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71.
The X-Linked Dystonia-Parkinsonism Syndrome (XDP): Clinical and Molecular Genetic Analysis 总被引:1,自引:0,他引:1
Dystonia and parkinsonism are two major representatives of movement disorders. The X-linked dystonia-parkinsonism syndrome (XDP) serves as a model system for the study of both dystonia and parkinsonism since both symptom complexes occur together and are inherited as Mendelian traits with very high penetrance. XDP, which is endemic to the Philippine island of Panay, originated by a single mutation ("genetic founder effect"), thus assuring homogeneity of the disorder at the molecular level. The disease locus, DYT3, has been assigned to the proximal long arm (Xq12-21.1) of the human X chromosome. A strategy is described to isolate this gene by positional cloning. The rationale of this strategy, the major methods involved and technical terms are explained. 相似文献
72.
Karl-Norbert Klotz Martin J. Lohse Ulrich Schwabe Gloria Cristalli Sauro Vittori Mario Grifantini 《Naunyn-Schmiedeberg's archives of pharmacology》1989,340(6):679-683
Summary The tritiated analogue of 2-chloro-N6-cyclopentyladenosine (CCPA), an adenosine derivative with subnanomolar affinity and a 10000-fold selectivity for A1 adenosine receptors, has been examined as a new agonist radioligand. [3H]CCPA was prepared with a specific radioactivity of 1.58 TBq/mmol (43 Ci/mmol) and bound in a reversible manner to A1 receptors from rat brain membranes with a high affinityK
D-value of 0.2 nmol/l. In the presence of GTP aK
D-value of 13 nmol/l was determined for the low affinity state for agonist binding. Competition of several adenosine receptor agonists and antagonists for [3H]CCPA binding to rat brain membranes confirmed binding to an A1 receptor. Solubilized A1 receptors bound [3H]CCPA with similar affinity for the high affinity state. At solubilized receptors a reduced association rate was observed in the presence of MgCl2, as has been shown for the agonist [3H]N6-phenylisopropyladenosine ([3H]PIA). [3H]CCPA was also used for detection of A1 receptors in rat cardio myocyte membranes, a tissue with a very low receptor density. A KD-value of 0.4 nmol/l and aB
max-value of 16 fmol/ mg protein was determined in these membranes. In human platelet membranes no specific binding of [3H]CCPA was measured at concentrations up to 400 nmol/l, indicating that A2 receptors did not bind [3H]CCPA. Based on the subnanomolar affinity and the high selectivity for A1 receptors [3H]CCPA proved to be a useful agonist radioligand for characterization of A1 adenosine receptors also in tissues with very low receptor density.Abbreviations CHA
N6-cyclopenyadenosine
- CPA
N6-cy-clopentyladen,osine
- CCPA
2-chloro-N6-cyclopentyladenosine
- CCCPA
2-chloro-5-chloro-5-deoxy-N6-cyclopentyladenosine;
- CHAPS
3-[3-(cholamidopropyl)dimethylammonio]-1-propanesulfonate
- DPCPX
8-cyclopentyl-1,3-dipropylxanthine
- NECA
N-ethylcarboxamidoadenosine
- PEI
polyethylenimine
- PIA
N6-phenylisopropyladenosine
Send offprint requests to K.-N. Klotz at the above address 相似文献
73.
Wilhelm D Mansmann U Neudeck H Matejevic D Vetter K Graf R 《Anatomy and embryology》2002,205(5-6):393-400
In a recent study we described an increase of elastic tissue fibres in blood vessel walls of placental stem villi during pre-eclampsia when compared to uncomplicated pregnancies. Furthermore, the thickness of these blood vessel walls was enhanced in pre-eclampsia. Since it is known that elastic tissue fibres increase in systemic hypertension, it may be assumed that the enhancement of elastic tissue fibres in placental stem villi during pre-eclampsia may be induced by the hypertension. To get further insight into this assumption, we examined the amount of elastic tissue fibres in stem villus blood vessels of placentae of pregnancies complicated by intrauterine growth retardation (isolated IUGR, fourteen cases), a disease without hypertension of the mother and such with pre-eclampsia and concomitant IUGR (IUGR+PE, nine cases). Each study group was compared with uncomplicated pregnancies (twenty-six cases). Unfixed cryostat serial sections were processed for conventional orcein staining and for the demonstration of alpha-actin-immunoreactivity. The intensity of orcein staining of stem villus blood vessel walls was evaluated by a semiquantitative score method. Significant lower intensities of orcein staining were calculated for blood vessel walls of placentae of isolated IUGR (P=0.0007) and IUGR+PE (P=0.0039) when compared to uncomplicated pregnancies each. Additionally, the blood vessel wall thickness of stem villi of isolated IUGR (P=0.0081) and IUGR+PE (P=0.0007) was significantly reduced. In comparison to the above mentioned investigation, our results show that, in contrast to isolated pre-eclampsia, elastic tissue fibres are decreased during pregnancies complicated by IUGR, independently of the occurrence of concomitant pre-eclampsia when compared to uncomplicated pregnancies. From our studies it may be considered that the increase of elastic tissue fibres in placentae of patients with isolated pre-eclampsia may be induced by systemic hypertension. Furthermore, our study underline arguments that IUGR may be an independent disease of the fetus. 相似文献
74.
