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The glycosaminoglycans of the fibrous cartilage of temporomandibular articular discs from rat, rabbit, dog and monkey have been separated by means of cellulose acetate membrane electrophoresis on a micro scale. The total glycosaminoglycan amount present in these tissues was found to be 1.8, 1.8, 1.4 and 1.2 μg uronic acid, respectively, per mg tissue wet weight. Two major glycosaminoglycan fractions with the electrophoretic mobility of hyaluronate and dermatan sulfate were present, with the latter predominating. [ABSTRACT FROM AUTHOR]

the presence of cell-mediated immunity and the concurrent absence of humeral immunity to human cartilage proteoglycan are demonstrated in two cases of relapsing polychondritis compared with nine control subjects with other rheumatic diseases. Two in vitro tests have been applied to study each type of immunity. [ABSTRACT FROM AUTHOR]

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, , 726-731. The respiratory function of a patient with relapsing polychondritis is described. He had severe airflow obstruction due to disease of both the extra and intrathoracic large airways. Evidence of small airways disease was lacking. The airflow obstruction was probably due to a combination of structural narrowing and an enhanced dynamic effect. Despite the severity of his disease the patient's exercise capacity was only slightly reduced but he developed carbon dioxide retention on exercise. Involvement of the airways is a common feature of this rare disease and demands full physiological and radiographic assessment if tracheostomy or other surgical procedure is contemplated. [ABSTRACT FROM PUBLISHER]

Several partially purified preparations of NSILA-S were tested for sulfation activity on rat and chicken embryo cartilage. A clearcut stimulation was obtained with as little as 0.1 μU/ml and a near maximal effect with 10 μU/ml. In no instance could sulfation activity be dissociated from NSILA-S. It is, therefore, likely that NSILA-S and sulfation activity are exerted by one and the same molecule. It is, however, compatible with our results and those from other laboratories that still other substances with sulfation activity besides NSILA-S may be present in serum. Morell's findings [7, 8] according to which NSILA-S stimulates growth and metabolism of chicken embryo fibroblasts and our results on NSILA-S stimulation of sulfate incorporation into cartilage point to a possible physiological role of NSILA-S as a growth factor. [ABSTRACT FROM AUTHOR]

Histological, histochemical, and ultrastructural investigations have been carried out on ageing costal and tracheal cartilage of rats. The following age groups of animals have been studied: 1, 7, 14, 20, 30, 45, 75 days, 6 months, and 2 years. Ageing induces cellular changes which are represented by a reduction in the number of chondrocytes, a progressive increase in glycogen deposition, and processes of degeneration, the most frequent of which is the accumulation of lipidic material within large cytoplasmic vacuoles. Changes in the intercellular matrix become evident after 20 days in costal cartilage and after 30 days in tracheal cartilage. Chondroitin sulphate decreases while keratan sulphate, whose presence is limited to the territorial matrix, increases. Glycoproteins increase slightly in young animals and then remain constant; they decrease in the subperichondrial areas in old animals. Ultrastructurally, the matrix of cartilage of young animals contains thin collagen fibrils, most of which have no periodic banding. Roundish electron dense granules are associated with these fibrils. Irregular filaments associated with small electron-dense circular bodies are present around chondrocytes as well as within cytoplasmic vacuoles. With increasing age, and coincident with the reduction of chondroitin sulphate, the thickness of collagen fibrils increases, their period becomes evident, and the associated matrix granules decrease in number and size. Areas containing these fibrils undergo calcification, which frequently starts within roundish bodies of cellular origin. Collagen fibrils with a period of 640 Å but a highly variable thickness are often present in cartilage of adult and old rats. These fibrils seem to be due to an abnormal synthetic activity of chondrocytes. [ABSTRACT FROM AUTHOR]

