Chymotrypsin effects on the determination of sperm parameters and seminal biochemistry markers.

BACKGROUND: Few reports of the effects of treatment with chymotrypsin on the determination of sperm parameters and seminal biochemistry markers are documented. METHODS: Sperm parameters of 63 liquefied and 27 non-liquefied samples, untreated or treated with chymotrypsin, were evaluated using computer-assisted semen analysis. In addition, biochemistry markers such as gamma-glutamyltranspeptidase, alpha-glucosidase and fructose in 50 liquefied and 39 non-liquefied samples, untreated or treated with chymotrypsin, were determined. RESULTS: Treatment with chymotrypsin had no effect on sperm concentration, motility, motility a and b, straightness, curvilinear velocity, straight line velocity, average path velocity and beat cross frequency in both liquefied and non-liquefied semen. However, linearity (p=0.025) decreased and the amplitude of the lateral head (p=0.029) increased significantly in non-liquefied semen after treatment with chymotrypsin. The levels of gamma-glutamyltranspeptidase, alpha-glucosidase and fructose in seminal plasma were unaffected by chymotrypsin, regardless of liquefaction status. CONCLUSIONS: Chymotrypsin had no effects on the detection of sperm parameters and biochemistry markers, and could be used to treat non-liquefied samples before semen analysis in the andrology laboratory.     

Prevention of in vitro lipolysis by tetrahydrolipstatin

BACKGROUND: Metabolic effects of free fatty acids (FFAs) frequently are tested using combined infusion of triglycerides and heparin, which stimulates lipolysis in vivo. Ongoing in vitro lipolysis, however, probably produces falsely high plasma FFA concentrations under these conditions. Therefore, this study aims to assess the efficacy of tetrahydrolipstatin (THL) in inhibiting plasma lipolytic activity and to improve plasma FFA determination. METHODS: Plasma concentrations of FFAs and glycerol were measured in five healthy subjects in the presence and absence of THL. Blood was drawn at baseline, during infusion of a triglyceride emulsion (1.5 mL/min), and during infusion of triglycerides plus heparin (0.2 IU. kg(-1). min(-1)). In addition, the effects of storage temperature of the samples were analyzed. RESULTS: In samples frozen immediately after collection, plasma FFAs were 28% lower in the presence of THL than in its absence (P = 0.008). When THL-free plasma was incubated for 3 h on ice or at room temperature, plasma FFAs were 22% (P = 0.02) and 91% (P = 0.0004) higher, respectively, than in samples frozen immediately. The addition of THL blunted temperature-dependent in vitro lipolysis by 88% (P<0.01) and 89% (P <0.001) after incubation on ice and at room temperature, respectively. Changes in plasma glycerol concentrations exhibited similar behavior. CONCLUSIONS: THL, which is safe and easy to handle, is a potent inhibitor of in vitro lipolysis and could, therefore, be added to blood samples drawn during triglyceride/heparin infusions to allow more accurate determination of plasma FFA concentrations.     

解脲支原体感染对精液中精浆生化成分及精子顶体完整性的影响

目的探讨解脲支原体(Uu)感染对精液中精浆生化成分α-葡萄糖苷酶(-αGLU)、酸性磷酸酶(ACP)、果糖(Fru)、锌(Zn)及精子顶体完整性的影响。方法 Uu检测使用Uu培养基进行培养。精浆生化项目按操作说明书进行操作。采用姬-瑞染色法分析精子顶体完整率。结果 Uu感染者中精液中精浆的部分生化成分及精子顶体完整率出现明显改变,比较差异有统计学意义(P<0.05)。结论 Uu感染对精液中精浆生化成分a-GLU,ACP的结果及精子顶体完整率有着显著影响,对Fru及Zn含量无显著影响。     

