bluuebunny/crossref_metadata_2025 huggingface dataset:
Hydrazine and Its Derivatives
Authors: Rothgery Eugene F.
Published: November 2004

Hydrazine (diamide), N2H4, a colorless liquid having an ammoniacal odor, is the simplest diamine and unique in its class because of the NN bond.

Hydrazine and its simple methyl and dimethyl derivatives have endothermic heats of formation and high heats of combustion. Hence, these compounds are used as rocket fuels. Other derivatives are used as gas generators and explosives. Hydrazine, a base slightly weaker than ammonia, forms a series of useful salts. As a strong reducing agent, hydrazine is used for corrosion control in boilers and hot‐water heating systems; also for metal plating, reduction of noble‐metal catalysts, and hydrogenation of unsaturated bonds in organic compounds. Hydrazine is also an oxidizing agent under suitable conditions. Having two active nucleophilic nitrogens and four replaceable hydrogens, hydrazine is the starting material for many derivatives, among them foaming agents for plastics, antioxidants, polymers, polymer cross‐linkers and chain‐extenders, as well as fungicides, herbicides, plant‐growth regulators, and pharmaceuticals. Hydrazine is also a good ligand; numerous complexes have been studied. Many heterocyclics are based on hydrazine, where the rings contain from one to four nitrogen atoms as well as other heteroatoms.

The many advantageous properties of hydrazine assure continued‐commercial utility. Hydrazine is available in anhydrous form as well as aqueous solutions, typically 35, 51.2, 54.4, and 64 wt % N2H4(54.7, 80, 85, and 100% hydrazine hydrate).

The commercially feasible processes involve partial oxidation of ammonia (or urea) using hypochlorite or hydrogen peroxide. Most hydrazine is produced by some variation of the Raschig process, which is based on the oxidation of ammonia using alkaline hypochlorite.

Hydrazine is toxic and readily absorbed by oral, dermal, or inhalation routes of exposure.
Mapping nonverbal IQ in young boys with fragile X syndrome
Authors: Skinner Martie , Hooper Stephen , Hatton Deborah D. , Roberts Jane , Mirrett Penny , Schaaf Jennifer , Sullivan Kelly , Wheeler Anne , Bailey Donald B.
Published: November 2004

This study examines the developmental changes in nonverbal intellectual functioning evident in males with fragile X syndrome (FXS) measured by the Leiter International Performance Scales‐Revised (Leiter‐R). The Leiter‐R provides both IQ scores and associated growth scores which permit the examination of both age‐based IQ scores and overall intellectual growth. Participants were 45 males with full mutation FXS and ranged in age from 4.0 to 13.8 years. Each child was assessed annually using the Leiter‐R as part of a larger longitudinal battery for an average of 3.5 assessments per child and a range of 2–6 assessments, representing a total of 156 assessment occasions. Longitudinal analyzes of Leiter scores consisted primarily of hierarchical linear modeling, with the impact of chronological age, maternal education, fragile X mental retardation 1 protein (FMRP), autistic behaviors also being assessed. Findings revealed a significant linear decline in nonverbal IQ scores, with no effects of maternal education, autistic behaviors, or FMRP on mean level or rate of change in IQ scores over time. The decline slowed significantly around 8 years of age, but scores continued to decline into the 12th year of age. In contrast, a significant linear increase was observed in Leiter‐R growth scores, which was negatively influenced by autistic behaviors. The rate of increase did not change over time, and neither mean level nor rate of increase was influenced by maternal education or FMRP levels. These findings suggest that declines in IQ are the result of steady, but suboptimal intellectual growth, rather than a true deterioration in overall intellectual functioning. © 2004 Wiley‐Liss, Inc.
Congenital stationary night blindness: Report of an autosomal recessive family and linkage analysis
Authors: Abramowicz Marc J. , Ribai Pascale , Cordonnier Monique
Published: November 2004

Congenital stationary night blindness (CSNB) is a group of rare, non‐progressive conditions of the retina characterized by abnormal rod function causing impaired night vision. Among them, the Schubert–Bornschein subgroup, itself divided into a complete and an incomplete form, is characterized by a specific electrophysiological pattern. Complete, Schubert–Bornschein CSNB is usually transmitted as a monogenic trait, and most familial cases result from mutations of the NYX gene located on the X chromosome. We report a very rare family with consanguineous, first‐cousin parents, where a son and a daughter are affected with this condition, indicating autosomal recessive inheritance. As the family was too small for genome‐wide linkage, we considered several candidate loci, including the sidekick SDK1 and SDK2 genes. The latter determine lamina‐specific connectivity in the retina, a histological substrate of the ON pathway implicated in complete, Schubert–Bornschein CSNB. Although linkage was excluded in our family, observations like the present one may lead to the identification of a new molecular cause for this condition. © 2004 Wiley‐Liss, Inc.
The 2×3 Toolbox of Organometallic Methods for Regiochemically Exhaustive Functionalization
Authors: Schlosser Manfred
Published: November 2004

This Review describes a concept aimed at rational and maximal structure proliferation. To this end, simple aromatic or heterocyclic starting materials, often bulk chemicals, are converted into all regionisomerically possible polar organometallic intermediates (mostly lithiated species), which then may be combined with any of the countless electrophiles to provide attractive new building blocks, particularly functionalized derivatives. The practical implementation relies on a set (“toolbox”) of sophisticated recipes developed by mechanistically guided modification of the two most prominent exchange methods used for the generation of polar organometallic compounds: hydrogen–metal and halogen–metal interconversion. These mutant methods (“old methods in a new outfit”) amplify the existing options for organic synthesis by ensuring maximum regioflexibility. At the same time they offer new insight into factors that govern organometallic reactivity and provide hints on how to alter or finetune this reactivity judiciously.
Monitoring congenital rubella embryopathy
Authors: Rittler Monica , López‐Camelo Jorge , Castilla Eduardo E.
Published: November 2004

