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1.
J Hered ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869982

RESUMO

Plastomes are used in phylogenetic reconstructions because of their relatively conserved nature. Nonetheless, some limitations arise, particularly at lower taxonomic levels due to reduced interspecific polymorphisms and frequent hybridization events that result in unsolved phylogenies including polytomies and reticulate evolutionary patterns. Next-generation sequencing technologies allow access to genomic data and strongly supported phylogenies, yet biased topologies may be obtained due to insufficient taxon sampling. We analyse the hypothesis that intraspecific plastome diversity reflects biogeographic history and hybridization cycles among taxa. We generated twelve new plastome sequences covering distinct latitudinal locations of all species of subgenus Nothofagus from North Patagonia. Chloroplast genomes were assembled, annotated, and searched for simple sequence repeats (SSRs). Phylogenetic reconstructions included species and sampled locations. The six Nothofagus species analysed were of similar size and structure; only N. obliqua of subgenus Lophozonia, used as outgroup, presented slight differences in size. We detected a variable number of SSRs in distinct species and locations. Phylogenetic analyses of plastomes confirmed that subgenus Nothofagus organizes into two monophyletic clades each consisting of individuals of different species. We detected a geographic structure within subgenus Nothofagus and found evidence of local chloroplast sharing due to past hybridization, followed by adaptive introgression and ecological divergence. These contributions enrich the comprehension of transversal evolutionary mechanisms such as chloroplast capture and its implications for phylogenetic and phylogenomic analyses.

2.
Phys Chem Chem Phys ; 15(25): 10331-4, 2013 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-23715380

RESUMO

Controlled nanozeolite deposits are prepared by electrochemical techniques on a macroporous carbon support and binderless thin film electrodes of zeolite-templated carbon are synthesized using the deposits as templates. The obtained film electrodes exhibit extremely high area capacitance (10-12 mF cm(-2)) and ultrahigh rate capability in a thin film capacitor.

3.
J Med Imaging (Bellingham) ; 8(2): 024001, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33681408

RESUMO

Purpose: The reconstruction of positron emission tomography images is a computationally intensive task which benefits from the use of increasingly complex physical models. Aiming to reduce the computational burden by means of a reduced system matrix, we present a list mode reconstruction approach based on maximum likelihood-expectation maximization and a sliced mesh support. Approach: The reconstruction strategy uses a fully 3D projection along series of 2D meshes arranged in the axial plane of the scanner. These series of meshes describe the continuous volumetric activity using a piece-wise linear function interpolated from the mesh elements. The mesh support is automatically adapted to the underlying structure of the activity by means of a remeshing process. This process finds a high-quality compact mesh representation constrained to a controlled interpolation error. Results: The method is tested using a Monte Carlo simulation of a Hoffman brain phantom and a National Electrical Manufacturers Association image quality phantom acquisition, using different sets of statistics. The reconstructions are compared against a voxelized reconstruction under different conditions, achieving similar or superior results. The number of parameters needed to reconstruct the image in voxel and mesh support is also compared, and the mesh reconstruction permits to reduce the number of nodes used to represent a complex image. Conclusions: The proposed reconstruction strategy reduces the number of parameters needed to describe the activity distribution by more than one order of magnitude for similar voxel size and with similar accuracy than state-of-the-art methods.

4.
J Food Prot ; 70(12): 2741-8, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18095425

RESUMO

The aims of this study were to ascertain the population structure and antimicrobial susceptibility of Salmonella enterica serovars isolated in 2002 from food in 16 Spanish regions. Serovars were characterized by serotyping, phage typing, antimicrobial susceptibility, and pulsed-field gel electrophoresis (PFGE) typing, and 264 nonrelated strains were selected for further analysis. The main sources were eggs and their derivatives (21.6% of strains), poultry and related products (16.6%), and seafood (16.3%). High serotype diversity was detected (51 serotypes); the most common were Enteritidis (n = 96, 36.3%) and Typhimurium (n = 53, 20.1%), followed by a miscellaneous group of 49 different serotypes (n = 115, 43.5%). A 15% increase in Salmonella Enteritidis isolation was observed. Common phage types for Salmonella Enteritidis were PT1 (41.6% of isolates), PT4 (9.4%), PT6 (9.4%), and PT6a (9.4%), and common types for Salmonella Typhimurium were DTU302 (18.8%), DT104 (15.1%), and DT104B (13.2%). Salmonella Enteritidis strains were categorized into eight PFGE types with a similarity of 81 to 96%, and 73.9% of the strains were grouped into just one cluster. Salmonella Typhimurium isolates were divided into 13 PFGE types with a similarity of 64 to 86%, and one predominant clone contained 41.5% of the strains. Resistance rates for Salmonella Enteritidis, Salmonella Typhimurium, and the miscellaneous group were, respectively, 8.3, 69.8, and 13.9% for ampicillin, 3.1, 52.8, and 59% for streptomycin, 40.6, 22.6, and 10.4% for nalidixic acid, 15.6, 71.7, and 31.1% for tetracycline, 7.3, 18.8, and 9.5% for trimethoprim-sulfamethoxazole, 0, 50.9, and 4.3% for chloramphenicol, and 6.2, 71.7, and 17.4% for multiple (at least four) antimicrobials. All the strains remained susceptible to other beta-lactams and fluoroquinolones. Surveillance of S. enterica isolated from food is strongly recommended to reduce community exposure to antimicrobial resistant strains.


