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971.
Banana is a tropical crop cultivated in warm places. Chilling stress in Egypt is making banana crops less
productive. Abscisic acid (ABA), a key plant hormone, regulates metabolic and physiological processes and
protects plants from a variety of stresses. In vitro growing banana shoots were pre-treated with ABA at four
concentrations (0, 25, 50, and 100 mM) and chilled at 5°C for 24 h, followed by a six-day recovery period at
25°C. By comparing ABA treatments to both positive and negative controls, physiological and biochemical
changes were investigated. Chilling stress (5°C) caused a considerable increase in lipid peroxidation and ion
leakage and reduced photosynthetic pigments in cold-treated plantlets. Increasing the concentration of ABA
to 100 µM enhanced the response to chilling stress. ABA had a major effect on mitigating chilling injury in
banana shoots by keeping cell membranes stable and lowering the amount of ion leakage and lipid peroxidation.
Also, ABA significantly maintained the photosynthetic pigment concentration of banana shoots; accumulated
higher amounts of total soluble carbohydrates and proline; and increased DPPH radical scavenging activity.
Furthermore, ABA treatment enhanced cold tolerance in chilling-stressed banana shoots through the regulation
of antioxidant enzyme activity. Overall, the results show that ABA is a good choice for protecting banana shoots
from the damage caused by chilling stress. 相似文献
972.
Yogesh Sutar Sunna Nabeela Shakti Singh Abdullah Alqarihi Norma Solis Teklegiorgis Ghebremariam Scott Filler Ashraf S. Ibrahim Abhijit Date Priya Uppuluri 《PLoS biology》2022,20(8)
Candida albicans biofilms are a complex multilayer community of cells that are resistant to almost all classes of antifungal drugs. The bottommost layers of biofilms experience nutrient limitation where C. albicans cells are required to respire. We previously reported that a protein Ndu1 is essential for Candida mitochondrial respiration; loss of NDU1 causes inability of C. albicans to grow on alternative carbon sources and triggers early biofilm detachment. Here, we screened a repurposed library of FDA-approved small molecule inhibitors to identify those that prevent NDU1-associated functions. We identified an antihelminthic drug, Niclosamide (NCL), which not only prevented growth on acetate, C. albicans hyphenation and early biofilm growth, but also completely disengaged fully grown biofilms of drug-resistant C. albicans and Candida auris from their growth surface. To overcome the suboptimal solubility and permeability of NCL that is well known to affect its in vivo efficacy, we developed NCL-encapsulated Eudragit EPO (an FDA-approved polymer) nanoparticles (NCL-EPO-NPs) with high niclosamide loading, which also provided long-term stability. The developed NCL-EPO-NPs completely penetrated mature biofilms and attained anti-biofilm activity at low microgram concentrations. NCL-EPO-NPs induced ROS activity in C. albicans and drastically reduced oxygen consumption rate in the fungus, similar to that seen in an NDU1 mutant. NCL-EPO-NPs also significantly abrogated mucocutaneous candidiasis by fluconazole-resistant strains of C. albicans, in mice models of oropharyngeal and vulvovaginal candidiasis. To our knowledge, this is the first study that targets biofilm detachment as a target to get rid of drug-resistant Candida biofilms and uses NPs of an FDA-approved nontoxic drug to improve biofilm penetrability and microbial killing.This study shows that encapsulation of the antiparasitic drug Niclosamide in nanoparticles can enhance its pharmaco-availability, prevent the growth and filamentation of Candida, and enhance biofilm penetrability and detachment, both in vitro and in two mouse models of mucosal candidiasis. 相似文献
973.
