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1.
Ultrasound Obstet Gynecol ; 63(2): 214-221, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37519145

RESUMO

OBJECTIVES: To ascertain whether abnormalities in neonatal head circumference and/or body weight are associated with levels of angiogenic/antiangiogenic factors in the maternal and cord blood of pregnancies with a congenital heart defect (CHD) and to assess whether the specific type of CHD influences this association. METHODS: This was a multicenter case-control study of women carrying a fetus with major CHD. Recruitment was carried out between June 2010 and July 2018 at four tertiary care hospitals in Spain. Maternal venous blood was drawn at study inclusion and at delivery. Cord blood samples were obtained at birth when possible. Placental growth factor (PlGF), soluble fms-like tyrosine kinase-1 (sFlt-1) and soluble endoglin (sEng) were measured in maternal and cord blood. Biomarker concentrations in the maternal blood were expressed as multiples of the median (MoM). RESULTS: PlGF, sFlt-1 and sEng levels were measured in the maternal blood in 237 cases with CHD and 260 healthy controls, and in the cord blood in 150 cases and 56 controls. Compared with controls, median PlGF MoM in maternal blood was significantly lower in the CHD group (0.959 vs 1.022; P < 0.0001), while median sFlt-1/PlGF ratio MoM was significantly higher (1.032 vs 0.974; P = 0.0085) and no difference was observed in sEng MoM (0.981 vs 1.011; P = 0.4673). Levels of sFlt-1 and sEng were significantly higher in cord blood obtained from fetuses with CHD compared to controls (mean ± standard error of the mean, 447 ± 51 vs 264 ± 20 pg/mL; P = 0.0470 and 8.30 ± 0.92 vs 5.69 ± 0.34 ng/mL; P = 0.0430, respectively). Concentrations of sFlt-1 and the sFlt-1/PlGF ratio in the maternal blood at study inclusion were associated negatively with birth weight and head circumference in the CHD group. The type of CHD anomaly (valvular, conotruncal or left ventricular outflow tract obstruction) did not appear to alter these findings. CONCLUSIONS: Pregnancies with fetal CHD have an antiangiogenic profile in maternal and cord blood. This imbalance is adversely associated with neonatal head circumference and birth weight. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Cardiopatias Congênitas , Pré-Eclâmpsia , Gravidez , Recém-Nascido , Feminino , Humanos , Fator de Crescimento Placentário , Peso ao Nascer , Sangue Fetal , Estudos de Casos e Controles , Biomarcadores , Endoglina , Fator A de Crescimento do Endotélio Vascular , Receptor 1 de Fatores de Crescimento do Endotélio Vascular
2.
Proc Natl Acad Sci U S A ; 116(25): 12363-12372, 2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-31164419

RESUMO

The first historically documented pandemic caused by Yersinia pestis began as the Justinianic Plague in 541 within the Roman Empire and continued as the so-called First Pandemic until 750. Although paleogenomic studies have previously identified the causative agent as Y. pestis, little is known about the bacterium's spread, diversity, and genetic history over the course of the pandemic. To elucidate the microevolution of the bacterium during this time period, we screened human remains from 21 sites in Austria, Britain, Germany, France, and Spain for Y. pestis DNA and reconstructed eight genomes. We present a methodological approach assessing single-nucleotide polymorphisms (SNPs) in ancient bacterial genomes, facilitating qualitative analyses of low coverage genomes from a metagenomic background. Phylogenetic analysis on the eight reconstructed genomes reveals the existence of previously undocumented Y. pestis diversity during the sixth to eighth centuries, and provides evidence for the presence of multiple distinct Y. pestis strains in Europe. We offer genetic evidence for the presence of the Justinianic Plague in the British Isles, previously only hypothesized from ambiguous documentary accounts, as well as the parallel occurrence of multiple derived strains in central and southern France, Spain, and southern Germany. Four of the reported strains form a polytomy similar to others seen across the Y. pestis phylogeny, associated with the Second and Third Pandemics. We identified a deletion of a 45-kb genomic region in the most recent First Pandemic strains affecting two virulence factors, intriguingly overlapping with a deletion found in 17th- to 18th-century genomes of the Second Pandemic.


