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141.
Differentiation process of mesenchymal stem cells (MSCs) into adipocyte is involved in obesity. Multiple factors such as Ca2+ play important roles in different stages of this process. Because of the complicated roles of Ca2+ in adipogenesis, the aim of present investigation was to study the influx and efflux of Ca2+ into and out of the cells during adipogenesis. Adipose-derived MSCs were used to differentiate into adipocytes. MSCs were exposed to 2.5 mM Ca2+ or 1.8 mM Ca2+ plus calcium ionophore, A23187, for 3 days. Lipid staining, triglycerides (TG) content, and glyceraldehyde phosphate dehydrogenase (GAPDH) activity were evaluated to confirm the efficiency of the differentiation. Gene expression of GLUT4, PPARγ2, RAR-α, and calreticulin, as well as the protein levels of GLUT4 and PPARγ2 were determined. Ca2+ and in particular Ca2+ plus A23187 significantly lowered the efficiency of differentiation accompanied by decrease in intracellular TG deposits, GAPDH activity and alleviation of gene, and protein levels of GLUT4 and PPARγ2. While calreticulin and RAR-α were remarkably upregulated in A23187 group. This study showed the inhibitory effects of calcium in adipogenesis. Additionally, it indicated the greater inhibitory effect of calreticulin and RAR-α in controlling adipogenesis by higher levels of calcium.  相似文献   
142.
Targeted drug delivery is an attractive field in cancer studies. In this study, a novel fusion protein consisting of Shiga toxin A subunit and NGR peptide has been constructed. The cytotoxic Shiga toxin A subunit has the ability to kill cancer cells while NGR is a well-known peptide that targets the whole molecule to cancer cells. Two forms of this novel fusion protein, one without linker (A-NGR) and one with linker (A-GGGGS-NGR) were studied. 3D structure prediction of the two forms carried out by I-TASSER and their validation and analysis were performed by ProSA web and RAMPAGE. Results showed that A-NGR is a better model than the one with linker. A-NGR was constructed by PCR method and cloned in pBAD/gIII A vector. Then, it was successfully expressed in Escherichia coli by induction with arabinose and subsequently purified by affinity chromatography under denaturing condition. Ultimately, the cytotoxic effect of the purified protein was evaluated on U937 cancer cells and MRC-5 normal cells by MTT assay. Conclusively, the fusion protein was successfully cloned and expressed and evaluated for its cytotoxic effects. The IC50 value of A-NGR fusion protein for U937 cell was about 26.86 µg/ml while no cytotoxic effect was observed on MRC-5 cells. Therefore, considering the promising cytotoxic effects of the fusion protein, further in vitro evaluations of this fusion protein on different cell lines are underway.  相似文献   
143.
In order to compare the petroleum tolerance and phytoremediation ability of a native grass, Agropyron desertorum (desert Wheatgrass) with Cynodon spp. (Bermuda grass) in a petroleum hydrocarbon-contaminated soil, a 7-month greenhouse experiment was performed. There were 4 soil treatments with 0% (uncontaminated soil), 2%, 4%, and 12% (woil/wsoil) petroleum concentration. Parameters including shoot and root fresh weight and dry weight, root penetration depth and root density depth, soil respiration, and total petroleum hydrocarbons (TPH) degradation were measured during and after experiments. The results showed an increase in shoot fresh weight of A. desertorum in soil polluted with 2% petroleum sludge compared to the uncontaminated soil, whereas the growth of Bermuda grass significantly decreased in corresponding treatment. Root growth of A. desertorum was decreased in 2% and 4% petroleum sludge, whereas it was increased in Bermuda grass species. Overall, root fresh weight of Bermuda grass was higher than that of A. desertorum in all treatments. Significant increase in microorganisms' activity was observed in the presence of petroleum sludge and plants in soil compared with uncontaminated soil without plants, and the highest soil respiration (37.6 mg C-CO2/kg soil day) has been observed in the rhizosphere of Bermuda grass in treatment with 12% petroleum sludge. Plants had a significant role in the degradation of soil contaminants as TPH degradation in planted soils was significantly higher than that in unplanted soil (TPH degradation (%) was 30.4 and 38.9 in A. desertorum and Bermuda grass, respectively, whereas it was just 13.3 in unplanted soil). The rhizosphere of Bermuda grass had significantly less residual TPHs compared to A. desertorum. The results indicated that both Cynodon spp. and A. desertorum had a peculiar tolerance to petroleum pollution. Therefore, as Bermuda grass has already been suggested to be a typical and efficient species for phytoremediating petroleum-contaminated sites, A. desertorum may also prove to be a suitable native alternative.  相似文献   
144.
Molecular Biology Reports - Cystinuria is an autosomal recessive defect in reabsorptive transport of cystine and the dibasic amino acids ornithine, arginine, and lysine from renal tubule and small...  相似文献   
145.

Background

Neutralization of vascular endothelial growth factor receptor 1 (VEGFR1) and/or VEGFR2 is a widely used means of inhibiting tumor angiogenesis.

Methods

Based on the complex X-ray structures of VEGFA/VEGFR1, VEGFA/VEGFR2, and VEGFB/VEGFR1, a peptide (referred to as VGB) was designed to simultaneously bind to VEGFR1 and VEGFR2, and binding, antiangiogenic and antitumor properties of the peptide was investigated in vitro.

