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991.
Marek Zembala Antoni Czupryna Jerzy Wieckiewicz Marek Jasinski Juliusz Pryjma Irena Ruggiero Maciej Siedlar Tadeusz Popiela 《Cancer immunology, immunotherapy : CII》1993,36(2):127-132
Summary Human peripheral blood monocytes cocultured with tumour cells were used as an in vitro model of in situ interactions between tumour-infiltrating macrophages and the tumour. Tumour cells stimulated de novo expression of the human tumour necrosis factor (TNF) gene in monocytes and caused the release of TNF into the culture supernatant. A group of 14 patients with stage IVA gastric cancer receiving adjuvant chemotherapy (5-FU, Adriamycin, mitomycin C: FAM) or immunochemotherapy (BCG+FAM) was investigated for the ability of monocytes to produce TNF in vitro upon stimulation with tumour cells or purified protein derivative of tuberculin (PPD). Patients were followed at biweekly intervals, i.e. before each instillation of BCG epicutaneously over a period of 10 weeks. It was found that monocytes of some patients receiving BCG at the end of the observation period had an enhanced ability to produce TNF following stimulation with tumour cells. In contrast, such production was not substantially altered during the study period in patients on chemotherapy. PPD-induced TNF production was much weaker and was not significantly changed during this observation time. We infer that BCG immunotherapy may induce the subtle changes in some cancer patients that lead to an increased interaction between monocytes and tumour cells and result in enhanced production of cytokine(s) with antitumour properties. 相似文献
992.
M. Stoeck C. Marland-Noske M. Manasterski R. Zawatzky S. Horn V. Möbus P. Schlag V. Schirrmacher 《Cancer immunology, immunotherapy : CII》1993,37(4):240-244
In order to understand further the effects of Newcastle-disease-virus(NDV)-modified tumour vaccines we investigated the feasibility of isolating lymphocytes from the site of injection of patients undergoing postoperative active specific immunization (ASI) with autologous NDV-modified tumour cells. Delayed-type-hypersensitivity(DTH)-like reactions from five cancer patients were surgically removed, minced and the tissue particles were digested with collagenase and DNase. Lymphoid cells recovered were expanded in a highly efficient limiting-dilution analysis system optimized for T cell growth [Moretta et al. (1983) J Exp Med 157: 743] and lymphocyte microcultures (clonal probability >0.8) could be grown for up to 1 year. Analysis of the microcultures for phenotype and function showed that the majority were positive for CD4 (92%) and TCR (96%). Concanavalin-A-induced production of interleukin-2 (IL-2), IL-6, interferon and tumour necrosis factor was detected in more than 70% of the microcultures. Lectin-dependent cytotoxicity was only very rarely observed. The general characteristics of the microcultures obtained support the notion of a DTH-like reaction taking place at the site of tumour cell challenge. The possibility of in vitro expansion and cultivation of T lymphocytes from ASI vaccination sites should help to elucidate further the role of these cells in active specific immunization against autologous tumour cells.This study was supported by Dr.-Mildred-Scheel-Stiftung and the Tumorzentrum Heidelberg 相似文献
993.
I. Alvarez M. Sans R. Toledo M. Sosa M. Bengochea F. M. Salzano 《International Journal of Anthropology》1993,8(3):163-168
A total of 604 individuals living in Montevideo and other places in Uruguay were studied in relation to three I HLA loci.
The most common alleles observed (percentages in parentheses) were A2(24), A9(15), A19(11), B12(12), B35(12), and C4(16).
The most marked departures from linkage equilibrium (all numbers multiplied by 105) were B35-C4(636), A2-B5(590), A2C3(515), A2B14(494), and A19-B12(485). These findings do not contradict the hypothesis that
while most of the Uruguayan population is of Caucasoid origin, significant African and Amerindian genes may exist in its gene
pool. 相似文献
994.
