共查询到20条相似文献,搜索用时 31 毫秒
1.
Fujio Suzuki Richard B. Pollard Hiroshi Maeda 《Cancer immunology, immunotherapy : CII》1989,30(2):97-104
Summary The development of non-specific resistance to tumors following stimulation with poly(maleic-acid-styrene)-conjugated neocarzinostatin (SMANCS), a polymer-conjugated derivative of neocarzinostatin, was investigated in mice. The growth of syngeneic solid tumors (Meth-A fibrosarcoma and RL 1 leukemia) inoculated into BALB/c mice was suppressed after one treatment with SMANCS at doses ranging from 0.14 mg/kg to 3.4 mg/kg i.v. 24 h before tumor implantation. Since previously observations concerning SMANCS have shown that it disappeared within 1.5 h after i.v. administration in mice and that it was inactivated quickly in plasma, SMANCS evidently inhibited tumor growth by mediating non-specific resistance. In addition, the non-specific resistance to tumors stimulated by SMANCS could be passively transferred to untreated mice by serum which was shown to contain interferon (IFN) from 12 h to 20 h after SMANCS administration. However, the resistance was not produced by serum prepared from mice at 8 h or 32 h after administration presumably because of the observation that the interferon activity was only demonstrated from 12 h to 28 h after SMANCS stimulation. When the serum specimens were treated with anti-IFN- antiserum, the antitumor activity of the sera was abrogated. However, no significant change was detected in the antitumor activity of the specimens following treatment with anti-IFN-/ antiserum. Treatment of mice with SMANCS and anti-IFN- antiserum together resulted in the elimination of the non-specific resistance to tumors. The IFN induced in the sera of mice by SMANCS was shown to be 57% IFN- and 41% IFN-/. Half of the interferon produced in SMANCS-stimulated mice could be eliminated by treatment with anti-IFN-, and treatment of SMANCS-stimulated mice with both anti-IFN- and anti-IFN-/ antisera resulted in a total absence of detectable interferon. These findings suggest that while the administration of SMANCS induces both IFN- and IFN-/ production, in this case, it is only the former which mediates the non-specific resistance to tumors. 相似文献
2.
Dr. R. V. Nair T. M. Masajo G. S. Khush 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1982,61(1):19-22
Summary The inheritance of resistance to whitebacked planthopper Sogatella furcifera (Horvath) was studied in 21 rice varieties. Reactions of F1; F2 and F3 progenies of the crosses of 21 resistant varieties with the susceptible variety TN 1 revealed that a single dominant gene governs resistance in Mushkan 41, Santhi, Siahnakidar 195, SM2-34, Tirisurkh 251, Zirijowaian 245, 18, 24A, 39, 76 S, 78, 180, 213 B, 267, 293, CI 6037-4, NP97, S39 JKW and Bansphul. In varieties 65 and 274 A, resistance is governed by one dominant and one recessive gene which segregate independently of each other. Tests for allelism with the Wbph 1 gene originally identified in N 22 revealed that the dominant gene present in all the test varieties is the same as Wbph 1. Further studies are required to determine the allelic relationships of the recessive gene found in varieties 65 and 274 A. 相似文献
3.
Summary An abnormal short-lived female infant with almost complete trisomy 13 (pterq32 or 33) and partial monosomy 15 (pterq14 or 15) resulting from an adjacent 2 meiotic disjunction of a paternal reciprocal translocation is described. Cases with monosomy of chromosome 15 material are reviewed. It appears likely that monosomy of an interstitial long arm segment, approximating to 15q2124, imparts the lethality associated with the full monosomic condition. Adjacent 2 disjunction in man has been further characterised by reviewing the literature. 相似文献
4.