精浆天门冬氨酸氨基转移酶及其线粒体同工酶检测与精子膜功能完整性的关系

目的对精浆天门冬氨酸氨基转移酶(AST)及其线粒体同工酶(m-AST)的活性进行检测,并分析AST和m-AST活性与精子膜功能完整性的相关性。方法 122例精液标本,分别检测精浆AST和m-AST活性,用低渗肿胀-伊红Y结合试验(HOS-EY)检测精子头-尾膜完整性,用琥珀酸脱氢酶(SDH)染色法检测精子线粒体SDH,同时分析AST和m-AST活性与精子膜功能完整性的相关性。结果精浆AST与m-AST的活性分别为(238±125)U/L和(147±79)U/L,两者呈明显正相关性(r=0.740,P=0.000)。AST和m-AST活性均与(Ⅰ+Ⅱ+Ⅲ)型精子呈明显正相关性(r=0.443,P=0.013;r=0.691,P=0.000)。AST和m-AST活性均与Ⅳ型精子呈明显负相关性(r=-0.439,P=0.013;r=-0.689,P=0.000)。AST活性与精子SDH阳性率无明显相关性(r=-0.187,P=0.313),而m-AST活性与精子SDH阳性率呈明显负相关性(r=-0.471,P=0.007)。结论精浆AST和m-AST活性与精子膜功能完整性具有相关性,而m-AST活性检测更适合评价精子膜受损程度以及精子线粒体受损状况。     

Release of anandamide from blood cells.

BACKGROUND: Endogenous ligands of cannabinoid receptors (endocannabinoids), in particular anandamide (arachidonylethanolamide), have been recognized as being of crucial importance in a variety of physiological functions. Plasma concentrations of anandamide have been measured in a number of investigations; however, discrepant data on "normal" anandamide plasma concentrations were reported. Since this might be caused by pre-analytical variables, we investigated the impact of different sample handling conditions on measured plasma anandamide concentrations. METHODS: Blood samples were taken from healthy volunteers in EDTA- or heparin-containing tubes; whole blood samples were kept at +4 degrees C, room temperature, or 37 degrees C, respectively, for up to 120 min before obtaining plasma by centrifugation. Plasma anandamide concentrations were measured by an isotope-dilution liquid chromatography tandem mass spectrometry (LC-MS/MS) method. RESULTS: A marked time- and temperature-dependent increase in plasma anandamide concentrations ex vivo was observed in both EDTA- and heparin-containing tubes. Mean anandamide concentrations approximately doubled when EDTA samples were kept at 4 degrees C for 60 min before centrifugation [immediately centrifuged, 1.3 microg/L (SD 0.3 microg/L); 2.8 microg/L (SD 0.5 microg/L) after storage for 60 min; n=12). After storage of heparinized whole-blood samples for 120 min at 37 degrees C, a mean plasma anandamide concentration of 11.9 microg/L (SD 1.8 microg/L) was found. In cell-free plasma, no increase in anandamide concentrations was found. CONCLUSION: Anandamide is released from blood cells ex vivo at a very high rate; therefore, strictly standardized pre-analytical protocols have to be applied for plasma anandamide determination.     

身体质量指数与精液质量及精浆生化指标的相关性研究

目的探讨身体质量指数(BMI)对不育男性精液质量及精浆生化指标的影响及其之间的相关性。方法选择于汉中市中心医院泌尿外科就诊的298例不育男性为研究对象,按照BMI将其分为体重正常组(18.5~23.9 kg/m2),超重组(24.0~27.9 kg/m2)和肥胖组(≥28 kg/m2)。对所有研究对象进行精液常规和精子形态学检查,离心后的精浆成分进行生化指标检测。比较三组间的精液参数及精浆生化指标。结果298例研究对象的平均BMI为(23.7±3.3)kg/m2,其中包括152例正常组占51.0%,110例超重组占36.9%,36例肥胖组占12.1%。三组间的精液pH、精液量、精子密度、精子总活力、前向运动精子率、精浆柠檬酸、精浆果糖、精浆锌及精浆酸性磷酸酶比较,差异均无统计学差异(P>0.05);三组间的正常精子形态率比较,差异具有统计学意义(χ2=16.617,P=0.000)。Mann-Whitney U检验显示肥胖组与正常组,肥胖组与超重组的正常精子形态率比较,差异均具有统计学意义(分别为U=17,Z=-3.968,P=0.000;U=29.5,Z=-2.755,P=0.006);而超重组与正常组的正常精子形态率比较,差异无统计学意义(U=214,Z=-1.609,P=0.108)。Spearman相关分析显示,正常精子形态率与BMI分组之间存在负相关(rs=-0.489,P=0.000),其他精液参数与BMI分组之间均不存在相关关系(P>0.05)。结论随着BMI的增加正常形态精子比例会降低,表明体重在一定程度上影响男性生育能力。     

