ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Organic Chemistry  (62)
  • Cell & Developmental Biology  (9)
  • 1
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: We studied the expression of osteoblastic markers in cultured cells isolated from the bone of 15 patients with different clinical forms of osteogenesis imperfecta (OI) and of seven fetal and postnatal controls. Cultured bone cells of ten OI patients produced abnormal collagen type I. Similar to controls, OI bone cells produced predominantly collagen type I with traces of collagen types III and V. The 1,25(OH)2 vitamin D3-stimulated synthesis of osteocalcin, a specific osteoblastic marker protein, was similar in OI bone cells and age-matched controls. Bone cells from fetal controls and from patients with the perinatal lethal OI type II produced less osteocalcin than bone cells from postnatal controls and surviving OI patients. OI bone cells responded to parath.yroid hormone (PTH) by increased production of cAMP similar to controls. Bone cells from fetal controls and from OI type II donors showed a decreased response to PTH. Activity of the bone-liver-kidney isoenzyme alkaline phosphatase (AP) was detected in all control and OI bone cells. The expression of all osteoblastic markers was similar in bone cells producing abnormal collagen type I. These observations show that OI bone cells in vitro express a pattern of osteoblastic markers similar to age-matched control bone cells indicating that osteoblastic differentiation is not altered by the underlying defects of collagen type I metabolism in OI bone cells. © 1993 Wiley-Liss, Inc.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 159 (1994), S. 423-433 
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Using the Madin Darby canine kidney (MDCK) cell “calcium switch,” we have previously demonstrated that, as MDCK cells establish contact and ultimately form tight junctions, there are marked global and localized changes in intracellular calcium at the sites of cell-cell contact (Nigam et al., 1992, Proc. Natl. Acad. Sci. USA, 89:6162-6166). We have now examined whether intracellular Ca++ is critical to the biogenesis of tight junctions by chelating this ion and monitoring the formation of junctions by electrical, immunocytochemical, and biochemical criteria. Intracellular Ca++ was chelated with the cell-permeant chelators, dimethyl-BAPTA-AM and BAPTA-AM. By digital imaging of fura-2 loaded cells, it was demonstrated that both agents efficiently chelated Ca++ during the “switch” in a dose-dependent manner which paralleled their respective in vitro affinities for Ca++. Chelation of Ca++ during the switch markedly attenuated the development of transepithelial electrical resistance (TER), a measure of tight junction assembly. Immunofluorescent staining of the tight junctional protein, zonula occludens-1 (ZO-1), revealed that chelation of intracellular Ca++ retarded the movement of ZO-1 from intracellular sites to the plasma membrane during the switch. During the development of tight junctions, a fraction of ZO-1 redistributed from the Triton X-100 soluble to the Triton X-100 insoluble pool; chelation of Ca++ during the induction of cell-cell contact prevented this stabilization into the Triton X-100 insoluble fraction. Taken together, these data indicate an important role for intracellular Ca++ in tight junction biogenesis and suggest a specific role for calcium in the early sorting and possible cytoskeletal association of tight junction components. © 1994 wiley-Liss, Inc.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    BioEssays 18 (1996), S. 1039-1042 
    ISSN: 0265-9247
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Dr Sydney Brenner has played a major, and unique, role in biology during the past 40 years. His contributions have ranged from key work on the structure of the genetic code and the existence of mRNA through the development of Caenorhabditis elegans as a key model system in developmental biology to genomic analysis and function in vertebrates. BioEssays went to interview Dr Brenner at his home in the cathedral city of Ely, England, on the significance of the genome projects for human biology, in particular, and for biology, in general.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Applied Organometallic Chemistry 6 (1992), S. 463-478 
    ISSN: 0268-2605
    Keywords: Hydrotreatment ; hydrodesulfurization ; hydrodenitrogenation ; molybdenum ; clusters ; thiophene ; pyridine ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Sulfide cluster-derived ensembles are promising models of the active sites in commercial hydrotreatment catalysts. A series of sulfide clusters were adsorbed intact onto high-surface-area γ-alumina, magnesium oxide and activated carbon supports, then pretreated to produce highly dispersed catalytic ensembles with sizes similar to those of their precursor clusters. The activities of the bimetallic cluster-derived catalysts were significantly higher than those of the monometallic catalysts. We took this as evidence that direct interactions between molybdenum and the promoter element cause the promotional effect observed in commercial hydrotreatment catalysts. The hydrodesulfurization and hydrodenitrogenation activities correlated with the extent of molybdenum reduction. Our results suggested that the active sites in promoted hydrotreatment catalysts are centered on molecular-scale ensembles containing molybdenum, sulfur and the promoter element.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1975 (1975), S. 660-671 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses with Cyclic Mono-or Dialkynes and Butadiene; Ring Expansion by 4, 8, and 16 C-AtomsCyclic mono- and dialkynes can be co-oligomerized with two or four molecules of butadiene to di- and tricyclic cis-1,cis-4,trans-7-cyclodecatriene derivatives. Cyclododecyne, 1,8-cyclotetradecadiyne, and 5-oxa-1,8-cyclotetradecadiyne have been subjected to such reaction. Partial hydrogenation of the ten-membered rings formed and their oxidative cleavage to di- and tetraketones lead to a ring enlargement by 8 or 16 carbon atoms. It is shown using as example the cyclodecatriene derivative formed from cyclododecyne and two molecules of butadiene, that the same reactions lead (after thermal rearrangement of the ten-membered rings to the correspondending cis-4,5-divinylcyclohexenes) to a ring enlargement by 4 C-atoms and simultaneous introduction of two ethyl groups.
