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Islet transplantation has become a promising treatment in the therapy of type 1 diabetes. Its function improvement, after isolation and before transplantation, is crucial because of their loss both in number and function of islets after isolation procedures. Trace elements sodium orthovanadate (SOV) and sodium molybdate (SM), as well as medicinal plant Teucrium polium L. (TP), showed and possessed high beneficial antioxidative potential and even hypoglycemic properties via their effect on islets. We evaluated the effect of these components in combination on cultured islet function in order to improve pancreatic islet transplantation. Rat pancreatic islets were cultured for 24 h then incubated with different concentrations of TP (0.01 and 0.1 mg/mL) alone and in combination with SOV (1 mM) or SM (1 mM). Insulin concentration in buffer media was measured as islet secretory function. Administration of TP (0.01 mg/mL), SM, and SOV alone or in combination with each other significantly increased insulin secretion at high glucose concentration (16.7 mM); insulin secretion was significantly greater in the group containing both TP and SM than other treated groups (p < 0.05). The combination of the mentioned trace elements especially molybdate with TP could improve islet cells function before transplantation.  相似文献   
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In this study, we extracted the essential oils of the stem, leaf, and flower of Achillea filipendulina, analyzed them, and studied their antibacterial properties. Of 16, 53, and 35 compounds identified in the stem, leaf, and flowers, respectively, only five are present in all three segments of the plant. The essential oil of the stem was mainly composed of neryl acetate, spathulenol, carvacrol, santolina alcohol, and trans‐caryophyllene oxide. However, the main identified components of leaf were 1,8‐cineole, camphor, ascaridole, trans‐isoascaridole, and piperitone oxide and the main components of the flower oil were ascaridole, trans‐isoascaridole, 1,8‐cineole, p‐cymene, and camphor. The extracted oil from different segments demonstrated varying antibacterial properties against both Gram‐positive and Gram‐negative bacteria, demonstrated by disk, minimum inhibitory concentration, and minimum bactericidal concentration methods. These suggest that the application of all segments of aerial parts of A. filipendulina may have a better therapeutic effect in fighting pathogenic systems.  相似文献   
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Varicose veins are the most common vascular disease in humans. Veins have valves that help the blood return gradually to the heart without leaking blood. When these valves become weak, blood and fluid collect and pool by pressing against the walls of the veins, causing varicose veins. In the cardiovascular system, mechanical forces are important determinants of vascular homeostasis and pathological processes. Blood vessels are constantly exposed to a variety of hemodynamic forces, including shear stress and environmental strains caused by the blood flow. In varicose veins within the leg, venous blood pressure rises in the vein of the lower extremities due to prolonged standing, creating a peripheral tension in the vessel wall thereby causing mechanical stimulation of endothelial cells and vascular smooth muscle. Studies have shown that long-term increased exposure to vascular wall tension is associated with the overexpression of HIF-1α and HIF-2α and increased levels of MMP-2 and MMP-9, thereby reducing venous contraction and progressive venous dilatation, which is involved in the development of varicose veins. Following the expression of metalloproteinase, the expression of type 1 collagen increases, and the amount of type 3 collagen decreases. Therefore, collagen imbalance will cause the varicose veins to not stretch. Loss of structural proteins (type 3 collagen and elastin) in the vessel wall causes the loss of the biophysical properties of the varicose vein wall. This review article tries to elaborate on the effect of mechanical forces and sensors of these forces on the vascular wall in creating the mechanism of mechanosignaling, as well as the role of the onset of molecular signaling cascades in the pathology of varicose veins.  相似文献   
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A thermo-alkaliphilic lipase from Bacillus subtilis DR8806 was functionally expressed as an N-terminal 6xHis-tagged recombinant enzyme in Escherichia coli BL21 using pET-28a(+) expression vector. Sequence analysis revealed an open reading frame of 639 bp encoding a 212-amino acid protein containing the well-conserved Ala-His-Ser-Met-Gly motif. One-step purification of the His-tagged recombinant lipase was achieved using Ni-NTA affinity chromatography with a specific activity of 1364 U/mg. The purified enzyme with an apparent molecular mass of 26.8 kDa demonstrated the maximum activity at 70 °C and pH 8.0 for hydrolysis of p-nitrophenylbutyrate as substrate. The enzyme activity was strongly inhibited by divalent ions of heavy metals such as Hg2+ and Cu2+, while retained over 90% of the original activity in the presence of several reagents including DTNB (5,5′-dithiobis-(2-nitrobenzoic acid)), SDS (sodium dodecyl sulfate), urea, DMF (dimethylformamide), DTT (dithiothreitol), glycerol and Triton X-100. While being considerably stable in organic solvents, imidazolium-based ionic liquids (ILs) had stimulatory effects on the activity of purified lipase. Remarkable stabilization of enzyme at alkaline pH and in ionic liquids as well as its thermostability/thermoactivity are among the most fundamental characteristics which offer great potential for various biotechnological applications including detergent formulation, bioremediation processes and biotransformation in non-aqueous media.  相似文献   
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Candida albicans (C. albicans) cell wall beta-glucan has been considered as a potential agent in the treatment of cancers due to its anti-tumor properties. Therefore, in the present study, we investigated the anti-cancer effects of Candida cell wall beta-glucan on Lewis lung carcinoma cell line (LL/2) cells. Beta-glucan of C. albicans cell wall was extracted. LL/2 cell line was cultured, then sphere cells and parental cells were exposed to the different concentrations of beta-glucan extracted from C. albicans (10–6000 μg/ml), for 24, 48 and 72 h. Cytotoxicity of beta-glucan was assayed by MTT test, then RNA extracted from cells population (treated and untreated cells), cDNA synthetized and expression level of Sox2, Oct4, C-myc, Nanog genes were also investigated using Real-time methods. At optimal concentrations of 800 and 1000 μg/ml, the extracted beta-glucan showed a significant cytotoxic effect on both parental and sphere cell populations (p?<?0.05). Real-time PCR analysis revealed a decreased expression of Oct4 and Sox2 genes in treatment of cells with beta-glucan compared with control group. Since the extracted beta-glucan showed an inhibitory effect on the expression of Oct4 and Sox2 genes involved in LL/2 metastasis, therefore, beta-glucan can be considered as an anti-tumor agent because of its anti-metastatic properties, however, more in vitro and in vivo studies are needed to provide further evidence on this topic in the future.

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This article examines the challenges associated with the experience of upward educational mobility among descendants of North African immigrants in France. Drawing on in-depth, open-ended interviews with students and graduates of the prestigious grandes écoles, it sheds light on three specific ways in which class-based and ethno-racial inequalities intersect to shape the mobility costs that our respondents outline: (1) feelings of isolation resulting from being one of the only bursar recipients and ethno-racial minorities of their schools; (2) perceived conflation of their minority background with counter-elite dispositions; and (3) difficulties of adjusting to a student life reflecting the cultural styles of the predominantly white, upper-middle-class group. The article suggests that our respondents deploy a minority culture of mobility rooted in class and ethno-racial processes to overcome these challenges. It finally discusses implications for future research, stressing the need to examine the intersecting effect of multiple social categories in informing complex mobility experiences.  相似文献   
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