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1.
Dan B. Lindholm 《Biochemical and biophysical research communications》1982,109(3):805-812
Neuronal perikarya isolated from developing rat brain cortex were employed for studying the effect of hypothyroidism on RNA and protein synthesis in vitro. Neuronal protein synthesis was inhibited by hypothyroidism during the second week of brain development. Thyroxine treatment in vivo stimulated neuronal protein synthesis in hypothyroid rats. The synthesis of neuronal RNA was depressed by hypothyroidism in 7-day old rats. The inhibition of neuronal protein synthesis due to the lack of thyroid hormaones was restricted to membrane-bound ribosomes. The results suggest that the maturation of the neurone is very sensitive to hormonal imbalance during the critical period of brain development. 相似文献
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Accumulation of a peptide toxin from the cyanobacterium Oscillatoria agardhii in the freshwater mussel Anadonta cygnea 总被引:1,自引:0,他引:1
Swan mussels (Anodonta cygnea) were exposed to a toxic strain of the cyanobacterium Oscillatoria agardhii. Mussels accumulated large amounts of the peptide Oscillatoria toxin which was present in low concentrations within the cyanobacterial cells in the test aquaria (40–60 µg Oscillatoria toxin/1). The toxin concentration in the mussels increased during the experiment and after 15 days of exposure the concentration was 70 ± 2 µg/g freeze dried tissue (mean ± range of values). The highest concentration of the toxin (130 µg/g of freeze dried tissue) was found in the hepatopancreatic tissue. The toxin did not seem to be metabolized in the mussels and they were not killed by the high toxin concentrations within them. After two months in clean water still detectable amounts of toxin were present in the mussels. 相似文献
4.
Hans Thoenen Christine Bandtlow Rolf Heumann Dan Lindholm Michael Meyer Hermann Rohrer 《Cellular and molecular neurobiology》1988,8(1):35-40
1. The role of nerve growth factor (NGF) as a retrograde messenger between peripheral target tissues and innervating sympathetic and neural crest-derived sensory neurons is supported by the observations that (a) the interruption of retrograde axonal transport has the same effects as the neutralization of endogenous NGF by anti-NGF antibodies and (b) the close correlation between the density of innervation by fibers of NGF-responsive neurons and the levels of NGF and mRNANGF in their target organs. 2. In situ hybridization experiments have demonstrated that a great variety of cells in the projection field or NGF-responsive neurons is synthesizing NGF, among them epithelial cells, smooth muscle cells, fibroblasts, and Schwann cells. 3. The temporal correlation between the growth of trigeminal sensory fibers into the whisker pad of the mouse and the commencement of NGF synthesis initially suggested a causal relationship between these two events. However, in chick embryos rendered aneural by prior removal of the neural tube or the neural crest, it was shown that the onset of NGF synthesis in the periphery is independent of neurons, and is controlled by an endogenous "clock" whose regulatory mechanism remains to be established. 4. A comparison between NGF synthesis in the nonneuronal cells of the newborn rat sciatic nerve and that in the adult sciatic nerve after lesion provided evidence for the important regulatory role played by a secretory product of activated macrophages. The identity of this product is currently under investigation. 相似文献
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P Fredman T Brezicka J Holmgren L Lindholm O Nilsson L Svennerholm 《Biochimica et biophysica acta》1986,875(2):316-323
The binding specificity of thirteen mouse monoclonal antibodies reacting with Fuc-GM1, Fuc alpha 1-2Gal beta 1-3GalNAc beta 1-4(NeuAc alpha 2-3)-Gal beta 1-4Glc beta 1-1Cer, a ganglioside found to be associated with small cell lung carcinoma (O. Nilsson et al. (1984) Glycoconjugate J. 1, 43-49) was studied. The results are based upon radioimmunodetection of their binding to structurally related glycolipids adsorbed to microtiter plates or chromatographed on thin-layer plates. Four of thirteen antibodies reacted only with Fuc-GM1 and both the fucose and the sialic residues were necessary for binding. Optimal binding was obtained when the sialic acid was N-acetylneuraminic acid. When this sialic acid residue was substituted with N-glycoloylneuraminic acid the binding activity was reduced and up to 10-times more Fuc-GM1 was needed for detection. The ceramide composition did not influence the binding. The other nine monoclonal antibodies cross-reacted with glycolipids containing structures closely related to Fuc-GM1 and differed from the specific ones by recognizing a smaller portion of the carbohydrate moiety in Fuc-GM1. These results indicate that anticarbohydrate monoclonal antibodies, recognizing structures involving a large proportion of the sugar in the glycolipid, possess a high specificity and might be useful for detection of tumor-associated ganglioside antigen. 相似文献
6.
