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251.
Several surface markers have been proposed for the identification and characterization of colorectal cancer stem-like cells (CR-CSLCs). However, their reliability in CR-CSLCs identification remains controversial. This study evaluated the correlation between all candidate surface marker's expression and CSLCs properties (tumorigenicity) through monitoring in vivo tumor incidence and final tumor volume. PubMed, Web of Science, and Scopus databases were systematically searched until November 2017. A total of 27 studies were found that met the inclusion criteria for cluster of differentiation 133 (CD133) and CD44 markers. Results indicated that either CD133 or CD44 positive cells caused about twofold increase in tumor volume compared with the negative cells (p < 0.05). In two groups of cells derived from primary tumors and cell lines, CD133 + cells had 25 and 1.45 times higher tumor incidence potential than CD133 cells, respectively ( p < 0.05). Also, cohort evaluation showed that CD133 overexpression at protein level is a marker of poor overall survival in colorectal cancer (CRC) patients. While CD44 + cells displayed twofold tumorigenicity compared with the negative cells ( p < 0.05), combination of CD44 and CD133 showed about sevenfold tumorigenicity potential ( p < 0.05). In conclusion, the present meta-analysis suggests that CD133 is a robust biomarker to identify primary tumor CSLCs and can be proposed as a prognostic marker of CRC patient whereas it should be used with caution in cell lines. It seems to be more reliable to use CD133 in combination with CD44 as target biomarkers for the isolation of CR-CSLCs in both cell line and primary tumor cells populations.  相似文献   
252.
Plant and Soil - Experimental data concerning possible trophic relationships between phorophytes and epiphytes are contradictory. Several studies have indirectly shown that epiphytes affect the...  相似文献   
253.
Our agricultural system and hence food security is threatened by combination of events, such as increasing population, the impacts of climate change, and the need to a more sustainable development. Evolutionary adaptation may help some species to overcome environmental changes through new selection pressures driven by climate change. However, success of evolutionary adaptation is dependent on various factors, one of which is the extent of genetic variation available within species. Genomic approaches provide an exceptional opportunity to identify genetic variation that can be employed in crop improvement programs. In this review, we illustrate some of the routinely used genomics‐based methods as well as recent breakthroughs, which facilitate assessment of genetic variation and discovery of adaptive genes in legumes. Although additional information is needed, the current utility of selection tools indicate a robust ability to utilize existing variation among legumes to address the challenges of climate uncertainty.  相似文献   
254.
A variety of epigenetic factors involved in leukemia pathogenesis. Among various epigenetic factors, microRNAs (miRNAs) have emerged as important players, which affect a sequence of cellular and molecular signaling pathways. Leukemia is known as progressive cancer, which is related to many health problems in the world. It has been shown that the destruction of the blood-forming organs could lead to abnormal effects on the proliferation and development of leukocytes and their precursors. Despite many attempts for approved effective and powerful therapies for patients with leukemia, finding and developing new therapeutic approaches are required. One of the important aspects of leukemia therapy, identification of underlying cellular and molecular mechanisms involved in the pathogenesis of leukemia. Several miRNAs (ie, miR-103, miR-101, mit-7, let-7i, miR-424, miR-27a, and miR-29c) and play major roles in response to therapy in patients with leukemia. miRNAs exert their effects by targeting a variety of targets, which are associated with response to therapy in patients with leukemia. It seems that more understanding about the roles of miRNAs in response to therapy in patients with leukemia could contribute to better treatment of patients with leukemia. Here, for the first time, we summarized various miRNAs, which are involved in response to therapy in the treatment patients with leukemia.  相似文献   
255.
Due to the increasing incidence of fungal opportunistic infections and emergence of antibiotic‐resistant fungal strains, antimicrobial peptides (AMPs) are considered as ideal candidates for antifungal compounds. In silico methods can reduce the limitations of natural AMPs such as toxicity and instability and improve their antimicrobial properties and selectivity. In this study, we designed AurH1, a new truncated peptide, based on the six‐amino acid sequence of Aurein1.2. Further , the antimicrobial activities and toxicity effects of AurH1 on human skin fibroblast cells and red blood cells were investigated. Finally, field emission scanning electron microscopy (FE‐SEM) and flow cytometry were performed in order to study the mechanism of action of AurH1. The results indicated that AurH1 had only antifungal activity (at a minimal inhibitory concentration (MIC) of 7.3‐125 μg/mL) without any antibacterial effects on the selected bacteria, while Aurein1.2 had both antifungal and antibacterial activities as positive control. Furthermore, AurH1 did not show any toxicity on Hu02 cells and human red blood cells at its MIC range. In conclusion, it became clear that AurH1 is a selective peptide against fungi with no toxic effects on the selected bacteria and human cells.  相似文献   
256.

