116 research outputs found

    Simultaneous Determination of Nitrite and Nitrate in Milk Samples by Ion Chromatography Method and Estimation of Dietary Intake

    Get PDF
    The presence of nitrate and nitrite in foods may be considered hazardous after ingestion in the gastrointestinal tract due to their reaction with naturally occurred secondary amines to form potentially carcinogenic nitrosamines. Due to this fact, a new method was developed in this study for the simultaneous determination of nitrite and nitrate in milk samples using by ion chromatography. Proposed mobile phase composed of sodium hydrogen carbonate and sodium carbonate (1.0 and 3.2 mmol/L) with a flow rate of 0.7 ml/min. The average recoveries for nitrate and nitrite were higher than 86 and 88, respectively. The limit of detection for nitrate and nitrite were 0.24 and 0.09 mg/L, respectively. The results of 102 real milk samples showed nitrate was found in all of the samples (100) with a mean of 34 ± 11 mg/L, while nitrite was found in none of the samples. The mean intake of nitrate in all age groups was lower than World Health Organization guideline. The present assessment concludes that the maximum contaminant level was equal to 82.8 mg/L nitrate. This method was fast, sensitive and accurate and is capable of being an alternative method in food control laboratories for investigation of nitrite and nitrate content. This is the first study of the determination and survey of nitrite and nitrate and exposure assessment of the Iranian population to nitrite and nitrate level in milk, which was widely used in infants and adolescents as one of the basic food components. Copyright © Taylor & Francis Group, LLC

    Electrophysiological and molecular mechanisms of protection by iron sucrose against phosphine-induced cardiotoxicity: A time course study

    Get PDF
    The present study was designed for determining the exact mechanism of cytotoxic action of aluminum phosphide (AlP) in the presence of iron sucrose as the proposed antidote. Rats received AlP (12 mg/kg) and iron sucrose (5-30 mg/kg) in various sets and were connected to cardiovascular monitoring device. After identification of optimum doses of AlP and iron sucrose, rats taken in 18 groups received AlP (6 mg/kg) and iron sucrose (10 mg/kg), treated at six different time points, and then their hearts were surgically removed and used for evaluating a series of mitochondrial parameters, including cell lipid peroxidation, antioxidant power, mitochondrial complex activity, ADP/ATP ratio and process of apoptosis. ECG changes of AlP poisoning, including QRS, QT, P-R, ST, BP and HR were ameliorated by iron sucrose (10 mg/kg) treatment. AlP initiated its toxicity in the heart mitochondria through reducing mitochondrial complexes (II, IV and V), which was followed by increasing lipid peroxidation and the ADP/ATP ratio and declining mitochondrial membrane integrity that ultimately resulted in cell death. AlP in acute exposure (6 mg/kg) resulted in an increase in hydroxyl radicals and lipid peroxidation in a time-dependent fashion, suggesting an interaction of delivering electrons of phosphine with mitochondrial respiratory chain and oxidative stress. Iron sucrose, as an electron receiver, can compete with mitochondrial respiratory chain complexes and divert electrons to another pathway. The present findings supported the idea that iron sucrose could normalize the activity of mitochondrial electron transfer chain and cellular ATP level as vital factors for cell escaping from AlP poisoning. © 2015 Informa Healthcare USA, Inc. All rights reserved

    Comparative analysis of family values in Iranian and Russian cinema

    Get PDF
    The purpose of this study is to analyze family values in Iranian and Russian cinema. The main objective of the study is to identify key trends related to the subject of the work based on the analysis of a number of Iranian and Russian films. As a result of the study, the authors found out that in the modern cinema of these countries, we often encounter negative trends indicating the disintegration of the traditional family. The source of these trends is the negative influence of the West, and in particular, Western cinema. The relevance of this topic is determined by the fact that the family as a social institution plays an important role in the society and culture of the country. In turn, cinema as a cultural tool has an impact on the process of forming the institution of the family. In this regard, a certain repertoire policy, regulated at the highest, state level, is able to influence a certain development of the institution of the family of a particular country. The article analyzes the activities of Russia and Iran at the state level aimed at protecting their culture. The main laws and draft laws that contribute (or will contribute) to the strengthening of traditional family values in the culture of Russia and Iran in general and cinema in particular are analyzed

    Molecular and biochemical evidence on the protection of cardiomyocytes from phosphine-induced oxidative stress, mitochondrial dysfunction and apoptosis by acetyl-l-carnitine

    Get PDF
    The aim of the present study was to investigate the efficacy of acetyl-l-carnitine (ALCAR) on pathologic changes of mitochondrial respiratory chain activity, ATP production, oxidative stress, and cellular apoptosis/necrosis induced by aluminum phosphide (AlP) poisoning. The study groups included: the Sham that received almond oil only; the AlP that received oral LD50 dose of aluminum; the AC-100, AC-200, and AC-300 which received concurrent oral LD50 dose of AlP and single 100, 200, and 300mg/kg of ALCAR by intraperitoneal injection. After 24h, the rats were sacrificed; the heart and blood sample were taken for measurement of biochemical and mitochondrial factors. The results specified that ALCAR significantly attenuated the oxidative stress (elevated ROS and plasma iron levels) caused by AlP poisoning. ALCAR also increased the activity of cytochrome oxidase, which in turn amplified ATP production. Furthermore, flow cytometric assays and caspase activity indicated that ALCAR prohibited AlP-induced apoptosis in cardiomyocytes. © 2015 Elsevier B.V.

