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1.
Chem Biodivers ; 21(6): e202400159, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38563619

RESUMEN

While the flowers of Matricaria recutita L., German chamomile, are widely used for medicinal and cosmetic purposes, little is known about its roots, which are used in complementary medicine for the preparation of aqueous fermented extracts for the treatment of cramps and anxiety. To broaden the understanding of the active principles involved, a model fermentation approach was developed and fermentates were compared to commercially manufactured tinctures. Coumarins and hydroxycinnamates were among the major secondary metabolites characterized using HPLC-MSn. After six months of fermentation and storage, low-molecular organic acids were detected by GC-MS. Fermentation contributed to the stabilization of antioxidant and radical scavenging activities, which were in a range of about 8-10 mg gallic acid equivalents/g dry weight and 20-24 mg trolox equivalents/g dry weight, determined by Folin-Ciocalteu and DPPH assays, respectively. In addition, antibacterial activities of the extracts against Gram-positive and -negative bacteria increased during the first week of fermentation. Fermentates were neither cytotoxic nor pro- or anti-inflammatory. Thus, fermentation of chamomile roots is a suitable method for the safe production of biofunctional aqueous chamomile root extracts that remain stable without the addition of synthetic preservatives.


Asunto(s)
Antioxidantes , Fermentación , Matricaria , Fitoquímicos , Extractos Vegetales , Raíces de Plantas , Raíces de Plantas/química , Raíces de Plantas/metabolismo , Matricaria/química , Matricaria/metabolismo , Extractos Vegetales/química , Extractos Vegetales/farmacología , Extractos Vegetales/aislamiento & purificación , Antioxidantes/farmacología , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Antioxidantes/metabolismo , Fitoquímicos/química , Fitoquímicos/farmacología , Fitoquímicos/aislamiento & purificación , Fitoquímicos/metabolismo , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Humanos , Agua/química , Animales , Picratos/antagonistas & inhibidores , Compuestos de Bifenilo/antagonistas & inhibidores , Supervivencia Celular/efectos de los fármacos
2.
Cleft Palate Craniofac J ; 60(6): 758-767, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-35167404

RESUMEN

We recently published the 3-month follow-up of 2 neonates with Robin sequence whose mandibular hypoplasia and restricted airway were successfully treated with an orthodontic airway plate (OAP) without surgical intervention. Both infants were successfully weaned off the OAP after several months of continuous use. We present the course of OAP treatment in these patients with a focus on breathing, feeding, and facial growth during their first year of life. Both infants demonstrated stable mandibular projection, resolution of obstructive sleep apnea, and normal development.


Asunto(s)
Obstrucción de las Vías Aéreas , Osteogénesis por Distracción , Síndrome de Pierre Robin , Apnea Obstructiva del Sueño , Lactante , Recién Nacido , Humanos , Estudios de Seguimiento , Síndrome de Pierre Robin/terapia , Resultado del Tratamiento , Mandíbula/cirugía , Obstrucción de las Vías Aéreas/cirugía , Estudios Retrospectivos
3.
Chembiochem ; 23(20): e202200390, 2022 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-35950614

RESUMEN

Accurate formation of antibody-antigen complexes has been relied on in both, multitudes of scientific projects and ample therapeutic and diagnostic applications. Mass spectrometrically determined dissociation behavior of immune complexes with the anti-HpTGEKP antibody revealed that the ten most frequently occurring phospho-hexapeptide linker sequences from C2H2 zinc finger proteins could be divided into two classes: orthodox binders, where strong noncovalent interactions developed as anticipated, and unorthodox binders with deviating structures and weaker binding. Phosphorylation of threonine was compulsory for antibody binding in an orthodox manner. Gas phase dissociation energy determinations of seven C2H2 zinc finger protein linker phospho-hexapeptides with orthodox binding properties revealed a bipolar binding motif of the antibody paratope. Epitope peptides, which in addition to the negatively charged phospho-threonine residue were C-terminally flanked by positively charged residues provided stronger binding, i. e. dissociation was endothermic, than peptides with acidic amino acid residues at these positions, for which dissociation was exothermic.


