969 resultados para Not in our genes
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Neuroinflammation is the local reaction of the brain to infection, trauma, toxic molecules or protein aggregates. The brain resident macrophages, microglia, are able to trigger an appropriate response involving secretion of cytokines and chemokines, resulting in the activation of astrocytes and recruitment of peripheral immune cells. IL-1β plays an important role in this response; yet its production and mode of action in the brain are not fully understood and its precise implication in neurodegenerative diseases needs further characterization. Our results indicate that the capacity to form a functional NLRP3 inflammasome and secretion of IL-1β is limited to the microglial compartment in the mouse brain. We were not able to observe IL-1β secretion from astrocytes, nor do they express all NLRP3 inflammasome components. Microglia were able to produce IL-1β in response to different classical inflammasome activators, such as ATP, Nigericin or Alum. Similarly, microglia secreted IL-18 and IL-1α, two other inflammasome-linked pro-inflammatory factors. Cell stimulation with α-synuclein, a neurodegenerative disease-related peptide, did not result in the release of active IL-1β by microglia, despite a weak pro-inflammatory effect. Amyloid-β peptides were able to activate the NLRP3 inflammasome in microglia and IL-1β secretion occurred in a P2X7 receptor-independent manner. Thus microglia-dependent inflammasome activation can play an important role in the brain and especially in neuroinflammatory conditions.
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Foods derived from animals are an important source of nutrients in the diet but there is considerable uncertainty about whether or not these foods contribute to increased risk of various chronic diseases. For milk in particular there appears to be an enormous mismatch between both the advice given on milk/dairy foods items by various authorities and public perceptions of harm from the consumption of milk and dairy products, and the evidence from long-term prospective cohort studies. Such studies provide convincing evidence that increased consumption of milk can lead to reductions in the risk of vascular disease and possibly some cancers and of an overall survival advantage from the consumption of milk, although the relative effect of milk products is unclear. Accordingly, simply reducing milk consumption in order to reduce saturated fatty acid (SFA) intake is not likely to produce benefits overall though the production of dairy products with reduced SFA contents is likely to be helpful. For red meat there is no evidence of increased risk of vascular diseases though processed meat appears to increase the risk substantially. There is still conflicting and inconsistent evidence on the relationship between consumption of red meat and the development of colorectal cancer, but this topic should not be ignored. Likewise, the role of poultry meat and its products as sources of dietary fat and fatty acids is not fully clear. There is concern about the likely increase in the prevalence of dementia but there are few data on the possible benefits or risks from milk and meat consumption. The future role of animal nutrition in creating foods closer to the optimum composition for long-term human health will be increasingly important. Overall, the case for increased milk consumption seems convincing, although the case for high-fat dairy products and red meat is not. Processed meat products do seem to have negative effects on long-term health and although more research is required, these effects do need to be put into the context of other risk factors to long-term health such as obesity, smoking and alcohol consumption.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Recent findings provide evidence of inflammasome critical role in the predisposition to autoimmune disorders. The involvement of inflammasome in the pathogenesis of systemic lupus erythematosus (SLE) has been hypothesized even if no significant association within inflammasome genes mutations or polymorphisms and lupus has been reported yet. We analyzed 14 single nucleotide polymorphisms (SNPs) within 7 inflammasome genes (NLRP1, NLRP3, NLRC4, AIM2, CARD8, CASP1, IL1B) in 144 patients affected by systemic lupus erythematosus and in 158 healthy controls from Southern Brazilian (state of Sao Paulo) with the aim of disclosing the possible role of inflammasome genes in the susceptibility of SLE. Our results demonstrated that NLRP1 rs2670660 SNP and the NLRP1 rs12150220-rs2670660 A-G haplotype were associated with SLE in our study population, and in particular with the development of nephritis, rash and arthritis. These findings are concordant with previously reported association of NLRP1 with vitiligo and type-1 diabetes underlining once more the involvement of NALP1 inflammasome in the pathogenesis of autoimmune disorders.
