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1.
Artigo em Inglês | MEDLINE | ID: mdl-37442311

RESUMO

Atmospheric particulate matter (APM) produced by the steel industry comprises a complex mixture of particles that includes a wide variety of metals and metallic nanoparticles. These particles settle out onto areas surrounding the industries. There is evidence that this 'settleable' APM (SePM) may cause air-to-water cross-contamination with significant effects on aquatic biota. Recent investigations have reported sublethal impacts on the gill structure and blood oxygen-carrying capacity of fishes, which raises the hypothesis that there will be consequences for gas exchange capacity and ability to support aerobic activities. Therefore, we investigated the effects of an environmentally relevant level of SePM contamination on swimming performance and associated aerobic metabolic rates in Nile tilapia, Oreochromis niloticus. Short-term exposure (96 h) to SePM reduced critical swimming speed, energetic efficiency of aerobic swimming, standard metabolic rate, maximum metabolic rate, and aerobic scope. The compromised swimming performance could have adverse ecological effects by limiting foraging ability, predator evasion, territorial protection, and migration. The impairments to aerobic capacity could also affect overall fish performance by influencing long-term energy balance and allocation to growth and reproduction. Thus, despite being sublethal, SePM contamination is considerably debilitating, and if its limiting effects are not compensated for in the longer term, this may reduce the survival and fitness of fish populations.


Assuntos
Ciclídeos , Animais , Natação , Material Particulado/toxicidade , Metabolismo Energético , Consumo de Oxigênio
2.
Angiogenesis ; 26(3): 365-384, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36631598

RESUMO

The Feline Leukemia Virus Subgroup C Receptor 1a (FLVCR1a) is a transmembrane heme exporter essential for embryonic vascular development. However, the exact role of FLVCR1a during blood vessel development remains largely undefined. Here, we show that FLVCR1a is highly expressed in angiogenic endothelial cells (ECs) compared to quiescent ECs. Consistently, ECs lacking FLVCR1a give rise to structurally and functionally abnormal vascular networks in multiple models of developmental and pathologic angiogenesis. Firstly, zebrafish embryos without FLVCR1a displayed defective intersegmental vessels formation. Furthermore, endothelial-specific Flvcr1a targeting in mice led to a reduced radial expansion of the retinal vasculature associated to decreased EC proliferation. Moreover, Flvcr1a null retinas showed defective vascular organization and loose attachment of pericytes. Finally, adult neo-angiogenesis is severely affected in murine models of tumor angiogenesis. Tumor blood vessels lacking Flvcr1a were disorganized and dysfunctional. Collectively, our results demonstrate the critical role of FLVCR1a as a regulator of developmental and pathological angiogenesis identifying FLVCR1a as a potential therapeutic target in human diseases characterized by aberrant neovascularization.


Assuntos
Células Endoteliais , Neoplasias , Adulto , Animais , Humanos , Camundongos , Células Endoteliais/fisiologia , Neovascularização Patológica/genética , Neovascularização Fisiológica/genética , Peixe-Zebra
3.
Lett Appl Microbiol ; 75(5): 1383-1388, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35971818

RESUMO

The objective of this study is to verify in vitro susceptibility of Pythium insidiosum against the agricultural fungicides mefenoxam and pyraclostrobin and evaluate the toxicity of both compounds. Twenty-one P. insidiosum isolates were tested against mefenoxam and pyraclostrobin using the broth microdilution method. Minimum inhibitory and oomicidal concentrations for both compounds were established. Additionally, scanning electron microscopy was performed on P. insidiosum hyphae treated with the sublethal concentration of each fungicide. The toxicity of the compounds was evaluated in vivo Caenorhabditis elegans model. The concentration to inhibit 100% of P. insidiosum growth ranged from 0·625 to 10 µg ml-1 for mefenoxam and from 0·019 to 5 µg ml-1 for pyraclostrobin. The SEM analysis revealed changes on the surface of the hyphae treated with the fungicides, suggesting possible damage caused by these compounds. There was no evidence of toxicity in vivo models. Mefenoxam and pyraclostrobin did not show toxicity at the doses evaluated and have inhibitory effects on the pathogenic oomycete P. insidiosum. However, further evaluations of their pharmacokinetics and toxicity in different animal species and possible pharmacological interactions are necessary to infer a possible use in the clinical management of pythiosis.


