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31.
A series of new imidazo[5,1-b]quinazoline derivatives (VII-IX) was designed, synthesized, and biologically evaluated for their in vivo hypotensive or hypertensive activities. The design of these compounds was based upon the molecular modeling simulation of the fitting values and conformational energy values of the best-fitted conformers to both the alpha(1)-adrenoceptor (alpha(1)-AR) agonist and alpha(1)-adrenoceptor (alpha(1)-AR) antagonist hypotheses. These hypotheses were generated from their corresponding lead compounds using CATALYST software. The simulation studies predicted that compounds IXa and IXe would have probable affinity for the alpha(1)-AR antagonist hypothesis, while compounds IXb, IXc, and IXg predicted a higher affinity for the alpha(1)-AR agonist hypothesis. In vivo biological evaluation of these compounds for their effects on the blood pressure of normotensive cats was consistent with the results of molecular modeling studies, where compounds IXa and IXe exhibited hypotensive activity, while compounds IXb, IXc, and IXg resulted in increasing the blood pressure of the experimental animals at different doses. 相似文献
32.
Goodarzi H Najafabadi HS Hassani K Nejad HA Torabi N 《Journal of theoretical biology》2005,235(3):318-325
Statistical and biochemical studies have revealed non-random patterns in codon assignments. The canonical genetic code is known to be highly efficient in minimizing the effects of mistranslation errors and point mutations, since it is known that when an amino acid is converted to another due to error, the biochemical properties of the resulted amino acid are usually very similar to those of the original one. In this study, using altered forms of the fitness functions used in the prior studies, we have optimized the parameters involved in the calculation of the error minimizing property of the genetic code so that the genetic code outscores the random codes as much as possible. This work also compares two prominent matrices, the Mutation Matrix and Point Accepted Mutations 74-100 (PAM(74-100)). It has been resulted that the hypothetical properties of the coevolution theory of the genetic code are already considered in PAM(74-100), giving more evidence on the existence of bias towards the genetic code in this matrix. Furthermore, our results indicate that PAM(74-100) is biased towards the single base mistranslation occurrences in second codon position as well as the frequency of amino acids. Thus PAM(74-100) is not a suitable substitution matrix for the studies conducted on the evolution of the genetic code. 相似文献
33.
34.
Pythium oligandrum Drechsler bearing spherical sporangia with complex subglobose elements was isolated for the first time
in Egypt from agricultural field soil cultivated with alfalfa (Trifolium alexandrinum) in El-Minia, Egypt. This fungus was
found to be an active bio-control agent against P. ultimum var. ultimum, the damping-off organism of wheat. In agar plates,
P. oligandrum parasitized P. ultimum var. ultimum hyphae with the aid of thin haustorial branches or infection pegs, eventually
leading to host destruction. Incorporation of P. oligandrum into carboxymethylcellulose seed coating successfully eliminated
pre-emergence damping-off of wheat caused by P. ultimum var. ultimum, whereas Post-emergence damping-off was prevented by
adding inocula of P. oligandrum to the soil.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
35.
36.
Ghada Baraket Khaled Chatti Olfa Saddoud Ahmed Ben Abdelkarim Messaoud Mars Mokhtar Trifi Amel Salhi Hannachi 《Plant Molecular Biology Reporter》2011,29(1):171-184
This study characterises the genetic variability of fig, Ficus carica L., using simple sequence repeat (SSR) and amplified fragment length polymorphism (AFLP) markers. It compares the efficiency
and utility of the two techniques in detecting variation and establishing genetic relationships among Tunisian fig cultivars.
