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The effect of placebo and ACTH-1-17 (Synchrodyn®, Hoechst) upon urinary free cortisol was examined at 5 different circadian stages on 10 men with Steinbrocker Stage II–III rheumatoid arthritis. A mean cosinor analysis of urinary cortisol data from the subjects prior to treatment with either ACTH or placebo revealed a statistically highly-significant rhythm. A circadian variation in a response of urinary free cortisol to a placebo was also seen. Moreover, the response of the midline-estimating statistic of rhythm (rhythm-adjusted circadian average) of urinary free cortisol to ACTH-1-17 by patients with rheumatoid arthritis is circadian rhythmic. This reactivity rhythm is out of phase with the spontaneous rhythm in urinary cortisol acrophases—in the tests limited thus far to midsummer. The further assessment of the circadian component in the context of broader interactions by rhythms with other frequencies in various conditions in health and disease is warranted by the demonstration of rhythms here presented for men with rheumatoid arthritis. 相似文献
3.
Martijn H. Breuning Ella M. van den Berg-Loonen Luigi F. Bernini Jan B. Bijlsma Erna van Loghem P. Meera Khan Lourens E. Nijenhuis 《Human genetics》1977,37(2):131-139
Summary A detailed marker gene study in a large Dutch kindred segregating for a reciprocal translocation between the chromosomes 6 and 20, t(6;20) (p21;p13), revealed a close linkage between the HLA genes and the breakpoint on the short arm of 6. During this study an apparent peak lod score of 2.9 was obtained at a recombination value of 0.05 for a linkage between HLA and the breakpoint, indicating that the chromosomal region, carrying the HLA genes, is situated near the breakpoint in band 6p21 close to the transition to 6p22. 相似文献
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Thyrotropin-releasing hormone (TRH) is not thyrotropic but somatotropic in fed and starved adult chickens. 总被引:2,自引:0,他引:2
E R Kühn M Herremans E Dewil A Vanderpooten P Rudas T Bartha G Verheyen L Berghman E Decuypere 《Reproduction, nutrition, development》1991,31(4):431-439
Adult fed and starved Warren chickens, 2 yr of age, and approaching the end of the second laying year, were injected iv with 1 of the following products: 10 micrograms of thyrotropin releasing hormone (TRH); 100 micrograms of bovine thyrotropin (bTSH); 100 micrograms of ovine growth hormone (oGH); saline. The influence on plasma concentrations of thyroxine (T4), triiodothyronine (T3) or chicken GH (cGH) were followed. Prior to injection, it was clear from the control values that starvation for 3 d decreased plasma levels of T3 and increased cGH, whereas 7 d of fasting increased T4 and cGH. The plasma levels of cGH were elevated greater than 10-fold at 15 min following the TRH challenge in food-deprived chickens compared to a less than 4-fold increase in normal fed hens. This increase was followed by a rise in T3 after 1 h, which was also more pronounced in the starved animals, whereas T4 decreased or remained unaffected. Increases in T4 can, however, be obtained with 100 micrograms TSH in normal fed (2-fold) or starved animals (greater than 3-fold). Following injection of 100 micrograms oGH, a significant increase in T3 levels was observed which in fed animals was already present at 30 min, but the higher levels persisted for 1 and 2 h in fed and starved hens. At the same time, a decrease in T4 was observed in both groups of GH-treated chickens. It is concluded that TRH at the dose used is not thyrotropic but has a somatotropic effect and is responsible for the peripheral conversion of T4 into T3. 相似文献
6.
Daniele Primi Lennart Hammarström Erna Möller C.I.Edvard Smith 《Cellular immunology》1979,47(1):143-152
Activation of splenic lymphocytes with Con A leads to the formation of suppressor cells capable of interfering with the activity of several polyclonal B-cell-activating substances. Thus, these suppressor cells, or their products, most probably act directly on B cells. Suppressor cells could be recovered from the effluent cell population of nylon wool columns, and they were absent from the spleens of athymic nude mice. Furthermore, they were absent from the thymus of normal as well as cortison-treated mice. Cortisone treatment did not abolish the formation of Con A-induced suppressor cells in the spleen. Treatment of activated suppressor cells with antisera specific for distinct products of the H-2 I region revealed that they carried I-J cell surface antigens. We conclude that the suppressor cells in our test system, which unlike other Con A-induced suppressor cell populations have a direct effect on B cells, had antigenic characteristics similar to those previously described for I-J carrying suppressor cells. 相似文献
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Choya Yoon Erna A. Van Niekerk Kenneth Henry Tetsuhiro Ishikawa Sumihisa Orita Mark H. Tuszynski W. Marie Campana 《The Journal of biological chemistry》2013,288(37):26557-26568
Low-density lipoprotein receptors (LRPs) are present extensively on cells outside of the nervous system and classically exert roles in lipoprotein metabolism. It has been reported recently that LRP1 activation could phosphorylate the neurotrophin receptor TrkA in PC12 cells and increase neurite outgrowth from developing cerebellar granule cells. These intriguing findings led us to explore the hypothesis that LRP1 activation would activate canonical neurotrophic factor signaling in adult neurons and promote axonal regeneration after spinal cord injury. We now find that treatment of adult rat dorsal root ganglion neurons in vitro with LRP1 agonists (the receptor binding domain of α-2-macroglobulin or the hemopexin domain of matrix metalloproteinase 9) induces TrkC, Akt, and ERK activation; significantly increases neurite outgrowth (p < 0.01); and overcomes myelin inhibition (p < 0.05). These effects require Src family kinase activation, a classic LRP1-mediated Trk transactivator. Moreover, intrathecal infusions of LRP1 agonists significantly enhance sensory axonal sprouting and regeneration after spinal cord injury in rats compared with control-infused animals (p < 0.05). A significant role is established for lipoprotein receptors in sprouting and regeneration after CNS injury, identifying a novel class of therapeutic targets to explore for traumatic neurological disorders. 相似文献
9.
