The bulbus arteriosus of the holocephalan heart

El resumen aparece en el Program & Abstracts of the 10th International Congress of Vertebrate Morphology, Barcelona 2013.Anatomical Record, Volume 296, Special Feature — 1: P-074.Previous work has shown that the outflow tract of the elasmobranch heart, namely the cardiac portion intercalated between the ventricle and the ventral aorta, does not consist of a single component, the conus arteriosus, as has classically been assumed, but two, the myocardial conus arteriosus and the non-myocardial bulbus arteriosus. From the evolutionary perspective, knowledge of the anatomy of the cardiac outflow tract of the holocephali is important, as they are the sister group of elasmobranchs. Our aim is to describe the cardiac outflow tract of four holocephalan species, two of them, Chimaera monstrosa and Hydrolagus affinis of the family Chimaeridae, and the other two, Harriotta raleighana and Rhinochimaera atlantica, of the family Rhinochimaeridae. The cardiac outflow tract of the four species consisted of a myocardial conus arteriosus, furnished with valves, and a bulbus arteriosus devoid of cardiac muscle. Both the bulbus and conus are tubular in shape. The length of the bulbus relative to the total length of the outflow tract is somewhat smaller in the rhinochimaerids (15%-19%) than in the chimaerids (19%-23%). The bulbus is covered by epicardium and is crossed by the main coronary artery trunks. Histologically, the bulbus is mainly composed of elastin and collagen, and, to a lesser extent, by smooth muscle. This suggests that in holocephalans, the bulbus actively helps to protect the gill vasculature from exposure to high-pressure pulses of blood. Our results prove that the bulbus arteriosus is common to chondrichthyans. In addition, they support the hypothesis that the cardiac outflow tract consisted of a conus arteriosus and a bulbus arteriosus from the beginning of the jawed vertebrate radiation, contributing to our understanding of the morphological changes that have occurred at the arterial pole of the heart in both actinopterygians and sarcopterygians.Proyecto CGL2010-16417/BOS; Fondos FEDE

MYOCARDIAL STRUCTURE AND VASCULARIZATION OF THE HEART VENTRICLE IN HOLOCEPHALI: IMPLICATIONS FOR HEART EVOLUTION

El resumen aparece en el Program & Abstracts of the 10th International Congress of Vertebrate Morphology, Barcelona 2013. Anatomical Record, Volume 296, Special Feature — 1: P-075.It has been classically assumed that the ventricle of the primitive vertebrate heart is composed of spongy myocardium, supplied exclusively by oxygen-poor, luminal blood. This idea is on two facts: (1) extant agnathans have a spongy ventricular myocardium, and (2) in avian and mammalian embryos, the formation of trabeculated myocardium precedes the appearance of compact myocardium. Recently, it has been proposed that, like elasmobranchs, the early gnathostomes possess a fully vascularised ventricle composed of mixed myocardium. We tested this idea by studying the structure and vascularisation of the ventricular myocardium in four holocephalan species of the families Chimaeridae and Rhinochimaeridae. Chimaera monstrosa, Hidrolagus affinis and Harriotta raleighana have a spongy myocardium covered by a thin layer of cardiac muscle. In H. raleighana, the compacta is reduced to an extremely fine rim. In all three species there is a well-developed coronary artery system consisting of subepicardial vessels which give off branches that penetrate the myocardial trabeculae. Rhinochimaera atlantica has no compacta and its ventricular coronary artery system is reduced to subepicardial vessels that do not enter the spongy layer. This report is the first to show that in wild living vertebrates, a coronary artery system supplying the whole myocardium exists in the absence of a well-developed compacta, which supports experimental work that shows that myocardial cell proliferation and coronary vascular growth rely on genetically separated programs. We conclude that the mixed ventricular myocardium is primitive for chondrichthyans, and that the lack of compacta in some holocephalans is a derived character. Moreover our results support the hypotheses that the mixed myocardium is the primitive condition in gnathostomes, and that the absence of a compacta in different actinopterygian taxa is the result of its repeated loss during evolution.Proyecto CGL2010-16417/BOS; Fondos FEDE

The Myosin Heavy Chain specific A4.1025 antibody discriminates different cardiac segments in ancient groups of gnathostomes: Morphological and evolutionary implications

