Hepatopatia esteroidal em gatas após terapia com prednisolona: aspectos laboratoriais, tomográficos e histopatológicos / [Steroid hepatopathy in cats after prednisolone use: laboratory, tomographic, and histopathologic aspects]

Glicocorticoides são amplamente utilizados na clínica de pequenos animais, entretanto seu uso contínuo pode causar efeitos colaterais. Os gatos são considerados menos susceptíveis a esses efeitos do que outras espécies, mas existem poucos trabalhos abordando os efeitos adversos em felinos. O objetivo deste estudo foi avaliar possíveis alterações laboratoriais, histopatológicas e do grau de atenuação radiográfica do parênquima hepático de gatas submetidas à terapia com prednisolona. Um ensaio clínico foi realizado em quatro gatas hígidas, as quais receberam prednisolona, por via oral, na dose de 3mg/kg, durante 60 dias consecutivos. Nos achados histopatológicos após 60 dias de tratamento, observou-se desorganização dos cordões de hepatócitos e degeneração vacuolar, além de necrose de hepatócitos, porém não foram observados sinais de fibrose no parênquima hepático. Os dados da tomografia computadorizada demonstram aumento do grau de atenuação do parênquima hepático a partir do 30º dia da administração de prednisolona, que persistiu até o final do experimento. No presente estudo, foi possível caracterizar a existência de hepatopatia esteroidal em gatos em estágios precoces da terapia com prednisolona.(AU)

Glucocorticoids are widely used medications in small animal practice; however, its continuous use can have side effects. Cats are considered less susceptible than other species, however, the literature does not usually address adverse effects in felines. The objective of this study was to evaluate possible laboratory and histopathologic changes, as well as changes to the degree of radiographic attenuation of the hepatic parenchyma in cats treated with prednisolone. A clinical trial was done in four healthy cats, who received prednisolone orally at 3mg/kg during 60 consecutive days. In the histopathologic findings at 60 days of treatment, there were disorganized hepatocyte chords and vacuolar degeneration, as well as hepatocyte necrosis, however, there were no signs of fibrosis in the hepatic parenchyma. Data obtained via computed tomography showed increase of the degree of attenuation in the hepatic parenchyma from day 30 of prednisolone therapy, which persisted until the end of the experiment. In the present study, it was possible to characterize the existence of steroidal hepathopathy in cats in the early stages of prednisolone therapy.(AU)

Small-scale environmental enrichment and exercise enhance learning and spatial memory of Carassius auratus, and increase cell proliferation in the telencephalon: an exploratory study

Carassius auratus is a teleost fish that has been largely used in behavioral studies. However, little is known about potential environmental influences on its performance of learning and memory tasks. Here, we investigated this question in C. auratus, and searched for potential correlation between exercise and visuospatial enrichment with the total number of telencephalic glia and neurons. To that end, males and females were housed for 183 days in either an enriched (EE) or impoverished environment (IE) aquarium. EE contained toys, natural plants, and a 12-hour/day water stream for voluntary exercise, whereas the IE had none of the above. A third plus-maze aquarium was used for spatial and object recognition tests. Different visual clues in 2 of its 4 arms were used to guide fish to reach the criteria to complete the task. The test consisted of 30 sessions and was concluded when each animal performed three consecutive correct choices or seven alternated, each ten trials. Learning rates revealed significant differences between EE and IE fish. The optical fractionator was used to estimate the total number of telencephalic cells that were stained with cresyl violet. On average, the total number of cells in the subjects from EE was higher than those from subjects maintained in IE (P=0.0202). We suggest that environmental enrichment significantly influenced goldfish spatial learning and memory abilities, and this may be associated with an increase in the total number of telencephalic cells.

Microglia and neurons in the hippocampus of migratory sandpipers

The semipalmated sandpiper Calidris pusilla and the spotted sandpiper Actitis macularia are long- and short-distance migrants, respectively. C. pusilla breeds in the sub-arctic and mid-arctic tundra of Canada and Alaska and winters on the north and east coasts of South America. A. macularia breeds in a broad distribution across most of North America from the treeline to the southern United States. It winters in the southern United States, and Central and South America. The autumn migration route of C. pusilla includes a non-stop flight over the Atlantic Ocean, whereas autumn route of A. macularia is largely over land. Because of this difference in their migratory paths and the visuo-spatial recognition tasks involved, we hypothesized that hippocampal volume and neuronal and glial numbers would differ between these two species. A. macularia did not differ from C. pusilla in the total number of hippocampal neurons, but the species had a larger hippocampal formation and more hippocampal microglia. It remains to be investigated whether these differences indicate interspecies differences or neural specializations associated with different strategies of orientation and navigation.

