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2.
NMR Biomed ; 31(5): e3901, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29457661

RESUMO

Measurements of hyperpolarized 13 C label exchange between injected [1-13 C]pyruvate and the endogenous tumor lactate pool can give an apparent first-order rate constant for the exchange. The determination of the isotope flux, however, requires an estimate of the labeled pyruvate concentration in the tumor. This was achieved here by measurement of the tumor uptake of [1-14 C]pyruvate, which showed that <2% of the injected pyruvate reached the tumor site. Multiplication of this estimated labeled pyruvate concentration in the tumor with the apparent first-order rate constant for hyperpolarized 13 C label exchange gave an isotope flux that showed good agreement with a flux determined directly by the injection of non-polarized [3-13 C]pyruvate, rapid excision of the tumor after 30 s and measurement of 13 C-labeled lactate concentrations in tumor extracts. The distribution of labeled lactate between intra- and extracellular compartments and the blood pool was investigated by imaging, by measurement of the labeled lactate concentration in blood and tumor, and by examination of the effects of a gadolinium contrast agent and a lactate transport inhibitor on the intensity of the hyperpolarized [1-13 C]lactate signal. These measurements showed that there was significant export of labeled lactate from the tumor, but that labeled lactate in the blood pool produced by the injection of hyperpolarized [1-13 C]pyruvate showed only relatively low levels of polarization. This study shows that measurements of hyperpolarized 13 C label exchange between pyruvate and lactate in a murine tumor model can provide an estimate of the true isotope flux if the concentration of labeled pyruvate that reaches the tumor can be determined.


Assuntos
Isótopos de Carbono/metabolismo , Radioisótopos de Carbono/metabolismo , Ácido Láctico/sangue , Linfoma/sangue , Ácido Pirúvico/sangue , Animais , Injeções , Marcação por Isótopo , Camundongos Endogâmicos C57BL , Distribuição Tecidual
3.
J Fish Biol ; 90(6): 2239-2254, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28369894

RESUMO

Larval development and allometric growth patterns of the black-faced blenny Tripterygion delaisi are described from a larval series (body length, LB = 3·30-12·10 mm) caught by light traps at the Arrábida Marine Park, Portugal. Larvae of T. delaisi possess distinctive morphometric and meristic characteristics which can be used to identify this species from related taxa. Pigmentation is sparse but characteristic, consisting of pigmented eyes, gas bladder pigmentation in the dorsal region, anal pigmentation and a row of regularly spaced postanal ventral melanophores. This pattern is present from as early as the yolk-sac stage and persists throughout all stages with just the addition of head and caudal pigmentation during the flexion and postflexion stages, respectively. The majority of fin development (with the exception of the caudal fin), occurs in the later stages of development. Myomere counts range between 37 and 45 for all stages. Growth is allometric during larval development. When inflexion points of growth were detected, growth was found to be biphasic with the inflexion points occurring within a very narrow range of LB (8·70-8·90 mm) close to the mean ± s.d. (9·44 ± 1·48 mm LB ) of postflexion larvae. Considering allometric growth patterns and ontogenetic descriptions together, the first developmental phase includes the preflexion and flexion stage larvae, while the second phase characterises the postflexion larvae prior to the transition from larvae to juvenile.


Assuntos
Peixes/crescimento & desenvolvimento , Nadadeiras de Animais/anatomia & histologia , Nadadeiras de Animais/crescimento & desenvolvimento , Animais , Peixes/anatomia & histologia , Larva/anatomia & histologia , Larva/crescimento & desenvolvimento , Pigmentação , Portugal
4.
Sci Rep ; 7: 44348, 2017 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-28276501

