bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of nickel‐activated catalytic filters for tar removal in H2S‐containing biomass gasification gas
Authors: Zhang Yuhong , Draelants Dirk J , Engelen Karen , Baron Gino V
Published: February 2003

The urea method was applied to deposit a nickel–calcium catalyst inside porous filter discs to develop a gas cleaning technique involving the combined removal of tars and particles from hot biomass gasification gas. Some catalytic filter discs were tested in typical filtration conditions for the decomposition of the model tar compound benzene in a simulated biomass gasification gas containing representative amounts of H2S. H2S‐deactivation studies showed a significant improvement in the sulfur resistance of the nickel catalyst on the filter discs by the addition of CaO to the catalyst formulation. The optimisation of the ratio between Ni and CaO and the effect of nickel content in the catalyst formulation on the catalytic performance were investigated.

© 2003 Society of Chemical Industry
Increasing gas–liquid contacting using a confined plunging liquid jet
Authors: Atkinson B W , Jameson G J , Nguyen A V , Evans G M
Published: February 2003

The plunging liquid jet bubble column is an effective device for gas–liquid contacting. Small bubbles are formed in a high‐shear region surrounding the plunging jet, leading to high interfacial area per unit volume of gas. At the same time, the counter‐current flow downstream of the jet leads to regions of high gas holdup, producing high interfacial area per unit volume of reactor. This paper presents a study of the void fraction in the pipe‐flow zone of the downcomer in a plunging jet reactor. It was found that the Ergun equation, using the standard constants derived from data for pressure drop in packed beds of solids, successfully predicted the gas void fraction for both bubbly and churn‐turbulent flow conditions provided the increase in bubble size, with increasing gas input, was taken into consideration. Drift‐flux analysis was also applied to the pipe‐flow zone, and highlighted the transition from bubbly to churn‐turbulent flow and a maximum gas void fraction operating condition of approximately 0.55. From the analysis the distribution coeffient for the downflowing system was found to be in the range 0.99–1.04, which was consistent with the measured radial void fraction profile and developed pipe flow for the two‐phase mixture.

© 2003 Society of Chemical Industry
Optimising activated sludge growth rate by intensifying hydrodynamic forces
Authors: Evans G M , Liu G
Published: February 2003

In this study a Couette device was used to examine the influence of hydrodynamic forces on the overall behaviour of activated sludge. The specific growth rate of activated sludge increased with increasing specific energy dissipation rate, reaching a maximum rate at an energy input of approximately 40 m2 s−3, beyond which any further increases resulted in a reduction in the overall growth. At levels above about 250 m2 s−3 the specific growth rate was negligible. Experimental growth rates in the range 0.04–0.20 h−1 were obtained, depending on the energy input levels and substrate (glucose) concentration. A theoretical model successfully predicted both the decrease in the floc radius and microbial activity with increasing energy input into the system, and when combined was able to provide a reasonable prediction for the optimum specific energy dissipation rate to maximise the specific growth rate.

© 2003 Society of Chemical Industry
Genetic strategy for solving chemical engineering problems in biochemical engineering
Authors: Yu Huimin , Shi Yue , Yin Jin , Shen Zhongyao , Yang Shengli
Published: February 2003

Genetic manipulation can be used to solve some traditional chemical engineering problems in biochemical engineering such as in poly(β‐hydroxybutyrate) (PHB) production. To reduce the high production costs of PHB resulting from expensive raw materials, low productivity of the process and complexity of recovery steps, PHB biosynthetic genes (phbCAB), Vitreoscilla globin gene (vgb) and lytic genes of phage λ with an S amber mutation (S−RRz) were simultaneously introduced into the same recombinant Escherichia coli, VG1 (pTU14). This will have the advantages of using phbCAB with cheap raw materials and accumulating a high content of PHB, with the ability of vgb to enable a higher specific oxygen uptake rate by the cells, and the characteristics of S−RRz to realize controllable cell lysis. In the fermentation of VG1 (pTU14), starch hydrolysate was used in place of glucose as a cheaper carbon source, and a PHB concentration and productivity as high as 167.6 g dm−3 and 3.05 g dm−3 h−1 were easily realized at almost zero levels of dissolved oxygen (DO), and with a simple temperature‐inducing treatment for recovery PHB with a purity of at least 95% was easily harvested.

© 2003 Society of Chemical Industry
Optimal operation of reactive simulated moving bed and Varicol systems
Authors: Yu Weifang , Hidajat K , Ray Ajay K
Published: February 2003

In this article, the performance of a reactive Simulated Moving Bed (SMB) and its modification, the more flexible Varicol process, is improved for the synthesis of methyl acetate (MeOAc) ester by multi‐objective optimization using Non‐dominated Sorting Genetic Algorithm (NSGA). The Varicol process is based on a non‐synchronous shift of the inlet and outlet ports instead of the synchronous one used in the traditional SMB technology. The optimization problems considered are both two‐ and three‐objective function problems. In one case, optimization was aimed at simultaneous maximization of the purity of MeOAc and minimization of adsorbent (and catalyst) requirement for the reactive SMB; while in the other case, maximization of purity and yield of MeOAc together with minimization of eluent (methanol) consumption for both reactive SMB and Varicol systems were considered. When the optimal solutions were compared, it was found that reactive Varicol systems could produce a higher purity product for a fixed yield, and consume slightly less eluent in the high purity region than more rigid SMB systems.

