Portal hypertension in dogs

Portal hypertension (PH) is the pathological increase in portal vein pressure above normal limits. Two variables control the pressure in the portal system: the resistance to blood flow and blood flow volume in the portal system. If one these variables changes, PH may develop. Classification: Pre-hepatic (e. g. compression of the portal vein), intrahepatic (e. g. chronic hepatitis and cirrhosis) or post-hepatic (e. g. right heart failure). The invasive methods (intravenous catheter) were replaced by an indirect method of diagnosis: Doppler Ultrasound. This technique does not measure portal pressure, but indirectly allows the diagnosis of PH. Average speed of portal flow decrease (<10 cm/s) and hepatofugal flow have been reported in cirrhotic dogs with PH. Currently, the focus of the ultrasound is the detection of acquired collateral portal circulation (ACPC), closely correlated with hepatic encephalopathy. The characterization of these vessels is essential to differentiate them from congenital shunts. They are usually multiple vessels, small and tortuous, with turbulent flow, near to the kidneys, and/or a single and larger vessel, draining into the left renal vein (dilated gonadal vein). Gastric, esophageal and mesenteric varices may occur. After identifying the PH, it is important to determine its origin in order to treat the underlying disease. B-Mode Ultrasound and Doppler are the best choices in cases of suspected PH, because they may recognize not just the hypertension, but also its complications and origin.

Data collection on bone density of mandibular alveolar bone on a Hounsfield scale of the dental apex of the cranial root of the first inferior molar in dogs using computed tomography at FMVZ-UNESP

The head is the most important and specialized region in the body because it contains a range of specialized organs and, because it has interconnections between specialized organs, there is a great overlap of images. Thus, computed tomography (CT) helps in diagnosing diseases in this region, such as oral conditions, as they provide millimetric slices or cuts and demonstrate the relationship between the various anatomical structures involved, in volume and depth. Within dentistry, CT helps in the identification of pathological processes such as infection, tumors, visualization of embedded teeth and bone bed. This study aimed to assess the density of the mandibular alveolar bone at a determined point to later predict how periodontal disease is involved in bone resorption. For this, we performed a blind retrospective study (n = 124) of the CT scan files of dog skulls at FMVZ-UNESP in order to determine the density of the jaw bone using a Hounsfield scale, in the region of the dental apex of the cranial root of the first molar tooth in dogs. The results obtained were evaluated using mean and standard deviation (27.28 +/- 9.53 HU) in order to predict the normal density of the mandibular alveolar bone in the studied region. Thus, this data analysis allows a more concise evaluation of bone resorption of mandibular alveolar bone and, therefore, provides an adequate surgical planning in cases of osteosynthesis given mainly by the presence of installed periodontal disease.

Iliac osteosynthesis with nylon clamp associated to polymethylmethacrylate bone cement - experimental study in dogs cadavers

Fractures of iliac body are generally consequences of traumas of great impact. These fractures lead to a lack of locomotor response and in specific cases, surgery is needed. Among the possible therapeutic lines, implants become a good option. In this paper, the authors used dog corpses to develop a surgery technique of iliac osteosynthesis, employing nylon clamps and bone cement of polymethylmethacrylate (PMMA). Sixteen hemi pelvises of eight dog corpses, which had its iliac bodies totally fractured previously, were utilized. The osteosynthesis was reached through the implantation of six nylon clamps, distributed equally between the bone fragments. With the use of the nylon clamps there were bone realignment and a contact surface to fixation of the biomaterial. The technique developed in corpses was easily executed, effective in reduction, alignment and stabilization of the fracture. The authors suggest more studies in vitro to evaluate immobilization resistance and functionality in dogs with this condition.

Molecular investigation of zoonotic genotypes of Giardia intestinalis isolates in humans, dogs and cats, sheep, goats and cattle in Araçatuba (Sãoo Paulo State, Brazil) by the analysis of beta-giardin gene fragments

In the period from July 2009 to October 2010, fecal samples from 61 animals and 154 humans from the municipality of Aracatuba (São Paulo State, Brazil) were studied. Fecal samples from animals were collected in the Municipal Animal Shelter and the Veterinary Hospital of the Universidade Estadual Paulista. Human fecal specimens were collected in playschools in the outskirts of the city by the private network of clinical analysis laboratories of the municipal. Diagnosis was done by optical microscopy using the Faust and Hoffmann, Pons and Janer techniques. The genotypes of Giardia intestinalis were characterized by PCR-RFLP and confirmed by sequencing the ß-giardin gene. Human specimens were positive in 25.3% (39/154) of the cases with 26.8% (36/134) of the specimens from children and 15% (3/20) from adults being positive. The frequency of G. intestinalis among the animals was 23.0% (14/61). A total of 32 isolates of G. intestinalis obtained from human feces and six from dogs and cats were characteristic of the A genotype (AI and AII/AIII). The results of this study in respect to frequency of giardiasis are similar to reported in most studies in Brazil. The prevalence observed in animal populations conforms to worldwide infection rates. G. intestinalis genotypes considered zoonotic were detected in both pets and humans from the city of Aractuba, suggesting a possible zoonotic transmission of the parasite in the northwestern region of São Paulo State. The absence of these genotypes in farm animals may imply that they are not involved in the chain of transmission to humans in this region.

