Sodium-glucose cotransporter 2 inhibitors attenuate vascular calcification by suppressing endoplasmic reticulum protein thioredoxin domain containing 5 dependent osteogenic reprogramming.

AIMS: Vascular calcification is strongly linked to the development of major adverse cardiovascular events, but effective treatments are lacking. Sodium-glucose cotransporter 2 (SGLT2) inhibitors are an emerging category of oral hypoglycemic drugs that have displayed marked effects on metabolic and cardiovascular diseases, including recently reported vascular medial calcification. However, the roles and underlying mechanisms of SGLT2 inhibitors in vascular calcification have not been fully elucidated. Thus, we aimed to further determine whether SGLT2 inhibitors protect against vascular calcification and to investigate the mechanisms involved. METHODS AND RESULTS: A computed tomography angiography investigation of coronary arteries from 1554 patients with type 2 diabetes revealed that SGLT2 inhibitor use was correlated with a lower Agatston calcification score. In the vitamin D3 overdose, 5/6 nephrectomy chronic kidney disease-induced medial calcification and Western diet-induced atherosclerotic intimal calcification models, dapagliflozin (DAPA) substantially alleviated vascular calcification in the aorta. Furthermore, we showed that DAPA reduced vascular calcification via Runx2-dependent osteogenic transdifferentiation in vascular smooth muscle cells (VSMCs). Transcriptome profiling revealed that thioredoxin domain containing 5 (TXNDC5) was involved in the attenuation of vascular calcification by DAPA. Rescue experiments showed that DAPA-induced TXNDC5 downregulation in VSMCs blocked the protective effect on vascular calcification. Furthermore, TXNDC5 downregulation disrupted protein folding-dependent Runx2 stability and promoted subsequent proteasomal degradation. Moreover, DAPA downregulated TXNDC5 expression via amelioration of oxidative stress and ATF6-dependent endoplasmic reticulum stress. Consistently, the class effects of SGLT2 inhibitors on vascular calcification were validated with empagliflozin in intimal and medial calcification models. CONCLUSIONS: SGLT2 inhibitors ameliorate vascular calcification through blocking endoplasmic reticulum stress-dependent TXNDC5 upregulation and promoting subsequent Runx2 proteasomal degradation, suggesting that SGLT2 inhibitors are potentially beneficial for vascular calcification treatment and prevention.

Anomalous origin of the coronary artery: prevalence and coronary artery disease in adults undergoing coronary tomographic angiography.

BACKGROUND: Anomalous aortic origin of a coronary artery (AAOCA) is a rare congenital coronary anomaly with the potential to cause adverse cardiac events. However, there is limited data on the association between AAOCA and coronary artery disease (CAD). Therefore, the aim of this study is to determine the prevalence and symptoms of patients with AAOCA, as well as investigate the correlation between AAOCA and CAD in a population referred for coronary computed tomographic angiography (CTA). METHODS AND RESULTS: All consecutive patients who underwent CTA from 2010 to 2021 were included. Characteristics, symptoms, coronary related adverse events and CTA information were reviewed by medical records. Separate multivariable cumulative logistic regressions were performed, using the stenosis severity in each of the four coronaries as individual responses and as a combined patient clustered response. Finally, we identified 207 adult patients with AAOCA, the prevalence of AAOCA is 0.23% (207/90,501). Moreover, this study found no significant association between AAOCA and CAD. AAOCA did not contribute to higher rates of hospitalization or adverse cardiac events, including calcification. CONCLUSION: AAOCA is a rare congenital disease that is not associated with increased presence of obstructive CAD in adults.

B-type natriuretic peptide levels at admission predict the prognosis of patients with infective endocarditis undergoing cardiac surgery.

Purpose: The objective of this study was to explore the relationship between elevated B-type natriuretic peptide (BNP) levels and the prognosis of patients with infective endocarditis (IE) undergoing cardiac surgery. Methods: In total, 162 IE patients with recorded BNP levels upon admission were included in the present study. The primary end point was all-cause mortality. Results: Multivariate Cox analysis revealed a significant association between log BNP and all-cause mortality. Kaplan-Meier analysis revealed a poorer prognosis for patients with BNP levels ≥ the 75th percentile. Furthermore, the linear trend test indicated a significant link between BNP quartiles and the primary end point within the models. Conclusion: Elevated BNP levels upon admission could predict all-cause mortality in IE patients undergoing cardiac surgery.