El resumen aparece en el Program & Abstracts of the 11th International Congress of Vertebrate Morphology, Washington DC 2016. Anatomical Record, Volume 299, Special Feature: 263.The pan-Myosin Heavy Chain (pan-MyHC) marker MF20 have been reported to show similar, homogeneous signal in the myocardial segments of the heart of teleosts and tetrapods. However, in an ongoing study of the myocardial structure of the dogfish (Scyliorhinus canicula; Chondrichthyes), we observed differential immunostaining of the cardiac segments using another pan-MyHC, the A4.1025 antibody. In order to investigate the relevance of this finding for better understanding of the morphology and evolution of the vertebrate heart, we performed immunohistochemistry, slot blot and western blot in several species of chondrichthyans, actinopterygians and mammals using the above mentioned antibodies. In the dogfish heart, A4.1025 and MF20 specifically recognized MyHC isoforms, although with different degree of affinity. MF20 reactivity was homogeneous and high in all the myocardial segments. However, A4.1025 reactivity was heterogeneous. It was high in the sinus venosus (external layer), atrium and atrioventricular region, low in the ventricle and conus arteriosus, and null in the internal layer of the sinus venosus. A heterogeneous pattern of A4.1025 immunoreactivity was also detected in two other elasmobranchs, a holocephalan, a polypteryform and an acipenseriform. In all of these species, MF20 immunoreactivity was homogeneous. In addition, both markers showed a homogeneous immunoreactivity pattern in teleosts and mammals. Our results indicate that in the hearts of ancient gnathostomes, in all of which a conspicuous conus arteriosus exists, one or more MyHC isoforms with low affinity for A4.1025 show segment-specific distributions. Thus, A4.1025 appears to be an appropriated marker to identify the cardiac segments and their boundaries. We propose that the segmentspecific distribution of MyHC isoforms may generate a particular type of myocardial contractility associated with the presence of a conus arteriosus.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. CGL2014-52356-P, CEIMAR, BIO 203, FEDE

Anatomical, histochemical and immunohistochemical characterization of the outflow tract of ray hearts (Rajiformes; Chondrichthyes)

El resumen aparece en el Program & Abstracts of the 11th International Congress of Vertebrate Morphology, Washington DC 2016. Anatomical Record, Volume 299, Special Feature: 264.Recent work has shown that the cardiac outflow tract of sharks and chimaeras does not consist of a single myocardial component, the conus arteriosus, as classically accepted, but two, namely, the myocardial conus arteriosus and the non-myocardial bulbus arteriosus. However, the anatomical composition of the outflow tract of the batoid hearts remains unknown. The present study was designed to fill this gap. The material examined consisted of hearts of two species of rays, namely, the Mediterranean starry ray (Raja asterias) and sandy ray (Leucoraja circularis). They were studied using scanning electron microscopy, and histochemical and inmunohistochemical techniques. In both species, the outflow tract consists of two components, proximal and distal with regard to the ventricle. The proximal component is the conus arteriosus; it is characterized by the presence of compact myocardium in its wall and several transverse rows of pocket-shaped valves at its luminal side. Each valve consists of a leaflet and its supporting sinus. Histologically, the leaflet has two fibrosas, inner and outer, and a middle coat, the spongiosa. The distal component lacks myocardium. Its wall consists of smooth muscle cells, elastic fibers and collagen. Thus, it shows an arterial-like structure. However, it differs from the aorta because it is covered by the epicardium and crossed by coronary arteries. These findings indicate that the distal component is morphologically equivalent to the bulbus arteriosus of sharks and chimaeras. In contrast to foregoing descriptions, the valves of the first transverse row are distally anchored to the bulbus arteriosus and not to the ventral aorta. Our findings give added support to the notion that presence of a bulbus arteriosus at the arterial pole of the heart is common to all chondrichtyans, and not an apomorphy of actinopterygians as classically thought.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. CGL2014-52356-P, CEIMAR, BIO 203, FEDE

