Chelating agent

Soil application of synthetic Fe(III)-chelates, mainly those derived from ethylendiamine di(o-hydroxyphenylacetic) acid (ED-DHA) and ethylendiamine di(2-hydroxy-4-methylphenylacetic) acid (EDDHMA), is the most effective, but the most expensive practice used to correct iron deficiency in plants growing on calcareous soils. Previous studies that compared the effectiveness of EDDHA/Fe 3+ and EDDHMA/Fe 3+ always used commercial products and their results are contradictory. In this study, the effectiveness of commercial EDDHA/Fe 3+ and EDDHMA/Fe 3+ fertilizers to correct iron chlorosis in three different crops (sunflower, peach and pear) was compared using doses calculated with the actual content of chelated iron determined by HPLC. The effectiveness of the Fe(III)-chelate derived from the ethylenediamine di(2-hydroxy-5sulfophenylacetic) acid (EDDHSA), that recently has been marketed as iron fertilizer, was also tested in the sunflower and pear experiments. For the three experiments, sev...

Lanthanum carbonate is a new nonaluminium, noncalcium phosphate binder. The drug is well-tolerated its side-effects seem comparable to those of other phosphate binders. The most frequent side-effects are gastrointestinal complications. Cerny [New England Journal ...

Produced water management has become one of the key factors to sustainable development of natural gas/oil resources. The substantial quantities of saline water present intractable environmental threats and also increase oil/gas production costs through produced water disposal such as deep well reinjection. Developing high-efficient and flexible treatment systems that can be operated at low costs is of high interests for producers and state regulators. Beneficial use of produced water could represent a new water resource especially for areas with inadequate existing supplies. Furthermore, some produced waters generated are also characterized by elevated concentrations of recoverable constituents, for example iodide. Recovering iodide from brine could offer additional benefits besides providing methane gas, reusing produced water, or reducing brine disposal volume.The advent of ultra-low pressure reverse osmosis (ULPRO) membranes and nanofiltration (NF) membranes with high desalting degree might offer a viable option for produced water treatment because these membranes can be as effective as reverse osmosis (RO) in removing certain solutes from water while requiring considerably less feed pressure resulting in lower operating costs. The objectives of this research were to investigate the viability of ULPRO and NF membranes as potential techniques to treat produced water by meeting water quality standards and concentrating iodide in the brine. The produced water extracted from sandstone aquifer in Eastern Montana was characterized as brackish groundwater of sodium chloride type with total dissolved solids (TDS) concentration of 5300 mg/L, absence of hydrocarbons, and average iodide concentrations of 55 mg/L. The produced water exhibited a very high potential to membrane fouling indicated by silt density index (SDI) measurements due to the presence of small particles and inorganic constituents.The studied candidate membranes included one RO membrane (TFC-HR, Koch Membrane Systems), three ULPRO membranes XLE (Dow/Filmtec), TFC-ULP (Koch) and TMG-10 (Toray America), and three NF membranes NF-90 (Dow/Filmtec), TFC-S (Koch), and ESNA (Hydranautics). Bench-scale cross-flow flat sheet test units were employed to assess the candidate membranes using the produced water with focus on fouling potential, iodide recovery, and general salt rejection. The degree of flux decline was found to be dependent upon the combination of permeate drag force and physico-chemical properties of the membranes. The membranes with higher permeability generally displayed faster initial flux decline. In addition, hydrophobic and rough membranes exhibited a higher flux decline and lower chemical cleaning efficiency than smooth and/or hydrophilic membranes. Flux decline experiments, in situ microscopic techniques, analysis of elemental composition and functional groups revealed that the pretreatment including microfiltration, pH adjustment and addition of antiscalants could alleviate membrane fouling significantly. Chemical cleaning using caustic and anionic surfactant solutions restored membrane permeability more efficiently than hydraulic cleaning or using acids and metal chelating agents. This study showed that TFC-ULP, TMG-10, and NF-90 membranes exhibited competitive efficiency regarding salt rejection, iodide recovery and adjusted specific flux as compared to a conventional RO membrane.

