Tolerability of glutamine supplementation in older adults: a double-blind placebo-controlled randomized clinical trial

In this double-blind placebo-controlled randomized investigation, we assessed the tolerability of glutamine in older adults recruited from three daycare centers. The relevance of studying glutamine supplementation in elderly patients lies in its potential to provide a well-tolerated intervention. Glutamine, a crucial amino acid, plays a vital role in various physiological processes, including immune function and protein synthesis. Understanding its impact on older adults is essential, given the potential implications for their health and well-being. Participants received a daily dose of 12.4 g of oral effervescent glutamine (EGln group) or maltodextrin (placebo group) for 60 days. Fifteen patients from each group completed the study. The mean ages were 77.0±9.1 and 79.0±6.9 years for the EGln and placebo groups, respectively. We evaluated body mass index, aminogram, hemogram, plasma levels of glucose, prealbumin, albumin, urea, creatinine, uric acid, C-reactive protein, vitamin D, calcium, sodium, potassium, and the plasma activities of aspartate aminotransferase and alanine aminotransferase. Notably, we quantified a broad array of inflammatory markers and growth factors providing a holistic understanding of the potential effects of glutamine supplementation. The results demonstrated that oral glutamine did not induce significant changes in any evaluated parameters, and no adverse effects were reported. This finding suggested that the dosage of glutamine used in this study was well-tolerated and safe. This information contributes to the broader understanding of glutamine supplementation, emphasizing its safety and supporting its potential as a viable intervention for maintaining health in aging individuals.

Content determination of seventeen amino acids in Gualoupi Injection and its intermediates and research on their change laws / 中成药

AIM To determine the contents of aspartic acid,glutamic acid,serine,glycine,threonine,citrulline,arginine,alanine,γ-amino-butyric acid,tyrosine,valine,phenlalanine,isoleucine,ornithine,leucine,lysine and proline in Gualoupi Injection and its intermediates,and to analyze their change laws.METHODS The OPA-FMOC online derivatization analysis was performed on a 45℃ thermostatic Waters XBridge C18 column(4.6 mm×100 mm,3.5 μm),with the mobile phase comprising of phosphate buffer solution-[methanol-acetonitrile-water(45 : 45 : 10)]flowing at 1 mL/min in a gradient elution manner,and the detection wavelengths were set at 262,338 nm.Principal component analysis and heatmap analysis were adopted in chemical pattern recognition for the corresponding intermediates in ten processes of six batches of samples.RESULTS Seventeen amino acids showed good linear relationships within their own ranges(R2>0.998 0),whose average recoveries were 83.4％-119.5％with the RSDs of 0.91％-7.94％.Different batches of samples in the same process were clustered,and the corresponding intermediates in different processed were clustered into three groups.Alcohol precipitation and cation exchange column demonstrated the biggest influences on amino acid composition.CONCLUSION This experiment can provide important references for the critical factors on quality control of Gualoupi Injection,thus ensure the stability and uniformity of final product.

Determination of amino acids in rat serum based on an UPLC method with pre-column derivatization of PITC / 中国生物制品学杂志

@#Objective To develop an ultra performance liquid chromatography(UPLC)method for simultaneous determination of 19 amino acids in rat serum by employing the pre-column derivatization of phenyl isothiocyanate(PITC),verify and preliminarily apply the method.Methods The analysis was performed on an ACQUITY UPLC~?BEH C_(18) column(2.1mm×100 mm,1.7 μm) by using 0.1 mol/L sodium acetate buffer solution-acetonitrile as mobile phase at the flow rate of 0.3 mL/min in gradient elution.The column temperature was fixed at 52 ℃,and the detection wavelength was 254 nm.The specificity,linearity,precision,stability and accuracy of the method were verified based on the optimized chromatographic conditions and preparation method of sample solution,and the contents of 19 amino acids in rat serum were determined by using the developed method.Results All 19 amino acids in rat serum were separated well within 10 min,and the blank derivatization solvent and internal standard compounds had no interference with the analysis of amino acids.All the components exhibited good linear correlation in the given range(r ≥ 0.998 0),the limit of detection was 0.004 6-0.186 5 μg/mL,and the limit of quantitation was 0.013 9-0.559 6 μg/mL.The RSDs of precision and stability tests were all less than 4%.The average spike recoveries ranged from 90% to 110% and the RSDs were less than 5%.The contents of amino acids in rat serum ranged from 4.837 to 110.233 μg/mL.Conclusion The developed method is sensitive,simple and feasible,which is suitable for the analysis of amino acids in rat serum.

