Preferred orientation in an angled intercalation site of a chloro-substituted lambda- [Ru(TAP)2(dppz)]2+ complex bound to d(TCGGCGCCGA)2

The crystal structure of the ruthenium DNA ‘light-switch’ complex -[Ru(TAP)2(11-Cl-dppz)]2+ (TAP = tetraazaphenanthrene, dppz = dipyrido[3,2-a':2',3'-c]phenazine)) bound to the oligonucleotide duplex d(TCGGCGCCGA)2 is reported. The synthesis of the racemic ruthenium complex is described for the first time, and the racemate was used in this study. The crystal structure, at atomic resolution (1.0 Å), shows one ligand as a wedge in the minor groove, resulting in the 51 kinking of the double helix, as with the parent lambda-[Ru(TAP)2(dppz)]2+. Each complex binds to one duplex by intercalation of the dppz ligand and also by semi-intercalation of one of the orthogonal TAP ligands into a second symmetrically equivalent duplex. The 11-Cl substituent binds with the major component (66%) oriented with the 11-chloro substituent on the purine side of the terminal step of the duplex.

Genotyping, physiological features and proteolytic activities of a potentially pathogenic Acanthamoeba sp isolated from tap water in Brazil

Acanthamoeba spp., known to cause keratitis and granulomatous encephalitis in humans, are frequently isolated from a variety of water sources. Here we report for the first time the characterization of an Acanthamoeba sp. (ACC01) isolated from tap water in Brazil. This organism is currently being maintained in an axenic growth medium. Phylogenetic analysis based on SSU rRNA gene sequences positioned the new isolate in genotype T4, closest to the keratitis-causing isolate, A. polyphaga ATCC 30461 (similar to 99% similarity). Acanthamoeba ACC01 and A. polyphaga 30461 both grew at 37 degrees C and were osmotically resistant, multiplying in hyperosmolar medium. Both isolates secreted comparable amounts of proteolytic enzymes, including serine peptidases that were optimally active at a near neutral/alkaline pH and resolved identically in gelatin gels. Incubation of gels at pH 4.0 with 2 mM DTT also indicated the secretion of similar cysteine peptidases. Altogether, the results point to the pathogenic potential of Acanthamoeba ACC01. (C) 2009 Elsevier Inc. All rights reserved.

Risk assessment of trihalomethanes from tap water in Fortaleza, Brazil

The cancer risks (CR) by oral ingestion, dermal absorption, and inhalation exposure of trihalomethanes (THM) from tap water of ten districts in Fortaleza, Brazil were estimated. The mean levels of THM compounds were obtained in Fortaleza tap water as follow: 63.9 mu g L(-1) for chloroform (CHCl(3)), 40.0 mu g L(-1) for bromodichloromethane (CHBrCl(2)), and 15.6 mu g L(-1) for dibromochloromethane (CHBr(2)Cl). Bromoform (CHBr(3)) was not detected. The mean CR for THMs in tap water is 3.96 x 10(-4). The results indicate that Fortaleza residents have a higher CR by inhalation than dermal absorption and oral ingestion. The CR for CHCl(3) contributes with 68% as compared with the total CR, followed by CHBrCl(2) (21%), and CHBr(2)Cl (11%). The hazard index (HI) is about ten times lower than unity, not indicating non-cancer effects.

Um método eficiente para resolução do problema de Despacho Ótimo de Reativos com controle discreto do TAP dos transformadores

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Voltammetric sensor for simultaneous determination of p-phenylenediamine and resorcinol in permanent hair dyeing and tap water by composite carbon nanotubes/chitosan modified electrode

