973 resultados para Gray level gap length
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Previous findings point to the involvement of the dorsal raphe nucleus (DRN) and dorsal periaqueductal gray (dPAG) serotonergic receptors in the mediation of defensive responses that are associated with specific subtypes of anxiety disorders. These studies have mostly been conducted with rats tested in the elevated T-maze, an experimental model of anxiety that was developed to allow the measurement, in the same animal, of two behaviors mentioned: inhibitory avoidance and one-way escape. Such behavioral responses have been respectively related to generalized anxiety disorder (GAD) and panic disorder (PD). In order to assess the generality of these findings, in the current study we investigated the effects of the injection of 5-HT-related drugs into the DRN and dPAG of another rodent species, mouse, on the mouse defense test battery (MDTB), a test of a range of defensive behaviors to an unconditioned threat, a predator. Male CD-1 mice were tested in the MDTB after intra-DRN administration of the 5-HT(1A) receptor antagonist WAY-100635 or after intra-dPAG injection of two serotonergic agonists, the 5-HT1A receptor agonist 8-OH-DPAT and the 5-HT(2A/2C) receptor agonist DOI. Intra-DRN injection of WAY-100635 did not change behavioral responses of mice confronted with a rat in the MDTB. In the dPAG, both 8-OH-DPAT and DOI consistently impaired mouse escape behavior assessed in the MDTB. Intra-dPAG infusion of 8-OH-DPAT also decreased measures of mouse risk assessment in the rat exposure test. In conclusion, the current findings are in partial agreement with previous results obtained with rats tested in the elevated T-maze. Although there is a high level of similarity between the behavioral effects obtained in rats (elevated T-maze) and mice (MDTB and RET) with the infusion of 5-HT agonists into the dPAG, the same is not true regarding the effects of blockade of DRN 5-HT(1A) receptors in these rodent species. These data suggest that there may be differences between mice and rats regarding the involvement of the DRN in the mediation of defensive behaviors. (C) 2010 Elsevier B.V. and ECNP. All rights reserved.
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Electrical or chemical stimulation of the dorsal periaqueductal gray matter (DPAG) evokes escape, a defensive behavior that has been related to panic attacks. Injection of 5-HT(1A) or 5-HT(2A) receptor agonists into this midbrain area inhibits this response. It has been proposed that the impairment of 5-HT mechanisms controlling escape at the level of the DPAG may underlie the susceptibility to panic attacks that characterizes the panic disorder. In this study we evaluated the effects of the pharmacological manipulation of the dorsal raphe nucleus (DRN), which are the main source of 5-HT input to the DPAG, on the escape response evoked in rats by the intra-DPAG injection of the nitric oxide donor SIN-1. The results showed that DRN administration of the 5-HT(1A) receptor agonist 8-OH-DPAT which inhibits the activity of 5-HT neurons favored the expression of escape induced by SIN-1. Intra-DRN injection of the excitatory amino acid kainic acid or the 5-HT(1A) receptor antagonist WAY-100635 did not change escape expression. However, both compounds fully blocked the escape reaction generated by intra-DPAG injection of the excitatory amino acid D,L-homocysteic acid (DLH). Overall, the results indicate that 5-HT neurons in the DRN exert a bidirectional control upon escape behavior generated by the DPAG. Taking into account the effect of WAY-100635 on DLH-induced escape, they also strengthen the view that DRN 5-HT(1A) autoreceptors are under tonic inhibitory influence by 5-HT. (C) 2010 Elsevier B.V. All rights reserved.
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Assesses the status of women in Bangladesh by analysing the dynamics of female participation in labour force and education as well as gender earnings differentials at the macro level. The study finds evidence of growing commercialisation of women’s work in Bangladesh. Although the bulk of the female labour force is engaged in self-employment activities in the rural area or in low-skilled textile and readymade garment industries in the urban area, women’s participation in high-skill and entrepreneurial jobs as well as various decision-making bodies is also on the rise. While the gender wage differentials have been considerably reduced in many industries, in general women tend to be paid less than men. There have been remarkable improvements in women’s educational attainments compared to men. Further, female access to education is found to be highly correlated with overall female labour force participation, and relative to male participation. The overall results are suggestive of an improvement in the status of women in Bangladesh.