Infective endocarditis (IE) refers to an infection affecting the heart lining, heart valves or blood vessels. Despite advancements in medical and surgical interventions, the overall mortality rate remains high among IE patients after surgery. B-type natriuretic peptide (BNP) is a peptide released in response to increased stress on the ventricular and atrial walls and is commonly used as a biomarker for heart failure. This study was aimed to assess the potential of BNP in predicting all-cause mortality in IE patients. The results indicate that elevated BNP levels upon admission could predict a worse prognosis following endocarditis surgery. Additionally, elevated BNP levels upon admission were associated with an increased risk of death.

Effect of Processing on Reduction in Chiral Pesticide Hexaconazole for Kiwifruit Juice.

In this study, the residue levels of chiral pesticide hexaconazole during kiwifruit juice processing (peeling, homogenization, and sterilization) were investigated by using high-performance liquid chromatography (HPLC), and the dietary risk during these processes was also assessed. Hexaconazole was applied at dosages of 173.33 and 346.66 mg/L (recommended and double recommended dosage) in kiwifruit. In the peeling process, 87.7% to 89.2% of the residues were decreased after peeling. Levels of hexaconazole residues in homogenization and sterilization processes further increased from 0.49% to 24.3% and from 0.2% to 3.0%, respectively. Processing factors (PFs) for (+)- and (-)-hexaconazole after peeling, homogenization, and sterilization were 0.12, 0.88, 0.99 for low-dose treatment and 0.12, 0.87, 0.99 for high-dose treatment, respectively. The enantioselectivity of hexaconazole during these procedures was evaluated by enantiomeric fractions (EFs) values, which were around 0.5 throughout all the procedures, indicating that hexaconazole enantiomers had similar dissipation behaviors during kiwifruit juice processing. The RQc of hexaconazole in pre-peeling samples was significantly greater than 100% under two dosages, while the peeling process can notably decrease the values to an acceptable level. The results of this study could provide guidance for agriculture applications and kiwi commodity production to decrease the risk of hexaconazole residue.

Impact of coronary artery disease in patients with hypertrophic cardiomyopathy.

BACKGROUND: Atherosclerotic coronary artery disease (CAD) often occurs concurrently with hypertrophic cardiomyopathy (HCM). However, the influence of concomitant CAD has not been fully assessed in patients with HCM. METHODS: Invasive or computed tomography coronary angiography was performed in 461 patients with HCM at our hospital to determine the presence and severity of CAD from March 2010 to April 2022. The primary end points were all-cause, cardiovascular, and sudden cardiac deaths. The survival of HCM patients with severe CAD was compared with that of HCM patients without severe CAD. RESULTS: Of 461 patients with HCM, 235 had concomitant CAD. During the median (interquartile range) follow-up of 49 (31-80) months, 75 patients (16.3%) died. The 5-year survival estimates were 64.3%, 82.5%, and 86.0% for the severe, mild-to-moderate, and no-CAD groups, respectively (log-rank, p = 0.010). Regarding the absence of cardiovascular death, the 5-year survival estimates were 68.5% for patients with severe CAD, 86.4% for patients with mild-to-moderate CAD, and 90.2% for HCM patients with no CAD (log-rank, p = 0.001). In multivariate analyses, severe CAD was associated with all-cause and cardiovascular death after adjusting for age, left ventricular ejection fraction, hypertension, and atrial fibrillation. CONCLUSIONS: This study showed a worse prognosis among HCM patients with severe CAD than among HCM patients without severe CAD. Therefore, timely recognition of severe CAD in HCM patients and appropriate treatment are important.

Low dosage fluorine ameliorates the bioaccumulation, hepatorenal dysfunction and oxidative stress, and gut microbiota perturbation of cadmium in rats.

