Establishment of a reliable laser-Induced Choroidal Neovascularization Animal Model

Purpose: Pathologic choroidal neovascularizations (CNV) are implicated in the wet form of age-related macular degeneration (ARMD). Abnormal vessel growth is also observed in disease when hypoxia and/or inflammation occur. Our goal is to establish a standard protocol of laser-induced CNV in mice that have different levels of pigmentation to identify the most reliable animal model.Methods: CNV was induced by 4 burns around the optic disk, using a green argon laser (100μm diameter spot size; 0,05 sec. duration) in C57/Bl6, DBA/1 and Balb/c to ascertain the efficacy of the method in function of retina pigmentation. Five different intensities were tested and Bruch's membrane disruption was identified by the appearance of a bubble at the site of photocoagulation. Fluorescein angiographies (FA) were undertaken 14 days post lesion and CNV area was quantified by immunohistochemistry on cryosections.Results: CNV retina area was related to spot intensity after laser injury. While 180mW and 200mW do not induce reliable CNV (respectively 27.85��0.35% and 29��1.67% of the retina surface), 260mW is required to induce 51,07��8.52% of CNV in C57/Bl6 mice. For the DBA/1 strain, less pigmented, 200mW was sufficient to induce 49.35��3.9% of CNV, indicating that lower intensity are required to induce CNV. Furthermore, an intensity of 180mW induced greater CNV (35.55��6.01%) than in C57/Bl6 mice. Nevertheless, laser did not induce reproducible 50% CNV in Balb/c albino mice for all intensities tested. Isolectin-B4 and GFAP stainings revealed neovessel formation and photoreceptor (PR) degeneration at the impact site. The presence of glia was observed throughout all the retinal layers and angiograms showed fluorescein leakage in pigmented mice.Conclusions: The establishment of a standard protocol to induce CNV and subsequent PR degeneration is of prime importance for the use of the laser-induced CNV model and will allow to evaluate the therapeutic potency of agents to prevent CNV and retinal degeneration.

A developmental in vivo 1H NMR study in mice with genetic redox dysregulation: an animal model with relevance to schizophrenia

Glutathione (GSH), a major redox regulator and anti-oxidant, is decreased in cerebrospinal fluid and prefrontal cortex of schizophrenia patients. The gene of the key GSH-synthesizing enzyme, glutamate-cysteine ligase, modifier (GCLM) subunit, is associated with schizophrenia, suggesting that the deficit in the GSH system is of genetic origin. Using the GCLM knock-out (KO) mouse model with 60% decreased brain GSH levels, we have shown that redox dysregulation results in abnormal brain morphology and function. Current theory holds that schizophrenia is a developmental disease involving progressive anatomical and functional brain pathology. Here, we used GCLM KO mice to investigate the impact of a genetically dysregulated redox system on the neurochemical profile of the developing brain. The anterior and posterior cortical neurochemical profile of male and female GCLM KO, heterozygous and wildtype mice was determined by localised in vivo 1H NMR spectroscopy at 14.1 T (Varian/Magnex spectrometer) on post-natal days 10, 20, 30, 60 and 90. We show, for the first time, (1) that high quality 1H NMR spectra can be acquired from early developing mouse brains and (2) that recurrent anaesthesia by itself when administered at the same developmental days has no adverse effects on brain metabolites nor on adult behaviour. (3) Most importantly, our results reveal genotype and age specific changes for a number of metabolites revealing insight into normal brain development and about the impact of genetic GSH dysregulation.

The GraftConnector experience. Long-term patency and histological work up in an animal model.

BACKGROUND: A device to perform sutureless end-to-side coronary artery anastomosis has been developed by means of stent technology (GraftConnector). The present study assesses the long-term quality of the GraftConnector anastomosis in a sheep model. METHODS: In 8 adult sheep, 40-55 kg in weight, through left anterior thoracotomy, the right internal mammary artery (RIMA) was prepared and connected to the left anterior descending artery (LAD) by means of GraftConnector, on beating heart, without using any stabilizer. Ticlopidine 250 mg/day for anticoagulation for 4 weeks and Aspirin 100 mg/day for 6 months were given. The animals were sacrificed after 6 months and histological examination of anastomoses was carried out after slicing with the connector in situ for morphological analysis. RESULTS: All animals survived at 6 months. All anastomoses were patent and mean luminal width at histology was 1.8 +/- 0.2 mm; mean myotomia hyperplasia thickness was 0.21 +/- 0.1 mm. CONCLUSIONS: Long-term results demonstrate that OPCABGs performed with GraftConnector had 100% patency rate. The mean anastomotic luminal width corresponds to mean LAD's adult sheep diameter. We may speculate that myotomia hyperplasia occurred as a result of local device oversizing.

