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41.
Y Hayashi D S Hoon M S Park P I Terasaki L J Foshag D L Morton 《Cellular immunology》1992,139(2):411-425
Human melanoma is an immunogenic neoplasm whereby enhancement of specific cell-mediated immunity can alter tumor progression. HLA-A2-restricted CTL have been demonstrated to kill allogeneic HLA-A2-matched melanoma. We investigated the ability of allogeneic melanoma cells sharing HLA-A antigens to sensitize melanoma patients' lymphocytes to induce HLA-A-restricted CTL to autologous melanoma. PBL from melanoma patients were cocultured with autologous melanoma cells in defined "cocktail medium" to generate melanoma-specific HLA-A-restricted CTL lines. CTL generated by sensitization with allogeneic melanoma bearing shared HLA-A2, A11, A24, or "cross-reactive" HLA-A antigens could kill almost as many autologous melanoma cells as CTL sensitized with autologous melanoma. There are HLA-A antigens that are immunogenically cross-reactive because they share determinant epitopes. CTL were not activated NK or LAK cells. The HLA restriction and melanoma cell specificity of the CTL were demonstrated by cold target inhibition with autologous and allogeneic melanoma and B lymphoblasts. Anti-CD3 and anti-HLA AB inhibited CTL killing of melanoma. The CTL were predominantly CD3+CD4+ TCR alpha/beta+. These studies demonstrate that melanomas being shared or cross-reactive HLA-A can be used for in vitro generation of HLA-restricted CTL that recognize melanoma-associated antigens. The findings have very important implications in human tumor immunotherapy. 相似文献
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Summary The cloning of glucoamylase geneSTA using theSUC2 promoter intoSaccharomyces cerevisiae was performed. The signal sequence ofSTA gene was used for the secretion of glucoamylase protein. The plasmid constructed in this way was named YEpSUCSTA and its expression was identified. The expression of YEpSUCSTA was repressed in the presence of glucose in growth medium, but derepressed when glucose became depleted. YEpSUCSTA showed the similar efficiency of glucoamylase secretion as YEpSTA-F which has the entireSTA gene. Glucoamylase activity in starch-glucose medium was largely increased because cell mass and plasmid stability were high in biosynthesis phase compared to extracellular glucoamylase activities in media which starch or glucose was the only carbon source. 相似文献
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Biofeedback-assisted sexual arousal in females: a comparison of visual and auditory modalities 总被引:1,自引:0,他引:1
E F Hoon 《Biofeedback and self-regulation》1980,5(2):175-191
This study was undertaken to investigate the effects of instructional set and biofeedback modality upon the ability of 23 females to achieve control over sexual arousal. Two levels of instructional set (increase, decrease) were completely crossed with three feedback modalities (audio, visual, no feedback). Changes in vaginal blood volume (VBV) and vaginal pulse amplitude (VPA) were monitored by a vaginal plethysmograph and reduced on line by a microcomputer. During feedback trials, all subjects received audio- or visual feedback of the VBV response. Subjects participated in two sessions, each consisting of six 3-minute trials, one in each instruction/feedback combination. Order of trials was counterbalanced. Subjective levels of arousal, VBV, and VPA were significantly higher under increase instructions. Also, a significant feedback effect was noted in the subjective measure and the VBV measure, favoring visual feedback for overall control of sexual arousal. However, the feedback effect accounted for a small portion of the variance, and it was concluded that performance was not appreciably superior with or without feedback. Thus practical considerations may determine the feedback modality to be used for vaginal vasocongestion in future research. Higher positive correlations of subjective ratings with vaginal blood volume occurred during feedback trials, which suggests that biofeedback may be helpful in discrimination training to facilitate awareness of the feelings associated with different arousal levels and correct labeling of increased vasocongestion as sexual. Further research is necessary to see if sexually dysfunctional women can benefit from a biofeedback component in a comprehensive therapy program and to determine the effect of many training sessions on discrimination and self-control of arousal. 相似文献
46.
Studies on hemoglobin variants in Korean cattle 总被引:1,自引:0,他引:1
814 hemoglobin samples from Korean cattle were investigated by starch gel electrophoresis for the detection of hemoglobin variants. A new variant of cattle hemoglobin, called Hb, H, was recognized. It has a slower rate of migration than Hb A.
Hemoglobin types from 814 Korean cattle were as follows: 652 of Hb AA type (80.1 %), 133 of Hb AB (16.4 %), 12 of Hb AC (1.5 %), 9 of Hb BB (1.1 %), 2 of Hb BC (0.2 %), 4 of Hb AH (0.5 %), 1 of Hb CH (0.1 %), 1 of Hb HH (0.1 %). These figures correspond to the frequencies: HbA = 0.893, HbB = 0.093, Hbc =0.009, HbH = 0.004.
