Copper stimulates neonicotinoid insecticide thiacloprid degradation by Ensifer adhaerens TMX-23

AIMS

Aims of this study are to elucidate the molecular mechanism of copper-improved thiacloprid (THI) degradation by Ensifer adhaerens TMX-23 and characterize copper resistance of this strain.

METHODS AND RESULTS

Resting cells of E. adhaerens TMX-23 were used to degrade THI, with formation of THI amide and 98·31% of 0·59 mmol l^-1 THI was degraded in 100 min. The addition of copper improved the degradation of THI and showed little inhibitory effects on the growth of E. adhaerens TMX-23. E. adhaerens TMX-23 degraded THI to THI amide by nitrile hydratases (NhcA and NhpA). QPCR analysis indicated that the expression of nhpA was up-regulated in the presence of copper. E. adhaerens TMX-23 nitrile hydratases were purified, and enzyme assay of NhpA exhibited the highest NHase activity toward THI. The addition of copper activated the activity of NhcA. Soil degradation experiment indicated that E. adhaerens TMX-23 could quickly eliminate THI residual in copper-added soil.

CONCLUSIONS

Copper improved THI degradation by E. adhaerens TMX-23 was attributed to the induced expression of nhpA and activated NhcA.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study broadens the investigation of regulatory mechanism of NHase expression and provided theoretical basis for using metal-resistant microbes to degrade pesticide in heavy metal co-contaminated environments.

[Survey on provincial disease prevention and control professionals' attitudes and cognition to public health physician standardized training in China]

Objective: To understand the attitudes and cognition of disease control and prevention professionals at provincial level on public health physician standardized training and provide evidence for the improvement of the standardized training and exploration of more effective training mode in China. Methods: By cluster sampling, 2 193 professionals at provincial centers for disease control and prevention (CDC) in 6 provinces, including Jiangsu and Guangdong, Shanxi and Hubei,Sichuan and Xinjiang were selected as the study subjects, the sample size was estimated to be 1 933 persons. Results: A total of 1 716 provincial-level CDC professionals were surveyed, the support rate to the standardized training was 70.7%(1 213/1 716). The level of support was negatively associated with the educational level of professionals and their specialty of public health and preventive medicine. Of 875 public health and preventive medicine professionals, 61.6%(318/516) of those with master's degree or above supported the standard training for public health physicians, which was lower than 73.1%(225/308) of those with bachelor's degree and 86.3%(44/51) of those with college degree or below. There were 14.9%(232/1 555) of the respondents suggested a two year training, and 60.4%(933/1 544) suggesting a field training mode. In terms of training content, 86.6%(1 355/1 564) suggesting "epidemiological survey and public health practice", and 76.7%(1 199/1 564) suggesting "basic theories and methodology". Conclusions: In general, the professionals of provincial CDC showed a relatively low interest in the standardized training for public health physicians and failed to reach a consensus. Besides, they were ill-informed about current training duration, method and content. Thas, the professionals at provincial CDC are suggested to be the key target-population whom should be mobilized during the training pilot period, especially the highly educated ones with relevant specialties of public health. It is suggested that public health physician standardized training should to be implemented in whole CDC system to reach full consensus based on its practical achievements and effects. It is also suggested to establish public health graduate medical education system in China.

Metabolomic evaluation of serum metabolites of geese reared at different stocking densities

1. Stocking density is an issue for poultry production. High stocking density can impact biochemical parameters, production, and reproductive performance; however, information regarding the effects of stocking density on serum metabolites in geese is limited.2. Twenty-day-old, Sanhua male geese (n = 240) were allocated to one of two experimental groups for 50 days. One group was housed under a low stocking density (LSD; two birds per m²) and one under a high stocking density (HSD; five birds per m²). Body weight and feed intake were recorded every 10 d. Eight serum samples per group were used for metabonomic analysis by liquid chromatography-mass spectrometry.3. Stocking density did not affect the spleen, liver, thymus, or bursa of Fabricius weights after 50 d. Feed intake and body weight was significantly lower in geese from the HSD group versus the LSD group (P < 0.05). Thirty-six differential serum metabolites were identified (P < 0.05), indicating altered amino acid, carbohydrate, lipid and vitamin cofactor metabolism.4. The results demonstrated that high-density stocking impacts geese, and provides insights into the mechanisms underlying the adverse health effects associated with HSD.