Many "hot spot" geographic areas around the world with soils and crops co-polluted with cadmium (Cd) and fluorine (F), two of the most representative pollutants in the environment. However, it still exists argumentative on the dose-effect relationship between F and Cd so far. To explore this, a rat model was established to evaluate the effects of F on Cd-mediated bioaccumulation, hepatorenal dysfunction and oxidative stress, and the disorder of intestinal microbiota as well. 30 healthy rats were randomly assigned to Control group (C group), Cd 1 mg/kg (Cd group), Cd 1 mg/kg and F 15 mg/kg (L group), Cd 1 mg/kg and F 45 mg/kg (M group), and Cd 1 mg/kg and F 75 mg/kg (H group) for 12 weeks by gavage. Our results showed that Cd exposure could accumulate in organs, cause hepatorenal function damage and oxidative stress, and disorder of gut microflora. However, different dosages of F showed various effects on Cd-induced damages in liver, kidney, and intestine, and only the low supplement of F showed a consistent trend. After low supplement of F, Cd levels were declined by 31.29% for liver, 18.31% for kidney, and 2.89% for colon, respectively. The serum aspartate aminotransferase (AST), blood urea nitrogen (BUN), creatinine (Cr), and N-acetyl-ß-glucosaminidase (NAG) were significantly reduced (p < 0.01); The activity of superoxide dismutase (SOD) was elevated and mRNA expression level of NAD(P)H quinone oxidoreductase 1 (NQO1) was decreased in the liver and kidney (p < 0.05). Moreover, low F dosage up-regulated the abundance of Lactobacillus from 15.56% to 28.73% and the 6.23% of F/B ratio was declined to 3.70%. Collectively, this highlights that low dosage of F might be a potential strategy to ameliorate the hazardous effects by Cd-exposed in the environment.

Enantioselective toxicity effect and mechanism of hexaconazole enantiomers to human breast cancer cells.

The toxicity effects of chiral pesticides on living organisms have attracted an increasing public attention. This study aims to investigate the toxicity effect and mechanism of hexaconazole (HEX) to human breast cancer cell (MCF-7) at enantiomer levels. HEX exposure obviously inhibited cells activities in a dose-dependent manner. Under the conditions of VIP >1 and p < 0.05, a total of 255 and 177 differential metabolites (DMs), 17 and 15 amino acid- and lipid-related metabolic pathways were disturbed after (+)-HEX and (-)-HEX exposure, respectively. HEX exposure may affect cell membrane function, signal transduction, and cell differentiation. We further investigated the mechanism of enantioselective differences by using molecular docking which showed that CYP17A1 was the main enzyme that leading to endocrine disrupting effects with the binding energy of -6.30 and -6.08 kcal/mol compared to CYP19A1 enzyme which were -5.81 and -5.93 kcal/mol for (+)-HEX and (-)-HEX, respectively. The docking results explained the reasons why (+)-HEX achieved higher cytotoxicity and induced more seriously metabolic profiles than its antipode. These findings could provide a new insight to understand the enantioselective cytotoxicity effect and mechanism of HEX and will be conducive to assessing its risk to human health at enantiomer levels.

Soil exposure is the major fluoride exposure pathways for residents from the high-fluoride karst region in Southwest China.

In the karst areas of southwest China, soil fluoride levels are higher than in China (478 mg kg-1) and world (200 mg kg-1). High levels of F in the environment might pose a health risk to humans. The comprehensive exposure risk must be studied in this area. Herein, samples of crops and soil were collected from Bijie City, a typical karst area in southwest China, to investigate the pollution level and evaluate the comprehensive F exposure risk. The single-factor index (PFw) and the geological accumulation index (Igeo) were used. The hazard index (HI) was applied to assess exposure risk from multiple exposure routes. The results revealed that there is considerable F contamination in soil and crops in the study area. Average soil total fluorine (Ft) was 1139.13 mg kg-1, and soil water soluble F (Fw) was 3.792 mg kg-1. In corn, rice, wheat, and potatoes, F contents were 1.167-9.585, 1.222-6.698, 1.587-9.976, and 1.797-9.143 mg kg-1, respectively. The mean values of HI were 4.45 and 2.42 for children and adults, respectively, > 1, showing potential health risk exists. Youngsters are at a greater exposure risk than adults. From the results of contribution ratios of different exposure routes for health risk, the major exposure risk was determined to be from soil exposure. Based on this, we suggest that risk managers mainly strive to control the soil fluoride level and implement the risk education and communication.

Determination of cadmium in Chinese pepper and its health implications based on bioaccessibility.