Assuntos
Antibacterianos/farmacologia , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Salmonella enterica/classificação , Salmonella enterica/efeitos dos fármacos , Técnicas de Tipagem Bacteriana , Tipagem de Bacteriófagos , Relação Dose-Resposta a Droga , Farmacorresistência Bacteriana , Farmacorresistência Bacteriana Múltipla , Ovos/microbiologia , Eletroforese em Gel de Campo Pulsado/métodos , Humanos , Testes de Sensibilidade Microbiana , Produtos Avícolas/microbiologia , Alimentos Marinhos/microbiologia , Sorotipagem , Espanha
5.
Euro Surveill ; 10(10): 7-8, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29208084

RESUMO

Even though shigellosis in Spain is rare, an indigenous outbreak is occasionally detected. We describe an outbreak in a school in Madrid caused by person-to-person transmission of Shigella sonnei. After the detection of Shigella sonnei in a stool sample from a 3 year old girl, an investigation at her school was initiated. Questionnaires were distributed to the parents of 520 pupils attending the school. A case was defined as a school case if it was the first case in a child's household, and as a household case if other members of the household had fallen ill first. We identified 88 cases (60 pupils and 28 of their family members). The attack rate (AR) was 12% in the school and 32% in the families. There was a significant association between higher AR and lower age. The outbreak lasted for two months. The length and the shape of the epidemic curve of the 60 cases in pupils suggests person-to-person transmission. Shigella sonnei isolated from 5 different cases were typed by pulsed field gel electrophoresis (PFGE) and was found to be an identical strain. The prolonged duration of the outbreak was probably due to delayed detection, and stopped as soon as control measures were introduced.

6.
Euro Surveill ; 10(10): 268-70, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16282643

RESUMO

Even though shigellosis in Spain is rare, an indigenous outbreak is occasionally detected. We describe an outbreak in a school in Madrid caused by person-to-person transmission of Shigella sonnei. After the detection of Shigella sonnei in a stool sample from a 3 year old girl, an investigation at her school was initiated. Questionnaires were distributed to the parents of 520 pupils attending the school. A case was defined as a school case if it was the first case in a child's household, and as a household case if other members of the household had fallen ill first. We identified 88 cases (60 pupils and 28 of their family members). The attack rate (AR) was 12% in the school and 32% in the families. There was a significant association between higher AR and lower age. The outbreak lasted for two months. The length and the shape of the epidemic curve of the 60 cases in pupils suggests person-to-person transmission. Shigella sonnei isolated from 5 different cases were typed by pulsed field gel electrophoresis (PFGE) and was found to be an identical strain. The prolonged duration of the outbreak was probably due to delayed detection, and stopped as soon as control measures were introduced.


Assuntos
Surtos de Doenças , Disenteria Bacilar/epidemiologia , Instituições Acadêmicas , Criança , Pré-Escolar , Disenteria Bacilar/prevenção & controle , Disenteria Bacilar/transmissão , Humanos , Espanha/epidemiologia , Inquéritos e Questionários
7.
CorSalud ; 11(2): 161-166, abr.-jun. 2019. graf
Artigo em Espanhol | LILACS | ID: biblio-1089728

RESUMO

RESUMEN Se presenta el caso de una paciente de 43 años, con antecedentes de salud aparente, hasta varias semanas previas a su ingreso, cuando comenzó a presentar síncopes precedidos de palpitaciones. Se realizó estudio electrofisiológico y se demostró precocidad en la porción distal del electrodo de registro de seno coronario, que corresponde a la vena cardíaca magna (interventricular anterior) y techo (summit) del ventrículo izquierdo. A pesar del excelente registro precoz se estudiaron estructuras vecinas como el tracto de salida del ventrículo izquierdo en la cúspide coronaria izquierda, aquí el mapeo eléctrico (pace mapping) no fue concordante total. En el sitio de la precocidad obtenida dentro del sistema venoso cardíaco se realizó mapeo concordante 100%, con una precocidad del catéter de ablación de -30 milisegundos. Se decidió ablación con incrementos progresivos de temperatura y potencia con corte de impedancia (termomapping) y se logró el éxito de la ablación sin reproducibilidad de la arritmia y excelente evolución posterior.


