Oxidative stress in rats experimentally infected by Sporothrix schenckii.

The aim of this study was to evaluate whether oxidative stress occurs in rats experimentally infected by Sporothrix schenckii, and its possible effect on disease pathogenesis. Thirty rats were divided into two groups: the group A (uninfected, n = 18) and the group B (infected by S. schenckii, n=21). Blood samples were collected on days 15, 30 and 40 post-infection (PI). At each sampling time, six rats of the group A, and seven of the group B were bled. TBARS (thiobarbituric acid reactive substances) levels in serum samples were measured to evaluate lipid peroxidation. In addition, catalase (CAT) and superoxide dismutase (SOD) activities, known as biomarkers of antioxidants levels, were verified in whole blood. Seric pro-inflammatory cytokine levels were measured (IFN-γ, TNF-α, and IL-6), which showed that these inflammatory mediators were at higher levels in the infected rats (P < 0.001). In comparison to uninfected animals, rats with sporotrichosis showed significantly higher (p < 0.01) levels of TBARS on day 40 PI; CAT activity was significantly increased (p < 0.01) on days 30 and 40 PI; and SOD activity was increased (p < 0.01) on day 40 PI. Infected rats showed larger testicles and granulomas in the testicular capsule, as well as hepatic granulomas and splenic follicular hyperplasia. All tissues (testicle, spleen, and liver) showed inflammation associated with numerous fungal structures. These results demonstrated that the intense inflammatory response (seric and tissue) in sporotrichosis is a likely mechanism for redox imbalance, and consequently cause the oxidative stress in experimentally infected rats.

Cholinergic enzymes and inflammatory markers in rats infected by Sporothrix schenckii.

The aim of this study was to evaluate the cholinesterase activity in serum, whole blood, and lymphocytes, as well as to verify its relation to immune response in rats experimentally infected by Sporothrix schenckii. For this study, 63 Wistar rats (Rattus norvegicus), male, adult were divided into three groups: the negative control group (GC: n = 21), the group infected subcutaneously (GSC: n = 21), and the group infected intraperitoneally (GIP: n = 21). The groups were divided into subgroups and the following variables were evaluated at 15, 30, and 40 days post-infection (PI): acetylcholinesterase (AChE) activity in lymphocytes and whole blood, butyrylcholinesterase (BChE) activity in serum, cytokines levels (IL-1, IL-6, TNFα, and INF-γ), immunoglobulins levels (IgA, IgG, IgM, and IgE), and protein profile by electrophoresis. Both infected groups showed increased levels of inflammatory parameters (P < 0.05) in tissue and inflammatory infiltrates. The activities of AChE in lymphocytes and BChE in serum increased (P < 0.05) significantly in animals from the GSC group on day 40 PI compared to the GC group. Regarding the GIP, there was a marked increase in the AChE activity in lymphocytes on days 30 and 40 PI, and in whole blood on days 15, 30, and 40 PI compared to GC. Furthermore, IL-10, an anti-inflammatory cytokine, was also present in high levels during chronic systemic S. schenckii infections in animals. Therefore, it is concluded that cholinesterase has an important modulatory role in the immune response during granulomatous infection by S. schenckii.

Oxidative stress parameters in blood, liver, and kidney of diabetic rats treated with curcumin and/or insulin.

This study evaluated the effects of curcumin and/or insulin on antioxidant enzyme activity in blood, liver, and kidney, as well as on lipid peroxidation and delta aminolevulinic dehydratase (δ-ALA-D) activity, and a histopathological analysis of streptozotocin-induced diabetic rats. The animals were divided into six groups (n = 6): control/saline (C); control/curcumin (CCur); diabetic/saline (D); diabetic/insulin (DIns); diabetic/curcumin (DCur); and diabetic/insulin/curcumin (DInsCur). After 30 days of treatment with curcumin and/or insulin, the animals were sacrificed and the liver, kidney, and serum were used for experimental determinations. Results of histopathological analysis showed that the treatment with insulin ameliorate renal and hepatic lesions from both DIns and DInsCur groups. TBARS levels were significantly increased in serum, liver, and kidney in D group and the administration of curcumin and insulin prevented this increase in DIns and DCur groups. The activities of catalase (CAT), superoxide dismutase, and δ-ALA-D presented a significant decrease in the liver and kidney D group when compared to C group (P < 0.05). The animals treated with curcumin and insulin presented an increase of CAT activity, revealing a positive interaction between both substances. The treatments with curcumin or insulin prevented oxidative stress in blood, through modulation of enzymatic antioxidant defenses. These findings contributed to the comprehension that antioxidants from medicinal plants could be used as adjuvant in the treatment of this endocrinopathy and not as single therapy.

Trypanosoma evansi: Ca(2+) ATPase activity and lipid peroxidation in skeletal muscle from rats experimentally infected.