Effect of platele-rich plasma on healing of class III furcation defects treated with autogenous bone grafting and guided tissue regeneration: a histomorphometric sutdy in dogs

Objective: The purpose of this study was to evaluate the effects of the platelet-rich plasma (PRP) when used in combination with autogenous bone graft and bioabsorbable membrane (Resolut® ) in the treatment of Class  III furcation defects in dogs. Material and method: Class III furcation defects (5 mm in height and in depth) were surgically created in the mandibular third premolars of five mongrel dogs. After nine weeks, the lesions were treated with scaling and root planning and each defect received one of the following treatments: autogenous bone graft + membrane (group C) or PRP + autogenous bone graft + membrane (group T). After a healing period of 90 days, the animals were sacrificed. Routine histological processing and staining with hematoxilyn and eosin and Masson trichrome were performed and a histomorphometric analysis determined the effect of the treatments on periodontal tissue regereneration. Data were analyzed by Hotelling’s T-squared (p < 0.05). Result: No statistically significant difference between C and T groups was observed by the histomorphometric analysis of the furcation area. Both treatment groups demonstrated similar regenerative results with the furcation defects partially filled and periodontal regeneration limited to the experimental notches of the lesions. (p > 0.05). Conclusion: According to the present results, PRP does not enhance the periodontal regeneration in class III furcation defects treated with autogenous bone graft and bioabsorbable membrane.

Deproteinized Bovine Bone Mineral or Autologous Bone at Dehiscence Type Defects at Implants Installed Immediately into Extraction Sockets: An Experimental Study in Dogs

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Connective tissue graft as a biological barrier for guided tissue regeneration in intrabony defects: a histological study in dogs

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of platelet-rich plasma on healing of class III furcation defects treated with autogenous bone grafting and guided tissue regeneration: a histomorphometric study in dogs

The purpose of this study was to evaluate the effects of the platelet-rich plasma (PRP) when used in combination with autogenous bone graft and bioabsorbable membrane (Resolut® ) in the treatment of Class  III furcation defects in dogs. Material and method: Class III furcation defects (5 mm in height and in depth) were surgically created in the mandibular third premolars of five mongrel dogs. After nine weeks, the lesions were treated with scaling and root planning and each defect received one of the following treatments: autogenous bone graft + membrane (group C) or PRP + autogenous bone graft + membrane (group T). After a healing period of 90 days, the animals were sacrificed. Routine histological processing and staining with hematoxilyn and eosin and Masson trichrome were performed and a histomorphometric analysis determined the effect of the treatments on periodontal tissue regereneration. Data were analyzed by Hotelling’s T-squared (p < 0.05). Result: No statistically significant difference between C and T groups was observed by the histomorphometric analysis of the furcation area. Both treatment groups demonstrated similar regenerative results with the furcation defects partially filled and periodontal regeneration limited to the experimental notches of the lesions. (p > 0.05). Conclusion: According to the present results, PRP does not enhance the periodontal regeneration in class III furcation defects treated with autogenous bone graft and bioabsorbable membrane.

Immunohistochemical evaluation of vascular endothelial growth factor (VEGF) in splenic hemangiomas and hemangiosarcomas in dogs

Formation of new blood vessels is paramount for tumour growth and metastatic dissemination and vascular endothelial growth factor (VEGF) is one of the key regulators of this process. The purpose of this study was to evaluate the immunohistochemical expression of VEGF in 23 splenic hemangiosarcomas and 7 splenic hemangiomas in dogs. Blood tests performed previous to splenectomy were analysed for correlation with tumour VEGF expression. Results showed significantly higher VEGF expression in hemangiosarcomas than hemangiomas and lower hematocrit values and red cell count in dogs affected with malignant neoplasia (P < 0.05). These findings suggest the presence of high VEGF levels may be related to the malignant vascular proliferation seen in hemangiosarcomas.

Capsular tension ring alone and associated with acrylic foldable intraocular lens in posterior capsular opacification after phacoemulsification in dogs

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Ophthalmic parameters in adult Shih Tzu dogs

