Diagnosis, Prognosis, and Treatment of Canine Hemangiosarcoma: A Review Based on a Consensus Organized by the Brazilian Association of Veterinary Oncology, ABROVET.

Hemangiosarcoma is a mesenchymal neoplasm originating in the endothelial cells of blood vessels; they can be classified as non-visceral and visceral types. Non-visceral hemangiosarcomas can affect the skin, subcutaneous tissues, and muscle tissues; visceral hemangiosarcomas can affect the spleen, liver, heart, lungs, kidneys, oral cavity, bones, bladder, uterus, tongue, and retroperitoneum. Among domestic species, dogs are most affected by cutaneous HSA. Cutaneous HSA represents approximately 14% of all HSA diagnosed in this species and less than 5% of dermal tumors, according to North American studies. However, Brazilian epidemiological data demonstrate a higher prevalence, which may represent 27 to 80% of all canine HSAs and 13.9% of all skin neoplasms diagnosed in this species. Cutaneous HSA most commonly affects middle-aged to elderly dogs (between 8 and 15 years old), with no gender predisposition for either the actinic or non-actinic forms. The higher prevalence of cutaneous HSA in some canine breeds is related to lower protection from solar radiation, as low skin pigmentation and hair coverage lead to greater sun exposure. Actinic changes, such as solar dermatosis, are frequent in these patients, confirming the influence of solar radiation on the development of this neoplasm. There are multiple clinical manifestations of hemangiosarcoma in canines. The diagnostic approach and staging classification of cutaneous HSAs are similar between the different subtypes. The definitive diagnosis is obtained through histopathological analysis of incisional or excisional biopsies. Cytology can be used as a presurgical screening test; however, it has little diagnostic utility in cases of HSA because there is a high risk of blood contamination and sample hemodilution. Surgery is generally the treatment of choice for dogs with localized non-visceral HSA without evidence of metastatic disease. Recently, electrochemotherapy (ECT) has emerged as an alternative therapy for the local ablative treatment of different neoplastic types; the use of radiotherapy for the treatment of dogs with cutaneous HSA is uncommon. There is greater consensus in the literature regarding the indications for adjuvant chemotherapy in subcutaneous and muscular HSA; doxorubicin is the most frequently used antineoplastic agent for subcutaneous and muscular subtypes and can be administered alone or in combination with other drugs. Other therapies include antiangiogenic therapy, photodynamic therapy, the association of chemotherapy with the metronomic dose, targeted therapies, and natural products. The benefits of these therapies are presented and discussed. In general, the prognosis of splenic and cardiac HSA is unfavorable. As a challenging neoplasm, studies of new protocols and treatment modalities are necessary to control this aggressive disease.

Eleven-year retrospective analysis of acquired diaphragmatic hernia in 49 dogs and 48 cats.

Data on dogs and cats that underwent surgery for a traumatic diaphragmatic hernia were retrospectively collected and analyzed, with an objective to identify factors that influenced the survival rate. Forty-nine dogs and 48 cats were included. The predominant respiratory clinical sign was dyspnea, and the interval from trauma to development of clinical signs did not influence patient survival. Concurrent orthopedic and/or soft tissue injuries were identified in 48.45% of the animals. Intraoperative complications occurred in 14 dogs and 5 cats, and postoperative complications in 7 dogs and 6 cats. Intraoperative death occurred in 6.2% and postoperative death in 8.3% from 1 h to 10 d after surgery. Animals that received surgical treatment within 48 h after diagnosis had a lower risk of death. Conversely, concurrent injuries and intraoperative and postoperative complications were the main factors associated with a higher risk of death.

Analyse rétrospective sur onze ans des hernies diaphragmatiques acquises chez 49 chiens et 48 chats. Les données sur les chiens et les chats ayant subi une intervention chirurgicale pour une hernie diaphragmatique traumatique ont été recueillies et analysées rétrospectivement, dans le but d'identifier les facteurs qui ont influencé le taux de survie. Quarante-neuf chiens et 48 chats ont été inclus. Le signe clinique respiratoire prédominant était la dyspnée, et l'intervalle entre le traumatisme et le développement des signes cliniques n'a pas influencé la survie des patients. Des lésions orthopédiques et/ou des tissus mous concomitantes ont été identifiées chez 48,45 % des animaux. Des complications peropératoires sont survenues chez 14 chiens et cinq chats, et des complications postopératoires chez sept chiens et six chats. Le décès peropératoire est survenu chez 6,2 % et le décès postopératoire chez 8,3 % de 1 h à 10 j après la chirurgie. Les animaux qui ont reçu un traitement chirurgical dans les 48 h après le diagnostic avaient un risque de décès plus faible. À l'inverse, les blessures concomitantes et les complications peropératoires et postopératoires étaient les principaux facteurs associés à un risque de décès plus élevé.(Traduit par Dr Serge Messier).

Caveolin-1, GATA-3, and Ki67 expressions and their correlation with pathological findings in canine bladder urothelial carcinoma.

