Too old for IVF: are we discriminating against older women?

In vitro fertilization (IVF) in women of advanced age (>42 years) represents only 5%, a comparatively minute part, of the national IVF experience in the United States (US). In view of evolving population dynamics, it, however, also represents proportionally a rather quickly expanding patient need. Because of access restrictions at many IVF programs, this market does not live up to its potential. As best demonstrated by the 2004 US National Summary and Fertility Clinic Report, which for the first time reported pregnancies and births above age 45 year, IVF in women of advanced reproductive age represents a cutting edge area of interest for improving current IVF outcomes. Access to IVF should, therefore, not be withheld based on female age and/or baseline FSH levels. Instead, a definition of acceptable minimal pregnancy and life birth rates could be used to define the limits of offered access to IVF, independent of age and/or baseline FSH levels.     

人类卵母细胞减数分裂进程及形态学研究

目的对人类未成熟卵母细胞进行体外培养,观察卵母细胞直径和卵周隙随卵母细胞成熟所发生的形态学改变,并按照其染色体变化确定人类卵母细胞减数分裂进程。方法穿刺收集多囊卵巢患者未成熟卵母细胞进行体外培养成熟,分别于体外培养4、8、12、16、20、24和28h进行卵母细胞直径及最大卵周隙测量,然后行染色体形态学观察并进行分析。结果未成熟卵母细胞体外培养10h约有50％发生生发泡破裂（GVBD）恢复减数分裂;减数分裂Ⅰ（MⅠ）前中期由培养8h的31．37％上升到16h的45％,然后下降;MⅠ中期（Meta-MⅠ）在培养20h进入高峰,占到40．63％,MⅠ后、末期（Ana／tel-MⅠ）维持时问相对较短,24h后多数已进入减数分裂Ⅱ（MⅡ）成熟期,28h未成熟卵母细胞体外培养的成熟率为68．85％。另外发现随着卵母细胞的体外成熟,其直径不会发生明显改变,但卵周隙（PVS）却在逐步增加。结论按照常规的体外培养方法可大致确定人类未成熟卵母细胞的体外成熟进程,且认为卵周隙的扩大可作为卵母细胞成熟分期的另一标志。     

Effects of M II stage oocytes zona pellucida birefringence on pregnancy outcome

ObjectiveTo explore the effects of different M II stage oocytes zona pellucida birefringence on pregnancy outcome.MethodsA total of 46 couples with infertile which induced by single cause received in-vitro fertilization treatment were analyzed retrospectively, and randomly divided into the high zona birefringence (HZB)/HZB group, HZB/low zona birefringence (LZB) group and LZB/LZB group according to different oocytes zona pellucida birefringence. Intracytoplasmic sperm injection outcome was analyzed and compared.ResultsThe proportion of HZB oocytes, implantation rate and the pregnancy rate were decreased in three groups (HZB/HZB group>HZB/LZB group>LZB/LZB group) (P<0.05). But there was no significantly different between the number of oocytes and fertilization rate of these groups (P>0.05). Logistic regression analysis showed that factors affect M II stage oocytes zona pellucida birefringence were age, basal FSH level and the LH level on the day of HCG injection. Age and FSH levels were negatively correlated with the single oocyte zona pellucida birefringence; While the LH level on the day of hCG injection was positively correlated with the single oocyte zona pellucida birefringence.ConclusionsThe primary influence factors on M II stage oocytes zona pellucida are age, basal FSH level and the LH level on the day of hCG injection. The birefringence value of zona pellucida can affect the pregnancy outcome.     

未促排卵的未成熟卵母细胞体外培养成熟治疗不孕症40例分析

目的比较未促排卵的未成熟卵母细胞体外培养成熟(IVM)治疗多囊卵巢综合征(PCOS)和正常月经周期伴不孕患者的临床疗效。方法回顾性分析2004年8月至2005年1月温州医学院第一医院收治的40例不孕患者,接受54个周期的IVM治疗,其中难治性PCOS不孕患者26例35个周期(A组),月经周期正常且经其它辅助生育技术失败的不孕患者14例19个周期(B组),均未采用任何药物刺激。结果共有7个周期取消,其中A组1个,取消率为2.8%;B组6个,取消率为31.6%,差异有极显著性意义(P<0.01)。有胚胎移植的47个周期中,两组的平均获卵数、体外成熟率、正常受精率和卵裂率、平均移植胚胎数差异无显著性意义(P>0.05)。A组1例生化妊娠,15例临床妊娠,B组4例临床妊娠。两组每穿刺周期的临床妊娠率(42.9%、21.1%)差异有极显著性意义(P<0.01),每移植周期的临床妊娠率、种植率和多胎率差异无显著性意义(P>0.05)。结论未促排卵的IVM技术治疗不孕症,尤其对于难治性PCOS不孕更是一种有效的方法。     

玻璃化冷冻方法中冷冻保护剂及制冷速度对家兔卵母细胞纺锤体的影响

目的:探讨玻璃化冷冻方法中冷冻保护剂及制冷速度对家兔第二次减数分裂中期卵母细胞纺锤体的影响.方法:以冷冻环为载体,单用乙二醇(ethylene glycol,EG)或乙二醇与二甲基亚砜(dimethyl sulphoxide,DMSO)联合作冷冻保护剂,用直投液氮或使用玻璃化冷冻仪高速制冷冷冻家兔卵母细胞;解冻2 h后固定并免疫荧光法染色纺锤丝及染色体;用共聚焦扫描显微镜观察纺锤体形态.结果:在单用EG以及EG和DMSO联合直投液氮的方案中,纺锤体损伤较严重,但在EG和DMSO联合应用并采用玻璃化冷冻仪提高制冷速度的方案中,纺锤体形态正常的比例与对照组相似.结论:玻璃化冷冻方法中采用冷冻保护剂联合及采用玻璃化冷冻仪高速制冷对保持解冻后家兔卵母细胞纺锤体形态效果最好.     

