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The study included the estimation of some heavy metals toxicity and oxidation of erythrocytes. As the effect can be arranged elements: Fe > Cu > Ni > Mn > Mg. The effect of Fe and Cu increases absorbance due to hemolysis. Evaluated at a concentration of that caused % hemolysis, the combination of Fe: Ni had the highest model deviation ration (MDR) of 0.859 indicating an additive toxic effect. An antagonistic effect was observed for three models metal combination of with the strongest effect found, with a MDR of 0.245, for Fe: Cu: Ni. In the study of the effect of vitamins (C and B2) on % hemolysis of erythrocytes pollution of with heavy metal were tested and the results, we conclude that the effect of Vit. (C and B2) on % hemolysis of erythrocytes, at a low concentration when treated with (Fe, Cu and Ni), leads to an increase reduction in the rate % hemolysis and lower % hemolysis, but increasing the concentration of Vit (C and B2), leads to a lesser reduction of % hemolysis. [ABSTRACT FROM AUTHOR]

The 1:1 molecular complexes of triterpene glycoside glycyram (monoammonium salt of glycyrrhizic acid, GC) with amino acids arginine (Arg) and glycine (Gly) were obtained in the liquid phase. The complex formation was first studied by ATR IR-Fourier spectroscopy. It was shown that H-bonds are formed between the components of the complex GC with Arg. Ionic interactions of GC with Arg and Gly molecules are possible. GC and its molecular complexes with Arg and Gly did not cause in vitro hemolysis. [ABSTRACT FROM AUTHOR]

A series of styrene and α-methyl styrene copolymers were synthesized on the basis of their various derivatives. The hemolytic effect of polymer films was determined in vitro. The influence of polymer particle suspension on human erythrocyte hemolysis, as well as the effect of polymer films on human blood cells, has been established. The data obtained indicate that they are completely hemocompatible. [ABSTRACT FROM AUTHOR]

The process of hemolysis of erythrocyte suspension induced by hydrochloric acid (HCl) is investigated by measuring the UV-Vis absorption spectrum in the range 250 nm - 750 nm at interval 1 nm. The spectrum is measured each 15 s to the end of hemolysis. The methods of Multiplicative Scatter Correction (MSC) and Principal Component Analysis (PCA) were applied for analysis of spectra. Multiplicative Scatter Correction of spectra allowed removing effects of scattering and observing the changes related to the hemoglobin absorption in the course of hemolysis - shift of Soret band from 420 to 412 nm, decreasing of two peaks of oxyhemoglobin at 543 and 577 nm and disappearing of globin-hem interaction band at 344 nm. The Principal components of transformed spectra were more informative compared to Principal components of raw spectra and contained features related to absorption of hemoglobin. [ABSTRACT FROM AUTHOR]

The copolymers of N-methyl-2-azanorbornene-5 (MAN), N-benzyl-2-azanorbornene-5 (BAN), N-allyl-2- azanorbornene-5 (AAN) and N-(2-azanorbornene-5)methylacetate (MAAN) with N-vinylpyrrolidone (VP) have been obtained by free radical polymerization. New copolymers were evaluated for their antioxidant properties in lipid peroxidation induced by iron/ascorbate and in erythrocyte hemolysis by H2O2. The copolymer of BAN-VP has found to inhibit lipid peroxidation in liver homogenate. [ABSTRACT FROM AUTHOR]

The process of hemolysis of erythrocyte suspension induced by thioridazine (TDZ) was investigated by measuring the UV-Vis absorbance spectrum in the range 200 nm - 700 nm. The time needed to obtain the spectrum in this range was 12.5 s, so the spectrum was measured each 15 s. This permitted to follow the changes in absorbance at different wavelengths of the spectra during hemolysis. It was found that at most of the wavelengths measured the absorbance decreased which was related to the decrease of the light-scattering by the intact erythrocytes. In contrast, the absorbance peak of the hemoglobin (Hb) at 416 nm increased significantly during hemolysis. This was attributed to smaller light absorption by Hb when the erythrocytes were still intact and the Hb is still inside the erythrocytes. This phenomenon was due to the forward-scattered light that did not penetrate the erythrocytes and did not interact with Hb. When Hb was released from erythrocytes it could already interact with the light, resulting in increase of the absorption peaks of Hb and especially of the peak at 416 nm. The kinetics of the decrease of light-scattering at 700 nm and 500 nm and the increase of Hb absorption at 416 nm were compared and it was found that they are directly related. The kinetics of hemolysis induced by different concentrations of TDZ were measured. It was found that the time for hemolysis depended on the TDZ concentration as power function with power factor of minus 5. [ABSTRACT FROM AUTHOR]

