Oxalate interactions

Coriander Coriandrum sativum) Uses t Appetite, treat D, dyspep-sia, flatulence Action Stimulates gastric secretions, spasmolytic effects Available forms Tine 10-30 gtts PO OD Contra w/ PRG or lactation Notes/SE N/V, fatty liver tumors, allergic skin Rxns Interactions T Effects OF oral hypoglycemics EMS T Risk of photosensitivity Rxns may cause hypoglycemia Cranberry [Vaeeinium macreearpon) Uses Prevention UTI urinary deodorizer in urinary incontinence Actions Interferes w/ bacterial adherence to epithelial cells of the bladder Available forms Caps 300-500 mg PO bid-qid unsweetened juice 8-16 oz daily tine 3-5 mL or tincture 1/2-1 tsp up to 3X/d, tea 2-3 tsps of dried flowers/cup creams apply topically 2-3X/d PO SE D, irritation, nephrolithiasis if T urinary Ca oxalate Interactions T Effects OF warfarin ... 

Two nucleation processes important to many people (including some surface scientists ) occur in the formation of gallstones in human bile and kidney stones in urine. Cholesterol crystallization in bile causes the formation of gallstones. Cryotransmission microscopy (Chapter VIII) studies of human bile reveal vesicles, micelles, and potential early crystallites indicating that the cholesterol crystallization in bile is not cooperative and the true nucleation time may be much shorter than that found by standard clinical analysis by light microscopy [75]. Kidney stones often form from crystals of calcium oxalates in urine. Inhibitors can prevent nucleation and influence the solid phase and intercrystallite interactions [76, 77]. Citrate, for example, is an important physiological inhibitor to the formation of calcium renal stones. Electrokinetic studies (see Section V-6) have shown the effect of various inhibitors on the surface potential and colloidal stability of micrometer-sized dispersions of calcium oxalate crystals formed in synthetic urine [78, 79]. 

The commonest staining trouble is iron stain —the blue-black stain caused by the interaction of soluble iron corrosion products and the natural tannins in wood. Hardwoods are generally more susceptible than softwoods. Steel wool should not be used for smoothing wood surfaces. Iron stains, if not too severe, can be removed with oxalic acid. Heavy contamination with soluble iron corrosion products usually results in migration and conversion to rust deposits in the wood. 

EDTA, leading to a postulate that more than one equivalent of Ca2+ can be captured by X (e.g. one Ca2+ sequestered by the three amines and the three carboxylates and another Ca2 + by the remaining half the donor groups), as the Dreiding model suggests. The fact that there was no interaction at neutral pH of X with phosphate or oxalate anions was separately confirmed. Thus, the dissolution of Ca3(P04)2 and Ca(C204) is entirely due to the cation complexation mechanism. 

P. Behrend HO.NH.CO.C(OH) N.OH, unknown in the free state, but several of its salts were prepd and proved to be expl (Ref 3). Ba(C2H304N2)2 mp, explds violently was prepd by the interaction of ethyl oxalate, Ba hydroxide soln and hydioxylaminohydiochloride. Ca, Cu and Ag salts were also prepd they all expld at about 50°... 

To understand how these parameters affected the efficiency of the chemiluminescent reaction, we examined the mechanism originally proposed by Rauhut (26). As shown in Scheme 2, hydrogen peroxide reacts with an oxalate ester, such as 2,4,6-trichlorophenyl oxalate (TCPO), in a two-step process to form a reactive intermediate for which Rauhut suggested structure 1, the 1,2-dioxetanedione. The dioxetanedione then interacts with an acceptor (ACC) to produce two molecules of COj and the excited state of the acceptor. The last stage of the sequence is fluorescence emission from the acceptor. 

Janos, P., Separation of some metals as their anionic oxalate complexes by reversed-phase ion-interaction chromatography, /. Chromatogr., 635, 257,1993. 

The effects of organic molecules and phosphate on the adsorption of acid phosphatase on various minerals, and kaolinite in particular, have been investigated by Huang et al. [97]. The Langmuir affinity constant for AcP adsorption by kaolinite follows the series tartrate (K — 97.8) > phosphate (K= 48.6) > oxalate (K — 35.6) > acetate (K= 13.4). At low concentration, acetate even promoted the adsorption of acid phosphatase. It was considered that competitive interactions between anionic adsorbates can occur directly through competition for surface sites and indirectly through effects of anion adsorption on the surface charge and protonation. 