The contamination of cadmium (Cd) in agro-products causes major concern because of its potential dietary risks. In this study, a total of 647 pepper samples from 21 provinces in China were randomly collected according to the distribution of pepper production. Cd pollution levels in Chinses pepper and its health risks were evaluated based on bioaccessibility, which was measured by the physiologically based extraction test (PBET). The results showed that Cd concentration in all pepper ranged from 0.002 to 1.470 mg/kg, with an average of 0.222 mg/kg and a median of 0.132 mg/kg. The highest daily intake of Cd was observed in the female child group (4.037 × 10-5 mg/kg bw/day), which accounted for 4% of the maximum daily permissible dose - 0.001 mg/kg bw/day. The target hazard quotients of Cd were all lower than 1, indicating low potential non-carcinogenic health risks to residents via the consumption of pepper. Notably, carcinogenic risk values suggested potential adverse health effects to adults, while after considering the bioaccessibility of Cd in pepper (mean of 43.07%), those values had fallen under the acceptable level (1 × 10-4). This may indicate that dietary risk assessment of heavy metals in crops could not be conducted just based on their content; the bioaccessibility of metals is also an important factor for consideration.

Spatial distribution and risk assessment of fluorine and cadmium in rice, corn, and wheat grains in most karst regions of Guizhou province, China.

The pollution status of crops planted in Guizhou province of Southwestern China with high background values of Fluorine (F) and Cadmium (Cd) has attracted people's concern. The present study aimed to investigate the spatial distributions of F and Cd in rice, corn and wheat grains, and further evaluate their health risks to residents in Guizhou province. The contents of F and Cd were measured by fluoride ion-selective electrode and inductively coupled plasma mass spectrometry (ICP-MS) methods, respectively. Additionally, the inverse distance weighted (IDW) technique was conducted to analyze spatial distribution, and the health risk was estimated by target hazard quotient (THQ) and hazardous index (HI). The results indicate that Cd contents in samples varied from 0.000 to 0.463 for rice, 0.000 to 0.307 for corn, and 0.012 to 0.537 (mg/kg) for wheat, while F contents ranged from 0.825 to 5.193 (rice), 0.946 to 8.485 (corn), and 0.271 to 9.143 (wheat) mg/kg. The Cd exceeding ratios were 11.600% for rice, 13.500% for corn, and 45.100% for wheat grains, respectively. In terms of spatial distribution, high levels of F and Cd in rice were found in the northern and central in Guizhou, while Cd in corn was distributed in the eastern and F in corn were distributed in the west area of Guizhou. Moreover, the high levels of F and Cd in wheat were distributed in the western and eastern areas. The mean carcinogenic risks (R) of Cd in rice, corn, and wheat in children were 4.150 × 10-4, 1.670 × 10-4 and 3.470 × 10-4, respectively, and that in adults were 3.430 × 10-4, 0.471 × 10-4, and 2.190 × 10-4, respectively. The HI for adults in rice, corn and wheat grains were 0.756, 0.154, and 0.514, respectively, and that for children were 0.913, 0.549, and 0.814, respectively. Collectively, the potential risks produced by F and Cd to the local residents should not be ignored.

Maintenance of recovered dilated cardiomyopathy patients with half-dose neurohumoral blockades (MED-CHARM): A protocol for an open-label, pilot, randomized trial.

Dilated cardiomyopathy (DCM) has brought great damage to the patients' health and social economy. The number of patients with recovered dilated cardiomyopathy (recDCM) has increased over the years as treatment progresses. However, there is a lack of relevant evidence to support the clinical management of patients with recDCM, thereby, the recommendations in guidelines remains sparse. Accordingly, the exploration of recDCM is important to improve patient prognosis and reduce societal burden. This is an open-label, randomized controlled, prospective study that will compare the safety and efficacy of original dose and halved dose of neurohumoral blockades for patients with recDCM. Methods: An open-label, randomized controlled, prospective study will be conducted among eligible patients with recDCM. During the pilot study phase, we will recruit 50 patients. The primary endpoint is hospitalization for heart failure or heart failure relapse within 12 months. Secondary endpoint is major adverse cardiovascular events, including cardiovascular mortality, myocardial infarction, stroke, sustained atrial tachycardia, or ventricular tachycardia. The results will be analyzed using intention-to-treatment analysis. Discussion: The study will provide important evidence of whether it is safe and effective to halve the dosage of neurohumoral blockades in recDCM patients. Trial registration number: ChiCTR2100054051 (www.chictr.org.cn).

Co-exposure of potentially toxic elements in wheat grains reveals a probabilistic health risk in Southwestern Guizhou, China.

