bluuebunny/crossref_metadata_2025 huggingface dataset:
Network broadcast system using low bit‐rate audio coding technology
Authors: Kaneko Takao , Miki Satoshi , Moriya Takehiro , Iwakami Naoki
Published: January 2003

The VQVision network broadcast system, which can issue and distribute signals of high‐fidelity music and video images in real time based on the use of best‐effort networks that do not guarantee the transmission bandwidth of a LAN or the Internet, has been developed. Streaming signal distribution without sound interruptions has been realized by reducing the amount of data transmitted to about 1/18 to 1/88 of the original sound, without degrading the quality of music, by incorporating the TwinVQ low‐bit‐rate audio coding technology. This technology has been adopted as an ISO/IEC MPEG‐4/Audio International standard for compressed transmission processing of music. In addition, the speed of the music encoder has been increased by the newly developed multithreaded high‐speed encoder processing technology, and a self‐synchronizing scheme for renewing received images in synchronization with audio data packets has been designed and loaded. On the basis of these features, scheduled broadcasting or multicast live broadcasting of images and high‐fidelity music at bandwidths up to stereo CD bandwidth is performed by software developed without using dedicated encoder hardware and the like. Evaluations of the performance of this network broadcast system show that an encoder speed increase by a factor of up to 1.5 to 2 can be achieved by multithreading, and that high performance allowing simultaneous compression coding and transmission of a signal to a server in real time can be obtained even in live broadcasting in CD‐bandwidth stereo if dual CPUs operating at a clock frequency of 300 MHz are used. In addition, it has been found that network broadcasting signals composed of images at 15 frames/s and CD‐bandwidth stereo audio of a quality close to that of the original audio on a 512 kbit/s network band can be received without interruption, with a very small delay time of about 0.7 s from the time of its transmission. In addition, the reproduction timings of audio and images coincide exactly, even 24 hours from the beginning of signal reception. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 86(5): 89–102, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.10096
Impulse noise removal technique considering directional difference of image signal
Authors: Hashimoto Yuuhei , Kajikawa Yoshinobu , Nomura Yasuo
Published: January 2003

In the problem of restoration of images degraded by impulsive noise, a method has been proposed to eliminate impulsive noise by using the noise position image formed with noise detectors. However, such a method estimates the signal values of the pixels to be processed by using only the nondegraded pixels within the filter window. Hence, if the majority of the window is occupied by impulsive noise, the signal information needed for estimation becomes insufficient and the estimation accuracy is significantly reduced. In addition, in the previous method, average value filters and median filters are used for estimation of the signal value of the processing points. No processing has been included that takes account of the directionality (shape) of image signals such as edge components and detail components. In the present paper, a new noise elimination filter is proposed that attempts to improve restoration accuracy by addressing these two problems. In the proposed filter, first the degraded pixels within the filter window are precompensated for the problem of insufficient original signal pixels in the filter window, and then the signal values at the processing points are estimated by the filter once sufficient signal information is obtained. Preservation of the directionality of the image signals is improved by extending the directional difference filter. Its effectiveness is verified by real image processing results. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 86(5): 65–75, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.1149
An implementation of edge‐preserving filters using layered fuzzy controllers with learning
Authors: Wada Yuji , Muneyasu Mitsuji , Taguchi Akira , Hinamoto Takao
Published: January 2003

A filter using fuzzy inference has been proposed as a noise reduction filter for images with superposed mixed noise and its effectiveness has been demonstrated. When fuzzy inference is used, the optimization of its parameters is often a problem. For instance, Takashima and colleagues have proposed a configuration consisting of a cascaded connection of fuzzy controllers for impulsive noise and Gaussian noise. It is difficult to carry out optimization of both fuzzy controllers at the same time. In this paper, an optimization method is proposed for fuzzy controllers cascaded or connected in a layered manner. This method is applied to the fuzzy controller in the edge‐preserving nonlinear filter proposed by Takashima. In this way the structure is extended to a tunable filter. From the simulation results, it is found that the proposed method is effective for performance enhancement of the filter and is also effective for adjustment of fuzzy controllers connected in a layered manner. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 86(5): 76–88, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.1150
Characterisation of Chilean hazelnut (Gevuina avellana) tissues: light microscopy and cell wall polysaccharides
Authors: Dourado Fernando , Vasco Pedro , Barros António , Mota Manuel , Coimbra Manuel A , Gama Francisco M
Published: January 2003

By applying several differential staining techniques and light microscopy, the structure and composition of Chilean hazelnut (Gevuina avellana) seeds were analysed. The structure of the G avellana seed is very simple, with a thin, heavily lignified seed coat and two voluminous cotyledons. The embryo food reserves are uniformly distributed over the cotyledon cells. The cell wall polysaccharides were recovered from the alcohol‐insoluble residue by mild treatment with warm chlorite solution and sequential extraction with alkali solutions of increasing concentration. FT‐IR spectra in the 1200–850 cm−1 region were used together with chemometric techniques to distinguish the hemicellulosic and pectic polysaccharides in the extracts. The most abundant extracts were fractionated by graded precipitation in ethanol. A xyloglucan was identified by 1H and 13C NMR as the major hemicellulosic polysaccharide, with a sugar composition of 4Glc:3.5Xyl:1Gal:0.5Fuc. The hazelnut cell walls are composed of equivalent amounts of pectic polysaccharides, xyloglucans and cellulose.

