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Development of multifunctional textile and clothing products with improved environmental profiles has been demanded both by textile industry and by consumer. Herein, dialdehyde sodium alginate (DASA) and dialdehyde carboxymethyl cellulose (DACMC) have been prepared, characterized and utilized, as an eco-friendly binding/ macromolecular crosslinking/hand building agents, in functional finishing of cellulose-containing fabrics. Fabric samples were treated with the nominated dialdehyde polysaccharide (DAPS, 10 g/l) along with the reactant resin (DMDHEU, 50 g/l), Ag- or TiO2-NPs as active ingredients (20 g/l) and ammonium persulfate catalyst (5 g/l) using the padding method. After functional finishing, the finished fabrics demonstrated a remarkable improvement in their antibacterial efficacy, UV-blocking ability, self-cleaning capacity, and surface roughness functionality without adversely affecting fabrics resiliency. The variation in these functional properties is affected by kind of DAPS, type of added nanoparticles as well as the treated substrate. Additionally, FTIR, SEM, EDS, and durability to wash measurements for selected samples were performed. Moreover, pre-oxidation of DAPS, functionalization reactions/interactions among the nominated reactants and the textile materials were also suggested.  相似文献   
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As a critical food crop, sweetpotato(Ipomoea batatas(L.) Lam.) is widely planted all over the world, but it is deeply affected by Sweetpotato Virus Disease(SPVD). The present study utilized short tandem target mimic(STTM) technology to effectively up-regulate the expression of laccase(Ib LACs) by successfully inhibiting the expression of mi R397. The upstream genes in the lignin synthesis pathway were widely up-regulated by feedback regulation, including phenylalanine ammonialyase(PAL), 4-coumar...  相似文献   
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Sarcophine derivatives have been suggested to be chemopreventive in nature. One of its derivatives, Sarcotriol (ST), was investigated to study the skin cancer chemopreventive effects in female CD-1 mice. Three groups (control, promotion, initiation) of 30 female CD-1 mice each were taken. Carcinogenesis was initiated with 7, 12- dimethylbenz (a) anthracene (DMBA) and promoted with 12-O-tetradecanoylphorbol-13- acetate (TPA). One hour before treating with DMBA (200 nmol/100 μl acetone), control and promotion groups were treated with acetone (100 μl) and initiation group with ST (30μg/100μl of acetone). Beginning one week after initiation with DMBA, control and initiation groups were treated with acetone and promotion group with ST (30μg/100μl of acetone), one hour before treating with TPA (5 nmol/100 μl acetone). This was carried out twice a week for the next 20 weeks. The effects of ST on 3H-thymidine incorporation in epidermal DNA, the possible role of apoptotic proteins and COX-2 involved in the prevention of skin tumor development of CD-1 mice were investigated. Tumor incidence and multiplicity was found to be 100%, 73%, 100% and 8.2, 4.8, 9.7 in control, promotion and initiation groups respectively. ST treatment resulted in a significant (P < 0.05) inhibition in the incorporation of 3H-thymidine in epidermal DNA. The promotion group showed higher levels of caspase-3, -8 and –9 compared to the control. COX-2 expression was significantly lower (P < 0.05) in the promotion group as compared to the control. No significant difference in caspase-3, -8, -9 and COX-2 levels were observed in the initiation group compared to control. Together, this study confirms the chemopreventive effects of ST, and for the first time identifies the stage of carcinogenesis at which ST exerts its chemopreventive effect, and elucidates the mechanism possibly by inducing apoptosis and decreasing the COX-2 levels, contributing to its overall cancer chemopreventive effects in the mouse skin cancer model.  相似文献   
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Transient regenerative potential of the neonatal mouse heart   总被引:2,自引:0,他引:2  