Superoxide dismutase activities of spermatozoa and seminal plasma are not correlated with male infertility

Abnormal reactive oxygen species (ROS) production is associated with defective sperm function. Superoxide dismutase (SOD) is related with the scavenging of seminal ROS. We aimed to determine the effect of SOD activities of spermatozoa and seminal plasma on sperm quality. Semen samples from infertile couples who consented to the analyses were divided into two groups: 1) normospermia (n = 20); and 2) oligoasthenozoospermia (n = 31). The SOD activities of the spermatozoa and seminal plasma were measured by determining the inhibition of pyrogallol autoxidation. The SOD activities of spermatozoa and seminal plasma in both groups were compared. The relationships between the SOD activities and the sperm qualities were determined. We noted that SOD activities of sperm/seminal plasma in both groups were nonsignificantly different (group 1 vs. 2 = 0.77 +/- 0.33/0.84 +/- 0.40 U/mg protein for sperm, and 0.66 +/- and 0.36/0.83 +/- 0.47 U/ml for seminal plasma). SOD activities of sperm/seminal plasma were positively but nonsignificantly correlated with the sperm motility (SOD of sperm = 0.0008 x motility + 0.67; SOD of seminal plasma = 0.0006 x motility + 0.81) and concentration (SOD of sperm = 0.0006 x concentration + 0.67; SOD of seminal plasma = 0.0021 x concentration + 0.73). We concluded that SOD activities of sperm and seminal plasma were nonsignificantly correlated with the seminal quality. It appears that the SOD survey is not a useful tool for determining sperm fertilization potential.     

Rapid separation of serum does not avoid artificially higher matrix metalloproteinase (MMP)-9 levels in serum versus plasma

OBJECTIVES: To examine whether the time between blood drawing and centrifugation (TBDC) affects the levels of matrix metalloproteinase (MMP)-9 and MMP-2 levels in serum and in plasma samples, and to assess whether there is correlation between MMP-9 and MMP-2 levels in serum and plasma samples. DESIGN AND METHODS: Serum and plasma samples (N=8) were separated from venous blood collected into citrate, heparin, and EDTA tubes, which were either centrifuged immediately or after 5, 10, 20, or 30 min after blood drawing. We assessed the correlation between MMP-9/MMP-2 in serum and citrate, heparin, and plasma samples (N=20), which were assayed for gelatine zymography of MMP-2 and MMP-9. RESULTS: MMPs are released by platelets or leukocytes during platelet activation or sampling process, thus leading to artificially higher MMP-9 levels in serum compared with citrate, heparin, or EDTA plasma samples, independently of TBDC. Citrate and heparin plasma samples had the lowest Pro-MMP-9 and MMP-9 levels, which correlated with each other. Pro-MMP-9 levels in serum correlated with Pro-MMP-9 levels in EDTA or citrate plasma, but not with heparin plasma. While no significant correlations were found between MMP-9 levels in serum and those found in plasma samples, the total MMP-9 levels (Pro-MMP-9+MMP-9) in serum and in plasma samples correlated with each other. No significant differences were found in pro-MMP-2 levels. CONCLUSIONS: These results suggest that the circulating levels of MMP-9 should be assessed in citrate or heparin plasma samples, but not in serum samples because of artificially higher MMP-9 levels in serum, independently of TBDC, and because they do not correlate with the MMP-9 levels in plasma samples.     

