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1.
Vet Clin Pathol ; 49(3): 451-458, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32966632

RESUMO

BACKGROUND: Mammary neoplasms are common tumors in intact female dogs. Fine-needle aspiration cytology (FNAC) is a valuable diagnostic tool and has gained some credibility in the diagnosis of mammary tumors in dogs. Prompt classification of canine mammary tumors using cytology would enhance feasibility as a prognostic tool and guide clinical and surgical management. OBJECTIVES: We aimed to examine background elements to differentiate mammary tumors using FNAC. We proposed to distinguish simple from complex and mixed tumors by identifying myoepithelial (ME) cells and different types of extracellular matrix. Additionally, we determined the accuracy of FNAC to differentiate benign from malignant tumors. METHODS: One hundred and one mammary tumors from female dogs were included in this study. We compared FNAC using histopathology as the gold standard. Cellular and background components were evaluated and identified. The cytologic accuracy, sensitivity (Se), specificity (Sp), positive predictive value (PPV), and negative predictive value (NPV) for diagnosing malignancy were determined, excluding inadequate samples. RESULTS: The cytologic-histologic agreement was 92.5% for simple carcinomas, 57.9% for complex-type carcinomas, 57.1% for mixed-type carcinomas, 27.3% for carcinosarcomas, and 100% for osteosarcomas. Myoepithelial cells were successfully identified using FNAC. Myxoid and chondroid/osteoid matrix were satisfactorily recognized. Cytologic accuracy, Se, Sp, PPV, and NPV for diagnosing malignancy were 99%, 100%, 83%, 99%, and 100%, respectively. CONCLUSIONS: Chondroid/osteoid matrix was noted in mixed tumors but not in complex tumors. Myxoid matrix, often associated with ME cells, was noted in complex and mixed tumors. Mesenchymal cells were differentiated from ME cells, allowing the distinction of simple carcinomas with scirrhous reaction from complex and mixed tumors.


Assuntos
Doenças do Cão , Neoplasias Mamárias Animais , Animais , Biópsia por Agulha Fina/veterinária , Diferenciação Celular , Citodiagnóstico/veterinária , Doenças do Cão/diagnóstico , Cães , Matriz Extracelular/patologia , Feminino , Neoplasias Mamárias Animais/diagnóstico , Neoplasias Mamárias Animais/patologia
2.
Microb Pathog ; 107: 1-5, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28286151

RESUMO

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.


Assuntos
Estresse Oxidativo/fisiologia , Sporothrix/patogenicidade , Esporotricose/sangue , Esporotricose/metabolismo , Animais , Antioxidantes/análise , Biomarcadores/sangue , Catalase/sangue , Citocinas/sangue , Modelos Animais de Doenças , Granuloma/patologia , Hiperplasia , Inflamação/patologia , Interferon gama/sangue , Interleucina-6/sangue , Peroxidação de Lipídeos , Fígado/patologia , Masculino , Ratos , Soro/enzimologia , Baço/patologia , Esplenopatias , Esporotricose/patologia , Superóxido Dismutase/sangue , Testículo/patologia , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Fator de Necrose Tumoral alfa/sangue
3.
Biomed Pharmacother ; 84: 559-568, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27694000

RESUMO

The present study investigated the protective effect of quercetin (Querc) on memory, anxiety-like behavior and impairment of ectonucleotidases and acetylcholinesterase (AChE) activities in brain of streptozotocin-induced diabetic rats (STZ-diabetes). The type 1 diabetes mellitus was induced by an intraperitoneal injection of 70mg/kg of streptozotocin (STZ), diluted in 0.1M sodium-citrate buffer (pH 4.5). Querc was dissolved in 25% ethanol and administered by gavage at the doses of 5, 25 and 50mg/kg once a day during 40days. The animals were distributed in eight groups of ten animals as follows: vehicle, Querc 5mg/kg, Querc 25mg/kg, Querc 50mg/kg, diabetes, diabetes plus Querc 5mg/kg, diabetes plus Querc 25mg/kg and diabetes plus Querc 50mg/kg. Querc was able to prevent the impairment of memory and the anxiogenic-like behavior induced by STZ-diabetes. In addition, Querc prevents the decrease in the NTPDase and increase in the adenosine deaminase (ADA) activities in SN from cerebral cortex of STZ-diabetes. STZ-diabetes increased the AChE activity in SN from cerebral cortex and hippocampus. Querc 50mg/kg was more effective to prevent the increase in AChE activity in the brain of STZ-diabetes. Querc also prevented an increase in the malondialdehyde levels in all the brain structures. In conclusion, the present findings showed that Querc could prevent the impairment of the enzymes that regulate the purinergic and cholinergic extracellular signaling and improve the memory and anxiety-like behavior induced by STZ-diabetes.


