The evidence for histamine H3 receptor-mediated endothelium-dependent relaxation in isolated rat aorta

The presence of histamine H3 receptors was evaluated on the rat aorta endothelium. In the presence of pyrilamine (1 nM, 7 nM, 10 nM) or thioperamide (1 nM, 10 nM, 30 nM) the concentration–response curve for histamine-induced (0.1 nM − 0.01 mM) endothelium-dependent rat aorta relaxation was shifted to the right without significant change of the Emax indicating competitive antagonism by pyrilamine (pA2 = 9.33 ± 0.34, slope = 1.09 ± 0.36) or thioperamide (pA2 =9.31 ± 0.16, slope=0.94 ± 0.10). Cimetidine (1 μM) did not influence histamine-induced endothelium-dependent rat aorta relaxation. In the presence of thioperamide (1 nM, 10 nM, 30 nM) the concentration–response curve for (R)α-MeHA-induced (0.1 nM − 0.01 mM) endothelium-dependent relaxation was shifted to the right without significant change of Emax indicated competitive antagonism by thioperamide (pA2 = 9.21 ± 0.4, slope = 1.03 ± 0.35). Pyrilamine (100 nM) or cimetidine (1 μM) did not influence (R)α-MeHA-induced endothelium-dependent rat aorta relaxation. These results suggest the presence of a heterogenous population of histamine receptors, H1 and H3, on rat aorta endothelium

Management of Women — Risk or Opportunity?

A lot has been written about women. Throughout human civilization women have been the foundation of families, but also wars were waged over women, and through marriages friendships were created or expanded, agreements forged between friends, etc. Even today women are the entity, without which one can not imagine the existence of the universe. In other words, evolution is a process in which cells (male and female) are connected resulting in growth and development, but also in the ability to connect with other cells which leads to the formation of living beings, including man as the most complex living being which operates on the principles of selforganization. However, when it comes to politics, business and the general performance of complex and traditional activities that are practiced by men, women are marginalized and discriminated against on numerous issues. Stereotypes and negative attitudes toward business women or women managers have been carefully maintained over centuries. Not far from the truth is statement according to which women must be twice as good as men, to take up important positions in organizations. The aim of this paper is to point out certain indisputable facts when it comes to female management and to answer the question of whether female management is a risk or a chance

Endothelium-dependent relaxation of rat aorta to a histamine H3 agonist is reduced by inhibitors of nitric oxide synthase, guanylate cyclase and Na+,K+-ATPase

The possible involvement of different effector systems (nitric oxide synthase, guanylate cyclase, β-adrenergic and muscarinic cholinergic receptors, cyclooxygenase and lipoxygenase, and Na+,K+-ATPase) was evaluated in a histamine H3 receptor agonist-induced ((R)α-methylhistamine, (R)α-MeHA) endothelium-dependent rat aorta relaxation assay. (R)α-MeHA (0.1 nM – 0.01 mM) relaxed endothelium-dependent rat aorta, with a pD2 value of 8.22 ± 0.06, compared with a pD2 value of 7.98 ± 0.02 caused by histamine (50% and 70% relaxation, respectively). The effect of (R)α-MeHA (0.1 nM – 0.01 mM) was competitively antagonized by thioperamide (1, 10 and 30 nM) (pA2 = 9.21 ± 0.40; slope = 1.03 ± 0.35) but it was unaffected by pyrilamine (100 nM), cimetidine (1 μM), atropine (10 μM), propranolol (1 μM), indomethacin (10 μM) or nordthydroguaiaretic acid (0.1 mM). Inhibitors of nitric oxide synthase, L-NG-monomethylarginine (L-NMMA, 10 μM) and NG-nitro-L-arginine methylester (L-NOARG, 10 μM) inhibited the relaxation effect of (R)α-MeHA, by approximately 52% and 70%, respectively). This inhibitory effect of L-NMMA was partially reversed by L-arginine (10 μM). Methylene blue (10 μM) and ouabain (10 μM) inhibited relaxation (R)α-MeHA-induced by approximately 50% and 90%, respectively. The products of cyclooxygenase and lipoxygenase are not involved in (R)α-MeHA-induced endothelium-dependent rat aorta relaxation nor are the muscarinic cholinergic and β-adrenergic receptors. The results also suggest the involvement of NO synthase, guanylate cyclase and Na+,K+-ATPase in (R)α-MeHA-induced endothelium-dependent rat aorta relaxation

Biosorptive removal of Pb2+, Cd2+ and Zn2+ ions from water by agenaria vulgaris shell

Lagenaria vulgaris (LV) shell was used as a biosorbent for the removal of heavy metal ions, Pb2+, Cd2+ and Zn2+, from aqueous solutions. Experiments were carried out under batch conditions. The effects of contact time, initial pH, temperature and stirring speed on removal efficiency are presented. Sorption of the investigated metals was fast, reaching equilibrium after about 5 to 10 min, depending on the metal. Biosorption was highly pH-dependent, and the optimal pH for investigated metals was in the range of 4.5 to 6.0. The effects of temperature demonstrated that biosorption of the metals is a chemical process. SEM analysis revealed interesting morphological changes after acid refinement of the raw biosorbent and metal uptake that is related to the chemical nature of the biosorption process. EDX analysis of Lagenaria vulgaris biosorbent(LVB) before and after metal sorption revealed that the ion exchange mechanism was the principal sorption process. Fourier transform infrared spectroscopy (FTIR) analysis has shown that major functional groups (carboxyl and hydroxyl) on the biosorbent surface took part in the metal ion uptake process as active sites. The results obtained showed that Lagenaria vulgaris based biosorbent could be used as an effective and low-cost pre-treatment step for removal of toxic metals from wastewaters

