577 research outputs found

    Insulin-like growth factor 1 and growth seasonality in reindeer (Rangifer tarandus) - comparisons with temperate and tropical cervids

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    Growth in temperate and arctic deer is seasonal, with higher growth rates in spring and summer while growth rates are low or negative in autumn and winter. We have measured IGF1 concentrations in the plasma of reindeer calves exposed to a manipulated photoperiod, indoors, of either 16 hours light followed by 8 hours dark each day (16L:8D) (n = 3) or 8L:16D (n = 3) from about the autumnal to the vernal equinox, to determine whether the seasonal growth spurt normally seen in spring is associated with changes in the circulating level of IGF1. A high quality concentrate diet was available ad libitum. The animals were weighed, and bled every 2 weeks and plasma samples assayed for IGF1 by radioimmunoassay. 6-8 weeks after the start of the study those calves exposed to 16L.-8D showed a significant increase in plasma IGF1 concentration which was maintained until the close of the experiment, 24 weeks after the start. In contrast IGF1 plasma concentrations in those calves exposed to a daylength of 8L:16D did not significantly alter during the study. The elevated IFG1 in the 16L:8D group was associated with rapid weight gain compared with the 8L:16D group. We have shown that the seasonal growth spurt is preceded by an elevation in plasma IFG1 concentration. Further, this elevation in IGF1 is daylength dependent. For comparison IGF1 and growth rate seasonal profiles from temperate and tropical deer are included. This comparison reveals that seasonal increases in IGF1 take place only in animals with a seasonal growth spurt. Thus IGF1 plasma level elevations seem most closely associated with the resumption of rapid growth in spring following the winter

    Locomotor hyperactivity in 14-3-3Zeta KO mice is associated with dopamine transporter dysfunction

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    Dopamine (DA) neurotransmission requires a complex series of enzymatic reactions that are tightly linked to catecholamine exocytosis and receptor interactions on pre- and postsynaptic neurons. Regulation of dopaminergic signalling is primarily achieved through reuptake of extracellular DA by the DA transporter (DAT) on presynaptic neurons. Aberrant regulation of DA signalling, and in particular hyperactivation, has been proposed as a key insult in the presentation of schizophrenia and related neuropsychiatric disorders. We recently identified 14-3-3ΞΆ as an essential component of neurodevelopment and a central risk factor in the schizophrenia protein interaction network. Our analysis of 14-3-3ΞΆ-deficient mice now shows that baseline hyperactivity of knockout (KO) mice is rescued by the antipsychotic drug clozapine. 14-3-3ΞΆ KO mice displayed enhanced locomotor hyperactivity induced by the DA releaser amphetamine. Consistent with 14-3-3ΞΆ having a role in DA signalling, we found increased levels of DA in the striatum of 14-3-3ΞΆ KO mice. Although 14-3-3ΞΆ is proposed to modulate activity of the rate-limiting DA biosynthesis enzyme, tyrosine hydroxylase (TH), we were unable to identify any differences in total TH levels, TH localization or TH activation in 14-3-3ΞΆ KO mice. Rather, our analysis identified significantly reduced levels of DAT in the absence of notable differences in RNA or protein levels of DA receptors D1–D5. Providing insight into the mechanisms by which 14-3-3ΞΆ controls DAT stability, we found a physical association between 14-3-3ΞΆ and DAT by co-immunoprecipitation. Taken together, our results identify a novel role for 14-3-3ΞΆ in DA neurotransmission and provide support to the hyperdopaminergic basis of pathologies associated with schizophrenia and related disorders.H Ramshaw, X Xu, EJ Jaehne, P McCarthy, Z Greenberg, E Saleh, B McClure, J Woodcock, S Kabbara, S Wiszniak, Ting-Yi Wang, C Parish, M van den Buuse, BT Baune, A Lopez and Q Schwar

    Contribution of Cystine-Glutamate Antiporters to the Psychotomimetic Effects of Phencyclidine

