166 research outputs found
Horizontal gene transfer, dispersal and haloarchaeal speciation
The Halobacteria are a well-studied archaeal class and numerous investigations are showing how their diversity is distributed amongst genomes and geographic locations. Evidence indicates that recombination between species continuously facilitates the arrival of new genes, and within species, it is frequent enough to spread acquired genes amongst all individuals in the population. To create permanent independent diversity and generate new species, barriers to recombination are probably required. The data support an interpretation that rates of evolution (e.g., horizontal gene transfer and mutation) are faster at creating geographically localized variation than dispersal and invasion are at homogenizing genetic differences between locations. Therefore, we suggest that recurrent episodes of dispersal followed by variable periods of endemism break the homogenizing forces of intrapopulation recombination and that this process might be the principal stimulus leading to divergence and speciation in Halobacteria
Perrault syndrome with neurological features in a compound heterozygote for two TWNK mutations : Overlap of TWNK-related recessive disorders
Altres ajuts: This research was supported with cofounding from the European Regional Development Fund (ERDF), "A way to make Europe") (to IdC); S2017/BMD‑3721‑RAREGENOMICS‑CM from the Consejería de Educación e Investigación de la Comunidad de Madrid (to MAMP).Background: Perrault syndrome is a rare autosomal recessive disorder that is characterized by the association of sensorineural hearing impairment and ovarian dysgenesis in females, whereas males have only hearing impairment. In some cases, patients present with a diversity of neurological signs. To date, mutations in six genes are known to cause Perrault syndrome, but they do not explain all clinically-diagnosed cases. In addition, the number of reported cases and the spectra of mutations are still small to establish conclusive genotype-phenotype correlations. Methods: Affected siblings from family SH19, who presented with features that were suggestive of Perrault syndrome, were subjected to audiological, neurological and gynecological examination. The genetic study included genotyping and haplotype analysis for microsatellite markers close to the genes involved in Perrault syndrome, whole-exome sequencing, and Sanger sequencing of the coding region of the TWNK gene. Results: Three siblings from family SH19 shared similar clinical features: childhood-onset bilateral sensorineural hearing impairment, which progressed to profound deafness in the second decade of life; neurological signs (spinocerebellar ataxia, polyneuropathy), with onset in the fourth decade of life in the two females and at age 20 years in the male; gonadal dysfunction with early cessation of menses in the two females. The genetic study revealed two compound heterozygous pathogenic mutations in the TWNK gene in the three affected subjects: c.85C>T (p.Arg29∗), previously reported in a case of hepatocerebral syndrome; and a novel missense mutation, c.1886C>T (p.Ser629Phe). Mutations segregated in the family according to an autosomal recessive inheritance pattern. Conclusions: Our results further illustrate the utility of genetic testing as a tool to confirm a tentative clinical diagnosis of Perrault syndrome. Studies on genotype-phenotype correlation from the hitherto reported cases indicate that patients with Perrault syndrome caused by TWNK mutations will manifest neurological signs in adulthood. Molecular and clinical characterization of novel cases of recessive disorders caused by TWNK mutations is strongly needed to get further insight into the genotype-phenotype correlations of a phenotypic continuum encompassing Perrault syndrome, infantile-onset spinocerebellar ataxia, and hepatocerebral syndrome
The dynamical mass of the white dwarf in XY Ari questions intermediate polar X-ray spectral models
We present a dynamical study of the eclipsing intermediate polar XY Ari based
on time-resolved near-infrared spectroscopy obtained with the EMIR spectrograph
on the 10.4-m Gran Telescopio Canarias. Using main sequence template spectra
taken with the same instrument setup as the target spectra, we measure a radial
velocity amplitude of the late K-type donor star km s.
We also obtain the rotational broadening of its photospheric lines
km s. From these and the eclipse
geometry, we derive a donor-to-white dwarf mass ratio , an orbital inclination and dynamical
masses and (). This result places the white dwarf in XY
Ari as one of the three most massive known in a cataclysmic variable.