© 2003 Society of Chemical Industry
Granulation sensing of first‐break ground wheat using a near‐infrared reflectance spectrometer: studies with soft red winter wheats
Authors: Pasikatan Melchor C , Haque Ekramul , Spillman Charles K , Steele James L , Milliken George A
Published: January 2003

A near‐infrared reflectance spectrometer, previously evaluated as a granulation sensor for first‐break ground wheat from six wheat classes and hard red winter (HRW) wheats, was further evaluated for soft red winter (SRW) wheats. Two sets of 35 wheat samples, representing seven cultivars of SRW wheat ground by an experimental roller mill at five roll gap settings (0.38, 0.51, 0.63, 0.75 and 0.88 mm), were used for calibration and validation. Partial least squares regression was applied to develop the granulation models using combinations of four data pretreatments (log(1/R), baseline correction, unit area normalisation and derivatives) and subregions of the 400–1700 nm wavelength range. Cumulative mass of size fraction was used as reference value. Models that corrected for path length effects (those that used unit area normalisation) predicted the bigger size fractions well. The model based on unit area normalisation/first derivative predicted 34 out of 35 validation spectra with standard errors of prediction of 3.53, 1.83, 1.43 and 1.30 for the >1041, >375, >240 and >136 µm size fractions respectively. Because of less variation in mass of each size fraction, SRW wheat granulation models performed better than the previously reported models for six wheat classes. However, because of SRW wheat flour's tendency to stick to the underside of sieves, the finest size fraction of these models did not perform as well as the HRW wheat models.

© 2003 Society of Chemical Industry
Starch and fibre distribution in maize silages in relation to particle size
Authors: Fernandez I , Michalet‐Doreau B
Published: January 2003

In a first trial the particle size distribution of four maize silages was measured by two different sieving methods, dry and wet sieving. Particle size distribution was quantified by three values, mean particle size, extent of dispersion, and proportion of large particles. Wet sieving separated particles better than dry sieving and was more suitable for measuring maize silage particle size. In a second trial the particle size distribution of 10 maize hybrids grown in the same conditions was measured by wet sieving. Starch proportion in large particles varied widely between maize hybrids, from 39.7 to 82.4%, against a variation from 75.4 to 100% for cell wall proportion in the same class of particles, and these variations might be predicted by dry matter distribution.

© 2003 Society of Chemical Industry
Tomatine, chlorophyll, β‐carotene and lycopene content in tomatoes during growth and maturation
Authors: Kozukue Nobuyuki , Friedman Mendel
Published: January 2003

Tomato (Lycopersicon esculentum) plants synthesise nutrients, pigments and secondary metabolites. These include the green pigment chlorophyll, the yellow pigment β‐carotene, the red pigment lycopene and the colourless glycoalkaloid α‐tomatine. The levels of these compounds are strongly influenced by the maturity of the tomatoes. Widely consumed Japanese tomato varieties Momotaro, Momotaro‐T93 and First Memory at five different stages of ripeness, each harvested at 10, 20, 30, 40 and 50 days after flowering of the plants, were analysed for the contents of these compounds. Additionally, tomato clusters from different locations along the vine on the same plant were also evaluated. The results show that chlorophyll and tomatine concentrations decrease rapidly during the growth of the tomatoes. By contrast, β‐carotene and lycopene levels are low in immature and high in mature tomatoes. The location of the tomato clusters and tomato variety did not significantly affect these results. The possible usefulness of these results to optimise health‐promoting effects of tomatoes is discussed.

© 2003 Society of Chemical Industry
Impact of mammalian enzyme pretreatment on the fermentability of carbohydrate‐rich feedstuffs
Authors: Bauer Eva , Williams Barbara A , Voigt Christina , Mosenthin Rainer , Verstegen Martin W A
Published: January 2003

Several carbohydrate‐rich substrates (spent brewer's grains, potato peel, potato starch, wheat bran, sugarbeet pulp and a maize‐based standard diet for pigs) were pretreated with digestive enzymes, and the in vitro fermentability of these treated substrates and their untreated counterparts was assessed using the cumulative gas production technique. A comparison was also made between the enzyme‐treated (ET) and untreated (UT) standard diet for pigs, and chyme which originated from pigs fed that diet, to determine whether the enzyme treatment resulted in material with similar fermentability to that reaching the large intestine in vivo. The enzyme pretreatment was performed according to a modified in vitro method of Babinszky et al (J Sci Food Agric 50:173–178 (1990)). Generally, it was shown that the fermentabilities of the ET and UT substrates were different. There was also a significant difference between the fermentation characteristics of the ET diet and chyme. Chyme produced less gas (P < 0.05), and the time at which half of the gas had been produced (C) occurred later (P < 0.05). The maximum rate of fermentation (R
M) was slower for chyme (P < 0.05). Fermentation of chyme led to more ammonia (P < 0.05) and a tendency to more volatile fatty acids at the end of fermentation. These differences in fermentability of the ET diet and chyme (from pigs fed the same diet) may be the result of differences which relate purely to the action of the enzymes chosen to work in vitro, compared with those which are actually present in vivo. However, the results also suggest that it is not only enzymatic digestion which is occurring in the small intestine. This is an important consideration when using ileal techniques to determine digestibility of feedstuffs.

