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  • 1
    Publication Date: 1998-02-01
    Print ISSN: 1420-682X
    Electronic ISSN: 1420-9071
    Topics: Biology , Medicine
    Published by Springer
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  • 2
    Publication Date: 1978-04-18
    Print ISSN: 0006-2960
    Electronic ISSN: 1520-4995
    Topics: Biology , Chemistry and Pharmacology
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  • 3
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Biochemistry 17 (1978), S. 1431-1436 
    ISSN: 1520-4995
    Source: ACS Legacy Archives
    Topics: Biology , Chemistry and Pharmacology
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 54 (1994), S. 414-420 
    ISSN: 1432-0827
    Keywords: Fourier transform Raman spectroscopy ; Calcium phosphate ; Hydroxyapatite ; Octacalcium phosphate ; Matrix vesicles
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract Fourier-transform (FT) Raman spectroscopy was used to characterize the organic and mineral components of biological and synthetic calcium phosphate minerals. Raman spectroscopy provides information on biological minerals that is complimentary to more widely used infrared methodologies as some infrared-inactive vibrational modes are Raman-active. The application of FT-Raman technology has, for the first time, enabled the problems of high sample fluorescence and low signal-to-noise that are inherent in calcified tissues to be overcome. Raman spectra of calcium phosphates are dominated by a very strong band near 960 cm−1 that arises from the symmetric stretching mode $$\left( {{\mathbf{\rlap{--} v}}_{\text{1}} } \right)$$ of the phosphate group. Other Raman-active phosphate vibrational bands are seen at approximately 1075 $$\left( {{\mathbf{\rlap{--} v}}_{\text{3}} } \right)$$ , 590 $$\left( {{\mathbf{\rlap{--} v}}_{\text{4}} } \right)$$ , and 435 cm−1 $$\left( {{\mathbf{\rlap{--} v}}_{\text{2}} } \right)$$ . Minerals containing acidic phosphate groups show additional vibrational modes. The different calcium phosphate mineral phases can be distinguished from one another by the relative positions and shapes of these bands in the Raman spectra. FT-Raman spectra of nascent, nonmineralized matrix vesicles (MV) show a distinct absence of the phosphate $${\mathbf{\rlap{--} v}}_{\text{1}}$$ band even though these structures are rich in calcium and phosphate. Similar results were seen with milk casein and synthetic Ca-phosphatidyl-serine-PO4 complexes. Hence, the phosphate and/or acidic phosphate ions in these noncrystalline biological calcium phosphates is in a molecular environment that differs from that in synthetic amorphous calcium phosphate. In MV, the first distinct mineral phase to form contained acidic phosphate bands similar to those seen in octacalcium phosphate. The mineral phase present in fully mineralized MV was much more apatitic, resembling that found in bones and teeth. These findings are consistent with formation of an OCP-like precursor during MV mineral formation that subsequently hydrolyzes to form hydroxyapatite.
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  • 5
    ISSN: 1432-0827
    Keywords: Bone ; Epiphyses ; Calcification ; Physiologic ; Phospholipids ; Phosphorus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Neuf polets, âgés de huit semaines, ont reçu 1 mCi de32P orthophosphate par voi intrapéritonéale. Ils ont été sacrifiés 2, 14, 38, 86 et 169 heures asprès injection. Les épiphyses des os longs ont été prélevées et séparés en cartilage au repos, cartilage en voie de prolifération, cartilage en voie de calcification et os spongieux primitif. Les lipides sont extraits: chaque tissu est déminéralisé et les lipides sont extraits à nouveau. On détermine ainsi le contenu en lipides totaux et en phospholipides, ainsi que leurs divers types et l'activité spécifique relative: Le contenu lipidique total de tous les tissus épiphysaires est de 1,35 à 4,52% en poids sec de matrice déminéralisée. La fraction phospholipipidique constitue environ la moitié des lipides. Dans les régions à contenu élevé en calcium, plus de phospholipides sont extraits après déminéralisation qu'avant. Des phospholipides neutres constituten 80–90% des phospholipides totaux dans les extraits réalisés avant déminéralisation, et seulement 48–65% dans les extraits après déminéralisation. La quantité des phospholipides, éthanolamine et sérine, est variable dans les diverses zone épiphysaires. La quantité et les types de phospholipides et leur rapport avec le degré de calcification concordent avec les résultats publiés pour les tissus de veaux. Les courbes d'activité spécifique démontrent une activité réduite au niveau de cartilage au repos et des échange très actifs en phospholipides dans les trois autres zones épiphysaires. Les divers types de phospholipides ont des activités métaboliques nettement différentes les uns par rapport aux autres. Les modes d'échanges particuliers de la phosphatidyle ethanolamine, de la phosphatidyle sérine et de la phosphatidyle inositol, au niveau du cartilage en voie de prolifération et de calcification, suggérent un rôle spécial de ces lipides dans le mécanisme de las croissance et de la calcification.
