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3.
Mol Phylogenet Evol ; 111: 110-131, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28263876

RESUMEN

Sea cucumbers (Holothuroidea) are a morphologically diverse, ecologically important, and economically valued clade of echinoderms; however, the understanding of the overall systematics of the group remains controversial. Here, we present a phylogeny of extant Holothuroidea assessed with maximum parsimony, maximum likelihood, and Bayesian approaches using approximately 4.3kb of mt- (COI, 16S, 12S) and nDNA (H3, 18S, 28S) sequences from 82 holothuroid terminals representing 23 of the 27 widely-accepted family-ranked taxa. Currently five holothuroid taxa of ordinal rank are accepted. We find that three of the five orders are non-monophyletic, and we revise the taxonomy of the groups accordingly. Apodida is sister to the rest of Holothuroidea, here considered Actinopoda. Within Actinopoda, Elasipodida in part is sister to the remaining Actinopoda. This latter clade, comprising holothuroids with respiratory trees, is now called Pneumonophora. The traditional Aspidochirotida is paraphyletic, with representatives from three orders (Molpadida, Dendrochirotida, and Elasipodida in part) nested within. Therefore, we discontinue the use of Aspidochirotida and instead erect Holothuriida as the sister group to the remaining Pneumonophora, here termed Neoholothuriida. We found four well-supported major clades in Neoholothuriida: Dendrochirotida, Molpadida and two new clades, Synallactida and Persiculida. The mapping of traditionally-used morphological characters in holothuroid systematics onto the phylogeny revealed marked homoplasy in most characters demonstrating that further taxonomic revision of Holothuroidea is required. Two time-tree analyses, one based on calibrations for uncontroversial crown group dates for Eleutherozoa, Echinozoa and Holothuroidea and another using these calibrations plus four more from within Holothuroidea, showed major discrepancies, suggesting that fossils of Holothuroidea may need reassessment in terms of placing these forms with existing crown clades.


Asunto(s)
Extinción Biológica , Filogenia , Pepinos de Mar/clasificación , Animales , Teorema de Bayes , Fósiles , Funciones de Verosimilitud , Pepinos de Mar/genética , Análisis de Secuencia de ADN , Factores de Tiempo
4.
Zootaxa ; 4052(3): 332-44, 2015 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-26701433

RESUMEN

The dates of publication of Hubert Ludwig's (1852-1913) comprehensive monograph Die Seewalzen [= Sea cucumbers] are reviewed. The precise publication dates of his volume, originally published in 16 fascicles and 8 parts/issues, delivered between 1889 and 1892, has been re-examined. Additionally, a short biographical note on Hubert Ludwig's life and a discussion of all new taxa introduced by him in his monograph is given.


Asunto(s)
Publicaciones/historia , Pepinos de Mar/clasificación , Animales , Libros/historia , Alemania , Historia del Siglo XIX , Historia del Siglo XX
5.
PLoS One ; 7(10): e46913, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23071660

RESUMEN

The origin and possible antiquity of the spectacularly diverse modern deep-sea fauna has been debated since the beginning of deep-sea research in the mid-nineteenth century. Recent hypotheses, based on biogeographic patterns and molecular clock estimates, support a latest Mesozoic or early Cenozoic date for the origin of key groups of the present deep-sea fauna (echinoids, octopods). This relatively young age is consistent with hypotheses that argue for extensive extinction during Jurassic and Cretaceous Oceanic Anoxic Events (OAEs) and the mid-Cenozoic cooling of deep-water masses, implying repeated re-colonization by immigration of taxa from shallow-water habitats. Here we report on a well-preserved echinoderm assemblage from deep-sea (1000-1500 m paleodepth) sediments of the NE-Atlantic of Early Cretaceous age (114 Ma). The assemblage is strikingly similar to that of extant bathyal echinoderm communities in composition, including families and genera found exclusively in modern deep-sea habitats. A number of taxa found in the assemblage have no fossil record at shelf depths postdating the assemblage, which precludes the possibility of deep-sea recolonization from shallow habitats following episodic extinction at least for those groups. Our discovery provides the first key fossil evidence that a significant part of the modern deep-sea fauna is considerably older than previously assumed. As a consequence, most major paleoceanographic events had far less impact on the diversity of deep-sea faunas than has been implied. It also suggests that deep-sea biota are more resilient to extinction events than shallow-water forms, and that the unusual deep-sea environment, indeed, provides evolutionary stability which is very rarely punctuated on macroevolutionary time scales.


Asunto(s)
Biodiversidad , Evolución Biológica , Equinodermos/crecimiento & desarrollo , Fósiles , Animales , Equinodermos/clasificación , Geografía , Biología Marina/métodos , Océanos y Mares , Paleontología/métodos
6.
PLoS One ; 6(10): e25693, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22022431