Assuntos
Surtos de Doenças/história , Genoma Bacteriano , Peste/microbiologia , Yersinia pestis/genética , Europa (Continente)/epidemiologia , História Medieval , Humanos , Peste/epidemiologia , Peste/história , Yersinia pestis/patogenicidade
3.
BMC Pediatr ; 19(1): 326, 2019 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-31506079

RESUMO

BACKGROUND: Congenital heart disease (CHD) is the most prevalent congenital malformation affecting 1 in 100 newborns. While advances in early diagnosis and postnatal management have increased survival in CHD children, worrying long-term outcomes, particularly neurodevelopmental disability, have emerged as a key prognostic factor in the counseling of these pregnancies. METHODS: Eligible participants are women presenting at 20 to < 37 weeks of gestation carrying a fetus with CHD. Maternal/neonatal recordings are performed at regular intervals, from the fetal period to 24 months of age, and include: placental and fetal hemodynamics, fetal brain magnetic resonance imaging (MRI), functional echocardiography, cerebral oxymetry, electroencephalography and serum neurological and cardiac biomarkers. Neurodevelopmental assessment is planned at 12 months of age using the ages and stages questionnaire (ASQ) and at 24 months of age with the Bayley-III test. Target recruitment is at least 150 cases classified in three groups according to three main severe CHD groups: transposition of great arteries (TGA), Tetralogy of Fallot (TOF) and Left Ventricular Outflow Tract Obstruction (LVOTO). DISCUSSION: The results of NEURO-HEART study will provide the most comprehensive knowledge until date of children's neurologic prognosis in CHD and will have the potential for developing future clinical decisive tools and improving preventive strategies in CHD. TRIAL REGISTRATION: NCT02996630 , on 4th December 2016 (retrospectively registered).


Assuntos
Desenvolvimento Infantil , Ensaios Clínicos como Assunto , Cardiopatias Congênitas/complicações , Transtornos do Neurodesenvolvimento/etiologia , Biomarcadores/sangue , Ecocardiografia , Feminino , Idade Gestacional , Cardiopatias Congênitas/sangue , Humanos , Lactente , Imageamento por Ressonância Magnética , Transtornos do Neurodesenvolvimento/diagnóstico por imagem , Avaliação de Resultados em Cuidados de Saúde , Gravidez , Prognóstico , Estudos Prospectivos
4.
Ultrasound Obstet Gynecol ; 52(6): 734-738, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29205570

RESUMO

OBJECTIVE: To assess potential differences in the expression of antiangiogenic and angiogenic factors and of genes associated with chronic hypoxia in cerebral tissue of euploid fetuses with congenital heart disease (CHD) vs those without. METHODS: Cerebral tissue was obtained from 15 fetuses with CHD and 12 control fetuses that had undergone termination of pregnancy. Expression profiles of the antiangiogenic factor soluble fms-like tyrosine kinase-1 (sFlt-1), the angiogenic vascular endothelial growth factor-A (VEGF-A) and placental growth factor (PlGF), and of genes associated with chronic hypoxia were determined by real-time polymerase chain reaction in tissue from the frontal cortex and the basal ganglia of the fetuses. RESULTS: Expression of sFlt-1 was 48% higher in the frontal cortex (P = 0.0431) and 72% higher in the basal ganglia (P = 0.0369) of CHD fetuses compared with controls. The expression of VEGF-A was 60% higher (P = 0.0432) and that of hypoxia-inducible factor 2-alpha was 98% higher (P = 0.0456) in the basal ganglia of CHD fetuses compared with controls. No significant differences were observed between the two groups in the expression of PlGF and hypoxia-inducible factor 1-alpha. CONCLUSION: An overall dysregulation of angiogenesis with a net balance towards an antiangiogenic environment was observed in the cerebral tissue of fetuses with CHD, suggesting that these fetuses may have an intrinsic angiogenic impairment that could contribute to impaired brain perfusion and abnormal neurological development later in life. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Gânglios da Base/embriologia , Lobo Frontal/embriologia , Cardiopatias Congênitas/genética , Fator de Crescimento Placentário/genética , Fator A de Crescimento do Endotélio Vascular/genética , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Adulto , Gânglios da Base/química , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Feminino , Lobo Frontal/química , Perfilação da Expressão Gênica , Humanos , Hipóxia/genética , Gravidez , Regulação para Cima
5.
Mol Phylogenet Evol ; 114: 122-136, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28624516