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Telomerase activity is readily detectable in extracts from human hematopoietic stem and progenitor cells, but appears unable to maintain telomere length with proliferation in vitro and with age in vivo. We performed a detailed study of the telomere length by flow FISH analysis in leukocytes from 835 healthy individuals and 60 individuals with reduced telomerase activity. Healthy individuals showed a broad range in average telomere length in granulocytes and lymphocytes at any given age. The average telomere length declined with age at a rate that differed between age-specific breakpoints and between cell types. Gender differences between leukocyte telomere lengths were observed for all cell subsets studied; interestingly, this trend could already be detected at birth. Heterozygous carriers for mutations in either the telomerase reverse transcriptase (hTERT) or the telomerase RNA template (hTERC) gene displayed striking and comparable telomere length deficits. Further, non-carrier relatives of such heterozygous individuals had somewhat shorter leukocyte telomere lengths than expected; this difference was most profound for granulocytes. Failure to maintain telomere homeostasis as a result of partial telomerase deficiency is thought to trigger cell senescence or cell death, eventually causing tissue failure syndromes. Our data are consistent with these statements and suggest that the likelihood of similar processes occurring in normal individuals increases with age. Our work highlights the essential role of telomerase in the hematopoietic system and supports the notion that telomerase levels in hematopoietic cells, while limiting and unable to prevent overall telomere shortening, are nevertheless crucial to maintain telomere homeostasis with age.
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In writing “Not in the Legends”, one of the images and concepts which constantly returned was that of pilgrimage. I began to write these poems while studying abroad in London, after having passed the previous semester in France and travelling around Europe. There was something in the repetition of sightseeing— walking six miles in Luxembourg to see the grave of General Patton, taking photographs of the apartment where Sylvia Plath ended her life, bowing before the bones of saints, searching through Père Lachaise for the grave of Théodore Gericault— which struck me as numinous and morbid. At the same time, I came to love living abroad and I grew discontent with both remaining and returning. I wanted the opportunity to live everywhere all the time and not have to choose between home and away. Returning from abroad, I turned my attention to the landscape of my native country. I found in the New England pilgrims a narrative of people who had left their home in search of growth and freedom. In these journeys I began to appreciate the significance of place and tried to understand what it meant to move from one place to another, how one chose a home, and why people searched for meaning in specific locations. The processes of moving from student to worker and from childhood to adulthood have weighed on me. I began to see these transitions towards maturity as travels to a different land. Memory and nostalgia are their own types of pilgrimage in their attempts to return to lost places, as is the reading of literature. These pilgrimages, real and metaphorical, form the thematic core of the collection. I read the work of many poets who came before me, returning to the places where the Canon was forged. Those poets have a large presence in the work I produced. I wondered how I, as a young poet, could earn my own place in the tradition and sought models in much the same way a painter studies the brushstrokes of a master. In the process, I have tried to uncover what it means to be a poet. Is it something like being a saint? Is it something like being a colonist? Or is to be the one who goes in search of saints and colonists? In trying to measure my own life and work based on the precedent, I have questioned what role era and generation have on the formation of identity. I focused my reading heavily on the early years of English poetry, trying to find the essence of the time when the language first achieved the transcendence of verse. In following the development of English poetry through Coleridge, John Berryman, and Allison Titus, I have explored the progression of those basic virtues in changing contexts. Those bearings, applied to my modern context, helped to shape the poetry I produced. Many of the poems in “Not in the Legends” are based on my own personal experience. In my recollections I have tried to interrogate nostalgia rather than falling into mere reminiscence. Rather than allowing myself poems of love and longing, I have tried to find the meaning of those emotions. A dominant conflict exists between adventure and comfort which mirrors the central engagement with the nature of being “here” or “there”. It is found in scenes of domesticity and wilderness as I attempt to understand my own simultaneous desire for both. For example, in “Canned Mangoes…” the intrusion of nature, even in a context as innocuous as a poem by Sir Walter Raleigh, unravels ordinary comforts of the domestic sphere. The character of “The Boy” from Samuel Beckett’s Waiting for Godot proved such an interesting subject for me because he is one who can transcend the normal boundaries of time and place. The title suggests connections to both place and time. “Legends” features the dual meaning of both myths