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211.
Sulla carnosa modulates root invertase activity in response to the inhibition of long‐distance sucrose transport under magnesium deficiency
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N. Farhat A. Smaoui L. Maurousset B. Porcheron R. Lemoine C. Abdelly M. Rabhi 《Plant biology (Stuttgart, Germany)》2016,18(6):1031-1037
- Being the principal product of photosynthesis, sucrose is involved in many metabolic processes in plants. As magnesium (Mg) is phloem mobile, an inverse relationship between Mg shortage and sugar accumulation in leaves is often observed.
- Mg deficiency effects on carbohydrate contents and invertase activities were determined in Sulla carnosa Desf. Plants were grown hydroponically at different Mg concentrations (0.00, 0.01, 0.05 and 1.50 mM Mg) for one month.
- Mineral analysis showed that Mg contents were drastically diminished in shoots and roots mainly at 0.01 and 0.00 mM Mg. This decline was adversely associated with a significant increase of sucrose, fructose and mainly glucose in shoots of plants exposed to severe deficiency. By contrast, sugar contents were severely reduced in roots of these plants indicating an alteration of carbohydrate partitioning between shoots and roots of Mg‐deficient plants. Cell wall invertase activity was highly enhanced in roots of Mg‐deficient plants, while the vacuolar invertase activity was reduced at 0.00 mM Mg. This decrease of vacuolar invertase activity may indicate the sensibility of roots to Mg starvation resulting from sucrose transport inhibition. 14CO2 labeling experiments were in accordance with these findings showing an inhibition of sucrose transport from source leaves to sink tissues (roots) under Mg depletion.
- The obtained results confirm previous findings about Mg involvement in photosynthate loading into phloem and add new insights into mechanisms evolved by S. carnosa to cope with Mg shortage in particular the increase of the activity of cell wall invertase.
212.
Amer M. Alanazi Alaa A.-M. Abdel-Aziz Taghreed Z. Shawer Rezk R. Ayyad Abdulrahman M. Al-Obaid Mohamed H. M. Al-Agamy 《Journal of enzyme inhibition and medicinal chemistry》2016,31(5):721-735
Some new derivatives of substituted-4(3H)-quinazolinones were synthesized and evaluated for their in vitro antitumor and antimicrobial activities. The results of this study demonstrated that compound 5 yielded selective activities toward NSC Lung Cancer EKVX cell line, Colon Cancer HCT-15 cell line and Breast Cancer MDA-MB-231/ATCC cell line, while NSC Lung Cancer EKVX cell line and CNS Cancer SF-295 cell line were sensitive to compound 8. Additionally, compounds 12 and 13 showed moderate effectiveness toward numerous cell lines belonging to different tumor subpanels. On the other hand, the results of antimicrobial screening revealed that compounds 1, 9 and 14 are the most active against Staphylococcus aureus ATCC 29213 with minimum inhibitory concentration (MIC) of 16, 32 and 32?μg/mL respectively, while compound 14 possessed antimicrobial activities against all tested strains with the lowest MIC compared with other tested compounds. In silico study, ADME-Tox prediction and molecular docking methodology were used to study the antitumor activity and to identify the structural features required for antitumor activity. 相似文献
213.
214.
Marwa Zayane Ameur Rahmouni Mejda Daami-Remadi Mohamed Ben Mansour Anis Romdhane 《Journal of enzyme inhibition and medicinal chemistry》2016,31(6):1566-1575
We designed and synthesized new series of diverse triazoles, isoxazoles, isoxazolines, and aziridines linked 4-methylumbelliferone 1 using intermolecular 1,3-dipolar cycloaddition reactions. Structures of these compounds were established on the basis of 1H NMR, 13C NMR, and ESI-HRMS. All prepared compounds were evaluated for their antimicrobial, anticoagulant, and anticholinesterase activities. Interestingly, among the tested molecules, some of the analogs displayed better activities than the parent 4-methylumbelliferone 1 such as 6a and 6d for their antifungal properties. Moreover, compounds 4, 5, 6, and 7 showed the importance of the added fragments to 4-methylumbelliferone 1 via the linker methylene to have good activity. 相似文献
215.
