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1.
J Med Virol ; 95(1): e28268, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36319593

RESUMEN

We have measured the humoral response to messenger RNA (mRNA) vaccines in COVID-19 naïve and convalescent individuals. Third doses of mRNA COVID-19 vaccines induced a significant increase in potency and breadth of neutralization against SARS-CoV-2 variants of concern (VoC) including Omicron subvariants BA.1, BA.2, and BA.2.12.1, that were cross-neutralized at comparable levels and less for BA.4/5. This booster effect was especially important in naïve individuals that only after the third dose achieved a level that was comparable with that of vaccinated COVID-19 convalescents except for BA.4/5. Avidity of RBD-binding antibodies was also significantly increased in naïve individuals after the third dose, indicating an association between affinity maturation and cross neutralization of VoC. These results suggest that at least three antigenic stimuli by infection or vaccination with ancestral SARS-CoV-2 sequences are required to induce high avidity cross-neutralizing antibodies. Nevertheless, the circulation of new subvariants such as BA.4/5 with partial resistance to neutralization will have to be closely monitored and eventually consider for future vaccine developments.


Asunto(s)
COVID-19 , Humanos , COVID-19/prevención & control , Vacunas contra la COVID-19 , SARS-CoV-2/genética , ARN Mensajero/genética , Vacunas de ARNm , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Glicoproteína de la Espiga del Coronavirus
2.
J Med Virol ; 95(11): e29225, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37971751

RESUMEN

Currently, the majority of the population has been vaccinated against COVID-19 and/or has experienced SARS-CoV-2 infection either before or after vaccination. The immunological response to repeated episodes of infections is not completely clear. We measured SARS-CoV-2 specific neutralization titers by a pseudovirus assay after BA.1 infection and RBD-specific immunoglobulin G (IgG), immunoglobulin A (IgA), and immunoglobulin M (IgM) in a cohort of COVID-19 uninfected and triple vaccinated individuals (breakthrough infection group, BTI) as compared with those previously infected by SARS-CoV-2 (reinfection group, REI) who underwent identical vaccination schedule. SARS-CoV-2 specific neutralizing response after BA.1 infection was significantly higher in the BTI group as compared with the REI. Furthermore, neutralization titers in REI were not significant different from convalescent non reinfected controls. RBD-specific IgG and IgA, but not IgM, were also significantly higher in BTI as compared with REI. Our results show that the first episode of SARS-CoV-2 infection induces a significant increase in neutralizing titers in triple vaccinated individuals and that previous SARS-CoV-2 infection compromise significantly the neutralization response induced by reinfection, even by divergent SARS-CoV-2 variants and at least up to 2 years postinfection, suggesting a fundamental limitation in inducing effective booster through the intranasal route in previously infected individuals.


Asunto(s)
COVID-19 , Humanos , COVID-19/prevención & control , SARS-CoV-2 , Reinfección , Inmunoglobulina A , Inmunoglobulina G , Inmunoglobulina M , Vacunación , Anticuerpos Neutralizantes , Anticuerpos Antivirales
3.
J Infect Dis ; 225(11): 1905-1908, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-34963008

RESUMEN

We have investigated the evolution of the neutralizing response against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants at 8 months after Pfizer-BNT162b2 vaccination in coronavirus disease 2019 (COVID-19)-naive (n = 21) and COVID-19-convalescent (n = 21) individuals. Neutralizing levels declined for all variants (range 2- to 3.7-fold). Eight months after vaccination, a significant proportion (4/21) of naive individuals lacked detectable neutralizing activity against the highly transmissible SARS-CoV-2 delta variant. In the convalescent group, the impressive high initial humoral response resulted in detectable neutralizing antibody levels against all variants throughout this period.


