Objective:To investigate the clinical efficacy of robot-assisted minimally invasive sacroiliac screw fixation combined with LC-II external fixation in the treatment of pelvic fracture.Methods:A retrospective analysis was conducted on 28 cases with pelvic fractures treated with robot-assisted minimally invasive sacroiliac screw fixation combined with LC-II external fixation from May 2018 to November 2022. There were 19 males and 9 females, with an average age of 43.4±16.9 years (range, 14-74 years). There was 1 case of B1 type, 1 case of B2 type, 4 cases of B3 type, 10 cases of C1 type, 9 cases of C2 type and 3 cases of C3 type by Tile classification. All the cases were treated with closed reduction, LC-II external fixation for the anterior lesions and robot-assisted minimally invasive sacroiliac screw fixation for the posterior lesions. The operation time, fluoroscopy time and excellent rate of screw placement were recorded. The quality of fracture reduction was evaluated by Matta's criteria, and the clinical effect was evaluated by Majeed score.Results:All the 28 cases successfully underwent the surgery. In 11 cases the fractures were reduced by the pelvic unlocking closed reduction device while in the other 17 cases manual reduction was applied. In this cohort, 43 screws were implanted. All the screw positions reached level I by Gras grading. The average fluoroscopy time was 16.3±5.2 s (range, 9-31 s) per screw. The average operation time was 154.9±54.7 min (range, 55-226 min). According to the Matta's criteria, the reduction was rated as excellent in 19 cases, good in 7 cases, fair in 2 cases, yielding an excellent or good rate of 93% (26/28). No iatrogenic neurovascular injury was found in all the 28 patients. The average follow-up was 18.3±7.3 months (range, 4-31 months). The fractures healed at 3.6±1.1 months (range, 2-6 months) after the surgeries. At the final follow-up, the results of the Majeed scores were rated as excellent in 13 cases, good in 11 cases, fair in 3 cases and poor in 1 case, with an excellent or good rate of 86% (24/28).Conclusion:The technique of robot-assisted minimally invasive sacroiliac screw fixation combined with LC-II external fixation used in the treatment of pelvic fracture showed good clinical results.

Objective:Explore the expression pattern of transcription factor activator protein 2C (TFAP2C) and identify the roles of Tfap2c during tooth development.Methods:Real-time fluorescence quantitative PCR (RT-qPCR) was used to analyze the relative expression level of Tfap2c in various organs of embryonic day(E)14.5 mouse embryos and mouse molar germs at E12.5-E18.5 and postnatal day (P)0-P7. The expression position of Tfap2c in mouse molar germs was demonstrated by frozen section immunofluorescence staining. Cultured mandibular molar germs were transfected with control small interfering RNA (siRNA) or Tfap2c siRNA to evaluate the effect of Tfap2c on tooth molar germs development, and RT-qPCR was used to detect the relative expression level of genes related to odontoblast expression. Dental mesenchymal cells were isolated from E14.5 molar germs and transfected with control siRNA or Tfap2c siRNA, cell counting kit 8 (CCK-8) and scratch healing test were applied to detect dental mesenchymal cell viability and migration.Results:Tfap2c was highly expressed in the early development period of mouse molar germs. Tfap2c was expressed in the epithelial and mesenchymal tissues of E13.5 mouse molar germs and there was no significant difference of relative expression of Tfap2c between them ( t=1.06, P=0.472). Tfap2c was expressed in mesenchymal tissues of E14.5 mouse molar germs and the relative expression of Tfap2c in mesenchymal tissues was significantly higher than epithelial tissues ( t=37.29, P<0.0001). For molar germs transfected with Tfap2c siRNA, the relative height of cusps (0.708±0.171) and the ratio of cusp height and crown height (0.321±0.068) was significantly lower than control group (1.000±0.287 and 0.483±0.166) ( t=2.79, P=0.012; t=2.85, P=0.015). But there was no significant difference in relative height (1.078±0.206, 0.993±0.254, t=0.83, P=0.419)and relative width (1.000±0.116, 0.999±0.122, t=0.01, P=0.992) of crowns between two groups. The relative expression level of genes related to odontoblast expression was decreased (Dspp: t=15.33, P<0.001; Dmp1: t=13.81, P<0.001). Tfap2c siRNA hinders cell migration in dental mesenchymal cells ( t=29.86, P=0.001), but there was no significant difference in CCK-8 absorbance value between two groups. The relative expression level of genes related to odontoblast expression was also decreased in dental mesenchymal cells transfected with Tfap2c siRNA (Dspp: t=3.86, P=0.031; Dmp1; t=4.36, P=0.022). Conclusions:Tfap2c highly expressed in the early morphogenesis period of mouse molar germs, mainly in mesenchymal tissues. Tfap2c affected the cusps formation of mouse molar germs and migration of dental mesenchymal cells.

