155 research outputs found
Embedded surfaces of arbitrary genus minimizing the Willmore energy under isoperimetric constraint
The isoperimetric ratio of an embedded surface in is defined as the
ratio of the area of the surface to power three to the squared enclosed volume.
The aim of the present work is to study the minimization of the Willmore energy
under fixed isoperimetric ratio when the underlying abstract surface has fixed
genus . The corresponding problem in the case of spherical surfaces,
i.e. , was recently solved by Schygulla with different methods.Comment: 38 page
Embedded Surfaces of Arbitrary Genus Minimizing the Willmore Energy Under Isoperimetric Constraint
The isoperimetric ratio of an embedded surface in R 3 is defined as the ratio of the area of the surface to power three to the squared enclosed volume. The aim of the present work is to study the minimization of the Willmore energy under fixed isoperimetric ratio when the underlying abstract surface has fixed genus g ≧ 0 . The corresponding problem in the case of spherical surfaces, that is g=0, was recently solved by Schygulla (see Schygulla, Arch Ration Mech Anal 203:901-941, 2012) with different methods
LITL at CLEF eHealth2016: recognizing entities in French biomedical documents
International audienceThis paper describes the participation of master's students (LITL programme, university of Toulouse) and their teachers to the CLEF eHealth 2016 campaign. Two runs were submitted for task 2 (multilingual information extraction) which consisted in the recognition and categorization of medical entities in French biomedical documents. The system used consists of a CRF classier based on a number of dierent features (POS tagging, generic word lists and syntactic parsing). In addition , several patterns were used on the CRF's output in order to extract more complex entities. The best run achieved high precision (0.640.78) but lower recall (0.320.40), with an overall F1-measure of 0.430.53
Early Diagnosis and Treatment of Purine Nucleoside Phosphorylase (PNP) Deficiency through TREC-Based Newborn Screening
Newborn screening; Severe combined immunodeficiencyCribatge nounat; Immunodeficiència combinada severaCribado neonato; Inmunodeficiencia combinada gravePurine nucleoside phosphorylase (PNP) deficiency is a rare inherited disorder, resulting in severe combined immunodeficiency. To date, PNP deficiency has been detected in newborn screening only through the use of liquid chromatography tandem mass spectrometry. We report the first case in which PNP deficiency was detected by TREC analysis.This research was funded by Jeffrey Modell Foundation
Common Variable Immunodeficiency and Neurodevelopmental Delay Due to a 13Mb Deletion on Chromosome 4 Including the NFKB1 Gene: A Case Report
Chromosomal rearrangements; Primary immunodeficiencies; Syndromic immunodeficienciesReordenacions cromosòmiques; Immunodeficiències primàries; Immunodeficiències sindròmiquesReordenamientos cromosómicos; Inmunodeficiencias primarias; Inmunodeficiencias sindrómicasSyndromic immunodeficiencies are a heterogeneous group of inborn errors of immunity that can affect the development of non-immune organs and systems. The genetic basis of these immunodeficiencies is highly diverse, ranging from monogenic defects to large chromosomal aberrations. Antibody deficiency is the most prevalent immunological abnormality in patients with syndromic immunodeficiencies caused by chromosomal rearrangements, and usually manifests as a common variable immunodeficiency (CVID)-like phenotype. Here we describe a patient with a complex phenotype, including neurodevelopmental delay, dysmorphic features, malformations, and CVID (hypogammaglobulinemia, reduced pre-switch and switch memory B cells, and impaired vaccine response). Microarray-based comparative genomic hybridization (aCGH) revealed a 13-Mb deletion on chromosome 4q22.2-q24 involving 53 genes, some of which were related to the developmental manifestations in our patient. Although initially none of the affected genes could be linked to his CVID phenotype, subsequent reanalysis identified NFKB1 haploinsufficiency as the cause. This study underscores the value of periodic reanalysis of unsolved genetic studies performed with high-throughput technologies (eg, next-generation sequencing and aCGH). This is important because of the ongoing incorporation of new data establishing the relationship between genes and diseases. In the present case, NFKB1 had not been associated with human disease at the time aCGH was performed. Eight years later, reanalysis of the genes included in the chromosome 4 deletion enabled us to identify NFKB1 haploinsufficiency as the genetic cause of our patient’s CVID. In the future, other genes included in the deletion may be linked to human disease, allowing us to better define the molecular basis of our patient’s complex clinical phenotype.This study was funded by Instituto de Salud Carlos III, grants PI17/00660 and PI20/00761, cofinanced by the European Regional Development Fund (ERDF). This study was also funded by the Jeffrey Modell Foundation. This work is supported by the European Reference Network for Rare Immunodeficiency, Autoinflammatory and Autoimmune Diseases Network (ERN-RITA)
Arabidopsiscell wall composition determines disease resistance specificity and fitness
[EN] Plant cell walls are complex structures subject to dynamic remodeling
in response to developmental and environmental cues and
play essential functions in disease resistance responses. We tested
the specific contribution of plant cell walls to immunity by
determining the susceptibility of a set of Arabidopsis cell wall mutants
(cwm) to pathogens with different parasitic styles: a vascular
bacterium, a necrotrophic fungus, and a biotrophic oomycete. Remarkably,
most cwm mutants tested (29/34; 85.3%) showed alterations
in their resistance responses to at least one of these
pathogens in comparison to wild-type plants, illustrating the relevance
of wall composition in determining disease-resistance phenotypes.