Asunto(s)
Anticuerpos Monoclonales , Complejo Antígeno-Anticuerpo , Dedos de Zinc , Espectrometría de Masas , Epítopos/química , Péptidos/química , Treonina , Aminoácidos Acídicos
4.
J Gen Intern Med ; 37(6): 1351-1358, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35266122

RESUMEN

OBJECTIVES: To examine city-level kidney disease mortality rates and Black:White racial inequities for the USA and its largest cities, and to determine if these measures changed over the past decade. METHODS: We used National Vital Statistics System mortality data and American Community Survey population estimates to calculate age-standardized kidney disease mortality rates for the non-Hispanic Black (Black), non-Hispanic White (White), and total populations for the USA and the 30 most populous US cities. We examined two time points, 2008-2013 (T1) and 2014-2018 (T2), and assessed changes in rates and inequities over time. Racial inequities were measured with Black:White mortality rate ratios and rate differences. RESULTS: Kidney disease mortality rates varied from 2.5 (per 100,000) in San Diego to 24.6 in Houston at T2. The Black kidney disease mortality rate was higher than the White rate in the USA and all cities studied at both time points. In T2, the Black mortality rate ranged from 7.9 in New York to 45.4 in Charlotte, while the White mortality rate ranged from 2.0 in San Diego to 18.6 in Indianapolis. At T2, the Black:White rate ratio ranged from 1.79 (95% CI 1.62-1.99) in Philadelphia to 5.25 (95% CI 3.40-8.10) in Washington, DC, compared to the US rate ratio of 2.28 (95% CI 2.25-2.30). Between T1 and T2, only one city (Nashville) saw a significant decrease in the Black:White mortality gap. CONCLUSIONS: The largest US cities experience widely varying kidney disease mortality rates and widespread racial inequities. These local data on racial inequities in kidney disease mortality can be used by city leaders and health stakeholders to increase awareness, guide the allocation of limited resources, monitor trends over time, and support targeted population health strategies.


Asunto(s)
Enfermedades Renales , Población Blanca , Negro o Afroamericano , Ciudades/epidemiología , Femenino , Humanos , Masculino , Grupos Raciales , Estados Unidos/epidemiología
5.
AIDS Care ; 34(7): 916-925, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-34125639

RESUMEN

BACKGROUND: Despite decreases in overall HIV mortality in the U.S., large racial inequities persist. Most previous analyses of HIV mortality and mortality inequities have utilized national- or state-level data. METHODS: Using vital statistics mortality data and American Community Survey population estimates, we calculated HIV mortality rates and Black:White HIV mortality rate ratios (RR) for the 30 most populous U.S. cities at two time points, 2010-2014 (T1) and 2015-2019 (T2). RESULTS: Almost all cities (28) had HIV mortality rates higher than the national rate at both time points. At T2, HIV mortality rates ranged from 0.8 per 100,000 (San Jose, CA) to 15.2 per 100,000 (Baltimore, MD). Across cities, Black people were approximately 2-8 times more likely to die from HIV compared to White people at both time points. Over the decade, these racial disparities decreased at the national level (T1: RR = 11.0, T2: RR = 9.8), and in one city (Charlotte, NC). DISCUSSION: We identified large geographic and racial inequities in HIV mortality in U.S. urban areas. These city-specific data may motivate change in cities and can help guide city leaders and other health advocates as they implement, test, and support policies and programming to decrease HIV mortality.


Asunto(s)
Infecciones por VIH , Población Blanca , Negro o Afroamericano , Ciudades/epidemiología , Humanos , Grupos Raciales , Estados Unidos/epidemiología
6.
PLoS Genet ; 15(2): e1007961, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30730892

RESUMEN

Genome-wide association studies have identified more than 200 genetic variants to be associated with an increased risk of developing multiple sclerosis (MS). Still, little is known about the causal molecular mechanisms that underlie the genetic contribution to disease susceptibility. In this study, we investigated the role of the single-nucleotide polymorphism (SNP) rs1414273, which is located within the microRNA-548ac stem-loop sequence in the first intron of the CD58 gene. We conducted an expression quantitative trait locus (eQTL) analysis based on public RNA-sequencing and microarray data of blood-derived cells of more than 1000 subjects. Additionally, CD58 transcripts and mature hsa-miR-548ac molecules were measured using real-time PCR in peripheral blood samples of 32 MS patients. Cell culture experiments were performed to evaluate the efficiency of Drosha-mediated stem-loop processing dependent on genotype and to determine the target genes of this underexplored microRNA. Across different global populations and data sets, carriers of the MS risk allele showed reduced CD58 mRNA levels but increased hsa-miR-548ac levels. We provide evidence that the SNP rs1414273 might alter Drosha cleavage activity, thereby provoking partial uncoupling of CD58 gene expression and microRNA-548ac production from the shared primary transcript in immune cells. Moreover, the microRNA was found to regulate genes, which participate in inflammatory processes and in controlling the balance of protein folding and degradation. We thus uncovered new regulatory implications of the MS-associated haplotype of the CD58 gene locus, and we remind that paradoxical findings can be encountered in the analysis of eQTLs upon data aggregation. Our study illustrates that a better understanding of RNA processing events might help to establish the functional nature of genetic variants, which predispose to inflammatory and neurological diseases.