Asunto(s)
COVID-19 , SARS-CoV-2 , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Vacuna BNT162 , COVID-19/prevención & control , Humanos , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus , Vacunación
4.
Nutr Cancer ; 70(2): 267-277, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29266974

RESUMEN

Dietary phenolic compounds are plant metabolites with beneficial effects on the central nervous system. Thus, our aim was to identify anti-inflammatory compounds from South American plants on glia, which regulates neuro-immune response. The compounds were extracted from Lantana grisebachii (LG), Aspidosperma quebracho-blanco (AQB), and Ilex paraguariensis (IP) teas and identified by HPLC-DAD-MS. Extracts (0-200 µg/ml) were tested on human T98-G and rat C6 glioma lines. Cellular viability (by the resazurin assay), fatty acid profile (by gas chromatography) and pro-inflammatory interleukin-6 release (IL-6 by ELISA) were determined. Data were analyzed by partial least-square regression to discriminate bioactive compounds. Twenty-one compounds were determined in LG, mainly iridoids, which were linked to ω-3 and ω-6 polyunsaturated fatty acids, but not to IL-6 release. Thirty-one compounds were found in AQB, mostly hydroxybenzoic derivatives, which were positively related to IL-6 release. Twenty-three compounds were identified in IP, including caffeoylquinic derivatives and mainly chlorogenic acid. They increased the ω-7 palmitoleic fatty acid, which was related to IL-6 decrease. These results enhances phytochemical knowledge of widely available plants, and suggest the lipid-related anti-inflammatory activity of IP phenolic compounds, which give nutritional relevance to the tea.


Asunto(s)
Ácidos Grasos/metabolismo , Fenoles/análisis , Extractos Vegetales/farmacología , Tés de Hierbas/análisis , Animales , Aspidosperma/química , Línea Celular Tumoral , Glioma/tratamiento farmacológico , Glioma/metabolismo , Glioma/patología , Humanos , Ilex paraguariensis/química , Interleucina-6/metabolismo , Lantana/química , Fenoles/farmacología , Extractos Vegetales/química , Ratas , América del Sur
5.
J Sci Food Agric ; 97(12): 4066-4074, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28397240

RESUMEN

BACKGROUND: The phenolic composition of grapes is key when making decisions about harvest date and ensuring the quality of grapes. The present study aimed to investigate the relationship between the detailed phenolic composition of grapes and the agronomic parameters and hyperspectral indices, with the latter being measured via field radiometry techniques. RESULTS: Good correlations were found between phenolic composition (both anthocyanin and flavanol composition) and some hyperspectral indices related to vigor, such as the NDVI (normalized difference vegetation index) and the SAVI (soil adjusted vegetation index). The strongest correlations were observed between the phenolic composition of grape skin at harvest time and variables measured from grapes at veraison time, as well as variables determined from grapevines at harvest time. The potential usefulness of these hyperspectral indices calculated from measurements performed directly on grapes or grapevines for estimating the anthocyanin and flavanol composition of grape skins was indicated by the high coefficients of determination (R2 = 0.7955 and R2 = 0.8594, respectively) as obtained by means of principal component regression. CONCLUSION: According to the results of the present study, hyperspectral indices calculated from measurements performed directly on grapes at veraison time or on grapevines at harvest time may be useful for estimating the anthocyanin and flavanol composition of grape skins. This suggests that field radiometry might provide valuable information for estimating the phenolic composition of grapes, which may prove to be very useful when establishing strategies for harvest planning. © 2017 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Asunto(s)
Fenoles/química , Extractos Vegetales/química , Vitis/química , Agricultura , Frutas/química , Frutas/crecimiento & desarrollo , Suelo/química , Vitis/crecimiento & desarrollo
6.
Chem Senses ; 40(6): 381-90, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25934978