Research progress in the metabolism of branched-chain amino acids and obesity related insulin resistance / 中国糖尿病杂志

Obese patients may have abnormal metabolism of branched-chain amino acids(BCAA).Elevated levels of BCAA can lead to insulin resistance(IR)through various mechanisms,which may make it a sensitive indicator for predicting the occurrence of diabetes mellitus.This article reviews the research progress on the correlation between BCAA metabolism,obesity and IR.

Analysis on Quality of Sojae Semen Praeparatum Based on Traditional Quality Evaluation / 中国实验方剂学杂志

ObjectiveBased on the quality evaluation experience of "it is better to have a fragrant and strong aroma" summarized by materia medica of past dynasties， the chemical components of Sojae Semen Nigrum（SSN） and Sojae Semen Praeparatum（SSP） were systematically compared and analyzed， and the main fermentation products in different fermentation time were quantitatively analyzed， so as to clarify the transformation law of internal components in the processing process and provide scientific basis for the modern quality control of SSP. MethodUltra performance liquid chromatography-quadrupole tandem time-of-flight mass spectrometry（UPLC-Q-TOF-MS） was used for the structural identification of the chemical constituents of SSN and SSP， and with the aid of Progenesis QI v2.3 software， the negative ion mode was employed for principal component analysis（PCA） pattern recognition， and the data were analyzed with the aid of orthogonal partial least squares-discriminant analysis（OPLS-DA） for two-dimensional data to obtain S-plot， and components with |P|>0.1 were selected as the differential constituents. The contents of isoflavonoids in SSP during fermentation was determined by UPLC， and the samples were taken every 8 h in the pre-fermentation period and every 2 d in the post-fermentation period， and the dynamic changes of isoflavonoid contents in different fermentation stages were analyzed. The contents of amino acids and nucleosides in SSP and SSN from different fermentation stages were quantitatively analyzed by phenyl isothiocyanate（PITC） pre-column derivatization and high performance liquid chromatography（HPLC） gradient elution， and the contribution of flavor substances to the "delicious" taste of SSP was discussed by taste intensity value（TAV）. ResultA total of 19 kinds of differential components were screened out， mainly soybean saponins and isoflavones， and their contents decreased significantly or even disappeared after fermentation. In the pre-fermentation process of SSP， glycoside bond hydrolysis mainly occurred， and isoflavone glycosides in SSN were degraded and converted into the corresponding aglycones， the content of flavor substances such as amino acids increased gradually. In the post-fermentation process， protein degradation mainly occurred， after 8 d of post-fermentation， the content of isoflavones was basically stable， while the total content of amino acids increased by 8-40 times on average. Different amino acids form the special flavor of SSP， such as the TAV of glutamate is always ahead of other flavor substances， and sweet substances such as alanine and valine have made relatively great contributions to SSP. ConclusionBased on the law of constituent transformation， combined with the traditional evaluation index of "fragrant and strong"， it is difficult to control the fermentation degree of SSP by the existing standards in the 2020 edition of Chinese Pharmacopoeia. It is suggested that description of the characteristics of SSP be refined and changed to "fragrant， delicious and slightly sweet"， and at the same time， the post-fermentation index compounds such as glutamic acid， alanine and valine should be added as the quality control indicators of SSP， so as to standardize the production process and improve the quality of SSP.

Mechanism of amino acid metabolism in nonalcoholic fatty liver disease / 临床肝胆病杂志

Nonalcoholic fatty liver disease （NAFLD） is one of the most prevalent chronic liver diseases in the world， affecting about one quarter of the global population， and it is estimated that NAFLD will become the main indication for liver transplantation by 2030. NAFLD can lead to significant abnormalities in the levels of a variety of amino acids including branched-chain amino acids， thereby promoting the development and progression of NAFLD. These results suggest that in addition to glucose and lipid metabolism， amino acid metabolism also plays an important role in the progression of NAFLD. In order to systematically understand the role and mechanism of amino acid metabolism in NAFLD， this article reviews the research advances in amino acid metabolism in NAFLD. This article aims to explore the role and mechanism of amino acid metabolism in the progression of NAFLD， so as to provide ideas and a theoretical basis for clinical prevention and treatment.