Yoshinori Fukui Yukio Esaki Akinori Kimura Katsuiku Hirokawa Yasuharu Nishimura Takehiko Sasazuki 《Immunogenetics》1993,37(3):204-211
We have established a strain of transgenic mice in which the HLA-DRA gene was integrated into the X-chromosome and the xenogeneic mixed isotype molecule, DREb, was expressed in a cell type-specific manner, although the transgenic DRA gene contained only 268 base pairs of the 5-flanking region. The DREb molecules expressed in the transgenic mice functioned as major histocompatibility complex (MHC) class II to select T-cell repertoire, and to stimulate mixed lymphocyte reaction. In female transgenic mice homozygous for HLA-DRA (DR-B6-F-homo) and male transgenic mice (DR-B6-M), DREb molecules were expressed in almost all of the MHC class II Ab-positive cells. In contrast, the expression of DREb molecules in female transgenic mice hemizygous for HLA-DRA (DR-B6-F-hemi) was found only in part of the Ab positive cells, and the proportion of cells expressing the DREb molecules varied due to random inactivation of one of the X-chromosomes. Clonal deletions of the T cells and mature thymocytes bearing Tcrb-V5 and Tcrb-V11, which are eliminated from the peripheral repertoire in mice expressing self-superantigen and MHC class II E molecules, were incomplete in DR-B6-F-hemi as compared with those in DR-B6-F-homo, and were correlated with the proportion of DREb-positive spleen cells. These observations suggested that the number of bone marrow-derived cells expressing DREb molecules was critical for clonal deletions of Tcrb-V5+ and Tcrb-V11+ T cells in the thymus. 相似文献
5.
Summary In this first article on the carotenoids of Myxobacterales we report on the minor carotenoids of Stigmatella aurantiaca: phytoene, phytofluene, lycopene, -carotene, 4-keto--carotene, 1,2-dihydro-1-hydroxy--carotene, 4-keto-1,2-dihydro-1-hydroxy--carotene, 4-keto-1,2-dihydro-1-hydroxy-torulene, and 1,2,1,2-tetrahydro-1,1-dihydroxy-lycopene. These pigments account for about 10% of total carotenoids. 相似文献
6.
Summary The ratio of deuterium to hydrogen (expressed as D) in hydrogen released as water during the combustion of dried plant material was examined. The D value (metabolic hydrogen) determined on plant materials grown under controlled conditions is correlated with pathways of photosynthetic carbon metabolism. C3 plants show mean D values of-132 for shoots and -117 for roots; C4 plants show mean D values of -91 for shoots and-77 for roots and CAM plants a D value of-75 for roots and shoots. The difference between the D value of shoot material from C3 and C4 plants was confirmed in species growing under a range of glasshouse conditions. This difference in D value between C3 and C4 species does not appear to be due to differences in the D value (tissue water) in the plants as a result of physical fractionation of hydrogen isotopes during transpiration. In C3 and C4 plants the hydrogen isotope discrimination is in the same direction as the carbon isotope discrimination and factors contributing to the difference in D values are discussed. In CAM plants grown in the laboratory or collected from the field D values range from-75 to +50 and are correlated with 13C values. When deprived of water, the D value (metabolic hydrogen) in both soluble and insoluble material in leaves of Kalanchoe daigremontiana Hamet et Perr., becomes less negative. These changes may reflect the deuterium enrichment of tissue water during transpiration, or in field conditions, may reflect the different D value of available water in areas of increasing aridity. Whatever the origin of the variable D value in CAM plants, this parameter may be a useful index of the water relations of these plants under natural conditions. 相似文献
7.
