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121.
Nouran Abd-ElMoemen Ahmed Menshawy Ahmed Negida Marwa Alaa El-Din Ahmed Kamel Alaa Ehab Farouk 《International journal of peptide research and therapeutics》2016,22(1):135-141
One of the current international public health emergencies is the outbreak of Ebola virus disease (EVD), requiring extraordinary response. The current outbreak in West Africa is the most dangerous since Ebola was first discovered on 26 August 1976. Till January 6th 2015, It resulted in 13,387 laboratory confirmed human cases and 8274 deaths. Ebola virus has 5 strains, 4 are pathogenic in humans while the 5th strain Ebola reston strain is not. The current outbreak is caused by Ebola most pathogenic strain, Ebola Zaire strain whose genome differs from that of Reston Ebola virus strain, by the existence of several open reading frames containing large numbers of UGA codons. These codons act as stop codons and in addition they may encode for Selenocysteine, the 21st aminoacid, which is essential for the formation of Selenoproteins. Selenoproteins are integral to the metabolism and have been linked to the progression of certain viral diseases. In this review, we discuss the relation between Selenium and the progression of the current EVD in Africa supported by geographical distribution of Se and genetic evidence. 相似文献
122.
Mahmoud S. Abdelbaset Mohamed Abdel-Aziz Mohamed Ramadan Mostafa H. Abdelrahman Syed Nasir Abbas Bukhari Taha F.S. Ali Gamal El-Din A. Abuo-Rahma 《Bioorganic & medicinal chemistry》2019,27(6):1076-1086
Novel thienoquinoline carboxamide-chalcone derivatives were prepared via the cyclization of acylated chalcones and 2-mercaptoquinoline-3-carbaldehyde in DMF with K2CO3. Thienoquinolines 9a–f, h exhibited promising antiproliferative effect against all the tested cell lines and gave a significant activity as EGFR inhibitors, with IC50 values ranging from 0.5 and 3.2?µM, and compounds 9e and 9f being the most active of the series. They also showed better activity than Erlotinib against melanoma cancer cell line A375. Moreover, compound 9f influenced pre G1 apoptosis and cell cycle arrest at G2/M phase. The binding mode of the best EGFR inhibitor 9e in the EGFR active site revealed that the thienoquinoline ring occupied the ATP-binding site while the chalcone moiety is located in the allosteric site and is responsible for the enhanced activity of these compounds. 相似文献
123.
Equine arteritis virus (EAV) induces apoptosis in infected cells. Cell death caused by EAV has been studied mainly using three cell lines, BHK-21, RK-13 and Vero cells. The mechanism of apoptosis varies among cell lines and results cannot be correlated owing to differences in EAV strains used. We evaluated different markers for apoptosis in BHK-21, RK-13 and Vero cell lines using the Bucyrus EAV reference strain. Acridine orange/ethidium bromide staining revealed morphological changes in infected cells, while flow cytometry indicated the extent of apoptosis. We also observed DNA fragmentation, but the DNA ladder was detected at different times post-infection depending on the cell line, i.e., 48, 72 and 96 h post-infection in RK-13, Vero and BHK-21 cells, respectively. Measurement of viral titers obtained with each cell line indicated that apoptosis causes interference with viral replication and therefore decreased viral titers. As an unequivocal marker of apoptosis, we measured the expression of caspase-3 and caspases-8 and -9 as extrinsic and intrinsic markers of apoptosis pathways, respectively. Caspase-8 in BHK-21 cells was the only protease that was not detected at any of the times assayed. We found that Bucyrus EAV strain exhibited a distinctive apoptosis pathway depending on the cell line. 相似文献
124.
Heba A. Hassan Mohamed Abdel-Aziz Gamal El-Din A.A. Abuo-Rahma Hassan H. Farag 《Bioorganic & medicinal chemistry》2009,17(4):1681-1692
A group of 1-malonyl-1,4-dihydropyridine derivatives were synthesized as novel carrier systems for site-specific and sustained drug delivery to the brain. Such carriers are expected to be stable against air oxidation due to the presence of the carbonyl group close to nitrogen of the dihydropyridine. These carrier systems were attached to a group of different aldehydes to afford novel quaternary pyridinium derivatives 9a–e, 11a–d, 13 and 18a–b. Reduction of the prepared quaternary pyridinium derivatives with sodium dithionite afforded a novel group of 1-malonyl-1,4-dihydropyridine chemical delivery systems (CDSs) 10a–e, 12a–d, 14 and 19a–b. The synthesized 1-malonyl-1,4-dihydropyridine CDSs were subjected to various chemical and biological investigations to evaluate their ability to cross the blood–brain barrier, and to be oxidized biologically into their corresponding quaternary derivatives. The in vitro oxidation studies showed that most of the 1-malonyl-1,4-dihydropyridine CDSs could be oxidized into their corresponding quaternary derivatives at an adequate rate. The in vivo studies showed that compounds 10c and 14 were able to cross the blood–brain barrier at detectable concentrations. Moreover, the pyridinium quaternary intermediates 9a, 9c, 13, 18a and their corresponding dihydro derivatives 10a, 10c, 14 and 19a were screened for their antidepressant activity using tail suspension behavioral despair test compared to imipramine as a reference at a dose level of 10 mg/kg. The results indicated that compounds 13, 14 and 19a induced remarkable antidepressant activity comparable to imipramine. Compounds 10a, 10c and 18a exhibited good antidepressant activity, their activities nearly equal to 92.8%, 86.7% and 90.20% of the activity of imipramine, respectively. The other derivatives 9a and 9c exhibited moderate antidepressant activity compared with imipramine. 相似文献
125.
