Dermomyotomal origin of the ribs as revealed by extirpation and transplantation experiments in chick and quail embryos

Development ◽  
1998 ◽  
Vol 125 (17) ◽  
pp. 3437-3443 ◽  
Author(s):  
N. Kato ◽  
H. Aoyama
Keyword(s):  
Distal Part ◽  
Proximal Part ◽  
Axial Skeleton ◽  
Middle Part ◽  
Medial Part ◽  
Lateral Plate ◽  
Intercostal Muscles ◽  
Transplantation Experiments ◽  
Chick And Quail Embryos

To elucidate role of the dermomyotome in the formation of the axial skeleton, we performed extirpation and transplantation experiments on the dermomyotomes in chick and quail embryos. When the thoracic dermomyotomes of chick embryos were removed, the intercostal muscles and the distal ribs were deficient, while the proximal ribs were more or less normal. Quail tissues including the dermomyotome, the ectoderm and the medial edge of lateral plate, were transplanted to replace chick dermomyotomes. In these chimeras, the ribs, which would be deficient without the back-transplantation, were recovered. The cells of the recovered part of the ribs as well as the intercostal muscles were derived from the quail transplants. These findings suggest that the distal rib originated from the dermomyotomes and not the sclerotome as previously believed. To localize the origin of the distal rib further, we removed restricted regions of the dermomyotomes along the mediolateral and the rostrocaudal axis. The more lateral the part of the dermomyotomes that we removed, the more distal the part of the ribs affected. On the contrary, when the rostral and caudal edges of the dermomyotomes were removed, only the vertebral ribs showed extensive deficiencies while removal of the middle part between the edges caused less deficiency. The sternal ribs were not deficient in either case, but were extensively affected when the entire lateral edge of dermomyotomes was included in the region removed. We conclude that the lateral edges of the dermomyotomes are the primordia of the sternal ribs, and the rostral and/or caudal edges of the medial part of dermomyotomes are the primordia of the distal part and not of the proximal part of the vertebral ribs.

Hindlimb patterning and mandible development require the Ptx1 gene

Development ◽  
1999 ◽  
Vol 126 (9) ◽  
pp. 1805-1810 ◽  
Author(s):  
C. Lanctot ◽  
A. Moreau ◽  
M. Chamberland ◽  
M.L. Tremblay ◽  
J. Drouin
Keyword(s):  
Gene Knockout ◽  
Proximal Part ◽  
Branchial Arch ◽  
Dorsal Side ◽  
Lateral Plate Mesoderm ◽  
Lateral Plate ◽  
Similar Time ◽  
The Right ◽  
Tetrapod Evolution

The restricted expression of the Ptx1 (Pitx1) gene in the posterior half of the lateral plate mesoderm has suggested that it may play a role in specification of posterior structures, in particular, specification of hindlimb identity. Ptx1 is also expressed in the most anterior ectoderm, the stomodeum, and in the first branchial arch. Ptx1 expression overlaps with that of Ptx2 in stomodeum and in posterior left lateral plate mesoderm. We now show that targeted inactivation of the mouse Ptx1 gene severely impairs hindlimb development: the ilium and knee cartilage are absent and the long bones are underdeveloped. Greater reduction of the right femur size in Ptx1 null mice suggests partial compensation by Ptx2 on the left side. The similarly sized tibia and fibula of mutant hindlimbs may be taken to resemble forelimb bones: however, the mutant limb buds appear to have retained their molecular identity as assessed by forelimb expression of Tbx5 and by hindlimb expression of Tbx4, even though Tbx4 expression is decreased in Ptx1 null mice. The hindlimb defects appear to be, at least partly, due to abnormal chondrogenesis. Since the most affected structures derive from the dorsal side of hindlimb buds, the data suggest that Ptx1 is responsible for patterning of these dorsal structures and that as such it may control development of hindlimb-specific features. Ptx1 inactivation also leads to loss of bones derived from the proximal part of the mandibular mesenchyme. The dual role of Ptx1 revealed by the gene knockout may reflect features of the mammalian jaw and hindlimbs that were acquired at a similar time during tetrapod evolution.