© 2003 Society of Chemical Industry
VOC–air separations using gas membranes
Authors: Everaert Kim , Degreve J , Baeyens Jan
Published: February 2003

Volatile organic components (VOC) are commonly emitted from chemical processes, ranging from dilute to concentrated streams. Membrane separation techniques are gaining increasing interest and acceptance for the recovery of VOCs. Various thin film composite membranes were experimentally assessed for the separation of gases and vapours. The membranes were used in a flat sheet configuration with a dense elastomeric silicone as the top layer on a porous polyether‐imide (PEI) or polyvinylidene‐fluoride (PVDF) support. Experimental results for pure substances and for binary mixtures were used to determine the permeability as a function of temperature and to calculate the selectivity towards nitrogen. Different models are available in the literature to predict the permeability of hydrocarbons and in this paper the free‐volume model is evaluated. The predictions from this model overestimate the experimental permeabilities, even after corrections through integrating the concentration polarisation and resistance of the porous support. A design method is developed to calculate the necessary surface area of the membrane separation module for a given flow rate, concentration, operating temperature and pressure, and the characteristic (experimental) permeability and selectivity of the membrane. This design is applied as an example to a butane–air system. Finally, current industrial applications are briefly reviewed.

© 2003 Society of Chemical Industry
Effect of NaCl precipitation on vapour–liquid dechlorination of CHClF2
Authors: Nishiumi Hideo , Kato Ryo
Published: February 2003

A dechlorination process for chlorinated compounds such as the chlorinated fluorocarbons (CFCs) is proposed. In this process, CFCs are dissolved in alcohols and irradiation with UV promotes their decomposition at room temperature and atmospheric pressure. Remarkably, irradiation is unnecessary to decompose chlorodifluoromethane, CHClF2 (HCFC22 or R22), which gives NaCl and 1,1‐difluorodimethyl ether CH3OCHF2 as products. In this work, experiments were carried out on the vapour–liquid reaction to produce the fluoroether CH3OCHF2 from HCFC22. The reaction was found to have no side reactions. The initial decomposition rate obtained from experimental results indicated that the reaction rate was proportional to the concentration of both NaOH and dissolved HCFC22. However, as the reaction proceeded, the reaction rate decreased more than expected from the initial reaction rate. Assuming that the produced NaCl precipitation created poor mixing of the methanol solutions, the volumetric coefficient KLa was measured and a model developed based on mass transfer relations. Calculated results showed that the model qualitatively agreed with the reaction rate data.

© 2003 Society of Chemical Industry
Dramatic innovation of propene epoxidation efficiency derived from a forced flow membrane reactor
Authors: Kobayashi Masayoshi , Togawa Junya , Kanno Tohru , Horiuchi Jun‐ichi , Tada Kiyosi
Published: February 2003

It is possible to develop a selective epoxidation process for propene using heterogeneous catalysis in a forced‐flow membrane reactor. The most innovative processes required two catalysts, Cs–Ag and Re–Ag, which were immobilized in the membrane pores of a micro‐porous glassy (MPG) substance, and three different reactor systems for reaction gas flows in the membrane pores. The systems included a convection‐flow reactor (CFR), a diffusion‐flow reactor (DFR), and a packed‐bed‐flow reactor (PFR). The three types were examined over temperatures ranges from 420 to 525 K, while keeping the total conversion of propene to less than 10%. The membrane reactor systems followed two common Langmuir‐type equations of reaction rates for CO2 and propylene oxide (PO) formation under steady state operations at atmospheric pressure. The amount of the intermediate for CO2 formation, whose structure retained the CCC bond of a propene molecule, was sensitively controlled by the types of catalysts and reactor systems used. Comparing the three immobilized catalysts, Cs–Ag, Re–Ag, and Ag2O, the larger the amount of intermediate formed on the catalysts the higher was the propylene oxide (PO) selectivity and thus the PO selectivity followed the order of Re–Ag > Cs–Ag > Ag2O. The CFR with Re–Ag/MPG clearly demonstrated hysteresis kinetics depending on the increase (C‐up) or decrease (C‐down) in the propene concentration. The PO selectivity was separately evaluated as 73–35% for the C‐up and 35–21% for the C‐down. The convection flow rate of reactants in the pores effectively contributed to an enhancement of the PO production rate from 18 to 41% of PO selectivity, for the reactant flow rate of 70–130 cm3 min−1 at 483 K.

© 2003 Society of Chemical Industry
Multi‐objective optimization of venturi scrubbers using a three‐dimensional model for collection efficiency
Authors: Ravi Gopalan , Viswanathan Shekar , Gupta Santosh K , Ray Madhumita B
Published: February 2003

Multi‐objective optimization of a venturi scrubber was carried out using a three‐dimensional model for collection efficiency and non‐dominated sorting genetic algorithm (NSGA). Two objective functions, namely (a) maximization of the overall collection efficiency, and (b) minimization of the pressure drop were used in this study. Three decision variables including two operating parameters, viz liquid–gas ratio and gas velocity in the throat, and the nozzle configuration, which takes into account the three‐dimensional nature of the problem, were used in the optimization. Optimal design curves (non‐dominated Pareto sets) and the values of the decision variables corresponding to optimum conditions on the Pareto set for a pilot‐scale scrubber were obtained. The liquid to gas (L/G) ratio, which is a key decision variable that determines the uniformity of liquid distribution, and a staggered nozzle configuration can produce uniform liquid distribution in the scrubber. Multiple penetration using nozzles of two different sizes in a triangular staggered arrangement can reduce liquid loading by as much as 50%, consequently reducing the pressure drop in the scrubber.

