bluuebunny/crossref_metadata_2025 huggingface dataset:
Sperm‐derived activating ability does not persist in mouse oocytes inseminated during in vitro maturation
Authors: Ajduk Anna , Maleszewski Marek
Published: April 2004

Activity of the sperm‐derived oocyte‐activating factor persists in zygotes and can be detected by a fusion with metaphase II (MII) oocytes leading to the activation of the hybrids. We have shown, that in the great majority of oocytes inseminated 1–2 hr after germinal vesicle breakdown (GVBD) the sperm‐derived activating ability was eliminated. Only few hybrids produced by fusion of MII oocytes with oocytes inseminated during in vitro maturation (M × IVM‐P + sperm hybrids) underwent activation, whereas almost all of MII oocyte × zygote hybrids entered interphase. However, frequency of activation of M × IVM‐P + sperm hybrids was higher than that of control hybrids, which were obtained by fusion of MII oocytes with oocytes uninseminated during in vitro maturation. Although the difference was not statistically significant, it suggested that in a certain number of oocytes inseminated after GVBD the sperm‐derived oocyte‐activating factor remained partially active. This was confirmed by our observation that several oocytes, which were inseminated during in vitro maturation and managed to accomplish MII, underwent activation and formed pronuclei when examined 25–26 hr after the beginning of maturation. We have also demonstrated that parthenogenotes, could acquire the sperm‐derived activity, as a consequence of sperm injection. MII oocytes were fused with parthenogenotes inseminated by ICSI and all hybrids underwent activation. This result indicated that the ability to induce activation in hybrid, was sperm‐derived. Mol. Reprod. Dev. 68: 240–249, 2004. © 2004 Wiley‐Liss, Inc.
Active resource management for the differentiated services environment
Authors: Mahajan Manish , Ramanathan Ananthanarayanan , Parashar Manish
Published: April 2004

This paper presents a mechanism for active resource management (ARM) in a differentiated services environment. While the differentiated services architecture and the bandwidth broker agent provide a mechanism for QoS management through resource reservation, this mechanism is based on a static provisioning of resources. As bandwidth requirement are typically dynamic, such a static reservation approach can either lead to wasted bandwidth or leave applications resource‐starved. The active resource management approach presented in this paper addresses this problem by dynamically reallocating resources based on current network state and applications requirements. An implementation and evaluation of ARM using the NS‐2 simulation toolkit is also presented. Copyright © 2004 John Wiley & Sons, Ltd.
Scalable and lightweight key distribution for secure group communications
Authors: Lee Fu‐Yuan , Shieh Shiuhpyng
Published: April 2004

Securing group communications in dynamic and large‐scale groups is more complex than securing one‐to‐one communications due to the inherent scalability issue of group key management. In particular, cost for key establishment and key renewing is usually relevant to the group size and subsequently becomes a performance bottleneck in achieving scalability. To address this problem, this paper proposes a new approach that features decoupling of group size and computation cost for group key management. By using a hierarchical key distribution architecture and load sharing, the load of key management can be shared by a cluster of third parties without revealing group messages to them. The proposed scheme provides better scalability because the cost for key management of each component is independent of the group size. Specifically, our scheme incurs constant computation and communication overheads for key renewing. In this paper, we present the detailed design of the proposed scheme and performance comparisons with other schemes. Briefly, our scheme provides better scalability than existing group key distribution approaches. Copyright © 2004 John Wiley & Sons, Ltd.
Analyses of selected variables effecting video streamed over IP
Authors: Rosenthal David A.
Published: April 2004

The goal of this study was to understand the impact of certain variables effecting the transmission of video over Internet Protocol (IP) networks, utilizing data from Peak Signal‐to‐Noise Ratio (PSNR) and Picture Quality Rating (PQR) measurement metrics. Copyright © 2004 John Wiley & Sons, Ltd.
Foraging experience, glomerulus volume, and synapse number: A stereological study of the honey bee antennal lobe
Authors: Brown Sheena M. , Napper Ruth M. , Mercer Alison R.
Published: April 2004

