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  • 1
    ISSN: 1432-0878
    Keywords: Key words: Urothelium ; Tartrate-resistant acid phosphatase ; Nitric oxide synthase I ; Superoxide dismutase ; Immunocytochemistry ; Free radicals ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Three enzymes, viz., tartrate-resistant acid phosphatase (TRAP), nitric oxide synthase I (NOS-I), and superoxide dismutase (SOD), involved in the production and metabolism of free radicals or radical equivalents, were demonstrated by immunocytochemistry in the urothelium of the ureters of six patients of various ages. Two of these enzymes (TRAP and NOS-I) were colocalized in the most apical and lateral border of the superficial cells of the urothelium. In contrast, SOD showed a patchy or granular distribution within the supranuclear region of these cells. Intra- and subepithelial macrophages exhibited a weak TRAP, but no NOS-I or SOD, immune reaction. On the basis of the immunocytochemical findings, arguments in favor of a cytotoxic function of the superficial cells of the human urothelium are presented.
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  • 2
    ISSN: 1432-0878
    Keywords: Key words: NO/cGMP pathway ; Testis ; Leydig cells ; Immunocytochemistry ; RIA ; Cell culture ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. In this study we sought to determine whether the main components of the nitric oxide (NO) pathway are localized within the Leydig cells of the human testis and whether the soluble guanylyl cyclase (sGC), the enzyme that accounts for NO effects, is functionally active in these cells. Using an amplified immunocytochemical technique, immunoreactivity for nitric oxide synthase (NOS-I), sGC and cyclic guanosine monophosphate (cGMP) was detected within the cytoplasm of human Leydig cells. Distinct differences in staining intensity were found between individual Leydig cells, between cell groups and between Leydig cells of different patients. By means of a specific cGMP-RIA, a concentration-dependent increase in the quantity of cGMP was measured in primary cultures of human Leydig cells following exposure to the NO donor sodium nitroprusside. In addition, NOS-I immunoreactivity was seen in Sertoli cells, whereas cGMP and sGC immunoreactivity was found in Sertoli cells, some apically situated spermatids and residual bodies of seminiferous tubules. Dual-labelling studies and the staining of consecutive sections showed that there are several populations of Leydig cells in the human testis. Most cells were immunoreactive for NOS-I, sGC and cGMP, but smaller numbers of cells were unlabelled by any of the antibodies used, or labelled for NOS-I or cGMP alone, for sGC and cGMP, or for NOS-I and sGC. These results show that the Leydig cells possess both the enzyme by which NO is produced and the active enzyme which mediates the NO effects. There are different Leydig cell populations that probably reflect variations in their functional (steroidogenic) activity.
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  • 3
    ISSN: 0044-2313
    Keywords: Cr carbonyl complexes of Tris(trimethylsilyl)heptaphosphanortricyclene; ; (Me3Si)3P7[Cr(CO)5]1-3; ; (Me3Si)3P7[Cr(CO)5][Cr(CO)4]; ; (Me3Si)3P7[Cr(CO)5]2 × [Cr(CO)4]; ; (Me3Si)3P7[Cr(CO)5]3[Cr(CO)4] ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Formation and Structures of Chromium Carbonyl Complexes of Tris(trimethylsily)heptanortricyclane (Me3Si)3P7(Me3Si)3P7 1 reacts with one equivalent of Cr(Co)5THF 2 to give the yellow (Me3Si)3P7[Cr(Co)5]4. The Cr(Co)5group is attached to a Pe atom. Yellow (Me3Si)3P7[Cr(CO)5]2 5 is obtained either from reacting 1 with two equivalents of 2, or from 4 with one equivalent of 2. One Cr(CO)5 groups in 5 is coordinated to a Pe atom, the other one to a P,b atom. Similarly, Yellow (Me3Si)3P7[Cr(CO)5]3 6 results from reacting 5 with one equivalent of 2. Two Cr(CO)5 groups in 6 are linked to Pb atoms, and the third one either to a Pe or the Pa atom (assignment not completely clear).Derivatives containing a Pe bridge appear in reactions of 1 with higher amounts of 2. Such, 5 forms mixtures of the red compounds (Me3Si)3P7 × [Cr(CO)5]2[Cr(CO)4] 8 and (Me3Si)3P7[Cr(CO)5] × [Cr(CO)4] 9, and even preferably 9 with four equivalents of 2. In 8, one Cr(CO)5 group is attached to that pe atom which is not engaged in the Cr(CO)4 bridge, and the second to one of the Pb atoms directly adjacent to the bridge. The additional Cr(CO)5 group in 9 is coordinated to the remaining Pb atom directly adjacent to the bridge. In reactions of 5 with even higher amounts of 2, four Cr(CO)5 groups and one Cr(CO)4 bridge attach to the basic P7 skeleton to from the less stable Me3P7[Cr(CO)5]4[Cr(CO)4]. (Me3Si)3P7 1 reacts considerably slower with Cr(CO)5THF 2 than R3P7 (R = Et, iPr).Cr(CO)4NBD 3 reacts with 1, but it was not possible to isolate (Me3Si)3P7[Cr(CO)4]. However, 4 with 3 forms (Me3Si)3P7[Cr(CO)5][Cr(CO)4] 7, and 5 with 3 yields (Me3Si)3P7[Cr(CO)5]2[Cr(CO)4] 8.The structures of 4, 5, 7, 8 or 9 are quite analogous to those of the derivatives of Et3P7 but there exist significant differences in stability and reactivity. While Et3P7[Cr(CO)5]2 in solution rearranges to give the stable Et3P7[Cr(CO)5][Cr(CO)4], the analogous (Me3Si)3P7[Cr(CO)5][Cr(CO)4] 7 is not stable and is not obtained from (Me3Si)3P7[Cr(CO)5]2 5. Et3P7[Cr(CO)5]3 can just be detected spectroscopically and rearranges easily to give Et3P7[Cr(CO)5]2 [Cr(CO)4] whereas (Me3Si)3P7[Cr(CO)5]3 6 can be isolated. These differences are caused by the greater steric requirements of Me3Si groups. The formation of a Pe-Cr(CO)4-Pe bridge, e.g., requires a Me3Si group in 1 to switch from the s to the as position.Whereas many of the complex compounds of R3P7 (R = Et, iPr) crystallize easily, the analogous derivatives of (Me3Si)3P7 did not yield crystals. The structures of the products were assigned by evaluating the coordination shift in their 31P NMR spectra and by comparision of these spectra with those of such derivatives of Et3P7 which previously had been investigated by single crystal structure determinations.