La configuración del tracto de salida cardiaco en los vertebrados pisciformes

La noción clásica relativa a la anatomía del corazón de los vertebrados pisciformes ha cambiado notablemente en los últimos años. Anteriormente se asumía que el tracto de salida cardiaco de los condrictios es estructuralmente diferente del de los teleósteos. En los primeros, el tracto de salida es de naturaleza miocárdica y se denomina cono arterioso, mientras que en los segundos se denomina bulbo arterioso y carece de musculatura cardiaca. Según esta noción clásica, en el curso de la evolución de los actinopterigios, el cono arterioso habría disminuido su tamaño de forma concomitante con la aparición y desarrollo del bulbo arterioso. No obstante, algunos trabajos antiguos en los que se describe el corazón de determinadas especies de condrictios y de actinopterigios no teleósteos, tales como los polipteriformes, refieren que el tracto de salida consta de dos porciones, una miocárdica, proximal con respecto al ventrículo, y otra, distal, no miocárdica. Investigaciones recientes han puesto de manifiesto que el tracto de salida cardiaco de los condrictios está constituido en realidad por un componente proximal, el cono arterioso, de naturaleza miocárdica, y un componente distal, no miocárdico, homólogo al bulbo arterioso de los actinopterigios. Estos dos componentes coexisten también en el polo arterioso de los polipterifomes. Asimismo, se ha observado que el cono arterioso está presente en todos los grupos de teleósteos. Este componente cardiaco está muy reducido e incluso llega a ser vestigial tanto en grupos que divergieron tempranamente, como los osteoglosomorfos, como en grupos apicales, tales como los perciformes. En conclusión, en contraposición a la noción clásica, el polo arterioso de todos los vertebrados pisciformes está constituido por dos componentes, uno proximal y el otro distal con respecto al ventrículo, que son el cono arterioso y el bulbo arterioso. Esta configuración se ha conservado en el curso de la evolución de los diversos grupos de vertebrados pisciformes.CGL2014-52356-P (Ministerio de Economía y Competitividad), FPU15/03209 (Ministerio de Educación, Cultura y Deporte), fondos FEDER. Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Millimagnitude Photometry for Transiting Extrasolar Planetary Candidates IV: The Puzzle of the Extremely Red OGLE-TR-82 Primary Solved

We present precise new V, I, and K-band photometry for the planetary transit candidate star OGLE-TR-82. Good seeing V-band images acquired with VIMOS instrument at ESO VLT allowed us to measure V=20.6+-0.03 mag star in spite of the presence of a brighter neighbour about 1" away. This faint magnitude answers the question why it has not been possible to measure radial velocities for this object. One transit of this star has been observed with GMOS-S instrument of GEMINI-South telescope in i and g-bands. The measurement of the transit allows us to verify that this is not a false positive, to confirm the transit amplitude measured by OGLE, and to improve the ephemeris. The transit is well defined in i-band light curve, with a depth of A_i=0.034 mag. It is however, less well defined, but deeper (A_g=0.1 mag) in the g-band, in which the star is significantly fainter. The near-infrared photometry obtained with SofI array at the ESO-NTT yields K=12.2+-0.1 and V-K=8.4+-0.1, so red that it is unlike any other transit candidate studied before. Due to the extreme nature of this object, we have not yet been able to measure velocities for this star, but based on the new data we consider two different possible configurations:(1) a nearby M7V star, or (2) a blend with a very reddened distant red giant. The nearby M7V dwarf hypothesis would give a radius for the companion of R_p=0.3+-0.1 R_J, i.e. the size of Neptune. Quantitative analysis of near-IR spectroscopy finally shows that OGLE-TR-82 is a distant, reddened metal poor early K giant. This result is confirmed by direct comparison with stellar templates that gives the best match for a K3III star. Therefore, we discard the planetary nature of the companion. Based on all the new data, we conclude that this system is a main-sequence binary blended with a background red giant.Comment: 26 pages, 9 figures, ApJ accepte

ALMA observations of Elias 2–24: a protoplanetary disk with multiple gaps in the Ophiuchus molecular cloud