Instrumental and ethical aspects of experimental research with animal models

Experimental animal models offer possibilities of physiology knowledge, pathogenesis of disease and action of drugs that are directly related to quality nursing care. This integrative review describes the current state of the instrumental and ethical aspects of experimental research with animal models, including the main recommendations of ethics committees that focus on animal welfare and raises questions about the impact of their findings in nursing care. Data show that, in Brazil, the progress in ethics for the use of animals for scientific purposes was consolidated with Law No. 11.794/2008 establishing ethical procedures, attending health, genetic and experimental parameters. The application of ethics in handling of animals for scientific and educational purposes and obtaining consistent and quality data brings unquestionable contributions to the nurse, as they offer subsidies to relate pathophysiological mechanisms and the clinical aspect on the patient.

Um Laboratório Expedito para uma Sociedade Crioula

A descoberta de Cabo Verde n��o foi resultado de planos de pesquisa, como o caminho mar��timo para a ��ndia, nem de miss��es explorat��rias, como as que reconheceram e levantaram os litorais do continente africano. Foi um achado (1460)1 n��o previsto nas viagens mar��timas portuguesas que rapidamente se utilizou em fun����o dos objectivos principais da navega����o atl��ntica vertical: o com��rcio com a Costa de ��frica e o avan��o para o Atl��ntico Sul. Seguir-se-ia, um pouco mais tarde, c. 1520, o fornecimento de escravos ��s ��ndias de Castela navegando o Atl��ntico na horizontal. A posi����o relativa de Cabo Verde, suficientemente afastado da costa para ficar fora do alcance de ataques das popula����es africanas e convenientemente pr��ximo para facultar uma f��cil e c��moda comunica����o, viria a conferir ao arquip��lago o car��cter de ��rea estrat��gica, consignado juridicamente, com variantes, ao longo dos tempos.

A la recherche de sympt��mes de d��sorientation d��pendant d'un d��ficit d'int��gration multisensorielle chez l'animal : un ��clairage sur les m��canismes fondamentaux de la schizophr��nie

