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F Oftung T M Shinnick A S Mustafa K E Lundin T Godal A H Nerland 《Journal of immunology (Baltimore, Md. : 1950)》1990,144(4):1478-1483
Synthetic peptides have been used to exactly define a T cell epitope region from the immunogenic 18-kDa protein of Mycobacterium leprae. Four M. leprae reactive CD4+ T cell clones, isolated from two healthy individuals vaccinated with killed M. leprae, recognized a determinant initially defined by the peptide (38-50). However, fine mapping of the minimal sequence required for T cell recognition revealed heterogeneity among the T cell clones with regard to the N- and carboxyl-terminal boundaries of the epitopes recognized. MHC restriction analysis showed that the immunogenic peptides were presented to the T cells in an HLA-DR4,Dw4-restricted manner in all cases. The results suggest that a polyclonal T cell response representing different fine specificities is directed toward a possible immunodominant epitope from the M. leprae 18-kDa Ag in individuals carrying this MHC haplotype. 相似文献
14.
Sebahattin Özcan Cafer S. Sevimay Mustafa Yildiz Cengiz Sancak Murat Özgen 《Plant cell reports》1996,16(3-4):200-203
Summary Immature cotyledons and embryo axes of sainfoin were cultured on Murashige and Skoog (MS) media supplemented with various concentrations of 6-benzylaminopurine (BAP) and a-naphthaleneacetic acid (NAA) to induce adventitious shoot regeneration. The highest frequency of shoot regeneration occurred following an initial callus growth on a MS medium containing 0.5 mg/l BAP and 2 mg/l NAA. Immature embryo axes showed higher regeneration capacity than immature cotyledons, however, shoot elongation was best achieved on immature cotyledons. Regenerated shoots were excised and rooted in half strength MS medium with 1 mg/l indole-butyric acid (IBA) or 1 mg/l NAA. The rooted plantlets were finally transferred to compost. 相似文献
15.
The endoplasmic reticulum (ER) membrane protein complex (EMC) is essential for the insertion of a wide variety of transmembrane proteins into the plasma membrane across cell types. Each EMC is composed of Emc1-7, Emc10, and either Emc8 or Emc9. Recent human genetics studies have implicated variants in EMC genes as the basis for a group of human congenital diseases. The patient phenotypes are varied but appear to affect a subset of tissues more prominently than others. Namely, craniofacial development seems to be commonly affected. We previously developed an array of assays in Xenopus tropicalis to assess the effects of emc1 depletion on the neural crest, craniofacial cartilage, and neuromuscular function. We sought to extend this approach to additional EMC components identified in patients with congenital malformations. Through this approach, we determine that EMC9 and EMC10 are important for neural crest development and the development of craniofacial structures. The phenotypes observed in patients and our Xenopus model phenotypes similar to EMC1 loss of function likely due to a similar mechanism of dysfunction in transmembrane protein topogenesis. 相似文献
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Tahsin Shoala Basma H. Amin Ismail A. S. Rashid Fayz A. Abdel-Rahman Mohamed E. Khalil Khamis Youssef 《Phyton》2023,92(4):1139-1152
Production of peaches (Prunus persica (L.) Batsch) for both local market and export is increasing each year in
Egypt. Brown rot disease, caused by Monilinia laxa and Monilinia fructigena, is considered one of the most
important postharvest rots affecting peaches in Egypt and economic losses are increasing. Antifungal activity
of glycyrrhizic acid nanoparticles (GA-NPs) and glycyrrhizic acid (GA) at 0.2 and 0.4 mmol/L was investigated
as a control for both these brown rot pathogens on peach fruits in both in vitro and in vivo studies. In the in vitro
studies, GA-NPs were the most effective as shown by the ability to decrease linear growth of both brown rot
pathogens in potato dextrose agar (PDA) amended with 0.4 mmol/L GA-NPs. Micrographs of M. fructigena
exposed to 0.4 mmol/LGA showed mycelial deformations, nodule formation, detachment of the cell wall, shrinkage and inhomogeneous cytoplasmic materials with large vacuoles. Mycelium of M. laxa exposed to 0.4 mmol/
LGA-NPs resulted in thinner and distorted hyphae, nodule formation, cell wall thinning, and swellings. The GANPs and GA treatments improved fruit quality by maintaining firmness and total soluble solids (TSS). GA-NPs
were more effective in decreasing decay incidence than their bulk material. The 0.4 mmol/L GA-NPs completely
inhibited the disease on naturally infected peach fruits for both seasons of 2018 and 2019. Furthermore,
0.4 mmol/L GA-NPs reduced the disease incidence in inoculated fruits by 95 (M. laxa) and 88% (M. fructigena)
in 2018 season and 96 (M. laxa) and 85% (M. fructigena) in 2019 season. In conclusion, GA-NPs could enhance
the resistance of peaches against brown rot caused by M. laxa and M. fructigena. 相似文献
18.
S J Mustafa M M Mansour 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1984,176(1):22-26
This study was undertaken in an attempt to further understand the relationship between adenosine and H+ ion. Using Langendorff hearts from male rabbits, the perfusion fluid pH was lowered from 7.4 to 7.1 and 6.8 with CO2. A 31 and 86% increase in coronary flow with a simultaneous increase in the release of adenosine by 61 and 128% was observed at pH 7.1 and 6.8, respectively. A direct relationship between adenosine release and coronary flow with a correlation coefficient of 0.99 was found at pH values of 7.4, 7.1, and 6.8. The degradation products of adenosine namely inosine and hypoxanthine were unchanged at 7.1 and 6.8 from 7.4. These data support a role for adenosine in the regulation of coronary flow and suggest a relationship between adenosine and H+ ion. 相似文献
19.
Mustafa Kh. Dabbous Ola Hammouda Burcharda Brinkley 《Molecular and cellular biochemistry》1981,34(2):87-93
Summary Limited proteolysis with pepsin solubilized 25% of the insoluble gingival matrix as mainly soluble collagenous material. Fractional
salt precipication at neutral pH resulted in the separation of types III and I at 1.8 and 2.6 M NaCl, respectively. In addition,
a collagenous fraction accounting for 2% of the solubilized collagen and precipitating at 4.5 M NaCl was shown to be identical
with type V collagen. Isolation and partial characterization of the constituent-α-chains of the 4.5 M PPT by gel filtration,
ion exchange and hydroxylapatite chromatography as well as disc electrophoresis showed that gingival type V collagen contains
αA and αB chains in a ratio αB/αA of 1.73–1.8. Electron microscopic examination of ATP-precipitates showed that this collagen
type gave only one kind of SLS aggregates with asymmetric band pattern characteristically different from that of type I collagen.
The data provide evidence that gingival AB collagen is a heteropolymer in which the αA and αB chains are assembled in the
same macromolecule in a 1∶2 ratio. 相似文献
20.
Nabil Elsayed Allen Hacker Mohammad Mustafa Klaus Kuehn Gerhard Schrauzer 《Biochemical and biophysical research communications》1982,104(2):564-569
The effects of reducing glutathione peroxidase activity in the lung by changing dietary selenium intake has been investigated. In animals that were exposed to room air, selenium effects were confined to glutathione peroxidase activity, whereas under conditions of oxidant stress (ozone) the decrease in glutathione peroxidase activity prevented the stimulation of the pentose phosphate cycle (assayed by measuring glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase activities) which has been reported to increase in response to oxidant stress. The suppression of glutathione peroxidase activity was found to depend on dietary selenium concentration. The physiological significance of this observation may be related to the process of injury and repair in the lung. 相似文献