The Relationship Between Sperm Velocity and Pressures Applied to the Zona Pellucida During Early Sperm-Oocyte Penetration

2010 ◽  
Vol 132 (12) ◽  
Author(s):  
Amit Gefen
Keyword(s):  
Zona Pellucida ◽  
Early Phase ◽  
Sperm Quality ◽  
Sperm Head ◽  
Velocity Measurements ◽  
Sperm Velocity ◽  
Important Indicator ◽  
Sperm Penetration ◽  
The Relationship ◽  
Relevant Range

Sperm velocity is long known to be an important indicator of sperm quality but without much biophysical theory explaining it. Contact mechanics based modeling was developed here to determine the effects that sperm velocity (vs) and sperm head density (ρs)—which is an indicator of the stiffness of the head, have on the peak sperm-zona pellucida contact pressure (pm) during the early phase of sperm penetration. The modeling identified vs as being more influential on pm compared with the influence that ρs has, which means that for spermatozoa competing on the same oocyte, greater vs is a more important advantage than higher ρs. Specifically, pm was more sensitive by a power of 2 to changes in vs than to changes in ρs. It was further demonstrated that each 0.1 g/cc increase in ρs (within the physiologically relevant range of 1.3–1.7 g/cc) would be equivalent to just ∼3% rise in vs, indicating again that faster swimming is a better strategy for spermatozoa compared with head stiffening. The modeling hence provided some useful insights regarding sperm biomechanics, which theoretically elucidate the well-recognized importance of sperm velocity measurements as being indicative of sperm quality.

scholarly journals Dynamics of flagellar force generated by a hyperactivated spermatozoon

Reproduction ◽  
2011 ◽  
Vol 142 (3) ◽  
pp. 409-415 ◽  
Author(s):  
Sumio Ishijima
Keyword(s):  
Zona Pellucida ◽  
High Speed ◽  
Beat Frequency ◽  
Transverse Force ◽  
Sperm Head ◽  
Propulsive Force ◽  
Resistive Force ◽  
High Speed Video ◽  
Sperm Penetration ◽  
Resistive Force Theory

The flagellar force generated by a hyperactivated monkey spermatozoon was evaluated using the resistive force theory applied to the activated (nonhyperactivated) and hyperactivated flagellar waves that were obtained using high-speed video microscopy and digital image processing in order to clarify the mechanism of sperm penetration through the zona pellucida. No difference in the maximum propulsive force, which was parallel to the longitudinal sperm head axis, was found between the activated and hyperactivated spermatozoa. The maximum transverse force (45 pN), which was perpendicular to the longitudinal sperm head axis, of the hyperactivated spermatozoon was ∼2.5 times its propulsive force. As the beat frequency of the flagellar beating remarkably decreased during the hyperactivation, the slowly oscillating transverse force (5 Hz) by the hyperactivated spermatozoon seems to be most effective for sperm penetration through the zona pellucida.

Sperm Penetration of the Zona Pellucida of the Pig Egg

1964 ◽  
Vol 41 (3) ◽  
pp. 603-608
Author(s):  
Z. DICKMANN ◽  
P. J. DZIUK
Keyword(s):  
Zona Pellucida ◽  
Phase Contrast ◽  
Sperm Head ◽  
Narrow Slit ◽  
Penetration Curve ◽  
Phase Contrast Microscope ◽  
Sequence Of Events ◽  
Contrast Microscope ◽  
Sperm Penetration

1. Pig eggs were examined with the ordinary and phase-contrast microscope in search for clues about the process of sperm penetration of the zona pellucida. 2. The following observations were made, (i) The zona pellucida consists of three concentric layers--the inner-zona, the middle-zona, and the outer-zona. (ii) The fertilizing spermatozoon makes a narrow slit in the zona by penetrating through it. The slit has a particular shape referred to as ‘the penetration curve’. (iii) Extra spermatozoa (i.e. spermatozoa other than the fertilizing spermatozoon) enter the zona and follow a course very similar to that of the fertilizing spermatozoon, but they can penetrate it only as far as the middle-zona. Extra spermatozoa have not been observed in the inner-zona, indicating that in this layer the ‘zona reaction’ is normally absolute, (iv) A filament extending from the apex of the sperm head has been observed in spermatozoa embedded in the zona. It is suggested that the sperm path through the zona is determined by this filament, which is therefore termed the sperm-penetration filament (SPF). 3. On the basis of these observations the following sequence of events in the passage of a spermatozoon through the zona is suggested. First, the spermatozoon attaches to the zona; it then ejects into the zona the SPF. The SPF, in turn, guides the spermatozoon on its curved course through the zona.

