Similarities and differences of myocardial metabolic characteristics between HFpEF and HFrEF mice based on LC-MS/MS metabolomics / 中华心血管病杂志

Objective: To reveal the similarities and differences in myocardial metabolic characteristics between heart failure with preserved ejection fraction (HFpEF) and heart failure with reduced ejection fraction (HFrEF) mice using metabolomics. Methods: The experimental mice were divided into 4 groups, including control, HFpEF, sham and HFrEF groups (10 mice in each group). High fat diet and Nω-nitroarginine methyl ester hydrochloride (L-NAME) were applied to construct a"two-hit"HFpEF mouse model. Transverse aortic constriction (TAC) surgery was used to construct the HFrEF mouse model. The differential expression of metabolites in the myocardium of HFpEF and HFrEF mice was detected by untargeted metabolomics (UHPLC-QE-MS). Variable importance in projection>1 and P<0.05 were used as criteria to screen and classify the differentially expressed metabolites between the mice models. KEGG functional enrichment and pathway impact analysis demonstrated significantly altered metabolic pathways in both HFpEF and HFrEF mice. Results: One hundred and nine differentially expressed metabolites were detected in HFpEF mice, and 270 differentially expressed metabolites were detected in HFrEF mice. Compared with the control group, the most significantly changed metabolite in HFpEF mice was glycerophospholipids, while HFrEF mice presented with the largest proportion of carboxylic acids and their derivatives. KEGG enrichment and pathway impact analysis showed that the differentially expressed metabolites in HFpEF mice were mainly enriched in pathways such as biosynthesis of unsaturated fatty acids, ether lipid metabolism, amino sugar and nucleotide sugar metabolism, glycerophospholipid metabolism, arachidonic acid metabolism and arginine and proline metabolism. The differentially expressed metabolites in HFrEF mice were mainly enriched in arginine and proline metabolism, glycine, serine and threonine metabolism, pantothenate and CoA biosynthesis, glycerophospholipid metabolism, nicotinate and nicotinamide metabolism and arachidonic acid metabolism, etc. Conclusions: HFpEF mice have a significantly different myocardial metabolite expression profile compared with HFrEF mice. In addition, biosynthesis of unsaturated fatty acids, arachidonic acid metabolism, glycerophospholipid metabolism and arginine and proline metabolism are significantly altered in both HFpEF and HFrEF mice, suggesting that these metabolic pathways may play an important role in disease progression in both types of heart failure.

Detection of Carbamazepine and Its Metabolites in Blood Samples by LC-MS/MS / 法医学杂志

OBJECTIVES@#To establish a method for the detection of carbamazepine and its metabolites 10,11-dihydro-10,11-epoxycarbamazepine and 10,11-dihydro-10-hydroxycarbamazepine in blood samples by liquid chromatography-tandem mass spectrometry (LC-MS/MS).@*METHODS@#The blood samples were treated with 1-butyl-3-methylimidazolium hexafluorophosphate as an extraction solvent. The samples were extracted by ultrasound-assisted extraction and separated by ZORBAX Eclipse Plus C18, 95Å column. The mobile phase A aqueous solution containing 0.1% formic acid and 10 mmol/L ammonium acetate, and mobile phase B mixed organic solvent containing acetonitrile/methanol (Vacetonitrile∶Vmethanol=2∶3) were used for gradient elution at the flow rate of 1.00 mL/min. An electrospray ion source in positive mode was used for detection in the multiple reaction monitoring.@*RESULTS@#The linearities of carbamazepine and its metabolites 10,11-dihydro-10,11-epoxycarbamazepine and 10,11-dihydro-10-hydroxycarbamazepine in blood samples were good within the corresponding range, with correlation coefficients (r) greater than 0.995 6. The limits of detection were 3.00, 0.40 and 1.30 ng/mL, respectively. The limit of quantitation were 8.00, 1.00 and 5.00 ng/mL, respectively. The extraction recoveries ranged from 76.00% to 106.44%. The relative standard deviations of the intra-day and inter-day precisions were less than 16%. Carbamazepine and its main metabolite 10,11-dihydro-10,11-epoxycarbamazepine were detected in blood samples of death cases with a mass concentration of 2.71 μg/mL and 252.14 ng/mL, respectively.@*CONCLUSIONS@#This method has high sensitivity and good selectivity, which is suitable for the detection of carbamazepine and its metabolites in blood samples, and can be used for carbamazepine-related forensic identifications.