RESUMO

Global climate change is likely to constrain low latitude range edges across many taxa and habitats. Such is the case for NE Atlantic marine macroalgal forests, important ecosystems whose main structuring species is the annual kelp Saccorhiza polyschides. We coupled ecological niche modelling with simulations of potential dispersal and delayed development stages to infer the major forces shaping range edges and to predict their dynamics. Models indicated that the southern limit is set by high winter temperatures above the physiological tolerance of overwintering microscopic stages and reduced upwelling during recruitment. The best range predictions were achieved assuming low spatial dispersal (5 km) and delayed stages up to two years (temporal dispersal). Reconstructing distributions through time indicated losses of ~30% from 1986 to 2014, restricting S. polyschides to upwelling regions at the southern edge. Future predictions further restrict populations to a unique refugium in northwestern Iberia. Losses were dependent on the emissions scenario, with the most drastic one shifting ~38% of the current distribution by 2100. Such distributional changes might not be rescued by dispersal in space or time (as shown for the recent past) and are expected to drive major biodiversity loss and changes in ecosystem functioning.


Assuntos
Kelp/fisiologia , Modelos Estatísticos , Feófitas/fisiologia , Dispersão Vegetal/fisiologia , Oceano Atlântico , Biodiversidade , Mudança Climática , Ecossistema , Estações do Ano
5.
Mol Ecol ; 26(8): 2379-2391, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28133884

RESUMO

Successful prevention and mitigation of biological invasions requires retracing the initial steps of introduction, as well as understanding key elements enhancing the adaptability of invasive species. We studied the genetic diversity of the green alga Caulerpa taxifolia and its associated bacterial communities in several areas around the world. The striking congruence of α and ß diversity of the algal genome and endophytic communities reveals a tight association, supporting the holobiont concept as best describing the unit of spreading and invasion. Both genomic compartments support the hypotheses of a unique accidental introduction in the Mediterranean and of multiple invasion events in southern Australia. In addition to helping with tracing the origin of invasion, bacterial communities exhibit metabolic functions that can potentially enhance adaptability and competitiveness of the consortium they form with their host. We thus hypothesize that low genetic diversities of both host and symbiont communities may contribute to the recent regression in the Mediterranean, in contrast with the persistence of highly diverse assemblages in southern Australia. This study supports the importance of scaling up from the host to the holobiont for a comprehensive understanding of invasions.


Assuntos
Caulerpa/genética , Caulerpa/microbiologia , Variação Genética , Espécies Introduzidas , Microbiota , Simbiose , Bactérias/classificação , DNA Bacteriano/genética , Genética Populacional , Genótipo , Mar Mediterrâneo , Repetições de Microssatélites , RNA Ribossômico 16S/genética , Austrália do Sul
6.
Mar Environ Res ; 114: 12-23, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26741737

RESUMO

Marine protected areas (MPAs) are a relatively recent fisheries management and conservation tool for conservation of marine ecosystems and serve as experimental grounds to assess trophic cascade effects in areas were fishing is restricted to some extent. A series of descriptive field studies were performed to assess fish and benthic communities between two areas within a newly established MPA in SW Portugal. We characterized benthic macroalgal composition and determined the size, density and biomass of the main benthic predatory and herbivorous fish species as well as the main benthic herbivorous invertebrates to assess indications of top-down control on the phytobenthic assemblages. Fish species were identical inside and outside the MPA, in both cases Sarpa salpa was the most abundant fish herbivore and Diplodus spp. accounted for the great majority of the benthic predators. However, size and biomass of D. spp. were higher inside than outside the MPA. The main herbivorous invertebrate was the sea urchin Paracentrotus lividus, which was smaller and predominantly showing a crevice-dwelling behaviour in the MPA. In addition, P. lividus size frequency distribution showed a unimodal pattern outside and a bimodal pattern inside the MPA. We found significant differences in the algal assemblages between inside and outside the MPA, with higher abundance of turf and foliose algae inside, and articulated calcareous and corticated macrophytes outside the MPA, but no differences in the invasive Asparagopsis spp. The obtained results show differences in predatory fish and benthic community structure, but not in species richness, inside and outside the MPA. We hypothesize these differences lead to variation in species interactions: directly through predation and indirectly via affecting sea urchins behavioural patterns, predators might drive changes in macroalgal assemblages via trophic cascade in the study area. However due to non-biological differences between the two areas it is difficult to suggest that the MPA causes increased biological parameters of targeted species and to assess predatory control and trophic cascade effects in areas where fishing pressure is reduced. It is therefor advisable to design MPAs so that their impacts can be scientifically evaluated in a proper fashion.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Peixes/fisiologia , Invertebrados/fisiologia , Microalgas/fisiologia , Animais , Organismos Aquáticos , Cadeia Alimentar , Portugal
7.
Heredity (Edinb) ; 116(4): 378-83, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26758187