Abstract Fundamental research in psychiatric neurosciences assumes that psychiatric disorders are associated with neurobiological factors. Identification of these factors would provide therapeutic targets as well as a better understanding of the relationship between- brain and behaviour in pathological processes. We conducted experiments in an animal model of schizophrenia. Several behavioural tasks were used to evaluate spatial and working memory in these animals. The model is based on glutathione deficit during cerebral development. Indeed, a 50% decrease of glutathione has been reported in prefrontal cortex of patients with schizophrenia. Glutathione is a major antioxidant in the brain and its deficit could lead to abnormal brain connectivity. The glutathione deficit was induced in rats by perinatal (PS-P16) subcutaneous injections with Lbuthionine-(S,R)-sullfoximine (BSO), an inhibitor of glutathione synthesis. This treatment leads to a transitory 50% glutathione levels during brain development. In parallel, we conducted behavioural testing in rats with a medial prefrontal cortex lesion. This allowed us to compare early damage induced by BSO treatment with a focal lesion in adults of a brain area known to present anomalies in schizophrenia. Finally, we conducted a series of experiments in senescent rats to evaluate if cognitive deficits could be related to neurobiological changes. Our results show that an early glutathione deficit provokes cognitive deficits in adulthood. These spatial and working memory deficits resemble the cognitive deficits observed in schizophrenia. The comparison with prefrontal rats revealed that the early brain glutathione deficit provoked more severe cognitive deficits than the prefrontal lesion in adult rats. Moreover, in both cases, we observed a dissociation in memory deficits depending on the type of locomotion that was used in behavioural experiments. Indeed, BSO treated rats as well as prefrontal rats showed place learning or working memory deficits in tasks conducted on dry surfaces where they had to walk. In contrast, they showed no deficit when the same cognitive functions were tested in the water maze. This dissociation might be sustained by a difference in requirement of sensory integration between walking and swimming tasks. R��sum�� La recherche fondamentale en neurosciences psychiatriques repose sur le pr��suppos�� selon lequel les sympt��mes manifest��s dans les troubles psychiatriques auraient des concomitants neurobiologiques. Ceux-ci, une fois identifi��s, offriraient des cibles pour une d��marche th��rapeutique ainsi que des mod��les permettant de mieux comprendre les soubassements biologiques du comportement et des activit��s mentales. Nos exp��riences s'articulent autour de la question de la mod��lisation de la schizophr��nie chez l'animal. Nous avons recherch�� chez ces animaux des troubles cognitifs et sensoriels associ��s �� la schizophr��nie. En effet, chez l'homme comme chez l'animal, la m��moire spatiale et la m��moire de travail d��pendent fortement de la capacit�� d'int��gration et d'organisation des informations sensorielles. Les premi��res exp��riences ont ��t�� men��es suite �� une perturbation p��rinatale du d��veloppement c��r��bral. Celle-ci visait �� reproduire une diminution du taux de glutathion dans le cerveau, des recherches pr��c��dentes ayant observ�� une diminution de 50% du taux de glutathion dans le cortex pr��frontal de patients schizophr��nes. Le glutathion ��tant un antioxydant majeur dans le cerveau, son d��ficit pourrait conduire �� des perturbations de la circuiterie c��r��brale. Nous avons reproduit ce d��ficit chez le rat, par injection de Lbuthionine-(S,R)-sullfoximine (BSO), un inhibiteur de la synth��se du glutathion... Ce traitement a ��t�� administr�� pendant la p��riode p��rinatale (du jour postnatal 5 au jour 16) provoquant une diminution de 50% du taux de glutathion. Nous avons ensuite ��valu�� l��s r��percussions de cette atteinte pr��coce sur le comportement des rats �� l'��ge adulte. Ce mod��le s'inscrit donc dans l'hypoth��se neurod��veloppementale qui associe la schizophr��nie �� une atteinte du d��veloppement c��r��bral normal. Nous avons ensuite conduit des exp��riences similaires chez des rats ayant subi une l��sion du cortex pr��frontal pour comparer les r��percussions du traitement p��rinatal avec une l��sion, �� l'��ge adulte, d'une aire c��r��brale connue pour pr��senter des anomalies chez les patients. Finalement, nous avons ��valu�� si les processus sensoriels et cognitifs pr��c��demment ��tudi��s pouvaient ��galement ��tre affect��s lors du vieillissement normal en recherchant des corr��lats biologiques des d��ficits de m��moire li��s �� l'��ge avanc��. Nos r��sultats montrent que ce d��ficit pr��coce en glutathion peut avoir des r��percussions surale comportement �� l'��ge adulte. On a relev�� une similarit�� avec les d��ficits cognitifs associ��s.�� la schizophr��nie, incluant des d��ficits de m��moire de travail ainsi que des d��ficits de m��moire spatiale. Ces d��ficits ��taient fortement li��s au type de locomotion utilis��e et n'ont ��t�� observ��s que dans les t��ches o�� les animaux devaient rejoindre un but en marchant mais pas dans l��s tests dans lesquels ils devaient localiser une cible en nageant. Les d��ficits induits par la l��sion pr��frontale chez l'adulte ��taient beaucoup plus l��gers que ceux d��coulant de l'atteinte p��rinatale mais pr��sentaient une dissociation analogue en fonction du type de locomotion. De plus, des tests similaires men��s au cours du vieillissement confirment que la m��moire de travail peut ��tre affect��e s��lectivement par le vieillissement dans une t��che o�� les animaux doivent marcher, tout en restant intacte dans le bassin de Morris. Les d��ficits cognitifs li��s au vieillissement ��taient significativement corr��l��s �� des diff��rences de niveaux des prot��ines post-synaptiques PSD95 (postsynaptic density 95). L'ensemble des r��sultats montre que les tests qui sont fr��quemment utilis��s pour ��valuer la m��moire chez l'animal pourraient faire appel �� des processus diff��rents. Cette diff��rence pourrait notamment tenir au niveau d'int��gration sensorielle requis pour r��soudre la t��che, qui est particuli��rement sollicit��e au cours d'une locomotion intermittente.