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Impulsivity based on Gray's [Gray, J. A. (1982) The neuropsychology of anxiety: an enquiry into the function of the septo-hippocampal system. New York: Oxford University Press: (1991). The neurophysiology of temperament. In J. Strelau & A. Angleitner. Explorations in temperament: international perspectives on theory and measurement. London. Plenum Press]. physiological model of personality was hypothesised to be more predictive of goal oriented criteria within the workplace than scales derived From Eysenck's [Eysenck. H.J. (1967). The biological basis of personality. Springfield, IL: Charles C. Thompson.] physiological model of personality. Results confirmed the hypothesis and also showed that Gray's scale of Impulsivity was generally a better predictor than attributional style and interest in money. Results were interpreted as providing support for Gray's Behavioural Activation System which moderates response to reward. (C) 2001 Elsevier Science Ltd. All rights reserved.
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While aggregate level pay equity comparisons between Australia and the UK confirm expectations based on their different wage distributions and regulatory systems, observation of trends and occupational level analysis reveal additional complexity. Our analysis suggests the need for a multi-faceted approach to closing the average gender pay gap.
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A numerical modelling strategy has been developed in order to quantify the magnitude of induced stresses at the boundaries of production level and undercut level drifts for various in situ stress environments and undercut scenarios. The results of the stress modelling were in line with qualitative experiential guidelines and a limited number of induced stress measurements documented from caving sites. A number of stress charts were developed which quantify the maximum boundary stresses in drift roofs for varying in situ stress regimes, depths and undercut scenarios. This enabled many of the experiential guidelines to be quantified and bounded. A limited number of case histories of support and support performance in cave mine drifts were compared to support recommendations using the NGI classification system, The stress charts were used to estimate the Stress Reduction Factor for this system. The back-analyses suggested that the NGI classification system might be able to give preliminary estimates of support requirements in caving mines with modifications relating to rock bolt length and the support of production level intersections. (C) 2002 Elsevier Science Ltd. All rights reserved.
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A genetic linkage map of mungbean (Vigna radiata, 2n = 2x = 22) consisting of 255 RFLP loci was developed using a recombinant inbred population of 80 individuals. The population was derived from an intersubspecific cross between the cultivated mungbean variety 'Berken' and a wild mungbean genotype 'ACC 41' (V radiata subsp. sublobata). The total length of the map, which comprised 13 linkage groups, spanned 737.9 cM with an average distance between markers of 3.0 cM and a maximum distance between linked markers of 15.4 cM. The mungbean map was compared to a previously published map of lablab (Lablab purpureus, 2n = 2x = 24) using a common set of 65 RFLP probes. In contrast to some other comparative mapping studies among members of the Fabaceae, where a high level of chromosomal rearrangement has been observed, marker order between mungbean and lablab was found to be highly conserved. However, the two genomes have apparently accumulated a large number of duplications/deletions after they diverged.
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Background: Physiotherapy has a very important role in the maintenance of the integumentary system integrity. There is very few evidence in humans. Nevertheless, there are some studies about tissue regeneration using low-level laser therapy (LLLT). Aim: To analyze the effectiveness of LLLT on scar tissue. Methods: Seventeen volunteers were stratified by age of their scars, and then randomly assigned to an experimental group (EG) — n = 9 – and a placebo group (PG) – n = 8. Fifteen sessions were conducted to both the groups thrice a week. However, in the PG, the laser device was switched off. Scars’ thickness, length, width, macroscopic aspect, pain threshold, pain perception, and itching were measured. Results: After 5 weeks, there were no statistically significant differences in any variable between both the groups. However, analyzing independently each group, EG showed a significant improvement in macroscopic aspect (p = 0.003) using LLLT. Taking into account the scars’ age, LLLT showed a tendency to decrease older scars’ thickness in EG. Conclusion: The intervention with LLLT appears to have a positive effect on the macroscopic scars’ appearance, and on old scars’ thickness, in the studied sample. However, it cannot be said for sure that LLLT has influence on scar tissue.
