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1.
Phys Rev Lett ; 118(22): 222002, 2017 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-28621966

RESUMEN

We report the first longitudinal-transverse separation of the deeply virtual exclusive π^{0} electroproduction cross section off the neutron and coherent deuteron. The corresponding four structure functions dσ_{L}/dt, dσ_{T}/dt, dσ_{LT}/dt, and dσ_{TT}/dt are extracted as a function of the momentum transfer to the recoil system at Q^{2}=1.75 GeV^{2} and x_{B}=0.36. The ed→edπ^{0} cross sections are found compatible with the small values expected from theoretical models. The en→enπ^{0} cross sections show a dominance from the response to transversely polarized photons, and are in good agreement with calculations based on the transversity generalized parton distributions of the nucleon. By combining these results with previous measurements of π^{0} electroproduction off the proton, we present a flavor decomposition of the u and d quark contributions to the cross section.

2.
Heredity (Edinb) ; 118(3): 249-259, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27876803

RESUMEN

Plant architecture, phenology and yield components of cultivated plants have repeatedly been shaped by selection to meet human needs and adaptation to different environments. Here we assessed the genetic architecture of 24 correlated maize traits that interact during plant cycle. Overall, 336 lines were phenotyped in a network of 9 trials and genotyped with 50K single-nucleotide polymorphisms. Phenology was the main factor of differentiation between genetic groups. Then yield components distinguished dents from lower yielding genetic groups. However, most of trait variation occurred within group and we observed similar overall and within group correlations, suggesting a major effect of pleiotropy and/or linkage. We found 34 quantitative trait loci (QTLs) for individual traits and six for trait combinations corresponding to PCA coordinates. Among them, only five were pleiotropic. We found a cluster of QTLs in a 5 Mb region around Tb1 associated with tiller number, ear row number and the first PCA axis, the latter being positively correlated to flowering time and negatively correlated to yield. Kn1 and ZmNIP1 were candidate genes for tillering, ZCN8 for leaf number and Rubisco Activase 1 for kernel weight. Experimental repeatabilities, numbers of QTLs and proportion of explained variation were higher for traits related to plant development such as tillering, leaf number and flowering time, than for traits affected by growth such as yield components. This suggests a simpler genetic determinism with larger individual QTL effects for the first category.


Asunto(s)
Mapeo Cromosómico , Sitios de Carácter Cuantitativo , Zea mays/genética , Estudios de Asociación Genética , Ligamiento Genético , Genotipo , Repeticiones de Microsatélite , Modelos Genéticos , Fenotipo , Polimorfismo de Nucleótido Simple , Zea mays/fisiología
3.
Phys Rev Lett ; 117(26): 262001, 2016 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-28059549

RESUMEN

We present deeply virtual π^{0} electroproduction cross-section measurements at x_{B}=0.36 and three different Q^{2} values ranging from 1.5 to 2 GeV^{2}, obtained from Jefferson Lab Hall A experiment E07-007. The Rosenbluth technique is used to separate the longitudinal and transverse responses. Results demonstrate that the cross section is dominated by its transverse component and, thus, is far from the asymptotic limit predicted by perturbative quantum chromodynamics. Nonetheless, an indication of a nonzero longitudinal contribution is provided by the measured interference term σ_{LT}. Results are compared with several models based on the leading-twist approach of generalized parton distributions (GPDs). In particular, a fair agreement is obtained with models in which the scattering amplitude includes convolution terms of chiral-odd (transversity) GPDs of the nucleon with the twist-3 pion distribution amplitude. This experiment, together with previous extensive unseparated measurements, provides strong support to the exciting idea that transversity GPDs can be accessed via neutral pion electroproduction in the high-Q^{2} regime.

