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1.
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   
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Ten patients with advanced progressive adenocarcinoma of the prostate were treated with a long acting analogue of gonadotrophin releasing hormone. Eight of these patients responded to treatment in terms of pain relief and clinical regression of tumour. Serum gonadotrophin and testosterone concentrations were significantly suppressed by the end of the second week of treatment, testosterone concentrations being comparable with those achieved by castration. The two patients who failed to respond had both relapsed previously when receiving conventional treatment, and neither showed any endocrine response to the analogue. Superagonists of gonadotrophin releasing hormone may be the treatment of choice in adenocarcinoma of the prostate, but further trials are required to establish long term safety and efficacy.  相似文献   
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The time dependency of the spontaneous aggregation of the fibrillogenic β-Amyloid peptide, Aβ1–40, was measured by turbidity, circular dichroism, HPLC, and fluorescence polarization. The results by all methods were comparable and they were most consistent with a kinetic model where the peptide first slowly forms an activated monomeric derivative (AM), which is the only species able to initiate, by tetramerization, the formation of linear aggregates. The anti-Aβ antibody 6E10, raised against residues 1–17, at concentrations of 200–300 nM delayed significantly the aggregation of 50 μM amyloid peptide. The anti–Aβ antibody 4G8, raised against residues 17–24, was much less active in that respect, while the antibody A162, raised against the C-terminal residues 39–43 of the full-length Aβ was totally inactive at those concentrations. Concomitant with the aggregation experiments, we also measured the time dependency of the Aβ1–40–induced toxicity toward SH-EP1 cells and hippocampal neurons, evaluated by SYTOX Green fluorescence, lactate dehydrogenase release, and activation of caspases. The extent of cell damage measured by all methods reached a maximum at the same time and this maximum coincided with that of the concentration of AM. According to the kinetic scheme, the latter is the only transient peptide species whose concentration passes through a maximum. Thus, it appears that the toxic species of Aβ1–40 is most likely the same transient activated monomer that is responsible for the nucleation of fibril formation. These conclusions should provide a structural basis for understanding the toxicity of Aβ1–40 in vitro and possibly in vivo.  相似文献   
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Ultrastructure of dormant and germinating conidia of Aspergillus nidulans   总被引:2,自引:0,他引:2  
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Harbor seal ( Phoca vitulina ) haul-out site use may be affected by natural or anthropogenic factors. Here, we use an 11-yr (1997–2007) study of a seal colony located near a mariculture operation in Drakes Estero, California, to test for natural (El Niño-Southern Oscillation (ENSO), density-dependence, long-term trends) and anthropogenic (disturbance or displacement related to oyster production activities) factors that may influence the use of haul-out subsites. Annual mariculture related seal disturbance rates increased significantly with increases in oyster harvest ( r s= 0.55). Using generalized linear models (GLMs) ranked by best fit and Akaike's Information Criteria, ENSO and oyster production (as a proxy for disturbance/displacement) best explained the patterns of seal use at all three subsites near the mariculture operations, with effects being stronger at the two subsites closest to operations. Conversely, density-dependence and linear trend effects poorly explained the counts at these subsites. We conclude that a combination of ENSO and mariculture activities best explain the patterns of seal haul-out use during the breeding/pupping season at the seal haul-out sites closest to oyster activities.  相似文献   
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In this study, 18 partly commercially available samples of rock salt from Austria, Germany, Pakistan, Poland, Switzerland, and Ukraine were investigated with respect to their content of trace elements using instrumental neutron activation analysis. Elements detected were Al, Ba, Br, Ca, Ce, Cl, Co, Cr, Cs, Eu, Fe, Hf, La, Mn, Na, Rb, Sb, Sc, Sm, Sr, Ta, Tb, Th, and Zn, some of them only in individual cases. An estimation of the bioavailability of these trace elements was performed by dissolving an equivalent of the sodium chloride samples in diluted hydrochloric acid (simulating stomach acid), filtering off the insoluble components, and analyzing the evaporated filtrate. It could be shown that in most cases bioactive trace elements like Fe can be found in rock salt in the form of almost insoluble compounds and are therefore not significantly bioavailable, whereas thorium, for example, was partly bioavailable in two cases. A significant contribution to the recommended daily intake of metal trace elements by using rock salt for nutrition can be excluded.  相似文献   
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Semiempirical and ab initio theoretical methods have been used to investigate molecular structures of the chalcogen-substituted carboxylic acid isomers RC(=O)XH (chalcogenol acid) and RC(=X)OH (chalcogenon acid). A recent experimental report suggests that the chalcogenon isomers, although less stable at room temperature, predominate at low temperature in polar solvents and that there is only a small barrier to isomerization between the isomers. Theoretical calculations have been used to locate minimum energy structures of chalcogen-substituted carboxylic acid isomers and to calculate energy differences between pairs of isomers. Carboxylic acids are well known to dimerize, especially in the gas phase and in non-polar solvents. We have, therefore, also calculated energies of dimerization of the chalcogen-substituted acids by optimizing the geometries of the symmetric dimers. We note that the PM3 level of theory is only qualitatively correct for sulfur- and selenium-containing species but fails even qualitatively for the tellurium-containing compounds. Ab initio results confirm the experimental observations and provide good estimates of both isomerization and dimerization energies. We conclude that for many functional groups with tautomers RC(=X)YH and RC(=Y)XH, the more acidic tautomer is the one with the acid proton on the smaller, more electronegative atom, although in many cases this may not be the more stable tautomer.Electronic Supplementary Material available.  相似文献   
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