Effects of Spironolactone on Hypoxia-Inducible Factor-1α in the Patients Receiving Coronary Artery Bypass Grafting.

ABSTRACT: We explored the protective effect of spironolactone on cardiac function in the patients undergoing coronary artery bypass grafting (CABG) by determining serum hypoxia-inducible factor-1α (HIF-1α) before and after CABG. We used the propensity score matching method retrospectively to select 174 patients undergoing CABG in our hospital from March 2018 to December 2019. Of the 174 patients, 87 patients taking spironolactone for more than 3 months before CABG were used as a test group and other 87 patients who were not taking spironolactone as a control group. In all patients, serum HIF-1α and troponin I levels were determined before as well as 24 hours and 7 days after CABG, serum N-terminal probrain natriuretic peptide (NT-proBNP) level was determined before as well as 12, 24, and 36 hours after CABG, and electrocardiographic monitoring was performed within 36 hours after CABG. The results indicated that there were no significant differences in the HIF-1α level between the test group and the control group before and 7 days after CABG, but the HIF-1α level was significantly lower in the test group than that in the control group 24 hours after CABG (P < 0.01). The 2 groups were not significantly different in the troponin I level at any time point. There was no significant difference in the serum NT-proBNP level between the test group and the control group before CABG, but NT-proBNP (BNP) levels were all significantly lower in the test group than those in the control group at postoperative 12, 24, and 36 hour time points (all P <0.05). The incidence of postoperative atrial fibrillation was also significantly lower in the test group than that in the control group (P = 0.035). Spironolactone protects cardiac function probably by improving myocardial hypoxia and inhibiting myocardial remodeling.

The EGFP/hERG fusion protein alter the electrophysiological properties of hERG channels in HEK293 cells.

EGFP (enhanced green fluorescent protein) tagged to either the N (amino)-terminus [EGFP/hERG (human ether-a-go-go-related gene)] or C (carboxyl)-terminus (hERG/EGFP) of hERG channel is used to study mutant channel protein trafficking for several years. However, it has been reported that the process can alter hERG channel properties. The aim of the study was to determine whether EGFP tagged to N-terminus of hERG channels would alter the cellular localizations and the electrophysiological properties of hERG channels compared with untagged hERG channels. The hERG channels tagged with or without EGFP were transiently expressed in HEK (human embryonic kidney) 293 cells using a lipofectamine method. HEK 293 cells expressing pCDNA3-hERG or pEGFP-hERG were double immunolabelled with anti-hERG and anti-calnexin (an ER marker protein) followed with FITC- and TRITC (tetramethylrhodamine ß-isothiocyanate)-labelled secondary antibodies, respectively. Confocal laser scanning microscope was used to observe the cellular localization of EGFP-tagged hERG channels and untagged hERG channels. Patch-clamp technique was used to record whole cell currents. We found that the EGFP/hERG fusion protein and untagged hERG channels were both expressed not only on the cell surface membrane but also in the cytoplasm of HEK293 cells. The EGFP/hERG appeared to influence the hERG channel gating properties, including reduction of the peak tail current density, more rapid inactivation process, faster recovery from inactivation and faster deactivation kinetics compared with untagged hERG channels. Our results suggest that the EGFP/hERG channel alter the electrophysiological properties of hERG channel, but it does not seem to alter the cellular location of hERG channels. Thus, EGFP tagging to N-terminus might be used for research of subcellular location of hERG channels but not for the channel electrophysiological properties.

[Study of DNA examination in trace sample by carrier method].

OBJECTIVE: To solve the problems of DNA testing in trace sample. METHODS: Applying original carrier method to detect known trace blood DNA and to compare it with the results obtained by high effective DNA extracting method of Chelex-100. RESULTS: The carrier method not only could obtain the right STR genotype in the trace blood sample, but also was twice as sensitive as the Chelex-100 method. CONCLUSION: The carrier method could improve the DNA detection in trace sample. It is easy to operate and is much more valuable in the forensic case analysis.

Cd-doped ZnO quantum dots-based immunoassay for the quantitative determination of bisphenol A.

Bisphenol A (BPA) is a ubiquitous environmental contaminant in food products and aquatic ecosystems. Its endocrine and developmental toxicity presents a serious concern to human health and an effective high-throughput method for its detection is desirable. In this paper, water-soluble quantum dots (QDs) have been conjugated covalently with BPA antibodies and the conjugate has been utilized in a competitive fluorescence-linked immunoassay (FLISA). Cd-doped ZnO QDs were functionalized with poly(amidoamine) (PAMAM) dendrimers, as evidenced by ultraviolet absorption spectrum and fluorescence emission spectra analyses, and this led to their successful transfer into aqueous solution. Biological mass spectrometry demonstrated that the bisphenol A antibodies were successfully coupled to the water-soluble QDs, and the structures of these conjugates kept intact. The FLISA method allowed for BPA determination in a linear working range of 20.8-330.3 ng mL(-1) with the limit of detection (LOD) of 13.1 ng mL(-1). The recoveries of BPA from water samples were from 85.92% to 109.62%. In conclusion, a rapid and sensitive FLISA was developed by utilizing novel QD coupling method and validated for use in aqueous samples.

A study of photoluminescence properties and performance improvement of Cd-doped ZnO quantum dots prepared by the sol-gel method.

In the present work, ZnO quantum dots (QDs) have been prepared by the sol-gel method, and the performance of the QDs has been improved. The effect of Cd concentration on the structural and luminescent properties of the QDs, as well as the effect of the mass ratio of trioctylphosphine oxide (TOPO)/octadecylamine (ODA), has been investigated. The ZnO and Cd-doped ZnO QDs have hexagonal wurtzite structures and are 3 to 6 nm in diameter. When the Cd content was increased, the QD particle size was reduced; this effect was confirmed in the corresponding ultraviolet-visible spectra. The fluorescence intensity was simultaneously enhanced significantly. Both the UV and fluorescence spectra were blue-shifted. The luminous intensity was further enhanced when the QDs were modified with TOPO/ODA. Fourier transform infrared and X-ray diffraction techniques proved that the polymer successfully coated the surfaces of the QDs. A TOPO/ODA mass ratio of 1:2 was determined to result in the best optical performance among the different ratios examined. The results showed that the described synthetic method is appropriate for the preparation of doped QDs with high-fluorescence quantum efficiency.