4.
Microb Ecol ; 72(3): 608-20, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27535039

RESUMEN

Microscopic eukaryotes play a key role in ecosystem functioning, but their diversity remains largely unexplored in most environments. To advance our knowledge of eukaryotic microorganisms and the factors that structure their communities, high-throughput sequencing was used to characterize their diversity and spatial distribution along the pollution gradient of the acid mine drainage at Carnoulès (France). A total of 16,510 reads were retrieved leading to the identification of 323 OTUs after normalization. Phylogenetic analysis revealed a quite diverse eukaryotic community characterized by a total of eight high-level lineages including 37 classes. The majority of sequences were clustered in four main groups: Fungi, Stramenopiles, Alveolata and Viridiplantae. The Reigous sediments formed a succession of distinct ecosystems hosting contrasted eukaryotic communities whose structure appeared to be at least partially correlated with sediment mineralogy. The concentration of arsenic in the sediment was shown to be a significant factor driving the eukaryotic community structure along this continuum.


Asunto(s)
Arsénico/análisis , Biodiversidad , Contaminación Ambiental/análisis , Eucariontes/clasificación , Eucariontes/genética , Eucariontes/aislamiento & purificación , Sedimentos Geológicos/química , Ensayos Analíticos de Alto Rendimiento , Alveolados/clasificación , Alveolados/genética , Alveolados/aislamiento & purificación , Secuencia de Bases , Clasificación , ADN , Ecología , Ecosistema , Francia , Hongos/clasificación , Hongos/genética , Hongos/aislamiento & purificación , Concentración de Iones de Hidrógeno , Minería , Filogenia , ARN Ribosómico 18S/genética , Ríos , Análisis de Secuencia , Estramenopilos/clasificación , Estramenopilos/genética , Estramenopilos/aislamiento & purificación , Viridiplantae/clasificación , Viridiplantae/genética , Contaminantes Químicos del Agua/análisis , Contaminación del Agua
5.
J Appl Microbiol ; 119(4): 1112-26, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26218193

RESUMEN

AIM: To isolate and characterize rhizobacteria from Theobroma cacao with antagonistic activity against Phytophthora palmivora, the causal agent of the black pod rot, which is one of the most important diseases of T. cacao. METHODS AND RESULTS: Among 127 rhizobacteria isolated from cacao rhizosphere, three isolates (CP07, CP24 and CP30) identified as Pseudomonas chlororaphis, showed in vitro antagonistic activity against P. palmivora. Direct antagonism tested in cacao detached leaves revealed that the isolated rhizobacteria were able to reduce symptom severity upon infection with P. palmivora Mab1, with Ps. chlororaphis CP07 standing out as a potential biocontrol agent. Besides, reduced symptom severity on leaves was also observed in planta where cacao root system was pretreated with the isolated rhizobacteria followed by leaf infection with P. palmivora Mab1. The production of lytic enzymes, siderophores, biosurfactants and HCN, as well as the detection of genes encoding antibiotics, the formation of biofilm, and bacterial motility were also assessed for all three rhizobacterial strains. By using a mutant impaired in viscosin production, derived from CP07, it was found that this particular biosurfactant turned out to be crucial for both motility and biofilm formation, but not for the in vitro antagonism against Phytophthora, although it may contribute to the bioprotection of T. cacao. CONCLUSIONS: In the rhizosphere of T. cacao, there are rhizobacteria, such as Ps. chlororaphis, able to protect plants against P. palmivora. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides a theoretical basis for the potential use of Ps. chlororaphis CP07 as a biocontrol agent for the protection of cacao plants from P. palmivora infection.


Asunto(s)
Antibiosis , Cacao/microbiología , Phytophthora/fisiología , Enfermedades de las Plantas/microbiología , Pseudomonas/fisiología , Rizosfera , Cacao/crecimiento & desarrollo , Datos de Secuencia Molecular , Enfermedades de las Plantas/prevención & control , Raíces de Plantas/microbiología , Pseudomonas/genética , Pseudomonas/aislamiento & purificación
6.
Microb Ecol ; 67(1): 129-44, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24189653

