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981.
Mohamed M. Ali Kaouthar Jeddi Mohamed S. Attia Salah M. Elsayed Mohammad Yusuf Mahmoud S. Osman Mona H. Soliman Kamel Hessini 《Saudi Journal of Biological Sciences》2021,28(6):3204-3213
In the present study, ameliorative capabilities of wuxal amino (bio stimulant) under salt stress has been investigated through adaptive mechanisms and antioxidant potential in tomato plants. In the experiment, two different concentrations (2 cm L-1 and 3 cm L-1) of wuxal amino through foliar application and soil irrigation were applied to the salt (150 mM) treated tomato plants and then morphological traits, photosynthetic pigments, osmolytes, secondary metabolites, oxidative stress and antioxidant enzymes activity were assessed at 60 days after planting. The results revealed that salt stress decreased the growth parameters, photosynthetic pigments, soluble sugars and soluble protein whereas, content of proline, ascorbic acid, total phenols, malondialdehyde, hydrogen peroxide and the activity of antioxidant enzymes activity increased under salt stress. Moreover, Wuxal amino application through foliar or soil to salt stressed plants improved morphological traits, photosynthetic pigments, osmolytes, total phenol and antioxidant enzymes activity. Interestingly, the deleterious impact of salinity on tomato plants were significantly reduced and it can be evident from reduced MDA and H2O2 levels. These responses varied with the mode (foliar or soil) of application of Wuxal amino under different concentrations (2 cm L-1 and 3 cm L-1). It was concluded that application of Wuxal amino (2 cm L-1, foliar) and (3 cm L-1; soil) proved best and could be commercially used as eco-friendly tool for the protection of tomato plants grown under salinity stress. 相似文献
982.
Effect of Shadowing on Survival of Bacteria under Conditions Simulating the Martian Atmosphere and UV Radiation 总被引:1,自引:0,他引:1
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Shariff Osman Zan Peeters Myron T. La Duc Rocco Mancinelli Pascale Ehrenfreund Kasthuri Venkateswaran 《Applied microbiology》2008,74(4):959-970
Spacecraft-associated spores and four non-spore-forming bacterial isolates were prepared in Atacama Desert soil suspensions and tested both in solution and in a desiccated state to elucidate the shadowing effect of soil particulates on bacterial survival under simulated Martian atmospheric and UV irradiation conditions. All non-spore-forming cells that were prepared in nutrient-depleted, 0.2-μm-filtered desert soil (DSE) microcosms and desiccated for 75 days on aluminum died, whereas cells prepared similarly in 60-μm-filtered desert soil (DS) microcosms survived such conditions. Among the bacterial cells tested, Microbacterium schleiferi and Arthrobacter sp. exhibited elevated resistance to 254-nm UV irradiation (low-pressure Hg lamp), and their survival indices were comparable to those of DS- and DSE-associated Bacillus pumilus spores. Desiccated DSE-associated spores survived exposure to full Martian UV irradiation (200 to 400 nm) for 5 min and were only slightly affected by Martian atmospheric conditions in the absence of UV irradiation. Although prolonged UV irradiation (5 min to 12 h) killed substantial portions of the spores in DSE microcosms (~5- to 6-log reduction with Martian UV irradiation), dramatic survival of spores was apparent in DS-spore microcosms. The survival of soil-associated wild-type spores under Martian conditions could have repercussions for forward contamination of extraterrestrial environments, especially Mars. 相似文献
983.
ŞEKER Perinçek Seçkinozan SELÇUK Ahmet Yesari SELVİ Engin BARAN Mehmet TEBER Saffet KELEŞ Gökçe Ali KEFELİOĞLU Haluk TEZ Coşkun İBİŞ Osman 《Organisms Diversity & Evolution》2022,22(3):821-841
Organisms Diversity & Evolution - The complete mitochondrial DNA (mitogenome) sequences of Chionomys nivalis and C. roberti were first presented as reference mitogenomes by the current study... 相似文献
984.
