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Adrenalectomies for canine adrenal tumours are associated with peri-operative morbidity and mortality. Objectives of this study included assessing the prognostic value of tumour- or surgery-related variables in predicting peri-operative mortality and overall survival in dogs undergoing adrenalectomies for primary adrenal tumours as well as pre-treatment with phenoxybenzamine on survival to discharge with pheochromocytomas specifically. A multi-institutional retrospective cohort study was performed across nine institutions. Electronic medical record searches identified 302 dogs which met the inclusion criteria. Data collected included dog-related, tumour-related, treatment-related, surgery-related, and outcome variables. Univariate and multivariable logistic regression and cox proportional hazards models were used to identify variables associated with death prior to discharge and tumour-related survival. Overall, 87% of dogs survived to discharge with a tumour-related survival time of 3.96 years. Post-operative complications were reported in 25%. Increased surgical time (p = 0.002) and pre-surgical medical treatment other than phenoxybenzamine (p = 0.024) were significantly associated with increased peri-operative mortality while ureteronephrectomy (p = 0.021), post-operative pancreatitis (p = 0.025), and post-operative aspiration pneumonia (p < 0.001) were significantly associated with decreased overall survival. Phenoxybenzamine pretreatment had no effect on peri-operative mortality. Thirty-seven of 45 (82%) dogs with pheochromocytomas not pretreated survived to discharge, and 50 of 59 (85%) dogs with pheochromocytomas pretreated with phenoxybenzamine survived to discharge (p = 0.730). This study provides information on risk factors for death prior to discharge and tumour-related survival that may help guide clinical management and owner expectations. In addition, the study findings challenge the previously reported benefit of phenoxybenzamine for pretreatment of dogs undergoing adrenalectomies for pheochromocytomas.  相似文献   
23.
Hepatozoon canis is a tick-borne protozoan that infects dogs and has been reported throughout the world. Manifestation of H. canis infection varies from being sub-clinical in apparently healthy dogs to severe illness. The main vector of the infection is the dog tick, Rhipicephalus sanguineus although other species may also transmit this agent. H. canis has been reported previously in Brazil, but mostly as an occasional finding during laboratory exams and always associated with other diseases. The prevalence of H. canis in dogs of rural areas of Brazil has been little studied. For this study, 250 dogs from seven counties of Rio de Janeiro state were examined. All the dogs were from rural areas, near forest. Of the dogs examined, 26 dogs were from Seropédica, 82 from Itaguaí, 41 from Paracambi, 26 from Mangaratiba, 32 from Barra do Piraí, 32 from Piraí and 11 from Miguel Pereira. Blood smears from the peripheral blood of the ear were taken and ticks found on the dogs were collected for identification in the laboratory. Using blood smear evaluation, H. canis was identified in 39.2% of the animals examined. Other hemoparasites identified were Babesia canis (5.2%) and Ehrlichia canis (4.8%). Four tick species were found parasitizing the dogs: Amblyomma cajennense (23.6%), R. sanguineus (12.4%), Amblyomma aureolatum (2.8%) and Amblyomma ovale (2.0%). There was a positive correlation between the presence of A. cajennense and H. canis infection.  相似文献   
24.
ABSTRACT The secreted phosphatase activities of two trypanosomatid parasites were characterized and compared with supernatants of living cells. The plant parasite Phytomonas fran?ai and the phytophagous hemipteran parasite Herpetomonas sp. hydrolyzed p-nitrophenylphosphate at a rate of 15.54 and 6.51 nmol Pi/mg of protein per min, respectively. Sodium orthovanadate (N(a)VO(3)) and sodium fluoride (NaF) decreased the phosphatase activities. The phosphatase activity of P. fran?ai was drastically diminished (73% inhibition) in the presence of sodium tartrate, whereas the phosphatase activity of Herpetomonas sp. was inhibited by 23%. Cytochemical analysis showed the localization of these enzymes on the external surface and in the flagellar pocket of the two trypanosomatids. Sodium tartrate inhibited this reaction, confirming the biochemical data. Platelet-activating factor modulated the phosphatase activities, inhibiting P. fran?ai activity and stimulating Herpetomonas sp. phosphatase activity.  相似文献   
25.
A new rot caused by a binucleate Rhizoctonia sp. affecting the tuberous root cortex of the domesticated yacon ( Smallanthus sonchifolius ) has been observed in Brazil. Isolates of a binucleate Rhizoctonia sp. were collected from roots with rot symptoms and characterized by the number of nuclei per cell, hyphal anastomosis, RAPD molecular markers, ITS-5·8S rDNA sequence and pathogenicity tests. All isolates had a mean of 1·9–2·2 nuclei per cell and anastomosed with the binucleate Rhizoctonia sp. AG G-tester strain. RAPD analysis was carried out between 11 isolates recovered from yacon and 11 AG (A, Ba, Bb, Bo, C, D, F, G, O, P, Q) standard testers of binucleate Rhizoctonia sp. Genetic similarities of 94·8–100% were observed among isolates of the binucleate Rhizoctonia sp. from yacon and all isolates were genetically more closely related to the AG G tester than other strains according to upgma analysis using RAPD markers. Homologies of complete ITS nucleotide sequences were 100% between binucleate isolates of Rhizoctonia sp. from yacon and the AG G tester. According to pathogenicity tests, the isolates caused typical rot symptoms of yacon tubers 90 days after inoculation  相似文献   
26.
