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1.
Zhongguo Zhong Yao Za Zhi ; 46(12): 3144-3149, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34467706

RESUMO

The effect of intestinal flora changes on the pharmacokinetics of astragaloside Ⅳ in rats with type 2 diabetes mellitus was explored in this study. The rat model in preliminary experiment was established by high-sugar and high-fat diet combined with the intraperitoneal injection of low-dose streptozotocin(STZ). Rats were divided into model group, astragaloside Ⅳ group, berberine group and combination group(five rats in each group). After two weeks of gavage, the rats' feces was taken for 16 S rRNA sequencing of intestinal flora. Pharmacokinetic experiments were performed on astragaloside Ⅳ in the four groups one day after the preliminary experiment. Plasma samples were precipitated in methanol with ginsenoside Rb_1 as an internal standard, and the plasma concentrations of astragaloside Ⅳ at different time points were determined by UPLC-MS/MS. The chromatographic separation was performed on a Waters Acquity UPLC BEH-C_(18) column(2.1 mm×100 mm, 1.7 µm) via gradient elution. The mobile phase was acetonitrile(A) and 5 mmol·L~(-1) ammonium formate solution with 0.2% formic acid(B). The flow rate was 0.4 mL·min~(-1), the injection volume 5 µL and the column temperature 40 ℃. The mass spectrometry was carried out with electrospray ionization source(ESI) in multiple reaction monitoring and positive ion modes. The specificity, linearity range, accuracy, precision, stability and dilution effect of the method all met the requirements for the determination of astragaloside Ⅳ in plasma. Plasma concentration-time curves were plotted and relevant pharmacokinetic parameters were calculated by DAS 3.2.8. The results showed that the concentration of absorbed astragaloside Ⅳ increased within 0-3.95 h and began to decline since 3.95 h. After 36 h, the metabolism was complete. The area under the plasma concentration-time curve(AUC_(0-t)) and the peak concentration(C_(max)) of astragaloside Ⅳ were increased in the three administration groups compared with the model group, but without significant difference, which suggested that the pharmacokinetic characteristics of saponin components would not necessarily change after the drug-induced alteration of intestinal flora.


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Saponinas , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem , Triterpenos
2.
Zhongguo Zhong Yao Za Zhi ; 46(16): 4034-4039, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34467712

RESUMO

As anti-aging ingredients, ß-nicotinamide mononucleotide(NMN) and nicotinamide adenine dinucleotide(NAD~+) have attracted worldwide attention in recent years. After oral administration, NMN can be converted into NAD~+ in vivo and the latter is the actual ingredient which exerts anti-aging effect. In order to explore the "rejuvenating and anti-aging" effect of Dendrobium officinale, which was firstly recorded in Shennong's Herbal Classic of Materia Medica, this study established the quantitative method of UPLC-MS/MS for simultaneous determination of NMN and NAD~+ in D. officinale and the congeneric species for the first time, and 34 batches of samples were detected. UPLC conditions are as follows: ACQUITY UPLC HSS T3 column(2.1 mm × 100 mm, 1.8 µm), gradient elution with acetonitrile-0.1% formic acid in water at the flow rate of 0.3 mL·min~(-1), and column temperature of 40 ℃. MS conditions were scanned electrospray ionization source and multiple reaction monitoring mode. The method was verified by systematic methodology. The mean recoveries of NMN and NAD~+ were 77.58% and 80.70%, respectively, with RSD of 3.6% and 4.3%, separately. All results showed that the content of NMN was higher in D. officinale than in the other congeneric species. Particularly, the content in fresh D. officinale stems was as high as 0.931 9 µg·g~(-1). NAD~+ was only found in D. officinale and the content was three times higher than that of NMN. This may be the reason that D. officinale topped the "nine famous anti-aging herbs". In addition, processing method influences the content of NMN and NAD~+ in Dendrobium. Specifically, the content of NMN and NAD~+ was in the order of fresh Dendrobium stems > dried Dendrobium stem segments > spiral or spring-like dried Dendrobium stems.


Assuntos
Dendrobium , Mononucleotídeo de Nicotinamida , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , NAD , Espectrometria de Massas em Tandem
3.
Zhongguo Zhong Yao Za Zhi ; 46(16): 4244-4251, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34467739

