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At least 19 recordsLinked to original sources
PubMed1979

Factors affecting sperm motility. I. In vitro change in motility with time after ejaculation.

Semen specimens from 33 donors were analyzed intermittently between 1 and 24 hours after ejaculation. Motility was determined objectively by analyzing still-camera photomicrographs taken with the aid of the new multiple exposure photography (MEP) technique, from which the following information was obtained: the percentage of motile spermatozoa, the average velocity and frequency distribution of spermatozoal velocities, and index of motility as well as sperm concentration. From curves drawn for each of the 33 analyzed specimens, these conclusions were drawn: 1. The percentage of motile spermatozoa decreases progressively, beginning 1 hour after ejaculation, at a rate of about 5% to 10%/hour. 2. In the majority of cases, sperm velocity increases for the first 4 hours and then decreases gradually. 3. There is no unique pattern of sperm motility and velocity with time for all specimens, especially during the first 4 hours. However, three typical curves of motility change were found during the first 4 hours: increase in motility, moderate decline in motility, and rapid loss of motility. 4. The frequency distribution of velocities of motile spermatozoa revealed typical normal curves at all times, but these curves became flatter as time elapsed. An explanation for these divergent patterns and the possible role of these findings in some physiologic and clinical problems are discussed.

Ejaculation↗
PubMed2026

Motile and non-motile Listeria species adopt distinct ecological and evolutionary strategies to achieve broad geographic ranges across soil ecosystems.

Broad geographic ranges often reflect ecological versatility and are associated with lower extinction risk. Motility is a key physiological and ecological trait in bacteria. However, how some motile and non-motile bacteria achieve broad geographic ranges remains poorly understood. Here, we analyzed the genomes of 141 Listeria welshimeri and 90 Listeria booriae isolates systematically obtained from soils, representing widespread motile and non-motile species, respectively. We show that L. welshimeri lacks clear phylogeographic structure, suggesting minimal geographic barriers to dispersal. Its wide distribution is likely associated with enhanced motility and effective host colonization that facilitate wildlife-driven dispersal, particularly by regional-terrestrial birds. This pattern is supported by positive selection on flagellar and chemotaxis genes, strong associations with wildlife movement patterns, and close genomic relatedness between soil and wild bird isolates. In contrast, L. booriae displays clade endemism and a strong distance-decay relationship, suggesting dispersal limitation. Despite lacking a dispersal advantage, L. booriae's wide distribution appears to be linked to genomic flexibility and metabolic versatility that support adaptation to diverse environmental conditions, especially those shaped by iron concentration and precipitation. This is evidenced by its large, open pangenome characterized by abundant and diverse metabolic pathways and broad substrates utilization capacity; pronounced positive selection on genes involved in inorganic ion, amino acid, and coenzyme transport and metabolism; and strong associations between gene richness and abiotic factors as well as bacterial community composition. These findings suggest distinct genomic foundations and ecological and evolutionary mechanisms underlying the success of motile and non-motile cosmopolitan bacteria in soil ecosystems.

Soil Microbiology↗
PubMed1979

Factors affecting sperm motility. II. Human sperm velocity and percentage of motility as influenced by semen dilution.

Spermatozoal velocity and percentage of motility were analyzed objectively with the multiple exposure photography method before and after specimens from fertile and infertile men were diluted in their own seminal plasma or normal saline. No significant change in percentage of motility was found in samples diluted up to 1:6 in both kinds of diluents. However, a significant relative increase (up to 25% of the original velocity) was found when a specimen was diluted with its own seminal plasma, and an even greater increase (up to 37% of the original velocity) was found when it was diluted with saline. Compared with undiluted specimens, there was no delayed effect on spermatozoal motility when semen was diluted with saline after up to 4 hours' incubation time. Contrary to the findings in animal and human semen described by others, there was no deleterious effect on sperm motility with this kind and rate of dilution and duration of time. The assumption that the increase in sperm velocity caused by dilution is not excitatory but is due only to a decrease of seminal fluid viscosity and a reduced number of spermatozoa which interfere with sperm free movement is discussed. We recommend evaluation of spermatozoal motility in diluted specimens in addition to evaluation of the original specimen in any routine semen analysis in order to determine true spermatozoal motility potential under optimal conditions.

Culture Media↗
PubMed1976

Improved motility recovery of human spermatozoa after freeze preservation via a new approach.