Results

VGB bound to both VEGFR1 and VEGFR2 in human umbilical vein endothelial cells (HUVECs) and 4?T1 mammary carcinoma tumor (MCT) cells, and inhibited the proliferation of HUVE, 4?T1 MCT, and U87 glioblastoma cells. Through abrogation of AKT and ERK1/2 phosphorylation, VEGFA-stimulated proliferation, migration, and two- and three-dimensional tube formation in HUVECs were inhibited more potently by VGB than by bevacizumab. In a murine 4?T1 MCT model, VGB strongly inhibited tumor growth without causing weight loss, accompanied by inhibition of AKT and ERK1/2 phosphorylation, a significant decrease in tumor cell proliferation (Ki-67 expression), angiogenesis (CD31 and CD34 expression), an increase in apoptosis index (increased TUNEL staining and p53 expression and decreased Bcl-2 expression), and the suppression of systematic spreading of the tumor (reduced NF-κB and MMP-9 and increased E-cadherin expression).

Conclusion

The dual specificity of VGB for VEGFR1 and VEGFR2, through which the PI3K/AKT and MAPK/ERK1/2 signaling pathways can be abrogated and, subsequently, angiogenesis, tumor growth, and metastasis are inhibited.

General significance

This study demonstrated that simultaneous blockade of VEGFR1 and VEGFR2 downstream cascades is an effective means for treatment of various angiogenic disorders, especially cancer.  相似文献   
146.
Breast cancer (BC) is the most commonly diagnosed cancer in women. The PI3K/AKT/mTOR pathway is among the most frequently dysregulated pathways in patients with BC. The activation of this pathway is associated with increased cell growth and clinical outcome, and its overexpression is associated with a poor prognosis. It has been proposed that it may be of importance as a potential therapeutic target in the treatment of BC. The aim of current review is to provide an overview of the potential utility of PI3K/Akt/mTOR inhibitors in patients with BC, with particular emphasis on recent preclinical and clinical studies. J. Cell. Biochem. 119: 213–222, 2018. © 2017 Wiley Periodicals, Inc.  相似文献   
147.
Autophagy is a cellular process for maintaining cellular homeostasis. This process can be induced by different factors, such as immune stimuli and pathogen-associated molecules. Autophagy has an important role in the control of IL-1β secretion by macrophages and other cell types. In present study, we describe a novel role for Iraqi propolis affecting autophagy in controlling the secretion of IL-1β in bone-marrow macrophages (BMDMs). After infection with Pseudomonas aeruginosa in the presence of propolis, the degradation of IL-1β was induced, and the activity of inflammasome was reduced. Iraqi propolis-induced autophagy in in vitro and in vivo models decreased the levels of IL-1β and caspase-1. Results indicated that IL-1β pathway production is regulated by autophagy via two different novel mechanisms, namely, regulation of the activation of NLRC4 inflammasome and IL-1β targeting for lysosomal degradation.  相似文献   
148.
Odor sensation is a sensory modality of considerable significance in the foraging behavior and interactional organization of ants. In the food bait technology, smell is the basis of attraction, which, in turn, is the line of bait use and a key parameter for judging efficacy. Yet, the currently available baits possess low attractiveness to many ant pests. Hence, strategies to produce ant bait with increased attractiveness are needed. Despite evidence that coffee has a diverse aroma complex that affects the behavior of honey bees and ants, its attraction to house-invading ants has yet to be investigated. In a series of Y-tube olfactometer bioassays, we examined the behavioral responses of Tapinoma indicum (TI), Monomorium pharaonis (MP) and Solenopsis geminata (SG) to various coffee-induced odor stimuli, comprised of extracts from Arabica, Robusta and Liberica. All coffee extracts showed an influence on the behavior of TI, MP and SG workers, with Arabica showed the most significant influence to the tested ants. The workers of TI, MP and SG were more attracted to the odor of 0.01% Arabica extract (ONE), in comparison with 0.05% Arabica extract (TWO) or 0.10% Arabica extract (THREE). Arabica extract mixed with sugar (S) elicited a significant attraction from workers of all three species in a balanced competition with either unsweetened Arabica extract or water. These results indicated that coffee, particularly Arabica, was attractive to the foragers of TI, MP and SG, thus, the use of coffee as a novel stimulus agent seems plausible in ant bait development.  相似文献   
149.
The alpha-toxin is one of the virulence factors of Clostridium perfringens for gas gangrene in humans and animals or necrotic enteritis in poultry. The C-terminal domain of this toxin ( cpa 247-370 ) was synthesized and cloned into pT1NX vector to construct the pT1NX-alpha plasmid. This surface-expressing plasmid was electroporated into Lactobacillus casei ATCC 393, generating the recombinant L. casei strain expressing alpha-toxoid (LC-α strain). Expression of this modified alpha-toxoid was confirmed by SDS-PAGE, immunoblotting, and direct immunofluorescence microscopy. BALB/c mice, immunized orally by the recombinant LC-α strain, elicited mucosal and significantly humoral immune responses (p < 0.05) and developed a protection against 900 MLD/mL of the standard alpha-toxin. This study showed that this recombinant LC-α strain could be a promising vaccine candidate against gas gangrene and necrotic enteritis.  相似文献   
150.
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