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Thymoquinone (TQ) is a major constituent of Nigella sativa oil with reported anti-oxidative activity and anti-inflammatory activity in animal cells. It also inhibits proliferation and induces programmed cell death (apoptosis) in human skin cancer cells. The present study sought to detect the influence of TQ on dividing cells of three plant systems and on expression of Bcl2-associated athanogene-like (BAG-like) genes that might be involved during the process of cell death. BAG genes are known for the regulation of diverse physiological processes in animals, including apoptosis, tumorigenesis, stress responses, and cell division. Synthetic TQ at 0.1 mg/mL greatly reduced wheat seed germination rate, whereas 0.2 mg/mL completely inhibited germination. An Evans blue assay revealed moderate cell death in the meristematic zone of Glycine max roots after 1 h of TQ treatment (0.2 mg/mL), with severe cell death occurring in this zone after 2 h of treatment. Light microscopy of TQ-treated (0.2 mg/mL) onion hairy root tips for 1 h revealed anti-mitotic activity and also cell death-associated changes, including nuclear membrane disruption and nuclear fragmentation. Transmission electron microscopy of TQ-treated cells (0.2 mg/mL) for 1 h revealed shrinkage of the plasma membrane, leakage of cell lysate, degradation of cell walls, enlargement of vacuoles and condensation of nuclei. Expression of one BAG-like gene, previously associated with cell death, was induced 20 min after TQ treatment in Glycine max root tip cells. Thus, TQ has multiple effects, including cell death, on dividing plant cells and plants may serve as a useful system to further investigate the mechanisms underlying the response of eukaryotic cells to TQ.  相似文献   
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Cisplatin (CP) is a cornerstone chemotherapeutic agent, however, its neurotoxicity is a chief cause of its limited usage. Linagliptin, which is a dipeptidyl peptidase‐4 enzyme inhibitor, has exhibited considerable neuroprotective potential. We aimed to evaluate the linagliptin modulatory effects on endoplasmic reticulum (ER) stress, redox status, and apoptosis in CP‐induced neurotoxicity. Thirty mice were allocated equally into the control group, Group II: CP group, and Group III: linagliptin treated CP group. All groups were subjected to the measurement of hippocampal messenger RNA gene expression of glucose‐regulated protein‐78 and C/EBP homologous protein (CHOP). Peroxisome proliferator‐activated receptor γ coactivator 1α and cleaved caspase‐3 levels were assessed by the enzyme‐linked immunosorbent assay technique while malondialdehyde, reduced glutathione levels and superoxide dismutase activity were detected spectrophotometrically. Linagliptin ameliorated ER stress and enhanced antioxidant status with cognitive function improvement. Linagliptin may be considered a promising neuroprotective agent owing to its ability to reduce ER/oxidative stress.  相似文献   
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Lipoprotein lipase (LPL) and Apolipoprotein C-III (APOC-III) play an important role in lipid metabolism. The aim of this study was to explore the possible associations of the gene polymorphisms (LPL HindIII, LPL Ser(447)-Ter and APOC3 SstI), diabetes mellitus, and plasma lipids with myocardial infarction. The polymorphisms were assessed by restriction assay in 200 Egyptian MI patients (100 diabetic and 100 non-diabetic) and 100 healthy controls. This study demonstrated that individuals with the H2H2 genotype or S2 allele have more than three times higher relative risk of suffering from MI than those carrying the H1H1 or S1S1. Type 2 DM mainly lowers HDL-C levels in MI patients who carry H2H2 or S2S2 genotype and increases TC, TG, and LDL levels in MI patients carrying H2H2 or S2S2 genotype compared with non-diabetic MI patients carrying the same genotypes. In S447X polymorphism, it was observed that DM led to loss of the protective lipid profile in MI patients carrying 447XX genotype. These findings suggest that H2H2 or S2S2 genotypes are associated with dyslipidemia and increased risk of myocardial infarction. The S447X polymorphism is associated with a favorable lipid profile. However, the association of diabetes mellitus with these polymorphisms leads to unfavorable lipid profile.  相似文献   
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A proteomic approach has enabled the identification of an orthologue of the splicing factor hnRNP G in the amphibians Xenopus tropicalis, Ambystoma mexicanum, Notophthalmus viridescens and Pleurodeles walt, which shows a specific RNA-binding affinity similar to that of the human hnRN G protein. Three isoforms of this protein with a differential binding affinity for a specific RNA probe were identified in the P. walt oocyte. In situ hybridization to lampbrush chromosomes of P. waltl revealed the presence of a family of hnRNP G genes, which were mapped on the Z and W chromosomes and one autosome. This indicates that the isoforms identified in this study are possibly encoded by a gene family linked to the evolution of sex chromosomes similarly to the hnRNP G/RBMX gene family in mammals.  相似文献   
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In the present study, it was hypothesized that micromorphology of the surface of many lizard scales appears to mimic the topography of the habitat in which they live. Many authors have suggested that the microstructure of the superficial surface of scales have undergone important adaptations and have functional value in lizards. In this study, we investigated the variation and adaptation of the micromorphology and microstructure of the superficial surface of the dorsal and ventral scales from the mid-body region of Stellagama stellio (Agamidae), Stenodactylus petrii (Gekkonidae), Acanthodactylus boskianus (Lacertidae), Eumeces schneideri (Scincidae), Trachylepis quinquetaeniata (Scincidae), Scincus scincus (Scincidae), Varanus griseus (Varanidae), Chameleo chameleon (Chamaeleonidae). Skin specimens were prepared and analyzed using scanning electron microscopy. The dorsal and ventral scale surfaces had microstructure in the studied species and they exhibited unique patterns that somewhat resembled the topography of the microhabitats in which they lived. Similarity was detected in the three most related species, those having a common family, Scincidae. Ecomorphological relationships were detected between the dorsal and ventral scale microstructures and microhabitats. We conclude that environmental factors have observable influences on the microstructure of lizard scales.  相似文献   
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Genetic diversity and phylogenetic analyses of 24 species, representing nine sections of the genus Galium (Rubiaceae), have been made using the Inter Simple Sequence Repeats (ISSR), Randomly Amplified Polymorphic DNA (RAPD), and combined ISSR and RAPD markers. Four ISSR primers and three RAPD primers generated 250 polymorphic amplified fragments. The results of this study showed that the level of genetic variation in Galium is relatively high. RAPD markers revealed a higher level of polymorphism (158 bands) than ISSR (92 bands). Clustering of genotypes within groups was not similar when RAPD and ISSR derived dendrograms were compared. Six clades can be recognized within Galium, which mostly corroborate, but also partly contradict, traditional groupings. UPGMA-based dendrogram showed a close relationship between members of section Leiogalium with G. verum and G. humifusum (sect. Galium), and G. angustifolium (sect. Lophogalium). Principal coordinated analysis, however, showed some minor differences with UPGMA-based dendrograms. The more apomorphic groups of Galium form the section Leiogalium clade including the perennial sections Galium, Lophogalium, Jubogalium, Hylaea and Leptogalium as well as the annual section Kolgyda. The remaining taxa of Galium are monophyletic.  相似文献   
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