© 2003 Society of Chemical Industry
Process and product innovation
Authors: Mackley Malcolm
Published: February 2003

This paper gives an overview of the way process and product innovation has developed over the last 30 years. The background to innovation is considered by way of a few case studies. The changes that have occurred in the last 30 years are highlighted, and a possible pattern for the future outlined.

© 2003 Society of Chemical Industry
Performance enhancement of a chemical reactor utilizing flow instability
Authors: Kabir Mohammad F , Ray Ajay K
Published: February 2003

A detailed analysis has been performed for a heterogeneous photocatalytic Taylor vortex reactor that uses flow instability to recirculate fluid continually from the vicinity of the rotating inner cylindrical surface to the stationary outer cylindrical surface of an annulus. A comprehensive time accurate computation shows the different stages of flow evolution and the effects of finite length of the reactor in creating eddies, the overall effects of which shows very high efficiency of photocatalytic conversion. The physical arrangement considered is such that pollutant degradation is maximized by a combination of the Controlled Periodic Illumination (CPI) effect and the motion of fluid particles in a specific regime of centrifugal instability.

© 2003 Society of Chemical Industry
On modelling turbulent flow in an oscillatory baffled column – RANS model or large‐eddy simulation?
Authors: Jian Hongbing , Ni Xiong‐Wei
Published: February 2003

Oscillatory flow in a baffled column can achieve intensive and uniform mixing with lower shear rate in comparison to the traditional stirred tank reactors (STR). The flow in an oscillatory baffled column (OBC) is unsteady with periodicity in both time and space. Mixing is achieved by the formation of eddies. It is therefore very important to understand the turbulence in an OBC as it determines the degree of segregation, breakage of droplets and bubbles, and the efficiency of chemical/biochemical reactions. Modelling of turbulence is usually associated with the traditional Reynolds Averaged Navier–Stokes (RANS) model. Our results show that the RANS turbulence models, which are sufficiently good for simulating flows in STR, are very poor in predicting periodic flows in an OBC as the methodology of averaging in time in RANS has effectively removed the turbulence. In OBC, eddies of various sizes are the main ingredient for mixing, the large‐eddy simulation (LES) is particularly suitable for such type of flows. In this paper, we describe our understanding on the way in which the LES works.

© 2003 Society of Chemical Industry
Using non‐intrusive laser‐induced fluorescence in the characterisation of mixing in an oscillatory baffled column
Authors: Fitch A W , Ni X
Published: February 2003

Traditionally the characterisation of mixing in a system is achieved by injecting a tracer solution and monitoring the changes of tracer concentration with time using conductivity probes. In this paper we demonstrate that a non‐intrusive laser‐induced fluorescence (LIF) technique can be used to quantify the behaviour of viscous fluids in a model oscillatory baffled column (OBC). The OBC is an alternative‐mixing device in which longitudinal periodic fluid oscillations are transposed onto a column with evenly spaced ‘doughnut’ shaped baffles. This combination of baffles and oscillation generates an enhanced yet uniform mixing system. In LIF, a dye fluoresces when it is induced by a laser. The intensity of the light emitted can be converted into the concentration of the dye. The timed profile of average concentration (within a baffled cell) leads to the determination of the mixing time and axial dispersion coefficient. This paper attempts to show that LIF is a powerful tool in studying mixing.

© 2003 Society of Chemical Industry
Improved simulation of a vapour permeation module
Authors: Brinkmann Torsten , Dijkstra Marga , Ebert Katrin , Ohlrogge Klaus
Published: February 2003

An increasing number of hybrid processes consisting of conventional unit operations and vapour permeation modules have been suggested in recent years. To facilitate accurate process design, rigorous models of this novel membrane process are essential. By comparing experimental results obtained from a pilot plant, it was shown that simply solving the material balances and assuming constant permeances is not sufficient to predict the operating behaviour of a vapour permeation module. In order to reflect the experimental results it was necessary to consider the concentration, temperature and pressure dependency of the permeation process through the membrane as well as the mass transfer restriction in the boundary layer on the feed side. The introduced model is capable of taking account of these effects and predicts the experimental results satisfactorily. The model was written using the commercial, equation‐oriented process simulator Aspen Custom Modeler™ and hence can easily be integrated with commercial process simulation packages.

© 2003 Society of Chemical Industry
Process intensification of biodiesel production using a continuous oscillatory flow reactor
Authors: Harvey Adam P , Mackley Malcolm R , Seliger Thomas
Published: February 2003

Oscillatory flow reactors (OFRs) are a novel type of continuous reactor, consisting of tubes containing equally spaced orifice plate baffles. An oscillatory motion is superimposed upon the net flow of the process fluid, creating flow patterns conducive to efficient heat and mass transfer, whilst maintaining plug flow. Unlike conventional plug flow reactors, where a minimum Reynolds number must be maintained, the degree of mixing is independent of the net flow, allowing long residence times to be achieved in a reactor of greatly reduced length‐to‐diameter ratio. Many long residence time processes are currently performed in batch, as conventional designs of plug flow reactor prove to be impractical due to their high length‐to‐diameter ratios, which lead to problems such as high capital cost, large ‘footprint’, high pumping costs and, also control is difficult. The OFR allows these processes to be converted to continuous, thereby intensifying the process. The transesterification of various natural oils to form ‘biodiesel’ is a ‘long’ reaction, usually performed in batch. Conversion to continuous processing should improve the economics of the process, as the improved mixing should generate a better product (rendering the downstream separation processes easier), at lower residence time (reduction in reactor volume). These improvements can decrease the price of ‘biodiesel’, making it a more realistic competitor to ‘petrodiesel’. This paper shows that it is feasible to perform this reaction in an OFR at a lower residence time. The reaction was performed in a pilot‐scale plant, using rapeseed oil and methanol as the feedstocks, and NaOH as the catalyst.

