Flavopiridol Induces Apoptosis via Mitochondrial Pathway in B16F10 Murine Melanoma Cells and a Subcutaneous Melanoma Tumor Model

Flavopiridol is a cyclin-dependent kinase (CDK) inhibitor that promotes cell cycle arrest. We aimed to examine the anti-proliferative effects of the flavopiridol and oxaliplatin combination on p16INK4A deficient melanoma cells B16F10 and also its apoptotic effects on a subcutaneously injected B16F10 allograft melanoma tumor model. Flavopiridol and oxaliplatin treated B16F10 cell viability was determined by MTT assay. C57BL6 mice were injected with B16F10 cells and treated with flavopiridol after tumor implantation. BRAF and BCL2L1 mRNA expression levels were measured using reverse transcription-polymerase chain reaction (RT-PCR). Caspase 9 and caspase 3/7 activity were determined by activity assay kits. Proliferating cell nuclear antigen (PCNA) and B-cell lymphoma 2 (BCL-2) protein expression levels were analyzed immunohistochemically. Flavopiridol and oxaliplatin decreased cell death. Flavopiridol enhanced caspase 3/7 and caspase 9 activities in vitro and in vivo in a dose dependent manner via the mitochondrial apoptotic pathway. Even though there was a significant increase in Bcl-2 staining, PCNA staining was decreased in flavopiridol-administered mice. Decreased PCNA expression showed antiproliferative effects of flavopiridol which might be the result of cell-cycle arrest. Flavopiridol can be used as a cell cycle inhibitor, which induced apoptosis through the mitochondrial pathway, independently from BCL2 in B16F10 cells and B16F10 injected C57BL6 allografts. </p

Chilling Tolerance Of Cicer Arietinum Lines Evaluated By Photosystem Ii And Antioxidant Activities

Two chickpea (Cicer arietinum L.) lines (AKN 87 and AKN 290) that have different chilling susceptibilities were exposed to 2 chilling temperatures (4 and 2 degrees C), either cold-acclimated (10 degrees C) or nonacclimated (25 degrees C), in order to understand and compare physiological and biochemical changes at the vegetative stage. Chilling temperatures resulted in reduced growth parameters, particularly in cold-acclimated lines, whereas nonacclimated plants exhibited the lowest water contents. Cold acclimation treatment led to protective changes of increased flavonoid, proline, and antioxidant enzyme activities, mostly superoxide dismutase (SOD) and ascorbate peroxidase (APX), in the lines. However, the 10 degrees C treatment did not significantly influence photosystem II (PSII) activity in chickpea plants. In chilling treatments, cold-acclimated plants exhibited better tolerance; of the 2 lines, AKN 87 had the higher PSII photochemical activity. The chlorophyll contents of lines decreased, while the anthocyanin and flavonoid contents of lines increased at decreasing temperatures. MDA and proline accumulation increased with the severity of the chilling stress. In conclusion, when the plants were exposed to cold acclimation, chilling induced the enhancement of antioxidant enzyme activities, particularly SOD and APX. The results demonstrated that cold acclimation reduced the deteriorative effects of chilling and provided better tolerance, specifically in AKN 87. The line AKN 87 has greater potential for cultivation as a chilling-tolerant cultivar.WoSScopu

Effects of Residual Xanthate on Flotation Efficiency of a Cu-Zn Sulfide Ore

Reuse of process water in the flotation of sulfide ores has crucial importance for environmental sustainability and improved process economy. However, the chemistry of process water may be a critical subject for the flotation efficiency as the dissolved ion concentration increases with water reuse. In this study, the effects of water reuse on the flotation efficiency of a Cu-Zn sulfide ore were investigated. The flotation flowsheet consists of a pre-flotation section to remove the naturally floatable talc particles, and sequential copper and zinc flotation sections. Calcium, sulfate, thiosulfate, and xanthate were found as major contaminating ionic species in the process water discharged from flotation circuits. The flotation tests with recirculated water from the zinc rougher tailing revealed that the presence of residual xanthate caused unintentional activation of copper minerals in the pre-float section. Copper recovery increased in the pre-flotation section and resulted in the loss of copper to the pre-float concentrate, which is considered as a tailing stream in the current flowsheet. Various types of activated carbon samples were tested to remove the residual xanthate from the tailing water. The carbon samples could be regenerated by heat treatment and reused for water treatment. Performance of the activated carbon samples was directly related to the pore size and surface area. Carbon-treated tailing water could be re-used in flotation without affecting the flotation performance

