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121.
Essam N. Sholkamy Maged S. Ahamd Manal M. Yasser Noor Eslam 《Saudi Journal of Biological Sciences》2019,26(1)
A novel strain of Saccaropolyspora hirsuta was isolated from an insect Tapinoma simrothi for the first time and was morphologically and physiologically characterized. It was genetically identified using 16S rRNA and sequence similarity percentage in genbank with closely related species as strain ess_amA6 of Saccaropolyspora hirsuta. The accession number of strain ess_amA6 is KF996506. Antagonistic activity of strain ess_amA6 against some pathogenic Gram positive and negative bacteria, and unicellular fungus Candida albicans was studied. In addition, star shaped silver nanoparticles were biosynthesized using strain ess_amA6. The silver Nano stars were characterized by UV-us spectrophotometer. Fourier transform infrared spectroscopy analysis confirmed the conversion of Ag+ ions to Nano silver due to the reduction by capping material of extract. Transmission electron microscopically studies of biosynthesized Nano silver particles showed that they are spherical ranging from 10?nm to 30?nm in size. Silver atoms were checked in Nano sample by Energy Dispersive X-ray spectroscopy. Bioactivity of biosynthesized Nano silver was observed against some pathogenic microorganisms such as Staphylococcus aureus, Streptococcus pyogenes, Salmonella typhi, pseudomonas aeruginosa, Klebsiella pneumonia and Candida albicans. These tested microbes were highly sensitive to Nano silver. This study recommended that strain ess_amA6 can be used to effectively biosynthesize bioactive Nano silver compounds. 相似文献
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123.
Feda Aljaser Hajera Tabassum Sabiha Fatima Manal Abudawood Naheed Banu 《Saudi Journal of Biological Sciences》2021,28(8):4455-4460
The impact of trace elements, especially zinc, selenium, copper, and magnesium, on male fertility has gained great interest and significance. Increased oxidative stress and altered trace element levels are probable etiological factors underlying male reproductive dysfunction and infertility. The present study focused on the evaluation of seminal oxidative markers, such as reactive oxygen species (ROS), malondialdehyde (MDA), and total antioxidant capacity (TAC), and trace element levels in the normozoospermic fertile control group (n = 40) and asthenozoospermic infertile group (n = 30). Semen from infertile men exhibited significantly higher ROS and MDA levels accompanied with significant decline in TAC and trace element (zinc and magnesium) levels. Furthermore, a significant correlation was observed between trace elements and oxidative markers with sperm motility. The current study revealed increased lipid peroxidation and oxidant-reductant imbalance that leads to deterioration of semen quality and male infertility. Thus, oxidative stress and trace elements can be considered important biomarkers of male infertility. Measurement of seminal oxidative stress with conventional seminological parameters must be integrated in fertility assessment from early stages to ensure healthy semen characteristics and fertility in men. 相似文献
124.
Mohammad Abbas Ilanchezhian Shanmugam Manal Bsaili Robert Hromas Monte Shaheen 《The Journal of biological chemistry》2014,289(20):14009-14019
Psoralen 4 (Pso4) is an evolutionarily conserved protein that has been implicated in a variety of cellular processes including RNA splicing and resistance to agents that cause DNA interstrand cross-links. Here we show that the hPso4 complex is required for timely progression through S phase and transition through the G2/M checkpoint, and it functions in the repair of DNA lesions that arise during replication. Notably, hPso4 depletion results in delayed resumption of DNA replication after hydroxyurea-induced stalling of replication forks, reduced repair of spontaneous and hydroxyurea-induced DNA double strand breaks (DSBs), and increased sensitivity to a poly(ADP-ribose) polymerase inhibitor. Furthermore, we show that hPso4 is involved in the repair of DSBs by homologous recombination, probably by regulating the BRCA1 protein levels and the generation of single strand DNA at DSBs. Together, our results demonstrate that hPso4 participates in cell proliferation and the maintenance of genome stability by regulating homologous recombination. The involvement of hPso4 in the recombinational repair of DSBs provides an explanation for the sensitivity of Pso4-deficient cells to DNA interstrand cross-links. 相似文献
125.