RESUMO

Coumarins are the main active components in Psoraleae Fructus. To study the multi-component pharmacokinetics of Psoraleae Fructus, this study established a sensitive and rapid ultra-pressure liquid chromatography coupled to tandem mass spectrometry(UPLC-MS/MS) method for simultaneous determination of psoralen, isopsoralen, psoralenoside, and isopsoralenoside in rat plasma. After validation, the method was applied to the investigation of pharmacokinetics of psoralen, isopsoralen, psoralenoside, and isopso-ralenoside in rats after single and multiple administration of Psoraleae Fructus extract. The results revealed that the exposure of psoralen and isopsoralen in rat plasma was high after a single intragastric administration of Psoraleae Fructus extract, with an AUC_(0-∞) of 443 619-582 680 and 167 314-276 903 ng·mL~(-1)·h~(-1), respectively. Compared with these two compounds, the exposure of psoralenoside and isopsoralenoside was lower with marked gender difference. After 7-day administration of Psoraleae Fructus extract to rats, the AUC_(0-∞) of psoralen and isopsoralen was 29 701-81 783 and 39 234-89 914 ng·mL~(-1)·h~(-1), respectively, which was significantly lower than that at the first day(P<0.05), and that of psoralenoside and isopsoralenoside was 7 360-19 342 and 8 823-45 501 ng·mL~(-1)·h~(-1), respectively. There was no significant gender difference in exposure of psoralenoside and isopsoralenoside in male and female rats. However, the exposure of psoralenoside and isopsoralenoside in male rats was reduced(P<0.05), and the t_(1/2) and mean residence time(MRT) were shortened, suggesting that the removal of these two compounds from the body was accelerated.


Assuntos
Medicamentos de Ervas Chinesas , Furocumarinas , Psoralea , Administração Oral , Animais , Benzofuranos , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Ficusina , Furocumarinas/análise , Glicosídeos , Ratos , Espectrometria de Massas em Tandem
4.
Shokuhin Eiseigaku Zasshi ; 62(4): 113-118, 2021.
Artigo em Japonês | MEDLINE | ID: mdl-34470939

RESUMO

A method for determining albendazole metabolite (metabolite I) in livestock products using LC-MS/MS was proposed. Livestock samples were hydrolyzed with 6 mol/L HCl at 110℃ for an hour and defatted with ethyl acetate and n-hexane (1 : 1, v/v) mixture. Metabolite I was extracted with acetonitrile from the sample, and the extracts were salted out under basic conditions, allowing the acetonitrile layer to separate. The acetonitrile solution was cleaned up using a cartridge column packed with divinylbenzene-N-vinylpyrolidone copolymer bearing sulfo groups. The HPLC separation was conducted on an Inertsil ODS-4 column with a gradient formed from water containing 0.05% (v/v) formic acid and acetonitrile containing 0.05% (v/v) formic acid. To detect metabolite I, tandem mass spectrometry with positive ion electrospray ionization was used. Truenesses (n=5) of metabolite I from cattle meat, fat, liver, and milk spiked at the maximum residue limits or the 0.01 mg/kg were in the range from 83.6 to 97.9%, and the relative standard deviations were from 1.6 to 6.1%.


Assuntos
Gado , Espectrometria de Massas em Tandem , Albendazol , Animais , Bovinos , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida
5.
Shokuhin Eiseigaku Zasshi ; 62(4): 119-124, 2021.
Artigo em Japonês | MEDLINE | ID: mdl-34470940

RESUMO

A simultaneous determination method for caffeine, theobromine, and theophylline in chocolate was developed. Three compounds were ultrasonically extracted twice (15 min at 50℃) in an acetonitrile-water (1 : 1, v/v). The extract was purified using Oasis HLB SPE cartridge, and the purified processed by LC-MS. The method exhibited recoveries of 97.4-100.2%, RSDs of repeatability of 1.0-2.8%, and RSDs of within-laboratory reproducibility of 2.0-7.9%. This method was simpler and more selective than existing methods, and was practical for caffeine, theobromine, and theophylline analysis in chocolate.


Assuntos
Chocolate , Teobromina , Cafeína , Cromatografia Líquida , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem , Teofilina
6.
Shokuhin Eiseigaku Zasshi ; 62(4): 133-137, 2021.
Artigo em Japonês | MEDLINE | ID: mdl-34470943

RESUMO

A rapid, easy and versatile, simultaneous analytical method by LC-MS/MS based on extraction of QuEChERS method (EN 15662:2008) was developed for the determination of residual pesticides in Edamame (immature soybeans). In this method, it allowed to prepare a test solution only dilution without purification using solid column. As a result, 202 analytes met the management criteria of the guideline for validity assessment (Ministry of Health, Labour and Welfare of Japan). Thus, the present method could be useful for a rapid simultaneous determination of residual pesticides in green soybean.


Assuntos
Resíduos de Praguicidas , Praguicidas , Cromatografia Líquida , Resíduos de Praguicidas/análise , Soja , Espectrometria de Massas em Tandem
7.
Mater Sci Eng C Mater Biol Appl ; 128: 112317, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474868

RESUMO

Acid-triggered degradable polyprodrug P(DOX-AH) was designed for long-acting drug delivery with minimal leakage and enhanced antitumor efficacy. By facile polymerization of doxorubicin (DOX) and N-(tert-butoxycarbonyl)acryloylhydrazine (Boc-AH), P(DOX-AH) with drug as unique repeating unit was obtained, possessing an ultrahigh drug content. It was stable in the neutral media but could degrade completely into DOX-AH in the acidic media without any other by-product. The cleavage of the hydrazone linkage between the DOX-AH repeating units was revealed by the LC-MS/MS analysis. Furthermore, a slow solubility-controlled drug release performance was achieved in the acidic media because of the low solubility of the released DOX-AH. Even with the slow DOX-AH releasing, the enhanced antitumor efficacy was obtained than free DOX in the in vitro cellular experiments. These features demonstrated the promising potential of the proposed polyprodrug for long-acting drug delivery in future tumor chemotherapy.