    Notes: An Nickel-Ligand-Katalysatoren lassen sich cyclische Mono- und Dialkine mit zwei oder vier Molekülen Butadien zu di- bzw. tricyclischen cis-1, cis-4, trans-7-Cyclodecatrienderivaten verknüpfen. Als Alkine wurden Cyclododecin, 1,8-Cyclotetradecadiin und 5-Oxa-1,8-cyclotetradecadiin eingesetzt. Partielle Hydrierung der gebildeten Zehnringe und deren oxidative Spaltung zu Di- oder Tetraketonen führt zu einer Ringerweiterung um 8 bzw. 16 C-Atome. Am Beispiel des Cyclodecatrienderivates aus Cyclododecin und zwei Molekülen Butadien wird gezeigt, daß die gleichen Reaktionen nach thermischer Umlagerung der Zehnringe in die entsprechenden cis-4,5-Divinylcyclohexene zu einer Ringerweiterung um 4 C-Atome und gleichzeitiger Einführung einer Diäthylgruppierung führen.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Philadelphia : Wiley-Blackwell
    Journal of Cellular and Comparative Physiology 64 (1964), S. 43-49 
    ISSN: 0095-9898
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    New York, N.Y. : Wiley-Blackwell
    Journal of Cellular Biochemistry 53 (1993), S. 234-241 
    ISSN: 0730-2312
    Keywords: Breast cancer risk ; chemoprevention ; intermediate biomarkers ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Early phase chemoprevention trials differ from standard therapeutic clinical trials because asymptomatic, healthy people are treated with a potentially toxic intervention for a prolonged period of time. Current subject selection protocols have relied upon epidemiological methods to identify highrisk individuals. Most available data provide risk estimates for various individual risk factors, but few have reported risk estimates for combinations of risk factors. Selection criteria for the large tamoxifen intervention trial (NSABP P1) were developed from the work of Gail et al. [1]. The Gail model takes into account non-genetic factors (e.g., nulliparity, age at menarche, preexisting pathological conditions) and genetic factors (family history). Using a lifetime risk of 10% of developing breast cancer as a standard to intervention trial. This approach has been criticized for being insufficiently selective (i.e., all women ≥60 yrs), but appears to be the best available method to select subjects for a chemoprevention trial. Other approaches have been based on identification of very high-risk women with acknowledged pathologic conditions [lobular carcinoma in situ, ductal carcinoma in situ (DCIS)]. Attempting to use these proliferative lesions as pathologic endpoints for drug effect has not been attempted. DCIS as a risk factor for tamoxifen intervention was excluded because of controversies over its management and because of frequent difficulties in distinguishing microinvasive from non-invasive lesions. Women treated for early stage breast cancer (Stage I) may be subjects for early stage chemopreventive interventions.We propose the use of intermediate endpoint biomarkers and genetic markers as entry criteria for early phase chemoprevention trials. For colorectal cancer chemoprevention, we have used a two-step selection process. The first step was based on epidemiologic risk assessment. Entry into the study required that a potential intermediate biomarker be positive and quantifiable. The relationship between modulation of a pre-transformational biomarker and development of cancer ultimately needs proof in a primary interventional trial; however, this methodology may permit screening of potential chemopreventive agents at lower cost and more rapid turn-around times. In early chemopreventive agent testing for breast cancer chemoprevention, we propose a similar two-step procedure. Epidemiological and/or pathological criteria for risk would be followed by a procedure to obtain cellular material. The cellular material would be assayed for pre-transformational cellular change.Identifying predictive genes in familial breast cancer cohorts such as the modified BRCA1 gene promises to select individuals at high familial and potentially physiological or environmental risk. The identification of the abnormal gene product in individuals and families will provide another important group of subjects for chemopreventive interventions. The identification of high-risk subjects for breast cancer chemoprevention, particularly those with familial genetic risk, carries important ethical problems. Such women may have difficulties obtaining health and life insurance, deciding to have children, and obtaining work. Chemoprevention trials with genetic selection criteria will need to develop methods of dealing with these issues.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 37 (1954), S. 209-216 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die Methoden zur Synthese von Peptiden, welche Diäthylphosphorig- und Diäthylarsenig-säure-amide als Aminüberträberträger benützen, wurden auf ihre Brauchbarkeit zur Herstellung von α-Acylaminosäureamiden, α-Acetamido-zimtsäureamiden und α-Phenylacetamido-acrylsäureamiden geprüft. Im ersten Fall ist das Ergebnis überraschend gut, im zweiten Fall wegen gelegentlicher Nebenreaktionen nur teilweise befriedigend und im dritten Fall praktisch negativ. α-Phenyl-acetamido-acrylsäure-benzylamid konnte nur in geringer Menge hergestellt werden.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 39 (1956), S. 863-871 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wurde die Wirkung von verschiedenen Komplexbildnern (Komplexon, Glycolkomplexon, ATP, ADP u. a.) und von zweiwertigen Kationen (in erster Linie Calcium und Xagnesium) auf das Enzymsystem der α-Ketoglutarsäure-Oxydation nach Von Korff2 untersucht. Die Aminopolycarbonsauren Komplexon und Glycolkomplexon hemmen die Reaktion schon in der Konzentration von 10-4-m. vollstandig. Ein nachtraglicher Zusatz von Calcium im Überschuss führt in beiden Fällen zu einer totalen Reaktivierung, während Magnesium nur im Falle der Komplexonhemmung partiell wirksam ist. Bei Berücksichtigung der Komplexbildungskonstanten kann gefolgert werden, dass Magnesium nur indirekt durch Verdrängung des Calciums aus dem Calcium-Komplexon wirksam ist.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 39 (1956), S. 1525-1528 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: N-Carboxyaminosäureanhydride geben bei der Behandlung mit Halogenwasserstoff in Dioxan reine Chlorid-hydrochloride bzw. Bromid-hydrobromide yon α-Aminosäuren.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...