Maria Werner-Wasik Wittiches von Muenchhausen James P. Nolan Stefan A. Cohen 《Cancer immunology, immunotherapy : CII》1989,28(2):107-115
Summary Nonparenchymal liver cells from untreated C3HeB/FeJ mice, when incubated in medium containing-10% fetal bovine serum or portal serum, produced significant amounts of interferon alpha/beta (IFN/). In contrast, other cell populations (spleen, mononuclear blood cells and peritoneal cells) from C3HeB/FeJ mice or nonparenchymal liver cells from other strains of mice (C3H/HeJ, germ-free C3H/HeN and C57Bl/6J) produced little or no detectable IFN in fetal bovine serum under the same culture conditions. The cells in the nonparenchymal liver cell population responsible for IFN/ production were adherent, phagocytic, silica-sensitive, carbonyl-iron-sensitive, and Thy1.2–, presumably Kupffer cells or resident liver macrophages. IFN/ production by cultured Kupffer cells was not observed if medium containing fetal bovine serum or portal serum was treated with polymyxin B or if Kupffer cells were cultured in serum-free medium. This suggested that small amounts of endotoxin in fetal bovine or portal serum stimulated Kupffer cells to produce IFN/. Possibly, Kupffer cells are in a different state of activation/maturation than peritoneal and splenic macrophages since the sensitivity of resident Kupffer cells from C3HeB/FeJ mice to the stimulatory effects of endotoxin. The endogenous production of IFN/ by Kupffer cells from C3HeB/FeJ mice can augment liver-associated natural killer (NK) activity against YAC-1 cells (4 h) and induce liver-associated cytotoxic activity, not restricted by the major histocompatibility complex, against NK resistant P815 mastocytoma cells (18 h).This work was supported by National Institutes of Health grant CA28835, VA Merit Grant and by the Margaret Duffy and Robert Cameron Troup Fund
Abbreviations used: NPC, nonparenchymal liver cells; FBS, fetal bovine serum; IFN, interferon; -AsGm-1, anti-asialo-GM1; -Thy1.2, anti-Thy1.2; Hepes, 4-(2-hydroxyethyl)1-piperazineethanesulfonic acid; HBSS, Hanks' balanced salt solution; GBSS, Gey's balanced salt solution; SRBC, sheep red blood cells; Ab, mouse anti-SRBC; NK, natural killer; MHC, major histocompatibility complex; polyI·polyC, polyinosinec·polycytidylic acid 相似文献
8.
J. J. Bredman A. Wessels W. A. Weijs J. A. M. Korfage C. A. S. Soffers A. F. M. Moorman 《The Histochemical journal》1991,23(4):160-170
Summary Human and rabbit masticatory muscles were analyzed immuno-and enzyme-histochemically using antibodies specific to cardiac , slow and fast myosin heavy chain isoforms. In human masseter, temporalis, and lateral pterygoid muscle cardiac myosin heavy chain is found in fibres that contain either fast, or fast and slow myosin heavy chain. In rabbit masseter, temporalis and digastric muscles, fibres are present that express cardiac myosin heavy chain either exclusively, or concomitantly with slow myosin heavy chain or fast myosin heavy chain. Our results demonstrate a much broader distribution of cardiac myosin heavy chain than hitherto recognized and these might explain in part the specific characteristics of masticatory muscles. The cardiac myosin heavy chain is only found in skeletal muscles originating from the cranial part of the embryo (including the heart muscle) suggesting that its expression might be determined by the developmental history of these muscles. 相似文献
9.
Irene M.A. Nooren Ke-Yu Wang Philip N. Borer István Pelczer 《Journal of biomolecular NMR》1998,11(3):319-328
The subject RNA models the binding site for the coat protein of the R17 virus, as well as the ribosome recognition sequence for the R17 replicase gene. With an RNA of this size, overlaps among the sugar protons complicate assignments of the 1H NMR spectrum. The cross peaks that overlap significantly in 2D-NOE spectra can frequently be resolved by introducing a third, in our approach the double-quantum, frequency axis. In particular the planes in a 3D-NOE/2QC spectrum perpendicular to the 2Q axis are extremely useful, showing a highly informative repeating NOE-2Q pattern. In this experiment substantial J-coupling confers special advantages. This always occurs for geminal pairs (H5/H5 for RNA plus H2/H2 for DNA), as well as for H5/H6, for H3/H4 in sugars with substantial populations of the N-pucker, for H1/H2 for S-puckered sugars, and usually for H2/H3. For the 24-mer RNA hairpin the additional information from the 3D-NOE/2QC spectrum allowed assignment of all of the non-exchangeable protons, eliminating the need for stable-isotope labeling. 相似文献
10.
Summary A family with one homozygote and three heterozygotes for hemoglobin Stanleyville II (78 AsnLys) has been analyzed by -globin gene mapping. The pattern of restriction fragments with the enzymes BamHI and BglII demonstrated that the globin variant is associated with a 3.7-kb -globin gene deletion. 相似文献
11.
