[Determination of amanita peptide and tryptamine toxins in wild mushrooms by high performance liquid chromatography-tandem mass spectrometry]

The discovery and identification of mushroom toxins has long been an important area in the fields of toxicology and food safety. Mushrooms are widely favored for their culinary and medicinal value; however, the presence of potentially lethal toxins in some species poses a substantial challenge in ensuring their safe consumption. Therefore, the development of a robust and sensitive analytical method is necessary for accurately identifying the risks associated with mushroom consumption. The study of mushroom toxins, which are characterized by their diversity and substantial variations in chemical structures, present a considerable challenge for achieving precise and high-throughput analysis. To address this issue, the present study employed a robust approach combining a solid-phase extraction (SPE) purification technique with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to establish an analytical method for the detection and quantification of five amatoxins and two tryptamines (psilocybin and bufotenine) present in some mushrooms. Several optimization procedures were undertaken, including optimizing the chromatographic conditions, mass spectrometric parameters, and sample extraction and purification. The procedure involved the extraction of dry mushroom powder with methanol containing 0.3% formic acid, followed by purification using a strong cation exchange cartridge (SCX). The analytes were separated on a T3 chromatographic column (100 mm×2.1 mm, 1.8 μm) using mobile phases of acetonitrile and 5 mmol/L ammonium acetate solution containing 0.1% formic acid. The multiple reaction monitoring (MRM) mode was employed for data acquisition. Amatoxins were quantified using matrix-matched standard calibration curves, whereas isotopic internal standards were used to quantify tryptamine. The results showed that all seven toxins exhibited good linearities (r2>0.99) within the optimized concentration range. The limits of detection (LODs) for bufotenine, psilocybin, and amatoxins were determined as 2.0, 5.0, and 10 μg/kg, respectively, while the limits of quantification (LOQs) were determined as 5.0, 10, and 20 μg/kg, respectively. The LOD and LOQ values further underscore the ability of the method to detect minute quantities of toxins, making it particularly well suited for screening food samples for potential contamination. Using dried shiitake mushroom powder as the matrix, the recoveries of the two tryptamines ranged from 80.6% to 117%, with relative standard deviations (RSDs) ranging from 1.73% to 5.98%, while the recoveries of amatoxins ranged from 71.8% to 115%, with RSDs varying from 2.14% to 9.92% at the three concentration levels. The consistent and satisfactory recoveries of amatoxins and tryptamines demonstrated the ability of this method to accurately quantify the target analytes even in a complex matrix. Comparison with the results of supplementary test method recognized by State Administration for Market Regulation for food (BJS 202008) demonstrated comparable results, indicating no significant differences (p>0.05) in amatoxin contents. The newly developed method is rapid, accurate, precise, meets the required standards, and is suitable for the detection of seven toxins in wild mushrooms. As part of the application of this method, a comprehensive investigation of the distribution of toxins in wild mushrooms from Fujian Province was undertaken. In this study, 59 wild mushroom samples from nine cities were collected in the Fujian province. Species identification was conducted using rDNA-internal transcribed space (rDNA-ITS) molecular barcode technology, which revealed the presence of toxins in the two samples. Notably, one specimen named Amanita fuligineoides contained α-amanitin, β-amanitin, and phalloidin in quantities of 607, 377, and 69.0 mg/kg, respectively. Additionally, another sample, identified as Tricholomataceae, had a psilocybin concentration of 12.6 mg/kg.

REVERSIBLE HYDROGEN AND LITHIUM STORAGE OF MoS2 NANOTUBES

Inorganic fullerene-like MoS 2 nanotubes synthesized by a gas–solid reaction were used as the electrode materials of hydrogen and lithium storage in aqueous and nonaqueous electrolytes, respectively. Very interesting results such as reversible hydrogen reduction/oxidation and lithium insertion have been obtained.

