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1.
Mol Phylogenet Evol ; 194: 108022, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38325534

RESUMEN

The world's largest butterfly genus Delias, commonly known as Jezebels, comprises ca. 251 species found throughout Asia, Australia, and Melanesia. Most species are endemic to islands in the Indo-Australian Archipelago or to New Guinea and nearby islands in Melanesia, and many species are restricted to montane habitats over 1200 m. We inferred an extensively sampled and well-supported molecular phylogeny of the group to better understand the spatial and temporal dimensions of its diversification. The remarkable diversity of Delias evolved in just ca. 15-16 Myr (crown age). The most recent common ancestor of a clade with most of the species dispersed out of New Guinea ca. 14 Mya, but at least six subsequently diverging lineages dispersed back to the island. Diversification was associated with frequent dispersal of lineages among the islands of the Indo-Australian Archipelago, and the divergence of sister taxa on a single landmass was rare and occurred only on the largest islands, most notably on New Guinea. We conclude that frequent inter-island dispersal during the Neogene-likely facilitated by frequent sea level change-sparked much diversification during that period. Many extant New Guinea lineages started diversifying 5 Mya, suggesting that orogeny facilitated their diversification. Our results largely agree with the most recently proposed species group classification system, and we use our large taxon sample to extend this system to all described species. Finally, we summarize recent insights to speculate how wing pattern evolution, mimicry, and sexual selection might also contribute to these butterflies' rapid speciation and diversification.


Asunto(s)
Mariposas Diurnas , Animales , Filogenia , Mariposas Diurnas/genética , Nueva Guinea , Australia , Ecosistema
2.
Pancreatology ; 24(3): 363-369, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38431445

RESUMEN

OBJECTIVE: Hemin, a heme oxygenase 1 activator has shown efficacy in the prevention and treatment of acute pancreatitis in mouse models. We conducted a randomized controlled trial (RCT) to assess the protective effect of Hemin administration to prevent post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) in patients at risk. METHODS: In this multicenter, multinational, placebo-controlled, double-blind RCT, we assigned patients at risk for PEP to receive a single intravenous dose of Hemin (4 mg/kg) or placebo immediately after ERCP. Patients were considered to be at risk on the basis of validated patient- and/or procedure-related risk factors. Neither rectal NSAIDs nor pancreatic stent insertion were allowed in randomized patients. The primary outcome was the incidence of PEP. Secondary outcomes included lipase elevation, mortality, safety, and length of stay. RESULTS: A total of 282 of the 294 randomized patients had complete follow-up. Groups were similar in terms of clinical, laboratory, and technical risk factors for PEP. PEP occurred in 16 of 142 patients (11.3%) in the Hemin group and in 20 of 140 patients (14.3%) in the placebo group (p = 0.48). Incidence of severe PEP reached 0.7% and 4.3% in the Hemin and placebo groups, respectively (p = 0.07). Significant lipase elevation after ERCP did not differ between groups. Length of hospital stay, mortality and severe adverse events rates were similar between groups. CONCLUSION: We failed to detect large improvements in PEP rate among participants at risk for PEP who received IV hemin immediately after the procedure compared to placebo. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov number, NCT01855841).


Asunto(s)
Colangiopancreatografia Retrógrada Endoscópica , Pancreatitis , Animales , Humanos , Ratones , Antiinflamatorios no Esteroideos/uso terapéutico , Colangiopancreatografia Retrógrada Endoscópica/efectos adversos , Hemo-Oxigenasa 1 , Hemina/uso terapéutico , Lipasa , Pancreatitis/etiología , Pancreatitis/prevención & control , Administración Intravenosa
3.
Mol Phylogenet Evol ; 183: 107758, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36907224

RESUMEN

The swallowtail genus Papilio (Lepidoptera: Papilionidae) is species rich, distributed worldwide, and has broad morphological habits and ecological niches. Because of its elevated species richness, it has been historically difficult to reconstruct a densely sampled phylogeny for this clade. Here we provide a taxonomic working list for the genus, resulting in 235 Papilio species, and assemble a molecular dataset of seven gene fragments representing ca. 80% of the currently described diversity. Phylogenetic analyses reconstructed a robust tree with highly supported relationships within subgenera, although a few nodes in the early history of the Old World Papilio remain unresolved. Contrasting with previous results, we found that Papilio alexanor is sister to all Old World Papilio and that the subgenus Eleppone is no longer monotypic. The latter includes the recently described Fijian Papilio natewa with the Australian Papilio anactus and is sister to subgenus Araminta (formerly included in subgenus Menelaides) occurring in Southeast Asia. Our phylogeny also includes rarely studied (P. antimachus, P. benguetana) or endangered species (P. buddha, P. chikae). Taxonomic changes resulting from this study are elucidated. Molecular dating and biogeographic analyses indicate that Papilio originated ca. 30 million years ago (Oligocene), in a northern region centered on Beringia. A rapid early Miocene radiation in the Paleotropics is revealed within Old World Papilio, potentially explaining their low early branch support. Most subgenera originated in the early to middle Miocene followed by synchronous southward biogeographic dispersals and repeated local extirpations in northern latitudes. This study provides a comprehensive phylogenetic framework for Papilio with clarification of subgeneric systematics and species taxonomic changes enumerated, which will facilitate further studies to address questions on their ecology and evolutionary biology using this model clade.


