Impact of oxidative stress on male fertility - a review

Oxidative stress is a state related to increased cellular damage caused by oxygen and oxygen-derived free radicals known as reactive oxygen species (ROS). It is a serious condition, as ROS and their metabolites attack DNA, lipids and proteins, alter enzymatic systems and cell signalling pathways, producing irreparable alterations, cell death and necrosis. While small amounts of ROS have been shown to be required for several functions of spermatozoa, their excessive levels can negatively impact the quality of spermatozoa and impair their overall fertilising capacity. These questions have recently attracted the attention of the scientific community; however, research aimed at exploring the role of oxidative stress and antioxidants associated with male fertility is still at its initial stages. This review summarises the current facts available in this field and intends to stimulate interest in basic and clinical research, especially in the development of effective methods for the diagnosis and therapy of semen damage caused by oxidative stress.     

Technological Properties of Yeast Produced Surface Active Compounds in Connection with Their Application in Clean-Up Technologies

Biologically produced surfactants （SACs） can mobilize and solubilize non-aqueous phase liquids （NAPL） adsorbed onto soil constituents. The interest in microbial surfactants has increased during recent years due to their lower toxicity, higher biodegradability, selectivity and specific activity under extreme conditions than synthetic SACs. Main output of the project represents preparation of this yeast biosurfactant intended for washing of matrices contaminated by NAPL. The influence of cultivation media composition on biosurfactant production was studied and basic properties （critical micelle concentration （CMC）, minimum surface tension） of isolated biosurfactants were compared with properties of synthetic surfactant with surface tension measurement. The interracial tension of the systems containing aqueous solutions of different concentrations and non-polar substances was measured with petroleum compounds （kerosene Jet A-l）, aromatic and aliphatic hydrocarbons （represented by toluene and hexane）. The solution of biosurfactant Yarrowia lipolytica （YAR） in the concentration range of 0-500 mg/L reduced interracial tension by 80% in all representative systems with model contaminants; biosurfactant Candida bombicola （CAN） was less efficient. Solubilization properties were proved with toluene and hexachlorocyclohexane （HCH） isomers alpha and gamma, and effective concentration of biosurfactants was determined as 100 mg/L for toluene and HCH. SACs produced by lipophilic yeast with non-toxic and non-pathogenic status （Yarrowia lipolytica, Candida sp., etc.） seem to be very promising. The results obtained will be used for the application of biosurfactants in the clean-up technologies as agents for the mobilization of non-polar contaminants as well as for stimulation of bioremediation processes.     

Nutritional evaluation of genetically modified maize corn performed on rats.

The aim of this study was to determine the composition and nutritional value of conventional and transgenic, so-called Roundup Ready (RR) maize with an introduced gene of glyphosate resistance. Crude protein, crude fibre, ash, fat, starch, sugar, amino acids, fatty acid and macroelement levels were determined by chemical analysis. In both maize lines a low level of Ca (0.15 g.kg-1 DM) and of the essential amino acids lysine and tryptophan (2.6 and 1.7 g.kg-1 DM, respectively) were observed. In the biological experiment carried out on rats the tested maize lines were the only dietary sources of nitrogen, thus, the experimental diets contained 9% CP in dietary dry matter. In the feeding experiment no significant differences in the protein efficiency ratio (PER) were observed between groups receiving conventional or transgenic maize (1.51 and 1.41, respectively). Also almost equal results were obtained in the balance experiments. Both maize lines revealed a high nitrogen digestibility (84.9 and 84.5%, respectively) and the net protein utilization amounted to 63.5 and 63.2%, respectively. From these results can be concluded that regarding nutrient composition and utilisation, genetically modified (RR) maize is equivalent to isogenic maize.     

Immunochemical approach to detection of adulteration in honey: physiologically active royal jelly protein stimulating TNF-alpha release is a regular component of honey

The presence of royal jelly (RJ) proteins in honey collected from nectars of different plants, origin, and regions and in honeybee's pollen was detected by Western-blot analysis using polyclonal antibodies raised against water-soluble RJ-proteins. The most abundant RJ-protein in honeybee products corresponded to a 55 kDa protein. The N-terminal amino acid sequence of 55 kDa protein was N-I-L-R-G-E. This sequence is identical to the apalbumin-1, the most abundant protein of RJ. Apalbumin-1 is a regular component of honeybee products and thus is a suitable marker tool for proving adulteration of honey by means of immunochemical detection. Its presence in all tested samples of honeys and honeybee pollen was confirmed also by Western-blot analysis using polyclonal antibodies raised against recombinant apalbumin-1. It has been found that major RJ-proteins, apalbumin-1, and apalbumin-2, stimulate mouse macrophages to release TNF-alpha, which demonstrates that physiologically active proteins of honey could be used for its biological valuation.     