The role of Pax-1 in axial skeleton development

Development ◽  
1994 ◽  
Vol 120 (5) ◽  
pp. 1109-1121 ◽  
Author(s):  
J. Wallin ◽  
J. Wilting ◽  
H. Koseki ◽  
R. Fritsch ◽  
B. Christ ◽  
...  
Keyword(s):  
Proximal Part ◽  
Axial Skeleton ◽  
Intervertebral Discs ◽  
Paraxial Mesoderm ◽  
Single Amino Acid ◽  
Lumbar Region ◽  
Entire Axis ◽  
Mouse Mutants ◽  
Column Formation

Previous studies have identified a single amino-acid substitution in the transcriptional regulator Pax-1 as the cause of the mouse skeletal mutant undulated (un). To evaluate the role of Pax-1 in the formation of the axial skeleton we have studied Pax-1 protein expression in early sclerotome cells and during subsequent embryonic development, and we have characterized the phenotype of three different Pax-1 mouse mutants, un, undulated-extensive (unex) and Undulated short-tail (Uns). In the Uns mutation the whole Pax-1 locus is deleted, resulting in the complete absence of Pax-1 protein in these mice. The other two genotypes are interpreted as hypomorphs. We conclude that Pax-1 is necessary for normal vertebral column formation along the entire axis, although the severity of the phenotype is strongest in the lumbar region and the tail. Pax-1-deficient mice lack vertebral bodies and intervertebral discs. The proximal part of the ribs and the rib homologues are also missing or severely malformed, whereas neural arches are nearly normal. Pax-1 is thus required for the development of the ventral parts of vertebrae. Embryonic analyses reveal that although sclerotomes are formed in mutant embryos, abnormalities can be detected from day 10.5 p.c. onwards. The phenotypic analyses also suggest that the notochord still influences vertebral body formation some days after the sclerotomes are formed. Furthermore, the notochord diameter is larger in mutant embryos from day 12 p.c., due to increased cell proliferation. In the strongly affected genotypes the notochord persists as a rod-like structure and the nucleus pulposus is never properly formed. Since the notochord is Pax-1-negative these findings suggest a bidirectional interaction between notochord and paraxial mesoderm. The availability of these Pax-1 mutant alleles permitted us to define an early role for Pax-1 in sclerotome patterning as well as a late role in intervertebral disc development. Our observations suggest that Pax-1 function is required for essential steps in ventral sclerotome differentiation, i.e. for the transition from the mesenchymal stage to the onset of chondrogenesis.

scholarly journals A comparative analysis of hair morphology of wild and domestic ungulate prey species of Leopard Panthera pardus fusca (Mammalia: Carnivora: Felidae) from Goa, India

2019 ◽  
Vol 11 (15) ◽  
pp. 14971-14978
Author(s):  
Bipin S. Phal Desai ◽  
Avelyno H. D'costa ◽  
S.K. Shyama
Keyword(s):  
Distal Part ◽  
Prey Species ◽  
Feeding Habits ◽  
Proximal Part ◽  
Diet Analysis ◽  
Medial Part ◽  
Wave Type ◽  
Wild Ungulate ◽  
Hair Morphology ◽  
Study Results

Guard hairs were collected from four live domesticated ungulate species and shed guard hairs of six wild ungulate species from zoo captive animals from five individuals each.  Photographic reference was prepared showing analytic features of hair characteristics.  Study results were analysed and cuticle and medulla patterns were identified along with pigmentation features from the literature available for wild and domestic ungulates from India and abroad.  Clear and easily distinguishable morphological characters of hair medulla and cuticle were used in the present study.  Scat analysis of big cats used in this study is easy, speedy and efficient which can be used in routine investigations related to wildlife, crime forensics as well as human animal conflicts by studying carnivore feeding habits.  In a majority of the animal species, the distal part of the hair showed maximum variation from the rest of the hair portions.  The cuticle scales were imbricate in all tested animals.  Scale position in almost all the tested animals was transversal except in goat (proximal part and medial part) and mouse deer (Distal part).  Majority of the species showed smooth margins at proximal and medial part.  Whereas the distal part scale margin was crenate and rippled in appearance the proximal part and medial part of hair of the majority of sampled animals showed a regular wave -type scale pattern whereas the distal part of hair showed irregular wave-type scale pattern in dominance.  The composition of the medulla was multicellular in all the sampled deer species.  Only the cow calf’s hair medulla was unicellular and uniseriate in appearance.  A comparison of the hair of the domestic pig with that of the wild boar and gaur hair with that of cow calf and buffalo calf hair was made for the first time in the present study. Similarly goat hair morphology can also be differentiated from other cervids in this study.  Medulla and cuticle characters in combination with each other can help differentiate wild ungulate species from the domestic ones since these wild ungulate species are frequently involved in hunting crime investigations.  Therefore, the photographic reference presented in this study can be used in wildlife forensic science as well as predator diet analysis as an appropriate reference for prey species identification. 

