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At least 19 recordsLinked to original sources

[Origin and fixation of pyrophosphates in the parietal bones of young rats].

Calvaria from 6 to 13-day-old rats mineralize and bind pyrophosphates which are transferred from nucleotides, as shown by : 1 -- the increase of pyrophosphates in young rat calvaria incubated with nucleoside triphosphate, especially ATP ; 2 -- the more important increase of pyrophosphate content when ATP is renewed in the incubation medium ; and 3 -- binding of [32P] pyrophosphate [beta 32P] ATP. The effect of preheating of calvaria on 32P binding from [beta32P]ATP led us to assume that two systems might be involved in pyrophosphate fixation : a heat-labile, non-specific, phosphatase system, and a heat-stable pyrophosphotransferase system. cAMP increases the pyrophosphate content of calvaria incubated with ATP : that effect may result from either an inhibition of the phosphatase system, or an activation of the pyrophosphotransferase system.

Adenosine Triphosphate

[Ontogenic development of the surface of craniofacial sagittal angular sectors in man and chimpanzee].

By means of a technique for measuring surfaces by direct reading, six angular sectors have been studied (3 for the face and 3 for the skull) at various ontogenic periods of Man, common chimpanzee and dwarf chimpanzee. The growth curves have been drawn for absolute values and for relative values. They show a certain evolutive parallelism between the frontal bone and the parietal bone, and between the face and the mandible, with a special fate for the occipital bone.

Adult

[Double contours and companion shadows in the skull associated with anaemias (author's transl)].

Lateral X-ray pictures of the skull in certain several and chronic disorders of the blood as thalassaemia, congenital haemolytic anaemia, sickle cell anaemia and iron deficiency disease show frequently changes of the outlines of the cranial bones. They consist of a double contour of the outer cranial border and on the interior side below the sagittal sutura of a band-like shadow or of multiple stripes and lines running parallel to the carnial vault. They concern the parietal bones and may extend from the bregma till to the lamda or occupy only a part of this distance. The roentgenological features are due to the enlargement of the crainal bones, the bulging out of both parietal bondes, the sometimes enlarged and deepened borders of the sulcus sagittalis superior and particularly to the furrow and depression on the skull above the sagittal suture caused by the protruding parietal bones on both sides. As these different abnormal structures must be passed by the picturing X-ray, effects of superposition and interference are produced. Longitudinal ridges or bony edges which could explain the roentgenological findings could not be established. Since the peculiar alterations of the cranial bones are mainly found in the mentioned blood disorders, where they are caused by the overgrowing red marrow, they also display the same roentgenological features. These features are, therefore, a characteristic sign of these diseases.

Adolescent

[An infantile skull fracture followed by the enlarging of the fracture line ("enlarging skull fracture") (author's transl)].

We experience sometimes an infantile skull fracture which is followed by the skull fracture line and bulging of the fractured area day by day after the head injury. Since John Howship reported the case of the partial absorption of the right parietal bone, arising from a blow on the head in a child aged 9 month in 1816, this phenomenon was variously described meningocele spuria, traumatic cephalohydrocele, leptomeningeal cyst, fibrosing osteitis, cerebrocranial erosion, traumatic meningocele, die wachsende Schädelfrakture, growing skull fracture, etc. So called "growing skull fracture" has generally the triad of the symptoms which are the parietal skull fracture in infancy or childhood, traumatic dural tears, and subsequent enlargement of the fractures. And it is said that the dural tear is an indispensable condition for the developing of the "growing skull fracture". But we recently had the case of a 14 day old male infant who had neither traumatic dural tear nor subdural hematoma, but the progressive enlarging of the fracture line in the left parietal bone. The authors suggest that there should be the difference between the growing skull fracture (with the dural teat) and the enlarging skull fracture (without the dural tear).

Fractures, Ununited

[Radiological determination of skull thickness and skull thickness increase in patients with severe blood dyscrasias and hyperplasia of the red marrow (author's transl)].

A method is described for measuring the thickness of the cranial bones in x-ray pictures of the skull, which in a reliable way can only be done in the frontal and the parietal bones. From the results, representative and comparable values have been obtained consisting of the mean and maximum thickness of the bones and of the mean deviation of the thickness in the bone. By using these values, the thickness has been determined in normal persons and the increase of thickness established in different patients suffering from a number of blood disorders. A scale of increasing degrees of thickening could be set up ranging form normal conditions to extraordinary enlargement. As the thickening of the bones is due to the hyperactivity of the red marrow contained in the bones, and the increase of thickness depends on the intensity of the overgrowth of the marrow and of the time of its action on the osseous substance, from the thickness of the bones a conclusion can be drawn regarding the presence, the severity and the duration of the existing blood disorder. Since, moreover, the enlargement of the bones is irreversible, an increased thickness of the cranial bones may, in patients without alterations in the blood, point to a former blood disorder.