Assuntos
Fungicidas Industriais , Pythium , Animais , Fungicidas Industriais/farmacologia , Testes de Sensibilidade Microbiana
4.
Artigo em Inglês | MEDLINE | ID: mdl-35452846

RESUMO

Atmospheric particulate matter (APM) emitted by iron ore processing industries has a complex composition, including diverse metallic particles and nanoparticles. Settleable APM (SePM) causes air to water cross-contamination and has recently been demonstrated to have harmful sublethal impacts on fish, eliciting stress responses, affecting the immune system, and reducing blood oxygen-carrying capacity. These findings imply potential consequences for fish aerobic performance and energy allocation, particularly in their ability to tolerate respiratory challenges such as aquatic hypoxia. To assess that potential limitation, we analyzed metabolic, cardiorespiratory, and morphological alterations after exposing tilapia, Oreochromis niloticus, to an environmentally relevant concentration of SePM (96 h) and progressive hypoxia. The contamination initiated detectable gill damage, reducing respiratory efficiency, increasing ventilatory effort, and compromising fish capacity to deal with hypoxia. Even in normoxia, the resting respiratory frequency was elevated and limited respiratory adjustments during hypoxia. SePM increased O2crit from 26 to 34% of O2 (1.84 to 2.76 mg O2·L-1). Such ventilatory inefficacy implies higher ventilatory cost with relevant alterations in energy allocation. Progression in gill damage might be problematic and cause: infection, blood loss, ion imbalance, and limited cardiorespiratory performance. The contamination did not cause immediate lethality but may threaten fish populations due to limitations in physiological performance. This was the first investigation to evaluate the physiological responses of fish to hypoxia after SePM contamination. We suggest that the present level of environmental SePM deserves attention. The present results demonstrate the need for comprehensive studies on SePM effects in aquatic fauna.


Assuntos
Ciclídeos , Animais , Ciclídeos/metabolismo , Brânquias/metabolismo , Hipóxia , Oxigênio/metabolismo , Material Particulado/metabolismo , Material Particulado/toxicidade
5.
Colloids Surf B Biointerfaces ; 181: 856-863, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31382333

RESUMO

Flavonoid-metal complexes are widely studied because of their interesting luminescent behavior and biological activity. Despite the extensive exploration of flavonoid-metal coordination processes in solution, the formation of complexes using the flavonoid molecule inserted in a lipid membrane has been little investigated. This effect could provide important insight into the biological activity of flavonoids at lipid membranes and could represent an attractive strategy to design supramolecular structures. Here, we studied the complexation between Sr2+ and morin inserted in an octadecylphosphonic acid (OPA) Langmuir monolayer. This is a relevant system due to the synergism imposed by the association of the Sr2+ ability to control bone formation/resorption with the morin antioxidative effect. Morin incorporation into the OPA monolayers and further Sr2+ complexation were monitored by surface pressure isotherms. Electronic absorption spectroscopy and fluorescence techniques showed Sr-morin complexation both in solution and at the air-liquid interface. Although morin complexation has been described to occur only at basic pH, the specific thermodynamic properties at the air-liquid interface drove metal complexation. LB films were deposited on Ti surfaces, and the resulting OPA/Sr-morin coatings exhibited high surface free energy and increase on its polar component. This optimized surface feature supported further serum protein adsorption and osteoblast growth and differentiation, indicating that these lipid-based coatings are promising for bioactive coating design. This study paves the way for the use of this lipid-based coating in the design of implants for faster osteointegration. Moreover, flavonoid-metal complexation at membranes could also help to shed light on the biological role played by flavonoids.


Assuntos
Complexos de Coordenação/farmacologia , Desenho de Fármacos , Flavonoides/farmacologia , Estrôncio/farmacologia , Adsorção , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Flavonoides/química , Humanos , Estrutura Molecular , Imagem Óptica , Osteoblastos/efeitos dos fármacos , Tamanho da Partícula , Estrôncio/química , Propriedades de Superfície , Termodinâmica , Molhabilidade
7.
Toxicon ; 71: 113-20, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23726858

RESUMO

The effects and susceptibility of donkeys to Crotalaria juncea and Crotalaria retusa poisoning were determined at high and low doses. Seeds of C. juncea containing 0.074% of dehydropyrrolizidine alkaloids (DHPAs) (isohemijunceines 0.05%, trichodesmine 0.016%, and junceine 0.008%) were administered to three donkeys at 0.3, 0.6 and 1 g/kg body weight (g/kg) daily for 365 days. No clinical signs were observed and, on liver and lung biopsies, the only lesion was a mild liver megalocytosis in the donkeys ingesting 0.6 and 1 g/kg/day. Two other donkeys that received daily doses of 3 and 5 g seed/kg showed initial respiratory signs 70 and 40 days after the start of the administration, respectively. The donkeys were euthanized following severe respiratory signs and the main lung lesions were proliferation of Clara cells and interstitial fibrosis. Three donkeys ingested seeds of C. retusa containing 5.99% of monocrotaline at daily doses of 0.025, 0.05 and 0.1 g/kg for 365 days. No clinical signs were observed and, on liver and lung biopsies, the only lesion was moderate liver megalocytosis in each of the three donkeys. One donkey that received a single dose of 5 g/kg of C. retusa seeds and another that received 1 g/kg daily for 7 days both showed severe clinical signs and died with diffuse centrilobular liver necrosis. No lung lesions were observed. Another donkey that received a single dose of 2.5 g/kg of C. retusa seeds showed no clinical signs. The hepatic and pneumotoxic effects observed are consistent with an etiology involving DHPAs. Furthermore, the occurrence of lung or liver lesions correlates with the type of DHPAs contained in the seeds. Similarly as has been reported for horses, the data herein suggest that in donkeys some DHPAs are metabolized in the liver causing liver disease, whereas others are metabolized in the lung by Clara cells causing lung disease.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/patologia , Crotalaria/química , Crotalaria/intoxicação , Pneumopatias/patologia , Alcaloides de Pirrolizidina/intoxicação , Animais , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Crotalaria/classificação , Equidae , Fibrose/induzido quimicamente , Fígado/efeitos dos fármacos , Fígado/patologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pneumopatias/induzido quimicamente , Monocrotalina/análogos & derivados , Monocrotalina/intoxicação , Intoxicação por Plantas/patologia , Intoxicação por Plantas/veterinária , Sementes/química , Sementes/intoxicação
8.
Res Vet Sci ; 95(1): 200-3, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23587159