Basma El Yacoubi Benjamin Lyons Yulien Cruz Robert Reddy Brian Nordin Fabio Agnelli James R. Williamson Paul Schimmel Manal A. Swairjo Valrie de Crcy-Lagard 《Nucleic acids research》2009,37(9):2894-2909
Threonylcarbamoyladenosine (t6A) is a universal modification found at position 37 of ANN decoding tRNAs, which imparts a unique structure to the anticodon loop enhancing its binding to ribosomes in vitro. Using a combination of bioinformatic, genetic, structural and biochemical approaches, the universal protein family YrdC/Sua5 (COG0009) was shown to be involved in the biosynthesis of this hypermodified base. Contradictory reports on the essentiality of both the yrdC wild-type gene of Escherichia coli and the SUA5 wild-type gene of Saccharomyces cerevisiae led us to reconstruct null alleles for both genes and prove that yrdC is essential in E. coli, whereas SUA5 is dispensable in yeast but results in severe growth phenotypes. Structural and biochemical analyses revealed that the E. coli YrdC protein binds ATP and preferentially binds RNAThr lacking only the t6A modification. This work lays the foundation for elucidating the function of a protein family found in every sequenced genome to date and understanding the role of t6A in vivo. 相似文献
126.
Researchers conduct gait analyses utilizing both overground and treadmill modes of running. Previous studies comparing these modes analyzed discrete variables. Recently, techniques involving quantitative pattern analysis have assessed kinematic curve similarity in gait. Therefore, the purpose of this study was to compare hip, knee and rearfoot 3-D kinematics between overground and treadmill running using quantitative kinematic curve analysis. Twenty runners ran at 3.35 m/s ± 5% during treadmill and overground conditions while right lower extremity kinematics were recorded. Kinematics of the hip, knee and rearfoot at footstrike and peak were compared using intraclass correlation coefficients. Kinematic curves during stance phase were compared using the trend symmetry method within each subject. The overall average trend symmetry was high, 0.94 (1.0 is perfect symmetry) between running modes. The transverse plane and knee frontal plane exhibited lower similarity (0.86-0.90). Other than a 4.5 degree reduction in rearfoot dorsiflexion at footstrike during treadmill running, all differences were ≤1.5 degrees. 17/18 discrete variables exhibited modest correlations (>0.6) and 8/18 exhibited strong correlations (>0.8). In conclusion, overground and treadmill running kinematic curves were generally similar when averaged across subjects. Although some subjects exhibited differences in transverse plane curves, overall, treadmill running was representative of overground running for most subjects. 相似文献
127.
Barakat M Elkhayat Z Kholoussi N Elnady H Ismail M Raafat J 《Journal of biochemical and molecular toxicology》2010,24(6):343-350
Apoptosis is the primary mechanism through which most chemotherapeutic agents induce tumor cell death. The purpose of this study was to monitor the expression of pro- and anti-apoptotic proteins CD(95) , Bcl-2, as well as copper and zinc levels in the peripheral blood of children with acute lymphocytic leukemia (ALL) prior to and 6 months after the beginning of chemotherapy. Blood parameters and bone marrow blast count were also assessed. Twenty of 26 patients who received treatment showed amelioration in apoptotic response, which is reflected in the elevation of CD(95) , whereas Bcl-2 protein was significantly lowered. In these patients, the elevated serum copper level was not significantly affected whereas the low serum zinc level was significantly raised. Improvement in blood parameters and bone marrow blast count were also achieved. Taken together, the data suggested that assessment of apoptosis signaling molecules might have a predictive impact on treatment outcome. 相似文献
128.
