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811.
812.
813.
Reham Hammad Mona Abd EL Rahman Eldosoky Shaimaa Hani Fouad Abdelaleem Elgendy Amany M Tawfeik Mohamed Alboraie Mariam Fathy Abdelmaksoud 《Innate immunity》2021,27(3):240
Cell destruction results in plasma accumulation of cell-free DNA (cfDNA). Dynamic changes in circulating lymphocytes are features of COVID-19. We aimed to investigate if cfDNA level can serve in stratification of COVID-19 patients, and if cfDNA level is associated with alterations in lymphocyte subsets and neutrophil-to-lymphocyte ratio (NLR). This cross-sectional comparative study enrolled 64 SARS-CoV-2-positive patients. Patients were subdivided to severe and non-severe groups. Plasma cfDNA concentration was determined by real-time quantitative PCR. Lymphocyte subsets were assessed by flow cytometry. There was significant increase in cfDNA among severe cases when compared with non-severe cases. cfDNA showed positive correlation with NLR and inverse correlation with T cell percentage. cfDNA positively correlated with ferritin and C-reactive protein. The output data of performed ROC curves to differentiate severe from non-severe cases revealed that cfDNA at cut-off ≥17.31 ng/µl and AUC of 0.96 yielded (93%) sensitivity and (73%) specificity. In summary, excessive release of cfDNA can serve as sensitive COVID-19 severity predictor. There is an association between cfDNA up-regulation and NLR up-regulation and T cell percentage down-regulation. cfDNA level can be used in stratification and personalized monitoring strategies in COVID-19 patients. 相似文献
814.
Sri Devi Sukumaran Shah Bakhtiar Nasir Jia Ti Tee Michael J. C. Buckle Rozana Othman Noorsaadah Abd. Rahman Vannajan Sanghiran Lee Syed Nasir Abbas Bukhari Chin Fei Chee 《Journal of enzyme inhibition and medicinal chemistry》2021,36(1):130
A series of C4-substituted tertiary nitrogen-bearing 2′-hydroxychalcones were designed and synthesised based on a previous mixed type acetylcholinesterase inhibitor. Majority of the 2′-hydroxychalcone analogues displayed a better inhibition against acetylcholinesterase (AChE) than butyrylcholinesterase (BuChE). Among them, compound 4c was identified as the most potent AChE inhibitor (IC50: 3.3 µM) and showed the highest selectivity for AChE over BuChE (ratio >30:1). Molecular docking studies suggested that compound 4c interacts with both the peripheral anionic site (PAS) and catalytic anionic site (CAS) regions of AChE. ADMET analysis confirmed the therapeutic potential of compound 4c based on its blood–brain barrier penetrating. Overall, the results suggest that this 2′-hydroxychalcone deserves further investigation into the therapeutic lead for Alzheimer’s disease (AD). 相似文献
815.
Abd El-Rahim M.A. El-Samawaty Deiaa A. El-Wakil Salman Alamery Mohamed M.H. Mahmoud 《Saudi Journal of Biological Sciences》2021,28(6):3294-3302
Antifungal activity of extracts of cinnamon (Cinnamomum zeylanicum), Cloves (Syzygium aromaticum), ginger (Zingiber officinale) and turmeric (Curcuma longa) were evaluated in vitro against 17 Penicillium spp. Seed disease and rotten fruit caused by these species cause considerable loss of quality for different agricultural products. Isolates of Penicillium spp. were screened for production of patulin an important serious mycotoxin. About 70.59% of Penicillium spp. produced this toxin in concentrations ranging from 4 to 31 ppb. The response of Penicillium spp.to plant extracts differed according to the plant extract and concentration. Cinnamon extract showed the greatest effect on P. asperosporum, P. aurintogriseum and P. brevicompactum, and cloves extract produced the greatest effect on P. chermesinum and P. duclauxii. Turmeric extract had less effect on P. duclauxii. Cloves extract was the most effective in reducing the growth of Penicillium spp. On the other hand, ginger extract with all concentrations used had less effect against most Penicillium spp in the laboratory. Plant extracts are promising as natural sources of environmentally friendly compounds in laboratory studies. 相似文献
816.