RESUMEN

The impact of both organic and inorganic pollution on the structure of soil microbial communities is poorly documented. A short-time batch experiment (6 days) was conducted to study the impact of both types of pollutants on the taxonomic, metabolic and functional diversity of soil bacteria. For this purpose sand spiked with phenanthrene (500 mg kg(-1) sand) or arsenic (arsenite 0.66 mM and arsenate 12.5 mM) was supplemented with artificial root exudates and was inoculated with bacteria originated from an aged PAH and heavy-metal-polluted soil. The bacterial community was characterised using bacterial strain isolation, TTGE fingerprinting and proteomics. Without pollutant, or with phenanthrene or arsenic, there were no significant differences in the abundance of bacteria and the communities were dominated by Pseudomonas and Paenibacillus genera. However, at the concentrations used, both phenanthrene or arsenic were toxic as shown by the decrease in mineralisation activities. Using community-level physiological profiles (Biolog Ecoplates™) or differential proteomics, we observed that the pollutants had an impact on the community physiology, in particular phenanthrene induced a general cellular stress response with changes in the central metabolism and membrane protein synthesis. Real-time PCR quantification of functional genes and transcripts revealed that arsenic induced the transcription of functional arsenic resistance and speciation genes (arsB, ACR3 and aioA), while no transcription of PAH-degradation genes (PAH-dioxygenase and catechol-dioxygenase) was detected with phenanthrene. Altogether, in our tested conditions, pollutants do not have a major effect on community abundance or taxonomic composition but rather have an impact on metabolic and functional bacterial properties.


Asunto(s)
Arsénico/química , Bacterias/aislamiento & purificación , Fenantrenos/química , Microbiología del Suelo , Contaminantes del Suelo/química , Bacterias/clasificación , Bacterias/metabolismo , Genes Bacterianos , Metaboloma , Exudados de Plantas/química , Proteoma , ARN Ribosómico 16S/genética , Dióxido de Silicio/química , Estrés Fisiológico
7.
Extremophiles ; 16(4): 645-57, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22714283

RESUMEN

The Carnoulès mine is an extreme environment located in the South of France. It is an unusual ecosystem due to its acidic pH (2-3), high concentration of heavy metals, iron, and sulfate, but mainly due to its very high concentration of arsenic (up to 10 g L⁻¹ in the tailing stock pore water, and 100-350 mg L⁻¹ in Reigous Creek, which collects the acid mine drainage). Here, we present a survey of the archaeal community in the sediment and its temporal variation using a culture-independent approach by cloning of 16S rRNA encoding genes. The taxonomic affiliation of Archaea showed a low degree of biodiversity with two different phyla: Euryarchaeota and Thaumarchaeota. The archaeal community varied in composition and richness throughout the sampling campaigns. Many sequences were phylogenetically related to the order Thermoplasmatales represented by aerobic or facultatively anaerobic, thermoacidophilic autotrophic or heterotrophic organisms like the organotrophic genus Thermogymnomonas. Some members of Thermoplasmatales can also derive energy from sulfur/iron oxidation or reduction. We also found microorganisms affiliated with methanogenic Archaea (Methanomassiliicoccus luminyensis), which are involved in the carbon cycle. Some sequences affiliated with ammonia oxidizers, involved in the first and rate-limiting step in nitrification, a key process in the nitrogen cycle were also observed, including Candidatus Nitrososphaera viennensis and Candidatus nitrosopumilus sp. These results suggest that Archaea may be important players in the Reigous sediments through their participation in the biochemical cycles of elements, including those of carbon and nitrogen.


Asunto(s)
Archaea , Arsénico/metabolismo , Biodiversidad , Agua Subterránea/microbiología , Microbiología del Agua , Archaea/clasificación , Archaea/genética , Archaea/aislamiento & purificación , Archaea/metabolismo , Arsénico/química , Francia , Concentración de Iones de Hidrógeno , Filogenia , ARN de Archaea , ARN Ribosómico 16S
8.
Microbiology (Reading) ; 156(Pt 8): 2336-2342, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20447996