Bijie is located at a typical karst landform of Southwestern Guizhou, which presented high geological background values of potentially toxic elements (PTEs). Recently, whether PTE of wheat in Bijie is harmful to human health has aroused people's concern. To this end, the objectives of this study are to determine the concentrations of PTE [chromium (Cr), nickel (Ni), arsenic (As), lead (Pb), cadmium (Cd), and fluorine (F)] in wheat grains, identify contaminant sources, and evaluate the probabilistic risks to human beings. A total of 149 wheat grain samples collected from Bijie in Guizhou were determined using the inductively coupled plasma mass spectrometer (ICP-MS) and fluoride-ion electrode methods. The mean concentrations of Cr, Ni, As, Cd, Pb, and F were 3.250, 0.684, 0.055, 0.149, 0.039, and 4.539 mg/kg, respectively. All investigated PTEs met the standard limits established by the Food and Agriculture Organization except for Cr. For the source identification, Cr and Pb should be originated from industry activities, while Ni, As, and Cd might come from mixed sources, and F was possibly put down to the high geological background value. The non-carcinogenic and carcinogenic health risks were evaluated by the probabilistic approach (Monte Carlo simulation). The mean hazard quotient (HQ) values in the three populations were lower than the safety limit (1.0) with the exception of As (children: 1.03E+00). However, the mean hazard index (HI) values were all higher than 1.0 and followed the order: children (2.57E+00) > adult females (1.29E+00) > adult males (1.12E+00). In addition, the mean carcinogenic risk (CR) values for Cr, As, Pb, and Cd in three populations were all higher than 1E-06, which cannot be negligible. The mean threshold CR (TCR) values were decreased in the order of children (1.32E-02) > adult females (6.61E-03) > adult males (5.81E-03), respectively, all at unacceptable risk levels. Moreover, sensitivity analysis identified concentration factor (C W ) as the most crucial parameter that affects human health. These findings highlight that co-exposure of PTE in wheat grains revealed a probabilistic human health risk. Corresponding measures should be undertaken for controlling pollution sources and reducing the risks for the local populace.

Effect of Bacillus subtilis, Enterococcus faecium, and Enterococcus faecalis supernatants on serotonin transporter expression in cells and tissues.

BACKGROUND: Bacillus subtilis (B. subtilis), Enterococcus faecium (E. faecium), and Enterococcus faecalis (E. faecalis) are probiotics that are widely used in the clinical treatment of irritable bowel syndrome (IBS). Whether the supernatants of these three probiotics can improve gastrointestinal sensation and movement by regulating the serotonin transporter (SERT) expression needs to be clarified. AIM: To investigate whether B. subtilis, E. faecium, and E. faecalis supernatants can upregulate SERT expression in vitro and in vivo. METHODS: Caco-2 and HT-29 cells were stimulated with probiotic culture supernatants for 12 and 24 h, respectively. A male Sprague-Dawley rat model of post-infectious irritable bowel syndrome (PI-IBS) was established and the rats were treated with phosphate-buffered saline (group A) and three probiotics culture supernatants (groups B, C, and D) for 4 wk. The levels of SERT were detected by quantitative PCR and western blotting. RESULTS: The levels of SERT at post-treatment 12 and 24 h were significantly elevated in Caco-2 cells treated with B. subtilis supernatant compared with those in the control group (a P < 0.05). Those levels were markedly upregulated in Caco-2 cells stimulated with E. faecium and E. faecalis supernatants at 24 h (a P < 0.05). In addition, SERT expression in groups B, C, and D was significantly higher than that in group A in the 2nd wk (a P < 0.05). Increased SERT expression was only found in group D in the 3rd wk (a P < 0.05). However, there was no significant difference in SERT expression between the groups in the last week (P > 0.05). CONCLUSION: The supernatants of B. subtilis, E. faecium, and E. faecalis can upregulate SERT expression in intestinal epithelial cells and the intestinal tissues in the rat model of PI-IBS.

The discovery of combined toxicity effects and mechanisms of hexaconazole and arsenic to mice based on untargeted metabolomics.