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    Altered glutamate signaling contributes to a myriad of neural disorders, including schizophrenia. While synaptic levels are intensely studied, nonvesicular release mechanisms, including cystine–glutamate exchange, maintain high steady-state glutamate levels in the extrasynaptic space. The existence of extrasynaptic receptors, including metabotropic group II glutamate receptors (mGluR), pose nonvesicular release mechanisms as unrecognized targets capable of contributing to pathological glutamate signaling. We tested the hypothesis that activation of cystine–glutamate antiporters using the cysteine prodrug N-acetylcysteine would blunt psychotomimetic effects in the rodent phencyclidine (PCP) model of schizophrenia. First, we demonstrate that PCP elevates extracellular glutamate in the prefrontal cortex, an effect that is blocked by N-acetylcysteine pretreatment. To determine the relevance of the above finding, we assessed social interaction and found that N-acetylcysteine reverses social withdrawal produced by repeated PCP. In a separate paradigm, acute PCP resulted in working memory deficits assessed using a discrete trial t-maze task, and this effect was also reversed by N-acetylcysteine pretreatment. The capacity of N-acetylcysteine to restore working memory was blocked by infusion of the cystine–glutamate antiporter inhibitor (S)-4-carboxyphenylglycine into the prefrontal cortex or systemic administration of the group II mGluR antagonist LY341495 indicating that the effects of N-acetylcysteine requires cystine–glutamate exchange and group II mGluR activation. Finally, protein levels from postmortem tissue obtained from schizophrenic patients revealed significant changes in the level of xCT, the active subunit for cystine–glutamate exchange, in the dorsolateral prefrontal cortex. These data advance cystine–glutamate antiporters as novel targets capable of reversing the psychotomimetic effects of PCP

    The Large Enriched Germanium Experiment for Neutrinoless Double Beta Decay (LEGEND)

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    The observation of neutrinoless double-beta decay (0Ξ½Ξ²Ξ²{\nu}{\beta}{\beta}) would show that lepton number is violated, reveal that neutrinos are Majorana particles, and provide information on neutrino mass. A discovery-capable experiment covering the inverted ordering region, with effective Majorana neutrino masses of 15 - 50 meV, will require a tonne-scale experiment with excellent energy resolution and extremely low backgrounds, at the level of ∼\sim0.1 count /(FWHMβ‹…\cdottβ‹…\cdotyr) in the region of the signal. The current generation 76^{76}Ge experiments GERDA and the MAJORANA DEMONSTRATOR utilizing high purity Germanium detectors with an intrinsic energy resolution of 0.12%, have achieved the lowest backgrounds by over an order of magnitude in the 0Ξ½Ξ²Ξ²{\nu}{\beta}{\beta} signal region of all 0Ξ½Ξ²Ξ²{\nu}{\beta}{\beta} experiments. Building on this success, the LEGEND collaboration has been formed to pursue a tonne-scale 76^{76}Ge experiment. The collaboration aims to develop a phased 0Ξ½Ξ²Ξ²{\nu}{\beta}{\beta} experimental program with discovery potential at a half-life approaching or at 102810^{28} years, using existing resources as appropriate to expedite physics results.Comment: Proceedings of the MEDEX'17 meeting (Prague, May 29 - June 2, 2017

    The Transcriptional Regulator Rok Binds A+T-Rich DNA and Is Involved in Repression of a Mobile Genetic Element in Bacillus subtilis

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    The rok gene of Bacillus subtilis was identified as a negative regulator of competence development. It also controls expression of several genes not related to competence. We found that Rok binds to extended regions of the B. subtilis genome. These regions are characterized by a high A+T content and are known or believed to have been acquired by horizontal gene transfer. Some of the Rok binding regions are in known mobile genetic elements. A deletion of rok resulted in higher excision of one such element, ICEBs1, a conjugative transposon found integrated in the B. subtilis genome. When expressed in the Gram negative E. coli, Rok also associated with A+T-rich DNA and a conserved C-terminal region of Rok contributed to this association. Together with previous work, our findings indicate that Rok is a nucleoid associated protein that serves to help repress expression of A+T-rich genes, many of which appear to have been acquired by horizontal gene transfer. In these ways, Rok appears to be functionally analogous to H-NS, a nucleoid associated protein found in Gram negative bacteria and Lsr2 of high G+C Mycobacteria

    Primary mucinous carcinoma of the skin: a case of metastasis after 10Β years of disease-free interval

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    Primary mucinous carcinoma of the skin (MCS) is a rare neoplasm. Clinically, it has a high local recurrence rate, but it is known to be a slow-growing benign tumor with a rare incidence of distant metastases. We present a case of primary MCS on the jaw that underwent tumor resection twice and was disease-free for 10Β years after the second surgery. The patient had no evidence of local recurrence and distant metastasis until his 11th year follow-up. At that time, he was diagnosed with lung and bone metastasis and died 3Β years after this. To our knowledge, this is the first case of MCS that presented with metastasis with more than 10-year disease-free interval. Since MCS is a slow-growing asymptomatic tumor, distant metastasis is difficult to diagnose without detailed radiological examination. We believe that computed tomography and resonance imaging should be performed for early diagnosis of metastasis even for cases with long-term disease-free interval, especially cases of local recurrence