Assuntos
Polímeros , Espectrometria de Massas em Tandem , Cromatografia Líquida , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Micelas
8.
Artigo em Chinês | MEDLINE | ID: mdl-34488273

RESUMO

Objective: To establish a LC-MS/MS method for determination of paraquat and diquat in plasma and urine samples. Methods: Plasma is precipitated by acetonitrile then diluent with phosphate buffer (pH=7) , urine is diluent with phosphate buffer (pH=7) , then diluent samples extracted with Oasis WCX solid-phase extraction column. Samples were analyzed using LC-MS/MS in multiple reaction monitoring (MRM) mode. The analytical column was XBridge®BEH-HILIC (100 mm×2.1 mm×2.5 µm) and the mobile phase were 100 mmol ammonium formate add 0.5% formic acid and acetonitrile. Paraquat was quantified by internal standard method and diquat by external standard method. Results: The calibration curves of paraquat and diquat were linear in the concentration range of 10.0~120.0 µg/L, the correlation coefficient (r) were 0.9985~0.9994. The limit of detection of paraquat in plasma and urine were 1.98 µg/L and 1.00 µg/L, respectively, the recovery rate were 100.2%~107.3%, the RSD were 1.6%~3.3%. The limit of detection of diquat in plasma and urine were 1.80 µg/L and 2.77 µg/L, respectively, the recovery rate were 85.3%~93.1%, the RSD were 1.8%~5.5%. Conclusion: This method is sensitive and accurate, and can simultaneously determine paraquat and diquat in plasma and urine.


Assuntos
Diquat , Paraquat , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Paraquat/análise , Extração em Fase Sólida , Espectrometria de Massas em Tandem
9.
Anal Chim Acta ; 1178: 338551, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34482862

RESUMO

Single-cell analysis can allow for an in-depth understanding of diseases, diagnostics, and aid the development of therapeutics. However, single-cell analysis is challenging, as samples are both extremely limited in size and complex. But the concept is gaining promise, much due to novel sample preparation approaches and the ever-improving field of mass spectrometry. The mass spectrometer's output is often linked to the preceding compound separation step, typically being liquid chromatography (LC). In this review, we focus on LC's role in single-cell omics. Particle-packed nano LC columns (typically 50-100 µm inner diameter) have traditionally been the tool of choice for limited samples, and are also used for single cells. Several commercial products and systems are emerging with single cells in mind, featuring particle-packed columns or miniaturized pillar array systems. In addition, columns with inner diameters as narrow as 2 µm are being explored to maximize sensitivity. Hence, LC column down-scaling is a key focus in single-cell analysis. But narrow columns are associated with considerable technical challenges, while single cell analysis may be expected to become a "routine" service, requiring higher degrees of robustness and throughput. These challenges and expectations will increase the need and attention for the development (and even the reinvention) of alternative nano LC column formats. Therefore, monolith columns and even open tubular columns may finally find their "killer-application" in single cell analysis.


Assuntos
Análise de Célula Única , Cromatografia Líquida , Espectrometria de Massas
10.
Anal Chim Acta ; 1177: 338760, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34482897

RESUMO

Beta-lactam antibiotics are of vital importance for the treatment of infections in a broad range of patients. Although most systemically administered antibiotics will be excreted renally, a fraction will reach the gastro-intestinal tract, affecting the intestinal microbiome by eradicating a wide range of bacterial species while facilitating the growth of antimicrobial-resistant species. A better understanding of the kinetics of beta-lactam antibiotics in the gastro-intestinal tract is essential to study their role in the development of antibiotic resistance in bacteria and to help develop future therapies to prevent damage to, or restore, the intestinal microbiome. Analysis of beta-lactam antibiotics in faeces is particularly challenging due to the heterogeneous nature of the matrix, rapid degradation of some beta-lactam antibiotics in faeces and very strong ion suppression when using mass spectrometry. Sample preparation was optimized using a sequential strategy of experimental designs. It resulted in lyophilization, a MOPS buffer system and the addition of the beta-lactamase inhibitor avibactam to minimize degradation of antibiotics allowing sensitive quantification. The developed liquid chromatography method with high-resolution mass spectrometric detection was successfully validated according to bioanalytical EMA guidelines and had a linear range of 1-200 µg g-1 lyophilized faeces for amoxicillin, piperacillin and meropenem; and 0.5-100 µg g-1 lyophilized faeces for tazobactam. Despite the highly complex and heterogeneous composition of faeces, the accuracy (0.1-15%) and precision (1.7-12.1%) were in line with those obtained for quantification methods of beta-lactam antibiotics in plasma, the golden standard matrix for therapeutic drug monitoring. The applicability of the method was illustrated by successful quantification of piperacillin and tazobactam in faeces from an intensive care unit patient receiving piperacillin/tazobactam in a continuous intravenous infusion. Both piperacillin and tazobactam were still present six days after discontinuation of the therapy.


