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1.
Bakr Mohamed El-Zawahry Omar Ahmed AzzamNagla Sameh Zaki Heba Mohamed Abdel-RaheemDalia Ahmed Bassiouny Mervat Mamdooh Khorshied 《Gene》2013
PTPN22 1858C>T gene polymorphism has been associated with several autoimmune disorders including alopecia areata. The aim of the current study was to investigate the effect of the inherited genetic polymorphism 1858C>T of PTPN22 gene on the predisposition to severe forms of alopecia areata and its effect on the response to DPC treatment. To achieve our aim, PTPN22 1858C>T genotyping was performed by PCR-based restricted fragment length polymorphism (PCR-RFLP) analysis. The study included 103 Egyptian patients with extensive alopecia areata treated by DPC. Hundred healthy age and sex matched blood donors were included in the current study as a control group. Results of genotyping showed that PTPN22 CT and TT mutant genotypes were significantly higher in AA patients compared to controls and conferred increase risk of AA (OR = 2.601, 95% CI = 1.081–6.255). Statistical comparison between AA patients with wild and mutant genotypes revealed that the duration of the illness was significantly longer in those harboring the mutant genotypes. Moreover, the association of other autoimmune diseases as atopy and diabetes mellitus was higher in patients with mutant genotypes. Furthermore, PTPN22 1858C>T genetic polymorphism did not affect the patients' response to DPC immunotherapy. 相似文献
2.
Shymaa Enany Yutaka Yoshida Sameh Magdeldin Xu Bo Ying Zhang Mohamed Enany Tadashi Yamamoto 《Microbiological research》2013,168(8):504-511
Two-dimensional electrophoresis (2DE) combined with mass spectrometry was used to characterize the exo-proteome secreted by two strains (ER13 and ER21) representing community acquired methicillin resistant Staphylococcus aureus (CA-MRSA) belonging to clonal complex 80 (CC80). Common spots were detected between the 2 gels using the Progenesis SameSpots software. Two hundred and fifty-one and 312 spots from the exo-proteome of ER13 and ER21 were resolved, respectively. 2DE overlap comparison showed that 59 spots were shared. LC–MS/MS analysis identified 57 proteins from these spots comprising about 21% extracellular, 48% cytoplasmic, 2% cytoplasmic membrane, 2% cell wall, and 26% with unknown localization. The identified proteins were classified with respect to their Gene Ontology (GO) annotation as ~24% virulence determinants and toxins, ~17% involved in carbohydrate metabolism, ~14% involved in environmental stress, and ~12% associated with cell division. The identification of the enterotoxin B from the exo-products of both strains used in our study, as belonging to CC80 was interesting. 相似文献
3.
In the present study, photosynthetic parameters including gas exchanges, pigment contents, and chlorophyll fluorescence, were compared in two contrasting local Medicago truncatula lines TN6.18 and TN8.20, in response to salt added to the nutrient solution. Plants were cultivated under symbiotic nitrogen fixation (SNF) after inoculation with a reference strain Sinorhizobium meliloti 2011, a very tolerant strain to salinity (700 mM NaCl), and grown in a controlled glasshouse. On one month old plants (with active SNF), salt treatment (75 mM NaCl) was gradually applied. Photosynthesis, assimilating pigments and chlorophyll fluorescence were monitored throughout the experiment during both short and long terms, compared to control (non-saline) conditions. A genotypic variation in salt tolerance was found; TN6.18 was the more sensitive to salinity. The relative tolerance of TN8.20 was concomitant with the highest photochemical quenching coefficient (qP) affecting the maximum quantum yield of PSII (Y); the real quantum yield (?exc) was the most affected in the sensitive line. Moreover, stomatal and PSII reaction centers activities differed clearly between the studied lines. We found that the effect of salinity on photosynthesis of M. truncatula was related to PSII activity reduction rather than to stomatal conductance limitation. Photosynthesis was reduced by the inhibition of CO2 assimilation caused by PSII damage. This was clearly estimated by the Y, ?exc and especially by the quantum yield of electron transport of PSII (ΦPSII). Thus, on the basis of our results on the two local M. truncatula lines, we recommend the use of chlorophyll fluorescence as non-destructive screening method to discriminate susceptible and resistant legumes to salt stress. 相似文献
4.
Amanda Linkous Demosthenes Balamatsias Matija Snuderl Lincoln Edwards Ken Miyaguchi Teresa Milner Batsheva Reich Leona Cohen-Gould Andrew Storaska Yasumi Nakayama Emily Schenkein Richa Singhania Stefano Cirigliano Tarig Magdeldin Ying Lin Gouri Nanjangud Kalyani Chadalavada David Pisapia Howard A. Fine 《Cell reports》2019,26(12):3203-3211.e5
5.
