Genomic and genetic aspects of heart failure in dogs - a review

The most common causes of heart failure in dogs are valvular disease, predominantly endocardiosis, and myocardial disease, predominantly dilated cardiomyopathy. They are related to changes in the expression of several genes in the heart muscle and in peripheral blood nuclear cells which could be considered as prognostic or diagnostic markers of heart disease in dogs. Since many human genetic markers of heart failure have turned out to be useless in dogs, the screening for genomic markers of canine heart failure could give more insight into the molecular pathology of these diseases and aid the development of new treatment strategies.     

Effects of cortisol on pregnancy rate and corpus luteum function in heifers: an in vivo study

To determine whether glucocorticoids affect the function of the bovine corpus luteum (CL) during the estrous cycle and early pregnancy, we examined the effects of exogenous cortisol or reduced endogenous cortisol on the secretion of progesterone (P4) and on pregnancy rate. In preliminary experiments, doses of cortisol and metyrapone (an inhibitor of cortisol synthesis) were established (n=33). Cortisol in effective doses of 10 mg blocked tumor necrosis factor-induced prostaglandin F(2α) secretion as measured by its metabolite (PGFM) concentrations in the blood. Metyrapone in effective doses of 500 mg increased the P4 concentration. Thus, both reagents were then intravaginally applied in the chosen doses daily from Day 15 to 18 after estrus (Day 0) in noninseminated heifers (n=18) or after artificial insemination (n=36). Pregnancy was confirmed by transrectal ultrasonography between Days 28-30 after insemination. Plasma concentrations of P4 were lower in cortisol-treated heifers than in control heifers on Days 17 and 18 of the estrous cycle (P<0.05). However, the interestrus intervals were not different between control and cortisol-treated animals (P>0.05). Moreover, metyrapone increased P4 and prolonged the CL lifespan in comparison to control animals (P<0.05). Interestingly, in inseminated heifers, cortisol increased the pregnancy rate (75%) compared with control animals (58%), whereas metyrapone reduced the pregnancy rate to 16.7% (P<0.05). The overall results suggest that cortisol, depending on the physiological status of heifers (pregnant vs. nonpregnant), modulates CL function by influencing P4 secretion. Cortisol may have a positive influence on CL function during early pregnancy, leading to support of embryo implantation and resulting in higher rates of pregnancy in heifers.     

Effects of the commercial extract of aronia on oxidative stress in blood platelets isolated from breast cancer patients after the surgery and various phases of the chemotherapy

Since the extract from berries of Aronia melanocarpa presents antioxidative properties in plasma and in blood platelets, not only from healthy group, but also from patients with benign breast diseases and in patients with invasive breast cancer before surgery, the aim of our present study was to evaluate the oxidative stress by measuring the level of various biomarkers of this process such as the generation of superoxide anion radicals (O(2)(-·)), the amount of carbonyl groups and 3-nitrotyrosine in proteins or the amount of glutathione in blood platelets isolated from breast cancer patients after the surgery and after various phases of the chemotherapy in the presence of A. melanocarpa extract (Aronox) in vitro. We demonstrated in platelet proteins from patients with invasive breast cancer (after the surgery and after various phases of the chemotherapy) higher level of carbonyl groups than in control healthy group. The level of 3-nitrotyrosine in platelet proteins from patients with invasive breast cancer was also significantly higher than in healthy subject group. We observed an increase of other biomarkers of oxidative stress such as O(2)(-·) and a decrease of GSH in platelets from patients with breast cancer (after the surgery and after various phases of the chemotherapy) compared to the healthy group. In model system in vitro our results showed that the commercial extract from berries of A. melanocarpa due to antioxidant action, significantly reduced the oxidative/nitrative stress in platelets from patients with invasive breast cancer caused by the surgery and various phases of the chemotherapy.     

Pestivirus and alphaherpesvirus infections in Swedish reindeer (Rangifer tarandus tarandus L.)

