Concentration of extracellular vesicles isolated from blood relative to the clinical pathological status of dogs with mast cell tumours

Extracellular vesicles (EVs) are membrane‐enclosed fragments shed from all cell types, including tumour cells. EVs contain a wide range of proteins, biolipids and genetic material derived from mother cells and therefore may be potential biomarkers for tumour diagnosis, disease progression and treatment success. We studied the effect of canine mast cell tumours (MCTs) on EV concentrations in blood isolates in association with MCT's histological grade, Ki‐67 proliferative index, KIT‐staining pattern and number of PLT. The average EV concentration in blood isolates from nine dogs with MCTs was considerably higher than that in blood from eight healthy dogs. But there were no statistically significant differences in EVs concentration in the population of dogs with MCT according to a different histological grade of malignancy (Patnaik, Kiupel), KIT‐staining pattern and Ki‐67 proliferation index. The results show that these variables statistically do not significantly predicted EV concentrations in blood isolates (P > .05), except the KIT‐staining pattern I which added statistically significantly to the prediction (P < .05). The results confirmed the impact of neoplasms on the morphological changes to cell membranes, which result in greater vesiculability and higher EV concentrations.     

Characterization of canine microglial cells isolated ex vivo

Microglia are the principal immune effector elements of the brain sharing immunophenotypic and functional characteristics of macrophages as well as of antigen presenting cells (APCs). The purpose of this study was to isolate canine microglial cells and make them available for ex vivo characterizations of their functions and immunophenotype. After isolation, carried out by density gradient centrifugation, microglial cells accumulated on distinct interfaces of 1.077 and 1.066 g/ml of a Percoll gradient. Identification of microglial cells in other species is realized by their specific immunophenotype of CD11b/c+ and CD45low. Our results indicate, that expression of CD45 is very low or even absent in canine microglial cells. In addition, they expressed CD18 and CD11b/c+, as determined by flow cytometry and immunohistochemistry. Fourteen additional monoclonal antibodies (mAbs) were used to characterize and compare canine microglial cells with monocytes. Microglia and monocytes can be clearly distinguished by their differential expression intensity of surface antigens (CD45, CD44, CD14). Functional characterization was assessed by a reactive oxygen species (ROS)-generation test and phagocytosis assay using flow cytometry. In conclusion, ex vivo examination of microglia is possible in dogs and most probably reflects the conditions in vivo. The measurement of tissue culture artifacts can be largely avoided using this method.     

Epidural myelolipoma in a Husky-cross: a case report

Epidural spinal myelolipoma was diagnosed in an 11.5-year-old castrated male Husky-cross that was evaluated at the veterinary teaching hospital due to progressive thoracolumbar spinal hyperaesthesia and mild proprioceptive pelvic limb ataxia. A focal, ill-defined mildly inhomogenous extradural mass lesion was detected by MRI. The dog was euthanized. At necropsy an extradurally located reddish mass of about 2.5 cm in diameter was present in the vertebral canal. The mass was identified histopathologically as an epidural myelolipoma.     

Effects of excessive dietary zinc or zinc/cadmium and tapeworm infection on the biochemical parameters in rats

The main objective of this study was to determine which biochemical blood parameters can serve as indicators of Zn or Zn/Cd burden and tapeworm infection. This study was performed on 44 Wistar male rats during a 6-week period, when rats were or were not fed a zinc/cadmium rich diet and were or were not infected with tapeworms (Hymenolepis diminuta). Total protein, albumin, urea, glucose, triacylglycerols, non-esterified fatty acids, cholesterol, alkaline phosphatase, aspartate aminotransferase, uric acid, Mg, Ca, P and Zn levels were analysed. Control rats with tapeworm infection had significantly higher (p ≤ 0.05) total protein, urea and phosphorus concentrations than did rats unaffected by any experimental factor. Rats given overdoses of zinc lactate exhibited significantly lower glucose levels than did the other rats, especially those infected with tapeworms. Low glucose level in uninfected rats indicate a Zn overdose; high doses of zinc lactate likely decrease levels of glucose via cortisol, which is released during stress. Rats fed the Zn/Cd hyperaccumulating plant Arabidopsis halleri and infected with tapeworms had significantly higher (p ≤ 0.01) cholesterol and urea levels but lower zinc, triacylglycerol, and alkaline phosphatase levels than did rats fed the same diet but free of tapeworms. The increase of alkaline phosphatase level in uninfected rats may indicate both Zn/Cd burden and rat liver damage. Overall, this study not only supports the theory that H. diminuta can serve as a promising model for helminth therapy of the host mammal but also confirmed that this tapeworm is capable to protect somehow the host organism from the harmful effects of heavy metals.     

