维生素E对人精子冻融氧化应激损伤的保护作用

目的:探讨水溶性维生素E(Trolox)对冻融人精子氧化应激损伤的可能保护作用及机制。方法:选取16份健康生育男性的精液标本,分析精液常规参数及动力学参数后,将每份精液一式4份,1∶1加入冷冻保护液后混匀,不含水溶性维生素E者设为阴性对照组(G0),而G1、G2、G3实验组混合液中分别含有50、100、200μmol/L浓度的水溶性维生素E,冷冻复苏精液常规分析,检测复苏后精液中活性氧(ROS)水平,采用硫巴比妥酸法(TBA)检测精子中脂质过氧化产物丙二醛(MDA)浓度。结果:冻融后各组精子运动参数较新鲜精液参数均明显下降(P0.01),G2组前向运动精子百分率[(53.33±5.63)%]较对照组[(47.85±5.09)%]明显改善(P0.05),精子VCL和VAP高于阴性对照组(P0.05)。G2组与G3组的ROS及MDA均低于阴性对照组(P0.05)。结论:在精液冷冻保护液中添加一定浓度的水溶性维生素E可以减少精子冻融过程中产生的过量ROS,减轻ROS对精子质膜的氧化应激性损伤,从而提高冻融后的精子活力。     

少弱精子冷冻保存在宫腔内人工授精中的应用

目的:探讨精液冷冻保存在少弱精子症患者行宫腔内人工授精(IUI)周期中的应用效果。方法:2008年3月至2009年6月103对原发性不孕夫妇,共计152个IUI治疗周期,其中精液正常者53个周期(组1),少弱精子者52个周期(组2),少弱精子经精液冷冻保存后结合新鲜精液者47个周期(组3)。检测治疗前后精液常规、精液处理后前向活动精子总数,随访3组患者治疗期间配偶妊娠结局。结果:精液处理前组3精液体积、精子活率、a级精子均低于组2,差异极显著(P<0.01);组3处理后前向活动精子总数高于组2,但差异无显著性(P>0.05)。3组间生化妊娠率和临床妊娠率均无显著性差异。结论:精液冷冻保存可以增加少弱精子症患者前向活动精子总数,精液冷冻保存技术可以在一定程度上提高其IUI妊娠率。精液冷冻保存与IUI相结合,可能是治疗少弱精子症一种较为理想的方法。     

精液粘度与精液分析参数、解脲支原体感染和抗精子抗体关系分析

目的探讨精液粘度增高导致男性不育的机理。方法共4337例不育门诊就诊者,分为精液粘度增高和正常组,观察粘度与主要精液常规参数、UU感染率和AsAb阳性率关系。结果精液粘度增高率为65.02%。粘度增高组精子活动率、a,b级活力精子率显著低于粘度正常组(P<0.05,P<0.001);畸形精子率、液化时间均明显高于粘度正常组(P<0.001);两组精液量、精子密度和精液pH比较无显著性差异(P>0.05)。精液白细胞>5个/HP组粘度增高率明显高于白细胞<5个/HP组(P<0.001)。粘度增高组精浆AsAb阳性率和精液UU阳性率均明显高于粘度正常组(P<0.001)。结论精液粘度可影响精液参数,并与精液白细胞数、精浆AsAb和UU感染有关。     