Assuntos
5'-Nucleotidase/metabolismo , Acetilcolinesterase/metabolismo , Adenosina Desaminase/metabolismo , Ansiedade/prevenção & controle , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Transtornos da Memória/prevenção & controle , Memória/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Quercetina/farmacologia , Animais , Ansiedade/induzido quimicamente , Ansiedade/enzimologia , Ansiedade/psicologia , Encéfalo/enzimologia , Encéfalo/fisiopatologia , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/enzimologia , Diabetes Mellitus Experimental/psicologia , Diabetes Mellitus Tipo 1/induzido quimicamente , Diabetes Mellitus Tipo 1/enzimologia , Diabetes Mellitus Tipo 1/psicologia , Relação Dose-Resposta a Droga , Proteínas Ligadas por GPI/metabolismo , Masculino , Malondialdeído/metabolismo , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/enzimologia , Transtornos da Memória/psicologia , Atividade Motora/efeitos dos fármacos , Ratos Wistar , Estreptozocina
4.
Microb Pathog ; 97: 94-102, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27260685

RESUMO

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.


Assuntos
Colinesterases/análise , Inflamação/patologia , Sporothrix/crescimento & desenvolvimento , Esporotricose/patologia , Animais , Anticorpos Antifúngicos/sangue , Citocinas/análise , Modelos Animais de Doenças , Linfócitos/enzimologia , Masculino , Proteínas/análise , Ratos Wistar , Soro/enzimologia
5.
Antimicrob Agents Chemother ; 60(1): 87-91, 2016 01.
Artigo em Inglês | MEDLINE | ID: mdl-26459895

RESUMO

The present study investigated the in vitro and the in vivo interactions among azithromycin, clarithromycin, minocycline, and tigecycline against Pythium insidiosum. In vitro antimicrobial activities were determined by the broth microdilution method in accordance with CLSI document M38-A2, and the antibiotic interactions were assayed using the checkerboard MIC format. In vivo efficacy was determined using a rabbit infection model. The geometric mean MICs of azithromycin, clarithromycin, minocycline, and tigecycline against P. insidiosum were, respectively, 1.91, 1.38, 0.91, and 0.79 µg/ml. By checkerboard testing, all combinations resulted in in vitro synergistic interactions (>60%). Antagonism was not observed. The in vivo studies showed that azithromycin (20 mg/kg/day twice daily) alone or in combination with minocycline (10 mg/kg/day twice daily) significantly decreased the fungal burden. This study demonstrates that azithromycin possesses potent curative efficacy against subcutaneous pythiosis in the rabbit model.


Assuntos
Antifúngicos/farmacologia , Azitromicina/farmacologia , Claritromicina/farmacologia , Minociclina/análogos & derivados , Minociclina/farmacologia , Pitiose/tratamento farmacológico , Pythium/efeitos dos fármacos , Animais , Esquema de Medicação , Sinergismo Farmacológico , Quimioterapia Combinada , Testes de Sensibilidade Microbiana , Análise Multivariada , Pitiose/microbiologia , Pitiose/patologia , Pythium/genética , Pythium/crescimento & desenvolvimento , Pythium/isolamento & purificação , Coelhos , Pele/efeitos dos fármacos , Pele/microbiologia , Pele/patologia , Tigeciclina
6.
J Adv Res ; 6(6): 1079-82, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26644945

RESUMO

The aim of this study was to investigate the effects of Trypanosoma evansi infections on arterial blood gases of experimentally infected rats. Two groups with eight animals each were used; group A (uninfected) and group B (infected). Infected animals were daily monitored through blood smears that showed high parasitemia with 30 trypanosomes per field (1000×) on average, 5 days post-infection (PI). Arterial blood was collected at 5 days PI for blood gas analysis using an automated method based on dry-chemistry. Hydrogen potential (pH), partial oxygen pressure (pO2), oxygen saturation (sO2), sodium (Na), ionic calcium (Ca ionic), chlorides (Cl), partial dioxide carbon pressure (pCO2), base excess (BE), base excess in the extracellular fluid (BEecf), bicarbonate (cHCO3), potassium (K), lactate, and blood total dioxide the carbon (tCO2) were evaluated. The levels of pH, pCO2, BE, BEecf, cHCO3, and tCO2 were significantly decreased (P < 0.05) in group B compared to group A. Additionally, the same group showed increases in Cl and lactate levels when compared to uninfected group. Therefore, it is possible to state that the infection caused by T. evansi led to alterations in the acid-base status, findings that are correlated to metabolic acidosis.

