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Keith C. White Patricia C. Babbitt Douglas D. Buechter George L. Kenyon 《Journal of Protein Chemistry》1992,11(5):489-494
The importance of creatine kinase (E.C. 2.7.3.2) in endocrine tissues has been generally overlooked. Using a specific radiometric assay, we have demonstrated the existence of CK in the Brockmann body (principal islet) of the Coho salmon. We have purified this protein from insular tissue and concurrently purified CK from brain and muscle of the salmon. Purification characteristics, immunological cross-reactivity, and N-terminal sequence analysis have demonstrated that the predominant cytosolic CK from the Brockmann body is indistinguishable from the BB (brain) isoenzyme. Immunocytochemical studies indicated that the enzyme resides in the endocrine parenchyma. Phosphocreatine may serve as a reservoir of energy in the islet and augment its capacity to secrete hormones. The induction of CK-BB in the islet by other hormones could influence the secretion of insular hormones. Interorgan flux of the substrate creatine may be an undescribed mechanism of physiological regulation. 相似文献
156.
George B. Stefano 《Cellular and molecular neurobiology》1992,12(5):357-366
1. Evidence for bidirectional interrelationships between the nervous system and immune systems of vertebrates and invertebrates involving opioid peptides is briefly discussed. 2. The involvement of opioid peptides in autoimmunoregulatory communication also is discussed. 3. The presence of mammalian interleukin-like (1 & 6) and tumor necrosis factor-like molecules in invertebrates is reviewed as well as an apparent cascading system for these signal molecules. 4. The significance of ACTH and MSH in cellular immunosuppression and autoimmunoregulation is discussed in the context of a potential role in schistosomiasis and human immunodeficiency virus actions. 5. The review concludes with the hypothesis that the mammalian immune system has its origin in the invertebrate immune/defense system given the many similarities noted in the review based on new knowledge about the more "primitive" system. 相似文献
157.
Howard R. Hubbell George D. Gibson Robert D. Bigler 《Cancer immunology, immunotherapy : CII》1992,34(4):259-264
Summary Lymphokine-activated killer (LAK) cell activity was measured in human peripheral blood mononuclear cells (PBMC) treated in vitro for 3 days with recombinant interleukin-2 (rIL-2) and mismatched double-stranded RNA (dsRNA). Lytic activity was measured utilizing K562 (NK-sensitive) and 786-0 (NK-resistant) target cells. PBMC cultured with rIL-2 (10–1000 BRMP U/ml) alone showed concentration-dependent lytic activity against the 786-0 target cells, while cells cultured in unsupplemented medium or medium supplemented with mismatched dsRNA (200 µg/ml) alone could not lyse the 786-0 targets. The combination of mismatched dsRNA with suboptimal concentrations of rIL-2 (10–30 U/ml) showed enhancement of both natural killer (NK) and LAK cell activities. The uptake of [3H]thymidine by treated effector cells was dependent on time and rIL-2 concentration and was not increased in the cells treated with low-dose rIL-2/mismatched dsRNA, compared to those treated with low-dose rIL-2 or mismatched dsRNA alone. Similarly, changes in the expression of CD3, CD4, CD8, CD57, CD16 and CD25 cell surface antigens were dependent on rIL-2 concentration and not altered by the presence of mismatched dsRNA. These results indicate that mismatched dsRNA can potentiate rIL-2-induced LAK cell activity by increasing the functional activity per cell, rather than by increasing the number of activated cells. 相似文献
158.
