Chromatin Packaging as an Indicator of Human Sperm Dysfunction

Purpose: Understanding the causes of fertilization failure is an important research field in assisted reproductive programs. The present study aimed to evaluated the possible relationship between chromatin packaging quality (CMA₃ staining) and (i) normal morphology and (ii) its ability to predict the functional integrity of spermatozoa in both in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) treatment programs. Methods: Semen of 140 men from IVF and ICSI couples were analyzed for sperm concentration, motility, morphology, and chromatin packaging (CMA₃). For CMA₃ classification, two cutoff values were used, namely, 44.5%±13 and 1 SD above the mean, i.e., 57.5% (rounded off to 60%). IVF and ICSI data were stratified using three basic cutoff values for CMA₃ staining, namely, <44%, >44–60%, and >60%. Results: Based on CMA₃ results patients were divided into four groups, namely, group A, <44% CMA₃ (n = 15, IVF); group B, 44% and <60% CMA₃ (n = 39, IVF); group C, 60% CMA₃ (n = 45 IVF); and group D, 60% CMA₃(n = 41 ICSI). During receiver operator characteristic analyses the estimated cutoff value for CMA₃ staining, to distinguish between <4% and 4% morphology groups, was 60%. The area under the curve was 0.89, sensitivity of 75%, and specificity of 100%. When IVF rates of >60% and <60% were used, the optimal CMA₃ value for prediction of fertilization success again was recorded at 60%. The area under the curve was 0.76, sensitivity of 81.5%, and specificity of 63.6%. Conclusions: Chromatin packaging assessments should be included as a complementary assay to the sequential diagnostic approach of the male-factor patients.     

Physiological Induction of the Acrosome Reaction in Human Sperm: Validation of a Microassay Using Minimal Volumes of Solubilized, Homologous Zona Pellucida

Purpose: To develop a method that could accommodatemicrovolumes of solubilized human zona pellucida (ZP) andsperm for assessing the induction of the acrosome reaction. Methods: A microassay using 1 l of 2.5, 1.25, 0.6, 0.3,and 0.125 ZP/l incubated with 1 l of a highly motilesperm suspension for 60 min. As a control and parallelto the microassay a standard acrosome reaction techniquewas performed. Results: No significant differences were observed betweenthe percentage acrosome reacted sperm reported by the twoassays under basal conditions (spontaneous) or after inductionwith a Ca²⁺ ionophore or solubilized ZP. At a ZPconcentration of 0.6 ZP/l, the percentages of acrosome-reactedspermatozoa in both techniques were significantlyhigher compared to the spontaneous acrosome reactionresults, namely, 18% and 17%, compared to 10% and 10%,respectively. An approximately 30% level of acrosomal exocytosiswas induced with 2.5 ZP/l in both methods. Conclusions: This newly devised microtechnique is easy andrapid to perform, is repeatable and facilitates the use ofminimal volumes of solubilized human ZP (even a single ZP)for assessment of the inducibility of the acrosome reaction ofa homologous sperm population.     

A new amino acid mixture permits new approaches to the treatment of phenylketonuria

A new amino acid mixture for incorporation into medical foods for the treatment of hyperphenylalaninemia has been tested in a regular clinic. The mix is designed to be as unobtrusive as possible, consistent with good nutrition. After more than 1 year of trial as a beverage, we have shown that it is safe and well tolerated but that plasma phenylalanine is no better controlled than with some other products. The mix can be incorporated into a large number of different foods without affecting the taste. Occult monitoring of the quantity of medical foods purchased compared with the amounts reported to be consumed in diet histories provides an excellent way to monitor dietary compliance.     

Selective cognitive processing of drug cues in heroin dependence

Previous studies provide evidence for the selective processing of disorder related stimuli on anxiety, depression, and eating disorders. There exist some preliminary indications that selective processing of drug cues may be involved in drug craving and relapse that deserve further investigation. In order to investigate the role of processing bias in an abnormal motivational system, the attentional bias for drug related stimuli was studied in a heroin dependent population. Heroin dependent participants (n = 21) and control participants (n = 30) performed a supra- and subliminal heroin Stroop task and heroin craving was assessed. Heroin dependent participants showed a considerable attentional bias for supraliminally presented heroin cues. However, there was no evidence for a preattentive bias on the subliminal presented cues. Reaction time on heroin cues was significantly predicted by heroin craving-levels. Results indicate that selective processing may be related to motivational induced states in general. The finding are discussed in the context of selective information processing in general psychopathology and in motivational processes as addiction specifically.     

