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  • Bone  (48)
  • Springer  (48)
  • 1980-1984  (16)
  • 1970-1974  (32)
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  • Springer  (48)
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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 12 (1973), S. 73-90 
    ISSN: 1432-0827
    Keywords: Bone ; Mineral ; Properties ; Deproteination ; Hydrazine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Une méthode, utilisant 95% d'hydrazine, permet de déprotéiniser et de déshydrater légèrement l'os dans des conditions presqu'anhydres, avec une élévation de température modérée. Cette méthode ne provoque que des modifications chimiques mineures, sans altération des propriétés structurales de la phase minérale. Les résultats physico-chimiques démontrent que bien que les cristaux d'os de rat sont viosins de cristaux synthétiques témoins constitués dans des milieux, riches en carbonate plutôt qu'en hydroxyde, l'apatite osseux de rat ne parait pas analogue à des modèles cristallins connus ou imaginés. Des déterminations de bande infra-rouge CO 3 2− , réalisées à partir de spectre d'os total, semblent faussées par la présence de bandes d'absorption protéique. L'absorption d'HPO 4 2− est étudiée à l'aide de spectres infra-rouges de minéral osseux de jeunes rats. Des comparaisons détaillées en diffraction par raysons X d'os déprotéinisé de rats, avant et après hydrolyse, démontrent nettement la présence de phosphate de calcium amorphe. La microscopie électronique indique que de petits cristaux d'apatite dans l'os de rat sont susceptibles de contribuer au pool minéral amorphe en diffraction en rayons X. La microscopie électronique montre des plages de minéral osseux de rat où des cristaux d'apatite en forme de plaque, présentent une maille cristalline avec axe C malgré l'élimination de leur matrice fibreuse.
    Abstract: Zusammenfassung Es wird eine Methode beschrieben, wobei durch Anwendung von 95% Hydrazin ohne Wasserzugabe und mit nur geringem Erhitzen dem Knochen das gesamte Protein und ein kleiner Teil des Wassers entzogen wird. Diese Methode führte nur zu geringen chemischen Veränderungen und veränderte die strukturellen Eigenschaften der Mineralphase in keiner Weise. Physikochemische Daten wurden erbracht, welche zeigen, daß — obwohl die Kristalle von Rattenknochen den synthetischen Kontrollen (in Karbonat- und nicht hydroxydreichen Medien hergestellt) eher gleichen — Apatit aus Rattenknochen nicht auf sinnvolle Weise mittels bekannten oder postulierten Kristallmodellen interpretiert werden kann. CO 3 2− -Infrarotbandenzuteilungen, welche von Spektren aus dem Gesamtknochen gemacht wurden, geben wegen der Anwesenheit von Proteinabsorptionsbändern falsche Resultate. Die Absorption von HPO 4 2− wurde in den Infrarotspektren von Knochenmineral aus jungen Ratten beobachtet. Ein Vergleich der detaillierten Röntgendiffraktion von deproteinisiertem Rattenknochen vor und nach der Hydrolyse wies deutlich auf die Anwesenheit von amorphem Calciumphosphat hin. Die Elektronenmikroskopie zeigte kleine Apatitkristalle im Rattenknochen, welche zum Gesamtmineralpool beitragen könnten, der bei der Röntgendiffraktion amorph ist. Die Elektronenmikroskopie zeigte auch Gebiete im Rattenknochenmineral, wo plättchenartige Apatitkristalle eine deutlichec-Achsenorientierung beibehielten, obwohl ihre fibröse Matrix entfernt worden war.
    Notes: Abstract A method is described employing 95% hydrazine which completely deproteinates and slightly dehydrates bone under nearly anhydrous conditions with only moderate heating. This method induced only minor chemical changes and no alterations in structural properties of the mineral phase. Physicochemical data are presented demonstrating that although rat bone crystals more closely resemble synthetic controls made in carbonate-rather than hydroxide-rich media, rat bone apatite cannot be interpreted in terms of known or postulated crystal models in any meaningful fashion. CO 3 2− infrared band assignments made from spectra of whole bone are shown to be in error due to the presence of protein absorption bands. Absorotion of HPO 4 2− was observed in infrared spectra of young rat bone mineral. Detailed X-ray diffraction comparisons of deproteinated rat bone before and after hydrolysis clearly demonstrated the presence of amorphous calcium phosphate. Electron microscopy indicated that very small apatite crystals were present in rat bone which might also contribute to the overall mineral pool amorphous to X-ray diffraction. Electron microscopy also showed domains in rat bone mineral where plate-like apatite crystals maintained a netc-axis orientation despite the removal of their fibrous matrix.