Screening the effective components in treating dampness stagnancy due to spleen deficiency syndrome and elucidating the potential mechanism of Poria water extract / 中国天然药物

Poria is an important medicine for inducing diuresis to drain dampness from the middle energizer. However, the specific effective components and the potential mechanism of Poria remain largely unknown. To identify the effective components and the mechanism of Poria water extract (PWE) to treat dampness stagnancy due to spleen deficiency syndrome (DSSD), a rat model of DSSD was established through weight-loaded forced swimming, intragastric ice-water stimulation, humid living environment, and alternate-day fasting for 21 days. After 14 days of treatment with PWE, the results indicated that PWE increased fecal moisture percentage, urine output, D-xylose level and weight; amylase, albumin, and total protein levels; and the swimming time of rats with DSSD to different extents. Eleven highly related components were screened out using the spectrum-effect relationship and LC-MS. Mechanistic studies revealed that PWE significantly increased the expression of serum motilin (MTL), gastrin (GAS), ADCY5/6, p-PKAα/β/γ cat, and phosphorylated cAMP-response element binding protein in the stomach, and AQP3 expression in the colon. Moreover, it decreased the levels of serum ADH, the expression of AQP3 and AQP4 in the stomach, AQP1 and AQP3 in the duodenum, and AQP4 in the colon. PWE induced diuresis to drain dampness in rats with DSSD. Eleven main effective components were identified in PWE. They exerted therapeutic effect by regulating the AC-cAMP-AQP signaling pathway in the stomach, MTL and GAS levels in the serum, AQP1 and AQP3 expression in the duodenum, and AQP3 and AQP4 expression in the colon.

Effects of Buyang Huanwu Decoction on Intestinal Barrier, Intestinal Flora, and Trimethylamine Oxide in Rats with Heart Failure / 中国结合医学杂志

OBJECTIVE@#To explore the mechanisms of Buyang Huanwu Decoction (BYHWD) modulating the gut microbiome and trimethylamine oxide (TAMO) to exert cardioprotective effects.@*METHODS@#Ligation of the left anterior descending coronary artery was performed in rats to induce heart failure (HF). Except for the sham-operation group (n=10), 36 operation-induced models were randomized into 3 groups using a random number table (n=12 in each group): the model group, the BYHWD group (15.02 g/kg BYHWD), and the positive group (4.99 g/kg metoprolol succinate). After 4-week treatment (once daily by gavage), echocardiography was applied to evaluate the cardiac function and the Tei index (the ratio of ventricular isovolumic contraction time (IVCT) and isovolumic diastolic time (IVRT) to ejection time (ET)) was calculated; hematoxylin-eosin (HE) staining was observed to characterize the pathology of the myocardium and small intestinal villi. D-lactic acid was detected by an enzyme-linked immunosorbent assay (ELISA). Expressions of occludin, claudin-1, and zonula occludens (ZO-1) were detected by Western blot. 16S ribosomal ribonucleic acid (16S rRNA) sequencing was used to explore the changes in the intestinal flora. TMAO was detected via liquid chromatography-tandem mass spectrometry (LC-MS/MS).@*RESULTS@#In the echocardiography, the Tei index was considerably lower in the positive and BYHWD groups compared with the model group (P<0.05). Besides, BYHWD improved the pathology of myocardium and small intestine of HF rats and lowered the D-lactic acid content in the serum, when compared with the model group (P<0.05). BYHWD also improved the expression of occludin and claudin-1 (P<0.05); in the gut microbiota analysis, BYHWD slowed down modifications in the structure distribution of gut microbiota and regulated the diversity of intestinal flora in HF rats. The content of TMAO in the serum was significantly lowered by BYWHT compared with the model group (P<0.05).@*CONCLUSION@#BYHWD may delay progression of HF by enhancing the intestinal barrier structure, and regulating intestinal flora and TAMO.