Early-onset of illicit substance use is associated with greater axis-II comorbidity, not with axis-I comorbidity

In the present study the relationship between early-onset (相似文献   

Influence of individual differences in craving and obsessive cocaine thoughts on attentional processes in cocaine abuse patients

In the present pilot-study, the relation between craving, obsessive thoughts about cocaine, experienced control, and attentional bias for cocaine related words is investigated. Sixteen cocaine abuse patients participated in a reaction time (RT) experiment which was employed to measure the ability of subjects to shift their attention away from cocaine related words. Postexperiment craving was found to be positively correlated with reaction times on drug related cues, in contrast to RT on neutral cues. Furthermore, obsessive thoughts about cocaine use and the experienced cocaine use control, in the week before the experiment, were correlated in a higher degree with RTs on drug cues than postexperiment craving. Attentional bias for drug cues was evidenced in patients with higher scores on obsessive cocaine thoughts and higher craving scores. This study shows that individual differences on information processing, within a cocaine abuse patient population, are present.     

BrdUrd-induced radiosensitization of two human tumour cell lines at iso-levels of incorporation

Bromodeoxyuridine (BrdUrd)-induced radiosensitization of two different tumour cell lines was compared at equal levels of thymidine replacement. Human lung carcinoma cells (SW-1573) and human colorectal carcinoma cells (RKO) were grown for 48 h in the presence of respectively 1 microM BrdUrd and 4 microM of BrdUrd in order to obtain equal levels of BrdUrd into the DNA. In SW cells the level of thymidine replacement by BrdUrd was 6.7+/-0.5% and in RKO cells this was 7.1+/-0.8. Cell survival after irradiation with single doses up to 8 Gy, was determined with clonogenic assay. The magnitude of BrdUrd-induced radiosensitization was determined by analyzing radiation-dose survival curves with the linear-quadratic formula [S(D)/S(0)=exp-(alphaD+betaD2)]. In the SW cells BrdUrd radiosensitization led to a significant increase of the linear parameter, alpha, determining the initial slope of the survival curves, by a factor of about 2. In the RKO cells BrdUrd increased the value of alpha by a factor 1.4. This suggests that repair of potentially lethal damage (PLD) is inhibited. In both cell lines the quadratic term, beta, strongly influencing the high dose region of the survival curves, was not altered by sensitization by BrdUrd. The increase of alpha is of interest for clinical applications as BrdUrd sensitizes tumour cells after low doses of radiation.     

The effect of pentoxifylline on sperm movement characteristics and zona pellucida binding potential of teratozoospermic men

This study investigates the effect of pentoxifylline on spermmovement and zona pellucida binding. Spermatozoa from nine teratozoospermicpatients (10.2 ± 6% normal forms) were included in thestudy. Test samples were diluted with a 4 mM solution of pentoxifylline,and control samples with Ham's F-10 culture medium only. Zonapellucida binding potential was measured under hemizona assayconditions (HZA). Sperm motility was evaluated at the start(0 h postswim-up) and end (4 h) of the HZA, under test-tubeconditions and under HZA conditions (50µ droplet underoil). Motilityparameters tested included the curvilinear velocity(VCL), straight line velocity (VSL) and linearity (LIN). Comparedto the controls, pentoxifylline-treated samples showed an immediatestimulation of sperm motility, under test-tube conditions, witha significant elevation of VCL at 0 h incubation (102.77 ±14.4 versus control value 84.60 ± 10.6 µm/s; P< 0.005), which however was reversed after 4 h incubation(73.16 ± 4.6 versus control value 85.47 ± 12.8µm/s; P < 0.005). A decline in sperm motility from0 to 4 h incubation was noted for all the pentoxifylline-treatedsamples, under both test tube conditions (VCL: 102.77 ±14.4 versus 73.16 ± 4.6 µm/s, P <<;<<0.005; VSL: 27.2 ± 10 versus 10.66 ± 2.2 µm/P <<; 0.005; LIN: 23.65 ± 7.1 versus 11.86 ±1.8%, P<<; 0.005) and HZA conditions (VCL: 100.04 ±13.1 versus 76.00 ± 7 µm/s, P <<; 0.005;VSL: 26.40 ± 8.7 versus 9.14 ± 4.5 µm/s,P <<; 0.005; LIN: 26.2 ± 12 versus 11.05 ±4.3%, P <<; 0.005). Pentoxifylline also showed no effecton the zona binding capacity of the sperm population, sinceno significant difference in zona binding capacity was seenbetween control and test samples. In conclusion, the effectof pentoxifylline on teratozoospermic spermatozoa is short-lived,and despite its stimulatory potential pentoxifylline shows nobeneficial use in enhancing zona pellucida binding of teratozoospermicspermatozoa.