Experimental Frog Virus 3 infection using Brazilian strain: amphibians susceptibility / Infecção experimental utilizando estirpe brasileira de Frog Virus 3: suceptibilidade de anfíbios

An alarming number of global warnings concerning amphibian mortality outbreaks have been released in recent years. Emerging diseases stand out as the main potential causes. Ranavirus is a worldwide-spread highly infectious disease capable of affecting even other ectothermic animals such as fish and reptiles. One major issue regarding this pathology is the lack of clinical signs before it leads up to death. Aiming at having a better understanding of anurans susceptibility, this study analyzed bullfrog (Lithobates catesbeianus) survival rate, when challenged with three doses of a Brazilian strain of Frog Virus 3 (FV3). The qPCR analysis indicated a low infectivity rate in these animals both as larvae and as adults. To elucidate the results, the following hypothesis was performed: 1) The amount of inoculum used on the frogs was insufficient to trigger an infection; 2) For the FV3 to produce clinical signs in this species, there is the need for a cofactor; 3) The animals did undergo FV3 infection but recovered in the course of the experiment, and 4) The inoculum utilized might have been low-virulence. Finally, the presence of actual clinical signs of ranavirus is discussed, with the more likely hypothesis.(AU)

Um número alarmante de notificações globais sobre surtos de mortalidade de anfíbios tem sido realizado nos últimos anos. As doenças emergentes destacam-se como as principais causas potenciais. O ranavírus é uma doença altamente infecciosa disseminada em todo o mundo, capaz de afetar até outros animais ectotérmicos como peixes e répteis. Uma questão importante em relação a essa patologia é a falta de sinais clínicos antes de levar à morte. Com o objetivo de compreender melhor a suscetibilidade dos anuros, o presente trabalho analisou a taxa de sobrevivência de rãs-touro (Lithobates catesbeianus), desafiadas com três doses de uma estirpe brasileira do Frog virus 3 (FV3). A análise de qPCR indicou baixa taxa de infectividade nesses animais, tanto como larvas quanto como adultos. Procurando esclarecer os resultados, foram formuladas as seguintes hipóteses: 1) A quantidade de inóculo aplicada nas rãs foi insuficiente para desencadear uma infecção; 2) Para que o FV3 dê sinais clínicos nesta espécie, é necessário um cofator; 3) Os animais sofreram infecção por FV3, mas se recuperaram no decorrer do experimento, e 4) O inóculo utilizado pode ter sido de baixa virulência. Finalmente, foi discutida a presença de sinais clínicos reais de ranavírus e levantada a hipótese mais provável(AU)

Association of thoracic spine deformity and cardiovascular disease in a mouse model for Marfan syndrome.

AIMS: Cardiovascular manifestations are a major cause of mortality in Marfan syndrome (MFS). Animal models that mimic the syndrome and its clinical variability are instrumental for understanding the genesis and risk factors for cardiovascular disease in MFS. This study used morphological and ultrastructural analysis to the understanding of the development of cardiovascular phenotypes of the the mgΔloxPneo model for MFS. METHODS AND RESULTS: We studied 6-month-old female mice of the 129/Sv background, 6 wild type (WT) and 24 heterozygous animals from the mgΔloxPneo model. Descending thoracic aortic aneurysm and/or dissection (dTAAD) were identified in 75% of the MFS animals, defining two subgroups: MFS with (MFS+) and without (MFS-) dTAAD. Both subgroups showed increased fragmentation of elastic fibers, predominance of type I collagen surrounding the elastic fiber and fragmentation of interlaminar fibers when compared to WT. However, only MFS animals with spine tortuosity developed aortic aneurysm/dissection. The aorta of MFS+ animals were more tortuous compared to those of MFS- and WT mice, possibly causing perturbations of the luminal blood flow. This was evidenced by the detection of diminished aorta-blood flow in MFS+. Accordingly, only MFS+ animals presented a process of concentric cardiac hypertrophy and a significantly decreased ratio of left and right ventricle lumen area. CONCLUSIONS: We show that mgΔloxPneo model mimics the vascular disease observed in MFS patients. Furthermore, the study indicates role of thoracic spine deformity in the development of aorta diseases. We suggest that degradation of support structures of the aortic wall; deficiency in the sustenance of the thoracic vertebrae; and their compression over the adjacent aorta resulting in disturbed blood flow is a triad of factors involved in the genesis of dissection/aneurysm of thoracic aorta.

Hypoglicemic and Hypolipedimic Effects of Ganoderma lucidum in Streptozotocin-Induced Diabetic Rats.

