148 research outputs found
Tratamento do câncer de laringe: revisão da literatura publicada nos últimos dez anos
Resumo:Este estudo tem como objetivo analisar as características da produção bibliográfica científica sobre o tratamento do câncer de laringe nos últimos dez anos. Foram seguidos os preceitos do Cochrane Handbook, que envolveu a formulação da questão a ser investigada, a localização, a seleção dos estudos e a avaliação crítica dos artigos. Os artigos publicados entre 2002 e 2011 foram selecionados por meio das bases de dados LILACS e ScIELO, utilizando-se o descritor laringect$ e na base de dados PubMed, utilizando-se o descritor laringect*. Analisaram-se os textos completos, potencialmente relevantes para a revisão, utilizando-se um formulário padronizado, quando os seguintes dados foram coletados: objetivos, desenho da pesquisa, resultados encontrados e discussão sobre o tratamento em câncer de laringe. Inicialmente foram identificados 299 estudos. Após a revisão dos títulos e resumos, consideração dos critérios de inclusão e exclusão, verificação da coerência com a temática pesquisada e eliminação dos estudos que estavam concomitantemente em mais de uma base de dados, 72 foram efetivamente analisados por referirem nos descritores e/ou nos resumos o tema câncer de laringe. A partir desta pesquisa, é possível verificar lacunas e oportunidades para o desenvolvimento de estudos que verifiquem técnicas padronizadas de tratamento do câncer de laringe com o aumento de estudos analíticos e de intervenção baseados em ensaios clínicos randomizados, especialmente considerando diretrizes como CONSORT, STROBE e GRADE para o seu planejamento e publicação
Determinants of the exclusive breastfeeding abandonment: psychosocial factors
OBJECTIVE To assess the determinants of exclusive breastfeeding abandonment. METHODS Longitudinal study based on a birth cohort in Viçosa, MG, Southeastern Brazil. In 2011/2012, 168 new mothers accessing the public health network were followed. Three interviews, at 30, 60, and 120 days postpartum, with the new mothers were conducted. Exclusive breastfeeding abandonment was analyzed in the first, second, and fourth months after childbirth. The Edinburgh Postnatal Depression Scale was applied to identify depressive symptoms in the first and second meetings, with a score of ≥ 12 considered as the cutoff point. Socioeconomic, demographic, and obstetric variables were investigated, along with emotional conditions and the new mothers’ social network during pregnancy and the postpartum period. RESULTS The prevalence of exclusive breastfeeding abandonment at 30, 60, and 120 days postpartum was 53.6% (n = 90), 47.6% (n = 80), and 69.6% (n = 117), respectively, and its incidence in the fourth month compared with the first was 48.7%. Depressive symptoms and traumatic delivery were associated with exclusive breastfeeding abandonment in the second month after childbirth. In the fourth month, the following variables were significant: lower maternal education levels, lack of homeownership, returning to work, not receiving guidance on breastfeeding in the postpartum period, mother’s negative reaction to the news of pregnancy, and not receiving assistance from their partners for infant care. CONCLUSIONS Psychosocial and sociodemographic factors were strong predictors of early exclusive breastfeeding abandonment. Therefore, it is necessary to identify and provide early treatment to nursing mothers with depressive symptoms, decreasing the associated morbidity and promoting greater duration of exclusive breastfeeding. Support from health professionals, as well as that received at home and at work, can assist in this process
Interplay of ribosomal DNA Loci in nucleolar dominance: dominant NORs are up-regulated by chromatin dynamics in the wheat-rye system
Background: Chromatin organizational and topological plasticity, and its functions in gene expression regulation, have
been strongly revealed by the analysis of nucleolar dominance in hybrids and polyploids where one parental set of
ribosomal RNA (rDNA) genes that are clustered in nucleolar organizing regions (NORs), is rendered silent by epigenetic
pathways and heterochromatization. However, information on the behaviour of dominant NORs is very sparse and needed
for an integrative knowledge of differential gene transcription levels and chromatin specific domain interactions.
Methodology/Principal Findings: Using molecular and cytological approaches in a wheat-rye addition line (wheat genome
plus the rye nucleolar chromosome pair 1R), we investigated transcriptional activity and chromatin topology of the wheat
dominant NORs in a nucleolar dominance situation. Herein we report dominant NORs up-regulation in the addition line
through quantitative real-time PCR and silver-staining technique. Accompanying this modification in wheat rDNA
trascription level, we also disclose that perinucleolar knobs of ribosomal chromatin are almost transcriptionally silent due to
the residual detection of BrUTP incorporation in these domains, contrary to the marked labelling of intranucleolar
condensed rDNA. Further, by comparative confocal analysis of nuclei probed to wheat and rye NORs, we found that in the
wheat-rye addition line there is a significant decrease in the number of wheat-origin perinucleolar rDNA knobs,
corresponding to a diminution of the rDNA heterochromatic fraction of the dominant (wheat) NORs.
Conclusions/Significance: We demonstrate that inter-specific interactions leading to wheat-origin NOR dominance results not
only on the silencing of rye origin NOR loci, but dominant NORs are alsomodified in their transcriptional activity and interphase
organization. The results show a cross-talk between wheat and rye NORs, mediated by ribosomal chromatin dynamics,
revealing a conceptual shift from differential amphiplasty to ‘mutual amphiplasty’ in the nucleolar dominance process.This work was supported by the Fundação para a Ciência e Tecnologia (projects POCI/BIA-BDE/57575/2004 to M.S. and POCI/BIA-BCM/59389/2004 to N.N.
