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Background  

Parthenocarpy, or fruit development in the absence of fertilization, has been genetically engineered in eggplant and in other horticultural species by using the DefH9-iaaM gene. The iaaM gene codes for tryptophan monoxygenase and confers auxin synthesis, while the DefH9 controlling regions drive expression of the gene specifically in the ovules and placenta. A previous greenhouse trial for winter production of genetically engineered (GM) parthenocarpic eggplants demonstrated a significant increase (an average of 33% increase) in fruit production concomitant with a reduction in cultivation costs.  相似文献   
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Biopolymers are increasingly employed for neuroscience applications as scaffolds to drive and promote neural regrowth, thanks to their ability to mediate the upload and subsequent release of active molecules and drugs. Synthetic degradable polymers are characterized by different responses ranging from tunable distension or shrinkage to total dissolution, depending on the function they are designed for. In this paper we present a biocompatible microfabricated poly-ε-caprolactone (PCL) scaffold for primary neuron growth and maturation that has been optimized for the in vitro controlled release of brain-derived neurotrophic factor (BDNF). We demonstrate that the designed morphology confers to these devices an enhanced drug delivery capability with respect to monolithic unstructured supports. After incubation with BDNF, micropillared PCL devices progressively release the neurotrophin over 21 days in vitro. Moreover, the bioactivity of released BDNF is confirmed using primary neuronal cultures, where it mediates a consistent activation of BDNF signaling cascades, increased synaptic density, and neuronal survival. These results provide the proof-of-principle on the fabrication process of micropatterned PCL devices, which represent a promising therapeutic option to enhance neuronal regeneration after lesion and for neural tissue engineering and prosthetics.  相似文献   
34.
The neuronal RNA‐binding protein HuD is involved in synaptic plasticity and learning and memory mechanisms. These effects are thought to be due to HuD‐mediated stabilization and translation of target mRNAs associated with plasticity. To investigate the potential role of HuD in drug addiction, we first used bioinformatics prediction algorithms together with microarray analyses to search for specific genes and functional networks upregulated within the forebrain of HuD overexpressing mice (HuDOE). When this set was further limited to genes in the knowledgebase of addiction‐related genes database (KARG) that contains predicted HuD‐binding sites in their 3′ untranslated regions (3′UTRs), we found that HuD regulates networks that have been associated with addiction‐like behavior. These genes included Bdnf and Camk2a, 2 previously validated HuD targets. Since addiction is hypothesized to be a disorder stemming from altered gene expression causing aberrant plasticity, we sought to test the role of HuD in cocaine conditioned placed preference (CPP), a model of addiction‐related behaviors. HuD mRNA and protein were upregulated by CPP within the nucleus accumbens of wild‐type C57BL/6J mice. These changes were associated with increased expression of Bdnf and Camk2a mRNA and protein. To test this further, we trained HuDOE and wild‐type mice in CPP and found that HuDOE mice showed increased cocaine CPP compared with controls. This was also associated with elevated expression of HuD target mRNAs and proteins, CaMKIIα and BDNF. These findings suggest HuD involvement in addiction‐related behaviors such as cocaine conditioning and seeking, through increased plasticity‐related gene expression.  相似文献   
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The aim of this study was to test whether patients with symptomatic food allergy and significant levels of immunoglobulin E (IgE) to alimentary antigens were more likely infected by H. pylori, especially by strains expressing the CagA protein, with respect to controls. A group of 38 patients with symptomatic food allergy and 53 age-matched controls were examined serologically for H. pylori infectious status, and for CagA seropositivity. IgE to alimentary allergens were measured by a commercial kit. The prevalence of H. pylori infection in patients with food allergy and controls was similar (42.1%, and 48.3%, respectively). However, anti-CagA antibodies in H. pylori-infected persons were detected in 62.5% of patients with food allergy, and 28% of controls (P = 0.030, odds ratio = 4.29). The mean level of IgE to the most common alimentary antigens in serum samples from infected patients with anti-CagA antibodies was significantly higher than in CagA-negative infected patients: 3.28 kU/L (SD 3.93), vs. 1.99 kU/L (SD 1.53), P = 0.002, 95% confidence interval = 0.61 to 2.53). Infection by CagA-positive H. pylori increases the risk of developing food allergy.  相似文献   
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The inherent toxicity of many metal compounds, together with their widespread environmental distribution, raises concerns of potential health hazards. Little is known about the impact of these important environmental toxicants on adult stem/progenitor cells, necessary for tissue homeostasis and repair. We recently reported that autophagy is implicated in the response of hematopoietic stem/progenitor cells to toxic concentrations of hexavalent chromium (Cr[VI]) and cadmium (Cd), two well known carcinogenic heavy metal cations. Autophagy may lead to cell death if carried out too extensively, but also acts as a survival pathway in cells under stress. In stem/progenitor cells, an autophagic phenotype could mitigate metal-induced toxicity, contributing to the conservation of tissue renewal capability. Given the key role of toxic damage to adult stem/progenitor cells in cancer, it is necessary to investigate whether autophagic responses modulate the carcinogenic potential of exposure to heavy metals during stem/progenitor cell differentiation.  相似文献   
39.
A novel series of non-hydroxamate HDAC inhibitors (HDACi) showing a uracil group at the left and a 2-aminoanilide/2-aminoanilide-like portion at the right head have been reported. In particular, the new compounds incorporating a 2-aminoanilide moiety behaved as class I-selective HDACi. Compound 8, the most potent and class I-selective, showed weak apoptosis (higher than MS-275) joined to cytodifferentiating activity on U937 cells. Surprisingly, the highest differentiation was observed with 13, through an effect that seems to be unrelated to HDAC inhibition.  相似文献   
40.
A potent sigma-2 receptor ligand, known as PB28, was tritium radiolabelled and biologically evaluated. The results showed that [(3)H]PB28 and the corresponding unlabelled PB28 had superimposed pharmacodynamic properties. This radioligand appears as a potential candidate for receptor binding and in living cells assays.  相似文献   
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