Determination of misoprostol in workplace air by high performance liquid chromatography / 中华劳动卫生职业病杂志

Objective: To establish a high performance liquid chromatography method for the determination of misoprostol in workplace air. Methods: From February to August 2021, the misoprostol in the workplace air was collected by glass fiber filter membrane, and theeluent was separated by C18 liquid chromatography column, determined by UV detector, and quantified by external standard method. Results: The quantitative lower limit of misoprostol determination method was 0.05 μg/ml, and the lowest quantitative concentration was 1.4 μg/m(3) (calculated by collecting 75 L air sample). The concentration of misoprostol has a good linear relationship between 0.05 to 10.00 μg/ml. The relative coefficient was 0.9998. The regression equation of the standard working curve was y=495759x-45257. The range of average recovery rates were from 95.5% to 102.8%. The intra-assay precision of the method was 1.2%-4.6%, and the inter-assay precision was 2.0%-5.9%. The samples could be stored stably for 7 days at 4 ℃. Conclusion: The high performance liquid chromatography method for the determination of misoprostol has high sensitivity, good specificity and simple procedure of sample pretreatment. It is suitable for the detection of misoprostol in the workplace air.

Determination of 22 phospholipids in serum by ultra performance liquid chromatography-tandem mass spectrometry / 中华劳动卫生职业病杂志

Objective: To establish ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the determination of 22 phospholipids in serum. Methods: In September 2022, Using synthetic non endogenous phospholipids as internal standard, phospholipids in serum were extracted by methanol-dichloromethane (2∶1, V/V) protein precipitation method. Chromatographic separation was achieved on an ACQUITY UPLC BEH shield RP18 column, and the mobile phase was methanol/water (5∶95, V/V) containing 10 mM ammonium formate and methanol. Detection was performed in multiple reaction monitoring mode with ion mode switching. And the method was applied by analyzing phospholipids in the serum of coal workers' pneumoconiosis patients. Results: The 22 phospholipids showed good linear relationships in their respective concentration ranges and the correlation coefficients were higher than 0.990. The spiked recoveries of the 22 phospholipids were 81.03%-121.63% at the three spiked levels. The intra-assay were less than 14.52%, and the inter-assay were less than 15.00%. Conclusion: The method with the advantages of simplicity, stability and high sensitivity, and it can be used for the analysis of phospholipids in serum.

Rapid determination of acetaminophen in plasma by LC-MS/MS / 中华劳动卫生职业病杂志

Objective: To establish a method for the rapid determination of acetaminophen (APAP) in human plasma by LC-MS/MS. Methods: The plasma samples were extracted by methanol and acetonitrile (1: 1) and purified directly. C(18) column was used for sample separation. The mobile phase were methanol (5 mmol/L ammonium acetate) and water (5 mmol/L ammonium acetate). Samples were analyzed by LC MS/MS with the electrospray ionization multi reaction monitoring (MRM) mode. Results: The calibration curves of APAP was linear in the concentration range of 0~10 mg/L, the correlation coefficient (r) was greater than 0.999 0. The relative standard deviation within and between batches was less than 10%. The recovery rate were 96.81%~101.7%. The detection limit of the method was 0.1 μg/L and the lower limit of quantification was 0.3 μg/L. Conclusion: This method has strong specificity, high sensitivity and reliable determination results. It is suitable for the rapid analysis of clinical plasma samples.