RESUMO

Quaternary glacial cycles drove major shifts in both the extent and location of the geographical ranges of many organisms. During glacial maxima, large areas of central and northern Europe were inhospitable to temperate species, and these areas are generally assumed to have been recolonized during interglacials by range expansions from Mediterranean refugia. An alternative is that this recolonization was from non-Mediterranean refugia, in central Europe or western Asia, but data on the origin of widespread central and north European species remain fragmentary, especially for insects. We studied three widely distributed lineages of freshwater beetles (the Platambus maculatus complex, the Hydraena gracilis complex, and the genus Oreodytes), all restricted to running waters and including both narrowly distributed southern endemics and widespread European species, some with distributions spanning the Palearctic. Our main goal was to determine the role of the Pleistocene glaciations in shaping the diversification and current distribution of these lineages. We sequenced four mitochondrial and two nuclear genes in populations drawn from across the ranges of these taxa, and used Bayesian probabilities and Maximum Likelihood to reconstruct their phylogenetic relationships, age and geographical origin. Our results suggest that all extant species in these groups are of Pleistocene origin. In the H. gracilis complex, the widespread European H. gracilis has experienced a rapid, recent range expansion from northern Anatolia, to occupy almost the whole of Europe. However, in the other two groups widespread central and northern European taxa appear to originate from central Asia, rather than the Mediterranean. These widespread species of eastern origin typically have peripherally isolated forms in the southern Mediterranean peninsulas, which may be remnants of earlier expansion-diversification cycles or result from incipient isolation of populations during the most recent Holocene expansion. The accumulation of narrow endemics of such lineages in the Mediterranean may result from successive cycles of range expansion, with subsequent speciation (and local extinction in glaciated areas) through multiple Pleistocene climatic cycles.


Assuntos
Besouros/classificação , Animais , Ásia Ocidental , Sequência de Bases , Teorema de Bayes , Besouros/genética , Complexo IV da Cadeia de Transporte de Elétrons/classificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Europa (Continente) , Variação Genética , Histonas/classificação , Histonas/genética , Filogenia , RNA Ribossômico 16S/classificação , RNA Ribossômico 16S/genética , Refúgio de Vida Selvagem
6.
Ultrasound Obstet Gynecol ; 49(3): 379-386, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27214694