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 13 (1973), S. 73-82 
    ISSN: 1432-0827
    Keywords: Bone ; Apatite ; Hydroxide ; Carbonate ; Infrared
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé L'étude de spectres infra-rouges montre que le minéral osseux de jeune rat et les apatites synthétiques, formés à des pH, force ionique et température physiologiques sont très déficients en ion OH; ces apatites biologiques et synthétiques présentent d'importants défauts internes de maille. En outre, une proportion significative des ions CO3 2- de mineral osseux de rat est structurée de façon lâche dans un environnement amorphe ou superficiel. Les ions carbonate dans l'os chauffé sous vide ou dans les apatites synthétiques formés à pH physiologique paraissent être situés dans des environnements locaux multiples. Le CO3 2- contenu dans ces structures peut se substituer dans des positions PO4 3- et (à un degré moindre) OH−, bien que des variations importantes de ou dans ces positions sont dues à des défauts de maille. Les carbonato-apatites, formés par transformation thermique (600o) de phosphates calciques amorphes et contenant 4–9% de CO3 2-, présentent surtout du CO3 2- dans des environnements OH−. Une recristallisation thermique des apatites biologiques et synthétiques, dans une atmosphère d'air, augmente le contenu en OH− et redispose les positions CO3 2-. Cependant, de telles formations bien cristallisées sont différentes des précurseurs apatitiques.
    Abstract: Zusammenfassung Die Infrarotspektroskopie ergab, daß sowohl natives Rattenknochenmineral als auch synthetische Apatite, welche bei physiologischem pH, Ionenstärke und Temperatur gebildet wurden, an Hydroxydionen stark defizient sind. Es ist ebenfalls ersichtlich, daß diese biologischen und synthetischen Apatitkristalle beträchtliche innere Verzerrungen aufweisen (Gitterdefekte). Weiterhin zeigt ein bedeutender Anteil der CO3 2--Ionen im Rattenknochenmineral eine lockere Struktur in amorpher Umgebung oder an der Oberfläche. In Vakuumerhitzem Knochen oder in synthetischen Apatit (mit physiologischem pH), welches in der Lösung gebildet wurde, scheinen sich die Carbonationen in verschiedenen Umgebungen zu finden. CO3 2- im Inneren dieser Stoffe kann in PO4 3--und (in viel kleineren Mengen) OH−-Positionen ausgetauscht werden, obwohl eine beträchtliche Abweichung von und innerhalb dieser Stellen wahrscheinlich auf Gitterdefekte zurückzuführen ist. Carbonat-Apatite, welche durch die thermische Umwandlung (600°C) von 4–9% CO3 2- enthaltendem amorphem Calciumphosphat gebildet wurden, zeigen in erster Linie in OH−-Umgebung CO3 2-. Die thermische Umkristallisierung von biologischen und synthetischen Apatiten in einer Luftatmosphäre erhöht den OH−-Gehalt und verteilt die CO3 2--Lokalisationen neu. Solche sehr schön kristallisierten Produkte spiegeln jedoch durchaus nicht ihre nativen Apatitvorbilder wider.
    Notes: Abstract Infrared spectral data indicate that both native rat bone mineral and synthetic apatites formed at physiological pH, ionic strength and temperature are extensively deficient in hydroxide ion content; the data also indicate that these biological and synthetic apatites contain considerable internal distortions (lattice defects). In addition, a significant portion of the CO3 2- ions in rat bone mineral is loosely-structured in either an amorphous or surface environment. Carbonate ions in vacuum-heated bone or solution-ripened synthetic (physiological pH) apatites appear to be in multiple local environments. Internal CO3 2- in these materials may be substituted in PO4 3- and (in much lesser amounts) OH− positions, although considerable deviation from or within these sites is probable due to lattice defects. Carbonateapatites produced by thermal conversion (600o) of amorphous calcium phosphates containing 4–9% CO3 2- exhibit CO3 2- mainly in OH− environments. Thermal recrystallization of biological and synthetic apatites in an air atmosphere increases OH− content and reorganizes CO3 2- locales. However, such extremely well-crystallized products are not at all representative of their native apatitic precursors.