scholarly journals Stratigraphic revision and reconstruction of the deep-sea fan of the Voirons Flysch (Voirons Nappe, Chablais Prealps)

2021 ◽  
Vol 114 (1) ◽  
Author(s):  
Jérémy Ragusa ◽  
Lina Maria Ospina-Ostios ◽  
Pascal Kindler ◽  
Mario Sartori
Keyword(s):  
Deep Sea ◽  
Distal Part ◽  
Accretionary Prism ◽  
Proximal Part ◽  
Late Eocene ◽  
Lithostratigraphic Units ◽  
Stratigraphic Record ◽  
Sea Fan ◽  
Stratigraphic Evolution ◽  
Depositional Setting

AbstractThe Voirons Flysch (Caron in Eclogae Geologicae Helvetiae 69:297–308, 1976), is a flysch sequence aggregated into the sedimentary accretionary prism of the Chablais and Swiss Prealps. Its palaeogeographic location is still debated (South Piemont or Valais realm). We herein present a stratigraphic revision of the westernmost unit of the former Gurnigel Nappe sensu Caron (Eclogae Geologicae Helvetiae 69:297–308, 1976): the Voirons Flysch. This flysch is subdivided into three lithostratigraphic units at the formation level (the Voirons Sandstone, the Vouan Conglomerate, the Boëge Marl), with an additional unit (Bruant Sandstone) of uncertain attribution, ranging from the early Eocene to probably the late Eocene. We further propose a new model of the depositional setting of the deep-sea of the Voirons Flysch based on palaeocurrent directions, the overall geometry and sedimentary features. This model depicts an eastward deflected deep-sea fan. The stratigraphic record of the proximal part of this fan is fairly complete in the Voirons area, whereas its most distal part is only represented by one small exposure of thinly bedded sandstones in the Fenalet quarry. The stratigraphic evolution of the Voirons Flysch shows two major disruptions of the detrital sedimentation at the transition between Voirons Sandstone—Vouan Conglomerate and Vouan Conglomerate—Boëge Marl. The cause of these disturbances has to be constrained in the framework of the palaeogeographic location of the Voirons Flysch.

Regulation of Pax-3 expression in the dermomyotome and its role in muscle development

Development ◽  
1994 ◽  
Vol 120 (4) ◽  
pp. 957-971 ◽  
Author(s):  
M. Goulding ◽  
A. Lumsden ◽  
A.J. Paquette
Keyword(s):  
Transcription Factors ◽  
Muscle Development ◽  
Cell Types ◽  
Axial Skeleton ◽  
Mouse Embryos ◽  
Related Gene ◽  
Paired Domain ◽  
Trunk Musculature ◽  
Somitic Mesoderm

The segmented mesoderm in vertebrates gives rise to a variety of cell types in the embryo including the axial skeleton and muscle. A number of transcription factors containing a paired domain (Pax proteins) are expressed in the segmented mesoderm during embryogenesis. These include Pax-3 and a closely related gene, Pax-7, both of which are expressed in the segmental plate and in the dermomyotome. In this paper, we show that signals from the notochord pattern the expression of Pax-3, Pax-7 and Pax-9 in somites and the subsequent differentiation of cell types that arise from the somitic mesoderm. We directly assess the role of the Pax-3 gene in the differentiation of cell types derived from the dermomyotome by analyzing the development of muscle in splotch mouse embryos which lack a functional Pax-3 gene. A population of Pax-3-expressing cells derived from the dermomyotome that normally migrate into the limb are absent in homozygous splotch embryos and, as a result, limb muscles are lost. No abnormalities were detected in the trunk musculature of splotch embryos indicating that Pax-3 is necessary for the development of the limb but not trunk muscle.

