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131.
Nehal?Hussein Abdel-Rahman?N?ZekriEmail author Mohamed?AbouelhodaEmail author Hanaa?M?Alam El-din Ahmed?Abdelwahab?Ghamry Mahmoud?A?Amer Ghada?M?sherif Abeer?A?Bahnassy 《Virology journal》2014,11(1):231
Introduction
Hepatitis C virus (HCV) genome contains two envelope proteins (E1 and E2) responsible for the virus entry into the cell. There is a substantial lack of sequences covering the full length of E1/E2 region for genotype 4. Our study aims at providing new sequences as well as characterizing the genetic divergence of the E1/E2 region of HCV 4a using our new sequences along with all publicly available datasets.Methods
The genomic segments covering the whole E1/E2 region were isolated from Egyptian HCV patients and sequenced. The resulting 36 sequences 36 were analyzed using sequence analysis techniques to study variability within and among hosts in the same time point. Furthermore, previously published HCV E1/E2 sequence datasets for genotype 4a were retrieved and categorized according to the geographical location and date of isolation and were used for further analysis of variability among Egyptian over a period of 15 years, also compared with non-Egyptian sequences to figure out region-specific variability.Results
Phylogenetic analysis of the new sequences has shown variability within the host and among different individuals in the same time point. Analysis of the 36 sequences along with the Egyptian sequences (254 sequences in E1 in the period from 1997 to 2010 and 8 E2 sequences in the period from 2006 to 2010) has shown temporal change over time. Analysis of the new HCV sequences with the non-Egyptian sequences (182 sequences in E1 and 155 sequences in the E2) has shown region specific variability. The molecular clock rate of E1 was estimated to be 5E-3 per site per year for Egyptian and 5.38E-3 for non-Egyptian. The clock rate of E2 was estimated to be 8.48E per site per year for Egyptian and 6.3E-3 for non-Egyptian.Conclusion
The results of this study support the high rate of evolution of the Egyptian HCV genotype 4a. It has also revealed significant level of genetic variability among sequences from different regions in the world.132.
Manal Fawzy Amal M. Abdel-Rahman Gihan Hosny Balqees Raheem Odhafa 《International journal of phytoremediation》2019,21(12):1205-1214
AbstractIn this study, the techno-economic approach of olive leaves (Olea europaea L.) wastes for the removal of Cd2+ from aqueous solutions was demonstrated. The adsorption process was illustrated regarding batch experiments and scanning electron microscopy, energy dispersive X-ray, and Fourier-transform infrared characterization. The optimum pH and contact time were 6.6 and 123?min, respectively, giving Cd2+ removal efficiencies of 94.9% at Co = 50?mg/L and 81.5% at Co = 100?mg/L. The monolayer adsorption capacity of the Langmuir isotherm model was 32.6?mg/g (R2 = 0.97). The adsorption mechanisms might be related to (a) ion exchange with cations (e.g., K+, Na+, and Ca2+), (b) formation of cadmium chloride complexes, (c) interaction with oxygen-containing functional groups, (d) physical agglomeration in the pore surface, and (e) precipitation interaction using inorganic minerals (i.e., carbonates, phosphates, and silicates). The total cost of the adsorption process for the treatment of ions-containing wastewater was 0.038 $USD/m3. Assuming a benefit-cost of tertiary treated water as 0.044 $USD/m3, the adsorption system could attain a payback period of 5.7?years. This period was shorter than the lifetime of the capital investment (i.e., 10?years), and hence, the project would be economically feasible for an application. 相似文献
133.
134.
E.A. El-Shazly I.A. Ismail H.A. El Shabrawy R.S. Abdel-Rahman 《Archives Of Phytopathology And Plant Protection》2013,46(19):2304-2313
This study was conducted on Bt and normal maize hybrids during two successive sowing dates, early and late summer plantation. The Sesamia cretica larvae were observed for the first time on first week of April on different commercial maize hybrids. While there was no larva/plant on transgenic maize hybrids, YieldGard and Ageeb-YG, while larvae were found on last week of July by a very little number on maize hybrids for late one. In Early summer planting date showed highly significant differences in reduction percent, between tested compounds and control one, in the pink corn borer population. The bio-residual activity of the NeemAzal-T/S 0.5% on TWC310 was significantly less pronounced, i.e. 75.5%, than other tested ones; the highest percentage of reduction, 86.6%, was achieved by Chlorophan 0.005% on SC2031, followed by NeemAzal-T/S 0.5% on SC2031 83.5% and Chlorophan 0.005% on SC2030 83.4%, respectively. Also the average reduction percentage of S. cretica larvae differed significantly from 69.6%, on NeemAzal-T/S SC2031, to 83.0%, on Chlorophan SC2031, in the late summer planting. The different treatments had positive effects on maize yield in the two planting dates. In the first plantation date, the increased rate of control ranged from 1.04 to 1.24, when NeemAzal-T/S acted on TWC310 and transgenic IYG, respectively. And in the second plantation date, rate of control obtained was 1.06–1.30, when NeemAzal-T/S acted on SC 2031 and transgenic IYG, respectively. The tested compounds played an important role in controlling the pink corn borer insect, S. cretica, and this study suggests that Cry 1Ab-expressing corn hybrids would provide a great value as a component of corn IPM in Egypt. 相似文献
135.