The aim of this study was to evaluate Ca(2+) ATPase activity and the lipid peroxidation in muscles from rats experimentally infected by Trypanosoma evansi and its roles in the muscle pathogenesis in trypanosomosis. Thirty-six rats were divided in two groups. Group A was infected with an isolate from T. evansi and group B was used as a negative control. Group A was divided into three subgroups (A1, A2 and A3), three animals each group, as well as group B (B1, B2 and B3). The collection of samples were performed at days 5 (A1 and B1), 15 (A2 and B2) and 30 (A3 and B3) post-infection (PI) with the purpose of comparison between healthy and infected rats in the course of the disease. The Ca(2+) ATPase enzyme activity was determined in skeletal muscle samples. Muscle tissue lipid peroxidation was determined by TBARS levels, and histopathologically it was investigated a possible damage to the muscle tissue of rats infected with T. evansi. It was observed a significant decrease of Ca(2+) ATPase activity in infected rats compared to not-infected. This enzymatic inhibition was observed at days 5, 15 and 30 PI. A significant increase was observed for TBARS levels in the muscles of infected rats at days 5, 15 and 30 PI. It was not identified any histological alterations for gastrocnemius in rats infected by T. evansi at days 5 and 15 PI. Nevertheless, at day 30 PI it was verified inflammatory infiltrate with mononuclear cells between muscle fibers in three infected rats (50%). T. evansi infections in rats showed a negative correlation between Ca(2+) ATPase and TBARS levels. Based on these results we suggest that the leg weakness and muscle injuries common in infected animals with T. evansi may be related to a reduced activity of Ca(2+) ATPase and oxidative stress.

Pre-treatment with ebselen and vitamin E modulate acetylcholinesterase activity: interaction with demyelinating agents.

The ethidium bromide (EB) demyelinating model was associated with vitamin E (Vit E) and ebselen (Ebs) treatment to evaluate acetylcholinesterase (AChE) activity in the striatum (ST), hippocampus (HP), cerebral cortex (CC) and erythrocytes. Rats were divided into seven groups: I-Control (saline), II-(canola); III-(Ebs), IV-(Vit E); V-(EB); VI-(EB+Ebs) and VII-(EB+Vit E). At 3 days after the EB injection, AChE activity in the CC and HC was significantly reduced in groups III, IV, V, VI and VII (p<0.05) and in the ST it was reduced in groups III and V (p<0.05) when compared to the control group. At 21 days after the EB injection, AChE activity in the CC was significantly reduced in groups III, IV and V, while in groups VI and VII a significant increase was observed when compared to the control group. In the HC and ST, AChE activity was significantly reduced in groups V, VI and VII when compared to the control group (p<0.05). In the erythrocytes, at 3 days after the EB injection, AChE activity was significantly reduced in groups III, IV, V, VI and VII and at 21 days there was a significant reduction only in groups VI and VII (p<0.05) when compared to the control group. In conclusion, this study demonstrated that Ebs and Vit E interfere with the cholinergic neurotransmission by altering AChE activity in the different brain regions and in the erythrocytes. Furthermore, treatment with Vit E and Ebs protected against the demyelination lesion caused by EB. In this context, we can suggest that ebselen and Vit E should be considered potential therapeutics and scientific tools to be investigated in brain disorders associated with demyelinating events.

Cyclosporine A inhibits acetylcholinesterase activity in rats experimentally demyelinated with ethidium bromide.

Cyclosporine A is the major immunosuppressive agent used for organ transplantation and for the treatment of a variety of autoimmune disorders such as multiple sclerosis. In this work, we investigated the effect of the cyclosporine A on the acetylcholinesterase activity in the cerebral cortex, striatum, hippocampus, hypothalamus, cerebellum and pons of the rats experimentally demyelinated by ethidium bromide. Rats were divided into four groups: I control (injected with saline), II (treated with cyclosporine A), III (injected with 0.1% ethidium bromide) and IV (injected with 0.1% the ethidium bromide and treated with cyclosporine A). The results showed a significant inhibition (p<0.05) of acetylcholinesterase activity in the groups II, III and IV in all brain structures analyzed. In the striatum, hippocampus, hypothalamus and pons the inhibition was greater (p<0.005) when ethidium bromide was associated with cyclosporine A. In conclusion, the present investigation demonstrated that cyclosporine A is an inhibitor of acetylcholinesterase activity and this effect is increased after an event of toxic demyelination of the central nervous system.

Previous treatment with ebselen and vitamin E alters adenine nucleotide hydrolysis in platelets from adult rats experimentally demyelinated with ethidium bromide.

