objectives: this study aimed to assess the effect of re-etching of desensitized dentin for five and 10 seconds on marginal microleakage of composite restorations. materials and methods: class v cavities (4x2x2mm) were prepared on the buccal surfaces of 64 third molars and randomly divided into four groups of 16. in the control group, single bond (sb) adhesive was applied after etching. in bb+sb...

Sponges, which constitute the phylum Porifera, are the most primitive of the multicellular animals, among all marine organisms screened. Marine sponges produce the largest number of structurally diversified natural products. In this study we investigated in vitro antimicrobial activity of Ircinia mutans collected from the Kish Island in the Persian Gulf against strains of bacteria Escherichia c...

Escherichia coli is commonly isolated from the urine of kidney stone patients and has been observed to be embedded within the nidus of calcium oxalate kidney stones. A possible association between urinary tract infections and calcium oxalate crystallogenesis was investigated using an agarose plate assay. Calcium oxalate crystallization was observed to be directly proportional to the density of ...

In the title hydrated mol-ecular salt, C(4)H(14)N(2)O(2+)·C(2)O(4) (2-)·H(2)O, the oxalate dianion is almost planar (r.m.s. deviation = 0.020 Å). In the crystal, the components are linked by N-H⋯O(water), N-H⋯O(oxalate) O-H(ammonium)⋯O(oxalate), O-H(water)⋯O(oxalate) and O-H(water)⋯O(ammonium) hydrogen bonds, thereby forming a complex three-dimensional packing motif.

Oxalate oxidase catalyzes the conversion of oxalic acid and molecular oxygen to carbon dioxide and hydrogen peroxide. Oxalate-degrading enzymes are of interest for various applications including clinical analysis of the levels of oxalic acid in blood and urine and control of oxalic acid in industrial processes, such as pulp and paper manufacture. In these applications, the presence of oxyanions...

Formation of thiazolidine-2,4-dicarboxylic acid, the L-cysteine-glyoxylate adduct, is the putative mechanism by which L-cysteine reduces hepatic oxalate production from glycollate [Bais, Rofe and Conyers (1991) J. Urol. 145, 1302-1305]. This was investigated in isolated rat hepatocytes by the simultaneous measurement of both adduct and oxalate formation. Different diastereoisomeric ratios of ci...

1. Freshly voided urine from healthy subjects was pooled and ultrafiltered (10,000 daltons). The ultrafiltrable and the macromolecular portions were preincubated with calcium oxalate, uric acid and sodium urate crystals and the effects on the inhibitory activity of calcium oxalate crystal growth assessed by monitoring the disappearance of [14C]oxalate from the solution. 2. The inhibitory activi...