The nature of the collagen in embryonic and postnatal bovine epiphyseal cartilage was studied by amino acid analysis, extraction in denaturants, and extraction in denaturants after prior digestion of the cartilage with pepsin. Components of both Type I collagen and Type II collagen were isolated by molecular sieve filtration from the gelatin extracted from 4-5 month old embryonic bovine epiphyseal cartilage, and characterized by their behavior during ion exchange chromatography, amino acid composition and their content of hydroxylysine and glycosydically substituted hydroxylysine residues. Type I collagen accounted for about one-third of the total collagen content of epiphyseal cartilage. It was preferentially extracted in denaturant salts, whilst Type II collagen, essentially insoluble in denaturants, could be extracted from the cartilage only after prior digestion of the cartilage with pepsin. The marked preponderance of α components compared with higher molecular weight polymers in the extracted Type I gelatin suggested a paucity of intramolecular crosslinkages, and the lability of the intermolecular crosslinks to denaturants at neutral pH, suggests that the intermolecular, aldehyde-derived crosslinks of Type, I collagen in cartilage are similar to those in the Type I collagen of bone rather than those present in the Type I collagen of skin and other non-mineralized connective tissues. The marked differences in the solubility properties of Type I and Type II collagens of cartilage suggests that the stability and possibly the chemical nature of the intermolecular crosslinkages in Type II collagen, as well as the number of intramolecular crosslinkages, differs in the two types of collagen present in cartilage. [ABSTRACT FROM AUTHOR]

Amino acid analyses of carefully dissected samples of the articular cartilage of postnatal chickens indicates the presence of significant amounts of a collagen with a low hydroxylysine content. It was found that 9 M LiCl solutions preferentially extract the components of a collagen whose components when identified by ion exchange chromatography and amino-acid analyses, established that they were derived from Type I collagen. Type II collagen was essentially insoluble in solutions of 9 M LiCl, but could be solubilized in 4 M CaCl after prior treatment of the cartilage with pepsin. The αl (II) components were then isolated and characterized by their behavior during ion exchange chromatography and by their amino acid composition. The findings establish that the articular cartilage of postnatal chickens contains substantial amounts of Type I collagen and suggest that the nature and stability of the crosslinkages in Type I collagen of cartilage differs significantly from those of Type II collagen of cartilage. Moreover, it is also postulated that the nature of the major intermolecular cross-linkages in the Type I collagen of cartilage are similar to those present in Type I collagen of bone rather than those present in the Type I collabens of skin and other connective tissues. [ABSTRACT FROM AUTHOR]

Iliac crest cartilage biopsies from five children with spondyloepiphyseal dysplasia congenita contained increased amounts of chondroitin-6-sulfate and keratan sulfate. The increase was similar to that observed in the cartilage of patients with Morquio's disease. However, unlike patients with Morquio's disease, those with spondyloepiphyseal dysplasia congenita did not excrete an abnormal amount of keratan sulfate in urine. Spondyloepiphyseal dysplasia congenita can be considered a mucopolysaccharidosis without mucopolysacchariduria. [ABSTRACT FROM AUTHOR]

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Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The mylohyoid bridge occurs in between 1 and 60%, of individuals among various groups of man. The precursor of this bridge is a membrane continuous proximally with the sphenomandibular ligament and stretching the length of the mylohyoid groove medial to its contained neurovascular structures. The membrane and its bony variant may be derived from Meckel's cartilage. [ABSTRACT FROM AUTHOR]

Ninety-six temporomandibular joint disks obtained at autopsy from subjects aged 1 day to 93 years of age and divided into three groups according to dental status were examined microradiographically for calcification. The central part of the disks showed no calcifications in individuals less than 30 years old, and only a few in persons above 30 years with a good dental status, while the occurrence was much greater in patients who had lost many or all of their teeth. In the peripheral part of the disk there were occasional calcifications already in children, and in elderly individuals the calcifications were more common, but the frequency did not appear to vary with the number of residual natural teeth or with the degree of arthrosis of the temporomandibular joint. [ABSTRACT FROM AUTHOR]

The light and electron rnicroscopic appearances of an atypical calcifying odontogenic mandibular tumor containing "amyloid" are presented. In a part of the tumor, PAS-reactive hyalin cosinophilic material which showed green dichroism by polarized light after Congo Red staining, and also hematoxylinophilic mineralized portions were found. By electron microscopy the hyalin material revealed a fibrillar structure. The fibrils had a median diameter of 100 Å, and were short and curved with some apparent outer nodularity. They differed morphologically from other unidentified extracellular and intracellular densely packed fibrils of about 85Å in diameter, from collagen fibers and from a small number of elastic fibers found in the connective tissue. Apparent calcification had occurred in aggregates of the 100 Å fibrils to produce a linear and angulated electron-dense front. Calcification within epithelial cells of the tumor, and calcification in irregular foci around collagen fibers were also found. Quite different histopathological appearances were noted by light microscopy in different parts of the tumor. An anterior region contained numerous islands with large areas of odontogenic epithelium with peripheral ametoblast-Like cells and also solid sheets of cuboidal epithelial cells resembling in some ways those of the calcifying epithelial odontogenic tumor. The upper or posterior region of the tumor contained marked cavernous hemangioniatous elements separated by a loose and often myxoid stroma. Metaplastic cartilage formation had occurred in one part of it. The third molar tooth was located near the coronoid notch. The tumor, although not precisely classified, appeared to be an atypical ameloblastic libro-odontoma. [ABSTRACT FROM AUTHOR]

