Crossover patterns under meiotic chromosome program / 亚洲男科学杂志(英文版)

Repairing DNA double-strand breaks (DSBs) with homologous chromosomes as templates is the hallmark of meiosis. The critical outcome of meiotic homologous recombination is crossovers, which ensure faithful chromosome segregation and promote genetic diversity of progenies. Crossover patterns are tightly controlled and exhibit three characteristics: obligatory crossover, crossover interference, and crossover homeostasis. Aberrant crossover patterns are the leading cause of infertility, miscarriage, and congenital disease. Crossover recombination occurs in the context of meiotic chromosomes, and it is tightly integrated with and regulated by meiotic chromosome structure both locally and globally. Meiotic chromosomes are organized in a loop-axis architecture. Diverse evidence shows that chromosome axis length determines crossover frequency. Interestingly, short chromosomes show different crossover patterns compared to long chromosomes. A high frequency of human embryos are aneuploid, primarily derived from female meiosis errors. Dramatically increased aneuploidy in older women is the well-known "maternal age effect." However, a high frequency of aneuploidy also occurs in young women, derived from crossover maturation inefficiency in human females. In addition, frequency of human aneuploidy also shows other age-dependent alterations. Here, current advances in the understanding of these issues are reviewed, regulation of crossover patterns by meiotic chromosomes are discussed, and issues that remain to be investigated are suggested.

Observation of clinical effect of radiofrequency ablation combined with ozone injection in the treatment of lumbar disc herniation / 中国基层医药

Objective To discuss the application value of radiofrequency ablation in combination with ozone technique in the treatment of lumbar disc prolapse.Methods 150 patients with lumbar disc prolapse were divided into observation group and control group according to the digital table,75 cases in each group.The control group was given radiofrequency ablation treatment,the observation was given radiofrequency ablation in combination with ozone injection treatment.The treatment effect of the two groups was compared.Results The total effective rate of the treatment group was 94.67%,which of the control group was 82.67%,the difference between the two groups was statistically significant (x2=5.374,P<0.05).After treatment,the waist painful disease score,straight leg-raising test angle of the observation group were (25.06±3.56)points,(78.19±15.78)°,which of the control group were (20.13±2.29) points,(60.38±11.86)°,the differences between the two groups were statistically significant (t=10.086,7.813,all P<0.05).Conclusion Radiofrequency ablation combined with ozone technique in the treatment of patients with lumbar disc prolapse can improve the clinical curative effect,and improve the patients' clinical signs,it is worthy of popularizing in clinical application.