Les populations néoteniques de Triturus helveticus des causses et du Bas-Languedoc I. Répartition et caractéristiques

Neoteny is common in some populations of Palmate newts Triturus helveticus of Southern France. Population samples have been collected from 117 pools, at three different seasons of the year. Percentages of neotenic individuals have been calculated for 29 of these pools where neotenic newts were found. Neoteny is not evenly distributed over the whole study area. It is more prevalent in the S.E. part of the Causse du Larzac and in the Causse de Blandas, than in the coastal plains of Languedoc. On the “ causses ” (arid limestone tablelands), neoteny only occurs among palmate newts, no neotenic individual having ever been found among the sympatric Triturus marmoratus population. Morphological differences between neotenic and normal popu lations of Triturus helveticus are described. None of them is consistent enough to allow sub-specific status to be given to the neotenic population. Breeding takes place later in the season among the Larzac population and the duration of the aquatic phase of the yearly cycle is also longer in the plateau population than among the newts of the coastal plains. All these differences, morphological as well as biological, disappear when the newts are kept in labo ratory conditions. Metamorphosis occurs normally when the progeny of both newt populations are bred in the laboratory. However mortality is much higher among the progeny of neotenic females, during their first three months of life

Les populations néoténiques de Triturus helveticus Raz. des Causses et du Bas-Languedoc. II. Ecologie

The physical, chemical, and biotic characteristics of the ponds where neotenic populations of Palmate newts are found in Sou thern France are described. The frequency of neoteny is high in permanent ponds, at an altitude ranging from 400 to 700 m, on arid limestone plateaux with a yearly rainfall of 1500-2000 mm. In such areas there are large seasonal variations of water temperature, ranging from + 1 to + 28 °C, water remaining cold (below + 15°C) for 8 to 10 months during the year. The saline content of water is low, as shown by conductivity figures (less than 200 pmhos/cm/cm2) . No iodine deficiency was ever found in the ponds of the study area. A correlation has been found between the frequency of neoteny and the water concentration in Ca, Mg and particularly K (which may account for 35-40 % of the cations) . The aridity of the area surrounding the pools can also contri bute to the selection of neotenic individuals, paedogenesis being of obvious adaptive value in such an environment

Predicting the prices of cards in the game Magic with machine learning

V tem diplomskem delu smo preučevali trende gibanja cen pri kartah igre Magic: The Gathering in pri tem uporabili najbolj primerne metode strojnega ućenja. Cilj je bil izdelati napovedni model za cene kart. Naša naloga je bila identiciranje pomembnih virov, pridobivanje potrebnih podatkov, njihova pretvorba v računalniku razumljivo obliko ter izbira primernega algoritma. Model, ki smo ga ustvarili, se je izkazal za zanesljivega s 61% točnostjo napovedi gibanja cene pri zelo redkih kartah, medtem ko smo pri redkih kartah dosegli le 52% točnost, kar ni preseglo niti privzete točnosti. Pri nalogi smo uporabili metodo podpornih vektorjev ter si pomagali z orodjem Weka. S podatki, ki smo jih pridobili, smo naredili še nekaj poizkusov in tako poiskali nekaj novih odvisnosti med podatki, ki jih prej nismo poznali.This thesis is a study of Magic: The Gathering card price fluctuations using the most appropriate machine learning methods. The goal was to construct a predictive model for card prices. This required us to identify crucial attributes, gather necessary data, convert it to a machine-readable format and select a suitable learning algorithm for the task. The resulting model was effective, attaining a 61 % price trend accuracy with mythic rare cards, while it was less successful with rare cards with only 52% accuracy, which failed to beat default accuracy. Support vector machines algorithms and the machine learning toolbox Weka were used to achieve these results, which were applied in further experiments that led to the discovery of previously unknown data dependencies

Severe hematopoietic stem cell inflammation compromises chronic granulomatous disease gene therapy

