1.Determination of global DNA methylation in human leukocyte by isocratic cation exchange high-porformance liquid chromatography
Zheng LI ; Ying LI ; Yongjia YANG ; Fuyou LIU ; Wuqiu LI
Journal of Chinese Physician 2010;12(1):55-58
Objective Improving the existed HPLC methods in order to detect the levels of global DNA methylation rapidly, stably and conveniently. Methods The HP1100 high performance liquid chrom-atographic (HPLC) system was used in this study. The analytic column was Macherey-Nagel (MN) EC 250/4.6 Nucleosil 100-5SA (250mm x 4. 6mm, 5u,m) cation exchange chromatographic column. We used 60mM acetic acid + 15% acetonitrile as mobile phase (adjust to pH =4. 6 by NaOH). The flow rate was 1. 0 ml/min, detective UV wavelength was set to 276 nm and column temperature was set to 28℃. The injection volume was 50μl. The global DNA methylation was expressed as 5mdC/(dC +5mdC) x 100%. Results Under these conditions, we can isolate dC and 5mdC completely in ten minutes. The level of leukocyte global DNA methylation in healthy people is (4. 389 ±0. 0159) %. Conclusions This method can determine the levels of global DNA methylation rapidly, and it can be widely applied in some laboratories.
2.Clinical application of nutritional risk scale in pediatric cancer patients:a review
Chao YAN ; Yonghong LI ; Jing LI ; Runqin HUANG ; Yongjia ZHAN ; Shenghuan YANG
Chinese Journal of Practical Nursing 2023;39(10):789-794
The basic information and clinical application of nutritional risk scales for children with cancer were reviewed, and the strengths and weaknesses of each scale were analyzed. After systematic search and reading, the scales with more clinical applications included universal scales: Pediatric Malnutrition Assessment Screening Tool (STAMP), Nutritional Risk and Stunting Malnutrition Screening Tool (STRONG kids), Pediatric Yorkhill Malnutrition Score (PYMS), Pediatric Subjective Global Nutritional Risk Assessment (SGNA); specific scales: Nutritional Screening Tool for Childhood Cancer (SCAN), Nutritional Risk Screening for Childhood Cancer (NRS-PC). In order to effectively manage the nutritional risk of pediatric cancer patients, we should selectively use and further actively Chinese or develop specific nutritional risk measurement tools adapted to our national conditions.
3.Real-time dissolution of simvastatin tablets manufactured by 3 factories
Yi YANG ; Changjiang WANG ; Yanling GU ; Yongjia SHENG
China Modern Doctor 2014;(14):82-85
Objective To compare the real-time dissolutions of 3 kinds of Simvastatin tablets used in our hospital, and provide reference information for clinical applications. Methods The dissolution rate of simvastatin tablets was deter-mined by the Chinese Pharmacopoeia 2010, and the HPLC method was used to determine the simvastatin content at the wavelength of 238 nm and the Weibull’s equation was adopted to fit the dissolution curves. The shape parameters (m) were performed statistical analysis; Using the similarity f2 as the index, compared the dissolution curve between tablets and the preparation. Results The dissolution of simvastatin tablets manufactured by the 3 manufaccturer was no less than 90% in 30 min, which comply with the national specifications. Compared with the dissolution curve of 6 tablets from the same batch, the homogenicity of samples from A was better, with poor homogenicity of tablets from B or C. There’s significant difference in the shape parameter m of tablets from B and C (P< 0.05), and there’s no significant difference in m of tablets from C and A(P>0.05). Conclusion The in vitro dissolution of the simvastatin tablets are de-termined with single point test procedures. The dissolution of the tablets from 3 manufactures comply with national specifications. However, there’s significant difference in real time dissolution of national tablets. It’s necessary to im-prove the quality of national tablets. Cautions should be taken while use in clinical practices.