Comparison of in vivo plasma pharmacokinetics and urine excretion of main components in Xihuang Formula in rats with precancerous lesions of breast cancer / 中国中药杂志

The UPLC-MS/MS was established for the determination of acetyl-11-keto-beta-boswellic acid(AKBA) and β-boswellic acid(β-BA), the main active components of Olibanum and Myrrha extracts in Xihuang Formula, in rat plasma and urine. The effects of compatibility on the pharmacokinetic behaviors of AKBA and β-BA in rats were investigated, and the differences in pharmacokinetic behaviors between healthy rats and rats with precancerous lesions of breast cancer were compared. The results showed that compared with RM-NH and RM-SH groups, the AUC_(0-t) and AUC_(0-∞) of β-BA increased(P<0.05 or P<0.01), T_(max) decreased(P<0.05 or P<0.01), and C_(max) increased(P<0.01) after compatibility. The trends of AKBA and β-BA were the same. Compared with RM-SH group, the T_(max) decreased(P<0.05), C_(max) increased(P<0.01), and the absorption rate increased in the normal group of Xihuang Formula. The results of urinary excretion showed that there was a decreasing trend in the urinary excretion rate and total urinary excretion of β-BA and AKBA after compatibility, but there was no statistical difference. Compared with normal group of Xihuang Formula, the AUC_(0-t) and AUC_(0-∞) of β-BA increased(P<0.05), T_(max) increased(P<0.05), and the clearance rate decreased in the breast precancerous lesion group. AUC_(0-t) and AUC_(0-∞) of AKBA showed an increasing trend, the in vivo retention time was prolonged, and the clearance rate was reduced, but there was no significant difference compared with the normal group. The cumulative urinary excretion and urinary excretion rate of β-BA and AKBA decreased under pathological conditions, indicating that pathological conditions could affect the in vivo process of β-BA and AKBA, and reduce their excretion in the form of prototype drugs, showing different pharmacokine-tic characteristics from normal physiological conditions. In this study, UPLC-MS/MS analysis method was established, which was sui-table for in vivo pharmacokinetic analysis of β-BA and AKBA. This study laid a foundation for the development of new dosage forms of Xihuang Formula.

Contamination status and exposure risk of mycotoxins in Coicis Semen / 中国中药杂志

By investigating the contamination status and predicting the exposure risk of mycotoxin in Coicis Semen, we aim to provide guidance for the safety supervision of Chinese medicinal materials and the formulation(revision) of mycotoxin limit standards. The content of 14 mycotoxins in the 100 Coicis Semen samples collected from five major markets of Chinese medicinal materials in China was determined by UPLC-MS/MS. The probability evaluation model based on Monte Carlo simulation method was established after Chi-square test and One-way ANOVA of the sample contamination data. Health risk assessment was performed on the basis of margin of exposure(MOE) and margin of safety(MOS). The results showed that zearalenone(ZEN), aflatoxin B_1(AFB_1), deoxynivalenol(DON), sterigmatocystin(ST), and aflatoxin B_2(AFB_2) in the Coicis Semen samples had the detection rates of 84%, 75%, 36%, 19%, and 18%, and the mean contamination levels of 117.42, 4.78, 61.16, 6.61, and 2.13 μg·kg~(-1), respectively. According to the limit standards in the Chinese Pharmacopoeia(2020 edition), AFB_1, AFs and ZEN exceeded the standards to certain extents, with the over-standard rates of 12.0%, 9.0%, and 6.0%, respectively. The exposure risks of Coicis Semen to AFB_1, AFB2, ST, DON, and ZEN were low, while 86% of the samples were contaminated with two or more toxins, which needs more attention. It is suggested that the research on the combined toxicity of different mycotoxins should be strengthened to accelerate the cumulative exposure assessment of mixed contaminations and the formulation(revision) of toxin limit standards.

Preparation of Huoluo Xiaoling gel plaster and its transdermal penetration in vitro / 中国中药杂志