7.
Pathol Res Pract ; 211(11): 851-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26376950

RESUMO

The aim of this study was to assess the role of the acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) as biomarkers of inflammation and tissue injury on rats experimentally infected by Cryptococcus neoformans. For this purpose, 20 male rats were divided into two groups: 10 animals representing the uninfected control group (Group A) and 10 C. neoformans var. grubii infected animals (Group B). Blood and brain samples were collected on days 10 (A10 and B10), and 30 (A30 and B30) post-infection (PI) for hematological analyses; AChE (in lymphocytes and brain) and seric BChE activity; interleukins (IL-1, IL-6, and IL-10); nitrite/nitrate (NOx) levels; and markers of protein oxidation (AOPP) and lipid peroxidation (TBARS). As a result, when animals of Group A were compared to animals of Group B, it was observed leukocytosis (P<0.05) on day 10 PI; AChE activity increase (P<0.05) in lymphocytes (day 30 PI) and in brain (days 10 and 30 PI); BChE activity decrease (P<0.05) on day 10 PI; IL-1 and IL-6 increase (P<0.01) in both periods, while IL-10 had reduced levels (P<0.01) in the same periods; NOx levels increased (P<0.05) significantly on days 10 and 30 PI, while AOPP and TBARS levels increased significantly on day 30 PI; as well as pneumonia on infected rats. Therefore, based on the results obtained, it was possible to conclude that AChE and BChE behavior lead to a proinflammatory reaction evidenced by the enhancement of IL-1, IL-6, and NOx throughout the experiment associated with reduction on IL-10 levels, and cellular damage.


Assuntos
Acetilcolinesterase/biossíntese , Biomarcadores/metabolismo , Butirilcolinesterase/biossíntese , Criptococose/patologia , Inflamação/patologia , Acetilcolinesterase/análise , Animais , Butirilcolinesterase/análise , Criptococose/enzimologia , Criptococose/imunologia , Cryptococcus neoformans , Modelos Animais de Doenças , Inflamação/enzimologia , Inflamação/imunologia , Masculino , Estresse Oxidativo/fisiologia , Ratos , Ratos Wistar
8.
Vet Parasitol ; 212(3-4): 123-9, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26223153

RESUMO

The aims of this study were to evaluate vertical transmission of Trypanosoma evansi in sheep experimentally infected, in addition to the mammary transmission by colostrum or milk of these infected sheep to mice. Three pregnant sheep were used: one uninfected, four months pregnant (Sheep A); and two (Sheep B and C) infected intravenously by T. evansi trypomastigotes (4.6×10(6) per animal) on the third (Sheep C) and fourth (Sheep B) month of pregnancy. Both infected sheep developed low and oscillating parasitemia measured by blood smears. Hemogram was performed at seven day intervals, showing anemia, leukocytosis, and lymphocytosis on sheep B and C. Three sheep had twins, where sheep A delivered healthy lambs and both infected sheep had delivered at least one stillborn. Additionally, lambs from sheep B and C died 24 and 72 h post-partum, respectively. Before colostrum intake, four lambs from infected sheep were positives for T. evansi according to blood smear evaluation, serology (CATT/T. evansi), and PCR. Sheep colostrum and milk samples collected from the first four days post-partum were positives for T. evansi on PCR, and these samples were able to infect seven mice (out of 10) orally (n=4/5) and intraperitoneally (n=3/5). Therefore, we conclude that the vertical transmission of T. evansi occurs in pregnant sheep, in addition to a strong possibility of the transmission by colostrum and milk.


Assuntos
Complicações Parasitárias na Gravidez/veterinária , Doenças dos Ovinos/parasitologia , Tripanossomíase/veterinária , Animais , Colostro/parasitologia , Feminino , Transmissão Vertical de Doenças Infecciosas/veterinária , Camundongos , Leite/parasitologia , Parasitemia/sangue , Parasitemia/veterinária , Gravidez , Complicações Parasitárias na Gravidez/parasitologia , Ovinos , Tripanossomíase/parasitologia , Tripanossomíase/transmissão
9.
Rev. MVZ Córdoba ; 20(1): 4455-4460, ene.-abr. 2015. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-957301

RESUMO

Objective. This study aimed to investigate the presence and activity of the ecto adenosine deaminase (E-ADA) enzyme in tachyzoites of Neospora caninum (Nc-1 strain), as well as to assess the activity of a well-known E-ADA inhibitor, the deoxycoformycin. Materials and methods. The parasites were grown in cell culture, being subsequently separated in a pellet of tachyzoites, on which the E-ADA activity was tested using the concentrations 0 (control), 0.2, 0.4 and 0.8 mg mL-1. Results. The E-ADA showed high activity, progressively increasing its activity according to the enhancement of the protein concentration. The test was carried out with different concentrations of deoxycoformycin, showing that it was able to inhibit the E-ADA present on the free form of the parasite. Conclusions. Based on these results we conclude that the E-ADA is present on tachyzoites of N. caninum, and deoxycoformycin is able to inhibit this enzyme. In this sense, knowing the negative impact of N. caninum on reproductive issue in cattle (mainly abortion), might it is an alternative in order to deal with this parasitic infection.