p-Phenylenediamine (PPD) and resorcinol (RSN) are hair dye precursors of permanent dyeing more used worldwide. The present work describes a simple and economic voltammetric sensor for simultaneous determination of both components in commercial hair dyeing and tap water at low concentrations. PPD and RSN are oxidized at + 0.17 and + 0.61 V vs. Ag/AgCl at glassy carbon electrode coated by composites of multiwall carbon nanotubes with chitosan (MWNTs-CHT/GCE), which anodic currents density normalized are 10% and 70% higher in relation to the unmodified electrode, respectively. The calibration curve for simultaneous determination of PPD and RSN showed linearity between 0.55 and 21.2 mg L-1 with detection limits of 0.79 and 0.58 mg L-1 to PPD and RSN, respectively. The relative standard deviations found for ten determinations were of 0.73 and 2.35% to 2.70 mg L-1, and 0.87 and 1.08% to 15.96 mg L-1 to PPD and RSN, respectively. The voltammetric sensor was applied to determination of PPD and RSN in tap water and commercial hair dyeing samples and the average recovery for these samples was around 97%. The products generated from PPD and RSN reaction such as was p-quinonediimine and bandrowski base were detected by LC-MS/MS and UV-vis spectrophotometry. (C) 2014 Published by Elsevier B.V.

Tap-Off Power From the Overhead Shield Wires of an HV Transmission Line

In recent years, there was an increase of ancillary service loads, such as signaling systems, inspection robots, surveillance cameras, and other monitoring devices distributed along high-voltage transmission lines which require low-power dc voltage supplies. This paper investigates the use of the induced voltage in the shield wires of an overhead 525 kV transmission line as a primary power source. Since phase current variations throughout the day affect the induced voltage in the overhead ground wire, a step-down dc-dc converter is used after rectification of the ac voltage to provide a regulated dc output voltage. The initial encouraging results obtained indicate that this form of power supply can be a feasible and cost-effective alternative for feeding small ancillary service loads. The simulation results are validated by field measurements as well as the installation of a 200 W voltage stabilization system prototype.

Irrigation of continent catheterizable ileal pouches: tap water can replace sterile solutions because it is safe, easy, and economical

Continent catheterizable ileal pouches require regular irrigations to reduce the risk of bacteriuria and urinary tract infections (UTIs).

Regulatory mechanism of the light-activable allosteric switch LOV-TAP for the control of DNA binding: a computer simulation study

The spatio-temporal control of gene expression is fundamental to elucidate cell proliferation and deregulation phenomena in living systems. Novel approaches based on light-sensitive multiprotein complexes have recently been devised, showing promising perspectives for the noninvasive and reversible modulation of the DNA-transcriptional activity in vivo. This has lately been demonstrated in a striking way through the generation of the artificial protein construct light-oxygen-voltage (LOV)-tryptophan-activated protein (TAP), in which the LOV-2-Jα photoswitch of phototropin1 from Avena sativa (AsLOV2-Jα) has been ligated to the tryptophan-repressor (TrpR) protein from Escherichia coli. Although tremendous progress has been achieved on the generation of such protein constructs, a detailed understanding of their functioning as opto-genetical tools is still in its infancy. Here, we elucidate the early stages of the light-induced regulatory mechanism of LOV-TAP at the molecular level, using the noninvasive molecular dynamics simulation technique. More specifically, we find that Cys450-FMN-adduct formation in the AsLOV2-Jα-binding pocket after photoexcitation induces the cleavage of the peripheral Jα-helix from the LOV core, causing a change of its polarity and electrostatic attraction of the photoswitch onto the DNA surface. This goes along with the flexibilization through unfolding of a hairpin-like helix-loop-helix region interlinking the AsLOV2-Jα- and TrpR-domains, ultimately enabling the condensation of LOV-TAP onto the DNA surface. By contrast, in the dark state the AsLOV2-Jα photoswitch remains inactive and exerts a repulsive electrostatic force on the DNA surface. This leads to a distortion of the hairpin region, which finally relieves its tension by causing the disruption of LOV-TAP from the DNA.

TAP deficiency syndrome: chronic rhinosinusitis and conductive hearing loss

Nose-ear-throat manifestations of immunodeficiency disorders represent a diagnostic challenge for clinicians as these diseases often constitute the initial sign for connective disorders or autoimmune disease. The history of chronic rhinosinusitis and conductive hearing loss is often non specific. Therefore attention to an HLA class I deficiency must be considered if the disease has not been diagnosed on routine examination. One of the syndromes is due to a defective TAP complex, the peptide transporter complex associated with antigen presentation. Herein, we report two sisters with TAP-deficiency. The treatment of choice for TAP-deficient patients is conservative.