Search

Background: The re-hospitalization rate of patients with heart failure remains at a high level, and studies of the subject have focused mainly on event-time outcomes. In addition to using re-hospitalization data with the outcomes of the event-time-count, this study introduces the conditional frailty model, which could help obtain more reasonable results., Materials and Methods: This prospective observational cohort study enrolled 1484 patients with heart failure caused by coronary heart disease. The outcomes of heart failure readmissions and the case report form data were collected. Based on the traditional Cox model with event-time outcomes, the mixed effects of a conditional frailty model were added to analyze the event-time-count longitudinal data., Results: The Cox regression model showed that non-manual work, diastolic dysfunction, and better medical compensation increased the risk of heart failure readmission, whereas treatment with beta-blockers decreased the risk. The conditional frailty model further revealed that age, female sex, non-manual work, better medical compensation, longer QRS duration, and treatment with percutaneous coronary intervention increased the risk of heart failure readmission., Conclusion: This study obtained more reliable, reasonable results based on longitudinal data and a mixed model. The results could provide more clinical epidemiological evidence for the management of heart failure., Competing Interests: The authors report no conflicts of interest in this work., (© 2019 Tian et al.)

Photoswitchable components can modulate the properties of metal organic frameworks (MOFs); however, photolabile building blocks remain underexplored. A new strut NPDAC (2-nitro-1,4-phenylenediacetic acid) that undergoes photodecarboxylation has been prepared and incorporated into a MOF, using post-synthetic linker exchange (PSLE) from the structural analogue containing PDAC (p-phenylenediacetic acid). Irradiation of NPDAC-MOF leads to MOF decomposition and concomitant formation of amorphous material. In addition to complete linker exchange, MOFs containing a mixture of PDAC and NPDAC can be obtained through partial linker exchange. In NPDAC30-MOF, which contains approximately 30 % NPDAC, the MOF retains crystallinity after irradiation, but the MOF contains defect sites consistent with loss of decarboxylated NPDAC linkers. The defect sites can be repaired by exposure to additional PDAC or NPDAC linkers at a much faster rate than the initial exchange process. The photoremoval and replacement process may lead to a more general approach to customizable MOF structures., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The practical performance of MnO2 as a capacitor material is limited mainly by its poor electronic conductivity. Arranging MnO2 on the conductive backbone to form a unique hierarchical nanostructure is an efficient way to enhance its capacitor performance. Herein, a hierarchically core-shell structure, in which thin γ-MnO2 sheets are grown on amorphous CoB alloy nano-chains (CoB@MnO2), is produced via a simple and scalable solution-phase procedure at room temperature. A specific capacitance of 612.0 F g-1 is obtained for the CoB@MnO2 capacitor electrode at a discharge current density of 0.5 A g-1, a value higher than those obtained for other conductive materials supported MnO2 electrodes reported in the literature. A rate retention value of 60.9% of its initial capacitance is obtained when the discharge current density increased by 12-fold. It is found that after 6000 charge-discharge cycles at 2 A g-1, the specific performance of CoB@MnO2 is 86.5%. The excellent capacitor performance of CoB@MnO2 is explained to be due to the hierarchical core-shell structure, in which the CoB alloy nano-chain backbone provides a transport pathway for the electron, and the porous MnO2 outer layers provide the channel for mass transfer, hence allowing further exposure to active sites. The combination of high capacitor performance and low-cost synthesis makes the core-shell CoB@MnO2 a promising cathode material for alkaline electrolyte supercapacitors.

In this work, a simple, rapid, sensitive, selective spectrofluorimetric method was applied to detect tartrazine. The fluorescence of acriflavine could be efficiently quenched by tartrazine. The method manifested real time response as well as presented satisfied linear relationship to tartrazine. The linear response range of tartrazine (R 2 = 0.9995) was from 0.056 to 5 μmol L -1 . The detection limit (3σ/k) was 0.017 μmol L -1 , indicating that this method could be applied to detect traces of tartrazine. The accuracy and precision of the method was further assured by recovery studies via a standard addition method, with percentage recoveries in the range of 96.0% to 103.0%. Moreover, a quenching mechanism was investigated systematically by the linear plots at varying temperatures based on the Stern-Volmer equation, fluorescence lifetime and UV-visible absorption spectra, all of which proved to be static quenching. This sensitive, selective assay possessed a great application prospect for the food industry owing to its simplicity and rapidity for the detection of tartrazine., (Copyright © 2017 John Wiley & Sons, Ltd.)