Asunto(s)
Mariposas Diurnas , Animales , Filogenia , Australia , Mariposas Diurnas/genética , Evolución Biológica , Asia Sudoriental
4.
Syst Biol ; 70(3): 413-420, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-32882028

RESUMEN

Understanding the evolutionary mechanisms governing the uneven distribution of species richness across the tree of life is a great challenge in biology. Scientists have long argued that sexual conflict is a key driver of speciation. This hypothesis, however, has been highly debated in light of empirical evidence. Recent advances in the study of macroevolution make it possible to test this hypothesis with more data and increased accuracy. In the present study, we use phylogenomics combined with four different diversification rate analytical approaches to test whether sexual conflict is a driver of speciation in brush-footed butterflies of the tribe Acraeini. The presence of a sphragis, an external mating plug found in most species among Acraeini, was used as a proxy for sexual conflict. Diversification analyses statistically rejected the hypothesis that sexual conflict is associated with shifts in diversification rates in Acraeini. This result contrasts with earlier studies and suggests that the underlying mechanisms driving diversification are more complex than previously considered. In the case of butterflies, natural history traits acting in concert with abiotic factors possibly play a stronger role in triggering speciation than does sexual conflict. [Acraeini butterflies; arms race; exon capture phylogenomics; Lepidoptera macroevolution; sexual selection; sphragis.].


Asunto(s)
Mariposas Diurnas , Animales , Evolución Biológica , Mariposas Diurnas/genética , Especiación Genética , Fenotipo , Filogenia , Reproducción
5.
Proc Natl Acad Sci U S A ; 116(45): 22657-22663, 2019 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-31636187

RESUMEN

Butterflies and moths (Lepidoptera) are one of the major superradiations of insects, comprising nearly 160,000 described extant species. As herbivores, pollinators, and prey, Lepidoptera play a fundamental role in almost every terrestrial ecosystem. Lepidoptera are also indicators of environmental change and serve as models for research on mimicry and genetics. They have been central to the development of coevolutionary hypotheses, such as butterflies with flowering plants and moths' evolutionary arms race with echolocating bats. However, these hypotheses have not been rigorously tested, because a robust lepidopteran phylogeny and timing of evolutionary novelties are lacking. To address these issues, we inferred a comprehensive phylogeny of Lepidoptera, using the largest dataset assembled for the order (2,098 orthologous protein-coding genes from transcriptomes of 186 species, representing nearly all superfamilies), and dated it with carefully evaluated synapomorphy-based fossils. The oldest members of the Lepidoptera crown group appeared in the Late Carboniferous (∼300 Ma) and fed on nonvascular land plants. Lepidoptera evolved the tube-like proboscis in the Middle Triassic (∼241 Ma), which allowed them to acquire nectar from flowering plants. This morphological innovation, along with other traits, likely promoted the extraordinary diversification of superfamily-level lepidopteran crown groups. The ancestor of butterflies was likely nocturnal, and our results indicate that butterflies became day-flying in the Late Cretaceous (∼98 Ma). Moth hearing organs arose multiple times before the evolutionary arms race between moths and bats, perhaps initially detecting a wide range of sound frequencies before being co-opted to specifically detect bat sonar. Our study provides an essential framework for future comparative studies on butterfly and moth evolution.


Asunto(s)
Mariposas Diurnas/genética , Evolución Molecular , Mariposas Nocturnas/genética , Filogenia , Animales , Mariposas Diurnas/clasificación , Mariposas Diurnas/fisiología , Mariposas Nocturnas/clasificación , Mariposas Nocturnas/fisiología
6.
Mol Phylogenet Evol ; 137: 86-103, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31022515