We found that the enhanced resistance of cwm plants to
the necrotrophic and vascular pathogens negatively impacted
cwm fitness traits, such as biomass and seed yield. Enhanced resistance
of cwm plants is not only mediated by canonical immune
pathways, like those modulated by phytohormones or microbeassociated
molecular patterns, which are not deregulated in the
cwm tested. Pectin-enriched wall fractions isolated from cwm
plants triggered immune responses in wild-type plants, suggesting
that wall-mediated defensive pathways might contribute to cwm
resistance. Cell walls of cwm plants show a high diversity of composition
alterations as revealed by glycome profiling that detect
specific wall carbohydrate moieties. Mathematical analysis of glycome
profiling data identified correlations between the amounts of
specific wall carbohydrate moieties and disease resistance phenotypes
of cwm plants. These data support the relevant and specific
function of plant wall composition in plant immune response modulation
and in balancing disease resistance/development trade-offs.SIThis work has been also financially supported by the Severo Ochoa Program for Centers of Excellence in R&D from the Agencia Estatal de Investigación of Spain (Grant SEV-2016-0672 (2017-2021) to the Centro de Biotecnología y Genómica de Plantas). In the frame of this program, H.M. was a postdoctoral fellow. H.M. was also supported by an Individual Fellowship grant (SignWALLINg-624721) from the European Union. E.M. was a Juan de la Cierva Postdoctoral Fellow from MINECO, and L.B. was a Formacion Personal Investigador fellow of MICIU. The generation of the CCRC-series of plant cell glycan-directed monoclonal antibodies used in this work was supported by the US NSF (DBI-0421683 and IOS 0923992) to M.G.H
Activation-induced deaminase is critical for the establishment of DNA methylation patterns prior to the germinal center reaction
Limfòcits b; Metilació de l'ADN; GenomaLinfocitos b; Metilación de ADN; GenomaB-lymphocytes; DNA methylation; GenomeActivation-induced deaminase (AID) initiates antibody diversification in germinal center B cells by deaminating cytosines, leading to somatic hypermutation and class-switch recombination. Loss-of-function mutations in AID lead to hyper-IgM syndrome type 2 (HIGM2), a rare human primary antibody deficiency. AID-mediated deamination has been proposed as leading to active demethylation of 5-methycytosines in the DNA, although evidence both supports and casts doubt on such a role. In this study, using whole-genome bisulfite sequencing of HIGM2 B cells, we investigated direct AID involvement in active DNA demethylation. HIGM2 naïve and memory B cells both display widespread DNA methylation alterations, of which ∼25% are attributable to active DNA demethylation. For genes that undergo active demethylation that is impaired in HIGM2 individuals, our analysis indicates that AID is not directly involved. We demonstrate that the widespread alterations in the DNA methylation and expression profiles of HIGM2 naïve B cells result from premature overstimulation of the B-cell receptor prior to the germinal center reaction. Our data support a role for AID in B cell central tolerance in preventing the expansion of autoreactive cell clones, affecting the correct establishment of DNA methylation patterns.Spanish Ministry of Science, Innovation and Universities [SAF2017-88086-R to E.B.]; cofunded by FEDER funds/European Regional Development Fund (ERDF)—a way to build Europe. E.B is supported by Instituto de Salud Carlos III (ISCIII), Ref. AC18/00057, associated with i-PAD project (ERARE European Union program); P.L. and C.P. are supported by the German Cancer Aid project CO-CLL [70113869]; B.G. is funded by the Deutsche Forschungsgemeinschaft [GR1617/14-1/iPAD, SFB1160/2_B5, RESIST–EXC 2155–Project ID 390874280, CIBSS–EXC-2189–Project ID 390939984]; BMBF [GAIN 01GM1910A]. Funding for open access charge: Spanish Ministry of Science, Innovation and Universities [SAF2017-88086-R]