The bladder urothelial carcinoma (UC) represents ~2% of malignant neoplasms in dogs and is a therapeutic challenge in veterinary medicine. Although it is considered the most common bladder cancer in dogs, few previous studies have investigated different markers that correlate with clinical and pathological parameters. Therefore, this study aimed to evaluate Caveolin-1, GATA-3, and Ki67 immunostaining in canine UC samples to evaluate their correlations with histopathological variables. Thirty tumor samples were obtained, and Caveolin-1, GATA-3, and Ki67 expression was assessed by immunohistochemistry and associated with pathological factors by univariate and multivariate analyses. Among the histopathological findings, lymphatic invasion was identified in 53.33% of the tumors, and the mean mitotic count (MC) was 31.82 ± 26.26. Caveolin-1 showed mild-to-high cytoplasmic expression in neoplastic cells, whereas GATA-3 showed mild-to-high nuclear expression. The Ki67 expression revealed a mean of 24.14 ± 16.88% positive cells. In the univariate analysis, no association was found between each marker and the pathological findings. On the other hand, in multivariate analysis, we identified a positive correlation between GATA-3 and MC and a negative correlation between Caveolin-1 and MC. Moreover, lymphatic invasion was positively correlated with histological type and grade, and negatively correlated with MC. In addition, the histological type was positively correlated with the histological grade. Overall, our results indicate that Caveolin-1 and GATA-3 expression could be promising markers for bladder UC aggressiveness.

Fasting and 24-h urine pH in patients with urolithiasis using potassium citrate.

PURPOSE: To evaluate the correlation between the pH readings in 24-h urine and the random fasting specimen in patients with urolithiasis using 2 methods. METHODS: A total of 114 patients with urinary lithiasis using potassium citrate were prospectively analyzed. All patients collected 24-h urine and an additional sample, after nocturnal fasting, collected on the day they brought the 24-h sample at the lab. Two different methods (test strip and digital meter) were used to determine pH values. RESULTS: The pH analysis using strips in the 24-h urine presented a mean value similar to the one obtained in the fasting sample (6.07 ± 0.74 vs. 6.02 ± 0.82, respectively; P > 0.05). The same behavior was seen considering the readings with a digital pH meter (5.8 ± 0.78 vs. 5.75 ± 0.83; P > 0.05). However, readings conducted in the same specimen with pH meter and test strip were dissonant (P < 0.05), suggesting that the colorimetric method is not reliable in the assessment of urinary pH in this population. CONCLUSION: pH assessment in a random urinary specimen proved as efficient as the 24-h urine standard method to monitor patients with kidney stones in the use of potassium citrate. Classical test strip analysis is not sensitive enough to evaluate the urine pH in this population and digital pH meter reading is preferred.

Influence of staple line number and configuration on the leakage of small intestinal functional end-to-end stapled anastomosis: An ex vivo study.

OBJECTIVE: To determine the influence of the staple line configuration on the leakage of small intestinal functional end-to-end stapled anastomosis (FEESA). STUDY DESIGN: Experimental, ex vivo, randomized study. SAMPLE POPULATION: Jejunal segments (N = 72) from 10 mature, canine cadavers. METHODS: Jejunal segments (10 cm) were randomly assigned to a control group (8 segments) and 4 FEESA groups (16 segments/group (8 constructs/group)), according to the number of rows of staples used in the vertical (V) and transverse lines (T), respectively: Control, 2-row V/2-row T (2V/2T), 2-row V/3-row T (2V/3T), 3-row V/2-row T (3V/2T), 3-row V/3-row T (3V/3T). Initial leak pressure (ILP), maximum intraluminal pressure (MIP), and initial leakage location (ILL) were compared. RESULTS: The ILP (mean ± SD) for control segments, 2V/2T, 2V/3T, 3V/2T and 3V/3T were 321.38 ± 34.59, 32.88 ± 7.36, 50.13 ± 10.46, 34.38 ± 11.78, 69.88 ± 21.23 mmHg, respectively. All FEESAs initially leaked at lower pressures than intact segments. The only other differences detected between groups consisted of ILPs that were higher when FEESAs were closed with 3V/3T (69.88 ± 21.23 mmHg) than 2V/2T (32.88 ± 7.36, P < .001). Initial leakage occurred predominantly from the transverse staple line rather than the anastomotic crotch (P < .001). CONCLUSION: Placing 3 rows of staples in the transverse line (with or without a third row in the vertical staple line) improved resistance to leakage of FEESAs in normal cadaveric specimens. CLINICAL SIGNIFICANCE: The addition of a third row of staples in the transverse line (with or without a third row in the vertical staple line) in FEESAs should be further investigated as a strategy to reduce intestinal leakage clinically.

Angularis oris axial pattern flap as a reliable and versatile option for rostral facial reconstruction in cats.