Performance evaluation of the commercial aquafeeds available in the market of Pakistan on Channa marulius (Sole) / Avaliação de desempenho dos alimentos aquáticos comerciais disponíveis no mercado do Paquistão em Channa marulius (Sole)

Abstract The present study aimed to determine the effect of different levels of protein on the growth, body composition, amino acid profile and serology of Channa marulius fingerlings. The experiment was conducted in ten happas installed in earthen ponds, each stocked with 10 fishes for 90 days. Four commercial fish feeds having 25%, 30%, 32% and 40% crude protein (CP) levels were fed to fish at 3% of their wet body weight three times a day. The results of the study revealed that highest weight gain, feed conversion ratio and survival rate were observed in 30% protein feed. Meanwhile, moisture content was higher in fish fed with 30% CP feed while highest crude protein was recorded in 40% CP fed fish. Lowest fat content was observed in 32% CP feed. Amino acid profile of fish revealed better results in 30% CP feed. Total protein, glucose and globulin were also highest in fish feeding 30% CP feed, while albumin was highest in 40% CP feed. It is concluded that 30% CP feed showed better results in terms of growth, amino acid profile and serological parameters without effecting fish body composition.

Resumo O presente estudo teve como objetivo determinar o efeito de diferentes níveis de proteína sobre o crescimento, composição corporal, perfil de aminoácidos e sorologia de alevinos de Channa marulius. O experimento foi conduzido em dez happas instalados em tanques de terra, cada um abastecido com 10 peixes, por 90 dias. Quatro alimentos para peixes comerciais com níveis de 25%, 30%, 32% e 40% de proteína bruta (PB) foram dados aos peixes com 3% de seu peso corporal úmido três vezes ao dia. Os resultados do estudo revelaram que maior ganho de peso, taxa de conversão alimentar e taxa de sobrevivência foram observados em 30% de proteína alimentar. Enquanto isso, o conteúdo de umidade foi maior em peixes alimentados com 30% de PB, enquanto a proteína bruta mais alta foi registrada em peixes alimentados com 40% de PB. O menor conteúdo de gordura foi observado em rações com 32% de PB. O perfil de aminoácidos dos peixes revelou melhores resultados na ração com 30% de PB. Proteína total, glicose e globulina também foram maiores em peixes alimentados com ração com 30% de PB, enquanto a albumina foi mais alta com 40% de PB. Conclui-se que a ração com 30% de PB apresentou melhores resultados em termos de crescimento, perfil de aminoácidos e parâmetros sorológicos sem afetar a composição corporal dos peixes.

Performance evaluation of the commercial aquafeeds available in the market of Pakistan on Channa marulius (Sole)

Abstract The present study aimed to determine the effect of different levels of protein on the growth, body composition, amino acid profile and serology of Channa marulius fingerlings. The experiment was conducted in ten happas installed in earthen ponds, each stocked with 10 fishes for 90 days. Four commercial fish feeds having 25%, 30%, 32% and 40% crude protein (CP) levels were fed to fish at 3% of their wet body weight three times a day. The results of the study revealed that highest weight gain, feed conversion ratio and survival rate were observed in 30% protein feed. Meanwhile, moisture content was higher in fish fed with 30% CP feed while highest crude protein was recorded in 40% CP fed fish. Lowest fat content was observed in 32% CP feed. Amino acid profile of fish revealed better results in 30% CP feed. Total protein, glucose and globulin were also highest in fish feeding 30% CP feed, while albumin was highest in 40% CP feed. It is concluded that 30% CP feed showed better results in terms of growth, amino acid profile and serological parameters without effecting fish body composition.

