The Influence of Citrate, Maltolate and Fluoride on the Gastrointestinal Absorption of Aluminum at a Drinking Water-Relevant Concentration: A \u3csup\u3e26\u3c/sup\u3eAl and \u3csup\u3e14\u3c/sup\u3eC Study

The objectives were to test the null hypotheses that (1) citrate, maltolate, and fluoride do not significantly influence oral Al bioavailability, Cmax or Tmax at an Al dose relevant to drinking water exposure; and (2) Al citrate and maltolate are absorbed intact from the gastrointestinal tract. Male Fisher rats were given 1 ml of solution intra-gastrically containing 1 nCi 26Al (65 nmol total Al) as the Al3+ ion, or as complexes with 14C-citrate, 14C-maltolate or fluoride, during concurrent 27Al iv infusion. Blood was repeatedly collected for serum 26Al, total Al and 14C quantification. Absorption parameters were estimated using WinNonlin. Al bioavailability, Cmax and Tmax from the ion, citrate, maltolate, and fluoride were 0.29 ± 0.11%, 0.61 ± 0.31%, 0.50 ± 0.25%, and 0.35 ± 0.10%; 659 ± 195, 1073 ± 250, 881 ± 356, and 880 ± 295 fg/ml; and 1.2 ± 0.9, 1.0 ± 1.1, 1.3 ± 1.0, and 1.0 ± 0.9 h (X ± SD) respectively. Serum 14C was ∼100 times higher than 26Al. The results suggest a non-significant enhancement of oral Al bioavailability by citrate and maltolate, some Al complex dissociation in the GI tract, and less absorption of Al than citrate or maltolate. The presence of citrate, maltolate and fluoride, at a similar molar concentration to Al, would not be expected to greatly influence Al absorption from drinking water

Removing Aluminum from Solution Using Chelating Compounds and Immobilized Tethered Chelators

Methods are described for removing aluminum from a solution using novel di- and tripodal compounds as chelators

Chelating Compounds and Immobilized Tethered Chelators

Novel di- and tripodal compounds useful as chelators, intermediates for their production and a method for treating an aqueous solution to remove trivalent metal ions are presented

Chelating Compounds and Immobilized Tethered Chelators

Novel compounds useful as chelators, intermediates for their production and methods for removing trivalent and tetravalent metal ions from solution are presented.https://irl.umsl.edu/patents/1063/thumbnail.jp

A Filtration System That Greatly Reduces Aluminum in Calcium Gluconate Injection, USP Used to Prepare Parenteral Nutrition Solutions

OBJECTIVE: The study objective was to reduce aluminum (Al) in Calcium Gluconate Injection, US Pharmacopeia (USP) used in the preparation of parenteral nutrition (PN) solutions. METHODS: A flow-through filter containing an immobilized chelator that complexes Al from Calcium Gluconate Injection, USP as it flows through the filter was designed, refined by design modifications, and extensively tested. When a small-volume parenteral vial containing 100 mL of Calcium Gluconate Injection, USP is connected on the inlet side of the filter, and the outlet side is connected to an evacuated receiving vial, the filtered solution is drawn into the receiving vial. This constitutes a complete system to remove Al from Calcium Gluconate Injection, USP. RESULTS: The extent of Al removal is flow rate dependent. At a flow rate of 1 mL/min approximately 85% of the Al was removed from calcium gluconate solution. PN solutions have been reported to deliver 15 to 23 mcg/kg/day Al to neonates. Given that Calcium Gluconate Injection, USP provides 85% of the Al in neonatal PN solutions, removal of 85% of the Al from this source was calculated to reduce Al delivered to most neonates to \u3c 5 mcg/kg/day. CONCLUSIONS: A point-of-use, self-contained, single-use, disposable, Al-complexing filter has been created. It was calculated to reduce Al delivered in PN solutions by 72%, resulting in daily Al delivery below the level that results in Al accumulation associated with central nervous system and bone toxicity to all but the smallest (\u3c 1 kg) infants

Flow-Through Filter to Remove Aluminum from Medical Solutions

A flow through filter assembly includes a trivalent and tetravalent metal ion capturing agent and a flow controller providing a predetermined flow rate which allows capture of the trivalent and tetravalent metal ions by the capturing agent

Fenfluramine and N-ethyl amphetamine: Comparison of the reinforcing and rate-decreasing actions in the rhesus monkey

N-ethyl amphetamine HCl (NEA) and fenfluramine HCl ( meta -trifluoromethyl N-ethyl amphetamine) were evaluated as reinforcers in rhesus monkeys that had been previously trained to press a lever using food presentations and cocaine HCl injections as reinforcers. Each daily session consisted of episodic opportunities to obtain reinforcers under a fixed-ratio schedule of 30. A drug period was interpolated between two periods in which lever-press responding was maintained by food presentations. Compared to saline, none of the drugs altered the rate of responding in the food periods which preceded the drug sessions, indicating the absence of residual response-disrupting drug actions from previous sessions. However, NEA and fenfluramine self-injection resulted in dose-related decreases in response rates during the food periods which immediately followed the drug sessions. Cocaine HCl (30 Μg/kg/injection) maintained high response rates at over one response/second during the drug periods, as did the same dose of NEA. Doses of 10 and 100 Μg/kg/injection of NEA as well as all doses of fenfluramine HCl (10 through 300 Μg/kg/injection) maintained rates that were not different from those associated with saline injections. These results substantiate and extend earlier findings with fenfluramine and indicate that its failure to act as a reinforcer is attributable to its meta -trifluoromethyl group.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46392/1/213_2004_Article_BF00429257.pd

The reinforcing property of ethanol in the rhesus monkey

Rhesus monkeys received intravenous injections of ethanol during daily sessions contingent on their presses on an available lever. Under the standard conditions, when each response on the lever during a 3-h period each day resulted in an i.v. injection of 0.1 g/kg ethanol, the monkeys made between 30 and 50 responses/session and developed blood ethanol levels of approximately 400 mg%. Under this and other conditions of response-contingent delivery of ethanol, a negatively accelerated pattern of self-injection within sessions was demonstrated. Variations in the dose per injection (0.05–0.2 g/kg/injection) resulted in changes in the rate of lever-pressing; the number of self-injections was inversely related to dose. Ethanol intake increased only slightly with increased dose per injection. Noncontingent administration of various doses of i.v. ethanol immediately prior to a daily session decreased the number of responses; the total amount of ethanol administered (contingent plus noncontingent), however, remained constant over a pretreatment dose range of 1 to 3 g/kg. When access time to ethanol was increased from 3 to 6 h/day, the total amount of ethanol taken increased slightly. However, the blood ethanol levels at the end of a 6-h session closely approximated those obtained following 3-h sessions, indicating that during the last 3–4 h of the 6-h sessions, the rate of ethanol intake closely matched the rate of ethanol elimination.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46404/1/213_2004_Article_BF00426785.pd