RESUMEN

Herminiimonas arsenicoxydans is a Gram-negative bacterium able to detoxify arsenic-contaminated environments by oxidizing arsenite [As(III)] to arsenate [As(V)] and by scavenging arsenic ions in an extracellular matrix. Its motility and colonization behaviour have been previously suggested to be influenced by arsenite. Using time-course confocal laser scanning microscopy, we investigated its biofilm development in the absence and presence of arsenite. Arsenite was shown to delay biofilm initiation in the wild-type strain; this was partly explained by its toxicity, which caused an increased growth lag time. However, this delayed adhesion step in the presence of arsenite was not observed in either a swimming motility defective fliL mutant or an arsenite oxidase defective aoxB mutant; both strains displayed the wild-type surface properties and growth capacities. We propose that during the biofilm formation process arsenite acts on swimming motility as a result of the arsenite oxidase activity, preventing the switch between planktonic and sessile lifestyles. Our study therefore highlights the existence, under arsenite exposure, of a competition between swimming motility, resulting from arsenite oxidation, and biofilm initiation.


Asunto(s)
Arsenitos/farmacología , Biopelículas/efectos de los fármacos , Oxalobacteraceae/fisiología , Biopelículas/crecimiento & desarrollo , Microscopía Confocal , Oxalobacteraceae/efectos de los fármacos , Oxidación-Reducción , Oxidorreductasas/metabolismo
9.
Phys Rev Lett ; 103(20): 202501, 2009 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-20365979

RESUMEN

An experimental study of the (16)O(e,e'K(+))(Lambda)(16)N reaction has been performed at Jefferson Lab. A thin film of falling water was used as a target. This permitted a simultaneous measurement of the p(e,e'K(+))Lambda, Sigma(0) exclusive reactions and a precise calibration of the energy scale. A ground-state binding energy of 13.76+/-0.16 MeV was obtained for (Lambda)(16)N with better precision than previous measurements on the mirror hypernucleus (Lambda)(16)O. Precise energies have been determined for peaks arising from a Lambda in s and p orbits coupled to the p(1/2) and p(3/2) hole states of the (15)N core nucleus.

10.
Bone Marrow Transplant ; 53(8): 960-966, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29440738

RESUMEN

Autologous stem cell transplantation (auto-HSCT) is an effective treatment strategy for hematological malignancies. The standard mode of handling hematopoietic progenitors for the autologous procedure (CRYO) consists on its collection and freezing with dimethyl sulfoxide (DMSO) and its subsequent thawing and re-infusion. This process is toxic and expensive. Non-cryopreserved (non-CRYO) is a less expensive mode of auto-HSCT. We designed a comparative study between both strategies performed in two different centers to analyze the short-term complications. In total 111 auto-HSCT were performed from January/2015 to October/2016 (42 non-CRYO and 74 CRYO). There were 74 males and 69 (62%) patients had the underlying diagnosis of multiple myeloma. No differences were seen on the characteristics of the apheresis products and their viability. Engraftment was significantly faster in the non-CRYO group (p = 0.001). Febrile neutropenia and severe mucositis were lower in the non-CRYO group (40% vs 92% p = 0.0001 and 11% vs 64%, p = 0.001, respectively). In addition, length of hospitalization was 5 days shorter in the non-CRYO group (p = 0.0001). Overall responses and transplantation outcomes were similar. Our data demonstrate a clear advantage of the non-CRYO over CRYO auto-HSCT with faster engraftment, lower incidence of febrile neutropenia and shorter hospital stay after the transplantation procedure. These data are especially relevant for centers with high transplant activity or with limited resources.


Asunto(s)
Criopreservación/métodos , Trasplante de Células Madre Hematopoyéticas/métodos , Acondicionamiento Pretrasplante/métodos , Trasplante Autólogo/métodos , Femenino , Humanos , Masculino , Resultado del Tratamiento
11.
Phys Rev Lett ; 99(5): 052501, 2007 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-17930747

RESUMEN

An experiment measuring electroproduction of hypernuclei has been performed in hall A at Jefferson Lab on a 12C target. In order to increase counting rates and provide unambiguous kaon identification two superconducting septum magnets and a ring imaging Cherenkov detector were added to the hall A standard equipment. An unprecedented energy resolution of less than 700 keV FWHM has been achieved. Thus, the observed (Lambda)(12)B spectrum shows for the first time identifiable strength in the core-excited region between the ground-state s-wave Lambda peak and the 11 MeV p-wave Lambda peak.