RESUMEN

BACKGROUND: Archosaurs (birds, crocodilians and their extinct relatives including dinosaurs) dominated Mesozoic continental ecosystems from the Late Triassic onwards, and still form a major component of modern ecosystems (>10,000 species). The earliest diverse archosaur faunal assemblages are known from the Middle Triassic (c. 244 Ma), implying that the archosaur radiation began in the Early Triassic (252.3-247.2 Ma). Understanding of this radiation is currently limited by the poor early fossil record of the group in terms of skeletal remains. METHODOLOGY/PRINCIPAL FINDINGS: We redescribe the anatomy and stratigraphic position of the type specimen of Ctenosauriscus koeneni (Huene), a sail-backed reptile from the Early Triassic (late Olenekian) Solling Formation of northern Germany that potentially represents the oldest known archosaur. We critically discuss previous biomechanical work on the 'sail' of Ctenosauriscus, which is formed by a series of elongated neural spines. In addition, we describe Ctenosauriscus-like postcranial material from the earliest Middle Triassic (early Anisian) Röt Formation of Waldhaus, southwestern Germany. Finally, we review the spatial and temporal distribution of the earliest archosaur fossils and their implications for understanding the dynamics of the archosaur radiation. CONCLUSIONS/SIGNIFICANCE: Comprehensive numerical phylogenetic analyses demonstrate that both Ctenosauriscus and the Waldhaus taxon are members of a monophyletic grouping of poposauroid archosaurs, Ctenosauriscidae, characterised by greatly elongated neural spines in the posterior cervical to anterior caudal vertebrae. The earliest archosaurs, including Ctenosauriscus, appear in the body fossil record just prior to the Olenekian/Anisian boundary (c. 248 Ma), less than 5 million years after the Permian-Triassic mass extinction. These earliest archosaur assemblages are dominated by ctenosauriscids, which were broadly distributed across northern Pangea and which appear to have been the first global radiation of archosaurs.


Asunto(s)
Evolución Biológica , Dinosaurios/anatomía & histología , Filogeografía , Animales , Dinosaurios/genética , Fósiles , Alemania , Paleontología , Filogenia , Factores de Tiempo
7.
Clin Cancer Res ; 17(10): 3378-87, 2011 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-21558397

RESUMEN

PURPOSE: Inappropriate activation of the Hedgehog (Hh) signaling pathway in skin is critical for the development of basal cell carcinomas (BCC). We have investigated the anti-BCC efficacy of topically-applied CUR61414, an inhibitor of the Hh signal transduction molecule Smoothened. EXPERIMENTAL DESIGN: In preclinical studies, we used a depilatory model to evaluate the ability of topical formulations of CUR61414 to repress Hh responsive cells found at the base of hair follicles in normal skin. We also tested the in vivo effects of topical CUR61414 on murine BCCs developed in Ptch1 (+/-) K14-CreER2 p53 fl/fl mice. In a phase I clinical study, we evaluated the safety, tolerability, and efficacy of a multidose regimen of CUR61414 (0.09%, 0.35%, 1.1%, and 3.1%) applied topically to human superficial or nodular BCCs for up to 28 days. RESULTS: In mice, topical CUR61414 significantly inhibited skin Hh signaling, blocked the induction of hair follicle anagen, and shrank existing BCCs. However, we observed no clinical activity of this formulation in human superficial or nodular BCCs in a phase I clinical study. CONCLUSIONS: Our data highlight some of the challenges of translating preclinical experience into successful human results for a topical anticancer agent.


Asunto(s)
Carcinoma Basocelular/tratamiento farmacológico , Dioxoles/administración & dosificación , Piperazinas/administración & dosificación , Receptores Acoplados a Proteínas G/antagonistas & inhibidores , Neoplasias Cutáneas/tratamiento farmacológico , Administración Tópica , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Carcinoma Basocelular/genética , Dioxoles/efectos adversos , Método Doble Ciego , Sistemas de Liberación de Medicamentos/métodos , Evaluación Preclínica de Medicamentos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Piperazinas/efectos adversos , Placebos , Neoplasias Cutáneas/genética , Bibliotecas de Moléculas Pequeñas/análisis , Receptor Smoothened , Resultado del Tratamiento
8.
Exp Eye Res ; 85(4): 425-30, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17714704

RESUMEN

Neovascular age-related macular degeneration (AMD) is the leading cause of blindness in older adults in the Western world. Ranibizumab (Lucentis), a humanized antibody fragment directed against vascular endothelial growth factor (VEGF-A), was recently approved by the US Food and Drug Administration (FDA) for the treatment of neovascular AMD. The objective of this study was to characterize the binding affinity and pharmacological activity of ranibizumab for 3 biologically active forms of VEGF-A: VEGF165, VEGF121, and VEGF110. The apparent equilibrium binding affinity of ranibizumab for VEGF-A molecules was determined by Biacore analysis; the biological activity of VEGF-A was demonstrated in a human umbilical vein endothelial cell (HUVEC) proliferation-inhibition assay. Inhibition of VEGF-A-induced vascular permeability by ranibizumab was assessed in vivo using hairless guinea pigs and a modified Miles assay. Ranibizumab was capable of binding to recombinant human VEGF165, VEGF121, and VEGF110 (KD < or = 192 pM), inhibiting VEGF-A-induced HUVEC proliferation in a concentration-dependent manner. Ranibizumab also exerted potent dose-dependent inhibition (IC(50) of 0.4-1.2 nM) of the vascular permeability-enhancing activity of VEGF165, VEGF121, and VEGF110 in the Miles assay. In conclusion, these results show that ranibizumab is capable of binding to and specifically inhibiting the activities of 3 biologically active forms of VEGF-A. As VEGF-A plays a pivotal role in the pathogenesis of neovascular AMD, ranibizumab activity, as demonstrated in this study, supports its clinical utility in the treatment of this disease.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Anticuerpos Monoclonales/farmacología , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Inhibidores de la Angiogénesis/metabolismo , Animales , Anticuerpos Monoclonales/metabolismo , Anticuerpos Monoclonales Humanizados , Permeabilidad Capilar/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Endotelio Vascular/citología , Endotelio Vascular/efectos de los fármacos , Cobayas , Humanos , Ranibizumab , Proteínas Recombinantes/metabolismo , Piel/irrigación sanguínea , Factor A de Crecimiento Endotelial Vascular/metabolismo , Factor A de Crecimiento Endotelial Vascular/farmacología
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