The high detected frequencies of hexaconazole (Hex) and arsenic (As) increased the probabilities of their co-existence in agricultural products. However, the combined toxicity effect and mechanism of action for these two pollutants were still unclear. In this study, an untargeted metabolomics method with ultra high performance liquid chromatography and tandem mass spectrometry (UPLC-MS/MS) was developed to monitor the changes of endogenous metabolites and metabolism pathways in mice liver. Our study revealed that significant differences in metabolomics profiles were observed after Hex, As, and Hex+As exposure for 90 d. Hex exposure altered 54 metabolites and 11 pathways significantly which were mainly lipid-related. For As exposure, 63 metabolites and 9 pathways were affected most of which were amino acid-related. Hex+As induced 93 metabolites changes with 34% was lipids and lipid-like molecules and 22% was organic acids and derivatives. Hex+As exposure shared the pathways that altered by Hex and As indicated that the interaction of Hex and As might be independent action. The results of this study could provide an important insight for understanding the mechanism of combined toxicity for Hex and As and be helpful for evaluating their health risk to human.

The removal of foreign body ingestion in the upper gastrointestinal tract: a retrospective study of 1,182 adult cases.

BACKGROUND: Foreign body (FB) ingestion in the gastrointestinal tract is a common and urgent problem observed in children and adults. However, there may be difficulty locating FBs and complications associated with their removal. This study aimed to identify risk factors and complications correlated to the presence and removal of FBs. METHODS: This 5-year retrospective study enrolled 1,311 patients between June 2014 and April 2019. Demographic and endoscopic data were collected, containing age, gender, types and location of FBs, duration of FB ingestion, accessory devices, endoscopic methods, and complications. Logistic regression analysis was applied to evaluate the predictive risk factors. RESULTS: Among 1,131 patients, FBs were found in 90.16% of cases. A major predictor for the presence of FB was a presentation of less than 24 hours (h). The types of FBs were jujube pits (36.72%) and fish bones (22.00%), and over 80% of the FBs were discovered in the esophagus. Complications were found in 239 cases (20.22%), of which hemorrhage (162/239, 67.78%) was the most frequent. Age ≥60, duration ≥24 h, and FBs ingested in the esophagus were considered as risk factors for developing complications. CONCLUSIONS: In conclusion, the longer duration, age ≥60, and impaction in the esophagus were risk factors for developing complications following the ingestion of FBs. These factors should be considered when developing assessment and treatment plans in the management of FB ingestion.

Determination of etoxazole in different parts of citrus fruit and its potential dietary exposure risk assessment.

In this study, the profile of etoxazole in whole citrus, peel and pulp samples collected from Chongqing, Guangdong and Anhui provinces was monitored and their dietary risk to human had also been assessed. The final residual levels and distributions of etoxazole in citrus samples were detected by using an ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS). The results showed that final concentrations of etoxazole in whole citrus, peel, and pulp were ranged at 0.012-0.174, 0.010-0.637, and 0.010-0.011 mg kg-1, respectively. The assessment of dietary risk suggested that chronic dietary risk of etoxazole in whole fruit and peel were 0.010-0.197% and 0.035-0.951%, respectively. Our findings indicated that the chronic risk of daily consumption of citrus fruit is acceptable at recommended dosage.

Magnetic hollow bimetallic zinc/cobalt zeolitic imidazolate framework as sorbent for efficiently enriching aflatoxins combined with UHPLC-IT-MSn determination.

A novel magnetic hollow bimetallic zinc/cobalt-based zeolitic imidazolate framework (MHB-Zn/Co-ZIF-8) was prepared via a microwave-assisted chemical etching in methanol. The structure, morphology, and specific surface area were characterized by X-ray diffraction and FTIR spectroscopy, scanning and transmission electron microscopy, and N2 adsorption. The hollow nanostructures with high internal specific surface area, abundant active sites, and reduced aggregation of nanoparticles endow the hollow zeolitic imidazolate framework (ZIF) nanoparticle with high chemical stability, desirable durability, and excellent adsorption abilities. The MHB-Zn/Co-ZIF-8 nanoparticle was used as an effective sorbent for magnetic solid-phase extraction (MSPE) of trace aflatoxins B1, B2, G1, and G2 from fruit juice and fruit samples. The main parameters affecting the efficiency of MSPE procedures were investigated and optimized. The results show that, under optimized conditions, enrichment factors ranging from 67- to 355-fold are obtained for the target analytes. The method is linear in the range 1.0 to 100.0 ng mL-1 with correlation coefficients (R2) from 0.9960 to 0.9992. The limits of detection of four aflatoxins are in the range 0.18 to 1.50 ng mL-1 and the average recoveries range from 75.1 to 102.4%, with relative standard deviations (RSDs) less than 13.6%. This work presents the excellent extraction performance of aflatoxins B1, B2, G1, and G2 on MHB-Zn/Co-ZIF-8. In addition, the applicability of the MSPE coupling with ultrahigh-performance liquid chromatography-ion trap tandem mass spectrometry (UHPLC-IT-MSn) for trace analysis in complex matrices is shown. Graphical abstract Schematic presentation of magnetic hollow bimetallic zinc/cobalt zeolitic imidazolate framework as sorbent for efficiently enriching aflatoxins B1, B2, G1, and G2 from fruit juice samples prior to ultrahigh-performance liquid chromatography-ion trap tandem mass spectrometry (UHPLC-IT-MSn) determination.