Comparison with a number of white dwarf mass estimates from X-ray spectral
modelling indicates the necessity of a major revision of the cooling models
currently assumed for magnetic accretion in intermediate polars, as most of the
X-ray white dwarf masses lie significantly below the dynamical mass value.Comment: 9 pages, 4 figures, 5 tables, submitted for publication in MNRA
Ti-Catalyzed Straightforward Synthesis of Exocyclic Allenes
Exocyclic allenes constitute useful building blocks in organic synthesis and have recently been identified as key
intermediates in the synthesis of natural products. Here the first general method for the most straightforward synthesis of exocyclic allenes reported to date is presented. This method is based on the Barbier-type cyclization of propargyl halides catalyzed by titanium; a safe, abundant, and ecofriendly metal. The reaction proceeds under mild conditions compatible with different functional groups and provides good yields of five-, six-, and seven-membered carbocycles and nitrogen-containing heterocycles bearing an exocyclic allene group. Experimental evidence supporting the proposed reaction mechanism is also provided. Moreover, this procedure can be carried out in an enantioselective manner by using chiral titanocene(III) catalysts. The utility of this method has been proved in the synthesis of the natural alkaloid stemoamide
Linezolid for infective endocarditis. A structured approach based on a national database experience
Current data on the frequency and efficacy of linezolid (LNZ) in infective endocarditis (IE) are based on small retrospective series. We used a national database to evaluate the effectiveness of LNZ in IE. This is a retrospective study of IE patients in the Spanish GAMES database who received LNZ. We defined 3 levels of therapeutic impact: LNZ 50% of the total treatment, and > 50% of the LNZ doses prescribed in the first weeks of treatment), and LNZ ? 7 days not fulfilling the high-impact criteria (LNZ-NHI). Effectiveness of LNZ was assessed using propensity score matching and multivariate analysis of high-impact cases in comparison to patients not treated with LNZ from the GAMES database matched for age-adjusted comorbidity Charlson index, heart failure, renal failure, prosthetic and intracardiac IE device, left-sided IE, and Staphylococcus aureus. Primary outcomes were in-hospital mortality and one-year mortality. Secondary outcomes included IE complications and relapses
Ocean acidification along the 24.5°N section in the subtropical North Atlantic
9 páginas, 4 figuras.-- Proyecto CarbochangeOcean acidification is directly related to increasing atmospheric CO2 levels due to human activities and the active role of the global ocean in absorbing part of this anthropogenic CO2. Here we present an assessment of the pH changes that have occurred along 24.5°N in the subtropical North Atlantic through comparison of pH observations conducted in 1992 and 2011. It reveals an overall decline in pH values in the first 1000 dbar of the water column. The deconvolution of the temporal pH differences into anthropogenic and nonanthropogenic components reveals that natural variability, mostly owed to a decrease in oxygen levels in particular regions of the section, explains the vertical distribution of the larger pH decreases (up to −0.05 pH units), which are found within the permanent thermocline. The detection of long-term trends in dissolved oxygen in the studied region gains importance for future pH projections, as these changes modulate the anthropogenically derived acidification. The anthropogenic forcing explains significant acidification deeper than 1000 dbar in the western basin, within the Deep Western Boundary Current.We acknowledge funding from
the Spanish Ministry of Economy and
Competitiveness through grants
CSD2008-00077 (Circumnavigation
Expedition MALASPINA 2010 Project),
CTM2009-08849 (ACDC Project), and
CTM2012-32017 (MANIFEST Project)
and from the Seventh Framework
Programme FP7 CARBOCHANGE (grant
agreement 264879). E.F. Guallart was
funded by CSIC through a JAE-Pre grant.Peer reviewe
Role of age and comorbidities in mortality of patients with infective endocarditis
Purpose: The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality.
Methods: Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015. Patients were stratified into three age groups:<65 years, 65 to 80 years, and = 80 years.The area under the receiver-operating characteristic (AUROC) curve was calculated to quantify the diagnostic accuracy of the CCI to predict mortality risk.
