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81.
In situ hybridization histochemistry with somatostatin sst1-sst5 receptor messenger RNA-selective oligoprobes and quantitative receptor autoradiographic binding studies using [125I]Tyr3-octreotide, [Leu2,D-Trp22,125I-Tyr25]somatostatin-28 and [125I]CGP 23996 ([125I]c[Asn-Lys-Asn-Phe-Phe-Trp-Lys-Thr-Tyr-Thr-Ser]) were performed to determine the level of expression of somatostatin receptor messenger RNA and receptor binding sites in the hippocampal formation, limbic system and cerebral cortex of adult rats electrically kindled in the dorsal hippocampus. In control rats (implanted with electrodes but not electrically stimulated), the somatostatin-1 receptor-selective [125I]Tyr3-octreotide and the non-subtype-selective [Leu3,D-Trp22,125I-Tyr25]somatostatin-28 preferentially labelled the strata oriens and radiatum of the CA1 subfield of the hippocampus, the molecular layer of the dentate gyrus, the subiculum and presubiculum of the hippocampal formation, the inner layer of the frontal cortex, and the lateral and basolateral nuclei of the amygdala. The non-subtype-selective radioligand [125I]CGP 23996 (in 5 mM Mg2+ buffer) preferentially labelled the strata oriens and radiatum of the CA1 subfield of the hippocampus, the subiculum and the basolateral nucleus of the amygdala. Under conditions where primarily somatostatin-2 receptors were labelled, [125I]CGP 23996 (in 120 mM Na+ buffer) showed strong binding in the strata oriens and radiatum of the CA1 subfield of the hippocampus and the frontal cortex, whereas the dentate gyrus, subiculum and amygdala showed only weak signals. During and after kindling, no significant differences were observed between the ipsi- and contralateral sides of the hippocampus. A significant decrease (about 40%) of somatostatin receptor binding sites was observed in the molecular layer of the dentate gyrus with all radioligands (except [125I]CGP 23996 in Na+ buffer, which did not label this area) at stage 2 (pre-convulsive stage) and one week, but not one month, after stage 5 (generalized motor seizures). In contrast to somatostatin receptor binding, no alterations of the messenger RNA levels for sst1-sst5 receptors were found either at stage 2 or at stage 5. Similarly, no changes in receptor binding or messenger RNA levels were observed in the brain of rats which experienced a single afterdischarge. The present study shows a significant and selective decrease of somatostatin-1 receptor binding sites in the dentate gyrus of kindled rats. This is part of the plastic changes induced by kindling and may contribute to the increased sensitivity for the induction of generalized seizures during kindling. 相似文献
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Sarah JS Domingues Francislete R Melo Juliana M Aguiar Adriana G Affonso Juclia SA Giuli Juliana L Rose Maurício P Sales Lara F Machado Cassiana R Azevedo Patrícia C da Cunha Adriana Ferreira Uchoa Antnia Elenir Amncio de Oliveira Jos Xavier‐Filho Ktia VS Fernandes 《Journal of the science of food and agriculture》2006,86(12):1977-1985
We have investigated the survival of Callosobruchus maculatus larvae when reared on resistant IT81D 1045 Vigna unguiculata seeds, whose resistance has been associated with variant forms of vicilins. Here, we present data which show that larvae of C. maculatus feeding on embryonic axis of resistant cowpea reach a mass of around 28 times higher than those feeding on cotyledonary tissues. Additionally, incorporation of 5–10% of embryonic axis flour on artificial seeds made of resistant flour restores toxicity of seeds to the bruchid. Vicilins purified from both susceptible and resistant embryonic axis had no deleterious effects either on insect development or on insect survival until a level of 4% of incorporation. In contrast, vicilins from resistant cotyledons show an LD50 (50% lethal dose) and WD50 (half weight dose) of 2%. Total vicilin contents of embryonic axes were around two times lower than in cotyledonary tissues, while proteolytic activities of all four proteinase classes were always higher in the former tissues. By 2D‐PAGE we visualized eight protein spots, which seem to be exclusively found on resistant cotyledons. Copyright © 2006 Society of Chemical Industry 相似文献
