head displacement
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2022 ◽  
Vol 21 (1) ◽  
Author(s):  
Wei Wu ◽  
Yiqiu Chen ◽  
Yuting Cheng ◽  
Qiuqin Tang ◽  
Feng Pan ◽  
...  

Abstract Background Several studies have suggested adverse effects of particulate matter (PM) exposure on male reproductive health; few have investigated the association between PM exposure and semen quality in a large population of fertile men. Methods We evaluated 14 parameters of semen quality in 1554 fertile men in Nanjing from 2014 to 2016. Individual exposure to particular matter ≤10 μm in diameter (PM10) and ≤ 2.5 μm in diameter (PM2.5) during key periods of sperm development (0-90, 0-9, 10-14, 15-69, and 70-90 days before semen collection) were estimated by inverse distance weighting interpolation. Associations between PM exposure and semen quality were estimated using multivariable linear regression. Results Higher 90-days average PM2.5 was in association with decreased sperm motility (2.21% for total motility, 1.93% for progressive motility per 10 μg/m3 increase, P <  0.001) and four quantitative aspects of sperm motion (curvilinear velocity (VCL), straight line velocity (VSL), average path velocity (VAP), and amplitude of lateral head displacement (ALH), P <  0.01). The association between PM2.5 exposure and semen quality were generally stronger for the earlier exposure window (70-90 days prior to ejaculation) than for recent exposure (0-9, 10-14, or 15-69 days). In the subgroup of men who had normal sperm parameters (n = 1019), similar results were obtained. Ninety-days PM10 exposure was associated only with decreased VCL and VAP and was not related to sperm concentration. Conclusions Exposure to PM2.5 adversely affects semen quality, specifically lower sperm motility, in fertile men. Graphical abstract


Cells ◽  
2022 ◽  
Vol 11 (2) ◽  
pp. 220
Author(s):  
Ester Sansegundo ◽  
Maximiliano Tourmente ◽  
Eduardo R. S. Roldan

Mammalian sperm differ widely in sperm morphology, and several explanations have been presented to account for this diversity. Less is known about variation in sperm physiology and cellular processes that can give sperm cells an advantage when competing to fertilize oocytes. Capacitation of spermatozoa, a process essential for mammalian fertilization, correlates with changes in motility that result in a characteristic swimming pattern known as hyperactivation. Previous studies revealed that sperm motility and velocity depend on the amount of ATP available and, therefore, changes in sperm movement occurring during capacitation and hyperactivation may involve changes in sperm bioenergetics. Here, we examine differences in ATP levels of sperm from three mouse species (genus Mus), differing in sperm competition levels, incubated under non-capacitating and capacitating conditions, to analyse relationships between energetics, capacitation, and swimming patterns. We found that, in general terms, the amount of sperm ATP decreased more rapidly under capacitating conditions. This descent was related to the development of a hyperactivated pattern of movement in two species (M. musculus and M. spicilegus) but not in the other (M. spretus), suggesting that, in the latter, temporal dynamics and energetic demands of capacitation and hyperactivation may be decoupled or that the hyperactivation pattern differs. The decrease in ATP levels during capacitation was steeper in species with higher levels of sperm competition than in those with lower levels. Our results suggest that, during capacitation, sperm consume more ATP than under non-capacitating conditions. This higher ATP consumption may be linked to higher velocity and lateral head displacement, which are associated with hyperactivated motility.


2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Robin Bishop ◽  
Seok Joon Won ◽  
Karen-Amanda Irvine ◽  
Jayinee Basu ◽  
Eric S. Rome ◽  
...  

AbstractBlast exposure can injure brain by multiple mechanisms, and injury attributable to direct effects of the blast wave itself have been difficult to distinguish from that caused by rapid head displacement and other secondary processes. To resolve this issue, we used a rat model of blast exposure in which head movement was either strictly prevented or permitted in the lateral plane. Blast was found to produce axonal injury even with strict prevention of head movement. This axonal injury was restricted to the cerebellum, with the exception of injury in visual tracts secondary to ocular trauma. The cerebellar axonal injury was increased in rats in which blast-induced head movement was permitted, but the pattern of injury was unchanged. These findings support the contentions that blast per se, independent of head movement, is sufficient to induce axonal injury, and that axons in cerebellar white matter are particularly vulnerable to direct blast-induced injury.


