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71.
Serdar Korpayev Ayşe Karakeçili Hatice Dumanoğlu Salwa Ibrahim Ahmed Osman 《Biotechnology journal》2021,16(8):2100046
Nanocarriers for encapsulation and sustained release of agrochemicals such as auxins have emerged as an attractive strategy to provide enhanced bioavailability and efficacy for improved crop yields and nutrition quality. Here, a comparative study was conducted on the effectiveness of chitosan-as a biopolymeric nanocarrier- and silver-as a metallic nanocarrier- on in vitro adventitious rooting potential of microcuttings in apple rootstocks, for the first time. Auxins indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) loaded silver (nAg) or chitosan nanoparticles (nChi) were synthesized. Scanning electron microscopy and transmission electron microscopy studies showed the spherical shape of the nanoparticles. The average particle size of IAA-nChi was 167.5 ± 0.1 nm while that of IBA-nChi was 123.2 ± 2.6 nm. The hydrodynamic diameter of the nAg-IAA and nAg-IBA particles were measured as 93.66 ± 5 nm and 71.41 ± 3 nm, respectively. Fourier transform infrared spectroscopy analyses confirmed the encapsulation of IAA or IBA in the chitosan nanoparticles. Meanwhile, the characteristic peaks of IAA or IBA were detected on silver nanoparticles. In-vitro adventitious rooting of microcuttings of Malling Merton 106 (MM 106) was significantly higher both in chitosan and silver nanoparticles loaded with IAA or IBA (91.7%–62.5%) compared to free IAA or IBA applications (50.0%–33.3%), except for 2.0 mg L–1 IBA (66.7%). However, the application of 2 mg L–1 IBA and IBA-nChi at all concentrations caused an undesirable large callus development. 相似文献
72.
Tarek S. Ibrahim Amr H. Moustafa Ahmad J. Almalki Rasha M. Allam Abdulhamid Althagafi Shadab Md Mamdouh F. A. Mohamed 《Journal of enzyme inhibition and medicinal chemistry》2021,36(1):1067
Two series of chalcone/aryl carboximidamide hybrids 4a–f and 6a–f were synthesised and evaluated for their inhibitory activity against iNOS and PGE2. The most potent derivatives were further checked for their in vivo anti-inflammatory activity utilising carrageenan-induced rat paw oedema model. Compounds 4c, 4d, 6c and 6d were proved to be the most effective inhibitors of PGE2, LPS-induced NO production, iNOS activity. Moreover, 4c, 4d, 6c and 6d showed significant oedema inhibition ranging from 62.21% to 78.51%, compared to indomethacin (56.27 ± 2.14%) and celecoxib (12.32%). Additionally, 4c, 6a and 6e displayed good COX2 inhibitory activity while 4c, 6a and 6c exhibited the highest 5LOX inhibitory activity. Compounds 4c, 4d, 6c and 6d fit nicely into the pocket of iNOS protein (PDB ID: 1r35) via the important amino acid residues. Prediction of physicochemical parameters exhibited that 4c, 4d, 6c and 6d had acceptable physicochemical parameters and drug-likeness. The results indicated that chalcone/aryl carboximidamides 4c, 4d, 6c and 6d, in particular 4d and 6d, could be used as promising lead candidates as potent anti-inflammatory agents. 相似文献
73.
Irum Sidra Andleeb Saadia Ali Amjad Rashid Muhammad Ibrahim Majid Mahnoor 《International journal of peptide research and therapeutics》2021,27(4):2313-2331
International Journal of Peptide Research and Therapeutics - Pseudomonas aeruginosa (P. aeruginosa) is a critical healthcare challenge due to its ability to cause persistent infections and the... 相似文献
74.
75.
Nadia L. Radwan Waleed S. Mahmoud Rasha A. Mohamed Marwa M. Ibrahim 《Journal of musculoskeletal & neuronal interactions》2021,21(2):237
Objectives:The study aimed to determine the effect of adding a school-based plyometric training program (PMT) to physical education (PE) sessions on the strength, balance, and flexibility in primary school girls.Methods:Students from grades 3-6 were randomized equally to a plyometric or control group. In the control group, students took their regular PE classes twice a week. In the plyometric group, students performed PMT twice a week during the initial 20 minutes of every PE session. The Lido Linea closed kinetic chain isokinetic dynamometer, Star excursion balance test (SEBT), and sit-and-reach test were used to assess muscle strength, balance, and flexibility, respectively, before and after nine weeks of training.Results:The improvement in extension peak force (p=0.04) and extension total work (p<0.001) was more prevalent in the PMT group than in the control group. SEBT scores had improved significantly (p<0.05) for all directions in the PMT group, except in the anterior direction, which was highly significant (p<0.001). Hamstring and lower back flexibility had improved more in the PMT group than in the control group (p<0.001).Conclusion:Adding PMT to regular PE classes has a positive and notable effect on muscle strength, balance, and flexibility in primary school students. 相似文献
76.
