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101.
Visualization and characterization of interleukin 1 receptors in brain 总被引:14,自引:0,他引:14
W L Farrar P L Kilian M R Ruff J M Hill C B Pert 《Journal of immunology (Baltimore, Md. : 1950)》1987,139(2):459-463
Interleukin 1 (IL 1) is a polypeptide hormone produced by macrophages, keratinocytes, and brain glial cells which acts as a soluble mediator in immunological and inflammatory reactions. Although its best known effect on the central nervous system is its ability to cause fever, it has been found to influence cell growth, food intake, and slow-wave sleep. We have developed a binding assay for 125I-labeled recombinant murine IL 1 and show it to be highly specific. Additionally, affinity cross-linking studies indicate that the rat brain IL 1 receptor has a m.w. of approximately 80,000, which is similar to the previously described recognition molecule on T cells and fibroblasts. Using autoradiographic techniques, we visualized the distribution of 125I-IL 1 binding in sections of fresh frozen rat brain. IL 1 receptors were found to be widespread throughout the brain, forming a distinctive pattern of distribution. Areas especially dense in receptors were typically neuron-rich sites of the brain such as granule cell layer of the dentate gyrus, the pyramidal cell layer of the hippocampus, and the granule cell layer of the cerebellum as well as in the hypothalamus. The pattern of IL 1 receptor distribution indicates the presence of receptors on neuron cell bodies and the localization to numerous discrete brain areas other than those hypothalamic sites involved in temperature regulation, suggesting a broader role for IL 1 in brain functioning than previously recognized. IL 1, derived from local or systemic sources, may function in the brain to coordinate behavioral and neuroendocrine activities with immunological and inflammatory reactions throughout the body. 相似文献
102.
Sound Stimulates Labeling of Polyphosphoinositides in the Auditory Organ of the Noctuid Moth 总被引:2,自引:1,他引:1
Abstract: The Noctuid moth possesses a simple auditory structure suitable for the investigation of biochemical correlates of sound stimulation in vivo. Stimulation with pulsed tones increased 32 P incorporation into polyphos-phoinositides but not into ATP or other lipids. The effect was seen in the scoloparium (sensory structure) but hot in the nodular sclerite, an adjacent nonsensory tissue. It was also not seen when the stimulus was a continuous tone, leading to adaptation of the action potential. 相似文献
103.
A Candida blankii yeast isolate was grown in sugar cane bagasse hemicellulose hydrolysate at 38 degrees C in carbon-limited chemostat culture. The pretreatment of the acid hydrolysate prior to microbial cultivation consisted of partial neutralization with ammonia and sodium hydroxide, plus the addition of phosphorus, which was the only other growth-limiting nutrient apart from nitrogen. The cell yield coefficient on nitrogen was 16.78. The critical dilution rate was higher (0.35 h(-1)) in diluted hydrolysate than in undiluted hydrolysate (0.21 h(-1)). In undiluted hydrolysate at a dilution rate of 0.1 h(-1) and pH 4, where aseptic procedures proved unnecessary, the cell and protein yield coefficients were 0.53 and 0.26, respectively, and no residual carbon substrates (D-xylose, L-arabinose, D-glucose, and acetic acid) were detected. The cell yield on oxygen increased linearly as a function of dilution rate. The cellular content of protein, carbohydrate, and RNA also increased with an increase in dilution rate, whereas the DNA content decreased slightly. C. blankii has considerable potential for the production of single cell protein from hemicellulose hydrolysate, because of its ability to utilize all of the major carbon substrates in the hydrolysate at a low pH and at a relatively high temperature with a high protein yield. (c) 1992 John Wiley & Sons, Inc. 相似文献
104.
Atrio-ventricular (A-V) block occurring in an anesthetized chacma baboon (Papio ursinus) is analysed. Hemodynamic, 12-lead electrocardiographical (ECG), hematological and biochemical parameters were monitored and data before and after block are compared. Though biochemical and other abnormal values were encountered, no conclusive evidence of the cause of the block was found. 相似文献
105.
Rittig MG Shaw B Letley DP Thomas RJ Argent RH Atherton JC 《Cellular microbiology》2003,5(12):887-899
Following reports that a VacA+cag+ toxigenic but not a VacA-cag- non-toxigenic Helicobacter pylori strain induced homotypic phagosome fusion in murine macrophages, we addressed that phenomenon in human cells. Mononuclear phagocytes and epitheloid cells were challenged with H. pylori strains of different vacA and cag genotypes and with VacA- and Cag- isogenic mutants, and chased in the absence or presence of signal transduction modulators. Electron microscopy revealed that, in monocytes: (i) homotypic phagosome fusion was frequently induced by all live H. pylori strains investigated but not by exogenous VacA; (ii) phagosomes containing bacteria fused, but not those containing latex beads; (iii) fusion resulted in communal compartments resembling giant multivesicular bodies; and (iv) formation of these compartments was blocked by inhibiting the host cell regulators PI 3-kinase, phospholipase C and p42 MAP kinase. Whereas some internalized bacteria remained viable 1 h after uptake, none survived a 24 h period. In contrast to monocytes, infected epitheloid cells rarely developed communal compartments. In combination, these results demonstrate that, in human monocytes, the H. pylori-induced homotypic phagosome fusion depends on neither the vacuolating cytotoxin VacA nor the cag pathogenicity island of H. pylori and does not result in prolonged intracellular survival. 相似文献
106.