Edwardsiellosis, caused by Edwardsiella tarda, appeared in catfish farms and caused mass mortality. The morphology of catfish in Edwardsiellosis resembles the disease of Aeromonas hydrophila but with haemolysis. Catfish samples with Edwardsiellosis morphology were taken from a catfish pond in the Singosari district, East Java. Isolation and identification of Edwardsiella tarda bacteria was tested by morphology, biochemistry, and molecular identity. The clinical symptoms of Edwardsiellosis included a white wound in the head of the Clarias and a red swelling near the pelvic fin. A bacterial biochemistry test showed positive in the production of indole, H2S in triple sugar iron agar, citrate, malonate reduction and motile, and neither production of acid from D-mannitol, sucrose, trehalose, L-arabinose nor malonate utilization. This bacterium showed positive for β haemolysis. From the 16S rRNA, determined with software phylogeny FR and BLAST, a genetic relationship between Edwardsiella and Aeromonas was shown. Using a form of FASTA from Edwardsiella sp., this bacterium showed an 82% genetic relationship with Edwardsiella tarda ATCC15947. The LD50 of this bacterium was 107 cfu/ml. [ABSTRACT FROM AUTHOR]

Nano-sized magnesium oxide (MgO) has been a promising potential material for biomedical pharmaceuticals. In the present investigation, MgO nanoparticles synthesized through in-situ solid-phase transformation based on the previous work (nano-Mg(OH)2 prepared by precipitation technique) using magnesium nitrate and sodium hydroxide. The phase structure and morphology of the MgO nanoparticles are characterized by X-ray powder diffraction (XRD), selected area electronic diffraction (SAED) and transmission electron microscopy (TEM) respectively. In vitro hemolysis tests are adopted to evaluate the toxicity of the synthesized nano-MgO. The results evident that nano-MgO with lower concentration is slightly hemolytic, and with concentration increasing nano-MgO exhibit dose-responsive hemolysis. [ABSTRACT FROM AUTHOR]

Traditional medicine is largely used to sustain global health requirements. Determining the biological activities of Solenostemon monostachyus is essential to provide a platform for treating hemolytic diseases. The methanolic extract of the leaves was orally administered for 5 days at 150 mg/kg, 200 mg/kg and 250 mg/kg of body weight doses to determine concentration of tumor necrosis factor-alpha (TNF-α), and the activities of the heme oxygenase-1 (HO-1) and cyclooxygenase 2 (COX-2) of plasma in the kidney, spleen and liver of 2-butoxyethanol hemolytic-induced rats. A dose of 150 mg of extract/kg of body weight significantly increased (p<0.05) HO-1 in the kidney. COX-2 activity was significantly reduced (p<0.05) mainly in the kidney untreated hemolytic induced rats. All treatments significantly increased (p<0.05) TNF-α concentrations in the kidney and spleen. HO-1 gene expression was downregulated, indicating stress reduction in the liver, by an extract dose of 200 mg/kg of body weight and caffeic acid and was upregulated, indicating stress in the spleen, by an extract dose of 150–200 mg/kg of body weight. A dose of 200–250 mg of extract/kg of body weight resulted in relatively good anti-inflammatory properties, and may possess healing properties in patients with hemolytic related diseases. [ABSTRACT FROM AUTHOR]