BACKGROUND

Currently, all developed countries include rubella vaccination in their immunization programs, targeting the complete elimination of congenital rubella syndrome (CRS). In the underdeveloped world, where this severely disabling condition still exists, only a few countries have implemented vaccination policies, and almost no data on their effectiveness or on prevalence rates are available. The aims of the present work were to search for the best phenotype to be used as a sentinel for CRS in a large series of malformed newborns and to propose a CRS surveillance system, based only on clinical data.

METHODS

A total of 43 infants diagnosed as having CRS were obtained from 19,184 multimalformed infants, ascertained by the Latin‐American Collaborative Study of Congenital Malformations, World Health Organization (WHO) Collaborating Centre for the Prevention of Birth Defects (ECLAMC), over 3,883,165 consecutive births, between 1982 and 2003. They were distributed by country and the most frequent birth defects were identified. From the 19,184 multimalformed infants, all cases presenting the birth defects identified were selected. The sensitivity, specificity, and likelihood ratio (LR) in detecting CRS were determined for these birth defects, alone and in combination. The sample size of multimalformed infants required to detect different levels of increase in the rate of CRS was determined for three sentinel phenotypes.

RESULTS

The rate of CRS was highest in Brazil. Based on the best possible combination of sensitivity, specificity, and LR, the dyad comprising eye anomalies and congenital heart defects was shown to be the most appropriate sentinel, with the lowest sample size required, to detect CRS in neonates.

CONCLUSIONS

A surveillance system for CRS, based on clinical data in newborns, is being proposed, in an attempt to monitor ongoing vaccination policies, aimed at eliminating CRS in developing countries. Birth Defects Research (Part A), 2004. © 2004 Wiley‐Liss, Inc.
Cell weight kinetics simulation in chemostat and batch culture of the rhodophyte Porphyridium cruentum
Authors: Muller‐Feuga Arnaud , Le Guédes Roland , Le Déan Loïc
Published: November 2004

Experimental observations of cell size variations in the proliferating rhodophyte Porphyridium cruentum cultured under fully controlled conditions showed significant decreases from inoculation to a steady state in the chemostat with 0.23 d−1 dilution rate and to a minimum in batch, dropping in size by ratios of over 10. To numerically simulate these variations, we assumed that the cell is made up of two categories of components that behave differently during the interphase and mitosis. These have been called essential (EC) and accessory (AC) components. It is assumed that the cell divides once the EC have doubled in size, regardless of the AC's state. The experimental cell weight time courses were correctly simulated by a model of synchronous cell kinetics based on these assumptions. The EC's specific growth rate was 1.5 times that of the whole cell, when no limitation occurred. The increase in cell weight observed during batch cultures after nutrient exhaustion was suitably simulated by assuming that EC growth stops when a limiting nutrient is exhausted. Several parameters characterizing the cell kinetics were defined, particularly the minimum minimorum EC or cell weight (26 and 15 pg for chemostat and batch, respectively), which was influenced by the cultivation method, and the maximum whole cell weight (224 to 244 pg), which depended on the inoculum's age. The influence of culture conditions on the amount of essential and accessory components contained in a cell was examined. A new approach was developed with respect to these compartments to determine the most suitable strategy and conduct a predictive approach for valuable molecule production. © 2004 Wiley Periodicals, Inc.
Protein Chemistry on the Surface of Living Cells
Authors: Johnsson Nils , George Nathalie , Johnsson Kai
Published: November 2004

The interplay between carbohydrates, lipids, and proteins determines the stability and flexibility as well as the adhesive and responsive features of the surfaces of all cells. The molecular understanding of the interactions among and between the different classes of these biomolecules is rudimentary at best, a lack of suitable experimental methods being the major reason. Here we discuss a new approach for the specific labeling of fusion proteins of carrier proteins with synthetic compounds on cell surfaces and describe how this approach can be used to investigate the properties of the labeled molecules.
Sub‐and Supercritical CO2‐Extraction of Hypericum perforatum L.
Authors: Smelcerovic A. , Lepojevic Z. , Djordjevic S.
Published: November 2004

The extraction of Hypericum perforatum L. by liquid carbon dioxide (p = 80 bar, t = 15 °C) gave almost the same extract yield (1 %, w/w) as by supercritical (p = 100 bar, t = 40 °C) carbon dioxide, containing the same percentages of essential oil (about 6.4 %, w/w). The increase of the extract yield at higher pressure (250 to 350 bar) is due to the increase of extragent density, i.e., solubility. By increasing the grinding degree of the drug, a higher extract yield is obtained in the supercritical range under high pressure. GC‐MS analysis of the extract composition showed that the non‐terpene compounds have the highest contribution. The oil content in the drug, determined by steam distillation, was 0.058 %, w/w. The oil content in the extracts, calculated for the drug, was significantly higher (1.2 to 1.9 times).
Kinetic Reaction Models for the Selective Reduction of NO by Methane over Multifunctional Zeolite‐based Redox Catalysts
Authors: Sowade T. , Schütze F.‐W. , Berndt H. , Grünert W.
Published: November 2004