© 2003 Society of Chemical Industry
Effect of gamma irradiation and sodium hydroxide treatment on the debittering of olive (Olea europaea) fruits
Authors: Al‐Bachir Mahfouze
Published: January 2003

The effect of gamma irradiation and sodium hydroxide (NaOH) treatment on the debittering of olive (Olea europaea, var Surrany) fruits was investigated. Fruits were treated with 1, 2 or 3 kGy of gamma irradiation at a dose rate of 669 Gy h−1. Irradiated and unirradiated fruits were processed with NaOH solution (11 g l−1) for 3 or 6 h and washed once per day for 3 days. The fruits were then immersed in brine (56 g l−1 sodium chloride) and stored for 12 months at room temperature. Dissolved organic and inorganic solids, Na+, K+ and Ca2+ contents, pH and electrical conductivity values were determined in the debittering solutions (lye, rinse and washing waters) and brines. Gamma irradiation significantly (p < 0.05) increased the dissolved organic and inorganic solids and the Na+ and K+ concentrations in the debittering solutions when the fruits were treated with NaOH for 3 h. On the other hand, gamma irradiation had no significant effect on these parameters, except for an increase in K+ concentration, when using NaOH solution for 6 h. Gamma irradiation with NaOH treatment for 3 h decreased the concentration of Ca2+ in the debittering solutions, whereas irradiation and treatment with NaOH solution for 6 h increased its concentration.

© 2003 Society of Chemical Industry
Stabilisation of colour and odour of beef patties by using lycopene‐rich tomato and peppers as a source of antioxidants
Authors: Sánchez‐Escalante Armida , Torrescano Gastón , Djenane Djamel , Beltrán José Antonio , Roncalés Pedro
Published: January 2003

Beef patties containing natural antioxidants—cayenne hot pepper, red sweet pepper, lycopene‐rich tomato pulp (LRTP) and extract of tomato rich in lycopene (Lyc‐O‐Mato™)—and packaged in modified atmosphere were evaluated for storage stability at 2 ± 1 °C by measuring CIE a* values, surface metmyoglobin, TBARS, psychrotrophic bacteria counts and sensory off‐odour and discolouration. Results demonstrated that the addition of ground peppers (both sweet and hot) to beef patties delayed and inhibited very significantly (p < 0.05) the oxidation of both myoglobin and lipid as well as the growth of psychrotrophic bacteria. As a consequence, and according to instrumental and sensory results of meat colour and odour, the shelf life of beef patties was extended from about 4 to about 16 days. Capsaicinoid‐rich cayenne hot pepper exerted a more intense antioxidative effect than capsaicinoid‐free red sweet pepper. The addition of lycopene‐enriched tomato products (LOM and LRTP) was not as effective as treatment with peppers, although they exerted a significant (p < 0.05) antioxidative effect too, depending on the lycopene concentration. These tomato products delayed meat deterioration to a varying extent, so that the shelf life of treated beef patties ranged between 8 and 12 days.

© 2003 Society of Chemical Industry
Effect of processing treatments on the characteristics of juices and still ciders from Ontario‐grown apples
Authors: Wilson Sarah M , Le Maguer M , Duitschaever C L , Buteau Carole , Allen O Brian
Published: January 2003

Recent interest in the commercial production of cider in Ontario, Canada revealed a lack of information on cider prepared from apples grown in North America. A study was conducted using locally grown culinary and dessert varieties of apples, since there is a lack of true cider varieties grown in Ontario. Four processing methods (treatments) were evaluated with respect to their effect on juice and cider characteristics; the chemical and microbiological characteristics of the juices and still ciders are reported. Sulphite addition to the juice at the time of juice extraction had no effect on the characteristics evaluated. Storage of fruits at 13 °C until they showed signs of shrivelling or senescence decreased juice yield and affected titratable acidity and pH levels of juices and ciders. Freezing fresh apples and thawing prior to processing produced juices that did not undergo keeving and had higher mould and yeast populations; methanol was present in juices and ciders from thawed apples. The significant effects of storage and freezing on apple juice characteristics should be taken into account when considering a delay in the processing of apples for cider production.

© 2003 Society of Chemical Industry
Occurrence of ochratoxin A in Greek wines
Authors: Soufleros Evangelos H , Tricard Christian , Bouloumpasi Elisavet C
Published: January 2003

The presence of ochratoxin A in foods and wines is of current interest owing to its toxic effects. Ochratoxin A is a widely distributed mycotoxin with nephrotoxic activity. It constitutes a new restrictive agent for the export of vinicultural products and is thus important from an economic as well as a scientific point of view. In this study the determination of ochratoxin A in Greek wines was made by means of commercial immunoaffinity columns for purification followed by HPLC with fluorescence detection for quantification of the toxin. The method was applied to 28 dry wines (14 red, 13 white, one rosé) and seven sweet wines (three red, four white) obtained by various viticultural and oenological practices. The levels of ochratoxin A ranged from <0.02 to 3.2 ng ml−1, with sweet wines containing higher levels than dry wines. Most of the wines contained relatively low concentrations of ochratoxin A (0.02–0.5 ng ml−1), which do not represent a serious risk to consumer health.

