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Path Velocity (path + velocity)

Distribution by Scientific Domains
Medical Sciences66%

Kinds of Path Velocity

  • average path velocity
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    Selected Abstracts

    Tyrphostin-A47 inhibitable tyrosine phosphorylation of flagellar proteins is associated with distinct alteration of motility pattern in hamster spermatozoa

    MOLECULAR REPRODUCTION & DEVELOPMENT, Issue 2 2006
    Daniel Mariappa
    Abstract To acquire fertilizing potential, mammalian spermatozoa must undergo capacitation and acrosome reaction. Our earlier work showed that pentoxifylline (0.45 mM), a sperm motility stimulant, induced an early onset of hamster sperm capacitation associated with tyrosine phosphorylation of 45,80 kDa proteins, localized to the mid-piece of the sperm tail. To assess the role of protein tyrosine phosphorylation in sperm capacitation, we used tyrphostin-A47 (TP-47), a specific protein tyrosine kinase inhibitor. The dose-dependent (0.1,0.5 mM) inhibition of tyrosine phosphorylation by TP-47 was associated with inhibition of hyperactivated motility and 0.5 mM TP-47-treated spermatozoa exhibited a distinct circular motility pattern. This was accompanied by hypo-tyrosine phosphorylation of 45,60 kDa proteins, localized to the principal piece of the intact-sperm and the outer dense fiber-like structures in detergent treated-sperm. Sperm kinematic analysis (by CASA) of spermatozoa, exhibiting circular motility (at 1st hr), showed lower values of straight line velocity, curvilinear velocity and average path velocity, compared to untreated controls. Other TP-47 analogues, tyrphostin-AG1478 and -AG1296, had no effect either on kinematic parameters or sperm protein tyrosine phosphorylation. These studies indicate that TP-47-induced circular motility of spermatozoa is compound-specific and that the tyrosine phosphorylation status of 45,60 kDa flagellum-localized proteins could be key regulators of sperm flagellar bending pattern, associated with the hyperactivation of hamster spermatozoa. Mol. Reprod. Dev. © 2005 Wiley-Liss, Inc. [source]

    CASA Assessment of Kinematic Parameters of Ram Spermatozoa and their Relationship to Migration Efficiency in Ruminant Cervical Mucus

    REPRODUCTION IN DOMESTIC ANIMALS, Issue 4 2008
    I Robayo
    Contents Sperm motility is an indicator of male fertility because of its importance for sperm migration through the female genital tract and for gamete interaction at fertilization. This study analyses the relationship between computer assisted semen analysis (CASA) motility patterns and sperm migration of rams in ruminant cervical mucus. In experiment 1, spermatozoa extended with sperm analysis medium (SAM) and seminal plasma were compared in terms of motility. In experiment 2, 56 semen samples were collected either with artificial vagina (AV) or electroejaculator to be compared in terms of motility performance. In experiment 3, 104 ejaculates collected by AV from 26 males were analysed via the CASA system to characterize their motility patterns. In experiment 4, ejaculates from pairs of rams (20 rams in total) were simultaneously assessed for mucus migration (ovine, caprine, bovine) and motility patterns to evaluate the correlations between both parameters. Semen collected by AV and extended in SAM allows the most reliable assessment for sperm motility. Ram spermatozoa move fast and follow a linear trajectory compared with other ruminants. Continuous line velocity (VCL) and average path velocity (VAP) are the only sperm kinematic parameters that presented significant positive correlations with the ability to migrate in sheep cervical mucus (p < 0.05). Continuous line velocity, VAP, straight line velocity and linearity are highly significantly related with migration efficiency in goat cervical mucus (p < 0.01) and only lateral head displacement is negatively related to sperm migration in bovine cervical mucus (p < 0.05). These results suggest that specific kinematic parameters confer the ability of spermatozoa to colonize and migrate through epithelial mucus with different rheological properties. [source]

    OC2 Seasonality Affects on Sperm Motility Kinematic Parameters of Murciano-Granadina Bucks

    REPRODUCTION IN DOMESTIC ANIMALS, Issue 2006
    D Abdelwahab
    Four Murciano-Granadina (M-G) bucks were used to study the effect of season (autumn and spring) on semen motility kinematic parameters. Ejaculates (n = 31/season) were collected twice weekly with an artificial vagina and diluted with Tris-based extender (1 : 10). Average path velocity (VAP) and linearity (LIN) were evaluated using a Computer-Assisted Semen Analysis (CASA system). A FASTCLUS procedure was applied to separate spermatozoa into subpopulations based on their motility characteristics. The mean values of both motility kinematic parameters were significantly (p < 0.05) higher in spring than in autumn. Four different motile sperm subpopulations (SP) were identified. In autumn, SP 1 (with a frequency of 17.1%) showed a VAP of 41.5 ,m/s and a LIN of 38.3%. SP 2 (37.2%) a VAP of 70.2 ,m/s and a LIN of 46.1% SP 3 (19.1%) a VAP of 93.3 ,m/s and a LIN of 31.6%. Finally, SP 4 (26.6%) a VAP of 111.8 ,m/s and a LIN of 67.2%. In spring, SP 1 (21.1%) a VAP of 46.3 ,m/s and a LIN of 50.1%. SP 2 (39.6%) a VAP of 77.0 ,m/s and a LIN of 68.6%. SP 3 (17%) a VAP of 87.8 ,m/s and a LIN of 40.2%. Finally, SP 4 (22.3%) a VAP of 112.3 ,m/s and a LIN of 70.4%. In conclusion, the season of ejaculate collection has a significant effect on sperm motility kinematic parameters of M-G bucks. [source]

