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51.
Bassam M. Ayoub Yasmeen M. Attia 《Journal of enzyme inhibition and medicinal chemistry》2018,33(1):858-866
Chemical entities with structural diversity were introduced as candidates targeting adenosine receptor with different clinical activities, containing 3,7-dihydro-1H-purine-2,6-dione, especially adenosine 3 receptors (ADORA3). Our initial approach started with pharmacophore screening of ADORA3 modulators; to choose linagliptin (LIN), approved anti-diabetic drug as Dipeptidyl peptidase-4 inhibitors, to be studied for its modulating effect towards ADORA3. This was followed by generation, purification, analytical method development, and structural elucidation of oxidative degraded product (DEG). Both of LIN and DEG showed inhibitory profile against hepatocellular carcinoma cell lines with induction of apoptosis at G2/M phase with increase in caspase-3 levels, accompanied by a downregulation in gene and protein expression levels of ADORA3 with a subsequent increase in cAMP. Quantitative in vitro assessment of LIN binding affinity against ADORA3 was also performed to exhibit inhibitory profile at Ki of 37.7?nM. In silico molecular modelling showing binding affinity of LIN and DEG towards ADORA3 was conducted. 相似文献
52.
53.
CTS Silva V. Wanderley-Teixeira FM Cunha JV Oliveira KA Dutra DMA Ferraz Navarro 《Biotechnic & histochemistry》2018,93(1):36-48
The armyworm, Spodoptera frugiperda, is the principal pest of corn in Brazil. Control is achieved primarily by synthetic insecticides, which cause problems for the agro-ecosystem. Alternative methods of control are under investigation and citronella (Cymbopogon winterianus) essential oil appears to be a promising agent. We investigated the effects of citronella oil using histological, histochemical and immunohistochemical methods. The midgut of larvae treated with citronella exhibited altered epithelium including cytoplasmic protrusions, columnar cell extrusion, pyknotic nuclei, and increased periodic acid-Schiff positive granules. Regenerative cells in the epithelium of the midgut increased in number, which facilitated subsequent regeneration of this tissue. After exposure to citronella, trophocytes, the principal cell type of the fat body, possessed enlarged vacuoles and mitotic bodies, and contained reduced amounts of glycogen, lipid, and protein. Citronella oil caused morphological changes of the midgut and reduction of stored resources in the fat body, which may adversely affect insect reproduction and survival. 相似文献
54.
ABSTRACTSleep deprivation impairs performance on cognitive tasks, but it is unclear which cognitive processes it degrades. We administered a semantic matching task with variable stimulus onset asynchrony (SOA) and both speeded and self-paced trial blocks. The task was administered at the baseline and 24 hours later after 30.8 hours of total sleep deprivation (TSD) or matching well-rested control. After sleep deprivation, the 20% slowest response times (RTs) were significantly increased. However, the semantic encoding time component of the RTs remained at baseline level. Thus, the performance impairment induced by sleep deprivation on this task occurred in cognitive processes downstream of semantic encoding. 相似文献
55.
Meriem Tekaya Sinda El-Gharbi Beligh Mechri Hechmi Chehab Amani Bchir Imed Chraief Mouna Ayachi Dalenda Boujnah Faouzi Attia Mohamed Hammami 《Acta Physiologiae Plantarum》2016,38(4):101
Most of the studies investigated the effects of nutrient-based fertilizers on olive fruits and oil quality; few studies have been interested in the modification of the chemical composition of olive leaves in response to fertilization. Thus, the current study aims to examine the effects of foliar fertilization on the mineral profile of olive leaves as well as the concentrations of chlorophyll, antioxidants (phenolic compounds) and carbohydrates. Experimentation consists of the annual application of six treatments during two successive growing seasons (2009–2010): TC (untreated trees), P1 (nitrogen-based fertilizer), P2 (contains boron, magnesium and manganese), P3 (phosphorus and potassium based fertilizer), P4 (rich in calcium and phosphorus), T5 (P1 and P2 application) and T6 (P1, P2, P3 and P4 application). At the end of the experiment, mineral analysis of olive leaves showed an increase in the concentrations of most nutrients which induced changes in biochemical composition: an increase of chlorophyll content, a reduction of total phenols and oleuropein concentrations coupled with an increase of hydroxytyrosol level. Moreover, an increase of total sugar content and most individual sugars, principally translocated forms of sugars (mannitol, sucrose and raffinose), was also observed. The accumulation of these key physiological parameters by foliar fertilization suggests an improvement of physiological performance and photosynthetic capacity of olive trees. Moreover, from a biological point of view, the results of the study revealed the possibility to improve plants of medicinal interest by enhancing the accumulation of some bio-active compounds, such as hydroxytyrosol and mannitol, via foliar nutrient supply. 相似文献
56.