Author(s):  
Alireza Shabanpour ◽  
Mahmoud Ghazavi

The compressive behavior of tapered piles, particularly those with circular cross-sections, has been investigated during the last few decades. However, the tensile behavior of such piles has been rarely studied in the literature. In this paper, 12 static axial tests, including six compressive and also six tensile tests, were performed on instrumented piles with uniform and tapered cross-sections by using a geotechnical centrifuge. Three of the piles had correspondingly circular, square and X-shaped uniform cross-sections along their length, while the other three ones were non-uniform (tapered), all of which had the same length and volume. The results are presented in three main forms: the variation of load versus pile head displacement, the distribution of axial force along the pile length, and the distribution of the unit shaft resistance along the pile length. The behavior of tapered piles is compared with that of uniform cross-section piles. The results confirm the superiority of tapered piles over uniform cross-section piles in terms of load-bearing capacity and construction costs under both tensile and compressive loading.


2021 ◽  
Vol 49 (12) ◽  
pp. 030006052110610
Author(s):  
Hongyan Zhang ◽  
Jun He ◽  
Yili Zhao ◽  
Qifei Wu ◽  
Tiejun Zou ◽  
...  

Objective To investigate the relationship between glutathione S-transferase enzyme ( GSTM1, T1, and P1) genetic variants and semen quality in men with idiopathic infertility. Methods Sperm characteristics were measured using computer-assisted sperm analysis. The malondialdehyde (MDA), nitric oxide (NO), and total antioxidant capacity (TAC) activities were detected by spectroscopic analysis, and 8-hydroxy-2′-deoxyguanosine (8-OHdG) was detected by enzyme-linked immunosorbent assay. Results This study included 246 idiopathic infertile men and 117 controls. The GSTM1(−), T1(−), and M1/T1(−/−) genotype frequencies significantly differed between the groups. The GSTM1(−) and T1(−) genotypes in idiopathic infertile men negatively correlated with sperm concentration, motility, mitochondrial membrane potential, and other parameters. However, these genotypes positively correlated with the amplitude of the lateral head displacement and NO and 8-OHdG levels. The GSTT1(−) genotype positively correlated with mean angular displacement and MDA activity. GSTM1(−) and T1(−) had a synergistic effect on semen quality. Sperm motility, normal morphology, straightness, and TAC were lower and amplitude of lateral head displacement and MDA were higher in the GSTP1(A/G + G/G) group than in the GSTP1(A/A) group among men with idiopathic infertility. Conclusions GSTM1, T1, and P1 genetic variants may be risk factors for infertility by affecting the semen quality men with idiopathic oligoasthenospermia.


2021 ◽  
Vol 22 (23) ◽  
pp. 12646
Author(s):  
Marc Yeste ◽  
Sandra Recuero ◽  
Carolina Maside ◽  
Albert Salas-Huetos ◽  
Sergi Bonet ◽  
...  

