth of this microorganism. This was due to the stimulatory effect on cell growth of the slight amount of Cu2+ that had leached from the pyrite. Zn2+ was found to be much more readily solubilized than Cu2+. The efficiency of bioleaching was four times higher than that of chemical leaching. SEM images provided evidence of direct cell attachment onto the pyrite surface, thereby enhancing the bioleaching rate. Furthermore, extracellular polymeric substances (EPSs) were found on the pyrite surface after 4 days of oxidation. AFM images showed that the pyrite surface area positively correlated with the oxidation rate. A combination of direct and indirect mechanism is probably responsible for the oxidation of pyrite by T. thiooxidans.
Asunto(s)
Acidithiobacillus thiooxidans/metabolismo , Hierro/metabolismo , Sulfuros/metabolismo , Hierro/química , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Oxidación-Reducción , Sulfuros/químicaRESUMEN
By means of X ray photography tests were made of 224 (100 males and 124 females) volunteer Chinese adults of han nationality to study the related regular patterns of superimposed projection of face landmarks onto the skull. On the basis of these tests, the present article reveals from a forensic antropology angle the related regular patterns of plane projection of the human face with its skull. Study shows that there exist a strict individual identity and exclusiveness in relation between the human face and skull (AU)
Asunto(s)
Medicina Legal , Sistemas de Identificación de Pacientes , Antropología Física , Métodos , FotograbarRESUMEN
By means of X-ray photography tests were made of 224 (100 males and 124 females) volunteer Chinese adults of Han nationality to study the related regular patterns of superimposed projection of face landmarks onto the skull. On the basis of these tests, the present article reveals from a forensic anthropology angle the related regular patterns of plane projection of the human face with its skull. Study shows that there exist a strict individual identity and exclusiveness in relation between the human face and skull. The related regularity of displacement of face landmarks appears in projection of the skull with the human head at different photographic positions and angles. On the basis of this discovery, 52 indexes in 4 groups were established as a standard for judging the identification of a skull's body origin by means of skull-image superimposition. Based on forensic anthropology, the technique has raised to a great extent the credibility of unknown skull identification. In the past 8 years, 89 unknown skulls have been identified with their body origins which provided important and accurate evidence for the solution of murders with dismembered bodies, skeletonized bodies, and unidentified dead bodies.