In vitro inhibition of recombinant ligand-gated ion channels by high concentrations of milnacipran

Rationale Tricyclic antidepressants are known to inhibit various ligand-gated ion-channel (LGIC) receptors, and some of their clinical features may be associated with this activity. The effects of milnacipran, a selective inhibitor of the reuptake of serotonin and noradrenaline, on LGIC receptors have not yet been investigated on such ion-channel receptors.Objectives To determine the in vitro effect of milnacipran on four recombinant LGIC receptors, nicotinic acetylcholine, N-methyl-d-aspartate, -amino butyric acid (GABA) and 5-hydroxytryptamine_3A receptors.Methods Receptors were expressed in Xenopus oocytes and LGIC activity measured using a two-voltage clamp technique.Results There was no interaction at the GABA receptor. The results at the other LGIC receptors showed that they could be inhibited by high concentrations of milnacipran.Conclusions At high concentrations, milnacipran can inhibit certain LGICs. It is, however, unlikely that these interactions have any clinical consequence under normal therapeutic conditions, since the concentrations required are considerably higher than those achieved in plasma of treated patients.     

卵母细胞体外成熟预防卵巢过度刺激综合征的应用

目的:探讨卵母细胞体外成熟预防卵巢过度刺激综合征(ovarian hyperstim- ulation syndrome,OHSS)的效果。方法:51例IVF长方案超排卵过程中出现OHSS早期征象时,按患者意愿分成两组,实验组于当天注射人绒毛膜促性腺激素(hCG)36h后取卵,经体外培养成熟行体外受精、胚胎移植;对照组则继续按常规用药方案及受精方案行胚胎移植。测定两组出现OHSS早期征象当日的E_2、统计FSH用药天数、用药量、受精率及临床妊娠率。结果:实验组与对照组在出现OHSS早期征象当日的血E_2水平、受精率、优质胚胎率、临床妊娠率无统计学差异;但实验组的FSH总用量、FSH用药天数、获卵数方面显著低于对照组(P<0.05)。实验组1例发生中度OHSS,对照组则发生3例重度OHSS和2例中度OHSS,重度OHSS发生率差异极显著(P<0.01)。结论:超排卵过程中,出现OHSS早期征象时改行卵母细胞体外成熟培养技术可有效地降低OHSS的发生率。     

H+ ion modulation of C-type inactivation of Shaker K+ channels

 The participation of an extracellular loop in C-type inactivation of voltage-gated K⁺ channels was investigated. A wild-type phenylalanine (at position 425) between the fifth putative transmembrane segment (S5) and the pore region of the Shaker K⁺ channel was mutated to a histidine and the functional consequences of protonating the imidizole group of the histidine were examined. C-type inactivation of both wild-type and mutant channels was sensitive to external pH over the range of 5.2–8. The pH dependence of wild-type channels was characterized by an apparent pK value of 5.0. The inactivation kinetics of F425H mutant channels had a pH dependence with a pK of 5.8 – in addition to the pH dependence of the wild-type channels. Moreover, at pH 7 and 8 the voltage dependence of C-type inactivation kinetics was manifest only in the F425H mutant channels. C-type inactivation in wild-type channels involves a chemical group with a low pK. Taken together, these results suggest that residues located in the extracellular S5-pore loop of the Shaker K⁺ channel participate in C-type inactivation. Received: 30 September 1998 / Received after revision: 8 January 1999 / Accepted: 18 January 1999     

高血糖对小鼠卵母细胞Ca2+振荡和卵泡颗粒细胞肿瘤坏死因子相关凋亡诱导配体表达的影响

目的 探讨高血糖对小鼠卵母细胞Ca2+振荡和卵泡颗粒细胞肿瘤坏死因子相关凋亡诱导配体(TRAIL)表达的影响.方法 出生后20d ICR雌鼠,用链脲酶素建立急性高血糖模型;高血糖模型雌鼠及正常雌鼠注射10IU/只孕马血清促性腺激素(PMSG)和人绒毛膜促性腺激素(hCG)超排卵,注射hCG后0h、2h、6h和10h取生发泡(GV)期卵母细胞,双光子激光扫描共焦显微镜检测GV期卵母细胞的Ca2+振荡;hCG注射后6h、10h取卵丘-卵母细胞复合体(COC),利用免疫荧光、Western blotting检测TRAIL的表达.结果 1.高血糖组卵母细胞Ca2+振荡频率高于正常对照组,于hCG注射后2h、6h差异显著(P<0.05);2.免疫荧光、Western blotting蛋白半定量检测显示,高血糖组颗粒细胞TRAIL表达量高于正常对照组,于hCG注射后6h、10h差异有显著性(P<0.05).结论 高血糖加快小鼠未成熟卵母细胞Ca2+振荡的频率;高血糖促进小鼠卵泡颗粒细胞TRAIL的表达.