122 research outputs found

    Laterality of a second player position affects lateral deviation of basketball shooting

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    Asymmetrically placed visual distractors are known to cause a lateral bias in the execution of a movement directed toward a target. The aim of the present experiment was to verify if the trajectory of the ball and the trajectory of the jump for a basketshot can be affected by the sole position of a second player, who stays in front of the shooting player in one of three possible positions (centre, left or right) but too far to physically interfere with the shot. Young basketball players were asked to perform 60 shots at 6.25 m from a regular basket, with or without a second player staying in front of them in, alternately, a centre, left or right position. A computerised system measured the angular deviation of the jump direction from the vertical direction and the lateral deviation of the ball trajectory from the midline. The results showed that both the jump direction and the entry position of the ball deviated toward the opposite side from the second player’s side; however, these effects were too small to significantly affect the mean goal percentage. This result confirms that some placements of the players can have an effect as visual distractors. Further studies are necessary to find what game conditions can make such distractors harmful for the athletic performance

    Alterações comportamentais e na memória de Mus musculus coinfectado por Toxocara canis e Toxoplasma gondii

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    Several researchers have stated that parasites can alter the behavior of their hosts, in order to increase the transmission rate, principally when prey-predator relationships are a reliable way of infection transmission. The aim of this study was to verify the occurrence of changes in anxiety and short-term memory patterns in experimentally infected Mus musculus by Toxocara canis and/or Toxoplasma gondii. Forty male Mus musculus (Balb/c) eight-week-old were divided into four groups of 10 mice each. One group was infected with 300 eggs of Toxocara canis; a second group was submitted to infection with 10 cysts of Toxoplasma gondii; a third group was concomitantly infected with both parasites with the same inoculums and the last group was maintained without infection. The anxiety levels were evaluated using an elevated plus maze and an actometer; the short-term memory was determined by a two-way active avoidance equipment. The determination of anxiety levels were conducted 40 and 70 days after infection and the short-term memory was evaluated 140 days after infection. Mice chronically infected by Toxoplasma gondii showed impaired learning and short-term memory, but no significant differences were found in mice infected by Toxocara canis or concomitantly infected by Toxocara canis and Toxoplasma gondii when compared to non infected mice.Pesquisadores afirmam que parasitos podem alterar o comportamento de seus hospedeiros a fim de aumentar a sua taxa de transmissão. O objetivo deste estudo foi verificar a ocorrência de alterações na ansiedade e padrões de memória de curta duração em Mus musculus experimentalmente infectados por Toxocara canis e/ou Toxoplasma gondii. Utilizaram-se 40 camundongos da espécie Mus musculus machos (Balb/c) com oito semanas de idade, divididos em quatro grupos de 10 ratos cada. Um grupo foi infectado com 300 ovos de Toxocara canis, um segundo grupo foi submetido à infecção com 10 cistos de T. gondii, um terceiro grupo foi infectado concomitantemente com ambos os parasitas e o último grupo foi mantido sem infecção. Os níveis de ansiedade foram avaliados por meio de labirinto em cruz elevado e actômetro, a memória de curta duração foi determinada por esquiva aversiva. A determinação dos níveis de ansiedade foi realizada 40 e 70 dias após infecção e a memória de curto prazo foi avaliada 140 dias após a infecção. Camundongos cronicamente infectados por Toxoplasma gondii mostraram deficiência de aprendizagem e memória de curto prazo, mas não foram encontradas diferenças significantes em camundongos infectados por Toxocara canis ou concomitantemente infectados por Toxocara canis e Toxoplasma gondii quando comparados com camundongos não infectados

    Eficácia da nitazoxanida contra Toxocara canis: recuperação larvária e resposta imune humoral em camundongos experimentalmente infectados