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This paper analyzes Knowledge Management (KM) as a political activity, made by the great political leaders of the world. We try to inspect if at the macro political level KM is made, and how. The research is interesting because given that we live in a Knowledge society, in the Information Era, it is more or less obvious that the political leaders should also do KM. However we don’t know of any previous study on KM and world leaders and this paper wants to be a first step to fill that gap. As a methodology we use literature review: given this one is a first preliminary study we use data we found in the Internet and other databases like EBSCO. We divide the analysis in two main parts: theoretical ideas first, and an application second. The second part is it self divided in two segments: the past and the present times. We find that rather not surprisingly, KM always was and is pervasive in the activity of the world leaders, and has become more and more diverse has power itself became to be more and more disseminated in the world. The study has the limitation of relying on insights and texts and not on interviews. But we believe it is very interesting to make this kind of analysis and such studies may help improving the democracies in the world.
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Tese apresentada como requisito parcial para obtenção do grau de Doutor em Estatística e Gestão de Informação pelo Instituto Superior de Estatística e Gestão de Informação da Universidade Nova de Lisboa
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RESUMO: Arl13b é uma importante proteína ciliar, presente em cílios primários e cílios móveis. Ratinhos mutantes para Arl13b têm comprimento dos cílios reduzido e defeitos nos B-túbulos dos cílios. Como consequência destes fenótipos, deficiências na Arl13b originam, em modelos animais, várias doenças congénitas, incluindo problemas no estabelecimento do eixo esquerda-direita, malformações cerebrais e deformações corporais. Nos seres humanos, deficiências na Arl13b levam a uma doença crónica congénita chamada Síndrome de Joubert. Por outro lado, a sobreexpressão de Arl13b origina cílios mais longos, no entanto existe uma ausência da caracterização dos fenótipos celulares e durante o desenvolvimento embrionário. Neste trabalho, quisemos explorar o efeito da sobre-expressão de Arl13b em embriões de peixezebra. Descobrimos que, ao nível ciliar, a sobre-expressão de Arl13b nas células aumenta o comprimento ciliar em cílios primários e móveis, no entanto, a esses cílios falta adequada acetilação da alfa-tubulina no citoesqueleto feito por microtúbulos. Os nossos resultados mostraram que esse efeito é específico de Arl13b sobre-expressão e quando se manipularam as enzimas responsáveis pela acetilação (Mec17) e pela de-acetilação (HDAC6) encontrámos uma sinergia potencial com ambas. Testámos ainda, que o aumento no comprimento ciliar não estava causalmente relacionado com a falta de acetilação, ou seja, os cílios com menos acetilação não eram necessariamente os mais longos. Também mostrámos que a sobre-expressão de Arl13b é capaz de restaurar o comprimento dos cílios em mutantes com cílios curtos e como isso pode ser explorado para um futuro potencial papel terapêutico para Arl13b. Em seguida, foi avaliado o impacto do aumento da quantidade de Arl13b no desenvolvimento embrionário do peixe-zebra. Observou-se que a sobre-expressão de Arl13b apresentava fenótipos muito fracos, quando comparados com a perda de função dos mutantes de Arl13b. Focados no inesperado fenótipo leve no estabelecimento do eixo esquerda-direita abordámos a questão através do estabelecimento de uma colaboração com matemáticos, descobrimos que os cílios mais longos que potencialmente têm a capacidade de movimentar mais fluido são atenuados por amplitudes de batimento menores, e, como resultado, estes longos cílios não prejudicam o movimento do fluido e consequentemente não afetam o estabelecimento dos padrões de esquerda-direita. Sugerimos assim que a Arl13b é um regulador chave, do comprimento ciliar. Descobrimos uma nova interação com as enzimas de acetilação/de-acetilação e levantamos novas hipóteses quanto aos mecanismos moleculares da função da Arl13b. Propomos um novo modelo para o mecanismo molecular da Arl13b na regulação do comprimento dos cílios onde podemos integrar os nossos resultados com os relatados na literatura. Este trabalho adiciona mais conhecimento para o mecanismo de ação da Arl13b e, portanto, fornece uma importante contribuição para o campo da investigação em cílios.