Veronica Machado Rolim

Acaricidal activity of limonene, limonene oxide and β-amino alcohol derivatives on Rhipicephalus (Boophilus) microplus

Limonene, limonene oxide and eight beta-amino alcohol derivatives obtained by synthesis were investigated for the effect on egg hatchability and mortality rates of newly hatched larvae of the cattle tick Rhipicephalus (Boophilus) microplus. At the doses between 10 microg/ml and 2.5 microg/ml all the compounds were highly lethal to the larvae and some of them showed activity at lower concentrations. The effect on the eggs hatchability was observed in all the treatments.

Clinical, pathological, immunohistochemical and molecular characterization of feline chronic gingivostomatitis

Objectives This study presents the clinical, pathological, immunohistochemical and molecular characterization of 26 cats with feline chronic gingivostomatitis (FCG). Methods Oral mucosal biopsies, blood and swabs were collected from cats presenting with oral lesions. The tissue sections were submitted for histopathology and immunohistochemical analysis for feline calicivirus (FCV), feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV). The swabs were subjected to PCR analysis for FCV, and blood for FeLV and FIV. Results The main clinical findings were dysphagia (88.2%), halitosis (76.5%), sialorrhea (47.1%), weight loss (41.2%), intense oral discomfort (35.3%), oral hemorrhage (17.6%), and lackluster and fragile coat (11.8%). Gross inspection revealed bilateral lesions across the palatoglossal fold to the lateral tongue base. The lesions were diffuse, proliferative, intensely red and friable, and bled easily upon examination in 80.8% of cases. In 23.1% of cases, the lesions were multifocal to coalescent, at times forming multiple vesicles on a reddened, edematous palatoglossal fold. Microscopic examination showed that 15.4% of lesions had moderate (grade 2) and 84.6% had severe (grade 3) inflammation. Immunohistochemistry revealed the presence of FeLV antigens in the epithelium and the inflammatory infiltrate of 30.8% of the cats with FCG. FCV antigens were not detected in the FCG lesions. Conclusions and relevance The FCG cases analyzed could not be correlated with FCV. It is possible that FeLV plays a role as a causal agent of lesions in cases where the presence of the virus has been confirmed by immunohistochemistry in epithelial samples.

Fatal systemic toxoplasmosis in Valley quail (Callipepla californica)

Highlights • This is the first report of systemic fatal toxoplasmosis in Valley quail.• Toxoplasma gondii was molecularly identified as belonging to ToxoDB-PCR-RFLP #87.• It caused a generalized disease with necrotic lesion in liver, heart, spleen, lungs, trachea and bone marrow, with large numbers of tachyzoites stained positively with polyclonal antiserum to T. gondii.

Treatment of dilated cardiomyopathy in rabbits with mesenchymal stem cell transplantation and platelet-rich plasma

Dilated cardiomyopathy (DCM) is a major cause of cardiovascular mortality and morbidity, and there is evidence to suggest that stem cell transplantation may be a viable treatment option for this condition. Therefore, the goal of the present study was to assess myocardial regeneration in rabbits with doxorubicin-induced DCM treated with adipose mesenchymal stem cells (MSC) alone or in combination with platelet-rich plasma (PRP). Twenty New Zealand rabbits received doxorubicin for the induction of DCM and were divided into four groups according to treatment: saline, MSC, PRP and MSC + RP. Treatment agents were injected directly into the left ventricular myocardium following a thoracoscopy. Rabbits were assessed through echocardiographic and electrocardiographic examinations, as well as serum cardiac troponin I measurements at baseline, after the induction of DCM and 15 days after treatment. Animals were euthanased following the last assessment, and hearts were collected for histopathological analyses. The MSC group showed improvements in all parameters assessed, while the PRP group showed significantly impaired heart function. Histopathology of the heart revealed that the MSC group displayed the lowest number of lesions, while rabbits in the MSC + PRP, saline and PRP groups had steadily advancing lesions. These results suggest that MSC transplantation can improve heart function in rabbits with DCM, and underscore the need for further studies of the effects of PRP on the myocardium.