RESUMO

Tephrosia cinerea has been associated with ascites and liver fibrosis in sheep in Brazil. The dried plant was fed ad libitum to three sheep for 55-80 days. Three additional sheep were used as controls. All the treated sheep presented with hypoalbuminemia and increased γ-glutamyltransferase and aspartate aminotransferase activities. Anorexia, apathy, rough coat, ascites, and emaciation were observed after 45-60 days of feeding with T. cinerea. At necropsy 55-80 days after feeding of the plant commenced, the treated sheep had ascites, hydrothorax and hydropericardium, and their livers were firm and whitish, with a nodular surface. Histologically, the main hepatic lesions were periacinar fibrosis associated with hemorrhages and necrosis. On electron microscopy, a severe swelling of sinusoidal endothelial cells, frequently obstructing the lumen of the sinusoid was observed. The space of Disse was compressed by the swollen endothelial cells and microvilli usually present on the surface of hepatocytes adjacent to the space of Disse were not apparent. Dense bundles of collagen fibers were present in the spaces of Disse and within the sinusoids between profiles of swollen endothelial cells. It is concluded that T. cinerea causes periacinar fibrosis, similar to poisoning by Galenia africana in sheep and goats and veno-occlusive disease in different species.


Assuntos
Cirrose Hepática/veterinária , Doenças dos Ovinos/patologia , Tephrosia , Animais , Aspartato Aminotransferases/sangue , Brasil , Histocitoquímica/veterinária , Cirrose Hepática/enzimologia , Cirrose Hepática/patologia , Masculino , Microscopia Eletrônica de Transmissão/veterinária , Albumina Sérica/metabolismo , Ovinos , Doenças dos Ovinos/enzimologia , Doenças dos Ovinos/etiologia , gama-Glutamiltransferase/sangue
9.
Vet Pathol ; 50(5): 775-8, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23417165

RESUMO

Trema micrantha, a fast-growing tree distributed throughout the Americas, produces palatable leaves that have been associated with hepatic necrosis and acute death when consumed by livestock. This report describes fatal pulmonary disease of sheep triggered by consumption of Trema micrantha. Affected sheep had severe progressive dyspnea for a few days before death. Subcutaneous and mediastinal emphysema, reddened lungs, interalveolar septal thickening, and diffuse type II pneumocyte proliferation were the main pathological findings. After ingesting 77.5 and 102.5 g/kg (divided in 3 doses, at 30-day intervals) of T. micrantha leaves, 2 additional sheep developed the same condition. These findings indicate that T. micrantha toxicosis should be considered in the differential diagnosis of ovine respiratory disease.


Assuntos
Dispneia/veterinária , Enfisema Mediastínico/veterinária , Intoxicação/veterinária , Doenças dos Ovinos/induzido quimicamente , Doenças dos Ovinos/diagnóstico , Doenças dos Ovinos/patologia , Trema/toxicidade , Animais , Brasil , Diagnóstico Diferencial , Dispneia/induzido quimicamente , Dispneia/patologia , Evolução Fatal , Pulmão/patologia , Enfisema Mediastínico/induzido quimicamente , Enfisema Mediastínico/patologia , Plantas Tóxicas/efeitos adversos , Intoxicação/diagnóstico , Intoxicação/patologia , Ovinos
10.
J Comp Pathol ; 148(4): 354-60, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23123123

RESUMO

Clinical, histopathological and ultrastructural findings of caprine dystrophic epidermolysis bullosa (DEB) with autosomal recessive inheritance are reported. The goats presented with exungulation, erosions, crusts and scars on the skin and ulcers in the oral cavity. Microscopically, the skin showed subepidermal separation with clefts filled occasionally with clear eosinophilic fluid, cellular debris or neutrophils. Ultrastructurally, the site of blister formation was the sublamina densa in the epidermal basement membrane zone. In skin with blister formation and in clinically uninvolved skin, the basal lamina was preserved, but the anchoring fibrils were sparse and rudimentary. A twin brother of an affected kid was mated over 5 years with his mother; three out of the 10 kids born presented with epidermolysis bullosa, indicating that the disease has an autosomal recessive mode of inheritance. It is suggested that the disease is similar to human severe generalized recessive DEB.