OBJECTIVE: To evaluate outcomes associated with the use of an angularis oris axial pattern flap (AOAPF) for rostral facial reconstruction in cats. ANIMALS: Nine adult client-owned cats. STUDY DESIGN: Short case series. METHODS: Ten AOAPF were performed in nine cats after resection of a tumor. Wounds were located at the nose, infraorbital, supraorbital, frontal, eye, and ear canal region. Orbital exenteration (n = 3), pinnectomy (n = 2), nasal planum resection, total ear canal ablation (n = 2), and partial eyelid reconstruction (n = 3) were performed. RESULTS: Short-term postoperative complications included flap edema (n = 10), suture dehiscence (n = 3), and distal tip necrosis (n = 3). All wounds resulting from minor complications healed by second intention in 5-15 days. Long-term complications included epiphora (n = 2), frequent grooming around the eyes (n = 2), and enucleation due to corneal ulcer secondary to impaired postoperative eyelid function (n = 1). Tumor recurrence occurred in 3 cases. CONCLUSION: The AOAPF was a versatile and reliable option for rostral facial reconstruction in cats with acceptable long-term outcomes.

Lymphatic invasion is a significant indicator of poor patient outcome in canine bladder urothelial carcinoma.

BACKGROUND: Urothelial carcinoma (UC), also known as transitional cell carcinoma, is the most common malignant tumor of the canine urinary bladder and represents a model for studying human bladder cancer. However, the existing literature has limited data on the clinicopathological characteristics of these tumors and their prognostic value. AIM: The aim of this study was to evaluate such factors, correlating them with follow-up, in a group of 32 dogs with bladder UC. METHODS: Clinical data of these cases, submitted to São Paulo State University and VetPat Private Laboratory (São Paulo/Brazil), were recorded between January 2000 and November 2019. For each case, formalin-fixed and paraffin-embedded sections were stained with hematoxylin and eosin and histologically evaluated. Survival analysis was carried out, and the prognostic value of the presence of lymphatic invasion and the treatment used was determined. RESULTS: Dogs with neoplastic lymphatic vessel invasion had a lower overall survival compared to those without lymphatic invasion, and dogs that received vinblastine in addition to surgery had higher global survival when compared to animals that received carboplatin in addition to surgery. CONCLUSION: The results obtained show the importance of further studies regarding the prognostic value of the two factors demonstrated as potential survival predictors, especially the lymphatic vessel invasion.

Evaluation of the performance of an endoscopic 3-mm electrothermal bipolar vessel sealing device intended for single use after multiple use-and-resterilization cycles.

OBJECTIVE: To evaluate the performance of an endoscopic 3-mm electrothermal bipolar vessel sealing device (EBVS) intended for single use after multiple use-and-resterilization cycles. STUDY DESIGN: Ex vivo study. SAMPLE POPULATION: Eight 3-mm EBVS handpieces. METHODS: Handpieces were subjected to a maximum of 15 cycles of testing, including simulated surgery, sealing and burst pressure testing of porcine carotid arteries, reprocessing, and hydrogen peroxide plasma resterilization. Failure was defined as two sequential vascular seal leakage events occurring at <250 mm Hg. Histological evaluation, maximum external temperature of the jaws, sealing time, tissue adherence, jaw surface characterization, and mechanical deterioration were studied. Failure rate was analyzed by using a Kaplan-Meier curve. Linear and ordinal logistic mixed models were used to analyze sealing time, handpiece jaw temperature, and adherence score. RESULTS: Mean ± SD diameter of arteries was 3.22 ± 0.35 mm. Failure was observed starting at cycle 10 and going up to cycle 13 in 37.5% (3/8) of the handpieces. Tissue adherence increased after each cycle (P < .001). Maximum external temperature (79.8°C ± 13.9°C) and sealing time (1.8 ± 0.5 seconds) were not significantly different throughout cycles up to failure. A flatter surface and large scratches were observed microscopically throughout the jaw surface after repeated use and resterilization. CONCLUSION: The 3-mm EBVS handpiece evaluated in this study can be considered safe to use for up to nine reuse-and-resterilization cycles. CLINICAL SIGNIFICANCE: These data provide the basis for establishing preliminary guidelines for the reuse and hydrogen peroxide plasma resterilization of an endoscopic 3-mm EBVS handpiece.

Effects of pneumoperitoneum and of an alveolar recruitment maneuver followed by positive end-expiratory pressure on cardiopulmonary function in sheep anesthetized with isoflurane-fentanyl.