Effects of Residual Xanthate on Flotation Efficiency of a Cu-Zn Sulfide Ore

Reuse of process water in the flotation of sulfide ores has crucial importance for environmental sustainability and improved process economy. However, the chemistry of process water may be a critical subject for the flotation efficiency as the dissolved ion concentration increases with water reuse. In this study, the effects of water reuse on the flotation efficiency of a Cu-Zn sulfide ore were investigated. The flotation flowsheet consists of a pre-flotation section to remove the naturally floatable talc particles, and sequential copper and zinc flotation sections. Calcium, sulfate, thiosulfate, and xanthate were found as major contaminating ionic species in the process water discharged from flotation circuits. The flotation tests with recirculated water from the zinc rougher tailing revealed that the presence of residual xanthate caused unintentional activation of copper minerals in the pre-float section. Copper recovery increased in the pre-flotation section and resulted in the loss of copper to the pre-float concentrate, which is considered as a tailing stream in the current flowsheet. Various types of activated carbon samples were tested to remove the residual xanthate from the tailing water. The carbon samples could be regenerated by heat treatment and reused for water treatment. Performance of the activated carbon samples was directly related to the pore size and surface area. Carbon-treated tailing water could be re-used in flotation without affecting the flotation performance

Effects of Calcium Dobesilate on Adrenomedullin, Nitric Oxide and Superoxide Dismutase Levels in Experimental Stress Ulcer Formation

Objective: In the present study, we investigated the adrenomedullin (AM) and total nitric oxide (NOx) [nitrite plus nitrate] levels in experimentally induced stress ulcer model in rats. To examine the relation with oxidative stress, we measured the levels of thiobarbituric acid-reactive substances (TBARS) as an index of lipid peroxidation, and superoxide dismutase (SOD) activity together with the effect of calcium dobesilate (Ca-D) as well. Material and Methods: In this study, 33 female Wistar-Albino rats weighing about 230 g (200-250) aged 7-8 months were used. The rats were divided into 3 groups each containing 11 rats. The Ca-D-treated stress group received daily single oral dose of calcium dobesilate for 10 days (group 1). The saline-treated stress group received daily single oral dose of saline (same volume with calcium dobesilate) for 10 days (group 2). The non-stressed control group received daily single oral dose of saline (same volume with calcium dobesilate) for 10 days (group 3). In all groups of rats, plasma AM, NOx and TBARS levels as well as gastric mucosa NOx, TBARS levels. and SOD activity were determined. Results: In group 2 plasma AM (p< 0.001), plasma NOx (p< 0.001), gastric mucosa NOx (p< 0,001), and gastric mucosa TBARS levels (p< 0.01) were significantly higher than the levels in the control group. In group 1, elevated plasma NOx, gastric mucosa NOx, and plasma TBARS levels were found compared to the control group. On the other hand, the average plasma adrenomedullin and gastric mucosa TBARS levels in group 2 were significantly higher (p< 0.001) and plasma NOx levels were lower (p< 0.01) compared to group 1. In addition, in group 1 and 2, decreased SOD activity (p< 0.001) was found in gastric mucosa compared to the control group. Conclusion Elevated levels of AM and NOx may be generated to protect the organism as a response to increased oxidative stress. Calcium dobesilate may partially protect the organism against oxidative stress in stress ulcer pathogenesis, probably in relation to NO. However, further studies will be required to evaluate the role of calcium dobesilate in stress ulcer pathogenesis because of low levels of plasma AM and high levels of plasma TBARS in Ca-D-treated stress group

