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91.
Dilfuza Egamberdieva Stephan Wirth Abdulaziz A. Alqarawi E.F. Abd_Allah 《Saudi Journal of Biological Sciences》2015,22(5):585-590
The source of infection has always been considered as an important factor in epidemiology and mostly linked to environmental source such as surface water, soil, plants and also animals. The activity of the opportunistic pathogens associated with plant root, their adaptation and survival under hostile environmental condition is poorly understood. In this study the salt tolerance ability of Methylobacterium mesophilicum and its colonization in the root and shoot of plants under severe drought and salt stress conditions were investigated. The colonization of plant by M. mesophilicum was investigated in a gnotobiotic sand system, and their survival in pots with saline soil. Bacterial strain was found to colonize rhizosphere of cucumber, tomato and paprika grown under normal and salt stress condition and reached up to 6.4 × 104 and 2.6 × 104 CFU/g root. The strain was resistant to Gentamicin, Ampicillin, Amoxicillin plus Clavulanic acid, Cefotaxime, neomycin, penicillin and was also tolerant to salinity stress (up to 6% NaCl). These abilities play important roles in enabling persistent colonization of the plant surface by M. mesophilicum strains. In conclusion, this study provides background information on the behaviour of opportunistic pathogen M. mesophilicum on plants and their survival in harsh environmental conditions. 相似文献
92.
Majid Shahbazi Hamid Ebadi Davood Fathi Danial Roshandel Mana Mahamadhoseeni Azam Rashidbaghan Narges Mahammadi Mahammad Reza Mahammadi Mahdi Zamani 《Cellular and molecular neurobiology》2009,29(8):1205-1209
The 32-base pair deletion on the C–C chemokine receptor 5 gene (CCR5-delta32) is known as a protective allele against immune
system disorders. We have studied this variation in Iranian multiple sclerosis (MS) patients and healthy controls. DNA samples
were prepared from the whole blood of 254 patients with MS and 380 healthy controls. We amplified the fragment including the
CCR5-delta32 polymorphism and visualized the products in a documentation system after agarose gel electrophoresis. Data were
analysed using one-way ANOVA and Fisher’s exact tests with SPSS-v13 and STATA-v8 software. The delta32 allele was more frequent
in MS patients when compared with controls (OR = 2.3, P < 0.0001). Also, we found a significant difference in the frequency of the delta32/delta32 genotype among patients and controls
(OR = 7.4, P < 0.001). The mean age at onset and progression index was not significantly different between patients with various genotypes.
According to our study, the delta32 allele of the CCR5 gene might be a predisposing factor for MS development in the Iranian
population. However, there were no associations between this polymorphism and the clinical course of the disease in this study. 相似文献
93.
Embryoid bodies (EBs) are primitive embryonic structures derived from differentiating embryonic stem cells (ESCs). Many techniques
have been used to obtain EBs. Improving the technique of EB formation can help in achieving better results in ESCs differentiation
into neurons, myocardiocytes, haemopoeitic cells, and others. We evaluated the use of Sigmacote™ as a hydrophobic substrate
to improve EB formation. CCE and P19 cell lines were used to obtain EBs and retinoic acid was used to induce neural differentiation.
The results revealed that Sigmacote™, as a hydrophobic substrate, can improve EB formation from ESCs. Our results demonstrate
that the silicon-coating of glass petri dishes by Sigmacote™ is an easy and reproducible technique to enhance EB formation
from murine ESCs and EC cells. 相似文献
94.