OBJECTIVE: To investigate the effects of pneumoperitoneum alone or combined with an alveolar recruitment maneuver (ARM) followed by positive end-expiratory pressure (PEEP) on cardiopulmonary function in sheep. STUDY DESIGN: Prospective, randomized, crossover study. ANIMALS: A total of nine adult sheep (36-52 kg). METHODS: Sheep were administered three treatments (≥10-day intervals) during isoflurane-fentanyl anesthesia and volume-controlled ventilation (tidal volume: 12 mL kg-1) with oxygen: CONTROL (no intervention); PNEUMO (120 minutes of CO2 pneumoperitoneum); PNEUMOARM/PEEP (PNEUMO protocol with an ARM instituted after 60 minutes of pneumoperitoneum). The ARM (5 cmH2O increases in PEEP of 1 minute duration until 20 cmH2O of PEEP) was followed by 10 cmH2O of PEEP until the end of anesthesia. Cardiopulmonary data were recorded until 30 minutes after abdominal deflation. RESULTS: PaO2 was decreased from 435-462 mmHg (58.0-61.6 kPa) (range of mean values in CONTROL) to 377-397 mmHg (50.3-52.9 kPa) in PNEUMO (p < 0.05). Quasistatic compliance (Cqst, mL cmH2O-1 kg-1) was decreased from 0.85-0.92 in CONTROL to 0.52-0.58 in PNEUMO. PaO2 increased from 383-385 mmHg (51.1-51.3 kPa) in PNEUMO to 429-444 mmHg (57.2-59.2 kPa) in PNEUMOARM/PEEP (p < 0.05) and Cqst increased from 0.52-0.53 in PNEUMO to 0.70-0.74 in PNEUMOARM/PEEP. Abdominal deflation in PNEUMO did not restore PaO2 and Cqst to control values. Cardiac index (L minute-1 m2) decreased from 4.80-4.70 in CONTROL to 3.45-3.74 in PNEUMO and 3.63-3.76 in PNEUMOARM/PEEP. Compared with controls, ARM/PEEP with pneumoperitoneum decreased mean arterial pressure from 81 to 68 mmHg and increased mean pulmonary artery pressure from 10 to 16 mmHg. CONCLUSIONS AND CLINICAL RELEVANCE: Abdominal deflation did not reverse the pulmonary function impairment associated with pneumoperitoneum. The ARM/PEEP improved respiratory compliance and reversed the oxygenation impairment induced by pneumoperitoneum with acceptable hemodynamic changes in healthy sheep.

Histological, morphometric, protein and gene expression analyses of rat retinas with ischaemia-reperfusion injury model treated with sildenafil citrate.

The aim of this study was to better understand the role of apoptosis in a retinal ischaemia-reperfusion injury model and to determine whether sildenafil citrate treatment can prevent retinal cell apoptosis. Thirty-six rats were divided into a control group (n = 6) and two experimentally induced ischaemia-reperfusion groups (7 and 21 days; n = 15 per group). The induced ischaemia-reperfusion groups were treated with sildenafil for 7 and 21 days (n = 10 per group), and 10 animals were treated with a placebo for the same period (n = 5 per group). Paracentesis of the anterior chamber was performed with a 30-G needle attached to a saline solution (0.9%) bag positioned at a height of 150 cm above the eye for 60 min. Intraocular pressure was measured by rebound tonometer (TonoVet® ). The eyes were analysed by histology and morphometry, and by immunohistochemistry and qRT-PCR for expression of Caspase-7, Caspase-6, Caspase-9, Tnf-r2, Fas-l, Bcl-2 and Bax. Sildenafil-treated animals showed lower levels of histopathological changes (inflammatory, cellular and tissue) than their placebo-treated counterparts at both 7 and 21 days. The retinal ganglion cell layer (RGC) was preserved in the sildenafil groups (SG), with a cell count closer to control than in the placebo groups (PG). Caspase-7 expression was significantly higher in both treated groups at 7 days compared to controls. Gene expression levels in both treatment groups differed from the controls, but in SG Bax and Caspase-6 expression levels were similar to control animals. These results suggest that the main mechanism of retinal cell death in this model is apoptosis, as there is an increase in pro-apoptotic factors and decrease in the anti-apoptotic ones. Also, sildenafil seems to protect the retinal ganglion cell layer from apoptosis. Cell survival was evident in the histological and morphometric analyses, and sildenafil treatment had a protective effect in the apoptosis pathways, with gene expression levels in SG similar to the controls.

Eficácia da ciclosporina no controle da dermatite atópica em cães / Efficacy of cyclosporine in the control of atopic dermatitis in dogs

A dermatite atópica é uma dermatopatia inflamatória, pruriginosa, crônica, de origem genética, resultante da perda da função de barreira física da pele e da hiperreatividade à alérgenos ambientais, trofoalérgenos, alérgenos microbianos e a irritantes primários. Este estudo avaliou a eficácia da ciclosporina no controle do prurido e das lesões associadas à dermatite atópica em cães. Selecionaram-se 24 cães com diagnóstico de dermatite atópica baseados nos critérios de Favrot et al. (2010), os quais foram divididos em dois grupos de 12 cães, onde o Grupo 1, recebeu ciclosporina (5mg/kg/vo/24h), e o Grupo 2, foi tratado com prednisona (0,5mg/kg/vo/24h) em doses decrescentes, ambos por 60 dias. Os animais foram continuamente avaliados, e seus escores sintomato-lesionais, baseados na escala de CADESI-03, estabelecidos nos dias 0, 30 e 60. Em adição, os escores de prurido de cada animal, baseado nos critérios de Rybnicek, foram semanalmente avaliados, do dia 0 ao 63. Todos os dados coletados foram analisados pelo teste não paramétrico de Kruskal-Wallis, seguido do teste de Dunn´s e para as análises entre os grupos foi utilizado o teste t, considerado o nível de significância mínimo de 5%. A ciclosporina teve uma eficácia similar, no controle lesional, ao grupo que recebeu prednisona no dia (+30) (p<0,05) e no dia (+60) (p<0,001) do tratamento, em relação ao dia zero. Uma diferença significativa do escore do prurido foi observada nos dias +28, +35, +42, +49, +56 e +63 (p<0,001), e no dia +21 (p<0,01) em relação ao momento inicial do tratamento, porém sua eficácia foi inferior ao Grupo 2, a partir do 42º dia de avaliação, mantendo-se esta diferença nos dias +49, +56 e +63 (p>0,05). Apesar da ciclosporina ter sido menos eficaz no controle do prurido, este se manteve em níveis aceitáveis, e seu uso contínuo não foi associado a efeitos colaterais relevantes.(AU)

