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41.
As genetic and environmental influences on schizophrenia might converge on DNA methylation (DNAm) within loci which are both associated with the disease and implicated in response to environmental stress, we examined whether DNAm within CYP17A1, a hypothalamus–pituitary–adrenal axis gene which is situated within the schizophrenia risk locus 10q24.32, would mediate genetic and environmental effects on stress-related schizophrenia symptoms. DNAm within an exonic–intronic fragment of CYP17A1 was assessed in the blood of 66 schizophrenia patients and 63 controls using single-molecule real-time bisulfite sequencing. Additionally, the VNTR polymorphism of the AS3MT gene, a plausible causal variant within the 10q24.32 locus, was genotyped in extended patient and control samples (n = 700). The effects of local haplotype, VNTR and a polyenviromic risk score (PERS) on DNAm, episodic verbal memory, executive functions, depression, and suicidality of patients were assessed. Haplotype and PERS differentially influenced DNAm at four variably methylated sites identified within the fragment, with stochastic, additive, and allele-specific effects being found. An allele-specific DNAm at CpG-SNP rs3781286 mediated the relationship between the local haplotype and verbal fluency. Our findings do not confirm that the interrogated DNA fragment is a place where genetic and environmental risk factors converge to influence schizophrenia symptoms through DNAm.  相似文献   
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Glioblastoma (GBM) is the most common and deadly primary brain tumor in adults. Understanding GBM pathobiology and discovering novel therapeutic targets are critical to finding efficient treatments. Upregulation of the lysosomal cysteine carboxypeptidase cathepsin X has been linked to immune dysfunction and neurodegenerative diseases, but its role in cancer and particularly in GBM progression in patients is unknown. In this study, cathepsin X expression and activity were found to be upregulated in human GBM tissues compared to low-grade gliomas and nontumor brain tissues. Cathepsin X was localized in GBM cells as well as in tumor-associated macrophages and microglia. Subsequently, potent irreversible (AMS36) and reversible (Z7) selective cathepsin X inhibitors were tested in vitro. Selective cathepsin X inhibitors decreased the viability of patient-derived GBM cells as well as macrophages and microglia that were cultured in conditioned media of GBM cells. We next examined the expression pattern of neuron-specific enzyme γ-enolase, which is the target of cathepsin X. We found that there was a correlation between high proteolytic activity of cathepsin X and C-terminal cleavage of γ-enolase and that cathepsin X and γ-enolase were colocalized in GBM tissues, preferentially in GBM-associated macrophages and microglia. Taken together, our results on patient-derived material suggest that cathepsin X is involved in GBM progression and is a potential target for therapeutic approaches against GBM.  相似文献   
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Energetic carbon ions are promising projectiles used for cancer radiotherapy. A thorough knowledge of how the energy of these ions is deposited in biological media (mainly composed of liquid water) is required. This can be attained by means of detailed computer simulations, both macroscopically (relevant for appropriately delivering the dose) and at the nanoscale (important for determining the inflicted radiobiological damage). The energy lost per unit path length (i.e., the so-called stopping power) of carbon ions is here theoretically calculated within the dielectric formalism from the excitation spectrum of liquid water obtained from two complementary approaches (one relying on an optical-data model and the other exclusively on ab initio calculations). In addition, the energy carried at the nanometre scale by the generated secondary electrons around the ion’s path is simulated by means of a detailed Monte Carlo code. For this purpose, we use the ion and electron cross sections calculated by means of state-of-the art approaches suited to take into account the condensed-phase nature of the liquid water target. As a result of these simulations, the radial dose around the ion’s path is obtained, as well as the distributions of clustered events in nanometric volumes similar to the dimensions of DNA convolutions, contributing to the biological damage for carbon ions in a wide energy range, covering from the plateau to the maximum of the Bragg peak.  相似文献   
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The development of cost‐effective and flexible electrodes is demanding in the field of energy storage. Herein, flexible FexOy/nitrogen‐doped carbon films (FexOy/NC‐MOG) are prepared by facile electrospinning of Fe‐based metal–organic gels (MOGs) followed by high‐temperature carbonization. This approach allows the even mixing of fragile coordination polymers with polyacrylonitrile into flexible films while reserving the structural characteristics of coordination polymers. After thermal treatment, FexOy/NC‐MOG films possess uniformly distributed FexOy nanoparticles and larger accessible surface areas than traditional FexOy‐NC films without MOG. Taking advantage of the unique structure, FexOy/NC‐MOG exhibits a superior rate performance (449.8 mA h g?1 at 5000 mA g–1) and long cycle life (629.3 mA h g–1 after 500 cycles at 1000 mA g–1) when used as additive‐free anodes in lithium‐ion batteries.  相似文献   
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Black melanin inks are prepared to selectively exhibit colors under strong light, inspired by human hair. High absorbance of melanin suppresses multiple scattering, causing resonant Mie scattering predominant. Various colors can be developed as the resonant wavelength dictated by nanosphere diameter. Therefore, the melanin inks can be used to encrypt and selectively disclose multicolor patterns for anticounterfeiting applications.  相似文献   
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