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1.
Proc Natl Acad Sci U S A ; 112(19): 5893-8, 2015 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-25897020

RESUMEN

Archaeochemistry as the application of the most recent analytical techniques to ancient samples now provides an unprecedented understanding of human culture throughout history. In this paper, we report on a multiplatform analytical investigation of 170-y-old champagne bottles found in a shipwreck at the bottom of the Baltic Sea, which provides insight into winemaking practices used at the time. Organic spectroscopy-based nontargeted metabolomics and metallomics give access to the detailed composition of these wines, revealing, for instance, unexpected chemical characteristics in terms of small ion, sugar, and acid contents as well as markers of barrel aging and Maillard reaction products. The distinct aroma composition of these ancient champagne samples, first revealed during tasting sessions, was later confirmed using state-of-the-art aroma analysis techniques. After 170 y of deep sea aging in close-to-perfect conditions, these sleeping champagne bottles awoke to tell us a chapter of the story of winemaking and to reveal their extraordinary archaeometabolome and elemental diversity in the form of chemical signatures related to each individual step of champagne production.


Asunto(s)
Gusto , Vino/análisis , Arqueología , Dióxido de Carbono/química , Cromatografía Liquida , Furaldehído/análogos & derivados , Furaldehído/química , Espectroscopía de Resonancia Magnética , Reacción de Maillard , Espectrometría de Masas , Metabolómica , Espectrofotometría
2.
Molecules ; 19(11): 18033-56, 2014 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-25379642

RESUMEN

Phytoalexins are low molecular weight antimicrobial compounds that are produced by plants as a response to biotic and abiotic stresses. As such they take part in an intricate defense system which enables plants to control invading microorganisms. In this review we present the key features of this diverse group of molecules, namely their chemical structures, biosynthesis, regulatory mechanisms, biological activities, metabolism and molecular engineering.


Asunto(s)
Antiinfecciosos/metabolismo , Inmunidad de la Planta/fisiología , Plantas/metabolismo , Plantas/microbiología , Sesquiterpenos/metabolismo , Estrés Fisiológico/fisiología , Humanos , Fitoalexinas
3.
Ophthalmic Epidemiol ; 18(4): 146-9, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21780872

RESUMEN

PURPOSE: To establish that trachoma is a public health problem in Burundi, and to provide baseline data on the prevalence of active trachoma and unclean faces prior to the commencement of trachoma elimination activities in endemic districts. METHODS: For each of 11 pilot districts, eight collines (hills) (estimated population generally 1000-8000) were selected at random using a population-proportional-to-size technique; from each selected colline, one sous-colline (of which there are generally 3-5 per colline) was selected at random by simple random draw. In each selected sous-colline, all available 1-9-year-old children were examined for clinical signs of trachoma, and for signs of an unclean face (defined as eye discharge, nose discharge and/or presence of one or more flies on the face during the time taken to examine the eyes). RESULTS: A mean of 230 children were examined per sous-colline (range 44-600); in all, 20,659 children were examined in 90 sous-collines of 11 districts. (In one district, 10 rather than eight sous-collines were selected.) In three contiguous districts (Buhiga, Nyabikere and Muyinga) in the country's north-east, the prevalence of the sign "trachomatous inflammation-follicular" (TF) in 1-9-year-olds was >10%. In nine districts, the prevalence of unclean faces was >10%. CONCLUSION: Trachoma is a public health problem in Burundi. Implementation of trachoma control activities is indicated in at least Buhiga, Nyabikere and Muyinga. Further work should be carried out to establish the likely backlog of unoperated trachomatous trichiasis.


Asunto(s)
Enfermedades Endémicas , Tracoma/epidemiología , Burundi/epidemiología , Niño , Preescolar , Femenino , Investigación sobre Servicios de Salud , Encuestas Epidemiológicas , Humanos , Lactante , Masculino , Prevalencia
4.
Trop Med Int Health ; 15(2): 198-207, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20409287

RESUMEN

OBJECTIVE: To determine spatial patterns of co-endemicity of schistosomiasis mansoni and the soil-transmitted helminths (STHs) Ascaris lumbricoides, Trichuris trichiura and hookworm in the Great Lakes region of East Africa, to help plan integrated neglected tropical disease programmes in this region. METHOD: Parasitological surveys were conducted in Uganda, Tanzania, Kenya and Burundi in 28 213 children in 404 schools. Bayesian geostatistical models were used to interpolate prevalence of these infections across the study area. Interpolated prevalence maps were overlaid to determine areas of co-endemicity. RESULTS: In the Great Lakes region, prevalence was 18.1% for Schistosoma mansoni, 50.0% for hookworm, 6.8% for A. lumbricoides and 6.8% for T. trichiura. Hookworm infection was ubiquitous, whereas S. mansoni, A. lumbricoides and T. trichiura were highly focal. Most areas were endemic (prevalence >or=10%) or hyperendemic (prevalence >or=50%) for one or more STHs, whereas endemic areas for schistosomiasis mansoni were restricted to foci adjacent large perennial water bodies. CONCLUSION: Because of the ubiquity of hookworm, treatment programmes are required for STH throughout the region but efficient schistosomiasis control should only be targeted at limited high-risk areas. Therefore, integration of schistosomiasis with STH control is only indicated in limited foci in East Africa.