Percutaneous transluminal septal myocardial ablation markedly reduces energy loss in hypertrophic obstructive cardiomyopathy: a four-dimensional flow magnetic resonance imaging study

Background

Functional follow-up modalities of hypertrophic obstructive cardiomyopathy (HOCM) subjected to percutaneous transluminal septal myocardial ablation (PTSMA) are limited mainly to echocardiography and catheterization. Recent advancements in four-dimensional (4D) flow magnetic resonance imaging (MRI) have enabled us to assess patients from the perspective of fluid dynamics by visualising blood flow and calculating quantitative parameters such as wall shear stress and energy loss within cardiac chambers or blood vessels. Several reports have demonstrated that the intra-cardiac energy loss decreased along with improvement of cardiac function achieved by treatment of cardiac diseases. Whether changes in energy loss occur along with PTSMA in HOCM patients and the underlying mechanism remain unknown.

Purpose

This study sought to investigate the influence of PTSMA in patients with HOCM on energy loss in the left ventricle (LV) and aortic root measured by 4D flow MRI.

Methods

We retrospectively recruited HOCM patients who underwent PTSMA at a referral centre from May to November 2019. Patients who underwent 4D flow MRI both before and after PTSMA were included. We collected demographic and clinical data from electronic health records. MRI scans implemented two-dimensional phase-contrast imaging of the three-chamber plane with three-directional velocity, using a 1.5 T scanner. Furthermore, 4D blood flow analysis was performed on off-line saved data, using iTFlow version 1.9. We assessed energy loss in one cardiac cycle within the three-chamber plane of the LV and aortic root (area surrounded by the LV endocardium, sinotubular junction, and mitral annulus).

Results

This study finally included 12 patients, whose mean age was 66±12 years, and 5 (42%) of whom were men. The pressure gradient between the LV apex and ascending aorta was 81±32 mmHg before and 20±22 mmHg immediately after PTSMA (P&lt;0.005, paired). Before PTSMA, 6 patients were in New York Heart Association functional class III and the other 6 in class II. However, after PTSMA, 10 patients improved to class I and 2 to class II. PTSMA reduced energy loss in one cardiac cycle within the three-chamber plane of the LV and aortic root, from 79±36 mJ/m to 55±19 mJ/m (P=0.001, paired).

Conclusions

PTSMA in patients with HOCM reduced energy loss within the LV and aortic root, indicating significant decrease with cardiac workload. Four-dimensional flow MRI of the three-chamber plane to assess energy loss within the LV and aortic root is a time-efficient and reproducible quantitative method to evaluate the effects of PTSMA. Given its non-invasive nature, it also enables to sequentially follow-up HOCM patients who underwent PTSMA.

Periprocedural changes of energy loss

Funding Acknowledgement

Type of funding source: None

Photocatalytic reduction of U(VI) in wastewater by mGO/g-C3N4 nanocomposite under visible LED light irradiation

Efficient elimination of U(VI) from uranium wastewater is an urgent task for sustainable nuclear energy and environmental protection. In this study, magnetic graphene oxide decorated graphitic carbon nitride (mGO/g-C₃N₄) nanocomposite was prepared and used for photocatalytic reduction of U(VI) in wastewater under visible LED light irradiation for the first time. The batch experiments indicated that the mGO/g-C₃N₄ (mGCN) nanocomposite could efficiently reduce U(VI) under visible LED light, and a high U(VI) extraction capacity of 2880.6 mg/g was obtained with an extraction efficiency of 96.02%. The transmission electron microscopy (TEM) elemental mapping, X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) analyses demonstrated that the soluble U(VI) was immobilized by transforming it to metastudtite ((UO₂)O₂·2H₂O) by mGCN nanocomposite under visible LED light irradiation. This work indicated that the mGCN is a promising visible light catalyst for treatment of uranium wastewater.