In anoxic chemostat cultures of Saccharomyces cerevisiae ATCC 4126 and CBS 8066 grown in a medium containing yeast extract, a sharp increase in the steady-state residual glucose concentration occurred at relatively low dilution rates, contrary to the expected Monod kinetics. However, supplementation with vitamins and amino acids facilitated efficient glucose uptake. This enhanced requirement for growth factors under anoxic conditions and at high growth rates could explain the exceptionally high apparent k
s values for S. cerevisiae reported in the literature. 相似文献
107.
Ekaterina?D.?BadaevaEmail author Alevtina?S.?Ruban Svyatoslav?A.?Zoshchuk Sergei?A.?Surzhikov Helmut?Knüpffer Benjamin?Kilian 《Plant Systematics and Evolution》2016,302(8):943-956
Triticum timopheevii (2n = 4x = 28, GGAtAt) is a tetraploid wheat formerly cultivated in western Georgia. The natural allopolyploid Triticum zhukovskyi is a hexaploid taxon originated from hybridization of T. timopheevii with cultivated einkorn T. monococcum (2n = 2x = 14, AmAm). Karyotypically T. timopheevii and T. zhukovskyi differ from other tetraploid and hexaploid wheats and were assigned to the section Timopheevii of the genus Triticum L. Triticum timopheevii and T. zhukovskyi are resistant to many fungal diseases and therefore could potentially be utilized for wheat improvement. We were aiming to precisely identify all T. timopheevii chromosomes and to trace the evolution of T. zhukovskyi. For this, we developed a set of molecular cytogenetic landmarks based on eleven DNA probes. Each chromosome can now be characterized by two to eight probes. The pTa-535 sequence allows the identification of all At-genome chromosomes, whereas G-genome and some At-genome chromosomes can be identified using (GAA/CTT) n and pSc119.2 probes. The probes pAesp_SAT86, pAs1, Spelt-1, Spelt-52 and 5S and 45S rDNA can be applied as additional markers to discriminate particular chromosomes or chromosomal regions. The distribution of (GAA/CTT) n , pTa-535 and pSc119.2 DNA probes on T. timopheevii chromosomes is distinct from other tetraploid wheats and can therefore be used to track individual chromosomes in introgression programs. Our study confirms the origin of T. zhukovskyi from hybridization of T. timopheevii with T. monococcum; however, we show that the emergence was accompanied by changes involving mostly At-genome chromosomes. This may be due to the presence of two closely related A-genomes in the T. zhukovskyi karyotype. 相似文献
108.
Kilian Dill Sungho Hu Murugan Sutharchanadevi Alan R. Katritzky 《The protein journal》1988,7(4):341-348
The environment of the N-terminal amino groups of glycophorins AM and AN has been studied using13C-NMR spectroscopy and pyrylium salts as amino-blocking agents. The extent of amino blocking was monitored by13C-reductive methylation of the residual free amino groups. The pyrylium ions reacted with the N-terminal amino groups of the two glycophorins at almost identical rates, which is thought to indicate that the overriding steric bulk of the pyrylium salt may determine the rate of the reaction. The difference in the rates of modification of lysine residues of glycophorins AM and AN by the pyrylium ions did indicate that there may exist an environmental difference around the lysine residues between the two glycophorins. This environmental difference may result from solution aggregation of the glycophorin A molecules or from some differences in the pKa values of the five lysine residues found in glycophorins AM and AN. 相似文献
109.
Earlier experiments (T.D. Brock 1975, Planta124, 13–23) addressed the question whether the fungus of the lichen thallus might enable the algal component to function when
moisture stress is such that the algal component would be unable to function under free-living conditions. It was concluded
that the liberated phycobiont in ground lichen thalli could not photosynthesize at water potentials as low as those at which
the same alga could when it was present within the thallus. However, our experience with lichen photosynthesis has not substantiated
this finding. Using instrumentation developed since the mid-1970's to measure photosynthesis and control humidity, we repeated
Brock's experiments. When applying “matric” water stress (equilibrium with air of constant relative humidity) we were unable
to confirm the earlier results for three lichen species including one of the species,Letharia vulpina, had also been used by Brock. We found no difference between the effects of low water potential on intact lichens and their
liberated algal components (ground thallus material and isolated algae) and no indication that the fungal component of the
lichen symbiosis protects the phycobiont from the adverse effects of desiccation once equilibrium conditions are reached.
The photosynthetic apparatus of the phycobiont alone proved to be highly adapted to water stress as it possesses not only
the capability of functioning under extremely low degrees of hydration but also of becoming reactivated solely by water vapor
uptake. 相似文献
110.
Mahsa Mousavi-Derazmahalleh Philipp E. Bayer Bruno Nevado Bhavna Hurgobin Dmitry Filatov Andrzej Kilian Lars G. Kamphuis Karam B. Singh Jens D. Berger James K. Hane David Edwards William Erskine Matthew N. Nelson 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2018,131(4):887-901