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1.
Minh C. Nguyen Guang Huan Tu Kathryn E. Koprivnikar Melissa Gonzalez-Edick Karin U. Jooss Thomas C. Harding 《Cancer immunology, immunotherapy : CII》2010,59(9):1313-1323
A critical factor in clinical development of cancer immunotherapies is the identification of tumor-associated antigens that
may be related to immunotherapy potency. In this study, protein microarrays containing >8,000 human proteins were screened
with serum from prostate cancer patients (N = 13) before and after treatment with a granulocyte–macrophage colony-stimulating factor (GM-CSF)-secreting whole cell immunotherapy.
Thirty-three proteins were identified that displayed significantly elevated (P ≤ 0.05) signals in post-treatment samples, including three proteins that have previously been associated with prostate carcinogenesis,
galectin-8, T-cell alternative reading frame protein (TARP) and TNF-receptor-associated protein 1 (TRAP1). Expanded analysis
of antibody induction in metastatic, castration-resistant prostate cancer (mCRPC) patients (N = 92) from two phase 1/2 trials of prostate cancer immunotherapy, G-9803 and G-0010, indicated a significant (P = 0.03) association of TARP antibody induction and median survival time (MST). Antibody induction to TARP was also significantly
correlated (P = 0.036) with an increase in prostate-specific antigen doubling time (PSADT) in patients with a biochemical (PSA) recurrence
following prostatectomy or radiation therapy (N = 19) from in a previous phase 1/2 trial of prostate cancer immunotherapy, G-9802. RNA and protein encoding TARP and TRAP1
was up-regulated in prostate cancer tissue compared to matched normal controls. These preliminary findings suggest that antibody
induction to TARP may represent a possible biomarker for treatment response to GM-CSF secreting cellular immunotherapy in
prostate cancer patients and demonstrates the utility of using protein microarrays for the high-throughput screening of patient-derived
antibody responses. 相似文献
2.
In human hepatoma cell line Hep3B/T2, the human heat-shock-inducible gene hsp70 could be induced by insulin. The dose-dependent insulin effect correlates very well with the dissociation constant of the insulin receptor, indicating that the insulin effect is mediated by the insulin receptor. The expression of hsp70 gene was neither significantly induced by growth factors of epidermal and platelet-derived growth factors, nor by tumor promoter, calcium ionophore, cAMP, and glucocorticoids. These results indicate that the induction of expression of hsp70 gene by insulin is very specific and not cell cycle-related. Furthermore, the insulin-induced expression of hsp70 gene is transient, occurring specifically from 4 to 8 h after insulin addition. 相似文献
3.
S Y Yan Z R Mao H Y Yang M A Tu S H Li G P Huang G S Li L Guo G Q Jin R F He 《The International journal of developmental biology》1991,35(4):429-435
The nucleus of a blastula cell from Tilapia (Oreochromis nilotica, family Cichlidae, order Perciformes) was transplanted into an enucleated egg of Loach (Paramisgurnus dabryanus, family Cobitidae, order Cypriniformes). From among 3747 nucleo-cytoplasmic hybrid (NCH) eggs two NCH larval fish (0.05%) were obtained; one died on the 6th day and the other died on the 12th day after the operation. Morphological examinations showed that both NCH larval fish had developed normally with an opened mouth except they could not take food after complete utilization of their egg yolk on the 5th day of development. The possible mechanisms for obtaining such inter-order NCH larval fish are discussed. This is the first report indicating that inter-order NCH larval fish can be obtained in spite of their evolutionary divergence. 相似文献
4.
Studies of electron-transfer properties of salicylate hydroxylase from Pseudomonas cepacia and effects of salicylate and benzoate binding 总被引:1,自引:0,他引:1
The pH dependence of the redox behavior of salicylate hydroxylase from Pseudomonas cepacia as well as the effects of salicylate, benzoate, and chloride binding is described. At pH 7.6 in 0.02 M potassium phosphate buffer E1(0')(EFl ox/EFl.-) is -0.150 V and E2(0')(EFl.-/EFl red H-) is -0.040 V versus the standard hydrogen electrode (SHE). A maximum of 5% of FAD anion semiquinone is thermodynamically stabilized under these conditions. However, in coulometric and dithionite titrations more semiquinone is kinetically formed, indicating slow transfer of the second electron. The potential/pH dependence is consistent with a two-electron, one-proton transfer. Upon salicylate binding the midpoint potential is shifted 0.020 V negative from -0.094 to -0.114 V vs SHE at pH 7.6. A maximum of 7% of the neutral semiquinone is stabilized both in potentiometric and coulometric titrations. This small potential shift indicates that the substrate is bound nearly to the same extent to all three oxidation states of the enzyme. It is clear that the substrate binding does not make the reduction of the flavin thermodynamically more favorable. In contrast to salicylate, the potential shift caused by the effector, benzoate, is much more significant. (A maximum potential shift of -0.07 V is calculated.) Benzoate binds most tightly to the oxidized form and is least tightly bound to the two-electron-reduced form of the enzyme. For the reduction of the free enzyme the transfer of the second electron or the transfer of the proton is rate limiting, as is shown by the kinetic formation of the anionic semiquinone.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
5.