Nosocomial infections have an important place in human pathology, becoming a major public health problem due to the high frequency of multiresistant strains, with afferent consequences. In the Intensive Care Units (ICU), nosocomial infections represent a constant risk due to a cumulus of factors that increase susceptibility to infections, respectively: decreased immunity due to underlying pathology, patient exposure to a series of invasive manoeuvres, poor nutritional status etc. The purpose of this study was to establish the virulence profiles of nosocomial bacterial strains isolated from localized and systemic infections in immunocompromised patients. In our study, we investigated a total of 108 samples (throat swabs, wound secretions, tracheal secretions, urine and blood), collected from patients hospitalized in 2017, both in the ICU and in other clinical departments of the Emergency Institute of Cardiovascular Diseases "Prof. CC. Iliescu". After isolation on selective culture media, the bacterial strains were identified using the VITEK II system and the antibiotic susceptibility spectrum were established according to CLSI 2017/EUCAST 2017 recommendations. The production of extracellular hydrolytic enzymes was determined by using specific growth media. The results were recorded semi-quantitatively and expressed as the ratio of the colony diameter to the diameter of the colony plus the precipitation/haemolysis zone. The bacterial invasiveness ability and adherence to HeLa cells were assessed by Cravioto's adapted qualitative and quantitative methods. Adherence indexes and patterns were established by microscopic evaluation. The invasive capacity was evaluated using a quantitative assay of the colony forming units- CFU/ml. Our results indicate that the most common etiological agents of nosocomial infections are multiple drug-resistant (MDR) opportunistic bacteria identified as Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter baumanii. The MDR+ and MDR- strains were identified by conventional biochemical assays and analysed for their ability to produce soluble virulence factors (enzymes) and cell associated that are involved in bacterial cell adhesion. Our research revealed that source of isolation of the total 108 analysed strains expressed an aggregative diffusion pattern. Also, the mean values of adhesion and invasion in the MDR group were significantly higher than those observed in the non-MDR group. [ABSTRACT FROM AUTHOR]

As biodegradable biomaterials, magnesium alloys have favorable physical, chemical and mechanical properties, as well as good biocompatibility, and are expected to totally biodegrade in the body environment. The microstructure mechanical properties, corrosion behaviors and hemolysis of biodegradable Mg-Sn-Zn alloy were investigated under three extrusion ratios in the present work. It is revealed that the as-extruded microstructure is obviously refined with smaller grains compared with the as-cast structure while some twins form simultaneously. The tensile strengths of the as-extruded alloys fabricated with the higher extrusion ratio is 249MPa, and elongations is 16.3% respectively. Besides, the corrosion rate of as-extruded magnesium alloys increases with the increasing extrusion ratio. The hemolysis test result shows that the hemolysis rate of biodegradable magnesium alloys fabricated with the higher extrusion ratio is 4.8%, when hemolysis rate lower than 5% has been demonstrated safe according to ISO 10993-4. In conclusion, the as-extruded biodegradable Mg-Sn-Zn alloy shows great potential as a novel medical implant material. [ABSTRACT FROM AUTHOR]

The aim of the study was to explore the possibility of further use of pectin biopolymers obtained by the authors as a component of preparations, which can remove from the body toxic metals, and drugs that can replace blood plasma. To accomplish this goal were used research methods complexing properties of pectin biopolymers with respect to toxic metals (for example, lead); methods of studying the influence of pectin solutions on resistance of red blood cells in laboratory animals (rabbits) when changing the osmotic pressure and the presence of the hemolytic agent in the system in vitro. Pectin biopolymers obtained from waste plants (pomace) on the methodology developed by the authors. Research has shown that pectin biopolymer had a low molecular weight (7683), pH value is close to indicators whole blood of laboratory animals and humans (7.21). During the investigation, a protective effect of 1% aqueous pectin solutions on the erythrocyte membrane it has been found. The protective effect manifested by a decline activity of the acid hemolysis. The ability to bind the lead ions in the obtained pectin was quite high. For example, one gram of obtained pectin could bind 394.65 mg of lead. Commercial pectin could bind 180.71 mg of lead, under the same experimental conditions. It is possible to draw conclusions that the obtained pectin may use in the development of drugs and functional foods that reduce the toxic load on the body, which is important in ecologically unfavorable areas. In addition, these biopolymers is possible to study with the aim of developing solutions that can replace blood plasma at intoxication of an organism. [ABSTRACT FROM AUTHOR]