Asunto(s)
Antígenos CD58/genética , MicroARNs/genética , Esclerosis Múltiple/genética , Polimorfismo de Nucleótido Simple , Antígenos CD58/metabolismo , Estudios de Cohortes , Simulación por Computador , Femenino , Estudios de Asociación Genética , Estudio de Asociación del Genoma Completo , Células HeLa , Humanos , Intrones , Masculino , MicroARNs/química , MicroARNs/metabolismo , Persona de Mediana Edad , Modelos Genéticos , Esclerosis Múltiple/inmunología , Esclerosis Múltiple/metabolismo , Conformación de Ácido Nucleico , Sitios de Carácter Cuantitativo , Procesamiento Postranscripcional del ARN , ARN Mensajero/genética , ARN Mensajero/metabolismo
7.
Chem Biodivers ; 19(2): e202100850, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34882948

RESUMEN

Preparations derived from roots and rhizomes of Geum urbanum L. are traditionally used for the treatment of ulcers and irritations of mucous membranes of the mouth, stomach, and intestinal tract. In complementary medicine, fermentation is one of the methods applied to recover plant extracts used for the production of such pharmaceutical preparations. The present study was performed to characterize the secondary metabolites and to evaluate the antimicrobial potential of different G. urbanum root and rhizome extracts. For this purpose, individual metabolites of fresh and fermented G. urbanum root and rhizome extracts were analyzed by HPLC-DAD-MSn and GC/MS. Among others, rare ellagitannin-sulfates could be characterized by LC/MSn . In addition, the antibacterial activity of various extracts of fresh and dried G. urbanum roots and rhizomes against Staphylococcus aureus (ATCC 6538) and Cutibacterium acnes (CP033842.1; FDAARGOS 503 chromosome) were assessed and compared to that of G. rivale. Furthermore, low- and high-molecular tannins were fractionated by column chromatography, demonstrating the latter to exhibit highest antibacterial activity.


Asunto(s)
Geum , Antibacterianos/farmacología , Cromatografía Líquida de Alta Presión , Geum/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Taninos/análisis
8.
Int J Mol Sci ; 23(3)2022 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-35162997

RESUMEN

Krüppel-associated box (KRAB) zinc finger proteins are a large class of tetrapod transcription factors that usually exert transcriptional repression through recruitment of TRIM28/KAP1. The evolutionary root of modern KRAB domains (mKRAB) can be traced back to an ancestral motif (aKRAB) that occurs even in invertebrates. Here, we first stratified three subgroups of aKRAB sequences from the animal kingdom (PRDM9, SSX and coelacanth KZNF families) and defined ancestral subdomains for KRAB-A and KRAB-B. Using human ZNF10 mKRAB-AB as blueprints for function, we then identified the necessary amino acid changes that transform the inactive aKRAB-A of human PRDM9 into an mKRAB domain capable of mediating silencing and complexing TRIM28/KAP1 in human cells when employed as a hybrid with ZNF10-B. Full gain of function required replacement of residues KR by the conserved motif MLE (positionsA32-A34), which inserted an additional residue, and exchange of A9/S for F, A20/M for L, and A27/R for V. AlphaFold2 modelling documented an evolutionary conserved L-shaped body of two α-helices in all KRAB domains. It is transformed into a characteristic spatial arrangement typical for mKRAB-AB upon the amino acid replacements and in conjunction with a third helix supplied by mKRAB-B. Side-chains pointing outward from the core KRAB 3D structure may reveal a protein-protein interaction code enabling graded binding of TRIM28 to different KRAB domains. Our data provide basic insights into structure-function relationships and emulate transitions of KRAB during evolution.