A number of Ca2+-, K+-, and Na+-channel modulators has been tested with respect to their effects on [3H]tyramine (TY) binding, as a putative marker for the vesicular dopamine (DA) transporter in striatal membrane preparations containing vesicle ghosts. Among organic Ca2+-channel modulators, the diphenylalkylamines tested consistently inhibited TY binding: the order of potency was prenylamine>lidoflazine>flunarizine>cinnarizine, with Ki values of 0.1, 0.2, 0.5 and 1.2 M, respectively. Low (up to 100 nM) concentrations of prenylamine did competitively inhibit TY binding, and higher concentrations provoked a mixed-type inhibition. Furthermore, LIGAND-analysis of competition curves revealed a high- and a low-affinity binding site for prenylamine and flunarizine. The TY binding process was also sensitive to selected K+- and Na+-channel modulators. Since several Ca2+-antagonists are known to affect H+-ATPase and the bioenergetics of catecholamine storage vesicles in chromaffin granules, thus affecting monoamine storage, the energy requirements for the formation of the TY/carrier complex were here assessed, assuming similarity between chromaffin granules and synaptic vesicles. TY binding, though not reflecting endovesicle-sequestered TY, was indeed strongly sensitive (with Ki coefficients in the fM or low nM range) to the dissipation of the vesicular transmembrane proton concentration ( pH), electrical ( ), and proton electrochemical ( H+) gradients, provoked by a number of specifically targeted agents. It is concluded that Ca2+-channel agents of the diphenylalkylamine group may directly affect striatal TY binding due to an extrachannel-regulated competition with TY for the vesicular carrier of DA, as well indirectly, by disruption of the transmembrane energization of the reserpine-sensitive carrier. 相似文献
995.
M. D. H. M. William A. Mujeeb-Kazi 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1993,86(2-3):365-370
Summary
Thinopyrum bessarabicum (2n = 2x = 14, JJ) with its unique property of salt tolerance provides a potential means for the transfer of this important and complex trait into cultivated wheat through intergeneric hybridization. To accomplish this, diagnostic markers for detecting the presence of Th. bessarabicum chromosomes in a wheat background have to be established. The C-banded karyotype of Th. bessarabicum distinctly identifies individual Th. bessarabicum chromosomes and separates them from those of Triticum aestivum. Also, seven protein/isozymes, i.e., malate dehydrogenase, high-molecular-weight glutenin, Superoxide dismutase, grain esterase, glutamate oxaloacetate transaminase, -amylase and -amylase, were identified as being positive markers specific to Th. bessarabicum; these were also expressed in the T. aestivum/Th. bessarabicum amphiploid. These diagnostic biochemical markers could be useful in detecting and establishing homoeology of Th. bessarabicum chromosomes in T. aestivum/Th. bessarabicum intergeneric hybrid derivatives. 相似文献
996.
I. Hoeschele P. M. VanRaden 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1993,85(8):946-952
Summary A Bayesian method was developed for identifying genetic markers linked to quantitative trait loci (QTL) by analyzing data from daughter or granddaughter designs and single markers or marker pairs. Traditional methods may yield unrealistic results because linkage tests depend on number of markers and QTL gene effects associated with selected markers are overestimated. The Bayesian or posterior probability of linkage combines information from a daughter or granddaughter design with the prior probability of linkage between a marker locus and a QTL. If the posterior probability exceeds a certain quantity, linkage is declared. Upon linkage acceptance, Bayesian estimates of marker-QTL recombination rate and QTL gene effects and frequencies are obtained. The Bayesian estimates of QTL gene effects account for different amounts of information by shrinking information from data toward the mean or mode of a prior exponential distribution of gene effects. Computation of the Bayesian analysis is feasible. Exact results are given for biallelic QTL, and extensions to multiallelic QTL are suggested. 相似文献
997.
D. J. Mackill M. A. Salam Z. Y. Wang S. D. Tanksley 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1993,85(5):536-540
Summary Photoperiod-sensitive rice (Oryza sativa L.) cultivars are widely grown in rainfed lowland areas with unfavorable water regimes. A molecular marker for the trait would be useful in genetic and physiological studies and in developing improved photoperiod-sensitive cultivars. Previous genetic studies identified a major gene for photoperiod sensitivity on chromosome 6. We have tested an isozyme marker and several RFLP probes mapping to chromosome 6 in an attempt to identify marker(s) tightly linked to photoperiod sensitivity in tropical rice cultivars. We report here that the isozyme gene Pgi-2 is linked (23.2±4.7 cM) to the photoperiod-sensitivity gene in the cultivar GEB-24. Although association of duration with Pgi-2 alleles can be used to detect segregation of the photoperiod sensitivity gene in crosses, it will probably not be useful as a marker in selection because of its loose linkage. In contrast, a gene for photoperiod sensitivity in the cultivar Puang Rai 2 was found to be closely linked to the rice genomic clone RG64. Among 15 F3 lines homozygous for photoperiod insensitivity, no recombinants were detected with RG64. This clone is thus an excellent probe to follow segregation of the major photoperiod-sensitivity gene in rice crosses. 相似文献
998.