血浆稀释法和高速离心法消除凝血项目检测标本脂肪血干扰的实验研究

目的 研究脂肪血标本对凝血结果的干扰,并探讨血浆稀释法和高速离心法消除脂肪血标本的效果对比研究.方法 收集2017年1月～2019年12月期间健康体检者血浆标本100份(正常对照组),用脂肪乳配制成轻度脂肪血组(TG为3.955±1.053mmol/L)、中度脂肪血组(TG为8.020±3.126mmol/L)及重度脂...     

精浆8-OHdG 和GSTs 水平与男性不育的相关性研究

目的 探讨精浆8-羟基脱氧鸟苷(8-hydroxydeoxyguanosine, 8-OHdG)和谷胱甘肽硫转移酶(glutathioneS-transferases,GSTs)水平与男性不育疾病的相关性。方法 收集2017年5月～2019年5月期间在陕西省咸阳市第一人民医院和渭南市蒲城县医院就诊的35例不育男性患者的精液标本进行分析。同时收集婚后已生育的26例健康男性的精液标本作为对照组。分析两组精液质量、精浆8-OHdG和GSTs水平、血清睾酮(testosterone,T),卵泡刺激素(follicle stimulating hormone,FSH)及黄体生成素(luteinizing hormone,LH)水平的变化及其相关性。精浆8-OHdG和GSTs水平采用酶联免疫吸附法测定。精液质量采用伟力 CASA 900系统进行分析。结果 对照组的精浆8-OHdG(pg/ml)和GSTs(U/ml)水平分别为87.13±26.30和25.34±3.09,不育组的精浆8-OHdG(pg/ml)和GSTs(U/ml)水平分别为156.37±52.31和12.71±1.25。与对照组比较,不育组精浆8-OHdG水平显著增高,而GSTs水平则显著降低,差异均有统计学意义(t=26.43～45.21,P=0.000)。对照组的精液总量(ml)、精子密度(×10⁶/ml)、精子活力(%)和精子畸形率(%)分别为3.16±0.28,83.23±22.28, 62.27±5.13和7.23±2.39。不育组的精液总量(ml)、精子密度(×10⁶/ml),精子活力(%)和精子畸形率(%)分别为3.02±0.25,5.32±3.90,10.23±2.18和49.56±7.29。与对照组比较,不育组的精子密度及精子活力显著降低,而精子畸形率则显著增高,差异有统计学意义(t=43.64～69.26,P=0.000)。不育组和对照组的精液总量比较,差异无统计学意义(t=0.399,P=0.732)。对照组的血清T(nmol/ml),FSH(mIu/ml)及LH(mIu/ml)水平分别为19.23±5.38,5.83±1.37,5.19±2.24 。不育组的血清T(nmol/ml),FSH(mIu/ml)及LH(mIu/ml)水平分别为7.97±3.62, 19.90±3.36和15.53±5.13。与对照组比较,不育组的FSH及LH水平显著增高,T水平则显著降低,差异均有统计学意义(t=17.92～31.23,P=0.000)。精浆8-OHdG水平与精子密度、精子活力和血清T水平有负相关性,而与精子畸形率、血清FSH及LH水平有正相关性(r=-0.823,-0.819,-0.798,0.767,0.782,0.807,均P<0.01)。精浆GSTs水平与精子密度、精子活力和T水平有正相关性,而与精子畸形率、血清FSH及LH水平有负相关性(r=0.857,0.842,0.819,-0.838,-0.802,-0.814,均P<0.01).结论 8-OHdG和GSTs通过调节机体的氧化应激能力影响精子质量,检测精浆8-OHdG和GSTs水平可以为男性不育疾病的诊治提供依据。     

