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71.
M. Lteif R. Mouawad G. Khalaf P. Lenfant B. Seret M. Verdoit‐Jarraya 《Journal of fish biology》2017,91(5):1491-1509
A total of 38 individuals of the heavily exploited little gulper shark Centrophorus uyato were collected from Lebanese coastal waters using bottom longlines and trammel nets of different meshes at depths ranging from 115 to 600 m between May 2013 and February 2014. Their total lengths were between 45 and 94 cm and their total mass was from 870 to 6700 g. The sex ratio was not significantly different from 1:1, with 20 males and 18 females, but bathymetric sexual segregation occurred. Catch per net setting (CNS) was used as a relative abundance index to detect spatial distribution; trammel nets showed largest CNS ranging from 4·9 to 5·45 kg per unit effort in the north and south, at depths from 120 to 200 m, during spring and summer. The mass–length relationships demonstrated negative allometric growth (b < 3) (males: MT = 0.3585LT2·071, r2 = 0·94; females: MT = 0.0239LT2·735, r2 = 0·64). The condition factor as well as the gonado‐somatic and hepato‐somatic indices of C. uyato in the study area were also calculated. The results are discussed in relation to the distribution, growth and reproduction as well as the management of C. uyato. 相似文献
72.
The program GRID was used to design novel potential inhibitors of human sorbitol dehydrogenase based on a model of the holoenzyme in complex with the inhibitor WAY135 706. Replacement of the methyl hydroxyl group of the inhibitor with methyl phosphate and methyl carboxylate functional groups increased the net binding energy of the complex by 2.0- and 1.7-fold, respectively. This study may be useful in the development of potent and more specific inhibitors of the enzyme. 相似文献
73.
Eetmad A. Arafat Eman M.I. Youssef Hanaa A. Khalaf 《European journal of histochemistry : EJH》2021,65(4)
The purpose of this work was to prove that oxidative stress is the main mechanism responsible for retinal neurodegenerative changes, subsequent apoptosis, and inflammatory cytokine release in rats fed with a high cholesterol diet (HCD) and determine the role of garlic in alleviating these changes. Forty rats were equally divided into four groups: control, garlic-treated (positive control), HCD, and HCD + garlic-treated (HCD + G). By the end of the experiment (24 weeks) blood samples were collected for assessment of serum lipid profile, oxidative stress parameters, and plasma levels of IL-6 and TNF-α. Both eyes of the rats were enucleated; one was used for light microscopic examination and the other for electron microscopic examination. There was a significant increase in the levels of serum lipids, oxidative stress parameters, IL-6 and TNF-α, and area of expression of caspase-3 in the HCD group compared to both the control and HCD + G groups. Histological examination revealed degenerative changes in all layers of the neural retina in the HCD group. Garlic administration resulted in a significant improvement in the biochemical, immunohistochemical, and histological characteristics of hypercholesterolemic rats. These findings support the hypotheses that garlic has strong antioxidant, anti-apoptotic, and anti-inflammatory properties. Garlic ameliorates the neurodegenerative changes in the neural retina of hypercholesteremic rats.Key words: Hypercholesterolemia, garlic, neural retina 相似文献
74.
75.
Hazem Khalaf Jana Jass Per-Erik Olsson 《International Journal of Biochemistry and Molecular Biology》2013,4(3):150-156
T-cells play an important role in host immunity against invading pathogens. Determining the underlying regulatory mechanisms will provide a better understanding of T-cell-derived immune responses. In this study, we have shown the differential regulation of IL-6 and CXCL8 by NF-κB and NFAT in Jurkat T-cells, in response to PMA, heat killed Escherichia coli and calcium. CXCL8 was closely associated with the activation pattern of NFAT, while IL-6 expression was associated with NF-κB. Furthermore, increasing the intracellular Ca2+ concentration by calcium ionophore treatment of the cells resulted in NFAT induction without affecting the NF-κB activity. Interestingly, NF-κB activation by heat killed E. coli, as well as CXCL8 and IL-6 expression was significantly suppressed following addition of the calcium ionophore. This indicates that calcium plays an important role in regulating protein trafficking and T-cell signalling, and the subsequent inflammatory gene expression infers an involvement of NFAT in CXCL8 regulation.Understanding these regulatory patterns provide clarification of conditions that involve altered intracellular signalling leading to T-cell-derived cytokine expression. 相似文献
76.
