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Motility Characteristics (motility + characteristic)

Distribution by Scientific Domains

Medical Sciences	70%
Life Sciences	20%

Selected Abstracts

Autologous Whole Ram Seminal Plasma and its Vesicle-free Fraction Improve Motility Characteristics and Membrane Status but not In Vivo Fertility of Frozen,Thawed Ram Spermatozoa

REPRODUCTION IN DOMESTIC ANIMALS, Issue 5 2007
R El-Hajj Ghaoui
Contents Motility characteristics (assessed subjectively and with computer-assisted semen analysis) and membrane status (after staining with chlortetracycline) of washed and non-washed frozen,thawed ram spermatozoa were evaluated after incubation in buffer and buffer containing autologous whole seminal plasma or one of its two fractions: the pellet of membrane vesicles obtained by ultracentrifugation (and used at three times normal protein concentration) or the vesicle-free supernatant fraction. Whole seminal plasma and supernatant, but not membrane vesicles, improved the motility characteristics of spermatozoa after 3 and 6 h of post-thaw incubation compared with the control buffer. Resuspension and incubation with whole seminal plasma, supernatant or membrane vesicles lowered the proportion of acrosome-reacted frozen,thawed spermatozoa compared with the control buffer. Unwashed frozen,thawed semen from three rams, incubated with autologous whole seminal plasma or its fractions and inseminated using cervical or intrauterine artificial insemination, had no effect on pregnancy rates of ewes in synchronized oestrus. However, fertility was higher after laparoscopic than cervical insemination (44.9 vs 12.3%, p < 0.001). In conclusion, resuspension and incubation of frozen,thawed ram spermatozoa in autologous whole seminal plasma or its vesicle-free supernatant fraction improved their motility characteristics and, with membrane vesicles, membrane status, but these benefits were not reflected in improved fertility after cervical or intrauterine insemination. [source]

Symmetry-breaking in mammalian cell cohort migration during tissue pattern formation: Role of random-walk persistence

CYTOSKELETON, Issue 4 2005
S. Huang
Abstract Coordinated, cohort cell migration plays an important role in the morphogenesis of tissue patterns in metazoa. However, individual cells intrinsically move in a random walk-like fashion when studied in vitro. Hence, in the absence of an external orchestrating influence or template, the emergence of cohort cell migration must involve a symmetry-breaking event. To study this process, we used a novel experimental system in which multiple capillary endothelial cells exhibit spontaneous and robust cohort migration in the absence of chemical gradients when cultured on micrometer-scale extracellular matrix islands fabricated using microcontact printing. A computational model suggested that directional persistence of random-walk and dynamic mechanical coupling of adjacent cells are the critical control parameters for this symmetry-breaking behavior that is induced in spatially-constrained cell ensembles. The model predicted our finding that fibroblasts, which exhibit a much shorter motility persistence time than endothelial cells, failed to undergo symmetry breaking or produce cohort migration on the matrix islands. These findings suggest that cells have intrinsic motility characteristics that are tuned to match their role in tissue patterning. Our results underscore the importance of studying cell motility in the context of cell populations, and the need to address emergent features in multicellular organisms that arise not only from cell-cell and cell-matrix interactions, but also from properties that are intrinsic to individual cells. Cell Motil. Cytoskeleton 61:201,213, 2005. © 2005 Wiley-Liss, Inc. [source]

The in vitro influences of neurotensin on the motility characteristics of human U373 glioblastoma cells

NEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 6 2006
S. Servotte
Astrocytic tumours are associated with dismal prognoses due to their pronounced ability to diffusely invade the brain parenchyma. Various neuropeptides, including gastrin, are able to modulate tumour astrocyte migration. While neurotensin has been shown to influence the proliferation of glioma cells and the migratory ability of a large set of other cell types, its role in glioma cell migration has never been investigated. Neurotensin-induced modifications to the motility features of human U373 glioblastoma cells therefore constitute the topic of the present study. We evidenced that three subtypes of neurotensin receptors (NTR1, NTR2 and NTR3) are expressed in U373 glioblastoma cells, at least as far as their mRNAs are concerned. Treating U373 tumour cells with 10 nM neurotensin markedly modified the morphological patterns of these cells and also profoundly altered the organization of their actin cytoskeletons. Pull-down assays revealed that neurotensin induced the activation in U373 cells of both Rac1 and Cdc42 but not RhoA. Scratch wound assays evidenced that neurotensin (0.1 and 10 nM) very significantly inhibited wound colonization by U373 cells cultured in the absence of serum. In addition, quantitative phase-contrast videomicroscopy analyses showed that neurotensin decreases the motility levels of U373 glioblastoma cells when these cells are cultured on plastic. In sharp contrast, neurotensin stimulates the motility of U373 cells when they are cultured on laminin, which is a pro-adhesive extracellular matrix component ubiquitously secreted by glioma cells. Our data thus strongly suggest that, in addition to gastrin, neurotensin is a neuropeptide capable of modulating tumour astrocyte migration into the brain parenchyma. [source]

Autologous Whole Ram Seminal Plasma and its Vesicle-free Fraction Improve Motility Characteristics and Membrane Status but not In Vivo Fertility of Frozen,Thawed Ram Spermatozoa

