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1.
Nat Prod Bioprospect ; 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32613339

RESUMO

Mangiferin is a compound with many pharmacological activities and exists in many natural products. Anhydrous and hydrate of mangiferin have been reported separately in two literatures, but the polymorphism of this compound has not been realized until this paper. In this study, polymorph screening of mangiferin has been carried out and five forms have been obtained including three new forms never reported. Several solid state characterization methods, such as powder X-ray diffraction, differential scanning calorimetry and thermogravimetry, are used to identify and characterize all of mangiferin forms. The comparison of the crystallographic data and hirshfeld surface analysis were first reported for mangiferin anhydrous and hydrate. Furthermore, the studies on stability, transformation and solubility have been undertaken, the results prompt that form V can be used as the dominant polymorph for the development of innovative pharmaceuticals.

2.
BMC Plant Biol ; 20(1): 189, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32357837

RESUMO

BACKGROUND: Colletotrichum species are the causal agents of anthracnose, a major disease affecting the yield and quality of pepper (Capsicum spp.). Colletotrichum scovillei is widespread in China, has strong pathogenicity and drug resistance, and causes anthracnose disease in pepper fruits that severely reduces production. Previously, an anti-anthracnose locus AnRGO5 was mapped to the P5 chromosome on the basis of analyses of fruit at the green mature stage. The aim of this study was to narrow down the interval of this locus and identify the gene responsible for conferring resistance. RESULTS: On the basis of results of re-sequencing of Capsicum chinense 'PBC932' and C. annuum '77013', we developed Kompetitive allele-specific PCR (KASPar) markers and insertion-deletion (InDel) markers linked to AnRGO5 at the green mature fruit stage and used them to construct a genetic linkage map (42 markers, 24.4 cM in length). Using data obtained in phenotypic and genotypic analyses of BC4S1, BC4S2, and BC4S3 populations, AnRGO5 was located between the markers P5in-2266-404 and P5in-2268-978 within a physical distance of 164 kb. This region contained five genes, including CA05g17730. CA05g17730 encodes 'R1C-3-like' putative late blight resistance protein homologs. The transcript level of CA05g17730 differed between 'PBC932' and '77013'. The structure of the CA05g17730 gene also differed between 'PBC932' and '77013'. CONCLUSIONS: We narrowed down the QTL interval to a region containing five genes. These results will be useful for further research on the mechanisms of resistance to anthracnose, and for marker assisted selection for anthracnose-resistant capsicum lines.

3.
Nat Prod Bioprospect ; 2020 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-32306209

RESUMO

Salvianolic acid A (Sal A), a water-soluble ingredient in Danshen, has various biological activities. Sal A and its impurities have similar physical and chemical properties, as well as strong reducibility; therefore, they are difficult to prepare and purify. In this study, high-purity Sal A was obtained by purification of sephadex chromatography and preparative chromatography. Furthermore, HPLC-DAD tandem ECD and HPLC-DAD tandem MS methods were used for non-volatile organic impurity analysis, ICP-MS method was used for non-volatile inorganic impurities and mass balance method and quantitative nuclear magnetic resonance were employed to certify the product. The structures of Sal A and its relative impurities were validated by nuclear magnetic resonance spectroscopy and mass spectrometry, and their contents were quantified as well. Following the principles of ISO Guides 34:2009 and 35:2005, a Sal A reference material was certified, covering homogeneity studies, stability studies, characterization, and uncertainty estimations.

4.
Theor Appl Genet ; 133(4): 1177-1187, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31925462

RESUMO

KEY MESSAGE: A novel strong candidate gene CA00g82510 for the male fertility restoration locus CaRf032 in Capsicum annuum was identified by genome re-sequencing and recombination analysis. A single dominant locus (CaRf032) for fertility restoration of cytoplasmic male sterility was identified in the strong restorer inbred line IVF2014032 of chili pepper (Capsicum annuum L.). CaRf032 was localized within an 8.81-Mb candidate intervals on chromosome 6 using bulked segregant analysis based on high-throughput sequencing data. Subsequently, the candidate interval was genetically mapped and defined to a 249.41-kb region using an F2 population of 441 individuals generated by crossing the male-sterile line 77013A and the restorer line IVF2014032. To fine map CaRf032, eight newly developed KASP markers were used to genotype 23 recombinants screened from a larger F2 population of 2877 individuals. The CaRf032 locus was localized to a 148.05-kb region between the KASP markers S1402 and S1354, which was predicted to contain 22 open reading frames (ORFs). One ORF with an incomplete sequence was predicted to contain a PPR motif, and its physical position overlapped with the Rf candidate gene CaPPR6_46. The PPR ORF sequence before the gap showed 100% identity with the CA00g82510 locus of the CM334 reference genome. CA00g82510 encodes a protein of 583 amino acids, containing 14 PPR motifs, and shows significantly differential expression between the flower buds of the maintainer line 77013 and the restorer line IVF2014032. These results indicated that CA00g82510 is a strong candidate gene for CaRf032. Five KASP markers, which detected single-nucleotide polymorphisms in CA00g82510 of 77013 and IVF2014032, co-segregated with CaRf032 and showed 64.4% successful genotyping of 38 maintainer and 63 restorer lines.