---------------------------------------------------------------------------------------------------------------------- ABSTRACT: Arl13b is an important ciliary protein, present in primary and motile cilia. arl13b-/- mouse mutants have reduced cilia length and cilia B-tubule defects. As a consequence of these phenotypes, Arl13b loss of function animal models suffer from several congenital disorders including left-right problems, brain malformations and body deformations. In humans Arl13b depletion leads to a congenital chronic disease called Joubert Syndrome. On the other hand, overexpressing Arl13b leads to longer cilia but the characterization of the cellular and developmental phenotypes was missing. In this work we explore the effect of Arl13b overexpression in zebrafish embryos. We found that, at the ciliary level, Arl13b overexpression from 1 cell stage produces longer primary and motile cilia, but these cilia lack proper alpha tubulin acetylation of their microtubule cytoskeleton. Our results showed that this effect is specific from Arl13b overexpression and when we manipulated the enzymes responsible for acetylation, Mec17, and de-acetylation, HDAC6, we found a potential synergy of both mec17 knockdown and HDAC6 activity with Arl13b overexpression. We tested that the ciliary increase in length was not causally related to the lack of acetylation, meaning the more de-acetylated cilia were not necessarily the longer ones. We also showed that Arl13b overexpression is able to restore cilia length in short cilia mutants and how that may be explored to a potential future therapeutic role for Arl13b. Next, we evaluated the impact of increasing the amount of Arl13b in zebrafish embryonic development. We observed that Arl13b overexpression presented very mild phenotypes when compared to the loss of function mutants. We focused on the unexpected left-right mild phenotype and by establishing a mathematical modeling collaboration, we found out that the longer cilia generated force was attenuated by smaller beating amplitudes, and as a result, these long cilia were not impairing the cilia generated flow and the establishment of left-right patterning. We suggest that Arl13b is one key cilia length regulator. We disclosed a novel interaction with the acetylation / de-acetylation enzymes and raised new hypothesis as to the mechanisms of Arl13b function. We propose a new model for the Arl13b molecular mechanism of cilia length regulation where we integrate our findings with those reported in the literature. This work adds more knowledge to the Arl13b mechanism of action and therefore provides an important contribution to the cilia research field.
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Invasive cervical cancer (ICC) is the third most frequent cancer among women worldwide and is associated with persistent infection by carcinogenic human papillomaviruses (HPVs). The combination of large populations of viral progeny and decades of sustained infection may allow for the generation of intra-patient diversity, in spite of the assumedly low mutation rates of PVs. While the natural history of chronic HPVs infections has been comprehensively described, within-host viral diversity remains largely unexplored. In this study we have applied next generation sequencing to the analysis of intra-host genetic diversity in ten ICC and one condyloma cases associated to single HPV16 infection. We retrieved from all cases near full-length genomic sequences. All samples analyzed contained polymorphic sites, ranging from 3 to 125 polymorphic positions per genome, and the median probability of a viral genome picked at random to be identical to the consensus sequence in the lesion was only 40%. We have also identified two independent putative duplication events in two samples, spanning the L2 and the L1 gene, respectively. Finally, we have identified with good support a chimera of human and viral DNA. We propose that viral diversity generated during HPVs chronic infection may be fueled by innate and adaptive immune pressures. Further research will be needed to understand the dynamics of viral DNA variability, differentially in benign and malignant lesions, as well as in tissues with differential intensity of immune surveillance. Finally, the impact of intralesion viral diversity on the long-term oncogenic potential may deserve closer attention.
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Abstract Background: Acute coronary syndrome (ACS) is one of the main causes of morbidity and mortality in the modern world. A sedentary lifestyle, present in 85% of the Brazilian population, is considered a risk factor for the development of coronary artery disease. However, the correlation of a sedentary lifestyle with cardiovascular events (CVE) during hospitalization for ACS is not well established. Objective: To evaluate the association between physical activity level, assessed with the International Physical Activity Questionnaire (IPAQ), with in-hospital prognosis in patients with ACS. Methods: Observational, cross-sectional, and analytical study with 215 subjects with a diagnosis of ACS consecutively admitted to a referral hospital for cardiac patients between July 2009 and February 2011. All volunteers answered the short version of the IPAQ and were observed for the occurrence of CVE during hospitalization with a standardized assessment conducted by the researcher and corroborated by data from medical records. Results: The patients were admitted with diagnoses of unstable angina (34.4%), acute myocardial infarction (AMI) without ST elevation (41.4%), and AMI with ST elevation (24.2%). According to the level of physical activity, the patients were classified as non-active (56.3%) and active (43.7%). A CVE occurred in 35.3% of the cohort. The occurrence of in-hospital complications was associated with the length of hospital stay (odds ratio [OR] = 1.15) and physical inactivity (OR = 2.54), and was independent of age, systolic blood pressure, and prior congestive heart failure. Conclusion: A physically active lifestyle reduces the risk of CVE during hospitalization in patients with ACS.
