224 resultados para Juvenile hormone
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The Meriones unguiculatus (Mongolian) gerbil has demonstrated significant prostatic responses to hormonal treatments, and to drugs against human prostatic hyperplasia Spontaneous neoplasia develops in the older animals. Thirty gerbils (age 18 months) were divided into non-affected and prostatic lesion bearers and the prostate lesions were evaluated morphologically, immunohistochemically and quantitatively. The most frequent changes were in epithelial sites and, namely prostatic intraepithelial neoplasias, microinvasive carcinomas and adenocarcinomas. In the stromal compartment, cellular hyperplasia, when verified, was always associated with the sites of anomalous epithelium. Additionally, larger deposition of collagen fibrils, generating stromal fibrosis, was found in all the old gerbils analysed. The quantitative analysis showed that prostatic tissue proportions differed in altered areas, being specific for each lesion type. Isolated nuclear and nucleolar parameters were not effective in diagnosing the malign potential of lesions. However, the cellular proliferation and death indexes indicated larger cellular turnover in invasive lesions such as carcinomas. With these analyses, it could be verified that old gerbils present high propensity to develop spontaneous prostate changes and this may aid in a better understanding of the biological behaviour of human prostate cancer.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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RECAW - CNPq
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Testamos o efeito do isolamento social sobre a agressividade no peixe amazônico, Astronotus ocellatus. Dez peixes juvenis foram transferidos de um aquário de agrupamento (60 x 60 x 40 cm) contendo 15 indivíduos (sem discriminação de sexo) para um aquário de isolamento (50 x 40 x 40 cm). A agressividade foi testada por meio de ataques e exibições direcionadas à imagem do peixe no espelho. O comportamento foi filmado durante 10 min em 4 momentos: 30 min, 1 dia, 5 dias e 15 dias após o isolamento. Nós analisamos a motivação agressiva por meio da latência para início do comportamento agonístico e pela freqüência dos ataques totais e específicos direcionados ao espelho. A latência para o comportamento agonístico reduziu ao longo do isolamento e houve uma tendência de aumento da freqüência de mouth fighting (um ataque de alta intensidade de agressão), mostrando-nos um aumento na motivação agressiva. Os resultados estão de acordo com os encontrados para ciclídeos juvenís de Haplochromis burtoni, mas discordam com os encontrados para Pterophylum scalare (acará bandeira). Sugerimos que o aumento da agressividade em A. ocellatus pode ser mediado pelo efeito de exposição prévia, da residência prévia ou por processos envolvendo reconhecimento de co-específicos.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Avaliaram-se as exigências nutricionais de proteína e energia em juvenis de acará-bandeira (Pterophyllum scalare). Utilizou-se delineamento inteiramente casualizado, em esquema fatorial 3 × 2, com três níveis de proteína bruta (26, 30 e 34%), dois de energia digestível (3.100 e 3.300 kcal/kg de ração) e três repetições. Juvenis com peso médio de 2,33 ± 0,26 g foram distribuídos em aquários contendo 25 litros de água, temperatura controlada (26 ± 1ºC) e filtro biológico, na densidade de estocagem de seis animais por aquário. Os peixes foram alimentados à vontade às 9, 14 e 16h30. Na análise do desempenho produtivo, foram avaliados o peso final, o comprimento final, o ganho de peso, o consumo de ração, a conversão alimentar, a taxa de crescimento específico, a taxa de eficiência protéica e o fator de condição. As dietas contendo 26% PB proporcionaram maiores valores para taxa de eficiência protéica apenas em relação às dietas contendo 34% PB. As exigências nutricionais de proteína e energia em juvenis de acará-bandeira podem ser atendidas com dietas contendo 26% PB e 3.100 kcal ED/kg.