RESUMO

In salmonids, the release of hatchery-reared fish has been shown to cause irreversible genetic impacts on wild populations. However, although responsible practices for producing and releasing genetically diverse, hatchery-reared juveniles have been published widely, they are rarely implemented. Here, we investigated genetic differences between wild and early-generation hatchery-reared populations of the purple sea urchin Paracentrotus lividus (a commercially important species in Europe) to assess whether hatcheries were able to maintain natural levels of genetic diversity. To test the hypothesis that hatchery rearing would cause bottleneck effects (that is, a substantial reduction in genetic diversity and differentiation from wild populations), we compared the levels and patterns of genetic variation between two hatcheries and four nearby wild populations, using samples from both Spain and Ireland. We found that hatchery-reared populations were less diverse and had diverged significantly from the wild populations, with a very small effective population size and a high degree of relatedness between individuals. These results raise a number of concerns about the genetic impacts of their release into wild populations, particularly when such a degree of differentiation can occur in a single generation of hatchery rearing. Consequently, we suggest that caution should be taken when using hatchery-reared individuals to augment fisheries, even for marine species with high dispersal capacity, and we provide some recommendations to improve hatchery rearing and release practices. Our results further highlight the need to consider the genetic risks of releasing hatchery-reared juveniles into the wild during the establishment of restocking, stock enhancement and sea ranching programs.


Assuntos
Aquicultura , Conservação dos Recursos Naturais , Variação Genética , Genética Populacional , Ouriços-do-Mar/genética , Animais , Teorema de Bayes , Pesqueiros , Irlanda , Repetições de Microssatélites , Densidade Demográfica , Espanha
8.
Mar Genomics ; 23: 27-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25863290

RESUMO

The copepod Calanus glacialis plays a key role in the Arctic pelagic ecosystem. Despite its ecological importance and ongoing climate changes, limited knowledge at the genomic level has hindered the understanding of the molecular processes underlying environmental stress responses and ecological adaptation. Transcriptome data was generated from an experiment with C. glacialis copepodite (CV) subjected to five different temperatures. We obtained a total of 512,352 high-quality 454 pyrosequencing reads, which were assembled into 55,562 contigs distributed in 128 KEGG pathways. Functional analysis revealed numerous genes related to diverse biological functions and processes, including members of all major conserved signaling pathways. Comparative analysis of acclimated individuals to experimental temperatures has provided information about gene variations observed in several pathways (e.g. genes involved in energy, lipid and amino acid metabolism were shown to be down-regulated with increasing temperatures). These mRNA sequence resources will facilitate further studies on genomics and physiology-driven molecular processes in C. glacialis and related species.


Assuntos
Copépodes/genética , Regulação da Expressão Gênica/fisiologia , Temperatura Ambiente , Transcriptoma , Animais , Biologia Computacional
9.
Medicine (Baltimore) ; 94(3): e436, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25621698

RESUMO

This report describes an endovascular repair of a residual type A dissection using a medical device that is not marked by european conformity (CE) or Food and Drug Administration (FDA).The patient underwent ascending aortic surgery for acute type A dissection. The 2-year angio-computed tomography demonstrated patency of the residual false lumen with evolution into a 6 cm aneurysm, the extension of the dissection from the aortic arch to the aortic bifurcation with thrombosis of the right common iliac artery. There was no CE- or FDA-marked medical device indicated for this case or any other acceptable therapeutic alternative.We used the Najuta thoracic stent graft and successfully handled the pathology in a multiple-phase treatment.Technology is evolving with specific grafts for the ascending and fenestrated grafts for the aortic arch. In this single case the Najuta endograft, in spite of the periprocedural problems, was a valid therapeutic option.


