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21.
Linu Kuruvilla MB Mohamed Sathik Molly Thomas Lisha.P Luke Sumesh KV 《Journal of Crop Science and Biotechnology》2017,20(5):369-377
Cold stress is one of the major abiotic factors that influence the productivity and geographical distribution of many agriculturally important crops like Hevea brasiliensis. Cultivation of H. brasiliensis in India is being extended to northeastern regions, where low temperature during winter adversely affects its survival, growth, and productivity. Developing cold-tolerant genotypes is a primary requisite to maximize the productivity under such challenging environmental conditions. However, lack of methods for early evaluation of cold tolerance in the newly developed clones and the extensive time required for assessing their tolerance in the field are major constraints for clonal selection. The present study was initiated with an objective to identify and characterize cold stress responsive miRNAs from H. brasiliensis that show stronger association with cold tolerance. Next generation sequencing using Illumina HiSeq method revealed the expression of 21 and 29 conserved miRNA (from clone RRIM 600) families in cold-stressed and control samples, respectively. Forty-two novel miRNAs were identified from this study. Upon differential expression analysis, eight conserved miRNAs were found commonly expressed in both the samples. When expression analyses were performed subsequently with six selected miRNAs in two Hevea clones (viz. RRII 105 and RRIM 600), miR169 showed a strong association with cold tolerance. miRNAs such as miR482 and miR159 also exhibited association with cold tolerance. This study suggests the possibility of employing these miRNAs as markers for cold tolerance after validation in more number of genotypes with varying levels of cold tolerance. 相似文献
22.
Abdelhaleem Fahmy Salah Amin Ahmed Mostafa Basiouny Mohamed Elsayed Ibraheem Heba Fathy 《Journal of Soils and Sediments》2020,20(3):1742-1753
Journal of Soils and Sediments - Bedload transport discharge is important in river engineering and morphodynamics. The Meyer-Peter and Müller (MPM) equation for determining bedload transport... 相似文献
23.
Fahd M. Abdelkarem Mohamed E. Abouelela Mohamed R. Kamel Alaa M. Nafady Ahmed E. Allam Iman A. M. Abdel-Rahman Ahmad Almatroudi Faris Alrumaihi Khaled S. Allemailem Hamdy K. Assaf 《Marine drugs》2022,20(2)
Gorgostane steroids are isolated from marine organisms and consist of 30 carbon atoms with a characteristic cyclopropane moiety. From the pioneering results to the end of 2021, isolation, biosynthesis, and structural elucidation using 13C-NMR will be used. Overall, 75 compounds are categorized into five major groups: gorgost-5-ene, 5,6-epoxygorgostane, 5,6-dihydroxygorgostane, 9,11-secogorgostane, and 23-demethylgorgostane, in addition to miscellaneous gorgostane. The structural diversity, selectivity for marine organisms, and biological effects of gorgostane steroids have generated considerable interest in the field of drug discovery research. 相似文献
24.
Wei-wei ZHANG Xiao-ying ZHAN Shu-xiang ZHANG Khalid Hamdan Mohamed Ibrahima Ming-gang XU 《农业科学学报》2019,18(3):667-676
The concentration of soil Olsen-P is rapidly increasing in many parts of China, where P budget(P input minus P output) is the main factor influencing soil Olsen-P. Understanding the relationship between soil Olsen-P and P budget is useful in estimating soil Olsen-P content and conducting P management strategies. To address this, a long-term experiment(1991–2011) was performed on a fluvo-aquic soil in Beijing, China, where seven fertilization treatments were used to study the response of soil Olsen-P to P budget. The results showed that the relationship between the decrease in soil Olsen-P and P deficit could be simulated by a simple linear model. In treatments without P fertilization(CK, N, and NK), soil Olsen-P decreased by 2.4, 1.9, and 1.4 mg kg~(–1) for every 100 kg ha~(–1) of P deficit, respectively. Under conditions of P addition, the relationship between the increase in soil Olsen-P and P surplus could be divided into two stages. When P surplus was lower than the range of 729–884 kg ha~(–1), soil Olsen-P fluctuated over the course of the experimental period with chemical fertilizers(NP and NPK), and increased by 5.0 and 2.0 mg kg~(–1), respectively, when treated with chemical fertilizers combined with manure(NPKM and 1.5 NPKM) for every 100 kg ha~(–1) of P surplus. When P surplus was higher than the range of 729–884 kg ha~(–1), soil Olsen-P increased by 49.0 and 37.0 mg kg~(–1) in NPKM and 1.5 NPKM treatments, respectively, for every 100 kg ha~(–1) P surplus. The relationship between the increase in soil Olsen-P and P surplus could be simulated by two-segment linear models. The cumulative P budget at the turning point was defined as the "storage threshold" of a fluvo-aquic soil in Beijing, and the storage thresholds under NPKM and 1.5 NPKM were 729 and 884 kg ha~(–1)P for more adsorption sites. According to the critical soil P values(CPVs) and the relationship between soil Olsen-P and P budget, the quantity of P fertilizers for winter wheat could be increased and that of summer maize could be decreased based on the results of treatments in chemical fertilization. Additionally, when chemical fertilizers are combined with manures(NPKM and 1.5 NPKM), it could take approximately 9–11 years for soil Olsen-P to decrease to the critical soil P values of crops grown in the absence of P fertilizer. 相似文献
25.