Assuntos
Cicatriz/veterinária , Epidermólise Bolhosa Distrófica/veterinária , Doenças das Cabras/patologia , Úlceras Orais/veterinária , Pele/patologia , Animais , Cicatriz/genética , Cicatriz/patologia , Epiderme/patologia , Epiderme/ultraestrutura , Epidermólise Bolhosa Distrófica/genética , Epidermólise Bolhosa Distrófica/patologia , Feminino , Doenças das Cabras/genética , Cabras , Masculino , Úlceras Orais/genética , Úlceras Orais/patologia , Linhagem , Pele/ultraestrutura
11.
Genet Mol Res ; 10(3): 1942-7, 2011 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-21948756

RESUMO

Artificial insemination has been used to improve production in Brazilian dairy cattle; however, this can lead to problems due to increased inbreeding. To evaluate the effect of the magnitude of inbreeding coefficients on predicted transmitting abilities (PTAs) for milk traits of Holstein and Jersey breeds, data on 392 Holstein and 92 Jersey sires used in Brazil were tabulated. The second-degree polynomial equations and points of maximum or minimal response were estimated to establish the regression equation of the variables as a function of the inbreeding coefficients. The mean inbreeding coefficient of the Holstein bulls was 5.10%; this did not significantly affect the PTA for percent milk fat, protein percentage and protein (P = 0.479, 0.058 and 0.087, respectively). However, the PTAs for milk yield and fat decreased significantly after reaching inbreeding coefficients of 6.43 (P = 0.034) and 5.75 (P = 0.007), respectively. The mean inbreeding coefficient of Jersey bulls was 6.45%; the PTAs for milk yield, fat and protein, in pounds, decreased significantly after reaching inbreeding coefficients of 15.04, 9.83 and 12.82% (P < 0.001, P = 0.002, and P = 0.001, respectively). The linear regression was only significant for fat and protein percentages in the Jersey breed (P = 0.002 and P = 0.005, respectively). The PTAs of Holstein sires were more affected by smaller magnitudes of inbreeding coefficients than those of Jersey sires. It is necessary to monitor the inbreeding coefficients of sires used for artificial insemination in breeding schemes in Brazil, since the low genetic variability of the available sires may lead to reduced production.


Assuntos
Cruzamento/métodos , Bovinos/genética , Endogamia , Leite/fisiologia , Animais , Brasil , Bovinos/fisiologia , Laticínios , Indústria de Laticínios , Feminino , Variação Genética , Inseminação Artificial/veterinária , Lactação/genética , Fenótipo , Sêmen
12.
Pesqui. vet. bras ; 31(4): 326-330, abr. 2011. ilus
Artigo em Português | LILACS | ID: lil-584047

RESUMO

Descrevem-se dois surtos de intoxicação por Senecio spp. em ovinos a campo no sul do Rio Grande do Sul. A enfermidade ocorreu no ano 2006 em duas propriedades que estavam severamente invadidas pela planta e com acentuada escassez de forragem. A morbidade nos dois surtos variou de 10 por cento a 9,5 por cento nas duas propriedades, respectivamente. Na primeira propriedade os animais eram nascidos e criados na área e na outra os ovinos haviam sido adquiridos alguns meses antes do surto. Os sinais clínicos caracterizaram-se por emagrecimento progressivo, apatia, fraqueza, icterícia e fotossensibilização. Macroscopicamente, o fígado dos ovinos necropsiados estava aumentado de tamanho, amarelado, com superfície capsular irregular e vesícula biliar aumentada de tamanho e com edema da parede. Ao corte no fígado havia nódulos bem delimitados, esbranquiçados com 1-3mm de diâmetro. Havia, ainda, ascite e discreto edema de mesentério. Microscopicamente, as lesões hepáticas eram semelhantes em todos os fígados e caracterizadas por megalocitose, fibrose periportal, presença de hepatócitos tumefeitos, vacuolizados e de hepatócitos necróticos distribuídos aleatoriamente pelo parênquima hepático, hiperplasia das células dos ductos biliares e presença de pseudo-inclusões nos núcleos de hepatócitos. Encefalopatia hepática (status spongiosus) foi observada em todos os ovinos necropsiados. O diagnóstico foi baseado na epidemiologia, sinais clínicos, lesões macroscópicas e histológicas observadas. Concluiu-se que, apesar de a intoxicação por Senecio spp. ser pouco frequente em ovinos e essa espécie animal controlar eficientemente a planta, isso, aparentemente, depende da lotação utilizada e surtos da intoxicação podem ocorrer quando esta lotação é menor que 0,2 ovinos por hectare e há carência de forragem acentuada.