Overexpression of miR-146a inhibits the apoptosis of hippocampal neurons of rats with cerebral hemorrhage by regulating autophagy

In this study, to investigate the effect of overexpression of miR-146a on autophagy of hippocampal neurons in rats with intracerebral hemorrhage (ICH), 72 Sprague-Dawley rats were randomly divided into the sham, ICH, miR-146a agomir, and miR-146a agomir control groups. The ICH model was constructed by injection of collagenase VII. The apoptosis of hippocampal neurons was measured by TUNEL assay. The levels of LC3 and Beclin 1 were analyzed by immunohistochemistry. Mitochondrial autophagy was examined by transmission electron microscopy. The levels of LC3A, LC3B, Beclin 1, Bax, Bcl-2, and cleaved caspase 3 were examined by Western blot. Western blot was also used to evaluate the expression of nuclear factor κB signaling pathway-related factors. To examine the effect of autophagy inhibitor (3-methyladenine (3-MA)) on miR-146a-regulated apoptotic protein expression, 30 rats were further divided into the sham, ICH, miR-146a agomir, 3-MA, and miR-146a + 3-MA groups. The levels of Bax, Bcl-2, and cleaved caspase 3 were examined by Western blot. Compared with the sham group, the nerve function scores, brain water content, the percentage of apoptotic cells, and the expression levels of LC3, Beclin 1, Bax, cleaved caspase 3, and p-P65 in the hippocampus of rats in the ICH group were all significantly increased (p < 0.05), whereas the expression levels of miR-146a, Bcl-2, and p-IκBα were markedly decreased (p < 0.05). Mitochondrial autophagy was also evident. Furthermore, compared with the ICH group, the results of the abovementioned tests in the miR-146a agomir group were reversed. The overexpression of miR-146a inhibited the autophagy of hippocampal neurons in rats with ICH.

[Reflections on the orientation of public health physicians]

Public health physician is one of the four statutory types of physicians in China, but there is no consensus on their connotation. The main problems are that public health physician is confused with those who perform public health tasks, the relationship between public health physician and clinician and the connotation of prescription right is not clear, and there is limitation in public health education and relevant laws and regulations. Public health physician is positioned as professionals who monitor, investigate, evaluate, and intervene in population health-related issues. It is suggested to retain the practicing qualification of public health physicians and highlight the attribute of public health physicians' prescribing the prescriptions for community health. Encourage public health physicians to obtain qualification for clinicians to individual prescription, Encourage clinicians to access to public health physician qualification. Improve public health school education, take the pilot of public health physician standardization training, cultivate "prevention and treatment combined" physician.

Transport of uranium(VI) in red soil in South China: influence of initial pH and carbonate concentration