Mai H. ElNaggar Ghada M. Abdelwahab Omnia Kutkat Mohamed GabAllah Mohamed A. Ali Mohamed E. A. El-Metwally Ahmed M. Sayed Usama Ramadan Abdelmohsen Ashraf T. Khalil 《Marine drugs》2022,20(3)
Several natural products recovered from a marine-derived Aspergillus niger were tested for their inhibitory activity against SARS CoV-2 in vitro. Aurasperone A (3) was found to inhibit SARS CoV-2 efficiently (IC50 = 12.25 µM) with comparable activity with the positive control remdesivir (IC50 = 10.11 µM). Aurasperone A exerted minimal cytotoxicity on Vero E6 cells (CC50 = 32.36 mM, SI = 2641.5) and it was found to be much safer than remdesivir (CC50 = 415.22 µM, SI = 41.07). To putatively highlight its molecular target, aurasperone A was subjected to molecular docking against several key-viral protein targets followed by a series of molecular dynamics-based in silico experiments that suggested Mpro to be its primary viral protein target. More potent anti-SARS CoV-2 Mpro inhibitors can be developed according to our findings presented in the present investigation. 相似文献
26.
Relative Prevalence of Antibiotic Resistance among Heterotrophic Bacteria from Natural and Culture Environments of Freshwater Prawn,Macrobrachium Rosenbergii
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Abdulla A. Mohamed Hatha A. Deborah Gnana Selvam Ambatt P Thomas 《Journal of the World Aquaculture Society》2016,47(4):470-480
As antibiotic residues and multidrug‐resistant (MDR) bacteria are of increasing concern to those involved in the seafood industry, there is an intense international focus to monitor MDR bacteria in seafood. There is also a trend to source seafood from organically raised farms in order to reduce antibiotic usage in culture operations. Hence this study was conducted to compare the antibiotic resistance among bacteria associated with various samples from the natural and culture environment of Macrobrachium rosenbergii. Samples from the natural environment included water, sediment, eggs, larvae, postlarvae (PL), feed items, and gut samples of M. rosenbergii and those from the culture environment were water, sediment, eggs, feed pellets, and gut samples of M. rosenbergii. Bacteria from water samples of natural and culture environments were frequently resistant to ampicillin, erythromycin, and penicillin, while more than 50% of the strains from sediment were resistant to erythromycin, nalidixic acid, and penicillin. Bacterial isolates from commercial feed had a relatively high degree of antibiotic resistance. Interestingly, occurrence of multiple drug resistance was higher among the bacteria associated with the samples from the natural environment of M. rosenbergii, pointing to more favorable selection pressure for drug resistant mutants in the natural environment. 相似文献
27.
Helena Khatoon Sanjoy Banerjee Fatimah Md Yusoff Mohamed Shariff 《Aquaculture Research》2010,41(9):1348-1355
Marine periphytic cyanobacteria and diatoms have been examined as a potential source of feed supplement for rearing aquatic larvae in the aquaculture industry. Culture of the periphytic diatom Amphora sp., Navicula sp., Cymbella sp. and the cyanobacteria Oscillatoria sp. at different salinities showed significant changes in biomass and specific growth rates. Diatoms growth was significantly higher at 35 g L−1, while for cyanobacteria growth was better at 25 g L−1. Significantly higher levels of protein and lipid were found in diatoms at low salinities (15–25 g L−1) and an increase in carbohydrate at high salinities (30–35 g L−1). Conversely, cyanobacteria showed a significantly higher lipid content at 30–35 g L−1 compared with other salinity levels but no significant changes were observed in the protein and carbohydrate contents at different salinity levels. The present findings can be taken into consideration when culturing marine periphytic Amphora sp., Navicula sp., Cymbella sp. and Oscillatoria sp. to provide appropriate levels of protein, lipid and carbohydrate as feed supplement as well as for bioremediation in aquaculture. 相似文献
28.