Tissue-specific expression of the rat glutathione S-transferases 总被引:9,自引:0,他引:9
Tissue-specific patterns of rat glutathione S-transferase expression have been demonstrated by in vitro translation of purified poly(A) RNAs and by protein purification. Poly(A) RNAs from six rat tissues including heart, kidney, liver, lung, spleen, and testis were used to program in vitro translation with the rabbit reticulocyte lysate system and [35S]methionine. The glutathione S-transferase subunits synthesized in vitro were purified from the translation products by affinity chromatography on S-hexylglutathione-linked Sepharose 6B columns. The affinity bound fractions were analyzed by Na dodecyl SO4-polyacrylamide gel electrophoresis and fluorography. A subunit of Mr = 22,000 detected in the in vitro translation products of poly(A) RNAs from heart, kidney, lung, spleen, and testis is missing from the translation products of liver poly(A) RNAs. This Mr = 22,000 subunit is present only in the anionic glutathione S-transferase fraction purified from rat heart, kidney, lung, spleen, and testis. Purified anionic glutathione S-transferase from rat liver does not contain this subunit. The relative specific activities toward a dozen different substrates also demonstrate the nonidentity between liver and kidney anionic glutathione S-transferases. In addition, among the glutathione S-transferase subunits expressed in the liver, some of them could not be detected in the other tissues investigated. Our results indicate that tissue-specific expression of rat glutathione S-transferases may occur pretranslationally. 相似文献
6.
7.
The prokaryotic Synechococcus sp. RF-1 exhibited a nitrogen fixation circadian rhythm with characteristics remarkably similar to the circadian rhythm of eukaryotes. The rhythm had a free-running period of about 24 hours when the length of the preen-trained cycle did not differ too much from 24 hours, and it was insensitive to changes in temperature from 22°C to 33°C. Because the endogenous rhythm of nitrogen fixation was not affected by a phase-shift of its previous cycles, the circadian rhythm in Synechococcus sp. RF-1 was not considered to be controlled simply by a feedback mechanism. 相似文献
8.
Sugar analogs were used to study the inhibition of cell wall-associated glycosidases in vitro and in vivo. For in vitro characterization, cell walls were highly purified from corn (Zea mays L.) root cortical cells and methods were developed to assay enzyme activity in situ. Inhibitor dependence curves, mode of inhibition, and specificity were determined for three sugar analogs. At low concentrations of castanospermine (CAS), 2-acetamido-1,5-imino-1,2,5-trideoxy-d-glucitol, and swainsonine, these inhibitors showed competitive inhibition kinetics with β-glucosidase, β-GIcNAcase, and α-mannosidase, respectively. Swainsonine specifically inhibited α-mannosidase activity, and 2-acetamido-1,5-imino-1,2,5-trideoxy-d-glucitol specifically inhibited β-N-acetyl-hexosamindase activity. However, CAS inhibited a broad spectrum of cell wall-associated enzymes. When the sugar analogs were applied to 2 day old corn seedlings, only CAS caused considerable changes in root growth and development. To ensure that the concentration of inhibitors used in vitro also inhibited enzyme activity in vivo, an in vivo method for measuring cell wall-associated activity was devised. 相似文献
9.
“引黄济青”输水沿线水生生物分布与蓄水库富营养化关系的研究 总被引:3,自引:0,他引:3
“引黄济青”是国家“七五”重点工程,由黄河下游博兴县境内打渔张闸引水,在渠首沉沙后,再经惠民、东营、潍坊和青岛的10个县区约253km的明渠输送,到达唠山县棘洪滩蓄水库蓄存,实现向青岛市日供水3.0×10~5m~3。明渠输水过程中,来白沿线的营养物质会污染水体,加之输水在库中滞留时间长,会不会发生富营养化,这是社会普遍关注的问题。 相似文献
10.
William R. Kem Chiang-Kuang Tu Robert W. Williams Arazdordi Toumadje W. Curtis Johnson Jr. 《The protein journal》1990,9(4):433-443
The secondary structure ofCerebratulus lacteus toxin B-IV, a neurotoxic polypeptide containing 55 amino acid residues and four disulfide bonds, was experimentally estimated by computer analyses of toxin circular dichroism (CD) and laser Raman spectra. The CD spectrum of the toxin displayed typical α-helical peaks at 191, 208, and 222 nm. At neutralpH, the α-helix estimates from CD varied between 49 and 55%, when nonrepresentative spectrum analytical methods were used. Analysis of the laser Raman spectrum obtained at a much higher toxin concentration yielded a 78% α-helix estimate. Both CD and Raman spectroscopic methods failed to detect any β-sheet structure. The spectroscopic analyses revealed significantly more α-helix and less β-sheet for toxin B-IV than was predicted from its sequence. To account for the difference between the 49–55% helix estimate from CD spectra and the 78% helix estimate from the Raman spectrum, we postulate that some terminal residues are unfolded at the low toxin concentrations used for CD measurements but form helix at the high toxin concentration used for Raman measurements. Our CD observations showing thatCerebatulus toxin B-IV helix content increases about 15% in trifluoroethanol or at highpH are consistent with this interpretation. 相似文献