bluuebunny/crossref_metadata_2025 huggingface dataset:
The biodegradation mechanism of calcium phosphate biomaterials in bone
Authors: Lu Jianxi , Descamps Michel , Dejou Jacques , Koubi Gilles , Hardouin Pierre , Lemaitre Jacques , Proust Jean‐Pierre
Published: September 2002

This study was undertaken to understand the biodegradation mechanisms of calcium phosphate (Ca‐P) biomaterials with different crystallization. Two types of sintered Ca‐P porous ceramic (HA and β‐TCP) and a Ca‐P bone cement (CPC) were implanted into cavities drilled in rabbit femoral and tibiae condyles. The results have shown that a material biodegradation was rapid in the β‐TCP and the CPC, but very weak in the HA. This biodegradation presented a decrease of material volume from the periphery to the center as well as a particle formation causing phagocytosis by numerous macrophages and multinucleated giant cells in the CPC. In the β‐TCP, there was a peripheral and central decrease of material volume as well as an absence of particle formation or visible phagocytosis. The process of biodegradation is considered to be directly influenced by the type of material crystallization. The sintered bioceramics processed at a high temperature exhibit good crystallization and are primarily degraded by a process dependent on interstitial liquids. However, the bone cement is formed by physicochemical crystallization and is degraded through a dissolution process associated with a cellular process. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res (Appl Biomater) 63: 408–412, 2002
A Symmetry adapted tessellation of the GEPOL surface: applications to molecular properties in solution
Authors: Pomelli Christian Silvio , Tomasi Jacopo , Cammi Roberto
Published: September 2002

A procedure to partition the GEPOL molecular surface into tesserae that respects the molecular symmetry constraints is presented. Using this method it is possible to build a solvent reaction field for the Polarizable Continuum Model with the same symmetry of the nuclear potential. Several applications are reported and discussed to evaluate the performance of this new procedure. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 1262–1272, 2001
MD‐based CD calculations for the assignment of the absolute axial configuration of the naphthylisoquinoline alkaloid dioncophylline A
Authors: Bringmann Gerhard , Mühlbacher Jörg , Repges Charlotte , Fleischhauer Jörg
Published: September 2002

The circular dichroism (CD) of the biaryl alkaloid dioncophylline A (2) was investigated by CD calculations; the structures were generated by molecular dynamics (MD) simulations using the force field CVFF. From these structures the CD spectra were calculated with the semiempirical method CNDO/2S. Summing up the single CD spectra yielded the final spectrum. In contrast to our earlier method based on the Boltzmann weighting, the MD‐assisted approach permitted to assign the flexible biaryl axis of dioncophylline A (2), which is found to be P. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 1273–1278, 2001
First‐principles conformational analysis of the C36H36 spheriphane, a prototype hydrocarbon host cage
Authors: Cioslowski Jerzy , Szarecka Agnieszka
Published: September 2002

Comprehensive B3LYP/6‐311G** electronic structure calculations establish that, unlike closely related species such as cyclophanes, the C36H36 spheriphane (heptacyclo[13.13.21,15.28,22.13,27.16,10.113,17.120,24] hexatriaconta‐1,3(33),6,8,10(34),13,15,17(35),20,22,24(36),27‐dodecaene) possesses only seven energetically distinct conformers, out of which five exist in enantiomeric pairs and two are achiral. These local energy minima are interrelated through an intricate net of 20 reaction paths involving single inversions at the CH2 CH2bridges. In particular, the T and C3 conformers, which are predicted to coexist in comparable concentrations at ambient temperatures, are linked through three consecutive single‐bridge inversions that proceed through the overall barrier of only 5.3 (kcal/mol). This barrier is compatible with coalescence temperatures well below those employed in the recently measured 1H and 13C NMR spectra, explaining the observed lack of line splittings. Both the T→C3 pathway and the racemizations of the low‐energy conformers involve C1 and C2 intermediates that are expected to be present in detectable amounts. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 1279–1286, 2001
Decorin transfection in human mesangial cells downregulates genes playing a role in the progression of fibrosis
Authors: Costacurta Antonia , Priante Giovanna , D'Angelo Angela , Chieco‐Bianchi Luigi , Cantaro Salvatore
Published: September 2002

The proteoglycan decorin inhibits TGF‐β; therefore, it could antagonize progression of fibrotic diseases associated with activation of TGF‐β1. The effect of decorin transfection in human mesangial cells (HMCs) on the expression of genes related to kidney fibrosis was investigated. HMCs, isolated from glomeruli of healthy portions of human kidneys removed due to carcinoma, were histochemically typed. Decorin cDNA cloned in a eukaryotic expression vector was transfected into HMCs. Gene expression of fibrogenetic cytokines and fibrotic proteins TGF‐β1, PDGF‐β, α1 collagen type IV, α1 collagen type I, fibronectin, and tenascin was analyzed, by reverse transcription polymerase chain reaction (RT‐PCR), 24 hr after transfection. Immunoblotting analysis of protein extracts using anti‐decorin IgG, revealed a positive signal of about 52 MDa, corresponding to the molecular weight of decorin, in cultures transfected with the decorin gene. Decorin mRNA increased about 12 times in cultures transfected with the construct pCR3.1‐Deco. Cells with increased decorin synthesis showed a 61% decrease of TGF‐β1 mRNA, a 71% reduction of α1 collagen type IV mRNA, and a 29% reduction of fibronectin mRNA. This study is the first to investigate decorin transfection into human mesangial cells, and supports the use of the decorin gene to control the progression of glomerular and interstitial fibrosis in kidney diseases. © 2002 Wiley‐Liss, Inc.
Bidirectional (positive/negative) interference of spironolactone, canrenone, and potassium canrenoate on serum digoxin measurement: elimination of interference by measuring free digoxin or using a chemiluminescent assay for digoxin
Authors: Dasgupta Amitava , Saffer Helene , Wells Alice , Datta Pradip
Published: September 2002