抗坏血酸盐、过氧化氢酶改善冻融人精子质量的研究

目的 探讨抗氧化剂--抗坏血酸盐、过氧化氢酶(catalase,CAT)、超氧化物歧化酶(superoxide dismutase,SOD)对冻融人精子质量的影响.方法 30份健康可生育男性精液分别添加改良人精子冷冻保护液,依所添加的抗氧化剂及终浓度分7组:未添加者为阴性对照组,余为抗坏血酸盐300、600 μmol/L组,CAT 200、400 U/ml组,SOD 200、400 U/ml组.检测各组精液冻融前后常规参数,冻融后活性氧(reactive oxidative species,ROS)水平、线粒体膜电位(△Ψm)和早期凋亡事件(Ann+PI-%、Ann-PI-%).结果 ①冻融后各组a+b级精子均比冷冻前下降(P＜0.01),但抗坏血酸盐300 μmol/L组与2种浓度的CAT组a+b级精子(43.5±10.0)%、(43.9±8.2)%、(44.3±9.4)%下降少于对照组(38.1±7.9)%,P＜0.05、P＜0.01、P＜0.01;相对应组的精子活率复苏率分别为(67.2±14.1)%、(68.4±13.8)%、(68.8±14.8)%,也高于对照组(58.8±10.1)%,P＜0.05、P＜0.01、P＜0.01;而这3组ROS水平(29.6±12.8)%、(30.0±11.2)%、(31.1±11.0)%则分别低于对照组(36.7±17.0)%,P值均＜0.05.②2种浓度CAT组的△Ψm(34.6±12.9)%、(32.9±11.2)%均高于对照组(27.5±10.8)%,P＜0.01、P＜0.05;而且低浓度抗坏血酸盐组和CAT组凋亡(Ann+PI-%)的精子(15.3±3.0)%、(15.6±2.2)%,以及未出现凋亡(Ann-PI-%)的活精子(14.0±3.8)%、(13.2±2.6)%分别低于对照组(18.1±3.9)%(P值均＜0.01)和高于对照组(10.1±4.0)%(P值均＜0.01).余实验组的检测指标与对照组相比,差异无统计学意义(P＞0.05).③冻融后各实验组a+b级精子,抗坏血酸盐600 μmol/L组、2种浓度CAT组、SOD 400 U/ml组的△Ψm,以及抗坏血酸盐组、CAT 200 U/ml组、SOD 200 U/ml组的Ann-PI-%均分别与对应组的ROS水平呈负相关;而抗坏血酸盐组、CAT 200 U/ml组的Ann+PI-%则与对应组的ROS水平呈正相关,P＜0.05或P＜0.01.结论 在精液冷冻保护剂中添加一定浓度的抗坏血酸盐、CAT可改善冻融人精子质量.     

不育男性抗苗勒管激素与生殖激素及精液质量参数关系的研究

目的探讨男性不育患者精浆和血清抗苗勒管激素(AMH)与血清生殖激素及精液参数之间关系。方法选取2018年9~12月于我院生殖中心就诊的男性不育患者107例,按照《世界卫生组织人类精液检查与处理实验室手册(第五版)》操作规范检测精液体积、精子浓度、前向运动精子(PR)百分比、精子顶体酶、精子DNA完整性、正常形态精子率,根据精液参数分为4组:少精子症组(n=15)、弱精子症组(n=26)、少弱精子组(n=31)、正常精子组(n=35),比较各组患者精浆和血清AMH及血清FSH、LH、催乳素(PRL)、T、E 2之间的差异,并对精浆和血清AMH与生殖激素及精液参数的相关性进行统计分析。结果弱精子症组血清AMH水平高于其他3组,但各组间差异无统计学意义(P>0.05);正常精子组精浆AMH水平[中位数(四分位距)]为1.28(7.71)ng/ml,显著高于少精子症组[0.11(1.26)ng/ml]和少弱精子组[0.16(2.15)ng/ml](P<0.05)。相关性分析显示,血清AMH与生殖激素及精液参数不存在相关(P>0.05);精浆AMH与血清FSH、LH呈负相关(P<0.05),与血清T呈正相关(P<0.05);精浆AMH与精子总数、精子浓度、PR%呈正相关(P<0.05),与其他精液参数不相关(P>0.05)。结论不育男性精浆AMH与血清生殖激素及精子浓度、活力具有一定的相关性,一定程度上反映睾丸生精功能,对男性不育的诊断和治疗有一定的参考作用。     