    Longitudinal study on birthweight and the incidence of endometrial cancer

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    From 1976 to 2004, we followed 71 751 participants of the Nurses' Health Study and identified 676 invasive endometrial cancer cases. Birthweight, assessed in 1992, was not associated with the incidence of endometrial cancer. No effect modification by menopausal status was observed, but statistical power to detect an interaction was limited

    Randomized, double-blind trial of olanzapine versus placebo in patients prodromally symptomatic for psychosis

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    Objective: This study assessed the efficacy of olanzapine in delaying or preventing conversion to psychosis and reducing symptoms in people with prodromal symptoms of schizophrenia. Method: This randomized trial occurred at four North American clinics in the Prevention Through Risk Identification, Management, and Education project. Outpatients received olanzapine (5–15 mg/day, N=31) or placebo (N=29) during a 1-year double-blind treatment period and no treatment during a 1-year follow-up period. Efficacy measures included the conversion-to-psychosis rate and Scale of Prodromal Symptoms scores. Results: During the treatment year, 16.1% of olanzapine patients and 37.9% of placebo patients experienced a conversion to psychosis, a nearly significant difference. The hazard of conversion among placebo patients was about 2.5 times that among olanzapine-treated patients, which also approached significance. In the follow-up year, the conversion rate did not differ significantly between groups. During treatment, the mean score for prodromal positive symptoms improved more in the olanzapine group than in the placebo group, and the mixed-model repeated-measures least-squares mean score showed significantly greater improvement between weeks 8 and 28 with olanzapine. The olanzapine patients gained significantly more weight (mean=8.79 kg, SD=9.05, versus mean=0.30 kg, SD=4.24). Conclusions: A significant treatment difference in the conversion-to-psychosis rate was not demonstrated. However, these results may be influenced by low power. The nearly significant differences suggest that olanzapine might reduce the conversion rate and delay onset of psychosis. Olanzapine was efficacious for positive prodromal symptoms but induced weight gain. Further treatment research in this phase of illness is warrante

    Effect of Mouth Rinsing and Ingestion of Carbohydrate Solutions on Mood and Perceptual Responses During Exercise

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    Background: The aim of this study was to investigate whether mouth rinsing or ingesting carbohydrate (CHO) solutions impact on perceptual responses during exercise. Methods: Nine moderately trained male cyclists underwent a 90-min glycogen-reducing exercise, and consumed a low CHO meal, prior to completing an overnight fast. A 1-h cycle time trial was performed the following morning. Four trials, each separated by 7days, were conducted in a randomized, counterbalanced study design: 15% CHO mouth rinse (CHOR), 7.5% CHO ingestion (CHOI), placebo mouth rinse (PLAR) and placebo ingestion (PLAI). Solution volumes (1.5mlΒ·g-1 ingestion trials and 0.33mlΒ·kg-1 rinsing trials) were provided after every 12.5% of completed exercise. Perceptual scales were used to assess affective valence (feeling scale, FS), arousal (felt arousal scale, FAS), exertion (ratings of perceived exertion, RPE) and mood (profile of mood states, POMS) before, during and immediately after exercise. Results: There was no difference in RPE (CHOI, 14.0Β±9; CHOR, 14.2Β±.7; PLAI, 14.6Β±1.8; PLAR, 14.6Β±2.0; P=0.35), FS (CHOI, 0.0Β±1.7; CHOR, -0.2Β±1.5; PLAI, -0.8Β±1.4; PLAR, -0.8Β±1.6; P0.15), or FAS (CHOI, 3.6Β±1.1; CHOR, 3.5Β±1.0; PLAI, 3.4Β±1.4; PLAR, 3.3Β±1.3; P=725) scores between trials. While overall POMS score did not appear to differ between trials, the 'vigour' subscale indicated that CHOI may facilitate the maintenance of 'vigour' scores over time, in comparison to the steady decline witnessed in other trials (P=0.04). There was no difference in time trial performance between trials (CHOI, 65.3Β±4.8min; CHOR, 68.4Β±3.9min; PLAI, 68.7Β±5.3min; PLAR, 68.3Β±5.2min; P=0.21) but power output was higher in CHOI (231.0Β±33.2 W) relative to other trials (221-223.6 W; Plt0.01). Conclusions: In a CHO-reduced state, mouth rinsing with a CHO solution did not impact on perceptual responses during high-intensity exercise in trained cyclists and triathletes. On the other hand CHO ingestion improved perceived ratings of vigour and increased power output during exercise
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