Effects of heterologous platelet-rich plasma gel on standardized dermal wound healing in rabbits

PURPOSE

To evaluate the potential of heterologous platelet-rich plasma (PRP) gel for surgical skin wound healing in rabbits.

METHODS

Blood from a single healthy dog was used for PRP production, with calcium gluconate added to the PRP to form the gel. Two surgical excisions, one to the right and the other to the left of the dorsal midline, were made in six rabbits. One side was randomly allocated to topical application of a physiological solution, and the other was allocated to treatment with heterologous PRP gel. Clinical assessments (weight, pain sensitivity, coloring, edema, hyperemia, exudation, crust, and granulation) and morphometric evaluations were performed 0, 3, 7, 10, 14, and 17 days postoperatively. Histological analysis was performed on the 17th day.

RESULTS

With the exception of the presence of a crust at day 10, clinical variables did not differ significantly between the experimental groups. In both the control and PRP-treated groups, differences were identified when comparing time-points in terms of wound area reduction. Histological results indicated no significant differences between the control group and the PRP-treated group.

CONCLUSION

Heterologous platelet-rich plasma gel promoted dermal wound healing in rabbits with no adverse effects.

Comparison of experimentally-induced wounds in rabbits treated with different sources of platelet-rich plasma

Over the years, autologous platelet-rich plasma (PRP) has been used to great advantage in the healing of acute and chronic wounds. However, it is impossible to use in some situations so alternative PRPs need to be considered, such as homologous or heterologous PRPs. In order to evaluate the effects of PRP in the form of autologous, heterologous and homologous gels on in vivo cutaneous wound healing, 18 animals divided into three groups of six, were used for the study, with another six animals used as PRP donors. For the heterologous group an adult, mixed breed dog was used to obtain the PRP. The wounds were induced using an 8 mm punch. The left side was treated with NaCl 0.9%® (A) and a PRP gel was applied (GA = autologous; GHE = heterologous and GHO = homologous) on the right side (B). The wounds were evaluated for a period of 17 days. On the 17th day biopsies were taken for histopathological assessment of the wounds. The percentage of contraction was evident in side B (treated), which was confirmed in the microscopic analysis of the histological sections. Thus, it was concluded that PRP, regardless of the source, improves and accelerates the healing process, demonstrating its therapeutic potential on cutaneous lesions and its use in patients with impaired wound healing.

Kinetics and avidity of anti-Toxocara antibodies (IgG) in rabbits experimentally infected with Toxocara canis

An evaluation was made of the kinetics and avidity of anti-Toxocara antibodies (IgG) in rabbits experimentally infected with embryonated Toxocara canis eggs. Seventeen four month old New Zealand White rabbits were distributed into two groups. In the experimental group, twelve rabbits were infected orally with 1,000 embryonated T. canis eggs. A second group (n = 5), uninfected, was used as a control. Serum samples were collected for analysis on days 7, 14, 21, 28 and 60 post-infection (DPI). An indirect ELISA test was performed to evaluate the reactivity index (RI) of IgG anti-T. canis antibodies and to calculate the avidity index (AI). The animals showed seroconversion from the 14th DPI, with high AI (over 50%) except for one animal, which presented an intermediate AI. At 60 DPI, all the animals were seropositive and maintained a high AI. The data indicated that specific IgG antibodies formed early (14 DPI) in rabbits infected with T. canis, with a high avidity index that persisted throughout the course of the infection.