体外受精-胚胎移植术中使用冷冻供精及夫精的临床效果观察

目的 观察比较IVF-ET中使用冷冻供精及夫精的临床效果,了解正常精液经冷冻保存后使用是否影响IVF-ET的效果。方法 回顾本院常规IVF-ET中使用新鲜夫精172周期(夫精组)及采用冷冻供精47个周期(供精组)资料,对两组的精液情况、受精率、卵裂率以及临床妊娠率进行分析比较。结果 冷冻供精组在精子密度、精子总活动率、前向运动精子率3项指标均低于新鲜夫精组(P<0.01),而受精率、卵裂率、临床妊娠率两组比较无显著性差异(P>0.05)。结论 正常精液经冷冻保存后,尽管精液各项参数有一定改变,但对IVF-ET中受精率、卵裂率及临床妊娠率无明显影响。     

白蛋白与卵黄联合应用于人类精液冷冻保存的研究

目的:初步探讨白蛋白与卵黄两种蛋白联合应用于人类精液冷冻保存的效果,以期为人类精液冷冻提供一种更为有效的冷冻保护液。方法:以卵黄甘油柠檬酸钠作为对照组,其内加不同浓度的白蛋白(1、2、3、4、5 g/L)作为实验组,对人类精液进行冷冻保存,冷冻前后运用计算机辅助精液分析系统(CASA)进行精子运动参数分析;在实验组中选用冷冻复苏后精子运动参数最佳的加1 g/L白蛋白的卵黄甘油柠檬酸钠组及卵黄甘油柠檬酸钠对照组,进行精子存活率、膜功能、线粒体功能、超微结构比较分析。结果:加1 g/L白蛋白的卵黄甘油柠檬酸钠组,其精子活率、活力明显高于对照组及其他实验组(P<0.05);精子存活率、精子头部未着色率明显高于对照组(P<0.05);精子琥珀酸脱氢酶活性明显高于对照组(P<0.01);精子超微结构优于对照组。结论:白蛋白与卵黄两种蛋白联合应用冷冻保存人类精液的效果优于单用卵黄,且白蛋白的作用与其使用浓度有关;白蛋白与卵黄联合使用在人精液冷冻保存中可能具有相加和互补功能。     

冷冻保存对人精子运动特征的影响

目的研究冷冻保存前后供精者精子运动特征的变化,了解冷冻保存对人精子受精潜能的影响。方法供精者精液标本68例,按照世界卫生组织推荐的方法和仪器行精液常规分析和计算机辅助精子分析(CASA)。入选精液加入甘油-卵黄-柠檬酸钠精子冷冻保护剂,行液氮蒸汽冷冻,1个月后复温,再次行CASA。结果冷冻后精子运动学参数中精子头侧摆幅度(ALH)和鞭打频率(BCF)升高,其它所有运动学参数均降低。精子动动学参数中除中速动动(Medium)、慢速运动(Slow)、平均路径速度(VAP)、直线运动速度(VSL)、ALH外,人精子冷冻前和解冻后各个参数都有显著的正相关(P<0.05)。除Medium、Slow、(曲线速度)VCL、ALH外,供精者精子各项参数冷冻前和解冻后比较,差异均有统计学意义(P<0.05)。冷冻复温后VCL>25μm/s、VSL>25μm/s。结论冷冻保存后人精子运动能力降低,但仍具有受精潜能。CASA用于冷冻精液的评估有一定的临床应用价值。     