Rehab Mohammad Yusif Irhan Ibrahim Abu Hashim Elham Abdelmonem Mohamed Farid Abd-Elreheim Badria 《AAPS PharmSciTech》2016,17(2):328-338
Currently available anti-ulcer drugs suffer from serious side effects which limited their uses and prompted the need to search for a safe and efficient new anti-ulcer agent. Boswellia gum resin (BR) emerged as a safe, efficient, natural, and economic potential cytoprotective agent. Thus, it is of medical importance to develop gastroretentive (GR) formulations of BR to enhance its bioavailability and anti-ulcer efficacy. Early attempts involved the use of organic solvents and non-applicability to large-scale production. In this study, different tablet formulations were prepared by simple direct compression combining floating and bioadhesion mechanisms employing hydroxypropyl methylcellulose (HPMC), sodium carboxymethyl cellulose (SCMC), pectin (PC), and/or carbopol (CP) as bioadhesive polymers and sodium bicarbonate (SB) as a gas former. The prepared tablets were subjected for assessment of swelling, floating, bioadhesion, and drug release in 0.1 N HCl. The optimized GR formulation was examined for its protective effect on the gastric ulcer induced by indomethacin in albino rabbits compared with lactose tablets. The obtained results disclosed that swelling, floating, bioadhesion, and drug release of the GR tablets of BR depend mainly on the nature of the matrix and the ratio of polymer combinations. Moreover, a combination of SCMC-CP in a ratio of 2:1 (SCP21) exhibited desirable floating, bioadhesion, swelling, and extended drug release. Also, a 6-h pretreatment with SCP21 tablets decreased the severity of inflammation and number of bleeding spots among ulcer-induced rabbits in comparison to those treated with lactose tablets. 相似文献
216.
Mohammed Elmowafy Ahmed Samy Mohamed A. Raslan Ayman Salama Ragab A. Said Abdelaziz E. Abdelaziz Wafaa El-Eraky Sally El Awdan Tapani Viitala 《AAPS PharmSciTech》2016,17(3):663-672
Thymoquinone (TQ), obtained from black cumin (Nigella sativa), is a natural product with anti-oxidant, anti-inflammatory, and hepatoprotective effects but unfortunately with poor bioavailability. Aiming to improve its poor oral bioavailability, TQ-loaded nanostructured lipid carriers (NLCs) were prepared by high-speed homogenization followed by ultrasonication and evaluated in vitro. Bioavailability and pharmacodynamic studies were also performed. The resultant NLCs showed poor physical homogeneity in Compritol 888 ATO Pluronic F127 system which consequently produced larger particle size and polydispersity index, smaller zeta potential values, and lower short-term (30 days) physical stability than other systems. Encapsulation efficiency percentage (EE%) lied between 84.6?±?5% and 96.2?±?1.6%. TQ AUC0–t values were higher in animals treated with NLCs, with a relative bioavailability of 2.03- and 3.97-fold (for F9 and F12, respectively) higher than TQ suspension, indicating bioavailability enhancement by NLC formulation. Hepatoprotective effects of F12 showed significant (P?<?0.05) decrease in both serum alanine amino transferase and aspartate amino transferase to reach 305.0?±?24.88 and 304.7?±?23.55 U/ml, respectively, when compared with untreated toxic group. Anti-oxidant efficacy of F12 showed significant (P?<?0.05) decline of malondialdehyde and elevation of reduced glutatione. This improvement was also confirmed histopathologically. 相似文献
217.