    Abstract: Zusammenfassung Neun achtwöchige Hühner erhielten intraperitoneal 1 mCi32P-Orthophosphat und wurden 2, 14, 38, 86 und 169 Std nach der Injektion getötet. Die Epiphysen der Röhrenknochen wurden seziert und ruhende, proliferierende und verkalkende Knorpel, sowie primäre Spongiosa voneinander getrennt. Die Lipide jeder Zone wurden extrahiert, jedes Gewebe wurde demineralisiert und die Lipide erneut extrahiert. Der Gehalt der Extrakte an Gesamtlipden und Phospholipiden sowie die Art der Phospholipide wurden bestimmt und die relative spezifische Aktivität: gemessen. Der Gehalt an Gesamtlipiden aller epiphysischen Gewebe betrug 1,35–4,52% des Trockengewichtes der demineralisierten Matrix. Phospholipide machten ungefähr die Hälfte der Gesamtlipide aus. In den Zonen mit hohem Calciumgehalt konnten mehr Phospholipide nach der Demineralisation als vorher extrahiert werden. Die neutralen Phospholipide entsprachen in vor der Demineralisation erhaltenen Extrakten 80–90% und in jenen nach der Demineralisation nur 48–65% der gesamten Phospholipide. Die Aethanolamin- und Serinphospholipidmengen variierten bedeutend in den verschiedenen Zonen der Epiphyse. Die Menge und die Art der Phospholipide und ihr Verhältnis in bezug auf Verkalkungsgrad waren in Einklang mit den Werten, die für das Kalb angegeben werden. Die Kurven der relativen spezifischen Aktivität zeigten ein träges metabolisches Muster im ruhenden Knorpel und einen sehr aktiven Phospholipidumsatz in den drei anderen Zonen der Epiphyse. Die verschieden gearteten Phospholipide zeigten untereinander merklich verschiedene metabolische Muster. Die speziellen Eigenschaften der Umsatzsmuster von Phosphatidyläthanolamin, Phosphatidylserin und Phosphatidylinositol in proliferierendem und verkalkendem Knorpel lassen vermuten, daß diese Lipide spezielle Funktionen im Wachstums- oder Verkalkungsprozeß ausüben.
    Notes: Abstract Nine eight-week old chicks were given32P orthophosphate, 1 mCi, intraperitoneally and killed 2, 14, 38, 86, and 169 hours after injection. Long bone epiphyses were dissected and separated into resting cartilage, proliferating cartilage, calcifying cartilages, and primary spongiosa. Lipids were extracted from each zone, each tissue was demineralized, and lipids were extracted again. The extracts were analyzed for total lipid and phospholipid content, types of phospholipids, and relative specific activity. Total lipid content of all epiphyseal tissues was 1.35 to 4.52% of the dry demineralized matrix weight. Phospholipid was about half the total. In the zones with higher calcium content more phospholipid was extracted after demineralization that before. Neutral phospholipids were 80 to 90% of the total phospholipids in predemineralization extracts and only 48 to 65% in extracts after demineralization. The amount of ethanolamine and serine phospholipids varied considerably in different epiphyseal zones. The amount and types of phospholipid and their relation to degree of calcification corroborated data reported for the calf. Relative specific activity curves revealed a sluggish metabolic pattern in resting cartilage and very active phospholipid turnover in the other three epiphyseal zones. The different types of phospholipids had markedly different metabolic patterns from each other. Special features of the turnover patterns of phosphatidyl ethanolamine, phosphatidyl serine, and phosphatidyl inositol in proliferating and calcifying cartilage suggest special roles of these lipids in the growth or calcification process.
