235 research outputs found

    Effect of moisture levels on the oxidation of unsaturated fats

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    The subject of investigation is the effect of moisture levels on the catalysed oxidation of unsaturated fats in meals and in model systems using a starch matrix. Initially the effect of moisture levels and other factors on lipoxidase catalysed oxidation of linoleate and soya bean oil is described. In most of these studies soya beans were used as a source for lipoxidase, although other sources were examined. The effect of moisture levels on haematin compounds catalysed fat oxidation was investigated. In most studies haemoglobin was used as a catalyst although other haematin compounds have been examined. In addition the effect of moisture level on the action of the enzyme lipoxidase has been compared with results for the haemoglobin. In this study, a model systems were used, since they provided for closer control for the variables than would be possible with normal foodstuff. Fresh foods are known to contain natural substances which protect them from rapid deterioration, the antioxidants. There are also substances likely to promote oxidative deterioration, among the haematin compounds and lipoxidase, the importance of which, in influencing stability of food fats has been the subject of much speculation. The results of these studies indicate the possible implication of haematins in the oxidation deterioration of lipids in foodstuffs even when these are very dry

    Performing Interactively A Thermo-Fluids Laboratory Experiment in the Virtual Domain

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    This paper deals with the development of an experiment in the virtual domain for the undergraduate thermo-fluids laboratory in the mechanical engineering program. A physical experiment titled Venturimeter as a Flow Measuring Device is replicated as a computer-based experiment as part of the ongoing effort at Old Dominion University to develop web-based laboratories that would provide students hands-on experience in the virtual domain. A web-based module is developed that allows experimentation and data taking in a virtual setting much like in the physical experiment. This module incorporating the virtual venturimeter has been used by students to take data for several flow rates to determine the coefficient of venturimeter as a function of Reynolds number. The proposed virtual module will provide impetus for development of virtual engineering laboratories which in turn may make it possible offering of web-based undergraduate engineering programs at Old Dominion University

    Bioactivities of Traditional Medicinal Plants in Alexandria

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    In traditional folklore, medicinal herbs play a vital role in the prevention and treatment of microbial diseases. In the present study, the phenolic profiles of the medicinal plants Asparagus aethiopicus L., Citrullus colocynthis L., Senna alexandrina L., Kalanchoe delagoensis L., Gasteria pillansii L., Cymbopogon citratus, Brassica juncea, and Curcuma longa L. were determined by high-performance liquid chromatography with a diode-array detector method. The results revealed rich sources of important compounds such as robinin in the fruits and leaves of A. aethiopicus; caffeic acid in the tubers of A. aethiopicus and quercitrin in the leaves of G. pillansii. Further, relatively high antioxidant, antibacterial, and antifungal activities were observed in C. colocynthis fruit coat, S. alexandrina pods, and A. aethiopicus leaves, respectively. The relatively higher the bioactivities of plants extracts associated with the phenols in these plants, in particular, the more abundant the phenols. Therefore, it was concluded that the fruit coat of C. colocynthis, pods of S. alexandrina, and leaves of A. aethiopicus might be excellent sources of natural products. These plant extracts also have a wide spectrum of antimicrobial activities that could be used in the pharmaceutical industries and to control diseases

    Ispitivanje antidepresivnog, sedativnog i analgetskog djelovanja novih fuzioniranih derivata tiofena

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    This study was aimed at the synthesis of fused benzothiophene derivatives containing heterocyclic moiety. The reaction of the tetrahydrobenzo[b]thiophene derivatives 1a,b with ethoxycarbonylisothiocyanate afforded the thiourea derivatives 2a,b. Cyclization of the latter products gave the annulated benzo[b]thienopyrimidine derivatives 3a,b. Compounds 2a,b and 3a underwent a series of heterocyclization reactions through the reaction with some chemical reagents to give the new benzo[b]thienopyrimidine derivatives 5a,b to 8a-c. Also, this work was extended to study the potential role of the novel synthesized thiourea derivative 2a and benzo[b]thienopyrimidine derivatives 3a, 5b, 6a and 8b as antidepressant, sedative or analgesic agents at two doses (15 or 30 mg kg1 body mass). Some compounds (2a, 3a and 5b) showed mild antidepressant activity in the forced-swimming test. No compound showed sedative effect. Visceral pain evoked by i.p. injection of acetic acid in mice was significantly inhibited by all compounds at a high doses.U radu je opisana sinteza fuzioniranih derivata benzotiofena koji sadrže heterociklički ostatak bitan za farmakološko djelovanje. Tiourea derivati 2a,b dobiveni su reakcijom derivata tetrahidrobenzo[b]tiofena 1a,b s etoksikarbonilizotiocijanatom. Iz njih su dalje priređeni anulirani derivati benzo[b]tienopirimidina 3a,b. Spojevi 2a,b i 3a prevedeni su reakcijama heterociklizacije u benzo[b]tienopirimidine 5a,b-8a-c. Ispitivano je antidepresivno, sedativno i analgetsko djelovanje novosintetiziranih derivata tiouree 2a i benzo[b]tienopirimidina 3a, 5b, 6a i 8b u dvije doze (15 ili 30 mg kg1 tjelesne mase). Spojevi 2a, 3a i 5b pokazali su blago antidepresivno djelovanje u testu forsiranog plivanja, dok sedativni učinak nije pokazao niti jedan ispitivani spoj. Visceralna bol inducirana i.p. injekcijom octene kiseline u miševa značajno je inhibirana sa svim spojevima, ali u visokim dozama