RESUMEN

In this work, sensations elicited by catechin and procyanidins in comparison with those elicited by gallocatechin and prodelphinidins were evaluated by means of a sensory panel. To obtain further insights into the mechanisms of action, molecular dynamics (MD) simulations and saturation transfer difference nuclear magnetic resonance (STD NMR) experiments have been performed. Results showed clear differences between the 2 types of flavanols. Dihydroxylated B-ring flavanols were more astringent, bitter, dry, rough, unripe, and persistent than trihydroxylated B-ring ones. Besides, these last compounds were smoother, more velvety, and viscous. MD simulations and STD NMR experiments support results obtained from tasting panel. MD results suggested that catechin binds to a human salivary proline-rich peptide IB714 faster than gallocatechin and this interaction is maintained longer. IB714 can interact with 2 catechin molecules concurrently while only interacts with 1 gallocatechin molecule. Accordingly, STD NMR experiments showed a greater affinity of catechin than gallocatechin for the peptide (K D = 2.7 and 25.7, respectively). Results indicate that the number of hydroxyl substituents present in B-ring of the flavanic nucleus is decisive for the interaction with salivary proteins and the development of astringency perception.


Asunto(s)
Catequina/análogos & derivados , Catequina/química , Simulación de Dinámica Molecular , Resonancia Magnética Nuclear Biomolecular , Proteínas y Péptidos Salivales/química , Sitios de Unión , Catequina/metabolismo , Humanos , Cinética , Polifenoles/química , Polifenoles/metabolismo , Análisis de Componente Principal , Unión Proteica , Proteínas y Péptidos Salivales/metabolismo
7.
Langmuir ; 31(30): 8392-401, 2015 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-26162056

RESUMEN

The interaction between phenolic compounds and salivary proteins is considered the basis of the poorly understood phenomenon of astringency. Furthermore, this interaction is an important factor in relation to their bioavailability. In this work, interactions between anthocyanin and human salivary protein fraction were studied by mass spectrometry (MALDI-TOF-MS and FIA-ESI-MS) and saturation-transfer difference (STD) NMR spectroscopy. Anthocyanins were able to interact with saliva proteins. The dissociation constant (KD) between malvidin 3-glucoside and salivary proline-rich proteins was 1.92 mM for the hemiketal form (pH 3.4) and 1.83 mM for the flavylium cation (pH 1.0). New soluble complexes between these salivary proteins and malvidin 3-glucoside were identified for the first time.


Asunto(s)
Antocianinas/química , Proteínas y Péptidos Salivales/química , Adulto , Femenino , Voluntarios Sanos , Humanos , Espectroscopía de Resonancia Magnética , Masculino , Espectrometría de Masas , Adulto Joven
8.
J Sci Food Agric ; 93(4): 967-72, 2013 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-23080075

RESUMEN

BACKGROUND: Interest in high-quality products with a clear geographical origin is increasing. For the wine industry and market sector, identity preservation is of fundamental importance owing to the large number of geographical classifications. Nowadays, there is a growing demand for analytical methods for tracing grapes and wines. In the oenological sector, infrared spectroscopy is becoming an attractive tool allowing simultaneous measurement of several analytical parameters and enabling real-time decision making. RESULTS: Discriminant partial least squares, a supervised pattern recognition technique, was employed to discriminate between vineyards of origin using the near-infrared spectra of intact grapes, skins or seeds. In order to compare the three sample presentations, a receiver operating characteristic curve was used. The best results were obtained using intact grape seeds, with prediction rates of samples correctly classified of about 95%, although the good results obtained with entire grapes (about 93% of samples correctly classified) and the simplicity of use of the fibre optic probe could advise using entire grape presentation for comprehensive studies. CONCLUSION: The procedure reported here seems to have excellent potential for a fast and reasonably inexpensive analysis of the origin of samples. It is noted that such classification can be made at any time of ripening. This paper provides information of interest to develop new and extensive models in the future.