Few data exist about the presence and physiological role of Na+/H+ exchangers (NHEs) in the plasma membrane of mammalian sperm. In addition, the involvement of these channels in the ability of sperm to undergo capacitation and acrosomal reaction has not been investigated in any mammalian species. In the present study, we addressed whether these channels are implicated in these two sperm events using the pig as a model. We also confirmed the presence of NHE1 channels in the plasma membrane of ejaculated sperm by immunofluorescence and immunoblotting. The function of NHE channels during in vitro capacitation was analyzed by incubating sperm samples in capacitating medium for 300 min in the absence or presence of a specific blocker (DMA; 5-(N,N-dimethyl)-amiloride) at different concentrations (1, 5, and 10 µM); acrosome exocytosis was triggered by adding progesterone after 240 min of incubation. Sperm motility and kinematics, integrity of plasma and acrosome membranes, membrane lipid disorder, intracellular calcium and reactive oxygen species (ROS) levels, and mitochondrial membrane potential (MMP) were evaluated after 0, 60, 120, 180, 240, 250, 270, and 300 min of incubation. NHE1 localized in the connecting and terminal pieces of the flagellum and in the equatorial region of the sperm head and was found to have a molecular weight of 75 kDa. During the first 240 min of incubation, i.e., before the addition of progesterone, blocked and control samples did not differ significantly in any of the parameters analyzed. However, from 250 min of incubation, samples treated with DMA showed significant alterations in total motility and the amplitude of lateral head displacement (ALH), acrosomal integrity, membrane lipid disorder, and MMP. In conclusion, while NHE channels are not involved in the sperm ability to undergo capacitation, they could be essential for triggering acrosome exocytosis and hypermotility after progesterone stimulus.


2021 ◽  
Author(s):  
Robin Bishop ◽  
Seok Joon Won ◽  
Karen-Amanda Irvine ◽  
Jayinee Basu ◽  
Eric S. Rome ◽  
...  

Abstract Blast exposure can injure brain by multiple mechanisms, and injury attributable to direct effects of the blast wave itself have been difficult to distinguish from that caused by rapid head displacement and other secondary processes. To resolve this issue, we used a rat model of blast exposure in which head movement was either strictly prevented or permitted in the lateral plane. Blast was found to produce axonal injury even with strict prevention of head movement. This axonal injury was restricted to the cerebellum, with the exception of injury in visual tracts secondary to ocular trauma. The cerebellar axonal injury was increased in rats in which blast-induced head movement was permitted, but the pattern of injury was unchanged. These findings support the contentions that blast per se, independent of head movement, is sufficient to induce axonal injury, and that axons in cerebellar white matter are particularly vulnerable to direct blast - induced injury.


Biology ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 595
Author(s):  
Vinicio Barquero ◽  
Eduardo R. S. Roldan ◽  
Carles Soler ◽  
Bernardo Vargas-Leitón ◽  
Francisco Sevilla ◽  
...  

The aim was to determine the relationship between kinematic parameters of boar spermatozoa and fertility rates of sow, as well as to assess the effect of sperm clusters on the fertility capacity of the ejaculate. Semen samples were collected from 11 sexually mature boars. Samples were analyzed by an ISAS®v1 CASA-Mot system for eight kinematic parameters. Ejaculate clusters were characterized using multivariate procedures, such as principal factors (PFs) analysis and clustering methods (the k-means model). Four different ejaculate clusters were identified from two kinematic PFs which involved linear trajectory and velocity. There were differences (p < 0.05) between the sperm kinematic variables by sire line. There was no statistical difference (p > 0.05) between dam lines and ejaculate clusters in fertility variables. The discriminant ability of the different kinematics of sperm variables to predict litter size fertility was analyzed using receiver operating characteristics (ROC) curve analysis. Curvilinear velocity (VCL), average path velocity (VAP), amplitude of lateral head displacement (ALH), and beat-cross frequency (BCF) showed significant, albeit limited, predictive capacity for litter size fertility variables (range: 0.55–0.58 area under curve, AUC). The kinematic analysis of the ejaculates in clusters did not have a predictive capacity for litter size variables.


2021 ◽  
Vol 23 (2) ◽  
pp. 79-91
Author(s):  
Joanna Gradek ◽  
Tomasz Rawo ◽  
Aleksander Psuja ◽  
Karol Gawelowicz ◽  
Jacek Kąpiński ◽  
...  

