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Full-Text Articles in Cell Biology

The Central Role Of The Tail In Switching Off 10s Myosin Ii Activity, Shixin Yang, Kyounghwan Lee, John L. Woodhead, Osamu Sato, Mitsuo Ikebe, Roger Craig Sep 2019

The Central Role Of The Tail In Switching Off 10s Myosin Ii Activity, Shixin Yang, Kyounghwan Lee, John L. Woodhead, Osamu Sato, Mitsuo Ikebe, Roger Craig

Radiology Publications

Myosin II is a motor protein with two heads and an extended tail that plays an essential role in cell motility. Its active form is a polymer (myosin filament) that pulls on actin to generate motion. Its inactive form is a monomer with a compact structure (10S sedimentation coefficient), in which the tail is folded and the two heads interact with each other, inhibiting activity. This conformation is thought to function in cells as an energy-conserving form of the molecule suitable for storage as well as transport to sites of filament assembly. The mechanism of inhibition of the compact molecule ...


Characterization Of Calbindin Positive Interneurons Within The Ventral Horn Of The Mouse Spinal Cord, Taylor L. Floyd, David R. Ladle Jan 2015

Characterization Of Calbindin Positive Interneurons Within The Ventral Horn Of The Mouse Spinal Cord, Taylor L. Floyd, David R. Ladle

Symposium of Student Research, Scholarship, and Creative Activities Materials

Sensory-motor circuits in the spinal cord integrate sensory feedback from muscles and modulate locomotor behavior. Although we know how the sensory-motor system generally works, the main issue lies in identifying all neurons involved and understanding their interrelationships. Many interneurons contribute to sensory-motor circuits and have been well studied. For example, Renshaw cells (RC) are inhibitory interneurons that prevent motor neurons from over-activity. A distinguishing feature of RCs is that they are the only interneurons within the ventral-most region of the spinal cord expressing the calcium binding protein calbindin (CB). Recent studies have found other subpopulations of ventral horn interneurons outside ...


Human Anatomy And Physiology Preparatory Course, Carlos Liachovitzky Jan 2015

Human Anatomy And Physiology Preparatory Course, Carlos Liachovitzky

Open Educational Resources

The overall purpose of this preparatory course textbook is to help students familiarize with some terms and some basic concepts they will find later in the Human Anatomy and Physiology I course.

The organization and functioning of the human organism generally is discussed in terms of different levels of increasing complexity, from the smallest building blocks to the entire body. This Anatomy and Physiology preparatory course covers the foundations on the chemical level, and a basic introduction to cellular level, organ level, and organ system levels. There is also an introduction to homeostasis at the beginning.


Self-Consistent Analyses For Potential Conduction Block In Nerves By An Ultrashort High-Intensity Electric Pulse, R. P. Joshi, A. Mishra, Q. Hu, K. H. Schoenbach, A. Pakhomov Jan 2007

Self-Consistent Analyses For Potential Conduction Block In Nerves By An Ultrashort High-Intensity Electric Pulse, R. P. Joshi, A. Mishra, Q. Hu, K. H. Schoenbach, A. Pakhomov

Bioelectrics Publications

Simulation studies are presented that probe the possibility of using high-field (>100kV ∕ cm), short-duration (∼50ns) electrical pulses for nonthermal and reversible cessation of biological electrical signaling pathways. This would have obvious applications in neurophysiology, clinical research, neuromuscular stimulation therapies, and even nonlethal bioweapons development. The concept is based on the creation of a sufficiently high density of pores on the nerve membrane by an electric pulse. This modulates membrane conductance and presents an effective "electrical short" to an incident voltage wave traveling across a nerve. Net blocking of action potential propagation can then result. A continuum approach based on the ...


Improved Energy Model For Membrane Electroporation In Biological Cells Subjected To Electrical Pulses, R. P. Joshi, Q. Hu, K. H. Schoenbach, H. P. Hjalmarson Jan 2002

Improved Energy Model For Membrane Electroporation In Biological Cells Subjected To Electrical Pulses, R. P. Joshi, Q. Hu, K. H. Schoenbach, H. P. Hjalmarson

Bioelectrics Publications

A self-consistent model analysis of electroporation in biological cells has been carried out based on an improved energy model. The simple energy model used in the literature is somewhat incorrect and unphysical for a variety of reasons. Our model for the pore formation energy E(r) includes a dependence on pore population and density. It also allows for variable surface tension, incorporates the effects of finite conductivity on the electrostatic correction term, and is dynamic in nature. Self-consistent calculations, based on a coupled scheme involving the Smoluchowski equation and the improved energy model, are presented. It is shown that E ...


Effect Of The Presence Of The Mammary Gland On Periparturient Immunosuppression In Dairy Cows , Kayoko Kimura Jan 1999

Effect Of The Presence Of The Mammary Gland On Periparturient Immunosuppression In Dairy Cows , Kayoko Kimura

Retrospective Theses and Dissertations

Impaired neutrophil and lymphocyte function during the periparturient period is a contributing factor to the high incidence of infectious disease observed in the periparturient cow. Using 8 multiparous Jersey cows, we demonstrated that populations of T cells, especially T helper cells and gd T cells declined during the periparturient period coincident with reported losses of immune cell function;We hypothesized that milk production may be an important immunosuppressive factor. To test this hypothesis, we used 10 mastectomized and 8 intact multiparous Jersey cows and examined phenotype of peripheral blood mononuclear cells (PBMC), adhesion molecule expression and myeloperoxidase activity in neutrophils ...


Mechanisms Of Arginine Vasopressin-Induced Insulin Secretion In Rinm5f Cells , Ter-Hsin Chen Jan 1996

Mechanisms Of Arginine Vasopressin-Induced Insulin Secretion In Rinm5f Cells , Ter-Hsin Chen

Retrospective Theses and Dissertations

The present study was to investigate the mechanism by which AVP increases insulin secretion in RINm5F cells. A specific PLC inhibitor, U-73122, and a PLA2 inhibitor, N-(p-amylcinnamoyl)anthranilic acid (ACA) were used. U-73122 (2-8 [mu]M) inhibited the AVP-induced increases in the intracellular concentration of inositol 1,3,4-trisphosphate and (Ca2+]i dose-dependently. U-73122 (8 [mu]M) abolished the AVP's effect on IP3 and (Ca2+]i, but it only reduced the AVP-induced increase in insulin secretion by 35%. The discrepancy between the results of (Ca2+]i and insulin secretion may be due to the multiple signal transduction pathways ...


Biochemical Composition Of The Spermatozoal Plasma Membrane In Normal And Heat-Stressed Boars , Gary Carl Althouse Jan 1992

Biochemical Composition Of The Spermatozoal Plasma Membrane In Normal And Heat-Stressed Boars , Gary Carl Althouse

Retrospective Theses and Dissertations

The biochemical composition of ejaculated spermatozoal plasma membranes from normal-control (n = 4) and heat-stressed (n = 4) paired, sibling boars was assessed over a 9-week collection period. A total of 36 ejaculates were collected from the normal-control boars. Phospholipids (PL) accounted for 83.5% of the membrane lipid material, with sterols making up the remaining 16.5%. Phosphatidylcholine was the most abundant PL (56.6%), followed by sphingomyelin (16.6%), phosphatidylglycerides (11.0%), lysophosphatidylcholine (9.0%), phosphatidylethanolamine (5.8%), and phosphatidylinositol (1.0%). Cholesterol was the major sterol found in the sperm's plasma membrane (72.1%), with desmosterol being the ...