Background:Ganoderma lucidum (Leyss. Ex. Fr) Karst is a basidiomycete mushroom that has been used for many years as a food supplement and medicine. In Brazil, National Health Surveillance Agency (ANVISA) classified Ganoderma lucidum as a nutraceutical product. The objective of the present work was to observe the effects of an extract from Ganoderma lucidum in rats treated with streptozotocin, and an agent that induces diabetes. Method: Male Wistar rats were obtained from the animal lodging facilities of both University Nove de Julho (UNINOVE) and Lusiada Universitary Center (UNILUS) with approval from the Ethics Committee for Animal Research. Animals were separated into groups: (1) C: Normoglycemic control water; (2) CE: Normoglycemic control group that received hydroethanolic extract (GWA); (3) DM1 + GWA: Diabetic group that received extract GWA; and (4) DM1: Diabetic group that received water. The treatment was evaluated over a 30-day period. Food and water were weighted, and blood plasma biochemical analysis performed. Results: G. lucidum extract contained beta-glucan, proteins and phenols. Biochemical analysis indicated a decrease of plasma glycemic and lipid levels in DM rats induced with streptozotocin and treated with GWA extract. Histopathological analysis from pancreas of GWA-treated DM animals showed preservation of up to 50% of pancreatic islet total area when compared to the DM control group. In plasma, Kyn was present in diabetic rats, while in treated diabetic rats more Trp was detected. Conclusion: Evaluation from G. lucidum extract in STZ-hyperglycemic rats indicated that the extract possesses hypoglycemic and hypolipidemic activities. Support: Proj. CNPq 474681/201.

Accessing the biocompatibility of layered double hydroxide by intramuscular implantation: histological and microcirculation evaluation.

Biocompatibility of layered double hydroxides (LDHs), also known as hydrotalcite-like materials or double metal hydroxides, was investigated by in vivo assays via intramuscular tablets implantation in rat abdominal wall. The tablets were composed by chloride ions intercalated into LDH of magnesium/aluminum (Mg2Al-Cl) and zinc/aluminum (Zn2Al-Cl). The antigenicity and tissue integration capacity of LDHs were assessed histologically after 7 and 28 days post-implantation. No fibrous capsule nearby the LDH was noticed for both materials as well any sign of inflammatory reactions. Sidestream Dark Field imaging, used to monitor in real time the microcirculation in tissues, revealed overall integrity of the microcirculatory network neighboring the tablets, with no blood flow obstruction, bleeding and/or increasing of leukocyte endothelial adhesion. After 28 days Mg2Al-Cl promoted multiple collagen invaginations (mostly collagen type-I) among its fragments while Zn2Al-Cl induced predominantly collagen type-III. This work supports previous results in the literature about LDHs compatibility with living matter, endorsing them as functional materials for biomedical applications.

Liver histopathological changes in breeding bullfrogs / Alterações histopatológicas do fígado de reprodutores de rã-touro

In order to complement the histopathological study of juveniles and tadpoles of the bullfrog, Lithobathes catesbeianus, fed commercial diet used by frog farms in Rio de Janeiro, containing 40% crude protein, we performed necropsy and histopathology of the liver to establish a relationship between the quality of crude protein in the diet and animal health. For this, it was used twenty breeding male bullfrogs, with average weight 591.30 g (± 91.90 g) and length 165.02 mm (± 14.22 mm), and ten females with average weight and length of 629.80 g (± 134.47 g) and 169.32 mm (± 21.82 mm). The liver histopathology showed hyperemia, high number of elanomacrophages and cytoplasmic rarefaction, probably due to protein deficiency and fatty liver degeneration and presence of inflammatory processes. These lesions indicate a degenerative nutritional process. These findings suggest that the animals were fed with proteins of low biological value, indicating poor quality of feed, undermining the sanity. The impairment of liver function by these injuries will lead to reduced availability of precursors of sex hormones, since the liver is important in the metabolism of the same, and reproductive performance of these animals may be impaired.

Em complementação ao estudo histopatológico de girinos e imagos da rã-touro, Lithobates catesbeianus, alimentados com ração comercial utilizada pelos ranários do Rio de Janeiro, contendo 40% de proteína bruta, realizou-se necropsia e histopatologia do fígado de reprodutores, procurando uma relação entre a qualidade de proteína bruta na ração e a sanidade do animal. Foram utilizados 20 reprodutores de rã-touro, dez machos com peso de 591,30 g (± 91,90 g) e comprimento médios de 165,02 mm (± 14,22 mm), e dez fêmeas com peso e comprimento médios de 629,80 g (± 134,47 g) e 169,32 mm (± 21,82 mm). Os resultados da histopatologia mostraram que o fígado dos reprodutores, tanto machos quanto fêmeas apresentavam hiperemia, grande número de melanomacrófagos e rarefação citoplasmática provavelmente por deficiência proteica e quadro de degeneração hepática gordurosa. Tais lesões indicam quadro degenerativo nutricional. Também presente processos inflamatórios focais. Estes achados sugerem uma alimentação com proteínas de baixo valor biológico, indicando má qualidade da ração, comprometendo sua sanidade. Pode-se inferir que o comprometimento das funções hepáticas, irá diminuir a disponibilidade de precursores dos hormônios sexuais, pois o fígado é importante na metabolização dos mesmos, e a performance reprodutiva destes animais poderá ser prejudicada.