Resumo O presente estudo teve como objetivo determinar o efeito de diferentes níveis de proteína sobre o crescimento, composição corporal, perfil de aminoácidos e sorologia de alevinos de Channa marulius. O experimento foi conduzido em dez happas instalados em tanques de terra, cada um abastecido com 10 peixes, por 90 dias. Quatro alimentos para peixes comerciais com níveis de 25%, 30%, 32% e 40% de proteína bruta (PB) foram dados aos peixes com 3% de seu peso corporal úmido três vezes ao dia. Os resultados do estudo revelaram que maior ganho de peso, taxa de conversão alimentar e taxa de sobrevivência foram observados em 30% de proteína alimentar. Enquanto isso, o conteúdo de umidade foi maior em peixes alimentados com 30% de PB, enquanto a proteína bruta mais alta foi registrada em peixes alimentados com 40% de PB. O menor conteúdo de gordura foi observado em rações com 32% de PB. O perfil de aminoácidos dos peixes revelou melhores resultados na ração com 30% de PB. Proteína total, glicose e globulina também foram maiores em peixes alimentados com ração com 30% de PB, enquanto a albumina foi mais alta com 40% de PB. Conclui-se que a ração com 30% de PB apresentou melhores resultados em termos de crescimento, perfil de aminoácidos e parâmetros sorológicos sem afetar a composição corporal dos peixes.

Direct spectrofluorimetric methods as alternatives to compendial ones used for the quality control of biopharmaceuticals: development, validation and application

Abstract A simple, rapid, precise, accurate and sustainable spectrofluorimetric method (SFM) was developed, validated and applied for the determination of 4-aminobenzoic acid and aromatic amino acids (phenylalanine, tryptophan and tyrosine). These compounds are used in biopharmaceutical formulations and therefore must be analyzed by quality control laboratories to meet the criteria established in pharmacopoeias. In general, potentiometric titration (PT) is described in the compendia as the official analytical technique. However, this method showed low sensitivity and selectivity, and moreover was performed with a non-aqueous solvent (acetic acid), which led to higher consumption of reagents and consequently to the formation of residues. Therefore, the SFM was developed in aqueous medium at pH 7.2 using phosphate buffer. It was successfully validated according to the ICH guidelines and showed good linearity range (r>0.999), specificity, accuracy and precision (within and between days) and robustness. The test results were compared between the SFM and PT using raw material samples, while according to the F- and t-tests at 95% confidence level, no statistical difference was found between the methods

Cytotoxic and microbial studies of mixed metal complexes

Breast cancer and its treatment have become a prominent and challenging problem today. The increasing multidrug resistance to microbial pathogens is the root cause of breast cancer. Women suffering from cancer showed high levels of E. coli and S. aureus. In the last few decades, there has been a considerable need in the medical field for the discovery of new compounds endowed with antimicrobial activity, despite the fact that several antibiotics and chemotherapy drugs are currently accessible. Substantial research was conducted, particularly on transition complexes as metal-based drugs in pharmacological applications to provide therapeutic options. The synthesis, characterization, antibacterial activity, and cytotoxic activity of copper complexes with specific ligands of amino acids such as tyrosine and arginine are discussed in this work.

The Efficacy and Safety of a Combination of Amino Acids, Vitamins and Probiotics in PROM and PPROM

The prevalence and severity of prelabor rupture of the membranes (PROM)/preterm PROM (PPROM) are a worldwide public health concern. PROM is the result of a cascade of events involving matrix metalloproteinase (MMP)-9, tissue inhibitor of metalloproteinases 1 (TIMP1), cytokines and proapoptotic genes, which is initiated by several factors such as infection, genotoxic agents or some unknown etiology. In PROM, there is an increased expression and activation of MMP-2, MMP-3 and MMP-9 and a reduction of TIMP1. p53 and tumor necrosis factor (TNF)-? mediate the major apoptotic pathway of PROM. p53 can transactivate some MMP genes, resulting in the overexpression of MMPs. This leads to apoptosis. MMP-2 and MMP-9 degrades type-IV collagen, which is the major structural component of chorioamnion. Understanding the fundamental pathology at the molecular level, it appears necessary to adjust the biologically protective mechanism to prevent spontaneous preterm labor. Our findings show that the novel combination of arginine, ascorbic acid, folic acid, glutamine, glutathione, thiamine, lactic acid bacillus spores, vitamin E acetate and pyridoxine is safe and effectively prevents PROM and PPROM (97% patients) and prolongs pregnancy term.