Unrestricted modification search reveals lysine methylation as major modification induced by tissue formalin fixation and paraffin embedding 下载免费PDF全文
Bo Xu Yutaka Yoshida Oliver Horlacher Frederic Nikitin Samuel Garessus Sameh Magdeldin Naohiko Kinoshita Hidehiko Fujinaka Eishin Yaoita Miki Hasegawa Frederique Lisacek Tadashi Yamamoto 《Proteomics》2015,15(15):2568-2579
Formalin‐fixed paraffin‐embedded (FFPE) tissue is considered as an appropriate alternative to frozen/fresh tissue for proteomic analysis. Here we study formalin‐induced alternations on a proteome‐wide level. We compared LC‐MS/MS data of FFPE and frozen human kidney tissues by two methods. First, clustering analysis revealed that the biological variation is higher than the variation introduced by the two sample processing techniques and clusters formed in accordance with the biological tissue origin and not with the sample preservation method. Second, we combined open modification search and spectral counting to find modifications that are more abundant in FFPE samples compared to frozen samples. This analysis revealed lysine methylation (+14 Da) as the most frequent modification induced by FFPE preservation. We also detected a slight increase in methylene (+12 Da) and methylol (+30 Da) adducts as well as a putative modification of +58 Da, but they contribute less to the overall modification count. Subsequent SEQUEST analysis and X!Tandem searches of different datasets confirmed these trends. However, the modifications due to FFPE sample processing are a minor disturbance affecting 2–6% of all peptide‐spectrum matches and the peptides lists identified in FFPE and frozen tissues are still highly similar. 相似文献
6.
Daniela Vullo Sonia Del Prete Sameh M. Osman Zeid AlOthman Clemente Capasso William A. Donald Claudiu T. Supuran 《Bioorganic & medicinal chemistry letters》2017,27(1):77-80
Activation of the γ-class carbonic anhydrase (CAs, EC 4.2.1.1) from the pathogenic bacterium Burkholderia pseudomallei (BpsγCA) with a series of natural and non-natural amino acids and aromatic/heterocyclic amines has been investigated. The best BpsγCA activators were d-His, l-DOPA, d-Trp, 4-amino-l-Phe, dopamine, 2-(2-aminoethyl)pyridine, 2-aminoethyl-piparazine/morpholine and l-adrenaline, which showed activation constants ranging between 9 and 86 nM. The least effective activators were l-His, l-Phe and 2-pyridyl-methylamine, with KAs in the range of 1.73–24.7 μM. As little is known about the role of γ-CAs in the lifecycle and virulence of this saprophytic bacterium, this study may shed some light on such phenomena. This is the first CA activation study of a γ-CA from a pathogenic bacterium, the only other such study being on the enzyme discovered in the archaeon Methanosarcina thermophila, Cam. 相似文献
7.
Murat Bozdag Silvia Bua Sameh M. Osman Zeid AlOthman 《Journal of enzyme inhibition and medicinal chemistry》2017,32(1):885-892
A series of new derivatives was prepared by derivatisation of the 7-amino moiety present in 7-amino-3,4-dihydroquinolin-2(1H)-one, a compound investigated earlier as CAI. The derivatisation was achieved by: i) reaction with arylsulfonyl isocyanates/aryl isocyanates; (ii) reaction with fluorescein isothiocyanate; (iii) condensation with substituted benzoic acids in the presence of carbodiimides; (iv) reaction with 2,4,6-trimethyl-pyrylium tetrafluoroborate; (v) reaction with methylsulfonyl chloride and (vi) reaction with maleic anhydride. The new compounds were assayed as inhibitors of four carbonic anhydrases (CA, EC 4.2.1.1) human (h) isoforms of pharmacologic relevance, the cytosolic hCA I and II, the membrane-anchored hCA IV and the transmembrane, tumour-associated hCA IX. hCA IX was the most inhibited isoform (KIs ranging between 243.6 and 2785.6?nm) whereas hCA IV was not inhibited by these compounds. Most derivatives were weak hCA I and II inhibitors, with few of them showing KIs?10?µm. Considering that the inhibition mechanism with these lactams is not yet elucidated, exploring a range of such derivatives with various substitution patterns may be useful to identify leads showing isoform selectivity or the desired pharmacologic action. 相似文献
8.