RESUMO

OBJECTIVES: To determine the longitudinal behavior of fetal biometric measures and cerebroplacental hemodynamics throughout gestation in fetuses with congenital heart disease (CHD). METHODS: Fetal biometry and Doppler hemodynamics (uterine artery (UtA), umbilical artery (UA) and fetal middle cerebral artery (MCA)) were measured serially in a cohort of consecutive fetuses diagnosed with CHD. Evaluations were made at various time points, from diagnosis (20-25 weeks) to delivery, with at least two measurements per fetus that were at least 2 weeks apart. Fetuses were classified into three groups according to the pattern of blood supply to the brain (placental vs systemic) that would be expected on the basis of the type of CHD. All parameters were transformed into Z-scores. A linear mixed model to analyze repeated measurements was constructed for each parameter to assess its behavior throughout gestation. RESULTS: Four hundred and forty-four ultrasound examinations were performed in 119 CHD fetuses, with a median of two measurements per fetus. The fetuses presented a small head at diagnosis (biparietal diameter (BPD) Z-score, -1.32 ± 0.99; head circumference (HC) Z-score, -0.79 ± 1.02), which remained small throughout gestation. UtA and UA pulsatility indices (PI) showed a significant increase towards the end of pregnancy, whereas no significant changes were observed in MCA-PI or cerebroplacental ratio (CPR) with gestational age. Both MCA and CPR presented significant differences in longitudinal behavior between CHD groups, while BPD and HC did not. CONCLUSIONS: CHD fetuses have a relatively small head from the second trimester of pregnancy, regardless of the type of CHD anomaly, and increasing resistance in the UtA and UA as pregnancy progresses, suggestive of increasing degree of placental impairment. Our findings indicate the early onset of mechanisms that could lead to poorer neurodevelopment later in life. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Biometria/métodos , Cardiopatias Congênitas/diagnóstico por imagem , Artéria Cerebral Média/diagnóstico por imagem , Artérias Umbilicais/diagnóstico por imagem , Artéria Uterina/diagnóstico por imagem , Feminino , Hemodinâmica , Humanos , Idade Materna , Artéria Cerebral Média/embriologia , Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Ultrassonografia Pré-Natal/métodos , Artérias Umbilicais/embriologia , Artéria Uterina/embriologia , Adulto Jovem
7.
Heredity (Edinb) ; 116(1): 114-23, 2016 01.
Artigo em Inglês | MEDLINE | ID: mdl-26328758

RESUMO

Physiological changes associated with evolutionary and ecological processes such as diversification, range expansion or speciation are still incompletely understood, especially for non-model species. Here we study differences in protein expression in response to temperature in a western Mediterranean diving beetle species complex, using two-dimensional differential gel electrophoresis with one Moroccan and one Iberian population each of Agabus ramblae and Agabus brunneus. We identified proteins with significant expression differences after thermal treatments comparing them with a reference EST library generated from one of the species of the complex (A. ramblae). The colonisation during the Middle Pleistocene of the Iberian peninsula by A. ramblae, where maximum temperatures and seasonality are lower than in the ancestral north African range, was associated with changes in the response to 27 °C in proteins related to energy metabolism. The subsequent speciation of A. brunneus from within populations of Iberian A. ramblae was associated with changes in the expression of several stress-related proteins (mostly chaperons) when exposed to 4 °C. These changes are in agreement with the known tolerance to lower temperatures of A. brunneus, which occupies a larger geographical area with a wider range of climatic conditions. In both cases, protein expression changes paralleled the evolution of thermal tolerance and the climatic conditions experienced by the species. However, although the colonisation of the Iberian peninsula did not result in morphological change, the speciation process of A. brunneus within Iberia involved genetic isolation and substantial differences in male genitalia and body size and shape.


Assuntos
Evolução Biológica , Clima , Besouros/genética , Proteínas de Insetos/genética , Temperatura , Animais , Besouros/classificação , Metabolismo Energético/genética , Masculino , Marrocos , Filogenia , Proteoma , Espanha
8.
Bioinformatics ; 27(3): 435-6, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21134893

RESUMO

UNLABELLED: Grass seeds are complex organs composed by multiple tissues and cell types that develop coordinately to produce a viable embryo. The identification of genes involved in seed development is of great interest, but systematic spatial analyses of gene expression on maize seeds at the cell level have not yet been performed. MASISH is an online database holding information for gene expression spatial patterns in maize seeds based on in situ hybridization experiments. The web-based query interface allows the execution of gene queries and provides hybridization images, published references and information of the analyzed genes. AVAILABILITY: http://masish.uab.cat/.


Assuntos
Biologia Computacional/métodos , Bases de Dados Genéticas , Regulação da Expressão Gênica de Plantas , Sementes/genética , Zea mays/genética , Perfilação da Expressão Gênica , Internet , Software
9.
Mol Phylogenet Evol ; 54(1): 97-106, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19853049