The primary antennal sensory centers (antennal lobes) in the brain of the honeybee are highly compartmentalized into discrete spheres of synaptic neuropil called glomeruli. Many of the glomeruli can be identified according to their predictable size and location. This study examines T1‐44, a prominent glomerulus on the dorsal surface of the antennal lobe. Previously, we have shown that the volume of T1‐44 in 4‐day‐old workers performing tasks within the hive is significantly smaller than in foragers and that increases in volume are accompanied by an increase in total synapse number in this glomerulus. Here we examine whether foraging experience is essential for either changes in volume or for changes in synapse numbers in glomerulus T1‐44. Five‐day‐old bees reared under normal colony conditions were compared with 5‐day‐old bees reared under isolated conditions, and also to 5‐day‐old bees that had been induced to forage precociously. A combination of light and electron microscopy was used to compare T1‐44 volumes and synapse numbers in these three groups. Two groups of 11‐day‐old bees, precocious foragers and nonforagers, were also examined. The Cavalieri direct estimator of volume was applied to 1.5 μm sections of resin embedded brains. Selected sections were then re‐embedded and prepared for transmission electron microscopy. Synapse densities were determined using the physical disector method on electron micrographs. Synapse density and glomerulus volume were combined to give an unbiased estimate of the total number of synapses. This study shows that while both volume and synapse numbers can be induced to increase prematurely in young (5‐day‐old) precocious foragers, foraging experience is not essential for these structural changes to occur in glomerulus T1‐44. © 2004 Wiley Periodicals, Inc. J Neurobiol 60: 40–50, 2004
On the asymptotic solution of the Graetz‐Nusselt problem for short x → 0 and large x → ∞ with partial usage of finite differences
Authors: Campo Antonio
Published: April 2004

The principal goal of this article is to present two asymptotic solutions for the classical Graetz‐Nusselt problem. The method of lines (MOL) has been adopted for solving the governing partial differential energy equation in two independent variables in an asymptotic manner. Two temperature subfields are determined semianalytically: one for small x (x → 0) and the other for large x (x → ∞). Later, the two asymptotic mean Nusselt number subdistributions, NuX→0(x) and NuX→∞(x), blend themselves into a generalized correlation equation for the mean Nusselt number distribution Nu(x) covering the entire x‐domain. The simplicity of the MOL procedure, combined with the high quality asymptotic mean Nusselt number subdistributions, provides an alternative methodology for solving the Graetz‐Nusselt problem without using higher level mathematics. © 2004 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2004.
A mixed finite element method for a quasi‐Newtonian fluid flow
Authors: Farhloul M. , Zine A. M.
Published: April 2004

We propose a mixed formulation for quasi‐Newtonian fluid flow obeying the power law where the stress tensor is introduced as a new variable. Based on such a formulation, a mixed finite element is constructed and analyzed. This finite element method possesses local (i.e., at element level) conservation properties (conservation of the momentum and the mass) as in the finite volume methods. We give existence and uniqueness results for the continuous problem and its approximation and we prove error bounds. © 2004 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2004.
Cleavage of AL amyloid proteins and AL amyloid deposits by cathepsins B, K, and L
Authors: Bohne Silvia , Sletten Knut , Menard Robert , Bühling Frank , Vöckler Steffi , Wrenger Eike , Roessner Albert , Röcken Christoph
Published: April 2004