D. Menancio-Hautea C. A. Fatokun L. Kumar D. Danesh N. D. Young 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1993,86(7):797-810
Genome relationships between mungbean (Vigna tradiata) and cowpea (V. Unguiculata) based on the linkage arrangement of random genomic restriction fragment length polymorphism (RFLP) markers have been investigated. A common set of probes derived from cowpea, common bean (Phaseolus vulgaris), mungbean, and soybean (Glycine max) PstI genomic libraries were used to construct the genetic linkage maps. In both species, a single F2 population from a cross between an improved cultivar and a putative wild progenitor species was used to follow the segregation of the RFLP markers. Approximately 90% of the probes hybridized to both mungbean and cowpea DNA, indicating a high degree of similarity in the nucleotide sequences among these species. A higher level of polymorphism was detected in the mungbean population (75.7%) than in the cowpea population (41.2%). Loci exhibiting duplications, null phenotypes, and distorted segregation ratios were detected in both populations. Random genomic DNA RFLP loci account for about 89% of the currently mapped markers with a few cDNA and RAPD markers added. The current mungbean map is comprised of 171 loci/loci clusters distributed in 14 linkage groups spanning a total of 1570cM. On the other hand, 97 markers covered 684 cM and defined 10 linkage groups in the current cowpea map. The mungbean and cowpea genomes were compared on the basis of the copy number and linkage arrangement of 53 markers mapped in common between the two species. Results indicate that nucleotide sequences are conserved, but variation in copy number were detected and several rearrangements in linkage orders appeared to have occurred since the divergence of the two species. Entire linkage groups were not conserved, but several large linkage blocks were maintained in both genomes. 相似文献
999.
M. S. Davidoff W. Schulze R. Middendorff A. -F. Holstein 《Cell and tissue research》1993,271(3):429-439
A number of marker substances for neuronal and neuroendocrine cells have been demonstrated in the cytoplasm of the interstitial
Leydig cells of human testes using basic immunocytochemical methods and some of their modifications. We were able to reveal
immunoreactivity for enzymes involved in the synthesis of the catecholamines dopamine and noradrenaline (tryosine hydroxylase,
aromatic L-amino acid decarboxylase, dopamine-β-hydroxylase), for the indolamine 5-hydroxytryptamine (serotonin), as well
as for a number of wellknown neuronal markers such as the neurofilament protein 200, synaptophysin, chromogranin A+B, the
neural cell-adhesion molecule (N-CAM), the microtubule-associated protein (MAP-2), and the calcium-binding proteins: S-100,
calbindin and parvalbumin. Immunoreactivity for these substances was found in the majority of the interstitial cells although
differences in the staining intensity among the individual Leydig cells and among Leydig cells from different patients were
observed. At the electron-microscopic level the Leydig cell cytoplasm was seen to contain microtubules, intermediate- and
microfilaments as well as clear (40–60 nm) and dense-core (100–300 nm) vesicles, providing a morphological correlate for some
of the immunocytochemical results. Although individual marker substances are not absolutely specific for nerve and neuroendocrine
cells, the results obtained, together with the already established neuronspecific enolase-, substance P-, methionine-enkephalinand
proopiomelanocortin (POMC)-derived peptide-like immunoreactivity, provide strong evidence for the neuroendocrine (paraneuronal,
APUD-like) nature of the Leydig cells of the human testis.
Dedicated to Professor Dr. Werner Hilscher on the occasion of this 65th birthday 相似文献
1000.
TAI系列Ⅰ中的冰草染色体与小麦部分同源关系的同工酶研究 总被引:1,自引:1,他引:0
本文分析了TAI系列Ⅰ及其亲本的胚乳过氧化物酶(CPXE)、苹果酸脱氢酶(MDH)、醇脱氢酶(ADH)、酸性磷酸酶(ACPH)和碱性磷酸酶(PHE)的酶谱表型。把冰草同工酶结构基因Mdh-Ag~t2定位到TAI-13、基因Cpxe-Ag~2定位到TAI-14、基因Adh-Ag~t1、Acph-Ag~t2和Phe-Ag~t2定位到TAI-16中的冰草染色体上。根据这些基因定位和我们以前的研究工作,结合植株表型分析,推测TAI-11、TAI-12、TAI-13、TAI-14、TAI-15、TAI-16和TAI-17中的冰草染色体分别与小麦第2、3、1、7、6、4和5同祖群有一定部分同源关系。 相似文献