    CASA-based sperm kinematics of environmental risk factor-exposed human semen samples designated as normozoospermic in conventional analysis

    ANDROLOGIA, Issue 4 2010
    D. Mukhopadhyay
    Summary This study was conducted after an initial epidemiological survey of patients in and around Calcutta, India, concerning their lifestyle history, degree of risk exposure and semen analysis based on conventional WHO criteria. It was found that a large group of exposed patients were showing normozoospermic semen parameters in conventional semen analysis. Hence, a selected group of subjects, designated as normozoospermic in routine analysis, but under risk factor exposure, were selected for a repeat computer aided semen analysis (CASA) and were compared with a control group. The parameters considered among CASA results were: curvilinear velocity (VCL), straight-line velocity, average path velocity (VAP), straightness index (STR), lateral head displacement (ALH) and beat cross frequency. The results depict a significant decline in the mean values of VCL (P = 0.029) and STR (P = 0.007) in the tobacco-exposed group when compared with the unexposed group. On the other hand, there was a significant decline in the mean values of VCL (P = 0.014) and ALH (P = 0.040) in the heavy metal-exposed group when compared with the unexposed group. The other parameters did not show significant change in either group. Semen samples that had been designated normozoospermic in conventional analysis were seen to be influenced by risk factors at the level of sperm motion kinetics. [source]

    Reactivation of motility of demembranated hamster spermatozoa: role of protein tyrosine kinase and protein phosphatases

    ANDROLOGIA, Issue 2 2002
    S. B. Patil
    Summary. Demembranated cauda epididymidal spermatozoa of hamster, following reactivation with 1 mm ATP, exhibited either a loop or planar type of motility. The spermatozoa with planar motility exhibited increased progressive velocity (VSL), straightness (STR), linearity (LIN) and beat cross frequency (BCF) compared to the spermatozoa with loop type motility. cAMP was observed to have differential effects on the motility parameters of the demembranated spermatozoa depending on the type of motility. For instance, in the loop type, average path velocity (VAP), curvilinear velocity (VCL) and VSL were increased in the presence of cAMP unlike in the planar type. Furthermore, in an attempt to understand the role of protein kinases and protein phosphatases in regulation of sperm motility, the effects of various inhibitors of these enzymes on the motility and phosphorylation of proteins of reactivated demembranated spermatozoa were studied. Inhibitors of PTKase (protein tyrosine kinase) and protein phosphatases inhibited the motility of reactivated demembranated hamster spermatozoa. The activity of the respective enzymes associated with demembranated spermatozoa was concurrently inhibited, thus providing evidence that the effect of the inhibitors on motility was mediated through their inhibitory effects on the activities of the enzymes. The results also demonstrated that two phosphotyrosinylated proteins of molecular weight 65 and 80 kDa showed reduced phosphorylation in the presence of PTKase inhibitors, thus indicating their possible role in reactivation of motility of demembranated hamster spermatozoa. [source]

    Cryopreservation of silver barb Puntius gonionotus (Bleeker) spermatozoa: effect of extender composition, cryoprotective agents and freezing rate on their postthawing fertilization ability

    AQUACULTURE RESEARCH, Issue 15 2008
    Padmanav Routray
    Abstract The effects of extender composition, cryoprotectant concentration and freezing and thawing on the fertilization efficiency of cryopreserved spermatozoa of Puntius gonionotus were evaluated. Computer-aided motility analysis of semen was conducted to check the suitability of spermatozoa for cryopreservation after mixing with different extenders and cryoprotective agents (CPAs). Extender-4 with an osmolality 260 mOsmol kg,1and pH 7.6 was used for the cryopreservation study. Among the CPAs, dimethyl sulphoxide (DMSO) was least toxic and more than 60% fertilization was achieved when used at 1.4 M at 0 °C for 10 and 30 min, whereas the toxicity of all CPAs to spermatozoa was evident when tested at 30 °C. Semen frozen at ,16 °C min,1 with 1.4 M DMSO showed 70% fertilization, which was significantly higher (P<0.05) than other freezing rates. Samples thawed at 35 °C water showed a fertilization rate comparable with that of fresh semen. Computer-assisted semen analysis of fresh and frozen semen after thawing showed variations in different types of motility in spermatozoa and in their class. There was no significant difference in motility before or after cryopreservation; however, significant differences could be observed in the average path velocity (VAP), straight line velocity (VSL) and curve linear velocity (VCL). Semen of silver barb could be cryopreserved with extender-4 by addition of 1.4 M DMSO to a final cryopreservation medium (MED 2) cooled at a rate of ,16 °C min,1, stored in liquid nitrogen (,196 °C) and utilized after thawing at 35±2 °C. [source]