Fathia Abd Elwahid Mannaa Khaled Gamal El-Deen Abdel-Wahhab Eitedal Mahmoud Daoud Aliaa Abdel Rahman El Gendy Maha Mohamed Saber Nevein Naim Fadl 《Biochemistry and Biophysics Reports》2021
BackgroundPeripheral neuropathy (PN) is the damage and dysfunction of neurons of the peripheral nervous system. The present study was conducted to estimate the effectiveness of low-power laser therapy (LPLT) in the management of PN in a rats’ model.MethodsPN was induced by giving dichloroacetate (DCA) (250 mg/kg/day) for up to 12 weeks. Four groups of rats were used: control group, PN group, PN group treated with gabapentin and PN group treated with LPLT. The study was conducted for 8 weeks. The management of PN was estimated by behavioral tests which included hot plate and Morris water maze tests. Blood biochemical analysis were carried out.ResultsUsing of hot plate test indicated thermal hypoalgesia and using Morris water maze test showed cognitive decline in PN rats. Treatment with LPLT or gabapentin improved both the pain sensations and deteriorated memory that occurred in the PN rats. Biochemical analysis showed that LPLT significantly decreased the elevated beta-endorphin level in PN rats, while gabapentin could not reduce it. Treatment PN rats with LPLT or gabapentin shifted the high levels of TNF-α, IL-1β and IL-10 cytokines back to their normal values. Serum nitric oxide and MDA significantly increased in the PN group together with significant reduction in the rGSH level, these values were significantly improved by LPLT application while this was not the case with gabapentin treatment. Furthermore, treatment with gabapentin or LPLT significantly reduced serum ALAT and ASAT activities which are otherwise increased in the PN group. S100B, PGE2, total cholesterol, triglycerides, LDL-cholesterol, HDL-cholesterol, urea and creatinine showed insignificant changes among all groups.ConclusionsOur results showed that treatment with LPLT is more efficient than gabapentin in ameliorating the peripheral neuropathy induced by xenobiotics. 相似文献
817.
This work reports confirmation of the experimental assignment of the absolute-handedness chirality of single-walled carbon nanotubes (SWNTs). This was achieved by applying the scanning tunneling microscopy (STM) imaging technique to a supramolecular composite consisting of a metalized porphyrin derivative (nickel-5,15-bisdodecylporphyrin [Ni-BDP]) affixed to the surfaces of chiral-concentrated SWNTs (with right-handed helix P- and left-handed helix M- ). On the basis of the handedness chirality, different chiral supramolecular structures of Ni-BDP were observed on the surfaces of the two SWNT enantiomers. The incorporation of a metal center into the porphyrin ring did not significantly affect the SWNT absolute-handedness chirality assignment, the large pi-system porphyrin ring being the crucial factor. These findings will effectively pave the way towards the clear selective synthesis, separation, chemistry, and applications of SWNT enantiomers. 相似文献
818.
819.
Esraa E. Shalan Said S. Soliman Ahmed A. Mahmoud Jameel M. Al-Khayri Salha M. ALshamrani Fatmah A. Safhi Areej S. Jalal Diaa Abd El-Moneim Abdallah A. Hassanin 《Phyton》2023,92(7):2183-2196
Determination of the somaclonal variation of in vitro-propagated plants is crucial to determine the appropriate
micropropagation protocol and growth regulators for commercial scale multiplication. In this research, nine multiplication media (MM) augmented with different concentrations of 6-benzyl adenine (BA), Kinetin (Kin), and
Thidiazuron (TDZ), Three rooting media (RM) supplemented with three levels of α-naphthalene acetic acid
(NAA) and three types of soil mixtures (v/v); Coco peat/Vermiculite/Sand (CVS), Peat moss/Perlite/Sand
(PPS) and Peat moss/Perlite (PP) were used in the micropropagation protocol of daylily plants. MM2 showed
the maximum shoot length and the number of leaves, while MM9 showed the maximum number of shoots.
The RM1 showed the maximum root length and the number of roots. During acclimatization, CVS, PPS, and
PP soil mixture showed similar performance except the CVS mixture showed lower performance regarding plant
height and diameter. The genetic fidelity of micropropagated plants was evaluated using Start Codon Targeted
(SCoT) Markers. Six SCoT primers amplified 51 scorable bands with an approximate range from 146 bp to
1598 bp size. Thirty one out of 51 loci were presented in the mother plants. 40 loci were polymorphic, 11 were
monomorphic and 7 were unique. The amplification patterns of the micropropagated plants demonstrated genetic integrity to the mother plant ranging from 84.32 to 47.06 and somaclonal variations ranging from 52.94 with
5 mg/l BA pathway to 15.68 with 1mg/l TDZ pathway, thus demonstrating that the homogeneity and the variation of the micropropagated plants affected by the type and the quantity of the plant growth regulator used during
multiplication subcultures. This research can be successfully used for other ornamental and medicinal plants’ bulk
multiplication, germplasm conservation, and future genetic improvement. 相似文献
820.
Rania H. Abd El-Hameed Shahenda Mahgoub Hend M. El-Shanbaky Mosaad S. Mohamed Sahar A. Ali 《Journal of enzyme inhibition and medicinal chemistry》2021,36(1):977
Inflammation is associated with the development of several diseases comprising cancer and cardiovascular disease. Agents that suppress cyclooxygenase (COX) and lipoxygenase (LOX) enzymes, besides chemokines have been suggested to minimise inflammation. Here, a variety of novel heterocyclic and non-heterocyclic compounds were prepared from novel three furanone derivatives. The structures of all synthesised compounds were confirmed by elemental and spectral analysis including mass, IR, and 1H-NMR spectroscopy. Anti-inflammatory activities of these synthesised compounds were examined in vitro against COX enzymes, 15-LOX, and tumour necrosis factor-α (TNF-α), using inhibition screening assays. The majority of these derivatives showed significant to high activities, with three pyridazinone derivatives (5b, 8b, and 8c) being the most promising anti-inflammatory agents with dual COX-2/15-LOX inhibition activities along with high TNF-α inhibition activity. 相似文献