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1.
Owing to the exceptional intracellular distribution and the heterogeneous expression pattern during transformation and metastasis
in various tumors, the EF-hand calcium-binding protein S100A2 attracts increasing attention. Unlike the majority of S100 proteins,
S100A2 expression is downregulated in many cancers and the loss in nuclear expression has been associated with poor prognosis.
On the other hand, S100A2 is upregulated in some cancers. This mini review highlights the general characteristics of S100A2
and discusses recent findings on its putative functional implication as a suppressor or promoter in cancerogenesis. 相似文献
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Karin Lindström Albert E. G. Kr. Von Dem Borne Michael E. Breimer Bertil Cedergren Yasuto Okubo Lennart Rydberg Susann Teneberg Bo E. Samuelsson 《Glycoconjugate journal》1992,9(6):325-329
A 12-week-old fetus and one 17-week-old fetus + placenta were obtained after spontaneous abortions from two women of blood group p. The 17-week-old fetus was dissected into intestine, liver, brain and residual tissue. Nonacid glycosphingolipid fractions were prepared from the tissues. Glycolipid characterization was carried out using thin layer chromatography immunostained with monoclonal antibodies and bacteria and by1H NMR spectroscopy and mass spectrometry. In the placental fraction substantial amounts of globotetraosylceramide (P-antigen) and globotriaosylceramide (Pk-antigen) were identified. In contrast, the fetuses contained only trace amounts of these structures, as revealed by immunostaining. These results indicate that the primary target for the antibodies of the anti-Tja serum is the placenta tissue, resulting in termination of the pregnancy. 相似文献
5.
Prof. L. Vollrath M. Karasek B. Kosaras J. Kunert-Radek A. Lewinski 《Cell and tissue research》1985,242(3):607-611
Summary Previous studies have shown that the synaptic ribbons (SR) and spherules (SS) of the mammalian pineal gland may respond differently under physiological and various experimental conditions. The aim of the present study was to gain insight into the mechanisms that may be responsible for the numerical changes of these organelles during a 24-h cycle. As the possibility exists that the structures are influenced by substances synthesized within the pinealocyte, rat pineal glands were cultured with and without added melatonin or serotonin, using an experimental protocol such that the addition of melatonin and serotonin mimicks the circadian changes of the respective substances within the pineal. The tissue was processed for electron microscopy and the numbers of SR and SS were counted in a unit area of pineal tissue. The results obtained indicate that melatonin added to the incubation medium increases the number of SR in the first half of the night; serotonin decreases SR numbers in the morning. SS numbers, by contrast, decrease following melatonin administration in the afternoon, and increase in the morning following serotonin administration. It thus appears that the numbers of SR and SS are influenced by melatonin and serotonin and that the two structures are regulated by differential, but nevertheless biochemically closely related mechanisms.Financial support of the Deutsche Forschungsgemeinschaft (Schwerpunktprogramm Neuroendokrinologie, Vo 135/8-4), the Polish Academy of Sciences (Research Program 10.4.04.6), and the Freunde der Universität Mainz e.V. is gratefully acknowledged.On leave from Department of Anatomy, University Medical School, Pécs, Hungary 相似文献
6.
Fritz Vollrath 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1986,159(2):275-280
summary The effect of gravity on the web building behaviour of the common garden spiderAraneus diadematus was studied in three ways: (i) frames with partially completed vertical webs were swivelled into a horizontal position, (ii) by rotating frames with spiders in a vertical klinostat (1 rpm), and (iii) by vertically rotating a partially completed web treadmill fashion keeping the building animal in a certain position in space.(i) In the horizontal, radial wheels are not constructed, however, a more or less irregular spiral is added to a completed wheel; (ii) in the klinostat the radial wheel lacks the up/down distinction of normal webs, and the spiral is irregular; (iii) in the treadmill the spiral course is abnormal, and the degree of deviation depends on the position of the animal. If the body axis is parallel to gravity the spiral path deviates to both sides of the norm. In ag perpendicular body position the path deviates predominantly to one side, spiralling sharply inwards towards the hub. The observations suggest that the cyclic changes in the body position of spiral-buildingAraneus are an important component of the animal's orientation during this phase of web-construction. 相似文献
7.