Many aspects of the relationship between the demyelinating pathology and platelet function need to be elucidated. Thus, the activity of NTPDase and 5'-nucleotidase enzymes was analyzed in platelets from rats demyelinated with ethidium bromide (EB) and previously treated with ebselen (Ebs) and vitamin E (Vit. E). The animals were divided into four groups: for ebselen, the groups were: I-control (saline), II-(saline and Ebs), III-(EB) and IV-(EB and Ebs); and for vitamin E, the groups were: I - control (saline), II-(saline and Vit. E), III-(EB) and IV-(EB and Vit. E). After 3 and 21 days, the blood was collected and the platelets were separated for enzymatic assays. For the treatment with Ebs, the NTPDase activity for ATP substrate was significantly lower in groups II, III and IV (p < 0.05) after 3 days, while after 21 days, a reduction was observed in group III (p < 0.05). ADP hydrolysis was reduced in group II (p < 0.05) and increased in group IV (p < 0.05) after 3 days, while after 21 days there was an increase in group IV (p < 0.05). In the treatment with Vit. E, ATP hydrolysis was lower in groups II, III and IV (p < 0.05) after 3 and 21 days. ADP hydrolysis was increased in group II (p < 0.05) after 3 days, and in group IV (p < 0.05) after 21 days. However, 5'-nucleotidase activity was not altered by the treatments. These findings demonstrate that NTPDase activity in platelets is diminished in demyelinating events and the treatments with Ebs and Vit. E modulated adenine nucleotide hydrolysis.

Effect of lycopene on nephrotoxicity induced by mercuric chloride in rats.

Oxidative stress is an important molecular mechanism for kidney injury in mercury poisoning. We studied lycopene, a potent carotenoid found in tomatoes due to its large antioxidant properties, and also evaluated the ability of lycopene to prevent HgCl(2) nephrotoxicity. Rats were injected with HgCl(2) (0 or 5 mg/kg body weight, subcutaneously) 6 hr after lycopene administration (0, 10, 25 or 50 mg/kg by gavage) and were killed 12 hr after HgCl(2) exposure. HgCl(2)-induced inhibition of delta-aminolevulinate dehydratase activity (approximately 35%) and increase of lipid peroxidation in kidney (approximately 37%) were prevented by lycopene. However, lycopene did not prevent the increase of plasma creatinine levels (approximately 123%) and renal tubular necrosis induced by HgCl(2). Glutathione peroxidase and catalase activities were enhanced (approximately 71% and approximately 41%), while superoxide dismutase activity was depressed (approximately 44%) in HgCl(2)-treated rats when compared to control and these effects were prevented by lycopene. Our results indicate that although lycopene did not prevent HgCl(2)-induced renal failure, it could play a beneficial role against HgCl(2) toxicity by preventing lipid peroxidation and changes in the activity of delta-aminolevulinate dehydratase and antioxidant enzymes.

Ethidium bromide inhibits rat brain acetylcholinesterase activity in vitro.

Ethidium bromide (EtBr), a fluorescent dark red compound and stain for double-stranded DNA and RNA was used to study acetylcholinesterase (AChE) activity in vitro together with kinetic parameters of this enzyme in the striatum (ST), hippocampus (HP), cerebral cortex (CC) and cerebellum (CB) of adult rats. AChE activity in vitro in the ST, HP, CC and CB was significantly reduced (p<0.05) in the presence of EtBr at concentrations of 0.00625, 0.0125, 0.025, 0.05 and 0.1 mM. For the analysis of the kinetic three concentrations of EtBr were tested (0.00625, 0.025 and 0.1 mM). An uncompetitive inhibition type was observed in the ST, HP and CC, whereas in the CB the inhibition type was mixed. These data indicate that EtBr should be considered a strong inhibitor of AChE activity demonstrating that there is an interaction between this compound and the cholinergic system.

Sub-chronic administration of diphenyl diselenide potentiates cadmium-induced testicular damage in mice.

Sub-chronic cadmium (Cd) exposure causes testicular damage in mice. The mode of action may involve oxidative stress and especially lipid peroxidation. The present study has monitored the pathogenesis of testicular damage during sub-chronic Cd exposure and has evaluated the potential protective effect of antioxidant therapy with diphenyl diselenide (PhSe)(2). Male mice were dosed with 2.5 mg/kg CdCl(2) (2.5 mg/kg) with or without (PhSe)(2) (5 micromol/kg) at 30 min post-exposure using a model of five weekly subcutaneous injections. Histological evaluation of the testis was performed across a 4 week test period. Animals exposed to CdCl(2) and CdCl(2) plus (PhSe)(2) displayed a reduction in body weight gain and testicular weight. Progressive damage and histolopathological changes in the testis were not remedied with, but rather were potentiated by, (PhSe)(2) therapy. We conclude that (PhSe)(2) enhances testicular injury in an animal model for sub-chronic Cd exposure mice.

Ultrastructure of canine meninges after repeated epidural injection of S(+)-ketamine.