Spironolactone and potassium canrenoate (aldosterone antagonist diuretics) are often used with digoxin in clinical practice. Spironolactone, potassium canrenoate, and their common metabolite canrenone cross‐react with the fluorescence polarization immunoassay (FPIA) for digoxin, and can falsely elevate serum digoxin concentrations. Serum digoxin concentrations were falsely lowered when the microparticle enzyme immunoassay (MEIA) was used. Aliquots of drug‐free serum were supplemented with therapeutic and above‐therapeutic concentrations of spironolactone, canrenone, and potassium canrenoate, and apparent digoxin activities were measured. We observed digoxin‐like activities in the FPIA, but observed no activity with the MEIA or the chemiluminescent assay (CLIA). However, when serum digoxin pools prepared from patients receiving digoxin were supplemented with these compounds, we observed suppression of total digoxin levels with the MEIA. In contrast, no interference was observed in the presence of these compounds when CLIA was used for digoxin measurement. These compounds are strongly protein‐bound, and no apparent digoxin activity was observed in the protein‐free ultrafiltrate when drug‐free sera were spiked with high levels of these compounds. Taking advantage of strong protein binding of these compounds and weak protein binding of digoxin (25%), interference of spironolactone, canrenone, and potassium canrenoate in FPIA and MEIA digoxin assays can be mostly eliminated by monitoring free digoxin concentration. Another approach to avoid this interference is to use the CLIA digoxin assay. © 2002 Wiley‐Liss, Inc.
Human immunodeficiency virus genotype and hypertriglyceridemia
Authors: Anderson Soni J. , Bradley John F. , Ferreira‐Gonzalez Andrea , Garrett Carleton T.
Published: September 2002

Many HIV patients develop a progressive syndrome of abnormal body fat distribution accompanied by hypertriglyceridemia. Antiretroviral agents are thought to be etiologic in the syndrome, often termed “highly active antiretroviral therapy (HAART)‐associated lipodystrophy.” In the course of clinical HIV genotype testing, we observed that our HIV patients with hypertriglyceridemia had viral genotypes that were more highly mutated than those of our therapy‐matched control patients. Hypertriglyceridemia was statistically associated with predicted resistance for three nucleoside reverse transcriptase inhibitors: zidovudine, abacavir, and stavudine. Statistical analysis of 51 patients in retrospect revealed a strong association of mutations at reverse transcriptase codons M41 and T215 with hypertriglyceridemia (chi‐square (χ2) = 8.375, P=.0038; and χ2=7.445, P=.0064, respectively). This was in contrast to silent mutations, which occurred at equivalent rates in retroviral genotypes of patients with and without hypertriglyceridemia. The findings imply that the HIV genotype itself may be a significant etiologic factor in antiretroviral‐associated lipodystrophy. © 2002 Wiley‐Liss, Inc.
Semiquantitative analysis of urinary low protein levels using silver dot blot assay
Authors: Matsuda Kazuyuki , Hiratsuka Nobuo , Kurihara Yuriko , Shiba Kiyoko
Published: September 2002

We designed a semiquantitative analysis of urinary low protein levels using silver dot blot assay. In this method, 3 μl of urine are blotted to one dot onto a cellulose acetate membrane, which is stained by a colloidal silver staining reagent, and the optical density of the silver stained urinary protein is measured at 500 nm using a densitometer. There was a good linearity between 2.5 mg/L and 100 mg/L and a gentle linearity between 100 mg/L and 200 mg/L, and the minimum sensitivity was 2.5 mg/L. This method is suitable for semiquantitative analysis of urinary protein levels less than 300 mg/L, which can not be determined precisely by dipstick. J. Clin. Lab. Anal. 15:171–174, 2001. © 2001 Wiley‐Liss, Inc.
Electrophoretic analysis of urinary proteins in diabetic adolescents
Authors: Koliakos George , Papachristou Fotis , Papadopoulou Maria , Trachana Varvara , Gaitatzi Mary , Sotiriou Ioannis
Published: September 2002

Pathological changes in the urine sodium dodecyl sulphate gel electrophoresis (SDS PAGE) patterns often precede the occurrence of any sign of renal involvement in diabetes. However, data concerning the most frequent SDS PAGE pattern of the urine in early stages of type I diabetes mellitus are controversial. In the present study an SDS PAGE technique has been used that provides an adequate sensitivity for the detection of the abnormal pattern. Urinary proteins have been analyzed by SDS PAGE in twenty two diabetic adolescents and twenty four age matched controls. Albumin concentration, and N acetyl‐beta‐D‐glucosaminidase (NAG) activity were also measured in the same samples. There was no significant difference in urine albumin concentration and NAG activity between diabetic children and controls. However twelve patients showed an electrophoretic pattern characteristic for glomerulopathy, two had a pattern indicating tubular dysfunction and another two patients had a mixed pattern. Among the twenty four controls only three showed abnormal electrophoretic patterns. The results support the view that early stages of diabetic nephropathy may involve both glomerular and tubular dysfunction. However the exact clinical and prognostic significance of the information provided by SDS PAGE analysis remains to be elucidated. J. Clin. Lab. Anal. 15:178–183, 2001. © 2001 Wiley‐Liss, Inc.
Quantitation of TGF‐β1 mRNA in porcine mesangial cells by comparative kinetic RT/PCR: Comparison with ribonuclease protection assay and in situ hybridization
Authors: Ceol Monica , Forino Monica , Gambaro Giovanni , Sauer Ulrich , Schleicher Erwin D. , D’Angelo Angela , Anglani Franca
Published: September 2002