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 33 (1981), S. 369-374 
    ISSN: 1432-0827
    Keywords: Histomorphometry ; Bone ; Reproducibility
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary To study bone histomorphometry reproducibility in normal subjects, we performed during orthopedic surgery bone biopsies in 16 post-menopausal women. Each woman had four bone biopsies, two at the usual site in the iliac crest, one on the left and one on the right side, and two other biopsies just behind the usual site, one at each side. We performed measurements of trabecular bone volume, relative osteoid volume, osteoid surfaces, osteoclastic resorption surfaces and calcification front. The average values of the 16 patients were compared, on the one hand, two by two, by a student test, and on the other hand, by a variance analysis. By these two methods the results showed no significant difference between the average values of the 16 patients at each location for any of the histomorphometric parameters studied. However, there was a location variation which was estimated by the intra-individual variation for a given patient. On the other hand, we calculated from the variance analysis the location variance for a group of 10 to 100 patients. In any case all the parameters had a location variation which was high for osteoclastic resorption surfaces and relative osteoid volume when expressed in % of the absolute value of these parameters. The variation of the trabecular bone volume was 0–46. 15% (95% confident limit interval) in a single patient and the hypothetical value of the location variation was 41.6% for a group of 10 patients and 13.0% for a group of 100 patients.
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 33 (1981), S. 35-39 
    ISSN: 1432-0827
    Keywords: Copper ; Resorption ; Bone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary An investigation of the role of copper in bone metabolism was undertaken. Explanted calvaria from 6-day-old mice were grown for 48 h in medium with and without the addition of copper sulfate. Active resorption was found to be significantly inhibited in the presence of copper sulfate concentrations of 10−6M and above. Copper sulfate concentrations of 10−5M and above inhibited hydroxyproline, protein, and DNA synthesis. Lower concentrations were ineffective. The effect of 5 × 10−6M copper sulfate on resorption was reversible. Several other compounds were tested for similar effects and at 5 × 10−6M were found to inhibit bone resorption in the order: copper sulfate 〉 brown gold chloride 〉 sodium aurothiomalate 〉 zinc sulfate 〉 sodium sulfate. The copper sulfate effect was twice that of sodium aurothiomalate, and sodium sulfate was not significantly inhibitory. The results suggest that the high serum copper levels associated with rheumatoid arthritis may reflect the activity of a hypothetical control mechanism of bone resorption. In the diseased state this would act to restore the normal rate of bone resorption.
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 12 (1973), S. 16-29 
    ISSN: 1432-0827
    Keywords: Bone ; Cartilage ; Culture ; Glycosaminoglycans ; Sephadex ; Collagen ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Des cultures de monocouches cellulaires d'épiphyses fémorales distales d'embryons de veaux sont étudiées immédiatement après la première sub-culture, réalisée après culture primaire. L'examen au microscope optique classique montre des dépôts disséminés de matériel métachromatique: en microscopie électronique, de fines fibrilles, considérées comme des fibres de collagène, en voie de développement, ont été observées. La nature des sécrétions cellulaires a été étudiée à l'aide de précurseurs radioactifs, fractionnés sur Sephadex G200, ainsi qu'à l'aide de chromatographie par échange d'ions. La digestion enzymatique par hyaluronidase et chondroitinase AC et ABC, bactérienne et testiculaire, démontre que les cellules synthétisent 70% de glycosaminoglycanes sulfatés et 30% de glycosaminoglycanes non sulfatés. Parmi les glycosaminoglycanes, 70% sont constitués par du chondroitine-4-sulfate, 20% par du chondroitine-6-sulfate et le reste probablement par du keratane-sulfate. Les études avec des acides aminés marqués indiquent que les cellules synthétisent une protéine de poids moléculaire élevé, contenant de l'hydroxyleproline, ainsi qu'une protéine non-collagénique, mise en évidence par incorporation de tryptophane.