D. G. Cochran M. H. Ross 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1984,67(2-3):123-129
Summary A stock of Blattella germanica bearing the interchange T(3; 12)/3;12 was subjected to close inbreeding with selection for random disjunction at metaphase I. After 3–4 generations of selection, interchange quadrivalent chiasma frequency decreased, variability in free bivalent chiasma frequency increased sharply, and individuals with either random or directed disjunction were present in the stock. Random disjunction was modified from a ratio of 2112 (adj.-1; alt.-1; adj.-2; alt.-2) to a ratio of 1111. After 7–8 generations of selection, chiasma frequency appeared to stabilize at lower than normal levels and variability decreased for both quadrivalents and free bivalents. Directed disjunction was modified from a ratio of 2114 to 1112, and no individuals with the original high level of directed disjunction were detected. Chains-of-four tended to orient randomly, especially in individuals where the ring quadrivalents showed directed disjunction. Relaxation of inbreeding, but not selection, produced an increase in chiasma frequency and variability in both free bivalents and quadrivalents, but the modified ratios for both random and directed disjunction were retained. These results are discussed with respect to inbreeding effects and genetic control of chiasma frequency and metaphase I disjunction in interchange quadrivalents. 相似文献
12.
Liying Yan Patricia P Wilkins Gerardo Alvarez-Manilla Su-Il Do David F Smith Richard D Cummings 《Glycoconjugate journal》1997,14(1):45-55
A defined set of oligosaccharides and glycopeptides containing -linked fucose were used to examine the specificity of the immobilized fucose-binding lectin Lotus tetragonolobus agglutinin (LTA1), also known as lotus lectin. Glycans containing the Lewis x determinant (Lex) Gal1-4[Fuc1-3]GlcNAc1-3-R were significantly retarded in elution from high density LTA-Emphaze columns. The lectin also bound the fucosylated lacdiNAc trisaccharide GalNAc1-4[Fuc1-3]GlcNAc. The lectin did not bind glycans containing either sialylLex or VIM-2 determinants, nor did it bind the isomeric Lea, Gal1-3[Fuc1-4]GlcNAc-R. Although 2-fucosyllactose Fuc1-2Gal1-4Glc) was retarded in elution from the columns, larger glycans containing the H-antigen Fuc1-2Gal1-3(4)GlcNAc-R interacted poorly with immobilized LTA. Our results demonstrate that immobilized LTA is effective in isolating glycans containing the Lex antigen and is useful in analyzing specific fucosylation of glycoconjugates. Abbreviations: LTA, Lotus tetragonolobus agglutinin; UEA-1, Ulex europaeus agglutinin-I; LNT, AAL, Aleuria aurantia agglutinin; Gal1-3GlcNAc1-3Gal1-3Glc; LNnT, Gal1-4GlcNAc1-3Gal1-3Glc; Lex, Lewis x antigen; Lea, Lewis a antigen; GDPFuc, guanosine 5-diphosphate--L-fucose 相似文献
13.
Menno P. Gerkema Floris van der Leest 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1991,168(5):591-597
Summary The timing mechanism underlying ultradian (2–3 h) activity patterns in the common vole, Microtus arvalis, was studied using behavioural deprivation experiments. These were aimed at distinguishing between a homeostatic control mechanism, in which the rhythmic behaviour itself is part of the causal loop, and a clock mechanism, independent of the behaviour.In 175 experiments, deprivation of food during 3 ultradian cycles in (subjective) daytime did not result in significant changes in the ultradian periodicity of attempts to obtain the food, compared with ad lib. access to food and water. A minor, but significant increase in ultradian activity time () occurred in the course of the deprivation, but this was compensated by a shorter ultradian rest (). These results were obtained both in intact animals (n = 24), which showed ultradian and circadian rhythmicity in behaviour, and in animals (n = 21) with electrolytic lesions aimed at the suprachiasmatic nuclei (SCN), which lacked the circadian modulation of behaviour. Simultaneous deprivation of water and food in 8 voles without circadian rhythmicity during 40 experiments also did not lead to any change in the ultradian periodicity of feeding attempts.Rest deprivation was studied in 5 SCN lesioned voles, by forcing running wheel activity to continue following spontaneous running. Thus, the experimental activity bout was artificially lengthened to 2–9 h in 67 experiments. The onset of the subsequent rest episodes occurred independent of the duration of the preceding . The duration of was dependent on the preceding, experimental in a periodic fashion. The interval experimental (=lengthened +following ) was equal to one, two or three times the control (obtained on nonexperimental days). This result fits the prediction of a clock model and is in conflict with a monotonicincrease of with , as expected in a homeostatic, restorative process.It is concluded that the ultradian timing of activity in the common vole can be explained neither by homeostatic hunger or thirst mechanisms nor by homeostatic rest/activity regulation. The results strongly suggest an independent clock system generating ultradian feeding rhythms in the common vole.Abbreviations
DD
continuous darkness
-
LD
light-dark regime
-
LL
continuous light
-
RCA
retrochiasmatic area
-
ARC
arcuate nucleus
-
SCN
suprachiasmatic nuclei
-
ultradian period
-
ultradian activity time
-
ultradian rest time 相似文献
14.