When the phytochrome molecule of maize coleoptiles absorbs sufficientenergy it binds to its putative binding site in a particulatefraction irrespective of whether or not it is in the Pfr form.The extent of binding depends on the light dosage. Red lightis more efficient than far red light but both are effectivein causing phytochrome to bind. Using phytochrome binding tosubcellular particles as the prototype of a primary physiologicalresponse it is concluded that Pfr may not necessarily be theonly physiologically active form of phytochrome. (Received May 31, 1976; ) 相似文献
136.
We have recently shown that estrogen negatively modulates the hypotensive effect of clonidine (mixed alpha2-/I1-receptor agonist) in female rats and implicates the cardiovascular autonomic control in this interaction. The present study investigated whether this effect of estrogen involves interaction with alpha2- and/or I1-receptors. Changes evoked by a single intraperitoneal injection of rilmenidine (600 microg/kg) or alpha-methyldopa (100 mg/kg), selective I1- and alpha2-receptor agonists, respectively, in blood pressure, hemodynamic variability, and locomotor activity were assessed in radiotelemetered sham-operated and ovariectomized (Ovx) Sprague-Dawley female rats with or without 12-wk estrogen replacement. Three time domain indexes of hemodynamic variability were employed: the standard deviation of mean arterial pressure as a measure of blood pressure variability and the standard deviation of beat-to-beat intervals (SDRR) and the root mean square of successive differences in R-wave-to-R-wave intervals as measures of heart rate variability. In sham-operated rats, rilmenidine or alpha-methyldopa elicited similar hypotension that lasted at least 5 h and was associated with reductions in standard deviation of mean arterial pressure. SDRR was reduced only by alpha-methyldopa. Ovx significantly enhanced the hypotensive response to alpha-methyldopa, in contrast to no effect on rilmenidine hypotension. The enhanced alpha-methyldopa hypotension in Ovx rats was paralleled with further reduction in SDRR and a reduced locomotor activity. Estrogen replacement (17beta-estradiol subcutaneous pellet, 14.2 microg/day, 12 wk) of Ovx rats restored the hemodynamic and locomotor effects of alpha-methyldopa to sham-operated levels. These findings suggest that estrogen downregulates alpha2- but not I1-receptor-mediated hypotension and highlight a role for the cardiac autonomic control in alpha-methyldopa-estrogen interaction. 相似文献
137.
M S Abdel-Rahman A S Reddi F A Curro R M Turkall A M Kadry J A Hansrote 《Canadian journal of physiology and pharmacology》1991,69(10):1436-1442
BC powder (I) is a commercially available analgesic containing the active ingredients aspirin and salicylamide. The kinetics of I, BC powder minus aspirin (II), and BC powder minus salicylamide (III) were evaluated in 13 volunteers. Ten minutes after administration of I, aspirin reached a maximum concentration of 12.9 micrograms/mL, while salicylamide concentration reached a peak value of 3.4 micrograms/mL. However, when III was administered, aspirin was not detected at 10 min and only reached a concentration of 0.4 microgram/mL at 2 and 6 h. Furthermore, the area under the plasma concentration versus time curve for aspirin when III was administered was sixfold less compared with treatment with I. The area under the curve for aspirin metabolites was significantly different in I versus III. After treatment with II, a delay in salicylamide peak concentration was observed. Gentisamide was not detected throughout the study. This study demonstrates that salicylamide significantly enhances plasma levels of aspirin with potential therapeutic implications. 相似文献
138.
