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1.
Neural Comput Appl ; 34(13): 10533-10545, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35153386

RESUMEN

Nowadays, electricity is a basic commodity necessary for the well-being of any modern society. Due to the growth in electricity consumption in recent years, mainly in large cities, electricity forecasting is key to the management of an efficient, sustainable and safe smart grid for the consumer. In this work, a deep neural network is proposed to address the electricity consumption forecasting in the short-term, namely, a long short-term memory (LSTM) network due to its ability to deal with sequential data such as time-series data. First, the optimal values for certain hyper-parameters have been obtained by a random search and a metaheuristic, called coronavirus optimization algorithm (CVOA), based on the propagation of the SARS-Cov-2 virus. Then, the optimal LSTM has been applied to predict the electricity demand with 4-h forecast horizon. Results using Spanish electricity data during nine years and half measured with 10-min frequency are presented and discussed. Finally, the performance of the proposed LSTM using random search and the LSTM using CVOA is compared, on the one hand, with that of recently published deep neural networks (such as a deep feed-forward neural network optimized with a grid search) and temporal fusion transformers optimized with a sampling algorithm, and, on the other hand, with traditional machine learning techniques, such as a linear regression, decision trees and tree-based ensemble techniques (gradient-boosted trees and random forest), achieving the smallest prediction error below 1.5%.

2.
Food Chem ; 374: 131742, 2022 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-34891088

RESUMEN

Yeasts can synthetise bioactive compounds such as Melatonin (MEL), Serotonin (SER) and Hydroxytyrosol (HT). Deciphering the mechanisms involved in their formation can lead to exploit this fact to increase the bioactive potential of fermented beverages. Quantitative analysis using labelled compounds, 15-N2 l-tryptophan and 13-C tyrosine, allowed tracking the formation of the above-mentioned bioactive compounds during the alcoholic fermentation of synthetic must by two different Saccharomyces cerevisiae strains. Labelled and unlabelled MEL, SER and HT were undoubtedly identified and quantified by High Resolution Mass Spectrometry (HRMS). Our results prove that there are at least two pathways involved in MEL biosynthesis by yeast. One starts with tryptophan as precursor being known for the vertebrates' pathway. Additionally, MEL is produced from SER which in turn is consistent with the plants' biosynthesis pathway. Concerning HT, it can be formed both from labelled tyrosine and from intermediates of the Erlich pathway.


Asunto(s)
Melatonina , Saccharomyces cerevisiae , Fermentación , Bebidas Fermentadas , Alcohol Feniletílico/análogos & derivados , Serotonina
3.
Rev. biol. trop ; 69(supl. 1)mar. 2021.
Artículo en Inglés | LILACS, SaludCR | ID: biblio-1507752

RESUMEN

Introduction: The echinoderms from the Central Mexican Pacific are of high scientific interest and, prior to this present work, there was a lack of basic information that included incomplete checklists with inconsistencies in systematics and spatial distribution. Objective: To provide a historical review, and an updated checklist with a more complete richness of echinoderms for each state and island of the region. Methods: A checklist was elaborated based on an exhaustive literature search of the Echinodermata, and was complemented with taxonomical revisions of Ophiuroidea scientific collections. All the geographical coordinates of the records were validated. Results: The region harbors 187 species of Echinodermata: three Crinoidea, 35 Asteroidea, 67 Ophiuroidea, 32 Echinoidea, and 50 Holothuroidea. We detected 52 records in the literature that must be considered as invalid and five as doubtful. We provide 16 new records of Ophiuroidea from different states and islands; of them, four are new records for the region. Jalisco presented the highest number of species (84), followed by the coast of Nayarit (74), Michoacán (63), and Colima (55); among the islands, Revillagigedo showed the major number of species (85) followed by Marías (81), Marietas (48), and Isabel (44). Conclusions: The numbers of species known in the region are mostly related to both sampling effort and environmental characteristics that promote high biodiversity. The Central Mexican Pacific is an oceanographic region with mixed conditions from the North and South of the Mexican Pacific, and therefore, with a biogeographical importance reflected in its species richness.


