ABSTRACT
The massive loss of oligodendrocytes caused by various pathological factors is a basic feature of many demyelinating diseases of the central nervous system (CNS). Based on a variety of studies, it is now well established that impairment of oligodendrocyte precursor cells (OPCs) to differentiate and remyelinate axons is a vital event in the failed treatment of demyelinating diseases. Recent evidence suggests that Foxg1 is essential for the proliferation of certain precursors and inhibits premature neurogenesis during brain development. To date, very little attention has been paid to the role of Foxg1 in the proliferation and differentiation of OPCs in demyelinating diseases of the CNS. Here, for the first time, we examined the effects of Foxg1 on demyelination and remyelination in the brain using a cuprizone (CPZ)-induced mouse model. In this work, 7-week-old Foxg1 conditional knockout and wild-type (WT) mice were fed a diet containing 0.2% CPZ w/w for 5 weeks, after which CPZ was withdrawn to enable remyelination. Our results demonstrated that, compared with WT mice, Foxg1-knockout mice exhibited not only alleviated demyelination but also accelerated remyelination of the demyelinated corpus callosum. Furthermore, we found that Foxg1 knockout decreased the proliferation of OPCs and accelerated their differentiation into mature oligodendrocytes both in vivo and in vitro. Wnt signaling plays a critical role in development and in a variety of diseases. GSK-3β, a key regulatory kinase in the Wnt pathway, regulates the ability of β-catenin to enter nuclei, where it activates the expression of Wnt target genes. We then used SB216763, a selective inhibitor of GSK-3β activity, to further demonstrate the regulatory mechanism by which Foxg1 affects OPCs in vitro. The results showed that SB216763 clearly inhibited the expression of GSK-3β, which abolished the effect of the proliferation and differentiation of OPCs caused by the knockdown of Foxg1. These results suggest that Foxg1 is involved in the proliferation and differentiation of OPCs through the Wnt signaling pathway. The present experimental results are some of the first to suggest that Foxg1 is a new therapeutic target for the treatment of demyelinating diseases of the CNS.
ABSTRACT
Objective To study the clinicoradiologic significance of C sign.Methods 773 cases of standard ankle CR radiographs were presented for diagnosis of acute trauma and ankle pain. There were 565 males and 208 females, ages ranged from 10 to 81. There were 630 cases of acute trauma and 143 cases of painful ankle. C sign incidence, C sign figuration, distance of the medial facet of talocalcaneal joint, and the figuration of sustentaculum tali were studied. The relationship between C sign and talocalcaneal coalition was analysed.Results The incidence of C sign was 54.6%(422/773). The female incidence was 61.1%(127/208) ,which was more than that of male(52.2%,295/565)(P
ABSTRACT
Objective To study the incidence and radiologic findings of calcaneonavicular coalition.Methods CR films of foot andankle in 1361 cases were presented,which were evaluated for acute trauma or chronic pain.There were 588 cases of foot CR and 773 cases of ankle CR,age ranged from 10 years to 91 years(984 cases of 20~40 years).The prevalence of calcaneonavicular coalition was determined and the different significance of both male and female,acute trauma and chronic pain group were analysed.Results In 1361 cases,72 cases of calcaneonavicular coalition(5.3%) were demonstrated,8.7%(47/588)on foot CR films and 3.2%(25/773) on ankle CR films.Calcaneonavicular coalition was more dipicted on foot CR films than on ankle CR films(P0.05).Conclusion The foot CR films is more superexcellent than the ankle CR films on demonstrating calcaneonavicular coalition.
ABSTRACT
20 years)was 8.60%(48/558) , which was more than that in the second decade of life ( 5.22% ). The incidence of painful group was 9.79%(14/143),which was more than that in foot trauma group 6.78%(40/630).The positive C sign was presented in 61.1%(33/54),posterior-type coalition in 38.9%(21/54),short talar neck sign in 61.1%(33/54)and talar beak sign in 22.2%(12/54). Conclusion The talocalcaneal coalition is a common development abnormality in our country. We must pay attention to the diagnosis of talocalcaneal coalition for painful foot adulthood.