Assuntos
Ruptura Aórtica/cirurgia , Aprovação de Equipamentos , Procedimentos Endovasculares/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Stents , Aprovação de Equipamentos/legislação & jurisprudência , Europa (Continente) , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Estados Unidos
10.
Mol Ecol ; 23(11): 2797-810, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24766057

RESUMO

The climate-driven dynamics of species ranges is a critical research question in evolutionary ecology. We ask whether present intraspecific diversity is determined by the imprint of past climate. This is an ongoing debate requiring interdisciplinary examination of population genetic pools and persistence patterns across global ranges. Previously, contrasting inferences and predictions have resulted from distinct genomic coverage and/or geographical information. We aim to describe and explain the causes of geographical contrasts in genetic diversity and their consequences for the future baseline of the global genetic pool, by comparing present geographical distribution of genetic diversity and differentiation with predictive species distribution modelling (SDM) during past extremes, present time and future climate scenarios for a brown alga, Fucus vesiculosus. SDM showed that both atmospheric and oceanic variables shape the global distribution of intertidal species, revealing regions of persistence, extinction and expansion during glacial and postglacial periods. These explained the distribution and structure of present genetic diversity, consisting of differentiated genetic pools with maximal diversity in areas of long-term persistence. Most of the present species range comprises postglacial expansion zones and, in contrast to highly dispersive marine organisms, expansions involved only local fronts, leaving distinct genetic pools at rear edges. Besides unravelling a complex phylogeographical history and showing congruence between genetic diversity and persistent distribution zones, supporting the hypothesis of niche conservatism, range shifts and loss of unique genetic diversity at the rear edge were predicted for future climate scenarios, impoverishing the global gene pool.


Assuntos
Clima , Fucus/genética , Pool Gênico , Variação Genética , Oceano Atlântico , Genética Populacional , Modelos Genéticos , Filogeografia , Dinâmica Populacional
11.
J Cardiovasc Surg (Torino) ; 55(2): 265-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24670833

RESUMO

We report an endovascular approach that used to treat a symptomatic extracranial vertebral artery aneurysm associated to an asymptomatic aberrant right subclavian artery aneurysm. A 54-year-old man presented with neck pain, vertigo and loss of balance. The computed tomography (CT) scan demonstrated a left extracranial vertebral artery aneurysm that compressed and eroded the C5 vertebra associated to an aberrant right subclavian artery aneurysm. Endovascular exclusion of the vertebral aneurysm using a covered stent and a hybrid treatment of the aberrant subclavian artery aneurysm were performed. The 13th month follow-up CT scan confirmed the stent-grafts and supra-aortic vessels patency. The endovascular treatment represents a good option for these complex pathologies with excellent immediate results, reduces the complication rate and the hospital stay if compared to open repair. Long-term follow-up is necessary. To our knowledge this is a unique case in the literature.