Adolescent

The functional significance of the squamosal suture in Australopithecus boisei.

A juvenile Australopithecus boisei specimen from the Omo basin, southern Ethiopia, is found to exhibit and extraordinarily large overlap of the temporal squama on the parietal, a phenomenon shared with at least two adult specimens of A. boisei. An attempt is made to interpret the overlap as a structural (bony/ligamentous) adaptation necessitated by the unique combination of certain components of the masticatory system of A. boisei. These are: (1) the massiveness and strength of the temporalis muscle, (2) its relatively anterior location, and (3) the lateral position of the masseter muscle due to the flaring of the zygomatic arches. The effect of the temporalis muscle is to create excessive pressure on the portion of the squamosal suture along the parietal, while the lateral placement of the masseter and the resultant increase of pressure on the temporal squama via the zygomatic arch tend to "loosen" the contact between the temporal and parietal bones.

Animals

Developmental defects in the cranial vault.

The parietal bone seems to be the target for a number of different developmental conditions of the calvaria some of which are congenital whilst others develop in later life. The characteristic radiological patterns of a number of these lesions are described and illustrated, and an attempt is made to correlate the pathology with alterations in bone growth.

Adult

The migration of osteoblasts.

The endocranial matrix surfaces of parietal bones of 2-week old Albino Wistar rats were partly denuded of osteoblasts and then cultured for various periods up to 24 h, in control or PTE-enriched medium. They were examined by scanning electron microscopy and evidence for cell locomotion was found. Osteoblasts traversed the denuded bone surface and cut edges of bone in either medium, and cells also migrated out from vascular channels. Glass spicules were placed on the otherwise undisturbed osteoblast layer in similar organ cultures for 2, 3 or 5 days. Osteoblasts migrated from the bone to populate the glass, negotiating any angle. The cells in PTE-enriched media were always aligned parallel to one another and elongated, tended to align with the edges of the glass and, in time, formed a substrate of aligned fibrils whose axes were parallel to those of the cells. Osteoblasts in control medium on glass showed variable degrees of alignment and elongation and were less influenced by edges of the glass. Non-locomotory, nearly equidiametrical cells on glass in 5d control cultures had formed a substrate of randomly oriented fibrils. Migrating osteoblasts on bone matrix did not have leading edge ruffles; isolated, migrating ones on glass did.

Animals

Transmembrane potentials of osteoblasts.

Transmembrane potentials were recorded in situ from osteoblasts on the parietal bones of albino rat pups, 3 to 24 days of age. Osteoblasts exhibit a uniquely low polarization of their cell membranes (3.93 mV, inside negative). Osteoblasts respond rapidly, but transiently, to parathyroid hormone by depolarization, and to thyrocalcitonin by hyperpolarization.

Animals

[The endocranial parietal vascular traces in the hominid line].

The study of the grooves traced by the middle meningeal veins on the parietal bone or the endocast of Hominid fossils shows different patterns which correspond to each evolutive stage. Height types are characterised among the Hominids (Australopithecines, Archanthropines, Paleanthropines and Neanthropines): I, robust Australopithecine type; II, gracile Australopithecine type; III, earliest Pithecanthropine type; IV, evolved Pithecanthropine type; V, Preneandertal type; VI, neandertal type; VII, Neanthropine type; VIII, modern type.

Biological Evolution

The correlation between permanent septal deformities and nasal trauma during birth.

Both the outer and inner nose as well as the position of the parietal bones of 972 patients at an age of 3 to 82, were examined giving evidence of the configuration of the infant's head at birth and thereby of the "severity" of the birth. In comparison with the sectio-patients the configuration of the infant's head in the birth canal reveals statistically recorded deformations of the outer and inner nose with an obstruction of the nasal breathing in 20% of the patients examined. The degree of the configuration has a definite influence on the degree of the nose deformation. The adjustment of the rotary direction of the infant's head in the 1st and 2nd vertex presentation determines the direction of the nose deformation. The demand of many authors for an immediate rhinological examination and corrections in the newborn child, for instance on the septum, to be performed still in the obstetrical department, must due to our own examinations be advocated.

Adolescent