Thermodynamic investigation of organic Rankine cycle energy recovery system and recent studies

Recently, new environment-friendly energy conversion technologies are required for using energy resources valid to power generation. Accordingly, low-grade heat sources as solar heat, geothermal energy, and waste heat, which have available temperatures ranging between 60 and 200°C, are supposed as applicants for recent new generation energy resources. As an alternative energy source, such low-grade heat sources usage generating electricity with the help of power turbine cycles was examined through this study. Such systems have existing technologies applicable at low temperatures and a compact structure at low cost, however, these systems have a low thermal efficiency of the Rankine cycles operated at low temperatures. An organic Rankine cycle is alike to a conventional steam power plant, except the working fluid, which is an organic, high molecular mass fluid with a liquid-vapor phase change, or boiling point, at a lower temperature than the water-steam phase change. The efficiency of an organic Rankine cycle is about between 10% and 20%, depending on temperature levels and availability of a valid fluid

The Impact of Pulp Temperature on the Flotation Performance of Copper-Lead-Zinc Sulphide Ore

Flotation performance can significantly be affected by seasonal variations due to the changes in water temperature and pulp temperature, type and concentration of dissolved ions in process water. Extreme temperature conditions could be the major factor affecting flotation performance and mask the influence of water chemistry. Therefore, the interactive effects of the temperature and water chemistry should be taken into consideration, particularly for mine sites experiencing extreme temperature conditions. In this paper, effects of temperature, sulphate (SO42−), thiosulphate (S2O32−) and calcium (Ca2+) ions on the flotation performance of a Cu-Pb-Zn complex sulfide ore were investigated using a statistical experimental design and modelling approach. The results were evaluated using ANOVA and regression analysis to determine the significant parameters and derive individual regression models for each flotation response using Design Expert software version 6.0.8. Individual regression models were developed for mass pull, water recovery, grade and recovery of the sulfide minerals using the statistically significant main effects and their interactions. The models were used to determine the concentration of the dissolved ions and pulp temperature required to achieve the maximum zinc recovery, maximum zinc grade or the optimum zinc grade and recovery. The results showed that the water chemistry (i.e., the concentrations of Ca2+, SO42− and S2O32−) affected the flotation performance significantly at low temperature (25 °C). At high pulp temperature (60 °C), however, the temperature was the dominant parameter and masked the effects of water chemistry. Details of the statistical experimental design, discussions of the effects of experimental factors and their interactions on flotation performance, and the development of regression models are presented in this paper

Electrospinning, preparation and photoluminescence properties of CoNb2O6:Dy3+ incorporated polyamide 6 composite fibers

WOS: 0004087535000313 mol% Dy3+ doped cobalt niobate (CoNb2O6) compound has been synthesized by molten salt method using Li2SO4/Na2SO4 salt mixture as a flux at a relatively low temperature as compared to solid state reaction. X-ray diffraction patterns of 3 mol% Dy3+ doped CoNb2O6 compound indicated orthorhombic columbite single phase. SEM analysis revealed that Dy3+ doped CoNb2O6 has a submicron particle size. The photoluminescence of CoNb2O6: Dy3+ phosphor has exhibited in a dominant yellow emission at 579 nm with an excitation wavelength of 366 nm. The synthesized submicron phosphor particles were successfully incorporated into Polyamide 6 fibers by utilizing electrospinning technique. The average fiber diameter obtained through the process ranged between 192 +/- 62 nm and 387 +/- 341 nm. Mechanical characteristics of the produced nanofibrous webs were strongly influenced by the fiber morphologies and size (diameter) distribution rather than the phosphor particles incorporated into the fibers and/or located on the web. The photoluminescence of composite fiber material increased with the increasing phosphor content. (C) 2016 Elsevier B.V. All rights reserved