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Se Pu = Chinese Journal of... Nov 2023Organophosphorus flame retardants (OPFRs) have emerged as good alternatives to brominated flame retardants, the use of which is globally restricted. In this study, a...
Organophosphorus flame retardants (OPFRs) have emerged as good alternatives to brominated flame retardants, the use of which is globally restricted. In this study, a screening method based on QuEChERS-gas chromatography-quadrupole time-of-flight mass spectrometry (GC-Q-TOF/MS) was established for the determination of 21 OPFRs in rice. First, full scan (scanning range, 50-450) was performed with a mixed standard solution of the 21 OPFRs (0.1 μg/g) by GC-Q-TOF/MS. The fragmentation pathways of these OPFRs were then investigated to explore their cleavage fragments, the interrelationships among fragments, and the possible cleavage modes of alkylated, chlorinated, and aromatic OPFRs. The retention times, isotopic abundance ratios, and molecular formulas of the characteristic fragments as well as the exact mass of the compounds were obtained to establish a mass spectral library of the OPFRs. Rice samples were extracted and purified by the QuEChERS method, and 0.5% formate acetonitrile solution was used as the extraction solvent; 4 g of magnesium sulfate, 1 g of sodium chloride, 0.5 g of disodium hydrogen citrate, and 1 g of sodium citrate as the extraction-salt combination; and 50 mg of primary secondary amine (PSA), 50 mg of octadecylsilane (C18), and 150 mg of magnesium sulfate as the purification materials. The chromatographic separation of the 21 OPFRs was completed within 16 min under optimized temperature program conditions on the DB-5MS UI column. The screening parameters were optimized, and a full scan of the samples was performed under the following conditions: number of characteristic fragment ions ≥2; accurate mass window=±2×10 (±20 ppm); retention time deviation=±0.2 min, and ion abundance deviation<20%. The developed method was applied to the screening 21 OPFRs in the samples. The results indicated that the matrix interference was greatly reduced by decreasing the extraction accurate mass window, thereby improving the signal-to-noise ratio of the analytes. The targets were extracted from the matrix interference and background noise using deconvolution software, which improved the match between the target compounds and the mass spectral library. The detection rates of alkyl and aromatic OPFRs increased by 22% and 25%, respectively, when the spiking level was increased from 2 to 10 ng/g. Among the chlorinated OPFRs, only tris(2-chloroisopropyl) phosphate (TCIPP) was not detected at a spiking level of 2 ng/g, indicating that chlorinated OPFRs could be identified even at low concentrations. The characteristic ions of the detected compounds matched those of the home-made mass spectral library well, indicating that the practical application of the home-made mass spectral library. The established screening method was applied in the determination of OPFRs in rice samples from different regions in China. A total of 11 OPFRs were detected, among which trimethyl phosphate (TMP), tri-iso-butyl phosphate (TiBP), and tris(3,5-dimethylphenyl) phosphate (T35DMPP) had the highest detection rates. These results indicate that these three OPFRs are widely used and can easily come into contact with rice samples through various routes. Differences in the types of OPFRs detected in the actual samples may be related to the types of OPFRs produced in local factories. OPFRs can be detected in rice samples by the developed GC-Q-TOF/MS screening method, which is helpful for the identification of OPFRs in complex matrix samples.
Topics: Organophosphorus Compounds; Flame Retardants; Oryza; Magnesium Sulfate; Gas Chromatography-Mass Spectrometry; Phosphates
PubMed: 37968821
DOI: 10.3724/SP.J.1123.2023.08022 -
Se Pu = Chinese Journal of... Nov 2023A method for the determination of seven mycotoxins in rice and wheat by ultra performance liquid chromatography-quadrupole-time of flight mass spectrometry...
