Résumé
BACKGROUND:Upregulation of hedgehog protein signaling can increase the expression of osteoarthritis markers,Runx2,a disintegrin and metalloproteinase with thrombospondin motifs,collagen type X alpha 1,and matrix metalloproteinase 13,while inhibition of hedgehog proteins attenuates the severity of osteoarthritis.It is speculated that osteoarthritic chondrocytes can influence bone formation by affecting osteoblasts through the Indian hedgehog protein(IHH)signaling pathway. OBJECTIVE:To investigate the effect of human osteoarthritic chondrocytes on subchondral osteoblasts. METHODS:Tibial plateau specimens from patients with osteoarthritis were collected.Chondrocytes were extracted using enzymatic digestion,and osteoblasts were extracted using enzymatic pre-digestion + bone block method.Chondrocytes were identified by toluidine blue staining and immunofluorescence and osteoblasts were identified by alkaline phosphatase staining and immunofluorescence.Chondrocytes were cultured in sodium alginate beads to maintain chondrocyte phenotype and co-cultured with osteoblasts.The co-culture system was added with IHH signaling pathway inhibitor(cyclopamine,10 nmol/L)and activator(purmorphamine,10 nmol/L)separately.After 48 hours of co-culture,osteoblasts from each group were collected,mRNA expressions of Gli1,osteoprotegerin,Runx2,parathyroid hormone-related peptide,alkaline phosphatase,receptor activator of nuclear factor-kB ligand(RANKL)and osteocalcin were detected by qRT-PCR,and protein expressions of GLi1,oseoprotegerin and RANKL in osteoblasts were detected by western blot. RESULTS AND CONCLUSION:The mRNA expression levels of GLi1,osteoprotegerin and RUNX2 in osteoblasts were significantly increased,while the mRNA expression levels of parathyroid hormone-related peptide were decreased(P＜0.05)when co-cultured with human osteoarthritic chondrocytes.The mRNA and protein levels of Gli1 were significantly decreased after the addition of IHH signaling pathway inhibitor(cyclopamine)(P＜0.05),and the mRNA and protein levels of Gli1 were significantly increased after the addition of IHH signaling pathway activator(purmorphamine)(P＜0.05).Osteoprotegerin showed the same trend as Gli1 in the experiment.The osteoprotegerin/RANKL ratio followed the same trend as osteoprotegerin.To conclude,human osteoarthritic chondrocytes can promote the expression of Gli1,osteoprotegerin,Runx2 and other proteins in osteoblasts.The upregulation of osteoprotegerin is related to the IHH signaling pathway.Osteoarthritic chondrocytes can up-regulate the expression of osteoprotegerin in osteoblasts through the IHH signaling pathway and thus up-regulate the osteoprotegerin/RANKL ratio,which will contribute to bone formation in subchondral bone.
Résumé
Objective: To evaluate the diagnostic performance of conventional ultrasound, compression elastography (CE) and acoustic radiation force impulse imaging (ARFI) in diff erential diagnosis of benign and malignant breast tumors. Methods: A total of 98 patients with liver lesions were included in the study. The images of conventional ultrasound, CE and the values of virtual touch tissue quantiifcation (VTQ) of breast lesions were obtained. hTe diagnostic performance of conventional ultrasound, CE and ARFI were assessed by using pathology as the gold standard, and then evaluate the diagnosis effciency of these three approaches in differential diagnosing benign and malignant breast tumors. Results: The specificity, sensitivity and accuracy in the diagnosis of malignant breast tumors for conventional ultrasound were 80.0%, 81.1% and 81.7%, respectively, whereas for CE elastic score were 85.7%, 86.7% and 86.3%, respectively. With a cutoff value of 3.71 for the SR, the sensitivity, speciifcity, accuracy in diagnosis of malignant breast tumors were 97.1%, 83.3% and 88.4%, respectively. With a cutoff value of 3.78 m/s for VTQ, the sensitivity, speciifcity, accuracy in diagnosis of malignant breast tumors were 94.3%, 91.7% and 92.6%, respectively. The difference in diagnosis efficiency among ARFI, CE and conventional ultrasound in differential diagnosis of benign and malignant breast tumors was signiifcant (P<0.05). Conclusion: Conventional ultrasound, CE and ARFI are all useful for the differential diagnosis of benign and malignant breast tumors. But the diagnosis effciency of ARFI is superior to CE and conventional ultrasound. The three approaches can help each other in differential diagnosis of benign and malignant breast tumors.
Résumé
The means of survival of genomic dsRNA of reoviruses from dsRNA-triggered and Dicer-initiated RNAi pathway remains to be defined.The present study aimed to investigate the effect of Grass carp reovirus (GCRV) replication on the RNAi pathway of grass carp kidney cells (CIK).The dsRNA-triggered RNAi pathway was demonstrated unimpaired in CIK cells through RNAi assay.GCRV-specific siRNA was generated in CIK cells transfected with purified GCRV genomic dsRNA in Northern blot analysis; while in GCRV-infected CIK cells,no GCRV-specific siRNA could be detected.Infection and transfection experiments further indicated that replication of GCRV correlated with the increased transcription level of the Dicer gene and functional inhibition of in vitro synthesized egfp-siRNA in silencing the EGFP reporter gene.These data demonstrated that although only the genomic dsRNA of GCRV was sensitive to the cellular RNAi pathway,unidentified RNAi suppressor protein(s) might contribute to the survival of the viral genome and efficient viral replication.