Ultrastructure and motility pattern of the spermatozoa of Aleochara curtula (Coleoptera, Staphylinidae)

2002 ◽  
Vol 31 (3) ◽  
pp. 243-254 ◽  
Author(s):  
Michael Werner ◽  
Thomas Tscheulin ◽  
Thomas Speck ◽  
Dieter Zissler ◽  
Klaus Peschke
Keyword(s):  
Motility Pattern ◽  
Aleochara Curtula

scholarly journals Cooperation of two opposite flagella allows high-speed swimming and active turning in zoospores

2021 ◽  
Author(s):  
Quang D. Tran ◽  
Eric Galiana ◽  
Philippe Thomen ◽  
Céline Cohen ◽  
François Orange ◽  
...  
Keyword(s):  
Host Plant ◽  
High Speed ◽  
Plant Pathogens ◽  
Plant Diseases ◽  
Active Process ◽  
Motility Pattern ◽  
Anterior Flagellum ◽  
Active Turning ◽  
Posterior Flagellum ◽  
Run And Tumble

Phytophthora species cause diseases in a large variety of plants and represent a serious agricultural threat, leading, every year, to multibillion dollar losses. Infection occurs when these biflagellated zoospores move across the soil at their characteristic high speed and reach the roots of a host plant. Despite the relevance of zoospore spreading in the epidemics of plant diseases, it is not known how these zoospores swim and steer with two opposite beating flagella. Here, combining experiments and modeling, we show how these two flagella contribute to generate thrust when beating together, and identify the mastigonemes-attached anterior flagellum as the main source of thrust. Furthermore, we find that steering involves a complex active process, in which the posterior flagellum is stopped, while the anterior flagellum keeps on beating, as the zoospore reorients its body. Our study is a fundamental step towards a better understanding of the spreading of plant pathogens’ motile forms, and shows that the motility pattern of these biflagellated zoospores represents a distinct eukaryotic version of the celebrated “run-and-tumble” motility class exhibited by peritrichous bacteria.

scholarly journals (Gln4)-Neurotensin Changes the Motility Pattern of the Duodenum and Proximal Jejunum From a Fasting-Type to a Fed-Type

1982 ◽  
Vol 83 (3) ◽  
pp. 569-574 ◽  
Author(s):  
Kjell Thor ◽  
Sune Rosell ◽  
Åke Rökaeus ◽  
Lars Kager
Keyword(s):  
Proximal Jejunum ◽  
Motility Pattern

Sugar Concentration of the Freezing Extender Modulates the Motility Pattern of Frozen-Thawed Boar Spermatozoa.

2008 ◽  
Vol 78 (Suppl_1) ◽  
pp. 225-225
Author(s):  
Jordi Roca ◽  
Marta Hernandez ◽  
Teresa Cremades ◽  
Juan Vazquez ◽  
Emilio Martinez
Keyword(s):  
Sugar Concentration ◽  
Motility Pattern ◽  
Boar Spermatozoa

Influence of substance P on myoelectric activity of the small bowel

1982 ◽  
Vol 243 (6) ◽  
pp. G493-G496 ◽  
Author(s):  
P. J. Thor ◽  
R. Sendur ◽  
S. J. Konturek
Keyword(s):  
Small Bowel ◽  
Substance P ◽  
Intestinal Motility ◽  
Conscious Dogs ◽  
Myoelectric Activity ◽  
Stimulatory Action ◽  
Motility Pattern ◽  
Small Doses ◽  
Silver Electrodes ◽  
Higher Doses

The effects of substance P (SP) on intestinal myoelectric activity were examined in conscious dogs with implanted silver electrodes on the small doses (0.25-1.0 nmol . kg-1 . h-1) raised the frequency of interdigestive myoelectric complexes and also increased preburst activity, mostly in the upper small bowel. The ileum was relatively less sensitive to the stimulatory action of sp. At higher doses (2.04.0 nmol . kg-1 . h-1) SP caused a fedlike motility pattern. In the doses used SP did not change the foodinduced motility pattern. The effects of SP on myoelectric activity were blocked by atropine or pirenzepine. We conclude that SP was participate in neurally mediated changes in intestinal motility.

Effect of ileal infusion of lipid on jejunal motor patterns after a nutrient and nonnutrient meal

1988 ◽  
Vol 255 (6) ◽  
pp. G800-G806 ◽  
Author(s):  
I. M. Welch ◽  
P. A. Davison ◽  
J. Worlding ◽  
N. W. Read
Keyword(s):  
Small Intestine ◽  
Small Bowel ◽  
Contraction Rate ◽  
Small Bowel Transit ◽  
Motor Patterns ◽  
Motility Pattern ◽  
Human Small Intestine ◽  
The Mean

To investigate how ileal lipid delays small bowel transit, pressure activity was recorded at multiple sites in the human small intestine during ileal infusion of either lipid or saline. Initial studies showed that ileal lipid reduced the contraction rate in the jejunum but not in the duodenum or ileum. The effect of ileal lipid was further investigated by recording pressures at seven sites in the jejunum after ingestion of either a nutrient or a nonnutrient meal. The nutrient meal induced an irregular motility pattern; ileal lipid significantly reduced the contraction rate, the percentage of contractions involved in propagated events, the mean length of propagation, and the propagation index. The nonnutrient meal induced a pattern containing discrete clusters of contractions. Ileal lipid significantly reduced the occurrence of contraction clusters and the mean length of propagation. Thus, although the delay in small bowel transit observed during ileal infusion of lipid can be explained by reductions in the rate and the degree of propagation of jejunal contractions, the mechanism varies according to the type of meal.

Novel telemetric system for extraluminal measurement of gastrointestinal motility

1976 ◽  
Vol 41 (3) ◽  
pp. 425-428 ◽  
Author(s):  
N. L. Shearin ◽  
C. J. Pfeiffer ◽  
S. Kilam
Keyword(s):  
Gastrointestinal Tract ◽  
Motor Function ◽  
Gastrointestinal Motility ◽  
Motility Pattern ◽  
Intravenous Injections ◽  
In Vivo Measurement ◽  
Meat Meal ◽  
Telemetric System ◽  
Small Intestinal

A frequency-modulated, telemetric system with a transducer sensitive to variation in distance between two points was developed and used to measure in vivo small intestinal motor function in unanesthetized dogs. The construction of the system and one application of it to the study of gastrointestinal motility is described. Data were recorded after fasting, 1 h after feeding a standardized meat meal, and after intravenous injections of pentagastrin. A significant increase in motility was seen after pentagastrin injections and feeding as compared to the motility pattern seen in a fasting animal, and the telemetric system was proven adequate for in vivo measurement of motility of the gastrointestinal tract.

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