Atopic dermatitis is an itchy, chronic inflammatory skin disease of genetic origin, resulting from loss of the physical barrier function of the skin and hyper-reactivity to environmental allergens, trofoallergens, microbial allergens and to primary irritants. The efficacy of cyclosporine in the control of pruritus and lesions associated with atopic dermatitis in dogs was evaluated. Twenty-four dogs with atopic dermatitis were selected, based on Favrot et al.'s criteria (2010). They were divided into two groups of 12 dogs, where Group 1 received cyclosporine (5mg/kg/vo/24h), and Group 2 was treated with prednisone (0.5mg/kg/vo/24h) in decreasing doses, both for 60 days. The animals were continuously evaluated, and theirits lesional symptomatology scores were based on a Cadesi-03 scale, set on days 0, 30 and 60. Pruritus scores of each dog, based on Rybnicek´s criteria, were weekly evaluated, from day 0 to day 63. All collected data were analyzed by the nonparametric Kruskal-Wallis´ test, followed by Dunn's test, and for the analysis between the groups, considered the minimum significance level of 5%, t-test was used. Cyclosporin had similar efficacy in lesional control in the group which received prednisone on day (+30) (p<0.05) and on the day (+60) (p<0.001) of treatment, compared with day zero. A significant difference of the itching score was observed on days +28, +35, +42, +49, +56 and +63 (p<0.001), and on day +21 (p<0.01) when compared to initial treatment. However, its efficacy was lower than Group 2, from 42 days of evaluation on, keeping such difference on days +49, +56 and +63 (p>0.05). Although cyclosporin have been less effective in controlling itching, it remained at acceptable levels, and its continued use was not associated with significant side effects.(AU)

Can a graft be placed over a flap in complex hypospadias surgery? An experimental study in rabbits

ABSTRACT Purpose: To develop a rabbit experimental study to test the hypothesis that surgical repair of hypospadias with severe ventral curvatures might be completed in one stage, if a graft, such as buccal mucosa, could be placed over the tunica vaginalis flap used in corporoplasty for ventral lengthening, with the addition of an onlay preputial island flap to complete the urethroplasty. Materials and methods: The experimental procedure with rabbits included a tunica vaginalis flap for reconstruction of the corpora after corporotomy, simulating a ventral lengthening operation. A buccal mucosa graft was placed directly on top of the flap, and the urethroplasty was completed with an onlay preputial island flap. Eight rabbits were divided into 4 groups, sacrificed at 2, 4, 8 and 12 weeks postoperatively, and submitted to histological evaluation. Results: We observed a large number of complications, such as fistula (75%), urinary retention (50%) and stenosis (50%). There were two deaths related to the procedure. Histological evaluation demonstrated a severe and persistent inflammatory reaction. No viable tunica vaginalis or buccal mucosa was identified. Conclusions: In this animal model, the association of a buccal mucosa graft over the tunica vaginalis flap was not successful, and resulted in complete loss of both tissues.

Can a graft be placed over a flap in complex hypospadias surgery? An experimental study in rabbits.

PURPOSE: To develop a rabbit experimental study to test the hypothesis that surgical repair of hypospadias with severe ventral curvatures might be completed in one stage, if a graft, such as buccal mucosa, could be placed over the tunica vaginalis flap used in corporoplasty for ventral lengthening, with the addition of an onlay preputial island. flap to complete the urethroplasty. MATERIALS AND METHODS: The experimental procedure with rabbits included a tunica vaginalis flap for reconstruction of the corpora after corporotomy, simulating a ventral lengthening operation. A buccal mucosa graft was placed directly on top of the flap, and the urethroplasty was completed with an onlay preputial island flap. Eight rabbits were divided into 4 groups, sacrificed at 2, 4, 8 and 12 weeks postoperatively, and submitted to histological evaluation. RESULTS: We observed a large number of complications, such as fistula (75%), urinary retention (50%) and stenosis (50%). There were two deaths related to the procedure. Histological evaluation demonstrated a severe and persistent inflammatory reaction. No viable tunica vaginalis or buccal mucosa was identified. CONCLUSIONS: In this animal model, the association of a buccal mucosa graft over the tunica vaginalis flap was not successful, and resulted in complete loss of both tissues.