Sonia Del Prete Rosa Perfetto Mosè Rossi Fatmah A. S. Alasmary Sameh M. Osman Zeid AlOthman 《Journal of enzyme inhibition and medicinal chemistry》2017,32(1):1120-1128
The carbonic anhydrase superfamily (CA, EC 4.2.1.1) of metalloenzymes is present in all three domains of life (Eubacteria, Archaea, and Eukarya), being an interesting example of convergent/divergent evolution, with its seven families (α-, β-, γ-, δ-, ζ-, η-, and θ-CAs) described so far. CAs catalyse the simple, but physiologically crucial reaction of carbon dioxide hydration to bicarbonate and protons. Recently, our groups characterised the α-CA from the thermophilic bacterium, Sulfurihydrogenibium yellowstonense finding a very high catalytic activity for the CO2 hydration reaction (kcat?=?9.35?×?105?s?1 and kcat/Km?=?1.1?×?108?M?1?s?1) which was maintained after heating the enzyme at 80?°C for 3?h. This highly thermostable SspCA was covalently immobilised within polyurethane foam and onto the surface of magnetic Fe3O4 nanoparticles. Here, we describe a one-step procedure for immobilising the thermostable SspCA directly on the surface membrane of Escherichia coli, using the INPN domain of Pseudomonas syringae. This strategy has clear advantages with respect to other methods, which require as the first step the production and the purification of the biocatalyst, and as the second step the immobilisation of the enzyme onto a specific support. Our results demonstrate that thermostable SspCA fused to the INPN domain of P. syringae ice nucleation protein (INP) was correctly expressed on the outer membrane of engineered E. coli cells, affording for an easy approach to design biotechnological applications for this highly effective thermostable catalyst. 相似文献
9.
Ebru Ercan Sameh Eid Christian Weber Alexandra Kowalski Maria Bichmann Annika Behrendt Frank Matthes Sybille Krauss Peter Reinhardt Simone Fulle Dagmar E. Ehrnhoefer 《Molecular neurodegeneration》2017,12(1):87
Background
Tau is a microtubule-binding protein, which is subject to various post-translational modifications (PTMs) including phosphorylation, methylation, acetylation, glycosylation, nitration, sumoylation and truncation. Aberrant PTMs such as hyperphosphorylation result in tau aggregation and the formation of neurofibrillary tangles, which are a hallmark of Alzheimer’s disease (AD). In order to study the importance of PTMs on tau function, antibodies raised against specific modification sites are widely used. However, quality control of these antibodies is lacking and their specificity for particular modifications is often unclear.Methods
In this study, we first designed an online tool called ‘TauPTM’, which enables the visualization of PTMs and their interactions on human tau. Using TauPTM, we next searched for commercially available antibodies against tau PTMs and characterized their specificity by peptide array, immunoblotting, electrochemiluminescence ELISA and immunofluorescence technologies.Results
We demonstrate that commercially available antibodies can show a significant lack of specificity, and PTM-specific antibodies in particular often recognize non-modified versions of the protein. In addition, detection may be hindered by other PTMs in close vicinity, complicating the interpretation of results. Finally, we compiled a panel of specific antibodies and show that they are useful to detect PTM-modified endogenous tau in hiPSC-derived neurons and mouse brains.Conclusion
This study has created a platform to reliably and robustly detect changes in localization and abundance of post-translationally modified tau in health and disease. A web-based version of TauPTM is fully available at http://www.tauptm.org.10.
Alia A. Badawi Samia A. Nour Wedad S. Sakran Shereen Mohamed Sameh El-Mancy 《AAPS PharmSciTech》2009,10(4):1081-1084
Microemulsions (MEs) are clear, thermodynamically stable systems. They were used to solubilize drugs and to improve topical
drug availability. Salicylic acid (SA) is a keratolytic agent used in topical products with antimicrobial actions. The objective
of this work was to prepare and evaluate SA ME systems. Different concentrations of SA were incorporated in an ME base composed
of isopropyl myristate, water, and Tween 80: propylene glycol in the ratio of 15:1. Three ME systems were prepared: S2%, S5%, and S10% which contain 2%, 5%, and 10% of SA, respectively. Evaluation by examination under cross-polarizing microscope, measuring
of percent transmittance, pH measurement, determination of the specific gravity, assessment of rheological properties, and
accelerated stability study were carried out. The data showed that the addition of SA markedly affected the physical properties
of the base. All systems were not affected by accelerated stability tests. Stability study for 6 months under ambient conditions
was carried out for S10%. No remarkable changes were recorded except a decrease in the viscosity value after 1 month. The results suggested that ME
could be a suitable vehicle for topical application of different concentrations of SA. 相似文献