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151.
152.
Nasereddine Hamadi Ahmed Mansour Memy H. Hassan Fatima Khalifi‐Touhami Osama Badary 《Journal of biochemical and molecular toxicology》2012,26(10):384-392
The objective of this study was to investigate the ameliorative property and potential mechanism of resveratrol (RVT) in a dose of 10 mg/kg for 15 consecutive days against liver injury in streptozotocin‐induced diabetic rats. Diabetic rats significantly (P < 0.05) exhibited liver injury manifested by increased aspartylaminotransferase, alanine aminotransferase, and bilirubin; disturbed liver weight to body weight; and confirmed by hematoxylin and eosin staining. Liver from diabetic rats exhibited significant increase in malondialdehyde level and significant decrease in reduced glutathione, glutathione‐S‐transferase, quinone reductase, catalase, and superoxide dismutase. Diabetic rats showed significant disturbance in serum lipid profile. Treatment with RVT significantly (P < 0.05) abrogated diabetes‐induced perturbation in these parameters and liver histology. These data suggest that RVT treatment is associated with promising hepatoprotective effect against diabetes‐induced liver damage via reduction of serum glucose level and oxidative damage and improving serum lipid profile. © 2012 Wiley Periodicals, Inc. J Biochem Mol Toxicol 26:384–392, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/jbt.21432 相似文献
153.
Mansour Ebrahimi Parisa Aghagolzadeh Narges Shamabadi Ahmad Tahmasebi Mohammed Alsharifi David L. Adelson Farhid Hemmatzadeh Esmaeil Ebrahimie 《PloS one》2014,9(5)
The evolution of the influenza A virus to increase its host range is a major concern worldwide. Molecular mechanisms of increasing host range are largely unknown. Influenza surface proteins play determining roles in reorganization of host-sialic acid receptors and host range. In an attempt to uncover the physic-chemical attributes which govern HA subtyping, we performed a large scale functional analysis of over 7000 sequences of 16 different HA subtypes. Large number (896) of physic-chemical protein characteristics were calculated for each HA sequence. Then, 10 different attribute weighting algorithms were used to find the key characteristics distinguishing HA subtypes. Furthermore, to discover machine leaning models which can predict HA subtypes, various Decision Tree, Support Vector Machine, Naïve Bayes, and Neural Network models were trained on calculated protein characteristics dataset as well as 10 trimmed datasets generated by attribute weighting algorithms. The prediction accuracies of the machine learning methods were evaluated by 10-fold cross validation. The results highlighted the frequency of Gln (selected by 80% of attribute weighting algorithms), percentage/frequency of Tyr, percentage of Cys, and frequencies of Try and Glu (selected by 70% of attribute weighting algorithms) as the key features that are associated with HA subtyping. Random Forest tree induction algorithm and RBF kernel function of SVM (scaled by grid search) showed high accuracy of 98% in clustering and predicting HA subtypes based on protein attributes. Decision tree models were successful in monitoring the short mutation/reassortment paths by which influenza virus can gain the key protein structure of another HA subtype and increase its host range in a short period of time with less energy consumption. Extracting and mining a large number of amino acid attributes of HA subtypes of influenza A virus through supervised algorithms represent a new avenue for understanding and predicting possible future structure of influenza pandemics. 相似文献
154.
Cees S. Roselaar Ronald Sluys Mansour Aliabadian Peter G. M. Mekenkamp 《Journal of Ornithology》2007,148(3):271-280
A database was created of digitized equal area distribution maps of 3,036 phylogenetic species of Palearctic songbirds. Biogeographic
patterns are reported for two data sets: (1) including all passeriform bird species reported as breeding within the boundaries
of our study map, (2) passeriform species restricted in their distribution to our study region, thus excluding the partly
extra-limital taxa. With respect to the data set excluding partly extra-limital taxa, the average range size is 238 grid cells
(grid cell area: 4,062 km2). Analysis of the geographic distribution of species richness for the full data set showed several hotspot regions, mostly
located in mountainous areas. The index of range-size rarity identified similar hotspot regions as that for species richness,
albeit that the range-size rarity de-emphasized the central Siberian hotspot. Range-size rarity hotspots that are not evident
on the measure of species richness concern a great number of islands. Much more prominent on the index of range-size rarity
are the Atlas Mountains of northern Africa, the Jabal al Akhdar region in NE Libya, and the eastern border of the Mediterranean.
Restricting the analysis of geographic variation to the 25% of the species with smallest ranges resulted in a greatly simplified
pattern of hotspots.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
155.
156.
W.L. Abdou E.A. Abdel-Hakim N.Y. Salem M.H Mansour E.M. Amr 《Archives Of Phytopathology And Plant Protection》2013,46(15):1764-1772
This work was based on field screening procedure to detect the population density of Aphis craccivora for two successive seasons (2004–2005) and (2005–2006) to emphasis the relation between the economic injury level (EIL) and yield loss. Results obtained showed that the equilibrium position (steady point) during the first and second season was 9.06 and 3.32 individuals/five leaflets, respectively, while the injury level was 3.4 and 1.16 individuals/leaflets. When the bean plant was subjected to three successive insecticidal applications during the early growing, season is sufficient to decrease the yield loss significantly (yield capacity 21.43 Ard./fed.) with comparing to untreated plant (14.98 Ard./fed.), while the plants exposure for one treatment was 17.36 Ard./fed. The EIL was 8.6 individual of aphids/plant depending on the market price of bean and control cost during the season. 相似文献
157.