Summary In the goldfish, Carassius auratus, morphological and functional aspects of the pituitary gland were studied at the ultrastructural level and six cell types could be distinguished in the pars distalis. Acidophilic cells of the rostral pars distalis were identified as prolactin cells, the chromophobic cells of the rostral pars distalis as ACTH cells, the non-globular basophilic cells of the rostral and the proximal pars distalis as TSH cells, the globular basophils of the proximal pars distalis as gonadotropic cells and the acidophils of the proximal pars distalis as somatotrophs.Besides some of the well established criteria of morphological and functional identification of different cell types, two new approaches have been used in the present study. One was to express the electron density of secretory granules objectively by means of a photometric method. It was found that both types of acidophilic cells which produce the proteohormones prolactin and somatotropin respectively, had granules with the highest electron densities. The basophilic cells producing the glycoproteins gonadotropin and TSH respectively, possessed granules of intermediate electron density whereas the chromophobic cells storing the peptide hormone ACTH had granules of lowest densities. The second new approach was the administration of the synthetic mammalian releasing hormones LH-RP and TRF, which helped in identifying gonadotropic and thyrotropic cells respectively. In the goldfish there is evidence for the presence of only one type of gonadotropic cell.Supported by a grant of the Science Research Council of Great Britain to Professor Sir Francis Knowles, F.R.S. The electron microscope used was provided by the Medical Research Council of Great Britain. The integrating photometer IPM2 was kindly on loan from Messrs. Carl Zeiss, Oberkochen, Germany. For technical advice we are greatly indebted to Mr. P. K. Kaul, B. E., M.I. Struct. E., C. Eng. 相似文献
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Lutz Vollrath 《Cell and tissue research》1969,99(1):146-152
Zusammenfassung In der Neurohypophyse fetaler und neugeborener Ratten entsteht die Mehrzahl der synaptischen Bläschen aus Erweiterungen der Neurotubuli. Ferner können pinocytotische Bläschen als synaptische Vesikel imponieren. Die Bläschenbildung aus Membranen von Elementargranula (vgl. Herlant, 1967) tritt dagegen in den Hintergrund. Ein Auftreten von Vesikeln im Innern von Elementargranula wurde nicht beobachtet.
Mit Unterstützung durch die Deutsche Forschungsgemeinschaft. 相似文献
The origin of synaptic vesicles in neurosecretory axons
Summary In the neurohypophysis of fetal and newborn rats the majority of synaptic vesicles originate from dilatations of neurotubuli. Moreover, pinocytotic invaginations give rise to synaptic vesicles. Evaginations of elementary granule membranes, as described by Herlant (1967), are seldom to be found and do not seem to play an important role in the formation of synaptic vesicles. The occurrence of vesicles within elementary granules was not observed.
Mit Unterstützung durch die Deutsche Forschungsgemeinschaft. 相似文献
10.
Susann Teneberg Timothy R. Hirst Jonas Ångström Karl-Anders Karlsson 《Glycoconjugate journal》1994,11(6):533-540
The binding specificities of cholera toxin andEscherichia coli heat-labile enterotoxin were investigated by binding of125I-labelled toxins to reference glycosphingolipids separated on thin-layer chromatograms and coated in microtitre wells. The binding of cholera toxin was restricted to the GM1 ganglioside. The heat-labile toxin showed the highest affinity for GM1 but also bound, though less strongly, to the GM2, GD2 and GD1b gangliosides and to the non-acid glycosphingolipids gangliotetraosylceramide and lactoneotetraosylceramide. The infant rabbit small intestine, a model system for diarrhoea induced by the toxins, was shown to contain two receptor-active glycosphingolipids for the heat-labile toxin, GM1 ganglioside and lactoneotetraosylceramide, whereas only the GM1 ganglioside was receptor-active for cholera toxin. Preliminary evidence was obtained, indicating that epithelial cells of human small intestine also contain lactoneotetraosylceramide and similar sequences. By computer-based molecular modelling, lactoneotetraosylceramide was docked into the active site of the heat-labile toxin, using the known crystal structure of the toxin in complex with lactose. Interactions which may explain the relatively high toxin affinity for this receptor were found.Abbreviations CT
cholera toxin
- CT-B
B-subunits of cholera toxin
- LT
Escherichia coli heat-labile enterotoxin
- hLT
humanEscherichia coli heat-labile enterotoxin
- pLT
porcineEscherichia coli heat-labile enterotoxin
- EI
electron ionization 相似文献