Assuntos
Amoxicilina , Piperacilina , Antibacterianos , Cromatografia Líquida , Fezes , Humanos , Espectrometria de Massas , Meropeném , Projetos de Pesquisa , Tazobactam
11.
Anal Chim Acta ; 1177: 338646, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34482900

RESUMO

It is now well-established that dysregulation of the tricarboxylic acid (TCA) cycle enzymes succinate dehydrogenase, fumarate hydratase, and isocitrate dehydrogenase leads to the abnormal cellular accumulation of succinate, fumarate, and 2-hydroxyglutarate, respectively, which contribute to the formation and malignant progression of numerous types of cancers. Thus, these metabolites, called oncometabolites, could potentially be useful as tumour-specific biomarkers and as therapeutic targets. For this reason, the development of analytical methodologies for the accurate identification and determination of their levels in biological matrices is an important task in the field of cancer research. Currently, hyphenated gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS) techniques are the most powerful analytical tools in what concerns high sensitivity and selectivity to achieve such difficult task. In this review, we first provide a brief description of the biological formation of oncometabolites and their oncogenic properties, and then we present an overview and critical assessment of the GC-MS and LC-MS based analytical approaches that are reported in the literature for the determination of oncometabolites in biological samples, such as biofluids, cells, and tissues. Advantages and drawbacks of these approaches will be comparatively discussed. We believe that the present review represents the first attempt to summarize the applications of these hyphenated techniques in the context of oncometabolite analysis, which may be useful to new and existing researchers in this field.


Assuntos
Neoplasias , Biomarcadores Tumorais , Cromatografia Líquida , Humanos , Espectrometria de Massas
12.
Se Pu ; 39(9): 1030-1037, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34486843

RESUMO

Portable analytical instruments find extensive application in on-site examination because of their significant advantages: these instruments are convenient and easy-to-carry, leading to high time-effectiveness, and involve low reagent consumption. We report a portable micro-liquid chromatograph (p-µLC) that was designed and fabricated in our laboratory. The p-µLC integrates homemade dual large-thrust syringe pumps for delivering the mobile phase, a capillary polymer monolithic column as the stationary phase for the separation of the target analytes, and a specially designed dual-functional optical-fiber microflow-cell for online detection. The dual-thrust syringe pumps can realize isocratic and/or gradient elution as well as reloading of the mobile phase, with flow rates ranging from 0.025 µL/min to 5.6 mL/min and the maximum working pressure of 4.5 MPa. The polymethacrylate based C-18 monolithic column facilitates the separation of small organic molecules and biomacromolecules. A homemade high-power light emission diode (LED) light source and a modified xenon flash lamp are assembled as the light source module. The dual-functional detector consists of an optical fiber microflow-cell with a self-focusing lens and a light-guiding capillary, light source module, and a small-sized grating spectrometer with an output wavelength range of 400-680 nm for the LED light source and 220-700 nm for the xenon flash lamp, enabling online detection of the absorption and fluorescence spectra of the analytes from 220 to 700 nm. A bifurcated optical fiber bundle is prepared and used to connect the light source, microflow-cell, and grating spectrometer so that the incident light leading-in and the fluorescence/scatting light leading-out can be realized simultaneously. The junction end of the bifurcated optical fiber bundles connects to one end of the light path of the microflow-cell, and a straight-through optical fiber connects another end of the microflow-cell. In the UV-Vis absorption mode, the straight-through optical fiber reads out the transmitted light, while in the fluorescence mode, the excitation light beam from the light source irradiates the sample solution in the flow-cell via one branch of the bifurcated optic fiber bundles. The fluorescence leading-out via the other branch of the bifurcated optical fiber bundles in the opposite direction of the excitation light beam is read out by the spectrometer. All the large-thrust syringe pumps and flow-path, capillary monolithic column, and optical fiber mediated flow-cell detection as well as controlling modules are installed in a suitcase with a total weight of less than 8 kg. The p-µLC is powered by DC 12V 3A or 18650 lithium battery pack and controlled by a panel computer with a custom-built windows-based chromatography workstation software for data acquisition. When using the home-made polymethacrylate based C-18 monolithic capillary column (530 µm ID×200 mm in length), the mixed alkylbenzenes can be separated and detected in an isocratic elution mode. The separation efficiency is comparable to that obtained with a commercially available HPLC.


