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71.
Chondroitinase ABC I (cABC I) from Proteus vulgaris cleaves glycosaminoglycan chains which are responsible for most of the inhibition of axon regrowth in spinal cord injury. The clinical utilization of this enzyme is mainly limited by its thermal instability. This study has been undertaken to determine the effects of glycerol, sorbitol and trehalose on cABC I activity and thermal stability. The results indicated that the enzyme catalytic activity and intrinsic fluorescence intensity increased in the presence of these cosolvents whereas no considerable conformational changes observed in far-UV CD spectra. Thermal CD experiment revealed an increase in T(m) of cABC I in the presence of cosolvents which was significant for trehalose. Our results support the idea that cABC I has stabilized in the presence of glycerol, sorbitol and trehalose. Therefore, the use of these cosolvents seems to be promising for improvement in shelf-life and clinical applications of this drug enzyme.  相似文献   
72.
It is now well known that genetic and environmental factors affect the intestinal microbiome in an individual's lifetime and thus, different individuals possess different intestinal microbiomes and microbial metabolomes. The intestinal microbiome has been shown to differ among individuals from the same sex, between sexes and between individuals of different ages. Different families and, from a larger perspective, different communities, possess different microbiomes, and thus corresponding metagenomes. Therefore, it can be deduced that each individual human being can be characterized by his/her own intestinal microbial fingerprint. This understanding may prove helpful in future individualized medicine. These microorganisms are natural beneficial symbionts of the GI tract, have adapted to their human host over million years of coevolution and are now regarded as the second human genome. The difference in intestinal microbiome of different populations may explain why the results from different clinical trials on probiotic efficacy do not match with each other. People pay much, but they benefit little. In this article, it is recommended to isolate probiotics from natives' microbiomes and in the interest of efficacy, to use them in the same population. This line of thought can be considered in future guidelines from the Food and Agriculture Organization and the WHO on evaluation of probiotics in foods.  相似文献   
73.
The electrochemical behavior of insulin at glassy carbon (GC) electrode modified with nickel oxide nanoparticles and guanine was investigated. Cyclic voltammetry technique has been used for electrodeposition of nickel oxide nanoparticles (NiOx) and immobilization of guanine on the surface GC electrode. In comparison to glassy carbon electrode modified with nickel oxide nanoparticles and bare GC electrode modified with adsorbed guanine, the guanine/nickel oxide nanoparticles/modified GC electrode exhibited excellent catalytic activity for the oxidation of insulin in physiological pH solutions at reduced overpotential. The modified electrode was applied for insulin detection using cyclic voltammetry or hydrodynamic amperometry techniques. It was found that the calibration curve was linear up to 4muM with a detection limit of 22pM and sensitivity of 100.9pA/pM under the optimized condition for hydrodynamic amperometry using a rotating disk modified electrode. In comparison to other electrochemical insulin sensors, this sensor shows many advantages such as simple preparation method without using any special electron transfer mediator or specific reagent, high sensitivity, excellent catalytic activity at physiological pH values, short response time, long-term stability and remarkable antifouling property toward insulin and its oxidation product. Additionally, it is promising for the monitoring of insulin in chromatographic effluents.  相似文献   
74.
In the present work, the essential oils and volatiles from flowers, leaves, and stems of Salvia limbata obtained using microwave‐assisted hydrodistillation, solvent‐free microwave extraction, headspace‐assisted analysis, and headspace‐solid phase microextraction have been characterized for the first time. The results have been also compared with those from traditional separation techniques involving hydrodistillation and steam distillation. Regardless of some common compounds in all of the profiles, some dissimilarities were noted due to the use of different extracting approaches. Taking into account the chemical categories, sesquiterpene hydrocarbons were found as the most represented group of natural compounds contributing to the chemical profiles. It was also noted that the methanol extracts obtained from the flowers of Sallimbata showed a desirable antioxidant activity, comparable to the standard antioxidant butylated hydroxytoluene. Furthermore, using the disc diffusion and broth microdilution methods, all the tested bacteria demonstrated weak to moderate and moderate to strong sensibilities to the MeOH extracts obtained from different plant parts of Sallimbata.  相似文献   
75.
MicroRNAs, a class of gene expression regulatory non-coding RNAs, participate in the pathogenic mechanisms of gastric cancer which is one of the life-treating cancers. Due to its aberrant expression in some types of human cancer, miR-383 has the value of being investigated in relation to cancer treatment and diagnosis. MiR-383 is placed in intron of SGCZ, a protein-coding gene, which is subject to dysregulation in various diseases. The purpose of the current study was to investigate the contribution of miR-383 to intestinal-type gastric adenocarcinoma tumorigenesis. The expression level of miR-383 was investigated by qRT-PCR in pairs of tumorous and adjacent tumor-free tissues of 40 patients with gastric cancer during endoscopy. Also, the susceptibility of miR-383 as a tumor marker and the relationship between its aberrant expression and clinicopathological features were determined. qRT-PCR data showed that miR-383 was dysregulated during gastric tumorigenesis. MiR-383 was dramatically downregulated up to sevenfold in intestinal-type gastric adenocarcinoma compared with adjacent tumor-free tissues (P < 0.001). Misregulation of miR-383 did not reveal a significant correlation with clinical characteristics. The ROC area of 80% with 76% sensitivity and 84% specificity was determined by P < 0.001. The current study demonstrated downregulation of miR-383 in intestinal-type gastric adenocarcinoma. Downregulation of miR-383 might be used as a potential tumor marker for the diagnosis of gastric cancer or could be a potential target for gene therapy.  相似文献   
76.
