Acidic macromolecules inhibit calcium oxalate nucleation, growth, aggregation and attachment to cells in vitro. To test for such an effect in vivo we used osmotic minipumps to continuously infuse several doses of the 5.1 kDa poly(acrylic acid) (pAA(5.1)) into rats fed a diet which causes renal calcium oxalate crystal deposition. Although kidneys of rats receiving the saline control contained calcium oxalate crystals, measured by polarized light microscopy, those of animals given pAA(5.1) had significantly lower numbers of crystals in various zones of the kidney. Delivery of pAA(5.1) to urine was confirmed by measuring excretion of infused biotinylated pAA(5.1). Both the derivatized and unlabelled pAA(5.1) had the same effects on crystallization in vitro. Our study shows that acidic polymers hold promise as effective therapies for kidney stones likely through prevention of calcium oxalate crystal aggregate formation.

The ability of microbial populations to mediate the anaerobic transformation of six aromatic compounds in sedi ments from the Milwaukee Harbor, Green Bay, and Lake Erie was examined Sediment slurries were incubated in an anaerobic mineral salts medium that was amended with multiple electron acceptors, including manganese(IV) and Fe(III) oxides, and the concentrations of the aromatic substrates were followed over a six to 18 month period Most sediment samples showed a com plete loss of benzoate and 4 hydroxybenzoate within approximately two months Benzoate losses were partially to markedly inhibited by the addition of molybdate, whereas losses of 4 hydroxybenzoate were not molybdate inhibited Significant losses of aniline, 3 chlorobenzoate, and 2,4‐dichlorophenoxyacetic acid were observed with many of the sediments after approximately 18 months Molybdate markedly inhibited the metabolism of 3 chlorobenzoate with all sediments, and of aniline with some sed lments Increases in free chloride, which are indicative of reductive dechlorination were coincident with losses of 3 chlorobenzoate and 2,4 dichlorophenoxyacetic acid No significant metabolism of 4 chlorobenzoate was apparent in any of the sediments Over all, the results indicate that microbes with the ability to degrade at least certain aromatic compounds are present at various sites within these environments

The ability of microbial populations to mediate the anaerobic transformation of six aromatic compounds in sedi ments from the Milwaukee Harbor, Green Bay, and Lake Erie was examined Sediment slurries were incubated in an anaerobic mineral salts medium that was amended with multiple electron acceptors, including manganese(1V) and Fe(II1) oxides, and the concentrations of the aromatic substrates were followed over a six to 18 month period Most sediment samples showed a com plete loss of benzoate and 4 hydroxybenzoate within approximately two months Benzoate losses were partially to markedly inhibited by the addition of molybdate, whereas losses of 4 hydroxybenzoate were not molybdate inhibited Significant losses of aniline, 3 chlorobenzoate, and 2,4-dichlorophenoxyacetic acid were observed with many of the sediments after approximately 18 months Molybdate markedly inhibited the metabolism of 3 chlorobenzoate with all sediments, and of aniline with some sed iments Increases in free chloride, which are indicative of reductive dechlorination were coincident with losses of 3 chlorobenzoate and 2,4 dichlorophenoxyacetic acid No significant metabolism of 4 chlorobenzoate was apparent in any of the sediments Over all, the results indicate that microbes with the ability to degrade at least certain aromatic compounds are present at various sites within these environments