AN OVERVIEW OF DISTANCE AND SIMILARITY MEASURES OF INTUITIONISTIC FUZZY SETS

The Intuitionistic Fuzzy Sets (IFSs), originated by Atanassov [1], is a useful tool to deal with vagueness and ambiguity. In the short time since their first appearance, many different distance and similarity measures of IFSs have been proposed, but they are scattered through the literature. In this paper, we give a comprehensive overview of distance and similarity measures of IFSs. Based on the weighted Hamming distance, the weighted Euclidean distance, and the weighted Hausdorff distance, respectively, we define some continuous distance and similarity measures for IFSs. We also utilize geometric distance model to define some continuous distance and similarity measures for IFSs, which are the various combinations and generalizations of the weighted Hamming distance, the weighted Euclidean distance and the weighted Hausdorff distance. Then we extend these distance and similarity measures for Interval-Valued Intuitionistic Fuzzy Sets (IVIFSs).

EFFECTS OF RAMP ANGLE AND MASS DISTRIBUTIONS ON PASSIVE DYNAMIC GAIT — AN EXPERIMENTAL STUDY

A bipedal walking mechanism with knees is designed and built to study the passive dynamic gait. The effects of changing the ramp angle and the mass distributions of the thighs and the shanks on the gait patterns and walking robustness are studied. It is shown that the changes in the ramp angle and the mass distribution have significant effects on the step lengths and the robustness (the successful rate of launching and the step-count) of the passive gait. More specifically, as the ramp angle increases or the mass center of the entire walker is raised, the step length increases, which dictates the walking speed. However, our experiments show that the changes in the ramp angle and the mass distribution have slight effects on the step period. The optimal ramp angle and mass distribution of the passive walker are also identified, of which the passive walker has the highest successful rate of launching and the step-count. Our experimental results are compared with previous work based on simulations. This research can provide important information for validating/adjusting mathematical models of passive dynamic walking. The work also enables us to gain a better understanding of the mechanics of walking.

Dexmedetomidine attenuates remote lung injury induced by renal ischemia-reperfusion in mice

BACKGROUND

Renal ischemia-reperfusion (I/R) may cause acute lung injury (ALI). The mortality of combined acute kidney injury and ALI is extremely high. Dexmedetomidine, an α(2) adrenergic agonist, exerts potent anti-inflammatory and organoprotective effects in addition to its sedative and analgesic properties. We sought to elucidate whether dexmedetomidine can attenuate lung injury following renal I/R in a murine model of renal I/R.

METHODS

Adult C57BL/6J male mice were randomized to five groups: sham-operated control (Sham); renal I/R (I/R); intraperitoneal injection of dexmedetomidine 25 μg/kg before ischemia (pre-dex) and after perfusion (post-dex); combination of α(2) adrenergic antagonist atipamezole 250 μg/kg prior to dexmedetomidine pre-treatment (atip-dex). Kidney I/R was induced by bilateral renal pedicle clamping for 45 min and followed by 6 h reperfusion. The pulmonary tissues were harvested for histopathological evaluation, wet/dry ratio measurement, biochemical analysis of myeloperoxidase (MPO), Polymerase chain reaction (PCR) determination of Inter-cellular adhesion molecule (ICAM-1) and Tumor necrosis factor - alpha (TNF-α) mRNA.

RESULTS

Renal IR induced significant pulmonary injuries, increased wet/dry ratio together with the enhanced of MPO activities and increased ICAM-1 and TNF-α mRNA level. Both pre- and post-treatment with dexmedetomidine markedly reduced lung edema and inflammatory response and lowered MPO activity and ICAM-1 and TNF-α mRNA expression. The protective effects of dexmedetomidine in the lung were partially reversed by atipamezole, but there were no effect on ICAM-1 and TNF-α mRNA expression level.

CONCLUSIONS

Dexmedetomidine is capable of attenuating remote lung injury induced by renal IR via both α(2) adrenoceptors dependent and independent mechanisms.