Safety and Efficacy of a Combination of Amino Acids in Insufficient Lactating Mothers

Milk production of the mammary gland is mainly determined by the milk synthesis and proliferation abilities of mammary epithelial cells (MECs). The availability of amino acids is critical for the production of milk. Amino acids enhance milk protein synthesis and mammary gland development through the mechanistic target of rapamycin (mTOR) pathway. Taurine enhances lactation by increasing prolactin secretion. Vitamins such as Thiamine and Pyridoxine are essential for maintaining and growing maternal and child health. However, there is a paucity of data regarding the safety and efficacy of amino acids and vitamins combination in lactating mothers with insufficient lactation. Hence, a prospective study was conducted to assess the safety and efficacy of a novel amino acids and vitamins combination. The results showed that with the intervention of this combination, 62% of participants showed onset of lactation within 45 minutes to 2 hours. The study suggests clinicians should consider this novel combination to improve lactation in insufficient lactating mothers

Blind docking of 4-Amino-7-Chloroquinoline analogs as potential dengue virus protease inhibitor using CB Dock a web server-Supplemenntary data

Currently, there is no approved drug to combat dengue. Various quinoline derivatives are known for potential antimalarial, antiviral activities, etc. In the present work docking between 4-Amino-7-Chloroquinoline analogs was performed with dengue virus NS2B/NS3 protease using CB dock, a web server. Lys74, Ile165, Val147, Asn152, Asn167, Trp83 and Leu149 amino acid residues were found to be in contact with designed 4-Amino-7-Chloroquinoline analogs. Different modes of binding like hydrogen bonding, hydrophobic interactions, etc with designed compounds improve potential anti-dengue characteristics in silico. ADME results are in acceptable range.

Blind docking of 4-Amino-7-Chloroquinoline analogs as potential dengue virus protease inhibitor using CB Dock a web server

Currently, there is no approved drug to combat dengue. Various quinoline derivatives are known for potential antimalarial, antiviral activities, etc. In the present work docking between 4-Amino-7-Chloroquinoline analogs was performed with dengue virus NS2B/NS3 protease using CB dock, a web server. Lys74, Ile165, Val147, Asn152, Asn167, Trp83 and Leu149 amino acid residues were found to be in contact with designed 4-Amino-7-Chloroquinoline analogs. Different modes of binding like hydrogen bonding, hydrophobic interactions, etc with designed compounds improve potential anti-dengue characteristics in silico. ADME results are in acceptable range.

Assay of amino acids in leaves of Eucommia ulmoides under arbor forest mode and leaf-oriented cultivation mode by pre-column derivatization HPLC / 中国中药杂志

This study aims to develop the pre-column derivatization high performance liquid chromatography(HPLC) method for the determination of 16 kinds of amino acids in Eucommia ulmoides leaves, and compare the content of amino acids in the leaves harvested at different time and under leaf-oriented cultivation mode(LCM) and arbor forest mode(AFM). The HPLC conditions are as below: phenyl isothiocyanate(PITC) as pre-column derivatization agent, Agilent ZORBAX C_(18 )column(4.6 mm×250 mm, 5 μm), mobile phase A of acetonitrile-water(80∶20), mobile phase B of 0.1 mol·L~(-1) sodium acetate solution-acetonitrile(94∶6), gradient elution, flow rate of 1.0 mL·min~(-1), injection volume of 5 μL, column temperature of 40 ℃, and detection wavelength of 254 nm. The HPLC profile indicated well separation of 16 kinds of amino acids and the amino acid content in E. ulmoides leaves was up to 16.26%. In addition, the amino acid content in leaves of E. ulmoides under LCM was higher than under AFM. The amino acid content varied with the harvesting time. Through orthogonal partial least squares discriminant analysis, the amino acids of E. ulmoides under LCM and AFM were compared, which can distinguish the leaves under LCM from those under AFM. Principal component analysis was applied to comprehensively score the amino acids of E. ulmoides leaves. The results showed that the score of leaves under LCM was higher than that under AFM. Nutritional evaluation results indicated that the proteins in E. ulmoides leaves belonged to high-quality vegetable proteins. The established method for the determination of amino acid content is reliable. With the amino acid content as index, the leaf quality of E. ulmoides under LCM is better than that under AFM. This study lays a theoretical basis for the promotion of LCM for E. ulmoides and the development of medicinal and edible products from E. ulmoides leaves.