and the keys to maps. To propose something “Not in the Legends” is to find something which has no precedent in our histories and our geographies, something beyond our field of knowledge and wholly new. One possible interpretation I devised was that each new generation lives a novel existence, the future being the true locus of that which is beyond our understanding. The title comes from Keats’ “Hyperion, a Fragment”, and details the aftermath of the Titanomachy. The Titans, having fallen to the Olympians, are a representation of the passing of one generation for the next. Their dejection is expressed by Saturn, who laments: Not in my own sad breast, Which is its own great judge and searcher out, Can I find reason why ye should be thus: Not in the legends of the first of days… (129-132) The emotions of the conquered Titans are unique and without antecedent. They are experiencing feelings which surpass all others in history. In this, they are the equivalent of the poet who feels that his or her own sufferings are special. In contrast are Whitman’s lines from “Song of Myself” which serve as an epigraph to this collection. He contends for a sense of continuity across time, a realization that youth, age, pleasure, and suffering have always existed and will always exist. Whitman finds consolation in this unity, accepting that kinship with past generations is more important that his own individuality. These opposing views offer two methods of presenting the self in history. The instinct of poetry suggests election. The poet writes because he feels his experiences are special, or because he believes he can serve as a synecdoche for everyone. I have fought this instinct by trying to contextualize myself in history. These poems serve as an attempt at prosopography with my own narrative a piece of the whole. Because the earth abides forever, our new stories get printed over the locations of the old and every place becomes a palimpsest of lives and acts. In this collection I have tried to untangle some of those layers, especially my own, to better understand the sprawling legend of history.
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Our previous gene expression analysis identified phospholipase A2 group IIA (PLA2G2A) as a potential biomarker of ovarian endometriosis. The aim of this study was to evaluate PLA2G2A mRNA and protein levels in tissue samples (endometriomas and normal endometrium) and in serum and peritoneal fluid of ovarian endometriosis patients and control women. One-hundred and sixteen women were included in this study: the case group included 70 ovarian endometriosis patients, and the control group included 38 healthy women and 8 patients with benign ovarian cysts. We observed 41.6-fold greater PLA2G2A mRNA levels in endometrioma tissue, compared to normal endometrium tissue. Using Western blotting, PLA2G2A was detected in all samples of endometriomas, but not in normal endometrium, and immunohistochemistry showed PLA2G2A-specific staining in epithelial cells of endometrioma paraffin sections. However, there were no significant differences in PLA2G2A levels between cases and controls according to ELISA of peritoneal fluid (6.0 ± 4.4 ng/ml, 6.6 ± 4.3 ng/ml; p = 0.5240) and serum (2.9 ± 2.1 ng/ml, 3.1 ± 2.2 ng/ml; p = 0.7989). Our data indicate that PLA2G2A is implicated in the pathophysiology of ovarian endometriosis, but that it cannot be used as a diagnostic biomarker.
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Acknowledgments Financial Support: HERU and HSRU receive a core grant from the Chief Scientist’s Office of the Scottish Government Health and Social Care Directorates, and the Centre for Clinical epidemiology & Evaluation is funded by Vancouver Coastal Health Authority. The model used for the illustrative case study in this paper was developed as part of a NHS Technology Assessment Review, funded by the National Institute for Health Research (NIHR) Health Technology Assessment Program (project number 09/146/01). The views and opinions expressed in this paper are those of the authors and do not necessarily reflect those of the Scottish Government, NHS, Vancouver Coastal Health, NIHR HTA Program or the Department of Health. The authors wish to thank Kathleen Boyd and members of the audience at the UK Health Economists Study Group, for comments received on an earlier version of this paper. We also wish to thank Cynthia Fraser (University of Aberdeen) for literature searches undertaken to inform the manuscript, and Mohsen Sadatsafavi (University of British Columbia) for comments on an earlier draft
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Five human diseases are due to an excessive number of CAG repeats in the coding regions of five different genes. We have analyzed the repeat regions in four of these genes from nonhuman primates, which are not known to suffer from the diseases. These primates have CAG repeats at the same sites as in human alleles, and there is similar polymorphism of repeat number, but this number is smaller than in the human genes. In some of the genes, the segment of poly(CAG) has expanded in nonhuman primates, but the process has advanced further in the human lineage than in other primate lineages, thereby predisposing to diseases of CAG reiteration. Adjacent to stretches of homogeneous present-day codon repeats, previously existing codons of the same kind have undergone nucleotide substitutions with high frequency. Where these lead to amino acid substitutions, the effect will be to reduce the length of the original homopolymeric stretch in the protein.