Gene expression can be examined with different techniques including ribonuclease protection assay (RPA), in situ hybridisation (ISH), and quantitative reverse transcription–polymerase chain reaction (RT/PCR). These methods differ considerably in their sensitivity and precision in detecting and quantifying low abundance mRNA. Although there is evidence that RT/PCR can be performed in a quantitative manner, the quantitative capacity of this method is generally underestimated. To demonstrate that the comparative kinetic RT/PCR strategy—which uses a housekeeping gene as internal standard—is a quantitative method to detect significant differences in mRNA levels between different samples, the inhibitory effect of heparin on phorbol 12‐myristate 13‐acetate (PMA)‐induced‐TGF‐β1 mRNA expression was evaluated by RT/PCR and RPA, the standard method of mRNA quantification, and the results were compared. The reproducibility of RT/PCR amplification was calculated by comparing the quantity of G3PDH and TGF‐β1 PCR products, generated during the exponential phases, estimated from two different RT/PCR (G3PDH, r = 0.968, P = 0.0000; TGF‐β1, r = 0.966, P = 0.0000). The quantitative capacity of comparative kinetic RT/PCR was demonstrated by comparing the results obtained from RPA and RT/PCR using linear regression analysis. Starting from the same RNA extraction, but using only 1% of the RNA for the RT/PCR compared to RPA, significant correlation was observed (r = 0.984, P = 0.0004). Moreover the morphometric analysis of ISH signal was applied for the semi‐quantitative evaluation of the expression and localisation of TGF‐β1 mRNA in the entire cell population. Our results demonstrate the close similarity of the RT/PCR and RPA methods in giving quantitative information on mRNA expression and indicate the possibility to adopt the comparative kinetic RT/PCR as reliable quantitative method of mRNA analysis. J. Clin. Lab. Anal. 15:215–222, 2001. © 2001 Wiley‐Liss, Inc.
Trauma focus group therapy for combat‐related PTSD: An update
Authors: Foy David W. , Ruzek Josef I. , Glynn Shirley M. , Riney Sherry J. , Gusman Fred D.
Published: September 2002

Individual cognitive–behavioral therapy involving directed exposure to memories of traumatic events has been found to be effective in treating posttraumatic stress disorder. In this article, we present updated information on an alternative group form of exposure therapy: manualized trauma‐focus group therapy (TFGT), designed as an efficient means of conducting directed exposure. We describe the cognitive–behavioral and developmental models from which the approach was derived, present an overview of session topics and a case illustration, provide guidelines for referring individuals to TFGT, and offer suggestions for future research. © 2002 Wiley Periodicals, Inc. J Clin Psychol/In Session 58: 907–918, 2002.
Health education groups for caregivers in an HMO
Authors: Toseland Ronald W. , McCallion Philip , Smith Tamara , Huck Steve , Bourgeois Pauline , Garstka Teri A.
Published: September 2002

The short‐term effectiveness of a Health Education Group (HEP) intervention program for spouses of frail older adults was compared to the usual care (UC) offered to the spouses of frail older persons in a staff model health maintenance organization. HEP is a multicomponent group program offered in eight weekly, two‐hour group sessions, and ten monthly, two‐hour follow‐up group sessions. It includes emotion‐focused and problem‐focused coping strategies, education, and support. One‐hundred and five spouses were recruited and randomly assigned to HEP (n = 58) or UC (n = 47). Spouse caregivers and care recipients were assessed within two weeks of intervention and within two weeks after the completion of the eight weekly group meetings. The results indicate that, for caregivers, HEP was more effective than UC in reducing depression, maintaining social integration, increasing effectiveness in solving pressing problems, increasing knowledge of community services and how to access them, changing caregivers' feelings of competence, and the way they respond to the care giving situation. No significant differences, however, were found between care recipients in the two arms of the study on any of the outcome measures. © 2001 John Wiley & Sons, Inc. J Clin Psychol 57: 551–570, 2001
Plaud on Ilardi and Feldman
Authors: Plaud Joseph J.
Published: September 2002

A cultural analysis is given to the premise that clinical psychology is a discipline of theoretical fragmentation. It is argued that the discipline will achieve paradigmatic status as an applied science by reestablishing the link between behavioral theory and clinical applications. © 2001 John Wiley & Sons, Inc. J Clin Psychol 57: 1109–1111, 2001.
A tale of three blind men on the proper subject matter of clinical science and practice: Commentary on Plaud's behaviorism vs. Ilardi and Feldman's cognitive neuroscience
Authors: Forsyth John P. , Kelly Megan M.
Published: September 2002

Plaud (J Clin Psychol 57, 1089–1102, 1109–1111, 1119–1120) and Ilardi and Feldman (J Clin Psychol 57, 1067–1088, 1103–1107, 1113–1117, 1121–1124) argue for two very different approaches to clinical science and practice (i.e., behavior analysis and cognitive neuroscience, respectively). We comment on the assets and liabilities of both perspectives as presented and attempt to achieve some semblance of balance between the three protagonists embroiled in this current debate. The vision of clinical science we articulate is more ecumenical and evolutionary, rather than paradigmatic and revolutionary. As we see it, the problem clinical psychology faces is much larger than the authors let on; namely, how best to make clinical science meaningful and relevant to practitioners, consumers, the general public, and the behavioral health‐care community. Clinical psychology's immediate internal problem is not pluralism with regard to subject matter, worldview, methodology, or school of thought, but pluralism in clinical psychologists' adherence to a scientific epistemology as the only legitimate form of clinical psychology. On this latter point, we still have a very long way to go. © 2001 John Wiley & Sons, Inc. J Clin Psychol 57: 1133–1148, 2001.
In situ generation of hydrogen peroxide and its use for enzymatic degradation of 2,4,6‐trinitrotoluene
Authors: Lee Ki Beom , Gu Man Bock , Moon Seung‐Hyeon
Published: September 2002