Cardiac markers: profile in rats experimentally infected with Toxocara canis

The aim of this study was to evaluate the profile of the enzymes creatine kinase (CK), creatine kinase MB (CK-MB) and lactate dehydrogenase (LDH) in Wistar rats infected with 250 (GI, n = 24) or 1000 (GII, n = 24) Toxocara canis eggs. Animals were evaluated on days 7, 15, 30, 60, 120 and 180 post-infection (DPI). Only the GI rats showed an increase in CK and CK-MB, at 15 and 30 DPI, respectively. Anti-Toxocara spp. antibodies were detected by ELISA in infected animals. Despite of the presence of eosinophilic infiltrate in the heart of three infected animals, none larva was recovered from the organ neither by acid digestion nor by Baermann procedure. Eosinophilia was observed in both groups but there was no significant difference in the eosinophil counts between GI and GII (p = 0.2239). It is possible to consider that cardiac lesion is an eventual finding in murine model for toxocariasis.

Effect of Mikania glomerata (Asteraceae) leaf extract combined with anti-venom serum on experimental Crotalus durissus (Squamata: Viperidae) envenomation in rats

Crotalic envenomation represents the highest number of deaths when compared to other snakebite envenomations of medical interest. Crotalic venom has important characteristics such as neurotoxicity, myotoxicity, nephrotoxicity, and clotting and hemolytic action. We evaluated the clinical and laboratory aspects of Crotalus durissus terrificus experimental envenomation in Wistar rats treated with antivenom and the aqueous extract of the plant Mikania glomerata. The animals were divided into three groups: Group C (control); Group VS-venom and antivenom; Group VSM-venom, antivenom and aqueous extract of M. glomerata. Crotalic poison caused clinical and laboratory alterations in Wistar mice. Significant clinical alterations were: temperature decrease, edema in the venom inoculated member, sedation and a locomotion decrease in groups VS and VSM when compared with group C. A faster recovery from sedation was observed only for animals of group VSM when compared to VS. There was an increase in the number of leukocytes, neutrophils and creatine kinase in the VS and VSM groups, compared to group C. Wistar rats showed a high resistance to crotalic venom. Additional studies with different doses, time of treatment, different administration methods and histopathological and immunological studies are necessary to understand the action of M. glomerata in crotalic accidents.

EFFECTS OF RESVERATROL ON LIVER FUNCTION OF OBESE FEMALE WISTAR RATS

Abstract Resveratrol has antioxidant, anti-inflammatory, lipolytic, and antifibrotic properties, which may be useful in supplementation of obese patients and with liver problems. This study evaluated the effects of 6-week resveratrol supplementation on the lipid profile and liver function of female Wistar rats fed a high-fat diet to induce obesity. Sixty-four Wistar rats were divided into 4 groups (n = 16): the control group (C); the control obese group (CO); the resveratrol group (R); and the resveratrol obese group (RO). At the end of the experiment, the animals were anesthetized for blood collection and subsequent euthanasia for collection of liver biopsy. The parameters for body weight, liver weight, retroperitoneal fat weight, serum lipid and liver profiles and histopathological analysis were evaluated. The 6-week resveratrol administration did not induce weight loss nor did it reduce the lipid profile; however, it decreased the liver enzymes aspartate aminotransferase (AST) and alkaline phosphatase (ALP) and reduced the incidence of steatosis (75.0%) in group RO compared with group CO (81.2%). Thus, we concluded that resveratrol supplementation for the short period of six weeks had a beneficial effect on liver function by reducing hepatic steatosis and the liver enzymes AST and ALP in obese female rats.

