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ABSTRACT Particulate compositions including elemental carbon (EC), organic carbon (OC), water-soluble ionic species, and elemental compositions were investigated during the period from 2004 to 2006 in southern Taiwan. The correlation [...]

Tetrathiomolybdate (TM) is an orally active agent for treatment of disorders of copper metabolism. Here we describe how TM inhibits proteins that regulate copper physiology. Crystallographic results reveal that the surprising stability of the drug complex with the metallochaperone Atx1 arises from formation of a sulfur-bridged copper-molybdenum duster reminiscent of those found in molybdenum and iron sulfur proteins. Spectroscopic studies indicate that this cluster is stable in solution and corresponds to physiological dusters isolated from TM-treated Wilson's disease animal models. Finally, mechanistic studies show that the drug-metallochaperone inhibits metal transfer functions between copper-trafficking proteins. The results are consistent with a model wherein TM can directly and reversibly down-regulate copper delivery to secreted metalloenzymes and suggest that proteins involved in metal regulation might be fruitful drug targets. 10.1126/science.1179907

Some disinfectants have been demonstrated to be effective against surface mold growth and/or viruses responsible for the spread of common respiratory infections. Antimicrobial efficacy of green cleaning products has generally not been established in these areas. In this survey, the author found that out of 27 products approved by Green Seal as hard surface cleaners, 26 do not claim antimicrobial capability. While some contained hydrogen peroxide, a compound with limited spectrum disinfection capabilities, only one was registered with the U.S. Environmental Protection Agency as antimicrobial. The need for additional research and documentation is discussed., Introduction Since the 19th century, the "germ theory of disease" (Pasteur, 1880) has encouraged cleaning practices that minimize levels of surface pathogens. Introduction of the concept of "green" cleaning represents [...]

Although colonic lumen N[H.sub.4.sup.+] levels are high, 15-44 mM normal range in humans, relatively few studies have addressed the transport mechanisms for [H.sub.4.sup.+]. More extensive studies have elucidated the transport of N[H.sub.4.sup.+] in the kidney collecting duct, which involves a number of transporter processes also present in the distal colon. Similar to N[H.sub.4.sup.+] secretion in the renal collecting duct, we show that the distal colon secretory model, T84 cell line, has the capacity to secrete [H.sub.4.sup.+] and maintain an apical-to-basolateral N[H.sub.4.sup.+] gradient. N[H.sub.4.sup.+] transport in the secretory direction was supported by basolateral N[H.sub.4.sup.+] loading on NKCCl, [Na.sup.+]-[K.sup.+]-ATPase, and the N[H.sub.4.sup.+] transporter, RhBG. [H.sub.4.sup.+] was transported on NKCC1 in T84 cells nearly as well as [K.sup.+] as determined by bumetanide-sensitive [sup.86]Rb-uptake. [sup.86]Rb-uptake and ouabain-sensitive current measurement indicated that N[H.sub.4.sup.+] is transported by [Na.sup.+]-[K.sup.+]-ATPase in these cells to an equal extent as [K.sup.+]. T84 cells expressed mRNA for the basolateral N[H.sub.4.sup.+] transporter RhBG and the apical N[H.sub.4.sup.+] transporter RhCG. Net N[H.sub.4.sup.+] transport in the secretory direction determined by [sup.14]C-methylammonium (MA) uptake and flux occurred in T84 cells suggesting functional RhG protein activity. The occurrence of N[H.sub.4.sup.+] transport in the secretory direction within a colonic crypt cell model likely serves to minimize net absorption of N[H.sub.4.sup.+] because of surface cell N[H.sub.4.sup.+] absorption. These findings suggest that we rethink the present limited understanding of N[H.sub.4.sup.+] handling by the distal colon as being due solely to passive absorption. RhBG; RhCG; colon; hyperammonemia

The Amt proteins constitute a ubiquitous family of transmembrane ammonia channels that permit the net uptake of ammonium by cells. In many organisms, there is more than one amt gene, and these genes are subjected to nitrogen control. The mature Amt protein is a homo- or heterooligomer of three Amt subunits. We previously characterized an amt1 gene in the unicellular cyanobacterium Synechococcus elongatus strain PCC 7942. In this work, we describe the presence in this organism of a second amt gene, amtB, which encodes a protein more similar to the bacterial AmtB proteins than to any other characterized cyanobacterial Amt protein. The expression of amtB took place in response to nitrogen step-down, required the NtcA transcription factor, and occurred parallel to the expression of amt1. However, the transcript levels of amtB measured after 2 h of nitrogen deprivation were about 100-fold lower than those of amt1. An S. elongatus amtB insertional mutant exhibited an activity for uptake of [[sup.14]C]methylammonium that was about 55% of that observed in the wild type, but inactivation of amtB had no noticeable effect on the uptake of ammonium when it was supplied at a concentration of 100 [micro]M or more. Because an S. elongatus amt1 mutant is essentially devoid of [[sup.14]C] methylammonium uptake activity, the mature Amt transporter is functional in the absence of AmtB subunits but not in the absence of Amt1 subunits. However, the S. elongatus amtB mutant could not concentrate [[sup.14]C]methylammonium within the cells to the same extent as the wild type. Therefore, AmtB is necessary for full methylammonium uptake activity in S. elongatus.

Byline: Munish. Garg, Tinku. Singhal, Hitender. Sharma Objective: The objective of this study was to evaluate the cardioprotective effect of herbal bioactive compound ammonium glycyrrhizinate against doxorubicin-induced cardiomyopathy, in experimental [...]