Kinetic measurements of the selective catalytic reduction (SCR) of NO by methane were performed over CeO2/H‐ZSM‐5, In‐ZSM‐5, and CeO2/In‐ZSM‐5 catalysts. The parameter space covered NO, CH4, and O2 concentrations varying from 250 to 1000 ppm, from 500 to 2000 ppm, and from 0.5 to 10 vol.‐%, respectively, space velocities between 5000 and 90000 h–1 and temperatures between 573 and 873 K depending on the catalyst activities. With CeO2/In‐ZSM‐5 an additional series of measurements was performed with moistened feed gas (0.5–10 vol.‐% H2O). On the basis of a pseudo‐homogeneous, one‐dimensional fixed‐bed reactor model, the data were fitted to a kinetic model that includes power rate laws for the reduction of NO and for the unselective total oxidation of methane. From analyses of isothermal data sets, almost all reaction orders were found to vary significantly with changing temperature, which indicates that the simple kinetic model cannot reflect the complex reaction mechanism correctly. Nevertheless, the data measured with In‐ZSM‐5 could be modeled with good accuracy over a wide range of reaction temperatures (150 K) while the accuracy was less satisfactory with the remaining data sets, in particular for data with the moist feed over CeO2/In‐ZSM‐5. With the latter catalyst it was not possible to represent the data measured in dry and in moist feed in a single model even upon confinement to fixed reaction temperatures. A comparison of the separate models established showed strong changes in the reaction orders in the presence of water, which occur apparently already at a very low water content (≤ 0.5 vol.‐%). The kinetic parameters found are in agreement with earlier conclusions about the reaction mechanisms. With In‐ZSM‐5, both reaction orders and the activation energy show a rate‐limiting influence of NO oxidation on the NO reduction path which is removed by the presence of the CeO2 promoter. A difference in the reaction mechanism over CeO2/In‐ZSM‐5 and CeO2/H‐ZSM‐5 is reflected in different kinetic parameters. The differences of the kinetic parameters between dry‐feed and moist‐feed models for CeO2/In‐ZSM‐5 reflect adsorption competition between the reactants and water.
CFD Modeling of Bubble Column Reactor Including the Influence of Gas Contraction
Authors: van Baten J.M. , Krishna R.
Published: November 2004

In this paper a CFD model for a bubble column reactor undergoing a first order reaction A → B is developed. The reactor operates in the homogeneous bubbly regime and has a diameter DT = 1 m and height HT = 5 m. The incoming gas stream contains inerts, varying in proportion from 10 % to 90 %. Three‐dimensional transient Eulerian simulations were carried out for an inlet superficial gas velocity UG = 0.04 m/s. Due to the consumption of A, the gas phase suffers contraction along the height of the reactor and as a consequence there is a significant change in the gas velocity along the column height; this variation in gas velocity is stronger when the incoming gas contains a smaller proportion of inerts. The CFD simulations show that there is a considerable influence of gas contraction on both the bubble column hydrodynamics and on the reactor conversion. None of the conventionally used reactor models is capable of describing the reactor performance in the case of high gas phase contraction.
Mechanoluminscence during Wet Grinding of Fine Particles
Authors: Aman S. , Tomas J.
Published: November 2004

In stirred media mills mechanoluminescence is induced by the stressing of particles between mill beads. The light impulses accompanying the stress events are analyzed. The primary particles and aggregates exhibit a different behavior during impact loads. Mechanical stress applied to solid particles leads to the fracture of particles. Application of stress to aggregates mostly leads to the cracking of the solid bridge bonds between the primary particles. The breakage of aggregates was on‐line monitored from the time dependence of the stress frequency.
The development of the P‐CAN, a measure to operationalize the pros and cons of anorexia nervosa
Authors: Serpell Lucy , Teasdale John D. , Troop Nicholas A. , Treasure Janet
Published: November 2004

Objective

Research has suggested that a fundamental aspect of anorexia nervosa (AN) is its egosyntonic nature, the fact that it is often valued by individuals with the disorder. The current study describes the development of the P‐CAN, a quantitative measure of both positive (valued) and negative aspects of AN.

Method

Items were derived from a previous qualitative study (Serpell, Treasure, Teasdale, & Sullivan. 1999. International Journal of Eating Disorders, 25, 177–186). Data from 233 women with AN were subjected to a principal components analysis.

Results

Ten subscales were identified, six describing the pros of AN and four describing the cons of the illness.

Discussion

The P‐CAN shows good psychometric properties and should prove a useful tool for the measurement of attitudes towards AN, as well as offer insights into the maintenance of the disorder. © 2004 by Wiley Periodicals, Inc. Int J Eat Disord 36: 416–433, 2004.
Group cognitive‐behavior therapy for bulimia nervosa: Statistical versus clinical significance of changes in symptoms across treatment
Authors: Openshaw Christine , Waller Glenn , Sperlinger David
Published: November 2004

Background

Cognitive‐behavior therapy (CBT) is the most effective treatment to date for bulimia nervosa. The current study investigated the effects of group CBT treatment (including some interpersonal elements) for bulimic clients.

Method

Twenty‐nine patients completed the Stirling Eating Disorder Scales, the Beck Depression Inventory, and the Beck Anxiety Inventory at assessment, pretreatment, end of treatment, and at 6 months follow‐up. Symptom change was explored in two ways. Statistically significant change was determined using repeated‐measures analyses of variance and clinically significant change was determined using criteria proposed by Jacobson & Truax (1991, Journal of Consulting and Clinical Psychology, 59, 12–19).

