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Sperm DNA integrity could be considered a biological marker of sperm quality and may affect fertilization, embryonic development, and pregnancy outcome. The study aimed to investigate the connection between semen characteristics and sperm DNA damage in infertile patients. Standard semen analysis of 536 samples was carried out following the World Health Organization (WHO) 5th edition recommendations. Sperm DNA damage was assessed by the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay, after preparation by direct swim-up. The slides were evaluated using a fluorescence microscope and the percentage of TUNEL-positive spermatozoa was expressed as the DNA fragmentation index (DFI). Patients were classified according to their DFI levels: group A (DFI < 15%) and group B (DFI ≥15%). Sperm total count, concentration, total and progressive motility, vitality, and normal morphology were significantly higher in group A compared to group B (p < 0.001). The results show a significant inverse correlation between DFI and patient's age, sperm total count, concentration, total and progressive motility, vitality and normal morphology. Higher DFI values were found to be strongly associated with poor sperm quality. In conclusion, combined with conventional semen analysis, assessment of sperm DFI could improve diagnostic accuracy and treatment management for patients with male infertility., (© 2022 Wiley-VCH GmbH.)

The aim of this study was to evaluate whether there is a difference between gravimetrically and volumetrically measured semen samples and to assess the impact of semen volume, density, and sperm count on the discrepancy between gravimetric and volumetric methods. This study was designed in an andrology laboratory setting and performed on semen samples of 1,055 men receiving infertility treatment. Semen volume was calculated by gravimetric and volumetric methods. The total sperm count, semen density and sperm viability were also examined according to recent version of World Health Organization manual. The median values for gravimetric and volumetric measurements were 3.44 g and 2.96 ml respectively. The numeric difference in semen volume between 2 methods was 0.48. The mean density of samples was 1.01 ± 0.46 g/ml (range 0.90-2.0 g/ml). The numeric difference between 2 methods gets higher as semen volume increases (p < 0.001). Gravimetric and volumetric semen volume measurements were strongly correlated for all samples and for each subgroup of semen volume, semen density and sperm count, with minimum correlation coefficient of 0.895 (p < 0.001). In conclusion, the gravimetric measurement provides higher results than volumetric one and numeric differences between 2 methods increase as semen volume increases. However, further studies are needed to offer the use of gravimetrical method, which was thought to minimize laboratory errors, particularly for a high amount of semen samples., (© 2016 S. Karger AG, Basel.)

We aimed to investigate the role of thioredoxin reductase (TR) and inducible heat shock protein 70 (iHsp70) and their relationship with sperm quality in varicocele (VAR) patients. Semen samples were obtained from 16 subfertile men diagnosed as VAR and 10 fertile men who applied to the Andrology Laboratory of Istanbul Medical Faculty of Istanbul University. The sperm TR and iHsp 70 expression levels were determined using Western blot analysis. The TR activity of the sperm was assayed spectrophometrically. The sperm quality was evaluated both by conventional sperm analysis and by a terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) technique that assayed DNA-fragmented spermatozoa in semen samples. The percentage of TUNEL-positive spermatozoa in the VAR group (16.3%± 5.6%) was higher than that in the fertile group (5.5%± 1.9%). Significant inverse correlations were detected between the percentage of TUNEL-positive cells and both the concentration (r=-0.609; P=0.001) and motility (r=-0.550; P=0.004) of spermatozoa. Both the TR expression and activity were increased significantly in the VAR group (U=22.0; P=0.001 and U=33.5; P=0.012, respectively) as analyzed using the Mann-Whitney U Wilcoxon rank sum W test. Furthermore, significant positive correlations were found between TR expression and activity (r=0.406; P=0.040) and between TR expression and the percentage of TUNEL-positive cells (r=0.665; P=0.001). Sperm iHsp70 expression did not differ between the VAR and fertile groups. In conclusion, increased sperm TR expression might be a defense mechanism against apoptosis in the spermatozoa of men with VAR.

Objective: To study the role of oxidative stress in sperm dysfunction in Turkish idiopathic infertile men., Design: Prospective study., Setting: Medical laboratory., Patient(s): Semen samples from 28 idiopathic infertile men and 14 fertile men., Intervention(s): Sperm DNA fragmentation and reactive oxygen species (ROS) formation were assayed with the terminal deoxynucleotide transferase-mediated dUTP nick-end labeling (TUNEL) test and 2',7'-dichlorodihydrofluorescein, respectively. Seminal plasma protein carbonyl groups (PC), nitrotyrosine (NT), malondialdehyde (MDA), and total thiol (SH) levels and ferric reducing antioxidant power (FRAP) were determined., Main Outcome Measure(s): Sperm DNA fragmentation in relation to ROS formation and seminal plasma oxidative parameters., Result(s): The number of TUNEL-positive spermatozoa from idiopathic infertile men was higher than from fertile men, and ROS formation was increased as well in infertile males. A positive correlation was detected between TUNEL-positive cells and ROS content. Seminal plasma MDA, PC, and NT levels were elevated in idiopathic infertile males. No difference was observed in the total SH content and FRAP. Seminal plasma MDA levels correlated positively with both NT and PC levels. Positive correlations were detected between DNA fragmentation and MDA, NT, and PC of seminal plasma, and between sperm ROS content and MDA levels., Conclusion(s): The results of this study support the presence of oxidative stress in sperm dysfunction in Turkish idiopathic infertile men., (Copyright © 2013 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.)

Objective: To clarify the role of heat shock protein 70 (Hsp 70) and its relation with DNA damage in male infertility., Design: Prospective study., Setting: Andrology laboratory of Istanbul Medical Faculty., Patient(s): Semen samples from 37 infertile men and 13 fertile men (as controls)., Intervention(s): The percentage of DNA fragmentation was assayed with the use of terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL). Sperm Hsp 70 expression was determined by using Western blot analysis., Main Outcome Measure(s): Both the percentages of sperm DNA fragmentation and Hsp 70 expression were correlated with semen analysis parameters., Results: TUNEL-positive spermatozoa in the infertile group (18.7% for asthenospermics and 13.0% for oligoasthenospermics) were higher than the fertile group (4.9%). Significant inverse correlations were detected between percentage of TUNEL-positive cells and both concentration (r = -0.487) and motility (r = -0.377) of spermatozoa. No expression of Hsp 70 was observed in azospermic group, whereas Hsp 70 levels were found increased significantly in infertile group (U = 62 for asthenospermics and U = 38 for oligoasthenospermics) compared to fertile group as analyzed by using Mann-Whitney U Wilcoxon rank sum test. Furthermore, significant positive correlation was found between percentage of TUNEL-positive cells and Hsp 70 expression (r = 0.357)., Conclusion(s): Hsp 70 expression may have been increased as a protective mechanism against apoptosis in spermatozoa of infertile men.