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71.
Simple high‐performance liquid chromatography method for formaldehyde determination in human tissue through derivatization with 2,4‐dinitrophenylhydrazine 下载免费PDF全文
Bilal Yilmaz Ali Asci Kaan Kucukoglu Mevlut Albayrak 《Journal of separation science》2016,39(15):2963-2969
A simple high‐performance liquid chromatography method has been developed for the determination of formaldehyde in human tissue. FA Formaldehyde was derivatized with 2,4‐dinitrophenylhydrazine. It was extracted from human tissue with ethyl acetate by liquid–liquid extraction and analyzed by high‐performance liquid chromatography. The calibration curve was linear in the concentration range of 5.0–200 μg/mL. Intra‐ and interday precision values for formaldehyde in tissue were <6.9%, and accuracy (relative error) was better than 6.5%. The extraction recoveries of formaldehyde from human tissue were between 88 and 98%. The limits of detection and quantification of formaldehyde were 1.5 and 5.0 μg/mL, respectively. Also, this assay was applied to liver samples taken from a biopsy material. 相似文献
72.
Despite CYP induction in vitro in precision-cut liver slices (LS) is well documented, there are no standardised assays for
determining CYP activity as a major end-point. In this paper, short-term assays with intact and homogenised LS from male and
female rats were directly compared. We obtained similar results for 7-ethoxycoumarine O-deethylation (ECOD) with LS from both
sexes: higher basal activities were measured in LS homogenate, whereas slightly stronger induction by BNF was found with intact
LS. CYP3A-dependent basal and dexamethasone (Dex)-induced 2β-, 15β- and 6β-testosterone hydroxylation (TH) rates were higher
in both intact and homogenised LS from male compared to female rats. CYP3A induction in vitro could likewise be detected in
intact and homogenised LS preferentially by determining 2β- and 15β-TH, with higher induction factors observed in LS from
females. 6β-TH seems to be less inducible in intact LS of males. In vivo pretreatment of liver donors with BNF and Dex did
not substantially disturb the subsequent in vitro induction of ECOD and TH, respectively. 相似文献
73.
Olthof AW Sijens PE Kreeftenberg HG Kappert P Irwan R van der Jagt EJ Oudkerk M 《Magnetic resonance imaging》2007,25(2):228-231
Liver iron concentration was determined in 28 patients by magnetic resonance imaging using the method of Gandon et al. (Non-invasive assessment of hepatic iron stores by MRI. Lancet 2004;363:357-362). The result showed a significant correlation with blood plasma ferritin content (Spearman's r=.66; P<.001) and a slightly improving correlation coefficient when limited to those patients not known to have inflammation (r=.82; n=17; P<.001). Zooming in on patients with hematologic disease also had a beneficial effect on the correlation between liver iron content and plasma ferritin level (r=.79; n=13; P=.001). It is concluded that in patients without inflammation and in patients with hematologic disease, the content of ferritin in blood is a better predictor of liver iron content than in other patient categories. 相似文献
74.
Determination of sulfonamides in livers using matrix solid-phase dispersion extraction high-performance liquid chromatography 总被引:1,自引:0,他引:1
Zhang Y Xu X Qi X Gao W Sun S Li X Jiang C Yu A Zhang H Yu Y 《Journal of separation science》2012,35(1):45-52
The matrix solid-phase dispersion (MSPD) was applied for extracting seven sulfonamides (SAs) in liver samples. The separation and determination were carried out by high-performance liquid chromatography. The analytes were derivated with fluorescamine and detected with fluorescence detector. The types of dispersion adsorbents for MSPD were examined and the highest recovery was obtained when the diatomaceous earth was used as the dispersion adsorbent and the mass ratio of dispersion adsorbent to sample was 3:1. The acetone was used as the elution solvent. Under the optimal conditions, the linear range for determining the SAs in liver samples was 5.0-1000.0 ng/g. The porcine, chicken and cattle liver samples were analyzed and the average recoveries of seven SAs were higher than 84.6%. 相似文献
75.
《Arabian Journal of Chemistry》2022,15(7):103950
The ATP-binding cassette is the major class of transporters responsible for the efflux of chemotherapeutic agents from cancer cells, resulting in treatment failures of cancer’s patients. Suaeda vermiculata Forssk. ex. J. F. Gmel. is traditionally known for its liver protective activity. The LC-MS based chemical profilings of the sequentially partitioned sub-extracts obtained from the alcoholic extract of S. vermiculata using n-hexane, chloroform, ethyl acetate, and n-butanol as fractionating solvents, identified a total of thirty six compounds. These sub-extracts were evaluated for their anti-hepatocarcinoma activity against the sensitive HepG2 and doxorubicin (DOX)-resistant, HepG-2/ADR cell lines. A mixture of doxorubicin and sub-extracts at 20 μg/ml doses were also tested for their anti-hepatocarcinoma activity. The exhibited IC50 values for the chloroform, ethyl acetate, n-hexane, and n-butanol sub-extracts, and the doxorubicin against HepG2, and HepG-2/ADR cell lines were found at 64.5, 66.8, 81.25, 125, 1.3 μg/ml, and 110.1, 91.82, 138.2, 265.7, 4.77 μg/ml levels, respectively. However, the treatment of resistant cells with 20 μg/ml of different sub-extracts in combination with the doxorubicin showed significant improvements in the doxorubicin activity against the resistant cells, and the IC50 values for DOX + chloroform, DOX + ethyl acetate, DOX + n-hexane, and DOX + n-butanol against resistant cells, were at 1.77, 2.05, 2.66, and 2.71 μg/ml levels, respectively. The IC50 values exhibited 2.69x, 2.33x, 1.79x and 1.76x-folds reversal of the sensitivity in the resistant cancer cell lines. The molecular docking studies of the compounds identified in the LC-MS chemical profilings, against three ATP-binding cassette proteins i.e., ABCB1, ABCC1, and ABCG2, showed that flavonoids as the major class of compounds responsible for reversal of the resistant cells sensitivities. The predicted binding affinity for the flavonoids against the above mentioned three ATP-binding cassette proteins’ are in the ranges of ~?8 to ?11 kcal/mol. Our results clearly indicate that the presence of flavonoids, as the major class of compounds in the S. vermiculata is responsible for the chemosensitization of the resistant HCC-cell lines. Moreover, the structures, 21 (5‐O‐methyl visamminol), 22 (N-trans-feruloyl tyramine), 27 (atractylenolide-III), and 32 (ginsenoside-Rh2) were also identified among the potential ATP-binding cassette’s modulators during the current study. These observations put the S. vermiculata in perspective with the traditionally claimed liver protective efficacy of the plant. 相似文献
76.
