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11.
Psychopathic offenders show a persistent pattern of emotional unresponsivity to the often horrendous crimes they perpetrate. Recent studies have related psychopathy to alterations in white matter. Therefore, diffusion tensor imaging followed by tract-based spatial statistics (TBSS) analysis in 11 psychopathic offenders matched to 11 healthy controls was completed. Fractional anisotropy was calculated within each voxel and comparisons were made between groups using a permutation test. Any clusters of white matter voxels different between groups were submitted to probabilistic tractography. Significant differences in fractional anisotropy were found between psychopathic offenders and healthy controls in three main white matter clusters. These three clusters represented two major networks: an amygdalo-prefrontal network, and a striato-thalamo-frontal network. The interpersonal/affective component of the PCL-R correlated with white matter deficits in the orbitofrontal cortex and frontal pole whereas the antisocial component correlated with deficits in the striato-thalamo-frontal network. In addition to replicating earlier work concerning disruption of an amygdala-prefrontal network, we show for the first time that white matter integrity in a striato-thalamo-frontal network is disrupted in psychopathic offenders. The novelty of our findings lies in the two dissociable white matter networks that map directly onto the two major factors of psychopathy.  相似文献   
12.

Glioblastoma multiform (GBM) is known as an aggressive glial neoplasm. Recently incorporation of mesenchymal stem cells with anti-tumor drugs have been used due to lack of immunological responses and their easy accessibility. In this study, we have investigated the anti-proliferative and apoptotic activity of atorvastatin (Ator) in combination of mesenchymal stem cells (MSCs) on GBM cells in vitro and in vivo. The MSCs isolated from rats and characterized for their multi-potency features. The anti-proliferative and migration inhibition of Ator and MSCs were evaluated by MTT and scratch migration assays. The annexin/PI percentage and cell cycle arrest of treated C6 cells were evaluated until 72 h incubation. The animal model was established via injection of C6 cells in the brain of rats and subsequent injection of Ator each 3 days and single injection of MSCs until 12 days. The growth rate, migrational phenotype and cell cycle progression of C6 cells decreased and inhibited by the interplay of different factors in the presence of Ator and MSCs. The effect of Ator and MSCs on animal models displayed a significant reduction in tumor size and weight. Furthermore, histopathology evaluation proved low hypercellularity and mitosis index as well as mild invasive tumor cells for perivascular cuffing without pseudopalisading necrosis and small delicate vessels in Ator?+?MSCs condition. In summary, Ator and MSCs delivery to GBM model provides an effective strategy for targeted therapy of brain tumor.

