905 resultados para Human-papillomavirus-16 E6
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Metabolic disruptions that occur widely in cancers offer an attractive focus for generalized treatment strategies. The hexosamine biosynthetic pathway (HBP) senses metabolic status and produces an essential substrate for O-linked β-N-acetylglucosamine transferase (OGT), which glycosylates and thereby modulates the function of its target proteins. Here, we report that the HBP is activated in prostate cancer cells and that OGT is a central regulator of c-Myc stability in this setting. HBP genes were overexpressed in human prostate cancers and androgen regulated in cultured human cancer cell lines. Immunohistochemical analysis of human specimens (n = 1987) established that OGT is upregulated at the protein level and that its expression correlates with high Gleason score, pT and pN stages, and biochemical recurrence. RNA interference-mediated siliencing or pharmacologic inhibition of OGT was sufficient to decrease prostate cancer cell growth. Microarray profiling showed that the principal effects of OGT inhibition in prostate cancer cells were related to cell-cycle progression and DNA replication. In particular, c-MYC was identified as a candidate upstream regulator of OGT target genes and OGT inhibition elicited a dose-dependent decrease in the levels of c-MYC protein but not c-MYC mRNA in cell lines. Supporting this relationship, expression of c-MYC and OGT was tightly correlated in human prostate cancer samples (n = 1306). Our findings identify HBP as a modulator of prostate cancer growth and c-MYC as a key target of OGT function in prostate cancer cells.
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Children with Prader-Willi syndrome often exhibit challenging behavior in response to changes to routine. This phenomenon has been linked to a deficit in task switching ability which has been observed in children with the syndrome. TASTER is a cognitive training game which is being designed with input from a group of children with Prader- Willi syndrome, which aims to train task switching ability and thus reduce associated challenging behavior.
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Accurately encoding the duration and temporal order of events is essential for survival and important to everyday activities, from holding conversations to driving in fast flowing traffic. Although there is a growing body of evidence that the timing of brief events (< 1s) is encoded by modality-specific mechanisms, it is not clear how such mechanisms register event duration. One approach gaining traction is a channel-based model; this envisages narrowly-tuned, overlapping timing mechanisms that respond preferentially to different durations. The channel-based model predicts that adapting to a given event duration will result in overestimating and underestimating the duration of longer and shorter events, respectively. We tested the model by having observers judge the duration of a brief (600ms) visual test stimulus following adaptation to longer (860ms) and shorter (340ms) stimulus durations. The channel-based model predicts perceived duration compression of the test stimulus in the former condition and perceived duration expansion in the latter condition. Duration compression occurred in both conditions, suggesting that the channel-based model does not adequately account for perceived duration of visual events.
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PURPOSE. Limited mechanistic understanding of diabetic retinopathy (DR) has hindered therapeutic advances. Berberine, an isoquinolone alkaloid, has shown favorable effects on glucose and lipid metabolism in animal and human studies, but effects on DR are unknown. We previously demonstrated intraretinal extravasation and modification of LDL in human diabetes, and toxicity of modified LDL to human retinal M¨uller cells. We now explore pathogenic effects of modified LDL on M¨uller cells, and the efficacy of berberine in mitigating this cytotoxicity. METHODS. Confluent human M¨uller cells were exposed to in vitro–modified ‘highly oxidized, glycated (HOG-) LDL versus native-LDL (N-LDL; 200 mg protein/L) for 6 or 24 hours, with/ without pretreatment with berberine (5 lM, 1 hour) and/or the adenosine monophosphate (AMP)-activated protein kinase (AMPK) inhibitor, Compound C (5 lM, 1 hour). Using techniques including Western blots, reactive oxygen species (ROS) detection assay, and quantitative real-time PCR, the following outcomes were assessed: cell viability (CCK-8 assay), autophagy (LC3, Beclin-1, ATG-5), apoptosis (cleaved caspase 3, cleaved poly-ADP ribose polymerase), oxidative stress (ROS, nuclear factor erythroid 2-related factor 2, glutathione peroxidase 1, NADPH oxidase 4), angiogenesis (VEGF, pigment epithelium-derived factor), inflammation (inducible nitric oxide synthase, intercellular adhesion molecule 1, IL-6, IL-8, TNF-a), and glial cell activation (glial fibrillary acidic protein). RESULTS. Native-LDL had no effect on cultured human M¨uller cells, but HOG-LDL exhibited marked toxicity, significantly decreasing viability and inducing autophagy, apoptosis, oxidative stress, expression of angiogenic factors, inflammation, and glial cell activation. Berberine attenuated all the effects of HOG-LDL (all P < 0.05), and its effects were mitigated by AMPK inhibition (P < 0.05). CONCLUSIONS. Berberine inhibits modified LDL-induced M¨uller cell injury by activating the AMPK pathway, and merits further study as an agent for preventing and/or treating DR.
