Application of the Biochemistry Hybrid Teaching Mode Based on BOPPPS / 中国生物化学与分子生物学报

In the internet era, massive online open course (MOOC) provides a new research idea and direction for educational reform. The course of biochemistry has the characteristics of many miscellaneous knowledge points, and emphasis on theoretical studies. To overcome students' low interest in learning, the author designed an online and offline hybrid teaching mode based on the BOPPPS teaching method, and carried out the practice in the biochemistry classroom. The situational cases in BOPPPS stimulated the students' interest in learning, and the progressive classroom exercises expanded their horizon. The results show that compared with the students who have experienced blended learning, the depth of knowledge understanding of the experimental group is significantly better than that of the control group, and there is also a significant difference in learning effect (P<0.05). The average score of the experimental group (81. 13) was about 5 points higher than that of the control group (76. 21). The results of the questionnaire survey show that compared with the traditional teaching mode, students are more willing to accept the new teaching mode, and are willing to support the continuation of the teaching mode in the future semesters. Students believe that they can learn more from the new teaching mode than the traditional teaching mode. Moreover, the new teaching mode also promotes teamwork ability, improves students' interest in learning, and students are willing to spend a longer time preparing for the class independently before class. In sum, this method stimulates students' initiative in learning and promotes students to learn better.

Aerobic exercise improves spermatogenesis of male rats: Results of iTRAQ-based proteomic analysis of the testis tissue / 中华男科学杂志

Objective@#To investigate the effect of aerobic exercise on the spermatogenic function of male rats and screen out differentially expressed proteins related to spermatonesis-regulation by proteomic analysis.@*METHODS@#We randomly divided 24 SD male rats into groups A (non-exercise control), B (exercise), and C (weight-bearing exercise), those in the latter two groups made to swim for 60 minutes a day and those in group C bearing a load 3% of the body weight, both 6 times a week for 9 weeks. At 24 hours after the last exercise, we obtained the sperm count, measured the levels of such serum reproductive hormones as testosterone (T), luteotrophic hormone (LH), follicle-stimulating hormone (FSH), and gonadotrophin-releasing hormone (GnRH), and employed isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomic analysis of the testicular tissue.@*RESULTS@#Compared with group A, group C showed significant increases in sperm concentration (［2.12 ± 0.43］ vs ［3.54 ± 0.52］ ×10⁶/ml, P 0.05) and FSH (［20.49 ± 2.44］ vs ［22.29 ± 2.31］ IU/L, P >0.05). No significant changes were observed in sperm concentration or reproductive hormone levels in group B as compared with A. Group B exhibited obviously more mature sperm and cell layers in the seminiferous epithelium than group A. A total of 47 differentially expressed proteins were identified, of which 37 were up-regulated and the other 10 down-regulated. In addition, another 5 significantly differentially expressed proteins closely related to reproductive function were identified, including up-regulated Anx A1, GPX3, Rimbp3, and Dpy19l2 and down-regulated CYP17. Enrichment analysis showed that the differentially expressed proteins were mainly involved in extracellular matrix-receptor interaction, protein digestion and absorption, and focal adhesion pathways.@*CONCLUSIONS@#Proper-intensity exercise can improve the spermatogenic function of rats. Aerobic exercise promotes spermatogenesis mainly by up-regulating the expressions of the proteins related to the production and differentiation of spermatozoa.

Cloning of gdnf in the mouse testis and its expression in sertoli cells / 中华男科学杂志

<p><b>OBJECTIVE</b>To clone the glial cell line-derived neurotrophic factor (GDNF) from the mouse testis, construct the eukaryotic expression vector and transfect this vector into Sertoli cells in order to use the gdnf-transfected Sertoli cells as the feeder layer to cultivate spermatogonial stem cells (SSCs).</p><p><b>METHODS</b>Total RNA was extracted from the testes of normal mature mice and gdnf was cloned and amplified using RT-PCR, inserted into the eukaryotic expression vector and transfected into sertoli cells (TM4 cell line). Immunofluorescence with anti-GDNF antibodies was performed at 40 h following the transfection.</p><p><b>RESULTS</b>gdnf cDNA was cloned successfully, and GDNF expressed after transfected into Sertoli cells.</p><p><b>CONCLUSION</b>This study provides a basis for culturing SSCs with gdnf-transfected Sertoli cells as the feeder layer.</p>

