Unprotected freezing of human spermatozoa exerts a detrimental effect on their oocyte activating capacity and chromosome integrity

Zygote ◽  
1996 ◽  
Vol 4 (04) ◽  
pp. 263-268 ◽  
Author(s):  
Andrei V. Rybouchkin ◽  
Paul De Sutter ◽  
Marc Dhont
Keyword(s):  
Assisted Reproduction ◽  
Detrimental Effect ◽  
Chromosomal Abnormalities ◽  
Ethanol Solution ◽  
Human Spermatozoa ◽  
Physical Factors ◽  
Reproductive Characteristics ◽  
Chromosome Integrity ◽  
The Stability ◽  
Mammalian Spermatozoa

SummaryThe influence of unprotected freezing of mammalian spermatozoa on their oocyte activating capacity and chromosome integrity is unknown. However, this type of sperm treatment has been used in assisted reproduction by intracytoplasmic sperm injection in cattle and humans. The mouse oocyte injection test was used to analyse the influence of unprotected freezing of human spermatozoa on their reproductive characteristics. Mouse oocytes were microinjected with intact human spermatozoa or spermatozoa treated with two cycles of unprotected freeze-thawing. Oocytes surviving the injection were either cultured without further treatment or exposed to ethanol solution to induce parthenogenetic activation. Both injected and activated oocytes were used for sperm chromosome analysis. The results revealed a significant reduction in oocyte activating capacity and a tenfold increase in the incidence of structural chromosomal abnormalities in human spermatozoa treated by unprotected freezing. We conclude that unprotected freezing of human spermatozoa has a detrimental effect on their reproductive characteristics. Our data also provide a new perspective on the stability of mammalian spermatozoa to physical factors and demonstrate the importance of detailed analysis of the stability of sperm structures for successful development of new approaches in assisted reproduction.

The Fine Structure of Glycocalyx in Human Spermatozoa. A High Resolution Cytochemical Study

1973 ◽  
Vol 31 ◽  
pp. 640-641
Author(s):  
P. Hernández-Jáuregui ◽  
A. Sosa ◽  
A. González Angulo
Keyword(s):  
Negative Charge ◽  
Iron Hydroxide ◽  
Human Spermatozoa ◽  
Surface Coat ◽  
Cell Surfaces ◽  
Colloidal Iron ◽  
Cytochemical Study ◽  
Specific Permeability ◽  
Extracellular Glycoprotein ◽  
Mammalian Spermatozoa

Glycocalyx is the name given by Bennett to the extracellular glycoprotein coat present in some cell surfaces. It appears to play an important role in cell properties such as antigenicity, cell adhesivity, specific permeability, and ATP ase activity. In the sperm this coat can be directly related to such important phenomena as capacitation and fertilization. The presence of glycocalyx in invertebrate spermatozoa has already been demonstrated. Recently Yanagimachi et al. has determined the negative charges on sperm surfaces of mammalian spermatozoa including man, using colloidal iron hydroxide. No mention was made however of the outer surface coat as composed of substances other than those confering a negative charge. The purpose of this work was therefore to determine the presence of a glycocalyx in human spermatozoa using alcian blue and lanthanum staining.

CRITICAL REVIEW OF EMULSION STABILITY AND CHARACTERIZATION TECHNIQUES IN OIL PROCESSING

2021 ◽  
pp. 1-36
Author(s):  
Vahideh Angardi ◽  
Ali Ettehadi ◽  
Özgün Yücel
Keyword(s):  
Separation Efficiency ◽  
Petroleum Industry ◽  
Cost Effective ◽  
Downstream Processing ◽  
Physical Factors ◽  
Comprehensive Review ◽  
Factors Affecting ◽  
Mathematical Explanations ◽  
The Stability ◽  
The Right

Abstract Effective separation of water and oil dispersions is considered a critical step in the determination of technical and economic success in the petroleum industry over the years. Moreover, a deeper understanding of the emulsification process and different affected parameters is essential for cost-effective oil production, transportation, and downstream processing. Numerous studies conducted on the concept of dispersion characterization indicate the importance of this concept, which deserves attention by the scientific community. Therefore, a comprehensive review study with critical analysis on significant concepts will help readers follow them easily. This study is a comprehensive review of the concept of dispersion characterization and conducted studies recently published. The main purposes of this review are to 1) Highlight flaws, 2) Outline gaps and weaknesses, 3) Address conflicts, 4) Prevent duplication of effort, 5) List factors affecting dispersion. It was found that the separation efficiency and stability of dispersions are affected by different chemical and physical factors. Factors affecting the stability of the emulsions have been studied in detail and will help to look for the right action to ensure stable emulsions. In addition, methods of ensuring stability, especially coalescence are highlighted, and coalescence mathematical explanations of phenomena are presented.

scholarly journals Too Stressed to Teach? Teaching Quality, Student Engagement, and IEP Outcomes

2017 ◽  
Vol 83 (4) ◽  
pp. 412-427 ◽  
Author(s):  
Venus W. Wong ◽  
Lisa A. Ruble ◽  
Yue Yu ◽  
John H. McGrew
Keyword(s):  
Student Engagement ◽  
Indirect Effects ◽  
Detrimental Effect ◽  
Teacher Stress ◽  
Individualized Education Program ◽  
Student Learning Outcomes ◽  
Teaching Quality ◽  
Autism Spectrum ◽  
Personal Accomplishment ◽  
The Stability