A method for the determination of seven mycotoxins in rice and wheat by ultra performance liquid chromatography-quadrupole-time of flight mass spectrometry (UPLC-Q-TOF/MS) based on self-built database was established. Samples were extracted with 0.2% formic acid aqueous solution-acetonitrile (50∶50, v/v), dehydrated and salted according to the QuEChERS method (4 g of magnesium sulfate, 1 g of sodium chloride, 1 g of sodium citrate, 0.5 g of citrate disodium salt), and separated on an HSS T3 column (100 mm×2.1 mm, 1.8 μm). UPLC-Q-TOF/MS with MS screening was performed, and the positive and negative ions of the screened mycotoxins were calibrated and quantified using matrix-matched standard curves with time of flight multiple reaction monitoring (TOF-MRM). The results showed that aflatoxin G (AFG), aflatoxin G (AFG), aflatoxin B (AFB), aflatoxin B (AFB), and ochratoxin A (OTA) exhibited moderate matrix effects in rice, while OTA and zearalenone (ZEN) exhibited moderate matrix effects in wheat. The seven mycotoxins showed good linearities in their respective concentration ranges, with correlation coefficients () of 0.9900-0.9998. The limits of detection (LODs) for rice and wheat were 0.50-400 and 0.50-200 μg/kg, respectively, and the limits of quantification (LOQs) for both cereals were 1.00-800 μg/kg. In rice, the average recoveries at three spiked levels of low, medium, and high were 88.1%-123.9%, with relative standard deviations (RSDs) of 0.2%-13.6%. In wheat, the average recoveries at three spiked levels of low, medium, and high were 102.0%-123.4%, with RSDs of 0.8%-14.8%. As a result, one batch of 46 batches of rice was screened out for AFB and AFB, with a screening rate of 2.2%, of which the measured values were 10.8 μg/kg and 1.2 μg/kg, respectively. According to GB 2761-2017, the maximum allowable level of AFB in rice is 10 μg/kg; thus, the exceeding rate for AFB is 2.2%. Deoxynivalenol (DON) was screened out in 9 out of 24 batches of wheat (screening rate, 37.5%), while ZEN was screened out in 19 batches (screening rate, 79.2%). According to GB 2761-2017, the maximum allowable levels of DON and ZEN in wheat are 1000 and 60 μg/kg, respectively. The levels of DON and ZEN detected in the wheat samples did not exceed these limits. The proposed method uses MS for qualitative screening to avoid the occurrence of false positives caused by interfering compounds with mass numbers and retention times similar to those of the analytes. TOF-MRM mode is then used to quantify the positively screened mycotoxins. The method is fast, accurate, sensitive, and suitable for the isolation and quantitative detection of mycotoxin residues in rice and wheat samples. The findings provide powerful technical support for mycotoxin contamination monitoring in rice and wheat and early risk-warning efforts.
Topics: Mycotoxins; Edible Grain; Chromatography, High Pressure Liquid; Tandem Mass Spectrometry; Chromatography, Liquid; Zearalenone
PubMed: 37968819
DOI: 10.3724/SP.J.1123.2023.07014 -
The Journal of Clinical Investigation Jan 2024Cholera is a global health problem with no targeted therapies. The Ca2+-sensing receptor (CaSR) is a regulator of intestinal ion transport and a therapeutic target for...
Cholera is a global health problem with no targeted therapies. The Ca2+-sensing receptor (CaSR) is a regulator of intestinal ion transport and a therapeutic target for diarrhea, and Ca2+ is considered its main agonist. We found that increasing extracellular Ca2+ had a minimal effect on forskolin-induced Cl- secretion in human intestinal epithelial T84 cells. However, extracellular Mg2+, an often-neglected CaSR agonist, suppressed forskolin-induced Cl- secretion in T84 cells by 65% at physiological levels seen in stool (10 mM). The effect of Mg2+ occurred via the CaSR/Gq signaling that led to cAMP hydrolysis. Mg2+ (10 mM) also suppressed Cl- secretion induced by cholera toxin, heat-stable E. coli enterotoxin, and vasoactive intestinal peptide by 50%. In mouse intestinal closed loops, luminal Mg2+ treatment (20 mM) inhibited cholera toxin-induced fluid accumulation by 40%. In a mouse intestinal perfusion model of cholera, addition of 10 mM Mg2+ to the perfusate reversed net fluid transport from secretion to absorption. These results suggest that Mg2+ is the key CaSR activator in mouse and human intestinal epithelia at physiological levels in stool. Since stool Mg2+ concentrations in patients with cholera are essentially zero, oral Mg2+ supplementation, alone or in an oral rehydration solution, could be a potential therapy for cholera and other cyclic nucleotide-mediated secretory diarrheas.
Topics: Mice; Humans; Animals; Receptors, Calcium-Sensing; Magnesium; Cholera Toxin; Cholera; Calcium; Escherichia coli; Colforsin; Intestinal Mucosa; Diarrhea; Epithelial Cells; Dietary Supplements
PubMed: 37962961
DOI: 10.1172/JCI171249 -
Tropical Animal Health and Production Nov 2023There are no available data regarding the hematology, serum biochemistry, and fore stomach fluid constituents of llama (Lama glama) in Egypt. This study aimed to...