Retrospective analysis of the appendiceal neoplasms: sampling technique may influence neoplasm detection

2021 ◽  
pp. postgradmedj-2021-141244
Author(s):  
Gizem Issin ◽  
Fatih Demir ◽  
Hasan Aktug Simsek ◽  
Diren Vuslat Cagatay ◽  
Mahir Tayfur ◽  
...  
Keyword(s):  
Retrospective Analysis ◽  
Distal Part ◽  
Histopathological Examination ◽  
Small Diameter ◽  
Sampling Technique ◽  
Proximal Part ◽  
Longitudinal Section ◽  
Appendiceal Neoplasms ◽  
Macroscopic Findings ◽  
Distal Section

Background and aimsAppendiceal neoplasms are uncommon entities that are usually determined incidentally during the histopathological examination. Different techniques used for the macroscopic sampling of appendectomy material may affect the determinating neoplasms.Materials and methodsH&E-stained slides of 1280 cases who underwent appendectomy between 2013 and 2018 were reviewed retrospectively for histopathological features.ResultsNeoplasms were determined in 28 cases (3.09%); 1 lesion was observed in the proximal part of the appendix, 1 covering the entire length from proximal to distal and 26 in the distal part. In the 26 cases that observed in the distal part, the lesion was seen on both sides of the longitudinal section of the distal appendix in 20 cases, while it was seen on only one distal longitudinal section in the remaining 6 cases.ConclusionThe vast majority of appendiceal neoplasms are seen in the distal part of the appendix, and, in some cases, neoplasms might be seen on only one side of the distal section. Sampling only one-half of the distal part of the appendix, where tumours are most often observed, could result in some neoplasms being missed. Therefore, sampling the whole distal part would be more beneficial to determine small diameter tumours that do not create macroscopic findings.

Inspiratory elevation of the ribs in the dog: primary role of the parasternals [published errata appear in J Appl Physiol 1991 Aug;71(2):following Table of Contents and 1991 Dec;71(6):following Author Index]

1991 ◽  
Vol 70 (4) ◽  
pp. 1447-1455 ◽  
Author(s):  
A. De Troyer
Keyword(s):  
Quantitative Analysis ◽  
Axial Displacement ◽  
The Other ◽  
Primary Role ◽  
Intercostal Muscles ◽  
The Third ◽  
Inspiratory Activity ◽  
Fourth Rib

To assess the relative contributions of the different groups of inspiratory intercostal muscles to the cranial motion of the ribs in the dog, we have measured the axial displacement of the fourth rib and recorded the electromyograms of the parasternal intercostal, external intercostal, and levator costae in the third interspace in 15 anesthetized animals breathing at rest. In eight animals, the parasternal intercostals were denervated in interspaces 1-5. This procedure caused a marked increase in the amount of external intercostal and levator costae inspiratory activity, and yet the inspiratory cranial motion of the rib was reduced by 55%. On the other hand, the external intercostals in interspaces 1-5 were sectioned in seven animals, and the reduction in the cranial rib motion was only 22%; the amount of parasternal and levator costae activity, however, was unchanged. When the parasternals in these animals were subsequently denervated, the levator costae inspiratory activity increased markedly, but the inspiratory cranial motion of the rib was abolished or reversed into an inspiratory caudal motion. These studies thus confirm that, in the dog breathing at rest, the parasternal intercostals have a larger role than the external intercostals and levator costae in causing the cranial motion of the ribs during inspiration. A quantitative analysis suggests that the parasternal contribution is approximately 80%.

Uncx4.1 is required for the formation of the pedicles and proximal ribs and acts upstream of Pax9

Development ◽  
2000 ◽  
Vol 127 (11) ◽  
pp. 2251-2258 ◽  
Author(s):  
A. Mansouri ◽  
A.K. Voss ◽  
T. Thomas ◽  
Y. Yokota ◽  
P. Gruss
Keyword(s):  
Cell Adhesion ◽  
Dorsal Root Ganglia ◽  
Dorsal Root ◽  
Homeobox Gene ◽  
Axial Skeleton ◽  
Adhesion Properties ◽  
Marker Analysis ◽  
Targeted Mutation ◽  
Differential Cell