Introducción: Los equinodermos del Pacífico Central mexicano poseen un alto interés científico, pero anterior al presente trabajo existía un vacío en la información básica como listados de especies incompletos con inconsistencias sistemáticas y de distribución espacial. Objetivo: Proporcionar una revisión histórica y un listado de especies actualizado con la riqueza completa de equinodermos para cada estado e islas de la región. Métodos: Se elaboró un listado de especies basado en una búsqueda exhaustiva de Echinodermata, y fue complementada con la revisión taxonómica de Ophiuroidea de colecciones científicas. Todas las coordenadas geográficas de los registros fueron validadas. Resultados: La región posee 187 especies de Echinodermata: tres Crinoidea, 35 Asteroidea, 67 Ophiuroidea, 32 Echinoidea, y 50 Holothuroidea. Detectamos 52 registros en la literatura considerados como inválidos y cinco como dudosos. Proveemos 16 nuevos registros de Ophiuroidea para diversos estados e islas; de estos, cuatro son nuevos registros para la región. Jalisco presentó el mayor número de especies (84), seguido por las costas de Nayarit (74), Michoacán (63), y Colima (55); entre las islas, Revillagigedo presentó el mayor número de especies (85) seguido por Marías (81), Marietas (48), e Isabel (44). Conclusiones: Los números de especies de la región están mayormente relacionados tanto con el esfuerzo de muestreo como con características ambientales que promueven una alta biodiversidad. El Pacífico Central mexicano es una región oceanográfica con condiciones mixtas del norte y sur del Pacífico mexicano, y por lo tanto con una importancia biogeográfica reflejada en la riqueza de la región.


Asunto(s)
Animales , Equinodermos/anatomía & histología , Equinodermos/clasificación , Biodiversidad , México
4.
Big Data ; 8(4): 308-322, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32716641

RESUMEN

This study proposes a novel bioinspired metaheuristic simulating how the coronavirus spreads and infects healthy people. From a primary infected individual (patient zero), the coronavirus rapidly infects new victims, creating large populations of infected people who will either die or spread infection. Relevant terms such as reinfection probability, super-spreading rate, social distancing measures, or traveling rate are introduced into the model to simulate the coronavirus activity as accurately as possible. The infected population initially grows exponentially over time, but taking into consideration social isolation measures, the mortality rate, and number of recoveries, the infected population gradually decreases. The coronavirus optimization algorithm has two major advantages when compared with other similar strategies. First, the input parameters are already set according to the disease statistics, preventing researchers from initializing them with arbitrary values. Second, the approach has the ability to end after several iterations, without setting this value either. Furthermore, a parallel multivirus version is proposed, where several coronavirus strains evolve over time and explore wider search space areas in less iterations. Finally, the metaheuristic has been combined with deep learning models, to find optimal hyperparameters during the training phase. As application case, the problem of electricity load time series forecasting has been addressed, showing quite remarkable performance.


Asunto(s)
Algoritmos , Betacoronavirus/aislamiento & purificación , Infecciones por Coronavirus/transmisión , Heurística , Modelos Teóricos , Neumonía Viral/transmisión , COVID-19 , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/virología , Brotes de Enfermedades , Humanos , Pandemias , Neumonía Viral/epidemiología , Neumonía Viral/virología , Probabilidad , Cuarentena , SARS-CoV-2
5.
Br J Surg ; 107(10): 1334-1343, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32452559

RESUMEN

BACKGROUND: In gallbladder cancer, stage T2 is subdivided by tumour location into lesions on the peritoneal side (T2a) or hepatic side (T2b). For tumours on the peritoneal side (T2a), it has been suggested that liver resection may be omitted without compromising the prognosis. However, data to validate this argument are lacking. This study aimed to investigate the prognostic value of tumour location in T2 gallbladder cancer, and to clarify the adequate extent of surgical resection. METHODS: Clinical data from patients who underwent surgery for gallbladder cancer were collected from 14 hospitals in Korea, Japan, Chile and the USA. Survival and risk factor analyses were conducted. RESULTS: Data from 937 patients were available for evaluation. The overall 5-year disease-free survival rate was 70·6 per cent, 74·5 per cent for those with T2a and 65·5 per cent among those with T2b tumours (P = 0·028). Regarding liver resection, extended cholecystectomy was associated with a better 5-year disease-free survival rate than simple cholecystectomy (73·0 versus 61·5 per cent; P = 0·012). The 5-year disease-free survival rate was marginally better for extended than simple cholecystectomy in both T2a (76·5 versus 66·1 per cent; P = 0·094) and T2b (68·2 versus 56·2 per cent; P = 0·084) disease. Five-year disease-free survival rates were similar for extended cholecystectomies including liver wedge resection versus segment IVb/V segmentectomy (74·1 versus 71·5 per cent; P = 0·720). In multivariable analysis, independent risk factors for recurrence were presence of symptoms (hazard ratio (HR) 1·52; P = 0·002), R1 resection (HR 1·96; P = 0·004) and N1/N2 status (N1: HR 3·40, P < 0·001; N2: HR 9·56, P < 0·001). Among recurrences, 70·8 per cent were metastatic. CONCLUSION: Tumour location was not an independent prognostic factor in T2 gallbladder cancer. Extended cholecystectomy was marginally superior to simple cholecystectomy. A radical operation should include liver resection and adequate node dissection.