Enas A.A. Alabdali Hamed A. Ghramh Essam H. Ibrahim Zubair Ahmad Asma N. Asiri 《Saudi Journal of Biological Sciences》2021,28(4):2278-2284
Apis mellifera jemenitica incorporates a few perceived subspecies that vary in their natural properties and farming qualities. Mitochondrial COI gene sequence (mtCOI) has not been used before for bee identification in the southwestern region of Saudi Arabia. The aim of this work was to study the morphometry and analyzing the mtCOI of all collected bees. The nucleotide sequence of the mtCOI gene was analyzed. Similarity searches and distances between each obtained DNA and sequences available in GenBank were made. Morphometric analysis revealed close similarities among the studied bees, but these similarities are different from those previously indicated in earlier studies of the same region. Molecular studies revealed that the collected bees are similar to each other and some other sequences found in GenBank, but these bees are a new hybrid or subspecies that are different from those previously reported in the same region, indicating the emergence of a new hybrid. 相似文献
77.
78.
Mahamat Alhadj Moussa Ibrahim Judith Sophie Weber Sen Claudine Henriette Ngomtcho Djoukzoumka Signaboubo Petra Berger Hassane Mahamat Hassane Srge Kelm 《PLoS neglected tropical diseases》2021,15(6)
BackgroundAfrican trypanosomes are parasites mainly transmitted by tsetse flies. They cause trypanosomiasis in humans (HAT) and animals (AAT). In Chad, HAT/AAT are endemic. This study investigates the diversity and distribution of trypanosomes in Mandoul, an isolated area where a tsetse control campaign is ongoing, and Maro, an area bordering the Central African Republic (CAR) where the control had not started.Methods717 human and 540 cattle blood samples were collected, and 177 tsetse flies were caught. Trypanosomal DNA was detected using PCR targeting internal transcribed spacer 1 (ITS1) and glycosomal glyceraldehyde-3 phosphate dehydrogenase (gGAPDH), followed by amplicon sequencing.ResultsTrypanosomal DNA was identified in 14 human samples, 227 cattle samples, and in tsetse. Besides T. b. gambiense, T. congolense was detected in human in Maro. In Mandoul, DNA from an unknown Trypanosoma sp.-129-H was detected in a human with a history of a cured HAT infection and persisting symptoms. In cattle and tsetse samples from Maro, T. godfreyi and T. grayi were detected besides the known animal pathogens, in addition to T. theileri (in cattle) and T. simiae (in tsetse). Furthermore, in Maro, evidence for additional unknown trypanosomes was obtained in tsetse. In contrast, in the Mandoul area, only T. theileri, T. simiae, and T. vivax DNA was identified in cattle. Genetic diversity was most prominent in T. vivax and T. theileri.ConclusionTsetse control activities in Mandoul reduced the tsetse population and thus the pathogenic parasites. Nevertheless, T. theileri, T. vivax, and T. simiae are frequent in cattle suggesting transmission by other insect vectors. In contrast, in Maro, transhumance to/from Central African Republic and no tsetse control may have led to the high diversity and frequency of trypanosomes observed including HAT/AAT pathogenic species. Active HAT infections stress the need to enforce monitoring and control campaigns. Additionally, the diverse trypanosome species in humans and cattle indicate the necessity to investigate the infectivity of the unknown trypanosomes regarding their zoonotic potential. Finally, this study should be widened to other trypanosome hosts to capture the whole diversity of circulating trypanosomes. 相似文献
79.
Developing a safe and effective antiviral treatment takes a decade, however, when it comes to the coronavirus disease (COVID-19), time is a sensitive matter to slow the spread of the pandemic. Screening approved antiviral drugs against COVID-19 would speed the process of finding therapeutic treatment. The current study examines commercially approved drugs to repurpose them against COVID-19 virus main protease using structure-based in-silico screening. The main protease of the coronavirus is essential in the viral replication and is involved in polyprotein cleavage and immune regulation, making it an effective target when developing the treatment. A Number of approved antiviral drugs were tested against COVID-19 virus using molecular docking analysis by calculating the free natural affinity of the binding ligand to the active site pocket and the catalytic residues without forcing the docking of the ligand to active site. COVID-19 virus protease solved structure (PDB ID: 6LU7) is targeted by repurposed drugs. The molecular docking analysis results have shown that the binding of Remdesivir and Mycophenolic acid acyl glucuronide with the protein drug target has optimal binding features supporting that Remdesivir and Mycophenolic acid acyl glucuronide can be used as potential anti-viral treatment against COVID-19 disease. 相似文献
80.
Siva S. Panda Mohamed A. Ibrahim Said A. El‐Feky Alan R. Katritzky 《Journal of peptide science》2013,19(2):110-117
Nα‐Boc‐Nim‐(4‐toluenesulfonyl‐l ‐histidylbenzotriazole) enables convenient acylation of N‐, O‐, S‐, and C‐nucleophiles with no detectable racemization. We report efficient syntheses of novel histidine‐containing di‐, tri‐, and tetra‐peptides and models for the preparation of potentially biologically active histidine N‐, O‐, S‐, and C‐conjugates. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd. 相似文献