50 ESTIMATION OF CHROMATIN ABNORMALITY OF OGYE ROOSTER SEMEN WITH Diff-Quik STAINING

2016 ◽  
Vol 28 (2) ◽  
pp. 155
Author(s):  
S. W. Kim ◽  
A. R. Choi ◽  
C. Y. Choe ◽  
D. K. Kim ◽  
H. H. Seong ◽  
...  
Keyword(s):  
Staining Method ◽  
Sperm Quality ◽  
Sperm Head ◽  
Head Movements ◽  
Sperm Chromatin ◽  
Frozen Semen ◽  
Sperm Nuclei ◽  
Live Sperm ◽  
The Relationship ◽  
Fresh Semen

The abnormality of Ogye rooster sperm chromatin could be detected by simple sperm staining. In this abstract, a Diff-Quick staining kit was tested for assessment of chicken sperm quality. Using a standard bright-field microscope, Diff-Quik stains can be reproducibly, easily, and routinely monitored with simple staining. The presence of abnormal chromatin staining of rooster sperm was determined by darker stain in head. In the fresh semen, the viabilities of 3 tested Ogye spermatozoa were 93.53, 82.42, and 90.63%, and normal chromatin rates were 87.96, 74.25, and 85.10%, respectively. However, after cryopreservation, the rates of viability of thawed semen were reduced to 69.58, 61.98, and 72.20%, and normal chromatin rate also reduced to 58.91, 48.49, and 63.34%. A significant correlation between live sperm and normal sperm nuclei was 0.875 in fresh semen and 0.513 in frozen semen. After incubation of sperm at 37°C for 5 min, the rates of viability, chromatin normality, and sperm head activity were shown as 90.63 ± 1.28%, 82.44 ± 8.09%, and 66.68 ± 10.29% in fresh semen. However, the rates of thawed semen were reduced to 67.92 ± 7.55%, 56.92 ± 12.15%, and 47.32 ± 5.02%, respectively. The relationship between chromatin normality and sperm head movements in fresh and thawed semen were 0.564 and 0.540, respectively. With these results, the chicken sperm normality could be assessed by the Diff-Quik staining, which could be used for chromatin status of sperm head and activated morphology of live spermatozoa, as a simple and rapid staining method.

Reproductive characteristics of the african pygmy hedgehog, atelerix albiventris

Reproduction ◽  
2000 ◽  
pp. 143-150 ◽  
Author(s):  
JM Bedford ◽  
OB Mock ◽  
SK Nagdas ◽  
VP Winfrey ◽  
GE Olson
Keyword(s):  
Fallopian Tube ◽  
Zona Pellucida ◽  
Sperm Head ◽  
Reproductive Characteristics ◽  
Cumulus Oophorus ◽  
The Matrix ◽  
Main Components ◽  
Initial Binding ◽  
Structural Matrix

To obtain further perspective on reproduction and particularly gamete function among so-called primitive mammals presently grouped in the Order Insectivora, we have examined the African hedgehog, Atelerix albiventris, in light of unusual features reported in shrews and moles. Atelerix proves to share many but not all of the characteristics seen in these other insectivores. The penis of Atelerix has a 'snail-like' form, but lacks the surface spines common in insectivores and a number of other mammals. Hedgehog spermatozoa display an eccentric insertion of the tail on the sperm head, and they manifest the barbs on the perforatorium that, in shrews, probably effect the initial binding of the sperm head to the zona pellucida. As a possible correlate, the structural matrix of the hedgehog acrosome comprises only two main components, as judged by immunoblotting, rather than the complex of peptides seen in the matrix of some higher mammals. The Fallopian tube of Atelerix is relatively simple; it displays only minor differences in width and in the arborized epithelium between the isthmus and ampulla, and shows no evidence of the unusual sperm crypts that characterize the isthmus or ampulla, depending on the species, in shrews and moles. In common with other insectivores, Atelerix appears to be an induced ovulator, as judged by the ovulation of some 6-8 eggs by about 23 h after injection of hCG. The dense cumulus oophorus appeared to have little matrix, in keeping with the modest dimensions of the tubal ampulla and, while it was not quite as discrete as that of soricids, it did show the same insensitivity to 0.5% (w/v) ovine or bovine hyaluronidase.