Analysis of plasma amino acid profiles in adolescents and adults with atopic dermatitis / 中华皮肤科杂志

Objective:To analyze changes in plasma amino acid profiles in adolescents and adults with atopic dermatitis (AD) by targeted metabolomics, to further analyze differences in plasma amino acid profiles between AD patients with elevated total IgE levels and those with normal total IgE levels, as well as between AD patients with and without allergic rhinitis, and to explore the pathogenesis of AD from the perspective of metabolic pathways.Methods:From December 2021 to June 2022, 40 AD patients aged > 12 years were collected as research subjects from the Department of Dermatology, the First Affiliated Hospital of Jinzhou Medical University, and 30 healthy checkup examinees served as a control group at the same time. Plasma samples were obtained from the subjects, and high-performance liquid chromatography-mass spectrometry was performed to detect levels of metabolites in the plasma samples. Principal component analysis (PCA) and orthogonal partial least square-discriminant analysis (OPLS-DA) were carried out to analyze data and screen out differential metabolites with the variable weight value (VIP) of the first principal component being > 1 in the OPLS-DA model and the P value being < 0.05 in the t test. Possible abnormal metabolic pathways were analyzed using MetaboAnalyst 5.0 software, and differential metabolic pathways were defined as those with an impact value of > 0.1 and a P value of < 0.05. Results:PCA and OPLS-DA model analysis showed that metabolites were well differentiated among the groups, and differential metabolites and metabolic pathways were screened out. Concretely speaking, 12 differential metabolites and 8 differential metabolic pathways were identified by comparing the AD group with the control group, among which differential metabolites included arginine (metabolic levels: 28.257 ± 11.517 μmol/L vs. 21.038 ± 8.500 μmol/L, VIP = 1.32, P = 0.001), ornithine (47.597 ± 18.158 μmol/L vs. 36.937 ± 5.813 μmol/L, VIP = 1.26, P < 0.001) and histidine (78.322 ± 14.971 μmol/L vs. 100.694 ± 32.419 μmol/L, VIP = 1.33, P < 0.001), and differential metabolic pathways included arginine biosynthesis (impact = 0.482, P < 0.001) and histidine metabolism (impact = 0.221, P < 0.001). Comparisons between the AD group with elevated IgE levels and those with normal IgE levels showed 5 differential metabolites and 3 differential metabolic pathways, among which differential metabolites included lysine (313.998 ± 61.252 μmol/L vs. 285.330 ± 58.388 μmol/L, VIP = 2.25, P < 0.001) and glycine (200.807 ± 53.320 μmol/L vs. 187.056 ± 50.941 μmol/L, VIP = 1.40, P = 0.014), and differential metabolic pathways included the glyoxylate and dicarboxylate metabolic pathway (impact = 0.105, P = 0.001) ; by comparing the AD group with and without allergic rhinitis, 6 differential metabolites and 3 differential metabolic pathways were identified, among which the arginine biosynthesis metabolic pathway was highlighted (impact = 0.116, P < 0.001) . Conclusion:The plasma amino acid metabolites in adolescents and adults with AD were different from those in healthy controls, and elevated plasma levels of arginine and ornithine and decreased plasma level of histidine may be involved in the pathogenesis of AD; increased plasma levels of lysine and glycine were associated with AD with elevated IgE levels; the arginine biosynthetic metabolic pathway was related to AD complicated by allergic rhinitis.

Research trends on the effects of different nutritional components on depression disorder / 中国神经精神疾病杂志

Depression disorder(DD)is one of the major mental health problems worldwide,and special nutrients such as amino acids,vitamins,fatty acids,probiotics,etc.can affect the emotional state and disease prognosis of DD patients.Amino acids such as tryptophan and S-adenosylmethionine have been shown to improve stress levels in DD patients through various mechanisms,including vitamin B and vitamin C,while unsaturated fatty acids and probiotics have also been shown to have the same effect.This article reviews the mechanisms by which these nutrients improve DD,with the aim of providing new clues for treatment of DD.