Histochemical study of fibrillar proteins of the extracellular matrix in benign and malignant mammary neoplasms in dogs

The aim of the present study was to study some of the proteins that form the extracellular matrix of 54 benign and malignant mammary neoplasms in dogs, using histochemical methods: Picrosirius and polarization microscopy for collagenous fibers, Gordon -Sweats's method for reticular fibers and Weigert's fucsine-resorcine method for elastic fibers. A large variability in quantity, distribution and characteristics of the matrix components was observed in the different types of neoplasms. Collagen type I, III and elements of the elastic system had different distribution in benign and malignant neoplasms. The simple Picrossirius method and under polarization enabled visualization of collagen as thick fibers irregularly distributed in the stroma of carcinomas and in a more orderly and regular fashion in benign neoplasms. A smaller amount of thin fibers was observed in an irregular and random disposition in carcinomas and in a regular disposition in benign neoplasms . Under polarization, the fibers present different lengths, were yellowish or reddish and strongly birefringent, what suggested that they were collagen type I and in the middle of these fibers, other ones, pale, greenish and weakly birefringent, some of them thinner, possibly collagen type III were observed. In the stroma of carcinoma, fibers were mostly thick, strongly birefringent, yellowish or reddish, disposed in an irregular and random fashion, mainly in the central areas. In condrometaplasic areas, both in malignant and benign neoplasms, there was a collagen population composed by thin fibers in a parallel disposition, limiting narrow regions where condrocytes were aligned. Around this area, there was a collagen population formed by bundles of thick anastomosed fibers, irregularly disposed in carcinomas and orderly, in a parallel fashion in benign neoplasms. Under polarization demonstrated that this population, among condrocytes, was formed by weakly birefringent fibers, pale and yellowish, what suggested a collagen type II pattern. The use of reticular fibers staining by Gordon & Sweats, enabled a visualization of collagen as thin fibers disposed not only in the dense stromas but also in the loose ones. These fibers presented variable density, but were found mainly around acini and tubules. In relation to the presence elements of the elastic system in benign and malignant tumors, it may be observed that they predominate in the malignant ones, mainly in the pseudocapsule and around acini...

Retrospective review and systematic study of mammary tumors in dogs and characteristics of the extracellular matrix

The aim of the present study was to perform a retrospective review, from 1932 to 1999, in order to establish the number of cases of mammary tumors in dogs in the records at the Pathology Department of Faculdade de Medicina Veterinária - USP, as well as the presence of desmoplasia and cartilaginous and bone metaplasia in 578 of these tumors. Among the 537 malignant tumors, 13.05 percent were simple tubular adenocarcinomas, 3.91 percent were complex tubular adenocarcinomas, 7.26 percent simple papillary adenocarcinomas, 4.28 percent complex papillary adenocarcinomas , 23.27 percent simple papillary cystadenocarcinomas ,8.37 percent complex papillary cystadenocarcinomas,16.38 percent simple solid adenocarcinomas ,6.70 percent complex solid adenocarcinomas, 2.04 percent simple spindle cell carcinomas, 1.11 percent simple spindle cell carcinomas ,2.79 percent mucinous carcinomas ,8.19 percent anaplastic carcinomas ,0.93 percent squamous carcinomas, 1.30 percent fibrosarcomas,.0.18 percent chondrosarcoma, 0.18 percent osteosarcoma and among the 41 benign tumors ,51.21 percent were adenoma, 12.19 percent papillary cystadenoma,7.31 percent papilloma, 4.87 percent cystic fibroadenoma and 24.39 percent were fibroadenoma. Both desmoplasia and metaplasia were frequent findings in benign and malignant neoplasms, but they were more frequent among complex tubular adenocarcinomas: 38 percent presented desmoplasia, 57 percent cartilaginous metaplasia and 28 percent bone metaplasia. Among the benign neoplasms, adenoma presented the more frequency: 14 percent presented desmoplasia, 29 percent cartilaginous metaplasia and 24 percent bone metaplasia. Results of this study emphasize the complexity of the inter-relationship between the macromolecules in the extracellular matrix and tumoral cells