Triploid shellfish are useful for aquaculture because of their sterility,superior growth and improved meat quality.Tetraploid are also valuable for 100% producing triploids through mating with diploid.We tested polypl...Triploid shellfish are useful for aquaculture because of their sterility,superior growth and improved meat quality.Tetraploid are also valuable for 100% producing triploids through mating with diploid.We tested polyploid induction in Japanese scallop,Patinopecten yessoensis,by inhibiting polar body Ⅰ (PB group) and both polar bodyⅠandⅡ (PPB group) in newly fertilized eggs.Cytochalasin B (0.6 mg/L) was applied at 11～22 min post fertilization (PF),and terminated in PB group when polar body Ⅰ was released about 70% in untreated eggs,in PPB group when polar lobe was observed in control group.The treatment and its control were repeated 5～7 times using different pairs of parents.The ploidy was determined by counting chromosome number at embryo stage,and then was detected by flow cytometry (FCM) at larvae stage and juvenile stage.\;In PB group,aneuploid (31.13%),triploid (3.96%),tetraploid (17.46%) and pentaploid (46.65%) embryos were produced,and in PPB groups,pentaploid embryos became higher (56.2%),triploid and tetraploid were 2.42% and 9.11%.At day 3 PF,the larvae showed tetraploid,pentaploid and aneuploid peaks through checking with FCM in PB group,and showed mainly higher pentaploidy peak in PPB groups.However,at day 14 PF diploids were mainly left,sometimes with small triploid peak.It suggested that most tetraploid,aneuploid and pentaploid larvae were died within the first two weeks PF.At three months PF,a few diploid juveniles were harvested in three control groups.Only 12 juvenile scallops were harvested in one of treated group (PB-7),and 11 of them died accidentally,the alive one in treated group was triploid through checking with FCM.展开更多
It is proved that if K is an origin-symmetric convex body in R^2 and Π^*K is the polar projection body of K,then the volumes of K and Π^*K satisfy the inequality V(K)V(Π^*K)≥2 with equality if K is a parallelogram.
Objective To evaluate the application value of rescue ICSI in fertilization failure after conventional IVF and choose the best rescue window before oocyte aging according to the results of rescue ICSI performed in dif...Objective To evaluate the application value of rescue ICSI in fertilization failure after conventional IVF and choose the best rescue window before oocyte aging according to the results of rescue ICSI performed in different time. Methods The data of 93 IVF cycles were analyzed retrospectively. Rescue ICSI was performed in these cycles after conventional IVF failure. Because of the different rescue time, these cycles were divided into two groups： early rescue group （group A, 77 cycles, rescue ICSI performed 4-8 h after conventional IVF） and late rescue group （group B, 16 cycles, rescue ICSI performed 20-22 h after conventional IVF）. Results There were no statistically significant differences in age of female, duration of infertility, number of oocytes retrieved every cycle. The normal fertilization rate, pregnancy rate and implantation rate were decreased in group B compared with those in group A （P〈0.05）. In group A, the normal fertilization rate of rescue ICSI performed 4-6 h after conventional IVF （group A1） was increased compared with that of rescue ICSI performed 6-8 h （including 6 h） after conventional IVF （group A2）（66.5% vs 55.9%）（P〈0.05）; while the abnormal fertilization rate in group A1 was decreased compared with group A2 （9.0% vs 14.4%）（P〈0.05）. Clinical pregnancy rate was slight higher in group A1 than in group A2, though this failed to be significantly different. Conclusion Rescue ICSI is effective if fertilization was failure after conventional IVF, the most important thing is to choose the reasonable rescue window before oocyte aging when ICSI is performed.展开更多
The freshwater giant prawn, Macrobrachium rosenbergii is of great economic importance in many coun-tries. It's farmed production is recorded globally. We examine the fertilization cytology in the hope that theymay...The freshwater giant prawn, Macrobrachium rosenbergii is of great economic importance in many coun-tries. It's farmed production is recorded globally. We examine the fertilization cytology in the hope that theymay serve to augment the previous reports on this subjects and to provide some basis for artificial breedings.This paper is about the changes of eggs during fertilization.展开更多