Wim Van den Ende Dominik Van Wonterghem Peter Verhaert Erna Dewil André Van Laere 《Planta》1996,199(4):493-502
Fructan: fructan fructosyl transferase (FFT, EC 2.4.1.100) was purified from chicory (Cichorium intybus L. var. foliosum cv. Flash) roots by a combination of ammonium sulfate precipitation, concanavalin A affinity chromatography, and anion- and cation-exchange chromatography. This protocol produced a 60-fold purification and a specific activity of 14.5 mol·(mg protein) –1·min–1. The mass of the enzyme was 69 kDa as estimated by gel filtration. On sodium dodecyl sulfatepolyacrylamide gel electrophoresis and mass spectrometry, 52-kDa and 17-kDa fragments were found, suggesting that the enzyme was a heterodimer. Optimal activity was found between pH 5.5 and 6.5. The enzyme used 1-kestose, 1,1-nystose, oligofructan and commercial chicory root inulin (degree of polymerization 10) as donors and acceptors. Sucrose was the best acceptor but could not be used as a donor. However, at higher concentrations sucrose acted as a competitive inhibitor for donors of FFT. 1-Kestose was the most efficient and 1,1-nystose the least efficient donor. The purified enzyme exhibited -fructosidase activity, specially at higher temperatures and lower substrate concentrations. The synthesis of fructans from 1-kestose decreased at higher temperatures (5–50°C). Therefore enzyme assays were performed at 0°C. The same fructan oligosaccharides, with a distribution similar to that observed in vivo, were obtained upon incubation of the enzyme with sucrose and commercial chicory root inulin.Abbreviations Con A
concanavalin A
- DP
degree of polymerization
- FFT
fructan: fructan fructosyl transferase
- Fru
fructose
- Glc
glucose
- Kes
1-kestose
- MALDI-TOF MS
matrix-assisted laser desorption ionisation time of flight mass spectrometry
- Nys
1,1-nystose
- pI
isoelectric point
- SST
sucrose: sucrose fructosyl transferase
- Suc
sucrose
The authors would like to thank E. Nackaerts for valuable assistance. W. Van den Ende is also grateful to the National Fund for Scientific Research (NFSR Belgium) for giving a grant for research assistants. P. Verhaert is a research associate of the NFSR. This work was also supported by grant OT/91/18 from the Research Fund K.U. Leuven. 相似文献
10.
Erwin Roggen Erna Dams Herman Slegers 《Biochimica et Biophysica Acta (BBA) - Gene Structure and Expression》1985,825(1):21-29
Poly(A) polymerase has been purified to near homogeneity from the cytoplasm of Artemia salina as described previously (Roggen, E and Slegers, H. (1985) Eur. J. Biochem. 147, 225–232). Affinity chromatography on poly(A)-Sepharose 4B separates the enzyme preparation into two fractions. In standard assay conditions poly(A) polymerase fraction I (poly(A)-Sepharose 4B unbound) and fraction II (poly(A)-Sepharose 4B bound) have specific activities of 2.4 and 8.0 μmol AMP/h per mg enzyme, respectively. Poly(A) polymerase fraction II shows a high primer specificity towards the 17 S poly(A)-containing mRNP. Depending on the reaction conditions used, poly(A) sequences of 140 ± 15 AMP residues/μg enzyme are synthesized on the latter primer. In contrast, poly(A) polymerase fraction I only elongates oligo(A) primers efficiently. An endogenous RNA is detected in poly(A) polymerase II preparations. This RNA has a length of 83 ± 2 nucleotides and is a component of a 60 kDa particle. After removal of the latter the specificity of poly(A) polymerase fraction II for the 17 S poly(A)-containing mRNP is abolished and the characteristics of the enzyme resemble those of poly(A) polymerase I. 相似文献