RESUMO

Trechini ground beetles include some of the most spectacular radiations of cave and endogean Coleoptera, but the origin of the subterranean taxa and their typical morphological adaptations (loss of eyes and wings, depigmentation, elongation of body and appendages) have never been studied in a formal phylogenetic framework. We provide here a molecular phylogeny of the Pyrenean subterranean Trechini based on a combination of mitochondrial (cox1, cyb, rrnL, tRNA-Leu, nad1) and nuclear (SSU, LSU) markers of 102 specimens of 90 species. We found all Pyrenean highly modified subterranean taxa to be monophyletic, to the exclusion of all epigean and all subterranean species from other geographical areas (Cantabrian and Iberian mountains, Alps). Within the Pyrenean subterranean clade the three genera (Geotrechus, Aphaenops and Hydraphaenops) were polyphyletic, indicating multiple origins of their special adaptations to different ways of life (endogean, troglobitic or living in deep fissures). Diversification followed a geographical pattern, with two main clades in the western and central-eastern Pyrenees respectively, and several smaller lineages of more restricted range. Based on a Bayesian relaxed-clock approach, and using as an approximation a standard mitochondrial mutation rate of 2.3% MY, we estimate the origin of the subterranean clade at ca. 10 MY. Cladogenetic events in the Pliocene and Pleistocene were almost exclusively within the same geographical area and involving species of the same morphological type.


Assuntos
Besouros/genética , Evolução Molecular , Filogenia , Algoritmos , Animais , Teorema de Bayes , Núcleo Celular/genética , Besouros/classificação , DNA Mitocondrial/genética , Meio Ambiente , França , Especiação Genética , Geografia , Alinhamento de Sequência , Análise de Sequência de DNA , Espanha
10.
Tob Prev Cessat ; 6: 55, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33083683

RESUMO

INTRODUCTION: We analyze the activities carried out by primary care (PC) physicians and nurses with respect to smoking cessation and evaluate their self-reported training, knowledge, and behavior. METHODS: A cross-sectional study was conducted including 1514 PC physicians and nurses from June 2016 to March 2017, in Spain. The main variable was Good Practice (GP) in attention to smokers. To identify associated factors, a multilevel logistic regression model was used adjusted for sex, age, type of center, contract, years of employment, tobacco consumption, and self-reported training/knowledge. RESULTS: Of the 792 physicians and 722 nurses, 48.6% referred to GP in smoking cessation management. The finding related to: being a non-smoker (OR=1.8; 95% CI: 1.2-2.5) or ex-smoker (OR=1.4; 95% CI: 1.02-2.1), having a good level of knowledge (OR=1.8; 95% CI: 1.3-2.4) and training (OR=2.4; 95% CI: 1.8-3.2), and, to a lesser extent, being female (OR=1.3; 95% CI: 1.03-1.7), and work experience >10 years (OR=1.4; 95% CI: 1.03-1.9). The main GP barriers were: lack of time (45.5%), organizational problems (48.4%), and 35.4% lack of training. CONCLUSIONS: The GP of PC physicians and nurses regarding smoking cessation management is related to being non-smokers or ex-smokers, and having sufficient training and knowledge. Lack of time and organizational problems were considered to be the main barriers. The promotion of training activities in the Spanish National Health Service with the support of scientific societies is required.

11.
Mol Ecol ; 18(18): 3885-902, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19702753

RESUMO

It has been hypothesized that species living in small lentic water bodies, because of the short-term geological persistence of their habitat, should show higher dispersal ability, with increased gene flow among populations and a less pronounced phylogeographical structure. Conversely, lotic species, living in more geologically stable habitats, should show reduced dispersal and an increased phylogeographical structure at the same geographical scales. In this work we tested the influence of habitat type in two groups of aquatic Coleoptera (Nebrioporus ceresyi and Ochthebius notabilis groups, families Dytiscidae and Hydraenidae respectively), each of them with closely related species typical of lotic and lentic saline Western Mediterranean water bodies. We used mitochondrial cox1 sequence data of 453 specimens of 77 populations through the range of nine species to compare a lotic vs. a lentic lineage in each of the two groups. Despite the differences in biology (predators vs. detritivorous) and evolutionary history, in both lotic lineages there was a higher proportion of nucleotide diversity among than within groups of populations, and a faster rate of accumulation of haplotype diversity (as measured by rarefaction curves) than in the lentic lineages. Similarly, lotic lineages had a higher absolute phylogenetic diversity, more remarkable considering their smaller absolute geographical ranges. By comparing closely related species, we were able to show the effect of contrasting habitat preferences in two different groups, in agreement with predictions derived from habitat stability.