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Neuroblastoma (NB), a tumor arising from the sympathetic nervous system, is one of the most common malignancies in childhood. Several recent reports on the p53 genotype found virtually exclusive wild-type status in primary tumors, and it was postulated that p53 plays no role in the development of NB. Here, however, we report that the vast majority of undifferentiated NBs exhibit abnormal cytoplasmic sequestration of wild-type p53. This inability of p53 to translocate to the nucleus presumably prevents the protein from functioning as a suppressor. Thirty of 31 cases (96%) of undifferentiated NB showed elevated levels of wild-type p53 in the cytoplasm of all tumor cells concomittant with a lack of nuclear staining. p53 immunoprecipitation from tumor tissues showed a 4.5- to 8-fold increase over normal protein levels. All of 10 tumors analyzed harbored wild-type p53 by direct sequencing of full-length cDNA and Southern blot. In addition, no MDM-2 gene amplification was seen in all 11 tumors analyzed. In contrast, no p53 abnormality was detected in 14 differentiated ganglioneuroblastomas and 1 benign ganglioneuroma. We conclude that loss of p53 function seems to play a major role in the tumorigenesis of undifferentiated NB. This tumor might abrogate the transactivating function of p53 by inhibiting its access to the nucleus, rather than by gene mutation. Importantly, our results suggest that (i) this could be a general mechanism for p53 inactivation not limited to breast cancer (where we first described it) and that (ii) it is found in a tumor previously not thought to be affected by p53 alteration.
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There is still a matter of debate around the nature of personal neglect. Is it an attention disorder or a body representation disorder? Here we investigate the presence of body representation deficits (i.e., the visuo-spatial body map) in right and left brain-damaged patients and in particular in those affected by personal neglect. 23 unilateral brain-damaged patients (5 left-brain-damaged and 18 right-brain-damaged patients) and 15 healthy controls took part in the study. The visuo-spatial body map was assessed by means of the “Frontal body-evocation subtest (FBE),” in which participants have to put tiles representing body parts on a small wooden board where only the head is depicted as a reference point. In order to compare performance on the FBE with performance on an inanimate object that had well-defined right and left sides, participants also performed the “Car test.” Group statistical analysis shows that the performance of patients with personal neglect is significantly worse than that of the controls and patients without personal neglect in the FBE but not in the Car test. Single case analyses of the five patients with pure personal neglect confirm the results of group analysis. Our data supports the hypothesis that personal neglect is a pervasive body representation disorder.
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Key to predicting impacts of predation is understanding the mechanisms through which predators impact prey populations. While consumptive effects are well-known, non-consumptive predator effects (risk effects) are increasingly being recognized as important. Studies of risk effects, however, have focused largely on how trade-offs between food and safety affect fitness. Less documented, and appreciated, is the potential for predator presence to directly suppress prey reproduction and affect life-history characteristics. For the first time, we tested the effects of visual predator cues on reproduction of two prey species with different reproductive modes, lecithotrophy (i.e. embryonic development primarily fueled by yolk) and matrotrophy (i.e. energy for embryonic development directly supplied by the mother to the embryo through a vascular connection). Predation risk suppressed reproduction in the lecithotrophic prey (Gambusia holbrokii) but not the matrotroph (Heterandria formosa). Predator stress caused G. holbrooki to reduce clutch size by 43%, and to produce larger and heavier offspring compared to control females. H. formosa, however, did not show any such difference. In G. holbrooki we also found a significantly high percentage (14%) of stillbirths in predator-exposed treatments compared to controls (2%). To the best of our knowledge, this is the first direct empirical evidence of predation stress affecting stillbirths in prey. Our results suggest that matrotrophy, superfetation (clutch overlap), or both decrease the sensitivity of mothers to environmental fluctuation in resource (food) and stress (predation risk) levels compared to lecithotrophy. These mechanisms should be considered both when modeling consequences of perceived risk of predation on prey-predator population dynamics and when seeking to understand the evolution of reproductive modes.