Asunto(s)
Frutas , Preparaciones de Plantas , Semillas , Espectroscopía Infrarroja Corta/métodos , Vitis , Vino/análisis , Tecnología de Fibra Óptica , Análisis de los Mínimos Cuadrados , Curva ROC
9.
Proc Inst Mech Eng H ; 237(5): 552-556, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37052168

RESUMEN

According to the recommendations by the World Health Organization, the insertion of a peripheral venous catheter (PVC) must be an aseptic procedure while using non-sterile gloves. To overcome this apparent contradiction we have invented and patented (WO/2021/123482) a new device to be used during PVC insertion. The device permits the PVC placement in the vein while avoiding to directly touch the catheter with the fingertips. A total of 16 PVCs were inserted in the veins of a venipuncture anatomic training model while the operator was wearing non-sterile gloves. The gloves had been previously contaminated by embedding the fingertips in an agar plate inoculated with Staphylococcus epidermidis. Following insertion, the PVCs were sterilely removed and deposited on a bacterial culture plate. The tip cultures of PVCs that had been inserted with or without the use of the device were compared. Eight out of eight cultures (100.0%) were positive for S. epidermidis when the PVC had been inserted without using the device, whereas only one out of eight (12.5%) was positive when the device had been used. The single positive tip culture in the latter group corresponded to an insertion in which the operator had inadvertently touched the sterile part of the device while manipulating it. In conclusion, an auxiliary novel device allows the aseptic insertion of PVCs while the operator is wearing non-sterile gloves. Regulatory institutions should consider to recommend the insertion of PVCs by means of devices aimed at avoiding the contamination of the catheter.


Asunto(s)
Cateterismo Periférico , Catéteres , Venas
10.
Arch Dis Child ; 107(11): 1051-1058, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35688603

RESUMEN

OBJECTIVES: To evaluate the performance of oral saliva swab (OSS) reverse transcription PCR (RT-PCR) compared with RT-PCR and antigen rapid diagnostic test (Ag-RDT) on nasopharyngeal swabs (NPS) for SARS-CoV-2 in children. DESIGN: Cross-sectional multicentre diagnostic study. SETTING: Study nested in a prospective, observational cohort (EPICO-AEP) performed between February and March 2021 including 10 hospitals in Spain. PATIENTS: Children from 0 to 18 years with symptoms compatible with Covid-19 of ≤5 days of duration were included. Two NPS samples (Ag-RDT and RT-PCR) and one OSS sample for RT-PCR were collected. MAIN OUTCOME: Performance of Ag-RDT and RT-PCR on NPS and RT-PCR on OSS sample for SARS-CoV-2. RESULTS: 1174 children were included, aged 3.8 years (IQR 1.7-9.0); 73/1174 (6.2%) patients tested positive by at least one of the techniques. Sensitivity and specificity of OSS RT-PCR were 72.1% (95% CI 59.7 to 81.9) and 99.6% (95% CI 99 to 99.9), respectively, versus 61.8% (95% CI 49.1 to 73) and 99.9% (95% CI 99.4 to 100) for the Ag-RDT. Kappa index was 0.79 (95% CI 0.72 to 0.88) for OSS RT-PCR and 0.74 (95% CI 0.65 to 0.84) for Ag-RDT versus NPS RT-PCR. CONCLUSIONS: RT-PCR on the OSS sample is an accurate option for SARS-CoV-2 testing in children. A less intrusive technique for younger patients, who usually are tested frequently, might increase the number of patients tested.


Asunto(s)
COVID-19 , Niño , Humanos , COVID-19/diagnóstico , SARS-CoV-2/genética , Prueba de COVID-19 , Saliva , Transcripción Reversa , Estudios Prospectivos , Estudios Transversales , Sensibilidad y Especificidad , Reacción en Cadena de la Polimerasa
11.
Open Forum Infect Dis ; 8(10): ofab468, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34642637

RESUMEN

BACKGROUND: The objective of this study was to investigate the neutralizing response against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VoC) during coronavirus disease 2019 (COVID-19) convalescence and after vaccination. METHODS: COVID-19-convalescent and -naïve individuals were tested for neutralizing activity against SARS-CoV-2 VoC Alpha, Beta, Gamma, and Delta at 1 and 7 months postinfection and 4-6 weeks after BNT162b2 vaccination. RESULTS: Vaccination induced a high neutralizing response in naïve individuals. Interestingly, vaccination of convalescent patients induced a boosted response that was able to neutralize all VoC at high titers. CONCLUSIONS: Vaccination with BNT162b2 induced high levels of neutralization against SARS-CoV-2 VoC in most patients; this is especially beneficial in COVID-19-convalescent individuals.