Triantafilou M Brandenburg K Gutsmann T Seydel U Triantafilou K 《Critical reviews in immunology》2002,22(4):251-268
Until recently, consensus was that the mechanism of action of the innate immune system was a simplified one. Current research findings in the field of innate recognition of bacteria suggest that it involves complex associations of receptors depending on cell type and bacterial stimuli, CD14, integrins, Toll-like receptors (TLRs), CD55, ion channels, and activation clusters containing heat shock proteins, chemokine receptor 4 and a plethora of other molecules have been shown to serve as key molecules in bacterial recognition. In this article, we review all the advances in the field and discuss the possibility that the repertoire for recognition of pathogens is defined by the combinational engagement of multiple receptors. 相似文献
75.
Mechanisms of cell adhesion and extracellular matrix formation are primary processes in the interaction with the material surface of an implant which are controlled by integrin receptors. The aim of our study was to find out whether beta1- and beta3-integrins of osteoblastic cells sense the surface topography of titanium, and if structural alterations of integrin adhesions were involved in the organization of fibronectin. Pure titanium surfaces were modified by polishing (P), machining (NT), blasting with glass spheres (GB), and blasting with corundum particles (CB) resulting in increasing roughness. Confocal microscopic investigations revealed fibrillar adhesions of beta1- and alpha5-integrins on P, NT, and GB, but on CB with its sharp edges these integrin subunits did not form fibrillar adhesions. beta3 generally appeared in focal adhesions. We observed aligned fibrillar structures of fibronectin on NT not only on the basal site but interestingly, also on the apical cell surface. In contrast, on CB, fibronectin appeared apically clustered. We suggest that this alignment of fibronectin fibrils depends on the directed actin cytoskeleton and in particular, on the capability of the beta1-integrins to form fibrillar adhesions, which is affected by the surface roughness of titanium. 相似文献
76.
77.
78.
Ulrich Gerlach 《Journal of molecular medicine (Berlin, Germany)》1963,41(17):873-876
Zusammenfassung Aus Rattenherzen wurde ein sulfataktivierendes Enzymsystem extrahiert.Hiermit konnte bei Verwendung von S35O
4
--
markiertes aktives Sulfat (Lipmann) synthetisiert werden.Es zeigte sich, daß die Aktivität des Enzymsystems vom Lebensalter der Versuchstiere abhängig ist. Die biologische Bedeutung des Befundes wird besprochen.Die Deutsche Forschungsgemeinschaft unterstützte in dankenswerter Weise die Arbeit. 相似文献
79.
Neoglycoprotein binding to colorectal tumour cells: Comparison between primary and secondary lesions
Hans -J. Gabius Thomas Grote Sigrun Gabius Ulrich Brinck Lutz F. Tietze 《Virchows Archiv : an international journal of pathology》1991,419(3):217-222
Summary Biotinylated neoglycoproteins are useful to determine the expression of sugar receptors (lectins) histochemically in routinely processed tissue sections. Assessment of the presence of distinct receptor classes with specificity to-galactosides and to- or-N-acetylgalactosamine, selected on the basis of their potential relevance for recognition processes within the metastatic cascade in murine model systems, was performed for a common human tumour type, colorectal cancer. The four different types of neoglycoproteins, derived from covalent attachment of commercially available derivatives of-N-acetylgalactosamine, differed only quantitatively in their capacity to detect specific binding on cultured cells and tissue sections, thus posing no major restriction on the choice of synthetic process for histochemical efficiency of the product. Glycocytological application revealed specific probe binding and a regulation of level of receptor expression for a human colon carcinoma cell line primarily forN-acetylgalactosamine-specific receptors upon retinoic acid-induced differentiation. Monitoring of sections of the 12 cases of primary and secondary colorectal lesions invariably disclosed the presence of the respective receptors, the extent of cell labelling in primary tumours and metastases being similar. Establishment of metastases, even in different target organs, is apparently not followed by a major phenotypic variation in this feature. 相似文献
80.
Ulrich Berger 《Medical microbiology and immunology》1975,161(4):215-229
About 60 characteristics have been investigated in 7 hemolyzing and 12 non-hemolyzing strains ofL. monocytogenes. From these investigations resultedinter alia that the organism grows well under strictly anaerobic conditions, esculin is split at 45°C, NH3 is produced from peptone, but not from arginin, and H2S can be traced by sufficiently sensitive methods. All strains possess a lipase, muramidase, and deoxyribonuclease, the hemolytic ones only also a lecithinase. Besides, the hemolytic strains only dispose of experimental virulence and of a CAMP factor-like agent. The experimental animal of choice seems to be the conjunctivally infected guinea pig in which a generalized infection develops. 相似文献