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891.
Lahbib Aida Ghodbane Soumaya Elferchichi Myriam Sakly Mohsen Abdelmelek Hafedh 《Biological trace element research》2014,160(1):67-72
The interaction of static magnetic fields (SMFs) with living organisms is a rapidly growing field of investigation. The magnetic fields (MFs) effect observed with radical pair recombination is one of the well-known mechanisms by which MFs interact with biological systems. SMF influenced cellular antioxidant defense mechanisms by affecting antioxidant enzymes such as superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT). However, there were insufficient reports about the effects of SMF on macro and trace elements in serum, and the results were contradictory until now. In the current study, 12 rats were divided into two groups, namely as control and exposure group (128 mT and 1 h/day during five consecutive days). The macro and trace element concentrations in serum were examined. No significant difference was observed in the sodium (Na), potassium (K), calcium (Ca), phosphorus (P), and selenium (Se) levels in rat compared to control. By contrast, exposure to SMF showed an increase in the zinc (Zn) level and a decrease in iron (Fe) concentration. Under our experimental conditions, SMF exposure cannot affect the plasma levels of macroelements, while it can disrupt Zn and Fe concentrations in rat. 相似文献
892.
Quinone-containing carcinostatics, aclacinomycin A and its derivatives were investigated on the convertibility to free radical under a mild reducing condition. The hyperfine structures of electron spin resonance (ESR) spectra were satisfactorily reproduced by computer simulations, using the hyperfine coupling constants calculated by the Intermediate Neglect of Differential Overlap Molecular Orbital (INDO MO) method. This verifies the reliability of molecular orbital calculations and opens a way to analyze theoretically the correlation between chemical structures and carcinostatic activities. By analyzing hyperfine structures of ESR spectra, the free radical produced from aclacinomycin was identified as a neutral form of semiquinone radical of intact aclacinomycin. Taking into account the previous finding that 7-deoxyaklavinone (C1) is formed reductively by cytochrome P-450 reductase (EC 1.6.2.4; Komiyama et al., 1979), it is postulated that two types of semi-quinone radicals exist in vivo. 相似文献
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895.
Ghofrane Lahmadi Aida Lahmar Mansour Znati Mohamed Tahar Elaieb Mohamed Larbi Khouja Roberta Ascrizzi Guido Flamini Abdel Halim Harrath Leila Chekir-Ghedira Hichem Ben Jannet 《化学与生物多样性》2021,18(11):e2100315
In recent years, there has been a growing interest in the screening of natural active ingredients from Eucalyptus essential oils because of their evident importance in practical utility and their undeniable therapeutic properties. Based on this, the aim of the present study was to investigate the chemical profile of the essential oils of the trunk bark of Eucalyptus torquata Luehm. (ETEO), and E. salmonophloia F. Muell. (ESEO), growing in Tunisia. The in vitro cytotoxic properties of the extracted EOs were also evaluated against two human cancer cell lines: breast carcinoma cell lines MDA-MB-231 and colorectal cancer cell lines SW620. The analysis by gas chromatography coupled with mass spectrometry (GC/MS) led to the identification of 32 compounds from the ETEO, with the dominant constituents being the monoterpenes trans-myrtanol (73.4 %) and myrtenol (4.7 %), and the apocarotene (E)-β-ionone (3.9 %). In the case of ESEO, 29 compounds were identified with trans-myrtanol (25.0 %), decanoic acid (22.1 %), nonanoic acid (9.8 %), γ-elemene (6.5 %), γ-maaliene (5.5 %), and α-terpineol (5.3 %) as the main components. The cytotoxicity of EOs against the two chosen cell lines was tested using Crystal Violet Staining (CVS) assay and 5-fluorouracil as a reference drug. The two EOs exhibited a significant dose-dependent inhibition against the viability of the used cell lines. Their inhibitory effects were particularly observed towards SW620 colon carcinoma cells with IC50 values of 26.71±1.22 and 22.21±0.85 μg/mL, respectively, indicating that both oils were more cytotoxic for SW620 cells compared to MDA-MB-231 one. 相似文献
896.
Tissues contain distinct stem cell niches, but whether cell turnover is coordinated between niches during growth is unknown. Here, we report that in mouse skin, hair growth is accompanied by sebaceous gland and interfollicular epidermis expansion. During hair growth, cells in the bulge and outer root sheath temporarily upregulate the glutamate transporter SLC1A3, and the number of SLC1A3+ basal cells in interfollicular epidermis and sebaceous gland increases. Fate mapping of SLC1A3+ cells in mice revealed transient expression in proliferating stem/progenitor cells in all three niches. Deletion of slc1a3 delays hair follicle anagen entry, uncouples interfollicular epidermis and sebaceous gland expansion from the hair cycle, and leads to reduced fur density in aged mice, indicating a role of SLC1A3 in stem/progenitor cell activation. Modulation of metabotropic glutamate receptor 5 activity mimics the effects of SLC1A3 deletion or inhibition. These data reveal that stem/progenitor cell activation is synchronized over distinct niches during growth and identify SLC1A3 as a general marker and effector of activated epithelial stem/progenitor cells throughout the skin. 相似文献
897.
Herminia I. Perez Hector Luna Luis A. Maldonado Horacio Sandoval Norberto Manjarrez Aida Solis Remedios Sanchez 《Biotechnology letters》1998,20(1):77-79
Whole cells of Nocardia corallina B-276, oxidized 21 substituted benzyl alcohols, at 1 mM scale, to carboxylic acids at 28-30°C, giving yields of products from 5 to 77%. 相似文献