12.
Diabetes Metab ; 43(1): 59-68, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27316980

RESUMEN

AIM: Recent guidelines for the management of type 2 diabetes (T2DM) in the elderly recommend adjusting the therapeutic target (HbA1c) according to the patient's health. Our study aimed to explore the association between achieving the recommended personalized HbA1c target and the occurrence of major clinical events under real-life conditions. METHODS: The T2DM S.AGES cohort was a prospective multicentre study into which 213 general practitioners recruited 983 non-institutionalized T2DM patients aged>65 years. The recommended personalized HbA1c targets were<7%, <8% and <9% for healthy, ill and very ill patients, respectively. Major clinical events (death from any cause, major vascular events and/or hospitalization) were recorded during the 3-year follow-up. Mixed-effects logistic regression models were used for the analyses. RESULTS: Of the 747 patients analyzed at baseline, 551 (76.8%) were at their recommended personalized HbA1c target. During follow-up, 391 patients (52.3%) experienced a major clinical event. Of the patients who did not achieve their personalized HbA1c target (compared with those who did), the risk (OR) of a major clinical event was 0.95 (95% CI: 0.69-1.31; P=0.76). The risk of death, major vascular event and hospitalization were 0.88 (95% CI: 0.40-1.94; P=0.75), 1.14 (95% CI: 0.7-1.83; P=0.59) and 0.84 (95% CI: 0.60-1.18; P=0.32), respectively. CONCLUSION: Over a 3-year follow-up period, our results showed no difference in risk of a major clinical event among patients, regardless of whether or not they achieved their personalized recommended HbA1c target. These results need to be confirmed before implementing a more permissive strategy for treating T2DM in elderly patients.


Asunto(s)
Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hemoglobina Glucada/análisis , Hipoglucemiantes/uso terapéutico , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Estudios Prospectivos
13.
Nat Commun ; 8(1): 1408, 2017 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-29123117

RESUMEN

The internal structure of nucleons (protons and neutrons) remains one of the greatest outstanding problems in modern nuclear physics. By scattering high-energy electrons off a proton we are able to resolve its fundamental constituents and probe their momenta and positions. Here we investigate the dynamics of quarks and gluons inside nucleons using deeply virtual Compton scattering (DVCS)-a highly virtual photon scatters off the proton, which subsequently radiates a photon. DVCS interferes with the Bethe-Heitler (BH) process, where the photon is emitted by the electron rather than the proton. We report herein the full determination of the BH-DVCS interference by exploiting the distinct energy dependences of the DVCS and BH amplitudes. In the regime where the scattering is expected to occur off a single quark, measurements show an intriguing sensitivity to gluons, the carriers of the strong interaction.

14.
Leukemia ; 10(11): 1719-23, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8892674

RESUMEN

We have analyzed the sequence of 40 VDJ rearrangements of the immunoglobulin heavy chain gene locus on 32 unselected children from Chile with precursor B cell ALL at diagnosis. Rearrangements were derived by PCR with VH gene family-specific primers and sequenced directly. The number of VDJ rearrangements, and the pattern of VH, DH and JH gene usage was identical to the one reported by groups from developed countries. CDR3 regions represented an unbiased repertoire; VH to JH joinings were in frame in 36% of cases. Absent N nucleotides in the DJ border, suggestive of fetal origin of ALL, were seen in 9/40 rearrangements but they did not correlate with younger age. More than one rearrangement was sequenced in six patients, representing independent events with no signs of clonal evolution. One patient was analyzed at first bone marrow relapse showing persistence of one rearrangement and evolution of a second one which conserved the DJ border. The subset of B cell precursors which suffer malignant transformation to ALL appear to be common in different parts of the world.