精液冻存时间对精液质量及受孕能力的影响

目的旨在探讨供精精液冻存时间对精液质量及受孕能力的影响。方法回顾性分析广东省人类精子库280对夫妇使用供精冷冻精液成功怀孕在再次生育时使用同一供精者精液用于人工授精技术的临床使用、随访反馈等相关资料。结果已确认妊娠的人工授精周期复苏后供精精液质量如下:精子浓度,首次生育时(67.5±19.8)×10^6/m L,再次生育时(69.3±21.7)×10^6/m L,两组差异无统计学意义(P>0.05);前向运动精子百分比,首次生育时(54.7±8.8)%,再次生育时(51.0±7.0)%,两组差异有统计学意义(P<0.05)。再次生育精液与首次生育精液的冻存时间差与前向运动精子百分比差的相关性无统计学意义(P>0.05)。再次生育时精液周期妊娠率为20.9%,与同期首次生育的周期妊娠率21.49%相比,差异无统计学意义(P>0.05)。结论再次生育时精液质量与首次生育时比较略下降,提示精液冷冻保存时间的延长对精子活力有影响,但冷冻保存时间的长短与对精液质量影响大小的相关性无统计学意义。     

Ⅲ型前列腺炎患者精液参数、锌浓度及抗菌活性的变化

目的:探讨Ⅲ型前列腺炎(CP/CPPS)患者精液常规参数、锌浓度及抗菌活性的关系。方法:对60例CP/CPPS患者和20例健康男性进行精液常规参数、锌浓度及抗菌活性的检测。结果:CP/CPPS患者精液液化时间、精子活力、精浆抗菌活性及精浆锌离子浓度与对照组相比,差异有显著性(P均<0.01)。CP/CPPS患者精子活力与精浆锌离子浓度间有显著相关性(r=0.272,P=0.015)。精浆抗菌活性与精浆锌离子浓度间有显著相关性(r=0.449,P<0.01)。结论:CP/CPPS患者精液液化时间延长,精子活力下降,精浆锌浓度和抗菌活性降低。精浆抗菌活性与精浆锌浓度、精子活力间有显著相关性。     

Free radical scavenger effect of rebamipide in sperm processing and cryopreservation

Aim: To study the effect of rebamipide added to semen samples and cryoprotectant on reactive oxygen species (ROS) production. Methods: Semen samples from 30 fertile and healthy volunteers were collected by masturbation after 2 days - 3 days of abstinence. After liquefaction, the specimens were diluted with sperm wash media to a uniform density of 20×106/mL. Rebamipide was added to semen samples and cryoprotectant to a final concentration of 10 μmol/L, 30 μmol/L, 100 μmol/L or 300 μmol/L. Specimens were incubated at 37 ℃ in a 0.5 % CO2 incubator for 1 h or cryopreserved at -196 ℃ LN2 for 3 days. The sperm motility and viability and the levels of ROS and lipid peroxidation of sperm membrance were assessed before and after incubation and cryopreservation by means of computer assisted semen analyzer, eosin-nigrosin stain, chemiluminescence and thiobarbituric acid assay, respectively. Results: The sperm motility was significantly increased after incubation with 100 μmol/L and 300 μmol/L rebamipide (P     

Evaluation of the cryoprotective effect of seminal plasma on llama (Lama glama) spermatozoa

In South American camelids, sperm survival is low after thawing and poor results are obtained when artificial insemination is performed with cryopreserved semen. The aim of this study was to evaluate the effect of different percentages (10% and 50%) of seminal plasma added prior to the process of cryopreservation and also to evaluate the absence of seminal plasma on llama sperm survival after freezing and thawing. A total of 15 ejaculates from five adult llama males (n = 5; r = 3) were evaluated. A significant decrease in sperm motility, viability, membrane function and intact acrosomes was observed in thawed samples (0%, 10% and 50%) when compared to raw semen. Neither morphology nor chromatin condensation was altered in all thawed samples (p > 0.05), but a significant increase (p < 0.05) in the percentage of spermatozoa with fragmented DNA was observed after thawing all samples compared to raw semen. Higher percentages of total and progressive sperm motility were observed when 0% and 10% of seminal plasma were used compared to 50%. However, no statistical differences were established for sperm viability, membrane function, morphology, acrosome status and DNA quality between thawed treatments. To conclude, neither of the percentages of seminal plasma used showed superiority nor cryoprotective effect on llama sperm survival.     

