95 research outputs found

    Structure, density and shrinkage variation within silver maple

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    Antioksidativno djelovanje metanolnih ekstrakata listova sedam egipatskih vrsta roda Cassia

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    In the present study, antioxidant activity of methanolic extracts of the leaves of seven Egyptian Cassia species was investigated using two methods, the phosphomolybdate method and 1,1 diphenyl-2-picrylhydrazyl radical (DPPH•) scavenging activity method. The results revealed that C. glauca is the most potent species and that the activity of other plant species decreases in the following order C. grandis > C. nodosa > C. fistula > C. didymobtrya > C. occidentalis > C. sophera. Defatted methanolic extract of the most active plant C. glauca was subjected to fractionation process using different organic solvents such as CHCl3, EtOAc and BuOH. Antioxidant activities of these fractions were investigated and the results showed that ethyl acetate fraction possessed high activity. Total phenolic and flavonoid concentration of each plant extract were determined using the Folin-Ciocaltu reagent and aluminum chloride. Correlation between radical scavenging capacities of extracts and total phenolic concentration was observed.U radu je ispitano antioksidativno djelovanje metanolnih ekstrakata listova sedam egipatskih vrsta roda Cassia koristeći fosfomolibdatnu metodu i metodu vezanja slobodnih 1,1-difenil-2-pikrilhidrazil radikala (DPPH.). Rezultati pokazuju da C. glauca ima najveću aktivnost te da se djelovanje smanjuje sljedećim redom: C. grandis C. nodosa C. fistula C. didymobtrya C. occidentalis C. sophera. Odmašćeni metanolni ekstrakt najaktivnije biljke C. glauca frakcioniran je pomoću različitih organskih otapala kao što su CHCl3, EtOAc i BuOH. Ispitivanje antioksidativnog djelovanja pojedinih frakcija pokazuje da je etil-acetatna frakcija najaktivnija. Pomoću Folin-Ciocaltuovog reagensa i aluminijevog klorida određena je ukupna koncentracija fenola i flavonoida svakog pojedinog ekstrakta. Uočena je korelacija između sposobnosti hvatanja slobodnih radikala i ukupnog sadržaja fenola

    Multislice CT in sinonasal polypi; Functional endoscopic sinus surgery correlation

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    Background: Nasal and sinus illnesses are diagnosed with computed tomography (CT) because CT scans effectively bone anatomy is depicted with air spaces, opacified sinuses, and detailed structural details. Objective: The significance of using multislice CT for the detection and characterization of sinus polyps and the relationship between the CT findings and those of functional endoscopic sinus surgery (FESS) have been studied. Patients and Methods: At Zagazig University's Radiodiagnosis Department, we conducted this study on 18 patients, 10 of which were females and eight were males, from a total of 33 individuals. To emphasize the role of multislice (CT) in diagnosis and characterization of sinonasal polypi during functional endoscopic sinus surgery, numerous CT parameters were used and correlated with operational findings. Results: There was a strong correlation calculated by Spearman correlation coefficient (r) for right-sided and left-sided surgeries of 0.76 and 0.87, respectively, for operative endoscopic and Lund-Mackay staging scores. Conclusion: Based on functional endoscopic sinus results, CT and diagnostic endoscopy may be the new standard of care in the diagnosis of sinonasal diseases

    Propiedades y durabilidad de los cementos adicionados con metacaolín

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    This paper evaluates the optimal calcination temperature and replacement ratio to ensure high metakaolin (MK) pozzolanicity in blended cement. The MK used was prepared by firing two types of local at temperatures ranging from 700 to 850 ºC. Dry blends of ordinary Portland cement (OPC) and varying proportions of MK were mixed with the amount of water required to ensure optimal consistency of the resulting pastes. The specimens were cured at 100% RH for 24 h and then immersed in water for 3, 7, 28, 90 or 180 days. At each test time, the degree of hydration and compressive strength of the hardened cement pastes were measured The findings showed that the most suitable calcination temperature to obtain metakaolin is 700 ºC, while the optimal replacement ratio ranges from 25 to 30%. DTA was used to determine the phases comprising the hydration products forming at the ages studied. Pure OPC and OPC-MK specimens were immersed in 3% NaCl and 5% MgSO4 solutions for 30, 90 and 180 days to measure their durability. The OPC-MK pastes immersed in the 3% NaCl solution were observed to be highly resistant to chloride attack.El presente trabajo evalúa el comportamiento puzolánico de metacaolín (MK), producto de la calcinación a distintas temperaturas de dos tipos de caolín local de composiciones químicas diferentes, al incorporarse al cemento en diferentes proporciones. Se preparó un cemento adicionado mediante la mezcla en seco de cemento Portland ordinario (OPC) y metacaolín (MK), a los que se añadió la cantidad óptima de agua para obtener una pasta de la consistencia deseada. Las probetas se curaron a una HR del 100% durante 24 horas, sumergiéndose posteriormente en agua durante 3, 7, 28, 90 o 180 días. A cada tiempo de ensayo se controló el grado de hidratación de las pastas endurecidas y se comprobó la resistencia a la compresión de las probetas cúbicas a las edades de curado establecidas. Los resultados obtenidos indican que la temperatura más adecuada para la calcinación del caolín es de 700 °C y que el porcentaje óptimo de éste en la mezcla se encuentra entre el 25 y el 30%. Las fases que componen los productos resultantes de la hidratación se identificaron mediante ATD a distintas edades de curado. Se estableció la durabilidad del OPC puro y de las mezclas de OPC-MK en disoluciones de NaCl al 3% y MgSO4 al 5% tras 30, 90 y 180 días de inmersión. Se concluyó que las pastas de OPC-MK muestran una elevada resistencia al ataque del ion cloruro

