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Besides its well-established oncosuppressor activity, a key function of p53 in regulating metabolic pathways has been recently identified. Nevertheless, the role of p53 with respect to diabetes mellitus (DM) appears highly controversial. To address this issue, we have used the cis-imidazoline compound Nutlin-3, an inhibitor of MDM2/p53 interaction, which represents a potent and selective non-genotoxic activator of the p53 pathway both in in vivo and in vitro experimental settings. Experimental DM was induced by intraperitoneal injections of low concentrations of streptozotocin (STZ) in C57BL/6N mice (n = 20). A group of control vehicle-injected mice (n = 10) and of STZ-treated mice (n = 10) was co-injected with Nutlin-3. Mice co-injected with STZ + Nutlin-3 exhibited attenuated features of DM with respect to animals treated with STZ alone. Indeed, STZ + Nutlin-3-treated mice were characterized by significantly (p < 0.05) lower levels of hyperglycemia, reduced weight loss, and increased spleen weight. In addition, STZ alone promoted a marked decrease in the levels of several circulating cytokines, including interleukin-12 (IL-12)p40. On the other hand, co-injection of STZ + Nutlin-3 significantly (p < 0.01) counteracted IL-12p40 down-modulation. In vitro experiments performed on the RAW264.7 macrophagic cell line model, used as cellular source of IL-12p40, demonstrated that Nutlin-3 treatment increased IL-12p40 release, strongly suggesting a direct effect of Nutlin-3 on the immune system. Overall, these data demonstrate that systemic administration of Nutlin-3 ameliorates the severity of STZ-induced DM and increases the levels of circulating IL-12p40.  相似文献   
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Background: There is a rising debate concerning the possible side effects arising from the use of particles at nanosize since the production of nanomaterials is increasing worldwide. Nanoparticles are able to enter the body through the skin, lungs or intestinal tract, depositing in several organs, and the risk associated with exposure to them, the routes of entry and the molecular mechanisms of any cytotoxicity need to be well understood. The aim of this work was to evaluate the suitability of skin replica as a method to study the colloidal systems visualization and distribution on skin surface. Methods: Solid lipid nanoparticles (SLN) were used as carrier systems. Skin replicas on healthy volunteers, before and after SLN application, were prepared and visualized using profilometry and scanning electron microscopy (SEM). Results: The results obtained in our study show that skin replica represents a suitable method to study the colloidal systems and their interaction with the skin surface. Conclusion: Profilometry enabled us to observe the systems distribution on a cutaneous texture. In addition, SEM, thanks to its high magnifications and field depth, allowed us to evaluate particles' distribution on the skin texture and the interaction between particles of different compositions and replica silicone.  相似文献   
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Objectives: Conjugated linoleic acid (CLA) isomers have been shown to possess anti-inflammatory activity in the central nervous system. In this study, we aimed to evaluate whether modulation of the fatty acid profile by the CLA isomers c9,t11 or t10,c12CLA was associated with changes in the expression of pro-inflammatory molecules in human astrocytes.

Methods: Cultured astrocytes were treated for 6 days with 100?µM fatty acids (c9,t11CLA or t10,c12CLA or oleic acid). Following the treatment, the fatty acid profile of the cell and pro-inflammatory molecule expression were assessed.

Results: Only the t10,c12CLA isomer induced a significant decrease in arachidonic acid and increased the ratio of docosahexaenoic acid/eicosapentaenoic acid, which constitutes indirect evidence of peroxisome proliferator-activated receptor alpha activation. Inhibition of tumour necrosis factor-α, interleukin-1β, and RANTES expression was observed in astrocytes treated with c9,t11CLA and t10,c12CLA.

Discussion: Current data demonstrate that CLA isomers, particularly t10,c12, may affect neuroinflammation by reducing the pro-inflammatory molecules in cultured astrocytes, suggesting a potential nutritional role of CLA isomers in modulating the astrocyte inflammatory response.  相似文献   

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Therapy with Vitamin K antagonists (VKA) effectively reduces the thrombosis risk in many clinical conditions. Genetic variants of vitamin K epoxide reductase (VKORC-1) are associated with increased VKA effect and bleeding risk. It is unknown whether these variants could also affect the long-term outcome in patients with high-dosage oral anticoagulation and/or more difficult adherence to the therapeutic INR range. Hundred and twenty-four patients with mechanical heart valve replacement assuming VKA were genotyped for VKORC-1 ?1639G>A (Rs9923231) polymorphism. Hemorrhage, venous thrombosis and atherothrombotic events were retrospectively assessed for a 6-year period. Furthermore, stability of their INR in relationship with the VKORC-1 genotype was investigated day-by-day for 3?months. No differences were observed in hemorrhage and venous thrombosis events according to rs 9923231. GG genotype carriers (n?=?41) had no atherothrombotic events, while 4 strokes, 4 TIA and 3 AMI were diagnosed in A carriers (n?=?83; P?=?0.0008). During the daily observation period, A allele carriers had lower VKA requirements (4.7, 3.7, 2.2?mg/day for GG/GA/AA genotype respectively; P?=?0.00001), higher mean INR (2.7, 2.8, 2.9; P?=?0.05) and a higher number of examinations above the therapeutic range than GG carriers (17 % vs. 0 % in GG genotype, P?=?0.036). Conversely, patients with GG genotype had a more stable dosage of VKA (P?=?0.006) and a higher percentage of examinations under the therapeutic range (51, 43 and 36 % in GG, GA and AA genotype, respectively, P?=?0.040). In patients with high dosage VKA, VKORC-1 polymorphism is associated to a different warfarin dosage, anticoagulation level, time spent outside the therapeutic range and, in the long-term, a different incidence of atherothrombotic events.  相似文献   
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Blood donor specimens from South-west Scotland were analysed for the following polymorphisms: ABO, Rhesus (D), Haptoglobin, Transferrin, Immunoglobulin (GM), RBC acid phophatase, RBC phosphoglucomutase and RBC adenylate kinase.

Genetic differences exist between the regions in S.W. Scotland and between S.W. Scotland and other Irish and Irish Sea regions. This variability is detailed and discussed. The results are mapped by converting the data into distance values and by using a non-metrical scaling technique. Overall the present S.W. Scotland data are similar to Cumbrian and Manx results and dissimilar to the Irish data.  相似文献   
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