© 2003 Society of Chemical Industry
Dynamics of the co‐composting of barley waste with liquid poultry manure
Authors: Guerra‐Rodríguez E , Vázquez M , Díaz‐Raviña M
Published: January 2003

Co‐composting of barley waste with liquid poultry manure was assessed by monitoring several chemical and biological parameters related to compost stability/maturity throughout a 103 day period. A compost of solid poultry manure was used as the control, because a compost could not be obtained from the liquid manure. The materials composted reached thermophilic stage temperatures within 4 days, lasting for more than 10 days; thereafter the temperature decreased rapidly to around ambient levels. The initial pH value was around 9 for both mixtures and, despite an initial decrease, high values were maintained over the entire co‐composting process. Electrical conductivity increased with composting time, while the opposite behaviour was observed for total carbon content. Organic matter loss in the co‐composting of barley waste with liquid poultry manure was 35%. In general, the final products showed physicochemical characteristics considered normal for such materials, but pH and ammonia content values were high. The results of a bioassay test performed with seeds of three plant species (ryegrass, wheat and barley) indicated that the co‐compost could be considered mature from a biological point of view, since phytotoxicity was absent for ryegrass and barley. Comparison of these data with those obtained for solid poultry manure indicated that barley waste notably improved the composting efficiency as well as the quality of the final product.

© 2003 Society of Chemical Industry
Postharvest storage of Giant Cavendish bananas using ethylene oxide and sulphur dioxide
Authors: Williams Opal J , Raghavan G S V , Golden Kerith D , Gariépy Yvan
Published: January 2003

The potential of ethylene oxide (EO) and sulphur dioxide (SO2) to prevent ethylene‐stimulated fruit ripening was assessed using Giant Cavendish bananas. Studies were carried out in a cold room at 15 °C and terminated after 6 weeks. Product quality was assessed via visual observations and physiological assessments. Fruits were exposed to EO concentrations in the range 0–400 ppm for 12 h followed by storage in regular atmosphere (RA). Results showed that EO delayed ripening at 50 and 100 ppm for single exposure and at 50 and 200 ppm for repeated exposure. Treatment with 2 and 8 µg kg−1 SO2 was efficient in extending the shelf life of bananas for 4 weeks in RA and for 6 weeks under controlled atmosphere (CA). SO2 preserved the quality of bananas and reduced the incidence of fungal infections during storage; however, a concentration of 15 µg kg−1 shortened the shelf life. Fruits treated with low concentrations of EO and SO2 had harvest‐fresh appearance, good colour, minimum mould and excellent marketability compared with controls and store‐bought references. EO and SO2 are not approved for use on fresh fruits, with the exception of the use of SO2 on grapes and citrus fruits.

© 2003 Society of Chemical Industry
Influence of extraction temperature on the final quality of espresso coffee
Authors: Andueza Susana , Maeztu Laura , Pascual Lucía , Ibáñez Carmen , de Peña M Paz , Cid Concepción
Published: January 2003

The final quality of espresso coffee (EC) depends upon certain technical conditions, such as the extraction temperature used in preparing it. The aim of this work was to investigate the effects of water temperature (88, 92, 96 and 98 °C) on the final quality of three types of EC (Arabica, Robusta Natural blend and Robusta Torrefacto blend) in order to select the optimal temperature. Volatile compound (analysed by Static headspace gas chromatography/mass spectrometry) and sensory flavour profiles were the most relevant parameters, whereas physicochemical, taste and mouthfeel parameters were not very useful for selecting the water temperature. For Arabica and Robusta Natural blend ECs, 92 °C was the optimal water temperature. For Robusta Torrefacto blend EC the overall acceptability might lead to the selection of 88 °C as the ideal water temperature, but the high percentages of key odorants related to roasty and earthy/musty flavours and the ‘not hot enough’ perception dictated the selection of 92 °C in this case as well.

© 2003 Society of Chemical Industry
A reproducing kernel method with nodal interpolation property
Authors: Chen Jiun‐Shyan , Han Weimin , You Yang , Meng Xueping
Published: January 2003

A general formulation for developing reproducing kernel (RK) interpolation is presented. This is based on the coupling of a primitive function and an enrichment function. The primitive function introduces discrete Kronecker delta properties, while the enrichment function constitutes reproducing conditions. A necessary condition for obtaining a RK interpolation function is an orthogonality condition between the vector of enrichment functions and the vector of shifted monomial functions at the discrete points. A normalized kernel function with relative small support is employed as the primitive function. This approach does not employ a finite element shape function and therefore the interpolation function can be arbitrarily smooth. To maintain the convergence properties of the original RK approximation, a mixed interpolation is introduced. A rigorous error analysis is provided for the proposed method. Optimal order error estimates are shown for the meshfree interpolation in any Sobolev norms. Optimal order convergence is maintained when the proposed method is employed to solve one‐dimensional boundary value problems. Numerical experiments are done demonstrating the theoretical error estimates. The performance of the method is illustrated in several sample problems. Copyright © 2003 John Wiley & Sons, Ltd.
Non‐uniform plastic deformation of micron scale objects
Authors: Niordson Christian F. , Hutchinson John W.
Published: January 2003

Significant increases in apparent flow strength are observed when non‐uniform plastic deformation of metals occurs at the scale ranging from roughly one to ten microns. Several basic plane strain problems are analysed numerically in this paper based on a new formulation of strain gradient plasticity. The problems are the tangential and normal loading of a finite rectangular block of material bonded to rigid platens and having traction‐free ends, and the normal loading of a half‐space by a flat, rigid punch. The solutions illustrate fundamental features of plasticity at the micron scale that are not captured by conventional plasticity theory. These include the role of material length parameters in establishing the size dependence of strength and the elevation of resistance to plastic flow resulting from constraint on plastic flow at boundaries. Details of the finite element method employed in the numerical analysis of the higher order gradient theory will be discussed and related to prior formulations having some of the same features. Copyright © 2003 John Wiley & Sons, Ltd.
Voxel‐based meshing and unit‐cell analysis of textile composites
Authors: Kim Hyung Joo , Swan Colby C.
Published: January 2003