文摘Triploid shellfish are useful for aquaculture because of their sterility,superior growth and improved meat quality.Tetraploid are also valuable for 100% producing triploids through mating with diploid.We tested polyploid induction in Japanese scallop,Patinopecten yessoensis,by inhibiting polar body Ⅰ (PB group) and both polar bodyⅠandⅡ (PPB group) in newly fertilized eggs.Cytochalasin B (0.6 mg/L) was applied at 11～22 min post fertilization (PF),and terminated in PB group when polar body Ⅰ was released about 70% in untreated eggs,in PPB group when polar lobe was observed in control group.The treatment and its control were repeated 5～7 times using different pairs of parents.The ploidy was determined by counting chromosome number at embryo stage,and then was detected by flow cytometry (FCM) at larvae stage and juvenile stage.\;In PB group,aneuploid (31.13%),triploid (3.96%),tetraploid (17.46%) and pentaploid (46.65%) embryos were produced,and in PPB groups,pentaploid embryos became higher (56.2%),triploid and tetraploid were 2.42% and 9.11%.At day 3 PF,the larvae showed tetraploid,pentaploid and aneuploid peaks through checking with FCM in PB group,and showed mainly higher pentaploidy peak in PPB groups.However,at day 14 PF diploids were mainly left,sometimes with small triploid peak.It suggested that most tetraploid,aneuploid and pentaploid larvae were died within the first two weeks PF.At three months PF,a few diploid juveniles were harvested in three control groups.Only 12 juvenile scallops were harvested in one of treated group (PB-7),and 11 of them died accidentally,the alive one in treated group was triploid through checking with FCM.
基金Supported by the Funds of the Basic and Advanced Research Project of CQCSTC(cstc2015jcyjA00009)Scientific and Technological Research Program of Chongqing Municipal Education Commission(KJ1500628)
文摘It is proved that if K is an origin-symmetric convex body in R^2 and Π^*K is the polar projection body of K,then the volumes of K and Π^*K satisfy the inequality V(K)V(Π^*K)≥2 with equality if K is a parallelogram.
文摘Objective To evaluate the application value of rescue ICSI in fertilization failure after conventional IVF and choose the best rescue window before oocyte aging according to the results of rescue ICSI performed in different time. Methods The data of 93 IVF cycles were analyzed retrospectively. Rescue ICSI was performed in these cycles after conventional IVF failure. Because of the different rescue time, these cycles were divided into two groups： early rescue group （group A, 77 cycles, rescue ICSI performed 4-8 h after conventional IVF） and late rescue group （group B, 16 cycles, rescue ICSI performed 20-22 h after conventional IVF）. Results There were no statistically significant differences in age of female, duration of infertility, number of oocytes retrieved every cycle. The normal fertilization rate, pregnancy rate and implantation rate were decreased in group B compared with those in group A （P〈0.05）. In group A, the normal fertilization rate of rescue ICSI performed 4-6 h after conventional IVF （group A1） was increased compared with that of rescue ICSI performed 6-8 h （including 6 h） after conventional IVF （group A2）（66.5% vs 55.9%）（P〈0.05）; while the abnormal fertilization rate in group A1 was decreased compared with group A2 （9.0% vs 14.4%）（P〈0.05）. Clinical pregnancy rate was slight higher in group A1 than in group A2, though this failed to be significantly different. Conclusion Rescue ICSI is effective if fertilization was failure after conventional IVF, the most important thing is to choose the reasonable rescue window before oocyte aging when ICSI is performed.
文摘The freshwater giant prawn, Macrobrachium rosenbergii is of great economic importance in many coun-tries. It's farmed production is recorded globally. We examine the fertilization cytology in the hope that theymay serve to augment the previous reports on this subjects and to provide some basis for artificial breedings.This paper is about the changes of eggs during fertilization.