Deya Eldeen Mohammed Radwan Khalaf Ali Fayez Sabry Younis Mahmoud Guoquan Lu 《Acta Physiologiae Plantarum》2010,32(5):891-904
The antioxidant status as well as protein composition of faba bean leaves infected with Bean yellow mosaic virus (BYMV) and the effect of salicylic acid application was examined in this paper. Some modifications in the antioxidant status
were observed by changing some antioxidant enzymes activities and contents of antioxidant metabolites. BYMV-infected leaves
revealed POD, CAT, APX and SOD induced activities while SA treatments could inhibit POD, CAT activities but induced SOD activity.
The enzyme activities seemed to be SA concentration dependant. Higher H2O2 and MDA concentrations were recorded in virus-infected leaves than those of the corresponding controls while treatment with
SA followed by virus inoculation caused lowering of MDA concentration and reducing the damage due to lipid peroxidation. Moreover,
because of virus infection and/or SA treatments, an increase in the amounts of phenolics and flavonoids was noticed. As compared
to the control, BYMV infection or SA application caused pronounced increase in the antioxidant activity of leaf extracts detected
by DPPH assay, indicating an increase in the amounts of antioxidant compounds occurred. To test the protein composition, the
contents of each protein fractions (soluble, insoluble and total) were analyzed and the change in protein patterns was visualized
using SDS-PAGE. The BYMV-infected bean leaves had protein contents higher than the control indicating accumulation of pathogenesis-related
proteins. Moreover, spraying SA with or without virus inoculation could accumulate soluble, insoluble and total proteins and
the pattern of increase was in accordance with SA concentration. Alterations in protein patterns were observed in faba bean
leaves (Vicia faba cv Giza 461) in response to BYMV infection and SA treatments. Because of BYMV infection and SA treatments, the protein profiles
showed new bands in comparison to the control. Some polypeptides were highly accumulated in treatments of SA followed by virus
inoculation. Changing antioxidant status and accumulation of some antioxidant metabolites as well as the pronounced alterations
in the protein composition indicate a kind of plant response against pathogen invasion and in case of SA treatment it is considered
a way by which a defence response was initiated and/or activated. 相似文献
77.
Muttalip Gundogdu Koray Ozrenk Sezai Ercisli Tuncay Kan Ossama Kodad Attila Hegedus 《Biological research》2014,47(1)
Background
The Hawthorn (Crateagus sp.) mostly occurs around the temperate region of the world with a high number of species, producing a fruit with numerous beneficial effects for human health. The aim of the study was to determine organic acid and sugar contents in the fruit of a number of hawthorn species grown in Erzincan province of Turkey.Results
Citric acid was the predominant organic acid in all hawthorn species and C. pseudoheterophylla had the highest citric acid content (23.688 g/100 g). There were not statistically significant differences among hawthorn species (except C. atrosanguinea Pojark) in terms of fumaric acid content. C.pontica C.Koch had a higher content of vitamin C (9.418 mg/100 g) compared to other species. Fructose was the predominant sugar component in all species and C. monogyna subsp. monogyna Joiq had the highest fructose content (18.378 g/100 g).Conclusions
The high fruit quality of the studied species indicates the importance of this fruit in human nutrition as a natural source. The study revealed that there were differences in terms of fruit characteristics among hawthorn species and thus better quality hawthorn genotypes can be selected within the species. Hence, this study is considered to be a valuable reference for forthcoming studies. The high fruit quality of the studied species indicates the importance of this fruit in human nutrition as a natural source. 相似文献78.
79.