Assuntos
Polímeros , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Indicadores e Reagentes
13.
Nanoscale ; 13(31): 13353-13367, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34477741

RESUMO

Despite the significance of surface absorbed proteins in determining the biological identity of nanoparticles (NPs) entering the human body, little is known about the surface corona and factors that shape their formation on dietary particles used as food additives. In this study, food grade NPs of silica and titania and their food additive counterparts (E551 and E171) were interacted with milk proteins or with skimmed milk and the levels of protein adsorption were quantified. Characteristics of proteins correlating with their level of adsorption to NPs were determined using partial least squares regression analysis. Results from individual protein-particle interactions revealed the significance of factors such as zeta potential, hydrophobicity and hydrodynamic size of particles, and protein characteristics such as the number of beta strands, isoelectric points, the number of amino acid units (Ile, Tyr, Ala, Gly, Pro, Asp, and Arg), and phosphorylation sites on their adsorption to particles. Similar regression analysis was performed to identify the characteristics of twenty abundant and enriched proteins (identified using LC-MS/MS analysis) for their association with the surface corona of milk-interacted particles. Contrary to individual protein-particle interactions, protein characteristics such as helices, turns, protein structures, disulfide bonds, the number of amino acid units (Cys, Met, Leu, and Trp), and Fe binding sites were significant for their association with the surface corona of milk interacted particles. This difference in factors identified from individual proteins and milk interacted particles suggested possible interactions of proteins with surface adsorbed biomolecules as revealed by scanning transmission X-ray microscopy and other biochemical assays.


Assuntos
Nanopartículas , Coroa de Proteína , Adsorção , Sequência de Aminoácidos , Cromatografia Líquida , Humanos , Proteoma , Espectrometria de Massas em Tandem
14.
Anticancer Res ; 41(9): 4271-4276, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34475046

RESUMO

BACKGROUND/AIM: The anticancer mechanism of itraconazole remains unsolved; therefore, we studied itraconazole-induced alterations in specialized pro-resolving mediators (SPMs) in cancer cells. MATERIALS AND METHODS: The human cervical squamous carcinoma cell line CaSki was cultured with or without 1 µM itraconazole. Liquid chromatography/mass spectrometry analysis was conducted to identify SPMs that were influenced by itraconazole. Cell growth experiments were conducted using itraconazole and inhibitors targeting the metabolic pathways of candidate SPMs. RESULTS: Resolvin E3, resolvin E2, prostaglandin J2 (PGJ2), delta-12-PGJ2, and maresin 2 were identified as candidate SPMs. The 12/15-lipoxygenase inhibitor, which is involved in the conversion of 18-hydroxy-eicosapentaenoic acid to resolvin E3, attenuated the inhibitory effect of itraconazole. Inhibition of the PGJ2 metabolic pathway did not interfere with itraconazole treatment. CONCLUSION: The metabolic pathway of SPMs, including resolving E3, could be proposed as an anticancer target of itraconazole.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Ácidos Graxos Insaturados/metabolismo , Itraconazol/farmacologia , Inibidores de Lipoxigenase/farmacologia , Neoplasias do Colo do Útero/metabolismo , Carcinoma de Células Escamosas/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Espectrometria de Massas , Redes e Vias Metabólicas/efeitos dos fármacos , Neoplasias do Colo do Útero/tratamento farmacológico
15.
BMC Pediatr ; 21(1): 382, 2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34479539

RESUMO

BACKGROUND: Modifiable lifestyle factors and body composition can affect the attainment of peak bone mass during childhood. This study performed a cross-sectional analysis of the determinants of bone health among pre-adolescent (N = 243) Malaysian children with habitually low calcium intakes and vitamin D status in Kuala Lumpur (PREBONE-Kids Study). METHODS: Body composition, bone mineral density (BMD), and bone mineral content (BMC) at the lumbar spine (LS) and total body (TB) were assessed using dual-energy X-ray absorptiometry (DXA). Calcium intake was assessed using 1-week diet history, MET (metabolic equivalent of task) score using cPAQ physical activity questionnaire, and serum 25(OH) vitamin D using LC-MS/MS. RESULTS: The mean calcium intake was 349 ± 180 mg/day and mean serum 25(OH)D level was 43.9 ± 14.5 nmol/L. In boys, lean mass (LM) was a significant predictor of LSBMC (ß = 0.539, p < 0.001), LSBMD (ß = 0.607, p < 0.001), TBBMC (ß = 0.675, p < 0.001) and TBBMD (ß = 0.481, p < 0.01). Height was a significant predictor of LSBMC (ß = 0.346, p < 0.001) and TBBMC (ß = 0.282, p < 0.001) while fat mass (FM) (ß = 0.261, p = 0.034) and physical activity measured as MET scores (ß = 0.163, p = 0.026) were significant predictors of TBBMD in boys. Among girls, LM was also a significant predictor of LSBMC (ß = 0.620, p < 0.001), LSBMD (ß = 0.700, p < 0.001), TBBMC (ß = 0.542, p < 0.001) and TBBMD (ß = 0.747, p < 0.001). Calcium intake was a significant predictor of LSBMC (ß = 0.102, p = 0.034), TBBMC (ß = 0.122, p < 0.001) and TBBMD (ß = 0.196, p = 0.002) in girls. CONCLUSIONS: LM was the major determinant of BMC and BMD among pre-adolescent Malaysian children alongside other modifiable lifestyle factors such as physical activity and calcium intake.