Huntington disease (HD) is a progressive neurological disorder with dominant motor symptoms. It also has psychiatric manifestations, like anxiety and depression, that can emerge themselves before motor symptoms and impose a major burden on patients. Oxytocin (OXT) is a newly emerged treatment for disorders like autism and schizophrenia and recently is using to alleviate depression and anxiety. In the current study, we investigated the behavioral and molecular effects of OXT on the development of anxiety and depression in 3-nitropropionic acid (3-NP)-induced model of HD. Anxiety- and depression-like behaviors as well as the levels of oxytocin receptor (OXTR), metabotropic glutamate receptor (mGluR) 2, mGluR5, and glutathione (GSH) were measured in striatum, hippocampus, prefrontal cortex, and amygdala. Also, we questioned if sex had any modulatory effect. We found that 3-NP increased anxiety and depression compared to controls. It also reduced the levels of OXTR and mGluR2, increased mGluR5, and reduced GSH in studied brain regions. Pretreatment with OXT before the injection of 3-NP ameliorated anxiety and depression. Additionally, it protected the brain from developing low levels of OXTR, mGluR2, and GSH and high levels of mGluR5 in studied regions. The protective effects of OXT were similar between male and female animals. These data suggest that OXTR, mGluR2, mGluR5, and GSH may contribute to psychiatric manifestations of HD. In addition, pretreatment with OXT could prevent the mood changes in male and female rats.

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257.
Background

Continuing hyperglycemia causes and exacerbate oxidative stress. Betanin as the principal pigment of red beet root has antioxidant, anti-inflammatory, and anti-diabetic properties. The purpose of this study was to investigate the potency of betanin on antioxidant defense in STZ-induced diabetic rats’ livers.

Methods

STZ at a single dose of 60 mg/kg body weight was intraperitoneally injected and betanin (10, 20, and 40 mg/kg/day) was administered orally for 28 days. Malondialdehyde (MDA), total antioxidant capacity (TAC), protein carbonyl (PC) levels, and the enzyme activity of superoxide dismutase (SOD), catalases and glutathione peroxidases (GPx) were evaluated in the liver. Furthermore, gene expression of Nrf2 and mentioned antioxidant enzymes were measured by Real-time PCR.

Results

Betanin (10 and 20 mg/kg) significantly reduced PC levels and increased antioxidant enzyme activity in diabetic rats compared to the control diabetic group (P?<?0.01). In comparison to the diabetic control group, all studied genes expression in diabetic rats were increased significantly with betanin at doses of 10 and 20 mg/kg (P?<?0.02). The increase in gene expression at 20 mg/kg of betanin was significantly stronger than others (P?<?0.015) except for the catalase (P?=?0.201), that was almost the same. Moreover, treatment of diabetic rats with 20 mg/kg of betanin could significantly increase TAC levels (P?<?0.05) and decrease MDA levels (P?<?0.001) compared to diabetic control group.

Conclusions

Betanin could increase the antioxidant capacity of liver tissue associated with the Nrf2-mediated pathway in a dose-dependent manner.

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258.
259.
The production of carotenoids, lipid content, and fatty acid composition were all studied in a strain of Sporobolomyces ruberrimus when using different concentrations of technical glycerol as the carbon source and ammonium sulfate as the nitrogen source. The total lipids represented an average of 13% of the dry weight, and the maximum lipids were obtained when using 65.5 g/l technical glycerol (133.63 mg/ g). The optimal conditions for fatty acid production were at 27 degrees C using 20 g of ammonium sulfate and a pH range from 6 to 7, which produced a fatty acid yield of 32.5+/-1 mg/g, including 1.27+/- 0.15 mg of linolenic acid (LNA), 7.50+/-0.45 mg of linoleic acid (LLA), 5.50+/-0.35 mg of palmitic acid (PA), 0.60+/-0.03 mg of palmitoleic acid (PAL), 1.28+/-0.11 mg of stearic acid (SA), 9.09+/-0.22 mg of oleic acid, 2.50+/-0.10 mg of erucic acid (EA), and 4.25+/-0.20 mg of lignoceric acid (LCA), where the palmitic, oleic, and linoleic acids combined formed about 37% of the total fatty acids. The concentration of total carotenoids was 2.80 mg/g when using 20 g of ammonium sulfate, and consisted of torularhodin (2.70 mg/g) and beta-carotene (0.10 mg/ g), at 23 degrees C and pH 6. However, the highest amount with the maximum specific growth rate was obtained (micromax=0.096 h(-1)) with an ammonium sulfate concentration of 30 g/l.  相似文献   
260.
Although there are several computational models that explain the trajectory that cells take during migration, till now little attention has been paid to the integration of the cell migration in a multi-signaling system. With that aim, a generalized model of cell migration and cell-cell interaction under multisignal environments is presented herein. In this work we investigate the spatio-temporal cell-cell interaction problem induced by mechano-chemo-thermotactic cues. It is assumed that formation of a new focal adhesion generates traction forces proportional to the stresses transmitted by the cell to the extracellular matrix. The cell velocity and polarization direction are calculated based on the equilibrium of the effective forces associated to cell motility. It is also assumed that, in addition to mechanotaxis signals, chemotactic and thermotactic cues control the direction of the resultant traction force. This model enables predicting the trajectory of migrating cells as well as the spatial and temporal distributions of the net traction force and cell velocity. Results indicate that the tendency of the cells is firstly to reach each other and then migrate towards an imaginary equilibrium plane located near the source of the signal. The position of this plane is sensitive to the gradient slope and the corresponding efficient factors. The cells come into contact and separate several times during migration. Adding other cues to the substrate (such as chemotaxis and/or thermotaxis) delays that primary contact. Moreover, in all states, the average local velocity and the net traction force of the cells decrease while the cells approach the cues source. Our findings are qualitatively consistent with experimental observations reported in the related literature.  相似文献   
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