RESUMEN

Our understanding of the origin and evolution of the astonishing Neotropical biodiversity remains somewhat limited. In particular, decoupling the respective impacts of biotic and abiotic factors on the macroevolution of clades is paramount to understand biodiversity assemblage in this region. We present the first comprehensive molecular phylogeny for the Neotropical Anaeini leafwing butterflies (Nymphalidae, Charaxinae) and, applying likelihood-based methods, we test the impact of major abiotic (Andean orogeny, Central American highland orogeny, Proto-Caribbean seaway closure, Quaternary glaciations) and biotic (host plant association) factors on their macroevolution. We infer a robust phylogenetic hypothesis for the tribe despite moderate support in some derived clades. Our phylogenetic inference recovers the genus Polygrapha Staudinger, [1887] as polyphyletic, rendering the genera FountaineaRydon, 1971 and Memphis Hübner, [1819] paraphyletic. Consequently, we transfer Polygrapha tyrianthina (Salvin & Godman, 1868) comb. nov. to Fountainea and Polygrapha xenocrates (Westwood, 1850) comb. nov. to Memphis. We infer an origin of the group in the late Eocene ca. 40 million years ago in Central American lowlands which at the time were separated from South America by the Proto-Caribbean seaway. The biogeographical history of the group is very dynamic, with several oversea colonization events from Central America into the Chocó and Andean regions during intense stages of Andean orogeny. These events coincide with the emergence of an archipelagic setting between Central America and northern South America in the mid-Miocene that likely facilitated dispersal across the now-vanished Proto-Caribbean seaway. The Amazonian region also played a central role in the diversification of the Anaeini, acting both as a museum and a cradle of diversity. We recover a diversification rate shift in the Miocene within the species-rich genus Memphis. State speciation and extinction models recover a significant relationship between this rate shift and host plant association, indicating a positive role on speciation rates of a switch between Malpighiales and new plant orders. We find less support for a role of abiotic factors including the progressive Andean orogeny, Proto-Caribbean seaway closure and Quaternary glaciations. Miocene host plant shifts possibly acted in concert with abiotic and/or biotic factors to shape the diversification of Anaeini butterflies.


Asunto(s)
Mariposas Diurnas/clasificación , Vuelo Animal/fisiología , Océanos y Mares , Filogenia , Clima Tropical , Alas de Animales/fisiología , Animales , Biodiversidad , Región del Caribe , Especiación Genética , Funciones de Verosimilitud , Filogeografía , Factores de Tiempo
7.
BMC Evol Biol ; 18(1): 101, 2018 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-29921227

RESUMEN

BACKGROUND: Butterflies (Papilionoidea) are perhaps the most charismatic insect lineage, yet phylogenetic relationships among them remain incompletely studied and controversial. This is especially true for skippers (Hesperiidae), one of the most species-rich and poorly studied butterfly families. METHODS: To infer a robust phylogenomic hypothesis for Hesperiidae, we sequenced nearly 400 loci using Anchored Hybrid Enrichment and sampled all tribes and more than 120 genera of skippers. Molecular datasets were analyzed using maximum-likelihood, parsimony and coalescent multi-species phylogenetic methods. RESULTS: All analyses converged on a novel, robust phylogenetic hypothesis for skippers. Different optimality criteria and methodologies recovered almost identical phylogenetic trees with strong nodal support at nearly all nodes and all taxonomic levels. Our results support Coeliadinae as the sister group to the remaining skippers, the monotypic Euschemoninae as the sister group to all other subfamilies but Coeliadinae, and the monophyly of Eudaminae plus Pyrginae. Within Pyrginae, Celaenorrhinini and Tagiadini are sister groups, the Neotropical firetips, Pyrrhopygini, are sister to all other tribes but Celaenorrhinini and Tagiadini. Achlyodini is recovered as the sister group to Carcharodini, and Erynnini as sister group to Pyrgini. Within the grass skippers (Hesperiinae), there is strong support for the monophyly of Aeromachini plus remaining Hesperiinae. The giant skippers (Agathymus and Megathymus) once classified as a subfamily, are recovered as monophyletic with strong support, but are deeply nested within Hesperiinae. CONCLUSIONS: Anchored Hybrid Enrichment sequencing resulted in a large amount of data that built the foundation for a new, robust evolutionary tree of skippers. The newly inferred phylogenetic tree resolves long-standing systematic issues and changes our understanding of the skipper tree of life. These resultsenhance understanding of the evolution of one of the most species-rich butterfly families.