The Energy Value and Energy Yields of Alfalfa Forage Depending on the Cutting Time in Forage-Seed Production System

Economic importance of alfalfa (Medicago sativa L.) is reflected in the production of high-quality forage, however, the seeds of alfalfa are valuable commodity in the domestic and international markets. In Serbia, the seed is produced in forage-seed mode of exploitation where the second or third growth is used for seed production, and the remaining growths are used for fodder. The aim of this work was to determine the influence of cuttings and time of cutting on total energy value of hay in a model of forage and seed production. The second and third cuts were used as seed cut. In the variant where the second cut was used as seed cut, the first cut was harvested at different times (A1-early, A2-medium early, A3-late and A4- very late). In the model where the third cut was used for seed, two pre-cuts were used for forage production (A5). In all the following variants, seed cut was followed by one more cutting (final cut), used for the production of fodder. The highest average total production (from pre-cut and final cut) of NEL (34606 MJha-1) and NEM (33811 MJha-1) was realized in the system of cutting with two pre-cuts. In the variant with single pre-cut, the highest yield was formed in the early system. Later cutting of the first cut causes decline of NEL production and it was the lowest in the system of very late cutting or 15.1 % less than in the early system and 38% lower than in the system of cutting with two pre-cuts. Delaying of utilization of alfalfa to the later stages of exploitation has contributed to the lower yield of NEM and in the medium early system and late system and especially in the very late cutting system, where by 22.2 % less was realized than in the early production system. Studies have shown that late cutting of first cut resulted in the reduction of nutritional value expressed in the amount of net energy per unit area

Bacterial iron-oxide nanowires from biofilm waste as a new adsorbent for the removal of arsenic from water

Biofilm, generated by the bacteria in the groundwater pumping system pipelines of the Salt Interception Scheme on the River Murray in South Australia is discarded as a waste material accumulated after periodic cleaning of the pipes. Structural and chemical composition characterizations confirm that this waste material is composed of amorphous twisted iron-oxide nanowires (ION), generated by bacteria, and they have a unique structure and properties. The adsorption performance of these iron-oxide nanowires for arsenic removal from water was evaluated to define their adsorption capacity for As(III) and As(V) and kinetics. Obtained results demonstrate considerable adsorption properties of this waste biological material and suggest its promising application as a new and low-cost adsorbent for water treatment.Ivan Andjelkovic, Sara Azari, Mason Erkelens, Peter Forward, Martin F. Lambert and Dusan Losi

The Effect of Addition of Lucerne Biomass and NPN Substances on Quality of Grape Pomace Silage

Grape pomace (GP) of white varieties without stalks was ensiled by the method of single factor trial in the two treatments: in the first treatment, with the addition of lucerne biomass (L) of the last cut, which was harvested at the stage of forming pods with equal shares in the weight ratio and in the second with the addition of Benural S (B) in the amount of 1%. Chemical analyses were conducted on GP and L to determine the suitability of biomass for silage and to determine the chemical composition and nutritional value and the process of lactic acid fermentation. It has been found that the biomass of GP had 2 times higher concentration of water-soluble carbohydrates (WSC 140.5:69.4 gkg-1DM) relative to L, and a lower buffer capacity (BC) what makes it 10 times more favourable for ensiling (ratio WSC/BC 13.1 : 1.3). GP, as compared to L, had lower contents of CP, CF, and a lower nutritional value expressed in NEL and NEM units and a higher content of crude fat. Silage with the equal share of GP + L compared to silage with GP + B had a slightly lower CF and significantly less crude fat and ash, especially Ca. More favourable ratio Ca : P (2.93 : 1) was established in silage GP + L compared to 10.1:1 silage GP + B. Silages GP + L in the fermentation process were scored/rated one class higher according to the DLG and Zelter assessment methods, compared to the silages GP + B. The aim of the study was to investigate the possibility of ensiling grape pomace with equal proportion of biomass of lucerne and added NPN substances and to determine the detailed chemical composition, nutritive value and silage quality on the basis of the process of lactic acid fermentation

Effect of Consecutive Cut and Vegetation Stage on Cncps Protein Fractions in Alfalfa (Medicago Sativa L.)

Crude protein (CP) of forages can be separated into fractions of differentiated abilities to provide available amino acids in the lower gut of ruminants. This knowledge is critical to develop feeding systems and to predict animal responses. The objective of this research was to asses whether CP concentrations and the relative proportion of CP fractions by CNCPS in alfalfa (Medicago sativa L.) cv K-28 were affected by different cuts and vegetation stages. Fraction B2, which represents true protein of intermediate ruminal degradation rate, was the largest single fraction in all cuts except in the third cut. Soluble fraction A was less than 400 g kg-1 CP in all cuts except in the third cut, while the unavailable fraction C ranged from 56 g kg-1 CP in the first cut to 134.8 g kg-1 CP in the fourth cut. The remaining fraction B3 (true protein of very low degradation rate) only represented less than 60 g kg-1 of total CP. Results showed that undegraded dietary protein represented a small proportion of total CP in alfalfa from the first to the fourth cut