    Notes: (Me3Si)3P7 1 bildet mit einem Mol Cr(CO)5THF2 (Me3Si)3P7[Cr(CO)5] 4 (gelb), in dem die Cr(CO)5-Gruppe an einem Pe-Atom gebunden ist. (Me3Si)3P7[Cr(CO5]2 5 (gelb) entsteht aus 1 mit zwei Mol Cr(CO)5THF 2 bzw. aus 4 mit einem Mol 2. In 5 ist eine Cr(CO)5-Gruppe an ein Pe-Atom, die zweite an ein Pb-Atom gebunden. (Me3Si)3P7[Cr(Co)5]3 6 (gelb) bildet sich aus 5 mit einem Mol 2. In 6 sind zwei Cr(CO)5-Gruppen an Pb-Atome gebunden, die dritte an das Pa- oder ein Pe-Atom (Zuordnung nicht eindeutig).Bei Umsetzungen von 1 mit höheren Molzahlen 2 bilden sich Derivate mit der Pe-Cr(CO)4-Pe-Brücke. So entstehen aus 5 mit zwei bzw. drei Äquivalenten 2 die roten Verbindungen (Me3Si)3P7[Cr(CO)5]2[Cr(Co)4] 8 und (Me3Si)3P7[Cr(Co)5]3[Cr(Co)4] 9, mit vier Äquivalenten 2 bevorzugt 9. In 8 verbrückt die Cr(Co)4- Gruppe zwei Pe- Atome. Eine Cr(Co)5-Gruppe ist an das dritte Pe- Atom Koordiniert, die zweite an ein Pb-Atom, das direkt mit dem Pe- Atom der Cr(Co)4-Brücke verbunden ist. 9 leitet sich von 8 ab durch Einführung einer weiteren Cr(Co)5-Gruppe an das zweite P6-Atom, das mit dem zweiten Pe-Atom an der Cr(Co)4-Brücke verbunden ist. Bei Umsetzungen von 5 mit noch höheren Molzahlen an 2 lagern sich an 1 insgesamt vier Cr(CO)5- und eine Cr(CO)4-Gruppe an unter Bildung einer weniger beständigen Verbindung (Me3Si)3P7[Cr(Co)5]4[Cr(CO)4]. (Me3Si)3P71 reagiert mit Cr(CO)5 THF 2 erheblich langsamer als R3P7 (R = Et, iPr).Die Umsetzung von 1 mit Cr(CO)4NBD 3 ermöglicht nicht die Isolierung von (Me3Si)3 P7[Cr(CO)4]. Jedoch bildet 3 mit (Me3Si)3P7[Cr(CO)5)] 4 (Me3Si)3P7[Cr(CO)5]× [Cr(CO)4] 7 und mit (Me3Si)3P7[Cr(CO)5]2 5 (Me3Si)3P7[Cr(CO)5]2[Cr(CO)4] 8.Die Verbindungen 4,5,7,8,9 entsprechen in ihrem Aufbau weitgehend den Derivaten des Et3P7, jedoch bestehen gravierende Unterschiede bezüglich Stabilität und Reaktivität. Während sich Et3P7[Cr(Co)5]2 in Lösung zum stabilen Et3P7[Cr(Co)5][Cr(Co)4] umlagert, ist das analoge (Me3Si)3P7[Cr(Co)5][Cr(Co)4] 7 instabil und wird nicht aus (Me3Si)3 P7[Cr(CO)5]2 5 gebildet. Et3P7[Cr(CO)5]3 ist nur spektroskopisch nachweisbar und lagert sich leicht um zum Et3P7[Cr(CO)5]2×[Cr(CO)4], während (Me3Si)3P7[Cr(CO)5]3 6 zu isolieren ist. Die Unterschiede sind durch den größeren Raumbedarf der Me3Si-Gruppe bedingt. So gehen die Me3Si- Gruppen am (Me3Si)3P7 bei Einführung der Pe-Cr(CO)4-Pe-Brücke aus ihrer s- in die as- Position über.Während die Komplexverbindungen des R3P7 (R = Et, iPr)teilweise gut kristallisieren, konnten von denen des (Me3Si)3P7 keine kristalle erhalten werden. Die Strukturen der Verbindungen wurden durch Auswertung der Koordinationsverschiebung im 31P-NMR Spektrum und durch Vergleich mit Spektren von - durch Kristallstrukturuntersuchung gesicherten - Derivaten des Et3P7 abgeleitet.
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