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171.
Eslam O. Osman David J. Smith Maren Ziegler Benjamin Kürten Constanze Conrad Khaled M. El‐Haddad Christian R. Voolstra David J. Suggett 《Global Change Biology》2018,24(2):e474-e484
Tropical reefs have been impacted by thermal anomalies caused by global warming that induced coral bleaching and mortality events globally. However, there have only been very few recordings of bleaching within the Red Sea despite covering a latitudinal range of 15° and consequently it has been considered a region that is less sensitive to thermal anomalies. We therefore examined historical patterns of sea surface temperature (SST) and associated anomalies (1982–2012) and compared warming trends with a unique compilation of corresponding coral bleaching records from throughout the region. These data indicated that the northern Red Sea has not experienced mass bleaching despite intensive Degree Heating Weeks (DHW) of >15°C‐weeks. Severe bleaching was restricted to the central and southern Red Sea where DHWs have been more frequent, but far less intense (DHWs <4°C‐weeks). A similar pattern was observed during the 2015–2016 El Niño event during which time corals in the northern Red Sea did not bleach despite high thermal stress (i.e. DHWs >8°C‐weeks), and bleaching was restricted to the central and southern Red Sea despite the lower thermal stress (DHWs < 8°C‐weeks). Heat stress assays carried out in the northern (Hurghada) and central (Thuwal) Red Sea on four key reef‐building species confirmed different regional thermal susceptibility, and that central Red Sea corals are more sensitive to thermal anomalies as compared to those from the north. Together, our data demonstrate that corals in the northern Red Sea have a much higher heat tolerance than their prevailing temperature regime would suggest. In contrast, corals from the central Red Sea are close to their thermal limits, which closely match the maximum annual water temperatures. The northern Red Sea harbours reef‐building corals that live well below their bleaching thresholds and thus we propose that the region represents a thermal refuge of global importance. 相似文献
172.
Zafar Rasheed Khaled Zedan Ghada Bin Saif Ragaa H. Salama Tarek Salem Ahmed A. Ahmed Alaa Abd El-Moniem Maha Elkholy Ahmad A. Al Robaee Abdullateef A. Alzolibani 《Clinical and molecular allergy : CMA》2018,16(1):23
Background
Allergic reactions have been implicated as contributions in a number of atopic disorders, including atopic dermatitis (AD), allergic rhinitis (AR) and bronchial asthma (BA). However, the potential for filaggrin protein, eosinophil major basic protein (MBP) and immunoglobulin E (IgE) to elicit allergic response or to contribute to atopic disorders remains largely unexplored in pediatric patients. This study was undertaken to investigate the status and contribution of filaggrin protein, eosinophil MBP and total IgE in pediatric patients with AD, AR and BA.Methods
Sera from 395 pediatric patients of AD, AR or BA with varying levels of disease activity according to the disease activity index and 410 age-matched non-atopic healthy controls were evaluated for serum levels of atopic markers, including filaggrin, eosinophil MBP and IgE.Results
Serum analysis showed that filaggrin levels were remarkably high in pediatric patients with AD, followed by BA and AR, whereas its levels were low in non-atopic pediatric controls. Eosinophil MBP levels in sera of atopic patients were significantly high as compared with their respective controls, but its levels were highest in AR patients, followed by AD and BA. Total IgE in sera of AD patients was markedly high, followed by AR and BA patients, whereas its levels were low in non-atopic pediatric controls. Interestingly, not only was an increased number of subjects positive for filaggrin protein, eosinophil MBP or total IgE, but also their levels were statistically significantly higher among those atopic patients whose disease activity scores were higher as compared with atopic patients with lower disease activity scores.Conclusions
These findings strongly support a role of filaggrin protein, eosinophil MBP and IgE in the onset of allergic reactions in pediatric patients with AD, AR and BA. The data suggest that filaggrin, eosinophil MBP or IgE might be useful in evaluating the progression of AD, AR or BA and in elucidating the mechanisms involved in the pathogenesis of these pediatric disorders.173.