We present ALMA 1.3 mm continuum observations at 0. 2 (25 au) resolution of Elias 2–24, one of the largest and brightest protoplanetary disks in the Ophiuchus Molecular Cloud, and we report the presence of three partially resolved concentric gaps located at ∼20, 52, and 87 au from the star. We perform radiative transfer modeling of the disk to constrain its surface density and temperature radial profile and place the disk structure in the context of mechanisms capable of forming narrow gaps such as condensation fronts and dynamical clearing by actively forming planets. In particular, we estimate the disk temperature at the locations of the gaps to be 23, 15, and 12 K (at 20, 52, and 87 au, respectively), very close to the expected snowlines of CO (23–28 K) and N2 (12–15 K). Similarly, by assuming that the widths of the gaps correspond to 4–8× the Hill radii of forming planets (as suggested by numerical simulations), we estimate planet masses in the range of 0.2 1.5 – MJup, 1.0 8.0 – MJup, and 0.02 0.15 – MJup for the inner, middle, and outer gap, respectively. Given the surface density profile of the disk, the amount of “missing mass” at the location of each one of these gaps (between 4 and 20 MJup) is more than sufficient to account for the formation of such planets.Fil: Cieza, Lucas A.. Universidad Diego Portales; ChileFil: Casassus, Simon. Universidad de Chile; ChileFil: Pérez, Sebastian. Universidad de Chile; ChileFil: Hales, Antonio. Alma Observatory; ChileFil: Cárcamo, Miguel. Universidad de Chile; ChileFil: Ansdell, Megan. University of California at Berkeley; Estados UnidosFil: Avenhaus, Henning. Universitat Zurich; SuizaFil: Bayo, Amelia. Universidad de Valparaiso; ChileFil: Bertrang, Gesa H.-M.. Universidad Diego Portales; ChileFil: Cánovas, Hector. Agencia Espacial Europea; EspañaFil: Christiaens, Valentin. Universidad de Chile; ChileFil: Dent, William. Alma Observatory; ChileFil: Ferrero, Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; ArgentinaFil: Gamen, Roberto Claudio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; ArgentinaFil: Olofsson, Johan. Universidad de Valparaiso; ChileFil: Orcajo, Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; ArgentinaFil: Osses, Axel. Universidad de Chile; ChileFil: Peña Ramirez, Karla. Universidad de Antofagasta; ChileFil: Principe, David. Massachusetts Institute of Technology; Estados UnidosFil: Ruíz Rodríguez, Dary. Rochester Institute Of Technology; Estados UnidosFil: Schreiber, Matthias R.. Universidad de Valparaiso; ChileFil: Plas, Gerrit van der. Univ. Grenoble Alpes; SuizaFil: Williams, Jonathan P.. Institute For Astronomy, University Of Hawaii; Estados UnidosFil: Zurlo, Alice. Universidad Diego Portales; Chil

The challenge of sustainability: Long-term results from the Fifty-Fifty peer group-based intervention in cardiovascular risk factors.

The Fifty-Fifty trial demonstrated that a peer-group-based intervention was able to improve healthy behaviors in individuals with cardiovascular (CV) risk factors immediately post-intervention. To determine the long-term sustainability of a one-year peer-group-based intervention focused on CV health and behavior. A total of 543 adults aged 25 to 50 years with at least 1 CV risk factor were screened and recruited, received initial training through workshops, and were then randomized 1:1 to a peer-group-based intervention group (IG) or a self-management control group (CG) for 12 months. At a median of 52 months from baseline, 321 participants were re-assessed (~60% retention). The primary outcome was the mean change in a composite health score related to blood pressure, exercise, weight, alimentation, and tobacco use (Fuster-BEWAT score [FBS], range 0-15). Intervention effects were assessed using linear-mixed effects models. The mean age of retained participants was 48.0 years (SD: 5.4), and 73% were female. Consistent with previous results, the change of overall FBS was significantly greater in the IG than in the CG at 12-month follow-up (between-group difference, 0.60 points; 95% CI, 0.08-1.12; P = .025). Assessment of long-term sustainability (52-month follow-up) showed that there were no between-group differences in the mean overall FBS (IG mean score, 8.52; 95% CI, 7.97-9.07 vs CG mean score, 8.51; 95% CI, 7.93-9.10; P = .972) or in the change of overall FBS from screening (IG mean change, 0.64; 95% CI, 0.00-1.28; CG mean change, 0.46; 95% CI, -0.20-1.12; P = .497). A one-year peer-group-based intervention showed favorable results at immediate post-intervention but did not demonstrate significant differences between the IG and CG at 52 months. Combination of an initial training period (workshops) with the maintenance of peer-support groups or other re-intervention strategies may be required to achieve sustained effects on healthy behaviors. ClinicalTrials.gov identifier NCT02367963. Registered (https://clinicaltrials.gov/show/NCT02367963).This study was co-funded by the SHE Foundation -“la Caixa” Foundation (LCF/PR/CE16/10700001 and LCF/PR/MS19/12220001) and the Ministry of Health, Social Services and Equality. R.F-J is recipient of funding from the Instituto de Salud Carlos III-Fondo de Investigacion Sanitaria (PI19/01704) co-funded by the European Regional Development Fund/European Social Fund (“A way to make Europe”/“Investing in your future”). The CNIC is supported by the Instituto de Salud Carlos III (ISCIII), the Ministry of Science and Innovation, and the Pro CNIC Foundation and is a Severo Ochoa Center of Excellence (SEV-2015-0505).S

