A retrospective analysis of radiation therapy for the treatment of feline vaccine‐associated sarcoma*

We retrospectively evaluated predictive prognostic factors in 73 cats with vaccine‐associated sarcoma given postsurgical curative (n = 46, most with clean margins) or coarse fractionated radiotherapy (n = 27, most with either macroscopic disease or dirty margins). The former animals displayed a median survival of 43 months and a median progression free interval (PFI) of 37 months, the latter reached a median survival of 24 months and a median PFI of 10 months. In cats undergoing coarse fractionated therapy, factors predictive of a better outcome included lack of visible mass (n = 10) as opposed to macroscopic disease (n = 17, survival: 30 versus 7 months, P = 0.025; PFI: 20 versus 4 months, P = 0.01), adjuvant chemotherapy for gross disease (n = 5/17, survival: 29 versus 5 months, P = 0.04) and a smaller number of surgeries preceding radiation therapy (coeff = 0.41, P = 0.03). The Ki67 index was not predictive for survival. We concluded that postsurgical curative and coarse fractionated radiotherapy are effective legitimate options for managing vaccine‐associated sarcomas.     

Effects of exercise on the morphology of the myenteric neurons of the duodenum of Wistar rats during the ageing process

This study aimed to evaluate the effects of regular physical activity on the morphology of the myenteric plexus of the duodenum in rats during the ageing process. To this end, 45 Wistar rats were divided into three groups: C (sedentary – 6 months old), S (sedentary – 12 months old) and T (trained – 12 months old). The animals of group S were given with a physical activity programme consisting of a 10-min-treadmill workout once a week. The animals of group T were submitted to the physical activity programme five times a week. Their duodenums were collected and submitted to the techniques of nicotinamide adenine dinucleotide (NADH)-diaphorase enzyme histochemistry for whole-mount preparations and transmission electron microscopy. No differences in the constitution of the myenteric plexuses were found when the sedentary and trained groups were compared with the control group. The ultrastructural features were similar for the three groups. However, it was verified that the physical activity of the trained animals resulted in a similar myenteric neuron morphology to that of the adult animals (6 months old), thereby confirming its beneficial effect, as the sedentary animals had larger alterations in the collagen fibrils and the basal membrane that occur through ageing. The quantitative analysis showed that the NADH-diaphorase positive neurons decreased with ageing and increased with physical activity ( P  > 0.05). No significant alteration ( P  > 0.05) in the neuronal profile area of the NADH-diaphorase positive neurons has been observed with ageing.     

The effect of dietary supplementation with 9-cis:12-trans and 10-trans:12-cis conjugated linoleic acid (CLA) for nine months on serum cholesterol, lymphocyte proliferation and polymorphonuclear cells function in Beagle dogs

Conjugated linoleic acids (CLA), 9-cis:11-trans and 10-trans:12-cis, have been shown to be able to modify some immune cells parameters and plasma lipids in a variety of experiment models. Since lymphocytes and polymorphonuclear cells (PMNC) have a large spectrum functions in the immune response, the knowledge in this field has to be expanded. Beagle dogs were fed a control diet or a CLA supplemented diet for nine months. Blood was collected for biochemical analysis and lymphocyte and PMNC isolation. PMNC were assayed for lysosome content, phagocytic activity and superoxide anion production. A lymphocyte proliferation capacity assay was done. The CLA fed dogs had a 34% reduction in total cholesterol (P < 0.05), 28% in LDL (P < 0.05) and 28% non-HDL-cholesterol (P < 0.05). Neither of the PMNC parameters evaluated demonstrated significant alteration. Lymphocytes from CLA group increased by 45% their mitotic capacity (P < 0.05). Our study demonstrates that CLA can successfully modify the lipid profile of dogs (monogastrics) when fed at reasonable levels, but did not significantly alter inflammatory function as would generally predicted. Further, we had some indication that CLA modulated T cell responsiveness.     

