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1.
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
2.
K. Kamel M. Umar W. Ibrahim A. Mansour F. Gaballah O. Selim A. Azim S. Hamza F. Sabry N. Moafy A. El-Naggar K. Hoerman 《American journal of physical anthropology》1975,43(1):103-111
Anthropological studies were done on 1276 Libyans from the Mediterranean cities of Tripoli and Benghazi, and from Sabha southward in The Sahara. The incidences of hemoglobin (Hb)-S and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency were low in the coastal areas and significantly high in Sabha. Hb-C occurred sporadically in Tripoli and Sabha, and was absent from Benghazi in the east. One case of Hb-J Benghazi was noted. There were no significant differences in the ABO blood group and Rh0 (D) type distributions in the three localities. G-6-PD gene GdA frequency was significantly high in Sabha. The lowest value of 6-phosphogluconate dehydrogenase (6-PGD) gene PGDA frequency and highest value of the gene PGDC were in Sabha. Adenylate kinase (AK) gene AK2 was only detectable in Tripoli. Acid phosphatase (AP) gene Pa frequency in Sabha was more than twice that in Tripoli and Benghazi, while Pc was distinctly lower in Sabha than in the northern cities. Haptoglobin gene Hp1 frequency was almost identical in all areas. Anthropometric measurements revealed overall homogeneity of the three samples, closer similarity in the coastal region to adjacent North African populations, and Negroid influence in the Saharan Libyans. Anthropometry substantiated findings from blood markers. 相似文献
3.
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.4.
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
5.
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
6.
Habibzadeh Seyyedeh Zahra Salehzadeh Ali Moradi-Shoeili Zeinab Shandiz Seyed Ataollah Sadat 《Molecular biology reports》2020,47(3):1637-1647
Molecular Biology Reports - Gastric cancer is one of the common types of cancer around the world which has few therapeutic options. Nitrogen heterocyclic derivatives such as thiazoles are used as... 相似文献
7.
Kobra Omidfar Fatemeh Sadat Amjad Zanjani Arghavan Golbaz Hagh Maedeh Darziani Azizi Seyed Javad Rasouli Susan Kashanian 《Molecular biology reports》2013,40(12):6737-6745
Epidermal growth factor receptor (EGFR) is deemed to be one of the main molecular targets for diagnosis and treatment of cancer. It has been identified that EGFR involves in pathogenesis of some forms of human cancers. Monoclonal antibodies targeting EGFR could control the tumor cell growth, proliferation, and apoptosis by suppressing the signal transduction pathways. Nanobodies can be regarded as the smallest intact antigen binding fragments, derived from heavy chain-only antibodies existing in camelids. Here, we describe the identification of an EGFR-specific nanobody, referred to as OA-cb6, obtained from immunized camel with a cell line expressing high levels of EGFR. Utilizing flow cytometry (FACS) and blotting methods, we demonstrated that OA-cb6 nanobody binds specifically to EGFR expressing on the surface of A431 cells. In addition, OA-cb6 nanobody potently causes the inhibition of EGFR over expression, cell growth and proliferation. The antibody fragments can probably be regarded as worthwhile binding block for further rational design of anti-cancer therapy. 相似文献
8.
Yimei Jia Dongling Zhang Robert Monette Umar Iqbal Maria Moreno 《Journal of liposome research》2013,23(4):305-314
AbstractArchaeosomes composed of archaeal total polar lipids (TPL) or semi-synthetic analog vesicles have been used as vaccine adjuvants and delivery systems in animal models for many years. Typically administered by intramuscular or subcutaneous injections, archaeosomes can induce robust, long-lasting humoral and cell-mediated immune responses against entrapped antigens and provide protection in murine models of infectious disease and cancer. Herein, we evaluated various archaeosomes for transdermal delivery, since this route may help eliminate needle-stick injuries and needle re-use, and therefore increase patient compliance. Archaeosomes composed of TPL from different archaea (Halobacterium salinarum, Methanobrevibacter smithii, Haloferax volcanii) and various semi-synthetic glycolipid combinations were evaluated for their ability to diffuse across the skin barrier using an ex vivo pig skin model and the results were compared to conventional synthetic ester liposomes. Physicochemical characteristics were determined for selected formulations including vesicle size, size distribution, zeta potential, fluidity, antigen (ovalbumin) incorporation efficiency and release. Archaeosomes, in particular those composed of M. smithii TPL or the synthetic glycolipid sulfated S-lactosylarchaeol (SLA) mixed with uncharged glycolipid lactosyl archaeol (LA), appeared to be effective carriers for ovalbumin, achieving much better antigen distribution and vesicle accumulation in the skin epidermis than conventional liposomes. The enhanced skin permeation of archaeosomes may be attributed to their chemical structure and physicochemical properties such as particle size, surface charge, stability, and fluidity of their lipid bilayer. 相似文献
9.
Zhongzhao Teng Umar Sadat Wenkai Wang Nasim S. Bahaei Shengyong Chen Victoria E. Young Martin J. Graves Jonathan H. Gillard 《PloS one》2013,8(4)
Background
Stretch is a mechanical parameter, which has been proposed previously to affect the biological activities in different tissues. This study explored its utility in determining plaque vulnerability.Methods
One hundred and six patients with mild to moderate carotid stenosis were recruited in this study (53 symptomatic and 53 asymptomatic). High resolution, multi-sequence magnetic resonance (MR) imaging was performed to delineate various plaque components. Finite element method was used to predict high stretch concentration within the plaque.Results
During a two-year follow-up, 11 patients in symptomatic group and 3 in asymptomatic group experienced recurrent cerebrovascular events. Plaque stretch at systole and stretch variation during one cardiac cycle was greater in symptomatic group than those in the asymptomatic. Within the symptomatic group, a similar trend was observed in patients with recurrent events compared to those without.Conclusion
Plaques with high stretch concentration and large stretch variation are associated with increased risk of future cerebrovascular events. 相似文献10.
The advantage of laser‐capture microdissection over whole tissue analysis in proteomic profiling studies 下载免费PDF全文
Tommaso De Marchi Rene B. H. Braakman Christoph Stingl Martijn M. van Duijn Marcel Smid John A. Foekens Theo M. Luider John W. M. Martens Arzu Umar 《Proteomics》2016,16(10):1474-1485
Laser‐capture microdissection (LCM) offers a reliable cell population enrichment tool and has been successfully coupled to MS analysis. Despite this, most proteomic studies employ whole tissue lysate (WTL) analysis in the discovery of disease biomarkers and in profiling analyses. Furthermore, the influence of tissue heterogeneity in WTL analysis, nor its impact in biomarker discovery studies have been completely elucidated. In order to address this, we compared previously obtained high resolution MS data from a cohort of 38 breast cancer tissues, of which both LCM enriched tumor epithelial cells and WTL samples were analyzed. Label‐free quantification (LFQ) analysis through MaxQuant software showed a significantly higher number of identified and quantified proteins in LCM enriched samples (3404) compared to WTLs (2837). Furthermore, WTL samples displayed a higher amount of missing data compared to LCM both at peptide and protein levels (p‐value < 0.001). 2D analysis on co‐expressed proteins revealed discrepant expression of immune system and lipid metabolisms related proteins between LCM and WTL samples. We hereby show that LCM better dissected the biology of breast tumor epithelial cells, possibly due to lower interference from surrounding tissues and highly abundant proteins. All data have been deposited in the ProteomeXchange with the dataset identifier PXD002381 ( http://proteomecentral.proteomexchange.org/dataset/PXD002381 ). 相似文献