324 research outputs found
Hemigrammus arua, a new species of characid (Characiformes: Characidae) from the lower Amazon, Brazil
A new Hemigrammus species is described from tributaries of the igarapĂ© Juruti Grande and rio Arapiuns, lower rio Amazonas, ParĂĄ State, Brazil. The new species can be easily diagnosed from all its congeners, except from Hemigrammus stictus (Durbin), by possessing a single, large humeral spot which extends longitudinally from the fifth or sixth to the posterior margin of eighth to tenth, lateral line scales. It can be distinguished from Hemigrammus stictus by possessing a pronounced upper, anteriorly-oriented extension in the humeral blotch, conferring an inverted-comma shape to it, and by displaying a distinct life color pattern.Uma nova espĂ©cie de Hemigrammus Ă© descrita de afluentes do igarapĂ© Juruti Grande e do rio Arapiuns, baixo rio Amazonas, Estado do ParĂĄ, Brasil. A nova espĂ©cie pode ser facilmente diagnosticada de todos seus congĂȘneres, exceto Hemigrammus stictus (Durbin), por possuir uma Ășnica, grande mancha umeral que se estende da quinta ou sexta escamas Ă margem posterior da oitava Ă dĂ©cima escama da linha lateral. Ela pode ser distinguida de Hemigrammus stictus por possuir uma extensĂŁo da mancha umeral pronunciada e anteriormente orientada, o que lhe confere uma forma de vĂrgula invertida e por possuir um padrĂŁo de colorido distinto em vida.FAPES
Trajectories of Sensation Seeking Among Puerto Rican Children and Youth
Objective: To document the natural course of sensation seeking from childhood to adolescence, characterize distinct sensation seeking trajectories, and examine how these trajectories vary according to selected predictors. Method: Data were obtained from the Boricua Youth Study, a longitudinal study of 2,491 children and adolescents of Puerto Rican background (3 assessments from 2000 to 2004). First, age-specific sensation seeking levels were characterized, and then age-adjusted residuals were analyzed using growth mixture models. Results: On average, sensation seeking was stable in childhood (ages 5â10 years) and increased during adolescence (ages 11â17 years). Mean scores of sensation seeking were higher in the South Bronx versus Puerto Rico and among males versus females. Four classes of sensation seeking trajectories were observed: most study participants had age-expected sensation seeking trajectories following the average for their age (ânormative,â 43.8%); others (37.2%) remained consistently lower than the expected average for their age (âlowâ sensation seeking); some (12.0%) had an âacceleratedâ sensation seeking trajectory, increasing at a faster rate than expected; and a minority (7.0%) had a decreasing sensation seeking trajectory that started high but decreased, reaching scores slightly higher than the age-average sensation seeking scores (âstabilizersâ). Site (South Bronx versus Puerto Rico) and gender were predictors of membership in a specific class of sensation seeking trajectory. Conclusion: It is important to take a developmental approach when examining sensation seeking and to consider gender and the social environment when trying to understand how sensation seeking evolves during childhood and adolescence
Assessment of MMP-9, TIMP-1, and COX-2 in normal tissue and in advanced symptomatic and asymptomatic carotid plaques
<p>Abstract</p> <p>Background</p> <p>Mature carotid plaques are complex structures, and their histological classification is challenging. The carotid plaques of asymptomatic and symptomatic patients could exhibit identical histological components.</p> <p>Objectives</p> <p>To investigate whether matrix metalloproteinase 9 (MMP-9), tissue inhibitor of MMP (TIMP), and cyclooxygenase-2 (COX-2) have different expression levels in advanced symptomatic carotid plaques, asymptomatic carotid plaques, and normal tissue.</p> <p>Methods</p> <p>Thirty patients admitted for carotid endarterectomy were selected. Each patient was assigned preoperatively to one of two groups: group I consisted of symptomatic patients (n = 16, 12 males, mean age 66.7 ± 6.8 years), and group II consisted of asymptomatic patients (n = 14, 8 males, mean age 67.6 ± 6.81 years). Nine normal carotid arteries were used as control. Tissue specimens were analyzed for fibromuscular, lipid and calcium contents. The expressions of MMP-9, TIMP-1 and COX-2 in each plaque were quantified.</p> <p>Results</p> <p>Fifty-eight percent of all carotid plaques were classified as Type VI according to the American Heart Association Committee on Vascular Lesions. The control carotid arteries all were classified as Type III. The median percentage of fibromuscular tissue was significantly greater in group II compared to group I (<it>p </it>< 0.05). The median percentage of lipid tissue had a tendency to be greater in group I than in group II (<it>p </it>= 0.057). The percentages of calcification were similar among the two groups. MMP-9 protein expression levels were significantly higher in group II and in the control group when compared with group I (p < 0.001). TIMP-1 expression levels were significantly higher in the control group and in group II when compared to group I, with statistical difference between control group and group I (p = 0.010). COX-2 expression levels did not differ among groups. There was no statistical correlation between MMP-9, COX-2, and TIMP-1 levels and fibrous tissue.</p> <p>Conclusions</p> <p>MMP-9 and TIMP-1 are present in all stages of atherosclerotic plaque progression, from normal tissue to advanced lesions. When sections of a plaque are analyzed without preselection, MMP-9 concentration is higher in normal tissues and asymptomatic surgical specimens than in symptomatic specimens, and TIMP-1 concentration is higher in normal tissue than in symptomatic specimens.</p
Hemigrammus arua, a new species of characid (Characiformes: Characidae) from the lower Amazon, Brazil
Metabolic programming of lipid profile and reproductive organs weight by leptin treatment on early life
Biological features on epibiosis of Amphibalanus improvisus (Cirripedia) on Macrobrachium acanthurus (Decapoda)
Levantamento etnobotùnico e caracterização de plantas medicinais em fragmentos florestais de Dourados-MS
Avaliação de caracterĂsticas da carcaça e da qualidade da carne de queixada (Tayassu pecari [Link, 1795])
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