5.
J Colloid Interface Sci ; 543: 84-95, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30782520

RESUMO

Photochlorination method was used to engineer the structural defects and covalent CCl bonds in graphene. Cl coverage of 18 atom% was successfully confirmed by X-ray photoelectron spectroscopy, and D, G and 2D peaks changes upon irradiation were monitored by Raman. The mobility of chlorinated graphene field-effect transistor decreased to 66.1 cm2/(V s) in comparison to pristine graphene of 730.4 cm2/(V s). Raman indicated that the defects and CCl bonds are sensitively associated with the irradiation time, thus the structural defects and composition can be engineered accordingly. Given the creation of active sites, namely the polarization of carbon, as well as fast ionic and electronic transport, chlorinated graphene has demanded features for electrocatalytic reactions. As a proof of concept, chlorinated vertically-oriented graphene grown on carbon cloth (CC@VG) served as excellent bifunctional oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) free-standing electrodes, showing overpotential of 405 mV for OER, Tafel slope of 56 mV, which has better durability than that of commercial Ir/C. Meanwhile, the ORR reduction peak appeared at 0.776 V vs. RHE, more positive than that of carbon cloth (0.60 V). All-solid-state Zn-air battery (ZABs) using chlorinated CC@VG as bifunctional air-cathode showed stable discharge voltage of 1.28 V at current density of 2 mA/cm2, power density of 45.8 mW/cm2 at 80 mA/cm2. More than 108 discharge/charge cycles (20 min per cycle) was obtained at current density of 2 mA/cm2, and round-trip efficiency decreased from 57.4% to 50.0%. Present work developed a universal chlorination method to endow carbonaceous materials with abundant defects and polarized carbon as active site as efficient bifunctional electrocatalysts, and opened a new avenue for developing promising air-cathodes for rechargeable solid-state ZABs.

6.
Steroids ; 143: 18-24, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30513323

RESUMO

Solvatomorphism occurred in diosgenin solvates. A series of solvates including DMSO, DMF, DMAC, Methanol of diosgenin were obtained and crystallized in order to compare their structures and properties in the solid state. Single-crystal X-ray diffraction was used to analyze the crystal structures and the solvent types and the stoichiometric ratio of the diosgenin solvates. Hirshfeld surface analyses, especially dnorm surface and fingerprint plots, were used to determine intermolecular interactions in the crystal structure. Powder X-ray diffraction, differential scanning calorimetry, thermogravimetric, Fourier transform Infrared spectroscopy were all used to characterize the diosgenin solvates. And the solvates transformation have been reported for the first time.


Assuntos
Diosgenina/química , Solventes/química , Modelos Moleculares , Conformação Molecular , Temperatura
7.
J Pharm Biomed Anal ; 140: 169-173, 2017 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-28359964

RESUMO

This paper reports the preparation and characterization of a new chlorogenic acid (CHA) certified reference material (CRM), which is unavailable commercially. CHA is an active ingredient found in many geo-authentic Chinese medicinal materials and developed as an anti-cancer drug. In this work, trace impurities were isolated and identified through various techniques. CHA CRM was quantified with two analytical methods, and their results were in good agreement with each other. The certified value and corresponding expanded uncertainty of CHA CRM reached 99.4%±0.2%, which was calculated by multiplying the combined standard uncertainty by the coverage factor (k=2), at a confidence level of 95%. This CRM can be used to calibrate measurement system, evaluate or validate measurement procedures, assign traceable property values to non-CRMs, and conduct quality control assays.