ANTECEDENTES: En el cáncer de vesícula biliar, la ubicación del tumor subdivide el estadio T2 en tumores con invasión del lado peritoneal y del lado del hígado (T2a y T2b). Para los tumores que invaden el lado peritoneal (T2a) se sugiere que se puede obviar la resección hepática sin que ello comprometa el pronóstico. Sin embargo, este argumento no ha sido validado. El estudio tuvo como objetivo investigar el valor pronóstico de la localización del tumor en el cáncer de vesícula biliar T2 y establecer la extensión adecuada de la resección quirúrgica. MÉTODOS: Se recogieron los datos clínicos de pacientes que se sometieron a cirugía por cáncer de vesícula biliar en 14 hospitales de Corea, Japón, Chile y Estados Unidos. Se realizaron análisis de la supervivencia y de los factores de riesgo. RESULTADOS: Se dispuso de datos de 937 pacientes para ser evaluados. La tasa de supervivencia global libre de enfermedad a los 5 años fue del 70,6%, y las de T2a y T2b del 74,5% y 65,5% (P = 0,028). Con respecto a la resección hepática, la colecistectomía extendida presentó una tasa mejor de supervivencia libre de enfermedad a los 5 años que la colecistectomía simple (73,0% versus 61,5%, P = 0,012). La tasa de supervivencia libre de enfermedad a los 5 años fue marginalmente mejor para la colecistectomía extendida que para la colecistectomía simple tanto en T2a (76,5% versus 66,1%, P = 0,094) como en T2b (68,2% versus 56,2%, P = 0,084). Las tasas de supervivencia libre de enfermedad a los 5 años no fueron diferentes entre la resección hepática en cuña y la segmentectomía S4b+S5 (74,1% versus 71,5%, P = 0,720). En el análisis multivariable, los factores de riesgo independientes para la recidiva fueron la presencia de síntomas (cociente de riesgos instantáneos, hazard ratio, HR 1,52, P = 0,002), la resección R1 (HR 1,96, P = 0,004) y el estadio N1/N2 (N1 HR 3,40, P < 0,001; N2 HR 9,56, P < 0,001). El 70,8% de las recidivas eran metastásicas. CONCLUSIÓN: La localización del tumor no fue un factor pronóstico independiente en el cáncer de vesícula biliar T2. La colecistectomía extendida fue marginalmente superior que la colecistectomía simple. La cirugía radical debe incluir una resección hepática y una linfadenectomía adecuada.


Asunto(s)
Neoplasias de la Vesícula Biliar/mortalidad , Neoplasias de la Vesícula Biliar/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Chile , Colecistectomía , Supervivencia sin Enfermedad , Femenino , Neoplasias de la Vesícula Biliar/patología , Hepatectomía , Humanos , Japón , Escisión del Ganglio Linfático , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia , Pronóstico , República de Corea , Factores de Riesgo , Estados Unidos
6.
J Chromatogr A ; 1522: 70-77, 2017 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-28969903

RESUMEN

Five free software packages were compared to assess their utility for the non-targeted study of changes in the volatile profile during the storage of a novel strawberry beverage. AMDIS coupled to Gavin software turned out to be easy to use, required the minimum handling for subsequent data treatment and its results were the most similar to those obtained by manual integration. However, AMDIS coupled to SpectConnect software provided more information for the study of volatile profile changes during the storage of strawberry beverage. During storage, volatile profile changed producing the differentiation among the strawberry beverage stored at different temperatures, and this difference increases as time passes; these results were also supported by PCA. As expected, it seems that cold temperature is the best way of preservation for this product during long time storage. Variable Importance in the Projection (VIP) and correlation scores pointed out four volatile compounds as potential markers for shelf-life of our strawberry beverage: 2-phenylethyl acetate, decanoic acid, γ-decalactone and furfural.