Objetivo. Este estudio tuvo como objetivo investigar la presencia y la actividad de la adenosina deaminasa (E-ADA) en taquizoitos de Neospora caninum (Nc-1 cepa), así como ensayar un conocido inhibidor de estas enzimas. Material y métodos. Los parásitos se multiplicaron en cultivo celular y posteriormente fueron separados en un sedimento de taquizoitos. La actividad de E-ADA fue probada en el parásito, usando concentraciones de 0 (control), 0.2, 0.4 y 0.8 mg mL-1. Resultados. El E-ADA tenía una alta actividad aumentó progresivamente de acuerdo con la concentración de proteínas. La prueba se llevó a cabo con diferentes concentraciones del inhibidor E-ADA (desoxicoformicina) y fue capaz de inhibir la presente E-ADA en el parásito. Conclusiones. Por la observación de los resultados se concluye que la enzima E-ADA está presente en taquizoítos de N. caninum, y desoxicoformicina es capaz de inhibir la acción de la enzima. En este sentido, conocer el impacto negativo del parásito en los problemas productivos y reproductivos en el ganado (principalmente abortos), estos resultados pueden ser una alternativa para evitar esta enfermedad parasitaria.

10.
Exp Parasitol ; 149: 39-46, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25499512

RESUMO

This study aimed to verify the effect of the treatment with A. satureioides essential oil (free and nanoencapsulated forms) and diminazene aceturate on hematological and biochemical variables in rats infected by Trypanosoma evansi. The 56 rats were divided into seven groups with eight rats each. Groups A, C and D were composed by uninfected animals, and groups B, E, F and G were formed by infected rats with T. evansi. Rats from groups A and B were used as negative and positive control, respectively. Rats from the groups C and E were treated with A. satureioides essential oil, and groups D and F were treated with A. satureioides nanoencapsulated essential oil. Groups C, D, E and F received one dose of oil (1.5 mL kg(-1)) during five consecutive days orally. Group G was treated with diminazene aceturate (D.A.) in therapeutic dose (3.5 mg kg(-1)) in an only dose. The blood samples were collected on day 5 PI for analyses of hematological (erythrocytes and leukocytes count, hemoglobin concentration, hematocrit, mean corpuscular and mean corpuscular hemoglobin concentration) and biochemical (glucose, triglycerides, cholesterol, alanine aminotransferase (ALT), aspartate aminotransferase (AST), albumin, urea and creatinine) variables. A. satureioides administered was able to maintain low parasitemia, mainly the nanoencapsulated form, on 5 days post infection. On the infected animals with T. evansi treated with A. satureioides essential oil (free and nanocapsules) the number of total leucocytes, lymphocytes and monocytes present was similar to uninfected rats, and different from infected and not-treated animals (leukocytosis). Treatment with A. satureioides in free form elevated levels of ALT and AST, demonstrating liver damage; however, treatment with nanoencapsulated form did not cause elevation of these enzymes. Finally, treatments inhibited the increase in creatinine levels caused by infection for T. evansi. In summary, the nanoencapsulated form showed better activity on the trypanosome; it did not cause liver toxicity and prevented renal damage.


Assuntos
Achyrocline/química , Diminazena/análogos & derivados , Óleos Voláteis/uso terapêutico , Óleos de Plantas/uso terapêutico , Tripanossomicidas/uso terapêutico , Tripanossomíase/tratamento farmacológico , Animais , Biomarcadores/sangue , Análise Química do Sangue , Diminazena/administração & dosagem , Diminazena/uso terapêutico , Cães , Feminino , Testes Hematológicos , Rim/fisiologia , Fígado/fisiologia , Nanocápsulas , Óleos Voláteis/administração & dosagem , Óleos Voláteis/química , Parasitemia/parasitologia , Óleos de Plantas/administração & dosagem , Óleos de Plantas/química , Ratos , Ratos Wistar , Tripanossomicidas/administração & dosagem , Trypanosoma/efeitos dos fármacos , Tripanossomíase/sangue
11.
Pathol Res Pract ; 210(12): 812-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25446248