Multivariate Cluster Analysis Regression Procedures as Tools to Identify Motile Sperm Subpopulations in Rabbit Semen and to Predict Semen Fertility and Litter Size

REPRODUCTION IN DOMESTIC ANIMALS, Issue 3 2007
A Quintero-Moreno
Contents Computerized motility analysis (CASA) shows that four separate subpopulations of spermatozoa with different motility characteristics co-exist in rabbit ejaculates. There were significant (p < 0.01) differences in the distribution of these subpopulations among separate genetic lines, total sperm abnormalities and the percentage of altered acrosomes. Furthermore, logistic and linear multivariate regressions among several parameters of rabbit semen quality analysis were tested for use as predictive tools for the fertilizing ability of a specific artificial insemination semen sample. Logistic regression analysis rendered two mathematical, significant (p < 0.01) models: one between sperm viability and conception rate and the other between total sperm abnormalities and conception rate. Multiple linear regression analyses also yielded some significant relationships between both fertility (p < 0.001) and litter size (p < 0.05), with respect to some semen characteristics. Our results support the hypothesis that the predictive in vivo fertility use of the standard rabbit semen quality analysis coupled with a CASA determination could be reasonably achieved by applying linear and logistic regression analyses among several parameters of rabbit semen quality analysis. [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]

In vitro Capacitation and Acrosome Reaction of Dog Spermatozoa can be Feasibly Attained in a Defined Medium Without Glucose

REPRODUCTION IN DOMESTIC ANIMALS, Issue 3 2004
JL Albarracín
Contents Incubation of dog spermatozoa in a medium without glucose and in the presence of lactate and pyruvate (l-CCM) for 4 h at 38.5°C in a 5% CO2 atmosphere induced in vitro capacitation of these cells. This was verified after the combined specific capacitation-like changes in percentages of viability and altered acrosomes, motility characteristics, sperm location of reactivity against Pisum sativum, Arachis hypogaea and Helix pomatia lectins and the tyrosine phosphorylation pattern. Furthermore, a feasible acrosome reaction (AR) was induced when spermatozoa incubated in l-CCM for 4 h were further co-incubated for 1 h with canine oocytes. This was demonstrated by AR-like changes in percentages of viability, altered acrosomes, motility characteristics and sperm location of reactivity against P. sativum, A. hypogaea and H. pomatia lectins. All these results clearly indicate that in vitro capacitation, and subsequent AR, can be feasibly achieved without the presence of sugars. This ability can be related to the specific characteristics of energy-metabolism regulation reported in dog spermatozoa. [source]

Sperm motility and fertilizing ability in the Persian sturgeon Acipenser persicus

AQUACULTURE RESEARCH, Issue 9 2005
Sayyed Mohammad Hadi Alavi
Abstract The motility and fertilizing ability of the Persian sturgeon, Acipenser persicus, spermatozoa were investigated. Optimum ionic content (Na+, K+, Ca2+ and Mg2+) and pH of activation solution as well as the optimum dilution rate were determined. The results show optimum motility characteristics of spermatozoa in buffered solutions containing 25, 0.2, 3 and 10 mM L,1 Na+, K+, Ca2+ and Mg2+, respectively, at dilution rate 1:50 and pH 8.0. To test the fertilizing ability of sperm, two buffered saline solutions were used as activation solution of sperm motility. The present study indicated (1) spermatozoa motility is one of key factors that influence on fertilizing ability of sperm, (2) a high fertilizing ability of sperm is obtained after dilution in saline solutions rather than in freshwater and (3) a maximum fertilization rate occurs in buffered saline solution containing 0.2 mM L,1 K+. There is also a good correlation between biochemical characteristics of seminal plasma and fertilizing ability of sperm. [source]

Directed attachment of antibodies to kinesin-powered molecular shuttles

BIOTECHNOLOGY & BIOENGINEERING, Issue 6 2009
Amanda Carroll-Portillo
Abstract Biomolecular motors, such as kinesin, have been used to shuttle a range of biological and synthetic cargo in microfluidic architectures. A critical gap in this technology is the ability to controllably link macromolecular cargo on microtubule (MT) shuttles without forming extraneous byproducts that may potentially limit their application. Here we present a generalized approach for functionalizing MTs with antibodies in which covalent bonds are formed between the carbohydrate in Fc region of polyclonal antibodies and the positively charged amino acids on the MT surface using the crosslinker succinimidyl 4-hydrazidoterephthalate hydrochloride (SHTH). Antibody-functionalized MTs (Ab-MTs) produced through this approach maintained motility characteristics and antigenic selectivity, and did not produce undesirable byproducts common to other approaches. We also demonstrate and characterize the application of these Ab-MTs for capturing and transporting bacterial and viral antigens. While this approach cannot be applied to monoclonal antibodies, which lack a carbohydrate moiety, it may be used for selectively functionalizing MT shuttles with a variety of carbohydrate-containing cargoes. Biotechnol. Bioeng. 2009; 104: 1182,1188. © 2009 Wiley Periodicals, Inc. [source]