A water resistance magnetic graphene-anchored zeolitic imidazolate framework for efficient adsorption and removal of residual tetracyclines in wastewater.

Water-resistant magnetic graphene-anchored zeolite imidazolate (Fe3O4/ZIF-8-G) composite materials with the largest surface area are formed by directly growing a hydrophobic ZIF-8 skeleton onto a graphene support through self-assembly in methanol. Fe3O4/ZIF-8-G hybrid composite has water resistance and super strong adsorption capacity, and is used as an effective adsorbent for adsorption and removal of residual tetracycline in wastewater. The morphologies and structure, as well as water resistance of Fe3O4/ZIF-8-G, were characterized using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetry analysis (TGA), N2 adsorption and pHPZC. The adsorption for tetracycline (TC), oxytetracycline (OTC) and chlortetracycline (CTC) followed pseudo-second-order kinetics and fitted the Freundlich adsorption model with the simultaneous adsorption capacity for TC (382.58 mg g-1), OTC (565.94 mg g-1) and CTC (608.06 mg g-1) at pH 5-6 for 10 h. These were much higher than previously reported results for the removal of tetracycline from aqueous solutions. The used Fe3O4/ZIF-8-G could be effectively reused and recycled at least five times without significant loss of adsorption capacity. The hydrophobic and π-π interaction between the aromatic rings of TCs and the aromatic imidazole rings of the ZIF-8-G framework were the main adsorption mechanism on the surface of Fe3O4/ZIF-8-G. Constructing a hydrophobic surface of ZIF-8/G framework resulted in a reduction of the hydrophilic sites of the surface. This can improve stability and selective adsorption of ZIF-8-G framework. In addition, the results show no significant difference in the adsorption kinetics and adsorption capacity of Fe3O4/ZIF-8-G for TC, OTC and CTC in pure water and wastewater.

[Analysis of monosaccharide composition in polysaccharides from Lycium barbarum L. by precolumn labeling under mild conditions and high-performance liquid chromatography coupled with mass spectrometry].

A method for the separation, identification, and determination of fructose and various aldehyde monosaccharides was established by precolumn labeling with 1-phenyl-3-methyl-5-pyrazolone (PMP) and high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS). The separation was performed on a Kromasil-C18 column (100 mm×4.6 mm, 3.5 µm) with gradient elution. The detection was performed by electrospray ionization mass spectrometry in selected ion monitoring (SIM) mode. In this study, the derivatization mechanism of PMP-labeled fructose was proposed under mild NH3·H2O conditions. The suggested method showed good linearity in the corresponding mass concentration ranges, with the correlation coefficients (r2) > 0.9947. The limits of detection (LODs) and limits of quantification (LOQs) were in the ranges 0.003 to 0.05 mg/L and 0.01 to 0.15 mg/L, respectively. The recoveries in spiked Lycium barbarum L. samples were 65.1% to 116.2%, with relative standard deviations (RSDs) of less than 10.2%. By virtue of its simplicity, high sensitivity, and good repeatability, the method could be successfully applied to the analysis of the monosaccharide composition in polysaccharides of Lycium barbarum L. from four planting areas. Results showed that the isolated polysaccharides comprise mannose, fructose, rhamnose, galactose, glucose, xylose, arabinose, and ribose. The concentration distribution of various monosaccharides differed notably depending on the planted environmention. The proposed method is expected to be of great significance in standardizing the quality control of polysaccharides.