This paper uses a mutual-information maximization paradigm to optimize the voltage levels written to cells in a Flash memory. To enable low-latency, each page of Flash memory stores only one coded bit in each Flash memory cell. For example, three-level cell (TL) Flash has three bit channels, one for each of three pages, that together determine which of eight voltage levels are written to each cell. Each Flash page is required to store the same number of data bits, but the various bits stored in the cell typically do not have to provide the same mutual information. A modified version of dynamic-assignment Blahut-Arimoto (DAB) moves the constellation points and adjusts the probability mass function for each bit channel to increase the mutual information of a worst bit channel with the goal of each bit channel providing the same mutual information. The resulting constellation provides essentially the same mutual information to each page while negligibly reducing the mutual information of the overall constellation. The optimized constellations feature points that are neither equally spaced nor equally likely. However, modern shaping techniques such as probabilistic amplitude shaping can provide coded modulations that support such constellations.

Limited knowledge exists about the effects of commonly used diuretic medications on the human normal flora. Thus, we investigated potential stimulatory effects of diuretic drug furosemide on urogenital tract microbiota in women. Three strains of E. coli and C. albicans with different biofilm forming capacities were obtained from female patients diagnosed with urinary tract infections. All tested strains were treated with two different concentrations of furosemide drug, in comparison to non-treated strains as the negative control. At specific time intervals, samples were obtained from growing culture and analyzed for their proliferation rate, aspartyl proteinase excretion and biofilm formation ability. E. coli and C. albicans strains significantly increased their aspartyl proteinase excretion under furosemide treatment. This effect was frequently observed after 16 hours of incubation at 37oC. This drug has also increased the biofilm forming capacities of E. coli and C. albicans strains. Interestingly, both E. coli and C. albicans non-biofilm former strains, gained the capacity of biofilm formation when treated with furosemide at certain concentrations. E. coli control became a weak biofilm former after 48 hours of incubation, while non-biofilm former C. albicans strain became a weak biofilm former in dose-dependent fashion, after 48 hours incubation with furosemide in concentration of 0.1 mg/mL, and after 16 hours of incubation with furosemide in concentration of 0.5 mg/mL. Loop diuretic drug furosemide is able to increase the microbial virulence and turn commensal microbes into opportunistic pathogens. Additionally, the results suggest that enzyme aspartyl proteinase might act as a signal molecule for the biofilm formation, leading to the increased microbial pathogenicity.

Heavy metals, due to their inability to degrade, pose a serious environmental and nutritional problem. The accumulation of essential and non-essential heavy metals in living organisms reduces normal growth and development, resulting in acute poisoning, disease and even death of organisms. Melatonin is a very important multifunctional molecule in protecting plants from oxidative stress due to its ability to directly neutralize reactive oxygen species (ROS). Also, melatonin has a chelating property, which may contribute in reducing metal-induced toxicity. In this paper, the protective role of melatonin in counteracting metal-induced free radical generation was highlighted. Using the HPLC-FLD technique melatonin was identified and quantified in the roots and leaves of lemon balm ( Melissa officinalis L.), grown under photoperiod conditions. Furthermore, the response of plants pre-treated with exogenous 0.1 mM melatonin to the increased zinc (Zn) and cadmium (Cd) concentrations was observed, with changes in mineral (Ca, Mg), physiological and antioxidant status of the plant during heavy metals stress. The obtained melatonin concentrations were the highest published for dry plants so far. Elevated Cd and Zn levels in soil caused alternation in biochemical and physiological parameters of lemon balm leaves and roots. However, melatonin pre-treatment increased plant tolerance to heavy metals stress. Increased Cd and Zn uptake and their translocation into the leaves were also improved, indicating the possible use of melatonin in phytoremediation.