Incubation of frozen-thawed llama sperm with seminal plasma

Seminal plasma is intimately connected to sperm physiology and particularly in South American Camelids, has demonstrated to be involved in multiple physiological reproductive events. Different percentages of seminal plasma (0%, 10% and 50%) were added to thawed llama semen samples with the objective of evaluating the interaction with cryopreserved sperm over time (0, 1.5 and 3 hr at 37°C). A total of 20 ejaculates from five adult llama males (n = 5; r = 4) were evaluated. A significant decrease in sperm motility, membrane function and live sperm was observed in all thawed samples (0%, 10% and 50%) at 0 hr when compared to raw semen. Neither morphology nor chromatin condensation was altered in all thawed samples (p > .05), but a significant increase in the percentage of spermatozoa with fragmented DNA was observed after thawing all samples versus raw semen. When evaluating thawed samples over time, a significant decrease of motility and membrane function was observed, while the percentages of total live sperm were preserved over the 3 hr of incubation in all final concentrations evaluated. To conclude, the addition of 10% or 50% of seminal plasma was incapable of preserving motility or membrane function of frozen-thawed llama sperm during 3 hr of incubation.     

Reactive oxygen species generation by seminal cells during cryopreservation

Objectives. To test the hypothesis that conventionally used procedures for semen cryopreservation may cause an increase in the production of reactive oxygen species (ROS) by sperm or by seminal leukocytes, which may contribute to poor sperm function following cryopreservation.Methods. Eighteen semen specimens with normal parameters from healthy male donors 22 to 40 years of age were each divided into two portions. The first portion was combined 1:1 with Test Yolk Buffer-Glycerol Freezing Medium and was frozen by gradual cooling into liquid nitrogen (−196°C). The second portion was washed and the cells were resuspended in Sperm Washing Medium (SWM) and incubated at room temperature to serve as controls. After a period of treatment, frozen samples were thawed and semen cells were washed and resuspended in SWM. ROS generation by semen cells from each treatment group was measured on a luminometer. Sperm motility, sperm viability, and sperm membrane integrity were also measured in both control and freeze-thaw samples. To further assess ROS generation by semen cells during the cooling process, aliquots of washed semen cells and purified polymorphonuclear leukocytes (PMNs) were incubated separately at different temperature conditions (37°C, 22°C, 4°C, and −20°C). ROS activity in each treatment group was measured and compared with each other.Results. In both semen cells and PMNs, ROS activity increased significantly during the cooling process. The highest ROS levels were recorded in both groups when cooled to 4°C. The ROS levels were extremely low in samples cooled to −20°C and in freeze-thaw samples, probably due to marked loss of cell viability.Conclusions. Gradual reduction of temperature during the process of semen cryopreservation can cause a significant ROS generation by semen cells. ROS is particularly elevated during cooling if the semen sample is contaminated by more than 0.5 × 10⁶ leukocytes. Removal of leukocytes from semen samples or treatment with antioxidants prior to cryopreservation may improve sperm viability and function.     

Effect of cysteine and glutamine added to extender on post‐thaw sperm functional parameters of buffalo bull

Amino acids seem to be crucial components for semen freezing extender due to antioxidant properties. Therefore, this study aimed to assess motility parameters, membrane integrity, intracellular reactive oxygen species (ROS), mitochondrial membrane potential (MMP) and DNA damage to detect the optimum concentrations of cysteine and glutamine for buffalo semen cryopreservation. Twenty ejaculates of four buffalo bulls were diluted in tris‐egg yolk extender and divided into seven equal groups consisting of cysteine (5, 7.5 and 10 mmol), glutamine (10, 15 and 20 mmol) and no additive. Supplementation of 5 and 7.5 mmol cysteine and 15 mmol glutamine in cryopreservation extender significantly increased post‐thaw motility and plasma membrane integrity of spermatozoa with significant reduction in intracellular ROS when compared with control groups (P < 0.05). Cysteine at 7.5 mmol concentration elevated progressive motility and MMP, compared with control (P < 0.05). No significant differences were observed for motion patterns and DNA damage of frozen–thawed buffalo spermatozoa in extender containing amino acids. The findings of this study showed that supplementation of 7.5 mmol cysteine and 15 mmol glutamine in semen cryopreservation extender has more potential to decrease intracellular ROS, and subsequently elevate motility and membrane integrity of buffalo frozen–thawed spermatozoa.     