The Nutritive Value of Lucerne Leaf Meal for Pigs Based on Digestibility and Nitrogen Utilization

Abstract

Digestibility, energy metabolism and nitrogen utilization of a barley-based diet with increasing inclusion of lucerne leaf meal (LLM; 0, 5, 10 and 20%) were studied in a change-over experiment with growing pigs. In addition, digestibility and nitrogen utilization of the diets were evaluated with rats. The apparent digestibility of fibre increased with LLM inclusion, whereas the digestibility of organic matter, crude protein, fat and energy all decreased significantly. There was a significant reduction in the dietary content of digestible and metabolizable energy with increasing inclusion of LLM in the diet. Nitrogen retention and utilization were significantly increased with an increasing inclusion of LLM.     

Automated tree detection and crown delineation using airborne laser scanner data in heterogeneous East-Central Europe forest with different species mix

Identifying tree locations is a basic step in the derivation of other tree parameters using remote sensing techniques, particularly when using airborne laser scanning. There are several techniques for identifying tree positions. In this paper, we present a raster-based method for determining tree position and delineating crown coverage. We collected data from nine research plots that supported different mixes of species. We applied a raster-based method to raster layers with six different spatial resolutions and used terrestrial measurement data as reference data. Tree identification at a spatial resolution of 1.5 m was demonstrated to be the most accurate, with an average identification ratio (IR) of 95% and average detection ratio of 68% being observed. At a higher spatial resolution of 0.5 m, IR was overestimated by more than 600%. At a lower spatial resolution of 3 m, IR was underestimated at less than 44% of terrestrial measurements. The inventory process was timed to enable evaluation of the time efficiency of automatic methods.     

Testing two Lactobacillus plantarum and Lactobacillus acidophilus strains for their suitability as a lipoid probiotic

Two strains of lactobacilli (Lactobacillus acidophilus T-135 and Lactobacillus plantarum 4/97) were selected in order to study their inhibitory properties against frequent udder pathogens (Escherichia coli, Staphylococcus aureus, Streptococcus agalactiae, Streptococcus uberis, Salmonella enteritidis and Bacillus pumilus), their production of organic acids as well as their ability to survive on the teat skin, the teat duct mucosa and in a lipoid emulsion. Both strains inhibited the tested pathogenic microbes and survived on the investigated surfaces and in an emulsion for more than 6 hours and 11 days, respectively.     

Flow cytometric analysis of bone marrow leukocytes in neonatal dogs

Dogs represent both an important veterinary species and a convenient model for allogeneic hematopoietic stem cell transplantation. Even though anti-canine CD34 antibodies have recently become available, little is known about hematopoietic lineages in dogs, partially because CD34- cells have been ignored in all analyses performed so far. In this study, we have focused on the bone marrow mononuclear compartment to provide an additional piece of information on the phenotype of CD34+ progenitors and to identify the dominant CD34- population. We have shown that, in contrast to the adults, mature lymphocytes are scarce in neonatal dog bone marrow. Using cross-reactive antibodies against CD79alpha we have shown that the B lineage of hematopoiesis strongly prevails. CD34+ cells were shown to be positive for MHC class II and SWC3, a member of the signal regulatory protein family.     

Determination of physiological dead space in anaesthetized horses: a method-comparison study

Objective

To compare two methods of Bohr–Enghoff physiological dead space to tidal volume ratio (Vd/Vt_{Bohr–Enghoff}) determination using a mixing chamber and an E-CAiOVX metabolic monitor.

Infectivity and pathogenicity of Cryptosporidium andersoni to a novel host, southern multimammate mouse (Mastomys coucha)

The infectivity and pathogenicity of Cryptosporidium andersoni (bovine isolate) for neonatal and adult southern multimammate mice (Mastomys coucha) was studied using transmission experiments. C. andersoni isolate used in this study was not infective for BALB/c mice, but experimental infection proved susceptibility of neonatal and adult M. coucha to the infection. The prepatent period was 20-24 days, the patent period varied between 46 and 59 days. No signs of clinical illness or macroscopic findings were detected in infected animals. Cryptosporidium developmental stages were detected only in the glandular part of the stomach of M. coucha in histological sections stained with Wolbach's modification of Giemsa and using immunofluorecence. Histopathological changes were characterized by dilatation and epithelial metaplasia of infected gastric glands without inflammatory response in the lamina propria. Neonatal M. coucha were more susceptible to C. andersoni infection than adults. M. coucha seems to be a useful laboratory model for study of C. andersoni infection.