Chronic alcoholism increases the induction dose of propofol

BACKGROUND

The present study was designed to investigate the possible effect of chronic alcohol intake on propofol and remifentanil requirements, which was determined by quantifying the 50% (EC(50) ) and 95% (EC(95) ) effective effect-site concentrations for propofol and remifentanil at loss of consciousness (LOC) and after a painful stimulus.

METHODS

Thirty male patients (alcoholic group; n = 30) with chronic alcoholism and 30 patients (control group; n = 30) with a history of small alcohol intake were anaesthetized with propofol and remifentanil by target-controlled infusion. The predicted drug concentrations and Bispectral Index (BIS) values were recorded at LOC and after no response to painful stimuli.

RESULTS

The EC(50) and EC(95) of propofol at LOC in alcoholic group were 3.15 [95% confidence interval (CI), 2.77-3.37] and 4.05 (95% CI, 3.18-5.26) μg/ml, respectively, and those of the control group were 2.21 (95% CI, 1.92-2.86) and 3.04 (95% CI, 2.45-4.64) μg/ml, respectively. The EC(50) and EC(95) of remifentanil measured after no response to painful stimuli in the alcoholic group were 3.02 (95% CI, 2.70-3.38) and 4.98 (95% CI, 4.56-5.89) ng/ml, respectively, and those of the control group were 2.95 (95% CI, 2.68-3.33) and 4.86 (95% CI, 4.55-5.92) ng/ml, respectively. The EC(50) and EC(95) values of propofol at LOC in the control group were significantly lower than that of the alcoholic group.

CONCLUSIONS

These findings suggest that the induction dose requirements of propofol are increased in alcoholic patients anaesthetized with propofol and remifentanil administered by target controlled infusion.

Meningococcal disease in Asia: an under-recognized public health burden

A literature search traced existing information on meningococcal disease in Asia. Reviewed data describing the epidemiology of meningococcal disease in Asia are incomplete, due in part to absence of surveillance in many countries, poor bacterial detection methods and social and healthcare barriers to disease reporting. This suggests that meningococcal disease in some Asian countries may be under-recognized, with a need to introduce/improve existing surveillance and case identification systems. Nevertheless, in some developing Asian countries, the disease burden may be significant. Serogroup A meningococcal epidemics are responsible for high morbidity and mortality in some countries and continue to be an ongoing threat, particularly in developing countries. There is an increasing role played by serogroups C, Y, and W-135 in invasive disease, indicating evolving meningococcal disease epidemiology in some countries. Multivalent meningococcal conjugate vaccines offer new opportunities in the region for reducing the meningococcal disease burden.

Preparation and characterization of hyaluronan/collagen II microspheres under an electrostatic field system with disc electrodes

Collagen II and hyaluronan are the two major components of the native extracellular matrix (ECM). Both biopolymers are responsible for providing the associated tissues with tensile strength, and also serve as a structural scaffold for cell adhesion and growth. Over the years, many researchers have focused on the preparation and evaluation of man-made ECM comprising the two polymers in the form of a membrane for chondrocyte culture applications. Here, a simple and in situ method, involving the injection of the hyaluronan/collagen II (HA/Col II) mixture solution through a pair of hollow-centered parallel disc electrodes (HCPDEs) of a high-voltage electrostatic field system, was developed and employed to prepare HA/Col II microspheres in watery phase. The HA/Col II microspheres were firmed up by a two-step cross-linking treatment (first by FeCl(3) and then by 1-ethyl-3-(3-dimethyl aminopropyl) carbodimide, EDC) to secure the spherical structure shape. Then, at 37 degrees C, reconstitution treatment of the Col II molecules was conducted to further strengthen the microspheres. Depending on treatment conditions, the resulting series of HA/Col II microspheres all exhibited good sphericity in the range of 486+/-43 to 679+/-24microm in diameter. Furthermore, the ratio and amount of HA/Col II in the mixture solutions would affect the morphological structure and basic characteristics, including mechanical strength, thermal properties and water content. In the preliminary study, the HA/Col II microspheres have shown to provide favorable ECM characteristics, with appropriate mechanical strength, and exhibited a 3D inclination.