77.
Staining of tissue is a significant process in histotechnology and staining techniques are used in the examination and diagnosis of diseases. The increase of international awareness for the environment, ecology, and health directed people to reduce toxic effluents and stop usage of dangerous chemical dyes. The present trend throughout the world is shifting towards to use of natural products over their synthetic alternatives. Therefore, in this study, the dyeing ability of alkanet plant on the cells of unstained sections taken from Wistar rat liver was investigated. The extract of Alkanna tinctoria contain naphthaquinone group of dyestuff. Chemical characterization of A. tinctoria extract was performed with HPLC-TOF/MS and UV spectra analysis, respectively. Different metal salts were used in the staining processes in order to obtain different colors. In the staining of without adding mordant (metal salt) to the extract, pale brown staining was obtained in the cytoplasm. Light pink color was obtained with the addition of CuSO4 mordant. Dark pink-red color was achieved by adding alum, and also NiSO4 was added for light purple staining. The staining of cytoplasm of different cells in liver tissue was achieved successfully with the extract of A. tinctoria and different colors were obtained using various mordants. 相似文献
78.
AimThe purpose of the study is to research the effect of quercetin, which has a good antioxidant characteristic in rats exposed to sodium fluoride (NaF) toxication, on oxidant and antioxidant activity in liver tissue and erythrocyte.Material and method40 Swiss albino male rats with a weight of approximately 20–25 gr were used in the study. The rats were separated into 4 equal groups (n = 10). The first group, the control group, was given normal drinking water; the second group was given 12 mg/kg/day NaF; the third group was given 40 mg/kg/day quercetin; the fourth group was given 12 mg/kg/day NaF+40 mg/kg/day quercetin orally for 30 days. As a result of the experiment, plasma AST and ALT activities were found. Total oxidant capacity (TOC) and total antioxidant capacity (TAC) analyses were made in liver tissue and erythrocyte hemogenisate. Histopathological analyses of the liver tissue were conducted.ResultsNo changes were found in plasma ALT activities between groups. Increases were found in AST activity of all groups. While erythrocyte TAC level was found to increase in fluorine and fluorine + quercetin group when compared with the control group, erythrocyte TOC level was found to increase in all groups when compared with the control group. No significant change was found in TOC and TAC levels in the liver tissue. In liver tissue histopathology, while hydropic degeneration and cellular necrosis were found in vena centralis area in fluorine group, hydropic degeneration was found in heptocytes in centrilobular area in the quercetin group. In the fourth group, hydropic degeneration and centrilobular necrosis were more severe. It was found that in rats which are given NaF experimentally, fluorine and quercetin caused histopathological degenerations in the liver tissue during this time.ConclusionWhile no changes were found in TOC and TAC levels of liver tissue, antioxidant capacity was found to be stimulated in fluorine groups in erythrocyte. 相似文献
79.
Purpose
To evaluate the liver-to-muscle signal intensity and R2* methods to gain a transferable, clinical application for liver iron measurement.Materials and Methods
Sixteen liver phantoms and 33 human subjects were examined using three 1.5-T MRI scanners from two different vendors. Phantom-to-muscle and liver-to-muscle signal intensity ratios were analyzed to determine MRI estimated phantom and hepatic iron concentration (M-PIC and M-HIC, respectively). R2* was calculated for the phantoms and the liver of human subjects. Seven patients' biochemical hepatic iron concentration was obtained.Results
M-PIC and R2* results of three scanners correlated linearly to phantom iron concentrations (r=0.984 to 0.989 and r=0.972 to 0.981, respectively), and no significant difference between the scanners was found (P=.482 and P=.846, respectively) in vitro. The patients' R2* correlated linearly to M-HIC of the standard scanner (r=0.981). M-HIC values did not differ from those obtained from the biopsy specimens (P=.230). The difference in M-HIC was significant, but the difference in R2* was not significant between the scanners (P<.0001 and P=.505, respectively) in vivo.Conclusion
Both methods, M-HIC and R2*, are reliable iron concentration indicators with linear dependence on iron concentration in vivo and in vitro. The R2* method was found to be comparable among different scanners. Transferability testing is needed for the use of the methods at various scanners. 相似文献80.