A novel electroenzymatic method hybridizing both electrochemical and enzymatic reactions and using lignin peroxidase (Lip) for treatment of TNT (2,4,6‐trinitrotoluene) waste was studied. In the presence of Phanerochaete chrysosporium lignin peroxidase, TNT was degraded in an electrochemical reactor using hydrogen peroxide, produced by an electrode reaction. The effectiveness of the electroenzymatic method was examined in this study. The efficiency of removal of TNT was greater than that of biochemical methods under optimal conditions. The effects of reaction conditions on TNT degradation and denitrification, TOC removal efficiency, and power consumption were also investigated. A potential (vs Ag/AgCl) of +0.1 V was selected as being optimal for the electroenzymatic reaction. TNT degradation was significantly improved in the combined veratryl alcohol–lignin peroxidase oxidation procedure, showing complementary effects of veratryl alcohol (VA) in the TNT degradation reaction. Denitrification was found to be proportional to the amount of TNT degraded. One intermediate, 2,4‐diamino‐6‐nitrotoluene, derived from the oxidative degradation of TNT, was eluted on an HPLC chromatogram and was detected using mass spectrometry. The electroenzymatic method had a lower power requirement than electrochemical oxidation at −0.2 and −0.4 V. The electroenzymatic method may be easily applied to biodegradation systems and provide added benefit for highly recalcitrant chemicals since the system would not be susceptible to the toxicity of the chemical. Also H2O2 instability and decomposition in the samples after preparation would not be of concern.

© 2001 Society of Chemical Industry
Removal of pentane and styrene mixtures from waste gases by a trickle‐bed air biofilter
Authors: Lu Chungsying , Lin Min‐Ray , Wey Innho
Published: September 2002

The biofilter process is a relatively new technology that has been proven to be more cost‐effective than traditional technologies for treating many kinds of volatile organic compounds (VOCs) from waste gases. Pentane and styrene mixtures are commonly encountered in the manufacture of polymers such as polystyrene. This research attempts to employ a trickle‐bed air biofilter (TBAB) for treating such mixtures under different influent carbon loadings. In the pseudo‐steady‐state conditions, the elimination capacities of pentane and styrene increased but the removal efficiencies decreased with increased influent carbon loading. The removal efficiencies of styrene were higher than those of pentane, indicating that styrene is a preferred substrate and the differences were enhanced at a high carbon loading. Removal efficiencies of more than 80% were achieved with influent carbon loadings of pentane and styrene below 25 and 68 gm−3 h−1, respectively. The TBAB appears to be efficient for controlling VOC emissions with low pentane and medium styrene loadings, and the effectiveness could be maintained over 140 days of laboratory operation.

© 2001 Society of Chemical Industry
Remediation of acidic waste waters using immobilised, acidophilic sulfate‐reducing bacteria
Authors: Kolmert Åsa , Johnson D Barrie
Published: September 2002

Acidic waste waters from industrial and mining activities constitute a wordwide environmental hazard. ‘Acid mine drainage’ (AMD) waters are often highly acidic (pH < 4), contain elevated concentrations of sulfate and dissolved metals, and are toxic to most life forms. Whilst bioremediation of acidic, metal‐contaminated waters using sulfate‐reducing bacteria (SRB) has been successfully demonstrated in pilot‐scale and full‐scale operations during the past decade, the sensitivity of characterised SRB to acidity limits their use in AMD remediation. In the current study, we have evaluated the potential use of novel acidophilic SRB for remediating acidic waste waters, in comparision with, and in conjuction with, neutrophilic SRB. Three SRB‐populations (a mixed population of acidophilic isolates, a neutrophilic culture and a mixed acidophilic/neutrophilic consortium) were immobilised on porous glass beads, packed into perspex columns and the three bioreactors percolated with synthetic medium for several months. Energy and carbon source utilisation, and tolerance to acid stress of the different consortia were evaluated. Acidophilic SRB were more efficient than the neutrophilic culture in coupling ethanol oxidation to sulfate reduction and all of the substrates tested were oxidised to acetic acid. The bioreactors containing acidophilic SRB reduced sulfate and generated alkalinity when challenged with influent at pH 3 and above, indicating that such bacteria have potential for bioremediating highly acidic waste waters. Average conversion rates of 0.25–0.30 g SO42− reduced dm−3 day−1 were achieved with bioreactors containing acidophilic SRB, percolated with a pH 4 liquid medium.

© 2001 Society of Chemical Industry
Catalytic synthesis of toluene‐2,4‐diisocyanate from dimethyl carbonate
Authors: Wang Yanji , Zhao Xinqiang , Li Fang , Wang Shufang , Zhang Jiyan
Published: September 2002

The process for catalytic synthesis of toluene‐2,4‐diisocyanate (TDI) from dimethyl carbonate (DMC) consists of two steps. Starting from the catalytic reaction between toluene‐2,4‐diamine (TDA) and DMC, dimethyl toluene‐2,4‐dicarbamate (TDC) is formed, and then decomposed to TDI. For the first step, the yield of TDC is 53.5% at a temperature of 250 °C, over Zn(OAc)2/α–Al2O3 catalyst. For the second step, the yield of TDI is 92.6% at temperatures of 250–270 °C and under pressure of 2.7 kPa, over uranyl zinc acetate catalyst, when di‐n‐octyl sebacate(DOS) is used as heat‐carrier, and a mixture of tetrahydrofuran (THF) and nitrobenzene is used as solvent.