Assuntos
Besouros/genética , Ecossistema , Genética Populacional , Filogenia , Animais , Besouros/classificação , DNA Mitocondrial/genética , Fluxo Gênico , Genes de Insetos , Variação Genética , Geografia , Haplótipos , Análise de Sequência de DNA
12.
Med Clin (Barc) ; 127(8): 286-8, 2006 Sep 02.
Artigo em Espanhol | MEDLINE | ID: mdl-16949011

RESUMO

BACKGROUND AND OBJECTIVE: Our goal was to describe the secondary prevention of coronary heart disease activities in two primary healthcare centers and to analyze differences according to gender. PATIENTS AND METHOD: Retrospective follow-up study (medical records audit) during one year of 187 patients discharged after one myocardial infarction to identify the use of preventive advice and treatments. RESULTS: Men had more exercise (66.7%), smoking (62.9%) and alcohol advice (20.0%) and less diet advice (62.9%) than women (34.3%, 2.9%, 0.0%, 94.3%, respectively). After one year of follow-up, there were no differences in antiplatelet therapy (99.3%), betablockers (41.4%) and statins (70.7%), yet the use of drugs with action on the renin-angiotensin system showed notable differences (men: 50.5%; women: 5.7%; P < .05). Overall, 66.6% of the men vs. 31.4 of the women received three or more treatments. There were no differences among health centers. CONCLUSIONS: Although secondary prevention seems to have improved along time, some problems remain, especially in women.


Assuntos
Doença das Coronárias/prevenção & controle , Infarto do Miocárdio/reabilitação , Atenção Primária à Saúde/estatística & dados numéricos , Idoso , Feminino , Humanos , Masculino , Auditoria Médica , Pessoa de Meia-Idade , Atenção Primária à Saúde/tendências , Estudos Retrospectivos , Fatores Sexuais , Espanha
13.
Gene ; 240(2): 355-9, 1999 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-10580155

RESUMO

The maize genomic DNA sequence encoding the eukaryotic translation initiation factor 5 (eIF-5) has been isolated from genomic library of maize seedlings and the exon-intron structure determined (accession number AJ132240). The length of genomic DNA sequenced was about 7kb and contained two exons with the translation start site in exon 2. The only intron is located in the non-coding 5' region and it is 1298bp long with the splice acceptor and donor sites conforming to the AG/GT rules. Repetitive sequence fragments are located in the 5' and 3' intergenic region. The accumulation of eIF-5 mRNA was studied by RNA blot and in situ hybridization. The observed distribution of mRNA may correlate with the function of the protein, as it appears to be highly abundant in tissues where the proportion of cells actively dividing is very high, such as meristematic regions.


Assuntos
Genes de Plantas/genética , Fatores de Iniciação de Peptídeos/genética , Zea mays/genética , Clonagem Molecular , DNA de Plantas/química , DNA de Plantas/genética , Fator de Iniciação 5 em Eucariotos , Éxons , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Hibridização In Situ , Íntrons , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sementes/genética , Análise de Sequência de DNA , Distribuição Tecidual , Zea mays/química , Zea mays/embriologia
14.
Proc Biol Sci ; 269(1507): 2351-6, 2002 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-12495503

RESUMO

The six extant aquatic families of Hydradephaga (Coleoptera) known so far represent a diverse group of beetles morphologically highly modified for life in the water. We report the discovery of a new genus with two species from South Africa and China, which differ greatly from all extant families, but resemble the Jurassic-Cretaceous dagger Liadytidae (the dagger symbol indicates that the taxa are known only as fossils). Based on a combined phylogenetic analysis of molecular and morphological data we erect a new family, Aspidytidae, which is the sister group of Dytiscidae plus Hygrobiidae. We propose a new scenario for the evolution of swimming behaviour in adephagan beetles, in which the transition into the aquatic environment is followed by complex and repeated changes in lifestyles, including the secondary complete loss of swimming ability in Aspidytidae.