Mohamed Neji Mohamed Moncef Serbaji Olivier Hardy Mohamed Chaieb 《Arid Land Research and Management》2018,32(3):291-315
Knowledge about vegetation patterns along disturbance gradients is essential for conservation and management of coastal habitats in arid regions. This study focuses on the floristic diversity and the factors controlling the vegetation structure in the Gulf of Gabès (Tunisia). For this purpose, the floristic diversity of 120 relevés belonging to three coastal sites with different disturbance levels (40 relevés per site) was analyzed in relation with 10 environmental and anthropogenic factors. Therophytes constitute 54% of the 237 plants species belonging to 44 families identified in the present study. The species richness and floristic diversity indices exhibited a similar trend and peaked in the slightly disturbed site (H′?=?3.38; S?=?176). The similarity between sites was relatively low and reached its maximum between the little and the highly disturbed sites. Two-way indicator species analysis and detrended correspondence analysis applied on the floristic data resulted in groups mainly determined by disturbance level by explicitly segregating the three sites. Canonical correspondence analysis (CCA) indicated that the spatial pattern of species composition was mainly influenced by anthropogenic variables. Partial CCA revealed that the effect of anthropogenic variables on floristic composition was thrice higher than the effect of environmental variables (57.5% vs. 18.4%, respectively). Overall, this study provides a broad understanding of the floristic diversity and vascular plant richness in the Gulf of Gabès. The obtained results reflected a disturbance–diversity pattern and thus revealed the obvious importance of maintaining the intermediate disturbance for biodiversity conservation and monitoring. 相似文献
29.
Peixin YANG Mohamed S. MEDAN Koji Y. ARAI Wanzhu JIN Gen WATANABE Kazuyoshi TAYA 《Animal Science Journal》2005,76(5):427-434
The ontogeny of testicular inhibin/activin in ducks was investigated. Testicular localization of three inhibin/activin subunits (α, βA and βB) was determined in embryonic and newly hatched ducks from 12 days of incubation to 1 day of age, in immature ducks and in adult ducks. In the duck embryonic testis, positive α‐subunit immunostaining was first detected in the Leydig cells and Sertoli cells on day 15 of incubation, whereas βA‐subunit and βB‐subunit immunostaining were found in Sertoli cells and primary germ cells on day 18 of incubation. In 1 month old ducks, intense staining of α‐subunit was present in the seminiferous epithelium consistent with localization in Sertoli cells and primary germ cells, and the immunostaining of the βA‐ and βB‐subunit was also present in Sertoli cells and primary germ cells. Specific immunostaining with inhibin/activin α‐, βA‐ and βB‐subunits antisera occurred in Sertoli cells in the adult duck testes. In conclusion, it was shown that, in the duck testis, the majority of α‐, βA‐ and βB‐subunits are colocalized in Sertoli cells with a certain degree of staining in germ cells and the α‐subunit is present in Leydig cells of embryonic testes before day 18 of incubation. These results indicate that Sertoli cells and possibly germ cells in the embryonic testes of late stage of incubation and newly hatched ducks, immature ducks and mature ducks may produce bioactive inhibin dimers, inhibin A and inhibin B, as a possible regulator of follicle‐stimulating hormone secretion. Free inhibin/activin subunits and their dimers may also play an autocrine/paracrine role in the development of the testis and spermatogenesis. Furthermore, early onset of the α‐subunit in duck testes indicates that it may have an autocrine/paracrine effect on steroid hormones, which is important for sex differentiation. 相似文献
30.
Haematological estimations and serum biochemical analyses were made on 100 samples collected from clinically healthy Hijin racing camels (Camelus dromedarius) in Kuwait. The red blood cell counts, packed cell volume, haemoglobin concentration, mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration and total white blood cell counts were estimated. In the serum biochemical analyses, sodium, potassium, iron, calcium, phosphorus, magnesium, total bilirubin, blood urea nitrogen, creatinine, glucose, total protein and cholesterol concentrations were measured, as were the alanine aminotransferase, aspartate aminotransferase, -glutamyltransferase, creatine kinase and alkaline phosphatase activities. The results are discussed in relation to other findings reported in camels. 相似文献