Hedgehog proteins mediate many of the inductive interactions that determine cell fate during embryonic development. Hedgehog signaling has been shown to regulate slow muscle fiber type development. We report here that mutations in the zebrafish slow-muscle-omitted (smu) gene disrupt many developmental processes involving Hedgehog signaling. smu(-/-) embryos have a 99% reduction in the number of...

A three-dimensional biomechanical model of tissue deformation was developed to simulate dynamic vocal fold abduction and adduction. The model was made of 1721 nearly incompressible finite elements. The cricoarytenoid joint was modeled as a rocking-sliding motion, similar to two concentric cylinders. The vocal ligament and the thyroarytenoid muscle's fiber characteristics were implemented as a f...

Purpose The goal of this study was to determine if continuous application of insulin-like growth factor-1 (IGF-1) could improve eye alignment of adult strabismic nonhuman primates and to assess possible mechanisms of effect. Methods A continuous release pellet of IGF-1 was placed on one medial rectus muscle in two adult nonhuman primates (M1, M2) rendered exotropic by the alternating monocula...

Loss of muscle force is a salient feature of Duchenne muscular dystrophy (DMD), a fatal disease caused by dystrophin deficiency. Assessment of force production from a single intact muscle has been considered as the gold standard for studying physiological consequences in murine models of DMD. Unfortunately, equivalent assays have not been established in dystrophic dogs. To fill the gap, we deve...

!is thesis concerns aspects of Forkhead gene biology and it’s relation to mammalian development. Genes from three subclasses are discussed, Foxj3, Foxf1 and f2, and Foxe3. We have identified and characterized a novel forkhead gene, FoxJ3, that is expressed in neuroectoderm, neural crest and mytome, suggesting possible function in the nervous system and muscle. !e myotome, which will develop int...

TASAKI, I. AND S. HAGIWARA. (Natl. Insts. Health, Bethesda, Md., and U. California, Los Angeles.) Capacity of muscle jiber membrane. Am. J. Physiol. 188(3): 423-429. 1957 .-Using two or three microelectrodes inserted into single muscle fibers of the toad sartorius, the electric impedance of the muscle fiber membrane was measured with a.c. between 25 and 1500 cps. It was found that the capacity ...

The sternocleidomastoid muscle is located in the neck and is both a neck rotator and flexor. Cervical dystonia, a focal dystonia disorder, is characterized by forceful involuntary contraction of a group of neck muscles, usually including the sternocleidomastoid. Little is known about the fiber type composition, fiber type compartmentalization and innervation patterns in this muscle in rabbit an...

Rats were trained for 5 days by running on either an inclined or declined treadmill. Three days later, the rats were anesthetized, and angle-torque curves were plotted for the vastus intermedius muscles. The maximum active torque was generated at significantly greater muscle lengths for muscles from decline-trained rats compared with incline-trained rats. Sixteen muscles were then fixed and aci...

A new musculoskeltal simulation primitive, the strand, can provide an efficient way of simulating complicated muscle fiber architectures [1]. In this paper we present a new fiber tracking algorithm based on an energy minimizing active curve that is well suited for building these strand type models from diffusion tensor imaging data. We present fiber tracking results for the Brachioradialis musc...