Differential analysis of proteomic profiles between cryptorchid and normal mouse testes / 生理学报

To screen factors related to spermatogonial stem cell (SSC) proliferation, and to investigate the mechanism of infertility caused by cryptorchidism, ten-day-old Kunming (KM) mice were used and experimental cryptorchidism was conducted. On the 35th day after cryptorchid operation, the left testes were fixed in Bouin's fluid and used for histological analysis. The testes of 45-day-old mice were subjected to the same histological analysis, and it was found that they contained germ cells at every stage of development, from SSCs to sperm, indicating that the animals were fully sexually mature at this age. While in experimental cryptorchid mice, the spermatogenesis was arrested at the stage of spermatocytes, and only spermatogonia and primary spermatocytes were present in cryptorchid testes. The proportion of spermatogonia to other types of germ cells was much higher than that in sexually mature mice. On the other hand, the right testes were used for proteomic analysis. The total protein in testes was extracted on the 35th day after cryptorchid operation. The differentially expressed proteins in cryptorchid mice and sexually mature mice were screened and compared by the proteomic techniques. Through the separation of two-dimensional gel electrophoresis (2-DE), 20 differential protein spots were found, and 9 of them were digested and identified by the matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrum. In cryptorchid mice, 6 out of 9 proteins were down-regulated, and 3 were up-regulated. Among these proteins, 4 proteins were identified, and they were Stathmin, phosphatidylethanolamine-binding protein1 (PEBP1), HES-related basic helix-loop-helix protein (HERP), and one unnamed protein (we temporarily named it Px). More Stathmin, PEBP1 and Px were expressed in sexually mature mice than in experimental cryptorchid mice. But HERP1 was the other way round. In the present study, we have screened 4 proteins related to cryptorchidism. It is helpful to study the mechanism of SSC proliferation and infertility caused by cryptorchidism.

17beta-estradiol stimulates proliferation of spermatogonia in experimental cryptorchid mice / 亚洲男科学杂志(英文版)

<p><b>AIM</b>To investigate whether estrogen stimulates the proliferation of spermatogonia or induces spermatogenesis in cryptorchid mice.</p><p><b>METHODS</b>Mice were surgically rendered cryptorchid, then treated with different doses of 17beta-estradiol (E2) s.c. once a day. Mice were killed at sexual maturity (45 days of age), and histological analysis and immunofluorescence were performed. Serum follicle stimulating hormone (FSH), estradiol, testosterone and luteinizing hormone (LH) were measured.</p><p><b>RESULTS</b>Low doses of E2 had no notable effect on spermatogonia, but at higher doses, E2 stimulated the proliferation of spermatogonia.</p><p><b>CONCLUSION</b>E2 has a dose-related mitogenic effect on spermatogonia.</p>

Cloning of Bmi1 cDNA from mouse testis and its expression in E. coli BL21 / 中华男科学杂志

<p><b>OBJECTIVE</b>To produce BMI1 polyclonal antibody, mouse Bmi1 cDNA was cloned from mouse testis and expressed in E. coli BL21.</p><p><b>METHODS</b>Bmi1 gene was amplified from mouse testis by RT-PCR and inserted into the prokaryotic expression vector pET-28c(+). Subsequently the recombined vector was transformed and expressed in E. coli BL21 (DE3) and the immunogenicity of recombined protein BMI1 (rBMI1) was tested by Western blot.</p><p><b>RESULTS</b>Mouse Bmi1 cDNA of 975 bp was successfully cloned and recombined. E. coli BL21 strains expressed rBMI1 were screened. The expression protein amounted to 12% of the total bacterial protein after induced with IPTG, which included inclusion body and soluble protein. Inclusion body was the major pattern of the expression that amounted to 71% of the insoluble protein. Western blot analysis showed that rBMI1 could be specially recognized by mouse monoclonal IgG1 anti-BMI1 and His-tag antibody.</p><p><b>CONCLUSION</b>There was expression of Bmi1 gene in mouse testis. Mouse Bmi1 cDNA was successfully cloned and expressed prokaryoticly.</p>