Asunto(s)
Mariposas Diurnas/clasificación , Genómica , Filogenia , Animales , Secuencia de Bases , Mariposas Diurnas/genética , Funciones de Verosimilitud , Especificidad de la Especie
8.
Proc Biol Sci ; 285(1885)2018 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-30158307

RESUMEN

The origins and evolution of Hawaiian biodiversity are a matter of controversy, and the mechanisms of lineage diversification for many organisms on this remote archipelago remain unclear. Here we focus on the poorly known endemic leaf-mining moth genus Philodoria (Lepidoptera, Gracillariidae), whose species feed on a diversity of Hawaiian plant lineages, many of which are critically endangered. We use anchored hybrid enrichment to assemble the first phylogenomic dataset (507 loci) for any Hawaiian animal taxon. To uncover the timing and pattern of diversification of these moths, we apply two frequently used dating calibration strategies, biogeographic calibrations and secondary calibrations. Island calibrations on their own resulted in much younger and unrealistic dates compared to strategies that relied on secondary calibrations. Philodoria probably originated on the now partially sunken islands of Laysan or Lisianski, approximately 21 Ma, and were associated with host plants in the families Ebenaceae, Malvaceae or Primulaceae. Major feeding groups associated with specific host-plant families originated soon after the plants colonized the islands. Allopatric isolation and host shifts, in concert and independently, probably play major roles in the diversification of Philodoria Our dating results indicate that Philodoria is among the oldest known Hawaiian arthropod lineages, and that island calibrations alone can lead to unrealistically young dates.


Asunto(s)
Evolución Biológica , Mariposas Nocturnas/genética , Animales , Especiación Genética , Hawaii , Islas , Larva/genética , Mariposas Nocturnas/crecimiento & desarrollo , Filogenia
9.
Mol Ecol ; 27(17): 3541-3554, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30030868

RESUMEN

Recent theoretical advances have hypothesized a central role of habitat persistence on population genetic structure and resulting biodiversity patterns of freshwater organisms. Here, we address the hypothesis that lotic species, or lineages adapted to comparably geologically stable running water habitats (streams and their marginal habitats), have high levels of endemicity and phylogeographic structure due to the persistent nature of their habitat. We use a nextRAD DNA sequencing approach to investigate the population structure and phylogeography of a putatively widespread New Guinean species of diving beetle, Philaccolilus ameliae (Dytiscidae). We find that P. ameliae is a complex of morphologically cryptic, but geographically and genetically well-differentiated clades. The pattern of population connectivity is consistent with theoretical predictions associated with stable lotic habitats. However, in two clades, we find a more complex pattern of low population differentiation, revealing dispersal across rugged mountains and watersheds of New Guinea up to 430 km apart. These results, while surprising, were also consistent with the original formulation of the habitat template concept by Southwood, involving lineage-idiosyncratic evolution in response to abiotic factors. In our system, low population differentiation might reflect a young species in a phase of range expansion utilizing vast available habitat. We suggest that predictions of life history variation resulting from the dichotomy between lotic and lentic organisms require more attention to habitat characterization and microhabitat choice. Our results also underpin the necessity to study fine-scale processes but at a larger geographical scale, as compared to solely documenting macroecological patterns, to understand ecological drivers of regional biodiversity. Comprehensive sampling especially of tropical lineages in complex and threatened environments such as New Guinea remains a critical challenge.


Asunto(s)
Escarabajos/clasificación , Ecosistema , Genética de Población , Movimientos del Agua , Animales , Biodiversidad , Nueva Guinea , Filogenia , Filogeografía , Ríos , Clima Tropical
10.
Mol Phylogenet Evol ; 127: 416-428, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29747009

RESUMEN

Beetles have colonized freshwater habitats multiple times throughout their evolutionary history. Some of these aquatic lineages are associated exclusively with waterfall-like habitats, often with modified morphologies to cope with their unusual way of life. The historical biogeography of such cascade beetle lineages has been shown to strongly reflect ancient tectonic events. We focus on the pantropical genus Oocyclus of which species dwell in waterfalls and associated habitats. We infer the first molecular phylogeny of Oocyclus using a dataset of seven gene fragments. We recover a well resolved phylogenetic hypothesis, with a monophyletic Oocyclus divided in three genetically well-differentiated subclades which correspond to geography. Comparative dating analyses across Hydrophilidae based on ten fossil calibrations recover a Cretaceous origin for the genus. Based on a comprehensive suite of ancestral range analyses, we suggest a unique pattern with an origin in Southeast Asia followed by the successive colonization of India and the Neotropics via transoceanic stepping-stone dispersal. Diversification rate analyses support a scenario in which old Oocyclus lineages diversified slowly with a homogeneous rate regime. Waterfall beetle radiations are ancient and remarkably track Earth's paleogeological history, shedding light on intricate patterns of macroevolution.


