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ELife May 2022The dorsal axial muscles, or epaxial muscles, are a fundamental structure covering the spinal cord and vertebrae, as well as mobilizing the vertebrate trunk. To date,...
The dorsal axial muscles, or epaxial muscles, are a fundamental structure covering the spinal cord and vertebrae, as well as mobilizing the vertebrate trunk. To date, mechanisms underlying the morphogenetic process shaping the epaxial myotome are largely unknown. To address this, we used the medaka -enhancer mutant (), which exhibits ventralized dorsal trunk structures resulting in impaired epaxial myotome morphology and incomplete coverage over the neural tube. In wild type, dorsal dermomyotome (DM) cells reduce their proliferative activity after somitogenesis. Subsequently, a subset of DM cells, which does not differentiate into the myotome population, begins to form unique large protrusions extending dorsally to guide the epaxial myotome dorsally. In , by contrast, DM cells maintain the high proliferative activity and mainly form small protrusions. By combining RNA- and ChIP-sequencing analyses, we revealed direct targets of Zic1, which are specifically expressed in dorsal somites and involved in various aspects of development, such as cell migration, extracellular matrix organization, and cell-cell communication. Among these, we identified as a crucial factor regulating both cell proliferation and protrusive activity of DM cells. We propose that dorsal extension of the epaxial myotome is guided by a non-myogenic subpopulation of DM cells and that empowers the DM cells to drive the coverage of the neural tube by the epaxial myotome.
Topics: Animals; Embryonic Development; Gene Expression Regulation, Developmental; Morphogenesis; Oryzias; Somites; Wnt Proteins
PubMed: 35522214
DOI: 10.7554/eLife.71845 -
Bordeaux Chirurgical 1951
Topics: Discitis; Humans; Intervertebral Disc
PubMed: 14839184
DOI: No ID Found -
Der Unfallchirurg Sep 1990This collective study was conducted by the German section of AO International to work out the indications for fixation of the tibial shaft by means of dorsal plating....
This collective study was conducted by the German section of AO International to work out the indications for fixation of the tibial shaft by means of dorsal plating. Primary dorsal plating was done in 70 cases. Most of the patients had second- or third-degree open fractures with severe ventral soft tissue injuries or closed fractures that could not be reduced and fixed conservatively. In 72 patients, secondary dorsal plate fixation was performed. The main reason for the dorsally positioned plate was persistent instability or axial malalignment after previous external or internal fixation, but failed conservative treatment constituted a further reason. Most of these patients had such severe damage following fractures that dorsal plating was the last chance of avoiding amputation. The high rate of complications (12 infections and 7 non-unions and breakages of implants after primary dorsal plating; 20 infections and 11 non-unions and breakages of implants after secondary dorsal plating) has to be considered in the light of the extraordinary indications for the dorsal plating of the tibial shaft in especially severe fractures or disastrous sequelae. In cases with extremely severe conditions before fixation, dorsal plating of the tibial shaft for secondary operative treatment yields adequate results.
Topics: Adult; Amputation, Surgical; Bone Plates; Cohort Studies; External Fixators; Female; Fractures, Open; Humans; Male; Middle Aged; Osteomyelitis; Radiography; Tibial Fractures
PubMed: 2218555
DOI: No ID Found -
Veterinary Surgery : VS Apr 2009To (1) report a technique for repair of feline ilial fractures using a dorsally applied bone plate and (2) compare outcome with cats treated by a lateral plate. (Comparative Study)
Comparative Study
OBJECTIVE
To (1) report a technique for repair of feline ilial fractures using a dorsally applied bone plate and (2) compare outcome with cats treated by a lateral plate.
STUDY DESIGN
Prospective study.
ANIMALS
Cats (n=10) with iliac fractures.
METHODS
Cats with ilial fractures (January 2005-December 2006) were treated by application of a dorsally applied bone plate. Immediate postoperative radiographs were compared with those taken 4-6 weeks later to assess screw loosening, screw purchase, and pelvic canal narrowing. Owners were contacted for medium-term (>3 month) follow-up. Data were compared with a report of outcome after lateral plating (LP) in 21 cats.
RESULTS
Mean (+/- SD) screw purchase (89 +/- 11 mm) was significantly greater (P<.01) with a dorsal plate compared with a lateral plate (33 +/- 8 mm). Significantly more screws (P<.01) were used with a dorsal plate (median, 7) compared with a lateral plate (median, 6). Significantly less postoperative pelvic canal narrowing developed in the dorsal plating group between postoperative and 4-6-week follow-up radiography compared with the LP group (2% versus 15%, P<.01).