Huoluo Xiaoling Dan is a classical prescription commonly used for blood circulation and pain relief in clinic with obvious effects. To make it directly treat lesion and improve the effect, this research optimized the preparation process of Huoluo Xiaoling gel paste and further evaluated its in vitro transdermal absorption performance, so as to provide a scientific basis for its development and utilization. Using primary viscosity, holding viscosity, and sensory score as evaluation indexes, the matrix amount of gel paste was determined by the single factor test and Box-Behnken response surface method. The ultra-performance liquid chromatography(UPLC) method was established to determine the content of eight active ingredients, including Danshensu, ferulic acid, salvianolic acid B, salvianolic acid A, ligustilide, tanshinone Ⅱ_A, 11-keto-β-boswellic(KBA), and 3-acetyl-11-keto-β-boswellic acid(AKBA). A mo-dified Franz diffusion cell method was used to evaluate and compare the absorption properties of the gel paste without volatile oil and with volatile oil microemulsion. The results showed that the optimal prescription for Huoluo Xiaoling gel paste matrix was NP700(1.35 g), glycerol(7.00 g), micropowder silica gel(1.25 g), sodium carboxymethyl cellulose(0.20 g), tartaric acid(0.06 g), and glyceryl aluminum(0.04 g). The mass fractions of eight active ingredients in the paste were successively 0.48, 0.014, 0.95, 0.39, 0.57, 0.055, 0.35, and 0.97 mg·g~(-1). The results of the in vitro transdermal absorption test showed that the addition of the volatile oil or the volatile oil microemulsion promoted the transdermal absorption of the active ingredients, and the law of drug penetration conformed to the zero equation or the Higuchi equation. The gel paste prepared by the optimal prescription has good appearance and adhesion, with no residue, and has the characteristics of skeletal slow-release preparation, which is easy to reduce the number of administration, la-ying a foundation for the development of new external dosage forms of Huoluo Xiaoling Dan.

Main components from cultivated and wild Nardostachyos Radix et Rhizoma by LC-MS and GC-MS / 中国中药杂志

In this study, ultra-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry(UPLC-Q-TOF-MS) and gas chromatography-mass spectrometry(GC-MS) were combined with non-targeted metabonomic analysis based on multivariate statistics analysis, and the content of five indicative components in nardosinone was determined and compared by UPLC. The main chemical components of Nardostachyos Radix et Rhizoma with imitative wild cultivation and wild Nardostachyos Radix et Rhizoma were comprehensively analyzed. The results of multivariate statistical analysis based on liquid chromatography-mass spectrometry(LC-MS) and GC-MS were consistent. G1 and G2 of the imitative wild cultivation group and G8-G19 of the wild group were clustered into category 1, while G7 of the wild group and G3-G6 of the imitative wild cultivation group were clustered into category 2. After removing the outlier data of G1, G2, and G7, G3-G6 of the imitative wild cultivation group were clustered into one category, and G8-G19 of the wild group were clustered into the other category. Twenty-six chemical components were identified according to the positive and negative ion modes detected by LC-MS. The content of five indicative components(VIP>1.5) was determined using UPLC, revealing that chlorogenic acid, isochlorogenic acid A, isochlorogenic acid C, linarin, nardosinone, and total content in the imitative wild cultivation group were 1.85, 1.52, 1.26, 0.90, 2.93, and 2.56 times those in the wild group, respectively. OPLS-DA based on GC-MS obtained 10 diffe-rential peaks. Among them, the relative content of α-humulene and aristolene in the imitative wild cultivation group were extremely significantly(P<0.01) and significantly(P<0.05) higher than that in the wild group, while the relative content of 7 components such as 5,6-epoxy-3-hydroxy-7-megastigmen-9-one, γ-eudesmol, and juniper camphor and 12-isopropyl-1,5,9-trimethyl-4,8,13-cyclotetrade-catriene-1,3-diol was extremely significantly(P<0.01) and significantly(P<0.05) lower than that in the wild group, respectively. Therefore, the main chemical components of the imitative wild cultivation group and wild group were basically the same. However, the content of non-volatile components in the imitative wild cultivation group was higher than that in the wild group, and the content of some volatile components was opposite. This study provides scientific data for the comprehensive evaluation of the quality of Nardostachyos Radix et Rhizoma with imitative wild cultivation and wild Nardostachyos Radix et Rhizoma.

