Research-based learning teaching reform in genetics experimental course for medical undergraduates / 中华医学教育探索杂志

This paper elaborates the specific implementation process of the "research-based learning" teaching reform of genetic experiment in medical undergraduate education, including the change of teaching philosophy among teachers, the integration and expansion of experimental contents, the innovation of classroom-teaching model, the compilation of proper textbook, the update of assessment methods and the establishment of evaluation mechanism for teaching and so on. Preliminary research shows that RBL teaching reform can stimulate medical students' interest and potential in learning, and improve their practical and scientific research innovation ability.

The differential effects of traditional Chinese medicine Danchaiheji on dendritic cells / 天津医药

Objective To explore the effects of traditional Chinese formula Danchaiheji on the differentiation of regula?tory dendritic cells (DCs) and the underlying mechanism. Methods The rat blood serums with or without the formula Dan?chaiheji were prepared. The peripheral blood mononuclear cells were separated from the peripheral venous blood of healthy donors. CD14+monocytes were isolated using CD14+magnetic beads and cultured for 5-7 days to obtain immature dendritic cells (imDCs). Then the cells was divided into control group and Danchaiheji containing rat serum group. Control group was divided into two subgroups (containing LPS and without LPS). Danchaiheji containing rat serum group was also divided into two subgroups (containing LPS and without LPS). The surface markers CD86, CD11b and HLA-DR of DCs were detected by flow cytometry. The level of IL-10 was determined by enzyme-linked immunosorbent assays (ELISA). The proliferation of al?logeneic T-cells was detected by flow cytometry and the expression level of indoleamine 2,3-dioxygenase (IDO) was deter?mined using quantitative real-time PCR. Results DCs treated with the formula Danchaiheji exhibited high CD11b and low CD86 and HLA-DR expression levels as well as promoted the secretion of IL-10. In addition, the drug could inhibit the pro?motion of DCs on the proliferation of T cells, which was associated with the up-regulation of IDO expression. Conclusion The traditional Chinese formula Danchaiheji can induce the differentiation of DCs into regulatory DCs and play a role in in?hibitory effect on immune function.

PCR-HRM Analysis for Gene Mutation Screening in a Child with Osteogenesis Imperfecta / 天津医药

Objective To investigate COL1A1 gene mutation by PCR-high resolution melting (PCR-HRM) and an-alyze the correlation between genotype and clinical phenotype in a child (proband) with osteogenesis imperfecta (OI). Methods The family history of OI pedigree along with the clinical data was collected. Blood samples from the proband and his family members, as well as 50 normal controls, were collected. The mutation of COL1A1 gene was screened using PCR-HRM and validated by the gene sequence. Results The detection of PCR-HRM showed the abnormal result of COL1A1 17 exon in proband with a lower melting temperature (Tm) value than that of normal controls by 0.4℃. There were signifi-cant differences in the standardization melting curve and the different melting curve between the proband and the normal controls. The sequencing result was c.1138G>A, which meant that cDNA of 1138 base G mutation into A. The mutations transformed the amino acid glycine into a serine at amino acid 380(P. Gly 380 Ser), which resulted in missense mutations. The proband’s father and grandmother had the same mutation of COL1A1 gene. The mutation was not found in the proband’s mother and normal controls. There was no report for such mutation in Chinese population. Pedigree analysis showed the fami-ly genetic characteristics of autosomal dominant inheritance. The proband was clinically diagnosed as OI type Ⅳwith more severe clinical phenotype. Conclusion PCR-HRM analysis is a new effective method for genetic screening of OI. COL1A1 mutation of c.1138G>A is a newly discovered mutation in Chinese population. Gly replaced inαhelical domain may lead to a more severe clinical phenotype.

Screening and analysis of a new mutation of COL1A1 gene in a family with osteogenesis imperfecta / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate mutation of COL1A1 gene and analyze the relationship between genotype and clinical phenotype in a family with osteogenesis imperfecta (OI).</p><p><b>METHODS</b>The family history of an OI pedigree, along with clinical data, was collected. Blood samples from the proband and his families, as well as 50 normal controls, were collected. Mutation of COL1A1 gene was screened using PCR-high resolution melting (PCR-HRM) and validated by sequencing.</p><p><b>RESULTS</b>PCR HRM method showed an abnormal result in proband COL1A133_34 exons, which Tm was 87.7℃, in contrast to the normal control (wt) Tm of 87.9±0.06℃. There was a significant difference between the proband and the normal control with the standardization curve and the difference curves. DNA sequencing showed that Y9COL1A1 gene exons 33_34 has lost a C base (c.2321delC), which resulted in a frameshift mutation and caused an premature termination codon (UAA) at amino acid 334, i.e., p.Pro774LeufsX334 The father and grandfather of the proband, both suffered from OI, were verified to be heterozygous for the same mutation. The same mutation was not found in 50 normal controls. Database search confirmed this to be a novel mutation. Pedigree analysis suggested that it has an autosomal dominant inheritance. The proband and patients from the family were clinically diagnosed as OI type I.</p><p><b>CONCLUSION</b>The study has identified a novel mutation of COL1A1 gene, c.2321delC. This frameshift mutation has caused a premature stop codon and reduced collagen type synthesis, characterized by a lighter OI clinical phenotype.</p>