Assuntos
Densidade Óssea , Espectrometria de Massas em Tandem , Absorciometria de Fóton , Adolescente , Criança , Cromatografia Líquida , Estudos Transversais , Feminino , Nível de Saúde , Humanos , Masculino
16.
Se Pu ; 39(10): 1045-1054, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34505426

RESUMO

Protein glycosylation is one of the most important post-translational modifications (PTMs). The glycosylation is crucial in a variety of physiological and pathological processes that include protein stability, intracellular and intercellular signal transduction, hormone activation or inactivation, and immune regulation. Protein glycosylation is generated by complex biosynthetic pathways comprising hundreds of glycosyltransferases, glycosidases, transcriptional factors, transporters, and protein backbones. Abnormal protein glycosylation is closely associated with the occurrence and development of diseases. Many disease biomarkers in clinical screening are glycoproteins (alfa fetoprotein for liver cancer, carbohydrate antigen 125 for ovarian cancer, carcinoembryonic antigen for colon cancer, prostate-specific antigen for prostate cancer, etc.), and glycan antigens (carbohydrate antigen 19-9 for gastrointestinal cancer and pancreatic cancer, etc.). Glycoproteomics research and technological developments are important to elucidate the mechanism of protein glycosylation in vivo. Mass spectrometry (MS)-based proteomics provides an excellent approach for the comprehensive analysis of proteins and their modifications. In bottom-up proteomics, glycoproteomic analysis is more difficult than other PTMs because intact glycopeptides have diverse peptide backbones and glycan chains, relatively low abundance and ionization efficiency, and pronounced heterogeneity. In recent years, glycoproteomic methodologies such as intact glycopeptide enrichment methods, MS fragmentation and acquisition approaches, MS data interpretation tools and software, and quantification strategies have been appreciably improved. These methodologies have driven in-depth glycoproteomics research. This review focuses on the recent advances in MS-based glycoproteomics. New enrichment methods and spectral interpretation approaches of intact N- and O-glycopeptides are discussed. Their applications in answering various questions in complex biological systems are also considered. The new enrichment methods for intact glycopeptides are mostly based on existing principles. Some properties of the materials, such as hydrophilicity and electrophilicity, have been optimized to improve the enrichment performance. For example, dual-functional Ti(IV)-IMAC materials have been used for the separation of glycopeptides and phosphopeptides. Considering the clinical applications, some glycoproteomics methods integrate enrichment processing into automated workflows to reduce errors caused by manual operations and to increase the experimental reproducibility and efficiency. For example, an automated glycopeptide enrichment method consisting of a liquid chromatograph equipped with a hydrophilic interaction chromatography column has been shown capable of highly reproducible analyses of site-specific glycopeptides in complex biological samples. These methods are more suitable for the discovery of newly glycosylation-related biomarkers as well as for the physiopathological studies of human diseases. With the optimization of glycopeptide enrichment methods and the innovation of MS technologies in the past decade, MS analysis of intact glycopeptides has begun to yield a wealth of glycopeptide fragment ions and plentiful high-quality MS data. This review introduces several effective fragmentation methods for intact glycopeptides. These include collision-induced dissociation, high-energy collision dissociation, electron capture dissociation, electron-transfer dissociation, and electron-transfer/higher-energy collision dissociation. Automated analysis of MS data of intact N- and O-glycopeptides requires interpretation approaches and corresponding software tools with high sensitivity and reliability. Finally, we highlight the utility of several spectral interpretation approaches and their corresponding popular search software, including ArMone, Byonic, GPQuest, pGlyco, O-search, MSFragger-Glyco, and O-Pair Search. In addition, MS data acquisition modes, such as data-dependent acquisition, data-independent acquisition, multiple reaction monitoring technology, and parallel reaction monitoring technology, have great application prospects in glycoproteomics research. With the improvements in enrichment methods, MS technologies, and spectral interpretation approaches for intact N- and O-glycopeptides, comprehensive and systematic glycoproteomics analysis has tremendously expanded the knowledge of protein glycosylation. These glycoproteomic technologies have a wide range of applications that include exploring the molecular mechanisms of protein glycosylation and discovering the new biomarkers of human diseases.


Assuntos
Glicopeptídeos , Espectrometria de Massas em Tandem , Cromatografia Líquida , Humanos , Masculino , Proteômica , Reprodutibilidade dos Testes
17.
Se Pu ; 39(10): 1065-1076, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34505428

