No abstract

The objective of this study was to explore the mechanism underlying osteoblast suppression in the process of hematopoietic stem cells mobilization induced by granulocyte colony‐stimulating factor (G‐CSF). The apoptosis of human and mouse osteoblasts was examined by detecting caspase 3. The levels of serum DKK1 and osteocalcin in the supernatant of co‐culture of mouse osteoblasts and mouse bone marrow nucleated cells were measured. The number of mouse osteoblasts co‐cultured with mouse bone marrow nucleated cells was measured and the osteocalcin mRNA level was also measured. The G‐CSF‐induced decrease in osteoblast function was partly due to the apoptosis of osteoblasts. There was no significant difference in the level of serum DKK1 in healthy donors before and 5 days after mobilization. The osteocalcin gene and protein expression was significantly different in co‐cultured osteoblasts with bone marrow nucleated cells treated with and without G‐CSF. Osteoblasts undergo apoptosis during mobilization and G‐CSF affects osteoblasts through bone marrow nucleated cells.

Diagnostic was suspected on hypotonia with poor suck in the neonatal period in the first case, hypotonia with history of feeding difficulty and psychomotor developmental delay in the second case and hyperphagia with obesity in the third case.Physical exam showed facial dysmorphy in 1 case, bilateral cryptorchidism in the 3 cases and obesity (BMI = 34.3) in the third case.Chromosome analysis with fluorescence in situ hybridization (FISH) confirmed the diagnosis with identification of the deletion 15q11.2 -q13 in the three cases.The average retreat was 2 years; the evolution was marked by morbid obesity (BMI=57) with hypertension and psychiatric disturbance with hyperactivity in the third case and significant weight gain at the age of 10 months in the second case. Conclusion Prader Willi must be suspected in all newborns with unexplained persistent hypotonia and confirmed by chromosome analysis. Early diagnosis is important to effective long-term management.