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A major challenge for successful immunotherapy against glioma is the identification and characterization of validated targets. We have taken a bioinformatics approach towards understanding the biological context of IL-13 receptor α2 (IL13Rα2) expression in brain tumors, and its functional significance for patient survival. Querying multiple gene expression databases, we show that IL13Rα2 expression increases with glioma malignancy grade, and expression for high-grade tumors is bimodal, with approximately 58% of WHO grade IV gliomas over-expressing this receptor. By several measures, IL13Rα2 expression in patient samples and low-passage primary glioma lines most consistently correlates with the expression of signature genes defining mesenchymal subclass tumors and negatively correlates with proneural signature genes as defined by two studies. Positive associations were also noted with proliferative signature genes, whereas no consistent associations were found with either classical or neural signature genes. Probing the potential functional consequences of this mesenchymal association through IPA analysis suggests that IL13Rα2 expression is associated with activation of proinflammatory and immune pathways characteristic of mesenchymal subclass tumors. In addition, survival analyses indicate that IL13Rα2 over-expression is associated with poor patient prognosis, a single gene correlation ranking IL13Rα2 in the top ~1% of total gene expression probes with regard to survival association with WHO IV gliomas. This study better defines the functional consequences of IL13Rα2 expression by demonstrating association with mesenchymal signature gene expression and poor patient prognosis. It thus highlights the utility of IL13Rα2 as a therapeutic target, and helps define patient populations most likely to respond to immunotherapy in present and future clinical trials.  相似文献   
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(S)-(-)-Tropic acid is the acidic moiety of the tropane ester alkaloids, hyoscyamine and scopolamine (hyoscine). When tropic acid is fed to transformed root cultures of Datura stramonium L. or a Brugmansia (Datura) Candida x B. aurea hybrid, the formation of these alkaloids is inhibited. Phenyllactic acid, from which the tropoyl moiety is derived, is considerably less inhibitory. Label from (RS)-phenyl[1,3-13C2]lactic acid is incorporated at high levels into apoatropine, littorine, aposcopolamine, hyoscyamine, 7-hydroxyapoatropine, scopolamine and 7-hydroxyhyoscyamine when fed to these cultures. The presence of an excess concentration of unlabelled tropic acid has little influence on the specific incorporation into these products. It is concluded that free tropic acid is not an intermediate in hyoscyamine biosynthesis but rather that the rearrangement of phenyllactic acid occurs subsequent to its esterification.Abbreviations FM fresh mass - NMR nuclear magnetic resonance spectroscopy We are grateful to Drs. N.J. Walton, A.J. Parr, M.J.C. Rhodes (Institue of Food Research, Norwich) and B. Dräger (Münster, Germany) for helpful and critical discussions. We also wish to thank Dr. P. Bachmann (Braunschweig, Germany) for suggesting the use of the DB-17 column to separate littorine from hyoscyamine and for the modified Excel programme used to calculate the specific incorporations, Yannick Ford (AFRC Co-operative Award Studentship, University of Oxford) and Abigael Peerless for their able assistance, Dr. I. Colquhoun for assistance with some of the NMR spectroscopy and Drs. K. Shimomura (Tsukuba, Japan) and T. Hashimoto (Kyoto, Japan) for pure samples of 7-hydroxyhyoscyamine. J.G.W, gratefully acknowledges support from the Nuffield Foundation under the Small Grants Scheme to promote collaborative experimentation and M.A. is grateful to the Ministry of Education, Iran for a research scholarship.  相似文献   
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In the fowl the primordial germ cells accumulate in the germinal crescent to the anterior of the two-day embryo. A simple ballistic device has been used to fire tungsten particles (mean diameter 1.5 m) into this region. By coating these projectiles with vector DNA it is possible to transfect these cells. Hatchlings produced by this technique were raised to sexual maturity and shown to contain the foreign DNA in their sperm. G1 offspring containing this DNA were also produced in roughly 20% of these cockerels. In the majority of cases the vector DNA disappeared from the G1 generation as they matured suggesting that in these cases it had been transmitted episomally.  相似文献   
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Sensitization to psychostimulant drugs, as well as morphine, subjected to cross-sensitization with stress. The development of morphine sensitization is associated with enhancements in dopamine overflow in the Nucleus accumbens (NAc). This study aimed to examine the role of accumbal D1/D2-like dopamine receptors in restraint stress (RS) induced sensitization to morphine antinociceptive effects. Adult male Wistar rats weighing 220–250 g underwent stereotaxic surgery. Two stainless steel guide cannulae were bilaterally implanted, 1 mm above the NAc injection site. Different solutions of SCH-23390, as a D1-like receptor antagonist or sulpiride, as a D2-like receptor antagonist, were microinjected into the NAc five min before exposure to RS. Restraint stress lasted for 3 h, 10 min after RS termination; animals received a subcutaneous injection of morphine (1 mg/kg) for 3 consecutive days. The procedure was followed by a 5-day drug and/or stress-free period. After that, on the 9th day, the nociceptive response was evaluated by the tail-flick test. The results revealed that intra-NAc administration of D1/D2-like dopamine receptor antagonists, SCH-23390 or sulpiride, respectively, blocked morphine sensitization-induced by RS and morphine co-administration in rats for three consecutive days. This work provides new insight into the determinant role of accumbal dopamine receptors in morphine sensitization produced by RS-morphine co-administration.

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Biodiversity and Conservation - Palaeoecology is increasingly contributing to conservation biology and restoration ecology by extending the recent annual to decennial records of ecological...  相似文献   
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Biochemical Genetics - Several studies have noted that vitamin D receptor (VDR) gene polymorphisms are involved in the susceptibility to Coronary artery disease (CAD). Nonetheless, the results have...  相似文献   
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Medicinal plants play important role in industrial production of medicines. Moreover, they consume without complicated processes around the world. They are considered as healthy cure without any harmful side effects at least among ordinary people. Cold stress is one the harmful abiotic stresses and constrains medicinal plants yielding geographically. Cold acclimation is a process that induces cold stress resistance in temperate plants. Various structural and morphological alterations are involved in this process. Also, enzymatic and non-enzymatic agents play role in cold acclimation. Cell membrane modification and compatible solutes accumulation and so many other changes occur through cold acclimation. Growing under different stressful conditions, medicinal plants synthesize different components such as metabolites. Moreover, ROS can be generated in plant cells under stressful conditions. The accumulation of bioactive components, biosynthesis of phytohormones, ion hemostasis, osmolyte (compatible solutes) accumulation and changes in nutrient uptake, root system modification and systemic resistance are some of new investigations that are considered in this review.  相似文献   
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International Journal of Peptide Research and Therapeutics - Appetite is controlled by a complex system of central and peripheral signals interacting to modulate the ingestion response. Several...  相似文献   
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International Journal of Peptide Research and Therapeutics - RFamide-related Peptide-3(RFRP-3) plays a key role in appetite regulation. The current study aimed to determine the effect of...  相似文献   
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