BACKGROUND: The safety of ketamine when administered by the spinal route must be confirmed in various animal species before it is approved for use in humans. This study evaluates the ultrastructure of canine meninges after repeated doses of epidural S(+)-ketamine. METHODS: Five dogs received S(+)-ketamine 5%, 1 mg/kg, twice a day for 10 days through an epidural catheter with its tip located at the L5 level. One dog received the same volume of normal saline at the same times. The spinal cord and meninges were processed for histopathological and ultrastructural studies. Clinical effects were assessed after each injection. RESULTS: Motor and sensory block appeared after each injection of S(+)-ketamine, but not in the dog receiving saline. No signs of clinical or neurologic alterations were observed. Using light microscopy, no meningeal layer showed alterations except focal infiltration at the catheter tip level by macrophages, lymphocytes, and a few mast cells. The cells of different layers were studied by electron microscopy and interpreted according to data from human and other animal species because no ultrastructural description of the canine meninges is currently available. There were no cellular signs of inflammation, phagocytosis, or degeneration in meningeal layers and no signs of atrophy, compression, or demyelinization in the areas of dorsal root ganglia and spinal cord around the arachnoid. These findings were common for dogs receiving S(+)-ketamine and the dog receiving saline. CONCLUSION: Repeated doses of epidural S(+)-ketamine 5%, 1 mg/kg, twice a day for 10 days was not associated to cellular alterations in canine meninges.

The effects of free fat graft or cellulose membrane implants on laminectomy membrane formation in dogs.

The purpose of this study was to determine the effect of cellulose membrane or free fat grafts (FFG) on laminectomy membrane (LM) formation. Eighteen dogs were randomly divided into three groups of six dogs. All dogs underwent a modified dorsal laminectomy on T(13)-L(1). The laminectomy defect was left uncovered in the control group but either a FFG or a cellulose membrane implant was provided in the other two groups. The dogs were evaluated through neurological examination, myelography, macroscopic roundness index of spinal cord and histological evaluations of epidural fibrosis and spinal cord. The results showed a significant difference between the control and the FFG group, with the FFG causing neurological deficits and spinal cord compression as assessed by the roundness index of the spinal cord. Both FFG and cellulose membrane were partially effective in preventing LM formation. The use of FFG was associated with a high rate of significant neurological complications and spinal cord lesions.

Neuroprotective role of quercetin in locomotor activities and cholinergic neurotransmission in rats experimentally demyelinated with ethidium bromide.

AIM: The purpose of this study was to investigate whether the flavonoid quercetin can prevent alterations in the behavioral tests and of cholinergic neurotransmission in rats submitted to the ethidium bromide (EB) experimental demyelination model during events of demyelination and remyelination. MAIN METHODS: Wistar rats were randomly distributed into four groups (20 animals per group): Control (pontine saline injection and treatment with ethanol), Querc (pontine saline injection and treatment with quercetin), EB (pontine 0.1% EB injection and treatment with ethanol), and EB+Querc (pontine 0.1% EB injection and treatment with quercetin). The groups Querc and Querc+EB were treated once daily with quercetin (50mg/kg) diluted in 25% ethanol solution (1ml/kg) and the animals of the control and EB groups were treated once daily with 25% ethanol solution (1ml/kg). Two stages were observed: phase of demyelination (peak on day 7) and phase of remyelination (peak on day 21 post-injection). Behavioral tests (beam walking, foot fault and inclined plane test), acetylcholinesterase (AChE) activity and lipid peroxidation in pons, cerebellum, hippocampus, hypothalamus, striatum and cerebral cortex were measured. KEY FINDINGS: The quercetin promoted earlier locomotor recovery, suggesting that there was demyelination prevention or further remyelination velocity as well as it was able to prevent the inhibition of AChE activity and the increase of lipidic peroxidation, suggesting that this compound can protect cholinergic neurotransmission. SIGNIFICANCE: These results may contribute to a better understanding of the neuroprotective role of quercetin and the importance of an antioxidant diet in humans to provide benefits in neurodegenerative diseases such as MS.

Clinical signs and histopathology of brain, spinal cord and muscle of the pelvic limb of rats experimentally infected with Trypanosoma evansi.

The aim of this study was to investigate whether rats infected with Trypanosoma evansi had neurological and locomotor signs, as well as histological lesions in the central nervous system (CNS) and pelvic muscles. To carry out this study, 52 rats were used and divided into two groups. The animals in Group A (n=40) were infected with T. evansi, and the rats in Group B (n=12) were used as negative controls (non-infected). Neurological examination was performed at Days 5, 15, 30 and 150 post-infection (PI) with eventual euthanasia of the rats. Samples of brain, spinal cord and skeletal muscle (biceps femoris and gastrocnemius muscles) were collected. The neurological tests evaluated motor capacity, balance and pain sensitivity. At Day 5 PI in Subgroup A1, the rats showed high parasitemia, became apathetic and presented with slow movements and signs of disorientation. After Day 15 PI in Subgroup A2 and Day 30 PI in Subgroup A3, no more clinical abnormalities were observed. Histologically, there was no damage to the CNS in these three subgroups, but within Subgroup A3, mononuclear infiltration of the muscle was observed. Rats chronically infected (Subgroup A4 - Day 150 PI) showed muscle atrophy, walking dysfunction and paralysis of the hind limbs. Mild mononuclear inflammatory infiltrates and perivascular cuffs were observed in the CNS of some of the animals in Subgroup A4. In these rats, severe muscle damage was observed in the skeletal muscle which included atrophy and loss of muscle fibers, multinucleated giant muscle cells, mononuclear myositis, Wallerian degeneration of the innervating fibers and mononuclear inflammatory infiltrate in the perineurium and adipose tissue. Based upon these findings, we conclude that infection by T. evansi in rats leads to muscle damage, which is probably the cause of the paralysis of hind limbs.