We examined the effects of 2,4-epibrassinolide (EBR) application on photosynthesis, antioxidant enzyme activity, and Rubisco activase (RCA) gene expression in wheat (Triticum aestivum L.) seedlings under a combination of drought and heat stress. The net photosynthetic rates (Pn) of wheat seedlings decreased significantly, the photosynthetic capability was inhibited, and the activities of superoxide (SOD), peroxidase (POD), catalase (CAT), and RCA as well as the initial and total activity of Rubisco declined under the combined stress. These decreases and inhibitory effects were significantly ameliorated by exogenous EBR application. Three subunits (45–46, 41–42, and 38–39 kDa) of RCA were observed in wheat seedlings. The abundances of the 38–39 kDa and 41–42 kDa subunits were significantly lower in plants subjected to stressful conditions than in unstressed plants. Interestingly, a marked increase in 45–46 kDa RCA was observed under heat or heat combined with drought stress. The abundance of 38–39 kDa RCA in seedlings exposed to heat, drought, or their combination was significantly enhanced by EBR pretreatment, which paralleled the changes in initial Rubisco activity and Pn, but was not consistent with observed mRNA abundance. These results indicated that the larger subunit of RCA (45–46 kDa), which is more thermostable and increased in response to moderate heat stress, and the smaller isoform (38–39 kDa) of RCA may play important roles in maintaining the photosynthetic capability by EBR under stress conditions.  相似文献   
77.
Artificial neural networks (ANNs) have been widely used to solve the problems because of their reliable, robust, and salient characteristics in capturing the nonlinear relationships between variables in complex systems. In this study, ANN was applied for modeling of Chemical Oxygen Demand (COD) and biodegradable organic matter (BOD) removal from palm oil mill secondary effluent (POMSE) by vetiver system. The independent variable, including POMSE concentration, vetiver slips density, and removal time, has been considered as input parameters to optimize the network, while the removal percentage of COD and BOD were selected as output. To determine the number of hidden layer nodes, the root mean squared error of testing set was minimized, and the topologies of the algorithms were compared by coefficient of determination and absolute average deviation. The comparison indicated that the quick propagation (QP) algorithm had minimum root mean squared error and absolute average deviation, and maximum coefficient of determination. The importance values of the variables was included vetiver slips density with 42.41%, time with 29.8%, and the POMSE concentration with 27.79%, which showed none of them, is negligible. Results show that the ANN has great potential ability in prediction of COD and BOD removal from POMSE with residual standard error (RSE) of less than 0.45%.  相似文献   
78.
This research studied the use of constructed wetlands (CWs) to reduce water salinity. For this purpose, three halophytic species of the Chenopodiaceae family (Salicornia europaea, Salsola crassa, and Bienertia cycloptera) that are resistant to saline conditions were planted in the CWs, and experiments were conducted at three different salinity levels [electrical conductivity (EC)~2, 6, 10 dS/m]. EC and concentrations of calcium (Ca), magnesium (Mg), sodium (Na), and chlorine (Cl) were measured before and after phytoremediation with a retention time of 1 week. The results suggested that these plants were able to grow well and complete their life cycles at all the salinity levels within this study. Moreover, these plants reduced the measured parameters to acceptable levels. Therefore, these plants can be considered good options for salt phytoremediation.  相似文献   
79.
Dysregulation of neuronal Ca2+ and oxidative stress plays an important role in the activation of cysteine proteases including calpains and caspases that contribute to neuronal death. In neurodegenerative diseases, traumatic brain injury, stroke, and neuropathic pain calpain activities are markedly increased. Melatonin is a beneficial supplement in the treatment of central nervous system (CNS) disorders. Melatonin is a potent antioxidant and works as a free-radical scavenger to regulate a large number of molecular pathways, including oxidative stress, inflammation, apoptosis, and cell death under different pathological conditions. However, limited studies have evaluated the inhibitory effect of melatonin on calpains. This review summarizes the current knowledge related to the effects of melatonin on calpains in some of the common CNS disorders.  相似文献   
80.
Ticks are external parasitic arthropods that can transmit a variety of pathogens by sucking blood. Low-temperature tolerance is essential for ticks to survive during the cold winter. Exploring the protein regulation mechanism of low-temperature tolerance of Haemaphysalis longicornis could help to explain how ticks survive in winter. In this study, the quantitative proteomics of several tissues of H. longicornis exposed to low temperature were studied by data independent acquisition technology. Totals of 3 699, 3 422, and 1 958 proteins were identified in the salivary gland, midgut, and ovary, respectively. The proteins involved in energy metabolism, cell signal transduction, protein synthesis and repair, and cytoskeleton synthesis changed under low-temperature stress. The comprehensive analysis of the protein regulation of multiple tissues of female ticks exposed to low temperature showed that maintaining cell homeostasis, maintaining cell viability, and enhancing cell tolerance were the most important means for ticks to maintain vital signs under low temperature. The expression of proteins involved in and regulating the above cell activities was the key to the survival of ticks under low temperatures. Through the analysis of a large amount of data, we found that the expression levels of arylamine N-acetyltransferase, inositol polyphosphate multikinase, and dual-specificity phosphatase were up-regulated under low temperature. We speculated that they might have important significance in low-temperature tolerance. Then, we performed RNA interference on the mRNA of these 3 proteins, and the results showed that the ability of female ticks to tolerate low temperatures decreased significantly.  相似文献   
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