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Recycling System (recycling + system)
Selected AbstractsMARS®: a futile tool in centres without active liver transplant supportLIVER INTERNATIONAL, Issue 1 2007Chun-Tao Wai Abstract Background and aim: Studies on Molecular Adsorbent Recycling Systems (MARS®) showed inconclusive survival benefits. Patients and method: We evaluated the efficacy of MARS® for patients with either acute liver failure (ALF) or acute-on-chronic liver failure (AoCLF) at our centre, from February 2002 till April 2006 retrospectively. Results: Fifty ALF patients underwent median (range) three (1,10) sessions of MARS®. Acute exacerbations of chronic hepatitis B (n=26) and drug-induced liver injury (n=12) were the commonest causes. Living donors were available in 6, 2 paediatric patients underwent left lobe and four adults underwent right lobe living donor liver transplant. Among the 44 ALF patients without a suitable living donor, one underwent deceased donor liver transplant and survived, another 19-year-old male with acute exacerbations of chronic hepatitis B recovered without transplant, and the rest died. Twenty-six had AoCLF and underwent four (1,10) MARS® sessions. Sepsis (n=16) and upper gastrointestinal bleeding (n=4) were the commonest precipitating factors. None had a suitable living or deceased donor, suitable for transplantation during their hospitalization. Only one of 26 AoCLF patients survived the hospitalization, but the survivor died of sepsis 1 month later. Conclusion: In this non-randomized study, survival after MARS® was related to the availability of transplant, and in patients where living or deceased donor transplant was unavailable, MARS® was of little benefit. Randomized-controlled trials on MARS® are urgently needed to clarify its clinical utility. [source] Confocal imaging and tracking of the exocytotic routes for D -serine-mediated gliotransmissionGLIA, Issue 12 2008Magalie Martineau Abstract D -Serine is an astrocyte-derived regulator for N -methyl- D -aspartate receptors, but the intracellular routes of its trafficking are still largely unknown. Here, we combined confocal microscopy with colocalization quantification to track the astrocytic organelles that store D -serine. We report that D -serine colocalizes with the transfected eGFP-synaptobrevin/VAMP2 and eGFP-cellubrevin/VAMP3, two v-SNAREs of the regulated secretory pathway. No significant colocalization was found with markers of the endosomal sorting and recycling system: EEA1, eGFP-endobrevin/VAMP8, eGFP-TI-VAMP/VAMP7, LAMP1, and CD63. Blockade of vesicular budding with colchicine shows that secretory vesicles import D -serine downstream to the Golgi apparatus. Finally, treatment of astrocytes with the Ca2+ -ionophore A23187, glutamate agonists, or bradykinin trigger translocation of synaptobrevin/VAMP2 to the plasma membrane with a concomitant disappearance of D -serine from the regulated secretory pathway. Our results provide morphological evidence for a vesicular storage of D -serine in the regulated secretory pathway and the possible recruitment of these stores by Ca2+ mobilization to release D -serine. © 2008 Wiley-Liss, Inc. [source] Promotion of PDT Efficacy by a Bcl-2 AntagonistPHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 3 2008David Kessel Photodynamic therapy (PDT) directed against the endoplasmic reticulum (ER) is also known to target antiapoptotic Bcl-2 family proteins. This effect is associated with the initiation of both apoptosis, a cell death pathway, and autophagy, an organelle recycling system that can lead to survival or cell death. In this study, we examined the ability of the Bcl-2 antagonist HA14-1 to promote the photodynamic efficacy of PDT directed at the ER. At concentrations that independently caused only a small loss of viability, HA14-1 markedly enhanced the proapoptotic and phototoxic effects of ER photodamage. These results provide additional evidence that the antiapoptotic properties of Bcl-2 constitute an important determinant of photokilling, and demonstrate that synergistic effects can result when PDT is coupled with pharmacologic suppression of Bcl-2 function. [source] Thermal degradation of a brominated bisphenol a derivativePOLYMERS FOR ADVANCED TECHNOLOGIES, Issue 11-12 2003M. P. Luda Abstract The thermal degradation of 2,6,2,,6,,tetrabromo-4,4,-isopropylidene-di phenol (tetrabromobisphenol A) (TBBPA) has been investigated and a mechanism for its thermal degradation is suggested. TBBPA is a comonomer widely used in epoxy and in unsaturated polyester resins to impart fire retardance. These resins find a common use in electric and electronic equipment. The presence of bromine atoms is the key factor in fire retardant activity, while on the other hand it represents an ecological problem when pyrolytic recycling is programmed