Glial cells of the central nervous system of Bothrops jararaca (Reptilia, Ofidae): an ultrastructural study / Células gliais do sistema nervoso central de Bothrops jararaca (Reptilia, Ofidae): um estudo ultraestrutural

Although ultrastructural characteristics of mature neuroglia in the central nervous system (CNS) are very well described in mammals, much less is known in reptiles, especially serpents. In this context, two specimens of Bothrops jararaca were euthanized for morphological analysis of CNS glial cells. Samples from telencephalon, mesencephalon and spinal cord were collected and processed for light and transmission electron microscopy investigation. Astrocytes, oligodendrocytes, microglial cells and ependymal cells, as well as myelin sheaths, presented similar ultrastructural features to those already observed in mammals and tended to maintain their general aspect all over the distinct CNS regions observed. Morphological similarities between reptilian and mammalian glia are probably linked to their evolutionary conservation throughout vertebrate phylogeny...

Muito embora as características ultraestruturais da neuróglia madura do sistema nervoso central (SNC) sejam bem descritas em mamíferos, muito pouco é conhecido em répteis, especialmente em serpentes. Neste contexto, dois espécimes de Bothrops jararaca foram eutanasiados para análise morfológica das células gliais presentes no SNC. Amostras de telencéfalo, mesencéfalo e medula espinhal foram coletadas e processadas para investigação por microscopia de luz e eletrônica de transmissão. Astrócitos, oligodendócitos, células microgliais e ependimárias, bem como bainhas de mielina, apresentaram características ultraestruturais similares àquelas já observadas em mamíferos e tenderam a manter seu aspecto geral pelas diferentes regiões observadas no SNC. Similaridades morfológicas entre as células gliais de mamíferos e de répteis estão provavelmente ligadas a sua conservação evolutiva ao longo da filogenia dos vertebrados...

Effect of vitamin E on ectonucleotidase activities in synaptosomes and platelets and parameters of oxidative stress in rats experimentally demyelinated.

NTPDase and 5'-nucleotidase activities in synaptosomes and platelets and oxidative stress parameters, such as TBARS levels, non-protein thiols and catalase activity were analyzed in rats submitted to demyelination by ethidium bromide (EB) and treated with vitamin E. The following groups were studied: I control (saline); II (canola oil); III (vitamin E); IV (EB) and V (EB and vitamin E). 2mg/kg of vitamin E were injected intraperitoneally in animals from groups III and V for seven days. After this time, the animals were submitted to euthanasia and samples were collected for biochemical assays. The results showed that NTPDase and 5'-nucleotidase activities were significantly increased in synaptosomes and platelets of rats from group IV when compared with the groups I, II, III and V (p<0.05). When demyelinated rats were treated with vitamin E (group V), NTPDase activity in synaptosomes and platelets was reduced to control level, while 5'-nucleotidase activity was significantly increased in relation to the control group (p<0.05). TBARS levels and non-protein thiols were significantly increased in group IV (p<0.05), while catalase activity was significantly decreased in this group when compared with the control group (p<0.05). No differences in TBARS levels, non-protein thiols and catalase activity were observed in groups I, II, III and V. These findings demonstrate that ectonucleotidase activities in synaptosomes and platelets and some parameters of oxidative stress were altered after a demyelinating event on the nervous system and that treatment with vitamin E modulated adenine nucleotide hydrolysis and altered oxidative stress parameters in this experimental condition.

Harpejamento em eqüinos no Rio Grande do Sul / Stringhalt in horses from the state of Rio Grande do Sul, Brazil