Assuntos
Aneurisma/cirurgia , Implante de Prótese Vascular , Anormalidades Cardiovasculares/cirurgia , Transtornos de Deglutição/cirurgia , Procedimentos Endovasculares , Artéria Subclávia/anormalidades , Artéria Vertebral/cirurgia , Aneurisma/diagnóstico por imagem , Prótese Vascular , Implante de Prótese Vascular/instrumentação , Anormalidades Cardiovasculares/diagnóstico por imagem , Transtornos de Deglutição/diagnóstico por imagem , Procedimentos Endovasculares/instrumentação , Humanos , Masculino , Pessoa de Meia-Idade , Stents , Artéria Subclávia/diagnóstico por imagem , Artéria Subclávia/cirurgia , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Artéria Vertebral/diagnóstico por imagem
12.
Genome ; 57(1): 57-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24564216

RESUMO

Ruppia cirrhosa is a clonal monoecious plant phylogenetically associated to seagrass families such as Posidoniaceae and Cymodoceaceae. It inhabits shallow waters that are important for productivity and as a biodiversity reservoir. In this study, we developed 10 polymorphic microsatellite loci for R. cirrhosa. Additionally, we obtained cross-amplification for two microsatellites previously described for Ruppia maritima. These 12 markers were tested in four R. cirrhosa populations from the southwest of Europe. The number of alleles per locus was high for most of the markers, ranging from 4 to 13. Two populations (Sicily and Cádiz) showed heterozygote deficit (p < 0.001). The four populations (Sicily, Murcia, Cádiz, and Tavira) were significantly differentiated (F(ST) ≠ 0; p < 0.001), corroborating the usefulness of these microsatellites on R. cirrhosa population genetics.


Assuntos
Alismatales/classificação , Alismatales/genética , Repetições de Microssatélites , Folhas de Planta/genética , Alelos , Biodiversidade , Europa (Continente) , Evolução Molecular , Marcadores Genéticos , Variação Genética , Genética Populacional , Genoma de Planta , Filogenia
13.
J Cardiovasc Surg (Torino) ; 54(5): 581-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24002387

RESUMO

AIM: Aim of the study was to report our single-center experience of the ultra-low profile OvationTM Abdominal Stent-Graft System with totally percutaneous endovascular aneurysm repair (PEVAR). METHODS: Between December 2010 and March 2013 we electively treated 35 patients (male: 89%, mean age: 73±7 years) with abdominal aortic aneurysm (AAA) using bilateral PEVAR with the OvationTM endograft. Most (77%) cases were characterized by challenging femoral artery anatomy. Patients returned for follow-up visits at 1, 3, 6 months and annually thereafter. RESULTS: Technical success was 97.1%. One type Ia endoleak was identified on final angiography, which was treated with an extension cuff. No groin complications were observed, including lymphocele, hematoma, pseudoaneurysm, dehiscence, or wound infection. Mean follow-up was 10 months (range 1-24 months). No death was registered. One type Ia endoleak was identified at the 12-month follow-up, which resolved with placement of a Palmaz balloon-expandible stent. No type II, III, or IV endoleaks were identified. No migration, AAA enlargement, AAA rupture, or conversion to open surgery was reported. Two patients (5.7%) developed monolateral iliac limb occlusion at 58 and 72 days of follow-up, respectively. In one case a limb kinking was observed and treated with iliac kissing stent. The other limb occlusion was due to external iliac artery severe stenosis and was treated with thrombolysis and iliac artery stenting. CONCLUSION: PEVAR with the OvationTM endograft is feasible and safe in patients with unfavorable anatomy.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Procedimentos Endovasculares/instrumentação , Stents , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aortografia/métodos , Implante de Prótese Vascular/efeitos adversos , Endoleak/etiologia , Endoleak/terapia , Procedimentos Endovasculares/efeitos adversos , Feminino , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Estudos Retrospectivos , Fatores de Tempo , Tomografia Computadorizada Espiral , Resultado do Tratamento
14.
Eur J Vasc Endovasc Surg ; 45(5): 475-80, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23465453

