Point mutations in BHV-1 Us3 gene abolish its ability to induce cytoskeletal changes in various cell types

The Us3 gene is conserved among alphaherpesviruses and codes for a protein kinase, a multifunctional protein involved in many phases of virus infection, like nuclear egress, modulation of apoptosis and modification of the cellular cytoskeleton. Bovine herpesvirus (BHV-1), a member of the Alphaherpesvirinae, contains an open reading frame homologous to Us3 of other herpesviruses, which has been identified as a serine/threonine kinase (Takashima, Y., Tamura, H., Xuan, X., Otsuka, H., 1999. Identification of the Us3 gene product of BHV-1 as a protein kinase and characterization of BHV-1 mutants of the Us3 gene. Virus Res. 59, 23–34). To study the activity of BHV-1 Us3, we have cloned its sequence under control of the human cytomegalovirus (HCMV) promoter/enhancer and introduced it into a recombinant baculovirus (Bac Us3). Confocal microscopy analysis showed profound cytoskeletal modifications in various BHV-1-permissive and non-permissive cells transduced with BacUs3. We observed that Us3 expression changed cellular shape and induced formation of long microtubule-containing cell projections, a phenomenon which had also been observed in cells expressing pseudorabies virus Us3. The intracellular localization of Us3 was mostly nuclear but when the protein accumulated it could be detected in the cytoplasm, cell membranes and projections. Mutated forms of BHV-1 Us3 with point mutations near or within the kinase catalytic domain did not affect cell morphology indicating that kinase activity of BHV-1 Us3 is required for its cytoskeleton remodelling function.     

Presence of Caffeic Acid in Flaxseed Lignan Macromolecule

Phenolic compounds were extracted from defatted flaxseeds using ethanol-dioxane (1:1, v/v). The crude extract obtained was purified using Amberlite XAD-16 column chromatography with water and methanol as mobile phases. RP-HPLC and SE-HPLC showed a lignan macromolecule (LM) as a dominant phenolic compound in the purified extract. After the alkaline hydrolysis of LM caffeic acid glucoside (CaAG) was isolated using a semi-preparative HPLC and its structure was confirmed by LC-ESI-MS. In LM of the investigated flaxseed, one molecule of caffeic acid corresponded with five molecules of p-coumaric acid and two molecules of ferulic acid. The presence of caffeic acid in the lignan molecule might be very beneficial due to its high antioxidant activity.     

Intracardiac electrophysiological conduction parameters in adult dogs

Background: Invasive electrophysiology study (EPS) is one of the most important adjunct tests for the evaluation of arrhythmias in human medicine. However, EPS is neither well known nor widely used in veterinary medicine.

Objective: To define the values for intracardiac conduction parameters determined during invasive EPS in dogs.

Animals and methods: The study included 16 admitted dogs of various breeds, sex and ages and 6 control Beagles. In the Beagles, EPS was performed twice at 6-month intervals in order to verify the reproducibility of the results.

Results: No significant differences were found between the results of the baseline and repeated EPS performed in the Beagles. We found retrograde conduction in 13 (59%) out of 22 dogs and including 4 (31%) animals with concomitant ‘jumps’ in the atrioventricular node conduction curve, pointing to the presence of dual conduction in this node. The mean values of the AV and retrograde VA Wenckebach points equaled to 220 and 360 ms, respectively, suggesting that the capability of the descending route is higher than that of the ascending route.

Conclusion: The values determined in this study may be helpful in early detection of abnormalities in the electrical conduction system of the heart.     

Influence of bitches sex pheromones on the heart rate and other chosen parameters of blood flow in stud dogs (Canis familiaris)

The aim of this study was to verify the usefulness of the measurement of chosen cardiovascular activity parameters for examination of sex pheromones effects in male dogs. We evaluated the influence of the bitches' sexual pheromones (BSP) on heart rate (HR) with the use of a Holter monitor, and chosen parameters of blood flow in vessels of penis, testes and kidney, with color-coded and pulsed Doppler ultrasonography. We found that the BSP increased HR in all examined males even without showing any other signs of arousal. There were no changes in the RI (resistant index) and PI (pulsative index) in any trials during the pheromone presentation. The increase in blood flow intensity was noted in penile vessels but not in the testes and kidney. We concluded that measurement of flow intensity in the penis as well as the changes in heart rate as the male's reaction to the BSP can be useful in research concerning sex pheromones in dogs.     

Novel Biodegradable Potato Starch-based Compositions as Candidates in Packaging Industry,Safe for Marine Environment

About 70 % of our planet’s surface is covered by seas and oceans to which even 10 million tons of waste go every year. It makes these places the largest global landfills, containing up to 90 % of plastic waste. In this article we present the results of research on novel starch-based compositions expected to be more safe for the marine environment. For these purpose biopolymers such as, thermoplastic starch (TPS), polylactide (PLA) and poly(vinyl alcohol) (PVA) were reactive extruded and formed into films by high-pressure compressing. Their physical, thermal and mechanical properties were examined. Compositions were tested in seawater collected from the Gulf of Gdansk Baltic Sea. The obtained samples were completely disintegrated after 3 weeks. BOD test in the presence of bacteria pseudomonas augerinosa confirmed biodegradation of prepared compositions. The impact assessment of received materials on the marine environment was also evaluated by degradation tests in the presence of Phaeodactylum tricornutum diatom. Cells growth of Phaeodactylum tricornutum diatoms was only slightly inhibited in the presence of TPS/PLA/PVA compositions.     