Rats injected with syngeneic chondrocytes or cartilage shavings develop autoreactivity as assayed by the leucocyte migration inhibition test. It is suggested that chondrocyte specific differentiation antigen(s), normally sequestered from the immune system, once exposed experimentally by enzyme treatment or in some human pathological situations are recognized as foreign immunogens and induce a lymphocyte response. [ABSTRACT FROM AUTHOR]

There is a broad sphenethmoidal commissure connecting the paranasal to the orbitonasal cartilage. A single epiphaneal foramen is observed between the left parieto-tectal and paranasal cartilages. Only two ethmoturbinals are present in the nasal capsule, while multiple olfactory foramina transmit the filaments of the olfactory nerves. A complete zona annularis is lacking in Galago. The orbitoparietal as well as the alicochlear commissures are absent. A foramen hypophyseos is present and the course of the notochord is complicated. There is a broad basicapsular commissure. In the auditory capsule a processus recessus and the lateral prefacial commissure are absent. [ABSTRACT FROM AUTHOR]

The article focuses on the discussion on chondrocranium of Lacertilia. Tropiocolotes tripolitanus is an extremely small lizard, belonging to family Geckonidac. Like other geckos, it can live very well and lay eggs very easily in captivity. Its eggs usually hatch in the normal atmosphere without special incubation. The chondrocranium is studied by the usual method of serial transverse sections and graphic reconstructions made from them. The embryos are stained in toto with Borax carmine and, after sectioning, the sections are counterstained with Picroindigo-carmine.

The article provides information on ontogeny of the chondral skull in Characidae. The author discusses the internal and external morphology of the skull. Information is given on polar cartilages, otic cartilages, blastema cells, morphology of the mandibular arch, hyal arch, and caudal portion of premandibular somites.

The article presents a study on the nasal capsule of Bos Chondrocranium of Ovis at its stage of development. The nasal capsule of Ovis is made up of the nasal septum. The palatine cartilage depicts the primitive cartilaginous nasal floor of Ovis which is also found in other mammals. A series of articles on the nasal capsule of different mammals showed the paraseptal cartilage composed of the Jacobson's organ.

1. The skull and weberian apparatus of twelve genera of Gobioninae (Cyprinidae) has been examined by me. 2. The three genera Saurogobio, Abbottina and Pseudogobio show elongated second preethmoid cartilages; in the other members studied, they are very much shorter. In Gatostonius, the second preethmoid is elongated. 3. The median rostral is elongated in Saurogobio, Abbottina, Pseudogobio and Gobiobotia. 4. The anterior portion of the ethmoid-prevomer shows a ventral flexure in Saurogobio, Abbottina and Pseudogobio as in Catostomus. In Gobiobotia, it is not seen. 5. Saurogobio, Abbottina, Pseudogobio and Gobiobotia show fontanel or fontanelles in the roof as in Gatostonius. 6. The supraorbital is either absent (Saurogobio, Abbottina, Corieus) or diminutive (Gobio, Pseudogobio) ; in other genera examined, it is well developed. In Catostomus, a supraorbital is absent. 7. In the occipital region, the occipital sensory canal passes through the supraoccipital in Saurogobio, Abbottina, Pseudogobio and Gobiobotia; in the other genera, it passes through the parietals. 8. One or two rows of pharyngeal teeth are more commonly met with in the Gobioninae; Hemibarbus is the only one with three rows of teeth. 9. The gasbladder is enclosed in a bony capsule only in Saurogobio and Gobiobotia but the structure of the capsule differs in them. The capsule of Gobiobotia apparently resembles that of the Nemachilinae (Cobitidae) but the second pair of dorsal ribs does not contribute towards the formation of capsular wall. 10. The weberian apparatus of the Gobioninae resembles that of Cyprininae; in Saurogobio and Gobiobotia, the transformator process of the tripus is absent on account of the development of a capsule. 11. Saurogobio, Abbottina and Pseudogobio in exhibiting a large number of catostomid features, probably represent a grotip of gudgeons more nearly related to the Catostomidae. 12. Gobiobotia is not a loach (Cobitidae) and shows certain specializations and it may be treated as a type of a group under Gobioninae; Saurogobio, Abbottina and Pseudogobio form a second group and the rest may conveniently be put under a third group. [ABSTRACT FROM AUTHOR]