Asunto(s)
Reordenamiento Génico de Linfocito B , Genes de Inmunoglobulinas , Cadenas Pesadas de Inmunoglobulina/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Adolescente , Secuencia de Bases , Niño , Preescolar , Chile , ADN Complementario , Femenino , Humanos , Región de Cambio de la Inmunoglobulina/genética , Lactante , Masculino , Datos de Secuencia Molecular , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología , Análisis de Secuencia de ADN
15.
Arthritis Care Res (Hoboken) ; 67(2): 151-60, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25302624

RESUMEN

OBJECTIVE: To investigate clinical efficacy and safety of 2 certolizumab pegol (CZP) maintenance dosing regimens plus methotrexate (MTX) in active rheumatoid arthritis (RA) patients achieving the American College of Rheumatology 20% improvement criteria (ACR20) after the CZP 200 mg every 2 weeks open-label run-in period. METHODS: DOSEFLEX (dosing flexibility) was a double-blind, placebo-controlled randomized study with an open-label run-in phase. During the run-in phase, all patients received CZP 400 mg (weeks 0, 2, and 4) and 200 mg every 2 weeks to week 16. Week 16 ACR20 responders were randomized 1:1:1 at week 18 to CZP 200 mg every 2 weeks, 400 mg every 4 weeks, or placebo. RESULTS: A total of 209 (of 333) patients were randomized at week 18 (CZP: 200 mg, n = 70; 400 mg, n = 70; placebo, n = 69). Groups had similar baseline characteristics (week 0). Week 34 ACR20 response rates were comparable between the CZP 200 mg every 2 weeks and the 400 mg every 4 weeks groups (67.1% versus 65.2%), which was significantly higher than placebo (44.9%; P = 0.009 and P = 0.017). ACR50/70 and remission criteria were met more frequently in CZP groups than placebo at week 34, with similar responses between anti-tumor necrosis factor-experienced and naive patients. Improvements from baseline Disease Activity Score in 28 joints using the erythrocyte sedimentation rate and Health Assessment Questionnaire disability index scores were maintained in CZP groups from week 16 to 34 while worsening on placebo. Adverse event (AE) rates in the double-blind phase were 62.9% versus 60.9% versus 62.3%; serious AE rates were 7.1% versus 2.9% versus 0.0% (CZP 200 mg, 400 mg, and placebo groups). CONCLUSION: In active RA patients with an incomplete MTX response, CZP 200 mg every 2 weeks and 400 mg every 4 weeks were comparable and better than placebo for maintaining clinical response to week 4 following a 16-week, open-label run-in phase.


Asunto(s)
Anticuerpos Monoclonales Humanizados/administración & dosificación , Antirreumáticos/administración & dosificación , Artritis Reumatoide/tratamiento farmacológico , Fragmentos Fab de Inmunoglobulinas/administración & dosificación , Inmunosupresores/administración & dosificación , Polietilenglicoles/administración & dosificación , Adulto , Anciano , Anticuerpos Monoclonales Humanizados/efectos adversos , Antirreumáticos/efectos adversos , Certolizumab Pegol , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Quimioterapia Combinada , Femenino , Humanos , Fragmentos Fab de Inmunoglobulinas/efectos adversos , Inmunosupresores/efectos adversos , Masculino , Metotrexato/uso terapéutico , Persona de Mediana Edad , Polietilenglicoles/efectos adversos , Resultado del Tratamiento
16.
J Nutr Health Aging ; 19(2): 219-27, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25651449

