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1.
Front Neurosci ; 16: 953842, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36033621

RESUMO

Background: Non-suicidal self-injury (NSSI) is an important risk factor for suicide in adolescents with depressive disorders; therefore, it is important to predict NSSI occurrence as early as possible. Disturbances in biological rhythms are characteristic manifestations of depressive disorders and can lead to immune dysfunction, leading to changes in tumor markers. This study aimed to produce an index that utilizes tumor markers to predict NSSI behaviors among adolescents with depressive disorders. Methods: A total of 120 hospitalized adolescent patients with depressive disorders aged 14-24 years were included in this study. Participants were divided into NSSI and non-NSSI groups based on self-reports using the Ottawa Self-Injury Inventory. Demographics, tumor marker concentrations, other peripheral blood indices, Hamilton Depression Rating Scale (HDRS) scores, and Hamilton Anxiety Rating Scale (HAMA) scores were compared between the two groups. Logistic regression analysis was conducted to develop a joint index, and a receiver operating characteristic (ROC) curve was created to predict NSSI behaviors among adolescents with depressive disorders. Results: Compared with the non-NSSI group, the NSSI group had significantly higher insight, retardation, insomnia, hopelessness, psychiatric anxiety, total HDRS and HAMA scores, and significantly higher levels of cancer antigen 125 (CA-125), cancer antigen 19-9 (CA19-9), and carcinoembryonic antigen (CEA). In addition, a joint index was developed by combining CA-125, CA19-9, CEA, HDRS total score, HAMA total score and age using multiple logistic regression to predict NSSI behaviors. The area under the curve was 0.831, with a sensitivity and specificity of 0.734 and 0.891, respectively. Conclusion: A combination of depression score, tumor marker levels, and age can identify NSSI behaviors among adolescents with depressive disorders.

2.
J Chromatogr A ; 1393: 47-56, 2015 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-25818557

RESUMO

Solvent system selection is the first step toward a successful counter-current chromatography (CCC) separation. This paper introduces a systematic and practical solvent system selection strategy based on the nonrandom two-liquid segment activity coefficient (NRTL-SAC) model, which is efficient in predicting the solute partition coefficient. Firstly, the application of the NRTL-SAC method was extended to the ethyl acetate/n-butanol/water and chloroform/methanol/water solvent system families. Moreover, the versatility and predictive capability of the NRTL-SAC method were investigated. The results indicate that the solute molecular parameters identified from hexane/ethyl acetate/methanol/water solvent system family are capable of predicting a large number of partition coefficients in several other different solvent system families. The NRTL-SAC strategy was further validated by successfully separating five components from Salvia plebeian R.Br. We therefore propose that NRTL-SAC is a promising high throughput method for rapid solvent system selection and highly adaptable to screen suitable solvent system for real-life CCC separation.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Distribuição Contracorrente/métodos , Solventes/química , 1-Butanol/química , Acetatos/química , Clorofórmio/química , Hexanos/química , Metanol/química , Extratos Vegetais/química , Salvia/química , Água/química
3.
J Chromatogr A ; 1355: 80-5, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24951288

RESUMO

Selection of an appropriate solvent system is of great importance for a successful counter-current chromatography separation. In this work, the nonrandom two-liquid (NRTL) model, a thermodynamic method, was used for predicting the partition coefficient based on a few measured partition coefficients. The NRTL method provides quite satisfactory results for model solutes in first correlating measured partition coefficient in a few representative biphasic liquid systems and then successfully predicting partition coefficient in other two-phase liquid systems. According to the predicted partition coefficient, a suitable solvent system can be screened. Assisted with the NRTL method, the solvent system composed of hexane/ethyl acetate/methanol/water (1:4:1:4, v/v) was rapidly screened for the successful separation of two major compounds with high purity from Malus hupehensis leaves. The results demonstrated that the NRTL model can offer a simple and practical strategy to estimate partition coefficients in support of CCC solvent system selection, which will significantly minimize the experimental efforts and cost involved in solvent system selection.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Distribuição Contracorrente/métodos , Acetatos/química , Cromatografia Líquida de Alta Pressão/instrumentação , Distribuição Contracorrente/instrumentação , Hexanos/química , Metanol/química , Solventes/química , Termodinâmica , Água/química
4.
J Sep Sci ; 37(16): 2118-25, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24854200

RESUMO

Nine compounds were successfully separated from Salvia plebeia R.Br. using two-step high-speed counter-current chromatography with three elution modes. Elution-extrusion counter-current chromatography was applied in the first step, while classical counter-current chromatography and recycling counter-current chromatography were used in the second step. Three solvent systems, n-hexane/ethyl acetate/ethanol/water (4:6.5:3:7, v/v), methyl tert-butyl ether/ethyl acetate/n-butanol/methanol/water (6:4:1:2:8, v/v) and n-hexane/ethyl acetate/methanol/water (5:5.5:5:5, v/v) were screened and optimized for the two-step separation. The separation yielded nine compounds, including caffeic acid (1), 6-hydroxyluteuolin-7-glucoside (2), 5,7,3',4'-tetrahydroxy-6-methoxyflavanone-7-glucoside (3), nepitrin (4), rosmarinic acid (5), homoplantaginin (6), nepetin (7), hispidulin (8), and 5,6,7,4'-tertrahydroxyflavone (9). To the best of our knowledge, 5,7,3',4'-tetrahydroxy-6-methoxyflavanone-7-glucoside and 5,6,7,4'-tertrahydroxyflavone have been separated from Salvia plebeia R.Br. for the first time. The purities and structures of these compounds were identified by high-performance liquid chromatography, electrospray ionization mass spectrometry, (1)H and (13)C NMR spectroscopy. This study demonstrates that high-speed counter-current chromatography is a useful and flexible tool for the separation of components from a complex sample.