ObjectiveTo conduct the sequencing and preliminarily analysis of the whole genome of BCG Shanghai D₂PB302 strain （hereinafter referred to as BCG Shanghai D₂ strain）， which has been used exclusively for the vaccine production in China. MethodsThe DNA of of BCG Shanghai D₂ strain （D2-JIA12-1） was extracted， and the whole genome was sequenced by Pacbio-RS Ⅱ. The sequence data was assembled by Smrtlink and polished with the illumina data. Genes， tRNA and rRNA were predicted based on the sequence data. The functional annotation of predicted genes was performed through BLASTP. The IVE-TB antigen gene and MTBVAC were selected as the target sequences to be compared with Mycobacterium tuberculosis H37Rv （NC_000962.3）. ResultsThe sequence length of BCG Shanghai D₂ strain was 4 045 232 bp， and the GC content was 65.66%. A total of 4 259 protein-encoding genes were predicted， with an average gene size of 933 bp. 2 476 genes had biological functions and others were hypothetical proteins.144 virulence genes were obtained by comparing with the VFDB. There were 29 type Ⅶ secretion system genes and 10 PE/PPE protein family genes. ConclusionThe whole genome sequence of BCG Shanghai D₂ strain is clarified. It lays a broad foundation for subsequent detection of the stability of major antigen genes.

To unravel the genetic mechanisms of disease and physiological traits, it requires comprehensive sequencing analysis of large sample size in Chinese populations. Here, we report the primary results of the Chinese Academy of Sciences Precision Medicine Initiative (CASPMI) project launched by the Chinese Academy of Sciences, including the de novo assembly of a northern Han reference genome (NH1.0) and whole genome analyses of 597 healthy people coming from most areas in China. Given the two existing reference genomes for Han Chinese (YH and HX1) were both from the south, we constructed NH1.0, a new reference genome from a northern individual, by combining the sequencing strategies of PacBio, 10× Genomics, and Bionano mapping. Using this integrated approach, we obtained an N50 scaffold size of 46.63 Mb for the NH1.0 genome and performed a comparative genome analysis of NH1.0 with YH and HX1. In order to generate a genomic variation map of Chinese populations, we performed the whole-genome sequencing of 597 participants and identified 24.85 million (M) single nucleotide variants (SNVs), 3.85 M small indels, and 106,382 structural variations. In the association analysis with collected phenotypes, we found that the T allele of rs1549293 in KAT8 significantly correlated with the waist circumference in northern Han males. Moreover, significant genetic diversity in MTHFR, TCN2, FADS1, and FADS2, which associate with circulating folate, vitamin B12, or lipid metabolism, was observed between northerners and southerners. Especially, for the homocysteine-increasing allele of rs1801133 (MTHFR 677T), we hypothesize that there exists a "comfort" zone for a high frequency of 677T between latitudes of 35-45 degree North. Taken together, our results provide a high-quality northern Han reference genome and novel population-specific data sets of genetic variants for use in the personalized and precision medicine.