Long spacing segment crystallites, prepared from soluble chick bone and skin collagen with the chain composition [α1(I)]2α2 and soluble chick cartilage collagen with a chain composition [α1(II)]3. were compared in electron microscope studies after staining with phosphotungstic acid and uranyl acetate. Although comparison of bone and skin collagen long-spacing segment preparations with similar preparations of cartilage collagen revealed several differences in intensities of cross-striation bands, no differences in the positions of the cross-striation bands could be observed in the three preparations, indicating that the distribution of polar and apolar regions along the cartilage collagen molecule is marked]y similar to that of molecules derived from bone and 8km collagen. Comparison of segment long-spacing crystallites prepared from the various collagens also showed that the cartilage collagen is longer than the bone or skin collagen molecule by about 10-12 nm. The additional length of the cartilage collagen molecule is clearly discerned as an extra band located in the COOH-terminal region, and is removed by treatment of the collagen with pepsin prior to precipitation as segment long-spacing crystallites, indicating that this region contains one or more sequences in which the collagen helix cannot form. In studies on fibrils formed by the three collagen preparations, it was noted that bone and skin collagen could be readily precipitated as broad, well-structured fibrils in which a banding pattern characteristic of native type fibrils could be easily observed. On the other hand, carriage collagen precipitated under identical conditions, formed slightly smaller fibrils in which a banding pattern commonly associated with native type collagen fibrils was only faintly visible in certain segments of the fibrils. [ABSTRACT FROM AUTHOR]

The intradermal as well as intraperitoneal injection of zirconium salts in CBA/J mice produced local foreign body type granulomas which regularly persisted for over eight months. None of the animals exhibited evidence of the late delayed immune type of epithelioid cell granulomatous hypersensitivity such as has been induced experimentally in man. Benign chondromas developed locally in the ear cartilage plate in half of the mice who had received zirconium injections in this area. [ABSTRACT FROM AUTHOR]

Twenty-five young adult Sprague-Dawley rats were injured at the gingiva mesial to the maxillary left and right first molars. The injury at the left first molar received daily applications of cartilage microparticles for five days following wounding. The right wound site served as the untreated control. Animals were sacrificed at varying time intervals over a twenty-eight days experimental period and the maxillae were prepared for histologic study. Cartilage treated wounds showed an initial increase in cellular activity and a subsequent delay in connective tissue maturation, Crestal osteogenesis appeared to be delayed in the cartilage treated areas. The presence of cartilage micro-particles did not affect the apical migration of the epithelial attachment which followed gingival injury. [ABSTRACT FROM AUTHOR]

The differentiation of cartilage in the external ear of the rat proceeds in four steps. Each of them is characterized by a specific biosynthetic activity of the chondroblast resulting in the appearance of a new structural component of the tissue: collagen fibrils, elastin fibers, cartilage ground substance and intracellular fat droplets. As a structurally and developmentally well-defined 'subspecies' of cartilage, this tissue might serve as a suitable object for the experimental approach to some essential problems in histodifferentiation. [ABSTRACT FROM AUTHOR]