Two outbreaks of Senecio spp. poisoning in grazing sheep in southern Rio Grande do Sul are described. The disease occurred in 2006 on two farms that were heavily infested with Senecio spp. and had shortage of forage. The morbidity in both outbreaks was 10 percent and 9.5 percent, respectively. In one case the sheep were born and had grown up on the farm. On the other, the sheep flock was introduced into the farm some months before the outbreak. Clinical signs included progressive emaciation, apathy, weakness, jaundice and photodermatitis. At necropsy, the sheep had an augmented yellowish and firm liver with irregular capsular surface, and an extended and edematous gallbladder. There was distension and edema of the gallbladder. The cut surface the liver showed well-circumscribed whitish nodules measuring 1-3mm in diameter, which were randomly scattered throughout the hepatic parenchyma. There was also edema of mesentery and ascitis. Histopathological findings of the liver included hepatomegalocytosis, bile duct hyperplasia and periportal fibrosis. There were also swollen hepatocytes, randomly scattered necrotic hepatocytes and nuclear pseudo inclusions. Hepatic encephalopathy (status spongiosus) was observed in the brain in all necropsied sheep. The diagnosis of Senecio poisoning was based on epidemiological data, clinical signs, necropsy findings and histological lesions. It was concluded that despite infrequent, Senecio spp. poisoning in sheep may occur when animals are placed in areas heavily invaded by the plants. Although sheep can efficiently control Senecio spp. in paddocks, this apparently depends on the stocking rate, and outbreaks may occur when stocking rate is less than 0.2 sheep per hectare and when there is severe shortage of forage.


Assuntos
Animais , Plantas Tóxicas/intoxicação , Senécio/intoxicação , Senécio/toxicidade
13.
Pesqui. vet. bras ; 31(4): 331-335, abr. 2011. ilus, graf, tab
Artigo em Português | LILACS | ID: lil-584048

RESUMO

Foi realizado um estudo retrospectivo de casos de raiva paralítica em bovinos na área de influência do Laboratório Regional de Diagnóstico (LRD) da Faculdade de Veterinária, Universidade Federal de Pelotas (UFPel), ocorridos em 1978-2007. Foram estudados também 11 surtos de raiva observados em 2008-2010, na mesma região. Neste período morreram 42 animais de um total de 686 sob risco. A idade dos animais foi de 1-6 anos e o curso clínico de 4-14 dias. No estudo retrospectivo de 1978-2007 foram identificados 77 surtos ou casos isolados de raiva paralítica em bovinos. A morbidade em todos os surtos diagnosticados em 1978-2010 variou de 0,37 por cento a 20 por cento. Vinte e quatro casos ocorreram no outono, sete na primavera, 14 no verão e 16 no inverno. O diagnóstico foi realizado pela epidemiologia, sinais clínicos e lesões histológicas observadas. No estudo dos casos de raiva paralítica em bovinos ocorridos a partir de 2008, o diagnóstico foi confirmado pela técnica de imuno-histoquímica utilizando anticorpo policlonal anti-virus rábico. Em dois destes casos não foi observada meningoencefalite não-supurativa, porém a imuno-histoquímica demonstrou a presença do antígeno viral. Esta técnica é uma importante ferramenta para o diagnóstico de raiva, devendo ser utilizada em todos os casos suspeitos nos quais não se evidenciam lesões de encefalite.


A retrospective study of paralytic rabies in cattle in southern Rio Grande do Sul, Brazil, diagnosed from 1978 to 2007 by the Regional Diagnostic Laboratory (LRD) of the Veterinary School, Federal University of Pelotas (UFPel), with 77 outbreaks or isolated cases of paralytic rabies in cattle, is reported. A study of 11 outbreaks of rabies, observed from 2008 to 2010 in the same region, where 42 cattle aged 1-6 years died from a total of 686 at risk, with a clinical course of 4 to 14 days, was also made. The morbidity of all outbreaks diagnosed from 1978-2010 ranged from 0.37 percent to 20 percent; 24 cases occurred in autumn, 7 in spring, 14 in summer, and 16 in winter. The diagnosis was achieved by epidemiology, clinical signs and histological lesions. Immunohistochemistry using rabies virus polyclonal antibody was positive in all cases. In two cases non-suppurative meningoencephalitis was not observed, and the diagnosis was confirmed by immunohistochemistry. This technique is an important tool for the diagnosis of rabies and should be used in all suspected cases in which no evidence of encephalitis is observed.