不育患者精浆酸性磷酸酶和前列腺特异抗原含量与精子质量的关系

目的探讨不育患者精浆酸性磷酸酶（ACP）和前列腺特异抗原（PSA）含量与精子质量的关系。方法随机选择男性不育症患者122例,采用精子分析仪测定精液参数,同时用酶联免疫吸附试验（ELISA）法检测精浆中PSA水平,用磷酸苯二钠法检测精浆中ACP含量,并分析其与精子密度、活力和黏度的关系。结果精子活力异常组精浆ACP、PSA含量明显低于活力正常组,两组比较差异有统计学意义（P〈0．05）;精液黏度增高组精浆ACP、PSA含量明显低于精液黏度正常组,两组比较差异有统计学意义（P〈0．05）。精子密度正常组ACP高于密度减低组（P〈0．05）,PSA含量两组无明显差异。结论精浆ACP、PSA含量与精子质量有密切关系。     

男性不育患者精浆miR-551b水平变化及其临床价值

目的 检测和分析男性不育症患者精浆miR-551b水平变化,探讨其作为男性不育症辅助分子标志物的可能性。方法 选取2008年11月～2015年3月在南京总医院生殖医学中心和江苏省中医院男科门诊确诊的92例男性不育症患者及同期招募的34例年龄匹配正常生育男性精液标本,记录患者及对照临床资料,测定患者及对照精液参数包括精子密度、精子活率、a级精子比例、a+b级精子比例及部分精浆生化指标α-糖苷、酸性磷酸酶、肉毒碱、果糖水平。实时荧光定量PCR技术(quantitative real-time PCR,qRT-PCR)检测和比较弱精症、非梗阻性无精症患者及正常生育男性精浆中miR-551b含量变化,统计分析精浆miR-551b临床价值及与精液参数、精浆生化指标相关性。结果 qRT-PCR结果显示,正常生育组精浆miR-551b水平为20.63(9.59,37.83)fmol/L,弱精症患者为62.29(25.22,101.43)fmol/L,较正常生育组显著升高(U=297.00); 无精症患者精浆miR-551b水平为4.70(2.41,13.71)fmol/L,较正常生育组明显降低(U=356.00),差异均具有统计学意义(P<0.001)。受试者工作特征曲线(receiver operating characteristic curve,ROC)分析显示,精浆miR-551b区分弱精症、无精症患者与正常生育组的ROC曲线下面积(AUC ROC)分别为0.810(95%CI 0.718～0.902)和0.772(95%CI 0.667～0.878); 鉴别弱精症和无精症患者的AUC ROC为0.932(95%CI 0.885～0.979)。Spearman秩相关性分析显示,男性不育患者精浆miR-551b水平与精子密度(r=0.735)、精子活率(r=0.643)、a级精子比例(r=0.672)、a+b级精子比例(r=0.682)及α-糖苷(r=0.375)呈正相关,差异均具有统计学意义(均P<0.05)。逐步多元线性回归结果显示,男性不育症患者精浆miR-551b水平与精子密度呈显著独立相关(β=0.618,P<0.001,校正r²=0.368)。逻辑回归分析显示,精浆miR-551b是弱精症[OR = 24.889(95%CI 5.302～116.843),P<0.001]和无精症[OR=6.303(95%CI 1.316～30.179),P=0.021]的潜在危险因素。结论 男性不育症患者精浆miR-551b水平与正常生育男性存在明显差异,且与精子密度和活力密切相关,有潜力成为男性不育患者辅助诊断和鉴别诊断的新型分子标志物。     