Trade in freshwater ornamental fish in South Africa is currently regulated by a ‘blacklist’ to prevent potentially invasive taxa from establishing in the country. Because its effective implementation requires accurate identification, the aim of the present study was to test whether DNA barcoding is a useful tool to identify freshwater fishes in the South African pet trade. A total of 351 aquarium fish specimens, representing 185 traded taxa, were sequenced for the mitochondrial COI barcoding marker in 2011 and 2012. Lake Malawi cichlids were treated as a single group due to a lack of resolution in their COI marker, resulting in a data set of 137 successfully sequenced taxa. The Barcode Of Life Database (BOLD) and GenBank were used for taxonomic assignment comparisons. The genetic identification matched the scientific name inferred from the trade name for 60 taxa (43.8%) using BOLD, and for 67 taxa (48.9%) using GenBank. A genetic ID could not be assigned in 47 (34.3%) cases using BOLD and in 37 cases (27%) using GenBank. Whereas DNA barcoding can be a useful tool to help identify imported freshwater fishes, it requires further development of publicly available databases to become a reliable means of identification. 相似文献
57.
Houneida Attia Najoua Karray Ahlem Ellili Najoua Msilini Mokhtar Lachaâl 《Acta Physiologiae Plantarum》2009,31(5):1045-1051
In order to diversify the production of plants with pharmacological interest, it is important to understand the mechanisms
involved in their tolerance to environmental constraints, such as salinity. Basil (Ocimum basilicum), known for its therapeutic uses, has been claimed to be salt tolerant, but physiological aspects of this behavior remain
unknown. Since salt tolerance is known to be associated with several characteristics concerning Na+ transport to leaves, we studied this function in hydroponically grown basil. We analyzed the response of 30-day-old seedlings
to 25–50 mM NaCl applied for 15 days. Growth was poorly affected, indicating that these concentrations corresponded to the
tolerated salinity range. Leaves accumulated Na+ at relatively high concentration, without dehydrating. Potassium concentration in leaf tissues was maintained close to control
level, indicating that K+ was 15- to 25-fold preferred over Na+ for ion transport and deposition. Collection of xylem sap on detopped plants revealed that this preference was only 10-fold
for ion introduction into root xylem sap. Short-term (24 h) changes in Na+ distribution between organs after stem (steam) girdling suggested that Na+ downward recirculation by phloem occurred. Although modest, this transport might have augmented K+ selectivity of ion deposition in leaves. 相似文献
58.
Najoua Msilini Houneida Attia Najoua Bouraoui Sabah M’rah Riadh Ksouri Mokhtar Lachaal Zeineb Ouerghi 《Acta Physiologiae Plantarum》2009,31(4):849-853
Morpho-physiological and biochemical responses of Arabidopsis thaliana (accession N1438) to bicarbonate-induced iron deficiency were investigated. Plants were grown in cabinet under controlled
conditions, in a nutrient solution containing 5 μM Fe, added or not with 10 mM NaHCO3. After 30 days, bicarbonate-treated plants displayed significantly lower biomass, leaf number and leaf surface area as compared
to control plants, and slight yellowing of their younger leaves was observed. Potassium (K+) content was not modified by bicarbonate treatment in roots, whereas it was significantly diminished in shoots. Their content
in ferrous iron (Fe2+) and in leaf total chlorophylls was noticeably lower than in control plants. Root Fe(III)-chelate reductase and phosphoenolpyruvate
carboxylase (PEPC) activities were significantly enhanced, but leaf ribulose 1.5-bisphosphate carboxylase (Rubisco) activity
was decreased. 相似文献
59.
Imran Sajid Clarisse Blandine Fotso Fondja Yao Khaled Attia Shaaban Shahida Hasnain Hartmut Laatsch 《World journal of microbiology & biotechnology》2009,25(4):601-610
A culture collection of 110 indigenous Streptomyces strains originally isolated from saline farmlands (Punjab, Pakistan) using stringent methods was screened biologically and
chemically to investigate their potential for the production of bioactive secondary metabolites. In a biological screening
the crude extracts obtained from the culture broth of selected strains were analysed for their activity against a set of test
organisms, including Gram-positive, Gram-negative bacteria, fungi and microalgae using the disk diffusion bioassay method.
Additionally a cytotoxicity test was performed by means of the brine shrimp microwell cytotoxicity assay. In a chemical screening
each of the crude extracts was analysed by TLC using various staining reagents and by HPLC-MS/MS measurements. The results
depicted an impressive chemical diversity of crude extracts produced by these strains. The taxonomic status of the selected
strains was confirmed by preliminary physiological testing and 16S rRNA gene sequencing. 相似文献
60.