Assuntos
Animais , Imuno-Histoquímica , Vírus da Raiva/patogenicidade
14.
Pesqui. vet. bras ; 31(4): 291-296, abr. 2011. ilus
Artigo em Português | LILACS | ID: lil-584054

RESUMO

Descrevem-se casos de morte súbita em bovinos associados com a ingestão de Amorimia (Mascagnia) exotropica em seis propriedades rurais localizadas na região metropolitana de Porto Alegre e na serra gaúcha. Os bovinos intoxicados foram encontrados mortos sem história de sinais clínicos prévios, ou apresentaram tremores musculares, quedas bruscas, movimentos de pedalagem, opistótono, respiração ofegante e decúbito lateral, quando induzidos ao movimento poucos minutos antes da morte. Registrou-se maior número de casos entre os meses de maio e agosto. Nove bovinos foram necropsiados e os principais achados macroscópicos observados foram mucosa oral levemente cianótica (3/9), hidropericárdio leve a moderado (3/9), petéquias e equimoses no epicárdio (5/9), coágulo no interior do ventrículo esquerdo (4/9), edema pulmonar (5/9) e mucosas vermelhas no abomaso e no intestino delgado (6/9). Histologicamente havia necrose de coagulação no miocárdio (9/9) caracterizada por retração celular, aumento da eosinofilia do citoplasma com perda das estriações, vacúolos intracitoplasmáticos, núcleos em picnose, vacúolos intranucleares com marginalização da cromatina e ocasionais núcleos em cariorrexia e cariólise. No coração, edema intersticial (3/9) e infiltrado inflamatório intersticial predominantemente mononuclear (7/9) também foram observados. Nos rins de três bovinos havia degeneração hidrópico-vacuolar multifocal das células epiteliais dos túbulos contorcidos distais associada com núcleos picnóticos deslocados para periferia da célula.


Cases of sudden death in cattle were associated with the consumption of Amorimia (Mascagnia) exotropica and occurred in six ranches located in the mountainous region of Rio Grande do Sul and the metropolitan region of Porto Alegre, Brazil. Affected cattle were found dead with no history of previous clinical signs, or showed muscular tremors, falls, paddling, opistotonus, panting, and lateral recumbence after being induced to move, few minutes before death. Most cases were recorded between May and August. Nine cattle were necropsied and main gross findings were oral mucosae slightly cyanotic (3/9), mild to intermediate hydropericardium (3/9), epicardial petechiae and ecchymoses (5/9), clot within the left ventricle (4/9), lung edema (5/9), apart of abomasal and small intestinal reddened mucosa (6/9). Histologically, there was myocardial coagulation necrosis (9/9), which was characterized by cellular retraction, enhanced cytoplasmic eosinophilia, lack of cytoplasmic striations, intracytoplasmic vacuoles, nuclear piknosis, intranuclear vacuoles, chromatin marginalization and occasional nuclear karyorrhexis and karyolysis. There also were interstitial edema (3/9) and interstitial inflammatory infiltrate (mainly mononuclear) (7/9) in the heart, apart of multifocal vacuolar-hydropic degeneration in the epithelial cells of the distal convoluted tubules associated with pyknotic and eccentric nuclei in the kidneys of three cattle.


Assuntos
Animais , Malpighiaceae/intoxicação , Malpighiaceae/toxicidade , Plantas Tóxicas/efeitos adversos
15.
Vet Pathol ; 46(5): 960-5, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19429990

RESUMO

Tetrapterys spp. have been reported as a cause of cardiac fibrosis, status spongiosus of the nervous system, and abortion. To study the intoxication by Tetrapterys multiglandulosa, 24 sheep were divided into 4 experimental groups of 4 sheep each and 1 control group. Groups 1 to 3, respectively, received 1, 1.5, and 3 g/kg body weight of the dry plant daily, starting on the 90th day of pregnancy. Group 4 received 1.5 g/kg from the 120th day of pregnancy to the end of gestation. All sheep from groups 2 and 3, except 1 that was submitted to cesarean delivery, aborted between 110 and 134 days of pregnancy. Seven fetuses had anasarca. Seven lambs from groups 1 and 4 were weak and died or were euthanatized. The other 2 were born weak with mild nervous signs but recovered. Cardiac fibrosis and status spongiosus of the nervous system were observed in newborn lambs and fetuses.


Assuntos
Aborto Animal/induzido quimicamente , Malpighiaceae/metabolismo , Doenças dos Ovinos/metabolismo , Animais , Animais Recém-Nascidos , Feminino , Malpighiaceae/toxicidade , Gravidez , Distribuição Aleatória , Ovinos
16.
Clin Transplant ; 22(5): 609-16, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18459998

RESUMO

Heme oxygenase-1 (HO-1) has a microsatellite polymorphism based on the number of guanosine-thymidine nucleotide repeats (GT) repeats that regulates expression levels and could have an impact on organ survival post-injury. We correlated HO-1 polymorphism with renal graft function. The HO-1 gene was sequenced (N = 181), and the allelic repeats were divided into subclasses: short repeats (S) (<27 repeats) and long repeats (L) (>/=27 repeats). A total of 47.5% of the donors carried the S allele. The allograft function was statistically improved six months, two and three yr after transplantation in patients receiving kidneys from donors with an S allele. For the recipients carrying the S allele (50.3%), the allograft function was also better throughout the follow-up, but reached statistical significance only three yr after transplantation (p = 0.04). Considering only those patients who had chronic allograft nephropathy (CAN; 74 of 181), allograft function was also better in donors and in recipients carrying the S allele, two and three yr after transplantation (p = 0.03). Recipients of kidney transplantation from donors carrying the S allele presented better function even in the presence of CAN.