Results: A total of 3120 patients with IE (1327 < 65 years;1291 65-80 years;502 = 80 years) were enrolled.Fever and heart failure were the most common presentations of IE, with no differences among age groups.Patients =80 years who underwent surgery were significantly lower compared with other age groups (14.3%, 65 years; 20.5%, 65-79 years; 31.3%, =80 years). In-hospital mortality was lower in the <65-year group (20.3%, <65 years;30.1%, 65-79 years;34.7%, =80 years;p < 0.001) as well as 1-year mortality (3.2%, <65 years; 5.5%, 65-80 years;7.6%, =80 years; p = 0.003).Independent predictors of mortality were age = 80 years (hazard ratio [HR]:2.78;95% confidence interval [CI]:2.32–3.34), CCI = 3 (HR:1.62; 95% CI:1.39–1.88), and non-performed surgery (HR:1.64;95% CI:11.16–1.58).When the three age groups were compared, the AUROC curve for CCI was significantly larger for patients aged <65 years(p < 0.001) for both in-hospital and 1-year mortality.
Conclusion: There were no differences in the clinical presentation of IE between the groups. Age = 80 years, high comorbidity (measured by CCI), and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in the <65-year group
La secuenciación masiva dirigida revela que los pacientes con leucemia linfática crónica y reordenamiento de igh presentan mutaciones en los genes POT1, EGR2, BRAF, IGLL5 Y MGA
Abstract [CO-081]
Introducción: La traslocación de la región 14q32, que contiene el gen de la cadena pesada de las inmunoglobulinas (IGH), aparece en el 4-9% de pacientes de leucemia linfática crónica(LLC). Aunque algunos estudios le atribuyen a este subgrupo un pronóstico desfavorable, sus características clínicas y biológicas no se conocen en profundidad. La secuenciación masiva (NGS) ha mejorado notablemente el conocimiento de la heterogeneidad genética y clínica de la LLC, por lo que nos planteamos el análisis del perfil mutacional de estos pacientes para definir mejor su pronóstico.
Métodos: Se analizaron 231 pacientes de LLC, de los cuales 42 presentaban traslocación de 14q32. En todos los casos se disponía de datos clínicos y FISH. Se diseñó un panel personalizado de 54 genes, seleccionados por su frecuencia e implicación en la patogenia de la enfermedad. La secuenciación se realizó en la plataforma NextSeq(Illumina). El panel cubre el 97% de las regiones (>100X) con una profundidad de 606 lecturas/base, permitiendo la detección de variantes presentes en >3% de las células..
Dental Health and Mortality in People With End-Stage Kidney Disease Treated With Hemodialysis: A Multinational Cohort Study
Background Dental disease is more extensive in adults with chronic kidney disease, but whether dental health and behaviors are associated with survival in the setting of hemodialysis is unknown. Study Design Prospective multinational cohort. Setting & Participants 4,205 adults treated with long-term hemodialysis, 2010 to 2012 (Oral Diseases in Hemodialysis [ORAL-D] Study). Predictors Dental health as assessed by a standardized dental examination using World Health Organization guidelines and personal oral care, including edentulousness; decayed, missing, and filled teeth index; teeth brushing and flossing; and dental health consultation. Outcomes All-cause and cardiovascular mortality at 12 months after dental assessment. Measurements Multivariable-adjusted Cox proportional hazards regression models fitted with shared frailty to account for clustering of mortality risk within countries. Results During a mean follow-up of 22.1 months, 942 deaths occurred, including 477 cardiovascular deaths. Edentulousness (adjusted HR, 1.29; 95% CI, 1.10-1.51) and decayed, missing, or filled teeth score ≥ 14 (adjusted HR, 1.70; 95% CI, 1.33-2.17) were associated with early all-cause mortality, while dental flossing, using mouthwash, brushing teeth daily, spending at least 2 minutes on oral hygiene daily, changing a toothbrush at least every 3 months, and visiting a dentist within the past 6 months (adjusted HRs of 0.52 [95% CI, 0.32-0.85], 0.79 [95% CI, 0.64-0.97], 0.76 [95% CI, 0.58-0.99], 0.84 [95% CI, 0.71-0.99], 0.79 [95% CI, 0.65-0.95], and 0.79 [95% CI, 0.65-0.96], respectively) were associated with better survival. Results for cardiovascular mortality were similar. Limitations Convenience sample of clinics. Conclusions In adults treated with hemodialysis, poorer dental health was associated with early death, whereas preventive dental health practices were associated with longer survival
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