Ocular surface diseases are often diagnosed in brachycephalic dogs. The ophthalmic parameters of the Shih Tzu dogs are evaluated in this study since this breed is among the most commonly affected by these diseases. In this study, ophthalmic parameters of this breed were partly studied under physical restraint. Schirmer tear test, breakup time test, aesthesiometry, biomicroscopy, non-contact specular microscopy, laser flaremetry, applanation tonometry, ultrasonography and ophthalmoscopy were carried in 48 eyes of 24 male and female dogs, aged from two to four years, weighing between 5 and 10kg. All dogs were from a breeding kennel. Descriptive statistics were applied to the data. Mean and standard error for Schirmer tear test was 26.145±0.803mm min-1; breakup time test, 13.668±0.538s; and aesthesiometry, 2.395±0.071cm. The biomicroscopy evaluation showed that 70.83% of the eyes had medial entropion; 42% caruncular trichiasis; 33% distichiasis, 27% mild paracentral corneal opacity; and 13% corneal melanosis. Mean and standard error for endothelial cell density was 2221.591±20.161cells mm-2; endothelial cell hexagonality, 63.770±1.805%; endothelial cell area, 451.895±4.179mm2; central corneal thickness, 0.490±0.007 mm; laser flaremetry, 1.720±0.216PC ms-1; applanation tonometry, 16.118±0.460mmHg; axial length, 20.255±0.134mm; lens thickness, 6.624±0.031mm; anterior chamber, 4.064±0.109mm; and vitreous chamber, 9.565±0.054mm. Ophthalmoscopy findings were not different from previous reports for other breeds. The results showed that the ophthalmic Shih Tzu parameters did not differ from other breeds according to data in the literature, except for the breakup time and Cochet-Bonnet aesthesiometry.

Bone marrow cytological evaluation in dogs with chronic kidneydisease

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Endodontics pastes formulated with copaiba oil: action on oral microbiota and dentin bridge formation in dogs

This study analysed the effect of pastes formulated with calcium hydroxide P.A. and different vehicles (saline solution - paste A and Copaifera langsdorffii Desfon oil - paste B) on oral microorganisms and dentin bridge formation in dogs. The antimicrobial action of the pastes and their components was analysed by the minimum inhibitory concentration in agar gel technique. The components were diluted and tested on fifteen standard strains of microorganisms associated with endodontic diseases. The microorganisms were cultivated and after incubation data was analysed using One-Way ANOVA and Turkey's test (P≤0.05). Four superior incisors of ten animals were used to evaluate dentin bridge formation. Two incisors were capped with paste A (GA) and two with paste B (GB). After 90 days, the teeth were extracted for histological analysis and the degree of dentin bridge formation evaluated. Data was analysed by the Kruskal-Wallis test (P<0.05). The pastes and their components were classified in the following decreasing order of antimicrobial action: calcium hydroxide P.A., paste A, paste B and Copaifera langsdorffii Desfon oil. Calcium hydroxide P.A. showed significantly higher antimicrobial action than the pastes or their vehicles. No significant difference was observed between the two pastes in dentin bridge formation. Based on the microorganisms studied, it can be concluded that the pastes analysed showed similar antimicrobial potential but differed significantly from their individual components. No significant difference was observed in dentin bridge formation between the different pastes tested.

Toxoplasmosis: morphological and morphometric evaluation of spinal cord neurons from nonsymptomatic seropositive dogs

The aim of this work was to analyze the neuron morphology and morphometry of cervical, thoracic and lumbar areas of nonsymptomatic seropositive dogs’ spinal cord for toxoplasmosis. Twenty indefinite-breed adult dogs were used; ten dogs were healthy, with negative serology for toxoplasmosis, and were used as the control group (group 1), and ten dogs were nonsymptomatic but seropositive for toxoplasmosis (group 2). After the microtomy, with interval of 100 micrometers (µm), the histological 5-µm-thick cuts were dyed by hematoxylin-eosin and Masson's trichrome techniques. The glass slides were analyzed under light microscope to examine the neuron morphology. The parameters considered for the morphometric analysis were area, perimeter, maximum diameter, minimum diameter and shape factor of cytoplasm and nucleus of neuron. The results were statistically analyzed by Student’s t test at 5% probability level. The morphological characteristics between the two groups were similar and according to literature. The morphometric results showed that there were changes in neurons size and structure, and increase and loss of star shape were noticed in seropositive animals. The results suggest that the neurons of these dogs, yet nonsymptomatic, can have lost their conductor function.

Hypertension and its correlation with renal lesions in dogs with leishmaniosis

To evaluate the prevalence of hypertension and its correlation with the severity of renal injury and proteinuria in dogs with leishmaniosis, sixty-six dogs were divided into two groups. Group 1 (G1) was composed of 54 dogs included in stage 1 of chronic kidney disease (CKD), and group 2 (G2) of twelve dogs in stages 2 and 3 of CKD. Prevalence of hypertension was 28.8%, comprising 22.2% of the dogs from G1 and 58.3% from G2 (P=0.011). The mean arterial blood pressure (BP) of dogs from G1 (135.7 +/- 20.5) was lower than from G2 (170.0 +/- 26.3) (P <0.001). Urine proteincreatinine ratio (UP/C) revealed values above 0.5 in 75.7% of the dogs, with 34% presenting hypertension. All dogs with hypertension had histopathological and laboratory evidence of glomerular disease. Although there was no statistically significant correlation between elevated BP and the severity of glomerular lesions (P=0.408), there was a statistically significant correlation between elevated BP and increased UP/C in the studied population (P=0.002). Thus, dogs with leishmaniosis and renal disease must be screened for the presence of hypertension so that treatment may be instituted as early as possible, in countries where treatment is allowed, to prevent the progression of renal damage.