Assuntos
Sobrevivência de Enxerto/genética , Heme Oxigenase-1/genética , Transplante de Rim , Doadores de Tecidos , Adulto , Estudos de Casos e Controles , Repetições de Dinucleotídeos/genética , Feminino , Frequência do Gene , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético/genética , Prognóstico , Regiões Promotoras Genéticas/genética , Adulto Jovem
17.
J Thromb Haemost ; 5(12): 2537-46, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17927807

RESUMO

BACKGROUND: Heme oxygenase-1 (HO-1), by exerting anti-inflammatory, antiproliferative, antiapoptotic and antioxidant effects in the vasculature, protects against atherosclerosis and post-transplant vasculopathy. We noted the overlap between the effects of HO-1 and those attributed to 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins). This led to an investigation of the role of HO-1 in statin-mediated cytoprotection in primary human endothelial cells (ECs), and the ability of Kruppel-like factor 2 (KLF2) to regulate HO-1 function. METHODS/RESULTS: Treatment of human umbilical vein and aortic ECs with atorvastatin significantly upregulated HO-1 promoter activity, mRNA expression and protein expression, increasing HO-1 enzymatic activity as shown by raised intracellular bilirubin IXalpha. This effect was indirect, dependent upon inhibition of HMG-CoA reductase and geranylgeranylation, and independent of nitric oxide or changes in mRNA stability. Atorvastatin protected ECs against the generation of reactive oxygen species and H(2)O(2)-induced injury. HO-1 inhibition, with small interfering RNA (siRNA) or zinc protoporphyrin IX, abrogated atorvastatin-mediated cytoprotection. Atorvastatin upregulated KLF2 expression, whereas KLF2 siRNA attenuated statin-induced HO-1 and its associated antioxidant cytoprotective effects. Iron chelation, adenoviral-mediated overexpression of ferritin or supplementation of culture media with biliverdin reversed the inhibitory effects of HO-1 and KLF2 siRNA, suggesting that bile pigments and ferritin mediate the antioxidant actions of statin-induced HO-1. CONCLUSIONS: We have identified a novel link between KLF2 and HO-1 in human vascular ECs, demonstrating that atorvastatin-mediated HO-1 upregulation, and its associated antioxidant effect, is KLF2-dependent. The relationship between KLF2 and HO-1 is likely to represent an important component of the vasculoprotective profile of statins.


Assuntos
Antioxidantes/farmacologia , Citoproteção , Células Endoteliais/efeitos dos fármacos , Heme Oxigenase-1/biossíntese , Ácidos Heptanoicos/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Fatores de Transcrição Kruppel-Like/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Pirróis/farmacologia , Atorvastatina , Bilirrubina/metabolismo , Biliverdina/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Células Endoteliais/enzimologia , Células Endoteliais/metabolismo , Indução Enzimática , Inibidores Enzimáticos/farmacologia , Ferritinas/genética , Ferritinas/metabolismo , Heme Oxigenase-1/antagonistas & inibidores , Heme Oxigenase-1/genética , Humanos , Peróxido de Hidrogênio/farmacologia , Quelantes de Ferro/farmacologia , Fatores de Transcrição Kruppel-Like/genética , Ácido Mevalônico/farmacologia , Oxidantes/farmacologia , Prenilação , Regiões Promotoras Genéticas/efeitos dos fármacos , Protoporfirinas/farmacologia , Interferência de RNA , RNA Mensageiro/biossíntese , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Terpenos/farmacologia
18.
Vet Pathol ; 43(4): 494-9, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16846991

RESUMO

A histopathologic, immunohistochemical, and ultrastructural study of the trachea and the bronchi of 6 rabbits experimentally intoxicated with the calcinogenic plant Solanum glaucophyllum was performed. Histologically, infiltration of the mucosa and the submucosa of the trachea and the bronchi by macrophages, multinucleated giant cells, a few lymphocytes and mast cells, and calcium deposits in the basal lamina of the epithelium and in elastic fibers were observed. Expression of osteocalcin, osteonectin, and osteopontin was detected in the mucosa, lamina propria, and epithelium. Electron microscopic study of the corresponding areas showed numerous macrophages in the process of fusion to form multinucleated giant cells, activated mesenchymal cells, and calcium precipitation in the basal lamina of epithelium and in elastic fibers. It is suggested that the high levels of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) in the plant induces macrophage proliferation, multinucleated giant-cell formation, mesenchymal cell activation, bone-protein synthesis, and calcification. In addition, the synthesis of 1,25(OH)2D3 by local macrophages may have contributed to the calcification.