A new sperm isolation technique was studied in conjunction with the short-term freeze preservation of human spermatozoa. The isolation procedure yielded subpopulations of spermatozoa with very high percentage motility and progressive motility score, and which were virtually free of seminal debris. For 24 semen samples from 13 donors, the mean prefreeze values of percentage motility and motility score were 53% (2.8), 73% (3.1), and 88% (3.5) for the parent semen, 7.5% BSA (middle) fractions, and 17.5% BSA (bottom) fractions, respectively. These samples were used without a priori constraint on semen quality. Eleven samples were preselected on the basis of good motility in the semen. These yielded prefreeze motility values of 66% (3.2), 70% (3.4), and 87% (3.9) for the semen and two fractions, respectively. Sperm motility in the middle fractions was thus intermediate to that in the semen and in the bottom fractions, although closer to the former in these 11 cases. The sperm freeze preservation procedure involved dilution of the semen samples and separated sperm fractions with a cryoprotective semen extender, and freezing and thawing in a conventional manner. Post-thaw percentage motility, motility score, and percentage survival were substantially higher for the separated fractions than for the parent semen. For the 24 cases, the bottom fractions yielded mean values of 57% motility, 3.0 motility score, and 70% survival, in comparison with the respective values of 20%, 2.3, and 34% for the semen. In the 11 preselected cases, the bottom fractions yielded post-thaw mean values of 60% motility, 3.3 motility score, and 72% survival; the middle fractions yielded respective values of 45%, 3.1, and 64%; and the parent semen yielded respective values of 27%, 2.3, and 41%. It was concluded that the major factor in improving post-thaw motility recovery was the separation process as a whole, rather than the degree of separation.

Cell Separation↗
PubMed1975

Motility of Bacillus subtilis during growth and sporulation.

The change of motility and the presence of flagella were followed throughout growth and sporulation in a standard sporulating strain and in 19 cacogenic sporulation mutants of Bacillus subtilis. For the standard strain, the fraction of motile cells decreased during the developmental period to less than 10% at T4. Motility was lost well before the cells lose their flagella. Conditions reducing the decrease of motility also reduced sporulation: motile cells never contained spores. The decrease of motility was not coupled with a decrease in the cellular concentration of adenosine 5'-triphosphate or a decline in oxygen consumption, but an uncoupling agent immediately destroyed motility at any time. Apparently, motility decreased during development because it became increasingly uncoupled from the energy generating systems of the cell. The motility of sporulation mutants decreased after the end of growth at the same time as or earlier than the motility of the standard strain; the early decrease of motility in an aconitase mutant, but not that in an alpha-ketoglurate dehydrogenase mutant, could be avoided by addition of L-glutamate. Sporulation or related events such as extracellular antibiotic or protease production were not needed for the motility decline.

Adenosine Triphosphate↗
PubMed1976

Human lymphocyte motility: normal characteristics and anomalous behavior of chronic lymphocytic leukemia cells.

The characteristics of human lymphocyte motility and its relationship to the redistribution of surface membrane antigens (capping) are poorly defined. Since chronic lymphocytic leukemia (CLL) cells cap poorly when compared with normal human lymphocytes, this study was undertaken to compare the motility of these two cell types. A modification of the Boyden chamber system was employed to quantify lymphocyte motility by placing lymphocyte suspensions on 8-mum convoluted-pore nitrocellulose filters and measuring the depth of migration of the cells into the filter at 37 degrees C. After 3 hr of incubation, CLL cells migrated significantly less into the filter than normal cells. Incubation in the presence of sodium azide or at 4 degrees C abolished all motility, indicating the active nature of the process. The relative motility of individual CLL patients' cells correlated best with the proportion of abnormal cells present as determined by surface receptor assays. The possibility that decreased cell motility in CLL was a reflection of enrichment by a "bone marrow-derived" (B cell) population was eliminated by the finding that normal B cells purified by gradient separation of rosetted cells migrated faster than normal T cells and considerably faster than CLL cells. Motility of normal and CLL lymphocytes was decreased by cytochalasin B and increased by colchicine, vincristine, and vinblastine. Thus, human lymphocyte motility appears to be dependent on microfilament integrity but not to require the colchicine-sensitive cytoskeleton. The decreased motility of CLL cells is the result of an intrinsic cell abnormality, but this finding cannot fully explain the decreased capping, since in human lymphocytes the latter is not prevented by an inhibitor of motility.

Adult↗
PubMed1978

Sperm motility within the mammalian epididymis: species variation and correlation with free calcium levels in epididymal plasma.

