Myostatin inhibits proliferation but not differentiation of trout myoblasts

The muscle growth in mammals is regulated by several growth factors including myostatin (MSTN), a member of the transforming growth factor-beta (TGF-beta) superfamily. To date, it is unknown in fish whether MSTN could have any effect on proliferation or differentiation of myogenic cells. Using culture of trout satellite cells, we showed that mstn1a and mstn1b mRNA are expressed in myoblasts and that their expression decreased in differentiating myoblasts. We also demonstrated that a treatment with huMSTN decreased the proliferation of IGF1-stimulated myoblasts in a dose-dependent manner. By contrast, treatment of myoblasts with 100 nM of huMSTN for three days, did not affect the percentage of positive cells for myogenin neither the percentage of nuclei in myosin positive cells. Moreover, our results clearly indicated that huMSTN treatment had no effect on MyoD and myogenin protein levels, which suggests that huMSTN did not strongly affect MyoD activity. In conclusion, we showed that huMSTN inhibited proliferation but not differentiation of trout myoblasts, probably resulting from a lack of huMSTN effect on MyoD activity. Altogether, these results show high interspecies differences in the function of MSTN.     

Effects of growth on maxillary distraction osteogenesis in cleft lip and palate

PurposeThe objective was to analyze the effects of growth on the long-term result of maxillary distraction osteogenesis (DO) in cleft lip and palate (CLP).Patients and methodsRetrospective study of 24 CLP cases with long-term follow-up operated for maxillary DO using the Polley and Figueroa technique: 10 patients were distracted during growth, while 14 patients were operated after their growth spurt. Preoperative (T0), 6–12 months postoperative (T1), and ≥4 years postoperative (T2) cephalometric radiographs were evaluated. A classical cephalometric analysis was used to assess the treatment stability, and a Procrustes superimposition method was performed to assess local changes in the maxilla and the mandible.ResultsAt T0, the mean age was of 11.9 ± 1.4 years for growing patient, and 17.9 ± 3.5 years for patient treated after their growth spurt (P < 0.001). Between T0 and T1, a greater increase of the SNA was shown in growing patients (P = 0.036), but the relapse was more important between T1 and T2, with a significant decrease of the SNA (P = 0.002) and ANB (P = 0.032) compared to the patients treated after their growth spurt. Although not significant, growing patients showed greater rotations of their palatal plane and mandibular plane.ConclusionsMaxillary DO in CLP does not correct the growth deficit inherent to the pathology. Overcorrection of at least 20% is advised during growth.     

Medical treatment for sphincter of oddi dysfunction:Can it replace endoscopic sphincterotomy?

AIM:To report the results of a medical management of sphincter of oddi dysfunction(SOD) after an intermediate follow-up period.METHODS:A total of 59 patients with SOD(2 men and 57 women,mean age 51 years old) were included in this prospective study.After medical treatment for one year,the patients were clinically re-evaluated after an average period of 30 mo.RESULTS:The distribution of the patients according to the Milwaukee's classification was the following:11 patients were type 1,34 were type 2 and 14 were type 3.Fourteen patients underwent an endoscopic sphincterotomy(ES) after one year of medical treatment.The median intermediate follow-up period was 29.8 ± 3 mo(3-72 mo).The initial effectiveness of the medical treatment was complete,partial and poor among 50.8%,13.5% and 35%,respectively,of the patients.At the end of the follow-up period,37 patients(62.7%) showed more than 50% improvement.The rate of improvement in patients who required ES was not significantly different compared with the patients treated conservatively(64.2% vs 62.2%,respectively).CONCLUSION:Our study confirms that conservative medical treatment could be an alternative to endoscopic sphincterotomy because,after an intermediate follow-up period,the two treatments show the same success rates.     

Dilatations géantes des espaces de Virchow-Robin symptomatiques

Introduction

Perivascular spaces, known as Virchow-Robin spaces (VRS), may become massively enlarged but are usually an incidental finding. However, a few reports on patients with unusually large VRS have mentioned association with neurological symptoms. We report a series of three symptomatic patients with extremely wide Virchow-Robin spaces documented on brain magnetic resonance imaging (MRI).

Methods

We retrospectively analyzed the medical records and brain MRI of three symptomatic patients, who had been diagnosed with VRS widening.

Case reports

In all three patients, the unusual widening of the VRS was located within the subcortical white matter with asymmetric distribution. Their neurological symptoms were epilepsy and neurological deficits which correlated well with the lesions seen on the MRI. Two patients had associated white matter hyperintensities: in the first case associated gliosis and in the second case, with vascular leukoencephalopathy.

Conclusions

Enlarged symptomatic VRS are rare. The underlying pathophysiological mechanisms remain uncertain. We report three cases with symptomatic giant dilatation of the Virchow-Robin spaces.