不育症患者精浆弹性蛋白酶检测的临床意义

目的研究男性不育患者精浆中弹性蛋白酶的含量变化和临床意义,探讨其在诊断无症状性生殖道炎症中的作用;以及其对精子DNA完整性的保护作用的研究。方法收集140例不育症门诊患者的精浆标本（实验组）;按WHO标准80例诊断为弱精子症;60例为精液常数正常的不育症男性。所有患者都没有生殖道感染的症状,3个月前无抗菌治疗。采用ELISA双抗体夹心酶联免疫吸附法检测患者精浆弹性蛋白酶水平,20例生育男性作对照。采用硝酸还原酶法检测精浆一氧化氮水平;采用吖啶橙染色,计算单链DNA精子比例,对精子DNA完整性进行评估。结果1、140例不育男性患者（实验组）精浆中的弹性蛋白酶、一氧化氮（NO）浓度、精子单链DNA百分比明显高于生育男性（对照组）（P〈0．001）。2、弹性蛋白酶浓度与患者年龄（r=0．255,P〈0．01）及精液中白细胞数（r=0．569,P〈0．01）有正相关关系。3、弹性蛋白酶浓度与精液量（r=0．537,P〈0．01）及精子单链DNA比率（r=0．436,P〈0．01）呈负相关关系;与精浆NO浓度无相关关系（r=0．083,P=0．331）。结论精浆中粒细胞弹性蛋白酶检测对诊断无症状性生殖道炎症是一种可靠的筛查试验,另外,弹性蛋白酶可能对精子DNA有保护性作用。     

精浆各微量元素含量对精子形态的影响

目的 通过观察分析精子形态,检测其精浆微量元素,探讨精浆各微量元素含量对精子形态的影响.方法 采集136例男性不育症患者的新鲜精液,置37 ℃温箱待液化后,先用计算机辅助精液分析系统进行分析,再取有精子的精液涂片做改良巴氏法染色镜检分析,然后精液离心取上清液检测各微量元素含量.结果 精子畸形率随精浆中钙、铜、铅、镉含量的增多及镁、锌含量减少而增高,相关分析显示呈不同程度的正负相关,与健康对照组比较差异有统计学意义(P<0.05).结论 精浆微量元素的含量增多或减少均影响精子的形态质量,而且有害元素铅、镉对精子损伤更大,应引起临床的高度重视.     

精浆和血清抗苗勒管激素与精液参数的相关性研究

目的探讨精浆和血清抗苗勒管激素(AMH)水平与男性精子数量和活力的相关性。方法选取到广东省中山市博爱医院生殖门诊就诊的、因女性原因不孕的健康男性215例,检测精浆、血清AMH及精液参数(精子的密度、活率、活力及畸形率),测定血清性激素6项。分别以精浆和血清AMH为因变量,采用多重线性回归模型探讨其与精液参数和性激素水平的定量关系。结果 215例研究对象中,总精浆AMH中位数为0.47,四分位数为0.05~3.09pmol/次射精。血清AMH中位数为53.07,四分位数为32.32~72.20pmol/L。经过多重线性回归分析,在矫正年龄和体质量指数后,精浆AMH与精子总数、精液浓度、前向精子活动力、总精子活动力、血清抑制素B呈正相关(P0.05);与精子形态和其他血清性激素相关性比较,差异无统计学意义(P0.05);血清AMH与血清促卵泡激素呈负相关,与血清抑制素B呈正相关(P0.05);与精浆各参数和其他血清性激素相关性比较,差异无统计学意义(P0.05)。结论精浆AMH个体差异大,与精液浓度、精子总数、精子活力呈正相关,尚未发现血清AMH与其相关。     