Mucormycosis is the third invasive mycosis in order of importance after candidiasis and aspergillosis and is caused by fungi of the class Zygomycetes. The most important species in order of frequency is Rhizopus arrhizus (oryzae). Identification of the agents responsible for mucormycosis is based on macroscopic and microscopic morphological criteria, carbohydrate assimilation and the maximum temperature compatible with its growth. The incidence of mucormycosis is approximately 1.7 cases per 1000 000 inhabitants per year, and the main risk-factors for the development of mucormycosis are ketoacidosis (diabetic or other), iatrogenic immunosuppression, use of corticosteroids or deferoxamine, disruption of mucocutaneous barriers by catheters and other devices, and exposure to bandages contaminated by these fungi. Mucorales invade deep tissues via inhalation of airborne spores, percutaneous inoculation or ingestion. They colonise a high number of patients but do not cause invasion. Mucormycosis most commonly manifests in the sinuses (39%), lungs (24%), skin (19%), brain (9%), and gastrointestinal tract (7%), in the form of disseminated disease (6%), and in other sites (6%). Clinical diagnosis of mucormycosis is difficult, and is often made at a late stage of the disease or post-mortem. Confirmation of the clinical form requires the combination of symptoms compatible with histological invasion of tissues. The probable diagnosis of mucormycosis requires the combination of various clinical data and the isolation in culture of the fungus from clinical samples. Treatment of mucormycosis requires a rapid diagnosis, correction of predisposing factors, surgical resection, debridement and appropriate antifungal therapy. Liposomal amphotericin B is the therapy of choice for this condition. Itraconazole is considered to be inappropriate and there is evidence of its failure in patients suffering from mucormycosis. Voriconazole is not active in vitro against Mucorales, and failed when used in vivo. Posaconazole and ravuconazole have good activity in vitro. The overall rate of mortality of mucormycosis is approximately 40%.

Stable attachment of 64Cu2+ to a targeting molecule usually requires the use of a bifunctional chelator (BFC). Sarcophagine (Sar) ligands rapidly coordinate 64Cu2+ within the multiple macrocyclic rings comprising the cage structure under mild conditions, providing high stability in vivo. Previously, we have designed a new versatile cage-like BFC Sar ligand, 4-((8-amino-3,6,10,13,16,19-hexaazabicyclo[6.6.6]icosane-1-ylamino)methyl)benzoic acid (AmBaSar), for 64Cu radiopharmaceuticals. Here we report the improved synthesis of AmBaSar, 64Cu2+ labeling conditions and its biological evaluation compared with the known BFC 1,4,7,10-tetraazacyclododecane-N,N′,N″,N‴-tetraacetic acid (DOTA).The AmBaSar was synthesized in four steps starting from (1,8-diamine-Sar) cobalt(III) pentachloride ([Co(DiAmSar)]Cl5) using an improved synthetic method. The AmBaSar was labeled with 64Cu2+ in pH 5.0 ammonium acetate buffer solution at room temperature, followed by analysis and purification with HPLC. The in vitro stability of 64Cu-AmBaSar complex was evaluated in phosphate buffered saline (PBS), fetal bovine serum and mouse blood. The microPET imaging and biodistribution studies of 64Cu-AmBaSar were performed in Balb/c mice, and the results were compared with 64Cu-DOTA.The AmBaSar was readily prepared and characterized by MS and 1H NMR. The radiochemical yield of 64Cu-AmBaSar was ≥98% after 30 min of incubation at 25°C. The 64Cu-AmBaSar complex was analyzed and purified by HPLC with a retention time of 17.9 min. The radiochemical purity of 64Cu-AmBaSar was more than 97% after 26 h of incubation in PBS or serum. The biological evaluation of 64Cu-AmBaSar in normal mouse demonstrated renal clearance as the primary mode of excretion, with improved stability in vivo compared to 64Cu-DOTA.The new cage-like BFC AmBaSar was prepared using a simplified synthetic method. The 64Cu-AmBaSar complex could be obtained rapidly with high radiochemical yield (≥98%) under mild conditions. In vitro and in vivo evaluation of AmBaSar demonstrated its promising potential for preparation of 64Cu radiopharmaceuticals.

Preparation par deux methodes: 1) etherification par transfert de phase d'un polymere α,ω dielectrophile avec la p-hydroxyphenyl-2 oxazoline-2(I) 2) extension de chaine par transfert de phase d'un polymere α,ω diphenol avec le chlorure de methylene (II) ou polyetherification d'un bisphenol avec (II) en presence de (I)