Unit‐cell homogenization techniques are frequently used together with the finite element method to compute effective mechanical properties for a wide range of different composites and heterogeneous materials systems. For systems with very complicated material arrangements, mesh generation can be a considerable obstacle to usage of these techniques. In this work, pixel‐based (2D) and voxel‐based (3D) meshing concepts borrowed from image processing are thus developed and employed to construct the finite element models used in computing the micro‐scale stress and strain fields in the composite. The potential advantage of these techniques is that generation of unit‐cell models can be automated, thus requiring far less human time than traditional finite element models. Essential ideas and algorithms for implementation of proposed techniques are presented. In addition, a new error estimator based on sensitivity of virtual strain energy to mesh refinement is presented and applied. The computational costs and rate of convergence for the proposed methods are presented for three different mesh‐refinement algorithms: uniform refinement; selective refinement based on material boundary resolution; and adaptive refinement based on error estimation. Copyright © 2003 John Wiley & Sons, Ltd.
Mesh deformation using the biharmonic operator
Authors: Helenbrook Brian T.
Published: January 2003

The use of the biharmonic operator for deforming a mesh in an arbitrary–Lagrangian–Eulerian simulation is investigated. The biharmonic operator has the advantage that two conditions can be specified on each boundary of the mesh. This allows both the position and the normal mesh spacing along a boundary to be controlled, which is important for two‐fluid interfaces and periodic boundaries. At these boundaries, we can simultaneously fix the position of the boundary and ensure that the normal mesh spacing is continuous across the boundary. In addition, results for deforming surfaces show that greater surface deformation can be tolerated when using biharmonic equations compared to approaches using second‐order partial differential equations. A final advantage is that with the biharmonic operator, the integrity of a grid in a moving boundary layer can be preserved as the boundary moves. The main disadvantage of the approach is its increased computational expense. Copyright © 2003 John Wiley & Sons, Ltd.
On the strong discontinuity approach in finite deformation settings
Authors: Oliver J. , Huespe A. E. , Pulido M. D. G. , Samaniego E.
Published: January 2003

Taking the strong discontinuity approach as a framework for modelling displacement discontinuities and strain localization phenomena, this work extends previous results in infinitesimal strain settings to finite deformation scenarios.

By means of the strong discontinuity analysis, and taking isotropic damage models as target continuum (stress–strain) constitutive equation, projected discrete (tractions–displacement jumps) constitutive models are derived, together with the strong discontinuity conditions that restrict the stress states at the discontinuous regime. A variable bandwidth model, to automatically induce those strong discontinuity conditions, and a discontinuous bifurcation procedure, to determine the initiation and propagation of the discontinuity, are briefly sketched. The large strain counterpart of a non‐symmetric finite element with embedded discontinuities, frequently considered in the strong discontinuity approach for infinitesimal strains, is then presented. Finally, some numerical experiments display the theoretical issues, and emphasize the role of the large strain kinematics in the obtained results. Copyright © 2003 John Wiley & Sons, Ltd.
Effect of soy protein isolate and conjugated linoleic acid on the growth of Dunning R‐3327‐AT‐1 rat prostate tumors
Authors: Cohen L.A. , Zhao Z. , Pittman B. , Scimeca J.
Published: January 2003

BACKGROUND

Epidemiologic and animal model studies suggest that consumption of soy isoflavones may be associated with reduced risk of prostate cancer (PC). In addition, animal model studies suggest that conjugated linoleic acid (CLA), a natural positional isomer of linoleic acid, inhibits tumor growth in various models, including models of PC.

METHODS

Based on the above‐mentioned data, the objective of the present study was to test the hypothesis that supplementation of the diet with combinations of isoflavone‐rich soy protein isolate and CLA would act to inhibit the growth of androgen‐independent R‐3327‐AT‐1 rat prostate tumor cells inoculated ectopically into male Copenhagen rats.

RESULTS

The results of this study indicate that neither an isoflavone‐rich soy protein isolate (SPI), nor CLA inhibit the in vivo growth and development of prostate tumor cells when administered in the diet either singly or in combination. Moreover, at the highest concentrations SPI and CLA (i.e., 20% SPI, 1% CLA), there was a statistically significant increase in tumors volume over controls. Administration of SPI at 10% in the diet also enhanced tumor growth, whereas at 5%, SPI exerted no measurable effect. CLA administration alone had no observable effects on AT‐1 tumor growth.

CONCLUSION

These results, in an established rat model, suggest caution in using isoflavone‐rich SPI in human studies involving advanced hormone‐refractory prostate cancer until further investigation of these effects are completed. Prostate 54: 169–180, 2003. © 2002 Wiley‐Liss, Inc.
Ionic and pharmacologic characteristics of epithelial cells in a semi‐intact preparation of the rat ventral prostate gland
Authors: Mycielska Maria E. , Szatkowski Marek , Djamgoz Mustafa B.A.
Published: January 2003

BACKGROUND

The essential ionic and pharmacologic characteristics of epithelial cells within the ducts of the prostate gland are not well known.