    Parental awareness regarding pediatric antibiotic use in Madinah, Saudi Arabia

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    Purpose: To determine the level of awareness of antibiotic use in children in Madinah, Saudi Arabia, and to identify factors associated with parental decisions regarding it. Methods: Using a multiple-choice-question-based questionnaire survey, 1256 forms were distributed to visitors of major shopping malls in Madinah City to obtain socio-demographic and antibiotics knowledgebased data from October 2017 to January 2018. Differences in scores between and within groups on knowledge of parents about antibiotics were determined. Results: Most participants (67 %) had good basic knowledge of antibiotics: 69 and 40 % of respondents were aware of their side effects and antibacterial resistance, respectively. Participants in high age groups (> 46 years old) have a significantly higher mean knowledge score (55.4 ± 20.1, p < 0.05) than those in younger groups. Educational status increased the mean knowledge score by approximately 60 %, with the most educated group having a mean score of 61.2 ± 16.4 (p < 0.05). Conclusion: These results reveal the importance of awareness campaigns on antibiotic use and the role of healthcare professionals in the education of patients and parents on correct use of antibiotics, as well as the significance of antibacterial resistance. Keywords: Antibiotics misuse, Pediatrics, Patient education, Antibacterial resistanc

    Time course of collagen peak in bile duct-ligated rats

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    <p>Abstract</p> <p>Background</p> <p>One of the most useful experimental fibrogenesis models is the "bile duct-ligated rats". Our aim was to investigate the quantitative hepatic collagen content by two different methods during the different stages of hepatic fibrosis in bile duct-ligated rats on a weekly basis. We questioned whether the 1-wk or 4-wk bile duct-ligated model is suitable in animal fibrogenesis trials.</p> <p>Methods</p> <p>Of the 53 male Wistar rats, 8 (Group 0) were used as a healthy control group. Bile duct ligation (BDL) had been performed in the rest. Bile duct-ligated rates were sacrificed 7 days later in group 1 (10 rats), 14 days later in group 2 (9 rats), 21 days later in group 3(9 rats) and 28 days later in group 4 (9 rats). Eight rats underwent sham-operation (Sham). Hepatic collagen measurements as well as serum levels of liver enzymes and function tests were all analysed.</p> <p>Results</p> <p>The peak level of collagen was observed biochemically and histomorphometricly at the end of third week (P < 0.001 and P < 0.05). Suprisingly, collagen levels had decreased with the course of time such as at the end of fourth week (P < 0.01 and P < 0.05).</p> <p>Conclusion</p> <p>We have shown that fibrosis in bile duct-ligated rats is transient, i.e. reverses spontaneously after 3 weeks. This contrasts any situation in patients where hepatic fibrosis is progressive and irreversible as countless studies performed by many investigators in the same animal model.</p

    Evaluation of pyrene sorption–desorption on tropical soils

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    Sorption–desorption processes control soil-pollutant interactions. These processes determine the extent of pyrene transport in soils. Understanding sorption characteristics of pyrene is necessary in ascertaining its fate in soil. Laboratory batch experiments were conducted to study the sorptions–desorption of pyrene on eight soils from varying tropical agro-ecological zones (AEZs). The results showed that pyrene sorptions equilibria were attained within 720 min. Solution pH had a reciprocal effect on pyrene sorptions. Sorption was exothermic and increased with pyrene concentration in solution. The quantities of pyrene sorbed by each soil as well as the hysteresis were proportional to the percentage organic matter, and to some degree, the clay mineralogy. Sorption isotherms showed distributed reactivity involving several linear and non-linear isotherms. The present investigation showed that pyrene is likely to be more available to biota and reach the aquifer faster in low organic matter soils than those with relatively higher organic matter and more so in warmer climes

    Polymorphisms associated with the risk of lung cancer in a healthy Mexican Mestizo population: Application of the additive model for cancer

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    Lung cancer is the leading cause of cancer mortality in Mexico and worldwide. In the past decade, there has been an increase in the number of lung cancer cases in young people, which suggests an important role for genetic background in the etiology of this disease. In this study, we genetically characterized 16 polymorphisms in 12 low penetrance genes (AhR, CYP1A1, CYP2E1, EPHX1, GSTM1, GSTT1, GSTPI, XRCC1, ERCC2, MGMT, CCND1 and TP53) in 382 healthy Mexican Mestizos as the first step in elucidating the genetic structure of this population and identifying high risk individuals. All of the genotypes analyzed were in Hardy-Weinberg equilibrium, but different degrees of linkage were observed for polymorphisms in the CYP1A1 and EPHX1 genes. The genetic variability of this population was distributed in six clusters that were defined based on their genetic characteristics. The use of a polygenic model to assess the additive effect of low penetrance risk alleles identified combinations of risk genotypes that could be useful in predicting a predisposition to lung cancer. Estimation of the level of genetic susceptibility showed that the individual calculated risk value (iCRV) ranged from 1 to 16, with a higher iCRV indicating a greater genetic susceptibility to lung cancer
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