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  • 1
    Electronic Resource
    Electronic Resource
    Effect of proteoglycans on in vitro hydroxyapatite formation (1979)
    Springer
    Calcified tissue international 27 (1979), S. 75-82 
    Details
    ISSN: 1432-0827
    Keywords: Proteoglycans ; Hydroxyapatite ; Amorphous calcium phosphate ; Nucleation ; Calcification
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Well-characterized bovine nasal proteoglycan A1 fraction (aggregate) and proteoglycan D1 fraction (subunit) have been shown to be effective inhibitors of hydroxyapatite (HA) formation in two in vitro test systems: (a) the transformation of amorphous calcium phosphate (ACP) to crystalline HA, and, (b) the direct precipitation of HA from low-concentration calcium phosphate solutions. A1 or D1 in solution slowed the transformation kinetics in system (a) without affecting the time to the onset of conversion. In system (b), A1 or D1 in solution increased the time to the onset of HA formation without affecting the HA formation kinetics. In both test systems A1 was a more effective inhibitor than D1, although the difference was not great. In both systems the inhibitory effect was proportional to the A1 or D1 solution concentration. The action of solutions of low and high molecular weight neutral dextrans on both test systems showed that high molecular weight and/or extended spatial molecular conformation has a much stronger correlation with inhibitory ability than solution viscosity. Proteoglycans have been implicated as playing a role in regulating biological mineralization particularly in the epiphyseal growth plate. Our study suggests that just enzymatic cleavage of aggregate into subunit is not sufficient to allow mineralization to occur, since we find that D1 itself is a potent inhibitor of HA formation. Further degradation and/or removal of D1 appears to be necessary for calcification to take place.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02441164
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  • 2
    Electronic Resource
    Electronic Resource
    The inhibitory effect of cartilage proteoglycans on hydroxyapatite growth (1984)
    Springer
    Calcified tissue international 36 (1984), S. 285-290 
    Details
    ISSN: 1432-0827
    Keywords: Proteoglycans ; Chondroitin 4-sulfate ; Neutral dextran ; Hydroxyapatite growth
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The calcification of connective tissues, including cartilage, is under the control of many interacting systems. Proteoglycans are thought to retard the deposition of hydroxyapatite crystals, and modification of the proteoglycans presumably facilitates mineralization in those tissues that are actively calcifying. The mechanism underlying these regulations remains speculative. This study investigates this question by comparing the inhibitory effectiveness of several macromolecules at neutral pH and approximately physiological ionic strengths. Inhibitors tested include bovine nasal proteoglycan monomer A1D1D1 and aggregate-containing A1 fractions, glycosaminoglycan chains (chondroitin 4-sulfate), and neutral dextran (as an uncharged analog). Hydroxyapatite growth was assessed either by measuring the time-dependent decreases in solution calcium and phosphate concentrations, or by determining utilization of hydroxyl ion in a pH-Stat. All species studied inhibit hydroxyapatite growth, and the extent of inhibition for each class is concentration-dependent. The proteoglycan aggregate-containing A1 fraction is more effective than the proteoglycan monomer at the same concentration, and the proteoglycan monomer is more effective than chondroitin 4-sulfate. Neutral dextran inhibits hydroxyapatite growth less effectively than proteoglycans. These results suggest that inhibition of hydroxyapatite growth by proteoglycans critically depends on both status (aggregate, monomer, etc.) and hydrodynamic size of this macromolecule, supporting the hypothesis that modification of proteoglycansin vivo functions to modulate the effectiveness of proteoglycans as a hydroxyapatite growth inhibitor.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02405332
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  • 3
    Electronic Resource
    Electronic Resource
    Oral contraceptive use and breast cancer risk among African-American women (1995)
    Springer
    Cancer causes & control 6 (1995), S. 321-331 
    Details
    ISSN: 1573-7225
    Keywords: Blacks ; breast carcinoma ; oral contraceptives ; United States
