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141.
Investigations were conducted using Helicoverpa armigera fed on transgenic tomato plants containing a synthetic Cry2ab gene aiming to evaluate its impact on the development of the predator Chrysoperla carnea. Prey consumption and development parameters of C. carnea were assessed. No obvious differences were observed in the development of C. carnea that preyed on H. armigera fed on transgenic Bt tomato plants as compared to the control. This shows obvious that transgenic Bt tomato plants can be safely used as an efficient tool for the biocontrol of H. armigera with no effect on its predator, C. carnea. 相似文献
142.
Elgamacy MA Shalaby RA Elkodsh AT Kamel AF Elsayed MS Abou-El-Ella DA 《Bioinformation》2011,7(2):52-58
We are reporting the discovery of small molecule inhibitors for vascular endothelial growth factor receptor type 2 (VEGFR-2) extracellular domain. The VEGFR-2 extracellular domain is responsible for the homo-dimerization process, which has been recently reported as a main step in VEGFR signal transduction cascade. This cascade is essential for the vascularization and survival of most types of cancers. Two main design strategies were used; Molecular docking-based Virtual Screening and Fragment Based Design (FBD). A virtual library of drug like compounds was screened using a cascade of docking techniques in order to discover an inhibitor that binds to this new binding site. Rapid docking methodology was used first to filter the large number of compounds followed by more accurate and slow ones. Fragment based molecular design was adopted afterwards due to unsatisfactory results of screening process. Screening and design process resulted in a group of inhibitors with superior binding energies exceeding that of the natural substrate. Molecular dynamics simulation was used to test the stability of binding of these inhibitors and finally the drug ability of these compounds was assisted using Lipinski rule of five. By this way the designed compounds have shown to possess high pharmacologic potential as novel anticancer agents. 相似文献
143.
Mohamed M.A. Amer Osama M. Salama Ferdinand Bohlmann Jürgen Ziesche 《Phytochemistry》1984,23(3):692-693
The roots of Urospermum picroides afforded urospermal A 15-O-β-d-glucoside. 相似文献
144.
Summary Southwest Western Australia has a particularly rich biodiversity. Clearing for agriculture has greatly reduced the extent of native vegetation in wheatbelt catchments; it also set into train hydrogeological and hydrological changes that are still evolving toward a new equilibrium. With those changes come widespread land salinization that presents a further risk to remnant vegetation, particularly in low portions of the landscape. The equilibrium position of shallow groundwater was modelled for the Blackwood Catchment, and used to assess the extent of risk to a set of remnant vegetation classes. A total of 37 368 ha of remnant vegetation was identified to be at risk of salinization when hydrological equilibrium is reached. Further hydrological modelling assessed the rate of development of these watertables (and hence the rate of impact on remnants), as well as the potential to protect remnants by controlling groundwater recharge with revegetation. The results demonstrate that only high levels of revegetation are effective at protecting high value remnants in the longer term. The timing of events is dependant on the accuracy of estimating recharge. 相似文献
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147.