Our results show that using both marker systems, the Tunisian fig germ plasm is characterised by having a large genetic diversity
at the deoxyribonucleic acid level, as most of AFLP bands were detected and all SSR markers were polymorphic. In fact, 351
(342 polymorphic) and 57 (57 polymorphic) bands were detected using AFLP and SSR primers, respectively. SSR markers were the
most polymorphic with an average polymorphic information content value of 0.94, while AFLP markers showed the highest effective
multiplex ratio (56.9) and marker index (45.2). The effective marker index was recorded highest (4.19) for AFLP markers and
lowest (0.70) for the SSR ones. Our results demonstrate that (1) independent as well as combined analyses of cluster analyses
of SSR and AFLP fragments showed that cultivars are clustered independently from their geographical origin, horticultural
classifications and tree sex; (2) the analysis of molecular variance allowed the partitioning of genetic variation within
and among fig groups and showed greater variation within groups and (3) AFLP and SSR markers datasets showed positive correlation.
This study suggests the SSR and AFLP markers are suitable for diversity analysis and cultivars fingerprinting. An understanding
of the genetic diversity and population structure of F. carica in Tunisia can also provide insight into the conservation and management of this species. 相似文献
37.
Rasha M. Reda Khaled M. Selim Hassanin M. El-Sayed M. A. El-Hady 《Probiotics and antimicrobial proteins》2018,10(4):692-703
Fish gut bacteria can be used as probiotics for aquaculture. The aim of this study is to screen and identify beneficial probiotic bacteria from the gut of Nile tilapia, Oreochromis niloticus. Nine out of one hundred thirty-five isolates were non-pathogenic through intraperitoneal injection and had antibacterial activities with at least a strain from the five isolated fish pathogens, Aeromonas sobria, Aeromonas hydrophila, Pseudomonas aeruginosa, Pseudomonas putida, and Staphylococcus aureus. Further tests showed that such isolates can survive in the presence of high bile concentration (10%) and at different acidic pH values. A strains (14HT) was sensitive to all selected antibiotics, two strains were (9HT and 11HT) resistant to streptomycin and three strains (9HT, 11HT and 38HT) had resistance to two antibiotics. Four isolates (11HT, 33HT, 38HT and 41HT) had an amylase and a protease activities and one strain (47HT) showed only amylase activity. Based on 16S rRNA gene analysis, the isolated strains were identified as follows: Lactococcus lactis (8HT, 9HT, 11HT and 33HT); Enterococcus faecalis (14HT), Lysinibacillus sp. (38HT) and Citrobacter freundii (39HT, 41HT and 47HT). 相似文献
38.
Ines Dahmen-Ben Moussa Khaled Athmouni Haifa Chtourou Habib Ayadi Sami Sayadi Abdelhafidh Dhouib 《Journal of applied phycology》2018,30(2):931-941
Metal pollution can produce many biological effects on aquatic environments. The marine diatom Amphora subtropica and the green alga Dunaliella sp. possess a high metal absorption capacity. Nickel (Ni) removal by living cells of A. subtropica and Dunaliella sp. was tested in cultures exposed to different Ni concentrations (100, 200, 300, and 500 mg L?1). The amount of Ni removed by the microalgae increased with the time of exposure and the initial Ni concentration in the medium. The metal, which was mainly removed by bioadsorption to Dunaliella sp. cell surfaces (93.63% of total Ni (for 500 mg Ni L?1) and by bioaccumulation (80.82% of total Ni (for 300 mg Ni L?1) into Amphora subtropica cells, also inhibited growth. Exposure to Ni drastically reduced the carbohydrate and protein concentrations and increased total lipids from 6.3 to 43.1 pg cell?1, phenolics 0.092 to 0.257 mg GAE g?1 (Fw), and carotenoid content, from 0.08 to 0.59 mg g?1 (Fw), in A. subtropica. In Dunaliella sp., total lipids increased from 26.1 to 65.3 pg cell?1, phenolics from 0.084 to 0.289 mg GAE g?1 (Fw), and carotenoid content from 0.41 to 0.97 mg g?1 (Fw). These compounds had an important role in protecting the algae against ROS generated by Ni. In order to cope with Ni stress shown by the increase of TBARS level, enzymatic (SOD, CAT, and GPx) ROS scavenging mechanisms were induced. 相似文献
39.