There are no available data regarding the hematology, serum biochemistry, and fore stomach fluid constituents of llama (Lama glama) in Egypt. This study aimed to establish normal reference values for blood and fore stomach fluid constituents of llama and determine the influence of sex and season on these parameters under Egyptian conditions. The study was performed on (n = 38; 22 female, 16 male; 1-7 years) apparently healthy llamas located in the Giza Zoo and private zoo in the Ismailia Governorate. Samples were collected in two seasons and divided into summer and winter samples. Differences in the mean and range values of packed cell volume, serum minerals, fore stomach fluid pH, and total protozoal count in Egypt were recorded. Sex and season had minimal effects on hematology and only erythrocyte count showed a significant (p < 0.05) increase in males compared with females. Regarding serum biochemistry, males showed significant (p < 0.05) increases in alanine transaminase and calcium levels, while globulin significantly (p < 0.05) increased in females. The influence of season on serum biochemistry was evident in alanine transaminase, total protein, albumin, and chloride which increased significantly (p < 0.05) in summer, while urea, bilirubin, and magnesium increased significantly (p < 0.05) in winter. Fore stomach fluid pH and ammonia showed significant (p < 0.05) increases in winter, while the total protozoal count increased significantly (p < 0.05) in summer and in males compared with females. The results obtained in this study can serve as reference values for the hematobiochemical and fore stomach fluid constituents of llama in Egypt.
Topics: Female; Male; Animals; Camelids, New World; Egypt; Alanine Transaminase; Erythrocyte Count; Camelidae
PubMed: 37953386
DOI: 10.1007/s11250-023-03820-z -
BMC Plant Biology Nov 2023γ-aminobutyric acid (GABA), as a regulator of many aspects of plant growth, has a pivotal role in improving plant stress resistance. However, few studies have focused...
Exogenous γ-aminobutyric acid improves the photosynthesis efficiency, soluble sugar contents, and mineral nutrients in pomegranate plants exposed to drought, salinity, and drought-salinity stresses.
BACKGROUND
γ-aminobutyric acid (GABA), as a regulator of many aspects of plant growth, has a pivotal role in improving plant stress resistance. However, few studies have focused on the use of GABA in increasing plants' resistance to interactional stresses, such as drought-salinity. Therefore, the focus of this study was to examine the effect of foliar application of GABA (0, 10, 20, and 40 mM) on growth indices and physio-biochemical parameters in plants of two pomegranate cultivars, 'Rabab' and 'Atabaki' exposed to drought, salinity, and drought-salinity.
RESULTS
Under stress conditions, the photosynthetic capacity of two pomegranate cultivars, including transpiration rate, net photosynthetic rate, intercellular carbon dioxide concentration, stomatal conductance of water vapour, and mesophyll conductance, was significantly reduced. This resulted in a decrease in root morphological traits such as fresh and dry weight, diameter, and volume, as well as the fresh and dry weight of the aerial part of the plants. However, the application of GABA reversed the negative effects caused by stress treatments on growth parameters and maintained the photosynthetic capacity. GABA application has induced the accumulation of compatible osmolytes, including total soluble carbohydrate, starch, glucose, fructose, and sucrose, in charge of providing energy for cellular defense response against abiotic stresses. Analysis of mineral nutrients has shown that GABA application increases the absorption of potassium, potassium/sodium, magnesium, phosphorus, manganese, zinc, and iron. As concentration increased up to 40 mM, GABA prevented the uptake of toxic ions, sodium and chloride.
CONCLUSIONS
These findings highlight the potential of GABA as a biostimulant strategy to enhance plant stress tolerance.