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 8 (1971), S. 24-35 
    ISSN: 1432-0827
    Keywords: Bone ; Cartilage ; Epiphysis ; Calcium ; Phosphorus ; Vitamin D
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Les électrolytes ont été analysés dans le sérum et dans les tissues en voie de minéralisation, à des stades variables de calcification, chez des poulets et des pores normaux et rachitiques. L'humidité, les cendres et les matières organiques et déssèchées ont été analysées. Il apparait que d'autres électrolytes sériques, en plus du Ca, sont modifiés au cours du rachitisme. Le Mg et le P inorganique sont modifiés de façon variable au cours de l'avitaminose D. Des changements plus importants en contenu minéral des tissus sont observés dans les stades précoces de calcification que ceux que l'on a pu constater dans le sérum à des stades similaires, ce qui suggère un effet direct de l'avitaminose sur le tissu en voie de calcification. Quant au contenu du sérum, le dépôt de Ca est plus élevé dans les tissus d'animaux rachitiques par rapport aux témoins. Ceci n'est pourtant pas le cas du Mg ou du P inorganique, indiquant une affinité préférentielle du Ca pour le tissue rachitique. L'analyse gravimétrique de matières organiques et déssèchées des zones épiphysaires montre que les quantités de cartilage hypertrophique et en voie de dévelopment augmentent dans le cas de rachitisme, alors que le cartilage calcifié diminue, confirmant les observations histologiques antérieures. De manière inattendue, la proportion de cartilage au repos augmente au cours du rachitisme.
    Abstract: Zusammenfassung Die Elektrolyte im Serum und in mineralisierenden Geweben wurden zu verschiedenen Zeitpunkten der Verkalkung bei normalen Hühnern und Schweinen und bei solchen mit Vitamin D-Mangel analysiert. Wassergehalt, Asche, trockene und organische Substanz wurden ebenfalls gemessen. Die Ergebnisse zeigten, daß außer Ca auch andere Elektrolyte bei Rachitis verändert wurden. Mg und anorganischer P wurden durch den Vitaminmangel bei den beiden Gattungen verschiedenartig beeinflußt. In den Geweben wurde in den frühen Phasen der Verkalkung eine größere Änderung des Mineral-Spiegels gefunden, als dies zu übereinstimmenden Zeiten im Serum der Fall war, was auf eine direkte Wirkung des Vitaminmangels auf das verkalkende Gewebe schließen läßt. Im Verhältnis zum Serumspiegel wurde Ca in den Geweben der rachitischen Tiere zu einem größeren Grade als normal abgeschieden. Dies war nicht der Fall bei Mg oder anorganischem P, was einen Vorzug für Ca in den rachitischen Geweben anzeigt. Gravimetrische Analysen von organischer und trockener Substanz in epiphysischen Schichten zeigten, daß die Menge des proliferierenden und hypertrophischen Knorpels zunahm und daß verkalkter Knorpel bei Rachitis abnahm, gemäß klassischen histologischen Beobachtungen. achtungen. Ganz unerwartet war bei Rachitis eine verhältnismäßige Zunahme des ruhenden Knorpels festzustellen.
    Notes: Abstract Electrolytes were analyzed in serum, and in mineralizing tissues at varying stages of calcification, in normal and vitamin D-deficient chickens and pigs. Moisture, ash, and organic matter were also measured. Results revealed that in addition to Ca, other serum electrolytes were altered in rickets. Mg and inorganic P were diversely affected by the vitamin deficiency. Larger changes in mineral level were seen in the tissues in the early stages of calcification than were seen at corresponding times in the serum, suggesting a direct effect of the vitamin deficiency on the calcifying tissue itself. Relative to the serum level, Ca was deposited in the tissues of rachitic animals to a greater extent than in normal animals. This was not true for Mg or inorganic P, indicating a preferential affinity for Ca in the rachitic tissue. Gravimetric analyses of organic and dry matter in epiphyseal zones revealed that the amounts of proliferating and hypertrophic cartilage were increased, and calcified cartilage decreased, in rickets, in accord with previous histological observations. Unexpectedly, the proportion of resting cartilage was also increased.