血浆与血清同型半胱氨酸在不同检测条件下比较及稳定性研究

目的分析同型半胱氨酸(Hcy)水平在血浆与血清中的差异及放置不同时间检测的稳定性。方法分别以EDTA-K2抗凝管和分离胶管收集42例健康体检人员血液,于即刻及放置3h后分离血浆及血清。选EDTA-K2抗凝管立即离心分离血浆后于室温放置1h、3h、6h及2-8℃24h;分离胶管放置30min待血液凝固后离心分离血清于室温放置1h、3h、6h及2-8℃24h,使用直接化学发光法检测同型半胱氨酸浓度。结果分离胶管取血放置30min后离心分离血清同型半胱氨酸浓度较即刻分离的血浆同型半胱氨酸浓度高13.24%,结果差异有统计学意义(P<0.05);取血放置3h后离心检测血清或血浆同型半胱氨酸浓度明显高于取血后即刻离心检测的同型半胱氨酸浓度,两者相差12.47%和12.56%,结果差异有统计学意义(P<0.05)。分离后血浆与血清在室温放置1h、3h、6h及2-8℃24h检测同型半胱氨酸浓度,结果差异均无统计学意义(P>0.05)。结论血清同型半胱氨酸水平明显高于血浆,分离血清或血浆前标本放置时间对检测同型半胱氨酸浓度有影响,分离后血浆或血清在2-8℃保存,24h内同型半胱氨酸检测结果差异无统计学意义。在临床工作中,应尽可能快速分离血浆标本进行同型半胱氨酸检测或分别设立血浆与血清同型半胱氨酸浓度的正常参考范围。     

High-performance liquid chromatographic detection of lipid peroxidation in human seminal plasma and its application to male infertility

BACKGROUND: A simple and reliable high-performance liquid chromatographic (HPLC) method has been developed and validated for the analysis of malondialdehyde (MDA) in human seminal plasma. METHODS: After human seminal plasma is hydrolyzed, MDA is reacted with thiobarbituric acid (TBA) to form MDA(TBA)(2), a red-colored adduct with maximum absorbance at 532 nm. HPLC separation of the adduct in human seminal plasma was performed on a Lichrospher C(18) column. RESULTS: A mobile phase composed of 0.025 mol/l KH(2)PO(4) (pH 6.2)--methanol in the ratio 58:42 (v/v) was found to be the most suitable for this separation. Under the chromatographic conditions described, the MDA-TBA adduct had a retention time of approximately 4 min and good separation and detectability of MDA in human seminal plasma sample was obtained. The method proved to be linear calibration in the range of MDA from 0.10 to 2.50 micromol/l. The relative standard deviations of within- and between-assay for MDA analysis were 3.1% and 3.8%, respectively. The average recovery was 90.0-98.8% for the human seminal plasma samples. The method has been successfully applied to the study of the lipid peroxidation levels in the seminal plasma of male infertility. Semen samples were obtained from healthy volunteers and infertile males. Ejaculates were classified into studied subgroups and defined as: obstructive azoospermia, non-obstructive azoospermia, oligozoospermia, asthenozoospermia, oligoasthenozoospermia and oligoasthenoteratozoospermia. With the exception of obstructive azoospermic group, MDA concentrations of seminal plasma in control group had very significant difference with those in other infertile groups (P < 0.01). CONCLUSIONS: This indicated that lipid peroxidation could be harmful to male sperm and reproductive system, which may lead to male infertility.     

禁欲时间对精子参数及精浆生化指标的影响

目的 探讨禁欲时间对精子参数及精浆生化指标的影响.方法 采用精子形态检测系统下人工修正方法进行精子形态分析.采用精子质量检测系统进行精子密度、活力分析.精浆果糖含量、中性a糖苷酶、精浆锌、酸性磷酸酶等采用分光光度比色法测定.采用DTNB改进法检测精浆肉毒碱含量.前列腺特异性抗原(PSA)采用试剂盒进行检测.根据禁欲时间分为3组:G1(禁欲1～3d)组、G2(禁欲4～5d)组和G3(禁欲6d以上)组.结果G2组精子密度[(70.64±63.79)×106]显著高于G1组[(57.40±45.36)×106,P＜0.01],G3组精子密度[(77.00±65.43)×106]显著高于G1组[(57.40±45.36)×106]和G2组[(70.64±63.79)×106,P＜0.01];而G3组精子活力[(36.30±21.46)%]和形态正常精子百分率[(17.00±9.86)%]显著低于G1组[(40.47±20.60)%,(18.32±9.83)%,均P＜0.01].G3组果糖含量[(20.86±15.54)μmol/1次射精]显著低于G1组和G2组[(26.40±16.53)、(23.45±18.08)μmol/1次射精,P＜0.01,P＜0.05],而G3组精浆中性a-糖苷酶[(47.14±33.61)mU/1次射精]、肉毒碱[(28.31±21.87)mmol/L]、锌含量[(2.67±1.47)mmol/L]均显著高于G1组[(33.67±24.14)mU/1次射精,(20.78±16.04)mmol/L,(2.21±1.01)mmol/L]和G2组[(42.05±30.63)mU/1次射精,(24.58±19.21)mmol/L,(2.07±1.01)mmol/L](P＜0.01,P＜0.05).结论 禁欲时间影响精子参数和精浆生化指标.     