RESUMO

The aim of this study was to evaluate the nitric oxide (NO) levels, and oxidative and antioxidant markers of lambs experimentally and naturally infected by Haemonchus contortus, and its relation to lesions in the abomasum. For experimental study, a total of 14 healthy lambs were divided into two groups with seven animals each. Group A represented the uninfected animals (control), and Group B was formed by infected animals with 15,000 larvae of H. contortus. Blood was collected on days 15, 45, and 75 post-infection (PI) to obtain serum for biochemical analysis: lactate dehydrogenase (LDH), nitrite/nitrate (NOx), advanced oxidation protein products (AOPP), and ferric reducing ability of plasma (FRAP). Parasitological stool examination (eggs per gram of feces--EPG) was performed on days 15, 45, and 75 PI to verify the evolution of the infection. On day 15 PI EPG was negative, but on days 45 and 75 PI the EPG was positive for animals from Group B. In the three periods evaluated it was observed an increase of LDH levels in serum of lambs infected with gastrointestinal nematodes, but on the other hand NOx levels were reduced on the same periods in infected animals. The AOPP and FRAP levels did not differ between groups on days 15 and 45 PI, but increased significantly on day 75 PI in infected lambs. The same variables were studied in 10 lambs naturally infected with helminths, where more than 97% corresponded to H. contortus (hematocrit and EPG values were 18.8 ± 2.5% and 7120 ± 2940, respectively). Similar to the experimental study, the levels of NOx reduced, and the levels of LDH, FRAP, and AOPP increased in serum of this animal associated inflammatory infiltrate in the mucosa of the abomasum. Therefore, during the infection by H. contortus it was observed alterations in oxidative markers, indicators of cell lesion confirmed by histological examination of the abomasum, and consequently there were changes in antioxidant levels, with the purpose of cell protection. We also conclude that helminth infection interferes with the nitric oxide metabolism.


Assuntos
Abomaso/parasitologia , Hemoncose/veterinária , Haemonchus/patogenicidade , Óxido Nítrico/metabolismo , Estresse Oxidativo , Doenças dos Ovinos/parasitologia , Abomaso/metabolismo , Abomaso/patologia , Produtos da Oxidação Avançada de Proteínas/sangue , Animais , Animais Recém-Nascidos , Antioxidantes/metabolismo , Biomarcadores/sangue , Modelos Animais de Doenças , Fezes/parasitologia , Hemoncose/sangue , Hemoncose/parasitologia , Hemoncose/patologia , Haemonchus/classificação , L-Lactato Desidrogenase/sangue , Masculino , Nitratos/sangue , Nitritos/sangue , Oxirredução , Ovinos , Doenças dos Ovinos/sangue , Doenças dos Ovinos/patologia , Fatores de Tempo
12.
Vet Microbiol ; 174(1-2): 206-13, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25278365

RESUMO

Cryptococcus neoformans, the etiological agent of cryptococcosis, is an opportunistic fungal pathogen of immunocompromised individuals. The aim of this study was to evaluate the activities of E-NTPDase and E-ADA in rats experimentally infected by C. neoformans var. grubii. Adult rats (35) were divided in two groups: 18 for the control group (uninfected) (A), and 17 for the infected group (B). Each group was separated into three sub-groups (A1, A2, A3-B1, B2, B3), and samples were collected on 10, 20, and 30 days post-infection (PI). Leukocyte counts, IFN-γ, TNF-α, IgM, IgG levels, and E-NTPDase and E-ADA activities were analyzed. It was possible to observe that IgG and IgM seric levels of infected rats were significantly elevated (P<0.01) on days 10, 20 and 30 PI, as well as the levels of TNF-α and INF-γ when compared to uninfected rodents. Regarding E-NTPDase activity in lymphocytes, it was possible to observe that the ATP hydrolysis was significantly decreased on days 20 (P<0.01) and 30 PI (P<0.05), while ADP hydrolysis was significantly reduced only on day 20 PI (P<0.01) when compared with uninfected group. Seric E-ADA activity had a significant reduction (P<0.01) during all three evaluated periods when compared to the control group, while E-ADA activity in lymphocytes increased significantly (P<0.01) when compared to the group A on day 10 PI; however on days 20 and 30 PI, its activity was considerable reduced in lymphocytes of infected animals (P<0.01). Therefore, it is possible to conclude that the infection caused by C. neoformans in immunocompetent rats leads to changes in the purinergic signaling (NTPDase and E-ADA), concomitantly with an inflammatory response (increased levels of cytokines and immunoglobulins) associated with inflammatory infiltrates and histological lesions in the lung.


Assuntos
Adenosina Desaminase/metabolismo , Antígenos CD/metabolismo , Apirase/metabolismo , Criptococose/enzimologia , Cryptococcus neoformans/imunologia , Animais , Criptococose/imunologia , Citocinas/sangue , Técnicas Histológicas , Contagem de Leucócitos , Linfócitos/metabolismo , Ratos , Fatores de Tempo
13.
Exp Parasitol ; 147: 1-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25300765

RESUMO

The aim of this study was to assess the effects of iron supplementation on oxidative stress and on the activity of the adenosine deaminase (ADA) in rats experimentally infected by Trypanosoma evansi. For this purpose, 20 rats were divided into four experimental groups with five animals each as follows: groups A and B were composed by healthy animals, while animals from groups C and D were infected by T. evansi. Additionally, groups B and D received two subcutaneous doses of iron (60 mg kg(-1)) within an interval of 5 days. Blood samples were drawn on day 8 post infection in order to assess hematological and biochemical variables. Among the main results are: (1) animals from group C showed reduced erythrogram (with tendency to anemia); however the same results were not observed for group D; this might be a direct effect of free iron on trypanosomes which helped to reduce the parasitemia and the damage to erythrocytes caused by the infection; (2) iron supplementation was able to reduce NOx levels by inhibiting iNOS, and thus, providing an antioxidant action and, indirectly, reducing the ALT levels in groups Band D; (3) increase FRAP levels in group D; (4) reduce ADA activity in serum and erythrocytes in group C; however, this supplementation (5) increased the protein oxidation in groups B and D, as well as group C (positive control). Therefore, iron showed antioxidant and oxidant effects on animals that received supplementation; and it maintained the activity of E-ADA stable in infected/supplemented animals.