Hany H. Arab Samir A. Salama Ahmed H. Eid Ahmed M. Kabel Nancy N. Shahin 《Journal of cellular physiology》2019,234(12):22424-22438
Excessive drinking of alcohol has been frequently associated with gastric injury; however, its underlying molecular mechanisms have been inadequately investigated. Methyl palmitate (MP) has demonstrated marked hepato-, cardio- and pulmonary protective features; however, its effects on ethanol-induced gastric injury have not been studied. The aim of the present study was to evaluate the potential gastroprotective activity of MP against ethanol-evoked gastric mucosal damage in rats and associated molecular mechanisms, for example, mitogen-activated protein kinases (MAPKs), nuclear factor κB (NF-κB), and phosphoinositide 3 kinase/protein kinase B (PI3K/AKT) pathways. The rat stomachs were examined in terms of the inflammatory, oxidative, and apoptotic perturbations. Current data demonstrated that pretreatment with MP attenuated the gross gastric damage, scores of ulcer index, area of mucosal lesions and histopathology outcomes; actions which were similar to the reference antiulcer omeprazole. MP inhibited NF-κB expression, its nuclear translocation, and the expression of its downstream signals, for example, tumor necrosis factor-α and myeloperoxidase besides restoration of interleukin-10 levels. Western blot analysis revealed that MP counteracted the disruption of MAPKs signaling via lowering p-c-Jun N-terminal kinase 1/2 (p-JNK1/2) expression and restoring the phospho-extracellular signal-regulated kinase 1/2 (p-ERK1/2) levels without affecting p-p38MAPK levels. Additionally, MP improved the antioxidant milieu via diminishing lipid peroxides and enhancing glutathione, glutathione peroxidase, total antioxidant capacity and mucosal nitric oxide. In the context of apoptosis, MP inhibited the cleavage of caspase-3 and poly(ADP-ribose)polymerase (PARP) and Bax protein expression with upregulating B cell lymphoma-2 expression (Bcl-2), thus, promoting gastric cellular survival. This was confirmed by MP activation of the PI3K/AKT pathway manifested by enhanced expression of PI3K p110α and p-AKT. Together, the present findings report the gastroprotective actions of MP mediated via its anti-inflammatory, antioxidant, and antiapoptotic actions. The underlying molecular mechanisms involve, at least partly, the modulation of MAPKs, NF-κB and PI3K/AKT transduction. 相似文献
148.
Abd El-Halim A. Saad Fawzy M. A. Ragab Hesham M. Abdel Fatah Nevine K. Ibrahim 《Molluscan research.》2019,39(1):82-88
Controlling the snail intermediate host of schistosomiasis is one of the strategies used to reduce disease incidence. In this study screening tests were carried out on the action of dried powder of eight algal species against Biomphalaria alexandrina snails. The most effective powders were from Dictyota dichotoma and Cystoseira barbata with LC50 values of 560 and 2200?ppm, respectively. Prolonged exposure to sublethal concentrations of these two powders caused adverse effects on snails' reproduction especially at LC25. Hatchability of exposed eggs was lowest at LC25 of C. barbata, and LC15 of D. dichotoma. The most pronounced effects on the hermaphrodite gland of snails were caused by high concentrations of both algal suspensions, where ova were either degenerated or deformed and there were detrimental effects on all spermatogenesis stages. The electrophoretic separation of haemolymph proteins showed that the concentration with most effect was the LC15 for both tested algae as they resulted in more bands than the control and also an elevation in total protein content. 相似文献
149.
Manal Fawzy Amal M. Abdel-Rahman Gihan Hosny Balqees Raheem Odhafa 《International journal of phytoremediation》2019,21(12):1205-1214
AbstractIn this study, the techno-economic approach of olive leaves (Olea europaea L.) wastes for the removal of Cd2+ from aqueous solutions was demonstrated. The adsorption process was illustrated regarding batch experiments and scanning electron microscopy, energy dispersive X-ray, and Fourier-transform infrared characterization. The optimum pH and contact time were 6.6 and 123?min, respectively, giving Cd2+ removal efficiencies of 94.9% at Co = 50?mg/L and 81.5% at Co = 100?mg/L. The monolayer adsorption capacity of the Langmuir isotherm model was 32.6?mg/g (R2 = 0.97). The adsorption mechanisms might be related to (a) ion exchange with cations (e.g., K+, Na+, and Ca2+), (b) formation of cadmium chloride complexes, (c) interaction with oxygen-containing functional groups, (d) physical agglomeration in the pore surface, and (e) precipitation interaction using inorganic minerals (i.e., carbonates, phosphates, and silicates). The total cost of the adsorption process for the treatment of ions-containing wastewater was 0.038 $USD/m3. Assuming a benefit-cost of tertiary treated water as 0.044 $USD/m3, the adsorption system could attain a payback period of 5.7?years. This period was shorter than the lifetime of the capital investment (i.e., 10?years), and hence, the project would be economically feasible for an application. 相似文献