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Arun Kumar Kareem A. Mosa Liyao Ji Udaykumar Kage Dhananjay Dhokane Shailesh Karre 《Critical reviews in food science and nutrition》2018,58(11):1791-1807
Today, the dramatic changes in types of food consumed have led to an increased burden of chronic diseases. Therefore, the emphasis of food research is not only to ensure quality food that can supply adequate nutrients to prevent nutrition related diseases, but also to ensure overall physical and mental-health. This has led to the concept of functional foods and nutraceuticals (FFNs), which can be ideally produced and delivered through plants. Metabolomics can help in getting the most relevant functional information, and thus has been considered the greatest –OMICS technology to date. However, metabolomics has not been exploited to the best potential in plant sciences. The technology can be leveraged to identify the health promoting compounds and metabolites that can be used for the development of FFNs. This article reviews (i) plant-based FFNs-related metabolites and their health benefits; (ii) use of different analytic platforms for targeted and non-targeted metabolite profiling along with experimental considerations; (iii) exploitation of metabolomics to develop FFNs in plants using various biotechnological tools; and (iv) potential use of metabolomics in plant breeding. We have also provided some insights into integration of metabolomics with latest genome editing tools for metabolic pathway regulation in plants. 相似文献
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VV Iasnetsov VS Shashkov SB Kozlov VA Pravdivtsev AV Shashkov MG Potapov 《Canadian Metallurgical Quarterly》1997,(12):26-34
The authors' own findings and the data available in the literature as to movement diseases (MD) in animals and man were reviewed in the context of P. K. Anokhin's theory of functional systems. The functional system of the human body's gravity center is detailed. There is evidence for that disintegration processes underlying MD first occur in the mnestic sphere since due to genetic and/or ontogenetic causes, memory has no preserved no motor programme required to achieve the end net efficiency of performance of this functional system,--to maintain the definite position of the gravity center of the body and its related vegetative status upon stress-induced vestibular exposures. Based on the above concepts of the pathogenesis of MD, its preventive measures have been proposed and tested, which include drug (nootropic agents) and non-drug (a special complex of physical exercises for children aged 2 to 7 years, which will form permanent motor programs in memory in definite periods of their ontogenesis) measures. 相似文献
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JH Callicott MF Egan A Bertolino VS Mattay FJ Langheim JA Frank DR Weinberger 《Canadian Metallurgical Quarterly》1998,44(10):941-950
BACKGROUND: Shared neurobiological characteristics of patients with schizophrenia and their siblings may represent "intermediate phenotypes" that may more closely reflect the genetic susceptibility underlying this illness. We sought evidence of such phenotypes using magnetic resonance spectroscopy based on previously described regional abnormalities in levels of the neuronal marker N-acetyl-aspartate (NAA) in the hippocampal area and dorsolateral prefrontal cortex of patients with schizophrenia. METHODS: We studied 47 schizophrenics, 60 unaffected siblings, and 66 healthy control subjects with long echo time multislice proton magnetic resonance spectroscopic imaging, primarily measuring NAA, creatine plus phosphocreatine (CRE), and choline-containing compounds. RESULTS: Both patients and their unaffected siblings had significant reductions in hippocampal area NAA/CRE as compared with control subjects. As exploratory analyses, estimates of heritability were performed. Although quantitative correlation of hippocampal NAA between patients and sibs was low (likely reflecting measurement noise), qualitatively defined "low hippocampal NAA/CRE phenotypes" yielded relative risk estimates (lambda s) of between 3.8 and 8.8, suggesting this characteristic is heritable. CONCLUSIONS: Our finding adds to the evidence that hippocampal abnormalities are associated with schizophrenia and may represent a novel biological phenotype for genetic studies of schizophrenia. 相似文献
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