Asunto(s)
Escarabajos/clasificación , Filogeografía , Clima Tropical , Animales , Teorema de Bayes , Ecosistema , Fósiles , Variación Genética , Filogenia , Factores de Tiempo
11.
Mol Phylogenet Evol ; 127: 600-605, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29902572

RESUMEN

The Neotropical moth-like butterflies (Hedylidae) are perhaps the most unusual butterfly family. In addition to being species-poor, this family is predominantly nocturnal and has anti-bat ultrasound hearing organs. Evolutionary relationships among the 36 described species are largely unexplored. A new, target capture, anchored hybrid enrichment probe set ('BUTTERFLY2.0') was developed to infer relationships of hedylids and some of their butterfly relatives. The probe set includes 13 genes that have historically been used in butterfly phylogenetics. Our dataset comprised of up to 10,898 aligned base pairs from 22 hedylid species and 19 outgroups. Eleven of the thirteen loci were successfully captured from all samples, and the remaining loci were captured from ≥94% of samples. The inferred phylogeny was consistent with recent molecular studies by placing Hedylidae sister to Hesperiidae, and the tree had robust support for 80% of nodes. Our results are also consistent with morphological studies, with Macrosoma tipulata as the sister species to all remaining hedylids, followed by M. semiermis sister to the remaining species in the genus. We tested the hypothesis that nocturnality evolved once from diurnality in Hedylidae, and demonstrate that the ancestral condition was likely diurnal, with a shift to nocturnality early in the diversification of this family. The BUTTERFLY2.0 probe set includes standard butterfly phylogenetics markers, captures sequences from decades-old museum specimens, and is a cost-effective technique to infer phylogenetic relationships of the butterfly tree of life.


Asunto(s)
Mariposas Diurnas/clasificación , Sondas de ADN/genética , Sitios Genéticos , Mariposas Nocturnas/clasificación , Filogenia , Animales , Secuencia de Bases , Funciones de Verosimilitud , Mariposas Nocturnas/genética
12.
Mol Phylogenet Evol ; 107: 282-292, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27789326

RESUMEN

The first molecular phylogenetic hypothesis for the aquatic beetle family Noteridae is inferred using DNA sequence data from five gene fragments (mitochondrial and nuclear): COI, H3, 16S, 18S, and 28S. Our analysis is the most comprehensive phylogenetic reconstruction of Noteridae to date, and includes 53 species representing all subfamilies, tribes and 16 of the 17 genera within the family. We examine the impact of data partitioning on phylogenetic inference by comparing two different algorithm-based partitioning strategies: one using predefined subsets of the dataset, and another recently introduced method, which uses the k-means algorithm to iteratively divide the dataset into clusters of sites evolving at similar rates across sampled loci. We conducted both maximum likelihood and Bayesian inference analyses using these different partitioning schemes. Resulting trees are strongly incongruent with prior classifications of Noteridae. We recover variant tree topologies and support values among the implemented partitioning schemes. Bayes factors calculated with marginal likelihoods of Bayesian analyses support a priori partitioning over k-means and unpartitioned data strategies. Our study substantiates the importance of data partitioning in phylogenetic inference, and underscores the use of comparative analyses to determine optimal analytical strategies. Our analyses recover Noterini Thomson to be paraphyletic with respect to three other tribes. The genera Suphisellus Crotch and Hydrocanthus Say are also recovered as paraphyletic. Following the results of the preferred partitioning scheme, we here propose a revised classification of Noteridae, comprising two subfamilies, three tribes and 18 genera. The following taxonomic changes are made: Notomicrinae sensu n. (= Phreatodytinae syn. n.) is expanded to include the tribe Phreatodytini; Noterini sensu n. (= Neohydrocoptini syn. n., Pronoterini syn. n., Tonerini syn. n.) is expanded to include all genera of the Noterinae; The genus Suphisellus Crotch is expanded to include species of Pronoterus Sharp syn. n.; and the former subgenus Sternocanthus Guignot stat. rev. is resurrected from synonymy and elevated to genus rank.


Asunto(s)
Organismos Acuáticos/genética , Escarabajos/clasificación , Escarabajos/genética , Filogenia , Animales , Teorema de Bayes , Funciones de Verosimilitud , Modelos Teóricos
13.
Eur Radiol ; 27(3): 1064-1073, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27300193

RESUMEN

OBJECTIVES: To investigate the added value of diffusion-weighted (DW) magnetic resonance (MR) imaging in the detection of infection in pancreatic fluid collections (PFC). METHODS: Forty-patients with PFC requiring endoscopic-transmural drainage underwent conventional-MR and DW-MR imaging (b = 1000 s/mm2) before endoscopy. MR images were divided into two sets (set1, conventional-MR; set2, conventional-MR, DW-MR and ADC maps) and randomized. Two independent readers performed qualitative and quantitative (apparent diffusion coefficient, ADC) image analysis. Bacteriological analysis of PFC content was the gold standard. Non-parametric tests were used for comparisons. Sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV) and accuracy were calculated for the two sets for both readers. Receiver operating characteristic curves (ROC) were drawn to assess quantitative DW-MR imaging diagnostic performance. RESULTS: For both readers, sensitivity, specificity, NPV, PPV and accuracy for infected PFCs were higher for set2 (P > .05). ADC were lower in infected versus non-infected PFCs (P ≤ .031). Minimum ADC cut-off: 1,090×10-3 mm2/s for reader 1 and 1,012×10-3 mm2/s for reader 2 (sensitivity and specificity 67 % and 96 % for both readers). CONCLUSION: Qualitative information provided by DW-MR may help to assess PFCs infection. Infected PFCs show significantly lower ADCs compared to non-infected ones. KEY POINTS: • DW improves MR diagnostic accuracy to detect infection of PFC • Infected PFCs show lower ADC compared to non-infected ones (P < .031) • DW-MR images are easy to interpret especially for non-experienced radiologist.