© 2003 Society of Chemical Industry
Modelling a novel miniaturised reactor/separator system
Authors: Schuster Andreas , Lakshmanan Ramachandran , Ponton Jack , Sefiane Khellil
Published: February 2003

The use of microreactors for industrially relevant chemical production processes has been investigated. Recent research has shown that miniaturised reactors support process intensification and successful applications involve the synthesis of unit operations. Following a study of candidate processes for miniaturisation, this investigation focussed on the direct fluorination that consists of a complex set of reactions. A novel catalytic membrane microreactor configuration has been developed to address the contacting of the gas/liquid/solid phases. The membrane separates the gas phase from the liquid phase, presenting a well‐defined interface to the catalyst. A simplified model has been developed to study the advantages of the catalytic membrane for an isothermal parallel reaction system, where an electrophilic reaction leads to the desired product but competes with a fast radical reaction mechanism. If no catalyst is used the selectivity can be improved by limiting the fluorine concentration. The separation of the reactants results in higher selectivities at higher conversion compared with a mixed feed process (ie bubble column).

© 2003 Society of Chemical Industry
The use of pine bark as a natural adsorbent for persistent organic pollutants – study of lindane and heptachlor adsorption
Authors: Ratola Nuno , Botelho Cidália , Alves Arminda
Published: February 2003

Pine bark obtained as a sawmill by‐product in the north of Portugal was used for the adsorption of lindane and heptachlor, two organochlorine pesticides classified as POPs (Persistent Organic Pollutants), from aqueous solutions. It is intended that this natural adsorbent be used as an alternative to activated carbon in an innovative approach for the removal of these classes of compounds, reducing significantly the regeneration costs of the process, thus providing for its intensification. The analytical methodology validated for pesticides' quantification consisted of solid‐phase microextraction (SPME) prior to gas chromatography with electron capture detection (GC‐ECD), which presented limits of detection for lindane and heptachlor of 0.067 µg dm−3 and 0.062 µg dm−3, respectively. Repeatability, reproducibility and recovery were the parameters tested for validation, yielding better results for lindane. For the bark particle size used (125–300 µm), the average efficiency of removal attained for lindane was 80.6%, and 93.6% for heptachlor with the equilibrium time set at 24 h. Both Langmuir and Freundlich models were tested for the adsorption isotherm, but only the second approach produced reliable results for the adsorption parameters. Values obtained for log Kow were 3.17 for lindane (R2 = 0.9927) and 4.85 for heptachlor (R2 = 0.9401).

© 2003 Society of Chemical Industry
Experimental study on drag reduction in a duct
Authors: Mai Jianqiang , Früh Wolf‐Gerrit
Published: February 2003

The present study investigates drag forces on liquids pumped through a duct coated with a magnetic liquid of kinematic viscosity of 1.69 cSt. Due to a suitable arrangement of a set of permanent magnets, the magnetic liquid formed a fluid layer on the bottom of a square duct through which a silicone oil with a kinematic viscosity of 50 cst was pumped. Applied magnetic flux densities ranged from less than 0.01 T to about 0.15 T at the surface of the magnets. The influences of the strength and gradient of the magnetic field, and of the fluid flow rate, on the shape of the magnetic fluid have been investigated. It was found that it is not practical to form a uniform magnetic fluid layer under our experimental conditions, and consequently the drag was increased compared with the uncoated case because the flow of the silicone fluid over the magnetic fluid layer deformed this layer dramatically. For a viscosity ratio between the main flow and the ferrofluid less than about 30, it is therefore not feasible to use a magnetic fluid layer to reduce the drag in a duct. However, the generally high thermal conductivity of magnetic liquids, its convection, and interface deformation, might be exploited for heat transfer enhancement.

© 2003 Society of Chemical Industry
Competitive complexation/solvation theory of solvent extraction: general statements, acid extraction by amines, influence of active solvents and temperature
Authors: Kislik Vladimir , Eyal Aharon
Published: February 2003

A novel competitive complexation/solvation theory has been developed for interpretation, simulation and preliminary quantification of extraction systems. This theory is based on the modified competitive preferential solvation theory, the concept of amphoteric properties of extractants and the concept of the formation of different aggregation structures on increasing extractant loading. The theory establishes correlation between complexation and solvation. Co‐solvent independence allows direct comparison of the complexing/solvating power (competition order) of various solvents, used as extractants, enhancers (synergistic agents), and diluents. Once determined and tabulated, solute/solvent affinity constant ratio data may be used in any system containing these components. Mathematical descriptions of classical and the presented theories are compared and discussed. Some acid–amine extraction systems are analyzed based on the theory statements presented. The model provides a key for preliminary quantitative prediction of suitable extraction systems. Data, available from the literature and from experiments, were used.