scholarly journals CagA-PositiveHelicobacter pyloriInfection and Reduced Sperm Motility, Vitality, and Normal Morphology

2013 ◽  
Vol 35 ◽  
pp. 229-234 ◽  
Author(s):  
E. Moretti ◽  
G. Collodel ◽  
L. Mazzi ◽  
M. S. Campagna ◽  
N. Figura
Keyword(s):  
Sperm Motility ◽  
Normal Forms ◽  
Molecular Mimicry ◽  
Sperm Quality ◽  
Semen Analysis ◽  
Normal Morphology ◽  
Partial Linear ◽  
Caga Status ◽  
The Relationship ◽  
Autoimmune Phenomena

Helicobacter pylori(HP) infection, particularly when caused by strains expressing CagA, may be considered a concomitant cause of male and female reduced fertility. This study explored, in 87 HP-infected males, the relationship between infection by CagA-positive HP strains and sperm parameters. HP infection and CagA status were determined by ELISA and Western blotting; semen analysis was performed following WHO guidelines. The amino acid sequence of human enzymes involved in glycolysis and oxidative metabolism were “blasted” with peptides expressed by HP J99. Thirty-seven patients (42.5%) were seropositive for CagA. Sperm motility (18% versus 32%; ), sperm vitality (35% versus 48%; ) and the percentage of sperm with normal forms (18% versus 22%; ) in the CagA-positive group were significantly reduced versus those in the CagA-negative group. All the considered enzymes showed partial linear homology with HP peptides, but four enzymes aligned with four different segments of the samecagisland protein. We hypothesize a relationship between infection by strains expressing CagA and decreased sperm quality. Potentially increased systemic levels of inflammatory cytokines that occur in infection by CagA-positive strains and autoimmune phenomena that involve molecular mimicry could explain the pathogenetic mechanism of alterations observed.

scholarly journals Relationship between Changes over Time in Factors, Including the Impact of Meteorology on Photochemical Oxidant Concentration and Causative Atmospheric Pollutants in Kawasaki

Atmosphere ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 446
Author(s):  
Akinori Fukunaga ◽  
Takaharu Sato ◽  
Kazuki Fujita ◽  
Daisuke Yamada ◽  
Shinya Ishida ◽  
...  
Keyword(s):  
Moving Average ◽  
Atmospheric Pollutants ◽  
Important Indicator ◽  
Photochemical Oxidant ◽  
Oxidant Concentration ◽  
Using Data ◽  
Changes Over Time ◽  
The Impact ◽  
The Relationship ◽  
The City

To clarify the relationship between changes in photochemical oxidants’ (Ox) concentrations and their precursors in Kawasaki, a series of analyses were conducted using data on Ox, their precursors, nitrogen oxides (NOx) and volatile organic compounds (VOCs), and meteorology that had been monitored throughout the city of Kawasaki for 30 years from 1990 to 2019. The trend in air temperature was upward, wind speed was downward, and solar radiation was upward, indicating an increasing trend in meteorological factors in which Ox concentrations tend to be higher. Between 1990 and 2013, the annual average Ox increased throughout Kawasaki and remained flat after that. The three-year moving average of the daily peak increased until 2015, and after that, it exhibited a slight decline. The amount of generated Ox is another important indicator. To evaluate this, a new indicator, the daytime production of photochemical oxidant (DPOx), was proposed. DPOx is defined by daytime averaged Ox concentrations less the previous day’s nighttime averaged Ox concentrations. The trend in DPOx from April to October has been decreasing since around 2006, and it was found that this indicator reflects the impact of reducing emissions of NOx and VOCs in Kawasaki.

scholarly journals Comparative analysis of sports consumption habits in Hungary, Poland and Germany

2021 ◽  
Vol 21 (S1) ◽  
Author(s):  
Dávid Paár ◽  
Antal Kovács ◽  
Miklós Stocker ◽  
Márk Hoffbauer ◽  
Attila Fazekas ◽  
...  
Keyword(s):  
Physical Activity ◽  
Material Wealth ◽  
Important Indicator ◽  
Sports Clubs ◽  
Research Findings ◽  
Study Population ◽  
Sports Consumption ◽  
The Difference ◽  
Sports Venues ◽  
The Relationship