Yosra Shaaban R. Elnaggar Magda A. El-Massik Ossama Y. Abdallah Abd Elazim R. Ebian 《AAPS PharmSciTech》2010,11(2):645-651
The recent challenge in orally disintegrating tablets (ODT) manufacturing encompasses the compromise between instantaneous
disintegration, sufficient hardness, and standard processing equipment. The current investigation constitutes one attempt
to fulfill this challenge. Maltodextrin, in the present work, was utilized as a novel excipient to prepare ODT of meclizine.
Tablets were prepared by both direct compression and wet granulation techniques. The effect of maltodextrin concentrations
on ODT characteristics—manifested as hardness and disintegration time—was studied. The effect of conditioning (40°C and 75%
relative humidity) as a post-compression treatment on ODT characteristics was also assessed. Furthermore, maltodextrin-pronounced
hardening effect was investigated using differential scanning calorimetry (DSC) and X-ray analysis. Results revealed that
in both techniques, rapid disintegration (30–40 s) would be achieved on the cost of tablet hardness (about 1 kg). Post-compression
conditioning of tablets resulted in an increase in hardness (3 kg), while keeping rapid disintegration (30–40 s) according
to guidance of the FDA for ODT. However, direct compression-conditioning technique exhibited drawbacks of long conditioning
time and appearance of the so-called patch effect. These problems were, yet, absent in wet granulation-conditioning technique.
DSC and X-ray analysis suggested involvement of glass-elastic deformation in maltodextrin hardening effect. High-performance
liquid chromatography analysis of meclizine ODT suggested no degradation of the drug by the applied conditions of temperature
and humidity. Overall results proposed that maltodextrin is a promising saccharide for production of ODT with accepted hardness-disintegration
time compromise, utilizing standard processing equipment and phenomena of phase transition. 相似文献
80.
Kinlough CL McMahan RJ Poland PA Bruns JB Harkleroad KL Stremple RJ Kashlan OB Weixel KM Weisz OA Hughey RP 《The Journal of biological chemistry》2006,281(17):12112-12122
MUC1 is a mucin-like transmembrane protein expressed on the apical surface of epithelia, where it protects the cell surface. The cytoplasmic domain has numerous sites for phosphorylation and docking of proteins involved in signal transduction. In a previous study, we showed that the cytoplasmic YXXphi motif Y20HPM and the tyrosine-phosphorylated Y60TNP motif are required for MUC1 clathrin-mediated endocytosis through binding AP-2 and Grb2, respectively (Kinlough, C. L., Poland, P. A., Bruns, J. B., Harkleroad, K. L., and Hughey, R. P. (2004) J. Biol. Chem. 279, 53071-53077). Palmitoylation of transmembrane proteins can affect their membrane trafficking, and the MUC1 sequence CQC3RRK at the boundary of the transmembrane and cytoplasmic domains mimics reported site(s) of S-palmitoylation. [3H]Palmitate labeling of Chinese hamster ovary cells expressing MUC1 with mutations in CQC3RRK revealed that MUC1 is dually palmitoylated at the CQC motif independent of RRK. Lack of palmitoylation did not affect the cold detergent solubility profile of a chimera (Tac ectodomain and MUC1 transmembrane and cytoplasmic domains), the rate of chimera delivery to the cell surface, or its half-life. Calculation of rate constants for membrane trafficking of wild-type and mutant Tac-MUC1 indicated that the lack of palmitoylation blocked recycling, but not endocytosis, and caused the chimera to accumulate in a EGFP-Rab11-positive endosomal compartment. Mutations CQC/AQA and Y20N inhibited Tac-MUC1 co-immunoprecipitation with AP-1, although mutant Y20N had reduced rates of both endocytosis and recycling, but a normal subcellular distribution. The double mutant chimera AQA+Y20N had reduced endocytosis and recycling rates and accumulated in EGFP-Rab11-positive endosomes, indicating that palmitoylation is the dominant feature modulating MUC1 recycling from endosomes back to the plasma membrane. 相似文献