Hiroko Yamazaki Takaaki Nishijima Yoichi Yamato Megumi Hamano Masaji Koshioka Hiroyuki Miura 《Plant Growth Regulation》1999,29(3):195-200
The content of abscisic acid (ABA) in bulbs of two Allium wakegi Araki cultivars, Kiharabansei No. 1 (dormant type) and Ginoza (nondormant type), was similar and changed similarly during the development and storage of the bulbs. It increased during bulb development, reached a maximum shortly after bulb harvesting, and gradually decreased during bulb storage. The bulbs of Kiharabansei No. 1 showed dormancy correlated with the change in ABA content, but those of Ginoza did not show significant dormancy throughout the experimental period. The ABA content in the buds of dormant bulbs of Kiharabansei No. 1 did not change after planting of bulbs, but that of nondormant bulbs of Ginoza planted on the same day rapidly decreased after planting. Application of ABA to bulbs delayed sprouting of both cultivars, but dormant bulbs of Kiharabansei No. 1 had higher sensitivity to ABA than the bulbs of Ginoza or the bulbs of Kiharabansei No. 1 partly released from dormancy. These results suggest that the decrease in the ABA content after planting (watering) and low sensitivity to ABA are correlated with the nondormancy of Ginoza. 相似文献
15.
Shcheglovitov A. K. Zhelay T. I. Kondratskii A. P. Naidenov V. G. Shuba Ya. M. 《Neurophysiology》2004,36(2):93-101
We analyzed the effects of nifedipine on a family of recombinant low-threshold Ca2+ channels functionally expressed in Xenopus oocytes and formed by three different subunits (1G, 1H, and 1I). The 1G and 1I channels demonstrated a low sensitivity to nifedipine even in high concentrations (IC50 = 98 and 243 M, maximum blocking intensity Amax = 25 and 47%, respectively). At the same time, the above agent effectively blocked channels formed by the 1H-subunit (IC50 = 5 M and Amax = 41%). The nifedipine-caused effects were voltage-dependent, and their changes depended on the initial state of the channel. In the case of 1G-subunits, the blockade was determined mostly by binding of nifedipine with closed channels, whereas in the cases of 1H- and 1I-subunits this resulted from binding of nifedipine with channels in the activated and inactivated states. The obtained data allow us to obtain estimates of the pharmacological properties of the above three subtypes of recombinant channels and, in the future, to compare these characteristics with the properties of low-threshold Ca2+ channels in native cells. 相似文献
16.
The distribution and frequency of chiasmata have been analyzed in male BALB/c mice. Bivalents were classified in terms of the number of interstitial chiasmata (CH) and terminal associations (TA) present as follows; 1CH, 2CH, 1TA, 2TA, 1CH·1TA, 1CH·2TA, 2CH·1TA, 2CH-2TA and 0. We provide evidence that the TA frequently dissociates during 1st meiotic prophase. Consequently six of the observed bivalents may be derived from three basic bivalent types (namely 2CH·2TA, 1CH·2TA and 2TA) by dissociation of the TA according to the following schemas: (1) 2CH·2TA2CH·1TA2CH, (2) 1CH·2TA1CH·1TA1CH, and (3) 2TA1TA0. We also provide evidence that interstitial chiasmata do not move, which implies that a TA can not be formed by chiasma terminalization. The chiasma frequency estimated by assuming that terminal associations do not result from terminalized chiasmata is 17.2±2.4 compared to a value of 25.4±2.2 calculated on the assumption of chiasma terminalization. 相似文献
17.