    Propiedades y durabilidad del cemento con adición de metacaolín: mortero y hormigón

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    This article explores the effect of metakaolin, a pozzolan, on concrete performance. Compressive and splitting tensile strength were found for specimens cured for up to 360 and 90 days, respectively. Changes were recorded in the compressive strength of specimens exposed to salt (chloride and sulfatechloride solutions), and chloride penetration and binding capacity were measured. The findings were compared to the results for concrete prepared with ordinary Portland (OPC) and moderate heat of hydration (Type II) cement. MK was found to have a very positive effect on 28-day concrete strength, due to microstructure improvement of the hydrated cement. Replacing cement with metakaolin effectively raised concrete resistance to chloride attack. Concrete containing metakaolin proved to be substantially more durable in sulfate-chloride environment.En este trabajo se estudia el efecto del metacaolín sobre las prestaciones del hormigón. Las probetas curadas a 360 y 90 días se sometieron a ensayos de resistencia a compresión y de tracción indirecta respectivamente. Se hizo un seguimiento de la resistencia a la compresión de los materiales ante el ataque de sales (soluciones de cloruro y de sulfato-cloruro) y, se midió la penetración de cloruros y la capacidad de los hormigones de inmovilizar estos iones. Los resultados se compararon con los obtenidos con hormigones elaborados con cemento pórtland ordinario (OPC) y, con cemento de calor de hidratación moderado (tipo II). El MK resultó influir muy positivamente en la resistencia del hormigón a 28 días debido a la mejora de la microestructura del cemento hidratado. La sustitución de cemento por metacaolín aumentó la resistencia del hormigón al ataque de cloruros. El hormigón con metacaolín demostró ser más duradero en entornos de sulfato-cloruro que los hormigones elaborados con OPC o con cemento de tipo II. Los perfiles de concentración de cloruros a distintas profundidades y la diferencia entre los contenidos de cloruro libre y total, mostraron claramente que el cemento con metacaolín reducía la penetración de cloruros en el hormigón y, aumentaba su capacidad para combinar con iones cloruro. La conclusión general fue que podía fabricarse material puzolánico utilizable, mediante la activación térmica del caolín local

    Bioactive compounds from Acokanthera oblongifolia

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    One cardiotonic glycoside, three triterpenes and one steroidal glycoside were isolated from Acokanthera oblongifolia fruits (pericarp) growing in Libya. Their structures were investigated by extensive application of IR, MS, 1DNMR and 2DNMR spectroscopy. The isolated compounds have evidenced in-vitro cytotoxicity on selected human cell lines (A-549, H-1299) when compared to doxorubicin. Keywords: Cardenolide; Acokanthera oblongifolia; antitumor activity; lung carcinoma cell line (A-549, H-1299)

    Bioactive chemical constituents of Curcuma longa L. rhizomes extract inhibit the growth of human hepatoma cell line (HepG2)

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    The present study was designed to identify the chemical constituents of the methanolic extract of Curcuma longa L. rhizomes and their inhibitory effect on a hepatoma cell line. The methanolic extract was subjected to GC-MS analysis to identify the volatile constituents and the other part of the same extract was subjected to liquid column chromatographic separation to isolate curcumin. The inhibition of cell growth in the hepatoma cell line and the cytopathological changes were studied. GC-MS analysis showed the presence of fifty compounds in the methanolic extract of C. longa. The major compounds were ar-turmerone (20.50 %), β-sesquiphellandrene (5.20 %) and curcumenol (5.11 %). Curcumin was identified using IR, 1H and 13C NMR. The inhibition of cell growth by curcumin (IC50 = 41.69 ± 2.87 µg mL–1) was much more effective than that of methanolic extract (IC50 = 196.12 ± 5.25 µg mL–1). Degenerative and apoptotic changes were more evident in curcumin-treated hepatoma cells than in those treated with the methanol extract. Antitumor potential of the methanolic extract may be attributed to the presence of sesquiterpenes and phenolic constituents including curcumin (0.051 %, 511.39 µg g–1 dried methanol extract) in C. longa rhizomes

    Antidepressant-Like Effect of Selected Egyptian Cultivars of Flaxseed Oil on a Rodent Model of Postpartum Depression

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    Flaxseed (Linum usitatissimum L.) is a multipurpose crop with health promoting potential. This study was undertaken to investigate the fatty acid profile and yield of fixed oil of six Egyptian flaxseed cultivars. The selected cultivars with the highest content of polyunsaturated fatty acids (PUFAs) (G9 and G10) were assessed for their antidepressant-like effect in rat model of postpartum depression (PPD) induced by hormone-simulated pregnancy followed by hormone withdrawal and compared to fluoxetine. As compared to control group, administration of G9 and G10 (270 mg/kg/day, p.o) for two weeks during the postpartum period can alleviate anxiety and depressive-like behaviors and biochemical changes in PPD-induced rats. This was confirmed by evaluation of anxiety-like behaviors (elevated plus maze, open field test, and forced swim test tests), in addition to biochemical analysis (brain monoamine oxidase-A, corticosterone level, proinflammatory cytokines, and hippocampal redox state). In conclusion, flaxseed oil of Egyptian cultivars G9 and G10 exhibited significant antidepressant-like effect in rat model of PPD without affecting locomotor activity. At the treatment doses, the antidepressant-like activity of Giza 9 oil is comparable to fluoxetine
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