A simple and selective spectrofluorimetric method for the detection of chlortetracycline (CTC) was studied. In pH 7.4 buffer medium l-tryptophan (l-Trp), applied as the fluorescence probe, interacted with CTC resulting in fluorescence quenching of the probe. CTC was detected with maximum excitation and emission wavelengths at λ ex /λ em  = 275/350 nm. Notably, quenching of fluorescence intensities was positively proportional to the CTC concentration over the range of 0.65-30 μmol L -1 and the limit of detection was 0.2 μmol L -1 . Effect of temperature shown in Stern-Volmer plots, absorption spectra and fluorescence lifetime determination, indicated that fluorescence quenching of l-Trp by CTC was mainly by static quenching. The proposed study used practical samples analysis satisfactorily., (Copyright © 2017 John Wiley & Sons, Ltd.)

Diverse and bioactive terpene compounds are produced by marine fungi. The biosynthesis of sesterterpene molecules containing a C25 skeleton is catalyzed by chimeric enzymes that carry out both chain elongation and terpene cyclization reactions. These bifunctional characteristics facilitate using different chain length polyisoprenoid diphosphates as precursors to yield the geranylfarnesyl diphosphate intermediate, which is then converted to a sesterterpene in one step. In this chapter, we describe the identification of sesterterpene synthase enzymes, together with other related enzymes such as diterpene and farnesyl diphosphate synthases, in a single fungal strain. The processes are based on genome sequencing, in silico analysis of terpene synthase, in vivo gene (cluster) deletion and complementation, and in vitro protein function verification, together with the methods of detecting terpenes using high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS)., (© 2018 Elsevier Inc. All rights reserved.)

Interleukin-37 (IL-37) is an inhibitory member of the IL-1 family of cytokines. We previously found that balanced selection maintains common variations of the human IL37 gene. However, the functional consequences of this selection have yet to be validated. Here, using cells expressing exogenous IL-37 variants, including IL-37 Ref and IL-37 Var1 and Var2, we found that the three variants of IL-37 exhibited different immunoregulatory potencies in response to immune stimulation. The protein level of IL-37 Var2 was found to be significantly less than that of IL-37 Ref or Var1, despite the comparable mRNA levels of all three variants. Further study showed that IL-37 Var2 was rapidly degraded by a proteasome-dependent mechanism mediated by enhanced polyubiquitination, leading to a transient upregulation of IL-37 Var2 after immune stimulation. Finally, when ectopically expressed in cells, human IL-37 Var2 exerted less inhibition on proinflammatory cytokine production than did other IL-37 variants. Conversely, purified extracellular IL-37 variant proteins demonstrated comparable inhibitory abilities in vitro. In conclusion, our study reveals that common genetic variants of IL37 lead to different immune-inhibitory potencies, primarily as a result of differences in IL-37 protein stability, suggesting the possible involvement of these variants in various human diseases.

The title complex, [Cu(C9H6NO)2(C5H4N)]·H2O, adopts a slightly distorted square-pyramidal geometry in which the axial pyridine ligand exhibits a long Cu-N bond of 2.305 (3) Å. The pyridine ligand forms dihedral angles of 79.5 (5) and 88.0 (1)° with the planes of the two quinolin-2-olate ligands, while the dihedral angle between the quinoline groups of 9.0 (3)° indicates near planarity. The water mol-ecule connects adjacent copper complexes through O-H⋯O hydrogen bonds to phenolate O atoms, forming a network inter-connecting all the complexes in the crystal lattice.

Metal-free fullerene (C(60)) was found to be an effective catalyst for the reduction of azo groups in basic aqueous solution under UV irradiation in the presence of NaBH(4). Use of NaBH(4) by itself is not sufficient to reduce the azo dyes without the assistance of a metal catalyst such as Pd and Ag. Experimental and theoretical results suggest that C(60) catalyzes this reaction by using its vacant orbital to accept the electron in the bonding orbital of azo dyes, which leads to the activation of the N=N bond. UV irradiation increases the ability of C(60) to interact with electron-donor moieties in azo dyes., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)