São relatados a epidemiologia, os sinais clínicos e aspectos macro e microscópicos de casos de harpejamento ocorridos de 2000 a 2005 em eqüinos de oito propriedades rurais de seis municípios do Rio Grande do Sul. Pelo menos 10 eqüinos foram afetados, com idades variando entre 1 e 13 anos (média de 6,2 anos) e 1-2 eqüinos foram afetados por propriedade. Dentre os fatores que podem ter influenciado o aparecimento da doença está incluída a escassez de forragem devido à seca. A presença da planta Hypochaeris radicata, freqüentemente implicada como causa de harpejamento em eqüinos, foi observada na pastagem de três entre cinco propriedades onde a ocorrência dessa planta foi investigada; em seis dessas propriedades a forragem era pouca devido à falta de chuva. A morbidade foi estimada em 17,3 por cento e a letalidade foi perto de zero, embora dois eqüinos tenham sido submetidos à eutanásia para serem necropsiados. Os sinais clínicos característicos incluiam hiperflexão dos membros pélvicos, dificuldade de caminhar e andar com saltos tipo pulos de coelho. Foi feita uma graduação da intensidade dos sinais clínicos em um escore de números de 1 a 5, os números mais altos indicando um grau de intensidade maior. Três eqüinos foram graduados como 1, um eqüino como 2, três eqüinos como 3, um eqüino como 4 e dois eqüinos como 5. O tratamento com fenitoína em dois eqüinos e com fenitoína associada a tenectomia em um outro não resultou em melhora do quadro clínico. Quatro dos 10 cavalos com harpejamento examinados clinicamente se recuperaram sem tratamento após uma doença clínica com evolução de 2-4 meses e quatro cavalos não se recuperaram mesmo após 9-17 meses de doença clínica, quando foram examinados pela última vez. Os achados de necropsia incluíam atrofia dos músculos esqueléticos das grandes massas musculares, confirmada histologicamente. A avaliação histológica dos nervos periféricos de um eqüino afetado submetido à eutanásia revelou redução ou ausência ...

The epidemiology, clinical, gross and histological findings of cases of stringhalt occurring in horses from eight farms in six counties in the State of Rio Grande do Sul, Brazil from 2000-2005 are reported. At least 10 horses were affected. Ages of affected horses were 1-13 years (average 6.2 years) and 1-2 horses were affected in each farm. Factors that might have influenced the appearance of the disease included dearth of forage due to insufficient rainfall. The presence of the plant Hypochaeris radicata, often implicated as a cause of stringhalt in horses, was observed in the pasture of three out of five evaluated farms and in six of these farms the pasture was poor due to scarse precipitation. Estimated morbidity was 17.3 percent and lethality was close to zero although two horses were euthanatized for necropsy. Characteristic clinical signs included excessive flexion of the stifle and hock joints, impaired ambulation and bunny hop-type of gait. Clinical disease was graded by number scores from 1-5, higher numbers indicating increasing severity. Three horses were graded as 1, one horse as 2, three horses as 3, one horse as 4 and two horses as 5. Treatment with phenytoin in two horses and with phenytoin and tenectomy in another one did not result in amelioration of the clinical signs. Four out of ten clinical examined horses with stringhalt recovered with no treatment within 2-4 months of clinical disease and four affected horses did not recover even after 9-17 months of clinical disease, when they were lastly examined. Necropsy findings included atrophy of skeletal muscle of the large muscular groups which was confirmed histologically. Histological evaluation of peripheral nerves of one of the euthanatized horses revealed reduction or absence of myelinated fibers. Ultrastructural findings included signs of demyelination, regeneration and remyelination of peripheral nerves.

Causas de morte e razões para eutanásia de cães da Mesorregião do Centro Ocidental Rio-Grandense (1965-2004) / Causes of death and reasons for euthanasia in dogs from the midland region of the Midwest of Rio Grande do Sul State, Brazil (1965-2004)

Este estudo teve como objetivo principal determinar a prevalência das doenças que culminam em morte ou que fazem com que os cães da Mesorregião do Centro Ocidental Rio-Grandense sejam submetidos à eutanásia. Para isso, foram revisados todos os protocolos de necropsia de cães, arquivados no Laboratório de Patologia Veterinária (LPV) da Universidade Federal de Santa Maria (UFSM), realizadas entre janeiro de 1965 e dezembro de 2004. Nos arquivos do LPV-UFSM foram encontrados 4.844 protocolos de necropsia de cães. A distribuição dos casos em relação às categorias de doenças diagnosticadas foi a seguinte: doenças infecciosas e parasitárias (1.693 [35,0 por cento]), neoplasmas (378 [7,8 por cento]), distúrbios causados por agentes físicos (369 [7,6 por cento]), doenças degenerativas (342 [7,1 por cento]), intoxicações e toxiinfecções (112 [2,3 por cento]), eutanásia por conveniência (101 [2,1 por cento]), doenças metabólicas e endocrinológicas (97 [2,0 por cento]), distúrbios iatrogênicos (83 [1,7 por cento]), distúrbios do desenvolvimento (25 [0,5 por cento]), doenças imunomediadas (10 [0,2 por cento]) e doenças nutricionais (6 [0,1 por cento]). Outros distúrbios, que incluem doenças multifatoriais ou idiopáticas, contribuíram com 80 (1,6 por cento) casos. Dos 4.844 casos, em 1.548 (32,0 por cento) não foi possível estabelecer a causa da morte ou a razão para a eutanásia. Doenças infecciosas e parasitárias (principalmente cinomose, parvovirose e verminose intestinal), neoplasmas (principalmente neoplasmas mamários e linfoma), distúrbios causados por agentes físicos (principalmente atropelamento por veículos automotivos) e doenças degenerativas (principalmente insuficiência renal crônica, cirrose e insuficiência cardíaca congestiva) foram as principais categorias de doenças relacionadas com morte ou eutanásia de cães dessa mesorregião. Entretanto, quando os cães são avaliados de acordo com suas idades, tais categorias possuem prevalências...