Usefulness of a simple photometric determination of chymotrypsin activity in stools — results of a multicentre study

The usefulness of a new photometric test for the determination of chymotrypsin activity in stools was evaluated in a multicentre study. By release of the enzyme from stool particles with a cationic detergent solution after, in most cases, 3 min of homogenization, a photometric measurement of the enzyme activity is possible both in the clear supernatant after centrifugation and in the diluted stool homogenate. The precision of the activity measurement in stool samples with pathologically lowered and normal chymotrypsin activity is good both for in-series (CV = 2.6%, scatter 0.6-5.7%) and for day-to-day determinations (CV = 7.2%, scatter 3.9-13.9%). The results obtained by the photometric determination also exhibit a close correlation with the values measured by pH-stat titrimetry (r = 0.901). The sample-preparation system with a sample-metering chamber is easy to use and gives good agreement with determinations in which the sample metering was done by weighing out the stool (r = 0.961). The photometric test for detection of exocrine pancreatic insufficiency is easy to perform, inexpensive and does not place any undue stress on the patient.     

Increase in and clearance of cell-free plasma DNA in hemodialysis quantified by real-time PCR.

BACKGROUND: Recently cell-free plasma DNA has been described as a marker of apoptosis during hemodialysis (HD), but little is known about how different dialysis membranes may contribute to this process or whether pre-HD levels are restored afterwards. Here we evaluate the influence of the dialysis membrane on cell-free plasma DNA levels and investigate the clearance of plasma circulating DNA after HD. METHODS: Cell-free plasma DNA was measured using a real-time quantitative PCR for the beta-globin gene. Reference values for plasma DNA were established in a group of 100 healthy voluntary blood donors. Pre- and post-HD levels were also measured in 30 patients with end-stage renal disease on regular HD (52 sessions; 104 samples). The sessions lasted for 2.5-5 h. Different dialysis membranes were compared: high-flux (n=37) vs. low-flux (n=15) and polysulfone (n=42) vs. modified cellulose (n=10). To determine the time at which pre-HD levels are restored, DNA was quantified in serial plasma samples obtained from 10 of these 30 patients, just before and immediately after HD, as well as at 30, 60 and 120 min after HD. RESULTS: Reference plasma DNA values for healthy blood donors ranged from 112 to 2452 gEq/mL (median 740 gEq/mL). Cell-free plasma DNA levels significantly increased during HD (Wilcoxon test for paired samples, p<0.0001), with increases of more than four-fold observed in 75% of the patients after HD. There was no significant linear association between the length of the HD session (between 2.5 and 5 h) and the increase in cell-free plasma DNA concentration (Pearson correlation). No significant differences were observed between different types of membranes (Mann-Whitney U-test). Plasma DNA returned to pre-HD levels by 30 min after HD, regardless of the starting concentration. CONCLUSIONS: Plasma DNA levels significantly increase after a conventional 2.5-5-h HD session. Therefore, HD patients require special consideration for correct interpretation of plasma DNA concentrations. This parameter can be considered a reliable diagnostic tool for certain pathologies when measured at least 30 min after a HD session without further complications. The different dialysis membranes used in this study had no influence on cell-free plasma DNA concentrations, so the level of circulating DNA is not an appropriate marker of dialysis membrane biocompatibility.