HSP90 inhibition causes heterochronies in the skull ossification sequences of Pleurodeles waltl (Urodela). Evolutionary implications.

Heat-shock protein 90 (HSP90) is an ubiquitous chaperone in eukaryotes that facilitates folding of proteins both in normal conditions and in response to environmental stress. In addition, HSP90 is able to buffer genetic variation resulting from random mutations by regulating intracellular protein degradation mechanisms. It has been shown that experimental HSP90 inhibition produces anatomical variability during embryonic development in Arabidopsis, Drosophila and zebrafish. It is not clear whether these anatomical changes are caused by the expression of genomic cryptic mutations or by modifications of HSP90 dependent molecular pathways. However, several results suggest that HSP90 modulation is a relevant mechanism underlying the de novo appearance of character states. In order to test whether HSP90 is involved in the generation of apomorphic phenotypes in tetrapods, we pharmacologically inhibited HSP90 in Pleurodeles waltl (Urodela) embryos (n=141), by exposition to 10 µM Radicicol during the first 24 hours of development. Control specimens (n=20) received no treatment. The 54 surviving larvae were euthanatized at stages 46 (n=25) and 50 (n=29), and subjected to whole-mount double staining with alcian blue and alizarin red. All the control and 7 (13%) of the treated specimens were phenotypically normal. The remaining 47 (87%) larvae showed 20 abnormal phenotypes best described as heterochronic skull ossification sequences. Interestingly, these heterochronies fit the ossification sequences described in other urodele families. We propose that modulation of HSP90 function during the embryonic development, caused naturally by environmental stress, may underlay the evolutive modifications of skull ossification sequences in urodeles. New studies on the inheritance of the phenotypes obtained in untreated embryos from treated parents may confirm the plausibility of this hypothesis.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. FPU15/03209, EST17/00194 and University of Málaga

Unsupervised Segmentation of Fetal Brain MRI using Deep Learning Cascaded Registration

Accurate segmentation of fetal brain magnetic resonance images is crucial for analyzing fetal brain development and detecting potential neurodevelopmental abnormalities. Traditional deep learning-based automatic segmentation, although effective, requires extensive training data with ground-truth labels, typically produced by clinicians through a time-consuming annotation process. To overcome this challenge, we propose a novel unsupervised segmentation method based on multi-atlas segmentation, that accurately segments multiple tissues without relying on labeled data for training. Our method employs a cascaded deep learning network for 3D image registration, which computes small, incremental deformations to the moving image to align it precisely with the fixed image. This cascaded network can then be used to register multiple annotated images with the image to be segmented, and combine the propagated labels to form a refined segmentation. Our experiments demonstrate that the proposed cascaded architecture outperforms the state-of-the-art registration methods that were tested. Furthermore, the derived segmentation method achieves similar performance and inference time to nnU-Net while only using a small subset of annotated data for the multi-atlas segmentation task and none for training the network. Our pipeline for registration and multi-atlas segmentation is publicly available at https://github.com/ValBcn/CasReg.Comment: 17 pages, 8 figures, 5 tables, paper submitted to IEEE transaction on medical imagin