12.
FEMS Yeast Res ; 10(7): 858-69, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20846146

RESUMEN

Polyphenols are considered to be responsible for some of the health benefits derived from the consumption of red wine. These protective effects might probably be explained in the context of the xenohormesis theory that considers plant metabolites as interspecific chemical signals. However, the complexity of the polyphenolic constituents of different wines makes it difficult to clarify the specific contribution of polyphenols to such effects. In the present work, we fractionated the polyphenols of a red wine and evaluated the effect of each polyphenolic fraction on the growth pattern of the yeast Saccharomyces cerevisiae. We observed a different contribution of the phenolic fractions to the xenohormetic response of S. cerevisiae, the fractions that were enriched with red pigments being the most protective against oxidative insults. Moreover, we found that red wine phenolic fractions exert their biological activity through the activation of the Yap1 and Msn2 stress-responsive regulators. Above all, the anthocyanins delphinidin 3-glucoside and petunidin 3-glucoside were found to improve significantly the growth rate of S. cerevisiae in an Msn2-, Msn4-dependent manner, indicating that the stress regulators Msn2 and Msn4 participate in the xenohormetic activity of the wine polyphenols delphinidin and petunidin.


Asunto(s)
Antocianinas/farmacología , Antioxidantes/farmacología , Proteínas de Unión al ADN/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/efectos de los fármacos , Factores de Transcripción/metabolismo , Vino , Saccharomyces cerevisiae/crecimiento & desarrollo
13.
J Med Microbiol ; 69(12): 1373-1380, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33226321

RESUMEN

Introduction. Several studies have used matrix-assisted laser desorption ionization-time of flight MS (MALDI-TOF) with a serum separator tube (SST) to perform rapid identification of microorganisms directly from positive blood cultures (BCs), with different performances and methodologies.Hypothesis / Gap Statement. The use of TSS could significantly reduce the time of identification of microorganisms that produce bacteremia.Aim. Our goals were to evaluate bacterial identification by MALDI-TOF using a method based on an SST and compare it with MALDI-TOF after subculture for 18-24 h.Methodology. BCs no more than 1 h after a positive growth signal were included in the study. Analysis of results was expressed as a score. Information about time to a positive signal and number of microorganisms was collected.Results. In total, 253 BCs were analysed; 45.5 % gave a reliable result, 23.3 % an unreliable result and 31.2 % an error in identification. In gram-negative and gram-positive bacteria, the percentages of reliable results were 83.5 and 21.8 %, respectively. According to time to positive signal, the percentages of correct identification and mean score were 81.1 % (99/122) and 1.89±0.30 in Group 1 (<15 h); and 57.2 % (75/131) and 1.70±0.32 in Group 2 (>15 h), respectively (P <0.001). According to the number of microorganisms, the corresponding percentages of correct identification and mean scores were: Group 1 [≤50 microorganisms observed per field (MOF)], 50/94 (53.19 %) and 1.72±0.32; Group 2 (51-100 MOF): 44/66 (66.67 %) and 1.85±0.34; Group 3 (>100 MOF): 79/93 (84.94 %) and 1.84±0.31.Conclusion. This method allowed us to obtain a high percentage of the aetiological agent of bacteraemia in less than 30 min after a positive BC.