Assuntos
Besouros/classificação , Besouros/genética , Água Doce , Animais , Evolução Biológica , China , Besouros/fisiologia , DNA Ribossômico/análise , Ecossistema , Feminino , Masculino , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular , Movimento , Filogenia , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , RNA Ribossômico 18S/genética , Análise de Sequência de DNA , África do Sul
15.
An Med Interna ; 21(3): 135-7, 2004 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-15043495

RESUMO

Kikuchi-Fujimoto disease or necrotizing histiocytic lymphadenitis is a self-limited process of lymphatic system that affects more frequently young women. Fever and adenopathy, often cervical, are typical. Diagnosis is fundamentally based on the affected lymph node biopsy, since laboratory data are often normal. It's a very rare entity in Spain, being more frequent in Oriental countries. It's a benign evolution process, with a spontaneous healing in some weeks or months. This is the reason because of this disease could be infradiagnosed. It's very important the differential diagnosis with malignant lymphomas, because Kikuchi-Fujimoto disease doesn't need any treatment.


Assuntos
Linfadenite Histiocítica Necrosante/virologia , Caxumba/complicações , Adulto , Anticorpos Antivirais/análise , Linfadenite Histiocítica Necrosante/diagnóstico , Linfadenite Histiocítica Necrosante/terapia , Humanos , Linfonodos/patologia , Masculino , Caxumba/imunologia , Caxumba/terapia , Vírus da Caxumba/imunologia
16.
Biochem Biophys Res Commun ; 236(2): 510-6, 1997 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-9240471

RESUMO

A maize cDNA encoding the eukaryotic translation initiation factor 5 (eIF-5) has been isolated from an 8-day-old seedling cDNA library. The 1975 bp cDNA encodes a protein of 451 amino acids, with a predicted molecular weight of 49.04 kDa, and hybridizes to a single sequence in the maize genome. The deduced sequence contains motifs characteristic of proteins belonging to the GPTase superfamily, a zinc finger well conserved in all the protein sequences for eIF-5 reported so far, and a fragment also present in prokaryotic and chloroplast L11 ribosomal protein. Polymer-binding assays have been used to assess the predicted RNA binding property of the protein and to characterize its function. It is shown that the eIF-5-encoded protein binds to single-stranded DNA and to polyuridylic acid and that the binding is dependent on the presence of Zn2+ ions. These results suggest that the zinc-finger structure is involved in the binding of the eIF-5 protein to RNA.


Assuntos
Fatores de Iniciação de Peptídeos/metabolismo , Proteínas de Ligação a RNA/metabolismo , Sequência de Aminoácidos , Clonagem Molecular , Fator de Iniciação 5 em Eucariotos , Dados de Sequência Molecular , Proteínas de Plantas/metabolismo , Ligação Proteica , RNA/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Zea mays , Zinco/metabolismo , Dedos de Zinco
17.
Mol Ecol ; 12(1): 153-67, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12492885

RESUMO

The phylogeny and population history of Meladema diving beetles (Coleoptera, Dytiscidae) were examined using mitochondrial DNA sequence from 16S ribosomal RNA and cytochrome oxidase I genes in 51 individuals from 22 populations of the three extant species (M. imbricata endemic to the western Canary Islands, M. lanio endemic to Madeira and M. coriacea widespread in the Western Mediterranean and on the western Canaries), using a combination of phylogenetic and nested clade analyses. Four main lineages are observed within Meladema, representing the three recognized species plus Corsican populations of M. coriacea. Phylogenetic analyses demonstrate the sister relationship of the two Atlantic Island taxa, and suggest the possible paraphyly of M. coriacea. A molecular clock approach reveals that speciation within the genus occurred in the Early Pleistocene, indicating that the Atlantic Island endemics are not Tertiary relict taxa as had been proposed previously. Our results point to past population bottlenecks in all four lineages, with recent (Late-Middle Pleistocene) range expansion in non-Corsican M. coriacea and M. imbricata. Within the Canary Islands, M. imbricata seems to have independently colonized La Gomera and La Palma from Tenerife (although a colonization of La Palma from La Gomera cannot be discarded), and M. coriacea has independently colonized Tenerife and Gran Canaria from separate mainland lineages. In the Mediterranean basin this species apparently colonized Corsica on a single occasion, relatively early in its evolutionary history (Early Pleistocene), and has colonized Mallorca recently on multiple occasions. On the only island where M. coriacea and M. imbricata are broadly sympatric (Tenerife), we report evidence of bidirectional hybridization between the two species.