Asunto(s)
N-Metiltransferasa de Histona-Lisina/química , N-Metiltransferasa de Histona-Lisina/metabolismo , Invertebrados/metabolismo , Factores de Transcripción de Tipo Kruppel/química , Proteínas Represoras/química , Proteína 28 que Contiene Motivos Tripartito/metabolismo , Secuencia de Aminoácidos , Animales , Sitios de Unión , Secuencia Conservada , Evolución Molecular , Mutación con Ganancia de Función , N-Metiltransferasa de Histona-Lisina/genética , Humanos , Factores de Transcripción de Tipo Kruppel/genética , Modelos Moleculares , Conformación Proteica en Hélice alfa , Dominios Proteicos , Proteínas Represoras/genética
9.
Molecules ; 27(23)2022 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-36500602

RESUMEN

Matricaria recutita L., German chamomile, is one of the most widely used medicinal plants, whose efficacy has been proven in numerous studies. However, its roots have attracted only little interest so far, since mainly above-ground plant parts are used for medicinal purposes. To broaden the knowledge of chamomile roots, a profound phytochemical characterization was performed along with a bioactivity screening of corresponding root extracts. While volatile constituents such as chamomillol and polyynes were detected using GC-MS, HPLC-MSn analyses revealed the occurrence of four coumarin glycosides, more than ten phenolic acid esters and five glyceroglycolipids. Furthermore, the antioxidant activity of the extracts was evaluated. Polar extracts revealed IC50 values ranging from 13 to 57 µg/mL in the DPPH radical scavenging assay, which is in the same range as reported for chamomile flower extracts. In addition, superoxide radical scavenging potential and mild antibacterial effects against S. aureus und B. subtilis were demonstrated. Moreover, to assess interspecies variation in chamomile roots, extracts of M. recutita were compared to those of M. discoidea DC. Interestingly, the latter revealed stronger antioxidant activity. The presented results aim at the valorization of chamomile roots, previously discarded as by-product of chamomile flower production, as a sustainable source of bioactive phytochemicals.


Asunto(s)
Matricaria , Aceites Volátiles , Matricaria/química , Antioxidantes/farmacología , Staphylococcus aureus , Aceites Volátiles/química , Fitoquímicos/farmacología , Extractos Vegetales/farmacología , Extractos Vegetales/química
10.
J Biol Chem ; 295(44): 14987-14997, 2020 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-32848020

RESUMEN

Rapid diagnostic tests are first-line assays for diagnosing infectious diseases, such as malaria. To minimize false positive and false negative test results in population-screening assays, high-quality reagents and well-characterized antigens and antibodies are needed. An important property of antigen-antibody binding is recognition specificity, which best can be estimated by mapping an antibody's epitope on the respective antigen. We have cloned a malarial antigen-containing fusion protein, MBP-pfMSP119, in Escherichia coli, which then was structurally and functionally characterized before and after high pressure-assisted enzymatic digestion. We then used our previously developed method, intact transition epitope mapping-targeted high-energy rupture of extracted epitopes (ITEM-THREE), to map the area on the MBP-pfMSP119 antigen surface that is recognized by the anti-pfMSP119 antibody G17.12. We identified three epitope-carrying peptides, 386GRNISQHQCVKKQCPQNSGCFRHLDE411, 386GRNISQHQCVKKQCPQNSGCFRHLDEREE414, and 415CKCLLNYKQE424, from the GluC-derived peptide mixture. These peptides belong to an assembled (conformational) epitope on the MBP-pfMSP119 antigen whose identification was substantiated by positive and negative control experiments. In conclusion, our data help to establish a workflow to obtain high-quality control data for diagnostic assays, including the use of ITEM-THREE as a powerful analytical tool. Data are available via ProteomeXchange: PXD019717.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Antígenos de Protozoos/inmunología , Epítopos/inmunología , Malaria Falciparum/inmunología , Proteína 1 de Superficie de Merozoito/inmunología , Secuencia de Aminoácidos , Animales , Complejo Antígeno-Anticuerpo/inmunología , Western Blotting , Electroforesis en Gel de Poliacrilamida/métodos , Mapeo Epitopo/métodos , Espectrometría de Masa por Ionización de Electrospray/métodos
11.
Int J Mol Sci ; 22(10)2021 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-34068052

