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1.

Objectives

For individuals not on antiretroviral therapy, the risk of heterosexual transmission of HIV appears negligible when blood plasma (BP) viral loads are <1500 HIV‐1 RNA copies/mL. It is not clear whether this observation can be extrapolated to individuals on highly active antiretroviral therapy (HAART). Because of differential tissue penetration, antiretroviral drug concentrations may be sufficient to maintain an undetectable viral load in the BP yet not achieve adequate levels to suppress HIV in the genital tract. Therefore, we wanted to correlate HIV viral loads and drug concentrations in semen plasma (SP) and BP.

Methods

Thirty‐three men were included. All were on combination antiretroviral therapy with an undetectable BP viral load for at least 1 year. Blood and semen samples were collected within 2 h of each other and tested for HIV RNA by the NucliSens QT (bioMerieux, St Laurent, QC, Canada) method; drug concentrations were determined by liquid chromatography tandem mass spectrometry.

Results

Two of the 33 patients (6.1%) with BP viral loads below detection had time‐matched HIV viral loads in SP ≥700 copies/mL. Both patients were on efavirenz, the SP concentrations of which were ≤10% of the levels in BP and well below the minimal therapeutic drug monitoring target concentration required to suppress HIV.

Conclusions

Because, at least in part, of poor drug penetration into the genital tract, an undetectable HIV viral load in the BP does not guarantee an undetectable viral load in semen. In view of this, caution should be taken in concluding that patients on HAART with suppressed viraemia are sexually non‐infectious.  相似文献   
2.
Damage to the genetic component of spermatozoa seems to play the main role in a majority of cases where current approaches fail to reveal the specific cause of male infertility. In this study, we compared semen quality in men assigned to two defined groups: men from couples with unexplained infertility – idiopathic infertility (A) and young men with no experiences of infertility (B). All samples were examined by standard ejaculate analysis and sperm chromatin structure assay (SCSA). Sperm chromatin damage was significantly higher in men from group A than in those from group B. Similar results were obtained by comparison of men from group A (all men were normozoospermic) with normozoospermic men from group B. According to these results, we can suppose that chromatin disorders may be the causal factor of subfertility or infertility in some of these men. No evidence for a strong association between chromatin disorders and standard parameters of ejaculates was found. We failed to confirm a relationship between smoking and sperm quality in men from any of the investigated groups. SCSA is a method that facilitates the identification of infertile men who otherwise show normal semen variables.  相似文献   
3.
Receiver operating characteristic curves and accuracy parameters were computed for traditional sperm characteristics (concentration, motility, morphology) and the number of peroxidase negative cells, and the concentration of adenosine triphosphate (ATP) in semen from populations of fertile and infertile men, and men who achieved a pregnancy after varicocele treatment. The percentage and concentration per millilitre of spermatozoa with rapid linear progressive motility, and the ATP concentration, provided the best discrimination between fertile and treated fertile from infertile men. The misclassification rate was higher for sperm morphology, total progressive motility and viability, whereas sperm concentration and the total sperm count per ejaculate had the worst discriminating power. The number of peroxidase negative cells per 100 spermatozoa was highly specific in identifying men who achieved pregnancy after varicocele treatment. The lower limit of normality of sperm characteristics was remarkably different between fertile men and men achieving pregnancy after treatment or during infertility work-up.  相似文献   
4.