© 2001 Society of Chemical Industry
The physico‐chemical characteristics of thermophilic aerobic sludges
Authors: Riley David W , Forster Christopher F
Published: September 2002

An examination of the rheological properties of two aerobically digested sludges, one from an autothermal thermophilic digester (ATAD), the other from a thermophilic digester (TAD), showed that both sludges exhibited yield stresses which were an order of magnitude lower than activated sludges at similar solids' concentrations. However, their filtration characteristics, as measured by the capillary suction time method, were appreciably poorer than those of thickened activated sludge. Particle size analysis and microscopic examinations showed that both the thermophilic sludges contained a predominance of very small particles which would cause blinding of the filters. The surface charge carried by the thermophilic sludges was lower than that associated with activated sludge samples. These results are comparable with earlier work which showed that rheological properties were associated with surface charge. However, the bound water content of the thermophilic sludges did not appear to be associated with the yield stress. Live/dead staining showed that in both samples there were free‐swimming viable bacteria.

© 2001 Society of Chemical Industry
Increased activity of Chromobacterium viscosum lipase in AOT reverse micelles in the presence of short chain methoxypolyethylene glycol
Authors: Hayashi Y , Talukder M M R , Wu Jinchuan , Takeyama T , Kawanishi T , Simizu N
Published: September 2002

The activity of Chromobacterium viscosum lipase (glycerol‐ester hydrolase, EC 3.1.1.3) entrapped in AOT/isooctane and AOT/Tween 85/isooctane reverse micelles was significantly increased by the addition of short chain methoxypolyethylene glycols (MPEGs), taking the hydrolysis of olive oil as a model reaction. The molecular weight of MPEG had a strong effect on the lipase activity, and MPEG of nominal molecular weight 550 was found to be the most effective. To optimize the factors affecting enzymatic hydrolysis of olive oil in reverse micellar systems containing MPEG 550, the effect of various parameters, such as Wo (molar ratio of water to surfactant), pH, ionic strength, surfactant concentration and temperature were investigated. A kinetic model considering the substrate adsorption equilibrium between the bulk phase of organic solvent and the micellar phase was also successfully used to understand the enzyme activity in the presence of MPEG 550. Both the Michaelis constant and the substrate adsorption equilibrium constant were obviously reduced as compared with those obtained in the simple AOT reverse micellar system.

© 2001 Society of Chemical Industry
Enhanced ethanol production from enzymatically treated steam‐exploded rice straw using extractive fermentation
Authors: Nakamura Yoshitoshi , Sawada Tatsuro , Inoue Eiichi
Published: September 2002

Alcohol fermentation of an enzymatic hydrolyzate of exploded rice straw was studied experimentally. Rice straw was treated under variable conditions, such as steam pressure and steaming time. The exploded rice straw was separated into water‐soluble material, methanol‐soluble lignin, Klason lignin, and a mixture of cellulose and a low molecular weight substance. The effects of steam explosion on the characteristics of the exploded rice straw were clarified from the point of view of the amounts of extractive components. Steam explosion was found to be effective for the delignification of rice straw and for increasing its susceptibility to enzyme hydrolysis and alcohol fermentation. The polysaccharides (cellulose and hemicellulose) in the rice straw treated at a steam pressure of 3.5 MPa with a steaming time of 2 min were hydrolyzed almost completely into monosaccharides, (ie glucose and xylose) by a mixture of Trichoderma viride cellulase (Meicelase) and Aspergillus aculeatus cellulase (Acucelase). The enzymatic hydrolyzate of exploded rice straw was converted into ethanol efficiently by Pichia stipitis and the ethanol yield from sugar was about 86%(w/w) of the theoretical value. The ethanol concentration in a membrane bioreactor coupled with a pervaporation system reached 50 gdm−3 and was about five times higher than that in the culture broth. The energy efficiency (ratio of combustion energy of ethanol produced to energy for steam explosion) reached a maximum value at a pressure of 3.5 MPa for 2 min.

© 2001 Society of Chemical Industry
Purification of combustion fly ashes using the SERVO process
Authors: Allimann‐Lecourt C , Bailey T H , Cox M
Published: September 2002

The SERVO process involves the extraction of heavy metals using a volatile chelating extraction reagent that is selective for chosen contaminating metals. The extractant is heated and the vapour passed through a heated bed of fly ash where reaction occurs with the contaminant metals to produce volatile metal–reagent complexes at relatively low temperatures and normal pressure. These can be condensed from the vapour phase or, in suitable circumstances, reduced to the element and the reagent recycled. Previous studies demonstrated the extraction of nickel from low‐grade laterite ores using β‐diketones and Schiff bases. Current research is now directed towards the selective extraction of metals such as zinc, lead, cadmium, molybdenum and vanadium from combustion ashes. New extractants and their metal complexes have been synthesised to determine their thermal stability and volatility. Of those prepared, complexes of tetra‐iso‐propyldithiophosphoramide are the most thermally stable. Using thermogravimetric analysis the kinetics of the process have been studied to optimise the operating conditions. The SERVO process has been used on a laboratory scale to study the extraction of metals from coal combustion fly ash, waste incinerator fly ash and Orimulsion ash. Extraction has been found to depend on metal speciation and the paper presents results of the metal removal with three different extractants correlated with the speciation of the metals in the feed.

