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Li Li Osama Abdalla Abdelshafy Mohamad Jinbiao Ma Ariel D. Friel Yangui Su Yun Wang Zulpiya Musa Yonghong Liu Brian P. Hedlund Wenjun Li 《Antonie van Leeuwenhoek》2018,111(10):1735-1748
Little is known about the composition, diversity, and geographical distribution of bacterial communities associated with medicinal plants in arid lands. To address this, a collection of 116 endophytic bacteria were isolated from wild populations of the herb Glycyrrhiza uralensis Fisch (licorice) in Xinyuan, Gongliu, and Tekesi of Xinjiang Province, China, and identified based on their 16S rRNA gene sequences. The endophytes were highly diverse, including 20 genera and 35 species. The number of distinct bacterial genera obtained from root tissues was higher (n?=?14) compared to stem (n?=?9) and leaf (n?=?6) tissue. Geographically, the diversity of culturable endophytic genera was higher at the Tekesi (n?=?14) and Xinyuan (n?=?12) sites than the Gongliu site (n?=?4), reflecting the extremely low organic carbon content, high salinity, and low nutrient status of Gongliu soils. The endophytic bacteria exhibited a number of plant growth-promoting activities ex situ, including diazotrophy, phosphate and potassium solubilization, siderophore production, auxin synthesis, and production of hydrolytic enzymes. Twelve endophytes were selected based on their ex situ plant growth-promoting activities for growth chamber assays to test for their ability to promote growth of G. uralensis F. and Triticum aestivum (wheat) plants. Several strains belonging to the genera Bacillus (n?=?6) and Achromobacter (n?=?1) stimulated total biomass production in both G. uralensis and T. aestivum under low-nutrient conditions. This work is the first report on the isolation and characterization of endophytes associated with G. uralensis F. in arid lands. The results demonstrate the broad diversity of endophytes associated with wild licorice and suggest that some Bacillus strains may be promising candidates for biofertilizers to promote enhanced survival and growth of licorice and other valuable crops in arid environments. 相似文献
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Osama Omar Yousif Mea’ad Kadhum Hassan Lamia Mustafa Al-Naama 《Biological trace element research》2018,182(2):295-302
This study investigated neurotoxicity of chronic fluorosis in the rat hippocampus. Newly weaning, male, Sprague-Dawley (SD) rats were administered 15, 30, and 60 mg/L sodium fluoride (NaF) solution (fluorine ion concentration 8.25, 16.50, and 33.00 mg/L, respectively), and tap water, for 18 months. The neurotoxicological mechanism was examined with a focus on intracellular calcium overload. Results showed that as the fluoride concentration increased, calcium ion concentration [Ca2+], the expression of calcium/calmodulin-dependent protein kinase II α (CaMKIIα), and the expression of catus proto-oncogene protein c-fos (c-fos) all tend to increase. Compared to the control group, Ca2+, CaMKIIα, and c-fos significantly increased (P < 0.05) in the moderate-fluoride and the high-fluoride groups. These results indicate that Ca2+/CaMKIIα/c-fos channel signal may be the molecular mechanism of central nervous system damage caused by chronic fluoride intoxication. Moreover, elevated Ca2+ concentration in the hippocampus may be the initiating factor of neuronal apoptosis induced by fluoride. 相似文献
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Photophysical properties of hydroxyphenyl benzazoles and their applications as fluorescent probes to study local environment in DNA,protein and lipid
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Fluorescence techniques have drawn increasing attention because they provide crucial information about molecular interactions in protein–ligand systems beyond that obtained by other methods. The advantage of fluorescence spectroscopy stems from the fact that the majority of molecules in biological systems do not exhibit fluorescence, making fluorescent probes useful with high sensitivity. Also, the fluorescence emission is highly sensitive to the local environment, providing a valuable tool to investigate the nature of binding sites in macromolecules. In this review, we discuss some of the important applications of a class of molecules that have been used as fluorescent probes in a variety of studies. Hydroxyphenyl benzazoles (HBXs) show distinct spectroscopic features that make them suitable probes for the study of certain biological mechanisms in DNA, protein and lipid. In particular, the complex photophysics of 2‐(2′‐hydroxyphenyl)benzoxazole (HBO) and the distinguished fluorescence signatures of its different tautomeric forms make this molecule a useful probe in several applications. Among these are probing the DNA local environment, study of the flexibility and specificity of protein‐binding sites, and detecting the heterogeneity and ionization ability of the head groups of different lipidic phases. The spectroscopy of HBX molecules and some of their chemically modified structures is also reviewed. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Hany Ahmed Fouad Hosam Mohamed Khalil Hammam El-Gepaly Osama Ahmed Fouad 《Archives Of Phytopathology And Plant Protection》2016,49(13-14):362-370
Recently, Tuta absoluta became one of the major pests that attack commercial tomato globally. Field test was done to evaluate the effect of different concentrations of nanosilica (NS) and jasmonic acid (JA), and compared them with indoxacrb (recommended insecticide) on reduction of damage rate caused by T. absoluta larvae under field conditions. Nanosilica (600 ppm) and indoxacrb (0.25 cm3/L) had the highest efficiency to reduce the rate of mines in the leaves. Jasmonic acid at rate 1.141 μM/plant showed a good reduction of number of fruits damaged. Nanosilica with 600 ppm concentration and Jasmonic acid at rate 1.141 μM/plant is used to control T. absoluta in the field. 相似文献
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Marie-Charlott Rümmler Osama Mustafa Jakob Maercker Hans-Ulrich Peter Jan Esefeld 《Polar Biology》2016,39(7):1329-1334
Unmanned aerial vehicles (UAVs) have become a useful tool in polar research. While their performance is already proven, little is known about their impact on wildlife. To assess the disturbance caused on the penguins, flights with a UAV were conducted over an Adélie penguin (Pygoscelis adeliae) colony. Vertical and horizontal flights were performed between 10 and 50 m in altitude. Penguins’ reactions were video-recorded, and the behavioural response was used to indicate the level of disturbance. During any flight mode, disturbance increased immediately after takeoff and remained elevated at all altitudes between 20 and 50 m. When the UAV descended below 20 m, the disturbance increased further with almost all individuals being vigilant. Only at these low altitudes, vertical flights caused an even higher level of disturbance than horizontal ones. Repetitions of horizontal overflights showed no short-term habituation occurring. Since the results are only valid for the specific UAV model used, we recommend a more extensive approach with different UAV specifications. As the highest flight altitudes already caused detectable but not subjectively visible responses, we also recommend to regard subjective impressions of disturbance with caution. 相似文献
59.