The main objective of this study was to investigate the prevalence of diseases culminating with death or motivating euthanasia of dogs from the midland region of the Midwest of Rio Grande do Sul State, Brazil. The necropsy files of the Laboratório de Patologia Veterinária (LPV) of the Universidade Federal de Santa Maria (UFSM) were accessed and necropsy protocols of dogs necropsied between January 1965 and December 2004 were reviewed. During this period 4,844 reports of canine necropsies were filed at the LPV-UFSM. The case distribution in relation to the disease categories diagnosed was as follows: infectious and parasitic diseases (1,693 [35.0 percent]); neoplasms (378 [7.8 percent]); disorders caused by physical agents (369 [7.6 percent]); degenerative diseases (342 [7.1 percent]); poisonings and toxinfections (112 [2.3 percent]); euthanasia due to convenience (101 [2.1 percent]); metabolic and endocrinological diseases (97 [2.0 percent]); iatrogenic disorders (83 [1.7 percent]); developmental disorders (25 [0.5 percent]); immune mediate diseases (10 [0.2 percent]); and nutritional disorders (6 [0.1 percent]). Other disorders, including multifactorial or idiopathic diseases contributed 80 (1.6 percent) cases. In 1,548 (32.0 percent) out of the 4,844 cases it was not possible to establish either cause of death or reason for euthanasia. Infectious and parasitic diseases (mainly canine distemper, parvoviral enteritis and intestinal parasitism), neoplasia (mainly mammary neoplasms and lymphoma), disorders caused by physical agents (mainly accidents caused by automotive vehicles) and degenerative diseases (mainly chronic renal failure, cirrhosis, and congestive heart failure) were the main disease categories causing death or motivating euthanasia in dogs of this midland region. However, when cases were evaluated in relation with the age of the dog, the disease prevalence differed. The main causes of death in puppies were infectious and...

Aspectos clinicopatológicos de 620 casos neurológicos de cinomose em cães / : Clinicopathological features in 620 neurological cases of canine distemper

Os protocolos de 5.361 necropsias de cães realizadas no Laboratório de Patologia Veterinária da Universidade Federal de Santa Maria de 1965 a 2006 foram revisados à procura de casos de cinomose. Seiscentos e oitenta e três casos (12,7 por cento) da doença foram encontrados, dos quais 620 apresentavam sinais neurológicos. Desses 620, os seguintes dados foram recuperados para cada caso: idade, sinais clínicos, achados histopatológicos e presença ou não de doença concomitante. Faixas etárias foram classificadas como filhotes (até 1 ano), adultos (de 1 a 9 anos) e idosos (10 anos de idade ou mais). Lesões histológicas foram observadas em 565 (91,1 por cento) dos 620 casos com sinais neurológicos de cinomose e em 554 desses casos a idade foi registrada no protocolo com a seguinte distribuição por faixa etária: 45,9 por cento de filhotes, 51,4 por cento de adultos e 2,7 por cento de idosos. Os sinais neurológicos compreendiam um largo espectro de distúrbios motores, posturais e do comportamento, que podiam ocorrer juntos ou individualmente. Os sinais clínicos mais freqüentes foram mioclonia (38,4 por cento), incooordenação motora (25,0 por cento), convulsões (18,5 por cento) e paraplegia (13,4 por cento). Em 98,4 por cento dos 565 cães com alterações histopatológicas no encéfalo, foram observadas desmielinização, encefalite não-supurativa ou uma combinação dessas duas lesões. Corpúsculos de inclusão foram observados em diferentes células de 343 dos 565 cães com alterações histopatológicas no encéfalo. Em 170 (49,6 por cento) o tipo celular com inclusão não foi mencionado no protocolo; nos restantes, as inclusões foram vistas em astrócitos (94,8 por cento dos casos), neurônios (3,5 por cento), oligodendrócitos (1,1 por cento) e células do epêndima (0,6 por cento). Levando em consideração o tipo de lesões e as faixas etárias, casos com desmielinização e encefalite não-supurativa ocorreram em 40,0 por cento dos filhotes, 51,2 por cento dos adultos...