Khaled Trabelsi Stephen R. Stannard Hamdi Chtourou Wacim Moalla Hanène Ghozzi Kamel Jamoussi 《Biological Rhythm Research》2018,49(3):337-365
During Ramadan, dehydration and disturbed sleep patterns are common, so accurate reliable methods for the assessment of hydration and sleep of athletes are necessary to maintain performance. The purpose of this review is: (1) to identify appropriate tools/methods for monitoring hydration status and sleep in sports people; (2) to discuss which of these tools/methods can be confidently used by sport scientists and trainers during Ramadan; and (3) to discuss the possible link that may exist between sleep and hydration status. Several markers of hydration status are currently used and include body mass, plasma/serum osmolality, dilution techniques, and neutron activation analysis. Used in an appropriate context, all can be indicative of the hydration status in the laboratory. In the field, monitoring hydration status in physically active individuals and athletes may be performed using a combination of body mass with some measure of urine concentration (e.g. urine osmolality, urine-specific gravity, urine color) and sensation of thirst. During Ramadan, appropriate timing of sample collection and the use of reference methods in future studies are warranted. In the field, careful use of body mass in conjunction with urine indices may be used to monitor the hydration status of subjects practicing physical activity during Ramadan. There is a need for the use of polysomnography or actigraphy for sleep assessment during Ramadan in future laboratory-based studies of athletes. However, in the field, monitoring sleep–wake patterns may be performed using actigraphy and/or the PSQI questionnaire. 相似文献
174.
Development of stability indicating HPLC method for the separation and validation of enantiomers of miconazole
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Nadia Bounoua Khaled Sekkoum Mehmet Gumustas Nasser Belboukhari Sibel A. Ozkan 《Chirality》2018,30(6):807-815
A selective and sensitive stability indicting HPLC method was developed for the analysis of enantiomers of miconazole. For this purpose, six different polysaccharide‐based chiral columns were evaluated. Optimization was performed using several polar organic and alcohol‐hydrocarbon mobile phases. As a result of optimization studies, the analysis was carried out using Lux Cellulose‐3, methanol as a mobile phase at a flow rate of 1 mL·min?1, and the detection wavelength was arranged to 230 nm. Developed method has been fully validated according to International Council on Harmonization guidelines. Method was found linear in the concentration range of 1 to 200 μg·mL?1. Coefficient of determination (R2) was calculated as 0.9996, intraday precision of the method was found with the RSD% of 0.56, and the recovery of the method was calculated close to 100%. Furthermore, some other validation parameters like specificity, selectivity, LOD, and LOQ were also investigated. Stability indicating capability of this method was shown by forced degradation studies, and the run time for each analysis was less than 6 minutes. As a result, simple, fast, reliable HPLC method was developed for the separation and determination of the enantiomers of miconazole. Applicability of the developed method was shown with the application of marketed pharmaceutical preparations. 相似文献
175.
Khaled Abdou Frida Ben Rais Lasram Mohamed Salah Romdhane François Le Loc’h Joël Aubin 《The International Journal of Life Cycle Assessment》2018,23(5):1049-1062
Purpose
The present study aims to understand the influence of rearing practices and the contributions of production phases of fish farming to their environmental impacts and determine which practices and technical characteristics can best improve the farms’ environmental performance. Another objective is to identify the influence of variability in farming practices on the environmental performances of sea cage aquaculture farms of sea bass and sea bream in Tunisia by using principal component analysis (PCA) and hierarchical clustering on principal components (HCPC) methods and then combining the classification with life cycle assessment (LCA).Methods
The approach consisted of three major steps: (i) of the 24 aquaculture farms in Tunisia, 18 were selected which follow intensive rearing practices in sea cages of European sea bass (Dicentrarchus labrax) and gilthead sea bream (Sparus aurata) and then a typology was developed to classify the studied farms into rearing practice groups using HCPC; (ii) LCA was performed on each aquaculture farm and (iii) mean impacts and contributions of production phases were calculated for each group of farms. Impact categories included acidification, eutrophication, global warming, land occupation, total cumulative energy demand and net primary production use.Results and discussion
Results revealed high correlation between rearing practices and impacts. The feed-conversion ratio (FCR), water column depth under the cages and cage size had the greatest influence on impact intensity. Rearing practices and fish feed were the greatest contributors to the impacts studied due to the production of fish meal and oil and the low efficiency of feed use, which generated large amounts of nitrogen and phosphorus emissions. It is necessary to optimise the diet formulation and to follow better feeding strategies to lower the FCR and improve farm performance. Water column depth greatly influenced the farms’ environmental performance due to the increase in waste dispersion at deeper depths, while shallow depths resulted in accumulation of organic matter and degradation of water quality. Cage size influences environmental performances of aquaculture farms. Thus, from an environmental viewpoint, decision makers should grant licences for farms in deeper water with larger cages and encourage them to improve their FCRs.Conclusions
This study is the first attempt to combine the HCPC method and the LCA framework to study the environmental performance of aquacultural activity. The typology developed captures the variability among farms because it considers several farm characteristics in the classification. The LCA demonstrated that technical parameters in need of improvement are related to the technical expertise of farm managers and workers and to the location of the farm.176.