RESUMEN

UNLABELLED: Few epidemiologic studies have specifically focused on very old community dwelling population with atrial fibrillation (AF). The objectives of the AF-S.AGES cohort were to describe real-life therapeutic management of non-institutionalized elderly patients with AF according to age groups, i.e., 65-79 and ≥ 80 and to determine the main factors associated with anticoagulant treatment in both groups. METHODS: Observational study (N=1072) aged ≥ 65 years old, recruited by general practitioners. Characteristics of the sample were first evaluated in the overall sample and according to age (< 80 or ≥ 80 years) and to use of anticoagulant treatment at inclusion. Logistic models were used to analyze the determinants of anticoagulant prescription among age groups. RESULTS: Mean age was 78.0 (SD=6.5) years and 42% were ≥ 80 years. Nineteen percent had paroxysmal AF, 15% persistent, 56% permanent and 10% unknown type, 77% were treated with vitamin K antagonists (VKA), 17% with antiplatelet therapy with no differences between age groups. Rate-control drugs were more frequently used than rhythm-control drugs (55% vs. 37%, p < 0.001). VKA use was associated with permanent AF, younger age and cancer in patients ≥ 80 years old and with permanent AF and preserved functional autonomy in patients < 80 years old. Hemorrhagic scores were independently associated with non-use of VKA whereas thromboembolic scores were not associated with VKA use. CONCLUSIONS: In this elderly AF outpatient population, use of anticoagulant therapy was higher even after 80 years than in previous studies suggesting that recent international guidelines are better implemented in the elderly population.


Asunto(s)
Anticoagulantes/uso terapéutico , Fibrilación Atrial/terapia , Anciano , Anciano de 80 o más Años , Anticoagulantes/efectos adversos , Estudios de Cohortes , Femenino , Hemorragia/inducido químicamente , Hemorragia/diagnóstico , Humanos , Modelos Logísticos , Masculino , Inhibidores de Agregación Plaquetaria/efectos adversos , Inhibidores de Agregación Plaquetaria/uso terapéutico , Riesgo , Tromboembolia/inducido químicamente , Tromboembolia/diagnóstico , Vitamina K/antagonistas & inhibidores
17.
Biochimie ; 72(12): 889-91, 1990 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2128918

RESUMEN

The protein patterns of a bglY mutant and the isogenic wild-type strains were compared on 2-dimensional gel electrophoresis. The synthesis of at least 36 peptides was affected. This suggests a global but specific role on gene expression for the DNA-binding protein H1.


Asunto(s)
Proteínas Bacterianas/genética , Proteínas de Unión al ADN/genética , Escherichia coli/genética , Proteínas Bacterianas/aislamiento & purificación , Proteínas de Unión al ADN/aislamiento & purificación , Electroforesis en Gel Bidimensional , Regulación Bacteriana de la Expresión Génica , Genes , Genes Bacterianos , Mutación
18.
Biochimie ; 83(2): 235-41, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11278074

RESUMEN

In Escherichia coli, the H-NS protein plays an important role in the structure and the functioning of bacterial chromosome. A homologous protein has also been identified in several enteric bacteria and in closely related organisms such as Haemophilus influenzae. To get information on their structure and their function, we identified H-NS-like proteins in various microorganisms by different procedures. In silico analysis of their amino acid sequence and/or in vivo experiments provide evidence that more than 20 proteins belong to the same class of regulatory proteins. Moreover, large scale technologies demonstrate that, at least in E. coli, the loss of motility in hns mutants results from a lack of flagellin biosynthesis, due to the in vivo repression of flagellar gene expression. In contrast, several genes involved in adaptation to low pH are strongly induced in a H-NS deficient strain, resulting in an increased resistance to acidic stress. Finally, expression profiling and phenotypic analysis suggest that, unlike H-NS, its paralogous protein StpA does not play any role in these processes.


Asunto(s)
Proteínas Bacterianas/fisiología , Proteínas de Unión al ADN/fisiología , Bacterias Gramnegativas/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Secuencia Conservada , Bases de Datos Factuales , Perfilación de la Expresión Génica , Biblioteca Genómica , Datos de Secuencia Molecular , Mutagénesis , Análisis de Secuencia por Matrices de Oligonucleótidos , Fenotipo , Conformación Proteica , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico
19.
Clin Pharmacokinet ; 39(5): 369-82, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11108435