© 2002 Society of Chemical Industry
Sugar‐cane bagasse ash (SCBA): studies on its properties for reusing in concrete production
Authors: Payá J , Monzó J , Borrachero M V , Díaz‐Pinzón L , Ordóñez L M
Published: September 2002

Sugar cane bagasse is an industrial waste which is used worldwide as fuel in the same sugar‐cane industry. The combustion yields ashes containing high amounts of unburned matter, silicon and aluminium oxides as main components. These sugar‐cane bagasse ashes (SCBA) have been chemically, physically and mineralogically characterized, in order to evaluate the possibility of their use as a cement‐replacing material in the concrete industry. Determination of parameters such as carbon content (by thermal analysis methods), presence of crystalline material (by X‐ray diffractometry), granulometric distribution (by laser diffraction in water suspensions), morphology of particles (by scanning electron microscopy) and reactivity towards lime (pozzolanic activity by thermogravimetric monitoring in lime/SCBA and cement/SCBA pastes) have been carried out.

© 2002 Society of Chemical Industry
Advantages in the use of fly ashes in cements containing pozzolanic combustion residues: silica fume, sewage sludge ash, spent fluidized bed catalyst and rice husk ash
Authors: Payá J , Monzó J , Borrachero M V , Amahjour F , Girbés I , Velázquez S , Ordóñez L M
Published: September 2002

The enhancement in the workability of Portland cement concrete when coal fly ashes are added to the mix is well‐known. This behaviour has been attributed to the spherical shape and the smooth surface of the fly ash particles. On the other hand, when other combustion residues with pozzolanic properties are added to concrete mix formulations, a loss in workability is observed, and an increase in water content may be necessary for obtaining a satisfactory plastic consistency of the concrete, or alternatively chemical additives may be used (plasticizers and superplasticizers). The effect of the combination of fly ash with other mineral admixtures in respect of the effect on the workability of mortars has been studied. The pozzolanic combustion residues examined were: silica fume, sewage sludge ash, spent fluid catalytic cracking catalyst and rice husk ash. Additionally, and due to the pozzolanic properties of coal fly ash and these residues, the strength developments of Portland cement mortars containing fly ash and the selected admixtures have also been measured.

© 2002 Society of Chemical Industry
Development of new fire‐proof products made from coal fly ash: the CEFYR project
Authors: Vilches Luis F , Fernández‐Pereira Constantino , Olivares del Valle Joaquín , Rodríguez‐Piñero Miguel , Vale José
Published: September 2002

Fly ash (FA) is a by‐product of coal combustion in power plants whose characteristics depend on the type of combustion process and coal properties. A large proportion of FA is used by the cement and concrete industries, but most is disposed to landfill, potentially causing environmental problems. The main objective of the CEFYR project was to study new fire‐proof products (FPP) in the laboratory and at the pilot level, employing FA from a pulverized coal combustion power station and other industrial wastes and cellulosic derivatives. As a result of the project, new FPP have been developed and manufactured as panels or as sprayed surfaces. In this paper is described one such product: panels formed by simple compaction or by vacuum filtration using coal fly ash, waste paper and other industrial wastes. After thermal treatment to eliminate the cellulosic matrix and produce high porosity products, their stability at high temperatures was assessed. The results show that the developed FPP are stable and have acceptable physical and mechanical properties. In addition, the insulating capacity of the products was assessed by submitting one of the panel faces to heat according to standard fire resistance tests, and measuring the temperature rise on the cold face. The results indicate that some of the manufactured FPP have better insulating properties than other commercial fire‐resistant products, and consequently, that it is possible to produce FPP using FA and other residues as raw materials, using simple, cost‐effective processing methods.

© 2002 Society of Chemical Industry
Production of delta‐endotoxin by Bacillus thuringiensis subsp kurstaki and overcoming of catabolite repression by using highly concentrated gruel and fish meal media in 2‐ and 20‐dm3 fermenters
Authors: Zouari Nabil , Achour Omar , Jaoua Samir
Published: September 2002

Delta‐endotoxin production by a strain of Bacillus thuringiensis subsp kurstaki exhibiting larvicidal toxicity towards lepidoptera was investigated in 2‐ and 20‐dm3 fermenters, using gruel‐ and fish meal‐based media. The results show clearly that in such complex media, aeration plays an important role in bioinsecticide production. Optimal aeration led to improvement of delta‐endotoxin concentrations with decreases of final spore count and proteolytic activity. Moreover, in order to use high gruel concentrations, a fermenter configuration with an efficient aeration system should be used. In a 20‐dm3 Biolafite fermenter, 59 g dm−3 or 75 g dm−3 gruel was used to produce bioinsecticides with a significant reduction of carbon catabolite repression of delta‐endotoxin synthesis. This result is very interesting in order to produce high final delta‐endotoxin concentrations in the culture broth. It was also concluded, by considering the key role of oxidative pathways in delta‐endotoxin synthesis, that oxygen supply must be adequate for bioinsecticide production at high substrate concentrations. Moreover, the role of sodium chloride in improving delta‐endotoxin production is dependent not only on protease synthesis and its effect on crystal stability, but also on the aeration level of the production medium.

© 2002 Society of Chemical Industry
Potential of microbial growth control in water hydraulic systems by UV‐irradiation and filtration
Authors: Soini Sari M , Koskinen Kari T , Vilenius Matti J , Puhakka Jaakko A
Published: September 2002

Water hydraulic systems use water as a pressure medium and, thus, do not pose such adverse environmental impacts as oil hydraulics. Microbial deterioration of the pressure medium and biofouling of the surfaces restrict the applicability of the water‐based technology. The potential of microbial growth control by UV‐irradiation and filtration was studied in a pilot‐scale water hydraulic system. The UV‐irradiation (25 m Ws cm−2) of the pressure medium reduced the total viable counts of bacteria by 1–2 log10 cfu cm−3, whereas the total microbial cell numbers and the numbers of surface‐attached microorganisms remained unaffected. Prefiltration (1.2 µm, absolute) of the pressure medium decreased the total microbial cell number in the water phase and retarded the attachment of bacteria. The filtration during the operation (2 µm, absolute) decreased the total numbers of microbial cells and the total viable counts in the pressure medium, and microbial attachment on the surfaces. Microbial attachment was not prevented by filtration. The microbial water quality obtained by pre‐ and on‐line filtration of the pressure medium was sufficient to ensure the long‐term operation of the water hydraulic system assuming that clean work practices are complied with in assembly and during the operation.