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Recent epidemiologic studies, most of them in predominantly White populations, have suggested that long duration of oral contraceptive (OC) use may increase the risk of breast cancer at young ages. We assessed the relationship of OC use to the risk of breast cancer in African-American women aged 25 to 59 years, using interview data from a multipurpose hospital-based case-control study. Five hundred and twenty-four cases hospitalized for invasive breast cancer were compared with 1,021 controls with nonmalignant conditions unrelated to OC use. Relative risks (RR) and 95 percent confidence intervals (CI) were estimated relative to a reference category of use for less than 12 months; potential confounders were controlled by multiple logistic regression analysis. Among women under age 45, three or more years of OC use was associated with an increased risk of breast cancer: the RR estimate was 2.8 (CI=1.5–5.0) for three to four years of use, and declined to 1.5 (CI=0.8.3.0) for 10 or more years of use. Recency and timing of use did not explain the observed association. Among women aged 45 to 59, OC use was associated with little or no increase in risk: the RR estimate for three or more years of use was 1.3 (CI=0.7–2.4). The findings add to the evidence from studies of White women and a recent study of Black women which have suggested an increased risk of breast cancer at young ages for moderate or long duration use of OCs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00051407
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  • 4
    Electronic Resource
    Electronic Resource
    Parental ages at birth in relation to a daughter's risk of breast cancer among female participants in the Framingham study (United States) (1995)
    Springer
    Cancer causes & control 6 (1995), S. 23-29 
    Details
    ISSN: 1573-7225
    Keywords: Breast neoplasms ; cohort study ; daughters ; maternal age ; paternal age ; United States
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Data from the Framingham Heart Study, collected in Framingham, MA (United States) during 1948–86, were used to evaluate the relation of parental age at birth to the risk of breast cancer among daughters. After 38 years of follow-up, 149 breast cancer cases occurred among 2,662 women. All but two cases were confirmed by histologic report. The rate of breast cancer increased among daughters with increasing maternal age at birth up to the mid-30s, where the rate levelled off. A similar pattern was observed with paternal age. After adjustment for other confouding factors and paternal age, the rate ratios for breast cancer in daughters whose mothers were aged 26 to 31 years and 32 or more years at their birth, relative to women whose mothers were aged 25 years or younger, were 1.5 (95 percent confidence interval [CI]=1.0–2.4) and 1.3 (CI=0.8–2.2), respectively. However, there was no longer an association between paternal age at birth and risk of breast cancer after controlling for maternal age and other risk factors.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00051677
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  • 5
    Electronic Resource
    Electronic Resource
    Transitional cell cancer of the urinary tract and renal cell cancer in relation to acetaminophen use (United States) (1998)
    Springer
    Cancer causes & control 9 (1998), S. 83-88 
    Details
    ISSN: 1573-7225
    Keywords: Acetaminophen ; kidney neoplasms ; renal cell carcinoma ; United States
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Experimental and epidemiologic evidence have suggested that phenacetin use increases the risk of transitional cell cancers of the urinary tract. The drug is no longer marketed but a commonly used metabolite, acetaminophen, has been linked recently to an increased risk of renal cancer. We assessed the relation of acetaminophen use to the risk of transitional cell cancer of the urinary tract and of renal cell cancer with data from a hospital-based study of cancers and medication use conducted from 1976-96 in the eastern United States. We compared 498 cases of transitional cell cancer and 383 cases of renal cell cancer with 8,149 noncancer controls and 6,499 cancer controls and controlled confounding factors with logistic regression. For transitional cell cancer, the relative risk (RR) estimate for regular acetaminophen use that had begun at least a year before admission was 1.1 (95 percent confidence interval [CI] = 0.6-1.9) based on noncancer controls, and 0.9 (CI = 0.5-1.6) based on cancer controls. RR estimates for use that lasted at least five years, and for nonregular use, were also close to 1.0. For renal cell cancer, the corresponding estimates were again close to 1.0. Our results suggest that acetaminophen, as used in present study population, does not influence the risk of transitional cell cancer of the urinary tract or of renal cell cancer.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008805505154
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  • 6
    Electronic Resource
    Electronic Resource
    Induced and spontaneous abortion in relation to risk of breast cancer (United States) (1997)
    Springer
    Cancer causes & control 8 (1997), S. 841-849 
    Details
    ISSN: 1573-7225
    Keywords: Abortion ; breast carcinoma ; risk factors ; United States ; women