Results

There was an overall improvement in dimensional measures of bulimic and restrictive attitudes and behaviors (maintained at the 6‐month follow‐up), which was most closely matched by clinically significant changes in bulimic behaviors. Depression (but not anxiety) was also targeted effectively. Statistically significant improvements in psychological functioning were evident only for assertiveness, but the analysis of clinical significance showed improvement for some participants in self‐evaluation (self‐directed hostility).

Discussion

Group CBT (including interpersonal elements) is broadly effective when treating bulimia nervosa, but it does not work in all cases (and may lead to enhancement of restrictive characteristics in some cases). Tests of statistical and clinical significance provide different information, which can inform practice and aid in the development of treatments for patients who respond less well to current best practice. © 2004 by Wiley Periodicals, Inc. Int J Eat Disord 36: 363–375, 2004.
Purging behaviors and comorbidity as predictive factors of quality of life in anorexia nervosa
Authors: González‐Pinto Ana , Inmaculada Failde , Cristina Rodriguez , de Corres Blanca Fernández , Sonsoles Enjuto , Fernando Ramírez , Purificacion López
Published: November 2004

Objective

This study examined the predictive factors for the physical and mental summary components (PCS and MCS) of quality of life (SF‐36) in patients with anorexia nervosa.

Method

Forty‐seven patients with anorexia nervosa were studied. Assessment comprised psychiatric diagnosis by a clinical structured interview for Axis I disorders (SCID‐I) and personality disorders (SCID‐II), Clinical Global Impression (CGI), and Quality of Life (SF‐36).

Results

Anorexia nervosa, restrictive type, was diagnosed in 73.9% of the patients and 51% of the patients presented with comorbidity on Axis I or Axis II or both. The predictive variables for the PCS were poor outcome in previous year, comorbidity on Axes I and II, and female gender. The predictive variables for the MCS were the presence of comorbidity in one or the other of the Axis I or II disorders and purging behaviors.

Discussion

The current study suggests the importance of comorbidity and purging behaviors in the quality of life of these patients with anorexia nervosa. © 2004 by Wiley Periodicals, Inc. Int J Eat Disord 36: 445–450, 2004.
Dissonance thin‐ideal and didactic healthy behavior eating disorder prevention programs: Results from a controlled trial
Authors: Matusek Jill Anne , Wendt Sally J. , Wiseman Claire V.
Published: November 2004

Objective

Negative body image, a common problem among college‐age women in the United States, strongly correlates with low self‐esteem, disturbed eating behavior, and eating disorders. Psychoeducational programs have inconsistently shown improvement in body image, thin‐ideal internalization, eating behaviors, psychosocial functioning, and self‐esteem.

Method

In the current study, college women with body image concerns (N = 84) were randomly assigned to a cognitive dissonance‐based, thin‐ideal internalization, single‐session workshop (DTI; n = 26); a psychoeducational, healthy behavior, single‐session workshop (HB; n = 24); or a wait‐list control (WL; n = 34).

Results

Comparing baseline data with 4‐week follow‐up data, results indicated that both DTI and HB participants reported improvement in body image, thin‐ideal internalization, and eating behaviors.

Discussion

Results provide evidence that both interventions effectively reduce risk factors for eating pathology. © 2004 by Wiley Periodicals, Inc. Int J Eat Disord 36: 376–388, 2004.
Carbene Complexes of Nonmetals
Authors: Kirmse Wolfgang
Published: November 2004

Electrophilic carbenes accept a variety of n‐ and π‐donors. The products range from persistent ylides to matrix‐isolated xenon complexes. Ylides can be viewed as carbene complexes if they regenerate carbenesthermallyor undergoconcertedmethylene transfer reactions. According to these definitions, the present review focuses on oxonium and iodonium ylides. Transient π‐complexes appear to be involved in addition reactions of carbenes with arenes (but not with alkenes). Nucleophilic carbenes form adducts with Lewis acids which are, for the most part, stable and have been well characterized structurally. Only recently attention has been directed to reversible systems. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Total Synthesis and Olfactory Evaluation of 5β,10‐Dimethyl‐des‐A‐18‐nor‐androstan‐13β‐ol: A Potential Human Pheromone?
Authors: Kraft Philip , Popaj Kasim
Published: November 2004

5β,10‐Dimethyl‐des‐A‐18‐nor‐androstan‐13β‐ol (Limdrostanol, 11) was suspected to be the underlying parent steroid responsible for the interesting urinous‐animalic, woody olfactory properties of the commercial odorant Timberol® (6−9), and the captives Norlimbanol® (7) and Limbanol® (10), and so could constitute a potential human pheromone. We report the first synthesis of 11, starting with treatment of the bis‐Grignard reagent of 1,4‐dibromobutane (15) with γ‐butyrolactone (16), Appel−Lee bromination of the resulting diol 17 with elimination of the tertiary hydroxy group, and transformation of the obtained bromo alkene 18 into the corresponding triphenylphosphonium salt 13. This was subjected to a Schlosser−Wittig reaction with the γ,δ‐unsaturated aldehyde 14, prepared in turn by Grignard treatment of ethyl methacrylate (19) and subsequent Saucy−Marbet reaction of the resulting dimethyl carbinol 20 with ethyl vinyl ether (21). Cascade cyclization of the Schlosser−Wittig product 23 with methanesulfonic acid in dichloromethane at 0 °C afforded the tricyclic alkene 24, which was transformed into the target structure 11 by epoxidation with 3‐chloroperbenzoic acid and subsequent reduction with lithium triethylborohydride. In addition to 11, the corresponding 14α‐isomer 26 was obtained, and the olfactory properties of both are discussed. The high odor thresholds of 11 and 26, as well as the distinct differences in odor with 6−10, make it very unlikely that these des‐A‐18‐nor‐androstanols are the underlying odorous principle of 6−10, or that they function as human pheromones. An alternative synthesis of 11 by cyclization of 23 at 0 °C with 0.8 equivalents of methanesulfonic acid in formic acid as terminating nucleophile is also discussed, but gave only unsatisfactory yields. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Pulsed Amperometric Detection of Histamine at Glassy Carbon Electrodes Modified with Gold Nanoparticles
Authors: Carralero V. , González‐Cortés A. , Yáñez‐Sedeño P. , Pingarrón J. M.
Published: November 2004