Cathepsin (Cath) B, CathK and CathL are cysteine proteases that participate in the lysosomal protein degradation system and are expressed in macrophages, epithelioid cells, and multinucleated histiocytic giant cells (MGCs). Both macrophages and MGCs are commonly found adjacent to immunoglobulin light chain‐associated (AL) amyloid deposits, which raised the question of whether cysteine proteases are able to cleave AL amyloid proteins and AL amyloid deposits. The present study has investigated whether recombinant human CathB, CathK, and CathL are able to degrade ALVλVI amyloid proteins and AL amyloid deposits. Using immunohistochemistry, CathB, CathK, and CathL were found adjacent to AL amyloid deposits. In vitro degradation experiments using purified AL amyloid proteins showed that CathB, CathK, and CathL degrade ALVλVI amyloid proteins. Furthermore, using unfixed tissue sections from an amyloidotic spleen as an in vitro model for extracellular proteolysis of intact amyloid deposits, it was demonstrated that all three cysteine proteases are also capable of degrading AL amyloid in situ. This is the first study to show that cysteine proteases are able to cleave AL amyloid proteins. However, the efficiency with which proteolysis occurs depends on the concentration of active protease recruited at the sites of amyloid deposition, and possibly on the structure of the AL amyloid proteins. Copyright © 2004 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Drug counselling in pregnancy: an opinion survey of French community pharmacists
Authors: Damase‐Michel Christine , Vié Céline , Lacroix Isabelle , Lapeyre‐Mestre Maryse , Montastruc J. L.
Published: April 2004

Purpose

The aim of the present study was to determine whether community pharmacists recommend appropriate medications and give valid information to pregnant women.

Methods

A total of 163 community pharmacists randomly selected in the Midi‐Pyrénées area were interviewed by means of an open questionnaire. Ten scenarios were proposed concerning back pain, headache, coughs and sore‐throats, fever, constipation, nausea, dyspepsia, ‘venous insufficiency’, allergic rhinitis and insomnia.

Results

Out of the total, 130 pharmacists accepted to answer. Out of them 94.5% reported advising homeopathy, especially for coughs and allergy. They often advised medication for pain, fever, nose and oropharynx disorders, ‘venous insufficiency’, dyspepsia or constipation. By contrast, they referred the women to the general practitioner for nausea and vomiting or back pain. Advice without drug dispensation was given for gastrointestinal disorders or ‘venous insufficiency’. Phytotherapy only concerned 0.5–2% of the answers except for anxiety and sleep disturbances (59%), ‘venous disorders’(17%) and sore‐throat (9%). Pharmacists' answers were sometimes inappropriate involving (1) pharmacologically illogical advice, (2) drugs for which neither clinical nor experimental data are available and (3) drugs potentially harmful in pregnancy.

Conclusions

The present study shows that French community pharmacists do not always give appropriate advice to pregnant women. As primary health care providers, pharmacists have to improve counselling regarding drug use in pregnancy. Copyright © 2004 John Wiley & Sons, Ltd.
Influence of the cure level on the monomeric friction coefficient of natural rubber vulcanizates
Authors: Marzocca Angel J , Steren Carlos A , Raimondo Roxana B , Cerveny Silvina
Published: April 2004

An experimental investigation was performed in order to correlate the changes observed in dynamic modulus and loss tangent of vulcanized natural rubber with its network structure. A set of samples of natural rubber vulcanized at 413 K and 433 K for different times was prepared to achieve different network structures in the compound material. These networks were analyzed by means of solid‐state NMR techniques in order to distinguish the sulfur bridges formed during vulcanization. The crosslink density was calculated using swelling techniques for each cure condition. Dynamic mechanical tests were performed using a free decay pendulum in the range of temperatures between 213 K and 373 K and oscillating frequencies between 0.1 s−1 and 20 s−1. Loss tangent data were analyzed within the frame of the KMF model and the variation of the monomeric friction coefficient with the crosslink density was obtained. This variation is a consequence of the network structure formed in the different stages of the curing process. Copyright © 2004 Society of Chemical Industry
In‐depth characterization of granular starch‐graft‐polyester compositions as obtained by in situ polymerization of lactones from the starch surface
Authors: Rutot‐Houzé Delphine , Degée Philippe , Gouttebaron Rachel , Hecq Michel , Narayan Ramani , Dubois Philippe
Published: April 2004