METHODS

Experiments were carried out on segments of ventral prostate glands from adult male rats. By using sharp microelectrodes, intracellular epithelial cell and transepithelial (lumen) potentials were recorded in response to ionic substitution and application of ion channel blockers, hormones, and other pharmacologic agents related to prostatic function.

RESULTS

Membrane permeabilities to K+, Na+, and Cl− were found to account for approximately 43% of the resting membrane potential, whereas some 39% was likely to be metabolic in origin. The membrane potential also responded to adrenaline, acetylcholine, insulin, prolactin, testosterone, nerve growth factor, and nitric oxide. The lumen potential was found to be particularly sensitive to citrate, prolactin, and testosterone.

CONCLUSION

It was concluded that the basal membrane potential of prostatic epithelial cells is associated with a relatively high Na+:K+ permeability ratio and metabolic dependence. The hormonal and pharmacologic sensitivity observed is consistent with the functional characteristics of the prostate gland. Prostate 54: 156–167, 2003. © 2002 Wiley‐Liss, Inc.
Expression of functionally active cannabinoid receptor CB1 in the human prostate gland
Authors: Ruiz‐Llorente Lidia , Sánchez María G. , Carmena María J. , Prieto Juan C. , Sánchez‐Chapado Manuel , Izquierdo Adriana , Díaz‐Laviada Inés
Published: January 2003

BACKGROUND

Cannabinoids exert a wide spectrum of effects in men including alterations in the reproductive system. To date, two types of cannabinoid receptors have been cloned in humans, namely CB1 and CB2 belonging to the G protein‐coupled receptor superfamily. Although cannabinoids have functional and morphologic effects in the prostate gland, the expression of cannabinoid receptors in this tissue has never been investigated. The aim of this study was to analyze the expression of cannabinoid receptors in the human prostate gland and their regulatory effects on adenylyl cyclase activity.

METHODS

To investigate the existence of cannabinoid receptors in prostate, we used various methods, including reverse transcriptase‐polymerase chain reaction, Western blotting, and immunohistochemistry. Adenylyl cyclase activity was analyzed by measuring the cAMP produced by means of a competitive assay by using PKA.

RESULTS

Both mRNA for CB1 and the corresponding protein are expressed in the human prostate gland at a level comparable with the receptor expressed in cerebellum. The molecular mass of the protein estimated from Western blot analysis was 58 kDa, which is in concordance with previous data for CB1 in other tissues. Immunohistochemical studies show that CB1 is preferentially expressed in the epithelia of the prostate. The cannabinoid receptor expressed in the prostate negatively regulates adenylyl cyclase activity through a pertussis toxin‐sensitive protein. Prostate 54: 95–102, 2003. © 2002 Wiley‐Liss, Inc.
Differential expression of the estrogen receptor beta (ERβ) in human prostate tissue, premalignant changes, and in primary, metastatic, and recurrent prostatic adenocarcinoma
Authors: Fixemer Thomas , Remberger Klaus , Bonkhoff Helmut
Published: January 2003

BACKGROUND

Estrogen signaling mediated by the estrogen receptor beta (ERβ) has potential implications in normal and abnormal prostate growth. Few studies have addressed this issue in human prostate tissue leaving conflicting results on the immunolocalization of the ERβ in benign and neoplastic lesions.

METHODS

Using a new monoclonal antibody, the current study reports on the differential expression of the ERβ in tissue sections from 132 patients with prostate cancer.

RESULTS

The prostatic epithelium expressed the ERβ extensively in secretory luminal cell types and at lower levels in basal cells. Atrophic changes of the peripheral zone (PZ) were more immunoreactive than hyperplastic lesions of the transition zone (TZ). When compared with glandular tissue of the PZ, high‐grade prostatic intraepithelial neoplasia (HGPIN) revealed decreased levels of the ERβ in 30 of 47 cases and was unreactive in six lesions. In informative cases with suitable internal controls, all primary tumors (n = 60), lymph node (n = 7), and bone metastases (n = 5) expressed the ERβ at variable degree. No correlation was found between the ERβ status, the primary Gleason grade (P = 0.254), and the pathological stage (P = 0.157). Recurrent adenocarcinoma revealed markedly decreased levels in 15 of 40 cases and was ERβ negative in five recurrent lesions.

CONCLUSIONS

The secretory epithelium is a major target of ERβ‐mediated estrogen signaling in the human prostate. Its downregulation in HGPIN is consistent with chemopreventive effects that the ERβ may exert on the prostatic epithelium. The continuous expression of the receptor protein at significant levels in untreated primary and metastatic adenocarcinoma indicates that these tumors can use estrogens through an ERβ‐mediated pathway. The partial loss of the ERβ in recurrent tumors after androgen‐deprivation may reflect the androgen‐dependence of ERβ gene expression in human prostate cancer. Prostate 54: 79–87, 2003. © 2002 Wiley‐Liss, Inc.
Clinical significance of chromosome 8p, 10q, and 16q deletions in prostate cancer
Authors: Matsuyama Hideyasu , Pan Yi , Yoshihiro Satoru , Kudren David , Naito Katsusuke , Bergerheim Ulf S.R. , Ekman Peter
Published: January 2003

BACKGROUND

We lack simple and reliable diagnostic tools to predict pathological staging as well as further progression of prostate cancer in individual cases.

METHODS

We studied deletions on 8p (8p22 and 8p23‐pter), 10q (10q24‐qter), and 16q (16q24) by fluorescence in situ hybridization in 53 specimens from patients with prostate cancer, and compared the status of these deletions with various clinical parameters. Forty‐five cases were further evaluated regarding disease progression with a median follow‐up period of 62 months.