Humic acid and biochar as specific sorbents of pesticides

Purpose

The aim of the research was to compare the effect of two types of organic sorbents—humic acid (HA) and biochar (BC)—in sorption-desorption processes of different polar pesticides, which residues are commonly present in arable soils and are potentially harmful for the environment. It also aims to advance the understanding of behavior of both ionizable and nonionizable pesticides in the presence of BC and HA in soils.

Materials and methods

Three different classes of pesticides were investigated: carbamates (carbaryl and carbofuran), phenoxyacetic acids (2,4-dichlorophenoxyacetic acid (2,4-D) and 4-chloro-2-methylphenoxyacetic acid (MCPA)), and aniline derivatives (metolachlor). Investigated humic acid was extracted by Shnitzer’s method from topsoil horizon of arable Gleyic Phaeozem. Biochar was produced from wheat straw in gasification process at 550 °C, remaining 30 s in the reactor. To obtain the experimental goal structural properties of both sorbents were determined and sorption-desorption experiments conducted. To the investigated organic matter samples (HA or BC), 10 or 15 mg L^?1 pesticide solutions in 10 mM CaCl₂ were added and the mixtures were shaken for 24 h. Afterwards, the samples were centrifuged and supernatants analyzed by LC-MS/MS for the pesticide content. Analogous experiment was performed for desorption studies (samples refilled with 10 mM CaCl₂).

Results and discussion

Humic acids exhibited strong affinity for the ionic substances, for which high-percentage uptake (74.6 and 67.9% initial dose of 2,4-D and MCPA, respectively) was obtained. Retention of nonionic carbamates on HA was much weaker (35.4% of carbofuran and 10.2% of carbaryl sorbed). Sorption of carbamates to BC was significantly reduced (76.4–84.3%) by the alkaline hydrolysis. Metolachlor was bound comparably strong both by HA (72.9%) and BC (70.2%), although different mechanisms governed its sorption. Noticeable desorption occurred only in the case of 2,4-D bound to HA (over 50%), whereas other studied compounds were released from HA within the range of 4.4–10.8% of the dose sorbed. Oppositely to HA, desorption of all studied pesticides from BC was completely inhibited, except for 2,4-D (3.7% desorbed).

Conclusions

Investigated humic acid has high affinity to polar, ionic pesticides of high water solubility, which are sorbed via specific interactions with HA functional groups. Studied biochar, due to its moderately hydrophobic character, preferentially attracts nonionic pesticides of relatively high logP values and low water solubility. Hydrophobic bonding is postulated as a main mechanism of their attraction to BC. Besides sorbent structural properties, pH is the main factor governing sorption equilibria in the studied mixtures.

     

Effect of storage on quality traits of the semimembranosus muscle of farmed fallow deer (Dama dama) bucks and does

A total of 12 farmed fallow deer bucks and 12 does aged 31–32 months were included in a study on the effect of storage in vacuum packaging on the functionality of venison of the Semimembranosus muscle. All the analyzed meat quality traits were not affected by sex. The storage of meat in vacuum led to: an increase of pH (by 0.13 units; P = 0.001), L* (by 1.85 units; P = 0.002), a* (by 1.15 units; P = 0.013) and chroma (by 1.16 units; P = 0.016), a decrease of free water (by 6.62 percentage points (p.p.); P = 0.001) and water‐holding capacity (cm²) (by 29.61%; P = 0.001), and the increase of dry matter content (by 0.67 p.p.; P = 0.001). The results indicate that the chilled storage of venison caused the stabilization of pH and color, improvement of water‐holding capacity, with no negative effect on the proximate chemical composition. The quality of deer meat obtained from does and bucks was similar.     

Lubrication properties of protein aggregate dispersions in a soft contact

The lubrication, rheological, and molecular properties of two different protein aggregate dispersions were compared: globular aggregates of whey protein isolate (WPI) and fibrillar aggregates of ovalbumin from egg white. These dispersions are models for the lubricating fluid that is present between the tongue and the palate when consuming liquid or gelled products. To simulate oral conditions, a commercial tribometer was modified so that soft rubber surfaces could be used. This allowed us to measure friction at low contact pressures similar to those present between the tongue and palate. Clear correlations were observed between the measured friction coefficients and specific properties of the lubricating fluid such as protein concentration and aggregate size and shape. Furthermore, surface properties like elasticity, surface-surface interactions, and surface roughness had a significant effect on the friction under conditions that are relevant for texture perception. We conclude that in vitro measurements at low contact pressure provide valuable information for understanding and controlling food properties that modulate oral friction.