Asunto(s)
Bebidas/análisis , Análisis de los Alimentos/métodos , Almacenamiento de Alimentos , Fragaria , Programas Informáticos , Estadística como Asunto/métodos , Compuestos Orgánicos Volátiles/química , Acetatos/análisis , Frío , Lactonas/análisis , Alcohol Feniletílico/análogos & derivados , Alcohol Feniletílico/análisis
7.
Mar Environ Res ; 132: 23-32, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29054344

RESUMEN

Historical coral growth assessed by sclerochronology records provides an environmental retrospective and future perspective on the maintenance of coral-reef ecosystems. Three growth parameters, extension rate, skeletal density, and calcification rate were evaluated over the past two decade's interval (1988-2013) in different gender of two massive corals Pavona gigantea and Porites panamensis. The species P. gigantea calcified two-times faster (0.84 ± 0.29 g cm-2 yr-1) than P. panamensis (0.36 ± 0.15 g cm-2 yr-1); and male colonies presents13-58% higher calcification rates than females. Annual growth parameters do not show significant trends over the period 1988-2013, but significant, growth disruption associated with ENSO events. The data presented here suggest that P.gigantea and P.panamensis from the area have developed phenotypic plasticity to a wide range of environmental condition; the life history of both species is reflected in their calcification rates during both optimal and non-optimal conditions over the last two decades. Massive species develop denser structures that provide a permanent habitat to many marine species and contributes to the long-term maintenance of coral reef communities in the eastern tropical Pacific.


Asunto(s)
Antozoos/crecimiento & desarrollo , Arrecifes de Coral , Monitoreo del Ambiente , Animales
8.
Food Chem ; 217: 431-437, 2017 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-27664655

RESUMEN

Melatonin is a neurohormone involved in the regulation of circadian rhythms in humans. Evidence has recently been found of its occurrence in wines and its role in the winemaking process. The yeast Saccharomyces cerevisiae is consequently thought to be important in Melatonin synthesis, but limited data and reference texts are available on this synthetic pathway. This paper aims to elucidate whether the synthetic pathway of Melatonin in Saccharomyces and non-Saccharomyces strains involves these intermediates. To this end, seven commercial strains comprising Saccharomyces cerevisiae (Red Fruit, ES488, Lalvin QA23, Uvaferm BC, and Lalvin ICV GRE) and non-Saccharomyces (Torulaspora delbrueckii and Metschnikowia pulcherrima) were monitored, under controlled fermentation conditions, in synthetic must, for seven days. Samples were analysed using a UHPLC-HRMS system (Qexactive). Five out of the seven strains formed Melatonin during the fermentation process: three S. cerevisiae strains and the two non-Saccharomyces. Additionally, other compounds derived from l-tryptophan occurred during fermentation.


Asunto(s)
Fermentación/fisiología , Melatonina/metabolismo , Saccharomyces cerevisiae/metabolismo , Triptófano/metabolismo , Vino , Aromatizantes/aislamiento & purificación , Aromatizantes/metabolismo , Melatonina/aislamiento & purificación , Saccharomyces/metabolismo , Triptófano/aislamiento & purificación , Vino/análisis
9.
Food Chem ; 207: 261-71, 2016 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-27080904

RESUMEN

The volatile compositions of Charmat and traditional Chilean sparkling wines were studied for the first time. For this purpose, EG-Silicone and PDMS polymeric phases were compared and, afterwards, the most adequate was selected. The best extraction method turned out to be a sequential extraction in the headspace and by immersion using two PDMS twisters. A total of 130 compounds were determined. In traditional Chilean sparkling wines, ethyl esters were significantly higher, while acetic esters and ketones were predominant in the Charmat wines. PCA and LDA confirmed the differences in the volatile profiles between the production methods (traditional vs. Charmat).