Diagnóstico imuno-histoquímico e caracterização anatomopatológica de Mycoplasma gallisepticum em galinhas de subsistência

Avian mycoplasmosis is caused by bacteria from the Mycoplasmataceae family. Mycoplasma gallisepticum (MG) is the most pathogenic and economically significant species affecting poultry. The aim of this study was to use the immunohistochemistry technique (IHC) as a diagnostic method for the MG infection in poultry. In this report we described two outbreaks of mycoplasmosis caused by MG in free-range chickens. Clinical signs were characterized by prostration, decreased appetite, difficult breathing, nasal and ocular discharge. Necropsy findings were serous secretion in conjunctiva (7/10) and seioses (4/10), edema and caseous exudate; air sacs thickened with foam and caseous exudate (6/10); trachea diffusely reddish (4/10); lungs with 0.5 cm whitish spots (2/10); and pericardial sac with fibrin exudate (2/10). Histologically was observed a lymphoplasmacytic hyperplastic acute tracheitis (10/10), seiositis (5/5) and conjunctivitis (3/4); fibrinonecrotic bronchopneumonia (5/10); acute fibrinous pericarditis (2/10); and fibrinonecrotic aerosaculitis (1/1). IHC anti-MG stained in the extracellular surface of ciliated brush border and/or in the top of epithelium of trachea (10/10), bronchi (5/10) and sinuses (4/5). In seven out of ten cases it was possible to detect MG by real-time PCR from tracheal swabs. IHC anti-MG used as a diagnostic method showed good correlation with clinical signs, lesions and real-time PCR results.

Rectal stenosis in pigs associated with Salmonella Typhimurium and porcine circovirus type 2 (PCV2) infection

Rectal stricture is an acquired annular fibrous constriction of the rectum that results from a variety of chronic necrotizing enteric diseases. In pigs, it is in most cases a sequel of Salmonella infection. Porcine circovirus type 2 (PCV2) is a known pathogen causing immunosuppression in pigs worldwide. PCV2 infected pigs may be predisposed to salmonellosis. In this report, rectal stenosis was observed in 160 pigs from a herd that experienced an outbreak of enteric salmonellosis over a 4-month period. Distension of the abdominal wall and diarrhea were the main clinical signs observed. Five animals were analyzed showing annular cicatrization of the rectal wall 5.0-7.0 cm anterior to the anorectal junction and Salmonella-positive immunostaining in the large intestine. Salmonella Typhimurium was isolated from fragments of the large intestine. Porcine circovirus type 2 antigen was observed in the mesenteric lymph-node in 4 pigs and in the large intestine in 3 pigs.

Piglet colibacillosis diagnosis based on multiplex polymerase chain reaction and immunohistochemistry of paraffin-embedded tissues.

Enterotoxigenic Escherichia coli (ETEC) causes diarrhea in pigs, referred to as colibacillosis. The aim of this study was to optimize multiplex polymerase chain reaction (PCR) and immunohistochemistry (IHC) analyses of paraffin-embedded material to detect pathogenic E. coli strains causing colibacillosis in pigs. Multiplex PCR was optimized for fimbriae (F18, F4, F6, F5, and F41) and toxins (types A and B heat-stable toxins [STaP and STb], heat-labile toxin [LT], and type 2 Shiga toxin [STx2e]), and IHC was optimized for an anti-E. coli polyclonal antibody. Samples (132) from pigs received between 2006 and 2014 with clinical and histopathological diagnoses of colibacillosis were analyzed. E. coli was detected by IHC in 78.7%, and at least one virulence factor gene was detected in 71.2%. Pathogenic strains of ETEC with at least one fimbria and one toxin were detected in 40% of the samples in multiplex PCR. The most frequent virulence types were F18-STaP (7.5%), F18-STaP-STb (5.7%), and F4-STaP (3.8%). A statistically significant association was noted between virulence factors F4, F18, STaP, and STb and positive immunostaining results. Colibacillosis diagnosis through multiplex PCR and IHC of paraffin-embedded tissues is a practical approach, as samples can be fixed and stored for long periods before analysis.

