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1.
Journal of Forensic Medicine ; (6): 473-477, 2022.
Article in English | WPRIM | ID: wpr-984138

ABSTRACT

OBJECTIVES@#To establish a method to identify unknown sample based on the combined use of Fourier transform infrared spectroscopy (FTIR), gas chromatography-quadrupole time-of-flight mass spectrometry (GC-QTOF-MS), ultra-high performance liquid chromatography-linear ion trap quadrupole-orbitrap mass spectrometry (UPLC-LTQ-Orbitrap MS) and 1H-nuclear magnetic resonance spectroscopy (1H-NMR) technique.@*METHODS@#The unknown sample was directly analyzed by FTIR. The unknown sample was dissolved in methanol solution containing internal standard SKF525A and the supernatant was detected by GC-QTOF-MS and UPLC-LTQ-Orbitrap MS. The unknown sample was dissolved in methanol-d4 solution for structural analysis of 1H-NMR.@*RESULTS@#The characteristic absorption peaks of FTIR spectra obtained from unknown sample were 1 682 (C=O bond), 1 503, 1 488, 1 436, 1 363, 1 256, 1 092, 1 035, 935, 840 and 800 cm-1, the characteristic fragment ions (m/z) of GC-QTOF-MS were 86.096 4 (base peak), 58.065 1, 149.023 5, 121.028 6 and 65.038 6, the accurate mass [M+H]+ detected by UPLC-LTQ-Orbitrap MS was 236.127 7. The sample was identified as synthetic cathinone new psychoactive substance Eutylone by 1H-NMR.@*CONCLUSIONS@#The method established in this study can be used for structural confirmation of Eutylone.


Subject(s)
Methanol , Chromatography, High Pressure Liquid/methods , Mass Spectrometry , Gas Chromatography-Mass Spectrometry/methods , Magnetic Resonance Spectroscopy
2.
Acta Pharmaceutica Sinica B ; (6): 97-105, 2018.
Article in English | WPRIM | ID: wpr-771133

ABSTRACT

Biomimetic nanocarriers are emerging as efficient vehicles to facilitate dietary absorption of biomacromolecules. In this study, two vitamins, thiamine and niacin, are employed to decorate liposomes loaded with insulin, thus facilitating oral absorption vitamin ligand-receptor interactions. Both vitamins are conjugated with stearamine, which works to anchor the ligands to the surface of liposomes. Liposomes prepared under optimum conditions have a mean particle size of 125-150 nm and an insulin entrapment efficiency of approximately 30%-36%. Encapsulation into liposomes helps to stabilize insulin due to improved resistance against enzymatic disruption, with 60% and 80% of the insulin left after 4 h when incubated in simulated gastric and intestinal fluids, respectively, whereas non-encapsulated insulin is broken down completely at 0.5 h. Preservation of insulin bioactivity against preparative stresses is validated by intra-peritoneal injection of insulin after release from various liposomes using the surfactant Triton X-100. In a diabetic rat model chemically induced by streptozotocin, both thiamine- and niacin-decorated liposomes showed a comparable and sustained mild hypoglycemic effect. The superiority of decorated liposomes over conventional liposomes highlights the contribution of vitamin ligands. It is concluded that decoration of liposomes with thiamine or niacin facilitates interactions with gastrointestinal vitamin receptors and thereby facilitates oral absorption of insulin-loaded liposomes.

3.
West China Journal of Stomatology ; (6): 360-366, 2018.
Article in Chinese | WPRIM | ID: wpr-688006

ABSTRACT

<p><b>OBJECTIVE</b>This study intends to explore the mechanism underlying the support of sortase A (SrtA) of the cariogenicity of Streptococcus mutans (S. mutans).</p><p><b>METHODS</b>We performed a metabonomics study based on ¹H nuclear magnetic resonance spectroscopy (NMR), in which we compared the extracellular metabolites of wild-type S. mutans UA159 with those of its SrtA-deficient strain. Metabolite differences among strains were identified using a combination of principal component analysis and orthogonality partial least square discriminant analysis.</p><p><b>RESULTS</b>Several differences corresponding mostly to unknown metabolites were identified. Some amino acids such as leucine and valine (δ 0.92×10⁻⁶-1.20×10⁻⁶), lactic acid ( δ1.28×10⁻⁶), oxoglutaric acid (δ 3.00×10⁻⁶), and glycine (δ 3.60×10⁻⁶) differed among strains.</p><p><b>CONCLUSIONS</b>This work establishes the feasibility of using ¹H NMR-based metabonomics to provide leads for research into molecular factors that promote caries. The database of microbial metabolites should be also improved in further studies.</p>