Background. The purpose of this paper is to evaluate the usefulness of radiographic indices of humero-radial joint instability in order to predict treatment outcomes in Monteggia fractures. Material and methods. A retrospective analysis was conducted in a group of patients who underwent closed reduction and internal titanium elastic nail (TEN) fixation of the ulna and closed reduction of a dislocation of the radial head between 2016 and 2018. The indications for intrame­dullary fixation comprised transverse or short oblique fractures. The direction of the dislocation was classified according to Bado. The following radiographic indies were assessed: Radiocapitellar Line, Lateral Humeral Line, Proximity Index, and Radial Head Displacement Index. Results. Treatment outcomes were assessed with the Oxford Elbow Score and Mayo Elbow Performance Score, and com­plications were assessed with a modified Clavien-Dindo-Sink scale. No coincidence between poor functional and radio­graphic outcomes was demonstrated. Conclusions. 1. Regardless of the severity of the injury, eligibility for surgery and correctly performed surgical treatment guarantee a good final outcome. 2. Patients treated with TEN regain their preoperative mobility. 3. There was no coincidence between poor functional and radiographic outcomes, except for one patient in whom subluxation of the radial head persisted despite surgery and was confirmed radiographically and functionally. 4. It would be beneficial for clinical practice to introduce simple, reproducible radiographic parameters for unambiguous assessment of the effectiveness of treatment and predicting treatment outcomes; unfortunately none of the parameters we investigated were sufficiently reliable. 5. The radiographic parameters analysed in this paper are dependent on the quality of the radiological examinations performed.


Author(s):  
Devangana Chaturvedi ◽  
A.J. Dhami ◽  
D.V. Chaudhari

Background: The evaluation of bull fertility essentially involves semen analysis and conception rates among inseminated females. The conventional evaluation is relatively imprecise, time consuming and subjected to individual variations, while computer assisted sperm analysis (CASA) is a quite faster, precise and objective tool to identify differences in sperm motility and velocity/kinematics attributes and avoids subjective errors. The present study was planned to evaluate and compare the CASA traits of fresh and frozen-thawed semen of Gir and Murrah bulls in Tris extender without and with different antioxidant additives by adopting Biovis CASA.Methods: The semen ejaculates with greater than 75% initial motility from 3 Gir and 3 Murrah bulls were split-diluted at 100 million sperm per ml using Tris-citrate-fructose-yolk-glycerol (TFYG) extender without (control) and with three antioxidant additives, viz., Mifepriston (10 µg/ml), Sericin (5 mg/ml) and Taurine (4 mg/ml), were filled in French mini straws and frozen in liquid nitrogen vapour using a programmable biofreezer. The freshly diluted and frozen-thawed semen samples were assessed for sperm motion characteristics, velocity/kinematics using Biovis CASA. Result: The mean percentages of total motile spermatozoa, irrespective of additives, in freshly diluted and frozen-thawed semen were 85.50±0.92 and 48.76±1.69 for Gir bulls and 85.03±0.72 and 52.61±1.46 for Murrah bulls, respectively. The mean total motile as well as rapid and slow progressive motile sperm percentage were significantly enhanced by fortification of TFYG extender with Mifepristone than in control extender, while values for Sericin and Taurine were intermediary and statistically similar to Mifepristone. The per cent decline in total motile sperm due to freezing-thawing was more or less same in both the breeds for all the extender additives, being lowest in Mifepristone supplemented extender in cattle (32.27 vs 48.81%) and buffalo (31.27 vs 43.14%) semen. The rapid and slow progressive motile sperm also followed the same pattern. The values of VAP and VCL were significantly (p less than 0.05) higher and VSL lower in Murrah than Gir breed at post-thaw stage. The overall mean linearity (%), straightness (%), beat-cross frequency (hz), lateral head displacement (µm), wobbling index (%), dancing velocity (µm2/s) and dancing mean (µm2/s) of sperm were higher in Murrahs than in Gir semen with significant (p less than 0.01) difference at post-thaw stage. The fortification of extender with Mifepristone improved all these traits at post-thaw stage compared to other additives and control TFYG extender. The per cent decline in these traits due to freezing stress was much lower in buffalo sperm than the cattle sperm particularly with Mifepristone fortification. It was concluded that freezing-thawing stress adversely affected the motion and kinematics of both cattle and buffalo sperm and that Tris extender fortified with antioxidant additives, particularly Mifepristone @ 10 µg/ml, protected sperm from adverse effect of dilution and cryopreservation with improved post-thaw sperm quality.


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