Monoterpenoids from Paeoniae Radix Rubra based on UPLC-Q-TOF-MS / 中国中药杂志

The ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry(UPLC-Q-TOF-MS) was used to conduct the qualitative analysis of the monoterpene chemical components from Paeoniae Radix Rubra. Gradient elution was performed on C_(18) HD(2.1 mm×100 mm, 2.5 μm) column with a mobile phase of 0.1% formic acid(A) and acetonitrile(B). The flow rate was 0.4 mL·min~(-1) and the column temperature was 30 ℃. MS analysis was conducted in both positive and negative ionization modes using electrospray ionization(ESI) source. Qualitative Analysis 10.0 was used for data processing. The identification of chemical components was realized by the combination of standard compounds, fragmentation patterns, and mass spectra data reported in the literature. Forty-one monoterpenoids in Paeoniae Radix Rubra extract were identified. Among them, 8 compounds were reported in Paeoniae Radix Rubra for the first time and 1 was presumed to be the new compound 5″-O-methyl-galloylpaeoniflorin or its positional isomer. The method in this study realizes the rapid identification of monoterpenoids from Paeoniae Radix Rubra and provides a material and scientific basis for quality control and further study on the pharmaceutical effect of Paeoniae Radix Rubra.

Eleven new sesquiterpenoids from peeled stems of Syringa pinnatifolia / 中国中药杂志

The peeled stems of Syringa pinnatifolia(SP) is a representative Mongolian folk medicine with the effects of anti-depression, heat clearance, pain relief, and respiration improvement. It has been clinically used for the treatment of coronary heart disease, insomnia, asthma, and other cardiopulmonary diseases. As part of the systematic study on pharmacological substances of SP, 11 new sesquiterpenoids were isolated from the terpene-containing fractions of the ethanol extract of SP by liquid chromatography-mass spectrometry(LC-MS) and proton nuclear magnetic resonance(~1H-NMR) guided isolation methods. The planar structures of the sesquiterpenoids were identified by MS, 1D NMR, and 2D NMR data analysis, and were named pinnatanoids C and D(1 and 2), and alashanoids T-ZI(3-11), respectively. The structure types of the sesquiterpenoids included pinnatane, humulane, seco-humulane, guaiane, carryophyllane, seco-erimolphane, isodaucane, and other types. However, limited to the low content of compounds, the existence of multiple chiral centers, the flexibility of the structure, or lack of ultraviolet absorption, the stereoscopic configuration remained unresolved. The discovery of various sesquiterpenoids enriches the understanding of the chemical composition of the genus and species and provides references for further analysis of pharmacological substances of SP.

Anti-depression targets and mechanism study of Kaixin San / 中国中药杂志

This study identified the anti-depression targets of Kaixin San(KXS) in the brain tissue with "target fishing" strategy, and explored the target-associated pharmacological signaling pathways to reveal the anti-depression molecular mechanism of KXS. The Balb/c mouse model of depression was established by chronic unpredictable mild stress(CUMS) and the anti-depression effect of KXS was evaluated by forced swimming test and sucrose preference test. KXS active components were bonded to the benzophenone-modified magnetic nanoparticles by photocrosslinking reaction for capturing target proteins from cortex, thalamus and hippocampus of depressive mice. The target proteins were identified by liquid chromatography-mass spectrometry/mass spectrometry(LC-MS/MS). The enrichment analysis on signaling pathways was performed by Cytoscape. The potential biological functions of targets were verified by immunohistochemistry and Western blot assay. The results showed that KXS significantly improved the behavioral indexes. There were 64, 91, and 44 potential targets of KXS identified in cortex, thalamus, and hippocampus, respectively, according to the target identification experiment. The functions of these targets were mainly associated with vasopressin-regulated water reabsorption, salmonella infection, thyroid hormone synthesis, and other signaling pathways. Besides, the results of immunohistochemistry and Western blot showed that KXS up-regulated the expressions of argipressine(AVP) in the cortex, heat shock protein 60(HSP60), cytochrome C oxidase 4(COX4), and thyrotropin-releasing hormone(TRH) in the thalamus, and down-regulated the expressions of tumor necrosis factor-α(TNF-α) and nuclear factor kappa B(NF-κB) p65 in the thalamus. Therefore, KXS may exert anti-depression effect through regulating vasopressin signaling pathway in the cortex and inflammation, energy metabolism, and thyroid hormone signaling pathways in the thalamus, and the effect of KXS on hippocampus is not significant.