The region within the epididymis where spontaneous sperm motility first appeared and the extent of later motility within that organ, as shown by microscopic observation of undiluted samples, varied with the species. In the rat, mouse, and hamster, little sperm motility was present. In other species, spontaneously motile sperm were obtained from the caput (rabbit) and corpus (bull and man) regions of the epididymis. Samples from the cauda region of the epididymis were found to contain many motile sperm in the rabbit, bull, and especially man, where most of the sperm were intensely motile. There was a correlation between the amount of free calcium surrounding the sperm within the cauda epididymidis of a given species and the level of sperm motility therein. An inverse relationship was also found between the free calcium concentration in the cauda epididymal plasma of a species and the later inducibility of motility in diluted sperm from that species by calcium ion.

Animals↗
PubMed1979

Neural mechanisms of reflex facilitation and inhibition of gastric motility to stimulation of various skin areas in rats.

1. Experiments were performed on chloralose-urethane anaesthetized rats to determine the involvement of extrinsic gastric autonomic nerves in reflex facilitation and inhibition of gastric motility when mechanical nociceptive stimulation was delivered to either hind paw or abdominal skin, respectively. 2. After bilaterally sectioning the splanchnic nerves in vagal intact animals, the reflex facilitation of gastric motility produced by hind paw stimulation persisted, but the reflex inhibition previously produced by abdominal skin stimulation disappeared. 3. Hind paw stimulation increased efferent activity of the gastric branch of the vagus nerve, but stimulation of abdominal skin had little influence. 4. Bilateral vagotomy in splanchnic nerve intact animals did not influence the gastric reflex inhibition by abdominal skin stimulation, but either abolished gastric reflex facilitation produced by hind paw stimulation or reversed the reflex facilitation response to slight reflex inhibition. 5. Efferent activity of the gastric sympathetic nerve was greatly increased by abdominal skin stimulation, and was either slightly increased or not influenced by hind paw stimulation. 6. It was concluded that reflex increase of efferent activity of the gastric vagi was responsible for the gastric motility facilitation produced by hind paw stimulation, and also that reflexly increased efferent activity of the gastric sympathetic nerves resulted in gastric motility inhibition produced by abdominal skin stimulation. It is suggested efferents are inhibitory. 7. After spinal transection at the cervical level, the reflex facilitation of gastric motility previously produced by stimulation of a hind paw was completely abolished, or reversed to slight reflex inhibition, while reflex inhibition of gastric motility produced by stimulation of abdominal skin remained. It was concluded that the gastric reflex inhibition was a spinal reflex. 8. Interaction between reflex facilitation and inhibition of gastric motility during simultaneous stimulation of both hind paws and abdominal skin was observed as partial cancellation of each effect by the other. However, sympathetic reflex inhibition of gastric motility seemed to be much stronger than the vagal reflex facilitatory effect.

Animals↗
PubMed1979

Elimination of errors induced during a routine human sperm motility analysis.

Influence of some variables on the accuracy of sperm motility evaluation was studied by analyzing normal seminal specimens with the aid of themultiple exposure photography (MEP) method. Results of this study demonstrated the existence of variations in sperm motility between view areas of the same sample or between different samples of the same specimen. Variations were found even when the same view area was analyzed intermittently during a short period of time. Motility was practically unaffected when a regular sized drop was kept within the preparation for about 20 min. The light from the microscope neither stimulated nor depressed sperm motility when they were illuminated continuously for that period of time. Percent of motility and sperm velocity was directly related to the thickness of the examined drop when the latter ranged between zero and ten micrometers. According to these findings it is suggested that several view areas from various drops of the same specimen should be analyzed with each view area being inspected several times before motility of that field is assessed. Motility should be evaluated from drops of standard and constant thickness; otherwise major errors in sperm motility assessment are to be expected.

Diagnostic Errors↗
PubMed1976

Adenine nucleotide changes at initiation of bull sperm motility.