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 8 (1971), S. 36-53 
    ISSN: 1432-0827
    Keywords: Phospholipids ; Vitamin D ; Deficiency ; Epiphysis ; Cartilage ; Bone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Les effets de divers degrés de rachitisme non compliqué, provoqué par avitaminose D, sur les concentrations, la composition, et l'extractibilité de phospholipides de tissus moux et en voie de calcification ont été étudiés chez le poulet et le porc. Le contenu en phospholipides des tissus en voie de calcification est modifié au cours du rachitisme; cependant, on n'a constaté que peu de changements dans les tissus moux. Les effets quantitatifs sur la concentration en lipides des tissus rachitiques calcifiés varient de zone en zone et semblent indiquer desvariations dans d'autres constituants tissulaires. Cependant les différences qualitatives indiquent un effet direct sur des phospholipides spécifiques. Les phospholipides acides présentent les changements de pourcentage les plus élevés bien que de nombreuses modifications statisstiquement significatives dans les phospholipides neutres ont pu être observés. Les zones stisulaires présentant le plus grand changement de composition phospholipidique au cours du rachitisme, sont constituées par le cartilage hypertrophique et en voie de prolifération et par l'os spongieux, alors que le cartilage calcifié est le moins affecté. Le rachitisme diminue aussi l'extractibilité de certains phospholipides neutres et acides des zones de minéralisation précoce. Ces résultats semblent indiquer la présence, dans le tissu rachitique, de concentrations élevées de phospholipide complexé avec le phosphate de calcium, probablement causé par l'inhibition de la minéralisation normale.
    Abstract: Zusammenfassung Die Auswirkung von verschiedenen Graden von Rachitis (verursacht durch Vitamin D-Mangel) auf die Mengen, die Zusammensetzung und auf die Extrahierbarkeit der Phospholipide von verkalkenden und weichen Geweben wurde an Hühnern und Schweinen untersucht. Es wurden verschiedene Wirkungen von Rachitis auf die Phospholipid-Zusammensetzung der verkalkenden Gewebe gefunden, in den weichen Geweben jedoch nur wenige. Der Grad dieser Wirkung auf die Lipid-Konzentration der rachitisch verknöchernden Gewebe änderte sich von Schicht zu Schicht und schien die Änderungen in anderen Gewebebestandteilen wiederzugeben. Die qualitativen Unterschiede zeigten jedoch eine direkte Wirkung auf spezifische Phospholipide an. Saure Phospholipide zeigten den größten prozentualen Unterschied, obgleich zahlreiche statistisch signifikante Unterschiede auch in den neutralen Phospholipiden gefunden wurden. Die Gewebeschichten, welche bei Rachitis die größte Änderung in der Phospholipidzusammensetzung zeigten, waren proliferierender und hypertrophischer Knorpel und spongiöser Knochen, während verkalkter Knorpel die geringste Änderung zeigte. Rachitis verminderte auch die Extrahierbarkeit von gewissen sauren und neutralen Phospholipiden aus den Schichten der frühen Mineralisierung. Diese Ergebnisse weisen auf das Vorhandensein von erhöhten Phospholipidmengen im rachitischen Gewebe hin, welche Calciumphosphat binden; dies wird wahrscheinlich durch die Blockierung der normalen Mineralisierung verursacht.
    Notes: Abstract The effect of various degrees of simple, vitamin D-deficient rickets on the levels, composition and extractability of phospholipids from calcifying and soft tissues was studied in chickens and pigs. A variety of effects of rickets on the phospholipid composition of the calcifying tissues were detected; there was little change in the soft tissues. The quantitative effects on the lipid concentration of rachitic hard tissues were variable from zone to zone and appeared to reflect variations in other tissue constituents. However, the qualitative differences indicated a direct effect on specific phospholipids. Acidic phospholipids displayed the greatest percentage change, although numerous statistically-significant changes were also seen in the neutral phospholipids. Tissue zones displaying the greatest change in phospholipid composition in rickets were proliferating and hypertrophic cartilage, and cancellous bone, with calcified cartilage showing the least effect. Rickets also reduced the extractability of certain acidic and neutral phospholipids from zones of early mineralization. These findings are interpreted as indicating the presence of elevated levels of phospholipid complexed with calcium phosphate in rachitic tissue, presumably due to the blockage of normal mineralization.
