Mathematical birth of Early Afterdepolarizations in a cardiomyocyte model.

Early Afterdepolarizations (EADs) are abnormal behaviors that can lead to cardiac failure and even cardiac death. In this paper we investigate the occurrence and development of these phenomena in a reduced Luo-Rudy cardiac model. Through a comprehensive dynamical analysis, we map out the distinct patterns observed in the parametric plane, differentiating between normal beats without EADs and pathological beats with EADs. By examining the bifurcation structure of the model, we elucidate the dynamical elements associated with these patterns and their transitions. Using a fast-slow analysis, we explore the emergence and evolution of EADs in the model. Notably, our approach combines the two commonly used fast-slow approaches (1-slow-2-fast and 2-slow-1-fast), and we show how both approaches together provide a more complete understanding of this phenomenon.

[HHV-8 Related immunological and hematological diseases]. / Maladies immunologiques et hématologiques liées à HHV-8.

HHV-8 is an oncogenic Gammaherpesvirinae discovered in 1994 during the HIV pandemic. It is the causative agent of Kaposi's sarcoma, and is also associated with the occurrence of several aggressive B lymphoproliferative disorders. Most of them occur in an immunosuppression setting, usually due to HIV infection. Multicentric HHV8-associated Castleman's disease and KSHV Inflammatory Cytokine Syndrome (KICS) are primarily reactive entities with prominent systemic features. They illustrate the cytokinic storm induced by HHV-8 in its cell host. On the other hand, HHV-8 can drive proliferation and lymphomagenesis of its plasmablastic cell host, and is associated with a risk to develop aggressive lymphomas with plasmacytic differenciation. Primary effusion lymphoma usually localizes in body cavities and may affect other extra-nodal sites ; its prognostic is poor. Diffuse large B-cell lymphoma HHV-8, NOS affect more commonly nodes and blood and evolve from infected cell of HHV-8 associated Castleman disease. On the contrary, germinotropic lymphoproliferative disorders presents mainly as localized adenopathy with indolent course, and show polyclonality. Histology plays a key role in distinguishing these different entities and need expert reviewing, especially since they may be associated with each other. Besides lymphoproliferative disorders, HHV8 is associated with various hematological manifestations. The aim of this review is to provide an update on the presentation, diagnosis, and management of immunologic and hematologic complications associated with HHV-8.

Entropy and canonical ensemble of hybrid quantum classical systems.

In this work we generalize and combine Gibbs and von Neumann approaches to build, for the first time, a rigorous definition of entropy for hybrid quantum-classical systems. The resulting function coincides with the two cases above when the suitable limits are considered. Then, we apply the MaxEnt principle for this hybrid entropy function and obtain the natural candidate for the hybrid canonical ensemble (HCE). We prove that the suitable classical and quantum limits of the HCE coincide with the usual classical and quantum canonical ensembles since the whole scheme admits both limits, thus showing that the MaxEnt principle is applicable and consistent for hybrid systems.

[Peripheral T cell lymphomas: diagnosis and treatment]. / Lymphomes T périphériques : diagnostic et prise en charge.

Peripheral T cell lymphomas are rare malignancies with aggressive course, with several different subtype described in the 2016 WHO classification. Their distribution across the world is heterogenous, with marked difference between Western and Asian country. Their clinical presentation often comprise extra-nodal involvement, B symptoms and immune system disorder which can lead to wrong diagnosis orientation. Make a right diagnosis need a experienced pathologist in close collaboration with clinical datas. Peripheral T cell lymphomas are in general associated with poor prognosis when treated with anthracyclines-based regimen, and several studies and trials focused on the use of intensified regimen or novel targeted agents, whose proper indication still remain to be clarified.

Ehrenfest Statistical Dynamics in Chemistry: Study of Decoherence Effects.

In previous works, we introduced a geometric route to define our Ehrenfest statistical dynamics (ESD) and we proved that, for a simple toy model, the resulting ESD does not preserve purity. We now take a step further: we investigate decoherence and pointer basis in the ESD model by considering some uncertainty in the degrees of freedom of a simple but realistic molecular model, consisting of two classical cores and one quantum electron. The Ehrenfest model is sometimes discarded as a valid approximation to nonadiabatic coupled quantum-classical dynamics because it does not describe the decoherence in the quantum subsystem. However, any rigorous statistical analysis of the Ehrenfest dynamics, such as the described ESD formalism, proves that decoherence exists. In this article, decoherence in ESD is studied by measuring the change in the quantum subsystem purity and by analyzing the appearance of the pointer basis to which the system decoheres, which for our example is composed of the eigenstates of the electronic Hamiltonian.