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The morphological characteristics of the mandible of adult Chaetophractus vellerosus (Gray, 1865) and Zaedyus pichiy (Desmarest, 1804) were studied to establish its generalized design and to identify inter- and intra- (sexual) specific differences. Morphological descriptions were complemented with the application of univariate and multivariate (analysis of correlation matrices, PCA, discriminant analysis) techniques. The mandible of both species is very similar, and is characterized by elevated condyle, well developed angular process, distinct coronoid process, tooth row which extends to the rear end of the angle between body and ramus, and unfused but firm symphysis. Although both armadillos are omnivorous, a more slender configuration of the jaw in Z. pichiy could be indicative of a better adaptation of its masticatory apparatus to insectivory. The PCA showed an almost total segregation of both species on PC1 (47.7% of the total variance), with C. vellerosus being associated to mandibles taller and with wider body and ramus. Zaedyus pichiy was characterized by heavy loadings of length parameters on PC2 (22.6% of the variance). A small degree of sexual dimorphism was found, with size-based differences in C. vellerosus (larger mandibles in females) and shape-based differences in Z. pichiy (taller mandibles in males, longer ones in females). Correlations between variables were higher in males of both species, indicating a more stable shape of the mandible than in females. The selected parameters to discriminate sexes were the body length of the mandible in C. vellerosus (correct classification: ca. 86% in males, 81% in females), and the height of the mandible at the level of the last tooth in Z. pichiy (near 85% of right assignment in both sexes). The inclusion of a new variable (body length) in the latter species improved the classification of the females to 100%. Teeth are typically 10 in C. vellerosus and 9 in Z. pichiy, but aberrancies in this basic number, such as unilateral or bilateral extra or fewer teeth, are common.
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In many high income developed countries, obesity is inversely associated with educational level. In some countries, a widening gap of obesity between educational groups has been reported. The aim of this study was to assess trends in body mass index (BMI) and in prevalence of overweight and obesity and their association with educational level in the adult Swiss population. Four cross-sectional National health interview surveys conducted in 1992/93 (n = 14,521), 1997 (n = 12,474), 2002 (n = 18,908) and 2007 (n = 17,879) using representative samples of the Swiss population (age range 18-102 years). BMI was derived from self-reported data. Overweight was defined as BMI > or = 25 and <30 kg/m(2), and obesity as BMI > or = 30 kg/m(2). Mean (+/- standard deviation) BMI increased from 24.7 +/- 3.6 in 1992/3 to 25.4 +/- 3.6 kg/m2 in 2007 in men and 22.8 +/- 3.8 to 23.7 +/- 4.3 kg/m(2) in women. Between 1992/3 and 2007, the prevalence of overweight + obesity increased from 40.4% to 49.5% in men and from 22.3% to 31.3% in women, while the prevalence of obesity increased from 6.3% to 9.4% in men and from 4.9% to 8.5% in women. The rate of increase in the prevalence of obesity was greater between 1992/3 and 2002 (men: +0.26%/year; women: +0.31%/year) than between 2002 and 2007 (men: +0.10%/year; women: +0.10%/year). A sizable fraction (approximately 25%) of the increasing mean BMI was due to increasing age of the participants over time. The increase was larger in low than high education strata of the population. BMI was strongly associated with low educational level among women and this gradient remained fairly constant over time. A weaker similar gradient by educational level was apparent in men, but it tended to increase over time. In Switzerland, overweight and obesity increased between 1992 and 2007 and was associated with low education status in both men and women. A trend towards a stabilization of mean BMI levels was noted in most age categories since 2002. The increase in the prevalence of obesity was larger in low education strata of the population. These findings suggest that obesity preventive measures should be targeted according to educational level in Switzerland.