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1.
Abstract

L-glutaminase from bacterial sources has been proven to be effective and economical agents in cancer therapy, food industry and high-value chemicals like threonine. In the present study, a newly isolated bacterial strain was potentially producing extracellular L-glutaminase, it identified as Bacillus subtilis OHEM11 (MK389501) using the 16S rRNA gene. L-glutaminase production optimized and the optimum factors for production under submerged fermentation were at pH 6.5–7.0 and 35?°C after 28?hr using rhamnose and glutamine as carbon and nitrogen sources, respectively, while bagasse was the best inducer for the production under solid-state fermentation. Ethanol precipitation and ion-exchange chromatography using QFF are the purification steps. L-glutaminase was purified to 2-fold with specific activity 89.78?U/mg and its molecular weight about 54.8?kDa with the alkaline property of the enzyme makes it clear having carcinostatic property; maximum enzyme activity at pH 8.2 and 40?°C and retained about 90% activity for 1?hr. The cytotoxicity effect of L-glutaminase indicated a significant safety on Vero cells with high anticancer activity against NFS-60, HepG-2, and MCF-7 cancer cell lines. The outcomes demonstrated that L-glutaminase could be applied in many biotechnological applications such as pharmaceutical and food processing.  相似文献   
2.
The efficacy of different concentrations of the commercial neem-based insecticide, Nimbicidine® and the ecdysone agonist compound Methoxyfenozide (RH-2485), was evaluated against larvae of Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae). RH-2485 and Nimbicidine® significantly (p?<?0.001) reduced adult longevity by 2.7 and 1.9 d at the higher concentrations tested, respectively, but no significant differences were observed at low concentration. The tested compounds strongly affected the reproduction of S. littoralis by producing a high percentage of sterility. Fecundity and fertility were significantly affected by both insecticides. No egg laying has been recorded with the higher concentration 0.5% of Nimbicidine® and 0.1?ppm of RH-2485, while no significant (p?>?0.05) difference was noticed on total number of eggs laid by the female when lower concentration 0.0001?ppm of RH-2485 was applied in the same stage as compared to the control. In the second part of this study, the invasion rate of Steinernema feltiae was affected by the addition of both Nimbicidine and RH-2485 to the diet of experimental host. At higher concentration of both compounds, the invasion rate was decreased despite the infection rate, while the percentage of invading nematodes increase to 56.7% with the combination treatment indicating a considerable improvement in the efficacy of S. feltiae nematode applied in combination with the lower concentration of Nimbicidine® over that of nematode alone. On the other hand, the invasion of S. feltiae to the insects that were fed on the diet with the addition of ecdyson compound was strongly decreased with increasing concentration of RH-2485 in host diet.  相似文献   
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ROR2 is a member of the cell surface receptor tyrosine kinase (RTKs) family of proteins and is involved in the developmental morphogenesis of the skeletal, cardiovascular and genital systems. Mutations in ROR2 have been shown to cause two distinct human disorders, autosomal recessive Robinow syndrome and dominantly inherited Brachydactyly type B. The recessive form of Robinow syndrome is a disorder caused by loss-of-function mutations whereas Brachydactyly type B is a dominant disease and is presumably caused by gain-of-function mutations in the same gene. We have previously established that all the missense mutations causing Robinow syndrome in ROR2 are retained in the endoplasmic reticulum and therefore concluded that their loss of function is due to a defect in their intracellular trafficking. These mutations were in the distal portion of the frizzled-like cysteine rich domain and kringle domain. Here we report the identification of two novel mutations in the frizzled-like cysteine-rich domain of ROR2 causing Robinow syndrome. We establish the retention of the mutated proteins in the endoplasmic reticulum of HeLa cells and therefore failure to reach the plasma membrane. The clustering of Robinow-causing mutations in the extracellular frizzled-like cysteine-rich domain of ROR2 suggests a stringent requirement for the correct folding of this domain prior to export of ROR2 from the endoplasmic reticulum to the plasma membrane. GenBank accession number ROR2, M97639.  相似文献   
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Non-alcoholic fatty liver disease (NAFLD) is a condition defined by significant lipid accumulation (5–10%) in hepatic tissue in the absence of significant chronic alcohol consumption. We aim to detect frequency of fatty liver among overweight/obese adults and children and associated clinical; anthropological measures; biochemical; genetic and imaging studies. Eighty three consecutive adults and 72 children included in the study. All patients underwent clinical measurements of height, body weight, body mass index (BMI), waist and hip circumference. Biochemical investigations were done to all subjects including liver function tests; lipid profile; fasting blood glucose; insulin resistance (IR); high sensitivity C reactive protein (hs-CRP); adiponectin and genotyping of adiponectin genes. Abdominal ultrasonography was done to search for fatty liver; to measure subcutaneous fat thickness (SFT) and visceral fat thickness (VFT). Fatty liver was detected in 47 (65.3%) children and in 52 (62.7%) adults. Correlation analysis in both groups revealed that enlarged liver was highly positively correlated to age; BMI, systolic blood pressure (SBP), diastolic blood pressure (DBP); waist circumference; hip circumference, subcutaneous fat thickness (SFT) and Visceral fat thickness (VFT), alanine aminotransferase (ALT), aspartate aminotransferase/alanine aminotransferase (AST/ALT). In addition in adults to fasting blood glucose, cholesterol, triglycerides (TG), low density lipoprotein (LDL), IR and hs-CRP. Homozygous T adiponectin genotype at position +276 was significantly increased among children with enlarged liver size and hs-CRP. NAFLD affects a substantial portion of adults and children; it is associated with the metabolic syndrome.  相似文献   
8.