Trema micrantha como causa de pneumopatia tóxica em ovinos: reprodução experimental

This paper describes the experimental Trema micrantha poisoning in sheep. Four from five sheep showed marked respiratory distress and death after ingestion of the third dose of plant leaves. The most frequent clinical findings were tachypnea, dyspnea, rhythmic contraction of the nostrils, cyanotic mucous membranes, mucous nasal discharge, hyperthermia, abdominal distension, increased volume and crepitation of parotid region, walking with the legs kept away laterally and sternal recumbency. T. micrantha proved to be toxic to sheep at 20 to 50g/kg bodyweight. At necropsy, we observed cyanotic mucous membranes, subcutaneous emphysema in the ventral area of cervical region or dorsal mediastinum, heavy and collapsed lungs with rib markings, red frothy fluid in the lumen of the trachea and primary bronchi, and several subpleural petechiae. Microscopic examination of lung tissue sections revealed that the tissue was characterized by thickening of the alveolar septa by diffuse type II pneumocytes proliferation, conferring an adenomatous appearance to some areas. These pneumocytes had large and hyperchromatic, sometimes bizarre nucleus or were multinucleate, with evident nucleoli. In some areas desquamated pneumocytes were found in the alveolar lumen, sometimes forming syncytia. There also was bronchiolar epithelium proliferation, conferring to the mucosa more than one epithelial cell layer, these cells had large and hyperchromatic nuclei and reduction in the amount of cilia. The proliferative changes of pneumocytes and bronchiolar epithelium were evaluated by anti-cytokeratin and anti-Ki-67 immunostaining. In order to differentiate pneumocytes and alveolar macrophages, we used anti-monocyte marker (MAC387). One sheep showed clinicopathological findings of acute liver failure with hepatocellular necrosis after ingestion of 25g/kg T. micrantha. The experimental poisoning by T. micrantha in sheep resulted in predominantly respiratory clinicopathological findings, confirming the results of spontaneous poisoning.

Melanoma amelanótico em cães: estudo retrospectivo de 35 casos (2004-2010) e caracterização imuno-histoquímica

Melanomas are aggressive tumors of melanocytes. They are common in dogs and involve mainly the oral cavity, mucocutaneous junction, and skin. Furthermore, these tumors could be highly pigmented or lack pigment. The biopsies archives from SPV-UFRGS, 2004 to 2010, were retrieved and melanocytic neoplasms in dogs were revised. A retrospective study of 35 cases of amelanotic melanomas (AM) was performed, also immunohistochemistry (IHC) characterization was evaluated. The dogs more affected were mixed breed followed by Poodle, Dachshund and Cocker Spaniel. The average age of the dogs was 10.7 years (5-18 years in age) and there was no sex predilection. The locations of the neoplasms were the oral cavity (57.1%) and digits (17.1%). Histologically, 40% were classified as epithelioid, 34.3% mixed and 25.7% spindle. The positive immunostaining for vimentin, S-100 protein and melan-A were 86.6%, 70%, and 56.6% respectively. These results indicated the most affected dogs with AM were elderly. Epiteliod classification was the most observed histologically. It is important to perform IHC, due to lacking of differentiation of AM, mainly, anti S-100 protein that showed to be the best option of positive marker, even better to Melan-A.

Adipose-derived stem cells improve full-thickness skin grafts in a rat model

To investigate the effects of heterologous adipose-derived stem cells (ADSCs) on autologous full-thickness skin grafts, we designed a first-intention healing model using Wistar rats. We harvested and sutured two full-thickness skin grafts in the dorsal recipient beds of 15 rats, randomized into three groups. In the treatment group, 1 × 106 ADSCs resuspended in saline solution (200 μL) were administered subcutaneously to the skin graft. The control group received only saline solution subcutaneously, whereas the negative control group did not receive any treatment. Compressive dressings were maintained until postoperative day 5. The grafts were assessed by two observers, who checked for the presence of epidermolysis on day 14. Planimetry showed the relative areas of normal skin, redness, ulceration, and contraction. Graft samples were obtained on day 14 and stained with hematoxylin and eosin and Massons trichrome. Epidermal analysis evaluated thickening, keratosis, acanthosis, hydropic degeneration, and inflammatory infiltrate. Dermal evaluation investigated the absence of hair follicles, granulation tissue formation, presence of inflammatory infiltrate, and collagen deposition. Immunohistochemistry was performed for dermal anti-VEGF and epidermal anti-Ki-67 staining. The ADSC group presented better macroscopic aspects, lower incidence of epidermolysis, and less loss of hair follicles. In addition, the ADSC group presented the lowest frequency of histopathological changes in the dermis and epidermis, as well as the largest subcutaneous and granulation tissue VEGF averages and the weakest Ki-67 staining of the epidermal basal layer. Subcutaneous administration of ADSCs may improve the integration of skin grafts, reducing the deleterious effects of ischemia and reperfusion injury.