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Achilleo-calcaneal-plantar complex: reality or virtuality?
No full textdue to insufficient description of its myology, particularly the deep muscles. In the present study a detailed description of the deep muscles of the lower leg is given, based on micro-dissection and, in situ, by imaging techniques. Membrana interossea cruris covers the anterior surface of musculus interosseus cruris, extended between tibia and fibula. Distally it proceeds as a relatively strong interosseous ligament. Musculus interosseus cruris consists of several bundles, interconnecting tibia and fibula. Musculus pronator profundus is located posterior to m. interosseus cruris. Its superior fibres are directed from caput fibulae to corpus tibiae, resembling the condition of m. popliteus in higher mammals. Direction of the inferior bundles of m. pronator profundus coincides approximately with the direction of the crus. They are inserted in a vertical tendon at the level of the tibial and fibular epiphyses. This tendon is continuous with the meniscoid crossing ligaments of the fibulotalar joint. Distally, transverse muscle bundles overly this tendon superficially. It is likely that all of these deep muscles are involved in rotation mechanisms during locomotion. Their positions within the flexor compartment of the lower leg suggest pronator functions in particular. Coapting effects on tibia and fibula may be expected. P5 Descending afferent projections to the m-region in the cat The M(= medial)-region, also called pontine mic-turition center or Barrington's nucleus in the dorsolateral pontine tegmentum controls micturi-tion. Its axons terminate in the sacral intermediolateral cell group (IML) and the dorsal intermediomedial cell group (IMM) of the sacral spinal cord. The IML contains preganglionic para-sympathetic motoneurons that innervate the bladder, and the IMM contains GABA-and glycinergic neurons that inhibit urethral sphincter motoneurons. Stimulation in the M-region results in micturition. In order to find out which brain regions have direct control of micturition, the present study attempted to determine which regions in mes-, di-and telencephalon send fibers to the M-region. In five female cats WGA-HRP injections were made in the area of the dorsolateral pontine tegmentum including the M-region. The sacral spinal cord and brain were cut into serial transverse sections. In all cases anterogradely labeled fibers were found in the IML and IMM. Retrogradely labeled neurons were found in the dorsal, lateral and ventrolateral periaqueductal gray (PAG), ventromedial hypothalamus, medial preoptic area (MPO), bed nucleus of the stria terminalis, central nucleus of the amygdala, infra-limbic cortex and prelimbic cortex. To verify whether these areas indeed project to the M-region or to adjacent structures, [ 3 H]leucine and WGA-HRP injections were made in those regions in which retrogradely labeled neurons were found. Results show that only the ventrolateral and dorsal PAG and the MPO project to the M-region and have direct control of micturition. All other parts of the limbic system that have been shown to influence micturition must have indirect projections to the M-region via PAG or MPO. P6 Achilleo-calcaneal-plantar complex: reality or virtuality
Achilleo-calcaneal-plantar complex: reality or virtuality?
No full textdue to insufficient description of its myology, particularly the deep muscles. In the present study a detailed description of the deep muscles of the lower leg is given, based on micro-dissection and, in situ, by imaging techniques. Membrana interossea cruris covers the anterior surface of musculus interosseus cruris, extended between tibia and fibula. Distally it proceeds as a relatively strong interosseous ligament. Musculus interosseus cruris consists of several bundles, interconnecting tibia and fibula. Musculus pronator profundus is located posterior to m. interosseus cruris. Its superior fibres are directed from caput fibulae to corpus tibiae, resembling the condition of m. popliteus in higher mammals. Direction of the inferior bundles of m. pronator profundus coincides approximately with the direction of the crus. They are inserted in a vertical tendon at the level of the tibial and fibular epiphyses. This tendon is continuous with the meniscoid crossing ligaments of the fibulotalar joint. Distally, transverse muscle bundles overly this tendon superficially. It is likely that all of these deep muscles are involved in rotation mechanisms during locomotion. Their positions within the flexor compartment of the lower leg suggest pronator functions in particular. Coapting effects on tibia and fibula may be expected. P5 Descending afferent projections to the m-region in the cat The M(= medial)-region, also called pontine mic-turition center or Barrington's nucleus in the dorsolateral pontine tegmentum controls micturi-tion. Its axons terminate in the sacral intermediolateral cell group (IML) and the dorsal intermediomedial cell group (IMM) of the sacral spinal cord. The IML contains preganglionic para-sympathetic motoneurons that innervate the bladder, and the IMM contains GABA-and glycinergic neurons that inhibit urethral sphincter motoneurons. Stimulation in the M-region results in micturition. In order to find out which brain regions have direct control of micturition, the present study attempted to determine which regions in mes-, di-and telencephalon send fibers to the M-region. In five female cats WGA-HRP injections were made in the area of the dorsolateral pontine tegmentum including the M-region. The sacral spinal cord and brain were cut into serial transverse sections. In all cases anterogradely labeled fibers were found in the IML and IMM. Retrogradely labeled neurons were found in the dorsal, lateral and ventrolateral periaqueductal gray (PAG), ventromedial hypothalamus, medial preoptic area (MPO), bed nucleus of the stria terminalis, central nucleus of the amygdala, infra-limbic cortex and prelimbic cortex. To verify whether these areas indeed project to the M-region or to adjacent structures, [ 3 H]leucine and WGA-HRP injections were made in those regions in which retrogradely labeled neurons were found. Results show that only the ventrolateral and dorsal PAG and the MPO project to the M-region and have direct control of micturition. All other parts of the limbic system that have been shown to influence micturition must have indirect projections to the M-region via PAG or MPO. P6 Achilleo-calcaneal-plantar complex: reality or virtuality