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    Foi investigada a eficácia da nitazoxanida (NTZ) na toxocaríase murina experimental e os resultados comparados com os obtidos usando mebendazol (MBZ). Sessenta camundongos BALB/c machos, com idade entre seis e oito semanas foram divididos em grupos de 10 cada, 50 foram infectados oralmente com 300 ovos larvados de T. canise agrupados a seguir: GI: camundongos infectados não tratados; GII: camundongos infectados tratados com MBZ (15 mg/kg/dia) 10 dias pós-infecção (dpi); GIII: camundongos infectados tratados com NTZ (20 mg/kg/dia) 10 dpi, GIV: camundongos infectados tratados com MBZ 60 dpi; GV: camundongos infectados tratados com NTZ 60 dpi; GVI: controle não infectado. Os camundongos foram sangrados via plexo retro orbitário em quatro ocasiões entre o 30º e 120º dpi. Os soros foram processados pela técnica de ELISA para detecção de anticorpos IgG anti- Toxocara.Aos 120 dpi, os animais foram sacrificados para a recuperação larvária do SNC, fígado, pulmões, rins, olhos e carcaça. Os resultados mostraram níveis similares de anticorpos IgG anti- Toxocaraentre os camundongos infectados mas não submetidos a tratamento e os grupos infectados e tratados com MBZ ou NTZ, aos 10 e 60 dpi. Os valores da recuperação larval foram similares nos grupos tratados com NTZ e MBZ 10 dpi. MBZ mostrou melhor eficácia aos 60 dpi, com redução de 72,6% da carga parasitária comparada com NTZ, que mostrou redução somente de 46,5%. Concluímos que a administração destes anti-helmínticos não modificou a resposta humoral na infecção experimental por T. canis. Não foi observada cura parasitológica com nenhuma das drogas; porém maior redução na carga parasitária foi obtida após o tratamento com MBZ.The efficacy of nitazoxanide (NTZ) against toxocariasis was investigated in an experimental murine model and results were compared to those obtained using mebendazole. Sixty male BALB/c mice, aged six to eight weeks-old, were divided into groups of 10 each; fifty were orally infected with 300 larvaed eggs of T. canisand grouped as follows, G I: infected untreated mice; G II: infected mice treated with MBZ (15 mg/kg/day) 10 days postinfection (dpi); G III: infected mice treated with NTZ (20 mg/kg/day) 10 dpi; G IV: infected mice treated with MBZ 60 dpi; G V: infected mice treated with NTZ 60 dpi; GVI: control group comprising uninfected mice. Mice were bled via retro-orbital plexus on four occasions between 30 and 120 dpi. Sera were processed using the ELISA technique to detect IgG anti- Toxocaraantibodies. At 120 dpi, mice were sacrificed for larval recovery in the CNS, liver, lungs, kidneys, eyes and carcass. Results showed similar levels of anti- ToxocaraIgG antibodies among mice infected but not submitted to treatment and groups treated with MBZ or NTZ, 10 and 60 dpi. Larval recovery showed similar values in groups treated with NTZ and MBZ 10 dpi. MBZ showed better efficacy 60 dpi, with a 72.6% reduction in the parasite load compared with NTZ, which showed only 46.5% reduction. We conclude that administration of these anthelmintics did not modify the humoral response in experimental infection by T. canis. No parasitological cure was observed with either drug; however, a greater reduction in parasite load was achieved following treatment with MBZ

    RUTAS DE MIGRACIÓN DE TOXOCARA CANIS Y TOCARA CATI EN LOS TEJIDOS DE\ud RATTUS NORVEGICUS INFECTADOS EXPERIMENTALMENTE

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    Toxocariasis is currently considered an important zoonosis in many countries and is usually attributed\ud to larvae of Toxocara canis Werner, 1782 but less frequently, T. cat. This study attempts to compare the\ud migration routes followed by T. canis and Toxocara cati (Schrank, 1788) in Rattus norvegicus\ud Berkenhout, 1769 and to determine the percentage of larvae recovered in each organ of experimentally\ud infected rats. Twenty-one 8-week-old, male specimens of R. norvegicus (Wistar) were inoculated\ud orally with 500 embryonated eggs of T. canis, while another 21 rats of the same species were\ud inoculated orally with 300 embryonated eggs of T. cati. On postinfection days 3, 5, 8, 10, 15, 30 and 60,\ud three rats from each group were sacrificed and larval recovery was performed from various organs and\ud the carcass following digestion with 0.5% HCl method. Comparisons of the percentage of recovered\ud larvae revealed that T. cati larvae migrated in greater quantities, as early as day 3 postinfection, to the\ud lungs (23.77%, compared to 0.34% for T. canis), while migration of T. cati larvae to the carcass was\ud observed from day 3 up to day 60 postinoculation. This experiment verified that the larvae of these two\ud species follow distinct migration routes and have different recovery rates.La toxocariasis es actualmente considerada una importante zoonosis en muchos países y es\ud generalmente atribuida a larvas de Toxocara canis (Werner, 1782, entretanto, a pesar de ser menos\ud frecuente, T. cati (Schrank, 1788) puede causar enfermedad. El objetivo de este estudio fue comparar\ud las rutas de migración seguidas por T. canis y T. cati en Rattus norvegicus (Berkenhout, 1769) y\ud determinar el porcentaje de larvas obtenidas en cada órgano de las ratas infectadas experimentalmente.\ud Veintiún especímenes machos de R. norvegicus (Wistar), con ocho semanas de edad fueron\ud inoculados oralmente con 500 huevos larvados de T. canis, en cuanto que otras 21 ratas de la misma\ud especie fueron inoculadas oralmente con 300 huevos embrionados de T. cati. En los días 3, 5, 8, 10, 15,\ud 30 y 60 pos-infección, tres ratas de cada grupo fueron sacrificadas y la recuperación de larvas fue\ud realizada en varios órganos y la musculatura después de la digestión con el método de HCl a 0,5%. La\ud comparación de los porcentajes de larvas recuperadas reveló que las larvas de T. cati migraron para los\ud pulmones en mayor cantidad, luego en el tercer día pos-infección (23,77%, y solamente 0,34% en el\ud caso de T. canis) al paso que la migración de larvas de T. cati para la musculatura fue observada desde\ud el día 3 hasta el día 60 pos-inoculación. Con este experimento se verificó que las larvas de estas dos\ud especies siguen rutas de migración distintas y tienen tasas de recuperación diferentes