Regional and cellular codistribution of interleukin 1 beta and nerve growth factor mRNA in the adult rat brain: possible relationship to the regulation of nerve growth factor synthesis 总被引:11,自引:1,他引:10 下载免费PDF全文
C E Bandtlow M Meyer D Lindholm M Spranger R Heumann H Thoenen 《The Journal of cell biology》1990,111(4):1701-1711
We have found a regional distribution of IL 1 beta mRNA and IL 1 activity in the normal adult rat brain, which reveals at least partially a colocalization with nerve growth factor (NGF). The predominantly neuronal signal patterns were found over the granule cells of the dentate gyrus, the pyramidal cells of the hippocampus, the granule cells of the cerebellum, the granule and periglomerular cells of the olfactory bulb, and over dispersed cells of the ventromedial hypothalamus and of the frontal cortex. In these areas also the highest levels of IL 1 activity were observed. In the striatum and septum much lower levels of IL 1 beta mRNA and IL 1 activity (shown for the striatum), most likely synthesized by glial cells, could be determined. IL 1 beta-expressing cells were mainly found in brain regions that also synthesize NGF mRNA as shown by in situ hybridization. NGF mRNA could be demonstrated over pyramidal cells of the hippocampus, granule cells of the dentate gyrus, periglomerular cells of the olfactory bulb and over prefrontal cortex neurons. These data indicate that IL 1 beta, among other factors, might also play a regulatory role in the synthesis of NGF in the CNS, as has been demonstrated in the peripheral nervous system (Lindholm, D., R. Heumann, M. Meyer, and H. Thoenen. 1987. Nature (Lond.). 330:658-659). 相似文献
7.
Flow DNA-cytometric findings of paraffin-embedded primary cutaneous melanomas related to prognosis 总被引:1,自引:0,他引:1
C Lindholm P A Hofer H Jonsson B Tribukait 《Virchows Archiv. B, Cell pathology including molecular pathology》1989,58(2):147-151
In a retrospective study flow cytometry was performed in 82 paraffin-embedded clinical stage I cutaneous melanomas. A significant correlation of ploidy to melanoma thickness was found. Using a log rank test ploidy was found significant for prognosis. However, using the Cox's proportional hazard test the influence of ploidy vanished and melanoma thickness or Clark level of invasion together with sex and location were the factors most important for prognosis. 相似文献
8.
Kirsi H Pietil?inen Aila Rissanen Maria Laamanen Anna-Kaisa Lindholm Harri Markkula Hannele Yki-J?rvinen Jaakko Kaprio 《Twin research》2004,7(5):421-429
Weight discordance is very rare in monozygotic (MZ) twin pairs; when found, however, such pairs are advantageous in the search for either environmental or epigenetic causes and consequences of obesity. We analyzed the growth patterns of young adult MZ pairs discordant and concordant for obesity. Screening 5 consecutive birth cohorts (1975-1979) of 22- to 27-year-old Finnish twins (the FinnTwin16 study), we found 14 obesity discordant (Body Mass Index [BMI] difference > or = 4 kg/m2) MZ pairs out of 658. Ten pairs participated in clinical studies. Nine concordant pairs (BMI difference < or = 2 kg/m2) were examined as controls. Lifetime measured heights and weights recorded in hospitals and health centers were traced manually. Height development was similar in all the co-twins of both groups. The weight differences between the co-twins of the discordant pairs began to emerge at 18 years leading to an average discordance of 16.4 kg, 5.6 kg/m2 (p for both = .005) at 25.7 years. The heavier co-twin weighed 221 g (p = .066), 1.0 kg/m2 (p = .01) more already at birth than the leaner, but the differences waned by 6 months of age and reappeared only after adolescence. Both the leaner and the heavier co-twins of the discordant pairs weighed more than expected by the singleton reference values (Cole et al., 1998) after 8 years. The concordant co-twins, on the other hand, grew similarly and after 6 months, their mean growth was not distinguishable from the singleton patterns. Young adulthood represents a critical period of gaining weight irrespective of genetic background in this twin sample. 相似文献
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T. Lindholm 《Hydrobiologia》1982,86(3):297-298
EDTA and oxalic acid in concentrations of about 0.5 mM immobilize several microzooplankton organisms in Baltic Sea water (salinity 5–7 ). Both agents can be used to narcotize ciliates (Mesodinium rubrum, Askenasia sp. and Halteria sp.) and some rotifers (Synchaeta spp.). 相似文献