RESUMEN

Splicing is an important RNA processing step. Genetic variations can alter the splicing process and thereby contribute to the development of various diseases. Alterations of the splicing pattern can be examined by gene expression analyses, by computational tools for predicting the effects of genetic variants on splicing, and by splicing reporter minigene assays for studying alternative splicing events under defined conditions. The minigene assay is based on transient transfection of cells with a vector containing a genomic region of interest cloned between two constitutive exons. Cloning can be accomplished by the use of restriction enzymes or by site-specific recombination using Gateway cloning. The vectors pDESTsplice and pSpliceExpress represent two minigene systems based on Gateway cloning, which are available through the Addgene plasmid repository. In this review, we describe the features of these two splicing reporter minigene systems. Moreover, we provide an overview of studies in which determinants of alternative splicing were investigated by using pDESTsplice or pSpliceExpress. The studies were reviewed with regard to the investigated splicing regulatory events and the experimental strategy to construct and perform a splicing reporter minigene assay. We further elaborate on how analyses on the regulation of RNA splicing offer promising prospects for gaining important insights into disease mechanisms.


Asunto(s)
Empalme Alternativo , Clonación Molecular , Genes Reporteros , Enfermedades Genéticas Congénitas/diagnóstico , Vectores Genéticos/genética , Genoma Humano , Mutación , Enzimas de Restricción del ADN , Enfermedades Genéticas Congénitas/genética , Humanos
12.
Molecules ; 26(6)2021 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-33799635

RESUMEN

In the present study, Achillea atrata L. and A. millefolium L. were compared for the first time with regard to their phenolic compound profile and antioxidant activity by applying the 2,2-diphenyl-picryl hydrazyl radical assay. For this purpose, aerial plant parts were consecutively extracted with solvents of increasing polarity (dichloromethane, n-butanol, ethyl acetate), revealing that the A. atrata ethyl acetate fraction showed the highest antioxidant activity with an IC50 value of 12.2 ± 0.29 µg/mL compared to 17.0 ± 0.26 µg/mL for A. millefolium. Both species revealed the presence of luteolin, apigenin, centaureidin, and nevadensin exclusively in this most polar fraction, which are known as effective 2,2-diphenyl-picryl hydrazyl radical scavengers. The antioxidant capacity of the aforementioned fractions strikingly correlated with their total phenolic contents, which was highest in the ethyl acetate fraction of A. atrata. Characterization of the metabolite profiles of both Achillea species showed only marginal differences in the presence of key compounds, whereas the concentrations of individual compounds appeared to be species-specific. Our results suggest that A. atrata, based on its compound pattern and bioactivity characteristics, has similar qualities for phytotherapy as A. millefolium.


Asunto(s)
Achillea/química , Achillea/metabolismo , Fenoles/análisis , Antioxidantes/química , Apigenina , Flavonas , Flavonoides , Luteolina , Fenoles/química , Componentes Aéreos de las Plantas/química , Extractos Vegetales/química , Solventes
13.
Chem Biodivers ; 17(4): e1900724, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32096590

RESUMEN

The investigations reported here focus on an in-depth characterization of the secondary metabolite profile of Sanguisorba officinalis flowers. For this purpose, fresh flowers were extracted with MeOH/H2 O and EtOH/H2 O and the resulting crude extracts fractionated using CH2 Cl2 , AcOEt, and BuOH. Individual compounds were characterized by high performance liquid chromatography and gas chromatography coupled with mass spectrometric detection (HPLC-DAD-MSn and GC/MS). MeOH/H2 O extraction and LC/MSn investigations revealed the occurrence of flavonoid glycosides (quercetin, kaempferol), ellagitannin glycosides and four anthocyanins. Among the latter, two components, i. e., cyanidin-malonyl-glucose and cyanidin-galloyl-hexose, have not been reported for S. officinalis so far. Furthermore, phenylethylamine was characterized for the first time in Sanguisorba by pH value dependent extraction with CH2 Cl2 . In addition, AcOEt and BuOH extracts were analyzed by GC/MS both prior to and after acid hydrolysis of secondary metabolites. For this purpose, the extracts were treated with 1 n HCl solution (105 °C, 1 h) and derivatized with BSTFA. Analyses revealed the occurrence of several classes of phenolic compounds, such as gallic acid, hydroxybenzoic acid, hydroxycinnamic acid and ellagic acid derivatives. Additionally, the most prominent ursane-type triterpenoid (ziyu-glycoside I) from Sanguisorba and its corresponding aglycone isomers were detected and assigned based on their characteristic fragmentation patterns.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas , Sanguisorba/química , Espectrometría de Masas en Tándem , Aminas/análisis , Aminas/química , Aminas/metabolismo , Antocianinas/análisis , Antocianinas/química , Antocianinas/metabolismo , Cromatografía Líquida de Alta Presión , Flores/química , Flores/metabolismo , Glicósidos/análisis , Glicósidos/química , Glicósidos/metabolismo , Isomerismo , Fenoles/análisis , Fenoles/química , Fenoles/metabolismo , Extractos Vegetales/química , Sanguisorba/metabolismo
14.
Chem Biodivers ; 17(10): e2000485, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32860459