Assuntos
Aminoidrolases/sangue , Anemia Ferropriva/prevenção & controle , Ferro/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Tripanossomíase/tratamento farmacológico , Tripanossomíase/metabolismo , Alanina Transaminase/sangue , Animais , Proteínas Sanguíneas/análise , Creatinina/sangue , Cães , Contagem de Eritrócitos , Eritrócitos/enzimologia , Hematócrito , Hemoglobinas/análise , Ferro/sangue , Contagem de Leucócitos , Masculino , Óxido Nítrico/sangue , Parasitemia , Ratos , Ratos Wistar , Tripanossomíase/complicações , Ureia/sangue
14.
Parasitology ; 141(13): 1761-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25111395

RESUMO

SUMMARY The aim of this study was to assess the effect of sulfamethoxazole/trimethoprim (ST) supplemented with diphenyl diselenide and sodium selenite in experimental toxoplasmosis, on oxidant/antioxidant biomarkers and cytokine levels. Eighty-four BALB/c mice were divided in seven groups: group A (negative control), and groups B to G (infected). Blood and liver samples were collected on days 4 and 20 post infection (p.i.). Levels of thiobarbituric acid (TBA) reactive substances and advanced oxidation protein products (AOPP) were assessed in liver samples. Both biomarkers were significantly increased in infected groups on day 4 p.i., while they were reduced on day 20 p.i., compared with group A. Glutathione reductase (GR) activity significantly (P<0·01) increased on day 4 p.i., in group G, compared with group A. INF-γ was significantly increased (P<0·001) in both periods, day 4 (groups B, C, F and G) and 20 p.i. (groups C, F and G). IL-10 significantly reduced (P<0·001) on day 4 p.i. in group B; however, in the same period, it was increased (P<0·001) in groups C and G, compared with group A. On day 20 p.i., IL-10 increased (P<0·001) in groups F and G. Therefore, our results highlighted that these forms of selenium, associated with the chemotherapy, were able to reduce lipid peroxidation and protein oxidation, providing a beneficial immunological balance between the production of pro- and anti-inflammatory cytokines.


Assuntos
Antioxidantes/metabolismo , Derivados de Benzeno/farmacologia , Compostos Organosselênicos/farmacologia , Selenito de Sódio/farmacologia , Toxoplasmose/metabolismo , Animais , Biomarcadores/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Peroxidação de Lipídeos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Oxidantes/metabolismo , Oxirredução , Estresse Oxidativo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
15.
Ticks Tick Borne Dis ; 5(5): 466-74, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24950853

RESUMO

Canine rangeliosis (popular names: "nambi-uvú", i.e. ``bleeding ears''; "peste de sangue", i.e. ``bleeding plague''; and "febre amarela dos cães", i.e. ``yellow fever of dogs'') is a tick-borne haemolytic and haemorrhagic disease caused by the protozoan parasite Rangelia vitalii which infects erythrocytes, leukocytes, and endothelial cells of blood capillaries. Rangelia vitalii was first reported as a novel piroplasm of dogs in 1910 in Brazil, a discovery that was met with skepticism at that time. Canine rangeliosis has been diagnosed in domestic dogs not only in Brazil but also in other South American countries (Argentina and Uruguay). Rangelia vitalii infection has also been found incidentally in Brazil in wild dogs (Cerdocyon thous, the crab-eating fox). Despite the fact that researchers in the early 1900s suggested that R. vitalii was a hitherto unidentified piroplasm that would be transmitted by the tick Amblyomma aureolatum, it was not until 2012 that these hypotheses were actually confirmed by PCR and transmission studies. Molecular studies have shown that R. vitalii is related to the Babesia sensu strictu clade, but genetically different from other morphologically similar species of Babesia that infect dogs. Another difference between Babesia spp. and R. vitalii is the ability of R. vitalii to invade endothelial cells, erythrocytes, and leukocytes. Experimental infection in dogs has successfully reproduced the clinical picture and pathology of the natural disease. In this article, epidemiology, clinical signs, laboratory findings, pathogenetic mechanisms including oxidative stress and immune response, necropsy findings, microscopic lesions, diagnosis, and treatment of canine rangeliosis are reviewed. What is currently known about this protozoal disease since its first report over a century ago is presented herein.