Liver fibrosis staging with contrast-enhanced ultrasonography: prospective multicenter study compared with METAVIR scoring.

We prospectively assessed contrast-enhanced sonography for evaluating the degree of liver fibrosis as diagnosed via biopsy in 99 patients. The transit time of microbubbles between the portal and hepatic veins was calculated from the difference between the arrival time of the microbubbles in each vein. Liver biopsy was obtained for each patient within 6 months of the contrast-enhanced sonography. Histological fibrosis was categorized into two classes: (1) no or moderate fibrosis (F0, F1, and F2 according to the METAVIR staging) or (2) severe fibrosis (F3 and F4). At a cutoff of 13 s for the transit time, the diagnosis of severe fibrosis was made with a specificity of 78.57%, a sensitivity of 78.95%, a positive predictive value of 78.33%, a negative predictive value of 83.33%, and a performance accuracy of 78.79%. Therefore, contrast-enhanced ultrasound can help with differentiation between moderate and severe fibrosis.

[The role of echoendoscopic biopsy in diagnosing tuberculosis of pancreas]. / Tuberculose pancréatique: apport de la ponction sous échoendoscopie.

The diagnosis of an abdominal mass using imaging techniques is difficult for clinicians and radiologists. We report a case of an atypical peripancreatic mass, mimicking a carcinoma on abdominal computed tomography and which was only diagnosed after an echoendoscopic biopsy of the mass was performed. It is difficult to differentiate abdominal tuberculosis from a neoplasm, especially if there is no pulmonary tuberculosis. Usually, the diagnosis of abdominal tuberculosis is only confirmed histologically, after surgical resection of the mass. Echoendoscopic biopsy confirmed the infectious nature of the mass and prevented complicated and difficult surgery.

[Mammography in younger women: interpretation of abnormal findings]. / Mammographie de la femme jeune: comment interpréter une image anormale?

The aim of this paper is to report the mammographic predictive positive value by decade of age using the assessment categories described within the BI-RADS lexicon.

An Early Permian plant assemblage from the Taiyuan Formation of northern China with compression/impression and permineralized preservation.

A small but diverse fossil flora is described from the Early Permian Taiyuan Formation occurring at the Yangshuling mine in Pingquan district of Hebei Province, northern China. Fossils occur as compression/impressions within mudrocks and fine-grained sandstones and also as carbonate permineralizations within volcaniclastic tuffs. All are fragmentary and contain lycopsids, sphenopsids, ferns and seed plants, and include several new species. In the compression assemblage sphenopsid and pteridosperm foliage accounts for the majority of the fossils recognised with only a few other kinds of plant organs present. In contrast, the permineralized assemblage is dominated by cordaitaleans with a composition similar to that occurring in coal-ball assemblages elsewhere in the Taiyuan Formation. From the taxonomic synthesis presented it is apparent that the Yangshuling permineralized assemblage contains many of the plant taxa diagnostic of the northern realm of the Early Permian Cathaysian flora, and preserves a representative sample of the wetland coal-swamp vegetation of this time. The permineralized assemblage at Yangshuling represents the first example of anatomically preserved plants from volcaniclastic lithologies from the Palaeozoic of China, raising the possibility of similarly preserved plant-fossil assemblages elsewhere in the Cathaysian realm.

How early ferns became trees.

A new anatomically preserved fern, discovered from the basalmost Carboniferous of Australia, shows a unique combination of very primitive anatomical characters (solid centrarch cauline protostele) with the elaboration of an original model of the arborescent habit. This plant possessed a false trunk composed of a repetitive branching system of very small stems, which established it as the oldest tree-fern known to date. The potential of this primitive zygopterid fern to produce such an unusual growth form-without real equivalent among living plants-is related to the possession of two kinds of roots that have complementary functional roles: (i) large roots produced by stems with immediate positive geotropism, strongly adapted to mechanical support and water uptake from the soil; and (ii) small roots borne either on large roots or on petiole bases for absorbing humidity inside the false trunk.

Structure and Development of Sphenophyllum oblongifolium from the Upper Carboniferous of France.

