110 research outputs found

    Assessment of heavy metals in Lake Uluabat, Turkey

    Get PDF
    The accumulation of heavy metals (Cu, Ni, Zn, Cd, Pb, Cr, B, As) was measured in water, plankton and sediment samples taken from different areas of Lake Uluabat during January 2003 to February 2004.The sequential extraction used in this study is useful to assess the potential mobility of heavy metals in the sediment indirectly. In this study, Cu, Pb, Cr, Cd, Ni and Zn concentrations were detected at higherlevels at Lake Uluabat for selected stations, especially in plankton samples. The magnitude of heavy metal concentrations in water and plankton samples was determined as B>Zn>As>Cd>Pb>Ni>Cr andZn>Ni>Cu>Cr>Cd>Pb, respectively. The mobile heavy metals in sediment samples were sequences as Pb>Cu>Cr>Ni>Cd>Zn, whereas the magnitude of easily mobilizable metal concentration was determinedas Pb>Ni>Cr>Cu>Cd>Zn. Concentration of Cu and Cr in mobile fraction is detected higher than in easily mobilizable fraction. Concentration of Pb, Cd, Zn and Ni in mobile fraction is detected in lower levels than in easily mobilizable fraction

    Energy Landscape and Global Optimization for a Frustrated Model Protein

    Get PDF
    The three-color (BLN) 69-residue model protein was designed to exhibit frustrated folding. We investigate the energy landscape of this protein using disconnectivity graphs and compare it to a Go model, which is designed to reduce the frustration by removing all non-native attractive interactions. Finding the global minimum on a frustrated energy landscape is a good test of global optimization techniques, and we present calculations evaluating the performance of basin-hopping and genetic algorithms for this system.Comparisons are made with the widely studied 46-residue BLN protein.We show that the energy landscape of the 69-residue BLN protein contains several deep funnels, each of which corresponds to a different β-barrel structure

    Comparative Analysis of the Volatile Fraction of Fruit Juice from Different Citrus Species

    Get PDF
    The volatile composition of fruit from four Citrus varieties (Powell Navel orange, Clemenules mandarine, and Fortune mandarine and Chandler pummelo) covering four different species has been studied. Over one hundred compounds were profiled after HS-SPME-GC-MS analysis, including 27 esters, 23 aldehydes, 21 alcohols, 13 monoterpene hydrocarbons, 10 ketones, 5 sesquiterpene hydrocarbons, 4 monoterpene cyclic ethers, 4 furans, and 2 aromatic hydrocarbons, which were all confirmed with standards. The differences in the volatile profile among juices of these varieties were essentially quantitative and only a few compounds were found exclusively in a single variety, mainly in Chandler. The volatile profile however was able to differentiate all four varieties and revealed complex interactions between them including the participation in the same biosynthetic pathway. Some compounds (6 esters, 2 ketones, 1 furan and 2 aromatic hydrocarbons) had never been reported earlier in Citrus juices. This volatile profiling platform for Citrus juice by HS-SPME-GC-MS and the interrelationship detected among the volatiles can be used as a roadmap for future breeding or biotechnological applications

    Thymoquinone: An edible redox-active quinone for the pharmacotherapy of neurodegenerative conditions and glial brain tumors. A short review

    No full text
    There exist few efficient agents in the neurological and neurosurgical armamentarium for treatment of neurotrauma, refractory seizures and high grade glial tumors. Pathophysiological conditions of diverse neural injuries have converging common pathways including oxidative stress and apoptosis. Targeted therapies have been throughly investigated, but limited success has been achieved until now. Phytochemical drugs may provide easily achievable and cheap adjunctive sources. Thymoquinone is an edible quinone obtained from Nigella sativa seed oil and exerts powerful antiinflammatory, antioxidant and antitumor activities in experimental models. Recently emerging studies conducted with animal models suggest that thymoquinone - bearing a very simple molecular structure - significantly crosses the blood brain barrier and exerts neuromodulatory activities. Indeed, in animal studies, the following actions of thymoquinone were demonstrated: 1-Protection against ischemic brain damage. 2-Reduction of epileptic seizures and associated cerebral oxidative injury. 3-Reduction of morphine tolerance and associated oxidative brain damage. 4-Anxiolytic effects and reduction of immobility stress-associated cerebral oxidative injury. 5-Reduction of diabetes-induced cerebral oxidative stress, 6-Reduction of cerebral oxidative injuries induced by noxious exposures including toluene, lead and ionizing radiation. Substantial in vitro data suggest that thymoquinone may be beneficial in treatment of glial tumors. However, there is no clinical study investigating its antitumor effects. In fact, thymoquinone suppresses growth and invasion, and induces apoptosis of glial tumor cells via degrading tubulins and inhibiting 20S proteasome, telomerase, autophagy, FAK and metalloproteinases. A simple and easily available agent may be a promising adjunctive treatment option in neurological and neurosurgical practice. (C) 2016 Elsevier Masson SAS. All rights reserved

    Time to resolution of isolated antenatal hydronephrosis with anteroposterior diameter 20 mm

    No full text
    Data regarding spontaneous resolution of mild hydronephrosis consist of different etiologies, and hence, it is heterogeneous. The aim of this study is to evaluate spontaneous resolution rates and the time to complete resolution of antenatally detected isolated hydronephrosis in patients with renal pelvis antero-posterior diameter (RPAPD) 20mm. Retrospective chart review of patients who were admitted to our pediatric nephrology clinic for the evaluation of antenatal hydronephrosis between 2011 and 2017 was conducted. Patients that had hydronephrosis with RPAPD 20mm, <SFU (Society for Fetal Urology) grade IV on initial postnatal evaluation, and 3months of follow-up with at least two renal ultrasounds (US) were included. Complete resolution of hydronephrosis was regarded as SFU grade 0 with a RPAPD of <7mm. Patients with ureteric and lower urinary tract abnormalities were excluded. There were a total of 276 patients who met the inclusion criteria. Median follow-up was 16months (range 3-96months). Hydronephrosis completely resolved in 198 patients (71.7%). Surgery was not required in any of the patients; however, nine patients (3.3%) showed progression to higher grades of hydronephrosis or increase in AP diameter. Median time to complete resolution of hydronephrosis was 6months (range 2-35months) in our study. Those with AP diameter <10mm became normal in median of 5months, while it took median 11months for patients with AP diameter 10-20mm to become normalized (p<0.001).Conclusion: Isolated antenatal hydronephrosis with RPAPD 20mm would spontaneously resolve in 71.7% of the cases. Resolution may be expected to happen in 3years, while the majority will take place in the first year of life
    corecore