Influ��ncia da temperatura sobre a longevidade, fecundidade e atividade hematof��gica de Aedes (Stegomyia) albopictus Skuse, 1894 (Diptera, Culicidae) sob condi����es de laboratório

Influence of temperature on longevity, fecundity, and haematophagic activity of Aedes (Stegomyia) albopictus Skuse, 1894 (Diptera, Culicidae) under laboratory condition. Based on adults of Aedes albopictus maintained under four constant temperatures, 15��C, 20��C, 25��C and 30��C, longevity of males and females, fecundity, eggs viability, number of days from emergence to the first bloodsucking, and duration of the preoviposition period were observed. The average of the longevity for female was 19.45, 59.35, 61.55 and 42.72 days, under 15��C, 20��C, 25��C and 30��C, respectively. The greatest average number of bloodsucking per female was 8.32, under 25��C. The average number of eggs per female was 1.00, 73.91, 269.87 and 183.69, and the greatest rates of viable eggs per female was 25��C and 30��C. The haematophagic activities and the oviposition were significantly influenced by temperature.

Exig��ncias t��rmicas de Aedes (Stegomyia) albopictus Skuse, 1894 (Diptera, Culicidae) em condi����es de laboratório

Thermal requirements of Aedes (Stegomyia) albopictus Skuse, 1894 (Diptera, Culicidae) under laboratory conditions. Allochtonous species of Ae. albopictus in the American continent can be found in fourteen Brazilian states - about fifteen years had been elapsed since the first report of the presence of this species in Brazilian territory. Considering its potential epidemiological importance and its adaptation to several habitats, it was determined, for this species, the threshold temperature and the thermal constant for egg, larval and pupal stages under laboratory conditions under four constant temperatures and 12:12 hours light-dark photoperiod. The threshold temperature for the egg phase and for the first instar were quite similar: 9.07 ��C (K=214.46 degree days) and 9.23 ��C (K= 36.64 degree days), respectively. For 2nd, 3rd and 4th instar, the basal-temperature was higher, oscilating between 12.26 ��C and 13.95 ��C. The threshold temperature for the complete larval stage and for the pupal stage were 12.03 ��C (K= 99.48 degree days) and 11.87 ��C (K=32.40 degree days) for males and 11.95 ��C (K=110.11 degree days) and 11.60 ��C (K=35.30 degree days) for females, respectively.

Aspectos biol��gicos de Zabrotes subfasciatus (Bohemann, 1833) (Coleoptera, Bruchidae) em Phaseolus vulgaris L., cv. Carioca (Fabaceae), sob condi����es de laboratório

Zabrotes subfasciatus is a serious pest of common beans, P. vulgaris L.. In Brazil there are several studies dealing with resistance of bean genotypes to this insect, while other studies have emphasized the utilization of oils and powders from plants to repel their attack. In this paper, fecundity, fertility, pattern of oviposition, life cycle and longevity were evaluated for a Brazilian stock from the Goi��s State on P. vulgaris cv. Carioca, at 30��C and 70% R.H. The mean fecundity was 38 eggs per female and 73% of viability. Egg laying showed an aggregated pattern. Males and females lived an average of 13 and 9 days, respectively. The total life cycle lasted for about 28 days.

Desenvolvimento de Ophyra albuquerquei Lopes (Diptera, Muscidae) em condi����es de laboratório

Ophyra albuquerquei may often be a potential predator of Musca domestica Linnaeus, 1758 in poultry and pig houses in southern Brazil. Here we address the developmental period of immatures stages and their viability. To obtain eggs, larvae and pupae, a colony was established in the laboratory. Adult flies were fed on a diet comprising two parts dry milk, two parts sugar and one part fish flour. Larval diet comprised one part fish flour and one part sawdust and water. The eggs, larvae and pupae were incubated at 26�� �� 1��C, 75% �� 10% R.H. and 12 h photoperiod. The egg to adult cycle took 573 h with a total viability of 64%. The shortest of the stages was the egg stage, which lasted about 20 h. The larval stage had the lowest viability (about 82%) and longest time interval (279 h). Overall, the results of this study show that O. albuquerquei can be readily maintained in the laboratory.