The oxidant/antioxidant equilibrium in horses

Since "free radical research" started in 1954, understanding the role of oxidants and antioxidants in physiological and pathological conditions has increased continuously. Oxidants are essentially generated by metabolic enzymes, inflammatory cells and mitochondrial electron leakage; they are indispensable for the cellular redox regulation and may, under certain conditions, have a pro-inflammatory stimulatory role. Endogenous and exogenous antioxidants counterbalance the oxidative processes and so maintain the oxidant/antioxidant equilibrium. Excessive oxidant generation or antioxidant insufficiency can lead to oxidative stress. The aims of this review are: (1) to provide an insight into the concept of the oxidant/antioxidant equilibrium by briefly introducing the oxidant and the antioxidant systems; (2) to describe how the oxidant/antioxidant equilibrium or oxidative stress can be evaluated in horses, and (3) to summarise current knowledge about oxidative stress in equine medicine and equine exercise physiology.     

Use of latissimus dorsi and abdominal external oblique muscle for reconstruction of a thoracic wall defect in a cat with feline osteochondromatosis

A 4-year-old, male castrated European shorthair cat was presented with a firm mass palpable on the right caudal rib cage. Lateral and ventrodorsal radiographs of the thorax revealed a 4x3x2cm large, expansile and radiodense mass originating from the distal part of the 13th rib. After removal of the tumour, which was histopathologically confirmed as feline osteochondromatosis, the diaphragm, omentum, external abdominal oblique and latissimus dorsi muscles were used to reconstruct the defect. Feline osteochondromatosis is induced by retroviruses, eg, feline leukaemia virus, for which the cat tested positive. The tumour was removed for palliative reasons, because such tumours have the tendency to transform into osteosarcomas. Six months after the surgical excision the cat showed no clinical signs of reoccurrence.     

In vivo and in vitro efficacy of zoledronate for treating oral squamous cell carcinoma in cats

BACKGROUND: Feline oral squamous cell carcinoma (OSCC) may cause painful bone destruction. Given the local invasiveness and rapid clinical progression of OSCC, conventional therapies are often palliative. In human cancer patients, zoledronate exerts anticancer effects by inhibiting tumor-induced angiogenesis and malignant osteolysis. HYPOTHESIS: Zoledronate will exert in vitro and in vivo anti-angiogenic and antiresorptive effects in feline OSCC. ANIMALS: Eight cats with OSCC were prospectively treated with zoledronate and conventional treatment modalities. METHODS: In vitro, zoledronate's effects in modulating soluble vascular endothelial growth factor (VEGF) secretion and receptor activator of nuclear factor kappaB (NF-kappaB) ligand (RANKL) expression were investigated in a feline OSCC cell line (SCCF1). In vivo, basal serum C-telopeptide (CTx) concentrations were compared among normal and OSCC-bearing cats, and the biologic effects of zoledronate administration in cats with naturally occurring OSCC were quantified by serially assessing circulating serum VEGF and CTx concentrations. RESULTS: In vitro, zoledronate concentrations greater than 3 microM reduce soluble VEGF secretion in the SCCF1 cell line. The expression of RANKL in the SCCF1 cell line was also modulated by zoledronate, with low concentrations (3 microM) decreasing but higher concentrations (30 microM) increasing RANKL expression in comparison with untreated cells. In vivo, cats with bone-invasive OSCC had greater serum CTx concentrations in comparison with geriatric, healthy controls. Treatment with zoledronate rapidly decreased circulating serum VEGF and CTx concentrations in cats with spontaneously occurring OSCC. CONCLUSIONS AND CLINICAL IMPORTANCE: Zoledronate exerts in vitro and in vivo effects that may favor the slowing of tumor growth and pathologic bone turnover associated with OSCC.     

Metabolic alkalosis: a quick reference.

This article serves as a quick reference for metabolic alkalosis. Guidelines for analysis and causes, signs, and a stepwise approach are presented.