© 2002 Society of Chemical Industry
Studies on precipitation of highly dispersed silica from sodium metasilicate–sodium hydrogencarbonate system
Authors: Żurawska Jolanta , Jesionowski Teofil , Krysztafkiewicz Andrzej
Published: September 2002

A novel procedure is presented for precipitation of highly dispersed silica from sodium metasilicate solution using sodium hydrogencarbonate. In the course of silica precipitation, hydrophobicity‐inducing agents were introduced to the reactor, including derivatives of saturated and unsaturated higher fatty alcohols and nonylphenylpolyoxyethyleneglycol ethers. Silicas of variable physicochemical characteristics were obtained. Analysis of the principal physicochemical properties of the silicas was performed, their surface morphology was examined using scanning electron microscopy while particle size distribution, polydispersity and tendency to form the agglomerate structures were estimated by the dynamic light scattering technique. The zeta potential was also measured by estimation of electrophoretic mobility. Sodium hydrogencarbonate solution was found to be a very good silica‐precipitating agent in solutions of sodium metasilicate. The hydrated silica obtained demonstrated low bulk density and a high capacity to absorb paraffin oil.

© 2002 Society of Chemical Industry
The differentiation of biodegradable and non‐biodegradable dissolved organic matter in wastewaters using fluorescence spectroscopy
Authors: Reynolds D M
Published: September 2002

The chemical and biochemical oxygen demand values of a number of synthetic and wastewater samples were determined using fluorescence spectroscopy. Treated and untreated sewage samples were obtained from a local sewage treatment works while synthetic samples were analysed before, during, and after treatment via a rotating biodisc contactor. Fluorescence intensities were normalised using the water Raman signal as an internal standard and corrections applied to take into account the attenuation effects caused by the sample matrix. The fluorescence emission spectra (λexc = 280 nm) of synthetic and sewage samples were very similar in that two main fluorescence bands centred around 350 nm and 440 nm were observed in all samples. Normalised fluorescence data, centred at 350 nm, correlate well with corresponding BOD, COD and TOC values (R2 values ranging between 0.93 and 0.98). Using BOD, COD and TOC data the fluorescence at 350 nm and 440 nm can be apportioned to biodegradable and non‐biodegradable dissolved organic matter respectively. The findings of this research show that fluorescence data can be used to quantify oxygen demand values (chemical and biochemical) and total organic carbon values. Furthermore, the fluorescence spectral response can be apportioned to biodegradable (BOD) and non‐biodegradable (COD − BOD) dissolved organic matter. The potential of using fluorescence spectroscopy as a possible tool for real‐time monitoring of sewage wastes is discussed.

© 2002 Society of Chemical Industry
Human liver‐derived cells stably modified for regulated proinsulin secretion function as bioimplants in vivo
Authors: Chen Xiang , Patil Jawahar G. , Lok Serene H. L. , Lian Kon Oi
Published: September 2002

Background

Insulin deficiency is currently treated with pharmacological insulin secretagogues, insulin injections or islet transplants. Secondary failure of pharmacological agents is common; insulin injections often fail to achieve euglycemic control; and islet transplants are rare. Non‐β cells capable of regulated insulin secretion in vivo could be a functional cure for diabetes. Hepatocytes are good candidates, being naturally glucose‐responsive, protein‐secreting cells, while the liver is positioned to receive direct nutrient signals that regulate insulin production.

Methods

Human liver‐derived Chang cells were modified with a plasmid construct in which a bifunctional promoter comprising carbohydrate response elements and the human metallothionein IIA promoter controlled human proinsulin cDNA expression. Secretory responses of stable cell clones were characterized in vitro and in vivo by proinsulin radioimmunoassay.

Results

Transfected Chang cells secreted 5–8 pmol proinsulin/106 cells per 24 h in continuous passage for at least a year in response to 5–25 mM glucose and 10–90 µM zinc in vitro. Glucose and zinc synergistically increased proinsulin production by up to 30‐fold. Non‐glucose secretagogues were also active. Glucose transporter 2 (GLUT2) and glucokinase cDNA co‐transfection enhanced glucose responsiveness. Intraperitoneally implanted Chang cells secreted proinsulin in scid and Balb/c mice. Serum proinsulin levels were further increased 1.3‐fold (p<0.05) after glucose and 1.4‐ to 1.6‐fold (p<0.005) after zinc administration in vivo.