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Background. Ductal carcinoma in situ (DCIS) of the breast has been diagnosed increasingly since the advent of mammography. However, the natural history of these lesions remains uncertain. Ductal carcinoma in situ of the breast does not represent a single entity but a heterogeneous group with histologic and clinical differences. The histologic subtype of DCIS seems to have an influence on its biologic behavior, but there are few studies correlating subtype with biologic markers.Methods. The authors studied a consecutive series of 40 cases of DCIS and after its histologic categorization verified its relationship with ploidy using image analysis and analyzing estrogen receptor (ER), progesterone receptor (PR), p53 and c-erbB-2 expression using immunohistochemistry.Results. The three groups proposed according to the grade of malignancy were correlated significantly with some of the additional parameters studied, including aneuploidy and c-erB-2 expression. Aneuploidy was detected in 77.5% of cases of DCIS mainly in high and intermediate grade subtypes (100% and 80% vs. 35.7% in low grade) whereas immunoreactivity for c-erbB-2 was detected in 45% of cases of DCIS mainly in the high grade group. Expression of ER and PR were observed frequently in this study (63.9% and 65.7% respectively), but without correlation with the histologic subtype of DCIS, although we found a somewhat significant association between high grade DCIS and lack of ER. p53 protein expression was detected in 36.8% of these cases, but no relationship between this expression and histologic subtype or grading of DCIS was found.Conclusions. These results provide further evidence for the morphologic and biologic heterogeneity of DCIS. Besides histologic classification and nuclear grading, some biologic markers such as aneuploidy and c-erbB-2 expression constitute additional criteria of high grade of malignancy.
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Objective. To use the Pediatric Rheumatology International Trials Organization (PRINTO) core set of outcome measures to develop a validated definition of improvement for the evaluation of response to therapy in juvenile systemic lupus erythematosus (SLE).Methods. Thirty-seven experienced pediatric rheumatologists from 27 countries, each of whom had specific experience in the assessment of juvenile SLE patients, achieved consensus on 128 patient profiles as being clinically improved or not improved. Using the physicians' consensus ratings as the gold standard measure, the chi-square, sensitivity, specificity, false-positive and false-negative rates, area under the receiver operating characteristic curve, and kappa level of agreement for 597 candidate definitions of improvement were calculated. Only definitions with a kappa value greater than 0.7 were retained. The top definitions were selected based on the product of the content validity score multiplied by its kappa statistic.Results. The definition of improvement with the highest final score was at least 50% improvement from baseline in any 2 of the 5 core set measures, with no more than 1 of the remaining worsening by more than 30%.Conclusion. PRINTO proposes a valid and reproducible definition of improvement that reflects well the consensus rating of experienced clinicians and that incorporates clinically meaningful change in core set measures in a composite end point for the evaluation of global response to therapy in patients with juvenile SLE. The definition is now proposed for use in juvenile SLE clinical trials and may help physicians to decide whether a child with SLE responded adequately to therapy.
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The effect of tubero-infundibular dopaminergic neurons (TIDA) on the release of prolactin (PRL) and alpha-melanocyte stimulating hormone (alpha-MSH) was studied in median eminence-lesioned (MEL) male rats (N = 6-28). Plasma PRL and alpha-MSH levels were significantly elevated 2 (86.1 +/- 19.8 and 505.1 +/- 19.1 ng/ml), 4 (278.7 +/- 15.5 and 487.4 +/- 125.1 ng/ml), 7 (116.2 +/- 16.2 and 495.8 +/- 62.6 ng/ml) and 14 (247.3 +/- 26.1 and 448.4 +/- 63.8 ng/ml) days after MEL when compared to sham-operated control animals (55.5 +/- 13.4 and 56.2 +/- 6.1 ng/ml, respectively). MEL altered plasma PRL and alpha-MSH levels in a differential manner, with a 1.5-to 5.0-fold increase in PRL and an 8.0-to 9.0-fold increase in alpha-MSH. The increase of alpha-MSH levels occurred abruptly and remained constant from days 2 to 14. These observations indicate that TIDA plays an important role in the pituitary release of PRL and alpha-MSH and provide evidence that the release of the two hormones occurs in a differential manner.
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The objective was to determine the effect of a mouse metallothionein/bovine growth hormone transgene on resting metabolic rate (RMR), cold-induced thermogenesis, and beta-agonist stimulated nonshivering thermogenesis in mice. Non-transgenic littermates were used as controls. Open-circuit indirect calorimetry was used to assess RMR and cold-induced thermogenesis in 64 mice. Air temperature in the chamber was set at 31 degrees C for RMR and was decreased to 28, 25, 21, or 17 degrees C to determine cold-induced thermogenesis. Response to the beta-agonist isoproterenol was evaluated by monitoring changes in colonic temperature of 34 mice upon injection of the drug or saline. Despite the fact that RMR tended to be lower in transgenics than in nontransgenics, at 31 degrees C transgenic mice were able to regulate colonic temperature at the same level as nontransgenics, but colonic temperature decreased in transgenics relative to nontransgenics as air temperature was reduced. For each degree decrease in air temperature between 31 and 17 degrees C, nontransgenic mice increased heat production by 1.03 +/- .10 watt/kg, whereas transgenic mice increased it by only .56 +/- .08 watt/kg, indicating that the thermogenic response of transgenics to cold was inferior. The magnitude of the maximal increase in colonic temperature after isoproterenol injection was similar for both groups, but the response was slower in transgenics. We suggest that lean body mass and substrate availability for shivering thermogenesis are reduced in transgenics relative to total body weight, and that they allow colonic temperature to decrease to conserve energy.
