The tetrapeptide N-acetyl-seryl-aspartyl-lysyl-proline (AcSDKP), a physiological regulator of cell proliferation, has been principally reported as a potent inhibitor of the proliferation of haematopoietic stem cells and progenitors. The purpose of this study was to investigate whether the AcSDKP may directly affect the proliferative potential of human bone marrow mesenchymal stem cells (MSCs) in vitro. We added AcSDKP to the cultures of human bone marrow mononuclear cells and measured the number and average area of MSC colonies. MTT colorimetric assay and mitotic index determination were further used to examine the proliferative state of the third passage MSCs in subcultures with or without the addition of AcSDKP. In addition, we evaluated whether AcSDKP may kill MSCs by the trypan blue dye exclusion test. The results showed that the colony forming capacity, the number of viable cells and the mitotic index were reduced in human bone marrow MSCs cultured in 1x10(-12) mol/L to 1x10(-9) mol/L AcSDKP. Maximum inhibitory activity appeared in 1x10(-11) mol/L of AcSDKP. No difference in percent of living cells was observed between the MSC subcultures with and without the addition of AcSDKP. As a result, AcSDKP within a certain range of concentrations has negatively regulatory effects on the proliferation of human bone marrow MSCs in vitro.
Bone Marrow Cells ; cytology ; Cell Proliferation ; drug effects ; Cells, Cultured ; Down-Regulation ; physiology ; Growth Inhibitors ; physiology ; Humans ; Mesenchymal Stromal Cells ; cytology ; Oligopeptides ; physiology

Objective To investigate the status of psychological quality of college students ' innovation and entrepreneurship, identify the elements of the psychological quality and problems and countermeasures against the psychological quality training in medical schools. Methods A questionair was made and administered to Kunming Medical University students and Chi-square analysis was used to analyze the gender, major, grade, and entrepreneurial intention differences between different groups of students so as to analyze the psychological factors affecting College students ' undertaking intention. Results A total of 1150 questionnaires,1099 was recovered,the effective recovery rate was 95.6％. Psychological quality score was (76.9 ±9.0), good mental qualities only was 8.2％, entrepreneurial environment, factors of psychological quality of good-willed persons were only 0.5％and 15.5％. Female entrepreneurial intentions were better than those of men (<0.001) . Science students' undertaking intention was superior to liberal arts students ( =0.025), knowledge of entrepreneurship difference between knowledge of business groups and <0.005,there was a statistically significant difference, about the environment worse group entrepreneurial intention superior knowledge of business groups. Conclusions As students' psychological qualities are poor,have poor psychological quality,in teaching we should strengthen the cultivation of medical students' entrepreneurial ability and correct understanding of entrepreneurship, create a good business environment, increase the entrepreneurship policy advocacy efforts, and create a good business environment and atmosphere so as to strengthen the entrepreneurship education, improve entrepreneurship courses so that students fully understand the cognitive and psychological qualities, stimulate the entrepreneurial motivation, lay the Foundation for entrepreneurship.

Objective Development of new methods, ELISA and immunostrip test, for the diagnosis of nasopharyngeal carcinoma. Methods The engineering purified antigens coat plate or absorb on nitrocellulose filter. The plate and diagnostic strips carrying antigens were used for detection of IgG antibody in the sera from nasopharyngeal carcinoma patients and outpatients patients. Results 127 cases sera from nasopharyngeal carcinoma patients were parallel detected TK/ IgG antibody by ELISA and immunostrips. The TK/IgG antibody are all positive in the 127 cases of nasopharyngeal carcinoma patients. 55 cases show positive by ELISA, 58 cases positive by immunostrips in 247 cases sera from outpatient. The antibody positive rate to early antigen p54 lower then to TK. Conclusion ELISA and imuunostrips are sensitive and specific means for detection of the IgG antibody to TK of EBV and the diagnosis of nasopharyngeal carcinoma.

Objective: To explore the heterogeneity and correlation of clinical phenotypes and genotypes in children with disorders of sex development (DSD). Methods: A retrospective study of 1 235 patients with clinically proposed DSD in 36 pediatric medical institutions across the country from January 2017 to May 2021. After capturing 277 DSD-related candidate genes, second-generation sequencing was performed to analyzed the heterogeneity and correlation combined with clinical phenotypes. Results: Among 1 235 children with clinically proposed DSD, 980 were males and 255 were females of social gender at the time of initial diagnosis with the age ranged from 1 day of age to 17.92 years. A total of 443 children with pathogenic variants were detected through molecular genetic studies, with a positive detection rate of 35.9%. The most common clinical phenotypes were micropenis (455 cases), hypospadias (321 cases), and cryptorchidism (172 cases) and common mutations detected were in SRD5A2 gene (80 cases), AR gene (53 cases) and CYP21A2 gene (44 cases). Among them, the SRD5A2 mutation is the most common in children with simple micropenis and simple hypospadias, while the AMH mutation is the most common in children with simple cryptorchidism. Conclusions: The SRD5A2 mutation is the most common genetic variant in Chinese children with DSD, and micropenis, cryptorchidism, and hypospadias are the most common clinical phenotypes. Molecular diagnosis can provide clues about the biological basis of DSD, and can also guide clinicians to perform specific clinical examinations. Target sequence capture probes and next-generation sequencing technology can provide effective and economical genetic diagnosis for children with DSD.
3-Oxo-5-alpha-Steroid 4-Dehydrogenase/genetics* ; Child ; China/epidemiology* ; Cryptorchidism/genetics* ; Disorders of Sex Development/genetics* ; Female ; Genital Diseases, Male ; Genotype ; Humans ; Hypospadias/genetics* ; Male ; Membrane Proteins/genetics* ; Penis/abnormalities* ; Phenotype ; Retrospective Studies ; Steroid 21-Hydroxylase/genetics*