Hidden chromosomal abnormalities in pleuropulmonary blastomas identified by multiplex FISH

BACKGROUND: Pleuropulmonary blastoma (PPB) is a rare childhood dysontogenetic intrathoracic neoplasm associated with an unfavourable clinical behaviour. CASES PRESENTATION: We report pathological and cytogenetic findings in two cases of PPB at initial diagnosis and recurrence. Both tumors were classified as type III pneumoblastoma and histological findings were similar at diagnosis and relapse. In both cases, conventional cytogenetic techniques revealed complex numerical and structural chromosomal abnormalities. Molecular cytogenetic analysis (interphase/metaphase FISH and multicolor FISH) identified accurately chromosomal aberrations. In one case, TP53 gene deletion was detected on metaphase FISH. To date, only few cytogenetic data have been published about PPB. CONCLUSION: The PPB genetic profile remains to be established and compared to others embryonal neoplasia. Our cytogenetic data are discussed reviewing cytogenetics PPBs published cases, illustrating the contribution of multicolor FISH in order to identify pathogenetically important recurrent aberrations in PPB

Micro-connectomics: probing the organization of neuronal networks at the cellular scale.

Defining the organizational principles of neuronal networks at the cellular scale, or micro-connectomics, is a key challenge of modern neuroscience. In this Review, we focus on graph theoretical parameters of micro-connectome topology, often informed by economical principles that conceptually originated with Ramón y Cajal's conservation laws. First, we summarize results from studies in intact small organisms and in samples from larger nervous systems. We then evaluate the evidence for an economical trade-off between biological cost and functional value in the organization of neuronal networks. Various results suggest that many aspects of neuronal network organization are indeed the outcome of competition between these two fundamental selection pressures.This work was supported by the National Institute of Health Research (NIHR) Cambridge Biomedical Research Centre.This is the author accepted manuscript. It is currently under an indefinite embargo pending publication by the Nature Publishing Group

Parasitofauna study of the brown trout, Salmo trutta (Pisces, Teleostei) from Corsica (Mediterranean island) rivers

Corsica is a mediterranean island characterised by a great number of rivers. Salmonides are the main fishes which populate these rivers. Very appreciated by fishermen, Salmonides are represented by three species in the insular hydrographical network, among which an autochthonous species, the brown trout (Salmo trutta). In the present work, we have analysed the parasitofauna of this species. According to our knowledge, this research has never been carried out in Corsica. In a first step, we drew up an inventory of the parasites found in this freshwater fish. In a second step, we studied the differences which appeared in the composition of parasite communities of this species

Parasitofauna study of the brown trout,

Corsica is a mediterranean island characterised by a great number of rivers. Salmonides are the main fishes which populate these rivers. Very appreciated by fishermen, Salmonides are represented by three species in the insular hydrographical network, among which an autochthonous species, the brown trout (Salmo trutta). In the present work, we have analysed the parasitofauna of this species. According to our knowledge, this research has never been carried out in Corsica. In a first step, we drew up an inventory of the parasites found in this freshwater fish. In a second step, we studied the differences which appeared in the composition of parasite communities of this species

Sperm ultrastructure of Helicometra epinepheli (Platyhelminthes, Digenea, Opecoelidae), parasite of Epinephelus fasciatus (Pisces, Teleostei)

This paper describes the ultrastructure of the mature spermatozoon of the digenean Helicometra epinepheli. The ultrastructural elements observed are: two axonemes with a 9+“1” pattern of Trepaxonemata, four attachment zones, a nucleus, two mitochondria, external ornamentation of the plasma membrane, spinelike bodies and cortical microtubules. A particularity of this spermatozoon is the presence of an apical cone. However, the spermatozoon presents the general pattern of the Opecoelidae and thus differs from Helicometra fasciata (which appears as an exception in this family) by several ultrastructural features: the presence of external ornamentation and spine-like bodies and the arrangement of cortical microtubules around the first mitochondrion in the region of the ornamentation. Each ultrastructural feature is discussed and compared with the literature to highlight characters which could be useful for phylogeny

