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1.
A new haemoglobin variant (haemoglobin Arya), is described from an Iranian female. The substitution is at residue 47 (CD5) of the alpha chain in which aspartic acid has been substituted by asparagine. The presence of haemoglobin Arya was not associated with clinical symptoms. This variant has normal stability at 50 degrees C, but is slightly unstable when tested at 55 degrees C. 相似文献
2.
Cell cycle specificity of tumor necrosis factor and its receptor 总被引:1,自引:0,他引:1
N Watanabe Y Niitsu N Yamauchi H Neda H Sone M Maeda I Urushizaki 《Cell biology international reports》1987,11(11):813-817
Phase specificity in the TNF cytotoxic effect and the number of TNF binding receptors was investigated using L-M cells incubated synchronously from the S phase. TNF cytotoxicity was observed to occur at various levels during the cell cycle, with peak effect in the G2-M phase. Analysis with 125I-labeled TNF to determine the number of receptors binding TNF in the various cell phases shewed a phase specificity with the maximum number occurring in the G2-M phase, similar to the peak in cytotoxicity. The results suggest the existence of a cell cycle specificity in the cytotoxicity of TNF which is apparently related to changes in the number of receptors capable of binding TNF. 相似文献
3.
Neda Milinkovi Milica Zekovi Margarita Dodevska Briita orevi Branimir Radosavljevi Svetlana Ignjatovi Nevena Ivanovi 《Journal of Medical Biochemistry》2022,41(3):316
BackgroundLiterature data indicate the benefit of magnesium (Mg) supplementation. The aim of this study was to examine the effect of short-term Mg supplementation on iron status in healthy female participants.MethodsOne hundred healthy female students of the University of Belgrade - Faculty of Pharmacy participated the study during eleven intervention days. Students ingested Mg preparations with the same dose of the active substance. The analysis included the measurement of serum iron, unsaturated iron binding capacity (UIBC), total iron binding capacity (TIBC), total Mg (tMg), ionized Mg (iMg), complete blood count, met-, carboxyand oxy-haemoglobin (metHgb, COHgb, O2Hgb). Transferrin concentrations and percentage of transferrin saturation (SAT) were calculated manually. The association among the analyzed biochemical parameters was examined using polynomial regression. A principal component analysis (PCA) was used for the evaluation of interdependence between the analyzed parameters.ResultsA statistically significant trend for change in O2Hgb (%) by tertiles of iMg concentrations was found (P = 0.029). Serum tMg reached significant positive correlation with the SAT at concentration levels greater than 0.9 mmol/L, after 11 days of intervention (R2=0.116). Ionized Mg in a concentration higher than 0.6 mmol/L is positively correlated with SAT and serum Fe (R2=0.214; 0.199, respectively). PCA revealed variability of 64.7% for two axes after 11 days.ConclusionsMg supplementation leads to an improvement in the certain iron status parameters even in individuals with optimal levels of these indices. However, caution should be exercised when supplementing Mg, and laboratory monitoring of the interaction is required. 相似文献
4.
Effects of extremely low frequency magnetic field on the development of tolerance to the analgesic effect of morphine in rats 下载免费PDF全文
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Objectives
To improve the production and activity of an alkaline zinc metalloprotease from Salinivibrio proteolyticus in response to ZnSO4 (ionic and nanoparticle forms) and low intensity direct electric current (LIDC).Results
A DC of 50 µA for 10 min increased enzyme production from 35 to 53 U ml?1 when applied to the stationary phase bacterial cells. Zn2+ improved enzyme production better than zinc nanoparticles (52 vs. 43.5 U ml?1). Zinc nanoparticles (0.5 mM) added to an enzyme reaction mixture containing casein (0.65 %) and 20 mM Tris/HCl buffer (pH 8) improved enzyme activity more than Zn2+ (42 vs. 36 U ml?1).Conclusion
LIDC exposure (50 µA, 10 min) to the stationary phase bacterial cells increases metalloprotease production in Salinivibrio. A low concentration of zinc nanoparticles (0.5 mM) increases maximum enzyme activity.7.