Variation in branching pattern and leaf morphology in Sphenophyllum oblongifolium are investigated based on new compression material from the Upper Carboniferous (Stephanian) of France. Morphometric analysis reveals correlation between several parameters (internodal length, maximum diameter of axis, leaf length). Ontogenetic variability of axis diameter and internodal length is also demonstrated. There is no evidence of a rhythmic elongation of stems, which are interpreted as axes with a determinate but continuous growth. The vegetative system of S. oblongifolium is composed of four to five successive orders of axes. Branching is intermittent and diffuse, with an aleatory distribution of proleptic branches in which internode length may equal that in the parent stem. In the slender axes of the vegetative system of S. oblongifolium there is no clear hierarchy among successive orders of axes. This contrasts with the situation in the calamitean sphenopsids, where the successive orders of axes show distinct differences in diameter. Heterophylly of S. oblongifolium is documented in detail. As in some other species (e.g., Sphenophyllum emarginatum), heterophylly is interpreted partly as an adaptation to a more or less scrambling habit.

[Acardiac acephalic fetus and twin pregnancy. Report of a case]. / Foetus acardiaque acéphale et grossesse gémellaire. A propos d'un cas.

The present case describes an acardiac, acephalic fetus, diagnosed by ultra-sound, during the 33rd gestational week of an insulin dependent diabetic parturient, who had developed toxemia gravida. The diagnosis had been confirmed by the autopsy. The differential diagnosis from an in-utero death of the second twin had been raised. The acardiac acephalic foetus is a rare congenital malformation observed during the monozygotic twin pregnancy. The second fetus being normal, our approach consisted in the clinical observation of the parturient, followed by cesarean section delivery the 4th day of the 36th gestational week to avoid worsening of toxemia gravida.

Molecules and morphology: conflicts and congruence within the fern genus Trichomanes (Hymenophyllaceae).

The interaction between three independent data sets (anatomy/morphology, cytology, molecules) has been evaluated within the controversial genus Trichomanes (Hymenophyllaceae). Anatomy/morphology, cytology, and rbcL sequences, despite their high and significant level of incongruence, were thus empirically combined with differential weighting in a cladistic analysis within Trichomanes in order to give an appreciation of the contribution of each data set in the resulting topologies and to study more precisely the nature of potential conflicts. Results show that any standard statistics values (such as bootstrap) do not appear to be objectively useful for the choice of the "best" topology or the "good" clades provided by the combination. This weighting approach reveals three cases: (i) some clades (such as subgenus Didymoglossum) are always retrieved and correspond to the absence of conflicts between the different data, (ii) some new clades (such as subgenus Achomanes) are either provided or reenforced as a "synergetic" result of the combination of the data and (iii) that remaining conflicting clades reflect the persistence of incongruence between data whatever the weighting.

[Leptospirosis in Mayotte]. / La leptospirose à Mayotte.

We have got 42 leptospirosis cases from 1984 to 1989, in a retrospective study. The annual incidence is now, in a very high level (3.8/10,000 pers.). This rapid increasing is function of new diagnostics facilities. The leptospirosis epidemiology is not different from anywhere else in tropical countries, but the complicated cases are an important problem in public health in the island. The actual development of collective hygienic equipment is indispensable for any progress.

[Seroepidemiologic evaluation of malaria in Mayotte (Comoro archipelago) 1984-1988]. / Evaluation séroépidémilogique du paludisme à Mayotte (archipel des Comores) 1984-1988.

In the context of a research programme on the immunology of malaria in the islands of the south-west of the Indian Ocean, seroepidemiological studies by means of sampling surveys have been carried out annually in Mayotte Island (Comoro Archipelago) from 1984 to 1988. Apart from the transient character of the increases in rates in the wake of the epidemic outbreak of 1984, the evolution of the antibody geometric mean reciprocal titre (GMRT) by age reveals a negativation of population at large, fast only in the younger age-group. At such a high level of negativation, the GMRT does not lend itself to interpretation. In the older age-groups the negativation becomes so slow as to render a yearly periodicity too short to show differences. The correlation between GMRT and age that persisted over the five-year period suggests that the evolution of the rates according to age follows a predetermined model. The epidemiological interpretation of purely serological data, except for a general indication of the trend, is however difficult, specially in an archipelago where the levels of malaria transmission are not the same in the different islands, but where inter-island migration is quite important.