RESUMEN

Extracts of kidney vetch (Anthyllis vulneraria L.) are becoming increasingly interesting as ingredients for the health and cosmetics industry. However, comprehensive phytochemical investigations of this plant are scant in the literature. Thus, the aim of the present work was an in-depth characterization of semi-polar constituents from A. vulneraria. To capture a broad spectrum of compounds, the aerial parts of A. vulneraria were extracted with EtOH/water and the resulting crude extracts fractionated by partition between AcOEt and BuOH. Secondary plant metabolites were analyzed by HPLC-ESI-MSn and GC/MS. In a fraction obtained from the BuOH extract via Amberlite® XAD-7 purification glycosides of kaempferol, quercetin, isorhamnetin and rhamnocitrin were detected by LC/MSn , besides flavonoids acylated with meglutol (3-hydroxy-3-methylglutaric acid), acetic and ferulic acids. Moreover, aglycons were analyzed in extracts after 1 N HCl hydrolysis and derivatization with BSTFA. GC/MS analysis of the hydrolysates revealed the incidence of compounds like meglutol, OH/OMe-substituted benzoic acids, ferulic and fatty acids, flavonoids, sugars and the triterpenoid medicagenic acid. Furthermore, a hemolytic activity was detected in the AcOEt extract using a blood-agar assay, and this was ascribed to the occurrence of saponins. In a saponin fraction, obtained from the AcOEt extract by chromatographic purification, two main saponins were characterized by LC/MSn and HR-ESI-MSn . A pure sapogenin could be isolated via VLC and CC purification upon acid hydrolysis of the saponins and assigned to saikogenin D by NMR analysis.


Asunto(s)
Fabaceae/química , Fitoquímicos/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Medicina de Hierbas , Estructura Molecular , Fitoquímicos/química , Extractos Vegetales/química , Espectrometría de Masa por Ionización de Electrospray
15.
Mol Cell Proteomics ; 15(4): 1360-80, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26831522

RESUMEN

Intrathecal immunoglobulin G (IgG) synthesis and oligoclonal IgG bands in cerebrospinal fluid (CSF) are hallmarks of multiple sclerosis (MS), but the antigen specificities remain enigmatic. Our study is the first investigating the autoantibody repertoire in paired serum and CSF samples from patients with relapsing-remitting MS (RRMS), primary progressive MS (PPMS), and other neurological diseases by the use of high-density peptide microarrays. Protein sequences of 45 presumed MS autoantigens (e.g.MOG, MBP, and MAG) were represented on the microarrays by overlapping 15mer peptides. IgG reactivities were screened against a total of 3991 peptides, including also selected viral epitopes. The measured antibody reactivities were highly individual but correlated for matched serum and CSF samples. We found 54 peptides to be recognized significantly more often by serum or CSF antibodies from MS patients compared with controls (pvalues <0.05). The results for RRMS and PPMS clearly overlapped. However, PPMS patients presented a broader peptide-antibody signature. The highest signals were detected for a peptide mapping to a region of the Epstein-Barr virus protein EBNA1 (amino acids 392-411), which is homologous to the N-terminal part of human crystallin alpha-B. Our data confirmed several known MS-associated antigens and epitopes, and they delivered additional potential linear epitopes, which await further validation. The peripheral and intrathecal humoral immune response in MS is polyspecific and includes antibodies that are also found in serum of patients with other diseases. Further studies are required to assess the pathogenic relevance of autoreactive and anti-EBNA1 antibodies as well as their combinatorial value as biomarkers for MS.