Incidence of Insect Bite Hypersensitivity in a Small Population of Warmblood Horse Breed in the Czech Republic

Insect bite hypersensitivity (IBH) is a serious equine disease with a complex etiology, affecting many breeds. The availability of a small closed population with a relatively high incidence of IBH (28%) offered the chance to contribute to a better understanding of the etiology of IBH. All 736 Warmblood horses, kept in lowland floodplain meadows in the Czech Republic, were analyzed in the period 1998-2010. The morbidity rate in the offsprings of particular stallions was significantly different; the lowest was 10% and the highest 75%. The assumption that the highest occurrence of healthy offspring would be in healthy parents and vice versa was confirmed. The sex of the offsprings was not significant. To decline the disorder prevalence in this population, stud stallions should be IBH negative; afflicted mares can be tolerated to a certain extent, but their male offspring must never be used as stud. Heredity control is necessary, and stallions with IBH+ offspring should be culled. There is to date no reliable treatment available, and therefore, the development of preventive measures is particularly important. The incidence of IBH could be lowered by prudent breeding, and thus immunotherapy and complex herd management would not be necessary. However, this would be a long-term and complex process.     

Modelling the effects of forest management intensification on base cation concentrations in soil water and on tree growth in spruce forests in Sweden

The study investigated the effects of forest residue extraction on tree growth and base cations concentrations in soil water under different climatic conditions in Sweden. For this purpose, the dynamic model ForSAFE was used to compare the effects of whole-tree harvesting and stem harvesting on tree biomass and the soil solution over time at 6 different forest sites. The study confirmed the results from experimental sites showing a temporary reduction of base cation concentration in the soil solution for a period of 20–30 years after whole-tree harvesting. The model showed that this was mainly caused by the reduced inputs of organic material after residue extraction and thereby reduced nutrient mineralisation in the soil. The model results also showed that whole-tree harvesting can affect tree growth at nitrogen-poor forest sites, such as the ones in northern Sweden, due to the decrease of nitrogen availability after residue removal. Possible ways of reducing this impact could be to compensate the losses with fertilisation or extract residue without foliage in areas of Sweden with low nitrogen deposition. The study highlighted the need to better understand the medium- and long-term effects of whole-tree harvesting on tree growth, since the results suggested that reduced tree growth after whole-tree harvesting could be only temporary. However, these results do not account for prolonged extraction of forest residues that could progressively deplete nutrient pools and lead to permanent effects on tree growth.

     

Fresh-wood bending: linking the mechanical and growth properties of a Norway spruce stem

To provide data and methods for analyzing stem mechanics, we investigated bending, density and growth characteristics of 207 specimens of fresh wood from different heights and radial positions of the stem of one mature Norway spruce (Picea abies L. Karst.) tree. From the shape of each stress-strain curve, which was calculated from bending tests that accounted for shear deformation, we determined the modulus of elasticity (MOE), the modulus of rupture (MOR), the completeness of the material, an idealized stress-strain curve and the work involved in bending. In general, all mechanical properties increased with distance from the pith, with values in the ranges of 5.7-18 GPa for MOE, 23-90 MPa for MOR and 370-630 and 430-1100 kg m(-3) for dry and fresh wood densities, respectively. The first three properties generally decreased with stem height, whereas fresh wood density increased. Multiple regression equations were calculated, relating MOR, MOE and dry wood density to growth properties. We applied these equations to the growth of the entire stem and considered the annual rings as superimposed cylindrical shells, resulting in stem-section values of MOE, MOR and dry and fresh densities as a function of stem height and cambial age. The standing tree exhibits an inner stem structure that is well designed for bending, especially at a mature stage.