4.Genotype and phenotype analysis of two monozygotic twins with neurofibromatosis type 1 but inconsistent congenital pseudarthrosis
Yu ZHENG ; Guanghui ZHU ; Zhengmao HU ; Yaoxi LIU ; Yongjia YANG ; Zhenqing LUO ; Haibo MEI
Chinese Journal of Orthopaedics 2022;42(16):1054-1064
Objective:To compare the genotypes and phenotypes between the monozygotic twins via whole genome sequencing to further clarify the autosomal dominant inherited neurofibromatosis type 1 (NF1) variants related to congenital pseudarthrosis (CP).Methods:According to the diagnostic criteria of congenital tibial pseudarthrosis and the clinical diagnostic criteria of NF1, two pairs of monozygotic twins with NF1 were included. Both were female and only one of each pair had congenital pseudarthrosis. The other did not have congenital pseudarthrosis. Whole genome sequencing was performed using the peripheral blood of the two pairs of monozygotic twins. Customized bioinformatics analysis was then performed to identify single nucleotide variants (SNVs), short insertion deletion variants (InDel), copy number variants (CNVs), and structural variants (SVs). Classified the variants according to the American College of Medical Genetics and Genomics (ACMG) and ClinGen criteria. The germline variants within the monozygotic twins were compared to identify the CP patients' unique variants. The shared pathogenic or likely pathogenic germline variants between the unique variants in the CP patients from the twins were also analyzed. Further, the identified disease-causing variants were validated by Sanger sequencing in the family of the twins and their parents. Finally, the genotypes and phenotypes regarding the pathogenic variants of the NF1 gene among the twins were characterized. Results:Both the two monozygotic twins were identified pathogenic variants in the NF1 gene. One with c.3047_3048del (p.Cys1016SerfsTer4), and the other with c.4267A>G (p.Lys1423Glu). By Sanger sequencing validation in family quads, the two CP patients and their siblings harbored de novo heterozygous variants of the NF1 gene. In addition to the NF1 gene, no other genes were identified pathogenic or likely pathogenic variants uniquely in the CP patients compared with their twin sisters, as well as SVs and CNVs. In addition, by analyzing the rare and damaging variants in the two CP patients from the two twins, they had no overlapping genes against the SNVs, InDels, SVs, or CNVs. Conclusion:Whole genome sequencing revealed that both the two monozygotic twins with NF1 were detected pathogenic variants of gene NF1. No other pathogenic variants specific to the CP patients among the twins were identified. The two CP patients shared no other common genes from the detected likely pathogenic variants.
5.Hemodynamics Study of Internal Carotid Artery:A Comparison Between Unidirectional and Bidirectional Coupled Multi-Scale Model
Jinfeng YANG ; Yongjia GAO ; Chi ZHANG ; Feiyan CHANG ; Deyu LI
Journal of Medical Biomechanics 2019;34(2):E166-E172
Objective To compare the hemodynamic characteristics in internal carotid artery models, which were obtained by multi-scale unidirectional and bidirectional coupling models, so as to provide references for selecting models in further studies. Methods Based on the nuclear magnetic resonance image of one patient with mild stenosis of internal carotid artery, the lumped parameter model of the circle of Willis and the three-dimensional model of internal carotid artery were constructed. Those two different multi-scale models were constructed by unidirectional and bidirectional coupling. Results With the increase of stenosis degree, the inlet and outlet blood pressure and the outlet blood flow of internal carotid artery all decreased under two kinds of coupling method. The distribution of low time average wall shear stress (TAWSS) and high oscillatory shear index (OSI) of the internal carotid artery both increased with the increase of stenosis degree under two kinds of coupling method in general. The anterior cerebral artery segment showed lower shear stress and higher OSI with bidirectional coupling in 70% stenosis, and the blood flow direction of posterior communicating artery was changed, which was significantly different from unidirectional coupling results. Conclusions At a low degree of stenosis, the result of those two kinds of coupling method were consistent in general, but there was a significant difference in 70% stenosis, and the result of bidirectional coupling was closer to physiological parameters. The research findings can be better applied to the hemodynamic study of cerebrovascular diseases.