Assuntos
Alimentos , Ácido Clorogênico , Humanos , Preparações Farmacêuticas , Controle de Qualidade , Padrões de Referência , Incerteza
8.
Cell Physiol Biochem ; 39(5): 1827-1836, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27744427

RESUMO

BACKGROUND/AIMS: Acute and chronic leukemia are severe malignant cancers worldwide, and can occur in pediatric patients. Since bone marrow cell transplantation is seriously limited by the availability of the immune-paired donor sources, the therapy for pediatric leukemia (PL) remains challenging. Autophagy is essential for the regulation of cell survival in the harsh environment. However, the role of autophagy in the survival of PL cells under the oxidative stress, e.g. chemotherapy, remain ill-defined. In the current study, we addressed these questions. METHODS: We analyzed the effects of oxidative stress on the cell viability of PL cells in vitro, using a CCK-8 assay. We analyzed the effects of oxidative stress on the apoptosis and autophagy of PL cells. We analyzed the levels of Beclin-1 and microRNA-93 (miR-93) in PL cells. Prediction of binding between miR-93 and 3'-UTR of Beclin-1 mRNA was performed by a bioinformatics algorithm and confirmed by a dual luciferase reporter assay. The relationship between levels of miR-93 and patients' survival was analyzed in PL patients. RESULTS: We found that oxidative stress dose-dependently increased autophagy in PL cells. While low-level oxidative stress did not increase apoptosis, high-level oxidative stress increased apoptosis, seemingly from failure of autophagy-mediated cell survival. High-level oxidative stress appeared to suppress the protein levels of an autophagy protein Beclin-1 in PL cells, possibly through induction of miR-93, which inhibited the translation of Beclin-1 mRNA via 3'-UTR binding. CONCLUSION: Beclin-1-mediated autophagy plays a key role in the survival of PL cells against oxidative stress. Induction of miR-93 may increase the sensitivity of PL cells to oxidative stress during chemotherapy to improve therapeutic outcome.


Assuntos
Autofagia/efeitos dos fármacos , Proteína Beclina-1/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Regiões 3' não Traduzidas , Antineoplásicos/uso terapêutico , Autofagia/genética , Sequência de Bases , Proteína Beclina-1/metabolismo , Sítios de Ligação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Criança , Pré-Escolar , Feminino , Genes Reporter , Humanos , Peróxido de Hidrogênio/farmacologia , Luciferases/genética , Luciferases/metabolismo , Masculino , MicroRNAs/metabolismo , Estresse Oxidativo , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Biossíntese de Proteínas , Transdução de Sinais , Análise de Sobrevida
9.
Mol Cell Biochem ; 420(1-2): 121-8, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27435859

RESUMO

The purpose of the study was to assess the effect of the internal tandem duplication in FMS-like tyrosine kinase 3 (FLT3-ITD) on the outcome in pediatric acute myeloid leukemia (AML) patients. We identified eligible studies from several databases including PubMed, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) (from January 1995 to July 2015). Ten studies of 1661 pediatric patients with AML were included in exploring the relationship between the FLT3-ITD and overall survival (OS)/event free survival (EFS). Pediatric patients with AML with FLT3-ITD had worse OS [HR = 2.19 (1.60-3.01)]/EFS [HR = 1.70 (1.37-2.11)] than those patients without FLT3-ITD. Furthermore, FLT3-ITD had unfavorable effect on OS/EFS in the subgroups of NOS, uni/multivariate model, number of patients, the length of following-up, and patient source. The findings of this meta-analysis indicated that FLT3-ITD had negative impact on pediatric patients with AML.


Assuntos
Leucemia Mieloide Aguda , Modelos Biológicos , Tirosina Quinase 3 Semelhante a fms , Adolescente , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Humanos , Lactente , Leucemia Mieloide Aguda/enzimologia , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidade , Masculino , Taxa de Sobrevida , Tirosina Quinase 3 Semelhante a fms/genética , Tirosina Quinase 3 Semelhante a fms/metabolismo
10.
ACS Appl Mater Interfaces ; 8(18): 11675-81, 2016 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-27031536

RESUMO

The central problem of using ceramic as a structural material is its brittleness, which associated with rigid covalent or ionic bonds. Whiskers or fibers of strong ceramics such as silicon carbide (SiC) or silicon nitride (Si3N4) are widely embedded in a ceramic matrix to improve the strength and toughness. The incorporation of these insulating fillers can impede the thermal flow in ceramic matrix, thus decrease its thermal shock resistance that is required in some practical applications. Here we demonstrate that the toughness and thermal shock resistance of zirconium diboride (ZrB2)/SiC composites can be improved simultaneously by introducing graphene into composites via electrostatic assembly and subsequent sintering treatment. The incorporated graphene creates weak interfaces of grain boundaries (GBs) and optimal thermal conductance paths inside composites. In comparison to pristine ZrB2-SiC composites, the toughness of (2.0%) ZrB2-SiC/graphene composites exhibited a 61% increasing (from 4.3 to 6.93 MPa·m(1/2)) after spark plasma sintering (SPS); the retained strength after thermal shock increased as high as 74.8% at 400 °C and 304.4% at 500 °C. Present work presents an important guideline for producing high-toughness ceramic-based composites with enhanced thermal shock properties.