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13.
Abstract

Entomopathogenic fungi are among the most successful biocontrol agents for preventing economic loss from insects. The identification of virulent species or isolates, the development of formulation technology and the improvement of efficiency are avenues being pursuing by researchers in diverse scientific disciplines. A successful entomopathogenic fungus deploys a combination of mechanical and biochemical processes to overcome the first defensive barrier in insects, the integument. A precise understanding of the mechanisms underlying fungal pathogenicity, particularly the roles of enzymes such as proteases, is essential in order to highlight the potential of entomopathogenic fungi and increase their virulence via genetic modifications. Cuticle-degrading proteases are divided into subtilisin-like (Pr1) and trypsin-like (Pr2) proteases, which are secreted in the initial stages of penetration. The biochemical structure contains the catalytic triad Asp39, His69 and Ser224 in addition to Ca2+ binding sites. Studies have shown a molecular weight of almost 19–47?kDa, an optimal pH of 7–12 and an optimal temperature of 35–45?°C. Different species or isolates of entomopathogenic fungi exhibit differences in the secretion and activity of cuticle-degrading proteases, which may indicate their virulence capacity. Genetic engineering techniques have been developed to create isolates with protease overexpression. Such isolates have significantly higher virulence against the host because they not only ensure fungal penetration but also exhibit direct toxicity to insects.  相似文献   
14.
Digestion in insects is a multi-step process to afford nutritional requirements of biological activities. The process starts with nervous stimuli and continues with biochemical activities of digestive enzymes as well as several pumps to digest and absorb the obtained molecules. Carbohydrases, lipases and proteases are the three main digestive enzymes involved in digestion process. Lipases seem to be very important not only for digestive role but also for esteratic activity so that some experts consider lipases as the Class 3 of general esterases. Digestive lipases divided into different groups based on their biological roles namely triacylglycerol lipases, phospholipases and two types of phosphatases. Briefly, triacylglycerol lipases (TAG-lipases) are the hydrolysing enzymes that affect the outer esteric links of triacylglycerols in ingested food. Phospholipases including PLA2 and PLA1 remove phosphatide fatty acids attached to the Position 2 and Position 1. Finally, Alkaline and acid phosphatases are the enzymes that hydrolyse phosphomonoesters under alkaline or acid conditions, respectively. In this review, presence and physiological role of digestive TAG-lipases are explained and their possible importance will be discussed in insect.  相似文献   
15.
16.
Congenital nevi develop before birth and sometimes cover large areas of the body. They are presumed to arise from the acquisition of a gene mutation in an embryonic melanocyte that becomes trapped in the dermis during development. Mice bearing the Cdk4R24C::Tyr‐NRASQ61K transgenes develop congenital nevus‐like lesions by post‐natal day 10, from melanocytes escaping the confines of hair follicles. We interbred these mice with the collaborative cross (CC), a resource that enables identification of modifier genes for complex diseases (those where multiple genes are involved). We examined variation in nevus cell density in 66 CC strains and mapped a large‐effect quantitative trait locus (QTL) controlling nevus cell density to murine chromosome 9. The best candidate for a gene that exacerbates congenital nevus development in the context of an NRAS mutation is Cdon, a positive regulator of sonic hedgehog (Shh) that is expressed mainly in keratinocytes.  相似文献   
17.
The invasive freshwater mollusc Dreissena bugensis (quagga mussel) sticks to underwater surfaces via a proteinacious ‘anchor’ (byssus), consisting of a series of threads linked to adhesive plaques. This adhesion results in the biofouling of crucial underwater industry infrastructure, yet little is known about the proteins responsible for the adhesion. Here the identification of byssal proteins extracted from freshly secreted byssal material is described. Several new byssal proteins were observed by gel electrophoresis. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used to characterize proteins in different regions of the byssus, particularly those localized to the adhesive interface. Byssal plaques and threads contain in common a range of low molecular weight proteins, while several proteins with higher mass were observed only in the plaque. At the adhesive interface, a plaque-specific ~8.1 kDa protein had a relative increase in signal intensity compared to the bulk of the plaque, suggesting it may play a direct role in adhesion.  相似文献   
18.
International Journal of Peptide Research and Therapeutics - Varicocele, abnormal dilatation of the spermatic vein, is one of the most common andrological disease found during a male physical...  相似文献   
19.
The hypoxic niche of tumor leads to a tremendous increase in the extracellular adenosine concentration through alteration of adenosine metabolism in the tumor microenvironment (TME). This consequently affects cancer progression, local immune responses, and apoptosis of tumor cells. Regulatory effect of adenosine on apoptosis in TME depends on the cancer cell type, pharmacological characteristics of adenosine receptor subtypes, and the adenosine concentration in the tumor niche. Exploiting specific pharmacological adenosine receptor agonist and antagonist inducing apoptosis in cancer cells can be considered as a proper procedure to control cancer progression. This review summarizes the regulatory role of adenosine in cancer cell apoptosis for a better understanding, and hence better management of the disease.  相似文献   
20.
The epithelial cell adhesion molecule (EpCAM) is a Type I transmembrane superficial glycoprotein antigen that is expressed on the surface of basolateral membrane of multiple epithelial cells with some exceptions such as epidermal keratinocytes, hepatocytes, thymic cortical epithelial cells, squamous stratified epithelial cells, and myoepithelial cells that do not express the molecule. The molecule plays a pivotal role in the structural integrity, adhesion of the epithelial tissues and their interaction with the underlying layers. EpCAM prevents claudin-7 and claudin-1 molecules from degradation, thereby, decreasing the number of tight junctions and cellular interconnections, and promoting the cells toward carcinogenic transformation. Moreover, the mutations in the EpCAM gene lead to congenital tufting enteropathy, severe intestinal epithelium homeostasis disorders, and Lynch and Lynch syndrome. Overexpression of EpCAM on stem cells of some cancers and the presence of this molecule on circulating tumor cells (CTCs) makes it a promising candidate for cancer diagnosis as well as tracing and isolation of CTCs.  相似文献   
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