Gold nanocrystal‐modified glassy carbon electrodes (nAu‐GCE) were prepared and used for the determination of histamine by flow injection and high performance liquid chromatography using pulsed amperometric detection (PAD) as the detection mode. Experimental variables involved in the electrodeposition process of gold from a HAuCl4 solution were optimized. A catalytic enhancement of the histamine voltammetric response was observed at the nAu‐GCE when compared with that obtained at a conventional Au disk electrode, as a consequence of the microdispersion of gold nanocrystals on the GC substrate. The morphological and electrochemical characteristics of the nAu‐GCE were evaluated by SEM and cyclic voltammetry. PAD using a very simple potential waveform consisting of an anodic potential (+700 mV for 500 ms) and a cathodic potential (−300 mV for 30 ms), was used to avoid the electrode surface fouling when histamine was detected under flowing conditions. Flow injection amperometric responses showed much higher Ip values and signal‐to‐noise ratios at the nAu‐GCE than at a conventional gold disk electrode. A limit of detection of 6×10−7 mol L−1 histamine was obtained. HPLC‐PAD at the nAu‐GCE was used for the determination of histamine in the presence of other biogenic amines and indole. Histamine was determined in sardine samples spiked at a 50 μg g−1 concentration level, with good results. Furthermore, the chromatographic PAD method was also used for monitoring the formation of histamine during the decomposition process of sardine samples.
Amperometric Sensors Based on Synthetic Hydrotalcites and Their Application for Ethanol Detection in Beer
Authors: Scavetta Erika , Tonelli Domenica
Published: November 2004

The electrochemical and electrocatalytic behavior of electrodes modified with a Co/Al‐NO3 hydrotalcite (HT) has been investigated and compared with that displayed by Ni/Al‐NO3 HT modified electrodes. Mono and polyhydric compounds have been tested to study electrocatalysis. At Co/Al‐NO3 HT modified electrodes only polyhydric compounds give e current signal, whereas at Ni/Al‐NO3 HT modified electrodes, both alcohols and polyhydric compounds can be detected. The different electrocatalytic behavior of Ni and Co based electrodes has been exploited to develop an analytic method for the selective determination of alcohols in the presence of polyhydric compounds. Samples of beer found on the Italian market have been analyzed to verify the validity of the proposed method in the detection of the ethanol content. The procedure does require neither a preliminar treatment nor a separation of the sample, but only the recording of two cyclic voltammogramms, one with the Co/Al‐NO3 and one with the Ni/Al‐NO3 HT modified electrode. The results obtained have been promising.
Characterization and Electrocatalytic Properties of Composite Poly(new fuchsin) and Phosphomolybdate Films
Authors: Chen Shen‐Ming , Fa Yu‐Hsiang
Published: November 2004

Organic/inorganic hybrid films of poly(new fuchsin) and phosphomolybdate (PMo12O$\rm{ {_{40}^{3-}}}$) have been prepared in acidic aqueous solutions. These new combination films are stable, electrochemically active, and can be produced on glassy carbon, platinum, gold, and transparent semiconductor tin oxide electrodes. An electrochemical quartz crystal microbalance along with cyclic voltammetry and UV‐visible absorption spectroscopy were used to study the in situ growth of the hybrid films. The hybrid poly(new fuchsin) and PMo12O$\rm{ {_{40}^{3-}}}$ films showed four obvious redox couples, and when transferred to various acidic aqueous solutions, the formal potentials of the four redox couples were found to be pH dependent. The electrocatalytic reduction of ClO$\rm{ {_{3}^{-}}}$, BrO$\rm{ {_{3}^{-}}}$, IO$\rm{ {_{3}^{-}}}$, SO$\rm{ {_{5}^{2{-}}}}$, S2O$\rm{ {_{8}^{{{2-}}}}}$, H2O2, and NO$\rm{ {_{2}^{-}}}$ by the hybrid poly(new fuchsin) and PMo12O$\rm{ {_{40}^{3-}}}$ films was achieved in acidic aqueous solutions. In an aqueous solution at pH 1.5, a hybrid poly(new fuchsin) and PMo12O$\rm{ {_{40}^{3-}}}$ film showed a higher electrocatalytic reduction activity of IO$\rm{ {_{3}^{-}}}$ than BrO$\rm{ {_{3}^{-}}}$ or ClO$\rm{ {_{3}^{-}}}$, and the order of electrocatalytic activity was IO$\rm{ {_{3}^{-}}}$>BrO$\rm{ {_{3}^{-}}}$>ClO$\rm{ {_{3}^{-}}}$. The order of electrocatalytic reduction of SO$\rm{ {_{5}^{{{2-}}}}}$, S2O$\rm{ {_{8}^{{{2-}}}}}$, H2O2, and NO$\rm{ {_{2}^{-}}}$ by hybrid poly(new fuchsin) and PMo12O$\rm{ {_{40}^{3-}}}$ films in an aqueous solution at pH 1.5 was NO$\rm{ {_{2}^{-}}}$>H2O2>S2O$\rm{ {_{8}^{{{2-}}}}}$ and SO$\rm{ {_{5}^{{{2-}}}}}$. The electrocatalytic reactions of the poly(new fuchsin) and PMo12O$\rm{ {_{40}^{3-}}}$ films were investigated using the rotating ring‐disk electrode method.
Carbon‐Nanotube Based Electrochemical Biosensors: A Review
Authors: Wang Joseph
Published: November 2004