Ultrasound activated contrast agents inside microvessels induce mechanical effects on the vessel wall. It is important to use the bubbles safely and avoid rupturing the vessels. The objective of this work was to develop a three dimensional model of a bubble, blood and microvessels in order to investigate the mechanical effects (mainly the fluid shear stress and the circumferential stress) by a non-inertial microbubble on the vessel wall. A finite element method was used to solve for this model numerically. The blood vessel was simulated as having a viscoelastic, elastic or a rigid wall. Acoustic pressure and frequency were varied and the values for fluid shear stress and circumferential stress on the vessel wall were calculated. The circumferential stress could exceed the vascular strength in rigid microvessels if the applied acoustic pressure is above 260 kPa. Also the values for fluid shear stress are large enough to induce hemolysis or damage the cell membrane close to the oscillating bubble. Next, the streamlines and stagnation points are obtained for a rigid and a flexible vessel. [ABSTRACT FROM AUTHOR]

The blood is one of the corporal fluids more used with analytical purposes. When the blood is extracted, immediately it is affected by agents that act on it, producing transformations in its elements. Among the effects of these transformations the hemolysis phenomenon stands out, which consists of the membrane rupture and possible death of the red blood cells. The main purpose of this investigation was the quantification of this phenomenon. A Solartron SI-1260 Impedance Spectrometer was used, which covers a frequency range of work from 1 μHz to 10 MHz, and its accuracy has been tested in the accomplishment of several applications. Measurements were performed on 3 mL human blood samples, from healthy donors. Reactive strips for sugar test of 2 μL, from Bayer, were used as electrodes, which allow gathering a portion of the sample, to be analyzed by the spectrometer. Preliminary results of these measurements are presented. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

We have recently developed a genetically and chemically-modified α-haemolysin pore for the simultaneous measurement of a range of neurotransmitters, including purines, catecholamines and glutamate (Boersma et al., 2012). Building upon a previous purine-sensitive pore (Cheley et al., 2002), a catecholamine binding side that incorporated Cu2+ allowed several catecholamines, including noradrenaline, adrenaline and dopamine, to bind. These measurements were made in a Cl--free, HCO3--free physiological saline containing (mM): 118 NaCl, 10 MOPS, 4.7 KCl, 1.8 CaCl2, 1.8 MgCl2, 11.1 D-glucose; pH 7.4. When such pores are incorporated into an artificial bilipid membrane, and then voltage-clamped, single molecules of these neurotransmitters can be detected as they block the α-haemolysin pore. The identity of each molecule can be determined my measuring both the amplitude of the conductance block and the dwell time of the molecule on the pore. We have demonstrated the ability of this technique to distinguish separate molecules in a cocktail of ATP (5 µM), ADP (5 µM) and noradrenaline (1 µM), and describe a technique for calculating the concentration of each component of the mixture. Glutamate (<5 µM) is also detectable with the same pore. Altering the clamp voltage modifies the relative sensitivity of the pore, which provides an additional method for identifying binding molecules. Such a need might arise if very similar species need to be distinguished. We have tested this probe on the spontaneous and epibatidine-evoked release of transmitters from PC12 cells, and in pilot experiments can simultaneously identify ADP, ATP and noradrenaline, as well as a small set of other binding events for which the chemical species responsible have not yet been identified. The stable nature of α-haemolysin implies that this approach may be developed to produce a relatively simple-to-use method for single-molecule detection of neurotransmitter release in small sample volumes, although several technical challenges remain including the optimization of suitable bilipid membranes (or other methods of supporting the channel), reducing the binding site affinity (to increase the off rate and hence increase the sampling frequency, particularly for catecholamines) and the identification of all biologically relevant binding molecules. [ABSTRACT FROM AUTHOR]