X-linked chronic granulomatous disease (CGD) is associated with defective phagocytosis, life-threatening infections, and inflammatory complications. We performed a clinical trial of lentivirus-based gene therapy in four patients (NCT02757911). Two patients show stable engraftment and clinical benefits, whereas the other two have progressively lost gene-corrected cells. Single-cell transcriptomic analysis reveals a significantly lower frequency of hematopoietic stem cells (HSCs) in CGD patients, especially in the two patients with defective engraftment. These two present a profound change in HSC status, a high interferon score, and elevated myeloid progenitor frequency. We use elastic-net logistic regression to identify a set of 51 interferon genes and transcription factors that predict the failure of HSC engraftment. In one patient, an aberrant HSC state with elevated CEBPβ expression drives HSC exhaustion, as demonstrated by low repopulation in a xenotransplantation model. Targeted treatments to protect HSCs, coupled to targeted gene expression screening, might improve clinical outcomes in CGD

Simulated Microgravity Compromises Mouse Oocyte Maturation by Disrupting Meiotic Spindle Organization and Inducing Cytoplasmic Blebbing

In the present study, we discovered that mouse oocyte maturation was inhibited by simulated microgravity via disturbing spindle organization. We cultured mouse oocytes under microgravity condition simulated by NASA's rotary cell culture system, examined the maturation rate and observed the spindle morphology (organization of cytoskeleton) during the mouse oocytes meiotic maturation. While the rate of germinal vesicle breakdown did not differ between 1 g gravity and simulated microgravity, rate of oocyte maturation decreased significantly in simulated microgravity. The rate of maturation was 8.94% in simulated microgravity and was 73.0% in 1 g gravity. The results show that the maturation of mouse oocytes in vitro was inhibited by the simulated microgravity. The spindle morphology observation shows that the microtubules and chromosomes can not form a complete spindle during oocyte meiotic maturation under simulated microgravity. And the disorder of γ-tubulin may partially result in disorganization of microtubules under simulated microgravity. These observations suggest that the meiotic spindle organization is gravity dependent. Although the spindle organization was disrupted by simulated microgravity, the function and organization of microfilaments were not pronouncedly affected by simulated microgravity. And we found that simulated microgravity induced oocytes cytoplasmic blebbing via an unknown mechanism. Transmission electron microscope detection showed that the components of the blebs were identified with the cytoplasm. Collectively, these results indicated that the simulated microgravity inhibits mouse oocyte maturation via disturbing spindle organization and inducing cytoplasmic blebbing

MCT Expression and Lactate Influx/Efflux in Tanycytes Involved in Glia-Neuron Metabolic Interaction

Metabolic interaction via lactate between glial cells and neurons has been proposed as one of the mechanisms involved in hypothalamic glucosensing. We have postulated that hypothalamic glial cells, also known as tanycytes, produce lactate by glycolytic metabolism of glucose. Transfer of lactate to neighboring neurons stimulates ATP synthesis and thus contributes to their activation. Because destruction of third ventricle (III-V) tanycytes is sufficient to alter blood glucose levels and food intake in rats, it is hypothesized that tanycytes are involved in the hypothalamic glucose sensing mechanism. Here, we demonstrate the presence and function of monocarboxylate transporters (MCTs) in tanycytes. Specifically, MCT1 and MCT4 expression as well as their distribution were analyzed in Sprague Dawley rat brain, and we demonstrate that both transporters are expressed in tanycytes. Using primary tanycyte cultures, kinetic analyses and sensitivity to inhibitors were undertaken to confirm that MCT1 and MCT4 were functional for lactate influx. Additionally, physiological concentrations of glucose induced lactate efflux in cultured tanycytes, which was inhibited by classical MCT inhibitors. Because the expression of both MCT1 and MCT4 has been linked to lactate efflux, we propose that tanycytes participate in glucose sensing based on a metabolic interaction with neurons of the arcuate nucleus, which are stimulated by lactate released from MCT1 and MCT4-expressing tanycytes