4.
Chinese Pharmacological Bulletin ; (12): 853-857, 2016.
Article in Chinese | WPRIM | ID: wpr-493824

ABSTRACT

Aim Toanalyzethecharacteristicsofser-um metabolites in immune suppression mice by using 1HNMR-basedmetabonomics.Methods Twentymale Kunming(KM)mice were randomly divided into two groups:normal group and cyclophosphamide (Cy ) model group.Cy model group was given Cy to induce immune suppression.NMR technology was used to find out the variability of serum metabolites by the method ofOPLS-DA.Results Comparedwithnormalgroup, Cy model group showed a significant decrease in the serum levels of glutamine,glycolprotein,unsaturated lipid,VLDL,LDL,acetone and showed a significant increase in the serum levels of leucine,alanine,tyro-sine, histidine, lactate, glycine, creatine, me-theionine,valine,β-hydrocxy butyrate and carnitine. Conclusions Immunesuppressionmiceareimbal-anced in metabolic network.These findings indicate that lipid metabolism-related metabolites are de-creased,however,β-oxidation of fatty acid,proteoly-sis and glycolysis level are increased.

5.
China Occupational Medicine ; (6): 525-530, 2016.
Article in Chinese | WPRIM | ID: wpr-876981

ABSTRACT

OBJECTIVE: To screen small molecule metabolites of dibutyl phthalate( DBP) in the rat plasma using ~1H nuclear magnetic resonance( NMR) technology; and to clarify the changes of metabolites and possible mechanism in metabolic regulation of DBP in rats from the molecular level and the aspects of material and energy metabolism. METHODS: According to random number table method,twenty-four specific pathogen free SD male rats were divided into four groups: control group,low dose group,middle dose group and high dose group with the given dose of 0,500,1 000 and1 500 mg / kg of body mass,respectively. After giving DBP of gavage once a day for two weeks,the plasma samples were obtained,and ~1H NMR spectra was recorded. The plasma metabonomic profiles were analyzed using pattern recognition.Difference metabolites were screened by principal components analysis,partial least squares-discriminate analysis and orthogonal partial least squares-discriminate analysis. Biomarkers was screened by variable importance in the projection norm. RESULTS: There were changes of twelve important metabolites in the plasma metabonomic profiles between DBP treatment groups and control group. The differences of metabolites had dose-effect relationship. Plasma levels of high density lipoprotein cholesterol, low density lipoprotein cholesterol, hydrobutyrate, glycoprotein, citric acid, glucose,creatine phosphate,unsaturated fatty acid,tyrosine and phenylalanine were reduced( P < 0. 05),while lactic acid and pyruvic acid were increased( P < 0. 05). CONCLUSION: DBP induces the metabolic disorders including amino acid metabolism,lipid metabolism and energy metabolism.

6.
Chinese Journal of Endocrinology and Metabolism ; (12): 11-15, 2012.
Article in Chinese | WPRIM | ID: wpr-417782

ABSTRACT

ObjectiveTo study the characteristics of serum metabolites in two Uyghur families with maturityonset diabetes of the young(MODY).MethodsTwo MODY families were composed of four generations of Uyghur with 52 members collected from Kashgar region,Xinjiang Uyghur Autonomous Region.The general information,blood glucose and lipid levels,and blood pressure were analyzed.Using 1H nuclear magnetic resonance (1H NMR )spectroscopy,serum metabolites were measured for each subject.After having conducted data pretreatment on the spectrogram,orthogonal partial least squares discriminant analysis ( OPLS-DA ) was used to interpret data.The subjects were divided into two groups according to blood glucose ( diabetes and non-diabetes ),blood pressure,body mass index ( BMI ) for comparing differences in the metabolites.The differences of serum metabolic components between two groups were determined using pearson correlation coefficients with significant difference detection and two-dimensional spectrum technology.Results lsoleucine and tyrosine levels in diabetes group were decreased significantly,while α-glucose and β-glucose levels were increased significantly compared with non-diabetes group( all P<0.05 ).Citrate,phaseomannite,1 -methyl histidine,and tyrosine levels in hypertension group were all decreased significantly compared with normal blood pressure group( all P<0.05 ).No significant metabonomic differences were observed between normal BMI group and high BMI group.ConclusionsMetabonomic changes in diabetic patients from MODY families indicate that diabetic patients suffer from disordered tricarboxylic acid cycle ( TCA cycle )metabolism,with reduced glycolysis of glycogen in liver and muscle.There exist the metabolic disorder in TCA cycle and obstruction of fat metabolism in patients with hypertension from the MODY families.

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