Rôle du mésoderme somitique dans le développement de la cage thoracique de I'embryon d'oiseau. I. Origine du segment sternal et mécanismes de la différentiation des côtes

Development ◽  
1975 ◽  
Vol 33 (2) ◽  
pp. 291-311
Author(s):  
Alain Chevallier
Keyword(s):  
Chick Embryo ◽  
The Other ◽  
Pectoral Girdle ◽  
Thoracic Region ◽  
Rib Cage ◽  
Intercostal Muscles ◽  
Normal Limits ◽  
Somitic Mesoderm ◽  
Vertebral Segment

Role of the somitic mesoderm in the development of the rib cage of bird embryos. I. Origin of he sternal component and conditions for the development of the ribs The developmental origin of the sternal component of the ribs and the conditions for the development of the rib cage have been elucidated in bird embryos. Experiments consisted in homo- or heterospecific transplantations of 2-day-old quail or chick embryo somitic mesoderm into chick hosts of the same age in ortho- or heterotopic position along the cephalo-caudal axis. Results show that vertebral halves, ribs (not only their vertebral segment, but also their sternal component when they possess one), the trunk and intercostal muscles, as well as at least part of the scapula originate exclusively from the somitic material, while the sternum, ventral muscles and the other parts of the pectoral girdle are derived from the somatopleural mesoderm. The development of the rib basket is subjected to following rules: — only the somitic mesoderm of the prospective thoracic region (somites 19–26) is able togive rise to ribs. — only the somitic mesoderm of the posterior thoracic region (somites 22–26) is able to develop ribs with a sternal component. — the vertebral component of ribs can develop outside the thoracic region. — contrariwise, the sternal component can form only in the vicinity of the sternal anlage, i.e within about three somites in front and rear of the normal limits of the thoracic region. It is concluded that the somitic mesoderm is already regionalized at a stage slightly preceding its metamerization and that the somatopleural territory of the sternum plays a morphogenetic role in the development of the sternal component of ribs, although it does not make a cellular contribution to their construction.

Role of intercostal muscles in the rib cage distortions produced by inspiratory loads

1982 ◽  
Vol 52 (3) ◽  
pp. 517-523 ◽  
Author(s):  
M. G. Sampson ◽  
A. De Troyer
Keyword(s):  
Electrical Activity ◽  
Strong Evidence ◽  
Normal Subjects ◽  
The Other ◽  
Reflex Activity ◽  
Quiet Breathing ◽  
Rib Cage ◽  
Intercostal Muscles ◽  
Inspiratory Activity

We studied the patterns of rib cage (RC) deformation in six normal subjects breathing against different resistive and elastic inspiratory loads, and we examined, with concentric needle electrodes, the role played by the inspiratory intercostal muscles in the development of these patterns. Four of the subjects deformed their RC to a more elliptical shape during loaded inspirations; RC anteroposterior diameter became smaller and RC lateral diameter became larger. The RC deformation increased as the load increased, but it appeared to be independent of the nature of the load. Moreover these deformations were associated with a marked increase in the inspiratory activity of the intercostals situated in the lateral parts of the RC and a striking diminution of the activity in the parasternal area. On the other hand, two subjects invariably breathed along their RC relaxation characteristic, and they showed an increased inspiratory activity in all regions of the intercostal musculature. These findings indicate that 1) the pattern of RC deformation during loaded inspirations is closely related to the activity and coordination of the various inspiratory intercostal muscles, and 2) the parasternal intercostals are not necessarily representative of all the inspiratory intercostals. They are also strong evidence against the concept that the parasternal intercostal electrical activity normally recorded during quiet breathing is an excitatory reflex activity.

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%.

Parasternal and external intercostal responses to various respiratory maneuvers

1992 ◽  
Vol 73 (3) ◽  
pp. 979-986 ◽  
Author(s):  
A. F. DiMarco ◽  
J. R. Romaniuk ◽  
G. S. Supinski
Keyword(s):  
Muscle Length ◽  
Similar Degree ◽  
Intercostal Muscle ◽  
Abdominal Compression ◽  
Similar Extent ◽  
Rib Cage ◽  
Piezoelectric Crystals ◽  
Intercostal Muscles ◽  
Steel Electrodes