Asunto(s)
Compuestos Orgánicos Volátiles/análisis , Vino/análisis , Chile , Ésteres/análisis , Industria de Alimentos , Cetonas/análisis
10.
J Chromatogr A ; 1428: 72-85, 2016 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-26372442

RESUMEN

One of the most common taints in foods is a musty or earthy odour, which is commonly associated with the activity of microorganisms. Liquid foods, particularly wine and water, can be affected by this defect due to the presence of certain aromatic organic compounds at very low concentrations (ng/L) consistent with human threshold perception levels. The volatile compounds responsible for a mouldy off-aroma include approximately 20 compounds, namely, haloanisoles, geosmin, 2-methylisoborneol, several alkyl-methoxypyrazines, 1-octen-3-ol, 1-octen-3-one, trans-octenol, 3-octanone, fenchol and fenchone. Methods for determining these very low concentrations of odour compounds must be extremely sensitive and selective with efficient preconcentration treatments. A number of extraction techniques based on LLME (liquid-liquid microextraction), SPME (solid-phase microextraction) or SBSE (stir-bar sorptive extraction) can be applied and should be selected on a case-by-case basis. Moreover, recent developments in GC instrumentation coupled to different detection systems can effectively increase the selectivity and sensitivity of the analysis of target compounds.


Asunto(s)
Tecnología de Alimentos/tendencias , Odorantes/análisis , Agua/química , Vino/análisis , Cromatografía de Gases y Espectrometría de Masas , Humanos , Cetonas/análisis , Compuestos Orgánicos Volátiles/análisis
11.
Food Chem ; 178: 221-8, 2015 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-25704705

RESUMEN

This paper studies the amino acid profile of beverages obtained through the fermentation of strawberry purée by a surface culture using three strains belonging to different acetic acid bacteria species (one of Gluconobacter japonicus, one of Gluconobacter oxydans and one of Acetobacter malorum). An HPLC-UV method involving diethyl ethoxymethylenemalonate (DEEMM) was adapted and validated. From the entire set of 21 amino acids, multiple linear regressions showed that glutamine, alanine, arginine, tryptophan, GABA and proline were significantly related to the fermentation process. Furthermore, linear discriminant analysis classified 100% of the samples correctly in accordance with the microorganism involved. G. japonicus consumed glucose most quickly and achieved the greatest decrease in amino acid concentration. None of the 8 biogenic amines were detected in the final products, which could serve as a safety guarantee for these strawberry gluconic fermentation beverages, in this regard.


Asunto(s)
Acetobacter/metabolismo , Aminoácidos/análisis , Aminas Biogénicas/análisis , Fermentación , Fragaria/química , Ácido Acético/metabolismo , Fragaria/metabolismo
12.
Talanta ; 89: 178-82, 2012 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-22284477

RESUMEN

A solid phase extraction method (SPE) using Isolute ENV+ cartridges was validated for the determination of ethyl carbamate (EC) in different kinds of vinegars. The method proved to be quite sensitive, precise and accurate, improving the recovery and LQD of other existing methods for the same purpose. For the optimization of the method, different pH values of the sample were tested, resulting 5.5 the most adequate. Among the 14 samples analysed, only 5 of them had contents of EC above the quantification limits, ranging between 6.73 µg/L and 56.4 µg/L. The highest value was found in red wine vinegar. Taking into account the amount of vinegar consumed in a meal and the limits established for alcoholic beverages in some countries, the levels of ethyl carbamate in the vinegars tested in this work were acceptable.


Asunto(s)
Ácido Acético/química , Carcinógenos/análisis , Uretano/análisis , Cromatografía de Gases y Espectrometría de Masas , Concentración de Iones de Hidrógeno , Límite de Detección , Reproducibilidad de los Resultados , Extracción en Fase Sólida/métodos
13.
Actas dermo-sifiliogr. (Ed. impr.) ; 102(4): 289-292, mayo 2011. ilus
Artículo en Español | IBECS | ID: ibc-88860

RESUMEN

El hamartoma angiomatoso ecrino es un tumor benigno e infrecuente que se caracteriza por la proliferación de elementos ecrinos y vasculares. Presentamos dos casos, el de una mujer de 33 años que consultó por una lesión marronácea en la espalda, con hiperhidrosis asociada, y el de un varón de 25 años con una lesión eritematosa, asintomática, en la palma izquierda. Tras el estudio histológico ambos pacientes se diagnosticaron de hamartoma angiomatoso ecrino. El hamartoma angiomatoso ecrino generalmente se presenta al nacimiento o en la infancia. Se manifiesta habitualmente como una lesión única con presentación clínica variable, por lo que su diagnóstico es fundamentalmente histológico. La localización más frecuente es la región distal de las extremidades. Suele ser asintomático, pero puede haber dolor e hiperhidrosis asociados. No requiere tratamiento salvo en aquellos casos asociados a sintomatología recalcitrante, sudor excesivo o por motivos estéticos (AU)