Biochemical study of the anti-diabetic action of the Egyptian plants Fenugreek and Balanites 总被引:2,自引:0,他引:2
Gad MZ El-Sawalhi MM Ismail MF El-Tanbouly ND 《Molecular and cellular biochemistry》2006,281(1-2):173-183
Fenugreek and Balanites are two plants commonly used in Egyptian folk medicine as hypoglycemic agents. In the present study,
the effects of 21 days oral administration of Fenugreek seed and Balanites fruit extracts (1.5 g/kg bw) on the liver and kidney
glycogen content and on some key liver enzymes of carbohydrate metabolism in STZ-diabetic rats were studied. In addition,
the effects of these two plant extracts on the intestinal α-amylase activity in vitro and starch digestion and absorption in vivo were also examined. Results indicated that single injection of STZ (50 mg/kg bw) caused 5-folds increase in the blood glucose
level, 80% reduction in serum insulin level, 58% decrease in liver glycogen and 7-folds increase in kidney glycogen content
as compared to the normal levels. The activity of glucose-6-phosphatase was markedly increased, whereas, the activities of
both glucose-6-phosphate dehydrogenase and phospho-fructokinase were significantly decreased in the diabetic rat liver. Administration
of Fenugreek extract to STZ-diabetic rats reduced blood glucose level by 58%, restored liver glycogen content and significantly
decreased kidney glycogen as well as liver glucose-6-phosphatase activity. Meanwhile, Balanites extract reduced blood glucose
level by 24% and significantly decreased liver glucose-6-phosphatase activity in diabetic rats. On the other hand, our results
demonstrated that both the Fenugreek and Balanites extracts were able to in vitro inhibit α-amylase activity in dose-dependent manner. Fenugreek was more potent inhibitor than Balanites. This inhibition
was reversed by increasing substrate concentration in a pattern which complies well with the effect of competitive inhibitors.
Furthermore, this in vitro inhibition was confirmed by in vivo suppression of starch digestion and absorption induced by both plant extracts in normal rats. These findings suggest that
the hypoglycemic effect of Fenugreek and Balanites is mediated through insulinomimetic effect as well as inhibition of intestinal
α-amylase activity. 相似文献
129.
Manal M. Alkhulaifi Jamilah H. Alshehri Moudi A. Alwehaibi Manal A. Awad Nouf M. Al-Enazi Noura S. Aldosari Ashraf A. Hatamleh Neveen Abdel- Raouf 《Saudi Journal of Biological Sciences》2020,27(12):3434-3441
The present work aimed to synthesis silver nanoparticles (AgNPs) using biological waste products Citrus limon peels, its characterization, antimicrobial activities and the cytotoxic effect of the synthesized green AgNPs. Characterization of the prepared AgNPs showed the formation of spherical, and few agglomerated AgNPs forms as measured by UV–visible spectrophotometer. The average size of the prepared AgNPs was 59.74 nm as measured by DLS technique. The spectrum of the synthesized AgNPs was observed at 3 KeV using the EDX. On the other hand, FTIR analysis of the green synthesized AgNPs showed the presence of alcohols, phenolics, mono-substituted alkynes, aliphatic primary amines, sodium salt, amino acid, or SiOH alcohol groups. The antimicrobial studies of the formed AgNPs showed positive activity against most of the studied human pathogenic bacteria with varying degrees. Finally, the evaluation of the cytotoxic effect of the green synthesized AgNPs were done using two types of cell lines, human breast cancer cell line (MCF-7) and human colon carcinoma cell line (HCT-116). The results revealed the concentration has a direct correlation with cell viability. The 50% inhibitory concentration (IC50) of MCF-7 cell line was in of 23.5 ± 0.97 µL/100 µL, whereas the HCT-116 cell line was in 37.48 ± 5.93 µL/100 µL. 相似文献
130.
Losartan potassium (LOS) and atorvastatin (ATR) are used in combination for long‐term treatment of stroke and for treatment of hypertension with high‐level cholesterol. Both drugs were simultaneously determined and validated using a novel, easy, fast, and economical first‐derivative synchronous fluorescence spectroscopic method. Methanol was used as the solvent for both drugs at a Δλ 80 nm and with a scanning rate of 600 nm/min. Peaks were determined as at 288.1 nm and 263.6 nm for LOS and ATR, respectively. The proposed method was validated according to International Conference on Harmonization guidelines and, subsequently, the developed method was applicable to the analysis of the two compounds in their different formulations without interference from each other. Amplitude–concentration plots were rectilinear over the concentration ranges 1.0–10.0 μg/ml and 0.5–5.0 μg/ml for LOS and ATR, respectively. Detection limits were found to be 0.096 μg/ml and 0.030 μg/ml and quantitation limits were 0.291 μg/ml and 0.093 μg/ml for LOS and ATR, respectively. The proposed method was successfully applied to the analysis of both compounds in synthetic mixtures and in laboratory‐prepared tablets. These results were in accordance with the results acquired using the comparison method, high‐performance liquid chromatography. 相似文献