Bala K. Prabhala Nanda G. Aduri Johanne M. Jensen Heidi A. Ernst Nida Iram Moazur Rahman Osman Mirza 《FEBS letters》2014
Proton-coupled oligopeptide transporters (POTs) are secondary active transporters that facilitate di- and tripeptide uptake by coupling it to an inward directed proton electrochemical gradient. Here the substrate specificities of Escherichia coli POTs YdgR, YhiP and YjdL were investigated by means of a label free transport assay using the hydrophilic pH sensitive dye pyranine and POT overexpressing E. coli cells. The results confirm and extend the functional knowledge on E. coli POTs. In contrast to previous assumptions, alanine and trialanine appears to be substrates of YjdL, albeit poor compared to dipeptides. Similarly tetraalanine apparently is a substrate of both YdgR and YhiP. 相似文献
985.
Genetic analysis of Turkish martens: Do two species of the genus Martes occur in Anatolia?
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Stone marten (Martes foina) and European pine marten (M. martes) occur in western Eurasia. Current distributions of martens within Turkey and phylogenetic relationships among the Turkish and other populations of the two species within Eurasia remain relatively unknown. In this study, we aimed to determine genetic diversity within Martes populations inhabiting Turkey and to reveal the phylogenetic relationships among the Turkish and conspecific populations of the two marten species, using mitochondrial cytochrome b (CytB) sequences. Twenty‐four (24) haplotypes were identified among 86 marten samples collected across Turkey, including 23 novel haplotypes. Genetic distances among the Turkish haplotypes ranged from 0.1% to 0.8%, with an average of 0.3%. The 24 Turkish haplotypes were analysed together with those of conspecific populations deposited in GenBank. Phylogenetic (Bayesian Inference, maximum likelihood, neighbor‐joining) and network analyses revealed that all of the Turkish samples belonged to M. foina and that samples of M. martes were not encountered. Haplotypes of M. foina were divided into five haplogroups. The haplogroup including the two Chinese samples differed markedly from other the haplogroups. The remaining haplogroups contained samples from both the Turkish and European populations. We found that there was a genetically close relationship between the Turkish and the European stone marten populations. As a result of this study, M. martes may not be distributed in the Anatolian part of Turkey, possibly due to a barrier effect of two straits (Dardanelles and Bosporus) and the Caucasus Mountains. On the other hand, M. foina is distributed in both the Anatolian and Thracian parts of Turkey. Our results suggest that Turkey was likely one of the refuges for M. foina during Pleistocene glacial periods and is one of the centres of distribution of stone marten for Europe and the surrounding regions. 相似文献
986.
Baris Gungor Ahmet T. Alper Ahmet Celebi Osman Bolca 《Indian pacing and electrophysiology journal》2013,13(4):157-161
Left ventricular noncompaction (LVNC) is a genetically heterogenous form of cardiomyopathy which may remain undiagnosed till adulthood due to the late presentation of typical symptoms such as dyspnea, congestion, ventricular arrhythmias and thromboembolism. Symptomatic bradycardia secondary to persistent sinus node dysfunction is very rare. Coexistent cardiac defects are common in children however in adults the disease is usually in isolated form. Here, we present a case of twenty-three year-old female LVNC patient with patent ductus arteriosus, bicuspid aortic valve and persistent sinus node dysfunction who presented with dizziness as the first manifestation of the disease. 相似文献
987.
M Osman V Karcher-Djuricic J V Ruch 《Archives d'anatomie microscopique et de morphologie expérimentale》1977,66(2):109-118
The in vitro evolution of interspecific associations between pulps and enamel organs of embryonic Mouse and Rabbit tooth germs was studied. It was shown that young pulps controlled the three-dimensional structure of tooth germs. It was also shown that dental papillae cells and dental epithelial cells, after monolayer culture, did not loose their respective ability to direct the histogenesis of teeth. 相似文献
988.