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The relation of induced and spontaneous abortion to the risk of breast cancer is evaluated in a hospital-based case-control interview study conducted in three cities in the United States from 1985 through 1995. Cases were 1,803 women aged 25 to 64 years with newly diagnosed invasive breast cancer; controls were 4,182 women of the same ages admitted for conditions unrelated to reproductive factors. Other breast cancer risk-factors were controlled through multiple logistic regression. The reference for allanalyses was women who had never had an abortion, either induced or spontaneous. Among parous women, the relative risk (RR) estimate was 1.1 (95percent confidence interval [CI] = 0.9-1.5) for induced abortion overall, 1.0(CI = 0.7-1.4) for abortion before the first birth, and 1.3 (CI = 1.0-1.8)for abortion after at least one birth. Among nulliparous women, the relative risk estimate for induced abortion was 1.3 (CI = 0.9-1.9). There was no trend of increased risk with number of abortions, nor was there consistent evidence of an increased risk in any particular subgroup. Spontaneous abortion was not associated with increased risk of breast cancer, either among nulliparous women or among parous women. These findings provide little support for the hypothesis that induced abortion increases breast cancer risk overall or in particular subgroups.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1018408211089
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  • 7
    Electronic Resource
    Electronic Resource
    Über Küpenfarbstoffe (1909)
    Weinheim : Wiley-Blackwell
    Zeitschrift für die chemische Industrie 22 (1909), S. 2129-2131 
    Details
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/ange.19090224402
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  • 8
    Electronic Resource
    Electronic Resource
    Age-Related changes in cartilage proteoglycans: Quantitative electron microscopic studies (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Microscopy Research and Technique 28 (1994), S. 398-408 
    Details
    ISSN: 1059-910X
    Keywords: Aging ; Proteoglycans ; Electron microscopy ; Intervertebral disc ; Hyaline cartilage ; Nucleus pulposus ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Natural Sciences in General
    Notes: Biochemical and biophysical studies have shown that the composition and sedimentation velocity of cartilage proteoglycans change with age, but these investigations cannot demonstrate the alterations in molecular structure responsible for these changes. Development of quantitative electron microscopic methods has made it possible to define the age-related structural changes in aggregating proteoglycans and to correlate the alterations in their structure with changes in tissue composition and morphology. Electron microscopic measurement of human and animal hyaline cartilage proteoglycans has shown that with increasing age the length of the chondroitin sulfate-rich region of aggregating proteoglycan monomers (aggrecan molecules) decreases, the variability in aggrecan length increases, the density of aggrecan keratan sulfate chains increases, the number of monomers per aggregate decreases, and the proportion of monomers that aggregate declines. Proteoglycans from the nucleus pulposus of the intervertebral disc show similar but more dramatic age-related alterations. At birth, nucleus pulposus aggrecan molecules are smaller and more variable in length than those found in articular cartilage. Within the first year of human life, the populations of aggregates and large aggrecan molecules analogous to those found in articular cartilage decline until few if any of these molecules remain in the central disc tissues of skeletally mature individuals. The mechanisms of the age-related changes in cartilage proteoglycans have not been fully explained, but measurement of proteoglycans synthesized by chondrocytes of different ages suggests that alterations in synthesis produce at least some of the age-related changes in aggrecan molecules. Degradation of aggrecan chondroitin sulfate-rich regions in the matrix probably also contributes to the structural changes seen by electron microscopy. Age-related changes in proteoglycan aggregation may be due to alterations in link protein function or inhibition of aggregation of newly synthesized aggrecan molecules by accumulation of degraded aggrecan molecules. © 1994 Wiley-Liss, Inc.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jemt.1070280506
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  • 9
    Electronic Resource
    Electronic Resource
    Carbene in räumlich begrenzten Systemen I. 1,3-C-H-Insertionsreaktion von Adamantyliden im β-Cyclodextrin-HohlraumCarbene Rearrangements, 41. Mitteilung. Wir danken der American Maize-Products Company, Hammond, IN, für die in dieser Untersuchung verwendeten Cyclodextrine. - 40. Mitteilung: L.Xu, G. Lin, F. Tao, U. H. Brinker, Acta Chem. Scand. 1992, 46, 650.Professor Emanuel Vogel zum 65. Geburtstag gewidmet. (1993)
    Weinheim : Wiley-Blackwell
    Zeitschrift für die chemische Industrie 105 (1993), S. 1427-1429 
    Details
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/ange.19931050943
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  • 10
    Electronic Resource
    Electronic Resource
    Neuerungen auf dem Thioindigorot-gebiet (1908)
    Weinheim : Wiley-Blackwell
    Zeitschrift für die chemische Industrie 21 (1908), S. 961-970 
    Details
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/ange.19080212002
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