The influence of finger position on percussion sounds
No full textPercussion sounds of the chest are resonant sounds induced by striking one finger upon another finger applied firmly to the chest. They have the greatest content of energy in the range of 150 - 200 Hz. The character of the percussion sounds may change due to pathological processes (Sovijärvi et al., 2000). The striking finger must be flexed in both interphalangeal joints simultaneously, to acquire a stable arched finger position. This condition is due to local shifts within the so-called extensor assembly of the finger, which is the anatomical structure where tendons of extrinsic and intrinsic finger muscles converge (Van Zwieten et al., 2002). The stability of the arch of the striking finger contributes to its rigidity, thus influencing the quality of percussion sounds produced
Dynamical model of the human arm taking into account the form of the contact sufaces of the joints
No full text
The influence of finger position on percussion sounds
No full textPercussion sounds of the chest are resonant sounds induced by striking one finger upon another finger applied firmly to the chest. They have the greatest content of energy in the range of 150 - 200 Hz. The character of the percussion sounds may change due to pathological processes (Sovijärvi et al., 2000). The striking finger must be flexed in both interphalangeal joints simultaneously, to acquire a stable arched finger position. This condition is due to local shifts within the so-called extensor assembly of the finger, which is the anatomical structure where tendons of extrinsic and intrinsic finger muscles converge (Van Zwieten et al., 2002). The stability of the arch of the striking finger contributes to its rigidity, thus influencing the quality of percussion sounds produced
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Deep muscles in the lower leg of the opossum
No full textthe dopaminergic character of any of these progenitor cells. Double immunostaining for TH and the markers for young cells may reveal the possible dopaminergic character of the progenitors. P2 Segmental and quantitative differences between lamina I-thalamic and lamina I-periaqueductal grey projecting neurons in the cat Lamina I projections to either thalamus or periaque-ductal grey (PAG) have been described in different species, but the differences in number and distribution of these lamina I cells in each segment of the spinal cord (C1-Coc2) have not been studied before. In the cat, large WGA-HRP injections were made in the thalamus, and the results were compared with those from earlier studies of this laboratory on the spinal projections to the PAG (Mouton & Holstege, 1998, 2000), using the same materials and methods. Throughout the length of the spinal cord, at least twice as many lamina I cells were labeled after PAG injections as after thalamus injections. This difference was strongest for the lower lumbar and sacral cord, where many more labeled lamina I-PAG than lamina I-thalamic cells were found. In the thalamus injected cases most labeled lamina I neurons were found in the C7 segment, while in the PAG injected cases they were most numerous in C5-C6 and the upper thoracic segments. The present findings suggest that the lamina I-PAG pathway plays a more important role in nociception than the lamina I-thalamic pathway. The great difference between the number of lamina I cells projecting to the thalamus and PAG in the lumbosacral region may reflect the relay of specific non-nociceptive urogenital information to the PAG. P3 Developmental changes in endocardial expression of shear stress responsive genes KLF-2, ET-1 and NOS-3 in chicken embryos Hemodynamics play an important role in normal cardiogenesis and changes in blood flow can cause congenital heart malformations (Hogers et al., 1999). Since shear stress is positively correlated to flow it is also important in cardiac development. Endothelin-1 (ET-1) is a growth hormone and vasoconstrictor. The gene contains a shear stress response element (SSRE) in its promoter region, like the gene for endothelial nitric oxide synthase (NOS-3). NOS-3 produces NO, which is the functional counterpart of ET-1, a vasodilator. Expression of Lung Krü ppel-like factor (KLF-2) has been related to shear stress as it is expressed in the endothelium of the adult human aorta at sites of high shear stress. From in vitro experiments it is known that KLF-2 and NOS-3 are upregulated by high shear stress, whereas ET-1 is downregulated. In this study the expression patterns of these shear responsive genes KLF-2, ET-1 and NOS-3 were investigated during chicken cardiovascular development from stage HH16 to HH30. According to the in vitro studies ET-1 was expected to be low or absent and NOS-3 to be high at sites where KLF-2 expression is high. Using radioactive in situ hybridisation, it was shown that in the early stages expression patterns are mostly not shear-related, whereas during development this correlation becomes stronger. Patterns of KLF-2 and NOS-3 overlap in the endocardium at lumen constrictions in the heart, such as the sino-atrial transition, the atrioventricular canal and the outflow tract. In these regions KLF-2 and NOS-3 mRNA exclude that of ET-1. In the early stages the aortic sac and the pharyngeal arch arteries show KLF-2 and NOS-3 expression, where ET-1 is negative. Our results suggest that in the embryonic cardiovas-cular system KLF-2 is expressed in regions of highest shear stress, and that ET-1 and NOS-3 are, at least in the later stages, related to shear stress. REFERENCE Hogers B, DeRuiter MC, Gittenberger-de Groot AC, Poelmann RE. 1999. Extraembryonic venous obstructions lead to cardiovascular malformations and can be embryolethal. Cardiovasc Res 41:87-99. P4 Deep muscles in the lower leg of the opossu
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