Nizar Haddad Ahmed Mahmud Batainh Osama Suleiman Migdadi Deepti Saini Venkatesh Krishnamurthy Sriram Parameswaran Zaid Alhamuri 《Insect Science》2016,23(4):579-590
Apis mellifera syriaca exhibits a high degree of tolerance to pests and pathogens including varroa mites. This native honey bee subspecies of Jordan expresses behavioral adaptations to high temperature and dry seasons typical of the region. However, persistent honey bee imports of commercial breeder lines are endangering local honey bee population. This study reports the use of next‐generation sequencing (NGS) technology to study the A. m. syriaca genome and to identify genetic factors possibly contributing toward mite resistance and other favorable traits. We obtained a total of 46.2 million raw reads by applying the NGS to sequence A. m. syriaca and used extensive bioinformatics approach to identify several candidate genes for Varroa mite resistance, behavioral and immune responses characteristic for these bees. As a part of characterizing the functional regulation of molecular genetic pathway, we have mapped the pathway genes potentially involved using information from Drosophila melanogaster and present possible functional changes implicated in responses to Varroa destructor mite infestation toward this. We performed in‐depth functional annotation methods to identify ~600 candidates that are relevant, genes involved in pathways such as microbial recognition and phagocytosis, peptidoglycan recognition protein family, Gram negative binding protein family, phagocytosis receptors, serpins, Toll signaling pathway, Imd pathway, Tnf, JAK‐STAT and MAPK pathway, heamatopioesis and cellular response pathways, antiviral, RNAi pathway, stress factors, etc. were selected. Finally, we have cataloged function‐specific polymorphisms between A. mellifera and A. m. syriaca that could give better understanding of varroa mite resistance mechanisms and assist in breeding. We have identified immune related embryonic development (Cactus, Relish, dorsal, Ank2, baz), Varroa hygiene (NorpA2, Zasp, LanA, gasp, impl3) and Varroa resistance (Pug, pcmt, elk, elf3‐s10, Dscam2, Dhc64C, gro, futsch) functional variations genes between A. mellifera and A. m. syriaca that could be used to develop an effective molecular tool for bee conservation and breeding programs to improve locally adapted strains such as syriaca and utilize their advantageous traits for the benefit of apiculture industry. 相似文献
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Utilization of lipid-based drug delivery systems has recently gained focus for drugs characterized by poor aqueous solubility. The improved aqueous solubility overcomes one of the main barriers that limit their bioavailability. The objective of this work was to improve the solubility and oral bioavailability of Avanafil (AVA), a recently approved second generation type 5 phospodiesterase inhibitor used for erectile dysfunction.AVA was formulated as self-nanoemulsifying drug delivery system (SNEDDS) utilizing various oils, surfactants, and cosurfactants. The solubility of AVA in various oils, surfactants, and cosurfactants was determined. Ternary phase diagram was constructed to identify stable nanoemulsion region. The prepared AVA loaded SNEDDS were assessed for optical clarity, droplet size, conductivity, and stability studies. In vitro drug release and in vivo pharmacokinetic parameters using animal model were also investigated. Results revealed that stable AVA (SNEDDS) were successfully developed with a droplet size range of 65 to 190 nm. SNEDDS composed of 25% dill oil, 55% Tween 80, and 20% propylene glycol successfully improved solubilization of AVA (over 80% within 30 min) vis-a-vis the powder AVA (35% within 30 min). In vivo pharmacokinetic showed a significant (P < 0.05) increase in Cmax, reduction in Tmax, and SNEDDS enhanced the bioavailability in the rats by 1.4-fold when compared with pure drug.Key words: avanafil, erectile dysfunction, dill oil, self-nanoemulsifying, SNEDDS 相似文献