RESUMO

BACKGROUND: Open repair is the gold standard for type A aortic dissection (TAAD). Endovascular option has been proposed in very limited and selected TAAD patients. We report our experience with endovascular TAAD repair. METHODS: Inclusion criteria were: (1) entry tear in the ascending aorta; (2) proximal landing zone of at least 2 cm; (3) distance between entry tear and brachio-cephalic trunk of at least 0.5 cm; (4) no signs of cardiac tamponade or severe aortic regurgitation and (5) no signs of aortic branches ischaemia. Patients with cardiac revascularisation from ascending aorta were excluded. RESULTS: From April 2009 to June 2012, 37 patients with TAAD were admitted to our hospital. As many as 28 underwent surgical repair and 9 were considered at high surgical risk in a multidisciplinary meeting. Four met our inclusion criteria for an endovascular approach. Two of them had previous ascending aortic repair for TAAD and one had aortic valve replacement. Technical success was achieved in 100% of the patients. No mortality was registered during a median follow-up of 15 months (range 4-39 months), no migration of the graft and complete false lumen thrombosis of the ascending aorta in three patients. CONCLUSION: Endovascular treatment of TAAD is challenging but feasible in a selected subset of patients. Further research remains mandatory.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Conversão para Cirurgia Aberta/estatística & dados numéricos , Procedimentos Endovasculares , Stents , Idoso , Aorta , Aneurisma da Aorta Torácica/classificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
15.
Mol Phylogenet Evol ; 58(2): 283-96, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21111835

RESUMO

We examined 733 individuals of Fucusspiralis from 21 locations and 1093 Fucusvesiculosus individuals from 37 locations throughout their northern hemisphere ranges using nuclear and mitochondrial markers. Three genetic entities of F. spiralis were recovered. In northern and sympatric populations, the presence of "F. spiralis Low" in the mid-intertidal and "F. spiralis High" in the high-intertidal was confirmed and both co-occurred with the sister species F. vesiculosus. The third and newly-discovered entity, "F. spiralis South", was present mainly in the southern range, where it did not co-occur with F. vesiculosus. The South entity diverged early in allopatry, then hybridized with F. vesiculosus in sympatry to produce F. spiralis Low. Ongoing parallel evolution of F. spiralis Low and F. spiralis High is most likely due to habitat preference/local selection and maintained by preferentially selfing reproductive strategies. Contemporary populations of F. spiralis throughout the North Atlantic stem from a glacial refugium around Brittany involving F. spiralis High; F. spiralis South was probably unaffected by glacial episodes. Exponential population expansion for F. vesiculosus began during the Cromer and/Holstein interglacial period (300,000-200,000 yrs BP). Following the last glacial maximum (30,000-22,000 yrs BP), a single mtDNA haplotype from a glacial refugium in SW Ireland colonized Scandinavia, the Central Atlantic islands, and the W Atlantic.


Assuntos
Evolução Molecular , Fucus/genética , Genética Populacional , Oceano Atlântico , Núcleo Celular/genética , DNA Mitocondrial/genética , Ecossistema , Haplótipos , Repetições de Microssatélites , Polimorfismo Conformacional de Fita Simples , Análise de Sequência de DNA
16.
Minerva Chir ; 65(1): 11-5, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20212412

RESUMO

AIM: Recently the NOTES approach has been extended to mediastinum by a transesophageal access and to the thorax by a transvescical endoscopic approach. The aim of this study was to assess the feasibility and the safety of transgastric endoscopic approach to the thoracic cavity, with lung biopsy, in a survival porcine model. METHODS: The study was performed on four 20-30 kg female pigs (Sus scrofus domesticus). Following gastric wall incision, the muscular pars of the left diaphragmatic dome was incised along with the parietal pleura and the endoscope advanced into the thoracic cavity. In all animals, a thoracoscopy was performed as well as peripheral lung biopsy. At the end of the operation the endoscope was withdrawn from the thoracic cavity after pleural sac decompression and the diaphragmatic incision closed by endoscopic clips under maximal expansion of lungs. The gastric incision was finally closed by endoscopic clips. Chest-tube placement was not utilized. Animals were sacrificed by day 15 postoperatively. RESULTS: The gastroscope was easily introduced into the thoracic cavity that allowed to visualize the pleural cavity and to perform simple surgical procedures such as lung biopsies without complications. There were neither respiratory distress episodes nor surgical complications to report. No adverse event occurred during the survival period. The postmortem examination 15 days after surgery revealed a good closure of the diaphragmatic incision. At necropsy, the lung biopsies were completely healed. There were no signs of infection in both thoracic and peritoneal cavities. The length of follow-up and number of animals studied might have not been sufficient. CONCLUSION: This study demonstrates the feasibility of transgastric thoracoscopy in porcine model. Long-term follow-up of much larger series will be necessary for provision of more reliable answers if this approach should be adopted in the future and eventually translated for humans with advantages for patients.