Teacher stress and burnout have a detrimental effect on the stability of the teaching workforce. However, the possible consequences of teacher burnout on teaching quality and on student learning outcomes are less clear, especially in special education settings. We applied Maslach and Leiter’s (1999) model to understand the direct effects of burnout on teaching in general and stress arising from interaction with a specific student on the individualized education program (IEP) outcomes of young children with autism spectrum disorder. We also examined indirect effects through teaching quality and student engagement. The results indicated that one of the three components of burnout—teacher personal accomplishment—was directly related to IEP outcomes, a distal effect, whereas stress was directly related to teaching quality and student engagement, which were more proximal effects. In addition, teacher stress, emotional exhaustion, and depersonalization had indirect effects on IEP outcomes through teaching quality and student engagement.

scholarly journals Color Stability of Phycoerythrin Crude Extract (PECE) from Rhodomonas Salina Toward Physicochemical Factors

2019 ◽  
Vol 14 (1) ◽  
pp. 21
Author(s):  
Endar Marraskuranto ◽  
Tri Joko Raharjo ◽  
Rina Sri Kasiamdari ◽  
Tri Rini Nuringtyas
Keyword(s):  
Phosphate Buffer Solution ◽  
Color Stability ◽  
Ethanol Solution ◽  
Future Application ◽  
Buffer Solution ◽  
Solution Ph ◽  
Rhodomonas Salina ◽  
Freeze Dried ◽  
Physicochemical Factors ◽  
The Stability

Rhodomonas salina produces Cr-phycoerythrin545 as its designated phycoerythrin (PE) with an absorption maximum at 545 nm and a shoulder 564 nm. PE has potential to be applied as colorants, pharmaceutical agents, and fluorescent dye tags. The stability of the PE color is influenced by the physicochemical factors of the solution. This study aimed to analyze the color stability of PECE against chemical (ethanol and pH) and physical (light and temperature) factors. PECE was prepared from freeze-dried biomass of R. salina and was extracted in phosphate buffer solution (pH = 6.0) using a freeze-thaw method in -25 oC (2 hours) and 4 oC (24 hours). The resulting extract was concentrated and dried in a freeze-dryer. Analyses were conducted using UV-visible and fluorescence spectrophotometer. PECE showed color stability against light of white fluorescent lamp exposure up to 8 hours, temperature exposure up to 40 oC, ethanol solution up to concentration of 20 % (v/v), and pH range 3.9-8.42. Results from this study can be useful for extraction, purification, and future application of Cr-PE545.

scholarly journals DNA damage of human spermatozoa in assisted reproduction: origins, diagnosis, impacts and safety

2007 ◽  
Vol 14 (3) ◽  
pp. 384-395 ◽  
Author(s):  
B Ozmen ◽  
N Koutlaki ◽  
M Youssry ◽  
K Diedrich ◽  
S Al-Hasani
Keyword(s):  
Dna Damage ◽  
Assisted Reproduction ◽  
Human Spermatozoa

Separation of motile human spermatozoa in assisted reproduction: evaluation of centrifugation and non-centrifugation-based techniques

2000 ◽  
Vol 73 (4) ◽  
pp. S13-S14
Author(s):  
M Perloe ◽  
K.M Wittkowski ◽  
E.S Sills ◽  
M.J Tucker ◽  
G.D Palermo
Keyword(s):  
Assisted Reproduction ◽  
Human Spermatozoa

scholarly journals Species difference in the expression of Fas and Fas ligand in mature mammalian spermatozoa

2017 ◽  
Vol 62 (No. 12) ◽  
pp. 519-526
Author(s):  
Y. Li ◽  
M. Sun ◽  
J. Zhu ◽  
G. Jiao ◽  
J. Lin ◽  
...  
Keyword(s):  
Fas Ligand ◽  
Species Difference ◽  
Female Genital Tract ◽  
Human Spermatozoa ◽  
Whole Body ◽  
Fasl Expression ◽  
Weak Signals ◽  
Boar Spermatozoa ◽  
Mature Spermatozoa ◽  
Mammalian Spermatozoa

Although it has been proposed that the Fas and Fas ligand (FasL) may protect ejaculated spermatozoa against apoptosis induced by lipoperoxidative damage and against lymphocytes present in the female genital tract, studies reported conflicting results on the presence of Fas receptors in ejaculated human spermatozoa. Furthermore, the expression of Fas/FasL on mature spermatozoa has not been observed in several important mammals. Using seven species, we observed the possibility for species difference in Fas/FasL expression on mature spermatozoa by both immunofluorescence microscopy and western blot analysis. Whereas intensive signals of Fas immunolabelling were detected in sperm head and middle piece and weak signals observed in the tail in 86–100% of the mouse, rat, bull, ram, and buck spermatozoa, only weak signals were detected on the whole body of 27% boar spermatozoa and in the head of 21% human spermatozoa. The pattern of FasL localization was identical to that of Fas in spermatozoa from human, mouse, rat, ram, and buck, but boar and bull spermatozoa showed weak and intensive FasL signals, respectively, only in the head. Western blotting further confirmed the Fas and FasL expression in mouse, rat, bull, ram, and buck, but not in human and boar spermatozoa. Taken together, the results revealed a marked species difference in Fas/FasL expression and an extensive co-expression of Fas and FasL among mature mammalian spermatozoa, suggesting that whereas spermatozoa from most species may be protected by Fas/FasL, those from human and boar may not use the Fas system for protection.

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