RESUMO

The miniaturization of liquid chromatography equipment is among the most important focus areas in chromatographic technology. It involves the miniaturization of the physical dimensions of the instrument, size of the separation material, and inner diameter of the column. The advantages of a reduced inner diameter of the column have been investigated for several decades, and can be summarized as follows. First, the sample consumption is lower, which is particularly beneficial when a limited amount of sample is available, as is the case with natural products, and in biochemistry and biomedicine. Second, the consumption of the mobile phase is reduced, making the process environmentally friendly and facilitating green chemistry. This allows the addition of more expensive solvent additives, such as chiral additives or isotopic reagents, while maintaining a low analysis cost. Moreover, the degree of band dilution in the column is lower than that with conventional liquid chromatography under the same sample injection conditions. Thus, enhanced mass sensitivity is achieved. Other benefits of a reduced inner diameter of the column include temperature control due to effective heat transfer through the columns and easier coupling to mass detectors, which is particularly advantageous for analyzing complex samples. Typically, the term “nano liquid chromatography” is associated with liquid chromatography, which employs capillary columns of inner diameters less than 100 μm and flow rates in the range of tens to hundreds of nanoliters per minute. Because of the extremely low flow rates and small column volume, the extra-column effect becomes more prominent. Thus, the requirements for every component of liquid chromatographs are augmented toward improving their performance and optimizing the extra-column band broadening of the entire system. The solvent delivery equipment should be able to pump mobile phases accurately and steadily at nanoliter-level flow rates. A gradient mode is required to achieve this, which implies that the lowest flow rate for a single pump unit should reach a few nanoliters per minute. A certain operating pressure is also necessary to employ columns with different inner diameters and particle sizes. A precise and repeatable sample injection procedure is essential for nano liquid chromatography. The injection volume and mode should be suitable for capillary columns, without inducing a significant extra-column effect. A higher-sensitivity detector should be employed, and sample dispersion should be limited. The improved tubing and connection method in nano liquid chromatography should offer stability, reliability, and ease of operation. The extra-column volume should also be restricted to suit nanoliter-level flow rates. Considering that most nano liquid chromatographic instruments have been coupled with a mass detector, this review mainly focused on nanoliter solvent delivery modules, sample injection modules, and tubing and connection modules. By searching and summarizing research articles, technical patents, and brochures of instrument manufacturers, technical routes and research progress on these modules were described in detail. The pump designs can be classified into four types. Pneumatic amplifying pumps have been used in ultra-high-pressure applications. The flow-splitting delivery system, though easy to realize, may lead to a large amount of solvent wastage. Splitless pumps, which are classified based on two main principles, are widely used. Some pumps based on other physical phenomena have been suggested; however, they lacked stability and robustness. Two types of injection modes have been utilized in nano liquid chromatography. The direct nanoliter injection mode typically takes advantage of the groove on the rotor of a switching valve. The trapping injection mode uses trap columns to enable the introduction of large sample volumes. As for the tubing and connection, a few appropriate designs can be acquired from commercial suppliers. The robustness has been improved using some patented technologies. The optimization principles and research progress on optical absorption detection are briefly introduced. Finally, commercial nano liquid chromatographic systems are compared by considering the pumps and injectors.


Assuntos
Reprodutibilidade dos Testes , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Tamanho da Partícula , Solventes
18.
Se Pu ; 39(10): 1118-1127, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34505434

RESUMO

The late endosomal/lysosomal adaptor MAPK and mTOR activator 1 (LAMTOR1) is an important regulator protein in the response to energy stress. Public gene expression data shows that the expression of LAMTOR1 is abnormally high in nonalcoholic steatohepatitis (NASH) and hepatocellular carcinoma (HCC); hence, LAMTOR1 may play an important role in the development of NASH and HCC. Therefore, exploring the LAMTOR1 regulatory mechanism in the progression of NASH and malignant transformation of liver inflammation may be crucial for translational medicine. First, a NASH mouse model was established by feeding a methionine choline-deficient (MCD) diet. Hematoxylin-eosin staining of liver tissues showed successful modeling of inflammatory injury in the mouse liver. Immunoblot analysis confirmed LAMTOR1- and LAMTOR1-mediated protein expression in LAMTOR1 specifically depleted mouse livers. Subsequently, metabolic profiling of liver tissues was performed using an ultra-performance liquid chromatography-time-of-flight mass spectrometry strategy. Based on the retention time, m/z value, and tandem mass spectra, 134 metabolites were identified. Among these, the levels of 45 metabolite were significantly influenced by hepatic LAMTOR1 depletion. According to the metabolomics results, uridine diphosphate-N-acetylglucosamine (UDP-GlcNAc) was significantly upregulated in LAMTOR1-depleted (LAMTOR1LKO) hepatocyte tissues. As the final product of the hexosamine biosynthetic pathway (HBP), alteration in UDP-GlcNAc levels may regulate LAMTOR1 and metabolic regulatory genes downstream of HBP. Moreover, there was an obvious increase in the levels of several methylation-related metabolites. Thus, upregulated S-adenosylmethionine, S-adenosylhomocysteine, and N6,N6,N6-trimethyl-L-lysine indicated that LAMTOR1 may regulate the process of DNA or protein methylation. In addition, downregulation of 9-oxo-octadecadienoate, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) was also observed in LAMTOR1LKO mice liver tissues. Alterations in polyunsaturated fatty acids, such as EPA and DHA, link LAMTOR1 to inflammatory and immune processes, which are known to play important roles in NASH pathogenesis. These metabolic disorders demonstrated that LAMTOR1 significantly contributed to the metabolic mechanism of NASH. Furthermore, gene expression correlations were analyzed to interpret the regulatory role of LAMTOR1 from the perspective of genetic networks. Owing to a paucity of liver whole-transcriptome studies in NASH, correlation analysis was performed based on HCC transcriptome data from public databases. First, a negatively regulated relationship was observed between LAMTOR1 and MAT1A (R=-0.47). MAT1A encodes methionine adenosyltransferase 1A, an essential enzyme that catalyzes the formation of S-adenosylmethionine. Based on the upregulation of UDP-GlcNAc under hepatocyte LAMTOR1 depletion, it was predicted that LAMTOR1 positively influenced MGAT1 (R=0.47), a gene encoding alpha-1,3-mannosyl-glycoprotein 2-beta-N-acetylglucosaminyltransferase. Together with changes in succinyladenosine caused by hepatocyte LAMTOR1 deletion, predicted correlation results showed that LAMTOR1 may also participate in the pathogenesis through the positive regulatory relationship with ADSL (R=0.59). The ADSL gene provides instructions for making an enzyme called adenylosuccinate lyase, which can dephosphorylate the substrate succinyladenosine. In this study, LAMTOR1 was identified to specifically regulate multiple key metabolic pathways based on both NASH mouse models and gene expression correlations. These results illustrate the important role of LAMTOR1 in the progression of NASH and malignant transformation of liver inflammation, which provides a theoretical basis for the diagnosis and treatment of NASH or possible NASH-driven HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Cromatografia Líquida , Modelos Animais de Doenças , Inflamação , Fígado , Espectrometria de Massas , Metionina , Camundongos
19.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 33(4): 387-395, 2021 Aug 24.
Artigo em Chinês | MEDLINE | ID: mdl-34505446