Topics: Pomegranate; Sugars; Salinity; Droughts; Photosynthesis; gamma-Aminobutyric Acid; Stress, Physiological; Sodium; Salt Stress; Potassium; Nutrients; Minerals
PubMed: 37926819
DOI: 10.1186/s12870-023-04568-2 -
Kidney International Feb 2024Acute electrolyte and acid-base imbalance is experienced by many children following kidney transplant. This is partly because doctors give very large volumes of... (Randomized Controlled Trial)
Randomized Controlled Trial
Acute electrolyte and acid-base imbalance is experienced by many children following kidney transplant. This is partly because doctors give very large volumes of artificial fluids to keep the new kidney working. When severe, fluid imbalance can lead to seizures, cerebral edema and death. In this pragmatic, open-label, randomized controlled trial, we randomly assigned (1:1) pediatric kidney transplant recipients to Plasma-Lyte-148 or standard of care perioperative intravenous fluids (predominantly 0.45% sodium chloride and 0.9% sodium chloride solutions). We then compared clinically significant electrolyte and acid-base abnormalities in the first 72 hours post-transplant. The primary outcome, acute hyponatremia, was experienced by 53% of 68 participants in the Plasma-Lyte-148 group and 58% of 69 participants in the standard fluids group (odds ratio 0·77 (0·34 - 1·75)). Five of 16 secondary outcomes differed with Plasma-Lyte-148: hypernatremia was significantly more frequent (odds ratio 3·5 (1·1 - 10·8)), significantly fewer changes to fluid prescriptions were made (rate ratio 0·52 (0·40-0·67)), and significantly fewer participants experienced hyperchloremia (odds ratio 0·17 (0·07 - 0·40)), acidosis (odds ratio 0·09 (0·04 - 0·22)) and hypomagnesemia (odds ratio 0·21 (0·08 - 0·50)). No other secondary outcomes differed between groups. Serious adverse events were reported in 9% of participants randomized to Plasma-Lyte-148 and 7% of participants randomized to standard fluids. Thus, perioperative Plasma-Lyte-148 did not change the proportion of children who experienced acute hyponatremia compared to standard fluids. However fewer fluid prescription changes were made with Plasma-Lyte-148, while hyperchloremia and acidosis were less common.
Topics: Humans; Child; Sodium Chloride; Hyponatremia; Kidney Transplantation; Electrolytes; Acidosis; Water-Electrolyte Imbalance; Fluid Therapy; Isotonic Solutions; Gluconates; Potassium Chloride; Magnesium Chloride; Sodium Acetate
PubMed: 37914088
DOI: 10.1016/j.kint.2023.09.032 -
Microorganisms Sep 2023Concrete is the most utilized construction material worldwide. In the marine environment, it is subject to chemical degradation through reactions with chloride (the most... (Review)
Review
Concrete is the most utilized construction material worldwide. In the marine environment, it is subject to chemical degradation through reactions with chloride (the most important ion), and sulfate and magnesium ions in seawater, and to biodeterioration resulting from biological (initially microbiological) activities, principally acid production. These two types of corrosions are reviewed and the failure of attempts to predict the degree of deterioration resulting from each is noted. Chemical (abiotic) corrosion is greatest in the splash zone of coastal constructions, while phenomenological evidence suggests that biodeterioration is greatest in tidal zones. There have been no comparative experiments to determine the rates and types of microbial biofilm formation in these zones. Both chemical and microbiological concrete deteriorations are complex and have not been successfully modeled. The interaction between abiotic corrosion and biofilm formation is considered. EPS can maintain surface hydration, potentially reducing abiotic corrosion. The early marine biofilm contains relatively specific bacterial colonizers, including cyanobacteria and proteobacteria; these change over time, producing a generic concrete biofilm, but the adhesion of microorganisms to concrete in the oceans has been little investigated. The colonization of artificial reefs is briefly discussed. Concrete appears to be a relatively prescriptive substrate, with modifications necessary to increase colonization for the required goal of increasing biological diversity.
PubMed: 37894096
DOI: 10.3390/microorganisms11102438 -
International Journal of General... 2023Low volume change and minimal trauma observed during angiography are the reason why physicians often overlook any changes affecting pre-operative electrolytes levels...
BACKGROUND
Low volume change and minimal trauma observed during angiography are the reason why physicians often overlook any changes affecting pre-operative electrolytes levels after coronary intervention. However, few studies have addressed the issue of electrolyte changes after the coronary intervention. Therefore, our study investigates coronary angiography's effect on electrolytes and provides the quick identification of groups more prone to electrolyte changes.
METHODS
From the department of cardiology of the second affiliated hospital of Shandong's first medical university, 374 patients undergoing coronary angiography were selected. Pre-intervention and post-intervention serums, sodium (Na), potassium (K), chloride (Cl), magnesium (Mg) and renal function were analyzed. The correlation between influential factors was also assessed. The association of hypokalemia with short-major adverse cardiac events (MACE) and arrhythmia was evaluated.
RESULTS
Among the 374 subjects including 264 patients who had a simple angiography and 110 patients who received coronary artery interventional therapy. A decrease in potassium levels was found in 81.8% of the patients, and post-interventional hypokalemia was observed in 15.0%. After the intervention, the hypokalemia among males was 2.18 times than that of females, and the pre-operative serum potassium level was 3.5mmol/L≤K<4.0mmol/L and was 2.09 times than that of K≥4.0 mmol/L, but was not associated with age and either simple coronary angiography or PCI (percutaneous coronary intervention). Hypernatremia was also prevalent in males under 60 years and with pre-operative hypernatremia. Significant variations were found between hypokalemia and influential factors like hypertension, diabetes, and gastrointestinal disease. We also found that there was no obvious correlation between hypokalemia and recurrent angina, heart failure and death, but significantly increased the risk of some arrhythmias.