CONCLUSION
Dorsal plating of feline ilial fractures results in significantly less screw loosening and pelvic canal narrowing at 4-6 weeks after surgery compared with LP.
CLINICAL RELEVANCE
Dorsal plating of feline iliac fractures may reduce complications associated with pelvic canal narrowing such as constipation and megacolon.
Topics: Animals; Bone Plates; Bone Screws; Cats; Female; Fracture Fixation, Internal; Hip Fractures; Ilium; Lameness, Animal; Male; Prospective Studies; Radiography; Surveys and Questionnaires; Treatment Outcome
PubMed: 19573096
DOI: 10.1111/j.1532-950X.2009.00501.x -
The European Journal of Neuroscience Dec 2003The evolutionary relationship between telencephalic regions of the avian and mammalian brains has been a long-standing issue in comparative neuroanatomy. Based on...
The evolutionary relationship between telencephalic regions of the avian and mammalian brains has been a long-standing issue in comparative neuroanatomy. Based on various criteria, a number of homologous regions have been proposed. Recent studies in mammals have shown that basal regions of the telencephalon give rise to neurons that migrate dorsally and populate the cerebral cortex. In the present study we demonstrate that, similar to mammals, neurons from a ventricular region of the palaeo-striatal complex - the dorsal subpallial sulcus - of the chick telencephalon migrate dorsally to populate the developing pallium. Further characterization of these cells revealed that they express the neurotransmitter gamma-aminobutyric acid, but not the calcium-binding protein calbindin. These findings provide evidence that the mouse and chick basal regions are not only homologous in terms of gene expression patterns and connectivity, but they both also contribute inhibitory interneurons to dorsal regions of the developing telencephalon.
Topics: Animals; Calbindins; Cell Differentiation; Cell Movement; Chick Embryo; Chickens; Gene Expression Regulation, Developmental; Immunohistochemistry; Interneurons; Neural Inhibition; Neurons; Organ Culture Techniques; S100 Calcium Binding Protein G; Telencephalon; gamma-Aminobutyric Acid
PubMed: 14686912
DOI: 10.1111/j.1460-9568.2003.03059.x -
Development (Cambridge, England) Jun 1993The precursors for oligodendrocytes, the myelinating cells of the vertebrate CNS, appear to be initially restricted to ventral regions of the embryonic rat spinal cord....
The precursors for oligodendrocytes, the myelinating cells of the vertebrate CNS, appear to be initially restricted to ventral regions of the embryonic rat spinal cord. These cells subsequently populate dorsal spinal cord regions where they acquire the mature characteristics of oligodendrocytes. To determine the location and timing of proliferation of oligodendrocyte precursors in the ventral spinal cord, and to map their pathways of migration in vivo, an assay that identifies mitotic cells was used in conjunction with antibodies that distinguish astrocytes, oligodendrocytes and their precursors. Between E16.5 and E18.5, two hours after a maternal injection of BrdU, the majority of proliferating cells were located in a discrete cluster at the ventral ventricular zone dorsal to the ventral midline region of the developing spinal cord. By contrast, 12-24 hours following a BrdU injection at E16.5, increasing numbers of labeled cells were seen in the dorsal and more lateral locations of the spinal cord. These observations suggest that BrdU-labeled ventral ventricular cells, or their progeny migrate dorsally and laterally during subsequent spinal cord development. To determine the nature of these proliferating cells, cultures of dorsal and ventral spinal cord from BrdU-labeled animals were double-labeled with antibodies that identify oligodendrocytes or astrocytes and anti-BrdU. In dorsal spinal cord cultures derived from animals that had received a single injection of BrdU at E16.5, the majority of proliferating cells differentiated into astrocytes while, in ventrally derived cultures from the same animals, the majority of proliferating cells differentiated into oligodendrocytes. In dorsal cultures prepared from animals that received multiple injections of BrdU between E16.5 and E18.5, many more cells were labeled with BrdU and approximately half of these differentiated into oligodendrocytes. These observations suggest that during embryonic development proliferating oligodendrocyte precursors are initially located at the ventral ventricular zone dorsal to the ventral midline region of the spinal cord and during subsequent maturation these cells or their progeny migrated dorsally in the ventricular region of the spinal cord, and laterally to reside in the developing white matter.