Placas ósseas confeccionadas a partir de diáfise cortical equina na osteossíntese femoral em coelhos / Bone plates produced from equine cortical bone in rabbits femoral osteosynthesis

A evolução tecnológica tem possibilitado o desenvolvimento e o aperfeiçoamento de novos materiais para implantes. Apesar dos fundamentais benefícios providos pelos dispositivos ortopédicos, complicações decorrentes de corrosão, degradação, infecção, além de outras podem ocorrer. O entendimento das características dos biomateriais é fundamental para a previsibilidade do seu comportamento in vivo, fornecendo subsídios para que o composto mais adequado seja escolhido na reconstrução do defeito ósseo. As placas de origem metálica são as mais utilizadas para o reparo de fraturas de ossos longos, sendo mecanicamente resistentes e biocompatíveis. No entanto, a necessidade de remoção e o enfraquecimento do osso são suas principais desvantagens. Neste trabalho, placas produzidas a partir de osso cortical equino foram empregadas experimentalmente em fêmur osteotomizado de coelhos (Grupo osso-GO), num estudo comparativo com placas de metal (Grupo metal-GM). A avaliação radiográfica foi realizada a cada 30 dias, durante 120 dias, momento em que foi então realizada análise histológica do material em estudo. Não houve diferença estatisticamente significante entre os dois grupos com relação à morfometria do calo ósseo e consolidação óssea em todos os momentos avaliados, sendo que ambas as placas permitiram a consolidação em todos os animais. Entretanto, observou-se que o calo ósseo foi menor no GO, em relação ao GM, em todos os momentos do estudo. Por outro lado, a maior parte dos animais do GO apresentou consolidação completa da fratura aos 90 dias, enquanto que no GM isto ocorreu aos 60 dias. Não foram evidenciadas células do tipo corpo estranho na histopatologia dos animais do GO, mas maior quantidade de tecido fibroso foi identificada, envolvendo este biomaterial. A placa confeccionada com osso equino representa uma alternativa de baixo custo e muito viável, uma vez que permitiu estabilização adequada para consolidação óssea de fratura de fêmur em ...

Actually, technological advances have contributed to the development and improvement of new materials for implants. Despite the fundamental benefits provided by orthopedic materials, complications resulting from corrosion, degradation, infection, and others may occur. The knowledge of characteristics of the biomaterials is important to predict their behavior in vivo, supporting that the most suitable compound is chosen to reconstruct the bone defect. Metallic plates are the most common material used for repair of long bone fractures, and they are mechanically stable and biocompatible. However, the need of removal and bone weakening are their disadvantages. In this paper, plates made from equine cortical bone were used experimentally in osteotomized rabbit femur (bone-GO Group), in a comparative study with metal plates (metal GM Group). Radiographic evaluation was performed every 30 days during 120 days, at which time was then performed femur histological analysis. During all evaluated moments of the study, there was no statistically significant difference between the two groups in callus morphometry, and complete consolidation was observed in all animals. However, it was observed that the callus was lower in GO compared to GM, all times during the study. Moreover, most of the GO animals showed complete consolidation fracture at 90 days only, whereas this occurred in GM at 60 days. There were no foreign-body cells in the histopathology exam of the GO animals, but larger amount of fibrous tissue was identified, involving this biomaterial. The plate made from horse bone represents a low cost alternative and it is very feasible, it allowed adequate stabilization of femur fracture in rabbits. In this study, the lower periosteal callus associated with a longer time for consolidation in GO suggest greater fracture stability when the bone plate was used.

Comparative study between porcine small intestinal submucosa and buccal mucosa in a partial urethra substitution in rabbits.

PURPOSE: Several urethral conditions may require tissue substitution. One collagen-base biomaterial that recently emerged as an option is small intestinal submucosa (SIS). The aim of this study was to compare the results of SIS and buccal mucosa for urethral substitution in rabbits. MATERIALS AND METHODS: Thirty-six North Folk male rabbits were randomized into three groups. In all animals, a 10 × 5 mm urethral segment was excised, and the urethral defect was repaired using a one-layer SIS patch (group I [GI]); four-layer SIS (group II [GII]); or buccal mucosa (group III [GIII]). Urethrography was performed preoperatively and after 12 weeks. After sacrifice, graft retraction was objectively measured using Scion Image(®) computer analysis and by calculation of ellipse area. The grade of fibrosis, inflammatory reaction, vascular/epithelial regeneration, and collagen III/I ratio were analyzed by hematoxylin/eosin and Picrosirius red staining. RESULTS: Urethrography confirmed a wide urethral caliber without any signs of strictures after surgery. Urethral fistulae was diagnosed in 8.3% of cases (1 animal each group). Average graft shrinkage was 55.2% in GI; 44.2% in GII; and 57.2% in GIII (p<0.05). The intensity of chronic inflammation, fibrosis, epithelium regeneration, and neovascularization was similar in all groups (p>0.05). Collagen III/I ratio was higher in GII (GI: 119.6; GII: 257.2 and GIII: 115.0); p<0.01. CONCLUSIONS: The four-layer SIS is more advantageous than the one-layer SIS and buccal mucosa for urethral substitution in rabbits.