CONCLUSION
Male patients are more likely to suffer from electrolyte disturbance after coronary intervention. There is a need to emphasize monitoring and managing electrolyte changes to prevent severe complications in the peri-operative period.
PubMed: 37868813
DOI: 10.2147/IJGM.S430510 -
Molecular Therapy. Methods & Clinical... Dec 2023Recombinant adeno-associated viral vector (rAAV) mediated gene therapy is gaining traction in treating genetic disorders. Current rAAV production systems yield a mixture...
Recombinant adeno-associated viral vector (rAAV) mediated gene therapy is gaining traction in treating genetic disorders. Current rAAV production systems yield a mixture of capsids largely devoid of the transgene (empty capsid) compared with the desired therapeutic product (full capsid). Anion exchange chromatography (AEX) is an attractive method for separating empty and full AAV capsids because of its scalability. Resin types and buffer composition are key considerations for AEX and must support capsid stability to be suitable for downstream processing. We examined the impact of binding durations (0-8 h) using various binding ionic strengths (15-75 mM), pH (7.5-9.0), resin chemistry (POROS XQ, POROS HQ, POROS I, and BIA QA monolith), and proprietary Q resins with different ligand densities for effects on capsid stability. Empty capsids were altered upon extended binding, leading to retention time shifts and loss of resolution between empty and full capsids. Viral capsid protein analysis reveals that full capsids have more viral capsid protein 3 (VP3) proteins than empty capsids. Analytical hydrophilic liquid chromatography showed that empty capsid retention time shift is accompanied by changes to the empty capsid's native VP3 protein. Among the potential stabilizing additives considered, magnesium chloride was the most effective at reducing negative impacts caused by extended binding.
PubMed: 37868210
DOI: 10.1016/j.omtm.2023.101112 -
Frontiers in Veterinary Science 2023This study aimed to establish baseline variables for calves transported by road and ferry from Ireland to the Netherlands and to investigate the effect of journey [two...
This study aimed to establish baseline variables for calves transported by road and ferry from Ireland to the Netherlands and to investigate the effect of journey [two comparable journeys in April (J1) and May (J2) 2022] and source [source farm or mart (SF/MA)] on these variables. A total of 66 calves from the SF/MA were transported from Ireland to commercial veal farms in the Netherlands. Blood samples were collected at the SF/MA, assembly center (Ireland), lairage (France), and on arrival on the veal farm (Netherlands). They were analyzed for indicator variables related to energy balance, hydration/electrolytes, physical/muscular stress, immunity, and inflammation [glucose, beta-hydroxybutyrate (BHB), non-esterified fatty acids (NEFA), potassium, sodium, magnesium, chloride, urea, haematocrit, total protein, creatine kinase, L-lactate, cortisol, white blood cell, neutrophil, lymphocyte and monocyte counts, serum amyloid-A, and haptoglobin]. Health variables eye and nose discharge, skin tent (a measure of dehydration), and navel inflammation were scored by a trained observer, and calves were weighed at every blood-sampling time point. All blood variables and body weight changed significantly ( < 0.05) during transport, most notably between the assembly center and lairage. Reference ranges were available for 18 variables; 11 of these variables exceeded the reference ranges at the lairage, whilst 10 variables exceeded the reference ranges on arrival at the veal farm. However, health variables did not change during transport. A journey-to-journey comparison indicated much variation; 18 out of 25 variables differed significantly on at least one time point. In total, J1 calves experienced a more severe change in BHB, potassium, strong-ion-difference, L-lactate, and eye and nose discharge than J2 calves. The source of calves also affected their physiology; 12 out of 25 variables studied differed significantly, all of which were confined to the first time point. Specifically, MA calves had elevated levels of NEFA, urea, haematocrit, L-lactate, cortisol, white blood cell, neutrophil, and monocyte counts and lower levels of corrected chloride and lymphocyte count. Overall, calves in this study showed a generalized physiological disturbance beyond reference limits during long-distance transport, but no animal died during transport or for 3 weeks post-arrival.
PubMed: 37829357
DOI: 10.3389/fvets.2023.1238734