Topics: Animals; Astrocytes; Bromodeoxyuridine; Cell Differentiation; Cell Division; Cells, Cultured; Immunohistochemistry; Neuroglia; Oligodendroglia; Rats; Spinal Cord; Stem Cells
PubMed: 8223279
DOI: 10.1242/dev.118.2.563 -
The Journal of Neuroscience : the... Aug 2003Using functional magnetic resonance imaging (fMRI), we mapped the retinotopic organization throughout the visual cortex of fixating monkeys. The retinotopy observed in...
Using functional magnetic resonance imaging (fMRI), we mapped the retinotopic organization throughout the visual cortex of fixating monkeys. The retinotopy observed in areas V1, V2, and V3 was completely consistent with the classical view. V1 and V3 were bordered rostrally by a vertical meridian representation, and V2 was bordered by a horizontal meridian. More anterior in occipital cortex, both areas V3A and MT-V5 had lower and upper visual field representations split by a horizontal meridian. The rostral border of dorsal V4 was characterized by the gradual transition of a representation of the vertical meridian (dorsally) to a representation of the horizontal meridian (more ventrally). Central and ventral V4, on the other hand, were rostrally bordered by a representation of the horizontal meridian. The eccentricity lines ran perpendicular to the ventral V3-V4 border but were parallel to the dorsal V3-V4 border. These results indicate different retinotopic organizations within dorsal and ventral V4, suggesting that the latter regions may not be merely the lower and upper visual field representations of a single area. Moreover, because the present fMRI data are in agreement with previously published electrophysiological results, reported distinctions in the retinotopic organization of human and monkey dorsal V4 reflect genuine species differences that cannot be attributed to technical confounds. Finally, aside from dorsal V4, the retinotopic organization of macaque early visual cortex (V1, V2, V3, V3A, and ventral V4) is remarkably similar to that observed in human fMRI studies. This finding indicates that early visual cortex is mostly conserved throughout hominid evolution.
Topics: Anesthesia; Animals; Brain Mapping; Consciousness; Macaca mulatta; Magnetic Resonance Imaging; Male; Visual Cortex; Visual Fields; Visual Pathways
PubMed: 12917375
DOI: 10.1523/JNEUROSCI.23-19-07395.2003 -
Annales de Chirurgie Plastique Et... Oct 2014The latissimus dorsi muscle flap is a type V according to Mathes and Nahai. It is vascularized by a proximal main pedicle represented by the thoraco-dorsal pedicle and...
INTRODUCTION
The latissimus dorsi muscle flap is a type V according to Mathes and Nahai. It is vascularized by a proximal main pedicle represented by the thoraco-dorsal pedicle and pedicle distal accessory represented by the dorsal branches of the posterior intercostal arteries. The main thoraco-dorsal pedicle has a descending branch and a transverse branch. This anatomical study clarifies the muscular territory vascularized by the transverse branch of thoraco-dorsal artery for a secondary use after harvesting a thoraco-dorsal artery perforator flap or a muscle-sparing latissimus dorsi flap.
MATERIAL AND METHODS
Our study focused on ten dissections latissimus dorsi muscle taken from five fresh cadavers chest, carried out within the University Department of Anatomy. The descending branch of thoraco-dorsal artery was ligated, the transverse branch was cannulated and injected with a mixture of barium sulfate/gelatin. After freezing, a static angiotomodensitometry (3D) of each flap was performed.
RESULTS
The average muscular surface vascularized by the transverse branch is measured at 80% (77% minimum value, maximum value 83%) of the complete latissimus dorsi muscle. Intermuscular connections between the two branches of thoraco-dorsal pedicle were shown.
CONCLUSION
The use of a ipsilateral latissimus dorsi muscle is a therapeutic option after harvesting a thoraco-dorsal artery perforator flap (TAP) or a muscle-sparing latissimus dorsi flap (MSLD-flap).
Topics: Arteries; Cadaver; Humans; Perforator Flap; Superficial Back Muscles
PubMed: 24986163
DOI: 10.1016/j.anplas.2014.05.005 -
Plastic and Reconstructive Surgery Mar 1978An unusual case of a dorsally placed supernumerary breast is presented, along with a short review of the literature.
An unusual case of a dorsally placed supernumerary breast is presented, along with a short review of the literature.
Topics: Adolescent; Back; Breast; Choristoma; Female; Humans; Male; Mastectomy; Mastitis; Pregnancy; Skin Neoplasms
PubMed: 564527
DOI: 10.1097/00006534-197803000-00025 -
Presse Medicale (Paris, France : 1983) Feb 2018
Topics: Epidural Neoplasms; Humans; Male; Middle Aged; Multiple Myeloma; Thoracic Vertebrae
PubMed: 29373280
DOI: 10.1016/j.lpm.2017.11.009