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Abstract text Introduction: Cysticercosis results from the ingestion Taenia solium eggs directly by faecal-oral route or contaminated food or water. While, still considered a leading cause of acquired epilepsy in developed countries, this zoonosis has been controlled or eradicated in industrialized countries due to significant improvements in sanitation, pig rearing and slaughterhouse control systems. Objectives: the health burden of human cysticercosis in Portugal. Material and Metodes: We developed a retrospective study on human neurocysticercosis (NCC) hospitalisations based on the national database resulting from National Health Service (NHS) hospital episodes except those of Madeira and Azores Islands. Results: Between 2006 and 2013 there were 357 hospitalized NCC cases in Portugal. Annual frequency of cases between 2006-2013 kept stable (mean 45). NCC was most frequent in those aged 25-34 years (59; 16,5%) and those >75 years (65; 18,2%). Overall, mean age was 47,3 years (median age 45, standard deviation 41,1, mode 28) and 176 cases were in males (49,3%); no significant differences were observed between age and gender (t-student, p>0,05). In Norte Region cases tended to be older than in Lisboa and Vale do Tejo Region. Conclusions: The Directorate-General of Health established the National Observatory of Cysticercosis and Teniiasis which will define criteria for NCC cases monitoring and surveillance (hospitalized and non-hospitalized cases).
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Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species’ threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project – and avert – future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups – including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems – www.predicts.org.uk). We make site-level summary data available alongside this article. The full database will be publicly available in 2015.
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Ashton and colleagues concede in their response (Ashton, Lee, & Visser, in this issue), that neuroimaging methods provide a relatively unambiguous measure of the levels to which cognitive tasks co-recruit dif- ferent functional brain networks (task mixing). It is also evident from their response that they now accept that task mixing differs from the blended models of the classic literature. However, they still have not grasped how the neuroimaging data can help to constrain models of the neural basis of higher order ‘g’. Specifically, they claim that our analyses are invalid as we assume that functional networks have uncorrelated capacities. They use the simple analogy of a set of exercises that recruit multiple muscle groups to varying extents and highlight the fact that individual differences in strength may correlate across muscle groups. Contrary to their claim, we did not assume in the original article (Hampshire, High- field, Parkin, & Owen, 2012) that functional networks had uncorrelated capacities; instead, the analyses were specifically designed to estimate the scale of those correlations, which we referred to as spatially ‘diffuse’ factors
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Human exposure to persistent organic pollutants (POPs) is a certainty, even to long banned pesticides like o,p′-dichlorodiphenyltrichloroethane (o,p′-DDT), and its metabolites p,p′-dichlorodiphenyldichloroethylene (p,p′-DDE), and p,p′-dichlorodiphenyldichloroethane (p,p′-DDD). POPs are known to be particularly toxic and have been associated with endocrine-disrupting effects in several mammals, including humans even at very low doses. As environmental estrogens, they could play a critical role in carcinogenesis, such as in breast cancer. With the purpose of evaluating their effect on breast cancer biology, o,p′-DDT, p,p′-DDE, and p,p′-DDD (50–1000 nM) were tested on two human breast adenocarcinoma cell lines: MCF-7 expressing estrogen receptor (ER) α and MDA-MB-231 negative for ERα, regarding cell proliferation and viability in addition to their invasive potential. Cell proliferation and viability were not equally affected by these compounds. In MCF-7 cells, the compounds were able to decrease cell proliferation and viability. On the other hand, no evident response was observed in treated MDA-MB-231 cells. Concerning the invasive potential, the less invasive cell line, MCF-7, had its invasion potential significantly induced, while the more invasive cell line MDA-MB-231, had its invasion potential dramatically reduced in the presence of the tested compounds. Altogether, the results showed that these compounds were able to modulate several cancer-related processes, namely in breast cancer cell lines, and underline the relevance of POP exposure to the risk of cancer development and progression, unraveling distinct pathways of action of these compounds on tumor cell biology.