In an attempt to increase tolerance to salinity stress in tobacco plants, the genes encoding the mutant form of glutamyl kinase
(proB), pyrroline-5-carboxylate synthetase, and osmotin were cloned into three different shuttle vectors and were separately introduced
into the tobacco plants. The transgenic lines were compared for their ability to produce shoots and grow in MS medium containing
320 mM NaCl; it was shown that the transgenic lines containing genetically handled osmotin gene are more resistant to salinity. The amount of chlorophyll a was used to show continuing growth of plant lines. The results showed that only the tobacco lines transformed with the modified
osmotin gene exhibited greater tolerance to salinity.
Published in Russian in Fiziologiya Rastenii, 2006, Vol. 53, No. 1, pp. 122–127.
The text was submitted by the authors in English. 相似文献
8.
Mehrabi Fatemeh Shamspur Tayebeh Sheibani Hassan Mostafavi Ali Mohamadi Maryam Hakimi Hamid Bahramabadi Reza Salari Elham 《Biometals》2021,34(6):1237-1246
BioMetals - Trimethoprim and sulfamethoxazole are prescribed for a broad spectrum of bacteria. However, the use of these medicines is restricted due to the risk of microbial resistance in the body.... 相似文献
9.
Hamid Tanzadehpanah Asrin Bahmani Neda Hosseinpour Moghadam Hamid Gholami Hanie Mahaki Abbas Farmany Massoud Saidijam 《Luminescence》2021,36(1):117-128
Sorafenib tosylate (SORt) is an oral multikinase inhibitor used for treatment of advanced renal cell, liver, and thyroid cancers. In this study, this drug was synthesized and its antiproliferative activities against HCT116 and CT26 cells were assessed. The interaction of SORt with β‐lactoglobulin (BLG) was studied using different fluorescence techniques, circular dichroism (CD), zeta potential measurements, and docking simulation. The results of infrared (IR), mass, HNMR, and CNMR spectra demonstrated that the drug was produced with high quality, purity, and efficiency. SORt showed potent cytotoxicity against HCT116 and CT26 cells with IC50 of 8.12 and 5.42 μM, respectively. For BLG binding of SORt, the results showed that static quenching was the cause of the high affinity drug–protein interaction. Three‐dimensional fluorescence and synchronous spectra indicated that SORt conformation was changed at different levels. CD suggested that the α‐helix content remained almost constant in the BLG–SORt complex, whereas random coil content decreased. Zeta potential values of BLG were more positive after binding with SORt, due to electrostatic interactions between BLG and SORt. Thermodynamic parameters confirmed van der Waals and hydrogen bond interactions in the complex formation. Molecular modelling predicted the presence of hydrogen bonds and electrostatic forces in the BLG–SORt system, which was consistent with the experimental results. 相似文献
10.
Seyed Nezamedin Hosseini Amin Javidanbardan Behnaz Sadat Alizadeh Salim 《Preparative biochemistry & biotechnology》2013,43(8):683-692
AbstractThe costly media, inconsistent ligand density, ligand leakage, and possible destabilization of recombinant hepatitis B surface antigen (rHBsAg) particles are main drawbacks of using immunoaffinity chromatography (IAF) in the large-scale downstream processing. In this study, we aimed to use an efficient large-scale purification system as an alternative purification method for immunoaffinity chromatography. For this purpose, we suggested integrating non-affinity chromatographic methods of hydrophobic interaction chromatography (HIC) and size-exclusion chromatography (SEC) for cost-effective purification of rHBsAg expressed in P. pastoris. The optimization of such process is not trivial and straightforward since diverse molecular characteristics of expressed rHBsAg in each type of host cell cause different interactions in non-affinity chromatography processes. The working buffer composition and chromatography parameters are the most influential factors in hydrophobic interaction chromatography. The best result for lab-scale HIC was achieved by using ammonium sulfate buffer in 10% of saturation concentration in pH 7.0 with Butyl-S Sepharose 6 Fast Flow medium and with subsequent Tween-100 and urea elution. In this process, the recovery, purity, and total yield were about 84%, 82%, and 69%, respectively. By scaling-up the HIC and integrating it with Sephacryl S-400?SEC, we obtained highly pure, i.e.,?>?90%, rHBsAg virus-like particles (VLP). 相似文献