Assuntos
Doenças do Cão/microbiologia , Piroplasmida/isolamento & purificação , Infecções Protozoárias em Animais/parasitologia , Doenças Transmitidas por Carrapatos/veterinária , Animais , Brasil/epidemiologia , Doenças do Cão/epidemiologia , Doenças do Cão/história , Cães , História do Século XX , História do Século XXI , Infecções Protozoárias em Animais/epidemiologia , Infecções Protozoárias em Animais/história , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/história , Doenças Transmitidas por Carrapatos/parasitologia
16.
Pathol Res Pract ; 210(8): 526-32, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24951243

RESUMO

The objective of this study was to investigate the activity of acetylcholinesterase (AChE), nitrite/nitrate (NOx) levels, as well as the biomarkers of cellular damage in the brain of mice experimentally infected with Toxoplasma gondii. Sixty mice were divided into two experiments: in experiment I the mice were infected with T. gondii/RH strain, while in experiment II they were infected with T. gondii, strains VEG and ME-49. Our evaluations were carried out on brain homogenized samples, assessing the AChE and glutathione reductase (GR) activities, and NOx, TBARS and AOPP levels in all the infected animals, compared with the control group. In both experiments, I and II, it was observed an increase in the activity of AChE and GR, as well as in the levels of NOx in the brain of infected mice with T. gondii. TBARS levels were increased in mice infected with the three different strains, RH, ME-49, and VEG. AOPP concentration was increased only in mice infected with the RH strain. Animals infected with the strains VEG and ME-49 showed histological lesions, associated with the presence of the parasite in the brain. Therefore, the infection by T. gondii is able to interfere in cholinesterase activity and NO levels, in association with oxidative stress and histological lesion.


Assuntos
Acetilcolinesterase/metabolismo , Encéfalo/metabolismo , Óxido Nítrico/metabolismo , Toxoplasmose Animal/metabolismo , Toxoplasmose Cerebral/metabolismo , Animais , Encéfalo/patologia , Masculino , Camundongos , Estresse Oxidativo , Toxoplasma , Toxoplasmose Animal/patologia , Toxoplasmose Cerebral/patologia
17.
Res Vet Sci ; 96(3): 501-6, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24731531

RESUMO

This study aimed to evaluate the effect of tea tree oil (TTO - Melaleuca alternifolia) on hepatic and renal functions, and the immune response of rats infected by Trypanosoma evansi. A pilot study has shown that rats treated with TTO orally (1 ml kg(-1)) had increased survival rate without curative effect. In order to verify if increased longevity was related to a better immune response against T. evansi when using tea tree oil, a second experiment was conducted. Thus, twenty-four rats were divided into four groups. The groups A and B were composed of uninfected animals, and the groups C and D had rats experimentally infected by T. evansi. Animals from the groups B and D were treated orally with TTO (1 ml kg(-1)) for three days. Blood samples were collected to verify humoral response analysis for immunoglobulins (IgA, IgM, IgE, and IgG) and cytokines (TNF-α, INF-γ, IL-1, IL-6, IL-4, and IL-10) at days 0, 3, 5 and 15 post-infection (PI). TTO treatment caused changes in the immunoglobulins and cytokines profile, as well as the course of T. evansi infection in rats. It was found that the TTO was not toxic, i.e., hepatic and renal functions were not affected. Therefore, it is possible to conclude that TTO influences the levels of inflammatory mediators and has trypanocidal effect, increasing life expectancy of rats infected by T. evansi.


Assuntos
Imunidade Humoral/efeitos dos fármacos , Melaleuca/imunologia , Parasitemia/tratamento farmacológico , Óleo de Melaleuca/farmacologia , Trypanosoma/imunologia , Tripanossomíase/tratamento farmacológico , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Creatinina/sangue , Citocinas/sangue , Citocinas/imunologia , Imunoglobulinas/sangue , Imunoglobulinas/imunologia , Masculino , Parasitemia/imunologia , Parasitemia/parasitologia , Projetos Piloto , Ratos , Óleo de Melaleuca/administração & dosagem , Óleo de Melaleuca/uso terapêutico , Tripanossomíase/imunologia , Tripanossomíase/parasitologia , Ureia/sangue
18.
Parasitology ; 141(7): 898-903, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24534114

RESUMO

The aim of this study was to evaluate the purine levels of lambs experimentally infected with Haemonchus contortus. A total of 12 healthy lambs were divided into two groups, composed of 6 animals each: Group A represented the healthy animals (uninfected), while in Group B the animals were infected with 15 000 larvae of H. contortus. Blood was drawn on days 15, 45 and 75 post-infection (PI) in order to perform the purine analysis (ATP, ADP, AMP, adenosine, inosine, hypoxanthine, xanthine and uric acid) by high pressure liquid chromatography (HPLC) in serum. On day 15 PI a significant (P<0·05) increase in the levels of ATP and inosine was observed in the infected animals, unlike the levels of ADP, adenosine, xanthine and uric acid which were reduced. On day 45 PI a significant (P<0·05) increase in the ATP and xanthine levels in infected animals was observed, contrasting with reduced levels of ADP and uric acid. Finally, on day 75 PI an increase occurred in the levels of ATP, adenosine and hypoxanthine in infected lambs, concomitant with a reduction in the levels of ADP and uric acid (P<0·05). These changes in purine levels may influence the inflammatory process and the pathological events.


