AIM:To investigate the histone modification changes of topoisomerase Ⅱα( TOPOⅡα) promoter regulatory factor Sp1 in the patients with chronic benzene poisoning .METHODS:The bone marrow samples were collect-ed from 25 chronic benzene poisoning cases and 25 controls.The chromatin immunoprecipitation assay was carried out to study the possible mechanism of TOPOⅡαpromoter regulatory factor Sp 1 expression changes .The mRNA expression of Sp1 was detected by RT-PCR.RESULTS:Compared with the controls , the histone H4 acetylation and histone H3 acetyla-tion of Sp1 in the chronic benzene poisoning patients significantly decreased (P<0.01), and histone H3K9 methylation level of Sp1 increased (P<0.01), but the histone H3K4 methylation level of SP1 was not obviously changed (P>0.05). The mRNA expression of Sp1 in the chronic benzene poisoning patients was significantly lower than that in the controls (P<0.05).CONCLUSION:In chronic benzene poisoning patients , the histone acetylation and methylation modification changes of TOPOⅡαpromoter regulatory factor Sp 1 accompanied with the changes of mRNA level are observed .Histone H4 and H3 acetylation and H3K9 methylation modification of Sp1 may play an important role in the benzene ’s hematopoiet-ic toxicities.

Objective : To study the anatomical characteristics of the root and root canal system of the mandibular second permanent molar in the Uygur people and provide a reference for clinical practice. Methods : A total of 125 mandibular second permanent molars were extracted from Uygur patients in hospitals in the Xinjiang Uygur Autonomous Region. Three-dimensional reconstruction was performed after micro-CT scanning. The number of root canals, the root canal type (Weine classification and Fan′s C-shaped canal classification) and the occurrence of lateral accessory canals were observed. Results : A sex difference was not detected in the root number or root form (χ2 = 1.277, P = 0.259). The incidence of 2-rooted molars was 70.4% (n = 88); type 2-1 canals were most common in the mesial root, with an incidence of 29.5%, followed by type 1-1 and 2-2 canals (each with an incidence of 26.1%), and the distal root mostly had a type 1-1 canal (96.6%). The incidence of single-rooted molars was 28.8%, and the frequency of C-shaped (n = 28) and non-C-shaped (n = 8) single-rooted molars was 22.4% and 6.4%, respectively. A three-rooted molar was detected in one case. The incidence of accessory canals was 65.2%. Conclusion Uygur mandibular second molars are mainly composed of two roots, and the incidence of a single root and root canal fusion is low (including C-shaped canals). Two-rooted molars frequently have two mesial canals and one distal canal.

Objective To investigate the mutations of IDH1,IDH2,p53 gene,and Ki-67 protein expression in different grade of gliomas and identify the association with its clinical relevance. Methods The mutations of IDH1,IDH2 and p53 gene were detected by direct DNA sequencing,and protein expression of Ki-67 was analyzed by immunohistochemistry. The correlations between gender,age,tumor site,differentiation degree and pathological type of patients were analyzed. Results R132H mutation of IDH1 gene was detected in 32.6% samples (14/46 cases),of which the proportion of WHO classification grade Ⅱ was 40.0%,and grade Ⅲ was 58.3%. IDH1 mutations were shown correlated with age,pathology level Ⅱ-Ⅲ,and Ki-67 low expression. p53 mutations were detected in 4 glioblastomas,with mutations located at exon 7,8. IDH1 gene mutation was negatively correlated with Ki-67 expression. Conclusions The proportion of IDH1 gene mutation in different pathological types of gliomas is different,which is the highest in gradeⅡ~Ⅲ. It is suggested that the subtypes should be listed independently by routine tests. Mutations in p53 gene are more common in primary glioblastomas and may be associated with adverse outcomes. The combined detection of DH1,p53 and Ki-67 is conducive to the diagnosis and prognosis of glioma.