Asunto(s)
Infecciones Bacterianas/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética/métodos , Enfermedades Pancreáticas/diagnóstico por imagen , Jugo Pancreático/diagnóstico por imagen , Infecciones Bacterianas/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Pancreáticas/patología , Estudios Prospectivos , Curva ROC , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad
14.
Syst Biol ; 64(1): 3-24, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25173563

RESUMEN

During the Cenozoic, Australia experienced major climatic shifts that have had dramatic ecological consequences for the modern biota. Mesic tropical ecosystems were progressively restricted to the coasts and replaced by arid-adapted floral and faunal communities. Whilst the role of aridification has been investigated in a wide range of terrestrial lineages, the response of freshwater clades remains poorly investigated. To gain insights into the diversification processes underlying a freshwater radiation, we studied the evolutionary history of the Australasian predaceous diving beetles of the tribe Hydroporini (147 described species). We used an integrative approach including the latest methods in phylogenetics, divergence time estimation, ancestral character state reconstruction, and likelihood-based methods of diversification rate estimation. Phylogenies and dating analyses were reconstructed with molecular data from seven genes (mitochondrial and nuclear) for 117 species (plus 12 outgroups). Robust and well-resolved phylogenies indicate a late Oligocene origin of Australasian Hydroporini. Biogeographic analyses suggest an origin in the East Coast region of Australia, and a dynamic biogeographic scenario implying dispersal events. The group successfully colonized the tropical coastal regions carved by a rampant desertification, and also colonized groundwater ecosystems in Central Australia. Diversification rate analyses suggest that the ongoing aridification of Australia initiated in the Miocene contributed to a major wave of extinctions since the late Pliocene probably attributable to an increasing aridity, range contractions and seasonally disruptions resulting from Quaternary climatic changes. When comparing subterranean and epigean genera, our results show that contrasting mechanisms drove their diversification and therefore current diversity pattern. The Australasian Hydroporini radiation reflects a combination of processes that promoted both diversification, resulting from new ecological opportunities driven by initial aridification, and a subsequent loss of mesic adapted diversity due to increasing aridity.


Asunto(s)
Escarabajos/clasificación , Variación Genética , Filogenia , Animales , Australia , Escarabajos/genética , Fósiles , Genes de Insecto/genética , Especiación Genética
15.
Endoscopy ; 48(9): 809-16, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27314921

RESUMEN

BACKGROUND AND STUDY AIMS: Diverse endoscopic methods, such as placement of temporary self-expandable stents, have proven effective for the treatment of post-bariatric surgery leaks. However, some patients do not respond to the usual endoscopic treatment. This study tested the efficacy of an alternative treatment strategy based on trans-fistulary drainage with double-pigtail plastic stents. PATIENTS AND METHODS: We performed a retrospective analysis of patients with abdominal collections following bariatric surgery who were treated by trans-fistulary stenting between May 2007 and February 2015. Clinical success was defined as a sustained (> 4 months) clinical resolution (patient discharged from the hospital without antibiotics and able to resume a normal diet) and radiological response. Patient records, radiological images, and the hospital endoscopy database were reviewed. RESULTS: A total of 33 patients (26 women/7 men, mean age 42 years [SD 11.2]) were included. Collections occurred after sleeve gastrectomy (n = 28) or after gastric bypass (n = 5). Fourteen patients were treated by trans-fistulary stenting as primary treatment, and 19 patients had undergone previous unsuccessful endoscopic treatment. No serious complication occurred during the drainage procedure. Clinical success was achieved in 26 patients (78.8 %). In two successfully treated patients, stents are still in place. Spontaneous stent migration occurred in 12 patients. In 12 patients, the stents were removed, either electively (n = 5) or because of complications (ulcerations n = 3, upper gastrointestinal symptoms n = 3, splenic hematoma n = 1). CONCLUSIONS: Trans-fistulary drainage of post-bariatric abdominal collections is safe and associated with high success rates. This technique can be considered in previously untreated patients, when a collection is not properly drained percutaneously, or after failure of other endoscopic treatments.