    Abstract: Zusammenfassung Einschichtige Zellkulturen von der distalen Femurepiphyse von Kalbsembryonen wurden nach der ersten Subkultur untersucht, welche nach der Verschmelzung der primären Kulturen angesetzt wurde. Die lichtmikroskopische Untersuchung zeigte verstreute Ablagerungen von metachromatisch gefärbtem Material; bei der Elektronenmikroskopie wurden feine Fibrillen festgestellt, welche als Collagenvorstufe angesehen wurden. Nach einer Kultur von mehreren Tagen zeigte sich eine lacunäre Anordnung der Zellen. Die Beschaffenheit der Zellsekretionen wurde mittels radioaktiv markierten Verbindungen untersucht, welche auf Sephadex G200 und durch Ionenaustausch-Chromatographie fraktioniert wurden. Die enzymatische Verdauung mit bakterieller und testikulärer Hyaluronidase und Chondroitinase-AC und-ABC zeigte, daß die Zellen 70% sulfatierte und 30% nichtsulfatierte Glycosaminoglycane synthetisierten. Die sulfatierten Glycosaminoglycane enthielten 70% Chondroitin-4-Sulfat, 20% Chondroitin-6-Sulfat, und der Rest war wahrscheinlich Keratansulfat. Untersuchungen mit markierten Aminosäuren-Vorläufern deuteten darauf hin, daß die Zellen ein Hydroxyprolinhaltiges, hochmolekuläres Protein synthetisierten und dazu etwas Eiweiß, bei dem es sich auf Grund des Tryptophaneinbaues nicht um Collagen handeln kann.
    Notes: Abstract Monolayer cell cultures from the distal femoral epiphyses of embryo calves were studied following the first subculture, which was carried out after confluence in primary culture. Light microscopic examination revealed scattered deposits of metachromatic-staining material; on electron microscopy fine fibrils considered to be developmental collagen were seen. After several days in culture lacuna-like patterns of cells were seen. The nature of the cell secretions were studied by radioactive precursors, which were fractionated on Sephadex G200 and by ion exchange chromatography. Enzyme digestion with bacterial and testicular hyaluronidase and chondroitinase-AC and-ABC revealed that the cells synthesized 70% sulphated, and 30% non-sulphated glycosaminoglycans. Of the sulphated glycosaminoglycans 70% was chondroitin-4-sulphate, 20% chondroitin-6-sulphate, and the remainder probably keratansulphate. Studies were labelled amino acid precursors suggested that the cells synthesized a high-molecular weight protein containing hydroxyproline, as well as some non-collagenous protein, shown by tryptophan incorporation
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  • 6
    Electronic Resource
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    Springer
    Calcified tissue international 15 (1974), S. 173-179 
    ISSN: 1432-0827
    Keywords: Bone ; Strength ; Tension ; Compression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract A simple method is described for visualising regions of bone that have yielded in tension. The appearance of such regions is quite different from that of regions that have yielded in compression. The significance of these findings is discussed.
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 15 (1974), S. 189-199 
    ISSN: 1432-0827
    Keywords: Bone ; Densitometry ; X-ray ; Radiation ; Specific gravity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract X-ray and γ-radiation techniques for evaluating bone density under field conditions in cattle and sheep were investigated. The best results were obtained from measurements of the density of radiographs of tibial tarsal bones of sheep and from the absorption of γ-radiation of the tibial tarsal bones of sheep and the fibular tarsal bones of cattle. The γ-radiation techniques may be carried out rapidly under field conditions (up to 30 animals an hour) and bone density can be estimated with a standard error of 0.042–0.046 SG units.
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 13 (1973), S. 217-225 
    ISSN: 1432-0827
    Keywords: Fluoride ; Parathyroid ; Calcitonin ; Bone ; Calcium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé L'effet du fluor, de la parathormone et de la calcitonine sur le métabolisme du calcium osseux a été étudié en culture de tissu en utilisant des demi-calottes crâniennes de souris âgées de cinq jours. Les concentrations de fluor dans les cendres des calottes crâniennes de 0,007% (groupe peu fluoré), 0,041% (groupe moyennement fluoré) et 0,107% (groupe hautement fluoré) ont été obtenues en variant l'ingestion maternelle et post-natale en fluor. Le fluor inhibe la perte de calcium des os cultivés dans le milieu témoin et celui contenant la parathormone et favorise l'enrichissement en laccium des os cultivés dans un milieu contenant de la calcitonine. De l'os mort des groupes fortement et moyennement fluorés s'enrichit plus en calcium à partir du milieu de culture que les os du groupe pauvre en fluor. Le fluor semble agir sur le métabolisme du calcium osseux essentiellement par diminution de la solubilité minérale.