The synthesis of poly(ε‐caprolactone) (PCL)‐grafted granular starch was carried out either in bulk (without solvent) or in toluene suspension by a two‐step procedure. First step relied upon the activation of the hydroxyl groups available at the starch surface by alkylaluminum derivatives like AlEt3 and removal of non‐surface‐grafted organo‐aluminum active species. The latter species were made free in solution by reaction with the remaining water molecules still contaminating the polymerization medium despite intensive drying of the starch granules. In the second step, ε‐caprolactone was polymerized via a coordination‐insertion ring‐opening polymerization as initiated by the surface‐grafted aluminum alkoxide species. The present contribution aims at investigating various parameters such as nature of the alkyl aluminum activator and monomer (δ‐valerolactone was studied as well), temperature, concentration, and addition of a solvent (polymerization in toluene suspension), reaction time, and also the experimental procedure used to recover the polyester chains and measure the grafting efficiency. It turns out that, under the studied conditions, dialkylaluminum alkoxides surface‐grafted onto the starch granules were more likely generated and promote a fast polymerization reaction with the formation of grafted PCL chains with a molecular weight that can be as high as 225 000 (Mn value) for polymerization carried out in toluene suspension. Copyright © 2004 Society of Chemical Industry
Crystallization and solid‐state polymerization of poly(aryl ester)s
Authors: James Nirmala R , Ramesh C , Sivaram S
Published: April 2004

The crystallization and solid‐state polymerization (SSP) of poly(aryl ester)s was investigated. Oligomers with different end‐groups were prepared by degradation of commercially available poly(aryl ester)s. The SSP of these oligomers was carried out after crystallization and under reduced pressure, in the presence of various catalysts. Polymers were characterized by means of their inherent viscosities and thermal properties. It has been found that Ti(OiPr)4 was a better catalyst for SSP. The structures and morphologies of semicrystalline poly(aryl ester)s were investigated by X‐ray diffraction and differential scanning calorimetry (DSC). Copyright © 2004 Society of Chemical Industry
A versatile computer‐controlled high‐resolution LBIC system
Authors: Martín J. , Fernández‐Lorenzo C. , Poce‐Fatou J. A. , Alcántara R.
Published: April 2004

This paper presents the design of versatile equipment for obtaining laser‐beam‐induced current (LBIC) images which allows the study of large surfaces as well as conversion areas of a few micrometers. The modular optomechanical design enables the user to modify the size of the irradiation spot by simply changing the microscope objective used as focal lens, albeit within the limits set by the wavelength. The use of an appropriate calculation algorithm makes it possible to rely on a computerized system to adjust the distance at which the focusing lens must be placed with respect to the sample plane. The possibility of working at micrometer resolution allows one to obtain very significant information for the study of irregularities, manufacturing defects, impurities, grain boundaries, dislocations, recombination centers, etc. in photovoltaic wafers. Copyright © 2004 John Wiley & Sons, Ltd.
Plastic deformation of glassy polystyrene: A unified model of yield and the role of chain length
Authors: Wu J. J. , Buckley C. P.
Published: April 2004

A study was made of yield and plastic flow in glassy polystyrene. A range of 12 linear atactic polystyrenes was studied: monodisperse, bimodal blends, and a polydisperse commercial sample. Mn varied between 66,000 and 490,000 g/mol. These were given standardized thermal treatments and then subjected to uniaxial compression tests in the glassy state over the temperature range 40 to 95 °C and nominal strain‐rates 10−4 to 10−3 s−1. Their constitutive responses were interpreted in terms of the physically based three‐dimensional constitutive model for small or large deformations in amorphous polymers proposed earlier (Polymer 1995, 36, 3301–3312), including plastic strain‐induced structural rejuvenation. In multimode form, the model captured closely both linear viscoelastic response and yield and plastic flow. When the reduction of Vogel temperature caused by chain ends was incorporated in the model, it predicted a fall in yield stress with reducing molecular length. This was also observed in experimental data, with the rate of fall approximately in agreement. The results provide further support for the model as a unifying framework for describing the physical properties of polymer glasses. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2027–2040, 2004
Strain hardening of polycarbonate in the glassy state: Influence of temperature and molecular weight
Authors: Govaert L. E. , Tervoort T. A.
Published: April 2004