This review addresses recent advances in carbon‐nanotubes (CNT) based electrochemical biosensors. The unique chemical and physical properties of CNT have paved the way to new and improved sensing devices, in general, and electrochemical biosensors, in particular. CNT‐based electrochemical transducers offer substantial improvements in the performance of amperometric enzyme electrodes, immunosensors and nucleic‐acid sensing devices. The greatly enhanced electrochemical reactivity of hydrogen peroxide and NADH at CNT‐modified electrodes makes these nanomaterials extremely attractive for numerous oxidase‐ and dehydrogenase‐based amperometric biosensors. Aligned CNT “forests” can act as molecular wires to allow efficient electron transfer between the underlying electrode and the redox centers of enzymes. Bioaffinity devices utilizing enzyme tags can greatly benefit from the enhanced response of the biocatalytic‐reaction product at the CNT transducer and from CNT amplification platforms carrying multiple tags. Common designs of CNT‐based biosensors are discussed, along with practical examples of such devices. The successful realization of CNT‐based biosensors requires proper control of their chemical and physical properties, as well as their functionalization and surface immobilization.
Multiwall Carbon Nanotube (MWCNT) Based Electrochemical Biosensors for Mediatorless Detection of Putrescine
Authors: Luong John H. T. , Hrapovic Sabahudin , Wang Dashan
Published: November 2004

γ‐Aminopropyltriethoxysilane (APTES)‐induced solubilization of multi‐wall carbon nanotube CNTs allowed for the modification of electrode surfaces. APTES also served as an immobilization matrix for putrescine oxidase (POx) to construct an amperometric biosensor. Although CNTs modified by APTES acted as semiconductors to reduce the exposed sensing surface, we reasoned that nanoscale “dendrites” of CNTS modified by APTES formed a network and projected outwards from the electrode surface and acted like bundled ultra‐microelectrodes that allowed access to the active site and facilitated direct electron transfer to the immobilized enzyme. Our biosensor was able to efficiently monitor direct electroactivity of POx at the electrode surface. The putrescine biosensor prepared using the modified glassy carbon electrode exhibited current response within 10 s with a detection limit of 500 nM.
Determination of Phenolic Compounds Based on the Tyrosinase‐ Single Walled Carbon Nanotubes Sensor
Authors: Zhao Qiang , Guan Lunhui , Gu Zhennan , Zhuang Qiankun
Published: November 2004

An amperometric sensor to phenolic compound was successfully constructed by immobilizing tyrosinase on the SWNTs modified glassy carbon (GC) electrode, which was covered with Nafion film. The sensitivity of the tyrosinase‐SWNTs sensor to phenol was 155 μA/mM. The tyrosinase‐SWNTs sensor also had good response to catechol, p‐chlorophenol and m‐cresol. Furthermore, benzoic acid could be detected based on the inhibition to tyrosinase activity.
Application of six‐phase soil heating technology for groundwater remediation
Authors: Smart Jimmy L.
Published: November 2004

A treatability study for implementation of a thermally enhanced environmental remediation technique has recently been completed at a Department of Energy uranium enrichment facility in Paducah, KY. The contaminated groundwater plume beneath the site, containing primarily trichloroethylene (TCE) and technetium‐99, is one of the largest‐ever documented plumes, encompassing some quarter of a billion m3 of contaminated water (10 billion gal). Various remediation technologies have been applied at the plant site over the past 15 years with moderate degrees of success. The presence of dense nonaqueous phase liquids (DNAPLs) in the groundwater are believed to be one of the major sources of TCE feeding the contaminated plume. Recovery/remediation of these DNAPLs was attempted in a small‐scale study with a soil‐heating technique called six‐phase soil heating. This technology uses buried resistive heating probes to heat the soil and associated liquids upward to 125° C to literally vaporize the TCE solvent. Vacuum recovery wells are used to direct solvent/water vapor flow to the surface for recovery. At the end of the test period, soil and groundwater samples were compared to baseline (pretreatment) samples. This comparison indicated an average TCE concentration reduction in soil of 98% and greater than 99% reduction in TCE concentrations in groundwater within the test cell. Two‐ and 4‐week posttreatment groundwater samples within the test cell have shown a slight fluctuating increase from end‐of‐test results, but all samples collected at various well depths indicate greater than 98% reduction in TCE concentration. Monitoring well data indicates six‐phase soil heating technology was effective in extracting solvent DNAPLs rather than merely relocating them. Results of this treatability study were judged to be favorable and a full‐scale implementation at the site has been recommended. © 2004 American Institute of Chemical Engineers Environ Prog, 2004
Delayed haematological complications of mustard gas
Authors: Ghanei Mostafa
Published: November 2004

Haematopoiesis could be affected by mustard gas. We randomly selected 318 chemical victims exposed to mustard gas and compared their cell blood counts and peripheral blood smears (PBS) with those of 377 healthy men, and also various haematological indices of 57 of these victims compared with previous data 5 years ago.