Asunto(s)
Bacterias/clasificación , Técnicas de Tipificación Bacteriana/métodos , Sangre/microbiología , Bacterias/aislamiento & purificación , Humanos , Estudios Prospectivos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Factores de Tiempo
14.
J Mass Spectrom ; 42(6): 735-48, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17511019

RESUMEN

High-pressure liquid chromatography-diode array detector-electrospray ionisation/ion trap mass spectrometry (HPLC-DAD-ESI/MS(n)) analyses carried out in red wine fractions revealed the existence of dimeric anthocyanins (A-A(+)), previously detected in grape skin, and allowed the detection and identification, for the first time, of other derived oligomers. The structure of these compounds was characterised according to their MS(n)(n = 1-4) fragmentation patterns. The newly detected oligomers consisted of a flavanol, (epi)catechin or (epi)gallocatechin, linked through its C(4) position to the nucleophilic positions of the upper unit of a dimeric anthocyanin (F-A-A(+)). All the compounds contained malvidin as one of the anthocyanin subunits, whereas the other anthocyanin moiety could be either delphinidin, cyanidin, petunidin, peonidin or malvidin. With the fractionation method employed, the dimeric anthocyanins eluted in the same fractions as the monomeric anthocyanins. However, the new F-A-A(+) oligomers were found in the same fractions as F-A(+) dimers, which might indicate a structural similarity between both types of compounds. ESI/MS(n) analyses, coupled or not to HPLC, showed to be a useful and powerful tool for detecting and identifying these oligomers in wines, which usually elute from reversed-phase columns as humps and/or are overlapped by the peaks of other compounds. The detection of these oligomeric pigments in wine has provided more information about the complex pigments responsible for the elevation of the base line observed in the chromatograms of wines and has also revealed that oligomeric anthocyanins can take part in the reactions usually undergone by monomeric anthocyanins.


Asunto(s)
Antocianinas/análisis , Cromatografía Líquida de Alta Presión , Espectrometría de Masa por Ionización de Electrospray/métodos , Vino/análisis , Antocianinas/química , Catequina/análogos & derivados , Catequina/análisis , Catequina/química , Dimerización , Estructura Molecular , Espectrometría de Masa por Ionización de Electrospray/instrumentación
15.
J Agric Food Chem ; 65(31): 6369-6378, 2017 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-28534630

RESUMEN

During the aging of red wine in oak wood barrels, or in alternative aging systems, interactions between the compounds released from wood, the compounds of the wine, and oxygen can take place. The main objective of the present work was to study oxygen-ellagitannin interactions by monitoring their levels in three model systems, all containing the same amounts of French oak chips and differing only in the oxygen content: total absence, only the oxygen released from the chips, and air-saturated (model systems F, OW, and OS, respectively). This study has highlighted the influence of oxygen in the ellagitannins' evolution and the relevance of the oxygen trapped into the oak chips, reporting for the first time the kinetics of oxygen release to the model wine. Furthermore, the indirect contribution of oxygen to the ellagitannins' disappearance by boosting autoxidative reactions has also been pointed out. Vescalagin seems to be the ellagitannin most affected by the initial oxygen levels.


Asunto(s)
Taninos Hidrolizables/química , Oxígeno/química , Quercus/química , Vino/análisis , Madera/química , Factores de Tiempo
16.
J Agric Food Chem ; 54(2): 536-42, 2006 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-16417317

RESUMEN

It has long been considered that the pigments resulting from direct condensation between anthocyanins and flavanols were formed exclusively during storage and processing, both in plant-derived foods and in drinks. Recently, however, the minor presence of this type of pigment has been shown in different plant extracts, among them beans. In this work we have studied this family of pigments in beans from Guatemala belonging to two distinct species of the genus Phaseolus, confirming the presence of (epi)gallocatechin carbon-carbon linked to the aglycone of delphinidin and (epi)catechin-cyanidin-3-glucoside. Furthermore, for the first time in this foodstuff another three flavanol-anthocyanin condensed pigments formed by the linkage of (epi)catechin with the corresponding aglycones of cyanidin, petunidin, and peonidin have been described. Also, the natural occurrence of anthocyanidins in this matrix has been confirmed in some of the samples analyzed in this work, the majority being components of their anthocyanin composition. The corresponding aglycones of delphinidin, cyanidin, petunidin, pelargonidin, and malvidin have been identified as well as two aglycones with identical mass to those of peonidin and petunidin, but with different retention times, which leads to the supposition that they are probably methylated derivatives of cyanidin and delphinidin, respectively.