Testicular and cauda epididymal sperm were obtained via catheters previously implanted in the rete testis and proximal vas deferens of bulls and were used to examine the relationships among sperm motility, cyclic adenosine 3':5'-monophosphate (cAMP) level, adenine nucleotide levels, and rates of glucose and oxygen consumption. Testicular, cauda epididymal, and ejaculated sperm contain cAMP-stimulated protein kinase, adenylate cyclase, and nucleotide phosphodiesterase. Treatment of the nonmotile testicular sperm with phosphodiesterase inhibitors resulted in a doubling of cellular cAMP concentration and a 25% increase in their glucose consumption. No change in motility, ATP level, or rate of oxygen consumption was observed. Sperm in neat cauda epididymal semen had flagellating tails but no progressive motility. Dilution of these sperm into glucose-containing buffer resulted in an increase in intracellular cAMP concentration and a decrease in ATP level with concomitant increases in ADP and AMP levels. These biochemical changes occurred within 30 s after dilution and apparently preceded the initiation of progressive motility by most cells. Since sperm in neat cauda epididymal semen became progressively motile when diluted with neat cauda epididymal plasma as well as accessory sex gland fluid or buffer, composition of the fluid surrounding the sperm is not responsible for the initiation of progressive motility upon dilution nor does cauda epididymal plasma contain an inhibitory factor. Perhaps release from contact immobilization provides the stimulation for the initial acquisition of progressive motility by cauda epididymal sperm. We conclude that during epididymal passage sperm develop from a cell physically unresponsive to changes in cAMP concentration to a form which initiates progressive motility upon changes in cAMP concentration.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1978

Bovine sperm forward motility protein. Partial purification and characterization.

A protein, present in bovine seminal plasma, initiates forward motility in immature, immotile caput spermatozoa that have been incubated with a cyclic AMP phosphodiesterase inhibitor. An improved motility assay was developed to study this process and the protein involved. This forward motility protein exhibits multiple forms when fractionated on the basis of charge or molecular weight. Molecular sieving in urea or sodium dodecyl sulfate and dithiothreitol results in a single peak of activity which will re-form the larger aggregates in the absence of these agents. The molecular weight of this monomeric motility protein, as estimated from molecular sieving under these dissociating conditions, is 37,500. The forward motility protein can be partially purified by heat treatment, gell chromatography in urea, and affinity chromatography on concanavalin A/agarose. Enzymatic treatments further suggest a glycoprotein nature, i.e. treatment with beta-galactosidase, neuraminidase, alpha-mannosidase, or galactose oxidase reduces its activity by 50%; treatment with trypsin completely abolishes forward motility protein activity. On the basis of concurrent studies on the activity, properties, and distribution of forward motility protein in bovine body fluids, it is suggested that this protein is involved in the development of the capacity for motility as sperm traverse the epididymis.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1976

The effects of alkalinity and hypertonicity on the morphology and motility of Leptospira interrogans (biflexa) strain B16.

Effects of alkalinity and hypertonicity on the motile behaviour of Leptospira interrogans (biflexa) B16 were observed, quantified, and compared with effects previously shown by similar factors on the motility of eubacteria. Leptospira interrogans tolerated relatively high concentrations of hydroxide ions. Motility similar to that in controls was observed at pH values up to 9-8; but at pH 10-0 motility declined sharply with time of exposure, and there was structural alteration, visible as a blebbing of the cell envelope. Unlike the behaviour of eubacteria, immobilization of L. interrogans induced by hydroxide ions could not be reversed by lowering the pH. It is suggested that by restricting entry of hydroxide ions, the cell envelope protects its motility apparatus from adverse effects. Leptospira interrogans was completely immobilized in 0-5 M and 1-0 M-sucrose solutions. Unlike the eubacteria, leptospires were incapable of spontaneous reversion to motile forms and resumption of motility was dependent on both concentration and time of exposure to sucrose. Deuterium oxide did not affect movement, suggesting that even though leptospire endoflagella and the exoflagella of eubacteria are analogous, the motile behaviour of L. interrogans is significantly different from that of eubacteria.

Culture Media↗
PubMed1979

Characteristics of individual polymorphonuclear leucocyte motility obtained with a new opto-electronic method.

An opto-electronic device has been used for a quantitative assessment of the motility of individual polymorphonuclear leucocytes (PMNL) adhering to a glass cover slip. One of the oculars in a phase contrast microscope is provided with a mini-array of 32 x 32 light-sensitive elements. These are connected to an electronic unit, capable of recording the number of light-intensity changes on each element and of visualizing the path of a cell on an oscilloscope screen, as a pattern of dots. The results clearly show that individual PMNL respond differently to environmental conditions; for instance, (i) raising the temperature increased the motility of cells to a maximum at around 39 degrees C and lowering the temperature from 42 degrees C restored their peak motility, (ii) protein was required at attachment depending on the temperature at attachment, (iii) endotoxin-activated normal human serum affected more drastically cells with a low initial motility and cytochalasin B more adversely influenced cells with a high initial motility, (iv) phagocytosis of yeast cells reduced the percentage of motile cells, which was more pronounced if the PMNL were washed before the motility measurement. The average motility of the PMNL was also diminished, although individual PMNL retained normal activity after ingestion of one or more yeast cells.

Animals↗