Assuntos
Evolução Biológica , Besouros/classificação , Besouros/genética , DNA Mitocondrial/análise , Animais , Ilhas Atlânticas , Besouros/fisiologia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Variação Genética , Genética Populacional , Funções Verossimilhança , Região do Mediterrâneo , Filogenia , Portugal , RNA Ribossômico 16S/genética
18.
Mol Ecol ; 10(3): 721-35, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11298983

RESUMO

Most aquatic beetles in the family Dytiscidae are tightly associated either with running (lotic) or stagnant (lentic) water bodies. The range size of lotic species is known to be, on average, much smaller than that of lentic species, presumably as a result of differences in dispersal strategies in each habitat type. We explored possible effects of these differences on clade evolution and speciation rates by comparing species-level phylogenies based on cytochrome oxidase I (COI) and 16S rRNA mitochondrial genes for two genera, the lentic Ilybius and the lotic Deronectes. The expectation that species turnover is higher in lotic lineages due to their lower dispersal propensity compared to lentic species was not strongly supported. Deronectes displays a higher frequency of recent splits than Ilybius, consistent with the hypothesis, but the difference was not significant compared to expected patterns under a constant speciation rate null model. Similarly, when the degree of sympatry was plotted against relative node age, more allopatric splits were evident in the lentic Deronectes, suggesting a slower rate of range movement since speciation, but the differences were not significant. We discuss two explanations for our failure to detect differences between the two clades. First, current methods for analysing species-level phylogenies may be sensitive to taxonomic and sampling artefacts. Second, lentic and lotic clades may indeed display similar levels of species turnover despite occupying very different habitats at different spatial scales. More work is needed to investigate the effects of population level processes and spatial scale on macroevolutionary dynamics.


Assuntos
Besouros/genética , Meio Ambiente , Evolução Molecular , Água Doce , Filogenia , Animais , Sequência de Bases , Besouros/enzimologia , Besouros/fisiologia , Simulação por Computador , DNA Mitocondrial/química , DNA Mitocondrial/isolamento & purificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Região do Mediterrâneo , Dados de Sequência Molecular , Método de Monte Carlo , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Análise de Sequência de DNA , Especificidade da Espécie
20.
An. med. interna (Madr., 1983) ; 21(3): 135-137, mar. 2004.
Artigo em Es | IBECS (Espanha) | ID: ibc-31131

RESUMO

La enfermedad de Kikuchi-Fujimoto o linfadenitis necrotizante histiocitaria es un proceso autolimitado del sistema linfático que afecta con más frecuencia a mujeres jóvenes. Clínicamente se caracteriza por la presencia de fiebre y de adenopatías, sobretodo cervicales. El diagnóstico se basa fundamentalmente en la biopsia del ganglio afectado, ya que a menudo los datos de laboratorio son normales. Es una enfermedad rara en España, siendo más frecuente en países orientales. Se trata de un proceso de evolución benigna, con resolución espontánea en semanas o meses, razón por la cual esta enfermedad podría estar infradiagnosticada. Es fundamental su distinción de los linfomas, dado que la enfermedad de Kikuchi no necesita tratamiento (AU)


No disponible


Assuntos
Masculino , Adulto , Humanos , Vírus da Caxumba , Caxumba , Linfonodos , Linfadenite Histiocítica Necrosante , Anticorpos Antivirais
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