Asunto(s)
Antocianinas/análisis , Antocianinas/química , Flavonoles/química , Phaseolus/química , Pigmentos Biológicos/química , Catequina/análogos & derivados , Catequina/química , Cromatografía Líquida de Alta Presión , Flavonoles/análisis , Guatemala , Espectrometría de Masas
17.
J Agric Food Chem ; 54(18): 6692-704, 2006 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-16939328

RESUMEN

Red wines made from Vitis vinifera L. cv. Tannat grapes are known to possess high contents of tannins and intense color, features that are responsible for the originality of these wines. This work aimed to study the evolution of the pigment composition and CIELAB color parameters as Tannat wines become older, as well as to establish the contribution to wine color of the main pigment families. Tannat wines produced in Uruguay from grapes of the same vineyard in six consecutive vintages (1998-2003) and Tannat grapes of the 2003 harvest were analyzed by means of HPLC-DAD-MS and UV-vis spectrometric techniques. The correlations between the different pigment families and the CIELAB parameters revealed the importance of the variations of the percentage, found in anthocyanins and flavanol-anthocyanin acetaldehyde-mediated condensation products (decrease) and pyranoanthocyanins and direct condensation products (increase), in the modification of the color from purple-red hues to more orange-red ones. The color suffered qualitative rather than quantitative changes, that is, the hue (h*ab) increased, whereas the chroma (C*ab) and lightness (L) did not show a defined trend with time.


Asunto(s)
Color , Pigmentos Biológicos/análisis , Vino/análisis , Cromatografía Líquida de Alta Presión , Frutas/química , Espectrometría de Masas , Factores de Tiempo , Vitis/química
18.
J Agric Food Chem ; 54(12): 4326-32, 2006 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-16756363

RESUMEN

An HPLC-MS method for the characterization of proanthocyanidins (PA) has been refined. Further application to red wines provided interesting conclusions about the composition of the flavanol fraction and PA extractability during winemaking. The yield in PA extraction increases with the length of the postfermentative maceration (PFM), as well as the mean degree of polymerization (mDP) of wine flavanols. In early winemaking events mostly monomers to trimers are extracted from grape solids, whereas PFM is required for the significant extraction of higher oligomers. Nevertheless, at the end of a regular process of elaboration the mDP is not very high and does not usually exceed a value of 2.3, dimers and trimers being the predominant flavanols in red wines. With regard to groups of compounds, gallocatechins and prodelphinidins (located in the skins) are extracted rapidly in the first stages of the winemaking. On the contrary, long postfermentative macerations are required for the extraction of galloyled derivatives from the seeds. PA extractability is also dependent on the grape variety used for winemaking. Thus, wines made with Graciano grapes were found to require a longer process of PFM than those made from Tempranillo grapes to obtain similar yields in the extraction of flavanols.


Asunto(s)
Cromatografía Líquida de Alta Presión , Espectrometría de Masas , Polímeros/análisis , Proantocianidinas/química , Vino/análisis , Fermentación , Flavonoides/análisis , Frutas/química , Polímeros/química , Proantocianidinas/análisis , Especificidad de la Especie , Factores de Tiempo , Vitis/química
19.
Drug Alcohol Rev ; 35(6): 673-677, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27072851