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Light intensity preference of the pikeperch was tested in 1-m(2) tanks divided into four lateral compartments with a hole in the middle to allow the fish to move between compartments. Two experiments were carried out with both 0+ and 1+ pikeperch: one testing intensities from 25 to 300 lx and the other from 1 to 50 lx. Light preference was observed individually for 5 days at 8, 11, 14 and 17 h. on the first and fifth day, the preference was tested without differences in light intensity (control). In both experiments, both age groups showed preference for the lowest available light intensity. Preference for low light intensity in pikeperch may be related to innate activity and feeding behaviour and to avoidance of harmful effects of light. It is suggested that under aquaculture operations, pikeperch should be reared under very dim conditions.
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Male rats received intracerebroventricular (ICV) renin (600 ng) or daily subcutaneous injections of deoxycorticosterone (5 mg) to induce 3% NaCl and water intake. Noradrenaline (NOR; 40-160 nmol) and clonidine (CLO; 5-20 nmol) injected ICV. induced 70 to 100% inhibition of the intakes. Phenylephrine (PHE; 40-160 nmol) injected ICV induced 60 to 95% inhibition of the intakes. NOR and PHE induced a stronger inhibition on the 3% NaCl intake induced by renin than on the intake induced by deoxycorticosterone (DOC), and CLO did the opposite. CLO was always more effective than PHE to induce inhibition of the intakes. The results suggest that NOR inhibits hormone (angiotensin II, aldosterone)-induced NaCl intake by acting mainly on alpha(2)-adrenergic receptors.
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A total of 1,800 incubating eggs produced by a commercial flock of Cobb broiler breeders was used to determine the effects of storage duration (3 or 18 d) on spread of hatch and chick quality. Chick relative growth (RG) at the end of 7 d of rearing was also determined as a measure of the chick performance. Chick quality was defined to encompass several qualitative characteristics and scored according to their importance. Eggs stored for 3 d hatched earlier than those stored for 18 d (P < 0.05). Hatching was normally distributed in both categories of eggs, and the spread of hatch was not affected by storage time (P = 0.69). Storage duration of 18 d reduced the percentage of day-old chick with high quality as well as average chick quality score (P < 0.05). RG varied with length of egg storage, quality of day-old chick, and the incubation duration (P < 0.05). Eighteen-day storage of eggs not only resulted in longer incubation duration and lower quality score but also depressed RG. Chick quality as defined in this study was correlated to RG and storage time. It was concluded that day-old chick quality may be a relatively good indicator of broiler performance. The results suggest however that in order to improve performance prediction power of chick quality, it would be better to define it as a combination of several qualitative aspects of the day-old chick and the juvenile growth to 7 d.
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Background: Therapy strategies for myelodysplastic syndromes (MDS) and juvenile myelomonocytic leukemia (JMML) vary considerably. Objective: To review the treatment of Brazilian children who were diagnosed with MDS or JMML in the past decade and reported to the Brazilian Cooperative Group on Pediatric Myelodysplastic syndromes (BCG-MDS-PED). Results: of 173 children reported to the BCG-MDS-PED from January 1997 to January 2003 with a suspected diagnosis of MDS or JMML, 91 had the diagnosis confirmed after central review of the bone marrow aspirate and biopsy. Information on previous treatments was available for 78 MDS/JMML patients. Treatment varied from different schedules of low-dose (14%) and standard-dose chemotherapy (50%), granulocyte-colony-stimulating factor (G-CSF 7%), interferon (5%), steroids (2%) and erythropoietin (2%) to allogeneic stem-cell transplantation (SCT) (14%). No survival advantage could be demonstrated based on Hasle's classification or based on treatment. Conclusion: This report reflects the current practice in treating Brazilian children with MDS/JMML without specific Cooperative Group guidelines. Treatment modalities were very heterogeneous. The strategies for implementing a national protocol should consider international guidelines and focus on local experience and available resources. (C) 2004 Elsevier Ltd. All rights reserved.