Objectives:To analyze the clinical efficacy of Cheneau brace in adolescent idiopathic scoliosis(AIS)patients and to discuss the changes of curve type during the treatment.Methods:75 patients with AIS treated with Cheneau brace from October 2016 to November 2021 were included.There were 69 females and 6 males,averaged 11.9±1.0 years old when starting to wear the brace,with a mean initial main curve Cobb angle of 29.8°±8.5° and an initial Risser's sign ≤2.Clinical and imaging data were collected,including age,gender,menarche age,time of daily wear,and full-length radiographs of the spine before initial treatment and at the final follow-up.All the patients were followed up for 1 year after finishing brace treatment.The curve types of the patients were counted using the main curve type and the modified Lenke classification system(mLenke),and changes in curve types and the efficacy of bracing in patients with different curve types were analyzed.Results:After 25.7±10.8 months of brace treatment,the patients averaged 14.2±1.2 years old when finishing brace treatment,and the mean main Cobb angle was 27.6°±12.0°.Among the patients,scoliosis was controlled in 63 while progressed in 12,and 23 patients were treated surgically.The rates of success of brace and control of curve were higher in patients with main lumbar curve than those in patients with main thoracic curve(P=0.043,P=0.003).There was a difference in the rate of brace success and control of curve in patients with each mLenke classification(P＜0.001,P=0.005).The highest rates of brace success and control of curve were found in patients of mLenke type Ⅴ,while mLenke type Ⅳ patients had the lowest success rate of brace treatment success and mLenke type Ⅱ patients had the lowest rate of control of curve.Before and after brace treatment,there was a difference in the proportion of patients with each main curve type(P=0.019),and the proportion of patients with each mLenke classification had no statistical difference(P=0.071).There were differences in the rate of change of curve type in each main curve type and each mLenke classification both(P＜0.001,P=0.020).No significant differences were seen in the rates of success of brace treatment and control of curve between patients with and without change in curve type under the two curve type classifications.Conclusions:The efficacy of Cheneau brace varies among AIS patients with different curve types.Patients with a main thoracic curve tend to have a poor response to bracing compared with patients of main lumbar curve;During the treatment with Cheneau brace,the patient's curve types may change,and the overall trend of curve type change is upward shifting of the main curve.The rate and outcome of curve type changes vary among patients with different curve types,and curve type changes may also occur in curve controlled or corrected patients.

Deacetylation of chitin is closely related to insect development and metamorphosis. Chitin deacetylase (CDA) is a key enzyme in the process. However, to date, the CDAs of Bombyx mori (BmCDAs), which is a model Lepidopteran insect, were not well studied. In order to better understand the role of BmCDAs in the metamorphosis and development of silkworm, the BmCDA2 which is highly expressed in epidermis was selected to study by bioinformatics methods, protein expression purification and immunofluorescence localization. The results showed that the two mRNA splicing forms of BmCDA2, namely BmCDA2a and BmCDA2b, were highly expressed in the larval and pupal epidermis, respectively. Both genes had chitin deacetylase catalytic domain, chitin binding domain and low density lipoprotein receptor domain. Western blot showed that the BmCDA2 protein was mainly expressed in the epidermis. Moreover, fluorescence immunolocalization showed that BmCDA2 protein gradually increased and accumulated with the formation of larval new epidermis, suggesting that BmCDA2 may be involved in the formation or assembly of larval new epidermis. The results increased our understandings to the biological functions of BmCDAs, and may facilitate the CDA study of other insects.
Animals ; Bombyx/metabolism* ; Metamorphosis, Biological/genetics* ; Larva/metabolism* ; Gene Expression ; Insect Proteins/metabolism* ; Chitin