RESUMEN

INTRODUCTION AND AIMS: The Australian Treatment Outcomes Profile (ATOP) is a brief instrument that assesses a range of substance use, health and well-being measures over the past 28 days. Previously, it has been validated in general adult Australian alcohol and other drug (AOD) treatment populations. However, the increasing number of older-aged clients attending AOD treatment warrants the instrument to be validated for this population. The aim of this study was to validate the ATOP for use in older AOD populations, by comparing it with validated 'gold standard' measures used in older populations. DESIGN AND METHODS: A convenience sample of 99 participants aged ≥50 attending specialist AOD services in Sydney, Australia were administered the ATOP by a researcher, along with alcohol use (AUDIT) and health questionnaires [Physical Health Questionnaire-15, 12-item short-form Health Survey (SF-12) and Geriatric Depression Scale]. RESULTS: The ATOP items had strong agreement with the comparison instruments. The highest correlation was between the 28 days alcohol use and the AUDIT. ATOP psychological health scores highly correlated with the SF-12 mental health subscale and the Geriatric Depression Scale, and ATOP physical health scores significantly correlated with the SF-12 physical health subscale and the Physical Health Questionnaire-15. The ATOP Quality of Life score significantly correlated with all health measures. Discussion and Conclusions The ATOP has good concurrent validity with other validated substance use and health measures in an older population. Comparison with general older populations demonstrated the poorer health of this group of older AOD clients in particular.[Lintzeris N, Monds L A, Rivas G, Leung S, Withall A, Draper B. The Australian Treatment Outcomes Profile instrument as a clinical tool for older alcohol and other drug clients: A validation study. Drug Alcohol Rev 2016;35:673-677].


Asunto(s)
Salud Mental , Calidad de Vida , Trastornos Relacionados con Sustancias/terapia , Encuestas y Cuestionarios , Anciano , Australia , Consejo , Estudios Transversales , Depresión/diagnóstico , Femenino , Estado de Salud , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Centros de Tratamiento de Abuso de Sustancias , Trastornos Relacionados con Sustancias/psicología , Resultado del Tratamiento
20.
Int J Drug Policy ; 36: 104-11, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27453147

RESUMEN

BACKGROUND: Alprazolam, has been associated with disproportionate harms compared to other benzodiazepines, especially among people in opioid substitution treatment (OST). We examine the effect of the rescheduling of alprazolam in Australia, from Schedule 4 to Schedule 8 in February 2014 amongst a high-risk population of clients in OST. METHODS: OST participants who reported recent (last month) alprazolam use were recruited from three Sydney clinics. Participants (n=57) were interviewed immediately prior to rescheduling and again three months and 12 months after rescheduling. We examined self-reported patterns of drug use, drug availability, mental and physical health. A linear mixed models approach was used to analyse changes in alprazolam and other benzodiazepine use. RESULTS: Mean days of alprazolam use in the past 28 days decreased from 13.7 to 7.1 days, and mean weekly alprazolam dose decreased from 15.1mg to 6.1mg at 12 months follow-up (p=0.001). Total weekly benzodiazepine use also reduced from a mean of 222mg diazepam equivalent to 157mg (p=0.044). Other substance use did not change significantly. Reported mode of cost price of street alprazolam doubled from $5 to $10 over the 12-month period. CONCLUSION: Alprazolam rescheduling resulted in an overall reduction in alprazolam and total benzodiazepine use, without substitution with other drugs, in the short term. Unintended harms were not observed. Rescheduling appears to have been effective in reducing alprazolam use in this high-risk population.


Asunto(s)
Alprazolam/efectos adversos , Reducción del Daño , Hipnóticos y Sedantes/efectos adversos , Tratamiento de Sustitución de Opiáceos , Trastornos Relacionados con Opioides/rehabilitación , Mal Uso de Medicamentos de Venta con Receta/efectos adversos , Adulto , Alprazolam/administración & dosificación , Distribución de Chi-Cuadrado , Esquema de Medicación , Femenino , Humanos , Hipnóticos y Sedantes/administración & dosificación , Modelos Lineales , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Nueva Gales del Sur , Trastornos Relacionados con Opioides/diagnóstico , Trastornos Relacionados con Opioides/psicología , Mal Uso de Medicamentos de Venta con Receta/prevención & control , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
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