Conclusions

These results are the first to demonstrate stable proinsulin production in a human liver‐derived cell line with activity in vitro and in vivo and provide a basis for engineering hepatocytes as in vivo bioimplants for future diabetes treatment. Copyright © 2002 John Wiley & Sons, Ltd.
Synthesis of L‐[4,5,5,5‐D4]isoleucine: determination of approximate rotamer population about the Cβ‐Cγ bond
Authors: Oba Makoto , Miyakawa Akiko , Shionoya Masanobu , Nishiyama Kozaburo
Published: September 2002

An asymmetric synthesis of regio‐ and stereoselectively deuterium‐labelled L‐isoleucine was examined. An unsaturated γ‐lactam readily available from L‐pyroglutamic acid was stereoselectively methylated by the Gilman reagent and subsequent oxidation of the hydroxymethyl moiety afforded a 3‐methylpyroglutamate derivative. Introduction of a deuterium atom into the γ‐position was achieved via a radical‐based deuteriation of the corresponding phenyl selenide by tributyltin deuteride. Then, the deuteriated 3‐methylpyroglutamate derivative was converted to L‐[4,5,5,5‐D4]isoleucine via a base‐promoted ring opening and a reductive deuteriation of the terminal carboxyl moiety. Copyright © 2001 John Wiley & Sons, Ltd.
Preparation of [2a,8a,10a,14a‐3H]geldanamycin by biosynthesis
Authors: Taylor George F. , Foarde Karin K. , Webber Tricia D. , Kepler John A.
Published: September 2002

[3‐3H]Propionic acid (1) was prepared by catalytic hydrogenation of 3‐bromo‐propionic acid with tritium gas. Fermentations of S. hygroscopicus were treated with 1 to produce [2a,8a,10a,14a‐3H]geldanamycin (2) with a specific activity of 76.2 mCi/mmol. The effect of the amount of 1 used and the dosing pattern on the specific activity of 2 was investigated. Copyright © 2001 John Wiley & Sons, Ltd.
Synthesis of hydroxyl silylated rhenium and (99mTc)technetium ‘3+1’ mixed ligand complexes
Authors: Kniess Torsten , Spies Hartmut , Santos Isabel , Zablotska Alla
Published: September 2002

The synthesis of hydroxyl silylated thiols as monodentate ligands is described. These monodentates were used to build with Re and 99mTc trimethyl‐, triethyl‐ and triphenyl‐silylated ‘3+1’ mixed ligand complexes, using 3thiapentane‐1,5‐dithiol as co‐ligand. The Re complexes were characterized by 1H NMR and elemental analysis, the 99mTc complexes were detected by radio HPLC. While the trimethyl silylated derivatives hydrolysed in aqueous media, the triethyl‐ and triphenyl silylated complexes have proved to be stable in neutral solutions. Copyright © 2002 John Wiley & Sons, Ltd.
Synthesis of doubly 13C‐labelled antalarmin isotopomers for pharmacokinetic studies
Authors: Greiner Elisabeth , Atkinson Arthur J. , Ayala Alejandro , Chrousos George P. , Contoreggi Carlo , Eckelman William C. , Gold Philip W. , Habib Kamal E. , Jacobson Arthur E. , Whittaker Noel , Webster Elizabeth L. , Rice Kenner C.
Published: September 2002

Antalarmin (butyl‐ethyl‐[2,5,6‐trimethyl‐7‐(2,4,6‐trimethyl‐phenyl)‐7H‐pyrrolo[2,3‐d]pyrimidin‐4‐yl]‐amine) was doubly labelled with carbon‐13. The synthesized butyl‐[13C2]ethyl‐[2,5,6‐trimethyl‐7‐(2,4,6‐trimethyl‐phenyl)‐7H‐pyrrolo[2,3‐d]pyrimidin‐4‐yl]‐amine (1) and butyl‐ethyl‐[2‐13C]‐[2,5,6‐trimethyl‐7‐(2,4,6‐trimethyl‐phenyl)‐7H‐pyrrolo[2,3‐d]‐[2‐13C] pyrimidin‐4‐yl]‐amine, (2) were prepared for use as substrates for pharmacokinetic studies. These compounds were obtained in fair overall yield in a 5 and 6 step synthesis (20–24.5%, respectively) and high isotopic purity (about 99 at% 13C). Copyright © 2002 John Wiley & Sons, Ltd.
Investigation of tyrosine nitration in proteins by mass spectrometry
Authors: Petersson Ann‐Sofi , Steen Hanno , Kalume Dário E. , Caidahl Kenneth , Roepstorff Peter
Published: September 2002

In vivo nitration of tyrosine residues is a post‐translational modification mediated by peroxynitrite that may be involved in a number of diseases. The aim of this study was to evaluate possibilities for site‐specific detection of tyrosine nitration by mass spectrometry. Angiotensin II and bovine serum albumin (BSA) nitrated with tetranitromethane (TNM) were used as model compounds. Three strategies were investigated: (i) analysis of single peptides and protein digests by matrix‐assisted laser desorption/ionization (MALDI) peptide mass mapping, (ii) peptide mass mapping by electrospray ionization (ESI) mass spectrometry and (iii) screening for nitration by selective detection of the immonium ion of nitrotyrosine by precursor ion scanning with subsequent sequencing of the modified peptides. The MALDI time‐of‐flight mass spectrum of nitrated angiotensin II showed an unexpected prompt fragmentation involving the nitro group, in contrast to ESI‐MS, where no fragmentation of nitrated angiotensin II was observed. The ESI mass spectra showed that mono‐ and dinitrated angiotensin II were obtained after treatment with TNM. ESI‐MS/MS revealed that the mononitrated angiotensin II was nitrated on the side‐chain of tyrosine. The dinitrated angiotensin II contained two nitro groups on the tyrosine residue. Nitration of BSA was confirmed by Western blotting with an antibody against nitrotyrosine and the sites for nitration were investigated by peptide mass mapping after in‐gel digestion. Direct mass mapping by ESI revealed that two peptides were nitrated. Precursor ion scanning for the immonium ion for nitrotyrosine revealed two additional partially nitrated peptides. Based on the studies with the two model compounds, we suggest that the investigation of in vivo nitration of tyrosine and identification of nitrated peptides might be performed by precursor ion scanning for the specific immonium ion at m/z 181.06 combined with ESI‐MS/MS for identification of the specific nitration sites. Copyright © 2001 John Wiley & Sons, Ltd.