at the end of the useful life of such items. However, pyrolysis is the more advantageous recycling system for thermosetting resins and thus efforts should be made to control the pyrolysis in order to avoid or minimize the development of toxics. Homolytic scission of the aromatic bromine and condensation of aromatic bromine with phenolic hydroxyl are the main processes occurring in the range 270,340°C. A large amount of charred residue is left as a consequence of condensation reactions. HBr and brominated phenols and bisphenols are the main volatile products formed. Brominated dibenzodioxins structures are included in the charred residue and not evolved in the volatile phases. Copyright © 2003 John Wiley & Sons, Ltd. [source] Optimum water temperature boosts the growth performance of Nile tilapia (Oreochromis niloticus) fry reared in a recycling systemAQUACULTURE RESEARCH, Issue 6 2008Abdel-Fattah M El-Sayed No abstract is available for this article. [source] Effects of photoperiod on growth and spawning efficiency of Nile tilapia (Oreochromis niloticus L.) broodstock in a recycling systemAQUACULTURE RESEARCH, Issue 12 2007Abdel-Fattah M El-Sayed Abstract This study was conducted to evaluate the effects of photoperiod on the growth, feed conversion ratio (FCR) and spawning performance of Nile tilapia (Oreochromis niloticus) broodstock. Duplicate groups of two males (66±3.04 g) and six females (50.5±1.58 g) were stocked in 0.4 m3 fibreglass tanks in a recirculating water system at a male:female ratio of 1:3. The fish were subjected to four photoperiod treatments: 24:0 light:dark (L:D), 18L:6D, 12L:12D and 6L:18D. Light intensity was kept constant at about 2500 lx throughout the study. The fish were fed a commercial tilapia diet (35% crude protein and 16.6 MJ GE kg,1) at a daily rate of 2,3% of tank biomass, twice a day, for 130 days. Males grew significantly faster than females under all photoperiod regimes. The best growth rate and FCR were attained at 18L:6D, followed by 24L:0D, 12L:12D and 6L:18D respectively. The number of eggs per female, number of eggs per spawn and number of spawnings per female were all significantly higher in the 12L:12D treatment than in all other photoperiod cycles. Interspawning intervals and days elapsed per spawn were also shorter in the 12L:12D treatment. The time to first spawning was slightly longer in the 24L:0D and 6L:18D than in 12L:12D and 18L:6D light phases. The 18L:6D and 6L:18D photoperiods produced the lowest spawning performance. It is concluded that a 12L:12D photoperiod regime should be adopted for maximum fecundity, seed production and spawning frequencies of Nile tilapia broodstock reared in intensive, recirculating systems. If maximum reproduction is desired, a near-natural day length photoperiod should be used. [source] Facilitating substance phase-out through material information systems and improving environmental impacts in the recycling stage of a productNATURAL RESOURCES FORUM, Issue 3 2010Daniel PaskaArticle first published online: 4 AUG 2010 Abstract The amount of electrical and electronic products is increasing rapidly, and this inevitably leads to the generation of large quantities of waste from these goods. Some of the generated e-waste ends up in regions with sub-standard recycling systems and may be processed under poor conditions. During uncontrolled incineration, halogenated dioxins and furans can be generated from brominated and chlorinated compounds in the products. In order to reduce the health and environmental risks involved in the recycling stage of the life cycle of electronics, an effective design-for-environment process must be established during the product development phase. Knowledge of the chemical substances in the product is crucial to being able to make informed decisions. Through full knowledge of the material content of procured components, phase-outs of unwanted substances, such as halogenated substances, can be performed in an effective manner. Therefore, information is the key to success in phasing-out substances; facilitating compliance of legal provisions for manufacturers of electrical and electronic devices; and improving the environmental footprint of products as they reach the end of the life cycle. After an introduction to the challenges of electronics waste management, this paper describes supply chain information systems and how they are used to facilitate substance phase-outs in the electronics industry. Sony Ericsson has been working with phase-outs of unwanted substances since it was founded in 2001. Through the introduction of a material declaration system that keeps track of all substances in the components used in the company's products, Sony Ericsson has been able to replace unwanted substances to improve environmental impacts at the recycling stage of a product. [source] | |||||||||||||