Gene frequencies at the Hb locus in Korean cattle were compared among six population from different provinces. Generally, high frequencies of HbA were observed in each province. 相似文献
Hemoglobin types from 814 Korean cattle were as follows: 652 of Hb AA type (80.1 %), 133 of Hb AB (16.4 %), 12 of Hb AC (1.5 %), 9 of Hb BB (1.1 %), 2 of Hb BC (0.2 %), 4 of Hb AH (0.5 %), 1 of Hb CH (0.1 %), 1 of Hb HH (0.1 %). These figures correspond to the frequencies: Hb
Gene frequencies at the Hb locus in Korean cattle were compared among six population from different provinces. Generally, high frequencies of Hb
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QuangMinh Nguyen Arya Bagus Boedi Iswanto Geon Hui Son Uyen Thi Vuong Jihyun Lee JinHo Kang Walter Gassmann Sang Hee Kim 《Molecular Plant Pathology》2022,23(9):1390
During pathogenesis, effector proteins are secreted from the pathogen to the host plant to provide virulence activity for invasion of the host. However, once the host plant recognizes one of the delivered effectors, effector‐triggered immunity activates a robust immune and hypersensitive response (HR). In planta, the effector AvrRps4 is processed into the N‐terminus (AvrRps4N) and the C‐terminus (AvrRps4C). AvrRps4C is sufficient to trigger HR in turnip and activate AtRRS1/AtRPS4‐mediated immunity in Arabidopsis; on the other hand, AvrRps4N induces HR in lettuce. Furthermore, AvrRps4N‐mediated HR requires a conserved arginine at position 112 (R112), which is also important for full‐length AvrRps4 (AvrRps4F) processing. Here, we show that effector processing and effector recognition in lettuce are uncoupled for the AvrRps4 family. In addition, we compared effector recognition by lettuce of AvrRps4 and its homologues, HopK1 and XopO. Interestingly, unlike for AvrRps4 and HopK1, mutation of the conserved R111 in XopO by itself was insufficient to abolish recognition. The combination of amino acid substitutions arginine 111 to leucine with glutamate 114 to lysine abolished the XopO‐mediated HR, suggesting that AvrRps4 family members have distinct structural requirements for perception by lettuce. Together, our results provide an insight into the processing and recognition of AvrRps4 and its homologues. 相似文献
49.
Soyoung Kim Jaeseok Han Young-Ho Ahn Chang Hoon Ha Jung Jin Hwang Sang-Eun Lee Jae-Joong Kim Nayoung Kim 《Molecules and cells》2022,45(6):403
Hypoxia leads to significant cellular stress that has diverse pathological consequences such as cardiovascular diseases and cancers. MicroRNAs (miRNAs) are one of regulators of the adaptive pathway in hypoxia. We identified a hypoxia-induced miRNA, miR-34c, that was significantly upregulated in hypoxic human umbilical cord vein endothelial cells (HUVECs) and in murine blood vessels on day 3 of hindlimb ischemia (HLI). miR-34c directly inhibited BCL2 expression, acting as a toggle switch between apoptosis and autophagy in vitro and in vivo. BCL2 repression by miR-34c activated autophagy, which was evaluated by the expression of LC3-II. Overexpression of miR-34c inhibited apoptosis in HUVEC as well as in a murine model of HLI, and increased cell viability in HUVEC. Importantly, the number of viable cells in the blood vessels following HLI was increased by miR-34c overexpression. Collectively, our findings show that miR-34c plays a protective role in hypoxia, suggesting a novel therapeutic target for hypoxic and ischemic diseases in the blood vessels. 相似文献
50.
Unique crystal-originated pit (COP) distribution, similar to a striation pattern, is well matched with the oxygen profile in experimental analysis. It shows the strong relationship between oxygen concentration and COP distribution. In this paper, we study the generation of void defects and the relationship between interstitial oxygen and vacancy using the kinetic lattice Monte Carlo (KLMC) method. The KLMC method has been applied extensively in various forms to the study of micro-defects in silicon wafers. It explained well the formation of void defects such as vacancy–oxygen complex and vacancy–vacancy complex. The formation of clusters is strongly affected by oxygen concentration, which showed the relationship between COP distribution and oxygen concentration. The unique COP distribution could be correctly explained with KLMC results, and this kind of meso-scale results has not yet been reported. 相似文献