    Abstract: Zusammenfassung Der Einfluß von Fluorid, Parathormon und Calcitonin auf den Calciumstoffwechsel im Knochen wurde in einem Knochenkultur-System untersucht, wobei Halbcalvarien von 5 Tage alten Mäusen verwendet wurden. Fluoridgehalte in der Asche der Halbcalvarien von 0,007% (Gruppe mit niedrigem Fluoridgehalt), 0,041% (Gruppe mit mittlerem Fluoridgehalt) und 0,1075 (Gruppe mit hohem Fluoridgehalt) wurden erhalten, indem die Fluorideinnahme der Mütter oder der Neugeborenen verändert wurde. Fluorid hemmte den Calciumverlust aus Knochen, welche im Kontrollmedium oder in Parathormon-enthaltenden Medien kultiviert worden waren, und es förderte die Calciumaufnahme von Knochen, welche in Calcitoninenthaltendem Medium kultiviert worden waren. Die toten Knochen der Gruppen mit mittlerem und hohem Fluoridgehalt nehmen mehr Calcium aus dem Kulturmedium auf als die Knochen der Gruppe mit niederem Fluorid. Fluorid scheint vor allem durch eine Herabsetzung der Mineral-Löslichkeit auf den Calciumstoffwechsel der Knochen zu wirken.
    Notes: Abstract The influence of fluoride, parathyroid hormone and calcitonin on bone calcium metabolism was investigated in a bone culture system using half-calvaria of five-day old mice. Fluoride levels in the ash of half-calvaria of 0.007% (low fluoride group), 0.041% (moderate fluoride group), and 0.107% (high fluoride group) were achieved by varying the maternal and neonatal intake of fluoride. Fluoride inhibited the loss of calcium from bones cultured in control medium and parathyroid hormone-containing media, and promoted the uptake of calcium by bones cultured in medium containing calcitonin. Dead bones of the moderate and high fluoride groups took up more calcium from the culture medium than bones of the low fluoride group. Fluoride appears to exert its effect on bone calcium metabolism predominantly via a reduction in mineral solubility.
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  • 9
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    Electronic Resource
    Springer
    Calcified tissue international 31 (1980), S. 215-223 
    ISSN: 1432-0827
    Keywords: Bone ; 1,25(OH)2D3 ; 25OHD3 ; Histology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Rachitic rats, maintained on diets with low or normal P contents, were given daily intraperitoneal doses of 1,25(OH)2D3 or 25OHD3 at levels of 100 or 200 ng. Plasma chemistry was measured and the ash content and histological appearance of the bones investigated. Using labeled material it was shown that the dosing levels of 1,25(OH)2D3 employed ensured a higher than normal plasma concentration of that metabolite over the period between doses. 1,25(OH)2D3 was not as effective as 25OHD3 in raising bone ash or reducing the amount of osteoid. The difference between the effects of the metabolites was evident at both dietary P levels, but more marked at the higher P level. In contrast, the metabolites reduced the width of the epiphyseal plate to an approximately similar degree, and this is possibly the reason why there are discrepancies between previous reports of the effectiveness of 1,25(OH)2D3 compared with 25OHD3 or vitamin D3. Dosing with 1,25(OH)2D3 failed to maintain a constant plasma Pi value over the period between doses in animals fed the low P diet.
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  • 10
    ISSN: 1432-0827
    Keywords: Bone ; Osteosarcoma ; Matrix vesicles ; Alkaline phosphatase ; Aminopeptidase ; Naphthylamidase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Extracellular matrix vesicles from bovine fetal alveolar bone and from a dog osteosarcoma were isolated by differential centrifugation and then fractionated on a discontinuous sucrose density gradient. The fractions were examined by electron microscopy and were analyzed for protein, alkaline phosphatase, aminotripeptidase, and four different β-naphthylamidase activities. The low-density peak of enzyme activities was shown by electron microscopy to be much more homogeneous than the crude matrix vesicle fraction. Two major peaks of protein and enzyme activities were present, one in the high and one in the low density layers. There was good correlation between the activities of alkaline phosphatase and the various peptidases in the fractions from the sucrose density gradient. These results indicate a coexistence of peptidase and alkaline phosphatase in matrix vesicles. On the other hand, there was generally no correlation between the peptidase and alkaline phosphatase activities in vesicular specimens from bovine liver obtained in the same way. Most of the peptidase activity and about half of the alkaline phosphatase activity were solubilized from bone matrix vesicles by detergents. The extracted alkaline phosphatase and alanyl β-naphthylamidase activities were separated from each other on a DEAE-cellulose column.
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