Sperm chromatin structure assay results after swim-up are related only to embryo quality but not to fertilization and pregnancy rates following IVF

The aim of this study was to investigate whether the sperm chromatin structure assay （SCSA） results after swim-up are related to fertilization rates, embryo quality and pregnancy rates following in vitrofertilization （IVF）. A total of 223 couples undergoing IVF in our hospital from October 2008 to September 2009 were included in this study. Data on the IVF process and sperm chromatin structure assay results were collected. Fertilization rate, embryo quality and IVF success rates of different DNA fragmentation index （DFI） subgroups and high DNA stainability （HDS） subgroups were compared. There were no significant differences in fertilization rate, clinical pregnancy or delivery rates between the DFI and HDS subgroups. However, the group with abnormal DFI had a lower good embryo rate. So, we concluded that the SCSA variables, either DFI or HDS after swim-up preparation, were not valuable in predicting fertilization failure or pregnancy rate, but an abnormal DFI meant a lower good embryo rate following IVF.

On aerodynamic noises radiated by the pantograph system of high-speed trains

Pantograph system of high-speed trains become significant source of aerodynamic noise when travelling speed exceeds 300 km/h. In this paper, a hybrid method of non-linear acoustic solver （NLAS） and Ffowcs Williams-Hawkings （FW-H） acoustic analogy is used to predict the aerodynamic noise of pantograph system in this speed range. When the simulation method is validated by a benchmark problem of flows around a cylinder of finite span, we calculate the near flow field and far acoustic field surrounding the pantograph system. And then, the frequency spectra and acoustic attenuation with distance are analyzed, showing that the pantograph system noise is a typical broadband one with most acoustic power restricted in the medium-high frequency range from 200 Hz to 5 kHz. The aerodynamic noise of pantograph systems radiates outwards in the form of spherical waves in the far field. Analysis of the overall sound pressure level （OASPL） at different speeds exhibits that the acoustic power grows approximately as the 4th power of train speed. The comparison of noise reduction effects for four types of pantograph covers demonstrates that only case 1 can lessen the total noise by about 3 dB as baffles on both sides can shield sound wave in the spanwise direction. The covers produce additional aerodynamic noise themselves in the other three cases and lead to the rise of OASPLs.

Assessment of Uterine Receptivity by Endometrial and Subendometrial Blood Flows Measured by Vaginal Color Doppler Ultrasound in Women Undergoing IVF Treatment

Objective To evaluate endometrial and subendometrial blood flows measured by vaginal color Doppler ultrasound as a predicator of endometrial receptivity in women undergoing IVF treatment. Methods A total of 119 infertile patients undergoing the first IVF/ICSI-ET cycle were recruited. Three groups were divided according to a color Doppler ultrasound examination performed on the day of hCG injection. Group A, endometrial and subendometrial blood flows were 2 branches and below; group B, endometrial and subendometrial blood flows were between 3 and 4 branches; group C, endometrial and subendometrial blood flows were 5 branches and above. Patients were transferred 1-3 embryos each. Demographic data, ovarian responses, endometrial thickness, PI, RI, development of embryo and IVF result among groups were compared. Results Demographic data, ovarian responses, endometrial thickness, PI, RI and development of embryo among groups have no significant difference. The pregnancy rate of group A was significantly lower than that of group B （P〈0.05） and group C （P〈0.01）. The implantation rate of group A was significantly lower than than of group C （P〈0.01）. There was no significant difference of the rate of pregnancy and implantation between group B and group C （P〉0.05）. Conclusion Endometrial and subendometrial blood flows measured by vaginal color Doppler ultrasound is a good predicator of pregnancy during IVF treatment. A good endometrial and subendometrial blood flows is benefit for the result of IVF.

Revised Super-long Down-regulation Protocol Improves the Outcome of Infertile Patients with Repeated Implantation Failure in IVF/ICSI-ET

Objective To investigate the outcome of revised super-long down-regulation protocol （RSDP） for in vitro fertilization / intracytoplasmic sperm injection-embryo transfer （1VF/1CS1-ET） in the special infertile patients with repeated implantation failure （RIF）. Methods Patients with RIF were divided into RSDP group and routine long downregulation protocol （RLDP） group. In RSDP group, gonadotropin releasing hormone agonist （GnRHa） was injected intramuscularly by 2.5 mg in mid-luteal phase for the ftrst time and 1.25 mg after 28 d; gonadotropin （Gn） was started 14 d later after the second GnRHa dose. IVF/ICSI-ET was performed according to the routine procedure. The clinical outcomes of RSDP group were compared with those of RLDP group. Results In RSDP group, the number of retrieved oocytes and valid embryos was significantly lower （P〈0.05）; there were no significant differences about fertilization rate （P〉0. 05）; both good-quality embryo rate and implantation rate were significantly increased （P〈0. 005）; clinical pregnancy rate was obviously improved （P〈0. 05）, as compared with RLDP group.Conclusion RSDP can improve the IVF outcomes significantly in RIF patients.

Endometrial Collagen Fibril Hyperplasia is Associated with Implantation Failure in Women Undergoing IVF-ET

Objective To analyse the effects of controlled ovarian hyperstimulation （ COH） on the endometrial expression of collagen fibril （CF） during the peri-implantation period in patients undergoing IVF, and its relation to endometrial receptivity （ER） in repeated implantation failure（RIF）. Methods Peripheral blood and endometrial biopsies were obtained from 45 infertile women on days 5, 7 or 9 after oocytes retrieval or ovulation in a stimulated cycle （SC） and natural cycle （NC） respectively. CF was assayed by transmission electron microscope and quantified by modified Masson dyeing. The outcome of subsequent embryo transfer（ET） was observed. Results Levels of both E2 and progesterone were higher in the peripheral blood in SC than in NC. Also the expression of CF in the stroma in each secretory phase was increased significantly in SC （P 〈O.05）. After embryo transferring, expression levels of CF in the pregnancy group dropped between the mid- and late-secretory phase, but no change in the non-pregnancy group. In the same term, all patients undergone endometrial curettage had higher pregnancy rate than those without. Conclusion Imbalance of production and degradation of endometrial CF in the secretory phase resulting from COH may be the cause of defective ER and implantation failure in some RIF patients. Endometrial curettage may improve implantation rate by inducing appropriate CF hyperplasia and degradation.