In order to evaluate the effects of pentoxifylline on sperm motility and longevity, a controlled in-vitro study was conducted on normozoospermic donor semen samples using the Cellsoft automated system for sperm motility analysis. After incubation and selection, pentoxifylline was found to improve the recovery of spermatozoa and to increase their velocity. In the subgroup of progressively motile spermatozoa, curvilinear velocity was also enhanced. It is concluded that pentoxifylline has an effect on the vigour, but not on the pattern, of sperm motion. Pentoxifylline did not improve the motility characteristics of senescent spermatozoa in normozoospermic sperm samples. Sperm survival, as shown by supra-vital staining, and motility longevity both decreased with time after pentoxifylline treatment.  相似文献   
5.
本文应用放射免疫测定的方法检测了13例输精管结扎后(平均15.3年,平均年龄50岁)的男性精浆双氢睾酮和睾酮的浓度,另取同年龄组男性13例作为对照。结果表明,精浆睾酮在结扎组(374.54p/ml)和正常对照组(315.64Pg/ml)中没有明显差异,而结扎组精浆中双氢睾酮(46.21pg/ml)却明显低子对照组(184.27pg/ml(p<0.01)。作者认为,输精管结扎对精浆DHT有长期影响,这可能是其对前列腺增生过程产生抑制作用的原因之一。  相似文献   
6.
Selecting a population of spermatozoa by the swim-up technique yields, after freezing and thawing, a population of cells that contains proportionally more spermatozoa which are morphologically normal, fewer spermatozoa with damaged tail membranes, and a greater percentage of progressively motile spermatozoa with greater velocities and amplitudes of head displacement than those obtained after freezing and thawing the same semen samples in the normal way. This pattern was found for the semen from 10 patients and five volunteers. However, the cells selected by swim-up were as susceptible to the stresses caused by freezing and thawing as unselected spermatozoa in the original semen sample, and the improvement came from the better quality of the initial sample.  相似文献   
7.
A longitudinal study of semen quality in pesticide spraying danish farmers   总被引:9,自引:0,他引:9  
It was hypothesized that occupational exposure to pesticides during a spraying season causes changes in semen quality that might be detected in a longitudinal study. We analyzed the within-person changes in semen quality and reproductive hormones across a spraying season in groups of farmers using and not using pesticides. A total of 248 men collected two semen samples (participation rate: 32%). The median sperm concentration declined significantly from the first to the second sample in both groups, but there was no statistical difference in the decline between the two groups, unadjusted or adjusted. Only minor changes were found in sperm morphology, vitality, motility, sperm chromatin denaturation (SCSA), and reproductive hormones, and the differences in changes between the two groups were nonsignificant, or, in the opposite direction to the expected. There was no relation between the changes in sperm parameters in relation to pesticide exposure variables. In conclusion, use of pesticides by Danish farmers is not a likely cause of short-term effects on semen quality and reproductive hormones.  相似文献   
8.
目的 探讨在少、弱精子症中精子形态缺陷类型及其发生率.方法 对精液常规和改良巴氏染色检查的结果进行统计学分析.结果 (1)男性不育症中畸形精子症的发生率约为75%;精子头部缺陷的发生率约为70%,各种头部缺陷中空泡头畸形的发生率占首位,约为20%.(2)少精子症患者的正常形态精子百分率的中位数约为2.97%(P=0),弱精子症患者的中位数为6.67%(P=0.003).结论 (1)精子头部缺陷是精子畸形的主要类型;(2)少、弱精子症的畸形精子比例升高;(3)精子形态缺陷分析对选择辅助助孕方式具有应用价值.  相似文献   
9.
目的:建立精浆尿酸(UA)的检测方法并探讨精浆UA水平与精液参数的相关性。方法:根据检测血清UA的方法加以改良建立检测精浆UA的方法,并观察批内变异和不同技术人员检测结果之间的差异以评价方法的可接受性。同时分析138例男性精浆UA水平与患者年龄、禁欲时间、精液量、pH、精子密度、活动率、a+b级精子百分率和正常形态精子百分率之间的相关性。结果:精浆UA检测方法的批内变异为9.16%,2位技术人员的检测结果没有显著性差异(P=0.541)。精浆UA水平与正常形态精子百分率呈正相关(r=0.350,P=0.025),与精子活动率和a+b级精子百分率有呈正相关的趋势(r=0.147和0.156,P=0.085和0.068),而与精液分析其他参数如精液量、pH、精子密度、禁欲时间以及患者年龄等无相关性。结论:通过对血清UA检测方法加以改良可以建立可接受的精浆UA检测方法。精子形态学、活动率及a+b级精子百分率可能与精浆UA水平高低有关。  相似文献   
10.
精子质量参数分析的标准化与质量控制的研究进展   总被引:4,自引:4,他引:0  
精液分析是评价男性生育能力的最基本测试。最近几年,对精液分析标准化的迫切需求已引起男科学家的广泛重视。本文对精子质量参数———精子密度、活动率和形态学分析的标准化及质量控制进行了综述。精子密度分析的关键是计数池的标准化,因此Cell-VU计数池应该是最佳的选择;精子活动率和精子形态学的分析由于主观性太强,CASA系统可能是其标准化的最终选择。精液质量参数分析的质量控制主要是质量控制材料的选择,以及在男科学实验室实施EQC和IQC项目,而一些监测质量控制的图表和计算方法应被相应地建立。  相似文献   
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