CLÍNICA, ELETROCARDIOGRAFIA E ANÁLISE LABORATORIAL DE GATOS TRATADOS COM LEVAMISOL

O levamisol pode ser usado como parasiticida e indutor de imunidade. Na literatura há conflitos quanto à dose, vias de administração, efeitos adversos e toxicidade do fármaco em gatos. Com o objetivo de avaliar os efeitos clínicos, laboratoriais e eletrocardiográficos do levamisol em gatos, foram estudados nove animais, utilizando-se a dose imunomoduladora de 25 mg/gato, via oral, em dias alternados, por 3 aplicações (dias 1, 3 e 5). Os animais foram avaliados antes do levamisol (controle), 60, 180 e 360 minutos após administração do levamisol, em todos os dias de tratamento. Avaliou-se a temperatura (T), frequência respiratória (f), frequência cardíaca (FC), pressão arterial sistólica (PAS) e eletrocardiograma (ECG) em todos os momentos citados. Hemograma, função hepática, incluindo alanino aminotransferase (ALT) e gamaglutamil transferase (GGT), proteínas totais, albumina e globulinas foram avaliados antes e após a última aplicação do levamisol. Não foram observadas alterações da f, ALT, GGT e proteínas. A T, FC e PAS elevaram-se significativamente em diferentes momentos em relação ao controle, permanecendo, no entanto, dentro dos limites fisiológicos para a espécie. Sialorréia e vômito foram observados em 33,3% e 11,1% dos animais, respectivamente. No ECG foi observado bloqueio átrio-ventricular de 1º e 2º grau em 22,2% dos animais, nos dias 1 e 5, e complexos atriais prematuros em 33,3%, nos dias 1 e 3. No hemograma houve diminuição do número de linfócitos após a terceira dose administrada do fármaco. Conclui-se que na dose estudada o levamisol provoca efeitos tóxicos em gatos e deve ser usado com cautela.

New kidney immobilization method for percutaneous renal biopsy technique in cats. Operational aspects and complications

PURPOSE

Evaluate a new immobilization kidney method for collecting blind percutaneous renal biopsies (RB) in healthy cats.

METHODS

Ten cats were biopsied by a modified blinded percutaneous technique using semi-automated needles. Were evaluated the operational aspects of the technique, its complications, and the quality of the obtained samples. The evaluation included physical examination, hemogram, urinalysis, abdominal ultrasound, renal function, and histopathology of the biopsy specimens.

RESULTS

The developed technique was fast and easy to perform; it required two operators, and the right kidney was elected for specimen collection. After the RB, a decrease in hematocrit levels was observed in addition to hematuria and perirenal transient hematoma; however, no clinical consequences were observed, and normal parameters were restored within 48 hrs. There were no major complications or deaths, alterations in the physical examination or renal function, or signs of infection. Of the samples, 95% revealed the presence of renal tissue, and in 100% of the cats the samples were of diagnostic quality.

CONCLUSION

The technique was easily performed, provided adequate material for diagnosis with minimal transient complications.

Estudo comparativo da intoxicação experimental por amitraz entre cães e gatos

O objetivo do presente trabalho foi estudar as características em comum e as diferenças observadas na intoxicação induzida por 1 mg/kg de amitraz, IV, em cães e gatos. Os principais sinais clínicos observados em comum foram sedação, hipotermia, bradicardia, bradiarritmias, hipotensão, bradipnéia, midríase e hiperglicemia transitória, porém a intensidade destes sinais foi diferente entre as espécies. A hipotermia foi mais acentuada em gatos. Os cães foram mais sensíveis às alterações cardiorespiratórias apresentando diminuição mais significativa na freqüência cardíaca e respiratória, além de ocorrência de maior número de bradiarritmias. Os gatos apresentaram midríase mais prolongada do que os cães. Observou-se hiperglicemia e hipoinsulinemia transitórias e diminuição transitória dos níveis plasmáticos de cortisol em ambas espécies, porém os gatos apresentaram um pico de hiperglicemia maior e mais precoce do que os cães, e com relação aos níveis plasmáticos de cortisol, os cães apresentaram uma diminuição mais acentuada do que os gatos. O tempo médio de retorno da sedação foi mais prolongado em gatos. Estes resultados mostraram que a intoxicação por amitraz entre cães e gatos é muito similar, porém os gatos demonstraram maior sensibilidade à indução de hipotermia e hiperglicemia, além de midríase e um tempo médio de retorno da sedação mais prolongado, enquanto os cães apresentaram diminuição mais acentuada nos parâmetros cardiorespiratórios e dos níveis plasmáticos de cortisol do que os gatos.