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11.
The study aims at performing a comparative assessment of two types of burn wound treatment. The present study was designed to prepare crosslinked and blended two natural polymers nanofiber scaffolds using gelatin (GE) and hyaluronic acid (HA). The GE/HA composite nanofibrous membranes with varied GE/HA weight ratio have also been successfully fabricated by an electrospinning method. The average diameter of GE/HA fibers was in the range of 20 to 150 nm. In vivo efficacy was also investigated based on a deep second degree burns model for Wistar rats. At 14 days post-operation, the dermal defect basically recovered its normal condition. A percentage of wound closure of GE/HA composite nanofibrous membranes and ChitoHeal gel reached up to 81.9 % and 77.8 % respectively, compared with 65 % of the untreated control (p<0.05). Also, histological parameters were assessed on postoperative day 7 and 14. The results of in vivo experiments showed that more epidermis was formed in the gel and scaffold groups compared to the control group. The numbers of inflammatory cells in these two groups were also smaller as compared with the control group, which could well be the reason for the delayed healing in the control group.  相似文献   
12.
The consequences of recurrent drought events compared with a single drought, and drought's interaction with deliberate selfing compared with open-pollination on postdrought recovery and persistence of smooth bromegrass, are not clear. This research was conducted to investigate the effects of recurrent drought stresses compared with a single drought on stress response, poststress recovery and persistence of full-sib and half-sib progenies of smooth bromegrass. During this study, 25 selfed (S1) and 25 open-pollinated (OP) progenies of smooth bromegrass created in 2012 were evaluated in the field under normal and recurrent drought stress during 2013–2016. After the first harvest of above-ground biomass in 2016, irrigation was withheld in both environments for 2 months; plants were subsequently re-watered and evaluated. Recurrent drought stress changed the relationships between different traits. Moreover, prolonged drought stress resulted in increased plant productivity (recovery aerial biomass; RABI) of S1 and OP populations in recurrent drought stress compared with normal environment. Mandatory selfing increased persistence of smooth bromegrass genotypes but did not affect recovery after prolonged drought stress. Results revealed that, selecting among S1 families would be more effective than OP ones.  相似文献   
13.
Background:TNBC is determined by the absence of ERBB2, estrogen and progesterone receptors’ expression. Cancer vaccines, as the novel immunotherapy strategies, have emerged as promising tools for treating the advanced stage of TNBC. The aim of this study was to evaluate CEA, MTDH, and MUC-1 proteins as vaccine candidates against TNBC. Methods:In this research, a novel vaccine was designed against TNBC by using different immunoinformatics and bioinformatics approaches. Effective immunodominant epitopes were chosen from three antigenic proteins, namely CEA, MTDH, and MUC-1. Recombinant TLR4 agonists were utilized as an adjuvant to stimulate immune responses. Following the selection of antigens and adjuvants, appropriate linkers were chosen to generate the final recombinant protein. To achieve an excellent 3D model, the best predicted 3D model was required to be refined and validated. To demonstrate whether the vaccine/TLR4 complex is stable or not, we performed docking analysis and dynamic molecular simulation. Result:Immunoinformatics and bioinformatics evaluations of the designed construct demonstrated that this vaccine candidate could effectively be used as a therapeutic armament against TNBC. Conclusion:Bioinformatics studies revealed that the designed vaccine has an acceptable quality. Investigating the effectiveness of this vaccine can be confirmed by supplementary in vitro and in vivo studies.Key Words: Adjuvants, Triple-negative breast cancer, Vaccine  相似文献   
14.
BACKGROUND: Knowledge of antimicrobial resistance patterns in E. coli, the predominant pathogen associated with urinary tract infections (UTI) is important as a guide in selecting empirical antimicrobial therapy. METHODS: To describe the antimicrobial susceptibility of E. coli associated with UTI in a major university hospital in Tehran (Iran), seventy-six clinical isolates of E. coli were studied for susceptibility to beta-lactam antibiotics by the disc diffusion method and Minimal Inhibitory Concentrations determination. RESULTS: All isolates were resistant to ampicillin, amoxicillin and oxacillin. Resistance to the other tested antibiotics was shown to be 93.4% to cefradine, 76.3% to carbenicillin, 47.3% to cefazoline, 50% to cefalexin and 32.8% to cephalothin while 1.3% expressed resistance to cefoxitime, and 2.6% were resistant to ceftizoxime and ceftriaxone. Two isolates (2.4%) harbored extended spectrum beta-lactamases (ESBL) shown by the double disc diffusion method. Substrate hydrolysis by ultra violet spectroscopy showed that 87.4% harbored penicillinases, 9% produced cephlosporinases and 3.6% degraded both substrates. Clavulanic acid inhibited enzyme activity in 82.9%, of which 78.95% was penicillinases (group IIa) and 3.95% was cephalosporinases (group IIb) of the Bush classification system. The rest of the isolates (6.58 %) were placed in group IV beta-lactamases. No group III beta-lactamase was found, as EDTA inhibited none of the enzymes. DNA amplification by polymerase chain reaction using specific primers for ampC, TEM and SHV type beta-lactamases for all of the isolates showed that 47 organisms (60%) carried the TEM gene and 18 isolates (24%) harbored blaTEM and ampC genes. About 26% of the organisms harbored SHV type enzymes. CONCLUSION: These results indicate that E. coli can posses a variety of beta-lactamases that are responsible for beta-lactam resistance.  相似文献   
15.