Herding semi-domesticated reindeer has economic and social value for Sami people in the northern territories of Fennoscandia. However, with the intensification of reindeer husbandry, interspecies transmission of pathogens between reindeer and domestic animals may become a problem, especially for countries such as Sweden, Norway, and Finland where pestivirus and alphaherpesvirus have been eradicated in domestic ruminants. This study, which included 1158 Swedish reindeer, showed relatively high prevalence of antibodies against bovine viral diarrhoea virus (BVDV) (32%) and bovine herpesvirus-1 (BoHV-1) (53%). Adult animals were more often seropositive for BVDV and BoHV-1 (50% and 78%, respectively) than were calves (18 and 11%, respectively). While the seroprevalence of alphaherpesvirus was similar in different herding districts, pestivirus seropositivity was highest in the South and diminished towards the North of the Swedish reindeer herding area. High correlation of the seropositivity against both pathogens at both individual and herd levels may indicate possible mutual synergetic effects and may be explained by the immunosuppressive nature of the viruses. While alphaherpesvirus seroprevalence was probably related to putative cervid herpesvirus 2 (CvHV-2), the pestivirus infecting reindeer remains undefined. The virus neutralisation test of reindeer sera using different pestivirus strains, revealed higher titres against Border disease virus strains like 137/4 (BDV-1) and Reindeer-1 (BDV-2) than against BVDV-1. However, the virus was not identified by real time RT-PCR in any of the samples (n=276) from seronegative reindeers. The study showed that pestivirus and alphaherpesvirus infections are endemic in the Swedish reindeer population.     

Seroepidemiology of Mycoplasma hyopneumoniae in pigs from farrow-to-finish farms

A prospective study was carried out on three intensive farrow-to-finish farms. The aims were to estimate the incidence of Mycoplasma hyopneumoniae infection, to determine when pigs become infected and the pattern of transmission of infection and to verify the relationship between seroconversion and clinical signs. One batch of pigs per farm was followed from farrowing-to-slaughter. Blood samples were taken at 10, 27, 70, 94, 125 and 147 days of age, from 44, 48 and 44 pigs per farm. Colostrum and blood samples were also taken from the sows. Animals were checked clinically once a week and coughing rates were recorded. Antibodies against M. hyopneumoniae were detected by a blocking ELISA. At 27, 70 and 94 days of age most pigs on the three farms were seronegative, suggesting that no circulation of M. hyopneumoniae occurred during the growing period. Thereafter, a high proportion of pigs seroconverted, indicating that infection occurred soon after the transfer of the animals to the finishing houses. Differences were detected between farms in the incidence of seroconversion. Seropositive pigs were widely distributed among the finishing pens, suggesting that in addition to direct contact, other methods of transmission, such as indirect or airborne transmission, may have been important. Coughing started at around the same time as seroconversion. The results showed that the critical period for the transmission of M. hyopneumoniae is around the beginning of the finishing period, when pigs have low concentrations of antibodies against the agent.     

Characterization of turkey coronavirus from turkey poults with acute enteritis.

The present study was to characterize turkey coronavirus associated with turkey poult enteritis and mortality. Intestinal contents or intestines from affected turkey poults and inoculated turkey embryos contained coronaviruses as revealed by electron microscopy or were positive for turkey coronavirus by immunofluorescent antibody assay. Sucrose density gradient ultracentrifugation of the virus-containing intestinal homogenate yielded two opalescent bands corresponding to the buoyant densities of 1.14-1.15 and 1.18-1.20 g/ml, respectively. Coronaviral particles from intestinal contents or the sucrose density gradient preparation were mainly spherical in shape and had envelope and central depression. They were surrounded by a fringe of regularly spaced petal-shaped projections attached to the particles by a short stalk. Purified viruses hemagglutinated rabbit erythrocytes with a titer of 16. Major protein bands of purified viruses analyzed by SDS-PAGE were located at 200, 100-110, 50-60, and 30-35 kDa. The patterns of protein bands were consistent with those of Minnesota or Quebec turkey coronavirus isolates. A 568 bp nucleotide fragment of turkey coronavirus spike protein gene was amplified from RNA of inoculated turkey embryo intestine or purified virus. Sequence analysis of the 568 bp PCR product revealed high degree of identity with the corresponding spike protein gene sequence of human and bovine coronaviruses. The results indicated that turkey coronavirus was associated with turkey poults with acute enteritis.     