Asunto(s)
Helmintiasis/epidemiología , África Oriental/epidemiología , Animales , Ascariasis/epidemiología , Ascariasis/prevención & control , Ascaris lumbricoides , Prestación Integrada de Atención de Salud/métodos , Enfermedades Endémicas , Métodos Epidemiológicos , Femenino , Sistemas de Información Geográfica , Helmintiasis/prevención & control , Infecciones por Uncinaria/epidemiología , Infecciones por Uncinaria/prevención & control , Humanos , Masculino , Esquistosomiasis mansoni/epidemiología , Esquistosomiasis mansoni/prevención & control , Tricuriasis/epidemiología , Tricuriasis/prevención & control
5.
PLoS Negl Trop Dis ; 3(9): e517, 2009 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-19753110

RESUMEN

BACKGROUND: Intestinal schistosomiasis and soil-transmitted helminth (STH) infections constitute major public health problems in many parts of sub-Saharan Africa. In this study we examined the functional significance of such polyparasite infections in anemia and undernutrition in Rwandan individuals. METHODS: Three polyparasite infection profiles were defined, in addition to a reference profile that consisted of either no infections or low-intensity infection with only one of the focal parasite species. Logistic regression models were applied to data of 1,605 individuals from 6 schools in 2 districts of the Northern Province before chemotherapeutic treatment in order to correctly identify individuals who were at higher odds of being anaemic and/or undernourished. FINDINGS: Stunted relative to nonstunted, and males compared to females, were found to be at higher odds of being anaemic independently of polyparasite infection profile. The odds of being wasted were 2-fold greater for children with concurrent infection of at least 2 parasites at M+ intensity compared to those children with the reference profile. Males compared to females and anaemic compared to nonanaemic children were significantly more likely to be stunted. None of the three polyparasite infection profiles were found to have significant effects on stunting. CONCLUSION: The present data suggest that the levels of polyparasitism, and infection intensities in the Rwandan individuals examined here may be lower as compared to other recent similar epidemiological studies in different regions across sub-Saharan Africa. Neither the odds of anaemia nor the odds of stunting were found to be significantly different in the three-polyparasite infection profiles. However, the odds of wasting were higher in those children with at least two parasites at M+ intensity compared to those children with the reference profile. Nevertheless, despite the low morbidity levels indicated in the population under study here, we recommend sustainable efforts for the deworming of affected populations to be continued in order to support the economic development of the country.

6.
Br J Haematol ; 144(4): 538-45, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19055664

RESUMEN

Alpha thalassaemia myelodysplastic syndrome (ATMDS) is an unusual complication of chronic myeloid malignancy that is associated with a striking red cell phenotype. It represents an acquired form of alpha-thalassaemia that most commonly arises in the context of myelodysplasia. It has recently been shown that this condition occurs in association with somatic mutations of a known X-encoded trans-acting regulator of alpha globin gene (HBA) expression, ATRX. There is an unexplained, strong male preponderance of individuals with the ATMDS phenotype with a >5:1 male-female ratio and furthermore, all the somatic ATRX mutations described to date have been in males. Here we report the identification, in a single centre, of two females with ATMDS and mutations in the ATRX gene, proving that ATMDS associated with such mutations may occur, albeit rarely, in females. It seemed possible that females might be less likely to develop ATMDS if the inactivated copy of the ATRX gene (ATRX) became progressively re-activated throughout life. This study ruled out this hypothesis by investigating the pattern of ATRX inactivation in a cross-sectional analysis of normal females at ages ranging from newborn to 90 years.


Asunto(s)
Síndromes Mielodisplásicos/genética , Inactivación del Cromosoma X , Talasemia alfa/genética , Anciano , Estudios Transversales , ADN Helicasas/genética , Metilación de ADN , Análisis Mutacional de ADN/métodos , Epigénesis Genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mutación , Síndromes Mielodisplásicos/patología , Proteínas Nucleares/genética , Distribución por Sexo , Proteína Nuclear Ligada al Cromosoma X , Talasemia alfa/patología
7.
J Biol Chem ; 279(21): 21793-801, 2004 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-14970235

RESUMEN

The human alpha-globin complex lies at the tip of the short arm of chromosome 16. It comprises three functional globin genes (5'-zeta2-alpha2-alpha1-3'), the expression of which is strictly dependent on a positive regulatory element located 40-kb upstream, HS-40. This DNase I-hypersensitive site is the only known regulatory element displaying strong erythroid-specific enhancer activity within the human alpha-globin complex. How this enhancer activity is shared among different erythroid genes present in the same cluster without affecting the ubiquitous genes present within and around the complex is poorly understood. To address this issue, we used hybrid murine erythroleukemia cells containing a single copy of human chromosome 16 and targeted the insertion of different sequences downstream of HS-40 by recombinase-mediated cassette exchange. We thus demonstrate that (i). HS-40-mediated erythroid-specific activation of the alpha-globin genes is impaired solely by the insertion of a promoter sequence and not a coding sequence, unless it is methylated, and that (ii). the degree of transcriptional repression observed seems to be related directly to the transcriptional rate of the inserted promoter. Taken together, these results emphasize the importance of promoter sequences as the main targets for the activation mechanism of the human alpha-globin genes by HS-40.


Asunto(s)
Globinas/química , Animales , Sitios de Unión , Línea Celular Tumoral , Cromosomas Humanos Par 16 , Clonación Molecular , Genes Reguladores , Globinas/metabolismo , Humanos , Ratones , Modelos Genéticos , Mutagénesis , Plásmidos/metabolismo , Regiones Promotoras Genéticas , Recombinasas/metabolismo , Ribonucleasas/metabolismo , Transcripción Genética
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