Eccrine angiomatous hamartoma is a rare, benign tumor characterized by a proliferation of eccrine and vascular structures. We present 2 cases and review the characteristics of this disorder. The first patient was a 33-year-old woman who consulted for a brownish lesion on her back associated with local hyperhidrosis. The second patient was a 25-year-old man withan asymptomatic erythematous lesion on his left palm. In both patients a diagnosis of eccrine angiomatous hamartoma was made based on the histological findings. Eccrine angiomatous hamartoma is usually present at birth or develops during childhood. It is typically a solitary lesion and signs and symptoms can vary; diagnosis is therefore based on histological study. The most common site is on the distal parts of limbs. The lesions tend to be asymptomatic, but there may be associated pain and hyperhidrosis. Treatment is not usually necessary except in cases with persistent symptoms, excessive sweating, or cosmetic concern (AU)


Asunto(s)
Humanos , Animales , Masculino , Femenino , Adulto , Hamartoma/diagnóstico , Hamartoma/patología , Hemangioma/diagnóstico , Hemangioma/patología , Acrospiroma/diagnóstico , Acrospiroma/patología , Hamartoma/etiología , Hamartoma/psicología , Hemangioma/psicología , Hemangioma/cirugía , Hiperhidrosis/complicaciones , Hiperhidrosis/patología , Histología/educación , Histología/estadística & datos numéricos , Histología/tendencias
14.
Actas Dermosifiliogr ; 102(4): 289-92, 2011 May.
Artículo en Español | MEDLINE | ID: mdl-21453905

RESUMEN

Eccrine angiomatous hamartoma is a rare, benign tumor characterized by a proliferation of eccrine and vascular structures. We present 2 cases and review the characteristics of this disorder. The first patient was a 33-year-old woman who consulted for a brownish lesion on her back associated with local hyperhidrosis. The second patient was a 25-year-old man with an asymptomatic erythematous lesion on his left palm. In both patients a diagnosis of eccrine angiomatous hamartoma was made based on the histological findings. Eccrine angiomatous hamartoma is usually present at birth or develops during childhood. It is typically a solitary lesion and signs and symptoms can vary; diagnosis is therefore based on histological study. The most common site is on the distal parts of limbs. The lesions tend to be asymptomatic, but there may be associated pain and hyperhidrosis. Treatment is not usually necessary except in cases with persistent symptoms, excessive sweating, or cosmetic concerns.


Asunto(s)
Glándulas Ecrinas/patología , Hemangioma/patología , Neoplasias de las Glándulas Sudoríparas/patología , Adulto , Hidróxido de Aluminio/uso terapéutico , Antitranspirantes/uso terapéutico , Femenino , Mano , Hemangioma/complicaciones , Humanos , Hiperhidrosis/tratamiento farmacológico , Hiperhidrosis/etiología , Masculino , Hombro , Neoplasias de las Glándulas Sudoríparas/complicaciones
15.
Asian Pac J Trop Biomed ; 1(4): 334-6, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23569788

RESUMEN

A case of pulmonary coinfection by Strongyloides stercoralis and Pneumocystis jiroveci has been detected in an AIDS patient treated in the Respiratory Intensive Care Unit of the Muñiz Hospital. At diagnosis, the patient presented cough with mucopurulent expectoration, dyspnea, fever, bilateral pulmonary infiltrates on the chest X-ray, negative bacilloscopy for acid fast bacteria and a CD4(+) T lymphocytes count of 52 cells/µL. The microbiological diagnosis was achieved by microscopic observation of the respiratory secretions obtained by bronchoalveolar lavage, while the wet mount examination revealed rhabditiform and filariform larvae of the nematode and foamy exudates, pathognomonic of the pulmonary pneumocystosis. It was the unique case of this association among about 3 000 samples performed in our laboratory in the last 10 years and diagnosed by microscopy. Other complementary stains (a rapid modification of Grocott, Kinyoun and Giemsa) were applied to the smears after the diagnosis of mycotic and parasitary infections achieved by fresh microscopy. Both physicians and microbiologists should take into account the possible coexistence of respiratory pathogens in immunocompromised patients, such as those with AIDS.