© 2003 Society of Chemical Industry
Population balance modelling of droplets in an oscillatory baffled reactor—using direct measurements of breakage rate constants
Authors: Mignard Dimitri , Amin Lekhraj , Ni Xiong‐Wei
Published: February 2003

Population balance modelling (PBM) is a useful tool for design and prediction in a range of processes that involve dispersed phases, particulates or micro‐organisms. In the Inverse Problem approach, constants related to the rates of evolution and/or interaction of the individual components are optimized so as to match the experimentally observed distribution curves. However, the significance of these results may be slight, or several solutions may be possible. In this paper, a method is presented to circumvent this problem, and is applied to the breakage and coalescence of oil droplets in a continuous oscillatory baffled reactor (OBR). Direct observation of droplet breakage using a high‐speed camera should enable breakage rate constants to be obtained independently from the Inverse Problem approach, and thus obtain more reliable coalescence rate constants. An analysis of the droplet size distributions (DSDs) is also combined with direct observation with the high‐speed camera to allow the development of a breakage model specific to the OBR. It is expected that this method should yield parameters useful for prediction of steady‐state DSDs, and hence enhance the accuracy of design, scale‐up, and prediction of operation.

© 2003 Society of Chemical Industry
Particle‐scale modelling of gas–solid flow in fluidisation
Authors: Yu A B , Xu B H
Published: February 2003

Various approaches have been proposed to model the gas–solid two‐phase flow at different time and length scales, including the so‐called two‐fluid model (TFM), direct numerical simulation (DNS) and combined continuum and discrete model (CCDM). This paper briefly discusses the key features of these models and their relative merit with special reference to modelling gas fluidisation. Focus is then given to CCDM in which the motion of individual particles is obtained by solving Newton's second law of motion and fluid flow by the Navier–Stokes equation based on the concept of local average. The applicability of CCDM is highlighted by its successful simulation of complicated phenomena associated with the transition between fluid‐like and solid‐like behaviour in raceway formation and bed expansion. At the same time, the usefulness of the resulting particle‐scale information is demonstrated in elucidating the fundamentals governing the gas–solid flow. Finally, areas for future development are discussed.

© 2003 Society of Chemical Industry
Distribution of hepatitis B virus (HBV) genotypes among HBV carriers in the cote d'Ivoire: Complete genome sequence and phylogenetic relatedness of HBV genotype E
Authors: Suzuki Seiji , Sugauchi Fuminaka , Orito Etsuro , Kato Hideaki , Usuda Sadakazu , Siransy Liliane , Arita Isao , Sakamoto Yuko , Yoshihara Namiko , El‐Gohary Ahmed , Ueda Ryuzo , Mizokami Masashi
Published: February 2003

The characteristics of hepatitis B virus (HBV) genotype E are not well known because only a few studies have been carried out by complete genome analysis. The aim of this study was to elucidate the distribution of HBV genotypes in Cote d'Ivoire, and to clarify the genotype‐related characteristics of genotype E. The distribution of HBV genotypes among 48 HBV carriers in Cote d'Ivoire was determined using serological and genetic methods. The characteristics of genotype E were evaluated by complete genome sequences, and further investigations of small S gene, basic core promoter (BCP) mutation, and precore mutation were undertaken. HBV genotype distribution among the 48 carriers was 6.3% for genotype A, 6.3% for genotype D, and 87.4% for genotype E. Complete genomes of two genotype E strains were sequenced, and found to have 98.2% to 99.2% homology at the nucleotide level when compared with genotype E strains reported previously. In 24 genotype E carriers, the precore mutation was detected in 75% of the patients without HBeAg, in contrast to only 25% of the patients with HBeAg (P < 0.05). All 24 strains have T at nucleotide 1858 in the precore region. In contrast, BCP double mutation was detected in 17% of the patients with HBeAg, and 33% of the patients without HBeAg. These results indicated as the following: (1) genotypes A, D, and E of HBV exist in Cote d'Ivoire and genotype E is the most prevalent; (2) genotype E spread with low genetic diversity over the complete genome in West Africa; (3) HBV precore and/or BCP double variants were common among the patients with genotype E infections. J. Med. Virol. 69:459–465, 2003. © 2003 Wiley‐Liss, Inc.
Secular trend of age‐specific prevalence of hepatitis B surface and e antigenemia in pregnant women in Taiwan
Authors: Lin Ho‐Hsiung , Kao Jia‐Horng , Chang Ting‐Chen , Hsu Hong‐Yuan , Chen Ding‐Shinn
Published: February 2003