Metabolomics study on occupational acute methyl acetate poisoning using patient plasma / 中国职业医学

Objective: To investigate the specificity of endogenous metabolic profile in plasma of patients with occupational acute methyl acetate poisoning using non-targeted metabolomics. Methods: A total of six patients with occupational acute methyl acetate poisoning were selected as the poisoning group, while 10 healthy workers without occupational exposure history of chemical hazards in the same industry were selected as the control group using the judgment sampling method. Metabolites in patient plasma of the two groups were detected using ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry, and non-targeted metabolomics analysis was performed. Principal component analysis and partial least squares discriminant analysis were used to identify differential metabolites and analyze their metabolic pathways. Results: There were significant differences in metabolite profiles in patient plasma between poisoning group and control group. A total of 195 differentially expressed metabolites were screened in plasma of patients in poisoning group, including 119 upregulated and 76 downregulated metabolites. Lipid substances (lipids and lipid-like molecules) accounted for the highest proportion (21.5%). The differential metabolites of poisoning group were related to folate biosynthesis, amino acid metabolism, pyrimidine metabolism, sphingolipid biosynthesis and other metabolic pathways in plasma compared with the control group (all P<0.05). Conclusion: Occupational acute methyl acetate poisoning affects metabolism of the body. The folic acid biosynthesis, amino acid and lipid metabolism and other pathways may be involved in the occurrence and development of poisoning.

Neurotoxicity mechanism of aconitine in HT22 cells studied by microfluidic chip-mass spectrometry / 药物分析学报

Aconitine,a common and main toxic component of Aconitum,is toxic to the central nervous system.However,the mechanism of aconitine neurotoxicity is not yet clear.In this work,we had the hypothesis that excitatory amino acids can trigger excitotoxicity as a pointcut to explore the mechanism of neurotoxicity induced by aconitine.HT22 cells were simulated by aconitine and the changes of target cell metabolites were real-time online investigated based on a microfluidic chip-mass spectrometry system.Meanwhile,to confirm the metabolic mechanism of aconitine toxicity on HT22 cells,the levels of lactate dehydrogenase,intracellular Ca2+,reactive oxygen species,glutathione and superoxide dismutase,and ratio of Bax/Bcl-2 protein were detected by molecular biotechnology.Integration of the detected results revealed that neurotoxicity induced by aconitine was associated with the process of excitotoxicity caused by glutamic acid and aspartic acid,which was followed by the accumulation of lactic acid and reduction of glucose.The surge of extracellular glutamic acid could further lead to a series of cascade reactions including intracellular Ca2+overload and oxidative stress,and eventually result in cell apoptosis.In general,we illustrated a new mechanism of aconitine neurotoxicity and presented a novel analysis strategy that real-time online monitoring of cell metabolites can provide a new approach to mechanism analysis.

A chiral metal-organic framework {(HQA)(ZnCl2)(2.5H2O)}n for the enantioseparation of chiral amino acids and drugs / 药物分析学报

Chiral metal-organic frameworks(CMOFs)with enantiomeric subunits have been employed in chiral chemistry.In this study,a CMOF formed from 6-methoxyl-(8S,9R)-cinchonan-9-ol-3-carboxylic acid(HQA)and ZnCl2,{(HQA)(ZnCl2)(2.5H2O)｝n was constructed as a chiral stationary phase(CSP)via an in situ fabrication approach and used for chiral amino acid and drug analyses for the first time.The{(HQA)(ZnCl2)(2.5H2O)}n nanocrystal and the corresponding chiral stationary phase were systematically characterised using a series of analytical techniques including scanning electron microscopy,X-ray diffraction,Fourier transform infrared spectroscopy,circular dichroism,X-ray photoelectron spectros-copy,thermogravimetric analysis,and Brunauer-Emmett-Teller surface area measurements.In open-tubular capillary electrochromatography(CEC),the novel chiral column exhibited strong and broad enantioselectivity toward a variety of chiral analytes,including 19 racemic dansyl amino acids and several model chiral drugs(both acidic and basic).The chiral CEC conditions were optimised,and the enantioseparation mechanisms are discussed.This study not only introduces a new high-efficiency member of the MOF-type CSP family but also demonstrates the potential of improving the enantiose-lectivities of traditional chiral recognition reagents by fully using the inherent characteristics of porous organic frameworks.