Abstract Background The so-called sports consumption models are looking for the factors that influence the sports spending of households. This paper aims to examine the Hungarian, Polish and German households’ sports expenditures which can be an important indicator of physical activity and sporty lifestyle. Methods Surveying of households in three countries (Hungary, Poland and Germany) has been conducted with a self-designed questionnaire. We have used descriptive and bivariate non-parametric and parametric statistical methods: (1) χ2 test, Mann-Whitney test and Kruskal-Wallis test for checking the relationship between sociodemographic and physical activity variables and (2) independent sample t-test and ANOVA for checking the differences in sports expenditures. Results Our research concluded that men, especially previous athletes, exercise more than women and those who have no history as registered athletes. The choice of sports venues is obviously different between the countries in the sample. Members of the study population spend the most on sports services while they spend the least on sports equipment. German households have the highest spending rates compared to the other two countries. Conclusions Results are in line with our previous research findings and with other literatures. The difference in preferences of sports venues could have the reason of different supply of sports clubs or the different living standards too. It needs further researches to clear it. Material wealth, income level and sport socialisation can be a determining factor regarding the level of sports spending.

scholarly journals Penis size and sperm quality, are all bats grey in the dark?

2018 ◽  
Vol 65 (6) ◽  
pp. 697-703 ◽  
Author(s):  
Nicolas Jean Fasel ◽  
Marta Kołodziej-Sobocińska ◽  
Ewa Komar ◽  
Marcin Zegarek ◽  
Ireneusz Ruczyński
Keyword(s):  
Sperm Quality ◽  
Copulatory Behavior ◽  
Scaling Relations ◽  
Head Width ◽  
Sperm Velocity ◽  
Selective Pressures ◽  
Penis Size ◽  
Penis Length ◽  
Selection For ◽  
Myotis Nattereri

Abstract Penises play a key role in sperm transport and in stimulating female genitals. This should impact post-copulatory competition, and expose penis characteristics to sexual selective pressures. Studies of male genitalia have repeatedly reported negative static allometries, which mean that, within species, large males have disproportionally small genitals when compared with smaller individuals. Males of some sperm-storing bat species may stand as an exception to such a pattern by arousing from hibernation to copulate with torpid females. The selection for large penises might take place, if a long organ provides advantages during post-copulatory competition and/or if females have evolved mechanisms allowing the choice of sire, relying on characters other than pre-copulatory traits (e.g., penis size). In this study, we measured dimensions of the erected penis in 4 sperm-storing bat species. Furthermore, we collected sperm and evaluated the link between penis dimensions and sperm velocity. Our results revealed steep allometric slopes of the erected penis length in Barbastella barbastellus and an inverse allometry of penis head width in Myotis nattereri. More detailed studies of copulatory behavior are urgently needed to explain the range of observed scaling relations. Furthermore, penis head width correlates with sperm velocity in Plecotus auritus. For this last species, we propose that penis shape might act as a marker of male fertility.

The relationship between forelimb morphology and behaviour in North American carnivores (Carnivora)

1999 ◽  
Vol 77 (7) ◽  
pp. 1064-1074 ◽  
Author(s):  
Andrew N Iwaniuk ◽  
Sergio M Pellis ◽  
Ian Q Whishaw
Keyword(s):  
North American ◽  
Significant Relationship ◽  
Feeding Behaviour ◽  
Prey Capture ◽  
Relative Size ◽  
Independent Contrasts ◽  
Important Indicator ◽  
Predatory Behaviour ◽  
Olecranon Process ◽  
The Relationship

We tested the validity of previously described relationships between forelimb structure and behaviour in mammals by measuring the forelimbs of 22 species of North American carnivores. Nine ratios were calculated from these measurements and made independent of the effects of allometry and phylogeny through the use of log-transformed regressions and independent contrasts analysis. The ratios were then directly compared with two behavioural traits: arboreal locomotion and vertebrate predation. Only five of the nine ratios exhibited a significant relationship with arboreal locomotion and three with vertebrate predation. It was concluded that the brachial index, relative size of the olecranon process, and total forelimb robusticity may be reliable predictors of arboreal locomotion, and that the brachial index, relative size of the olecranon process, and radial robusticity may be accurate predictors of vertebrate predation. The data also suggest that the morphology of the lower forelimb may be an important indicator of prey-capture and feeding behaviour in carnivores and could be used in conjunction with craniodental variables to extrapolate predatory behaviour of extinct species.

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