12.
J Sci Food Agric ; 95(9): 1885-91, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25170574

RESUMO

BACKGROUND: Neohesperidin is an important natural flavanone glycoside distributed in several citrus species. This compound is widely used as a raw material for food additives in the food industry. The request for certified reference materials (CRMs) in dietary supplements was stipulated by the National Administrative Committee for CRMs and was underpinned by the need to improve the accuracy and comparability of measurement data and to establish metrological traceability of analytical results. RESULTS: This paper reports the sample preparation methodology, homogeneity and stability studies, value assignment and uncertainty estimation of a new certified reference material of neohesperidin (GBW09522). Differential scanning calorimetry, coulometric titration and mass balance methods proved to be sufficiently reliable and accurate for certification purposes. The certified value of neohesperidin CRM is 994 g kg(-1) with an expanded uncertainty of 4 g kg(-1) (k = 2). The reference material described above was homogeneous and stable for 12 months at a storage temperature of 25 °C. CONCLUSION: The new CRM of neohesperidin can be used to validate analytical methods and improve the accuracy of measurement data as well as quality control of neohesperidin-related dietary supplements, foods, traditional herbs and pharmaceutical formulations.


Assuntos
Antioxidantes/análise , Suplementos Nutricionais/análise , Inspeção de Alimentos , Hesperidina/análogos & derivados , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/normas , Calibragem , Varredura Diferencial de Calorimetria , China , Cromatografia Líquida de Alta Pressão , Hesperidina/análise , Hesperidina/química , Hesperidina/isolamento & purificação , Hesperidina/normas , Peso Molecular , Controle de Qualidade , Padrões de Referência , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta , Fatores de Tempo , Titulometria , Incerteza
13.
Steroids ; 92: 25-31, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25174784

RESUMO

Certified reference materials (CRMs) can be used as a valuable tool to validate the trueness of measurement methods and to establish metrological traceability of analytical results. Diosgenin has been selected as a candidate reference material. Characterization of the material relied on two different methods, mass balance method and Coulometric titration method (CT). The certified value of diosgenin CRM is 99.80% with an expanded uncertainty of 0.37% (k=2). The new CRM of diosgenin can be used to validate analytical methods, improve the accuracy of measurement data and control the quality of diosgenin in relevant pharmaceutical formulations.


Assuntos
Diosgenina/análise , Cromatografia Líquida de Alta Pressão , Padrões de Referência
14.
J Pharm Biomed Anal ; 89: 106-10, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24280738

RESUMO

A new certified reference material (CRM) of baicalein was developed aiming to control the quality of baicalein and relative pharmaceuticals. Sample preparation, homogeneity, stability, value assignment, and uncertainty of a new certified reference material (CRM) of baicalein were presented in this paper. Characterization of the material relied on three different methods, which were differential scanning calorimetry (DSC), coulometric titration method (CT) and mass balance method. DSC and CT were used for purity determination of baicalein firstly. The certified value of baicalein CRM is 99.72% with an expanded uncertainty of 0.25% (k=2). The new CRM of baicalein can be used to validate analytical methods, improve the accuracy of measurement data as well as establish meteorological traceability of analytical results.


Assuntos
Flavanonas/química , Varredura Diferencial de Calorimetria/métodos , Peso Molecular , Padrões de Referência , Incerteza
15.
Ying Yong Sheng Tai Xue Bao ; 17(10): 1877-82, 2006 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-17209386

RESUMO

This paper studied the effects of weak light on the photosynthetic characteristics, assimilates allocation, yield formation, and seedling growth of different ecotype capsicum (hot pepper and sweet pepper). The results showed that under weak light, the net photosynthetic rate (Pn) , dark respiration rate (Rd ) , night respiration rate (Rn) , transpiration rate (Tr) , water use efficiency (WUE) , light compensation point (LCP) , CO2 compensation point (CCP) and carboxylation efficiency ( CE) of test capsicums decreased, while their apparent quantum yield (AQY) increased. The decrease of Pn was considered as a result of non-stomata restriction. Weak light increased plant height/stem diameter ratio and specific leaf area, but decreased root/shoot ratio, total dry mass, and seedling' s healthy index. Under the effect of weak light, the formation of biological and economic yields was inhibited significantly, and the allocation of assimilates to stem and leaf was increased while that to fruit decreased. Hot pepper under weak light had lower light compensation point, higher relative healthy index, higher relative yield per plant, and higher relative setting rate, showing a stronger capability of weak light tolerance than sweet pepper.


Assuntos
Capsicum/crescimento & desenvolvimento , Fotossíntese , Luz Solar , Adaptação Fisiológica/genética , Capsicum/genética , Fenótipo
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