Al-Saleh I Shinwari N Mashhour A Mohamed Gel-D Ghosh MA Shammasi Z Al-Nasser A 《Biological trace element research》2006,112(1):13-29
The association between elevated blood pressure and blood cadmium and mercury levels was examined (2001–2002) in 185 Saudi
women previously selected for a case-control study of lead and hypertension risk. Blood pressure was measured twice according
to the World Health Organization recommendations. Cadmium and mercury were determined with graphite furnace and hydride system-atomic
absorption spectrometry, respectively. Mean blood cadmium concentrations were 0.874±0.995 μg/L in hypertensive and 0.785±0.665
μg/L in controls. While blood mercury concentrations for hypertensives and controls were 3.506±3.617 μg/L and 3.687±3.186
μg/L, respectively. Participants were classified according to the median of blood cadmium and mercury levels. After adjustment
for potentially confounding variables, the final logistic regression analyses revealed that women with blood cadmium ≥0.627
μg/L were 3.934 times were more likely to be hypertensive than those with blood cadmium levels <0.627 μg/L, although this
was marginally significant (p=0.098). This was likely the result of the small number of subjects, resulting in the weak power to detect a strong significant
difference between hypertensives and control cases. On the other hand, the final regression model showed no association between
hypertension and mercury. However, this finding should not be conclusive because of the inappropriate choice of the biomarker
indicator. Nevertheless, our study supports the hypothesis that exposure to cadmium might increase the risk of hypertension. 相似文献
126.
杨善元 《植物生理与分子生物学学报》1989,15(1):83-87
叶绿素b由单体聚合成多聚体后吸收光谱明显红移。叶绿素b聚集体膜在光下产生150 mV的光电位,停止照光后此电位消失速度比叶绿素a聚集体膜的慢。叶绿素b聚集体吸收光能后形成相当稳定的能化态,半生命期约几分钟。当聚集体解聚时所吸收的光能又以光的形式辐射出来。叶绿素b聚集体能化态的能量可快速而有效地传给叶绿素a聚集体,以叶绿素a的延迟发光形式释放出来。 相似文献
127.
The combined effect of Vesicular Arbuscular Mycorrhizae (VAM) and Rhizobium on the cold season legumes, lentil and faba bean,
as well as on summer legume, soybean, were studied in soils with low indeginous VA mycorrhizal spores. Inoculation of the
plant with VA mycorrhizal fungi increased the level of mycorrhizal root infection of lentil, faba bean and soybean. The inoculation
with Rhizobium had no significant effect on VA mycorrhizal infection percent, but VA mycorrhizal inoculation increased nodulation
of the three legumes.
The inoculation with Rhizobium alone significantly increased plant dry weight and N content of lentil and faba bean as well
as seed yield of soybean. VA mycorrhizal inoculation also significantly increased plant dry weight and phosphorus content
of the plants as did fertilization with superphosphate. Rock phosphate fertilization, however, had no significant effect on
plant growth or phosphorus uptake. The addition of rock phosphate in combination with VA mycorrhizal inoculation significantly
increased plant dry weight and P uptake of the plants.
The dual inoculation with both rhizobia and mycorrhizae induced more significant increases in plant dry weight, N and P content
of lentil and faba bean as well as seed yield of soybean than inoculation with either VA mycorrhizae or Rhizobium alone. 相似文献
128.
129.
The fermentation rate of rumen microorganisms obtained from a sheep fed on hay was determined at different hours after feeding. The highest rate of fermentation was obtained immediately after feeding whereas the lowest rate was always before feeding. The effect of adding glucose, sucrose, and starch alone or in combination with urea, sodium citrate, or succinic acid on the maximal fermentation rate was studied. In no case was the maximal fermentation rate greater than that obtained in the presence of concentrate and straw. An investigation on the effect of C/N ratios, dilution, and substrate concentration on the net growth of rumen microorganisms was undertaken. The highest net growth value was obtained with a C/N ratio of 16.5 to 17.5, which is the ratio found for the ration fed to the animal. It was possible to increase net growth approximately threefold by using the proper dilution and fivefold by using the proper feed concentration. 相似文献
130.
Phylogenetic relationships among prokaryotic and eukaryotic catalases 总被引:13,自引:1,他引:12
Seventy-four catalase protein sequences, including 29 bacterial, 8 fungal,
7 animal, and 30 plant sequences, were compiled, and 70 were used for
phylogenetic reconstruction. The core of the resulting tree revealed
unique, separate groups of plant and animal catalases, two groups of fungal
catalases, and three groups of bacterial catalases. The only overlap of
kingdoms occurred within one branch and involved fungal and bacterial
large-subunit enzymes. The other fungal branch was closely linked to the
group of animal enzymes. Group I bacterial catalases were more closely
related to the plant enzymes and contained such diverse taxa as the
Gram-positive Listeria seeligeri, Deinocococcus radiodurans, and
gamma-proteobacteria. Group III bacterial sequences were more closely
related to fungal and animal sequences and included enzymes from a broad
range of bacteria including high- and low-GC Gram positives,
proteobacteria, and a bacteroides species. Group II was composed of
large-subunit catalases from diverse sources including Gram positives
(low-GC Bacilli and high-GC Mycobacteria), proteobacteria, and species of
the filamentous fungus Aspergillus. These data can be interpreted in terms
of two gene duplication events that produced a minimum of three catalase
gene family members that subsequently evolved in response to environmental
demands. Horizontal gene transfer may have been responsible for the group
II mixture of bacterial and fungal large-subunit catalases.
相似文献