Asunto(s)
Autoanticuerpos/sangre , Autoanticuerpos/líquido cefalorraquídeo , Esclerosis Múltiple Crónica Progresiva/inmunología , Esclerosis Múltiple Recurrente-Remitente/inmunología , Péptidos/metabolismo , Adulto , Especificidad de Anticuerpos , Autoanticuerpos/metabolismo , Autoantígenos/química , Autoantígenos/metabolismo , Femenino , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina G/líquido cefalorraquídeo , Inmunoglobulina G/metabolismo , Masculino , Análisis por Micromatrices/métodos , Persona de Mediana Edad
16.
Chem Biodivers ; 15(5): e1800035, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29575712

RESUMEN

Seeds from Hypericum species have recently been identified as an interesting source of xanthone derivatives. Extraction of seeds from H. perforatum with MeOH and subsequent concentration via polyamide adsorption yielded a fraction enriched in tetrahydroxyxanthones (THX), which were further semipurified by silica gel chromatography. Based on tentative structure assignment of the two main THX X1 and X2 by NMR a total synthesis was performed for both compounds (THX 1 and 2, respectively), starting with an Ullmann ether synthesis. The synthesized 1 and 2 were characterized via 1D- and 2D-NMR methods as well as by LC/HR-MS analysis and proven to be 1,4,6,7-THX (1) and 1,2,6,7-THX (2). Final structure assignment of the natural Hypericum THX constituents was accomplished by comparing chromatographic and spectroscopic data (LC/MSn and GC/MS) with those of 1 and 2 which were obtained by synthesis. Beyond, investigations into the seeds of H. perforatum and H. tetrapterum by scanning electron microscopy (SEM) provided insights of the structure of the testa (seed coat), which is established by two cell layers, with the lignified sclerenchyma presumably being the depository of the xanthones.


Asunto(s)
Hypericum/química , Xantonas/química , Estructura Molecular , Extractos Vegetales/química , Semillas/química , Xantonas/síntesis química , Xantonas/aislamiento & purificación
17.
Chem Biodivers ; 14(2)2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28134470

RESUMEN

Mercurialis tomentosa L. has been used in Spanish ethnomedicine. In the present study the first phytochemical characterisation of a lipid fraction from M. tomentosa was performed. The CHCl3 extraction of aerial parts from M. tomentosa and GC/MS investigations revealed the occurrence of cuticular lipid and wax constituents, like long chain n-alcohols and n-aldehydes (C22  - C30 ), besides several aromatic constituents, i.e., phenylpropanoids and n-alkylresorcinols. The latter were further purified by CC and analysed by LC/MSn . In contrast to other Mercurialis species, i.e., M. annua, M. perennis, which exclusively contain 5-n-alkylresorcinols (1a - j, Cn ), mainly 5-n-alkyl-2-methylresorcinols (2a - j, Cn *) with side chain lengths of C15  - C25 were found in M. tomentosa, in addition to 1a - j. Thus, the latter compounds may be utilised for analytical characterisation and authentication of M. tomentosa based on fingerprinting methods. For structure elucidation a novel facile total synthesis of one representative 5-n-alkyl-2-methylresorcinol homologue (2d, C19 *) was developed, starting with a Grignard reaction from a substituted benzoic acid chloride (19). The compound obtained by synthesis was identical to the natural product 2d in terms of its chromatographic and spectroscopic features. Futhermore, 2d exhibited satisfactory DPPH free radical scavenging activity (IC50  = 37.8 µm) when compared to trolox (IC50  = 21.0 µm), corroborating the antioxidant features of these amphipathic molecules.


Asunto(s)
Antioxidantes/farmacología , Euphorbiaceae/química , Lípidos/análisis , Extractos Vegetales/análisis , Resorcinoles/análisis , Cromatografía de Gases y Espectrometría de Masas , Lípidos/química , Extractos Vegetales/química , Resorcinoles/química , España
18.
Chem Biodivers ; 14(8)2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28557380