Summary When a very large number of phytosociological types have to be compared, a reduction of the number of relevés is desirable. In this paper a method of relevé selection from given phytosociological tables is suggested. The method is based on a sum of squares criterion. The advantage, in comparison with other selection procedures, is that this method provides a means on the basis of which the efficiency of a relevé selection can be objectively measured.Contribution from the Working Group for Data-Processing in Phytosociology, International Society for Vegetation Science.The work was completed at the Department of Plant Sciences of the University of Western Ontario, London, Canada. We wish to thank Prof. L. Orlóci for the hospitality and the helpful discussions. The work was supported by Italian C.N.R., within the project Promozione qualità dell'ambiente subproject Metodologie matematiche e basi di dati. 相似文献
18.
Functional specialization of CK2 isoforms and characterization of isoform-specific binding partners 总被引:1,自引:0,他引:1
In mammals, protein kinase CK2 has two isozymic forms of its catalytic subunit, designated CK2gr; and CK2. CK2 and CK2 exhibit extensive similarity within their catalytic domains but have completely unrelated C-terminal sequences. To systematically examine the cellular functions of each CK2 isoform in mammalian cells, we have generated human osteosarcoma U2-OS cell lines with the expression of active or inactive versions of each CK2 isoform under the control of an inducible promoter [22]. Examination of these cell lines provides evidence for functional specialization of CK2 isoforms at the cellular level in mammals with indications that CK2 is involved in the control of proliferation and/or cell survival. To understand the molecular basis for functional differences between CK2 and CK2, we have undertaken studies to identify proteins that interact specifically with each isoform of CK2 and could contribute to the regulation of their independent functions. A novel pleckstrin-homology domain containing protein, designated CK2-interacting protein 1 (i.e. CKIP-1) was isolated using the yeast two hybrid system as a protein that interacts with CK2 but not CK2 [23]. When expressed in cells as a fusion with green fluorescent protein, CKIP-1 localizes to the cell membrane and to the nucleus. In this study, we present evidence from deletion analysis of CKIP-1 suggesting that a C-terminal region containing a putative leucine zipper has a role in regulating its nuclear localization. Collectively, our data supports a model whereby CKIP-1 is a non-enzymatic regulator of CK2 that regulates the cellular functions of CK2 by targeting or anchoring CK2 to specific cellular localization or by functioning as an adapter to integrate CK2-mediated signaling events with components of other signal transduction pathways. 相似文献
19.
Summary -Tocopherol was identified in lipid extracts of bovine retinal outer segment (ROS) preparations. Positive identification was obtained by the thin layer chromatographic characteristics of the tocopherol form and its oxidation product -tocopherylquinone, and by the ultraviolet spectrum of the oxidized and KBH4-reduced form of the tocopherylquinone. In the ROS preparations used, -tocopherol chromanol was the predominant species, the quinone form accounting for 25% or less of the total. The concentration of -tocopherol in the ROS preparations was about 0.1 mole -tocopherol per mole rhodopsin, or about 1 nmole/mg, protein. Mitochondria from bovine retina contained about 0.4 nmole -tocopherol per mg protein. 相似文献
20.
Frank Y. T. Sin 《Molecular biology reports》1987,12(2):79-83
The effect of cycloheximide and puromycin on 20-hydroxyecdysone-induced protein synthesis in wing discs of Drosophila melanogaster has been studied by one-dimensional and two-dimensional SDS polyacrylamide electrophoresis. It is found that puromycin, but not cycloheximide, when applied simultaneously with the hormone enhanced the hormone-induced synthesis of the early and late proteins. However, when puromycin was applied after hormone treatment, only the late proteins were induced. The possible implication of these observations is discussed. 相似文献