The average number of red blood cells and haemoglobin of victims compared with the controls was not signiﬁcantly different, but they were increased compared with data from 5 years ago. White blood cell counts, neutrophils and lymphocytes did not show any clinically meaningful difference compared with the control group but 20 cases with atypical lymphocytes in their PBS have been found.

Change in lymphocyte shape may be related to committed stem cell involvement. Further studies on bone marrow cells and cell markers are needed to document this hypothesis. The mild increase in erythroid cells and haemoglobin concentration may be due to chronic obstructive pulmonary disorder and other respiratory diseases in these patients. Copyright © 2004 John Wiley & Sons, Ltd.
Protection and inﬂammatory markers following exposure of guinea pigs to sarin vapour: comparative efﬁcacy of three oximes
Authors: Levy A. , Chapman S. , Cohen G. , Raveh L. , Rabinovitz I. , Manistersky E. , Kapon Y. , Allon N. , Gilat E.
Published: November 2004

The purpose of the present study was to compare the antidotal efﬁcacy and the combined effects on inﬂammatory markers of three oximes — toxogonine, TMB4 and 2‐PAM — in combination with anticholinergic drugs following exposure to sarin vapour by inhalation.

Guinea pigs restrained in plethysmographs were exposed to various doses of sarin vapour (in the range of 1.4–4.4ld50). The antidotal mixture was injected immediately (5–20 s) following exposure (3 mg kg−1 atropine and 1 mg kg−1 benactyzine in combination with 6 mg kg−1 toxogonine, 2 mg kg−1 TMB4 or 12 mg kg−1 2‐PAM). Bronchoalveolar lavage (BAL) samples were taken from surviving animals 24 h after exposure to determine the levels of inﬂammatory markers. A differential cell count was performed in BAL samples on Giemsa‐stained slides. The inﬂammatory markers — histamine and prostaglandins (PGE) — were measured in BAL using radioimmunoassay (RIA) techniques.

The survival rate in the various treatment groups and analysis of BAL samples showed that:

(i) Toxogonine, TMB4 and 2‐PAM, without pyridostigmine pretreatment, at doses that were proportional to their doses in the respective auto‐injectors, exhibited similar antidotal efﬁcacy against sarin exposure.

(ii) The results demonstrated that a centrally acting anticholinergic drug is essential in the antidotal mixture to ensure survival.

(iii) Histamine release and eosinophilia following sarin inhalation might require additional intervention, aimed at reducing the symptoms of allergic reaction and possibly expediting recovery. Copyright © 2004 John Wiley & Sons, Ltd.
Protective role of melatonin in ochratoxin a toxicity in rat heart and lung
Authors: Okutan Huseyin , Aydin Gulsen , Ozcelik Nurten
Published: November 2004

Ochratoxin A (OTA) is a mycotoxin produced by different fungi. The most pronounced adverse effect of OTA is hepatonephrotoxicity. Melatonin (MEL) has an antioxidant effect and has free‐radical scavenger properties. The effects of OTA on heart and lung tissue and possible ameliorating effects of MEL were investigated in rats. Twenty‐four rats were allocated to three groups (each with eight rats): control; OTA‐treated group (OTA dose 289 µg kg−1 per day); and OTA + MEL‐treated group (MEL dose 10 mg kg−1 per day). After 30 days of treatment, the histopathological changes in the heart and lung of all groups were examined. Compared with the control rats, myocardial tissue of rats treated with OTA showed extensive cytoplasmic vacuole formation, necrosis of the myocytes, dissolution of the nucleus, clumped ﬁbres, ﬁbrillolysis, swollen myocardial ﬁbres, small haemorrhagic areas and hyperaemic vessels (P < 0.05). In addition, lungs of rats treated with OTA showed alveolar congestion, alveolar cell hyperplasia, prominent alveolar septal vessels, variable intensity loss of alveolar architecture, intraparenchymal inﬂammatory inﬁltration, intraparenchymal hyperaemic vessels, respiratory epithelial proliferation, perivascular and peribronchial inﬂammation, pneumonic inﬁltration, distorted appearance of lung parenchyma and emphysematous areas (P < 0.05). In comparison with the OTA groups, the ameliorating effects of MEL in the lung damage parameters were on alveolar cell hyperplasia, prominent alveolar septal vessels, variable intensity loss of alveolar architecture, intraparenchymal inﬂammatory inﬁltration, perivascular inﬂammatory inﬂammation, distorted appearance of lung parenchyma and focal emphysematous areas in lung (P < 0.05). Melatonin also signiﬁcantly reduced myocardial damage in most of the parameters: extensive cytoplasmic vacuole formation, necrosis of the myocytes, clumped ﬁbres, ﬁbrillolysis, small haemorrhagic areas and hypaeremic vessels in heart (P < 0.05). On the other hand, MEL did not lower the degree of damage in lung and heart to the level of the control rats, except for the parameters of the interstitial oedema and small haemorrhagic areas only in myocardial tissue. Histopathological ﬁndings showed that OTA induced damage in heart and lung and MEL treatment signiﬁcantly reduced the degree of damage. Copyright © 2004 John Wiley & Sons, Ltd.
Study of caffeine in urine and saliva of horses subjected to urinary acidiﬁcation
Authors: Carregaro A. B. , Mataqueiro M. I. , Soares O. A. B. , Queiroz‐Neto A.
Published: November 2004