Optimizing the spectrofluorimetric determination of cefdinir through a Taguchi experimental design approach
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Noura Hemdan Abou‐Taleb Dalia Rashad El‐Wasseef Dina Tawfik El‐Sherbiny Saadia Mohamed El‐Ashry 《Luminescence》2016,31(3):856-864
The aim of this work is to optimize a spectrofluorimetric method for the determination of cefdinir (CFN) using the Taguchi method. The proposed method is based on the oxidative coupling reaction of CFN and cerium(IV) sulfate. The quenching effect of CFN on the fluorescence of the produced cerous ions is measured at an emission wavelength (λem) of 358 nm after excitation (λex) at 301 nm. The Taguchi orthogonal array L9 (34) was designed to determine the optimum reaction conditions. The results were analyzed using the signal‐to‐noise (S/N) ratio and analysis of variance (ANOVA). The optimal experimental conditions obtained from this study were 1 mL of 0.2% MBTH, 0.4 mL of 0.25% Ce(IV), a reaction time of 10 min and methanol as the diluting solvent. The calibration plot displayed a good linear relationship over a range of 0.5–10.0 µg/mL. The proposed method was successfully applied to the determination of CFN in bulk powder and pharmaceutical dosage forms. The results are in good agreement with those obtained using the comparison method. Finally, the Taguchi method provided a systematic and efficient methodology for this optimization, with considerably less effort than would be required for other optimizations techniques. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
218.
Dario A. Breitel Louise Chappell-Maor Sagit Meir Irina Panizel Clara Pons Puig Yanwei Hao Tamar Yifhar Hagai Yasuor Mohamed Zouine Mondher Bouzayen Antonio Granell Richart Ilana Rogachev Asaph Aharoni 《PLoS genetics》2016,12(3)
The involvement of ethylene in fruit ripening is well documented, though knowledge regarding the crosstalk between ethylene and other hormones in ripening is lacking. We discovered that AUXIN RESPONSE FACTOR 2A (ARF2A), a recognized auxin signaling component, functions in the control of ripening. ARF2A expression is ripening regulated and reduced in the rin, nor and nr ripening mutants. It is also responsive to exogenous application of ethylene, auxin and abscisic acid (ABA). Over-expressing ARF2A in tomato resulted in blotchy ripening in which certain fruit regions turn red and possess accelerated ripening. ARF2A over-expressing fruit displayed early ethylene emission and ethylene signaling inhibition delayed their ripening phenotype, suggesting ethylene dependency. Both green and red fruit regions showed the induction of ethylene signaling components and master regulators of ripening. Comprehensive hormone profiling revealed that altered ARF2A expression in fruit significantly modified abscisates, cytokinins and salicylic acid while gibberellic acid and auxin metabolites were unaffected. Silencing of ARF2A further validated these observations as reducing ARF2A expression let to retarded fruit ripening, parthenocarpy and a disturbed hormonal profile. Finally, we show that ARF2A both homodimerizes and interacts with the ABA STRESS RIPENING (ASR1) protein, suggesting that ASR1 might be linking ABA and ethylene-dependent ripening. These results revealed that ARF2A interconnects signals of ethylene and additional hormones to co-ordinate the capacity of fruit tissue to initiate the complex ripening process. 相似文献
219.
Mohamed Boukhary Omar Cherif Ahmed N. El-Barkooky Samy A. Mohamed Yasmine Hussein-Kamel Daniel Girgis Hanna 《Historical Biology》2016,28(5):613-655
The stratigraphic framework of the Neogene sequence drilled by two offshore wells located in the north-eastern shore of the Nile Delta (the wells Sekhmet-1 and Sekhmet-2) has been established. The lithostratigraphic units with their sequences, from older to younger, are as follows: the Sidi Salim Formation (including Sr1 SB, Sr2 SB, Sr2 MFS, Sr3 SB and Sr3 MFS), a sequence representing the uppermost part of the Sidi Salim and most of the lower part of the Qawasim Formations (including Tor 1.1 SB, Tor 1.2 SB, Tor 1.3 SB, Tor 1.4 SB and ?Tor 2 SB), a sequence representing the uppermost part of Qawasim and the lower part of the Abu Madi Formations (including ?Me1 SB, Me2 SB and Me2 MFS), the Kafr El Sheikh Formation (including alternatively Za 1 and 2 SB and MFS and Ge 1 SB and MFS), the El Wastani Formation (including Ge 2 SB and MFS) and a Quaternary sequence represented by the topmost part of El Wastani and Mit Ghamr/Bilqas Formation (including alternatively ?Cala 1 and 2 SB and MFS and ?Io 2 SB). The lower part of the Qawasim in well Sekhmet-2 includes two LST: Tor 2 LST and Me 1 LST. 相似文献