Effects of mill stream flours technological quality on fermentative activity of baker's yeast Saccharomyces cerevisiae

This work in concerned with the interdependence between technological quality of mill stream flours and fermentative activity of baker's yeast Saccharomyces cerevisiae. Each mill stream flour has its own specific properties, determined by the particle size, technological phase of its formation and part of the wheat kernel it consists of. Biochemical complexity of dough during examination of fermentative activity of baker's yeast confirmed the influence of a number of physical and biochemical flour properties, such as ash content, wet gluten content, rheological flour properties, phytic acid content and amylograph peak viscosity. Abudance of significant flour characteristic, their interaction and different behavior in the presence of the yeast, showed diversity and variation of result within the same category of the mill stream flour

Ellipsometric measurements of plastically deformed copper

Chemically pure copper (99.99) prepared in the sample of square cross-section (10 x 10 mm2) and length about 50 mm was extremely plastically deformed with the repeated application of equal channel angular pressing. Equal channel angular pressing was applied as an effective technique for producing bulk nanoscaled structures. It is well known that severe plastic deformation of metallic materials often leads to microstructure with ultrafine grains and cross-sections which remain about equal before and after deformation. Optical properties of the sample were studied using spectroscopic ellipsometry in UV-VIS range. The parameters of the sample like copper oxide and surface roughness overlayer were calculated using two-film model together with the Bruggeman effective medium approximation

Optical properties of plastically deformed copper

Pure copper (99.99), prepared in the sample of square cross-section (10 x 10 mm2) and length about 50 mm, was extremely plastically deformed with the repeated application of Equal Channel Angular Pressing (ECAP). ECAP was applied as an effective technique for producing bulk nano-scaled structures. Optical properties of the sample were investigated using Raman spectroscopy. Two types of lines: narrow (with width of 7 cm¡1) and wide ( 40 cm¡1) are registered. Existence of two types of lines indicates that in the specimen exists nano-sized crystal structures of both Cu and CuO related with three dimensional amorphous boundary spaces, which indicates that plastic deformation of the sample did not lead to total amorphisation of the specimen

L-arginine reduces tubular cell injury in acute post-ischaemic renal failure

Background. The pathophysiology of renal ischaemia, resulting in tubular cell injury and leading to acute renal failure (ARF), remains unclear. An ever-increasing number of investigations focus on a possible role of nitric oxide (NO) in regulating circulation during ARF. In this context, we investigated the influence of chronic stimulation or inhibition of NO synthesis, or both, on haemodynamic parameters, histology and plasma renin activity (PRA) after ischaemia-reperfusion injury of rat kidneys. Methods, Experiments were performed on adult, male Wistar rats. Before induction of ARF, a group of animals was treated with a NO synthesis inhibitor (L-NAME) and another group was treated with a precursor of NO synthesis (L-arginine). The animals received those substances for 4 weeks. Control groups received the same amount of tap water for 4 or 8 weeks and were divided into groups with ARF (4 weeks-ARF group and 8 weeks-ARF group) and a sham-operated group. Another group of rats was treated first with L-NAME and then with L-arginine in their drinking water, for 4 weeks for each of these two substances. All parameters were evaluated 24 h after the induction of ischaemic ARF or the sham operation. Results, Our results show that such long-term stimulation of NO release by L-arginine improved renal haemodynamics in the ischaemic form of ARF. Renal blood Bow (RBF) increased by 96% in the L-arginine-treated rats with ARF compared with the group with ARF alone. Inhibition of NO synthesis worsens renal haemodynamics after ARF. However, this aggravation can be reversed by L-arginine. The rate of water reabsorption was reduced in all groups with ARF, but this reduction was least in the group treated with L-arginine. The rate of Na+ reabsorption was reduced in all groups 24 h after renal ischaemia, but a significant decrease was observed after the inhibition of NO synthesis. Histological examination of the kidney specimens showed that morphological changes were least in the rats treated with L-arginine, when compared with all other groups with ARF. Nevertheless, the lesions were most prominent in the L-NAME + ARF group. In this group, the areas of corticomedullar necrosis were more widespread in comparison with other groups, especially the L-arginine group where only swelling of the proximal tubular cells was observed. Treatment with L-NAME was not accompanied by any significant alteration in the plasma concentration of angiotensin I (ANG I), while in the group treated with L-arginine ANG I had a tendency to decrease. Conclusions. Acute post-ischaemic renal failure may be alleviated by administering the NO substrate (L-arginine). NO acts cytoprotectively on tubular epithelial cells in ischaemia-reperfusion injury of rat kidney. Evidence of this comes from both histopathological findings and increased tubular water and sodium reabsorption. However, inhibition of NO synthesis (provoked by L-NAME) worsens renal haemodynamics and aggravates morphological changes after ARF. These aggravations can, however, be reversed by L-arginine

Serum myeloperoxidase chlorinating activity in acute ischemic stroke

Beyond traditional risk factors, inflammation is believed to play a role in the development of ischemic stroke (IS). During inflammation neutrophil leukocytes degranulate, thereby releasing the enzyme myeloperoxidase (MPO) into extracellular space. In addition to peroxidase activity, MPO expresses also a chlorinating activity, and catalyzes the formation of hypochlorous acid and long-lived oxidants - chloramines. In this study we assessed serum chlorinating MPO activity and concentration of total chloramines. We included 29 patients with acute IS, aged 69.0 years (64.2 - 78.0) and 25 control subjects without IS, aged 69.0 years (67.0 - 72.0). It was found that neutrophil cell count was higher in IS than in controls (4.56 ± 1.76 vs. 7.74 ± 3.35 × 109/L, in control and IS group, respectively; p< 0.05). Serum chlorinating MPO activity was also higher in IS group than in controls (67.2 U/L vs. 92.3 U/L, in controls and in patients, respectively; p < 0.05). Concentration of total chloramines was higher in IS group than in controls, but the difference did not reach statistical significance (p=0.178). MPO activity was significantly correlated with serum triglycerides (p<0.05). There was no statistically significant correlation between chlorinating MPO activity and chloramines (p=0.402), while correlations between MPO activity and neutrophil cell count (p=0.071), and MPO activity and the presence of arrhythmia (p=0.094) were both of borderline significance. These results indicate that MPO may be implicated in pathogenesis of IMU, which could be partly due to chlorination of biologically important molecules within vascular compartment

Ellipsometric Measurements of Plastically Deformed Copper

Chemically pure copper (99.99) prepared in the sample of square cross-section (10×10 $mm^{2}$) and length about 50 mm was extremely plastically deformed with the repeated application of equal channel angular pressing. Equal channel angular pressing was applied as an effective technique for producing bulk nanoscaled structures. It is well known that severe plastic deformation of metallic materials often leads to microstructure with ultrafine grains and cross-sections which remain about equal before and after deformation. Optical properties of the sample were studied using spectroscopic ellipsometry in UV-VIS range. The parameters of the sample like copper oxide and surface roughness overlayer were calculated using two-film model together with the Bruggeman effective medium approximation