Recent studies suggest that the external intercostal (EI) muscles of the upper rib cage, like the parasternals (PA), play an important ventilatory role, even during eupneic breathing. The purpose of the present study was to further assess the ventilatory role of the EI muscles by determining their response to various static and dynamic respiratory maneuvers and comparing them with the better-studied PA muscles. Applied interventions included 1) passive inflation and deflation, 2) abdominal compression, 3) progressive hypercapnia, and 4) response to bilateral cervical phrenicotomy. Studies were performed in 11 mongrel dogs. Electromyographic (EMG) activities were monitored via bipolar stainless steel electrodes. Muscle length (percentage of resting length) was monitored with piezoelectric crystals. With passive rib cage inflation produced either with a volume syringe or abdominal compression, each muscle shortened; with passive deflation, each muscle lengthened. During eupneic breathing, each muscle was electrically active and shortened to a similar degree. In response to progressive hypercapnia, peak EMG of each intercostal muscle increased linearly and to a similar extent. Inspiratory shortening also increased progressively with increasing PCO2, but in a curvilinear fashion with no significant differences in response among intercostal muscles. In response to phrenicotomy, the EMG and degree of inspiratory shortening of each intercostal muscle increased significantly. Again, the response among intercostal muscles was not significantly different.(ABSTRACT TRUNCATED AT 250 WORDS)

Origine des ceintures scapulaires et pelviennes chez l'embryon d'oiseau

Development ◽  
1977 ◽  
Vol 42 (1) ◽  
pp. 275-292
Author(s):  
Par Alain Chevallier
Keyword(s):  
Chick Embryo ◽  
Pelvic Girdle ◽  
The Other ◽  
Limb Musculature ◽  
Lateral Mesoderm ◽  
Somitic Mesoderm

The development and the origin of the pectoral and pelvic girdles have been studied in bird embryos by homo- or heterotopic transplantations of somitic and somatopleural mesoderm. Experiments consisted in implanting a piece of somitic or of somitic and somatopleural mesoderm obtained from a 2- to 2·5-day quail or chick embryo into a chick host of equal age. Results showed that the scapula derives from the somitic mesoderm, while clavicle, coracoid, sternum and pelvic girdle originate from the somatopleural mesoderm. The longitudinal span of the territories of the various skeletal elements, expressed as the number of the corresponding somites, was found to be as follows: scapula 15–24, clavicle 10–15, coracoid 15–17, sternum 12–26, and pelvic girdle 26–32. It was also demonstrated that both somitic and somatopleural mesoderm are regionalized as early as 2 days of incubation, prior to somitic segmentation, with respect to their ability to give rise to the skeletal elements of the girdles. These results were compared to those acquired previously concerning the other morphogenetic potentialities (vertebrae, ribs, limb musculature, dorsal plumage) of the para-axial and lateral mesoderm.

Scanning electron microscopic study of collagen fibrillogenesis and extracellular compartmentalization in the chick embryo tendon

1986 ◽  
Vol 44 ◽  
pp. 208-209
Author(s):  
Grace C.H. Yang
Keyword(s):  
Chick Embryo ◽  
Extracellular Space ◽  
Fibroblast Cell ◽  
Collagen Fibrils ◽  
Electron Microscopic ◽  
Voltage Electron ◽  
Scanning Electron Microscopic Study ◽  
Microscopic Studies ◽  
And Function

The size and organization of collagen fibrils in the extracellular matrix is an important determinant of tissue structure and function. The synthesis and deposition of collagen involves multiple steps which begin within the cell and continue in the extracellular space. High-voltage electron microscopic studies of the chick embryo cornea and tendon suggested that the extracellular space is compartmentalized by the fibroblasts for the regulation of collagen fibril, bundle, and tissue specific macroaggregate formation. The purpose of this study is to gather direct evidence regarding the association of the fibroblast cell surface with newly formed collagen fibrils, and to define the role of the fibroblast in the control and the precise positioning of collagen fibrils, bundles, and macroaggregates during chick tendon development.

Plasma Levels of Protein S, Protein C, and Factor X: Effects of Sex, Hormonal State and Age

1995 ◽  
Vol 74 (05) ◽  
pp. 1271-1275 ◽  
Author(s):  
C M A Henkens ◽  
V J J Bom ◽  
W van der Schaaf ◽  
P M Pelsma ◽  
C Th Smit Sibinga ◽  
...  
Keyword(s):  
Regression Analysis ◽  
Postmenopausal Women ◽  
Protein C ◽  
Blood Donors ◽  
Premenopausal Women ◽  
Protein S ◽  
The Other ◽  
Factor X ◽  
Normal Ranges

SummaryWe measured total and free protein S (PS), protein C (PC) and factor X (FX) in 393 healthy blood donors to assess differences in relation to sex, hormonal state and age. All measured proteins were lower in women as compared to men, as were levels in premenopausal women as compared to postmenopausal women. Multiple regression analysis showed that both age and subgroup (men, pre- and postmenopausal women) were of significance for the levels of total and free PS and PC, the subgroup effect being caused by the differences between the premenopausal women and the other groups. This indicates a role of sex-hormones, most likely estrogens, in the regulation of levels of pro- and anticoagulant factors under physiologic conditions. These differences should be taken into account in daily clinical practice and may necessitate different normal ranges for men, pre- and postmenopausal women.