Cold renal ischemia: comparison of efficacy between two techniques of cooling, in a swine model.

OBJECTIVES: In a swine model of renal ischemia, we compared the effectiveness of the transurethral retrograde cold saline perfusion technique to the traditional method of renal cooling with ice slush, in achieving adequate parenchymal temperatures for functional preservation of the organ. Physiological and histological effects were also assessed. METHODS: Twenty-four domestic male pigs were sampled into four groups to be submitted to a 60-minute ischemia of the left kidney without cooling, with either one of the two cooling techniques (cold saline retrograde perfusion or ice slush), or sham surgery. All of them had also a concomitant right nephrectomy. Renal cortical and medullary temperatures were recorded throughout the experiment. Urinary output was measured, and serum renal function tests were carried on, pre- and postoperatively. After 5 days, the animals were euthanized and their kidneys were submitted to histological analysis. RESULTS: Mean renal temperature fell in both groups submitted to kidney cooling. With ice slush, a faster drop was observed and a lower minimum temperature was achieved (5.0 degrees C in the cortex and 6.3 degrees C in the medulla, vs. 25.4 degrees C and 24.9 degrees C with retrograde cooling). In the other groups, temperature was unchanged. Urinary output and serum creatinine worsened after the experiment, but without significant differences among groups. The histological analysis showed no differences among the four groups, for the studied ischemia time. CONCLUSIONS: Ice slush and retrograde perfusion of cold saline are both effective for cooling the kidney during ischemia. Ice slush is faster in doing so, and it allows much lower temperatures to be achieved in the renal parenchyma. With ischemia time of 60 minutes, no significant differences on the occurrence of functional and histological alterations were detected, even for the group without a cooling procedure.

Paraganglioma de corpo aórtico e carotídeo / Aortic and carotid body paraganglioma / Paraganglioma de cuerpo aórtico y carótida

Os paragangliomas são neoplasias de células neuroendócrinas (Paraneurônios) do sistema parassimpático (Paraganglia), e ocorrem normalmente no corpo aórtico (base do coração) e carotídeo (pescoço). São tumores raros, frequentemente benignos, que podem raramente metastatizar. Raças braquiocefálicas e animais que vivem em elevadas altitudes são mais predispostos ao desenvolvimento de paragangliomas. Esta revisão bibliográfica objetiva-se descrever as manifestações clínicas, etiopatogenia, formas de diagnóstico e tratamento dos paragangliomas.

The paraganglioms are neoplasms of neuroendocrine cells (Paraneurons) of the parasympathetic system (Paraganglia). Normally occur on the aortic (base of heart) and carotid (neck) bodies. They are rare tumors, frequently beginners and its rarely able to metastasize. Braquicephalics breeds and animals that live in high altitudes are more predisposed to developing paraganglioms. This bibliographic review describes clinical manifestation, etiopathogeny and types of diagnosis and treatment of the paraganglioms.

Los paragangliomas son neoplasias de las células neuroendocrinas (Paraneuronas) del sistema parasimpático (Paraganglios) y ocurren normalmente en el cuerpo aórtico (base del corazón) y carótida (cuello). Son tumores raros, frecuentemente benignos, que pueden raramente ocurrir metástasis. Razas braquiocefálicas y animales que viven en altas altitudes son más predispuestos al desenvolvimiento de paragangliomas. Esta revisión bibliográfica describe las manifestaciones clínicas, etiopatogenia, método de diagnóstico y tratamiento de los paragangliomas.

Comparative study on the sedative effects of morphine, methadone, butorphanol or tramadol, in combination with acepromazine, in dogs.

OBJECTIVE: To compare the effects of morphine (MOR), methadone (MET), butorphanol (BUT) and tramadol (TRA), in combination with acepromazine, on sedation, cardiorespiratory variables, body temperature and incidence of emesis in dogs. STUDY DESIGN: Prospective randomized, blinded, experimental trial. ANIMALS: Six adult mixed-breed male dogs weighing 12.0 +/- 4.3 kg. METHODS: Dogs received intravenous administration (IV) of acepromazine (0.05 mg kg(-1)) and 15 minutes later, one of four opioids was randomly administered IV in a cross-over design, with at least 1-week intervals. Dogs then received MOR 0.5 mg kg(-1); MET 0.5 mg kg(-1); BUT 0.15 mg kg(-1); or TRA 2.0 mg kg(-1). Indirect systolic arterial pressure (SAP), heart rate (HR), respiratory rate (f(R)), rectal temperature, pedal withdrawal reflex and sedation were evaluated at regular intervals for 90 minutes. RESULTS: Acepromazine administration decreased SAP, HR and temperature and produced mild sedation. All opioids further decreased temperature and MOR, BUT and TRA were associated with further decreases in HR. Tramadol decreased SAP whereas BUT decreased f(R) compared with values before opioid administration. Retching was observed in five of six dogs and vomiting occurred in one dog in MOR, but not in any dog in the remaining treatments. Sedation scores were greater in MET followed by MOR and BUT. Tramadol was associated with minor changes in sedation produced by acepromazine alone. CONCLUSIONS AND CLINICAL RELEVANCE: When used with acepromazine, MET appears to provide better sedation than MOR, BUT and TRA. If vomiting is to be avoided, MET, BUT and TRA may be better options than MOR.