The expression of the homeobox gene Uncx4.1 in the somite is restricted to the caudal half of the newly formed somite and sclerotome. Here we show that mice with a targeted mutation of the Uncx4.1 gene exhibit defects in the axial skeleton and ribs. In the absence of Uncx4.1, pedicles of the neural arches and proximal ribs are not formed. In addition, dorsal root ganglia are disorganized. Histological and marker analysis revealed that Uncx4.1 is not necessary for somite segmentation. It is required to maintain the condensation of the caudal half-sclerotome, from which the missing skeletal elements are derived. The loss of proximal ribs in Pax1/Pax9 double mutants and the data presented here argue for a role of Uncx4.1 upstream of Pax9 in the caudolateral sclerotome. Our results further indicate that Uncx4.1 may be involved in the differential cell adhesion properties of the somite.

The paired homeobox gene Uncx4.1 specifies pedicles, transverse processes and proximal ribs of the vertebral column

Development ◽  
2000 ◽  
Vol 127 (11) ◽  
pp. 2259-2267 ◽  
Author(s):  
M. Leitges ◽  
L. Neidhardt ◽  
B. Haenig ◽  
B.G. Herrmann ◽  
A. Kispert
Keyword(s):  
Transcription Factor ◽  
Vertebral Column ◽  
Cell Mass ◽  
Homeobox Gene ◽  
Mesenchymal Cell ◽  
Axial Skeleton ◽  
Intervertebral Discs ◽  
Medial Part ◽  
Targeted Mutation ◽  
Vertebral Bodies

The axial skeleton develops from the sclerotome, a mesenchymal cell mass derived from the ventral halves of the somites, segmentally repeated units located on either side of the neural tube. Cells from the medial part of the sclerotome form the axial perichondral tube, which gives rise to vertebral bodies and intervertebral discs; the lateral regions of the sclerotome will form the vertebral arches and ribs. Mesenchymal sclerotome cells condense and differentiate into chondrocytes to form a cartilaginous pre-skeleton that is later replaced by bone tissue. Uncx4.1 is a paired type homeodomain transcription factor expressed in a dynamic pattern in the somite and sclerotome. Here we show that mice homozygous for a targeted mutation of the Uncx4.1 gene die perinatally and exhibit severe malformations of the axial skeleton. Pedicles, transverse processes and proximal ribs, elements derived from the lateral sclerotome, are lacking along the entire length of the vertebral column. The mesenchymal anlagen for these elements are formed initially, but condensation and chondrogenesis do not occur. Hence, Uncx4.1 is required for the maintenance and differentiation of particular elements of the axial skeleton.

Regional differences in potassium content of smooth muscle from opossum esophagus.

1978 ◽  
Vol 235 (6) ◽  
pp. E709
Author(s):  
K Schulze ◽  
J J Hajjar ◽  
J Christensen
Keyword(s):  
Smooth Muscle ◽  
Distal Part ◽  
Proximal Part ◽  
Distal Segment ◽  
Intracellular Concentration ◽  
Potassium Content ◽  
Intracellular Potassium ◽  
The Mean ◽  
Intracellular Potassium Concentration ◽  
Space Volume

Strips from the proximal part of the smooth muscle segment of opossum esophagus have a significantly higher potassium content (50 +/- 3 meq/kg) than those from the distal part (38 +/- 3 meq/kg). There are no significant differences between the two regions in content of sodium (65 +/- 4 meq/kg in proximal, 71 +/- 3 meq/kg in distal) or chloride (48 +/- 10 meq/kg in proximal, 42 +/- 5 meq/ kg in distal). The mean [14C]inulin uptake is 240 +/- 10 ml/kg in both proximal and distal strips. [14C]polyethylene glycol uptake is smaller and [14C]sucrose and [14C]mannitol uptake in both areas are larger than that of inulin. Intracellular potassium concentration (based on the inulin uptake as an estimate of the extracellular space volume) is significantly higher proximally (71 +/- 3 mM) than distally (52 +/- mM). Ouabain, 10(-4) M, increases the intracellular concentration of sodium and decreases the intracellular concentration of potassium in both the proximal and distal segment. The efflux of 86Rb, measured by a washout technique, is higher in the distal than in the proximal smooth muscle segment. A difference in membrane permeability to rubidium and hence, potassium between proximal and distal smooth muscle segments may account in part for the different intracellular potassium concentrations.

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