Nanoencapsulação de um peptídeo isolado de anuros: citotoxicidade in vitro em células tumorais humanas / Nanoencapsulation of a peptide isolated from anurans: in vitro cytotoxicity in human tumor cells

A terapia antineoplásica tradicional apresenta algumas limitações que podem ser superadas através da utilização dos lipossomas. Estes nanossistemas de carreamento possibilitam o direcionamento de fármacos e reduzem efeitos secundários. Alguns peptídeos catiônicos sintetizados na pele de anuros apresentam atividade citotóxica seletiva (microorganismos e/ou tumores). Neste sentido, espécies do gênero Phyllomedusa secretam as dermaseptinas. Objetivou-se neste estudo, avaliar a citotoxicidade in vitro da dermaseptina 01 (DS 01) livre e encapsulada em lipossomas unilamelares pequenos (SUVs) em células tumorais humanas. Os lipossomas foram preparados pelo método de hidratação do filme lipídico seguido de sonicação. Foram produzidas formulações neutras e catiônicas, convencionais e furtivas. A citotoxicidade foi analisada em células tumorais de pulmão (NCI-H292), cólon (HT-29) e laringe (HEp-2), pelo ensaio de redução do sal tetrazólio (MTT) em placas de 96 poços. Os lipossomas foram submetidos a testes de estabilidade acelerada e em longo prazo. Em NCI-H292, a DS 01 livre apresentou efeito citostático médio de 35,6%. A encapsulação do peptídeo em lipossomas convencionais neutros aumentou o efeito, ao contrário dos furtivos. Para HT-29 e HEp-2, a DS 01 livre inibiu o crescimento celular em aproximadamente 50%, em média. A encapsulação em lipossomas catiônicos potencializou o efeito; os lipossomas convencionais inibiram na faixa de 80% e os furtivos, mais que 95% para as duas linhagens celulares. A DS 01, um peptídeo catiônico antimicrobiano, apresentou efeito citotóxico in vitro para células tumorais humanas que foi potencializado com a nanoencapsulação...

The conventional anticancer therapies show some limitations that can be overcome by using liposomes. This type of nanocarriers allows preferential targeting of drugs and reduces undesirable secondary effects. Some cationic peptides synthesized by the skin of anurans exhibit selective cytotoxicity (to pathogens and/or tumors). Species of Phyllomedusa secrete dermaseptins (DSs). The aim of this study was to assess the in vitro cytotoxicity of free and small unilamellar vesicle (SUV)-encapsulated dermaseptin 01 (DS 01) in various human tumor cells. Liposomes were prepared by lipid film hydration followed by sonication. Neutral and cationic, conventional and stealth liposomes were produced. Cytotoxicity was analyzed in lung (NCI-H292), colon (HT-29) and larynx (HEp-2) cancer cells, by the tetrazolium reduction method (MTT) carried out in 96-well microplates. Liposomes were tested for accelerated and long-term stability. In NCI-H292, free DS 01 showed a medium cytostatic effect of 36.5%. The conventional neutral liposome encapsulation of peptide increased this effect, whereas the stealth did not. In HT-29 and HEp-2, free DS 01 inhibited the cell growth by approximately 50% on average. The cationic liposome encapsulation was synergic, inhibition being about 80% in conventional and higher than 95% in stealth liposomes for both celllines. Thus, DS 01, an antimicrobial cationic peptide, showed in vitro cytotoxicity to human tumor cells that was potentiated by nanoencapsulation...

Evaluation of the antischistosomal activity of sulfated α-D-glucan from the lichen Ramalina celastri free and encapsulated into liposomes

The antischistosomal activity of the sulfated polysaccharide α-D-glucan (Glu.SO4) extracted from Ramalina celastri was evaluated after encapsulation into liposomes (Glu.SO4-LIPO) in Schistosoma mansoni-infected mice. The effect of treatment with Glu.SO4 and Glu.SO4-LIPO (10 mg/kg) on egg elimination, worm burden and hepatic granuloma formation was assessed using female albino Swiss mice, 35-40 days of age, weighing 25 ± 2 g, infected with 150 cercariae/animal (Biomphalaria glabrata, BH strain). Four groups (N = 10) were studied, two controls (empty liposomes and NaCl) and two treated groups (Glu.SO4-LIPO and Glu.SO4) using a single dose. Parasitological analysis revealed that Glu.SO4-LIPO was as efficient as Glu.SO4 in reducing egg elimination and worm burden. Treatment with free Glu.SO4 and Glu.SO4-LIPO induced a statistically significant reduction in the number of granulomas (62 and 63 percent, respectively). Lectin histochemistry showed that wheat germ agglutinin intensely stained the egg-granuloma system in all treated groups. On the other hand, peanut agglutinin stained cells in the control groups, but not in the treated groups. The present results suggest a correlation between the decreasing number of hepatic egg-granulomas and the glycosylation profile of the egg-granuloma system in animals treated with free Glu.SO4 or Glu.SO4-LIPO.