To elucidate the impact of aging of hepatitis B carrier women on their viral replicative markers in a hepatitis B endemic area, all the parturients admitted to the Hospital were studied from 1985 to 2000. Serum hepatitis B surface (HBsAg) and hepatitis B e antigen (HBeAg) were tested by radioimmunoassay. Mann‐Whitney U and Student's t‐tests were used for statistical analysis. The results showed the yearly prevalence rate of HBsAg in pregnant women seemed stable with a mean of 12.0 ± 1.1% during the period. The yearly positive rate of HBeAg among HBsAg‐positive pregnant women varied between 30.4% and 42.6% from 1985 to 1992 and declined from 29.6% in 1993 to 18.1% in 2000. The mean ratio of HBeAg/HBsAg in carrier parturients was 24.7% [intraquantile range (IQR) 20.5–28.4] from 1993 to 2000, which was significantly lower than that of 32.4% (IQR 31.0–39.0) from 1985 to 1992 (P < 0.0001). The mean age of HBeAg‐positive primiparas from 1993 to 2000 was 29.1 ± 3.9 years and significantly higher than that of 28.0 ± 3.7 years from 1985 to 1993 (P < 0.001), as well as in secundiparas 31.2 ± 3.8 years vs. 30.1 ± 3.4 years (P < 0.001) and in total parturients 30.3 ± 4.2 years vs. 29.3 ± 3.8 years (P < 0.001). Thus, no significant decrease of HBsAg carriage was observed in the past 16 years, whereas a decreased ratio of HBeAg/HBsAg was noted in carrier parturients in the past 8 years and the elderly HBeAg‐positive parturients from 1993 to 2000 may be the cause. J. Med. Virol. 69:466–470, 2003. © 2003 Wiley‐Liss, Inc.
Decline of hepatitis B carrier rate in vaccinated and unvaccinated subjects: Sixteen years after newborn vaccination program in Taiwan
Authors: Lin Hans Hsienhong , Wang Li‐Yu , Hu Chi‐Tan , Huang Shih‐Che , Huang Lu‐Chin , Lin Sherry S.J. , Chiang Yu‐Ming , Liu Tso‐Tsai , Chen Chien‐Lin
Published: February 2003

Taiwan was an endemic area for hepatitis B virus (HBV) infection, and related liver diseases cause a significant drain of public resources. To control the endemic, a nation‐wide newborn vaccination program was started in 1985. We reviewed the results of the annual survey for HBV surface antigen (HBsAg) performed in freshmen class of two high schools in Hualien, eastern Taiwan, from 1991 to 2001. A total of 10,194 students, most of them 15 years old, were tested for serum HBsAg using enzyme immunoassays. There is a significant trend (P < 0.0001) of decreasing HBsAg carrier rate from 20.3 to 4.4% in males and 14.3% to 2.4% in females, respectively, over 11 years. The HBsAg carrier rate was 16.0–20.3% in students surveyed during 1991–1993 (born more than 6 years before the start of the national vaccination program), which decreased to 7.7–11.9% during 1994–1999 (born 1–6 years before the program). It further declined to 4.7% and 3.4% in 2000 and 2001 (born after the start of the program). The HBsAg carrier rate in male students was significantly higher than that in female students in most of the years. The HBV newborn vaccination program not only successfully prevented most of the perinatal transmission of HBV but also reduced horizontal transmission of HBV to children born up to 6 years before the start of the program. Also, the protection persisted for at least 15 years. J. Med. Virol. 69:471–474, 2003. © 2003 Wiley‐Liss, Inc.
Sequencing of human‐viral DNA junctions in hepatocellular carcinoma from patients with HCV and occult HBV infection
Authors: Tamori Akihiro , Nishiguchi Shuhei , Kubo Shoji , Enomoto Masaru , Koh Noritoshi , Takeda Tadashi , Shiomi Susumu , Hirohashi Kazuhiro , Kinoshita Hiroaki , Otani Shuzo
Published: February 2003

DNA of free hepatitis B viruses (HBV) has been detected in the liver of patients infected with hepatitis C virus (HCV). It is unknown whether HBV DNA is integrated into such livers; if so, it may affect hepatocarcinogenesis. Hepatocellular carcinomas (HCCs) from 34 patients without HBV surface antigen (HBsAg) and with anti‐HCV, and from 7 patients with HBsAg and without anti‐HCV as controls, were examined, using the cassette‐ligation–mediated polymerase chain reaction and primers based on HBV DNA sequence. In the controls, HBV DNA had been integrated into human DNA of all HCCs. On the basis of HBV DNA in tumor tissue, 23 of the 34 patients with anti‐HCV had occult infection. Junctions between human DNA and HBV DNA were detected in 10 of the 34 patients without HBsAg and with anti‐HCV. HBV DNA was integrated into chromosome 11q in 4 of the 10 HCCs with junctions. The DNA to either side of the human‐viral junctions was sequenced. Clinically, the mean tumor size of these 10 HCCs was 39 mm; that of the 24 HCCs without integrated HBV was 25 mm. The surrounding tissue was cirrhotic in 2 of the 10 former HCCs and in 16 of the latter 24 HCCs. In conclusion, integrated HBV was detected in some patients with HCV infection; in these patients, the integrated DNA was associated with accelerated hepatocarcinogenesis. J. Med. Virol. 69:475–481, 2003. © 2003 Wiley‐Liss, Inc.
Evolution of hepatitis C virus quasispecies in renal transplant patients with de novo glomerulonephritis
Authors: Kamar Nassim , Rostaing Lionel , Boulestin Anne , Sandres Karine , Dubois Martine , Ribes David , Modesto Anne , Durand Dominique , Izopet Jacques
Published: February 2003