T.E. Mansour P.G. Morris J. Feeney G.C.K. Roberts 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》1982,721(4):336-340
31P-NMR techniques offer a useful method of studying changes in the metabolism of intact parasitic worms. The liver flukes, Fasciola hepatica, provide good quality 31P high resolution NMR spectra for at least 6 h under anaerobic conditions. The levels of ATP remain constant throughout this period. There is no signal for phosphocreatine or phosphoarginine. In contrast to the findings in mammalian tissues, there is a distinct peak for the terminal phosphate of ADP. A number of signals are observed in the phosphodiester region of the spectrum the largest of which is identified as l-α-glycerophosphoryl choline. Serotonin (5-hydroxytryptamine) causes an appreciable increase in the levels of sugar phosphates when the flukes are incubated in the absence of glucose. The addition of glucose also causes a marked increase in the signals for the hexose phosphate. 相似文献
158.
K. Kamel M. Umar W. Ibrahim A. Mansour F. Gaballah O. Selim A. Azim S. Hamza F. Sabry N. Moafy A. El-Naggar K. Hoerman 《American journal of physical anthropology》1975,43(1):103-111
Anthropological studies were done on 1276 Libyans from the Mediterranean cities of Tripoli and Benghazi, and from Sabha southward in The Sahara. The incidences of hemoglobin (Hb)-S and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency were low in the coastal areas and significantly high in Sabha. Hb-C occurred sporadically in Tripoli and Sabha, and was absent from Benghazi in the east. One case of Hb-J Benghazi was noted. There were no significant differences in the ABO blood group and Rh0 (D) type distributions in the three localities. G-6-PD gene GdA frequency was significantly high in Sabha. The lowest value of 6-phosphogluconate dehydrogenase (6-PGD) gene PGDA frequency and highest value of the gene PGDC were in Sabha. Adenylate kinase (AK) gene AK2 was only detectable in Tripoli. Acid phosphatase (AP) gene Pa frequency in Sabha was more than twice that in Tripoli and Benghazi, while Pc was distinctly lower in Sabha than in the northern cities. Haptoglobin gene Hp1 frequency was almost identical in all areas. Anthropometric measurements revealed overall homogeneity of the three samples, closer similarity in the coastal region to adjacent North African populations, and Negroid influence in the Saharan Libyans. Anthropometry substantiated findings from blood markers. 相似文献
159.
Mohammad Khabbaz Shirazi Asaad Azarnezhad Mohammad Foad Abazari Mansour Poorebrahim Pegah Ghoraeian Nima Sanadgol Hanieh Bokharaie Sahar Heydari Amin Abbasi Sahra Kabiri Maryam Nouri Aleagha Seyed Ehsan Enderami Amir Savar Dashtaki Hassan Askari 《Journal of cellular physiology》2019,234(7):11411-11423
The interplay between H2S and nitric oxide (NO) is thought to contribute to renal functions. The current study was designed to assess the role of NO in mediating the renoprotective effects of hydrogen sulfide in the 5/6 nephrectomy (5/6 Nx) animal model. Forty rats were randomly assigned to 5 experimental groups: (a) Sham; (b) 5/6 Nx; (c) 5/6Nx+sodium hydrosulfide-a donor of H 2S, (5/6Nx+sodium hydrosulfide [NaHS]); (d) 5/6Nx+NaHS+ L -NAME (a nonspecific nitric oxide synthase [NOS] inhibitor); (e) 5/6Nx+NaHS+aminoguanidine (a selective inhibitor of inducible NOS [iNOS]). Twelve weeks after 5/6 Nx, we assessed the expressions of iNOS and endothelial NOS (eNOS), oxidative/antioxidant status, renal fibrosis, urine N-acetyl-b-glucosaminidase (NAG) activity as the markers of kidney injury and various markers of apoptosis, inflammation, remodeling, and autophagy. NaHS treatment protected the animals against chronic kidney injury as depicted by improved oxidative/antioxidant status, reduced apoptosis, and autophagy and attenuated messenger RNA (mRNA) expression of genes associated with inflammation, remodeling, and NAG activity. Eight weeks Nω-nitro-l-arginine methyl ester ( L -NAME) administration reduced the protective effects of hydrogen sulfide. In contrast, aminoguanidine augmented the beneficial effects of hydrogen sulfide. Our finding revealed some fascinating interactions between NO and H 2S in the kidney. Moreover, the study suggests that NO, in an isoform-dependent manner, can exert renoprotective effects in 5/6 Nx model of CKD. 相似文献
160.
Twelve randomly-selected isolates of Fusarium graminearum that produce 3-acetyl-deoxynivalenol (3-ADON) or 15-acetyl-deoxynivalenol (15-ADON) were screened by thin-layer chromatography
(TLC) for their ability to produce ADON and zearalenone (ZEA) mycotoxins when grown on water agar containing different concentrations
of sucrose. The results showed the ability of the F. graminearum 3-ADON chemotype population to produce DON and ZEA at a lower concentration range of sucrose (5-7%) compared with the 15-ADON
chemotype (30-40%). The former distinction allows for sucrose-water agar to be employed as a rapid and simple differential
medium, where two separate sucrose-gradient concentrations discriminate 3-ADON from 15-ADON populations. In the light of the
shift in sugar concentrations occurring during the process of grain formation and maturation, the difference in mycotoxin
production between the two populations is discussed with respect to predicting Fusarium head blight (FHB) epidemiology and
accumulation of DON and ZEA. 相似文献