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691.
Inflammatory conditions of the gastrointestinal tract and iron-deficiency anemia are very common in humans. Acute intestinal inflammation was pathologically established in rats by intraluminal administration of acetic acid into the duodenum and the proximal jejunum. The study included two control groups of intact (untreated) rats and sham-operated (saline-treated) rats for each intestinal segment. A third group of rats received acetic acid. The acetic acid-induced inflammatory process was established histopathologically and biochemically. Two days after treatment, iron absorption was measured using ligated 10-cm loops of proximal jejunum or ligated duodenum in which 59Fe was injected intraluminally (n=6 in each group). In another four control groups (intact and sham-operated for each intestinal segment) and two acetic acid-treated groups, serosal-luminal secretion of 59Fe was measured after intravenous injection (n=5 in each group). 59Fe transfer from the lumens of the duodenum and jejunum to the portal system was significantly lower in those rats in whom inflammation was induced by acetic acid. There was no apparent serosal-luminal secretion of intravenously injected 59Fe in any of the studied groups. We conclude that acetic acid-induced intestinal inflammation significantly reduces iron absorption by the duodenum and the proximal jejunum. 相似文献
692.
Mahmoud M. Hamed El-Dean Adel M. Kamal Abdel-Mohsen Shawkat A. Tolba Mahmoud S. 《Russian Journal of Bioorganic Chemistry》2021,47(1):208-220
Russian Journal of Bioorganic Chemistry - Diclofenac is considered one of the best drugs used as anti-inflammatory agent, so in the present work new diclofenac derivatives containing bioactive... 相似文献
693.
Adel Garas Elizabeth Webb Vinochani Pillay Donald MacPhee William Denny Hilary Zeller Richard Cotton 《Mutation Research - Genetic Toxicology and Environmental Mutagenesis》2009,678(1):20-29
We report the development of a simple, cost-effective assay for detecting compounds that have the ability to interact with and modify DNA. Potential uses for the assay lie in the areas of early genotoxicity testing of drug candidates, anticancer and antibiotic drug discovery, environmental monitoring and testing in the food, beverage and cosmetics industries. At present the assay has been used to assess direct-acting compounds only and it is yet to be established whether the assay is compatible with bio-activation. The methodology is based on the oxidative reaction of potassium permanganate with pyrimidine bases, which have become perturbed and more reactive by the agent under test. Results are recorded by use of UV/vis spectroscopy. The adaptation to a multi-well plate format provides the capacity for high throughput utilizing small amounts of compounds. Over 100 compounds, comprising different classes of DNA-binding chemicals as well as non-binding controls, have been put through the assay and the results compared with existing genotoxicity testing data from other methods. The assay has shown to be predictive of the results of other genotoxicity testing methods. We have found that the method is overall predictive of 71% of Ames bacterial reverse-mutation test results (where data are given) encompassing both negative and positive results. 相似文献
694.
Elshafei Adel A. El-Orabey Waled M. Fathallah Fathallah B. Esmail Ramadan M. Abou-Zeid Mohamed A. 《Molecular biology reports》2022,49(3):1903-1915
Molecular Biology Reports - Thirteen Egyptian wheat cultivars were evaluated and characterized for adult plant resistance to yellow, leaf, and stem rusts. SSR markers linked to yellow, leaf and... 相似文献
695.
696.
Donia D. McLemore Adel El Naggar L. Clifton Stephens John H. Jardine 《Biotechnic & histochemistry》1990,65(6):279-291
Flow Cytometric (FCM) DNA content analysis of paraffin-embedded tissues has become a widely accepted procedure in assessing the biologic course in some tumors from archival material. Difficulty in interpreting histograms is frequently due to high levels of debris, and wide coefficients of variation (CV). These may lead to underestimating near-diploid abnormality. Although the clinical significance of low-degree aneuploidy has yet to be established, the procedure reported here improved our endeavor to detect DNA Indices (DI) of at least 1.1%. Experience has shown that careful technique can result in overall improvement of DNA histograms by lowering levels of debris and % CV, dramatically so in some cases. Archival histograms can be generated that rival in quality fresh tissue results. Archival material is currently employed for diagnostic and research purposes. 相似文献
697.
698.
Najla Adel Saleh Michele Patrícia Rode Jelver Alexander Sierra Adny Henrique Silva Juliano Andreoli Miyake Fabíola Branco Filippin-Monteiro Tnia Beatriz Creczynski-Pasa 《Cytotechnology》2021,73(1):35
AbstractThe development of new treatments for malignant melanoma, which has the worst prognosis among skin neoplasms, remains a challenge. The tumor microenvironment aids tumor cells to grow and resist to chemotherapeutic treatment. One way to mimic and study the tumor microenvironment is by using three-dimensional (3D) co-culture models (spheroids). In this study, a melanoma heterospheroid model composed of cancer cells, fibroblasts, and macrophages was produced by liquid-overlay technique using the agarose gel. The size, growth, viability, morphology, cancer stem-like cells population and inflammatory profile of tumor heterospheroids and monospheroids were analyzed to evaluate the influence of stromal cells on these parameters. Furthermore, dacarbazine cytotoxicity was evaluated using spheroids and two-dimensional (2D) melanoma model. After finishing the experiments, it was observed the M2 macrophages induced an anti-inflammatory microenvironment in heterospheroids; fibroblasts cells support the formation of the extracellular matrix, and a higher percentage of melanoma CD271 was observed in this model. Additionally, melanoma spheroids responded differently to the dacarbazine than the 2D melanoma culture as a result of their cellular heterogeneity and 3D structure. The 3D model was shown to be a fast and reliable tool for drug screening, which can mimic the in vivo tumor microenvironment regarding interactions and complexity.Graphic abstract 相似文献
699.
Karima Salem Fatma Elgharbi Hajer Ben Hlima Massimiliano Perduca Adel Sayari Aïda Hmida-Sayari 《Biotechnology progress》2020,36(4):e2964
An extracellular amylase (AmyKS) produced by a newly isolated Bacillus subtilis strain US572 was purified and characterized. AmyKS showed maximal activity at pH 6 and 60°C with a half-life of 10 min at 70°C. It is a Ca2+ independent enzyme and able to hydrolyze soluble starch into oligosaccharides consisting mainly of maltose and maltotriose. When compared to the studied α-amylases, AmyKS presents a high affinity toward soluble starch with a Km value of 0.252 mg ml−1. Coupled with the size-exclusion chromatography data, MALDI–TOF/MS analysis indicated that the purified amylase is a dimer with a molecular mass of 136,938.18 Da. It is an unusual feature of a non-maltogenic α-amylase. A 3D model and a dimeric model of AmyKS were generated showing the presence of an additional domain suspected to be involved in the dimerization process. This dimer arrangement could explain the high substrate affinity and catalytic efficiency of this enzyme. 相似文献
700.
The reliability of morphological parameters of Alnus fruticosa s. l. on the territory of Asian Russia was studied. It has been revealed that the species has a complex internal structure
stipulated by the climatic and forest-growing conditions in different parts of the range. The results of phenotypic variability
and sequences of internal transcribed spacer ITS1 of nuclear ribosomal DNA of the taxa of the subgenus Alnobetula indicate the species rank of Alnus viridis and subspecies rank of A. fruticosa, A. sinuata, and A. crispa with the priority species name A. crispa. A. maximowiczii, A. glutipes, A. kamtschatica, and A. mandshurica are the result of intraspecific variability of the polymorphic species A. fruticosa. 相似文献