Does usnic acid affect microtubules in human cancer cells? / O ácido úsnico pode afetar microtúbulos em células cancerosas humanas?

Usnic acid, a lichen metabolite, is known to exert antimitotic and antiproliferative activities against normal and malignant human cells. Many chemotherapy agents exert their activities by blocking cell cycle progression, inducing cell death through apoptosis. Microtubules, protein structure involved in the segregation of chromosomes during mitosis, serve as chemotherapeutical targets due to their key role in cellular division as well as apoptosis. The aim of this work was to investigate whether usnic acid affects the formation and/or stabilisation of microtubules by visualising microtubules and determining mitotic indices after treatment. The breast cancer cell line MCF7 and the lung cancer cell line H1299 were treated with usnic acid 29 µM for 24 hours and two positive controls: vincristine (which prevents the formation of microtubules) or taxol (which stabilizes microtubules). Treatment of MCF7 and H1299 cells with usnic acid did not result in any morphological changes in microtubules or increase in the mitotic index. These results suggest that the antineoplastic activity of usnic acid is not related to alterations in the formation and/or stabilisation of microtubules.

O ácido úsnico, um metabólito de liquens, é conhecido por sua atividade antimitótica e antiproliferativa em células humanas normais e malignas. Muitos quimioterápicos exercem suas atividades bloqueando a progressão do ciclo celular e induzindo morte celular por apoptose. Os microtúbulos, estruturas protéicas envolvidas na segregação dos cromossomos durante a mitose, servem como alvo quimioterapêutico devido ao seu importante papel tanto na divisão celular quanto nos mecanismos de morte celular por apoptose. O objetivo deste trabalho foi investigar se o ácido úsnico afeta a formação e/ou estabilização dos microtúbulos, a partir da visualização de microtúbulos e determinação de índices mitóticos após o tratamento. Células de câncer de mama MCF7 e de câncer de pulmão H1299 foram tratadas por 24 horas com 29 µM de ácido úsnico e dois controles positivos: vincristina (que impede a formação de microtúbulos) e taxol (que estabiliza microtúbulos). O tratamento das células MCF7 e H1299 com o ácido úsnico não resultou em aumento do índice mitótico. Os resultados sugerem que a atividade antineoplásica do ácido úsnico não está relacionada a alterações na formação e/ou estabilização de microtúbulos.

A cura de objetivo minimo. Uma experiencia em psicoterapia breve na adolescencia. / The cure of minimal objective. An experience in brief psychotherapy in adolescence

O presente trabalho foi realizado pela equipe do setor de adolescentes do Instituto de Psiquiatria da UFRJ. A ideologia do setor e ter uma equipe de profissionais treinados para atender a imperiosa demanda das diversas patologias da populacao que acorre a instituicao. Para isto, desenvolve um amplo espectro de tecnicas de atendimento: psicoterapia breve individual, psicoterapia breve de grupo, psicoterapia familiar breve, co-terapia, psicofarmacoterapia etc. O objetivo principal desta comunicacao e apresentar um pequeno modelo empirico, instrumentado na psicoterapia breve da adolescencia. Deste ponto de vista, tenta-se demonstrar que uma das dificuldades para o trabalho clinico reside em uma serie de ideias preconcebidas, que obstaculizam as tarefas assistenciais. Estas ideias funcionam como mitos, que impedem ou atrapalham o desenvolvimento da psicoterapia. Desenham-se alguns destes mitos, e se tenta ilustrar, mediante tres casos clinicos, o que nos chamamos de "cura de objetivo minimo" (C.O.M.).Esta cura de objetivo minimo consiste em tentar resolver, mediante abordagens multivariadas de ordem empirica que se vao apresentando.Neste sentido, o trabalho pretende mostrar que a resolucao de qualquer resistencia ou obstaculo ao tratamento e uma cura minima.resolucao de qualquer resistencia ou obstaculo ao tratamento e uma cura minima