异黄酮辅剂对解冻精子特征的影响

本研究评价了使用异黄酮作为辅剂的解冻剂对解冻精子精液参数的影响。我们分析了辅剂在解冻过程中对精子活力、精子获能能力（膜脂功能紊乱）、活性氧生成、精子核浓缩及DNA损害的影响。根据初步的数据,辅剂可能会改善解冻过程,减少细胞损伤。我们已经证实异黄酮在精子解冻过程中有抗氧化作用、能够减少活性氧的生成,有利于精子活力轻微提高,降低膜脂功能紊乱和由冷冻而引起的DNA破坏。结果显示异黄酮作为辅剂有助于提高精子功能,这对于辅助生育中使用解冻精子很有意义。我们的发现有必要进一步研究来确证并评价临床应用的可能性。     

Reduced penetration of zona-free hamster ova by cryopreserved human spermatozoa

The effect of cryopreservation on human sperm fertilizing potential was assessed by using the human sperm penetration into zona-free hamster ovum test. Semen samples from 12 fertile men were compared before and after cryopreservation for motility, sperm penetration rate, and number of sperm cells incorporated per oocyte. In fresh samples sperm concentration was 102 +/- 51 X 10(6) cells/ml, motility 66 +/- 14%, penetration rate 77.8 +/- 19%, and sperm incorporation 4.3 +/- 3.9 sperm per ovum. Frozen-thawed sperm cells showed a marked reduction of 61 +/- 21% (p less than 0.001) in motility. Penetration rate was reduced by 53 +/- 34% (p less than 0.01), and sperm incorporation dropped by 50 +/- 28% (p less than 0.05). Despite this substantial reduction in all three parameters, 75% of the samples maintained a penetration rate exceeding 14%, which is the lower limit for fertile semen. For the individual subject the decrease in sperm motility did not reflect actual fertility potential as expressed by its ability to penetrate zona-free hamster ova. These findings are related to morphological and biochemical changes in frozen-thawed semen and apparently are correlated with the decrease in pregnancy rates after cryopreservation. This test may be a valuable supplement to routine microscopic semen analysis for semen cryopreservation candidates.     

