RESUMO
MicroRNAs (miRNAs) are often deregulated in glioblastoma multiforme (GBM). Downregulation of microRNA-21 (miR-21), especially in GBM, is responsible for increased apoptosis, decreased cell proliferation and invasion, increased G0/G1 cell cycle arrest, and reduced chemotherapeutic resistance to doxorubicin. Furthermore, it is a critical regulator of multiple downstream genes and signaling pathways involved in gliomagenesis. Programmed cell death 4 (PDCD4) is critical in mediating apoptosis in GBM, and is downregulated by miR-21, which may mediate the resistance of glioblastoma cells against chemotherapy or radiation via its target genes PDCD4. Evidence is mounting that how alterations of these miRNAs transcription factors provide initiation, maintenance, or progression of tumors. This review will focus on the roles of miRNAs family members (particularly miR-21 and its target gene PDCD4) in tumors like glioblastoma and new targeting strategies, as examples some new targeting therapeutic methods and molecular mechanisms of signal pathways in glioblastoma therapeutics, to give the reader the current trends of approach to target regulation of these miRNA and genes for future glioma therapies.
Assuntos
Proteínas Reguladoras de Apoptose/genética , Neoplasias Encefálicas/genética , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , MicroRNAs/genética , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Ciclo Celular/genética , Linhagem Celular Tumoral , Glioblastoma/metabolismo , Glioblastoma/patologia , Glioblastoma/terapia , Humanos , MicroRNAs/metabolismo , Terapia de Alvo Molecular , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de SinaisRESUMO
In this study, the effects of gravitational settling time, temperature, speed and time of centrifugation, flocculant type and dosage, bubble size and gas amount were investigated. The results show that the simple increase in settling time and temperature is of no use for oil-water separation of the three wastewater samples. As far as oil-water separation efficiency is concerned, increasing centrifugal speed and centrifugal time is highly effective for L sample, and has a certain effect on J sample, but is not valid for S sample. The flocculants are highly effective for S and L samples, and the oil-water separation efficiency increases with an increase in the concentration of inorganic cationic flocculants. There exist critical reagent concentrations for the organic cationic and the nonionic flocculants, wherein a higher or lower concentration of flocculant would cause a decrease in the treatment efficiency. Flotation is an effective approach for oil-water separation of polymer-contained wastewater from the three oilfields. The oil-water separation efficiency can be enhanced by increasing floatation agent concentration, flotation time and gas amount, and by decreasing bubble size.
Assuntos
Óleos/isolamento & purificação , Petróleo , Polímeros/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Centrifugação , China , Floculação , Temperatura Alta , Poluição por Petróleo/prevenção & controleRESUMO
Mineral trioxide aggregate (MTA) has been shown to possess excellent sealing ability when tested with dye, bacteria, and a fluid filtration technique. Endotoxin, a component of the cell wall of Gram-negative bacteria, has been proposed to play a role in the pathogenesis of periradicular lesions. This study used a modified Limulus Amebocyte Lysate test for the presence of endotoxin as a tracer and compared the sealing ability of Super-EBA, IRM, amalgam, and MTA. The results showed that MTA permitted less endotoxin leakage than IRM and amalgam at 1, 2, 6, and 12 wk (p < 0.05), and leaked less than Super-EBA at 2 and 12 wk (p < 0.05).