Eslam B. Elkaeed Mohammed S. Taghour Hazem A. Mahdy Wagdy M. Eldehna Nehal M. El-Deeb Ahmed M. Kenawy Bshra A. Alsfouk Mohammed A. Dahab Ahmed M. Metwaly Ibrahim H. Eissa Mohamed A. El-Zahabi 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):2191
New quinoline and isatin derivatives having the main characteristics of VEGFR-2 inhibitors was synthesised. The antiproliferative effects of these compounds were estimated against A549, Caco-2, HepG2, and MDA-MB-231. Compounds 13 and 14 showed comparable activities with doxorubicin against the Caco-2 cells. These compounds strongly inhibited VEGFR-2 kinase activity. The cytotoxic activities were evaluated against Vero cells. Compound 7 showed the highest value of safety and selectivity. Cell migration assay displayed the ability of compound 7 to prevent healing and migration abilities in the cancer cells. Furthermore, compound 7 induced apoptosis in Caco-2 through the expressive down-regulation of the apoptotic genes, Bcl2, Bcl-xl, and Survivin, and the upregulation of the TGF gene. Molecular docking against VEGFR-2 emerged the interactions of the synthesised compounds in a similar way to sorafenib. Additionally, seven molecular dynamics simulations studies were applied and confirmed the stability of compound 13 in the active pocket of VEGFR-2 over 100 ns. 相似文献
974.
In the literature, the periodontal tissue reaction to dissimilar occlusal stress has been described, including clinical and histologic changes caused by stresses in periodontal structures. With respect to occlusal forces, periodontal assembly demonstrates varying adaptive capacity from individual to individual and period to period within the same individual. Unfortunately, these occlusal stresses are yet to be quantified. As a result, determining the effect of normal occlusal force on periodontal elements in various angulations is of interest. Based on CBCT images, one FEA of the maxillary First molar was created, consisting of tooth pulp, periodontal ligament (PDL), and alveolar bone; the effect of normal occlusal force on the pdl in alternate angulations was assessed. Occlusion will occur at three contact areas representing the centric occlusion contact points, each of which will share a 150 N force. The analysis was performed for four force inclinations (0, 22.5°, 45°, and 90°). Maximum stresses are observed in cases of 90-degree loading. These stresses, however, are insignificant and will not cause the periodontal components to rupture. These tensile stresses, which are concentrated in the apical and cervical regions, may obstruct blood flow, resulting in tooth decay or, in some cases, periodontal breakdown in PDL. There have been attempts to express numerical data of stress to be provided for normal and hyper function loads to simulate occlusal situations at various angulations that are known to be accountable for healthy and diseased periodontium. 相似文献
975.
Storage of sequence data is a big concern as the amount of data generated is exponential in nature at several locations. Therefore,
there is a need to develop techniques to store data using compression algorithm. Here we describe optimal storage algorithm
(OPTSDNA) for storing large amount of DNA sequences of varying length. This paper provides performance analysis of optimal
storage algorithm (OPTSDNA) of a distributed bioinformatics computing system for analysis of DNA sequences. OPTSDNA
algorithm is used for storing various sizes of DNA sequences into database. DNA sequences of different lengths were stored by
using this algorithm. These input DNA sequences are varied in size from very small to very large. Storage size is calculated by this
algorithm. Response time is also calculated in this work. The efficiency and performance of the algorithm is high (in size calculation
with percentage) when compared with other known with sequential approach. 相似文献
976.
Mohamed El Sekily Sohila Mancy Ibrahim El Kholy El Sayed H. El Ashry Hassan S. El Khadem David L. Swartz 《Carbohydrate research》1977,59(1):141-149
L-threo-2,3-Hexodiulosono-1,4-lactone 2-phenylhydrazone(1) reacted with hydroxylamine to give the 3-oxime 2-phenylhydrazone(2). On boiling with acetic anhydride,2 was dehydrated to 4-[L-threo-2,3-diacetoxy-(1-hydroxypropyl)]-2-phenyl-1,2,3-triazole-5-car?ylic acid lactone(3), which was converted into 2-phenyl-4-(L-threo-1,2,3-trihydroxypropyl)-1,2,3-triazole-5-car?amide(4) with liquid ammonia. The structure of compound4 was confirmed by acetylation to 2-phenyl-4-(L-threo-1,2,3-triacetoxypropyl)-1,2,3-triazole-5-car?amide(5), and by periodate oxidation followed by reduction, to give 4-(hydroxymethyl)-2-phenyl-1,2,3-triazole-5-car?amide(6). Treatment of compound1 with aryl- or aroyl-hydrazines afforded mixed bishydrazones(7–14), which were acetylated to15–21, and treated with hydrazine to give pyrazolinediones22 and23 相似文献
977.