精子冻存技术及上游法精子处理技术对精子DNA完整性的影响

目的通过对冷冻前后及精子处理前后精子DNA完整性的比较,探讨冷冻技术、冷冻时间及上游法精子处理技术对精子DNA完整性的影响。方法（1）精液常规检测正常的患者30例,手淫法取精,精液液化混匀后分4份,分别用于精子染色质扩散（SCD）实验检测精子DNA完整性、上游法处理精液、以及两组冻存实验（不加保护剂直接冻存的为冻存1组;添加蛋黄葡萄糖保护剂冻存的为冻存2组）;（2）上游法处理后的精液一部分用于检测精子动力和形态,一部分用于精子DNA完整性检测;（3）冻存1组分别于冻存第7天和第90天解冻,SCD实验检测精子DNA完整性;（4）冻存2组分别于第7天和第90天解冻,0．1ml用于精子DNA完整性检测,剩余精液应用上游法处理,检测上游处理前后精子DNA的完整性。结果（1）冻存1组中,冻存90d后解冻的精子DNA损伤率[（25．6土7．3）％]显著高于冻存7d者[（22．4±7．4）％]（P〈0．05）,且均显著高于新鲜精液的精子DNA损伤率[（20．6±7．3）％]（P〈O．05）;冻存2组中,冻存90d后精子DNA损伤率显著高于冻存7d者[（25．9±7．2）％VS．（23．6土7．8）％]（P〈O．05）,且均显著高于新鲜精液（P〈0．05）;而冻存7d和90d后,两个冻存组间比较,精子DNA损伤率均无显著差异（P〉0．05）。（2）新鲜精液经上游法处理后,精子DNA损伤率由处理前的（20．6±7．3）％降为（6．4±2．5）％（P〈O．05）;冻存2组中精液冻存7d和90d后复苏上游法处理后,精子DNA损伤率较未经上游法处理者均显著降低[分别为（9．38±2．8）％VS．（23．6±7．8）％和（9．7±2．6）％VS．（25．9±7．2）％]（P％0．05）。结论冻存对精子DNA有损伤,冻存时间对于精子DNA完整性有影响。不添加保护剂直接冻存和添加保护剂对精子DNA完整性的影响无显著差异。不论是新鲜精液还是冻存复苏精液,上游法处理并不会增加精子DNA的损伤,且有利于筛选出具有更好DNA完整性的精子。     

Effect of pentoxifylline on motility and membrane integrity of cryopreserved human spermatozoa

The purpose of this study was to examine the effects of pentoxifylline used before and after semen cryopreservation-thawing on sperm motility and membrane integrity. Twenty-four semen samples were split into four equal aliquots. Aliquots were incubated at 37 degrees C for 30 min, followed by cryopreservation with TEST-yolk freezing medium using slow programmable freezing protocol. After 2 weeks the sperm samples were thawed, washed twice in Quinn's Sperm Washing Medium (modified HTF with 5.0 mg/mL Human Albumin) and incubated at 37 degrees C for 30 min. Aliquots were treated by adding 3 mmol/L pentoxifylline to: (1) fresh sperm samples during incubation period prior to cryopreservation, (2) sperm samples as a supplement to the cryoprotectant prior to cryopreservation, and (3) thawed sperm samples during incubation period. One aliquot received no treatment (control group). The addition of 3 mmol/L pentoxifylline to fresh semen during incubation period prior to cryopreservation significantly decreased progressive and total motility compared with controls. However, the addition of 3 mmol/L pentoxifylline to cryopreserved semen after thawing significantly increased progressive and total motility compared with controls. After post-thaw, no differences in motion characteristics between sperm samples treated by adding 3 mmol/L pentoxifylline as a supplement to the cryoprotectant and control groups were observed. Post-thaw hypoosmotic swelling (HOS) test scores did not improve with the addition of pentoxifylline compared with the control group. It is concluded that pentoxifylline enhanced post-thaw motility of cryopreserved human spermatozoa when added after thawing. No improvement was found by freezing sperm with pentoxifylline.     

Damage to chromosomes and DNA of rhesus monkey sperm following cryopreservation

Fresh and frozen-thawed rhesus monkey sperm were analyzed for DNA damage using the comet assay and for chromosome damage by cytogenetic analysis after intracytoplasmic sperm injection (ICSI) into mouse oocytes. The percentage of fresh sperm with damaged DNA in ejaculated semen was 0 to 2.7% (n = 5). Conventional cryopreservation and storage in liquid nitrogen caused DNA damage in 25.3% to 43.7% of sperm; when sperm were frozen without cryoprotectants, 52.7% to 92.0% of thawed sperm had DNA damage. However, no significant difference in chromosome damage was found between fresh sperm and frozen-thawed sperm when motile sperm were selected for ICSI. The percentage of sperm with abnormal karyotypes ranged from 0 to 8.3%. The most common structural chromosomal abnormalities in fresh motile sperm and frozen-thawed motile sperm were chromosome breaks or fragments. Our findings suggest that genetically competent frozen-thawed macaque sperm can be selected for fertilization by using only motile sperm for ICSI.