The N-P-K soil nutrient balance of portuguese cropland in the 1950s: the transition from organic to chemical fertilization
Agricultural nutrient balances have been receiving increasing attention in both historical and
nutrient management research. The main objectives of this study were to further develop balance
methodologies and to carry out a comprehensive assessment of the functioning and nutrient cycling
of 1950s agroecosystems in Portugal. Additionally, the main implications for the history of agriculture
in Portugal were discussed from the standpoint of soil fertility. We used a mass balance approach
that comprises virtually all nitrogen (N), phosphorus (P) and potassium (K) inputs and outputs from
cropland topsoil for average conditions in the period 1951–56. We found a consistent deficit in N, both
for nationwide (−2.1 kg.ha−1.yr−1) and arable crops (−1.6 kg.ha−1.yr−1) estimates, that was rectified
in the turn to the 1960 decade. P and K were, in contrast, accumulating in the soil (4.2–4.6 kg.ha−1.yr−1
and 1.0–3.0 kg.ha−1.yr−1, respectively). We observed that the 1950s is the very moment of inflection
from an agriculture fertilized predominantly through reused N in biomass (livestock excretions plus
marine, plant and human waste sources) to one where chemical fertilizers prevailed. It is suggested that
N deficiency played an important role in this transitioninfo:eu-repo/semantics/publishedVersio
IL-1β Is Upregulated in the Diabetic Retina and Retinal Vessels: Cell-Specific Effect of High Glucose and IL-1β Autostimulation
Many molecular and cellular abnormalities detected in the diabetic retina support a role for IL-1β-driven neuroinflammation in the pathogenesis of diabetic retinopathy. IL-1β is well known for its role in the induction and, through autostimulation, amplification of neuroinflammation. Upregulation of IL-1β has been consistently detected in the diabetic retina; however, the mechanisms and cellular source of IL-1β overexpression are poorly understood. The aim of this study was to investigate the effect of high glucose and IL-1β itself on IL-1β expression in microglial, macroglial (astrocytes and Müller cells) and retinal vascular endothelial cells; and to study the effect of diabetes on the expression of IL-1β in isolated retinal vessels and on the temporal pattern of IL-1β upregulation and glial reactivity in the retina of streptozotocin-diabetic rats. IL-1β was quantified by RealTime RT-PCR and ELISA, glial fibrillar acidic protein, α2-macroglobulin, and ceruloplasmin by immunoblotting. We found that high glucose induced a 3-fold increase of IL-1β expression in retinal endothelial cells but not in macroglia and microglia. IL-1β induced its own synthesis in endothelial and macroglial cells but not in microglia. In retinal endothelial cells, the high glucose-induced IL-1β overexpression was prevented by calphostin C, a protein kinase C inhibitor. The retinal vessels of diabetic rats showed increased IL-1β expression as compared to non-diabetic rats. Retinal expression of IL-1β increased early after the induction of diabetes, continued to increase with progression of the disease, and was temporally associated with upregulation of markers of glial activation. These findings point to hyperglycemia as the trigger and to the endothelium as the origin of the initial retinal upregulation of IL-1β in diabetes; and to IL-1β itself, via autostimulation in endothelial and macroglial cells, as the mechanism of sustained IL-1β overexpression. Interrupting the vicious circle triggered by IL-1β autostimulation could limit the progression of diabetic retinopathy
Control of Metabolic Homeostasis by Stress Signaling Is Mediated by the Lipocalin NLaz
Metabolic homeostasis in metazoans is regulated by endocrine control of insulin/IGF signaling (IIS) activity. Stress and inflammatory signaling pathways—such as Jun-N-terminal Kinase (JNK) signaling—repress IIS, curtailing anabolic processes to promote stress tolerance and extend lifespan. While this interaction constitutes an adaptive response that allows managing energy resources under stress conditions, excessive JNK activity in adipose tissue of vertebrates has been found to cause insulin resistance, promoting type II diabetes. Thus, the interaction between JNK and IIS has to be tightly regulated to ensure proper metabolic adaptation to environmental challenges. Here, we identify a new regulatory mechanism by which JNK influences metabolism systemically. We show that JNK signaling is required for metabolic homeostasis in flies and that this function is mediated by the Drosophila Lipocalin family member Neural Lazarillo (NLaz), a homologue of vertebrate Apolipoprotein D (ApoD) and Retinol Binding Protein 4 (RBP4). Lipocalins are emerging as central regulators of peripheral insulin sensitivity and have been implicated in metabolic diseases. NLaz is transcriptionally regulated by JNK signaling and is required for JNK-mediated stress and starvation tolerance. Loss of NLaz function reduces stress resistance and lifespan, while its over-expression represses growth, promotes stress tolerance and extends lifespan—phenotypes that are consistent with reduced IIS activity. Accordingly, we find that NLaz represses IIS activity in larvae and adult flies. Our results show that JNK-NLaz signaling antagonizes IIS and is critical for metabolic adaptation of the organism to environmental challenges. The JNK pathway and Lipocalins are structurally and functionally conserved, suggesting that similar interactions represent an evolutionarily conserved system for the control of metabolic homeostasis
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