Nuha Elhassan Eyoab Iyasu Gebremeskel Mohamed Ali Elnour Dan Isabirye John Okello Ayman Hussien Dominic Kwiatksowski Jibril Hirbo Sara Tishkoff Muntaser E. Ibrahim 《PloS one》2014,9(5)
Human genetic variation particularly in Africa is still poorly understood. This is despite a consensus on the large African effective population size compared to populations from other continents. Based on sequencing of the mitochondrial Cytochrome C Oxidase subunit II (MT-CO2), and genome wide microsatellite data we observe evidence suggesting the effective size (Ne) of humans to be larger than the current estimates, with a foci of increased genetic diversity in east Africa, and a population size of east Africans being at least 2-6 fold larger than other populations. Both phylogenetic and network analysis indicate that east Africans possess more ancestral lineages in comparison to various continental populations placing them at the root of the human evolutionary tree. Our results also affirm east Africa as the likely spot from which migration towards Asia has taken place. The study reflects the spectacular level of sequence variation within east Africans in comparison to the global sample, and appeals for further studies that may contribute towards filling the existing gaps in the database. The implication of these data to current genomic research, as well as the need to carry out defined studies of human genetic variation that includes more African populations; particularly east Africans is paramount. 相似文献
978.
An Investigation of Wound Healing in Sugar Beet Roots Using Light and Fluorescence Microscopy 总被引:1,自引:1,他引:0
Following impact, wound healing was investigated in roots ofsugar beet using fluorescence microscopy in conjunction witha conventional lignin test. Samples of sugar beet roots wereharvested at different stages of development and impacted inthe laboratory with a falling bolt delivering 14 Joules.A response in the form of deposition of brown material, presumedto be melanin, along the outer and inner walls of cells at thewound surface was observed within 3 d of impact. This materialeventually became granular in appearance. Formation of a ligno-suberizedboundary layer from cells present at the time of impact firstoccurred in 16-week-old roots 9 d after impact. Intensity ofcalcofluor fluorescence supported the findings made using lightmicroscopy. As wound healing progressed with time, the intensityof calcofluor fluorescence declined, demonstrating interferenceby wound healing products with calcofluor binding. Aggressiveharvest and subsequent storage dramatically reduced calcofluorfluorescence indicating that this dye may have potential valuein the assessment of tissue damage. Copyright 2001 Annals ofBotany Company Sugar beet, wound healing, impact damage, bruising, fluorescence, calcofluor, lignin 相似文献
979.
Abdel-Fattah S.A. Saad Magdy A. Massoud Hala S. Ibrahim 《Archives Of Phytopathology And Plant Protection》2013,46(8):955-962
An experimental study was carried out in pots to investigate the activity of Nemathorin, natural product and biopesticides against root-knot nematodes (RKNs) on tomatoes. Fosthiazate and abamectin proved to be the most effective treatments which suppressed the RKN population by 82.1%. Furthermore, arbuscular mycorrhizal fungus 2 (AMF2) was the superior treatment that reduced galls/root system followed by abamectin with the values of 72.5% and 67.2%, respectively. In addition, fosthiazate, cadusafos and crustacean2 gave the highest increase in the root length with the values of 55.8%, 54.6% and 54.6%, respectively. AMF2 was the most effective treatment which increases the root weight by 43.9%, while azadirachtin decreased the rootweight by 12.2% compared to untreated check. AMF2, cadusafos and crustacean2 not only increased the shoot length but also increased the shoot weight. Azadirachtin recorded the minimum increase in shoot system length and weight. 相似文献
980.
Haque Ehfazul Bari Md. Sazzadul Khandokar Labony Anjum Juhaer Jantan Ibrahim Seidel Veronique Haque Md. Areeful 《Phytochemistry Reviews》2023,22(1):211-273
Phytochemistry Reviews - Tinospora crispa (L.) Hook. f. & Thomson (Menispermaceae) is a plant indigenous to Africa and South-East Asia. It is widely used in ethnomedicine to alleviate... 相似文献