Because nitrogen is considered to be the major growth-limiting element in boreal forests, the increasing nitrogen availability from deposition should lead to increasing growth. We have tested this assumption by simulating, with a simple model, carbon and nitrogen development in seven long-term fertilization experiments in three Nordic countries. The only differences between sites in the model are climate, the ambient nitrogen deposition, nitrogen fertilization regimes, and the initial conditions at the start of the experiment. The model simulates the observed stand development well as long as nitrogen remains the limiting factor. The simulated retention of deposited nitrogen is in general low (less than 50%), whereas retention of fertilizer nitrogen is higher. This seems to imply that the higher production in the fertilized stands will not be maintained once the fertilization is stopped. The model results also indicate that the major effect of climate on site productivity is through soil processes, not tree physiology.  相似文献   
9.
Developing effective stem cell-based therapies requires the design of complex in vitro culture systems for accurate representation of the physiological stem cell niche. Human amniotic membrane (hAM) has been successfully used in clinical grafting applications due to its unique biological and regenerative properties. Decellularized hAM (d-hAM) has been previously applied to the culture of human bone marrow mesenchymal stem cells (hMSCs), promoting their expansion and differentiation into adipogenic and osteogenic lineages. In the present study, hAM was decellularized by NaOH-treatment, to provide the three-dimensional (3D) bioscaffold for culturing hMSCs. The ultrastructural differences between intact hAM and decellularized hAM were characterized using the transmission electron microscope (TEM), as well as the 3D interaction between d-hAM and hMSCs cultured on the membrane. TEM examination of the intact hAM showed many microvilli on the epithelial layer cells, active Golgi apparatus, smooth endolplasmic reticulum and the characteristic pinocytic vesicles. The epithelial layer with its structures was absent in the d-hAM. However, no observable difference was detected in the ultrastructural characteristics of the compact stromal layer of d-hAM compared to intact hAM. Both contained bundles of extra cellular matrix (ECM) proteins, and scattered elastic fibres. Cultured human mesenchymal stem cells (hMSCs) examined by TEM appeared oval to spherical in shape and had a rough and non-uniform surface with distinct protrusions or irregular fillopodia. Their diameter ranged from 20.49 to 21.6 µm. Most of the cellular organelles were also noticed. SEM examination of the prepared samples revealed unique 3D interaction between the hMSC and d-hAM, where the latter seems to envelop the segments of the hMSCs lying on the surrounding membrane. This study shows that the decellularization process affected the epithelial layer only of hAM and had no effect on altering the presence of ECM components present in the stromal layer of the d-hAM. The interaction between hMSCs and d-hAM maybe mediated by hAM components other than human amniotic epithelial cells, such as ECM components or MSCs present in the deeper spongy layer of the membrane or/and the adhesive components of the basement membrane of the removed epithelial layer.  相似文献   
10.
Selective alkylation of dyphylline (1) with (2-acetoxyethoxy)methyl bromide (2a) or 4-acetoxybutyl bromide (2b) afforded 3'-O-[(acetoxyethoxy)methyl]dyphylline (3a) and 3'-O-(4-acetoxybutyl)-dyphylline (3b), respectively. A trans esterification process rather than alkylation of the dihydroxy-propyl side chain in 1 had taken place during the reaction with 2-p-toluoyloxy)ethyl chloride (5) to afford the respective 3'-toluoyloxy derivative 7 and not the anticipated 3'-O-[(p-toluoyloxy)ethyl]-dyphylline (6). Deacylation of 3a,b and 7 afforded 4a,b and 1, respectively. Viral screening of selected compounds against HBV has been investigated.  相似文献   
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