Estado del arte de la quinua en el mundo en 2013
Alimento de base de las poblaciones andinas desde hace milenios, la quinua se ha convertido hoy en un producto apreciado en el mercado internacional de alimentos dietéticos, orgánicos y equitativos. Este cambio lo iniciaron los mismos productores del Altiplano Sur de Bolivia hace aproximadamente unos 40 años. En medio de un desierto de altura, ellos lograron desarrollar una floreciente producción agrícola de exportación. Aunque cuentan con lucrativos nichos de mercado, los productores de quinua no son agricultores especializados, ni residen de forma permanente en la zona de producción. Estas son algunas de las paradojas que caracterizan la producción de quinua en el Altiplano Sur de Bolivia. Después de describir el origen, la diversidad y los rasgos biológicos del ecotipo Quinua Real en el cual se basa la producción de esta zona, se plantea la importancia de la quinua en los agrosistemas locales y, más allá, en los sistemas de actividades agrícolas y no agrícolas manejados por las familias del Altiplano Sur. Movilidad geográfica y pluriactividad forman parte del modo de vida ancestral de estas poblaciones y determinan hasta hoy en día las condiciones de uso de los recursos territoriales y la organización de los productores en el contexto del auge comercial de la quinua. La producción actual de quinua en la región presenta rasgos de vulnerabilidad agroecológica y social, así como capacidades adaptativas para enfrentarlos. Se resaltan como puntos clave para la sostenibilidad de los agrosistemas locales : i) la concertación de reglas comunales e individuales para el acceso y uso de la tierra en agrosistemas socialmente equitativos y equilibrados entre cultivo y ganadería, ii) las normas internacionales para el reconocimiento de la Quinua Real en los mercados de exportación, iii) una actualización continua de las reglas y normas para mantener la adaptabilidad de los agrosistemas locales a los cambios imprevisibles del contexto socio-ecológico a varias escalas de espacio y de tiempo
Early Diagnosis and Treatment of Purine Nucleoside Phosphorylase (PNP) Deficiency through TREC-Based Newborn Screening
Purine nucleoside phosphorylase (PNP) deficiency is a rare inherited disorder, resulting in severe combined immunodeficiency. To date, PNP deficiency has been detected in newborn screening only through the use of liquid chromatography tandem mass spectrometry. We report the first case in which PNP deficiency was detected by TREC analysis
Activation-induced deaminase is critical for the establishment of DNA methylation patterns prior to the germinal center reaction
Activation-induced deaminase (AID) initiates antibody diversification in germinal center B cells by deaminating cytosines, leading to somatic hypermutation and class-switch recombination. Loss-of-function mutations in AID lead to hyper-IgM syndrome type 2 (HIGM2), a rare human primary antibody deficiency. AID-mediated deamination has been proposed as leading to active demethylation of 5-methycytosines in the DNA, although evidence both supports and casts doubt on such a role. In this study, using whole-genome bisulfite sequencing of HIGM2 B cells, we investigated direct AID involvement in active DNA demethylation. HIGM2 naïve and memory B cells both display widespread DNA methylation alterations, of which ∼25% are attributable to active DNA demethylation. For genes that undergo active demethylation that is impaired in HIGM2 individuals, our analysis indicates that AID is not directly involved. We demonstrate that the widespread alterations in the DNA methylation and expression profiles of HIGM2 naïve B cells result from premature overstimulation of the B-cell receptor prior to the germinal center reaction. Our data support a role for AID in B cell central tolerance in preventing the expansion of autoreactive cell clones, affecting the correct establishment of DNA methylation patterns
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