Asunto(s)
Coinfección/diagnóstico , Pneumocystis carinii/aislamiento & purificación , Neumonía por Pneumocystis/complicaciones , Neumonía por Pneumocystis/diagnóstico , Strongyloides stercoralis/aislamiento & purificación , Estrongiloidiasis/complicaciones , Estrongiloidiasis/diagnóstico , Infecciones Oportunistas Relacionadas con el SIDA/diagnóstico , Infecciones Oportunistas Relacionadas con el SIDA/patología , Adulto , Animales , Argentina , Líquido del Lavado Bronquioalveolar/microbiología , Líquido del Lavado Bronquioalveolar/parasitología , Técnicas de Laboratorio Clínico , Coinfección/patología , Humanos , Masculino , Microscopía , Neumonía por Pneumocystis/patología , Estrongiloidiasis/patología
16.
Talanta ; 81(4-5): 1143-52, 2010 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-20441877

RESUMEN

The amino acids present in foods and beverages affect the quality of these products and they play an important role in enology. Amino acids are consumed by yeasts as a source of nitrogen during alcoholic fermentation and are precursors of aroma compounds. In this review various chromatographic methodologies for the determination of amino acids are described, and specific applications for the analysis of amino acid content are discussed. Amino acids usually need to be derivatized to make them more detectable. Several derivatizing reagents have been employed for the determination of amino acids in enological applications, and each has its advantages and disadvantages.


Asunto(s)
Aminoácidos/análisis , Análisis de los Alimentos/métodos , Vitis/metabolismo , Vino/análisis , Ácido Acético/análisis , Alcoholes/química , Bebidas , Cromatografía de Gases/métodos , Cromatografía Líquida de Alta Presión , Electroforesis Capilar , Fermentación , Espectroscopía de Resonancia Magnética/métodos
17.
Anal Chim Acta ; 660(1-2): 68-75, 2010 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-20103145

RESUMEN

Organic wines were produced at pilot scale to select the best autochthonous and commercial yeast strains to obtain wines with high organoleptic qualities. We tested the behaviour of five S. cerevisiae yeast strains and determined their volatile composition and organoleptic characteristics by sensory analysis. A total of 51 volatile compounds were quantified in the wines produced. The concentration of most of the volatile compounds was significantly influenced depending on which yeast strain was inoculated. The differences observed in the volatile composition of the wines appear to be quantitative rather than qualitative. In general, acetals were the most abundant group of volatile compounds in all the samples studied, followed by alcohols without ethanol. The highest contents of volatile compounds were found in two of the wines produced by autochthonous yeast strains. The results obtained in the sensory analysis suggest that autochthonous yeast produced wines of higher organoleptic quality because this sample gave the highest value for the general impression attribute.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas/métodos , Saccharomyces cerevisiae/metabolismo , Umbral Sensorial/fisiología , Compuestos Orgánicos Volátiles/análisis , Vino/análisis , Femenino , Fermentación , Humanos , Masculino , Saccharomyces cerevisiae/crecimiento & desarrollo , Compuestos Orgánicos Volátiles/química , Vino/microbiología
18.
Rev. chil. neuro-psiquiatr ; 47(3): 209-214, 2009. ilus, tab
Artículo en Español | LILACS | ID: lil-556249

RESUMEN

Background: In pediatric optic neuritis usually occurs after an infectious event, with papilledema, bilateral and with good prognosis, with a low incidence of conversion to multiple sclerosis. The aim of this paper is to present the clinical and laboratory characteristics of cases of optic neuritis in children. Patients and Methods: 10 clinical cases of optic neuritis in children and youth aged 5 to 17 years, referred between 1995 to 2007. Results: The median age at presentation was 11 years. 8 cases were females. Four cases with a history of respiratory infection, bilateral involvement in 8 of 10 patients and 5 cases of retrobulbar optic neuritis. Magnetic resonance imaging showed T2 hyperintensity in the optic nerves affected in 5 patients. The study of cerebrospinal fluid was normal and oligoclonal bands in all cases. The cases treated with intravenous methylprednisolone had good recovery. Two cases have multiple sclerosis. Discussion: In this series of female patients predominated and limited history of previous infection. Cases with multiple sclerosis showed no clinical differences, but more hyperintense lesions on magnetic resonance. The cases treated with methylprednisolone had good visual prognosis.