RESULTS

The overall frequencies of deletions for 8p, 10q, and 16q were 74, 55, and 55%, respectively. The frequency of 8p and 16q deletions increased significantly in parallel with tumor grade (P < 0.01 and < 0.05, respectively), while that of 10q deletions did not. Patients whose tumors showed 8p22 deletions had a significantly higher frequency in pT3 or metastatic tumors than in pT2 tumors. Patients whose tumors showed both 8p22 and 16q24 deletions had a significantly higher frequency of nodal metastases than non‐metastases. A Cox hazard proportional model revealed 8p22 deletion to be the strongest parameter predictive of disease progression (hazard ratio = 6.624; P = 0.0001).

CONCLUSION

Estimation of 8p22 and 16q24 deletions may serve as a genetic diagnosis for predicting pathological staging as well as disease progression in prostate cancer. Prostate 54: 103–111, 2003. © 2002 Wiley‐Liss, Inc.
Prevalence of prostate cancer and prostatic intraepithelial neoplasia in Caucasian Mediterranean males: An autopsy study
Authors: Sánchez‐Chapado Manuel , Olmedilla Gabriel , Cabeza Manuel , Donat Emilio , Ruiz Antonio
Published: January 2003

Background

The prevalence of carcinoma of the prostate gland (CaP) and high‐grade prostatic intraepithelial neoplasia (HGPIN) was assessed in a Spanish population, representative of the Caucasian Mediterranean (CM) ethnic group. Data were compared with those described in populations from other geographical regions and in other ethnic groups.

Methods

CaP and HGPIN were evaluated in a consecutive series of prostatic glands collected at the post‐mortem examination of 162 male patients born and living in Spain, aged 20–80 years, and dying from trauma. The glands were sliced every 2–3 mm. All slices were paraffin embedded and sectioned to obtain 5 μm whole‐mount sections. To compare the prevalence rate in our series and in other Caucasian populations with that from other geographical areas and other ethnic groups, we used data from the autopsy study performed at the Wayne State University.

Results

Prevalence of CaP is 3.58, 8.82, 14.28, 23.80, 31.7, and 33.33% in the 3rd, 4th, 5th, 6th, 7th, and 8th decades, respectively. The rates of HGPIN were 7.14, 11.75, 35.71, 38.06, 45.40, and 48.15% at the 3rd, 4th, 5th, and 8th decades of life. Both CaP and HGPIN are located preferentially at the peripheral zone of the gland and in 21/27 cases (77.7%), an association between CaP and HGPIN was found. The prevalence of both lesions in CM males is significantly lower than in Caucasian American (CA) and Afro‐American (AA) males in all the age groups evaluated.

Conclusions

Microscopic foci of CaP and HGPIN can be documented in CM males from the 3rd decade of life onwards. The lesions become more frequent and extensive as age increases. The prevalence of both lesions seems to be significantly lower in the CM population than in CA and AA males in all the age groups evaluated. Prostate 54: 238–247, 2003. © 2002 Wiley‐Liss, Inc.
Down‐regulated expression of prostasin in high‐grade or hormone‐refractory human prostate cancers
Authors: Takahashi Satoru , Suzuki Shugo , Inaguma Shingo , Ikeda Yoshihisa , Cho Young‐Man , Hayashi Norio , Inoue Takahiro , Sugimura Yoshiki , Nishiyama Naoki , Fujita Tamio , Chao Julie , Ushijima Toshikazu , Shirai Tomoyuki
Published: January 2003

BACKGROUND

We previously conducted a search for genes which are differentially expressed in hormone‐refractory prostate cancers using cDNA‐representational difference analysis (RDA). The prostasin gene was isolated as one showing down‐regulation in hormone‐refractory cancers. In the present study, linkage to the stage in prostate neoplasia was examined.

METHODS

Prostasin expressions in 54 prostate cancer cases were examined by mRNA in situ hybridization and immunohistochemistry as well as by northern blot analysis.

RESULTS

Expression levels of prostasin in hormone‐refractory cancers were approximately one‐sixth of those in organ‐confined cancers by northern blotting. Glandular components in benign prostatic hyperplasia and high‐grade prostatic intraepithelial neoplasias tended to exhibit mild to moderate and relatively strong intensities, respectively. Expression levels of both prostasin mRNA and protein were inversely correlated with histological differentiation but not associated with clinical stage of human prostate cancer. Almost all cases of metastatic and hormone‐refractory cancers demonstrated down‐regulation of prostasin expression.

CONCLUSIONS

These results suggest that prostasin cannot be regarded as a prognostic indicator for human prostate cancer although it may be a useful marker for tumor differentiation. Prostate 54: 187–193, 2003. © 2002 Wiley‐Liss, Inc.
Quantitation of apoptotic activity following castration in human prostatic tissue in vivo
Authors: Staack Andrea , Kassis Adrienne P. , Olshen Adam , Wang Yuzhuo , Wu David , Carroll Peter R. , Grossfeld Gary D. , Cunha Gerald R. , Hayward Simon W.
Published: January 2003

Background

Androgen deprivation induces apoptosis in the prostate. Representative data, quantitating apoptotic activity in human prostatic epithelium following androgen ablation, are lacking.