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 62 (1998), S. 341-349 
    ISSN: 1432-0827
    Keywords: Key words: Cadmium — Zinc — Manganese — Cell culture — Mineralization.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract. The effects of the trace metals zinc (Zn), manganese (Mn), and cadmium (Cd) on the metabolism of growth plate chondrocytes was examined using a mineralizing culture system. Supplementation of serum-free primary cultures of growth plate chondrocytes with 10–100 μm Zn resulted in an increase in cell protein and greatly increased alkaline phosphatase (AP) activity; however, above 25 μm Zn mineralization of the cultures was reduced. The effects of Zn on cellular protein and AP activity were enhanced by the addition of the albumin to the culture media. Removal of Zn from basal culture media resulted in recoverable reductions in cellular protein and AP activities. Cadmium was acutely toxic to chondrocyte cell cultures at concentrations above 5 μm. Even at very low concentrations (0.25 μm) Cd caused significant reductions in DNA, cellular protein, and matrix protein synthesis. In contrast, Cd had negligible effects on AP activity or culture mineralization. Manganese treatment (50 μm) resulted in reduced levels of proteoglycan, cell protein, DNA synthesis, and collagen synthesis, although AP specific activity did not change. At 10 μm, Mn significantly reduced mineralization but had only minor influence on other culture parameters. Both Zn (200 μm) and Cd (0.1 μm), but not Mn, induced the synthesis of metallothionein. The physiological and biochemical effects of specific metal ions is largely dependent on their physicochemical properties, especially their ligand affinities. Knowledge of these properties allows predictions to be made regarding whether the organic or the mineral phase are most likely to be affected in a mineralized tissue.
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 23 (1977), S. 135-139 
    ISSN: 1432-0827
    Keywords: Matrix vesicles ; Epiphyseal cartilage ; Phospholipid metabolism ; Chondrocytes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The in vivo metabolism of32P orthophosphate into phospholipids of chondrocyte, matrix vesicle, and membrane fractions of chicken epiphyseal cartilage has been studied. Incorporation of radioactive phosphate into the total phospholipid fraction of matrix vesicles was rapid, the labeling of phosphatidylcholine and lysophosphatidylserine being even more rapid in matrix vesicles than in chondrocytes. These findings indicate that matrix vesicles are formed by a rapid, metabolically active process, and are not remmants of dead cells, as had previously been postulated by some workers. The rate of incorporation of32P orthophosphate into phosphatidylserine and sphingomyelin of matrix vesicles was significantly slower than that of phosphatidylcholine and certain other vesicle phospholipids. These findings are paradoxical because, compared with chondrocytes, matrix vesicles were enriched in phosphatidylserine and sphingomyelin and depleted in phosphatidylcholine. These results indicate that in vesicle formation the rates of degradation of the various phospholipid classes must be markedly different: phosphatidylcholine must be degraded much more rapidly than either phosphatidylserine or sphingomyelin. Support for this comes from previous data which revealed that substantial phospholipase activity is present in epiphyseal cartilage, especially in the zone of hypertrophy where matrix vesicle formation appears to be particularly active.
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 23 (1977), S. 125-133 
    ISSN: 1432-0827
    Keywords: Electrolytes ; Calcium phosphate ; Matrix vesicles ; Chondrocytes ; Epiphyseal cartilage
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Chondrocyte, matrix vesicle, and membrane fractions, as well as interstitial fluid samples from the proliferating and hypertrophic zones of chicken epiphyseal cartilage were analyzed for electrolyte content. Intracellular Ca levels were 1.4–2.1 mM, over 90% of which was nondiffusible. Isolated hypertrophic chondrocytes had higher intracellular Na and lower K than proliferating cells. Matrix vesicles contained 25 to 50 times higher concentrations of Ca than the adjacent cells. Vesicles from the zone of hypertrophy contained twice as much Ca as did those from the proliferating area. Ca/P1 molar ratios of matrix vesicles were much higher than those of cells or of later mineral deposits. These findings indicate that Ca is concentrated in matrix vesicles during formation, but acuumulation of Ca and P1 must continue in the matrix. X-ray diffraction of freeze-dried vesicle and membrane fractions failed to detect crystalline apatite, suggesting that crystals seen in electron micrographs of matrix vesicles may be artifacts. Interstitial fluid expressed from epiphyseal cartilage was higher in K, Pi, Mg and nucleotides, and lower in Na and Cl, than blood plasma. Fluid from the hypertrophic zone was higher in K and nucleotides, but not Pi or Mg, than that from the proliferating layer. These data suggest that selective leakage or extrusion of these constituents, which are normally intracellular, must occur, especially in the hypertrophic zone. More of the Ca and Mg, and less of the Pi, was protein-bound in cartilage fluid than in blood plasma. There was more binding of the divalent cations in fluid from proliferating than from hypertrophic cartilage. The presence of greater amounts of ultrafilterable peptides in fluid from hypertrophic than from proliferating cartilage or blood plasma, suggests that proteolytic activity may release bound divalent cations during mineralization.
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