    On the origin of the Galactic thin and thick discs, their abundance gradients and the diagnostic potential of their abundance ratios

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    Using a semi-analytical model of the evolution of the Milky Way, we show how secular evolution can create distinct overdensities in the phase space of various properties (e.g. age vs metallicity or abundance ratios vs age) corresponding to the thin and thick discs. In particular, we show how key properties of the Solar vicinity can be obtained by secular evolution, with no need for external or special events, like galaxy mergers or paucity in star formation. This concerns the long established double-branch behaviour of [alpha/Fe] vs metallicity and the recently found non-monotonic evolution of the stellar abundance gradient, evaluated at the birth radii of stars. We extend the discussion to other abundance ratios and we suggest a classification scheme, based on the nature of the corresponding yields (primary vs secondary or odd elements) and on the lifetimes of their sources (short-lived vs long-lived ones). The latter property is critical in determining the single- or double- branch behavior of an elementary abundance ratio in the Solar neighborhood. We underline the high diagnostic potential of this finding, which can help to separate clearly elements with sources evolving on different timescales and help determining the site of e.g. the r-process(es). We define the "abundance distance" between the thin and thick disc sequences as an important element for such a separation. We also show how the inside-out evolution of the Milky Way disc leads rather to a single-branch behavior in other disc regions.Comment: 20 pages, 16 figures, to appear in MNRA

    Effects of an high-fat diet enriched in lard or in fish oil on the hypothalamic amp-activated protein kinase and inflammatory mediators.

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    The high fat diet (HFD) rich in lard induces obesity, inflammation and oxidative stress, and the deregulation of hypothalamic nuclei plays an important role in this mechanism. One important factor involved in the food intake and inflammation is adenosine monophosphate-dependent kinase (AMPK), a serine/threonine kinase activated by phosphorylation. Omega (ω)3-polyunsaturated fatty acids (PUFA) are dietary compounds known to attenuate the obesity-related diseases, although the molecular mechanisms underlying their actions in the hypothalamus are not completely understood. We hypothesized that the beneficial effects of PUFA may be mediated by AMPK in the hypothalamus. To this aim, rats were fed a control diet (CD), or isocaloric HFD containing either fish oil (FD; rich in ω3-PUFA) or lard for 6 weeks, and the activation of AMPK, inflammatory state (IKKβ, TNF-α) and oxidative stress were analyzed in the hypothalamus. In addition, we also studied serum lipid profile, homeostatic model assessment (HOMA) index, and pro-inflammatory parameters. Our results showed, at the hypothalamic level of LD-fed rats, an increase of AMPK activation, inflammation and oxidative stress, while no modifications were detected in FD-fed animals compared to CD. In addition body weight gain, serum lipid profile, pro-inflammatory parameters and insulin resistance were reduced in FD animals compared to LD. In conclusion, our data indicate that the substitution of saturated by unsaturated fatty acids in the diet has beneficial effects on modulation of hypothalamic inflammation and function in obesity, underlying, at hypothalamic level, the interaction among insulin and/or leptin resistance, AMPK activation and hyperphagia

    Role of the orexin system on the hypothalamus-pituitary-thyroid axis

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    Hypocretin/orexin (ORX) are two hypothalamic neuropeptides discovered in 1998. Since their discovery, they have been one of the most studied neuropeptide systems because of their projecting fields innervating various brain areas. The orexinergic system is tied to sleep-wakefulness cycle, and narcolepsy is a consequence of their system hypofunction. Orexinergic system is also involved in many other autonomic functions such as feeding, thermoregulation, cardiovascular and neuroendocrine regulation. The main aim of this mini review article is to investigate the relationship between ORX and thyroid system regulation. Although knowledge about the ORX system is evolving, its putative effects on hypothalamic-pituitary-thyroid (HPT) axis still appear unclear. We analyzed some studies about ORX control of HPT axis to know better the relationship between them. The studies that were analyzed suggest Hypocretin/ORX to modulate the thyroid regulation, but the nature (excitatory or inhibitory) of this possible interaction remains actually unclear and needs to be confirmed

    Osteopontin: Relation between Adipose Tissue and Bone Homeostasis

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    Osteopontin (OPN) is a multifunctional protein mainly associated with bone metabolism and remodeling. Besides its physiological functions, OPN is implicated in the pathogenesis of a variety of disease states, such as obesity and osteoporosis. Importantly, during the last decades obesity and osteoporosis have become among the main threats to health worldwide. Because OPN is a protein principally expressed in cells with multifaceted effects on bone morphogenesis and remodeling and because it seems to be one of the most overexpressed genes in the adipose tissue of the obese contributing to osteoporosis, this mini review will highlight recent insights about relation between adipose tissue and bone homeostasis
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