The processes of peanut maturation, curing, and roasting are known to have an important role in peanut flavors. One of these processes (i.e., roasting) has been found to have an effect on allergenicity. To determine if the other processes (i.e., maturation and curing) affect allergenicity, mature and immature roasted peanuts and peanuts cured at different temperatures (35-77 degrees C) were, respectively, tested for IgE binding and advanced glycation end adducts (AGEs). Peanuts with and without stress proteins, which are associated with peanut maturation and curing, were also tested. Results showed that mature roasted peanuts exhibited a higher IgE binding and AGEs level than immature roasted peanuts. Curing temperatures between 35 and 60 degrees C gave no difference in the profiles. However, a higher curing temperature (i.e., 77 degrees C) exhibited a profile of higher levels of AGEs and IgE binding. These levels were higher in peanuts with stress proteins than without stress proteins. Roasting increased stress protein level and IgE binding. From these results, the processes of maturation and curing, in conjunction with roasting, may be associated with allergenicity, suggesting that these processes may lead to changes in the allergenic properties of peanuts.  相似文献   
16.
Alfalfa is one of the most widely grown forage crops in Iran, especially in Shabestar county. Weeds play a significant role in reducing the feeding value of alfalfa. Weed survey was done in order to determine environmental factors on weed species distribution in alfalfa fields at Shabestar, Iran (2010–2011). The family dominance index (FDI) and relative dominance (RD) were used to find dominant families and species for infestation of Shabestar's alfalfa fields. Data were analyzed by principal component analysis (PCA) and canonical correspondence analysis (CCA). A total of 130 weed species belonging to 28 families were observed. The most dominant families, based on the FDI, were Asteraceae, Poaceae, and Brassicaceae with 66.3, 61.8, and 41.1 FDI, respectively. Alopecurus myosuroides and Convolvulus arvensis were the most dominant species according to the RD index, measuring 26.4 and 21.8, respectively. PCA showed that some weed species only infested specific areas, but a few species with broader environmental tolerances were found near origin. Most variation in species distribution was explained by altitude, which was followed by soil potassium and salinity content of the soil. Our results suggest that the effect of altitude was more important than other environmental factors.  相似文献   
17.
The plane tree is one of the most frequently used street trees in urban landscape in Iran and some Mediterranean countries and some age-old ones are found in these countries. Endophytes are microorganisms which associate with healthy plant tissues, persisting without causing diseases symptoms in the host and normally benefitting them through improving plant ability to withstand environmental stresses. In this contribution, the hypothesis of fungal endophytes existence in the plane trees as well as their relationship with morphological characteristics of trees and nutrient elements of leaves were studied in the central part of Iran. The experiment was performed according to an unbalanced completely randomized design. Approximate age and height of plane trees were recorded and then the greenness and visual appearance were evaluated. Healthy shoots and bark pieces were collected and surface sterilized then placed in petri dishes containing PDA. The results showed that endophytes frequency were significantly greater in age-old trees (60.04%) than young ones (39.96%). Endophytes existence had a positive correlation with iron (Fe) and potassium (K) concentrations of the leaves, and trees height and circumference. Also, there was a positive correlation between the presence of fungal endophytes and improved visual appearance of plane trees. The results suggest that fungal endophytes association enhanced nutrient elements assimilation in trees contributing at least partly to elevated survival of age-old plane trees.  相似文献   
18.
In order to reduce the damage caused by late-season drought stress of canola, a factorial split plot experiment was performed on the basis of the randomized complete blocks design with three replications in Karaj, Iran. The treatments were potassium sulfate in two levels, including application and non-application of potassium sulfate, irrigation at three levels including normal irrigation (control), restricted irrigation from the flowering and pod formation stage, as factorial were in main plots and winter canola cultivars including Opera, L72, KR1, GKH3705, GKH0224 were in subplots. The interaction effect of potassium sulfate?×?irrigation?×?cultivar on seed yield, stomatal resistance, oil yield, linoleic acid, linolenic acid and glucosinolate was significant at the 1% level. The promising line of L72 in normal irrigation and application of potassium sulfate and Opera cultivar under late-season drought stress and application of potassium sulfate had the highest seed yield, oil yield and fatty acids composition.  相似文献   
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20.
Peanut allergy is a public health issue. The culprits are the peanut allergens. Reducing the allergenic properties of these allergens or proteins will be beneficial to allergic individuals. In this study, the objective was to determine if peroxidase (POD), which catalyzes protein cross-linking, reduces the allergenic properties of peanut allergens. In the experiments, protein extracts from raw and roasted defatted peanut meals at pH 8 were incubated with and without POD in the presence of hydrogen peroxide at 37 degrees C for 60 min. The POD-treated and untreated samples were then analyzed by SDS-PAGE, western blots, and competitive inhibition ELISA. IgE binding or allergenicity was determined in blots and ELISA. Results showed that POD treatment had no effect on raw peanuts with respect to protein cross-linking. However, a significant decrease was seen in the levels of the major allergens, Ara h 1 and Ara h 2, in roasted peanuts after POD treatment. Also, polymers were formed. Despite this, a reduction in IgE binding was observed. It was concluded that POD induced the cross-linking of mainly Ara h 1 and Ara h 2 from roasted peanuts and that, due to POD treatment, IgE binding was reduced. The finding indicates that POD can help reduce the allergenic properties of roasted peanut allergens.  相似文献   
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