Asunto(s)
Fuga Anastomótica/cirugía , Fístula del Sistema Digestivo/cirugía , Drenaje/métodos , Endoscopía Gastrointestinal/métodos , Stents , Adulto , Drenaje/instrumentación , Femenino , Gastrectomía/efectos adversos , Derivación Gástrica/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Obesidad/cirugía , Estudios Retrospectivos , Stents/efectos adversos , Resultado del Tratamiento
16.
Mol Phylogenet Evol ; 91: 194-209, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26021440

RESUMEN

The charismatic tropical Polyura Nawab butterflies are distributed across twelve biodiversity hotspots in the Indomalayan/Australasian archipelago. In this study, we tested an array of species delimitation methods and compared the results to existing morphology-based taxonomy. We sequenced two mitochondrial and two nuclear gene fragments to reconstruct phylogenetic relationships within Polyura using both Bayesian inference and maximum likelihood. Based on this phylogenetic framework, we used the recently introduced bGMYC, BPP and PTP methods to investigate species boundaries. Based on our results, we describe two new species Polyura paulettae Toussaint sp. n. and Polyura smilesi Toussaint sp. n., propose one synonym, and five populations are raised to species status. Most of the newly recognized species are single-island endemics likely resulting from the recent highly complex geological history of the Indomalayan-Australasian archipelago. Surprisingly, we also find two newly recognized species in the Indomalayan region where additional biotic or abiotic factors have fostered speciation. Species delimitation methods were largely congruent and succeeded to cross-validate most extant morphological species. PTP and BPP seem to yield more consistent and robust estimations of species boundaries with respect to morphological characters while bGMYC delivered contrasting results depending on the different gene trees considered. Our findings demonstrate the efficiency of comparative approaches using molecular species delimitation methods on empirical data. They also pave the way for the investigation of less well-known groups to unveil patterns of species richness and catalogue Earth's concealed, therefore unappreciated diversity.


Asunto(s)
Mariposas Diurnas/clasificación , Animales , Teorema de Bayes , Biodiversidad , Mariposas Diurnas/anatomía & histología , Mariposas Diurnas/genética , Filogenia , Análisis de Secuencia de ADN
17.
J Hered ; 106(6): 692-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26428282

RESUMEN

The highly modified morphology and ecological features of cave-dwelling organisms are a strong obstacle to dispersion. Hence, they represent ideal models for the study of historical biogeography at both large and fine timescales. Here, we study the phylogeography of Aphaenops cerberus, an endemic hypogean ground beetle with a fragmented distribution in the French Northern Pyrenees. We extracted 75 exemplars of 17 populations of A. cerberus and sequenced one mitochondrial and one nuclear marker to assess the geographic structuration as well as the recent biogeographic history of this species. We used Bayesian Inference and Maximum Likelihood to reconstruct the relationships among most of the extant populations of this species across its distributional range. We inferred divergence time estimates using carabid substitution rates and reconstructed haplotype networks to investigate the recent biogeographic history of this lineage. We recover a strong geographic structuration of the populations across the mountain range. The strong impact of geology on the structure of the populations is evidenced although geological continuity does not systematically lead to continual gene flow. The origin of the species is dated from the Early Pleistocene and the dispersal predates the main Last Glacial Maximum. Our results indicate broad similitudes between islands and karsts, which make cave organisms an excellent model for the study of evolution mechanisms.


Asunto(s)
Escarabajos/genética , Evolución Molecular , Especiación Genética , Genética de Población , Animales , Teorema de Bayes , Cuevas , ADN Mitocondrial/genética , Francia , Haplotipos , Funciones de Verosimilitud , Modelos Genéticos , Filogenia , Filogeografía , Análisis de Secuencia de ADN
18.
Proc Biol Sci ; 281(1782): 20132528, 2014 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-24648218

RESUMEN

The fauna of Bali, situated immediately west of Wallace's Line, is supposedly of recent Javanese origin and characterized by low levels of endemicity. In flightless Trigonopterus weevils, however, we find 100% endemism for the eight species here reported for Bali. Phylogeographic analyses show extensive in situ differentiation, including a local radiation of five species. A comprehensive molecular phylogeny and ancestral area reconstruction of Indo-Malayan-Melanesian species reveals a complex colonization pattern, where the three Balinese lineages all arrived from the East, i.e. all of them transgressed Wallace's Line. Although East Java possesses a rich fauna of Trigonopterus, no exchange can be observed with Bali. We assert that the biogeographic picture of Bali has been dominated by the influx of mobile organisms from Java, but different relationships may be discovered when flightless invertebrates are studied. Our results highlight the importance of in-depth analyses of spatial patterns of biodiversity.