Ultrastructure of the spermatozoon of Helicometroides atlanticus (Digenea, Monorchiidae), an intestinal parasite of Parapristipoma octolineatum (Pisces, Teleostei) in Senegal

International audienc

Sperm ultrastructure of the digenean Siphoderina elongata (Platyhelminthes, Cryptogonimidae) intestinal parasite of Nemipterus furcosus (Pisces, Teleostei)

The ultrastructure of the spermatozoon of Siphoderina elongata was studied by transmission electron microscopy. A description and drawings of the mature spermatozoon are presented in this paper. Several ultrastructural elements of this male gamete have been observed: a nucleus, two mitochondria, two axonemes of 9 + "1" pattern, external ornamentation of the plasma membrane, spine-like bodies and cortical microtubules. The presence, the location or the number of these elements have been compared with other digenean spermatozoa. Moreover, a close attention was paid to the organization of the external ornamentation region. This zone presents a single row of cortical microtubules disposed in a semi-circle around a mitochondrion and associated with external ornamentation and spine-like bodies. The aim of this study is to highlight criteria which can be interesting in Platyhelminthes phylogeny

Inelastic scattering of light by magnetic excitons in the pseudo Ising antiferromagnets K2CoF4 and Rb2CoF4

In addition to previously reported phonon Raman scattering, we have observed inelastic light scattering by magnetic excitons in K2CoF 4 and Rb2CoF4 ; the polarized spectra have been studied at low temperatures under an applied magnetic field up to about 5 teslas. The results are interpreted on the basis of a multilevel propagating exciton model deduced from a Hamiltonian including the single ion spin-orbit coupling, the low symmetry crystal field and a nearest neighbours Heisenberg exchange interaction, acting in the 4Γ+4 (Oh) ground state of Co 2+. From the lowest exciton study we derive a value of the tetragonal crystal field Δ (— 425 cm-1 and — 635 cm -1, respectively in K2CoF4 and Rb2CoF 4) and of the isotropic exchange parameter J ( — 11.55 cm-1 and — 9.65 cm-1, respectively in K 2CoF4 and Rb2CoF4). The remaining features of the spectra, which include one and two exciton scattering, are partly interpreted using the above model with these values. The derived J values are close to previous determinations in KCoF3 and RbCoF 3, as expected. The Ising character, which is caused by the low symmetry crystal field, is found to be less marked when evaluated from the magnon dispersion results than it was indicated by previous magnetic measurements, and this has been confirmed by recent inelastic neutron scattering data in Rb2CoF 4.Outre l'effet Raman dû aux phonons, antérieurement signalé, nous observons la diffusion inélastique de la lumière liée aux excitons magnétiques dans K2CoF4 et Rb2CoF4 ; les spectres polarisés ont été étudiés à basse température en présence d'un champ magnétique pouvant atteindre 5 teslas environ. Nous interprétons les résultats au moyen d'un modèle multi-excitonique déduit d'un Hamiltonien tenant compte du couplage spin-orbite, du champ cristallin de basse symétrie et d'une interaction d'échange de type Heisenberg, perturbant l'état fondamental 4Γ+4 (Oh) des ions Co2+. De l'étude de l'exciton de plus basse énergie, nous déduisons la valeur du champ cristallin quadratique Δ (— 425 cm-1 et — 635 cm -1, respectivement pour K2CoF4 et Rb2CoF 4) ainsi que celle du paramètre d'échange isotrope J (— 11,55 cm-1 et — 9,65 cm-1, respectivement pour K2CoF4 et Rb2CoF4). Le reste du spectre, qui contient des contributions à la diffusion par un et par deux excitons, est partiellement interprété, grâce au modèle ci-dessus décrit, pour les valeurs ainsi déterminées des paramètres Δ et J, dont il dépend. Les valeurs de J sont voisines de celles qui ont été antérieurement trouvées pour KCoF 3 et RbCoF3, comme prévu. Le comportement de type Ising, qui provient du champ cristallin de basse symétrie apparaît moins marqué lorsqu'on l'évalue à partir de la courbe de dispersion des magnons que ne le laissaient prévoir d'anciennes mesures magnétiques, résultat confirmé par une récente étude de diffusion inélastique de neutrons dans Rb2CoF4