Assuntos
Hemoncose/veterinária , Haemonchus , Purinas/sangue , Doenças dos Ovinos/parasitologia , Animais , Fezes/parasitologia , Hemoncose/sangue , Hemoncose/parasitologia , Masculino , Ovinos , Doenças dos Ovinos/sangue
19.
Exp Parasitol ; 136: 68-73, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24275558

RESUMO

The objective of this study was to evaluate the pathogenesis of ascites in mice infected with Toxoplasma gondii and gerbils infected with Neospora caninum during the acute phase disease. For that, 12 gerbils [Experiment I: not infected/control (n=6) and infected (n=6)] and 12 mice [Experiment II: control (n=6) and infected (n=6)] were used. Infected gerbils and mice showed marked ascites on days 5-7 post-infection (PI), while the not-infected animals had not ascites. Peritoneal liquid was collected from the all mice with uninfected animals receiving 1.5mL of saline solution into their abdominal cavity, allowing the recovery of cavity liquid. As a result, it was possible to observe differences in physics, chemistry and cytological analysis of the fluid cavity of animals infected with N. caninum and T. gondii, when they were compared with uninfected animals, as well as between animals experimentally infected. Additionally both, N. caninum and T gondii, caused an increase in the levels of nitric oxide (NOx-nitrate/nitrite), protein oxidation (AOPP) and lipid peroxidation (TBARS), while serum total protein and albumin were reduced in infected gerbils and mice. Gerbils infected with N. caninum showed multiple large cells with multilobulated nucleus, lytic necrosis and abundant amount of eosinophilic cytoplasm into the hepatic parenchyma. By the other hand, mice infected with T. gondii developed myriad foci of lytic necrosis combined with tachyzoites and cysts containing bradyzoites in liver. Both experimental models for N. caninum and T. gondii showed inflammatory foci and tachyzoites the peritoneum, which could be a major cause of ascites. Toxoplasmosis and neosporosis were able to cause clinical signs in experimental models with similar alterations in peritoneal fluid; however the toxoplasmosis histological changes were much more evident. Therefore, the pathogenesis of ascites appears to be directly related to liver damage, which strongly suggests alteration in the normal production of proteins as observed in this study, along with peritonitis.


Assuntos
Líquido Ascítico/química , Líquido Ascítico/citologia , Coccidiose/patologia , Fígado/patologia , Neospora , Toxoplasmose/patologia , Músculos Abdominais/patologia , Doença Aguda , Produtos da Oxidação Avançada de Proteínas/análise , Albuminas/análise , Animais , Modelos Animais de Doenças , Gerbillinae , Fígado/parasitologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico/análise , Peritônio/patologia , Proteínas/análise , Baço/patologia , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Toxoplasma , Toxoplasmose/metabolismo
20.
Parasitology ; 140(11): 1432-41, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23965823

RESUMO

The aim of this study was to investigate neurochemical and enzymatic changes in rats infected with Trypanosoma evansi, and their interference in the cognitive parameters. Behavioural assessment (assessment of cognitive performance), evaluation of cerebral L-[3H]glutamate uptake, acetylcholinesterase (AChE) activity and Ca+2 and Na+, K+-ATPase activity were evaluated at 5 and 30 days post infection (dpi). This study demonstrates a cognitive impairment in rats infected with T. evansi. At 5 dpi memory deficit was demonstrated by an inhibitory avoidance test. With the chronicity of the disease (30 dpi) animals showed anxiety symptoms. It is possible the inhibition of cerebral Na+, K+-ATPase activity, AChE and synaptosomal glutamate uptake are involved in cognitive impairment in infected rats by T. evansi. The understanding of cerebral host­parasite relationship may shed some light on the cryptic symptoms of animals and possibly human infection where patients often present with other central nervous system (CNS) disorders.


Assuntos
Ansiedade/parasitologia , Interações Hospedeiro-Parasita , Trypanosoma/fisiologia , Tripanossomíase/fisiopatologia , Acetilcolinesterase/metabolismo , Animais , Ataxia , Comportamento Animal , ATPases Transportadoras de Cálcio/metabolismo , Transtornos Cognitivos , Cães , Ácido Glutâmico/análise , Humanos , Masculino , Aprendizagem em Labirinto , Sistema Nervoso/química , Parasitemia , Ratos , Ratos Wistar , ATPase Trocadora de Sódio-Potássio/metabolismo , Trítio/análise , Tripanossomíase/parasitologia
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