Asunto(s)
Secuencia de Bases , Gorgojos/clasificación , Gorgojos/genética , Animales , Evolución Biológica , Indonesia , Islas , Datos de Secuencia Molecular , Filogeografía , Factores de Tiempo
19.
Endoscopy ; 46(7): 580-7, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24839187

RESUMEN

BACKGROUND AND STUDY AIMS: Paraduodenal pancreatitis is histologically well defined but its epidemiology, natural history, and connection with chronic pancreatitis are not completely understood. The aim of this study was to review the endoscopic and medical management of paraduodenal pancreatitis. PATIENTS AND METHODS: Medical records of all patients with paraduodenal pancreatitis diagnosed by magnetic resonance cholangiopancreatography (MRCP) or endoscopic ultrasonography (EUS) between 1995 and 2010 were retrospectively reviewed. Clinical features, imaging procedures, and treatments were investigated. The primary end point was the rate of clinical success, and the secondary end points were the radiological or endoscopic improvement, complication rate, and overall survival rate. RESULTS: A total of 51 patients were included in the study (88.2 % alcohol abuse; median age 49 years [range 37 - 70]; 50 men). The most frequent symptoms at presentation were pain (n = 50; 98.0 %) and weight loss (n = 36; 70.6 %). Chronic pancreatitis was present in 36 patients (70.6 %), and 45 patients (88.2 %) had cysts. Other findings included stricture of the pancreatic duct (n = 37; 72.5 %), common bile duct (n = 29; 56.9 %), and duodenum (n = 24; 47.1 %). A total of 39 patients underwent initial endoscopic treatment: cystenterostomy (n = 20), pancreatic and/or biliary duct drainage (n = 19), and/or duodenal dilation (n = 6). For the patients with available follow-up (n = 41), 24 patients required repeat endoscopy and 9 patients required surgery after the initial endoscopic management. After a median follow-up of 54 months (range 6 - 156 months), complete clinical success was achieved in 70.7 % of patients, and the overall survival rate was 94.1 %. CONCLUSIONS: This is the largest series concerning the management of paraduodenal pancreatitis using endotherapy as the first-line intervention. Although repeat endoscopic procedures were required in half of the patients, no severe complication was observed and surgical treatment was ultimately needed in less than 25 % of the patients.


Asunto(s)
Endoscopía del Sistema Digestivo/métodos , Pancreatitis/terapia , Adulto , Pancreatocolangiografía por Resonancia Magnética , Terapia Combinada , Drenaje/métodos , Duodeno , Endosonografía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pancreatitis/diagnóstico , Pancreatitis/mortalidad , Estudios Retrospectivos , Esfinterotomía Endoscópica , Stents , Tasa de Supervivencia , Resultado del Tratamiento
20.
Front Zool ; 10(1): 55, 2013 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-24044698

RESUMEN

BACKGROUND: Many scientific disciplines rely on correct taxon delineations and identifications. So does a great part of the general public as well as decision makers. Researchers, students and enthusiastic amateurs often feel frustrated because information about species remains scattered, difficult to access, or difficult to decipher. Together, this affects almost anyone who wishes to identify species or verify identifications. Many remedies have been proposed, but we argue that the role of natural history collections remains insufficiently appreciated. We suggest using state-of-the-art mass imaging technology and to join forces to create a global natural history metacollection on the internet, providing access to the morphology of tens of millions of specimens and making them available for automated digital image analysis. DISCUSSION: Robotic high-resolution imaging technology and fast (high performance) computer-based image stitching make it now feasible to digitize entire collection drawers typically used for arthropod collections, or trays or containers used for other objects. Resolutions of 500 megapixels and much higher are already utilized to capture the contents of 40x50 cm collection drawers, providing amazing detail of specimens. Flanked by metadata entry, this helps to create access to tens of thousands of specimens in days. By setting priorities and combining the holdings of the most comprehensive collections for certain taxa, drawer digitizing offers the unique opportunity to create a global, virtual metacollection.The taxonomic and geographic coverage of such a collection could never be achieved by a single institution or individual. We argue that by joining forces, many new impulses will emerge for systematic biology, related fields and understanding of biodiversity in general.Digitizing drawers containing unidentified, little-curated specimens is a contribution towards the beginning of a new era of online curation. It also will help taxonomists and curators to discover and process the millions of "gems" of undescribed species hidden in museum accessions. SUMMARY: Our proposal suggests creating virtual, high-resolution image resources that will, for the first time in history, provide access for expert scientists as well as students and the general public to the enormous wealth of the world's natural history collections. We foresee that this will contribute to a better understanding, appreciation and increased use of biodiversity resources and the natural history collections serving this cause.

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