Antecedentes: En pediatría la neuritis óptica generalmente se presenta después de un cuadro infeccioso, con edema de papila, que suele ser bilateral y tiene buen pronóstico. La conversión a esclerosis múltiple es baja. Nuestro objetivo es presentar las características clínicas y de laboratorio de casos de neuritis óptica en pediatría. Pacientes y Método: Se analizan 10 casos clínicos de neuritis óptica en niños y jóvenes entre 5 y 17 años, referidos entre los años 1995 a 2008. Resultados: La edad media de la serie fue de 11 años. 8 casos eran de sexo femenino; cuatro tenían antecedentes de infección respiratoria. En 8 de 10 pacientes el compromiso fue bilateral y 5 casos evolucionaron con neuritis óptica retrobulbar. La resonancia magnética mostró hiperintensidad en T2 en los nervios ópticos afectados en 5 pacientes. El estudio de líquido cefalorraquídeo y bandas oligoclonales fue normal en todos los casos. Los pacientes tratados con metilprednisolona endovenosa tuvieron buena recuperación. Sólo dos casos evolucionaron a esclerosis múltiple. Discusión: En esta serie predonimaron los pacientes de sexo femenino y el antecedente infeccioso fue poco frecuente. Los casos que evolucionaron a esclerosis múltiple no mostraron diferencias clínicas; sólo presentaron mayor cantidad de lesiones hiperintensas en la RM. Tuvieron mejor pronóstico visual los enfermos tratados con metilprednisolona.


Asunto(s)
Humanos , Masculino , Adolescente , Femenino , Niño , Neuritis Óptica/diagnóstico , Neuritis Óptica/fisiopatología , Esclerosis Múltiple/etiología , Estudios de Seguimiento , Neuritis Óptica/complicaciones , Pronóstico
19.
J Chromatogr A ; 1204(1): 93-103, 2008 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-18692195

RESUMEN

Quantification of aroma compounds in wine vinegars is challenging due to the complexity of the matrix and the low concentrations expected. A method for the determination of volatile compounds in wine vinegars employing headspace sorptive extraction-thermal desorption-gas chromatography-mass spectrometry (HSSE-TD-GC-MS) was developed. A central composite design was used to optimize the sampling condition. The proposed method was successfully validated and low detection and quantification limits was obtained. The application of the proposed methodology allows the determination of 53 compounds in different wine vinegars (red, Sherry). Five of them have been detected in wine vinegars for the first time.


Asunto(s)
Ácido Acético/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Sensibilidad y Especificidad , Volatilización
20.
Crit Rev Food Sci Nutr ; 48(7): 649-71, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18663616

RESUMEN

Over last decade an increasing interest for antioxidants in foods has arisen. The healthy properties of antioxidants related to the prevention of degenerative diseases are the main cause of this boom. An antioxidant prevents the oxidation process, the initial step of development of degenerative diseases, cancer and many others. Literature encompasses analytical methodology development to assess antioxidant properties of foods and beverages. The screening of antioxidant activity of foodstuffs is the subject of a large number of articles. Special interest has been addressed to wine, tea and chocolate. However, the crucial key in the prevention of disease is the action these antioxidants exert after their consumption. Studies involving human subjects are scarce due to the requirements of availability of volunteers and conditions to test are limited. This review summarizes data related to in vitro antioxidant activity of foods, emphasizing the main role of phenolic compounds. A critical comparison is realized between the biological significance of these values and the biological significance of in vivo measurements. In addition, the Plasma Antioxidant Capacity is evaluated and selected as biomarker for in vivo antioxidant status of human organism. In a second part, data collected from different intervention studies performed up to date are compiled and discussed. This review summarized data related to in vitro antioxidant activity of foods, emphasizing the main role of phenolic compounds. A critical comparison is realized between the biological significance of these values and the biological significance of in vivo measurements. In addition, the Plasma Antioxidant Capacity is evaluated and selected as biomarker for in vivo antioxidant status of human organism. In a second part, data collected from different intervention studies performed up to date are compiled and discussed. The original contribution of this work is to compile data of Plasma Antioxidant Capacity after dietetic intervention studies taking into account the portion of food ingested. In addition, we calculated the antioxidant compounds content (phenolic content, ascorbic acid, vitamin E and carotenoids) contained in each food ingested to evaluate better their impact in Plasma Antioxidant Capacity. Intervention studies are grouped by the length of intervention and type of food ingested. Results reported in literature reveal that the increment in Plasma Antioxidant Capacity largely depends on analytical method used.


Asunto(s)
Antioxidantes/metabolismo , Análisis de los Alimentos , Fenoles/metabolismo , Antioxidantes/química , Enfermedades Cardiovasculares/prevención & control , Dieta , Humanos , Fenoles/sangre , Fenoles/química , Especies Reactivas de Oxígeno
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