Michael E. Matheny Josh F. Peterson Svetlana K. Eden Adriana M. Hung Theodore Speroff Khaled Abdel-Kader Sharidan K. Parr T. Alp Ikizler Edward D. Siew 《PloS one》2014,9(8)
Background
Patients with hospitalized acute kidney injury (AKI) are at increased risk for accelerated loss of kidney function, morbidity, and mortality. We sought to inform efforts at improving post-AKI outcomes by describing the receipt of renal-specific laboratory test surveillance among a large high-risk cohort.Methods
We acquired clinical data from the Electronic health record (EHR) of 5 Veterans Affairs (VA) hospitals to identify patients hospitalized with AKI from January 1st, 2002 to December 31st, 2009, and followed these patients for 1 year or until death, enrollment in palliative care, or improvement in renal function to estimated GFR (eGFR) ≥60 L/min/1.73 m2. Using demographic data, administrative codes, and laboratory test data, we evaluated the receipt and timing of outpatient testing for serum concentrations of creatinine and any as well as quantitative proteinuria recommended for CKD risk stratification. Additionally, we reported the rate of phosphorus and parathyroid hormone (PTH) monitoring recommended for chronic kidney disease (CKD) patients.Results
A total of 10,955 patients admitted with AKI were discharged with an eGFR<60 mL/min/1.73 m2. During outpatient follow-up at 90 and 365 days, respectively, creatinine was measured on 69% and 85% of patients, quantitative proteinuria was measured on 6% and 12% of patients, PTH or phosphorus was measured on 10% and 15% of patients.Conclusions
Measurement of creatinine was common among all patients following AKI. However, patients with AKI were infrequently monitored with assessments of quantitative proteinuria or mineral metabolism disorder, even for patients with baseline kidney disease. 相似文献40.
Lajos Attila Papp Mohammadhassan Foroughbakhshfasaei Béla Fiser Péter Horváth Eszter Kiss Khaled Sekkoum Árpád Gyéresi Gabriel Hancu Béla Noszál Zoltán-István Szabó Gergő Tóth 《Chirality》2020,32(2):158-167
A direct HPLC method was developed for the enantioseparation of pantoprazole using macrocyclic glycopeptide-based chiral stationary phases, along with various methods to determine the elution order without isolation of the individual enantiomers. In the preliminary screening, four macrocyclic glycopeptide-based chiral stationary phases containing vancomycin (Chirobiotic V), ristocetin A (Chirobiotic R), teicoplanin (Chirobiotic T), and teicoplanin-aglycone (Chirobiotic TAG) were screened in polar organic and reversed-phase mode. Best results were achieved by using Chirobiotic TAG column and a methanol-water mixture as mobile phase. Further method optimization was performed using a face-centered central composite design to achieve the highest chiral resolution. Optimized parameters, offering baseline separation (resolution = 1.91 ± 0.03) were as follows: Chirobiotic TAG stationary phase, thermostated at 10°C, mobile phase consisting of methanol/20mM ammonium acetate 60:40 v/v, and 0.6 mL/min flow rate. Enantiomer elution order was determined using HPLC hyphenated with circular dichroism (CD) spectroscopy detection. The online CD signals of the separated pantoprazole enantiomers at selected wavelengths were compared with the structurally analogous esomeprazole enantiomer. For further verification, the inline rapid, multiscan CD signals were compared with the quantum chemically calculated CD spectra. Furthermore, docking calculations were used to investigate the enantiorecognition at molecular level. The molecular docking shows that the R-enantiomer binds stronger to the chiral selector than its antipode, which is in accordance with the determined elution order on the column—S- followed by the R-isomer. Thus, combined methods, HPLC-CD and theoretical calculations, are highly efficient in predicting the elution order of enantiomers. 相似文献