Assuntos
Toracoscopia/métodos , Animais , Diafragma/cirurgia , Estudos de Viabilidade , Feminino , Modelos Animais , Estômago , Suínos
17.
Mol Ecol ; 19(3): 557-68, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20051010

RESUMO

The Mediterranean Sea is a two-basin system, with the boundary zone restricted to the Strait of Sicily and the narrow Strait of Messina. Two main population groups are recognized in the Mediterranean endemic seagrass Posidonia oceanica, corresponding to the Western and the Eastern basins. To address the nature of the East-West cleavage in P. oceanica, the main aims of this study were: (i) to define the genetic structure within the potential contact zone (i.e. the Strait of Sicily) and clarify the extent of gene flow between the two population groups, and (ii) to investigate the role of present water circulation patterns vs. past evolutionary events on the observed genetic pattern. To achieve these goals, we utilized SSR markers and we simulated, with respect to current regime, the possible present-day dispersal pattern of Posidonia floating fruits using 28-day numerical Lagrangian trajectories. The results obtained confirm the presence of the two main population groups, without any indices of reproductive isolation, with the break zone located at the level of the Southern tip of Calabria. The populations in the Strait of Sicily showed higher affinity with Western than with Eastern populations. This pattern of genetic structure probably reflects historical avenues of recolonization from relict glacial areas and past vicariance events, but seems to persist as a result of the low connectivity among populations via marine currents, as suggested by our dispersal simulation analysis.


Assuntos
Alismatales/genética , Fluxo Gênico , Genética Populacional , Simulação por Computador , DNA de Plantas/genética , Evolução Molecular , Genótipo , Geografia , Mar Mediterrâneo , Repetições de Microssatélites , Polimorfismo Genético , Análise de Componente Principal , Análise de Sequência de DNA , Movimentos da Água
18.
J Cardiovasc Surg (Torino) ; 50(2): 189-93, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19329915

RESUMO

AIM: The aim of this study was to evaluate the usefulness of the temporal approach during coronary artery stenosis (CAS) to overcome tortuosity in case of difficult arch anatomy or tortuous common carotid artery, and to provide cerebral protection of proximal lesions of the supra-aortic trunks during stenting. METHODS: The superficial temporal artery is exposed through a small incision right in front of the ear and is cannulated. A guidewire is used to descend in the external and common carotid artery and in the arch if needed. Between the end of March 2007 and May 2008 9 patients were treated with the temporal approach: in 5 cases of stenosis of the internal carotid artery with difficult arch anatomy to obtain a through and through guide from the temporal to the femoral artery, in 3 of the supra-aortic trunks to obtain cerebral protection during the procedure and in one case of tandem lesion of the left common and internal carotid artery. RESULTS: The procedure was successful in all 9 cases and there were no complications. CONCLUSIONS: The temporal approach proved to be feasible and at low risk; it represents a new possibility to increase the feasibility of carotid artery stenting in patients with difficult anatomy but, above all, it is a good way to obtain cerebral protection during endovascular treatment of proximal lesions of the supra-aortic vessels.