Determination of 10 mycotoxins in Hippophae Fructus medicinal and edible products by ultra-performance liquid chromatography- tandem mass spectrometry / 中国中药杂志

An analytical method for 10 mycotoxins in Hippophae Fructus medicinal and edible products was established in this study, and the contamination of their mycotoxins was analyzed. First of all, the mixed reference solution of ten mycotoxins such as aflatoxin, ochratoxin, zearalenone, and dexoynivalenol was selected as the control, and the Hippophae Fructus medicinal and edible products were prepared. Secondly, based on the ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) technology, 10 mycotoxins in Hippophae Fructus medicinal and edible products were quantitatively investigated and their content was determined. Finally, the contamination of mycotoxins was analyzed and evaluated. The optimal analysis conditions were determined, and the methodological inspection results showed that the 10 mycotoxins established a good linear relationship(r>0.99). The method had good repeatability, test sample specificity, stability, and instrument precision. The average recovery rates of 10 mycotoxins in Hippophae Fructus medicinal products, edible solids, and edible liquids were 90.31%-109.4%, 87.86%-107.8%, and 85.61%-109.1%, respectively. Relative standard deviation(RSD) values were 0.22%-10%, 0.75%-13%, and 0.84%-8.5%, repsectively. Based on UPLC-MS/MS technology, the simultaneous determination method for the limits of 10 mycotoxins established in this study has fast detection speed, less matrix interference, high sensitivity, and accurate results, which is suitable for the limit examination of 10 mycoto-xins in Hippophae Fructus medicinal and edible products.

Formation and characteristics of polystyrene nanoplastic-plant protein corona / 生物工程学报

To investigate the formation of polystyrene nanoplastic-plant protein corona and its potential impact on plants, three differently modified polystyrene nanoplastics with an average particle size of 200 nm were taken to interact with the leaf proteins of Impatiens hawkeri for 2 h, 4 h, 8 h, 16 h, 24 h, and 36 h, respectively. The morphological changes were observed by scanning electron microscopy (SEM), the surface roughness was determined by atomic force microscopy (AFM), the hydrated particle size and zeta potential were determined by nanoparticle size and zeta potential analyzer, and the protein composition of the protein corona was identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The proteins were classified in terms of biological processes, cellular components, and molecular functions to study the adsorption selection of nanoplastics to proteins, investigate the formation and characteristics of polystyrene nanoplastic-plant protein corona and predict the potential impact of protein corona on plants. The results showed that the morphological changes of the nanoplastics became clearer as the reaction time extends, as evidenced by the increase in size and roughness and the enhancement of stability, thus demonstrating the formation of protein corona. In addition, the transformation rate from soft to hard protein corona was basically the same for the three polystyrene nanoplastics in the formation of protein corona with leaf proteins under the same protein concentration conditions. Moreover, in the reaction with leaf proteins, the selective adsorption of the three nanoplastics to proteins with different isoelectric points and molecular weights differed, and the particle size and stability of the final formed protein corona also differed. Since a large portion of the protein fraction in protein corona is involved in photosynthesis, it is hypothesized that the formation of the protein corona may affect photosynthesis in I. hawkeri.

Study on the dynamic variation of the secondary metabolites in Viscum coloratum using targeted metabolomics / 中国天然药物