Assuntos
Medicamentos de Ervas Chinesas/análise , Extratos Vegetais/análise , Salvia/química , 1-Butanol/química , Acetatos/química , Cromatografia Líquida de Alta Pressão , Distribuição Contracorrente , Etanol/química , Hexanos/química , Metanol/química , Éteres Metílicos/química , Solventes , Água/química
5.
Planta ; 236(6): 1849-61, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22922880

RESUMO

Each plant species in nature harbors endophytes, a community of microbes living within host plants without causing any disease symptom. However, the exploitation of endophyte-based phytoprotectants is hampered by the paucity of mechanistic understandings of endophyte-plant interaction. We here reported two endophytic Streptomyces isolates IFB-A02 and IFB-A03 recovered from a stress-tolerant dicotyledonous plant Artemisia annua L. After the determination of their non-pathogenicity at the genomic level and from the toxin (thaxtomin A, TXT) level, the endophytism of both isolates was supported by their successful colonization in planta. Of the two endophytes, IFB-A03 was further studied for the mechanism of endophyte-conferred phytoprotection owing to its plant growth promotion in model eudicot Arabidopsis thaliana. Using the endophyte-Arabidopsis co-cultivation system into which pathogenic Streptomyces scabies was introduced, we demonstrated that IFB-A03 pre-inoculation could activate the salicylic acid (SA)-mediated plant defense responses upon pathogen challenge. Moreover, IFB-A03 was shown to partially rescue the defense deficiency in eds5 (enhanced disease susceptibility 5) Arabidopsis mutants, putatively acting at the upstream of SA accumulation in the defense signaling pathway associated with the systemic acquired resistance (SAR). These data suggest that endophytic Streptomyces sp. IFB-A03 could be a promising candidate for biocontrol agents against S. scabies--a causative pathogen of common scab diseases prevailing in agronomic systems.


Assuntos
Arabidopsis/microbiologia , Artemisia/microbiologia , Indóis/metabolismo , Piperazinas/metabolismo , Doenças das Plantas/microbiologia , Streptomyces/fisiologia , Arabidopsis/imunologia , Proteínas de Arabidopsis/genética , Artemisia/imunologia , Proteção Cruzada , Endófitos , Proteínas de Membrana Transportadoras/genética , Mutação , Filogenia , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Imunidade Vegetal , Ácido Salicílico/análise , Ácido Salicílico/metabolismo , Plântula/imunologia , Plântula/microbiologia , Transdução de Sinais , Streptomyces/isolamento & purificação , Streptomyces/patogenicidade
6.
Planta Med ; 78(10): 1015-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22628156

RESUMO

Bioassay-guided investigation of the stem bark of Hopea chinensis led to the isolation of two new polyphenols, hopeachinols C(1) and D(2), together with ten known compounds (3-12). Compounds 1 and 2 were determined by extensive analysis of spectroscopic data and computational methods. All of these phytochemicals were tested for acetylcholinesterase inhibitory activity, and five resveratrol-derived compounds (1 and 7-10) exhibited significant activity with their IC50 values ranging from 4.81 to 11.71 µM.


Assuntos
Inibidores da Colinesterase/isolamento & purificação , Dipterocarpaceae/química , Polifenóis/farmacologia , Benzofuranos/química , Benzofuranos/isolamento & purificação , Benzofuranos/farmacologia , Fracionamento Químico/métodos , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Biologia Computacional/métodos , Ensaios Enzimáticos/métodos , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Conformação Molecular , Casca de Planta/química , Caules de Planta/química , Polifenóis/química , Polifenóis/isolamento & purificação , Resveratrol , Estilbenos/química
7.
Chemistry ; 18(17): 5213-21, 2012 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-22434621

RESUMO

Bioactive natural products offer multiple opportunities for the discovery of novel chemical entities with potential pharmaceutical, nutraceutical and agrochemical applications. Many new organic compounds with novel scaffolds are isolated in small quantities and established methods often fail to determine the structure and bioactivity of such novel natural products. To meet this challenge, we present here a new methodology combining RDC (residual dipolar coupling)-based NMR spectroscopy in microtubes, with a motif-inspired biological assessment strategy. Using only one milligram (ca. 1.5 µmol) of sample, the new protocol established the bioactivity as well as the relative and absolute configuration of vatiparol obtained from Vatica parvifolia. Vatiparol is unique in its unprecedented carbon skeleton and selective inhibitory effect on the expression of monocyte chemo-attractant protein-1 (MCP-1, also known as CCL2). The plausible biosynthetic pathway of vatiparol is briefly discussed. The approach introduced here promises to be widely applicable to the determination of the structure and bioactivity of structurally unknown organic samples available in very limited amounts.


Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Compostos Heterocíclicos de 4 ou mais Anéis/química , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Polifenóis/química , Polifenóis/farmacologia , Espectroscopia de Ressonância Magnética/métodos , Modelos Químicos , Estereoisomerismo
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