Tarek Boussetta Houssam Raad Philippe Lettéron Marie-Anne Gougerot-Pocidalo Jean-Claude Marie Fathi Driss Jamel El-Benna 《PloS one》2009,4(7)
Background
Neutrophils play a major role in inflammation by releasing large amounts of ROS produced by NADPH-oxidase and myeloperoxidase (MPO). The proinflammatory cytokine TNFα primes ROS production through phosphorylation of the NADPH-oxidase subunit p47phox on Ser345. Conventional anti-inflammatory therapies remain partially successful and may have side effects. Therefore, regulation of neutrophil activation by natural dietary components represents an alternative therapeutic strategy in inflammatory diseases such as inflammatory bowel diseases. The aim of this study was to assess the effect of punicic acid, a conjugated linolenic fatty acid from pomegranate seed oil on TNFα-induced neutrophil hyperactivation in vitro and on colon inflammation in vivo.Methodology and Principal Findings
We analyzed the effect of punicic acid on TNFα-induced neutrophil upregulation of ROS production in vitro and on TNBS-induced rat colon inflammation. Results show that punicic acid inhibited TNFα-induced priming of ROS production in vitro while preserving formyl-methionyl-leucyl-phenylalanine (fMLP)-induced response. This effect was mediated by the inhibition of Ser345-p47phox phosphorylation and upstream kinase p38MAPK. Punicic acid also inhibited fMLP- and TNFα+fMLP-induced MPO extracellular release from neutrophils. In vivo experiments showed that punicic acid and pomegranate seed oil intake decreased neutrophil-activation and ROS/MPO-mediated tissue damage as measured by F2-isoprostane release and protected rats from TNBS-induced colon inflammation.Conclusions/Significance
These data show that punicic acid exerts a potent anti-inflammatory effect through inhibition of TNFα-induced priming of NADPH oxidase by targeting the p38MAPKinase/Ser345-p47phox-axis and MPO release. This natural dietary compound may provide a novel alternative therapeutic strategy in inflammatory diseases such as inflammatory bowel diseases. 相似文献95.
96.
97.
A precise and specific 1H-NMR method has been developed for the assay of papaverine hydrochloride (1) as a bulk drug, as well as in tablet and injection dosage forms. The assay depends upon the integration of the 12 protons of the four methoxy groups of 1 relative to that of the three methyl protons of acetanilide (internal standard). In addition to the accurate quantitative determination of 1, the method provides a specific means of identifying 1 as well as detecting other alkaloids or impurities. 相似文献
98.
Salwa Mohamed Elsayed Salama Huda A. Alazab Assem Bakry Archana Sharma Yasser Assran 《Luminescence》2024,39(1):e4679
In this work, (99 − x)CaSO4-Dy2O3–xEu2O3, (where x = 0, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5) thermoluminescence phosphors were prepared using a coprecipitation method. The thermoluminescence (TL) dosimetry (TLD) characteristics such as TL sensitivity, dose–response, minimum detectable dose, thermal fading, and the effect of sunlight on the prepared phosphors were investigated. The obtained results indicated that the most sensitive phosphor was obtained at x = 0.05. Large thermal fading of 6% after 1 h and 26% after 24 h from irradiation followed by 71% after 1 month with no additional fading was observed within a time frame exceeding 2 months throughout the remaining duration of the investigation, which also spanned over 2 months. Despite the phosphor's high fading rate, the relative sensitivity of the prepared samples was ~90% compared with TLD-100. The marked effect of day sunlight was also determined. High dose–response within the low-dose range from 0.01 to 5 Gy was observed. The obtained results suggested that the synthesized phosphor is well suited for applications involving radiation biology and radiotherapy dosimetry. 相似文献
99.
Wagdy M. Eldehna Rofaida Salem Zainab M. Elsayed Tarfah Al-Warhi Hamada R. Knany Rezk R. Ayyad Thamer Bin Traiki Maha-Hamadien Abdulla Rehan Ahmad Hatem A. Abdel-Aziz Radwan El-Haggar 《Journal of enzyme inhibition and medicinal chemistry》2021,36(1):1424
In the current work, a new set of carbohydrazide linked benzofuran-isatin conjugates (5a–e and 7a–i) was designed and synthesised. The anticancer activity for compounds (5b–d, 7a, 7b, 7d and 7g) was measured against NCI-55 human cancer cell lines. Compound 5d was the most efficient, and thus subjected to the five-dose screen where it showed excellent broad activity against almost all tested cancer subpanels. Furthermore, all conjugates (5a–e and 7a–i) showed a good anti-proliferative activity towards colorectal cancer SW-620 and HT-29 cell lines, with an excellent inhibitory effect for compounds 5a and 5d (IC50 = 8.7 and 9.4 µM (5a), and 6.5 and 9.8 µM for (5d), respectively). Both compounds displayed selective cytotoxicity with good safety profile. In addition, both compounds provoked apoptosis in a dose dependent manner in SW-620 cells. Also, they significantly inhibited the anti-apoptotic Bcl2 protein expression and increased the cleaved PARP level that resulted in SW-620 cells apoptosis. 相似文献