The files of 5,361 necropsies performed in dogs in the Veterinary Pathology Laboratory of the Federal University of Santa Maria during 1965-2006 were reviewed in search of cases of canine distemper. Six hundred and eighty three cases (12.7 percent) of the disease were found, 620 of which had neurological signs. From those 620, the following data on each case were retrieved: age, clinical signs, histopathology and concomitance or not of another disease. Age groups were classified as puppies (up to 1 year of age), adults (from 1 to 9 years) and aged (from 10 years on). In 565 out of the 620 (91.1 percent) neurological cases of canine distemper, histopathological brain changes were observed and in 554 of those 565 the age was registered in the files with following age group distribution: 45.9 percent of puppies, 51.4 percent of adults, and 2.7 percent of aged dogs. Neurological clinical signs encompassed a large spectrum of motor, postural and behavioral disturbances which could occur together or individually. Most frequent clinical signs were myoclonus (38.4 percent), motor incoordination (25.0 percent), seizures (18.5 percent), and paraplegia (13.4 percent). In 98.4 percent of the 565 dogs with histopathological changes in the brain demyelination, non-suppurative encephalitis or a combination of these two were found. Intranuclear eosinophilic inclusion bodies were observed in different brain cells of 343 of the 565 dogs with histopathological changes. In 170 (49.6 percent) the cellular type bearing the inclusions was not mentioned in the file and in the remaining cases the inclusions were seen in astrocytes (94.8 percent of the cases), neurons (3.5 percent), oligodendrocytes (1.1 percent), and ependyma cells (0.6 percent). Taking in consideration the type of lesions and the age groups, cases with combined demyelination and non-suppurative encephalitis occurred in 40.0 percent of the puppies, 51.2 percent of the adult dogs and 72.7 percent...

Aspectos clinicopatológicos de 620 casos neurológicos de cinomose em cães: Clinicopathological features in 620 neurological cases of canine distemper / x

Os protocolos de 5.361 necropsias de cães realizadas no Laboratório de Patologia Veterinária da Universidade Federal de Santa Maria de 1965 a 2006 foram revisados à procura de casos de cinomose. Seiscentos e oitenta e três casos (12,7 por cento) da doença foram encontrados, dos quais 620 apresentavam sinais neurológicos. Desses 620, os seguintes dados foram recuperados para cada caso: idade, sinais clínicos, achados histopatológicos e presença ou não de doença concomitante. Faixas etárias foram classificadas como filhotes (até 1 ano), adultos (de 1 a 9 anos) e idosos (10 anos de idade ou mais). Lesões histológicas foram observadas em 565 (91,1 por cento) dos 620 casos com sinais neurológicos de cinomose e em 554 desses casos a idade foi registrada no protocolo com a seguinte distribuição por faixa etária: 45,9 por cento de filhotes, 51,4 por cento de adultos e 2,7 por cento de idosos. Os sinais neurológicos compreendiam um largo espectro de distúrbios motores, posturais e do comportamento, que podiam ocorrer juntos ou individualmente. Os sinais clínicos mais freqüentes foram mioclonia (38,4 por cento), incooordenação motora (25,0 por cento), convulsões (18,5 por cento) e paraplegia (13,4 por cento). Em 98,4 por cento dos 565 cães com alterações histopatológicas no encéfalo, foram observadas desmielinização, encefalite não-supurativa ou uma combinação dessas duas lesões. Corpúsculos de inclusão foram observados em diferentes células de 343 dos 565 cães com alterações histopatológicas no encéfalo. Em 170 (49,6 por cento) o tipo celular com inclusão não foi mencionado no protocolo; nos restantes, as inclusões foram vistas em astrócitos (94,8 por cento dos casos), neurônios (3,5 por cento), oligodendrócitos (1,1 por cento) e células do epêndima (0,6 por cento). Levando em consideração o tipo de lesões e as faixas etárias, casos com desmielinização e encefalite não-supurativa ocorreram em 40,0 por cento dos filhotes, 51,2 por cento dos adultos...

The files of 5,361 necropsies performed in dogs in the Veterinary Pathology Laboratory of the Federal University of Santa Maria during 1965-2006 were reviewed in search of cases of canine distemper. Six hundred and eighty three cases (12.7 percent) of the disease were found, 620 of which had neurological signs. From those 620, the following data on each case were retrieved: age, clinical signs, histopathology and concomitance or not of another disease. Age groups were classified as puppies (up to 1 year of age), adults (from 1 to 9 years) and aged (from 10 years on). In 565 out of the 620 (91.1 percent) neurological cases of canine distemper, histopathological brain changes were observed and in 554 of those 565 the age was registered in the files with following age group distribution: 45.9 percent of puppies, 51.4 percent of adults, and 2.7 percent of aged dogs. Neurological clinical signs encompassed a large spectrum of motor, postural and behavioral disturbances which could occur together or individually. Most frequent clinical signs were myoclonus (38.4 percent), motor incoordination (25.0 percent), seizures (18.5 percent), and paraplegia (13.4 percent). In 98.4 percent of the 565 dogs with histopathological changes in the brain demyelination, non-suppurative encephalitis or a combination of these two were found. Intranuclear eosinophilic inclusion bodies were observed in different brain cells of 343 of the 565 dogs with histopathological changes. In 170 (49.6 percent) the cellular type bearing the inclusions was not mentioned in the file and in the remaining cases the inclusions were seen in astrocytes (94.8 percent of the cases), neurons (3.5 percent), oligodendrocytes (1.1 percent), and ependyma cells (0.6 percent). Taking in consideration the type of lesions and the age groups, cases with combined demyelination and non-suppurative encephalitis occurred in 40.0 percent of the puppies, 51.2 percent of the adult dogs and 72.7 percent...