Hussein H. Abulreesh Gamal E. H. Osman Abdulrahman S. A. Assaeedi 《Indian journal of microbiology》2012,52(3):500-503
This study aimed at characterizing the insecticidal genes of eight Bacillus thuringiensis isolates that were recovered from the local environment of western Saudi Arabia. The screening for the presence of lepidopteran-specific cry1A family and vip3A genes, dipteran-specific cry4 family and coleopteran-specific cry3A, vip1A and vip2A genes, was carried out by PCR. All eight isolates produced PCR products that confirmed the presence of cry1Aa, cry1Ab, cry1Ac, cry4A, cry4B genes, but not cry3A, vip1A and vip2A genes. However, three isolates only were found to carry vip3A genes as revealed by PCR. The observation of cry1 and cry4 genes suggests that these eight isolates may have dual activity against Lepidoptera and Diptera species, while three isolates possessed vip3 genes in addition to cry1 and cry4 which suggests that these three isolates have toxic crystals and vegetative proteins. The results of this study are interesting in the sense that they may help developing new strategies for controlling insects of economic and medical importance in Saudi Arabia, using B. thuringiensis strains that naturally exist in the local environment instead of the current control strategies that are based solely on chemical insecticides. 相似文献
989.
Osman Mahgoub Hamza A. Babiker I.T. Kadim Mohammed Al‐Kindi Salwa Hassan W. Al‐Marzooqi Yasmin E. Eltahir M. A. Al‐Abri Aisha Al‐Khayat Kareema R. Al‐Sinani Homoud Hilal Al‐Khanjari Vânia Costa Shanyuan Chen Albano Beja‐Pereira 《Animal genetics》2013,44(3):336-339
Among all livestock species, cattle have a prominent status as they have contributed greatly to the economy, nutrition and culture from the beginning of farming societies until the present time. The origins and diversity of local cattle breeds have been widely assessed. However, there are still some regions for which very little of their local genetic resources is known. The present work aimed to estimate the genetic diversity and the origins of Omani cattle. Located in the south‐eastern corner of the Arabian Peninsula, close to the Near East, East Africa and the Indian subcontinent, the Sultanate of Oman occupies a key position, which may enable understanding cattle dispersal around the Indian Ocean. To disclose the origin of this cattle population, we used a set of 11 polymorphic microsatellites and 113 samples representing the European, African and Indian ancestry to compare with cattle from Oman. This study found a very heterogenic population with a markedly Bos indicus ancestry and with some degree of admixture with Bos taurus of African and Near East origin. 相似文献
990.
Esengul Karahisar Osman Tugay Ilkay Erdogan Orhan Fatma Sezer Senol Deniz Simon Vlad Luca Krystyna Skalicka‐Wozniak Mustafa Sahin 《化学与生物多样性》2019,16(9)
In the current study, the ethanol extracts of flower, stem, and root parts of two endemic Turkish species, e. g., Haplophyllum sahinii O. Tugay & D. Uluku? and H. vulcanicum Boiss . & Heldr ., were screened against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) associated with Alzheimer's disease as well as tyrosinase (TYR) linked to Parkinson's disease using ELISA microplate assay at 200 μg/mL. Among the extracts, the highest inhibition was caused by the stem extract of H. sahinii against BChE (IC50=64.93±1.38 μg/mL). Consistently, all of the extracts were found to exert a selective inhibition towards BChE to some extent. It was only the root extract of H. vulcanicum that could inhibit AChE at low level (IC50=203.18±5.33 μg/mL). None of the extracts displayed an inhibition over 50 % against TYR. Metabolite profiling of the extracts was achieved by a highly hyphenated liquid chromatographic mass spectrometric technique (HPLC‐DAD‐ESI‐Q‐TOF‐MS/MS), which revealed the presence of furoquinoline (β‐fagarine, γ‐fagarine) and amide (tubasenicine, tubacetine) alkaloids; furano‐ (rutamarin), pyrano‐ (xanthyletine), and geranyloxy coumarins; phenylpropanoid (secoisolariciresinol), arylnaphthalene (mono‐O‐acetyldiphyllin apioside), and dibenzylbutyrolactone (kusunokinin, haplomyrfolin) lignans. Several important differences were observed between the extracts analyzed. β‐Fagarine was the major alkaloid in H. vulcanicum, whereas γ‐fagarine was present only in the roots of both Haplophyllum species; moreover, secoisolariciresinol and secoisolariciresinol dimethyl ether were the main lignans in the stems and flowers. This is the first study identifying ChE and TYR inhibitory effect and metabolic profiles of H. vulcanicum and H. sahinii. 相似文献