RESUMO

OBJECTIVE: To analyze the changes of small molecular metabolites in the larvae of a deltamethrin-sensitive strain of Anopheles sinensis following exposure to deltamethrin, so as to provide the scientific basis for investigating the metabolic pathway and screening metabolic markers of deltamethrin in An. sinensis. METHODS: The 50% and 75% lethal concentrations (LC50 and LC75) of deltamethrin against the larvae of a deltamethrin-sensitive strain of An. sinensis were calculated in laboratory. The type and content of An. sinensis larvae metabolites were detected using high performance liquid chromatography and mass spectrometry (LC-MS/MS) following exposure to deltamethrin at LC50 and LC75 for 30 min and 24 h, and the changes of metabolites were analyzed. RESULTS: The LC50 and LC75 values of deltamethrin were 4.36 × 10-3 µg/mL and 1.12 × 10-2 µg/mL against thelarvae of a deltamethrin-sensitive strain of An. sinensis. Following exposure of the larvae of a deltamethrin-sensitive strain of An. sinensis to deltamethrin at LC50 and LC75 for 30 min, the differential metabolites mainly included organic oxygen compounds, carboxylic acid and its derivatives, fatty acyl and pyrimidine nucleotides, with reduced glucose levels. Following exposure for 24 h, the differential metabolites mainly included organic oxygen compounds, carboxylic acid and its derivatives, aliphatic acyl and purine nucleotides, with increased glucose level detected. CONCLUSIONS: Carbohydrate, carboxylic acid and its derivatives, fatty acyls, amino acids and their derivatives may play important roles in deltamethrin metabolism in the larvae of a deltamethrin-sensitive strain of An. sinensis.


Assuntos
Anopheles , Inseticidas , Animais , Cromatografia Líquida , Larva , Nitrilas , Piretrinas , Espectrometria de Massas em Tandem
20.
Int J Chron Obstruct Pulmon Dis ; 16: 2203-2215, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34349506

RESUMO

Background: Chronic mucous hypersecretion (CMH or chronic bronchitis) per se or when associated with chronic inflammatory airway diseases such as asthma or chronic obstructive pulmonary disease (COPD) has several adverse clinical consequences. The sputum fluid phase has several candidate proteins including mucins which have the potential of being therapeutic targets, but has not yet been explored in-depth. This study aimed at exploring the profile of sputum proteins in various airway diseases. Methods: Sputum from thirty-one patients with various airway diseases was collected and the fluid phase analyzed by LC-MS/MS and subsequently by sequential window acquisition of all theoretical fragments ion spectra (SWATH) (n = 15) for protein quantitation. Hierarchical clustering and functional grouping were performed. Results: A total of 185 proteins were quantitated by SWATH of which 21 proteins were identified which could distinguish between the clinical phenotypes by hierarchical clustering. Functional protein clustering revealed 4 groups: those that are inflammation related, oxidative stress related, mucin related and a cytoskeletal and calcium related group. The levels of eight proteins (Azurocidin1, Neutrophil defensin 3, Lactotransferrin, Calmodulin 3, Coronin1A, Mucin 5B, Mucin 5AC and BPI fold containing family B1) were significantly altered (relative to mean) in exacerbator prone subjects compared to nonexacerbators. Another simple but useful metric which emerged from this study was total protein concentration in sputum which was significantly higher in frequent exacerbators. Conclusion: Sputum proteins can detect the various airway disease clinical phenotypes. Total protein concentration and eight other proteins are biomarkers for frequent exacerbators. The clinical and therapeutic implications of the functional groups of proteins need further evaluation.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Escarro , Biomarcadores , Cromatografia Líquida , Humanos , Projetos Piloto , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Espectrometria de Massas em Tandem
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