The study of caffeine in racing horses has been of growing concern in veterinary sports medicine since the Association of Racing Commissioners International (ARCI) stated that it has no valid therapeutic use in racehorses. We examined the kinetic alterations in the urinary excretion and salivary secretion of caffeine in seven horses subjected to urinary acidiﬁcation using ascorbic acid because this procedure can simulate the acidosis that follows anaerobic exercise. They participated in two treatment groups: the control group (SG) received 500 ml of saline and then 2.0 mg kg−1 caffeine i.v. 30 min later; and the acidiﬁed group (AG) was subjected to urinary acidiﬁcation with ascorbic acid at a dose of 0.5 g kg−1 i.v. and then 2.0 mg kg−1 caffeine i.v. 30 min later. Samples were collected 30 min before caffeine administration, immediately before caffeine administration (time zero) and at 0.25, 0.5, 1, 2, 4, 6, 8, 12, 24, 48 and 72 h afterwards. The samples were assayed by gas chromatography. The mean urinary pH for SG was 8.2, but for AG it was as low as 5.9 at 4 h, extending acidosis for up to 8 h. The kinetic curves for the two groups were similar for urinary excretion and salivary secretion. Differences occurred only in peak excretion and peak secretion in SG obtained at 1 h and 30 min, respectively, and in AG at 2 h and 1 h, respectively. This could be explained, in part, to the diuresis in AG compared with SG, resulting in less concentrated urine in the former group. The large difference between the pKa of caffeine and the pH of the medium may be responsible for the similar pharmacokinetics observed for the two groups. Copyright © 2004 John Wiley & Sons, Ltd.
Evaluation of the local irritation potential of hypertonic saline–dextran (HSD) in mice and rabbits
Authors: Dubick Michael A. , Wade Charles E.
Published: November 2004

Recent questions have renewed concerns regarding possible irritation associated with intravenous (i.v.) injection of 7.5% hypertonic saline (HS) or hypertonic saline–dextran (HSD: 7.5% NaCl and 6% Dextran‐70). This study investigated local injection site irritation associated with i.v., paravenous (p.v.), intramuscular (i.m.) and subcutaneous (s.c.) injection of HSD or its individual components. Mice (n = 10 per group per time point) and rabbits (n = 10 per group per time point) were infused i.v. with the maximum tolerated dose (28 or 20 ml kg−1, respectively) of HSD, HS, Dextran‐70 (D‐70) or lactated Ringer's solution (LR). Animals were observed at 1,2 and 4 h after injection and then twice daily until euthanized on day 3 or 14. In irritation studies, 24 rabbits were randomized to receive the four ﬂuids and they were evaluated histologically at 4, 24, 48 or 72 h after i.v., p.v., i.m. or s.c. infusion. The sites were observed immediately after injection, at 4 h and then twice daily until euthanasia. In surviving mice, bruising of the tail was observed in 6/18 and 5/19 animals in the HSD and HS groups, respectively, compared with 0/20 animals in the D‐70 or LR groups. Sloughing of the tail was eventually observed in two HSD‐infused and three HS‐infused mice, compared with none in the other groups. More bruises, hematomas and blebs were observed after i.v. or s.c. injection of HS and D‐70 than LR or HSD in the rabbit irritation studies, but the differences among groups were not statistically signiﬁcant. In the acute toxicity study in rabbits, bruising at the site of injection was observed in 7/20 and 5/14 surviving animals from the HSD and HS groups, respectively, but none was observed in the LR or D‐70 groups. These data suggest that, if infused over 5–10 min into a peripheral or central vein, a therapeutic dose of HSD (4 ml kg−1) should not induce any greater inﬂammation on the vein than LR. However, if signiﬁcant extravasation of hypertonic ﬂuid occurs, the possibility of localized, focal necrosis might be expected to occur. Copyright © 2004 John Wiley & Sons, Ltd.
Enzyme reactivator treatment in organophosphate exposure: clinical relevance of thiocholinesteratic activity of pralidoxime
Authors: Petroianu Georg A. , Missler Anke , Zuleger Katia , Thyes Caroline , Ewald Vanessa , Maleck Wolfgang H.
Published: November 2004

Organophosphate compounds are responsible for a large number of accidental and/or suicidal exposures and have been used also for warfare and terrorism. The mechanism of toxicity is by inhibition of cholinesterase. Oximes are the only enzyme reactivators clinically available but clinical experience with oximes is disappointing. There is a gap between laboratory data and clinical impression concerning the efﬁcacy of oxime compounds. Oximes are responsible for thiocholinesteratic activity, a spurious signal caused by interaction between pralidoxime and the thiocholine substrate used for photometric enzyme activity determinations. In a prospective, controlled, non‐randomized study performed in anaesthetized miniature pigs, we quantiﬁed the extent of pralidoxime‐induced cholinesteratic pseudo‐activity ex vivo (human blood) and in vivo (minipig) in order to be able to correct values obtained by photometric methods. Plasma cholinesteratic activity using two substrates (acetylthiocholine and butyrylthiocholine) was determined in vitro and in vivo in the presence of pralidoxime.

Pralidoxime reacts with the substrate (acetyl‐ and butyrylthiocholine) used for enzyme activity determinations, producing a spurious signal implying cholinesterase activity (even in the absence of plasma and thus of any enzyme). Cholinesterase activities determined photometrically after pralidoxime therapy can be erroneously high. Although in theory this could mislead clinicians into assuming an efﬁcacious therapy, this is unlikely to occur in vivo under normal pralidoxime dosing conditions. To avoid any ambiguity it is recommended that blood be drawn for enzyme activity determinations prior to reactivator use and no less than 1 h after its administration. Copyright © 2004 John Wiley & Sons, Ltd.