ABSTRACT The case of a 43-year-old female patient is presented, with an apparent history of good health, up to several weeks prior to admission, when she began to present syncopes preceded by palpitations. An electrophysiological study was performed and prematurity in the distal portion of the coronary sinus recording electrode was demonstrated, which corresponds to the great cardiac vein (anterior interventricular vein) and summit of the left ventricle. Despite the excellent early registration, neighboring structures were studied, such as the left ventricular outflow tract in the left coronary cusp, here the pace mapping was not totally concordant. At the site of the precocity obtained within the cardiac venous system, a 100% concordant mapping was achieved, with an ablation catheter's precocity of -30 milliseconds. The ablation was decided with progressive increases in temperature and power with thermomapping and the success of the ablation was achieved without reproducibility of the arrhythmia and excellent subsequent evolution.


Assuntos
Técnicas Eletrofisiológicas Cardíacas , Taquicardia Ventricular , Complexos Atriais Prematuros , Ablação por Radiofrequência
9.
Zoonoses Public Health ; 54(8): 294-300, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17894639

RESUMO

The present study is the first conducted in Spain to estimate the bacteriological herd prevalence of Salmonella enterica in fattening units and to describe the Salmonella serovar diversity on these farms using a sample representative of the entire swine population. For this purpose, 10 faecal samples were collected from 10 different pens containing pigs close to market weight in a total of 232 fattening units. Total sample size was proportionally distributed according to the fattener census in each of the regions of the country and all the samples were examined by culture of 25 g of faecal material. One hundred (43.1%) farms had at least one Salmonella-positive sample (95% CI: 37-49.1%). Salmonella enterica was detected in 290 (12.5%) pooled faecal floor samples (95% CI: 11.2-13.8%). The apparent herd prevalence of salmonellosis was similar among multi-site, finishing and farrow to finish farms. Overall, 24 different serovars were identified, with S. Typhimurium, S. Rissen and S. Derby being the most common both at herd and sample level. Results of phage typing were available for the 91 isolates of S. Typhimurium. A total number of 10 different phage types were identified, with DT 193 being the most frequent. Phage types DT 104, DT 104b and DT U302, which have been associated with several multi-resistant patterns, accounted for 23% and 29% of the Typhimurium total isolates or Typhimurium infected farms respectively.


Assuntos
Salmonelose Animal/epidemiologia , Salmonella enterica , Doenças dos Suínos/epidemiologia , Animais , Reservatórios de Doenças , Fezes/microbiologia , Humanos , Carne , Prevalência , Salmonelose Animal/sangue , Salmonelose Animal/etiologia , Salmonelose Animal/transmissão , Salmonella enterica/classificação , Salmonella enterica/isolamento & purificação , Sorotipagem , Espanha/epidemiologia , Suínos , Doenças dos Suínos/sangue , Doenças dos Suínos/etiologia , Doenças dos Suínos/transmissão , Zoonoses
10.
J Trop Pediatr ; 52(1): 66-8, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16000342

RESUMO

The differential diagnosis of chronic diarrhea is extensive and requires the investigation of several diseases, such as celiac disease, inflammatory bowel disease and irritable bowel syndrome. A few patients infected by Trichuris trichiura may present a chronic dysentery-like syndrome in the context of a massive infestation of the colon leading to anemia and growth retardation, but the rarity of that finding demands a high level of suspicion. Herein we report the case of an 8-year-old boy from the rural zone who had suffered diarrhea without blood or mucus for 4 years and was taken to our Service because his mother had noticed the presence of blood on the feces on the 3 previous months. The diagnosis of a massive Trichuris trichiura infestation as the cause of the process was only reached by colonoscopy. We stress that Trichuris trichiura infection can mimic other forms of inflammatory bowel disease and lead to physical growth retardation and that prolonged regimens of albendazole may be required to the effective treatment of massive infestations.


Assuntos
Disenteria Amebiana/etiologia , Tricuríase/complicações , Trichuris/isolamento & purificação , Animais , Brasil , Criança , Doença Crônica , Colonoscopia , Disenteria Amebiana/diagnóstico , Disenteria Amebiana/terapia , Humanos , Masculino , Prognóstico , Medição de Risco , Índice de Gravidade de Doença , Tricuríase/diagnóstico
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