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Muscle Attachment (muscle + attachment)

Distribution by Scientific Domains

Medical Sciences	50%

Selected Abstracts

DEVELOPMENT AND DIVERSIFICATION OF TRUNK PLATES OF THE LOWER CAMBRIAN LOBOPODIANS

PALAEONTOLOGY, Issue 2 2007
XI-GUANG ZHANG
Abstract:, Isolated lobopodian plates are reported from Early Cambrian strata at five localities in southern China. A wide variety of morphologies is represented, reflecting a considerable diversification within the phylum at this time. The new taxon Microdictyon jinshaense is erected and new observations are recorded on established taxa, based on examination of more than 600 well-preserved plates; irregular patterns of node distribution and the presence of large spines are documented on some taxa for the first time. Rare specimens in which two plates are conjoined, with a larger plate underlying a smaller one, are interpreted as showing a new sclerite emerging underneath its predecessor, which has not yet been moulted. These specimens confirm the process of ecdysis in the lobopodians and contribute to a fuller understanding of the ontogeny of these organisms. A functional hypothesis that suggests that the plates were complex visual structures is refuted; it is possible that they were sites of muscle attachment, but a protective role is regarded as more plausible. [source]

A TERRESTRIAL STEREOSPONDYL FROM THE LOWER TRIASSIC OF SOUTH AFRICA: THE POSTCRANIAL SKELETON OF LYDEKKERINA HUXLEYI (AMPHIBIA: TEMNOSPONDYLI)

PALAEONTOLOGY, Issue 2 2005
K. PAWLEY
Abstract:, Description of the postcranial skeleton of the basal stereospondyl amphibian Lydekkerina huxleyi from new material shows it to be heavily ossified with large processes for muscle attachment and well-developed articulation surfaces. The structure of the postcranial skeleton implies a substantial capability for terrestrial locomotion, rather than a primarily aquatic existence as has been suggested for most other stereospondyls. The postcranial skeleton is most similar to that of Uranocentrodon and the Archegosauroidea, and is unlike that of the poorly ossified, more derived stereospondyls and Dvinosauria. The postcranial skeleton does not display any of the particular apomorphies of the fully ossified Permian terrestrial temnospondyls. Cladistic analysis using the postcranial data obtained in this study indicates that within the Stereospondyli Lydekkerina huxleyi is neither a member of the Rhinesuchidae nor the Mastodonsauroidea, rather the Lydekkerinidae are a separate taxon. [source]

Stem cell markers (cytokeratin 15, CD34 and nestin) in primary scarring and nonscarring alopecia

BRITISH JOURNAL OF DERMATOLOGY, Issue 3 2009
M.P. Hoang
Summary Background, Although the pathogenesis of most primary scarring alopecias is poorly understood, recent studies implicate the bulge region as a possible target. Objectives, To corroborate these results, we ascertained involvement of follicular bulge stem cells using a panel of antibodies that putatively targeted the same. Methods, Antibodies used included anticytokeratin (CK) 15, CD34 and nestin on vertical and horizontal tissue sections of 50 cases of scarring and 34 cases of nonscarring alopecia. Results, Comparing expression of these markers in scarring vs. nonscarring alopecia, CK15 was noted in the follicular bulge region in 23 of 43 (53%) vs. 27 of 27 (100%) cases and in the peripheral layer of the outer root sheath (ORS) (upper two-thirds of the follicle) in 50 of 50 (100%) vs. 34 of 34 (100%) cases; CD34 was noted in the peripheral layer of the ORS (below pilar muscle attachment) in 24 of 35 (69%) vs. 18 of 18 (100%) cases; and nestin was noted in the infundibular region in 18 of 46 (39%) vs. seven of 32 (22%) cases and in the inner aspect of the ORS (below pilar muscle attachment) in eight of 31 (26%) vs. 23 of 23 (100%) cases. Conclusions, Our findings of differential follicular localization of stem cells underscore follicular progenitor cell heterogeneity and suggest the target in scarring alopecia is not merely follicular bulge stem cells but involves stem cells in the inner and outer aspect of the ORS. Enhanced expression of nestin in the infundibular region in scarring alopecia indicates availability of an accessible, in vivo niche of potential utility as an autologous source of stem cells for therapeutic application. [source]

Octopus Papillary Muscle Associated with a Left Lateral Accessory Pathway

CONGENITAL HEART DISEASE, Issue 6 2009
Manisha S. Patel MD
ABSTRACT Left ventricular papillary muscle abnormalities are rare malformations. They have been related to significant mitral valve dysfunction and left ventricular midcavitary obstruction. We report our experience with a young adult who presented with palpitations. An echocardiogram on the patient showed an "octopus-like" left ventricular papillary muscle. Subsequent electrophysiologic testing showed evidence of supraventricular tachycardia via a left lateral accessory pathway associated with the abnormal insertion of the papillary muscle attachments. [source]