Long‐term renal allograft survival in kidney transplant recipients infected by hepatitis C virus (HCV) may be influenced by the occurrence of de novo glomerulopathy associated with this virus. Therefore, we studied the evolution of HCV quasispecies in kidney transplant recipients infected by HCV with or without de novo glomerulopathy. The hypervariable region 1 (HVR‐1) of the virus envelope was analyzed by cloning and sequencing 20 clones per sample to assess complexity and diversity from six kidney transplant patients who developed de novo glomerulopathy (group I) matched to six kidney transplant recipients without glomerular disease (group II), according to age, time since renal transplantation, and HCV genotype. Two sera were analyzed for each patient: one at the time of renal transplantation and the other at the time of appearance of de novo glomerulopathy, or after a similar duration since transplantation in group II. Overall, there was a significant increase of HCV viremia after the transplantation. This increase did not differ significantly between group I (+0.5 log copies/ml) and group II patients (+1 log copies/ml). The intersample diversity of HCV was similar in the two groups. Complexity and viral diversity were also similar at the time of transplantation. By contrast, complexity, diversity, and the proportion of nonsynonymous substitutions per nonsynonymous site were significantly higher after transplantation in group I patients. Our findings suggest a higher immune response and/or a particular cytokine production in patients developing de novo glomerulopathy rather than a direct effect of HCV on renal cells. J. Med. Virol. 69:482–488, 2003. © 2003 Wiley‐Liss, Inc.
Unexpected distribution of hepatitis C virus genotypes in patients on hemodialysis and kidney transplant recipients
Authors: Perez Renata M. , Ferraz Maria Lucia G. , Figueiredo Mauro S. , Contado Denilson , Koide Sandra , Ferreira Adalgisa P. , Cendoroglo Neto Miguel , Medina Pestana José O. , Silva Antonio Eduardo B.
Published: February 2003

The distribution of hepatitis C virus (HCV) genotypes in patients on hemodialysis and in kidney transplant recipients was compared with that observed in a control group composed of HCV‐infected individuals from the general population. A total of 340 patients were included in the study: 46 with end‐stage renal disease on regular hemodialysis treatment, 22 kidney transplant recipients and 272 controls matched for sex and age at a 4:1 ratio (controls to patient). HCV genotype was determined by sequencing of the 5′ untranslated region of the HCV genome. No difference was observed in the distribution of HCV genotypes in hemodialysis patients and renal transplant patients (P = 0.47). However, when each of these groups was compared with the control group, a significant difference was detected in the genotype distribution (P < 0.001). In hemodialysis and renal transplant patients the most prevalent subtype was 1a, followed by 1b, 3, and other less prevalent genotypes (2, 4, and 5), whereas in the control group the most prevalent subtype was 1b, followed by 3, 1a, and others. That observation may reflect differences in the epidemiology of HCV infection, viral characteristics and host factors in renal patients in comparison to the control group. J. Med. Virol. 69:489–494, 2003. © 2003 Wiley‐Liss, Inc.
Heparin‐interacting sites of bovine lactoferrin are involved in anti‐adenovirus activity
Authors: Di Biase Assunta Maria , Pietrantoni Agostina , Tinari Antonella , Siciliano Rosa , Valenti Piera , Antonini Giovanni , Seganti Lucilla , Superti Fabiana
Published: February 2003

Lactoferrin, a member of the transferrin family of ∼80 kDa, consists of a single polypeptide chain folded in two symmetric, globular lobes (N‐ and C‐lobes), each able to bind one ferric ion. This glycoprotein, found in physiological fluids of mammals, plays an important role in immune regulation and in defense mechanisms against bacteria, fungi, parasites, and viruses. Although the antiviral activity of lactoferrin is one of the major biological functions of such protein, the mechanism of action is still under debate. We have investigated both the role of tryptic fragments of bovine lactoferrin and the mechanism of lactoferrin antiviral effect toward adenovirus infection in HEp‐2 cells. The results obtained demonstrated that the anti‐adenovirus activity of lactoferrin is mediated by the N‐terminal half of the protein as the N‐lobe was able to inhibit adenovirus infection, even if at lower extent than undigested lactoferrin, whereas C‐lobe was ineffective. The results also showed that the anti‐adenovirus action of lactoferrin and of its N‐terminal peptide lactoferricin took place on virus attachment to cell membrane, mainly through competition for common glycosaminoglycan receptors. The data provide evidence that the anti‐adenovirus activity of lactoferrin is mediated mainly by the cluster of positive charges at the N‐terminus of whole molecule and that the N‐terminal peptide lactoferricin alone is sufficient to prevent infection. J. Med. Virol. 69:495–502, 2003. © 2003 Wiley‐Liss, Inc.
Polystyrene derivatives substituted with arginine interact with Babanki (Togaviridae) and Kedougou (Flaviviridae) viruses
Authors: Imbert‐Laurenceau Emmanuelle , Crepinior José , Crance Jean‐Marc , Jouan Alain , Migonney Véronique
Published: February 2003

Outbreaks of new or old diseases appear primarily in tropical zones such as Africa, south and central America, or Asia. Among these diseases, those induced by Arboviruses (the best known of which are being yellow fever, dengue, Ebola, and Sindbis) are under intensive observation by the World Health Organization. Rapid isolation and identification of the viral species is the first step in the diagnosis, study, and control of epidemics. One major problem with the isolation of viruses is capturing sufficient numbers of viral particles to test. The work presented in this report addresses this question. We have tested the interaction between Babanki (Togaviridae), Kedougou (Flaviviridae) viruses, and a range of insoluble polystyrene derivatives substituted with arginine groups. Insoluble functionalized copolymers were found to develop specific interactions with viruses through chemical groups present on their surfaces. The adsorption of viruses varied according to the percentage of arginine substituted onto the polymer, with a maximum value for both viruses of about 20% of grafting rate. It was also found that the Kedougou virus displayed the highest affinity for this polymer. J. Med. Virol. 69:503–509, 2003. © 2003 Wiley‐Liss, Inc.
Coxsackievirus immunization delays onset of diabetes in non‐obese diabetic mice
Authors: Davydova B. , Härkönen T. , Kaialainen S. , Hovi T. , Vaarala O. , Roivainen M.
Published: February 2003