Assuntos
Brônquios/patologia , Calcinose/veterinária , Células Gigantes/patologia , Macrófagos/patologia , Solanum glaucophyllum/intoxicação , Traqueia/patologia , Animais , Brônquios/metabolismo , Calcinose/metabolismo , Calcinose/patologia , Processos de Crescimento Celular/fisiologia , Células Gigantes/metabolismo , Imuno-Histoquímica/veterinária , Macrófagos/metabolismo , Masculino , Microscopia Eletrônica de Transmissão/veterinária , Osteocalcina/biossíntese , Osteonectina/biossíntese , Osteopontina , Coelhos , Sialoglicoproteínas/biossíntese , Traqueia/metabolismo
19.
J Parasitol ; 92(1): 93-9, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16629322

RESUMO

Molecular techniques were used to examine the phylogenetic relationships among Hepatozoon species isolated from 13 foxes and 15 opossums from Brazil, and from 15 dogs, 20 foxes, 45 rodents, and 330 domestic cats from Spain. Hemogregarine infection was confirmed by amplification of the 18S rRNA gene and later sequencing. No hemogregarine infections were found in opossums. The prevalence of Hepatozoon in canids ranged from 26.6% (symptomatic domestic dogs) to 90% (Spanish foxes). Four different H. canis genotypes were detected, as well as an H. americanum-related protozoan (97% identical to the USA strain). Two Spanish cats were parasitized by a Hepatozoon species (0.6% prevalence) that showed 96% sequence identity to H. canis. DNA amplification assays performed on Spanish rodents showed 2 bank voles (Clethrionomys glareolus) to be infected by a Hepatozoon species (4.44% prevalence) with 95% sequence identity to Hepatozoon sp. from cats. Phylogenetic analysis showed Hepatozoon to be a monophyletic genus, in which species from carnivorous mammals (Hepatozoon sp. from cats, H. americanum and H. canis) appear as a sister lineage of that of lower vertebrates and rodents. This association suggests that H. americanum evolved in ticks and carnivores (either canids, or felids, or both) rather than in other ectoparasites and other types of mammal.


Assuntos
Coccidiose/veterinária , Ectoparasitoses/veterinária , Eucoccidiida/classificação , Eucoccidiida/genética , Mamíferos/parasitologia , Doenças Transmitidas por Carrapatos/veterinária , Animais , Brasil/epidemiologia , Gatos , Coccidiose/epidemiologia , Coccidiose/parasitologia , Primers do DNA/química , DNA de Protozoário/química , Cães , Ectoparasitoses/epidemiologia , Raposas/parasitologia , Genótipo , Ixodidae/parasitologia , Dados de Sequência Molecular , Gambás/parasitologia , Filogenia , Prevalência , RNA Ribossômico 18S/genética , Roedores , Espanha/epidemiologia , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/parasitologia
20.
FASEB J ; 17(12): 1724-6, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12958189

RESUMO

Heme oxygenase-1 (HO-1) is induced under a variety of pro-oxidant conditions such as those associated with ischemia-reperfusion injury (IRI) of transplanted organs. HO-1 cleaves the heme porphyrin ring releasing Fe2+, which induces the expression of the Fe2+ sequestering protein ferritin. By limiting the ability of Fe2+ to participate in the generation of free radicals through the Fenton reaction, ferritin acts as an anti-oxidant. We have previously shown that HO-1 protects transplanted organs from IRI. We have linked this protective effect with the anti-apoptotic action of HO-1. Whether the iron-binding properties of ferritin contributed to the protective effect of HO-1 was not clear. We now report that recombinant adenovirus mediated overexpression of the ferritin heavy chain (H-ferritin) gene protects rat livers from IRI and prevents hepatocellular damage upon transplantation into syngeneic recipients. The protective effect of H-ferritin is associated with the inhibition of endothelial cell and hepatocyte apoptosis in vivo. H-ferritin protects cultured endothelial cells from apoptosis induced by a variety of stimuli. These findings unveil the anti-apoptotic function of H-ferritin and suggest that H-ferritin can be used in a therapeutic manner to prevent liver IRI and thus maximize the organ donor pool used for transplantation.


Assuntos
Apoptose , Ferritinas/genética , Hepatopatias/prevenção & controle , Traumatismo por Reperfusão/prevenção & controle , Adenoviridae/genética , Animais , Bovinos , Citoproteção , Endotélio/citologia , Ferritinas/fisiologia , Vetores Genéticos , Fígado/metabolismo , Hepatopatias/etiologia , Hepatopatias/metabolismo , Transplante de Fígado/efeitos adversos , Camundongos , Modelos Biológicos , Ratos , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/metabolismo
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