RESUMEN

Seeds of Hypericum perforatum and H. tetrapterum were extracted with dichloromethane and methanol and investigated by chromatographic and mass spectrometric methods. Both species yielded a fatty oil fraction amounting to 30.5% and 18.0% of the seed weight, respectively. Linoleic acid (C18:2n-6) was shown to be the predominant fatty acid constituent. Moreover, xanthone derivatives, i.e. tetrahydroxyxanthones (THX), xanthone-glycosides and xanthone-sulfonates, were assigned in methanolic extracts. For structure elucidation, one representative xanthone, namely 1,3,6,7-THX, was synthesized and analyzed via HPLC-DAD/MSn and GC/MS. Total THX contents were quantitated applying a validated HPLC-DAD method, resulting in 1.25 g/kg (H. perforatum) and 0.27 g/kg (H. tetrapterum), respectively. Moreover, the free radical scavenging capacity of the methanol extracts was tested using the DPPH antioxidant assay. Both, H. perforatum (IC50 = 8.7 mg/l) and 1,3,6,7-THX (IC50 = 3.0 mg/l), exhibited good DPPH free radical scavenging activity compared to Trolox (IC50 = 6.6 mg/l).


Asunto(s)
Hypericum/química , Lípidos/química , Lípidos/farmacología , Fenoles/química , Fenoles/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Hypericum/metabolismo , Lípidos/análisis , Espectroscopía de Resonancia Magnética , Oxidación-Reducción/efectos de los fármacos , Fenoles/análisis , Semillas/química , Semillas/metabolismo , Espectrometría de Masa por Ionización de Electrospray , Xantonas/análisis , Xantonas/química , Xantonas/farmacología
19.
BMC Bioinformatics ; 17: 155, 2016 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-27059896

RESUMEN

BACKGROUND: Understanding the interactions between antibodies and the linear epitopes that they recognize is an important task in the study of immunological diseases. We present a novel computational method for the design of linear epitopes of specified binding affinity to Intravenous Immunoglobulin (IVIg). RESULTS: We show that the method, called Pythia-design can accurately design peptides with both high-binding affinity and low binding affinity to IVIg. To show this, we experimentally constructed and tested the computationally constructed designs. We further show experimentally that these designed peptides are more accurate that those produced by a recent method for the same task. Pythia-design is based on combining random walks with an ensemble of probabilistic support vector machines (SVM) classifiers, and we show that it produces a diverse set of designed peptides, an important property to develop robust sets of candidates for construction. We show that by combining Pythia-design and the method of (PloS ONE 6(8):23616, 2011), we are able to produce an even more accurate collection of designed peptides. Analysis of the experimental validation of Pythia-design peptides indicates that binding of IVIg is favored by epitopes that contain trypthophan and cysteine. CONCLUSIONS: Our method, Pythia-design, is able to generate a diverse set of binding and non-binding peptides, and its designs have been experimentally shown to be accurate.


Asunto(s)
Biología Computacional/métodos , Epítopos/química , Inmunoglobulinas Intravenosas/química , Péptidos Cíclicos/química , Citrulina/química , Cisteína/química , Humanos , Modelos Moleculares , Reproducibilidad de los Resultados , Máquina de Vectores de Soporte , Triptófano/química
20.
Chem Biodivers ; 13(5): 602-12, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27039891

RESUMEN

Five homologous acetylated acylglycerols of 3-hydroxyfatty acids (chain lengths C(14) - C(18)), named euphrasianins A - E, were characterized for the first time in Euphrasia rostkoviana Hayne (Orobanchaceae) by gas chromatography/mass spectrometry (GC/MS) and high-performance liquid chromatography/atmospheric pressure chemical ionization-mass spectrometry (HPLC/APCI-MS(n) ). In addition to mass spectrometric data, structures of euphrasianins were verified via a three-step total synthesis of one representative homologue (euphrasianin A). The structure of the latter was confirmed by 1D- and 2D-NMR experiments as well as high-resolution electrospray ionization-mass spectrometry (HR-ESI-MS). The absolute configuration of the 3-hydroxyfatty acid moiety at C(3) was found to be R in the natural euphrasianins, which was determined by alkaline hydrolysis and methylation of a purified fraction, followed by chiral GC analysis. Furthermore, in extracts of Euphrasia tetraquetra (Bréb.) Arrond. euphrasianins C and E were detected exclusively, indicating that this subclass of lipid constituents is possibly valuable for fingerprinting methods.


Asunto(s)
Euphrasia/química , Glicerol/análogos & derivados , Glicerol/aislamiento & purificación , Lípidos/aislamiento & purificación , Orobanchaceae/química , Extractos Vegetales/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Glicerol/química , Lípidos/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Extractos Vegetales/química , Espectrometría de Masa por Ionización de Electrospray
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