Enteroviruses may be involved in the pathogenesis of Type 1 diabetes through different mechanisms including triggering of autoimmunity. The effect of immunization with coxsackievirus B4‐E2 on diabetes incidence was studied in the non‐obese diabetic mice, an animal model for human autoimmune insulin‐dependent diabetes mellitus. The immunization delayed the onset of diabetes in the mice, and the effect was mediated at least partially by virus immunization‐activated splenocytes as demonstrated by adoptive transfer experiments. Immunization resulted in a strong humoral immune response against the immunizing virus, formalin‐inactivated coxsackievirus B4‐E2. Cell‐mediated immune response to virus antigen was characterised by interferon gamma and interleukin 10 secretion. The immunization also resulted in increased antibody levels against several beta‐cell autoantigens. By using epitope mapping we were able to show that in addition to reactivity with the known epitopes of viral proteins and tyrosine phosphatase IA‐2 or heat shock protein 60, responses to some other regions of autoantigens were enhanced. In preproinsulin, the response was restricted against an antigenic region earlier identified as DR4‐dependent epitope. This reactivity can not be explained by homologous amino acid sequences and it is possible that enterovirus immunization might change the autoantigen specific TH1/TH2 balance in non‐obese diabetic mice. In conclusion, our results suggest that coxsackievirus immunization increased humoral immune response to beta cell autoantigens and this was associated with a less destructive pathology for spontaneous diabetes in non‐obese diabetic mice. J. Med. Virol. 69:510–520, 2003. © 2003 Wiley‐Liss, Inc.
Supernatants from dengue virus type‐2 infected macrophages induce permeability changes in endothelial cell monolayers
Authors: Carr Jillian M. , Hocking Helen , Bunting Karen , Wright Peter J. , Davidson Andrew , Gamble Jennifer , Burrell Christopher J. , Li Peng
Published: February 2003

The ability of dengue virus‐infected human monocyte‐derived macrophages to induce permeability changes in primary human umbilical vein endothelial cells was investigated. Supernatants from dengue virus type 2‐infected monocyte‐derived macrophages increased permeability in human umbilical vein endothelial cell monolayers without inducing endothelial cell infection. Production of permeabilising activity from monocyte‐derived macrophages occurred after the peak of progeny virus release. TNF‐α, a known inducer of endothelial cell permeability, was released from dengue virus infected monocyte‐derived macrophages but its release did not coincide with release of endothelial cell permeabilising activity. Permeability induction was enhanced by pre‐incubation with supernatants from infected monocyte‐derived macrophages harvested at the time of peak release of TNF‐α and infectious virus. Thus, supernatants from dengue virus‐infected monocyte‐derived macrophages contain factors that increase human umbilical vein endothelial cell permeability, but this is not accompanied by endothelial cell infection or directly correlated with release of dengue virus or TNF‐α from monocyte‐derived macrophages. This model system can be used for further in vitro analysis of mechanisms that may relate to capillary leakage and the development of dengue haemorrhagic fever/dengue shock syndrome. J. Med. Virol. 69:521–528, 2003. © 2003 Wiley‐Liss, Inc.
Molecular and biological analysis of echovirus 9 strain isolated from a diabetic child
Authors: Paananen Anja , Ylipaasto Petri , Rieder Elizabeth , Hovi Tapani , Galama Jochem , Roivainen Merja
Published: February 2003

The full‐length infectious cDNA clone was constructed and sequenced from the strain DM of echovirus 9, which was recently isolated from a 6‐week‐old child at the clinical onset of type 1 diabetes. Parallel with the isolate DM, the full‐length infectious cDNA clone of the prototype strain echovirus 9 Barty (Barty‐INF), was constructed and sequenced. Genetic relationships of the sequenced echo 9 viruses to the other members of the human enterovirus type B species were studied by phylogenetic analyses. Comparison of capsid protein sequences showed that the isolate DM was closely related to both prototype strains: Hill and Barty‐INF. The only exception was the inner capsid protein VP4 where serotype specificity was not evident and the isolate DM clustered with the strain Hill and the strain Barty‐INF with echovirus 30 Bastianni. Likewise, the nonstructural protein coding region, P2P3, of isolate DM was more similar to strain Hill than to strain Barty‐INF. However, like echovirus 9 Barty, the isolate DM contained the RGD‐motif in the carboxy terminus of capsid protein VP1. By blocking experiments using an RGD‐containing peptide and a polyclonal rabbit antiserum to the αvβ3‐integrin, it was shown that this molecule works as a cellular receptor for isolate DM. By using primary human islets, it was shown that the isolate DM is capable of infecting insulin‐producing β‐cells like the corresponding prototype strains did. However, only isolate DM was clearly cytolytic for β‐cells. The infectious clones that were made allow further investigations of the molecular features responsible for the diabetogenicity of the isolate DM. J. Med. Virol. 69:529–537, 2003. © 2003 Wiley‐Liss, Inc.