The most commonplace substrates in energy-transfer analytical CL methods are aryl oxalates such as to(2,4,6-trichlorophenyl) oxalate (TCPO) and z s(2,4-dinitrophenyl) oxalate (DNPO), which are oxidized with hydrogen peroxide [7, 8], In this process, which is known as the peroxyoxalate-CL (PO-CL) reaction, the fluorophore analyte is a native or derivatized fluorescent organic substance such as a polynuclear aromatic hydrocarbon, dansylamino acid, carboxylic acid, phenothiazine, or catecholamines, for example. The mechanism of the reaction between aryl oxalates and hydrogen peroxide is believed to generate dioxetane-l,2-dione, which may itself decompose to yield an excited-state species. Its interaction with a suitable fluorophore results in energy transfer to the fluorophore, and the subsequent emission can be exploited to develop analytical CL-based determinations. 

In most terrestrial plant-pathogen interactions a diphenylene-iodonium (DPI)-sensitive (O Donnell et al. 1993), membrane-located, and receptor-activated NADPH oxidase generates superoxide radicals (Levine et al. 1994 Doke and Miura 1995 Lamb and Dixon 1997 Bolwell et al. 1998), which eventually dis-mutate into H202 and 02 (Sutherland 1991). Apoplastic peroxidases (Bolwell et al. 1998 Martinez et al. 1998), as well as various oxidases such as oxalate oxidase (Zhang et al. 1995 Thordal-Christensen et al. 1997) or amine oxidase (Laurenzi et al. 2001 Rea et al. 2002), have also been identified as sources of ROS in higher plants. 

Table 2 summarizes the numerical results on average intermolecular/interi-onic 0---0 and intramolecular/intra-ionic C-0 structural parameters for the [COOH]n---[COOH]n, [COOH]a---[COOH]a and [COOH]A---[COO]A inter-molecular interactions, together with those obtained for the [COOH] A- [COO ]A sample in the case of the hydrogen oxalate anion. Data were retrieved from the CSD with a cut-off distance on 0-"0 separations of 3.0 A. A visual prospect of the data listed in column III is provided in Fig. 6, where histograms of intramolecular C-0 distances within the protonated and deprotonated COOH/COO groups are presented. 

The interaction between calcium malate and ammonium oxalate results into an equivalent quantity of calcium oxalate by displacement mechanism which is subsequently precipitated ... 

Oxalaies. The interaction of phenylbiguanide and diethyl oxalate presents certain anomalous features (485). In methanol at 10°, the reactants produce an immediate quantitative precipitate of a yellow compound Y", of composition CioHqNsOz. Continued reaction at room temperature slowly yields 2-metoxycarbonylphenylguanamine (CXV) and is complete after six days. These experimental results were confirmed independently by Italian investigators (536). 

On the interaction of 1,3-diketones with dihydrazides of oxalic and malo-nic acids, the condensation products have been obtained in a molar ratio of 2 1 (88ZOR1823). In the solid state, they exist as the bispyrazolines 77 but in solution, equilibria are observed. These equilibria occur with the participation of the bispyrazoline tautomer, involving two diastereomers, and also of tautomers containing hydrazone and/or enhydrazine fragments. 

When particles or large molecules make contact with water or an aqueous solution, the polarity of the solvent promotes the formation of an electrically charged interface. The accumulation of charge can result from at least three mechanisms (a) ionization of acid and/or base groups on the particle s surface (b) the adsorption of anions, cations, ampholytes, and/or protons and (c) dissolution of ion-pairs that are discrete subunits of the crystalline particle, such as calcium-oxalate and calcium-phosphate complexes that are building blocks of kidney stone and bone crystal, respectively. The electric charging of the surface also influences how other solutes, ions, and water molecules are attracted to that surface. These interactions and the random thermal motion of ionic and polar solvent molecules establishes a diffuse part of what is termed the electric double layer, with the surface being the other part of this double layer. 

Calcium ion interactions with calmodulin, THERMODYNAMIC CYCLES Calcium oxalate,... 

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