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排序方式: 共有8804条查询结果,搜索用时 15 毫秒
31.
The objective of the study was to determine the relationship between serum concentrations of selenium (SeS) and zinc (ZnS), total antioxidant status (TAS) and endothelial function assessed by ultrasonographic method of dilatation of the brachial artery in 141 hypertensive patients.Patients with SeS < median were characterized by a statistically significantly lower flow-mediated dilation (FMD) than patients with SeS ≥ median. Patients with TAS < median were characterized by a significantly lower FMD than patients with TAS ≥ median. Older age, higher BMI, male gender, higher blood total cholesterol, ischemic heart disease, smoking and lower SeS constitute independent predictors of inferior endothelial function, expressed in lower FMD values. Smoking is an independent predictor of lower TAS, and the use of β-blockers and higher serum selenium levels are independent predictors of higher TAS.In summary, a decrease in TAS should be considered as a mechanism of inferior endothelial function in hypertensive patients conditioned by a decrease in SeS. 相似文献
32.
《Journal of Pharmaceutical Analysis》2019,9(3):193-200
Pinus densiflora needle extract (PDNE) is widely reported to have many pharmacological activities including antioxidant potential. However, the solvent system used for extraction greatly affects its antioxidant quality. Hence, in the present study, we investigated the effect of a different ratio (vol/vol) of ethanol to water (0–100%) in the extraction of PDNE with potent antioxidant capacity. The chemical assays, 2,2-diphenyl-1 picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), were conducted to assess the antioxidant potential of PDNE. Subsequently, the cytoprotective effect of PDNE was determined using tert-butyl hydroperoxide (TBHP)-challenged HepG2 cellular model. The needle extracts from 40% ethanol (PDNE-40) showed greater radical scavenging activity followed by 60%, 20%, 80%, 0% and 100% ethanol extracts. EC50 value of the most active extract, PDNE-40, was 8.56 ± 0.51 μg/mL, relative to 1.34 ± 0.28 μg/mL of the standard trolox (for ABTS radical), and 75.96 ± 11.60 μg/mL, relative to 4.83 ± 0.26 μg/mL of the standard trolox (for DPPH radical). Either PDNE-20 or PDNE-40 pretreatment remarkably decreased the levels of reactive oxygen species (ROS), lipid peroxides and protein carbonyls in TBHP-challenged HepG2 cells. In addition, both PDNE-20 and PDNE-40 significantly reversed the decreased ratio of reduced (GSH) to oxidized (GSSG) glutathione. Moreover, these two extracts showed a significant inhibitory effect on TBHP-induced nuclear damage and loss of cell viability. In summary, the inclusion of 40% ethanol in water for extraction of Pinus densiflora needle greatly increases the antioxidant quality of the extract. 相似文献
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ObjectiveTo investigate the clinical characteristics and prognoses of patients with postpartum acute kidney injury (PPAKI).MethodsWe retrospectively reviewed the clinical presentations, laboratory examinations, treatments, and outcomes of patients with PPAKI admitted to our hospital from January 2013 to December 2017. We then analyzed the clinical characteristics and prognoses of the mothers and their infants.ResultsOf 37 patients diagnosed with PPAKI, 26 (70.3%) received treatment in the intensive care unit, mainly for hemolysis, elevated liver enzymes, low platelet count (HELLP) syndrome (28/37, 75.7%), pre-eclampsia (26/37, 70.3%), and postpartum hemorrhage (22/37, 59.5%). Twenty patients required renal replacement treatment (RRT), but renal recovery times were similar in the RRT and non-RRT groups. Renal function recovered completely in 30 patients (81.1%) and partially in one patient (2.7%), and was not re-examined in two patients (5.4%). Three patients (8.1%) were lost to follow-up. Only one patient (2.7%) remained dialysis-dependent, and no maternal deaths occurred. The preterm birth, low birth weight, and infant survival rates were 70.7% (29/41), 68.3% (28/41), and 78.0% (32/41), respectively.ConclusionRRT does not reduce renal recovery time compared with non-RRT. Overall, the prognoses of both mothers and their fetuses are good following treatment for PPAKI. 相似文献
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Fusarium is an important plant pathogen and many cell wall-degrading enzymes (CWDEs) are produced in Fusarium-infected plant tissues. To investigate the role of CWDEs in the pathogenicity of pitaya pathogen, we isolated a Fusarium equiseti strain from the diseased pitaya fruit and the activities of CWDEs were determined. The higher polygalacturonase (PG) activity was confirmed both in vitro and vivo. Aiming at the PG gene, the CRISPR/Cas9 system of F. equiseti was constructed and optimized for the first time. Through the process of microhomology-mediated end joining, the flanking region containing 30 bp was used to mediate the homologous recombination of Cas9 double-strand breaks, and the PG gene knockout mutants were obtained by protoplast transformation. Through the phenotypic and pathogenicity experiments of the wild-type strain and mutant strain, the results showed that the colony growth rate and spore production of the strain without the PG gene decreased to some extent, and the lesion diameter and the degree of pericarp cell damage decreased, which showed that the CRISPR/Cas9 system could be used in F. equiseti and PG enzyme and can play a significant role in the interaction between F. equiseti and pitaya fruit. 相似文献
37.
Reactive oxygen species (ROS) play a significant role in human cells. Excessive ROS production damages important macromolecules such as nucleic acids and can initiate and develop the carcinogenesis process. Antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx), and xanthine oxidoreductase (XOR) are responsible for maintaining the balance between the functions of free radical formation and eliminating their excessive amounts.Based on the analyzed literature, the following conclusions can be made:1. Antioxidant enzymes activity are important for diagnosing neoplastic diseases such as non-small-cell lung cancer, bladder cancer, ovarian cancer, and colon cancer.2. Non-small-cell lung cancer is usually characterized by decreased SOD and CAT activity and increased glutathione GST activity. Lowered SOD, CAT, and GPx activity is characteristic of bladder cancer. XOR, CAT, SOD and GPx expression is decreased in patients with ovarian cancer. Colorectal cancer is characterized by increased MnSOD expression (in vitro studies) and SOD expression while CAT, GPx, and GR are decreased (in vivo study).3. SOD, CAT, and XOR are promising prognostic markers in cancer of the lung, bladder, ovarian, and colon. 相似文献
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Gagandeep Manchanda Rupinder Kaur Sodhi Upendra Kumar Jain Ramesh Chandra 《Journal of microencapsulation》2018,35(1):49-61
Objectives: Curcumin (Cur) exhibits weak microbicidal activity owing to high lipophilicity and low cell permeability. Therefore, in the present investigation, Cur was iodinated using elemental iodine (I2) to synthesise Cur–I2 powder that was later formulated as Cur–I2 dermal cream and characterised in vitro for antimicrobial and antioxidant activities.Methods and results: Electrophilic addition of I2 saturated the olefinic bonds of Cur, as confirmed by UV/visible spectroscopy, FT-IR, 1H NMR and DSC techniques. In addition, in vitro skin permeation and retention analysis indicated that Cur–I2 cream followed the first order and Higuchi model for drug release through the rat skin. The minimum inhibitory concentration (MIC) of Cur–I2 powder was measured to be 60 and 90?µg/ml significantly (p?0.05) lower than 150 and 120?µg/ml of Cur against Staphylococcus aureus and Escherichia coli, respectively. Moreover, Cur–I2 also exhibited strong antioxidant potential.Conclusions: Cur–I2 cream warrants further in vivo study to scale up the technology for clinical translation. 相似文献
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