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As estratégias de malevolência implicam que um indivíduo pague um custo para infligir um custo superior a um oponente. Como um dos comportamentos fundamentais da sociobiologia, a malevolência tem recebido menos atenção que os seus pares o egoísmo e a cooperação. Contudo, foi estabelecido que a malevolência é uma estratégia viável em populações pequenas quando usada contra indivíduos negativamente geneticamente relacionados pois este comportamento pode i) ser eliminado naturalmente, ou ii) manter-se em equilíbrio com estratégias cooperativas devido à disponibilidade da parte de indivíduos malevolentes de pagar um custo para punir. Esta tese propõe compreender se a propensão para a malevolência nos humanos é inerente ou se esta se desenvolve com a idade. Para esse efeito, considerei duas experiências de teoria de jogos em crianças em ambiente escolar com idades entre os 6 e os 22 anos. A primeira, um jogo 2x2 foi testada com duas variantes: 1) um prémio foi atribuído a ambos os jogadores, proporcionalmente aos pontos acumulados; 2), um prémio foi atribuído ao jogador com mais pontos. O jogo foi desenhado com o intuito de causar o seguinte dilema a cada jogador: i) maximizar o seu ganho e arriscar ter menos pontos que o adversário; ou ii) decidir não maximizar o seu ganho, garantindo que este não era inferior ao do seu adversário. A segunda experiência consistia num jogo do ditador com duas opções: uma escolha egoísta/altruísta (A), onde o ditador recebia mais ganho, mas o seu recipiente recebia mais que ele e uma escolha malevolente (B) que oferecia menos ganhos ao ditador que a A mas mais ganhos que o recipiente. O dilema era que se as crianças se comportassem de maneira egoísta, obtinham mais ganho para si, ao mesmo tempo que aumentavam o ganho do seu colega. Se fossem malevolentes, então prefeririam ter mais ganho que o seu colega ao mesmo tempo que tinham menos para eles próprios. As experiências foram efetuadas em escolas de duas áreas distintas de Portugal (continente e Açores) para perceber se as preferências malevolentes aumentavam ou diminuíam com a idade. Os resultados na primeira experiência sugerem que (1) os alunos compreenderam a primeira variante como um jogo de coordenação e comportaram-se como maximizadores, copiando as jogadas anteriores dos seus adversários; (2) que os alunos repetentes se comportaram preferencialmente como malevolentes, mais frequentemente que como maximizadores, com especial ênfase para os alunos de 14 anos; (3) maioria dos alunos comportou-se reciprocamente desde os 12 até aos 16 anos de idade, após os quais começaram a desenvolver uma maior tolerância às escolhas dos seus parceiros. Os resultados da segunda experiência sugerem que (1) as estratégias egoístas eram prevalentes até aos 6 anos de idade, (2) as tendências altruístas emergiram até aos 8 anos de idade e (3) as estratégias de malevolência começaram a emergir a partir dos 8 anos de idade. Estes resultados complementam a literatura relativamente escassa sobre malevolência e sugerem que este comportamento está intimamente ligado a preferências de consideração sobre os outros, o paroquialismo e os estágios de desenvolvimento das crianças.************************************************************Spite is defined as an act that causes loss of payoff to an opponent at a cost to the actor. As one of the four fundamental behaviours in sociobiology, it has received far less attention than its counterparts selfishness and cooperation. It has however been established as a viable strategy in small populations when used against negatively related individuals. Because of this, spite can either i) disappear or ii) remain at equilibrium with cooperative strategies due to the willingness of spiteful individuals to pay a cost in order to punish. This thesis sets out to understand whether propensity for spiteful behaviour is inherent or if it develops with age. For that effect, two game-theoretical experiments were performed with schoolboys and schoolgirls aged 6 to 22. The first, a 2 x 2 game, was tested in two variants: 1) a prize was awarded to both players, proportional to accumulated points; 2), a prize was given to the player with most points. Each player faced the following dilemma: i) to maximise pay-off risking a lower pay-off than the opponent; or ii) not to maximise pay-off in order to cut down the opponent below their own. The second game was a dictator experiment with two choices, (A) a selfish/altruistic choice affording more payoff to the donor than B, but more to the recipient than to the donor, and (B) a spiteful choice that afforded less payoff to the donor than A, but even lower payoff to the recipient. The dilemma here was that if subjects behaved selfishly, they obtained more payoff for themselves, while at the same time increasing their opponent payoff. If they were spiteful, they would rather have more payoff than their colleague, at the cost of less for themselves. Experiments were run in schools in two different areas in Portugal (mainland and Azores) to understand whether spiteful preferences varied with age. Results in the first experiment suggested that (1) students understood the first variant as a coordination game and engaged in maximising behaviour by copying their opponent’s plays; (2) repeating students preferentially engaged in spiteful behaviour more often than maximising behaviour, with special emphasis on 14 year-olds; (3) most students engaged in reciprocal behaviour from ages 12 to 16, as they began developing higher tolerance for their opponent choices. Results for the second experiment suggested that (1) selfish strategies were prevalent until the age of 6, (2) altruistic tendencies emerged since then, and (3) spiteful strategies began being chosen more often by 8 year-olds. These results add to the relatively scarce body of literature on spite and suggest that this type of behaviour is closely tied with other-regarding preferences, parochialism and the children’s stages of development.