Methods

Human prostatic tissue was grafted beneath the renal capsule of intact male athymic mice and allowed to become established. The mice were castrated and specimens were harvested on post‐castration day 0, 1, 2, 3, 4, 5, 7, 8, 9, 10, 14, 17, 18, and 21. Tissue was immediately fixed and apoptotic epithelial nuclei were identified.

Results

The percentage of terminal deoxynucleotidyl‐transferase‐mediated dUTP nick end‐labeling (TUNEL) positive epithelial cells increased from a baseline of 0.026%, peaked on post‐castration day 3 (1.54%), and returned to baseline by day 21. Mathematical analysis predicted that the observed apoptotic activity account for the loss of 87% of prostatic epithelial cells in 3 weeks.

Conclusions

Post‐castration apoptosis in human prostatic epithelium was low but was sufficient to account for the loss of nearly 90% of epithelial cells. Prostate 54: 212–219, 2003. © 2002 Wiley‐Liss, Inc.
The role of human glandular kallikrein 2 for prediction of pathologically organ confined prostate cancer
Authors: Haese Alexander , Graefen Markus , Becker Charlotte , Noldus Joachin , Katz Jared , Cagiannos Ilias , Kattan Michael , Scardino Peter T. , Huland Edith , Huland Hartwig , Lilja Hans
Published: January 2003

Background

In recent studies serum levels of human glandular kallikrein 2 (hK2) demonstrated significant differences in pathologically organ‐confined versus non‐organ‐confined prostate cancer (PCa). In this study we investigated whether hK2 adds independent information when considered together with traditionally used parameters to predict organ confined (pT2a/b) PCa.

Methods

Serum levels of hK2, total and free prostate‐specific antigens (PSA) were obtained one day before radical prostatectomy in 245 consecutive men. These were included with clinical stage and biopsy Gleason grade into univariate analysis and multivariate logistic regression models.

Results

pT2a/b PCa was found in n = 148 patients. In univariate analysis all preoperative parameters demonstrated significant association with the presence of pT2a/b PCa. Using multivariate logistic regression model hK2 (P = 0.022), clinical stage (P < 0.0001), and Gleason grade (P < 0.0001) were independent predictors of pT2a/b PCa whereas PSA (P = 0.3) was not. In bootstrap corrected logistic regression based nomograms the addition of hK2 density marginally enhanced predictive accuracy when PSA, PSA density, clinical stage, and Gleason grade were considered (AUC = 0.879 without hK2 density and 0.883 with hK2 density).

Conclusions

hK2 and hK2 density could independently predict pT2a/b PCa. However, improvement in predictive accuracy was marginal when nomograms based on traditional variables were complemented with this serum marker. Prostate 54: 181–186, 2003. © 2002 Wiley‐Liss, Inc.
Ribozyme‐mediated inhibition of PKCα sensitizes androgen‐independent human prostate cancer cells to cisplatin‐induced apoptosis
Authors: Orlandi Linda , Binda Mara , Folini Marco , Bearzatto Alessandra , Villa Raffaella , Daidone Maria Grazia , Zaffaroni Nadia
Published: January 2003

BACKGROUND

Therapeutic strategies to target the molecular basis of hormone and drug resistance of prostate cancer cells are needed. Since protein kinase Cα (PKCα) is thought to have a role in the development of the androgen‐independent phenotype of prostate cancer cells and in apoptosis suppression, the objective of the present study was to test whether specific inhibition of PKCα by a hammerhead ribozyme was able to sensitize androgen‐independent prostate cancer cells the effects of apoptosis‐inducing anticancer drugs.

METHODS

An active ribozyme (PKCαRZ) targeting codon 4 in human PKCα mRNA was synthesized by in vitro transcription. A mutant ribozyme (PKCαmutRZ) was also made by deleting G12 from the catalytic core of the active ribozyme and used as a control throughout the study. The double‐stranded, ribozyme‐encoding sequences were then inserted into an expression vector under the control of the cytomegalovirus promoter and delivered to growing prostate cancer cells (DU145 and PC‐3) by a DOTAP‐mediated transfer. A neomycin resistance gene on the vector was used to select ribozyme‐expressing clones. The clones were analyzed for PKCα expression, sensitivity to anticancer drugs and ability to undergo drug‐induced apoptosis.

RESULTS

Two DU145‐derived cell clones expressing the active ribozyme (DURZ 2 and DURZ 12) and one clone expressing the catalytically inactive ribozyme (DUmutRZ) were selected for the study. DURZ 2 and DURZ 12 were characterized by a markedly (about 40–50%) lower PKCα protein level than parental DU145 cells, whereas no reduction in PKCα expression was observed in DUmutRZ cells. Results of cytotoxicity experiments indicated that DURZ 2 and DURZ 12 but not DUmutRZ cells were significantly more sensitive than parental DU145 cells to a 1 hr exposure to the mononuclear platinum compounds (cisplatin and oxaliplatin) and showed an increased susceptibility to undergo cisplatin‐induced apoptosis. A significantly enhanced apoptotic response to cisplatin was also observed in a PC‐3‐derived polyclonal cell population endogenously expressing the active ribozyme.

CONCLUSIONS

Results of the study highlight the importance of PKCα in the response of prostate cancer cells to mononuclear platinum compounds and indicate specific inhibition of the enzyme as a potential therapeutic strategy to sensitize androgen‐independent prostate cancer cells to these drugs. Prostate 54: 133–143, 2003. © 2002 Wiley‐Liss, Inc.