    The effects of thermal-spatial behaviours of land covers on urban heat islands in semi-arid climates

    Get PDF
    In recent decades, unsustainable urban development stemming from uncontrolled changes in land cover and the accumulation of population and activities have given rise to adverse environmental consequences, such as the formation of urban heat islands (UHIs) and changes in urban microclimates. The formation and intensity of UHIs can be influenced not only by the type of land cover, but also by other factors, such as the spatial patterns of thermal clusters (e.g., dimensions, contiguity, and integration). By emphasising the differences between semi-arid and cold-and-humid climates in terms of the thermal−spatial behaviours of various types of land cover in these climates, this paper aims to assess the behavioural patterns of thermal clusters in Tehran, Iran. To this end, the relationship between the land surface temperature (LST) and the types of land cover is first demonstrated using combined multispectral satellite images taken by Operational Land Imager (OLI), Thermal Infrared Sensor (TIRS) of the Landsat8 and MODIS, and Sentinel satellites to determine LST and land cover. The effects of different behavioural patterns of thermal clusters on the formation of daytime urban heat islands are then analysed through spatial cross-correlation analysis. Lastly, the thermal behaviours of each cluster are separately examined to reveal how their spatial patterns, such as contiguity, affect the intensity and formation of UHI, with the assumption that each point in a contiguous surface may exhibit different thermal behaviours, depending on its distance from the edge or centre. The results of this study show that the daytime UHIs do not occur in the central parts of Tehran, and instead they are created in the surrounding layer, which mostly consists of barren cover. This finding contrasts with previous research conducted regarding cities located in cold-and-humid climates. Our research also finds that the more compact the hot and cool clusters are, the more contiguous they become, which leads to an increase in UHIs. The results suggest that for every 100 pix/km2 increase, the cluster temperature increases by approximately 0.7−1 °C. Additionally, placing cool clusters near or in combination with hot clusters interrupts the effect of the hot clusters, leading to a significant temperature reduction. The paper concludes with recommendations for potential sustainable and context-based solutions to UHI problems in semi-arid climates that relate to the determination of the optimal contiguity distance and land use integration patterns for thermal clusters

    Molecular characterization of carbapenem-resistant acinetobacter baumannii isolated from pediatric burns patients in an Iranian hospital

    Get PDF
    Purpose: To survey the molecular characteristics of imipenem-resistant Acinetobacter baumannii obtained from pediatric burns patients in a teaching hospital in Tehran, Iran. Methods: Over a 10-month period, 73 non-duplicate A. baumannii strains were collected from pediatric burns patients admitted to Motahari Burn and Reconstruction Center, Tehran, Iran. The resistance profile of several antimicrobials was determined. Metallo-β-lactamase (MBL)-producing isolates were identified using double-disk synergy and an MBL E-test. Polymerase chain reaction (PCR) was carried out to detect the following β-lactamase-encoding elements: blaVIM, blaIMP, blaSIM, blaSPM, blaGIM, blaNDM, blaAIM, blaDIM, blaKPC, blaOXA-23/24/51, and blaOXA-58. The types of integrons were also identified using PCR. Results: Out of the 73 collected strains, 92.4 and 38.3 of the isolates were multidrug-resistant (MDR) and extensively drug-resistant (XDR), respectively. Colistin was the most effective antibiotic. It was found that 94.5 of the strains were resistant to imipenem, as determined both by disk agar diffusion and MIC E-test methods. Based on double disk synergy and E-test, 78.1 and 83.5 of the isolates, respectively, were MBL producers. The prevalence of blaOXA-23 and blaOXA-24 were 75.4 and 39.1 , respectively. The results also indicate that 62.3, 30.4, and 4.3 of the isolates were positive for blaVIM, blaIMP and blaNDM genes, respectively. Furthermore, 16.4, 76.1, and 7.5 of the isolates carried intI, intII, and intIII genes, respectively. Conclusion: The increased frequency of carbapenem-resistant A. baumannii in burns cases underlines the importance of choosing an appropriate antibacterial regimen based on antibiotic susceptibility profile. Rapid identification of carbapenemase-producing strains would be helpful for selecting suitable antimicrobial therapy and preventing further spread of their encoding genes. © Pharmacotherapy Group, Faculty of Pharmacy, University of Benin, Benin City, 300001 Nigeria

    Spatial variability of heavy metal concentrations in vineyard soils on Malayer Plains (Iran)

    No full text
    Accumulation of trace elements in arable soils is an important global hazard worldwide. Human activities, such as agriculture, are a continuous source of risk for heavy metal pollution that seriously disturbs the soil environment. In the present study, topsoil (0–20 cm) samples from vineyard soils in Malayer (Iran) were collected and analyzed for heavy metals, including Cu, Pb, and Zn by HR-CS FAAS. Compared with their levels in the earth's crust, these metals exhibited low concentrations. Variations in these metals were studied and geostatistics techniques were applied to generate spatial distribution maps. Empirical semivariograms can be simulated for the three heavy metals by spherical and linear models. The results of the statistical analyses (significant correlations among these metals) and their similar spatial distribution patterns indicate that Cu, Pb, and Zn probably derive from the same origin as their soil parent materials because of low levels of metals in vineyard soils. However, the high concentrations found in eastern-southern regions were probably created by anthropogenic influences, particularly application of manure and fertilizer. © 2016 Taylor & Francis
    corecore