Factors associated with bovine leptospirosis in Rio de Janeiro, Brazil   总被引:3,自引:0,他引:3  
Serum samples from 379 adult cows with lowered fertility farmed in the Rio de Janeiro region of Brazil. They were examined for Leptospira antibodies. A questionnaire was completed for each herd. Antibodies were detected in 46.9% of these cows, mainly to serovar hardjo. Main risk factor associated with seropositivity was co-grazing with other species, mainly pigs (OR = 3.17; p<0.04). Absence of or infrequent veterinary assistance (OR = 1.74) has also been suggested to be associated to the overall seroprevalence to leptospirosis. We suggest that a successful control programme for bovine leptospirosis should include a complete investigation of herd management practices, which could influence in the occurrence of the infection.  相似文献   
27.
In this paper, important connections between the two main contingents of the autonomic nervous system, intrinsic and extrinsic visceral plexus were analysed. Concerning heart innervation, the territories of extrinsic innervation are very important in the treatment of congenital or acquired cardiopathy, thoracic neoplasia and aortic arch persistence, among others. This research compared young and adult extrinsic cardiac innervation and described the surgical anatomic nerve segments. Animals were perfused with a 10% formaldehyde solution in PBS (0.1 m) (pH 7.4) and submitted to macro- and meso-scopic dissection immersed in 60% acetic acid alcoholic solution and 20% hydrogen peroxide aqueous solution. The nerve segments were assigned as: right vagus nerve segment, left vagus nerve segment, right middle cervical ganglion segment, left middle cervical ganglion segment, right caudal laryngeal nerve segment, left caudal laryngeal nerve segment, right phrenic nerve segment and left phrenic nerve segment.  相似文献   
28.
Sixty-three Escherichia coli strains isolated from broilers with respiratory problems were examined for virulence factors, hemolysin synthesis ability, motility, hemagglutination capacity, operon pap presence, colicin production, and serum resistance. The capacity to hemagglutinate guinea pig erythrocytes was found in 53 (84.1%) of the samples, but only 30 (47.6%) agglutinated chicken erythrocytes. D-mannose-sensitive hemagglutination against guinea pig erythrocytes was found in 19 (30.2%) samples and against chicken erythrocytes, in 15 (23.8%) samples, whereas the D-mannose-resistant hemagglutination with guinea pig erythrocytes was found in 34 (54%) samples, and 13 of these (20.6%) showed this characteristic against chicken erythrocytes. Operon pap, P fimbria codifier, was detected in 26 samples in a total of 34 D-mannose-resistant samples. Colicin production was observed in 55 (87.3%) of the strains, and 41.8% presented V colicin production. Of the samples analyzed, 56 (88.9%) presented serum resistance, six (9.5%) were intermediate, and only one (1.6%) was sensitive to the action of the complement. The diversity of virulence profiles detected in the samples in this study explains in part the multifactorial characteristics of avian colibacillosis.  相似文献   
29.
Ivermectin, a mixture of 22,23-dihydroavermectin B1a (80%) and B1b (20%), is produced by Streptomyces avermectilis, an actinomycete. It is a macrocyclic lactone disaccharide, a member of the avermectin family, and is used as an antiparasitic drug. Previous studies performed in our laboratory showed that doramectin, another avermectin drug, interferes with GABAergic-related behaviours, leading to anxiety and seizures. The objective of the present study was to examine the effects of ivermectin (0.5 and 1.0 mg/kg) on the central nervous system of rats, using behavioural models related to GABAergic neurotransmission. A known anxiolytic drug, diazepam, was used as a positive control. Open field and elevated plus-maze behaviours, as well as conflict behaviour to a conditioned response, were assessed. The effects of ivermectin and diazepam in reversing the anxiety induced by picrotoxin was studied. The protective effects of ivermectin on pentylenetetrazole- and picrotoxin-induced seizures were also investigated. In the open field, 1.0 mg/kg ivermectin decreased locomotion frequency at 15 and 60 min of observation, rearing behaviour showed a biphasic effect at 15 and 30 min and duration of immobility was increased in all sessions after 1.0 mg/kg ivermectin. These data suggest anxiolytic or sedative effects. Ivermectin and diazepam both had a tendency to cause an increase both in the number of entries into the open arms and on the time spent in the open arms of an elevated plus-maze. Picrotoxin on its own reduced the number of entries as well as the time spent in the open arms. Both diazepam and ivermectin reversed these effects of picrotoxin. In conflict behaviour analysis, ivermectin and diazepam gave the classic effect of an anxiolytic drug, reversing the conditioned response to shock. Ivermectin protected rats from the convulsant effects of pentylenetetrazole but not from those of picrotoxin. Thus, ivermectin had the pharmacological profile of an anxiolytic drug with GABAergic properties. The lack of effect on seizures induced by picrotoxin suggests that the action of ivermectin is different from that of the benzodiazepine drugs.  相似文献   
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