RESUMEN

OBJECTIVE: To investigate the distribution of meloxicam in the human knee joint and to compare it with the inhibition of cyclo-oxygenase (COX) activity in synovial cells. DESIGN: Prospective pharmacokinetic study and in vitro laboratory investigation. PATIENTS AND PARTICIPANTS: 42 male and female patients aged 26 to 85 years hospitalised for rheumatic disease and requiring a diagnostic and/or therapeutic knee puncture. METHODS: After a single oral dose of meloxicam 15mg, synovial fluid and blood samples were collected once per patient at various intervals after administration. Meloxicam concentrations were determined by a validated high performance liquid chromatography assay, protein binding by equilibrium dialysis, and pharmacokinetic parameters were calculated by noncompartmental analysis from the mean drug concentration-time profiles. The inhibitory effect of meloxicam on COX activity was investigated separately in unstimulated or interleukin-1beta-stimulated human synovial cells from osteoarthritic patients. RESULTS: Meloxicam was found in synovial fluid at the earliest sampling time (1 hour). Peak concentrations were reached approximately 6 hours postdose in both plasma (842 microg/L) and synovial fluid (320 microg/L). A plateau was observed after the distribution phase (6 hours), corresponding to a constant ratio of drug concentration between synovial fluid and plasma of about 0.47. This ratio was higher in patients with acute inflammation (0.58) than in those with no inflammation (0.38). Meloxicam was extensively bound to protein, mainly to serum albumin. The area under the drug concentration-time curve (AUC) in plasma was more than 2.5 times that in synovial fluid. The AUC for free meloxicam was similar in plasma and synovial fluid. The 50% inhibitory concentrations (IC50) for basal and stimulated COX activity in human synovial cells were 33.7 nmol/L (11.8 microg/L) and 2.0 nmol/L (0.70 microg/L), respectively. The free concentration of meloxicam in synovial fluid was higher than the IC50 for stimulated COX activity from 6 to 36 hours postdose. CONCLUSION: On the basis of free synovial concentrations and the IC50 for stimulated COX activity, meloxicam is expected to have a long duration of action. Inhibition of COX activity is expected to be more marked in inflamed synovium compared with non-inflamed synovium.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacocinética , Inhibidores de la Ciclooxigenasa/farmacocinética , Articulación de la Rodilla/metabolismo , Tiazinas/farmacocinética , Tiazoles/farmacocinética , Administración Oral , Adulto , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Difusión , Femenino , Humanos , Masculino , Meloxicam , Persona de Mediana Edad , Estudios Prospectivos , Unión Proteica , Líquido Sinovial/metabolismo , Tiazinas/administración & dosificación , Tiazinas/farmacología , Tiazoles/administración & dosificación , Tiazoles/farmacología
20.
Ann N Y Acad Sci ; 651: 480-3, 1992 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-1376065

RESUMEN

In order to quantitate a previously noted decrease in CD20 fluorescence intensity (FI) on B-CLL lymphocytes, binding capacities [BC x 10(3) +/- 1SD = number of antibodies bound per cell] were calculated. The mean (N = 5) BC x 10(3) +/- 1SD of CD20 reagents for normal B-PBL and B-CLL lymphocytes confirmed this observation. B-PBL and B-CLL were 56 +/- 11 and 61 +/- 14, and 19 +/- 15 and 18 +/- 16, respectively, for Leu 16 and B1. Although adequate compensation standards for the determination of CD5 and CD20 coexpression are not available, qualitatively, the density of CD5 on both normal B-PBL and B-CLL is less compared to the expression of CD5 by normal T cells. CD5 expression on B-CLL seems to be linked to the lower levels of CD20, whereas CD5 expression may appear to be absent on CLL lymphocytes expressing normal levels of CD20. Levels of CD20 in B-CLL suggest involvement of one or two genes (alleles) whose decreased expression may be linked to CD5 expression.


Asunto(s)
Antígenos CD/análisis , Antígenos de Diferenciación de Linfocitos B/análisis , Subgrupos de Linfocitos B/inmunología , Leucemia Linfocítica Crónica de Células B/inmunología , Antígenos CD19 , Antígenos CD20 , Sitios de Unión de Anticuerpos , Antígenos CD5 , Humanos , Valores de Referencia
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