A study was undertaken to clarify the pathogenesis of tracheal stenosis complicating the use of cuffed tracheostomy tubes, a complication of increasing clinical significance. Tracheostomy with a cuffed inflated tube was established in dogs and was maintained for two weeks. The effects of tracheostomy were assessed by bronchoscopy, tracheography, and histology at the time of killing, eight weeks after extubation. Animals were divided into four groups, each mimicking a common clinical situation. A control group had uncuffed tubes. A method was designed to determine the pressure developed between the cuff and the tracheal wall. Cuff inflation was maintained at low pressure and at high pressure in a second and third group of animals. A fourth group of animals received prednisone during the two weeks of low pressure inflation. Tracheal stenosis, resembling the defect we have encountered in humans, occurred at the tracheostome in all animals. The greater the diameter of the tracheostomy tube relative to the tracheal diameter, the more severe was the resultant stenosis. Greater degrees of tracheal injury occurred with cuffed than with uncuffed tubes, and still greater injury was observed in animals in which high inflationary pressures or steroids were used. These findings suggest that tracheal stenosis complicating cuffed tracheostomy tubes is the result of ischaemic death of tracheal cartilage due to pressure and infection. Steroids used concomitantly accelerate these changes. [ABSTRACT FROM PUBLISHER]

The deformity of pectus excavatum is caused by a negative pressure in the anterior mediastinum sucking in the body of the sternum. This is usually due to the heart lying on the left side, leaving the mediastinum empty so that the sternum and costal cartilages are sucked in to fill the empty space. The operation consists of excising the deformed cartilages, mobilizing the sternum, and suturing the pericardial sac into a central position which corrects the deformity. [ABSTRACT FROM PUBLISHER]

The fine structure of the upper tibial epiphyseal plate of the normal guinea pig has been investigated. On morphological and functional grounds this cartilage can be divided into four zones. In all zones the chondrocytes are distributed in an electronlucent organic matrix composed of thin collagenous fibrils and small non-membrane-bounded granules representing proteoglycans. [ABSTRACT FROM AUTHOR]

The cartilage matrix in which the early calcium salts are deposited has been studied in the tibial epiphyses and in the costo-chondral junctions of 30-day-old guinea pigs. The results may be summarized as follows: (1) Structures of globular shape ('globules') are to be found throughout the entire epiphyseal plate. (2) They have a homogeneous matrix and are bounded by a membrane. (3) Early calcification occurs in globules. Calcification of collagen fibrils seems to occur later. (4) The earliest mineral deposited would seem to consist of tiny granules about 20 Å in diameter. Then apatite crystals are laid down, initially in small clusters and later filling the globules completely. (5) The globules are strongly osmiophilic. They seem to contain a fair amount of neutral polysaccharides, but no acid polysaccharides except a coating on their outer membrane. Hyaluronidase digestion does not affect globules. Papain digestion makes them more reactive to uranium and lead. (6) Globules are of cellular origin but they are almost certainly not pre-formed in the chondrocytes. Finally, the present paper advances the hypothesis that some globules derive from degenerating chondrocytes and others from the processes of normal chondrocytes. [ABSTRACT FROM AUTHOR]

The article focuses on the study on the clinical, physical psychological, psychiatric, electrocardiographic and roentological aspects of patient Joseph A., who is suffering from Morquio-Brailford syndrome. It is indicated that the abnormalities found in the bones, cartilage and joints of patient with the rare familial disorder are believed to be pathognomonic. The patient is seen with changes including the short neck appearing sunken into the chest, reduced thorax in terms of height and wedge-like vertebral bodies.

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Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

1. The quantitative distribution of alkaline phosphatase and glucose-6-phosphate dehydrogenase in proliferating and hypertrophic zones of rachitic rat cartilage during healing induced by vitamin D administration or starvation is presented. 2. Alkaline phosphatase activity in the hypertrophic zone is about three times greater than that of the proliferating zone of the normal weanling rat and approximately four times greater in the rachitic rats. 3. Following a single dose of vitamin D (8000 I. U.) there was a significant elevation in alkaline phosphatase activity of the proliferating zone. A less significant increase was observed in the proliferating zone of rats which had breen fasted 48 hours. 4. There was a significant decrease in the alkaline phosphatase activity of the central region of hypertrophic zone of cartilage after vitamin D treatment. No such decrease was observed in the fasted rats. 5. In the normal weanling rat glucose-6-phosphate dehydrogenase (G-6-PDH) activity was greater in the proliferating zone as compared to the hypertrophic zone. In the untreated rachitic rat the enzyme content was about the same in the two zones. 6. Following vitamin D treatment there was an appreciable decrease in the G-6-PDH activity. No such decrease was observed in the fasted rat. [ABSTRACT FROM AUTHOR]

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Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)