Heavy metals disturb the redox homeostasis of the plant cell. The indolamine hormone, melatonin, protects plants from oxidative damage by directly scavenging reactive oxygen species or by stimulating the activity of antioxidant enzymes. The antioxidative role of melatonin in the leaves of two medicinal plants, lemon balm (Melissa officinalis L.) and valerian (Valeriana officinalis L.) that were treated with increased concentrations of Zn and Cd 24 h after sowing at an open field, were investigated. The plants were treated with Zn, Cd, melatonin and a mixture of melatonin with the mentioned metals. Exogenously added melatonin increased the endogenous melatonin concentration in lemon balm leaves. However, in the valerian leaves, lower or the same endogenous melatonin level was detected. The significantly higher concentration of endogenous melatonin in both plants was measured after treatment with Zn. As the results showed, changes in superoxide dismutase (SOD) and peroxidase (POD) activities are species-specific and change depending on the plant development phase, and the type of treatment. Melatonin pretreatment induced alternation in SOD isoenzyme profiles and activities as well as POD activity in both plant species treated with heavy metals.

INTRODUCTION Endothelial dysfunction is involved in the pathogenesis of insulin resistance, diabetes mellitus type 2, diabetic complications and preceded clinical manifestation of cardiovascular complications. Increased myeloperoxidase activity has been linked to a number of pathologies with compelling evidence in initiation and progression of inflammatory events. The aim of this study was to compare concentrations of metabolite nitric oxide and myeloperoxidase in the plasma of diabetes mellitus type 2 patients on metformin therapy, without clinical signs of cardiovascular disease and healthy subjects, as well as evaluation of concentrations of analytes in association with glycemic control. MATERIALS AND METHODS Forty four study subjects with diabetes mellitus type 2 and thirty healthy subjects were included in this study. The concentration of myeloperoxidase was determined by enzyme-linked immunosorbent assay, the concentration of nitrate and nitrite with high performance liquid chromatography method. Student's t test, Mann-Whitney U test, Chi-square test and Fisher's exact test were used for statistical analysis. RESULTS The mean concentration of myeloperoxidase was significantly higher in the diabetic group compared to the control group (16.2±4.9 vs. 3.7±1.8; P<0.001).The nitrite concentration was comparable in both groups while the concentration of nitrate was significantly higher in the diabetic group (41.2 [42.9] vs 31.9 [23]; P=0.017). In this study, plasma myeloperoxidase (Spearman's rho=0.421; P=0.004) and nitrate concentration was significantly positively associated with the HbA1c levels while nitrate concentration (Spearman's rho=- 0.308; P=0.047) were was significantly positively negatively associated with the HbA1c levels. CONCLUSION Concertation of MPO and nitric oxide were significantly increased in a T2DM subject even when on metformin therapy. However, increased concentration of NO strongly correlates with lower levels of HbA1c showing a postive effect of a gylcemic control on endothelial dysfuction. Increased concentrations of NO3- in T2DM subject compared to control, indicates the variety of NO pathways that should be taken into consideration win relation to endothelial function.

Black cumin (Nigella sativa L. [N.sativa]) seed extracts demonstrated numerous beneficial biological effects including, among others, antidiabetic, anticancer, immunomodulatory, antimicrobial, anti-inflammatory, antihypertensive, and antioxidant activity. To better understand the phytochemical composition of N. sativa seeds, methanol seed extracts were analyzed for phenolic acid and flavonoid content. Furthermore, we tested N. sativa methanol, n-hexane, and aqueous seed extracts for their inhibitory activity against butyrylcholinesterase (BChE) and catalase (CAT) as well as for antimicrobial activity against several bacterial and a yeast strains. The phenolic content of N. sativa was analyzed using ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). The inhibition of BChE was assessed by modified Ellman's method, and the inhibition of CAT was determined by monitoring hydrogen peroxide consumption. The extracts were tested against Bacillus subtilis, Staphylococcus aureus, Salmonella enterica, and Escherichia coli using the agar diffusion method. The UHPLC-MS/MS method allowed the identification and quantification of 23 phenolic compounds within 15 minutes. The major components found in N. sativa seed extract were sinapinic acid (7.22 ± 0.73 µg/mg) as a phenolic acid and kaempferol (11.74 ± 0.92 µg/mg) as a flavonoid. All extracts showed inhibitory activity against BChE, with methanol seed extract demonstrating the highest inhibitory activity (inhibitory concentration 50% [IC50] 79.11 ± 6.06 µg/ml). The methanol seed extract also showed strong inhibitory activity against CAT with an IC50 value of 6.61 ± 0.27 µg/ml. Finally, the methanol extract exhibited considerable inhibitory activity against the tested microbial strains. Overall, this is the first study to investigate the ability of black cumin seed extracts to inhibit CAT. Our results indicate that N. sativa seed can be considered as an effective inhibitor of CAT activity.