Radwa A. Hanafy Britny Johnson Noha H. Youssef Mostafa S. Elshahed 《Environmental microbiology》2020,22(9):3883-3908
The anaerobic gut fungi (AGF, Neocallimastigomycota) reside in the alimentary tracts of herbivores where they play a central role in the breakdown of plant material. Here, we report on the development of the hypervariable domains D1/D2 of the large ribosomal subunit (D1/D2 LSU) as a barcoding marker for the AGF. We generated a reference D1/D2 LSU database for all cultured AGF genera, as well as the majority of candidate genera encountered in prior internal transcribed spacer 1 (ITS1)-based surveys. Subsequently, a D1/D2 LSU-based diversity survey using long read PacBio SMRT sequencing was conducted on faecal samples from 21 wild and domesticated herbivores. Twenty-eight genera and candidate genera were identified, including multiple novel lineages that were predominantly, but not exclusively, identified in wild herbivores. Association between certain AGF genera and animal lifestyles, or animal host family was observed. Finally, to address the current paucity of AGF isolates, concurrent isolation efforts utilizing multiple approaches to maximize recovery yielded 216 isolates belonging to 12 different genera, several of which have no prior cultured-representatives. Our results establish the utility of D1/D2 LSU and PacBio sequencing for AGF diversity surveys, the culturability of multiple AGF taxa, and demonstrate that wild herbivores represent a yet-untapped reservoir of AGF diversity. 相似文献
139.
Hyperlipidemia is one of the major risk factors for atherosclerosis and ischemic heart disease. Chromium (Cr) mineral is playing a crucial role in glucose and lipid homeostasis. The aim of this study was to evaluate the protective effects of combined chromium picolinate (CrPic) and atorvastatin treatment against hyperlipidemia-induced cardiac injury. Seventy-five male albino rats were divided into five groups (15 rats each). Hyperlipidemia was induced by intraperitoneal injection of a single dose of Triton X-100 (300 mg/kg body weight (b.w) (group ??). Treatment of hyperlipidemic rats was induced by daily administration of CrPic at a dose of 200 μg/kg b.w/day (group ???), atorvastatin at a dose of 10?mg/kg/day (group IV), and combined treatment with both (group V) by gavage for 7 days. At the end of experiment, serum and heart tissues were obtained. Hyperlipidemia was confirmed by histopathology of heart tissues, marked serum dyslipidemia, increased atherogenic indices, and values of ischemia-modified albumin. In addition to increased values of proprotein convertase subtilisin/kexin type 9, activity of 3-hydroxy-3-methylglutaryl coenzyme A reductase enzyme and high relative expression levels of pentraxin-3 were observed. However, paraoxonase-1 activity was markedly decreased in the hyperlipidemic group. Significant improvement in all assessed parameters was observed in the rat group treated with both CrPic and atorvastatin. It can be concluded that combined CrPic and atorvastatin treatments had synergistic cardioprotective effects against hyperlipidemia which may be through modulating atherosclerosis as well as cardiac and aortic damage and/or activation of anti-inflammatory and anti-oxidant pathways, thus reversing endothelial dysfunction. 相似文献
140.
This study dealt with the long-term effects of hypertension on circadian rhythms of hemodynamic and cardiovascular autonomic functions in radiotelemetered rats. Blood pressure (BP), heart rate (HR), spontaneous locomotor activity, and respiration.were monitored in spontaneously hypertensive rats (SHRs), a model of human hypertension, from 14 to 27 weeks of age and in Wistar-Kyoto rats (WKY) as controls. Cardiovascular autonomic changes were determined by time-domain analysis of the variability of BP (standard deviation of mean arterial pressure, SDMAP) and HR (standard deviation of R-R intervals, SDRR, and the root mean square of successive differences in R-R intervals, rMSSD). Compared with WKY rats, the 24-hr MAP and SDMAP were higher at week 14 in SHRs and showed stepwise increases over the study duration, suggesting progressive increases in vasomotor sympathetic activity in hypertensive rats. Also, higher SDRR, rMSSD, and activity and lower HR and respiration were demonstrated in SHRs. Normal circadian rhythms (higher dark-time values) of MAP, HR, SDMAP, and SDRR were evident in WKY rats at week 20 and continued thereafter. Compared with WKY rats, the circadian BP and HR patterns were abolished and inverted, respectively, in SHRs. Lower dark-time, compared with light-time, SDMAP values were observed in SHRs that were associated with temporal increases in HR variability indices. These findings demonstrate that hypertension elicits significant alterations in circadian autonomic and hemodynamic profiles. Further, the steady increases in BP, average level and oscillations, in SHRs may explain the reported progressive age-related vascular and cardiac hypertrophy in these rats. 相似文献