Certain fish and amphibians retain a robust capacity for cardiac regeneration throughout life, but the same is not true of the adult mammalian heart. Whether the capacity for cardiac regeneration is absent in mammals or whether it exists and is switched off early after birth has been unclear. We found that the hearts of 1-day-old neonatal mice can regenerate after partial surgical resection, but this capacity is lost by 7 days of age. This regenerative response in 1-day-old mice was characterized by cardiomyocyte proliferation with minimal hypertrophy or fibrosis, thereby distinguishing it from repair processes. Genetic fate mapping indicated that the majority of cardiomyocytes within the regenerated tissue originated from preexisting cardiomyocytes. Echocardiography performed 2 months after surgery revealed that the regenerated ventricular apex had normal systolic function. Thus, for a brief period after birth, the mammalian heart appears to have the capacity to regenerate.  相似文献   
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To assess the genetic diversity of Nile tilapia Oreochromis niloticus, a total of 250 fish from five Egyptian populations were genotyped using six microsatellite markers. Heterozygosity and Wright's F‐statistics (FIS, FST, and FIT) were calculated to determine the genetic variation within and between these populations. Observed heterozygosities were in the range of 0.4 (Burullus) to 0.96 (Qena), with FIS values ranging from 0.082 to 0.282. The mean FST showed that approximately 96.5% of the genetic variation was within‐population and 3.5% was among populations. Standard genetic distances were used to classify the five populations into two major groups. The deeper lotic river Nile populations of Assuit and Cairo formed one group and the shallow less lotic Delta lakes populations of Manzalla and Burullus formed the second group, with the upstream Nile Qena population being an outgroup. The findings from the current study help understanding of the broad‐scale population structuring of the Nile tilapia (O. niloticus) allowing the population groupings identified to act as potential sources of genetic variation. These populations could be included in future Marker‐Assisted‐Selection programs for economically desired production traits.  相似文献   
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Sarcophine-diol (SD) is a semi-synthetic derivative of sarcophine with a significant chemopreventive effect against non-melanoma skin cancer both in vitro and in vivo. Recently, we have studied the effect of SD on melanoma development using the mouse melanoma B16F10 cell line. In this study, our findings show that SD suppresses cell multiplication and diminishes membrane permeability for ethidium bromide (EB), a model marker used to measure cell permeability for Ca2+ ions. SD also decreases protein levels of COX-2, and increases degradation of phospholipases PLA2 and PLCγ1 and diminishes enzymatic activity of the Ca2+-dependent cPLA2. This lower membrane permeability for Ca2+-ions, associated with SD, is most likely due to the diminished content of lysophosphosphatidylcholine (lysoPC) within cell membranes caused by the effect of SD on PLA2. The decrease in diacylglycerol (DAG) and inositol 1,4,5-triphosphate (IP3) due to inhibition of PLCγ1, leads to the downregulation of Ca2+-dependent processes within the cell and also inhibits the formation of tumors. These findings support our previous data suggesting that SD may have significant potential in the treatment of melanoma.  相似文献   
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In this study, three molecular markers including random amplified polymorphic DNA (RAPD), inter simple sequence repeat (ISSR) and simple sequence repeat (SSR) were used to evaluate genetic variation of green tiger prawn Penaeus semisulcatus collected from two geographically isolated environments; located in the Manifa, Arabian Gulf, Saudi Arabia and Ataka, Suez Gulf, Egypt. Genetic parameters included the percentage of polymorphism (P%), effective alleles (Ne), Nei genetic diversity (H) and Shannon index (I), which were calculated based on molecular data. All three marker systems distinguished genetic variation of P. semisulcatus in various levels. The highest polymorphism (91.30%) was obtained with SSR, followed by ISSR (82.26%) and RAPD markers (62.04%), respectively. Our results indicate that SSR appeared to be the best suited molecular assay for assessing the genetic variation between genotypes of P. semisulcatus. The present study indicated that Manifa and Ataka genotypes were closely related. Moreover, the analysis of variability could require more than one DNA‐based molecular marker techniques.  相似文献   
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