Assuntos
Angioplastia com Balão/métodos , Estenose das Carótidas/terapia , Cateterismo Periférico , Acidente Vascular Cerebral/prevenção & controle , Artérias Temporais , Idoso , Idoso de 80 Anos ou mais , Angioplastia com Balão/efeitos adversos , Angioplastia com Balão/instrumentação , Estenose das Carótidas/diagnóstico por imagem , Cateterismo Periférico/efeitos adversos , Estudos de Viabilidade , Feminino , Humanos , Masculino , Radiografia , Stents , Acidente Vascular Cerebral/etiologia , Resultado do Tratamento
19.
Mol Ecol ; 16(24): 5115-39, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17944846

RESUMO

Although clonal species are dominant in many habitats, from unicellular organisms to plants and animals, ecological and particularly evolutionary studies on clonal species have been strongly limited by the difficulty in assessing the number, size and longevity of genetic individuals within a population. The development of molecular markers has allowed progress in this area, and although allozymes remain of limited use due to their typically low level of polymorphism, more polymorphic markers have been discovered during the last decades, supplying powerful tools to overcome the problem of clonality assessment. However, population genetics studies on clonal organisms lack a standardized framework to assess clonality, and to adapt conventional data analyses to account for the potential bias due to the possible replication of the same individuals in the sampling. Moreover, existing studies used a variety of indices to describe clonal diversity and structure such that comparison among studies is difficult at best. We emphasize the need for standardizing studies on clonal organisms, and particularly on clonal plants, in order to clarify the way clonality is taken into account in sampling designs and data analysis, and to allow further comparison of results reported in distinct studies. In order to provide a first step towards a standardized framework to address clonality in population studies, we review, on the basis of a thorough revision of the literature on population structure of clonal plants and of a complementary revision on other clonal organisms, the indices and statistics used so far to estimate genotypic or clonal diversity and to describe clonal structure in plants. We examine their advantages and weaknesses as well as various conceptual issues associated with statistical analyses of population genetics data on clonal organisms. We do so by testing them on results from simulations, as well as on two empirical data sets of microsatellites of the seagrasses Posidonia oceanica and Cymodocea nodosa. Finally, we also propose a selection of new indices and methods to estimate clonal diversity and describe clonal structure in a way that should facilitate comparison between future studies on clonal plants, most of which may be of interest for clonal organisms in general.


Assuntos
Genética Populacional/métodos , Genética Populacional/normas , Biomarcadores , Genética Populacional/classificação , Genótipo , Plantas/genética , Dinâmica Populacional , Software
20.
Mol Ecol ; 15(12): 3515-25, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17032254

RESUMO

Understanding the genetic composition and mating systems of edge populations provides important insights into the environmental and demographic factors shaping species' distribution ranges. We analysed samples of the mangrove Avicennia marina from Vietnam, northern Philippines and Australia, with microsatellite markers. We compared genetic diversity and structure in edge (Southeast Asia, and Southern Australia) and core (North and Eastern Australia) populations, and also compared our results with previously published data from core and southern edge populations. Comparisons highlighted significantly reduced gene diversity and higher genetic structure in both margins compared to core populations, which can be attributed to very low effective population size, pollinator scarcity and high environmental pressure at distribution margins. The estimated level of inbreeding was significantly higher in northeastern populations compared to core and southern populations. This suggests that despite the high genetic load usually associated with inbreeding, inbreeding or even selfing may be advantageous in margin habitats due to the possible advantages of reproductive assurance, or local adaptation. The very high level of genetic structure and inbreeding show that populations of A. marina are functioning as independent evolutionary units more than as components of a metapopulation system connected by gene flow. The combinations of those characteristics make these peripheral populations likely to develop local adaptations and therefore to be of particular interest for conservation strategies as well as for adaptation to possible future environmental changes.


Assuntos
Avicennia/genética , Biodiversidade , Endogamia , Austrália , Avicennia/fisiologia , Fluxo Gênico , Variação Genética , Geografia , Desequilíbrio de Ligação , Repetições de Microssatélites , Filipinas , Vietnã
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