Recently research shows that horseradish peroxidase, HRP, when combined with other compounds, is highly reactive toward different human tumour cells and that better understanding of catalytic mechanism and inhibition HPR could lead to a new targeted cancer therapy. Thus, the inhibition of HRP activity by dipotassium-trioxohydroxytetrafluorotriborate K2[B3O3F4OH] was investigated for possible explanation of previously observed antitumour activities of this promising drug. HRP activity was studied under steady-state kinetic conditions by a spectrophotometric method. In the absence of the inhibitor values of = 0.47 mM and = 0.34 mM min−1, respectively, were determined. The hydrogen peroxide H2O2 kinetic measurements show a competitive inhibition with the inhibition constant = 2.56 mM. The activation energy values were found to be very similar for both reactions; in the absence of inhibitor activation energy was 17.7 kJ mol−1 and in the presence of inhibitor activation energy was 16.3 kJ mol−1. The values of Arrhenius constants were found to be different; = 4.635 s−1 was measured in the absence of inhibitor while in the presence of inhibitor Arrhenius constant was 1.745 s−1 showing that K2[B3O3F4OH] initiates conformational change in the structure of the HRP and subsequently reduces its activity.

Acute pancreatitis (AP) is a serious illness, defined as acute inflammation of the pancreas, which can result in damage to the surrounding tissue and other organ systems. It is considered as a set of dynamic, local and systemic pathophysiological changes, caused by sudden rush of lithic pancreatic enzymes into glandular parenchyma. AP is an inflammatory process caused by auto-digestion of pancreatic tissue due to early activation of the zymogen into the active proteolytic enzyme. The most common causes are biliary disease and alcohol abuse. Clinical presentation is predominated by severe upper abdominal pain. Depending on the disease severity, it may be associated with systemic complications and damage to distant organs. The majority of patients have multiply elevated serum concentrations of pancreatic enzymes, amylase and lipase. AP may have a variable course and prognosis, from mild to severe forms and potentially lethal disease; therefore, early assessment using different prognostic parameters is of utmost importance. Clinical signs vary from mild interstitial pancreatitis to severe pancreatitis with necrosis and associated multiple organ failure. The clinical course of mild AP is generally without complications and full recovery is expected. Treatment is conservative and/or surgical, and consists of pain control, fluid replacement, nutritional support, and prevention of complications. Key words:

Lactoperoxidase (LPO) found in saliva, tears and airways protects system against bacterial and viral attack. It utilized hydrogen peroxide in the presence of halides or pseudohalide forming hypohalous..

Lactoperoxidase (LPO) found in saliva, tears and airways protects system against bacterial and viral attack. It utilized hydrogen peroxide in the presence of halides or pseudohalide forming hypohalous acid a potent biocidal and virocidal agent. Melatonin is an important biomolecule that controls a number of functions including circadian sleep rhythms, blood pressure, oncogenesis, retinal function, seasonal reproduction, and immunity. Additionally, melatonin is frequently used as a supplement in a variety of medical conditions such as jet lag, shift work, and circadian rhythm sleep disorders, cancer, longevity and antioxidant therapy. Here, we demonstrate that melatonin modulates classic catalytic mechanism of LPO under physiological-like conditions. In the presence of chloride (SCN-), melatonin inactivated LPO classic peroxidase cycle by formation of compound II or two different intermediate compounds that are “dead end” products of LPO system. This behavior indicates that melatonin modulates the formation of LPO intermediates and their decay rates to the ground state this efficiently slowing down or inhibiting the cycling of the enzyme. Importantly, melatonin-dependent inhibition of LPO depends on hydrogen peroxide concentrations. Thus, the interplay between LPO and melatonin can have a broader implication especially in the cases of supplemental melatonin therapy.

Globalization as a worldwide process has significant implications in the area of education. In relation to this trend, the main challenge is to prepare students for the role of competent global citizens. Thus, we tested selected group of students of chemistry in attempt to measure their understanding of global trends in education. Results show positive attitudes towards student mobility, but no vision to develop competence and capacity that will make them quality applicants for international mobility programs. Scarce examples of students engagement in global educational trends only magnifies the need for well researched and organized approach in this area.