Viscum coloratum (Kom.) Nakai is a well-known medicinal plant. However, the optimal harvest time for V. coloratum is unknown. Few studies were performed to analyze compound variation during storage and to improve post-harvest quality control. Our study aimed to comprehensively evaluate the quality of V. coloratum in different growth stages, and determine the dynamic variation of metabolites. Ultra-performance liquid chromatography tandem mass spectrometry was used to quantify 29 compounds in V. coloratum harvested in six growth periods, and the associated biosynthetic pathways were explored. The accumulation of different types of compounds were analyzed based on their synthesis pathways. Grey relational analysis was used to evaluate the quality of V. coloratum across different months. The compound variation during storage was analyzed by a high-temperature high-humidity accelerated test. The results showed that the quality of V. coloratum was the hightest in March, followed by November, and became the lowest in July. During storage, compounds in downstream steps of the biosynthesis pathway were first degraded to produce the upstream compounds and some low-molecular-weight organic acids, leading to an increase followed by a decrease in the content of some compounds, and resulted in a large gap during the degradation time course among different compounds. Due to the rapid rate and large degree of degradation, five compounds were tentatively designated as "early warning components" for quality control. This report provides reference for better understanding the biosynthesis and degradation of metabolites in V. coloratum and lays a theoretical foundation for rational application of V. coloratum and better quality control of V. coloratum during storage.

Analysis of Forty-Two Psychoactive Substances in a Single Hair by Micro-Segmental Technique / 法医学杂志

OBJECTIVES@#To establish an LC-MS/MS method based on single hair micro-segmental technique, and verify the detection of 42 psychoactive substances in 0.4 mm hair segments.@*METHODS@#Each piece of single hair was cut into 0.4 mm segments and extracted by sonication and the segments were immersed in dithiothreitol-containing extraction medium. Mobile phase A was the aqueous solution containing 20 mmol/L ammonium acetate, 0.1% formic acid, and 5% acetonitrile. Mobile phase B was acetonitrile. An electrospray ionization source in positive ion mode was used for data acquisition in multiple reaction monitoring (MRM) mode.@*RESULTS@#The 42 psychoactive substances in hair had a good linear relationship within their respective linear ranges (r>0.99), the limits of detection were 0.2-10 pg/mm, the limits of quantification were 0.5-20 pg/mm, the intra-day and inter-day precisions were 1.5%-12.7%, the intra-day and inter-day accuracies were 86.5%-109.2%, the recovery rates were 68.1%-98.2%, and the matrix effects were 71.3%-111.7%. The method was applied to hair samples collected from one volunteer at 28 d after a single dose of zolpidem, with zolpidem detected in 5 hairs was 1.08-1.60 cm near the root tip, and the concentration range was 0.62-20.5 pg/mm.@*CONCLUSIONS@#The micro-segmental technique of single hair analysis can be applied to the investigation of drug-facilitated sexual assault cases.

Content determination of seven active components of Eucommiae Cortex in aortic vascular endothelial cells of spontaneously hypertensive rats by UPLC-MS/MS / 中国中药杂志

In the present study, the contents of seven active components [genipinic acid(GA), protocatechuic acid(PCA), neochlorogenic acid(NCA), chlorogenic acid(CA), cryptochlorogenic acid(CCA),(+)-pinoresinol di-O-β-D-glucopyranosid(PDG), and(+)-pinoresinol 4'-O-β-D-glucopyranoside(PG)] of Eucommiae Cortex in aortic vascular endothelial cells of spontaneously hypertensive rats(SHR) were simultaneously determined by ultra-high liquid chromatography-triple quadrupole mass spectrometry(UPLC-MS/MS). The qualified SHR models were selected. The primary aortic endothelial cells(VECs) of rats were separated and cultured by ligation and adherence, followed by subculture. After successful identification, an UPLC-MS/MS method for simultaneously determining the contents of GA, PCA, NCA, CA, CCA, PDG, PG in seven components of Eucommiae Cortex in VECs was established, including specificity, linearity, matrix effect, recovery, accuracy, precision and stability. The established method had the lo-west limit of quantification of 0.97-4.95 μg·L~(-1), accuracy of 87.26%-109.6%, extraction recovery of 89.23%-105.3%, matrix effect of 85.86%-106.2%, and stability of 86.00%-112.5%. Therefore, the established accurate UPLC-MS/MS method could rapidly and simultaneously determine the contents of the seven active components of Eucommiae Cortex in VECs of SHRs, which provided a refe-rence for the study of cellular pharmacokinetics of active components of Eucommiae Cortex extract.