Efeitos sedativo e cardiorrespiratório da administração da metadona, isoladamente ou em associação à acepromazina ou xilazina, em gatos / Sedative and cardiorespiratory effects of methadone, alone or in combination with acepromazine or xylazine, in cats

Seis felinos com peso médio de 3,3±0,3 kg foram aleatoriamente submetidos a 6 tratamentos, com intervalo mínimo de 1 semana. Os animais receberam a administração intramuscular de solução fisiológica (controle), metadona (0,3 mg/kg), acepromazina (0,1 mg/kg), xilazina (1,0 mg/kg), acepromazina (0,05 mg/kg) + metadona (0,3 mg/kg) ou xilazina (0,5 mg/kg) + metadona (0,3 mg/kg). As freqüências cardíaca (FC) e respiratória (FR), a pressão arterial sistólica (PAS), a temperatura retal, o grau de sedação e o reflexo interdigital foram avaliados antes (basal) e após a administração dos tratamentos em intervalos específicos por 90 minutos. Nos animais tratados com xilazina ou xilazina/metadona, houve diminuição em FR, FC e na temperatura retal. Nos mesmos tratamentos, 1/6 e 2/6 animais não apresentaram reflexo interdigital em pelo menos um dos momentos avaliados. Nos animais que receberam a administração de 0,1 mg/kg de acepromazina, houve diminuição em PAS. Os escores de sedação foram mais elevados nos animais que receberam a administração de xilazina ou xilazina associada à metadona. A administração da metadona isolada ou associada à acepromazina resultou em sedação considerada insatisfatória e sinais de excitação em alguns animais. O uso da metadona isolado ou em associação à acepromazina foi considerado ineficaz quando se objetiva sedação moderada à intensa. A associação da metadona à xilazina produz sedação moderada à intensa, sendo esse efeito semelhante àquele observado após a administração da xilazina isoladamente em dose mais elevada.

Six cats weighting 3.3±0.3 kg were randomly allocated to 6 treatments, with at least one-week intervals. The cats received intramuscular administration of physiological saline (control), methadone (0.3 mg/kg), acepromazine (0,1 mg/kg), xylazine (1.0 mg/kg), acepromazine (0.05 mg/kg) plus methadone (0.3 mg/kg) or xylazine (0.5 mg/kg) plus methadone (0.3 mg/kg). Heart rate (HR), respiratory rate (RR), indirect systolic arterial pressure (SAP), rectal temperature, sedation score and pedal withdrawal reflex were evaluated before (baseline) and at selected intervals after treatment administration for 90 minutes. Respiratory rate, HR and rectal temperature decreased in cats given xylazine or xylazine plus methadone. In 1 out of 6 cats given xylazine and 2 out of 6 cats given xylazine/methadone, pedal withdrawal reflex was absent. In cats given 0.1 mg/kg of acepromazine, SAP decreased compared to baseline. Sedation scores were greater in cats given xylazine or xylazine plus methadone. Methadone alone or in combination with acepromazine did not produce a satisfactory degree of sedation and resulted in signs of excitement in some of the cats. Methadone alone or combination with acepromazine was not considered an effective protocol when moderate to deep sedation is required in cats. Methadone in combination with xylazine produces moderate to deep sedation, being this effect comparable to that achieved with a higher dose of xylazine alone.

Comparaçäo entre pericárdio bovino preservado em glicerina e malha de poliéster no reparo de falhas da parede abdominal em ratos / Comparison of glycerin preserved bovine pericardium and a polyester mesh for the repair of abdominal wall defects in rats

OBJETIVO: Comparar uma malha comercial de poliéster com o pericárdio bovino preservado em glicerina na reconstituiçäo de defeitos da parede abdominal. MÉTODOS: Foram utilizados 30 ratos, divididos em dois grupos eqüitativos. Efetuou-se uma excisäo retangular de 2,5 x 2 cm, incluindo toda a musculatura abdominal e peritônio. No grupo I a parede abdominal foi reparada com malha de poliéster e no grupo II com pericárdio bovino conservado em glicerina. Os animais foram sacrificados aos 15, 60 e 90 dias de pós-operatório, sendo o local cirúrgico avaliado macroscópica e histologicamente. RESULTADOS: Os animais do grupo I apresentaram aderências mais severas e em maior número quando comparados aos do grupo II; porém, sem comprometimento funcional. A análise histológica revelou incorporaçäo dos tecidos aos implantes, com maior resposta fibroblástica nos animais do grupo I. CONCLUSÄO: A malha de poliéster oferece maior resistência estrutural e resposta fibroblástica mais intensa; contudo, promove grande quantidade de aderências às vísceras abdominais, quando comparada ao pericárdio bovino.