John Greenman Nancy Hogg Suzanne Nikoletti Christopher Slade George Stevenson Martin Glennie 《Cancer immunology, immunotherapy : CII》1992,34(6):361-369
Summary The three forms of Fc receptor carried by monocytes (FcRI, II) and natural killer (NK) cells (FcRIII) are all capable of mediating cell lysis. Here we compare the use of F(ab)2 bispecific antibodies, specifically targetting individual FcR, and chimeric IgG mouse/human antibodies which are capable of targetting all FcR, for their ability to mediate target cell destruction. The derivatives are prepared by linking hinge sulphydryl residues via tandem thioether bonds, using a bismaleimide crosslinker: Fab from an anti-FcR mAb linked to Fab from a common anti-target mAb (BsAb), or Fab from the common anti-target mouse antibody linked to human Fc (FabFc or bisFabFc). All the derivatives targetting chick red blood cells gave efficient lysis, although different effector cell donors yielded differences in both the lytic levels achieved and the comparative efficiencies of derivatives. In contrast, significant lysis of the guinea pig lymphoblastic leukaemia, L2C, regularly resulted only via the anti-FcRIII BsAb and the chimeric derivatives. These results suggest that the chimeric, Fc-containing derivatives mediate tumour cell lysis principally through FcRIII on NK cells. This is in contrast to the situation with the chick red blood cells where the chimeric derivatives appear capable of lysing erythrocytes by utilizing either monocytes or NK cells, because significant (50%) lysis occurred with effector cell populations magnetically depleted through either FcRII or FcRIII. A major difference between these two types of antibody derivative was their ability to function in the presence of high concentrations of normal human Fc. The lysis mediated by BsAb reactive with FcRI or II was unaffected by the presence of human Fc at 2.5 mg/ml (a concentration comparable with that yielded by IgG in plasma) whereas the BsAb recognizing FcRIII and all the Fc-containing derivatives were completely inhibited.This work has been supported by Tenovus, the Cancer Research Campaign, the Leukaemia Research Fund, Italfarmaco, Milano, Italy and the Imperial Cancer Research Fund 相似文献
159.
杨景峰 《Acta Botanica Sinica》1992,34(5):352-359
以高粱(Sorghum bicolor)和大豆(U.S.Soybean)幼苗为材料研究了仅植物很部受到热刺激时,其未直接受到温度影响的叶组织细胞的反应。当13天龄的高粱幼苗根部经受45℃4小时热处理时,发现其未直接受到热刺激的叶细胞内合成了一些异常的蛋白质,估测的分子量分别为80kD、70kD、33kD和17kD。最明显的两条蛋白质谱带是70kD和17kD。6天龄的大豆幼苗,当其根部经受40℃3小时热处理时,在其叶细胞内也检测到两条较为明显的蛋白质谱带,其分子量分别为60kD和17kD。观测到的这些异常蛋白质命名为‘热应激效应蛋白’,并与热应激蛋白在分子量大小分布上进行了比较。另外,还报道了利用蛋白质合成抑制剂,亚胺环己酮(cyclohexlmide)探讨了热应激蛋白与植物热耐性方面的可能关联。 相似文献
160.
Summary A SCUBA-diving survey of the macrobenthos of hard substrata in the sublittoral zone at subantarctic Marion Island was conducted during March and April 1988. Dense beds (12 kg m–2) of the kelp Macrocystis laevis occur in depths > 5 m. Durvillaea antarctica is found along the infralittoral fringe and Desmarestia rossi and Durvillaea sp. occur in a narrow zone from 3 m–6 m. Under-storey algae (chiefly rhodophytes) tend to decrease in biomass with depth, with mean values of 1.57 kg m–2 at 5m, 0.75 kg m–2 at 10m and 0.49 kg m–2 at 15 m. Encrusting coralline algae are particularly abundant in shallow areas (¯x = 0.92 kg m–2) but are insignificant in deeper areas. Total biomass of macrozoobenthos increased with depth with mean values of 0.12 kg m–2 at 5 m, 0.34 kg m–2 at 10 m and 0.46 kg m–2 at 15 m. Polychaetes, crustaceans, echinoderms, molluscs, sponges and bryozoans dominated the macrozoobenthos in terms of biomass. Approximately 200 species of macrobenthic animals were recorded and numerically, polychaetes, crustaceans, molluscs, nematodes and echinoderms dominated. The sublittoral benthos at Marion Island is compared with that occurring at other subantarctic and Antarctic islands, in particular, the Kerguelen Island group. Zoogeographic trends and the possible effects of nutrient input from seabird guano are briefly discussed. 相似文献