Early steps of paired fin development in zebrafish compared with tetrapod limb development.

The development of zebrafish paired fins and tetrapod forelimbs and hindlimbs show striking similarities at the molecular level. In recent years, the zebrafish, Danio rerio has become a valuable model for the study of the development of vertebrate paired appendages and several large-scale mutagenesis screens have identified novel fin mutants. This review summarizes recent advances in research into zebrafish paired fin development and highlights features that are shared with and distinct from limb development in other main animal models.

Proximodistal identity during vertebrate limb regeneration is regulated by Meis homeodomain proteins

The mechanisms by which cells obtain instructions to precisely re-create the missing parts of an organ remain an unresolved question in regenerative biology. Urodele limb regeneration is a powerful model in which to study these mechanisms. Following limb amputation, blastema cells interpret the proximal-most positional identity in the stump to reproduce missing parts faithfully. Classical experiments showed the ability of retinoic acid (RA) to proximalize blastema positional values. Meis homeobox genes are involved in RA-dependent specification of proximal cell identity during limb development. To understand the molecular basis for specifying proximal positional identities during regeneration, we isolated the axolotl Meis homeobox family. Axolotl Meis genes are RA-regulated during both regeneration and embryonic limb development. During limb regeneration, Meis overexpression relocates distal blastema cells to more proximal locations, whereas Meis knockdown inhibits RA proximalization of limb blastemas. Meis genes are thus crucial targets of RA proximalizing activity on blastema cells.

Opposing RA and FGF signals control proximodistal vertebrate limb development through regulation of Meis genes.

Vertebrate limbs develop in a temporal proximodistal sequence, with proximal regions specified and generated earlier than distal ones. Whereas considerable information is available on the mechanisms promoting limb growth, those involved in determining the proximodistal identity of limb parts remain largely unknown. We show here that retinoic acid (RA) is an upstream activator of the proximal determinant genes Meis1 and Meis2. RA promotes proximalization of limb cells and endogenous RA signaling is required to maintain the proximal Meis domain in the limb. RA synthesis and signaling range, which initially span the entire lateral plate mesoderm, become restricted to proximal limb domains by the apical ectodermal ridge (AER) activity following limb initiation. We identify fibroblast growth factor (FGF) as the main molecule responsible for this AER activity and propose a model integrating the role of FGF in limb cell proliferation, with a specific function in promoting distalization through inhibition of RA production and signaling.

Guidelines for enhancement of visual conspicuity of the trailing end of trains. Final report.

Federal Railroad Administration, Office of Research, Development and Demonstrations, Washington, D.C.

A limb o' the law : a comedy in two acts /

Mode of access: Internet.

Glossariu care coprinde vorbele d'in limb'a romana straine prin originea sau form'a loru, cumu si celle de origine indouiosa. Dupo insarcinarea data de Societatea academica romana,

Cover dated 1876.

The insidious Dr. Fu-Manchu, being a somewhat detailed account of the amazing adventures of Nayland Smith in his trailing of the sinister Chinaman,

"Second printing, September, 1913.

Transverse-Plane Ankle Rotation for Lower-Limb Amputees Using Two Novel Prostheses

Thesis (Ph.D.)--University of Washington, 2016-06

Patients with chronic neck pain demonstrate altered patterns of muscle activation during performance of a functional upper limb task

Study Design. Cross-sectional study. Objective. This study compared neck muscle activation patterns during and after a repetitive upper limb task between patients with idiopathic neck pain, whiplash-associated disorders, and controls. Summary of Background Data. Previous studies have identified altered motor control of the upper trapezius during functional tasks in patients with neck pain. Whether the cervical flexor muscles demonstrate altered motor control during functional activities is unknown. Methods. Electromyographic activity was recorded from the sternocleidomastoid, anterior scalenes, and upper trapezius muscles. Root mean square electromyographic amplitude was calculated during and on completion of a functional task. Results. A general trend was evident to suggest greatest electromyograph amplitude in the sternocleidomastoid, anterior scalenes, and left upper trapezius muscles for the whiplash-associated disorders group, followed by the idiopathic group, with lowest electromyographic amplitude recorded for the control group. A reverse effect was apparent for the right upper trapezius muscle. The level of perceived disability ( Neck Disability Index score) had a significant effect on the electromyographic amplitude recorded between neck pain patients. Conclusions. Patients with neck pain demonstrated greater activation of accessory neck muscles during a repetitive upper limb task compared to asymptomatic controls. Greater activation of the cervical muscles in patients with neck pain may represent an altered pattern of motor control to compensate for reduced activation of painful muscles. Greater perceived disability among patients with neck pain accounted for the greater electromyographic amplitude of the superficial cervical muscles during performance of the functional task.

Foot orthotics in the treatment of lower limb conditions: A musculoskeletal physiotherapy perspective

Orthotic therapy is frequently advocated for the treatment Of musculoskeletal pain and injury of the lower limb. The clinical efficacy, mechanical effects, and Underlying mechanism of the action of foot orthotics has not been Conclusively determined making it difficult for practitioners to agree on a reliable and valid clinical approach to their application and indeed even their fabrication. This problem is compounded by evidence suggesting that the most commonly used approach for orthotic prescription, the (Biomechanical Evaluation of the Foot. Vol. 1. Clinical Biomechanics Corporation, Los Angeles, 1971) approach, has poor validity and many of the associated clinical measurements of that approach lack adequate levels of reliability. This paper proposes a new approach that is based on two key elements. One is the identification, verification and quantification of physical tasks that serve as client specific outcome measures. The second is the application of specific physical manipulations during the performance of these physical tasks. The physical manipulations are selected on the basis of motion dysfunction and their immediate effects on the client specific outcome measures serve as the basis to making an informed decision on the propriety of using orthotics in individual clients. The motion dysfunction also guides the type of orthotic that is applied. Practical case examples as well Lis generic and specific guidelines to the application of this clinical assessment process and orthotics are provided in this paper. (C) 2004 Published by Elsevier Ltd.

Dysynchiria: Watching the mirror image of the unaffected limb elicits pain on the affected side

People with complex regional pain syndrome type 1 (CRPS1) watched a reflected image of their unaffected limb being touched and felt pain or paresthesia at the corresponding site on the affected limb. The authors suggest that allodynia and paresthesia can be mediated by the brain and that dysynchiria has implications for the understanding and management of CRPS1.

Muscle fiber conduction velocity of the upper trapezius muscle during dynamic contraction of the upper limb in patients with chronic neck pain

The purpose of this study was to compare average muscle fiber conduction velocity (CV) and its changes over time in the upper trapezius muscle during a repetitive upper limb task in people with chronic neck pain and in healthy controls. Surface EMG signals were detected bilaterally from the upper trapezius muscle of 19 patients and nine healthy controls using linear adhesive arrays of four electrodes. Subjects were asked to tap their hands in a cyclic manner between targets positioned mid-thigh and 120 degrees of shoulder flexion, to the beat of a metronome set at 88 beats/min for up to 5 min. Muscle fiber CV and instantaneous mean power spectral frequency were estimated for each cycle at the time instant corresponding to 90 degrees of shoulder flexion. Average muscle fiber CV of the upper trapezius muscle was higher in people with chronic neck pain (mean +/- SE, 4.8 +/- 0.1 m/s) than in control subjects (4.4 +/- 0.1 m/s; P