177.
Khaled A. El-Tarabily Giles E. St. J. Hardy Krishnapillai Sivasithamparam Ipek D. Kurtböke 《Plant and Soil》1996,183(2):279-290
Application of lime (4000 kg ha-1) to a soil used for commercial carrot production (pH 6.9) significantly (p<0.05) reduced the incidence of cavity spot disease of carrots compared to unlimed soil (pH 5.1). It significantly (p<0.01) increased soil microbial activity as measured by the hydrolysis of fluorescein diacetate and arginine ammonification. The application of lime resulted in a significant (p<0.01) increase in the total numbers of colony forming units (efu) of aerobic bacteria, fluorescent pseudomonads, Gram negative bacteria, actinomycetes and a significant (p<0.01) decrease in the cfu of filamentous fungi and yeasts compared to unlimed soil. Liming also increased the cfu of non-streptomycete actinomycetes rarely reported in similar studies. These non-streptomycete actinomycetes were estimated and isolated using polyvalent Streptomyces phages and the dry heat technique to reduce the dominance of streptomycetes on isolation plates. The non-streptomycete actinomycetes isolated included species of Actinoplanes, Micromonospora, Streptoverticillium, Nocardia, Rhodococcus, Microbispora, Actinomadura, Dactylosporangium and Streptosporangium. The numbers of actinomycetes antagonistic to Pythium coloratum, a causal agent of cavity spot disease of carrots increased in soil amended with lime. Application of lime also reduced the isolation frequency of P. coloratum from asymptomatic carrot roots grown in soil artificially infested with the pathogen, 3, 4 and 5 weeks after sowing. 相似文献
178.
The nucleotide sequence data reported in this Papershave been submitted to the GenBank nucleotide sequence database and have been assigned the accession numbers L36065 and L36068 相似文献
179.
Axenic transformed shoot cultures of Pimpinella anisum (anise) were established following inoculation of plant stems with the nopaline strain T37 of Agrobacterium tumefaciens. The stable incorporation of T-DNA in the transformed tissues was demonstrated by polymerase chain reaction. Total essential oil accumulated by transformed shoot cultures grown under continuous light was found to be 18% lower (per unit fresh weight of tissue) than that produced by untransformed shoot cultures incubated under similar conditions, but more than 89% lower than the yield of oil from the intact plant. The relative amounts of the principal components of the essential oil of the transformed shoot cultures, namely geraniol, -bisabolene, trans-pseudoisoeugenol-2-methylbutyrate and transanethole, were similar to those present in the parent plant, but significantly different from those of the untransformed shoot cultures.Abbreviations T-DNA
transfer-DNA
- MS
Murashige and Skoog medium
- 2,4-D
2,4-dichlorophenoxyacetic acid
- TY
tryptone and yeast extract medium
- tD
doubling time
- GC-MS
gas chromatography coupled with mass spectrometry
- FID
flame ionisation detector
- PCR
polymerase chain reaction
- TE
Tris-HCl, EDTA buffer
- TBE
Tris, borate, EDTA buffer 相似文献
180.
Khaled R. A. Abdellatif Phoebe F. Lamie Hany A. Omar 《Journal of enzyme inhibition and medicinal chemistry》2016,31(2):318-324
In a new group of 3-methyl-2-phenyl-1-substituted-indole derivatives (10a–f), the indomethacin analogs were prepared via the Fisher indole synthesis reaction of propiophenone with appropriately substituted phenylhydrazine hydrochloride. This is followed by the insertion of the appropriate benzyl or benzoyl fragment. All the synthesized compounds were evaluated for their anti-inflammatory (in vitro and in vivo) and analgesic activities. The methanesulphonyl derivatives 10d, e and f showed the highest anti-inflammatory (in vitro and in vivo) and analgesic activities. In addition, molecular docking studies were performed on compounds 10a–f and the results were in agreement with that obtained from the in vitro COX inhibition assays. The significant anti-inflammatory and analgesic activities exhibited by 10d and 10e warrant continued preclinical development as potential anti-inflammatory and analgesic agents. 相似文献