Uranium-contaminated wastewater associated with uranium (U) mining and processing inevitably releases into soil environment. In order to assess the risk of U wastewater contamination to groundwater through percolation, U adsorption and transport behavior in a typical red soil in South China was investigated through batch adsorption and column experiments, and initial pH and carbonate concentration were considered of the high-sulfate background electrolyte solution. Results demonstrated that U adsorption isotherms followed the Freundlich model. The adsorption of U to red soil significantly decreased with the decrease of the initial pH from 7 to 3 in the absence of carbonate, protonation-deprotonation reactions controlled the adsorption capacity, and lnC_s had a linear relationship with the equilibrium pH (pH_eq). In the presence of carbonate, the adsorption was much greater than that in the absence of carbonate owing to the pH_eq values buffered by carbonate, but the adsorption decreased with the increase of the carbonate concentration from 3.5 to 6.5 mM. Additionally, the breakthrough curves (BTCs) obtained by column experiments showed that large numbers of H⁺ and CO₃^2- competed with the U species for adsorption sites, which resulted in BTC overshoot (C/C₀ > 1). Numerical simulation results indicated that the BTCs at initial pH 4 and 5 could be well simulated by two-site chemical non-equilibrium model (CNEM), whereas the BTCs of varying initial carbonate concentrations were suitable for one-site CNEM. The fractions of equilibrium adsorption sites (f) seemed to correlate with the fractions of positively charged complexes of U species in solution. The values of partition coefficients (k_d^') were lower than those measured in batch adsorption experiments, but they had the same variation trend. The values of first-order rate coefficient (ω) for all BTCs were low, representing a relatively slow equilibrium between U in the liquid and solid phases. In conclusion, the mobility of U in the red soil increased with the decrease of the initial pH and with the increase of the initial carbonate concentrations.

4-Sulfonylcalix[6]Arene Modified Fe₃O₄@Aspergillus Niger Biosorbents for Effective Removal of Uranium(VI) from Aqueous Solutions

A biosorbent, 4-sulfonylcalix[6]arene modified Fe₃O₄@Aspergillus Niger (MFSC), was successfully prepared through a two-step route for the effective removal of uranium (U(VI)) from aqueous solutions with high selectivity. The structure of MFSC was characterized by FT-IR, SEM, XRD, TGA and VSM, respectively. The impacts of various experimental parameters were investigated in detail. The results indicated that the biosorption of U(VI) on MFSC was mainly attributed to the electrostatic attraction (91% within 8 hours for U(VI)). The adsorption kinetics and adsorption isotherm of U(VI) were found to follow the pseudo second-order model and to be fitted by the Langmuir model, respectively. The thermodynamic parameters revealed that the adsorption process was spontaneous and endothermic. The findings herein highlight the MFSC with high ability for removal of U(VI) from aqueous solutions.

P1643An exploratory analysis for the optimal monitoring interval of N-terminal pro-B-type natriuretic peptide in patients with stable heart failure

Background

N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a potential biomarker for monitoring the status of heart failure. However, the optimal monitoring interval is unknown. This study aims to investigate minimal informative monitoring interval of NT-proBNP in patients with stable chronic heart failure.

Methods

In this retrospective open cohort study, adult patients followed up at a tertiary hospital for chronic heart failure with NT-proBNP measurements were included if they had been previously admitted due to acute heart failure and were free from readmission over 6 months after discharge. We analyzed NT-proBNP measured between 6 months after discharge and the timepoint of an alteration of medication regimen or readmission due to worsening of heart failure. To distinguish actual progression of the disease from biological variability and measurement error, the signal-to-noise ratio method was applied with a random-effects model. Stratified analysis was performed according to underlying risks.

Results

In this analysis, 368 patients were included with NT-proBNP measured between July 2009 and December 2017. The patients had 6.0 times of NT-proBNP measurements in median (interquartile range [IQR] 4.0–10.0) during the follow-up period (median 12.0 months [IQR 6.0–27.0]). In the estimates of the random-effects model, signal (i.e. actual progression of the disease) exceeded noise (i.e. biological variability and measurement error) at 8.1 months (95% confidence interval [CI]: 5.7–10.1) after the index measurement. In a subgroup analysis according to the AHEAD risk score, the minimal informative monitoring interval was shortened as the risk score increased (0–1 point: 12.3 months [95% CI: 10.3–14.5]; 2–3 points: 8.0 months [95% CI: 6.8–9.7]; 4–5 points: 3.3 months [95% CI: 3.0–3.8]; Figure).

Informative intervals stratified by risk

Conclusion

In patients with stable chronic heart failure, the overall minimal informative monitoring interval of NT-proBNP measurement was 8.1 months, which varies by underlying risk. The optimal monitoring interval could be lengthened especially for patients at lower risk.