Thermally initiated solvent-free radical modification of beech (Fagus sylvatica) wood

A procedure for rapidly modifying beech wood using a thermally initiated solvent-free grafting system was examined. In the modification, butyl acrylate and butyl methacrylate were used as vinyl monomers. Free radicals were generated from 2,2′-azobis(2-methylpropionitrile) or benzoyl peroxide at 103 and 180 °C by contact heating of the modified material. Chemical changes in the material were investigated by FTIR and X-ray photoelectron spectroscopies. The modification resulted in decreased surface wetting of the material manifested by increased water contact angles. The hardness of the resultant material decreased, while its color changed by the effect of temperature. It was shown that the approach allowed for efficient thermal-initiated modification of wood with rapid contact heating.     

Metabolic rate and body temperature of an African sunbird,Nectarinia Chalybea: daily rhythm and the effect of ambient temperature

The oxygen consumption (VO₂) of the lesser double-collared sunbird, Nectarinia chalybea. was measured at ambient temperatures (Ta) from 7 to 35°C. The diel variation in body temperature (Tb) and wet thermal conductance (C) was also determined. The sunbirds (mean mass 8,36 g ± S.E. 0.21 g) showed a pronounced diel cycle of VO₂, with a mean reduction of 50% at night. Basal metabolic rate was estimated to be 3.23 ml O₂/g.h, which is 88% of the predicted value for a passerine bird of this size. There was a mean reduction in Tb of 3.6°C at night. Both day and night values of Tb decreased with decreasing Ta, as did individual values of C. Winter breeding in the south-west Cape is energetically stressful for lesser double-collared sunbirds, but they have the physiological capacity to reduce their energy expenditure substantially at night.     

Pseudodidymella fagi in Slovakia: First detection,morphology and culture characteristics

Pseudodidymella fagi, described from infected leaves of Fagus crenata in Japan, has recently been spreading in Europe, where it causes leaf blotch of European beech Fagus sylvatica. In the years 2008–2016, an outbreak of P. fagi was observed on European beech in Switzerland, Germany and Austria, and it is reported here for the first time from Slovakia where it was detected in 2017. The identification of the pathogen is supported by the morphological analyses of material observed in vivo and in vitro and molecular analyses based on ITS sequences. Detailed morphological characterization of cultures based on European material, on F. sylvatica, is provided here for the first time.     

Development of a rapid method for the sequential extraction and subsequent quantification of fatty acids and sugars from avocado mesocarp tissue

Methods devised for oil extraction from avocado (Persea americana Mill.) mesocarp (e.g., Soxhlet) are usually lengthy and require operation at high temperature. Moreover, methods for extracting sugars from avocado tissue (e.g., 80% ethanol, v/v) do not allow for lipids to be easily measured from the same sample. This study describes a new simple method that enabled sequential extraction and subsequent quantification of both fatty acids and sugars from the same avocado mesocarp tissue sample. Freeze-dried mesocarp samples of avocado cv. Hass fruit of different ripening stages were extracted by homogenization with hexane and the oil extracts quantified for fatty acid composition by GC. The resulting filter residues were readily usable for sugar extraction with methanol (62.5%, v/v). For comparison, oil was also extracted using the standard Soxhlet technique and the resulting thimble residue extracted for sugars as before. An additional experiment was carried out whereby filter residues were also extracted using ethanol. Average oil yield using the Soxhlet technique was significantly (P < 0.05) higher than that obtained by homogenization with hexane, although the difference remained very slight, and fatty acid profiles of the oil extracts following both methods were very similar. Oil recovery improved with increasing ripeness of the fruit with minor differences observed in the fatty acid composition during postharvest ripening. After lipid removal, methanolic extraction was superior in recovering sucrose and perseitol as compared to 80% ethanol (v/v), whereas mannoheptulose recovery was not affected by solvent used. The method presented has the benefits of shorter extraction time, lower extraction temperature, and reduced amount of solvent and can be used for sequential extraction of fatty acids and sugars from the same sample.