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This research examines the relationships between Human Resources Practices (HRP) and affective commitment, exhaustion, and cynicism of temporary workers. Furthermore, voluntariness and tenure with the client organization are assumed in the analysis as moderators. A sample of Temporary Agency workers was surveyed. It was assumed that HRP positively relates with affective commitment, while negatively with exhaustion and cynicism. Results confirmed the proposed relationships. Regarding the moderators, it has been proved that voluntariness partially weakens the relationships between HRP and temporary workers’ outcomes. However, contrary to the hypothesis, this effect cannot be affirmed also for the tenure with the client organization. Previous literature as well as implications of the findings are discussed.
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From 1993 to 2008, criminal investigations were conducted in the western part of Switzerland with special attention to blowfly and flesh fly species in order to estimate the post-mortem interval when requested by the police authorities. Flesh flies were found in only 33 cases out of 160. Five species of the genus Sarcophaga were identified (S. africa, S. argyrostoma, S. caerulescens, S. similis and S. sp.). The main species found on corpses (larval stage) was S. argyrostoma. The thermal constant (K) calculated for this species in Switzerland is 380.6 ± 16.3 (mean ± S.D.) degree-days. With the exception of S. caerulescens, found three times in the larval stage on corpses, the three other species are of minor forensic importance. S. argyrostoma is found during summer and indoors. This species colonises dead bodies, usually the same day as blowfly species, and it could be used to estimate the post-mortem interval. Other species are discussed in the light of current knowledge on their biology and ecology. It is recommended that voucher material be deposited in a museum, allowing further studies by relevant specialists, thereby helping investigators and avoiding misidentifications.
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Fifty-three patients with histologically proven carcinoma were injected with highly purified [131I]-labeled goat antibodies or fragments of antibodies against carcinoembryonic antigen (CEA). Each patient was tested by external photoscanning 4, 24, 36 and 48 h after injection. In 22 patients (16 of 38 injected with intact antibodies, 5 of 13 with F(ab')2 fragments and 1 of 2 with Fab' fragments), an increased concentration of 131I radioactivity corresponding to the previously known tumor location was detected by photoscanning 36-48 h after injection. Blood pool and secreted radioactivity was determined in all patients by injecting 15 min before scanning, [99mTc]-labeled normal serum albumin and free 99mTc04-. The computerized subtraction of 99mTc from 131I radioactivity enhanced the definition of tumor localization in the 22 positive patients. However, in spite of the computerized subtraction, interpretation of the scans remained doubtful for 12 patients and was entirely negative for 19 additional patients. In order to provide a more objective evaluation for the specificity of the tumor localization of antibodies, 14 patients scheduled for tumor resection were injected simultaneously with [131I]-labeled antibodies or fragments and with [125I]-labeled normal goat IgG or fragments. After surgery, the radioactivity of the two isotopes present either in tumor or adjacent normal tissues was measured in a dual channel scintillation counter. The results showed that the antibodies or their fragments were 2-4 times more concentrated in the tumor than in the normal tissues. In addition, it was shown that the injected antibodies formed immune complexes with circulating CEA and that the amount of immune complexes detectable in serum was roughly proportional to the level of circulating CEA.
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The metabolic and respiratory effects of intravenous 0.5 M sodium acetate (at a rate of 2.5 mmol/min during 120 min) were studied in nine normal human subjects. O2 consumption (VO2) and CO2 production (VCO2) were measured continuously by open-circuit indirect calorimetry. VO2 increased from 251 +/- 9 to 281 +/- 9 ml/min (P < 0.001), energy expenditure increased from 4.95 +/- 0.17 kJ/min baseline to 5.58 +/- 0.16 kJ/min (P < 0.001), and VCO2 decreased nonsignificantly (211 +/- 7 ml/min vs. 202 +/- 7 ml/min, NS). The extrapulmonary CO2 loss (i.e., bicarbonate generation and excretion) was estimated at 48 +/- 5 ml/min. This observation is consistent with 1 mol of bicarbonate generated from 1 mol of acetate metabolized. Alveolar ventilation decreased from 3.5 +/- 0.2 l/min basal to 3.1 +/- 0.2 l/min (P < 0.001). The minute ventilation (VE) to VO2 ratio decreased from 22.9 +/- 1.3 to 17.6 +/- 0.9 l/l (P < 0.005), arterial PO2 decreased from 93.2 +/- 1.9 to 78.7 +/- 1.6 mmHg (P < 0.0001), arterial PCO2 increased from 39.2 +/- 0.7 to 42.1 +/- 1.1 mmHg (P < 0.0001), pH from 7.40 +/- 0.005 to 7.50 +/- 0.007 (P < 0.005), and arterial bicarbonate concentration from 24.2 +/- 0.7 to 32.9 +/- 1.1 (P < 0.0001). These observations indicate that sodium acetate infusion results in substantial extrapulmonary CO2 loss, which leads to a relative decrease of total and alveolar ventilation.