On the role of the dispute between "non-possessors" and "Josephites" in the culture of Moscow's prediction

1998 ◽  
pp. 61-62
Author(s):  
N. S. Jurtueva
Keyword(s):  
The Other ◽  
Moral Transformation ◽  
15Th Century ◽  
The Future ◽  
Secular Power

In the XIV century. centripetal tendencies began to appear in the Moscow principality. Inside the Russian church, several areas were distinguished. Part of the clergy supported the specificobar form. The other understood the need for transformations in society. As a result, this led to a split in the Russian church in the 15th century for "non-possessors" and "Josephites". The former linked the fate of the future with the ideology of hesychasm and its moral transformation, while the latter sought support in alliance with a strong secular power.

From Container to Claustrum: Projective Identification in Couples

2014 ◽  
Vol 4 (2) ◽  
Author(s):  
Tamara Feldman
Keyword(s):  
Psychological Health ◽  
Projective Identification ◽  
The Self ◽  
The Other ◽  
Intimate Partners ◽  
And Control ◽  
The Relationship ◽  
As If

This paper is a contribution to the growing literature on the role of projective identification in understanding couples' dynamics. Projective identification as a defence is well suited to couples, as intimate partners provide an ideal location to deposit unwanted parts of the self. This paper illustrates how projective identification functions differently depending on the psychological health of the couple. It elucidates how healthier couples use projective identification more as a form of communication, whereas disturbed couples are inclined to employ it to invade and control the other, as captured by Meltzer's concept of "intrusive identification". These different uses of projective identification affect couples' capacities to provide what Bion called "containment". In disturbed couples, partners serve as what Meltzer termed "claustrums" whereby projections are not contained, but imprisoned or entombed in the other. Applying the concept of claustrum helps illuminate common feelings these couples express, such as feeling suffocated, stifled, trapped, held hostage, or feeling as if the relationship is killing them. Finally, this paper presents treatment challenges in working with more disturbed couples.

Thomas More's “rule” of pleasure before, after, and inUtopia

Moreana ◽  
2017 ◽  
Vol 54 (Number 207) (1) ◽  
pp. 36-56
Author(s):  
Gerard Wegemer
Keyword(s):  
Human Nature ◽  
The Other ◽  
Biblical Allusions ◽  
De Officiis

After establishing a context of More's lifelong engagement with the “calculus” of pleasure, this essay shows how the section devoted to the Utopians' pleasure philosophy is structured around five formulations of a “rule” to calculate “true and honest [honesta]” pleasure in ways that playfully imitate and echo the “rule” Cicero formulates several times in De officiis to discern one's duty when there seems to be a conflict between honestas et utilitas. When followed, the Utopian pleasure calculus shows the necessary role of societas, officii, iustitia, caritas, and the other aspects of human nature, most importantly friendship, that Cicero stresses in his rule and that he argued Epicurus ignored. Much of the irony and humor of this section depends on seeing the predominance of Ciceronian vocabulary in Raphael's unusual defense [patrocinium] of pleasure, rather than a Ciceronian defense of duty rooted in honestas. Throughout, however, this essay also shows how More goes beyond Cicero by including Augustinian and biblical allusions to suggest ways that our final end is not as Epicurus or the Stoics or Cicero claim; the language and allusions of this section point to a level of good cheer and care for neighbors and for God in ways quite different from any classical thinker.

BLOCKADE OF THE SURGE OF PROLACTIN AT PRO-OESTRUS BY ADMINISTRATION OF ANTI-OESTROGENIC SUBSTANCE, MER-25

1973 ◽  
Vol 74 (4) ◽  
pp. 769-774 ◽  
Author(s):  
Akira Yokoyama ◽  
Hiroshi Tomogane ◽  
Katuaki Ôta
Keyword(s):  
Strong Evidence ◽  
The Other ◽  
Other Hand

ABSTRACT A non-steroidal oestrogen antagonist, MER-25, was administered to cycling rats for elucidating the role of oestrogen in the surge of prolactin observed on the afternoon of pro-oestrus (POe). In animals injected with 20 mg of MER-25 intramuscularly on the afternoon (16.30 h) of the first day of dioestrus (D-1), the surge of prolactin was blocked while the level of prolactin on the afternoon of POe of these animals was significantly higher than that of the corresponding controls injected with oil. Ovulation was also blocked in these animals treated with the drug on the afternoon of D-l. On the other hand, treatment on the morning (10.30 h) of the 2nd day of dioestrus failed to prevent not only the surge of prolactin but also ovulation. These observations provide strong evidence for the view that oestrogen is responsible for the surge of prolactin on the afternoon of POe, and that the surge is accompanied by that of LH.

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