This study is concerned with the temperature and molecular weight dependence of the strain‐hardening behavior of polycarbonate. It is shown that the strain‐hardening modulus reduces with increasing temperature and decreasing molecular weight. This result is interpreted in terms of temperature accelerated relaxation of the entanglement network. Moreover, it is shown that frozen‐in orientations, induced by homogeneous deformations above the glass transition temperature, lead to anisotropic yield behavior that can be fully rationalized (and modelled) in terms of a superimposed stress contribution of the prestrained network. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2041–2049, 2004
Quality of life, self‐esteem and worries in young adult survivors of childhood cancer
Authors: Langeveld N.E. , Grootenhuis M.A. , Voûte P.A. , de Haan R.J. , van den Bos C.
Published: April 2004

This study assessed quality of life, self‐esteem and worries in young adult survivors of childhood cancer compared to a group of young adults with no history of cancer. The impact of demographic, medical and treatment factors and self‐esteem on survivors' quality of life and worries was studied.

Participants were 400 long‐term survivors (LTS) of childhood cancer (age range 16–49 years, 45% female) who had completed treatment an average of 16 years previously and 560 persons (age range 16–53 years, 55% female) with no history of cancer. All participants completed the MOS‐24 (Medical Outcome Study Scale), a Worry questionnaire consisting of three scales (cancer‐specific concerns, general health concerns, present and future concerns), and the Rosenberg Self‐Esteem Scale.

Small to moderate differences were found in mean MOS‐24 scores between the LTS group and controls (range effect sizes −0.36–0.22). No significant difference was found in the mean self‐esteem scores between LTS and controls. Female LTS had more cancer‐specific concerns than male LTS. In several related areas of general health, self‐image and dying, the LTS group reported less worries than controls, but LTS worried significantly more about their fertility, getting/changing a job and obtaining insurance's. Multiple linear regression analysis revealed that female gender, unemployment, severe late effects/health problems and a low self‐esteem were predictors of worse quality of life in survivors. In addition, age at follow‐up, unemployment, years since completion of therapy and a low self‐esteem were associated with a higher degree of survivors' worries.

Quality of life and the level of self‐esteem in LTS of childhood cancer is not different from their peers. Although many LTS worried not more or even less about health issues than their peers, they often are concerned about some present and future concerns. The investigated factors could explain poor quality of life and worries only to a limited extent. Further research exploring determinants and indices of quality of life and worries in LTS is warranted. Copyright © 2004 John Wiley & Sons, Ltd.
Relationships between patients' pre‐treatment expectations of toxicities and post chemotherapy experiences
Authors: Olver Ian N. , Taylor Anne E. , Whitford Hayley S.
Published: April 2004

A lack of adequate pharmacological explanations for side effect variation following chemotherapy suggests psychological factors may contribute to toxicity experience. This research aimed to determine if patients' expectations were associated with perceived toxicities for a wider range of chemotherapy toxicities than previously researched, including subjective and objective side effects. Eighty‐seven chemotherapy‐naïve patients rated their expectations of 20 common side‐effects before treatment, and then rated their experiences following their first chemotherapy dose. Hierarchical multiple regression analyses revealed that expectations of the inability to concentrate, hair loss, and diarrhoea prior to treatment had the strongest associations with the experience of symptoms. Expectations of encountering problems with sleep and sex, changes in taste or appetite, weakness, and nervousness, all showed moderate associations, and expectations of mood changes, feelings of tiredness, and nausea all showed weak associations with experience. These outcomes suggest that subjective side effects may be more prone to influence by expectation given their ambiguous nature. However, further research needs to be conducted into the effect expectations have on the treatment process, including the impact of other psychological factors. The current overriding emphasis placed on personal autonomy and fully informed consent may set up negative expectations which translate into adverse experiences to the detriment of the patient. Copyright © 2004 John Wiley & Sons, Ltd.
Thermokarst as a short‐term permafrost disturbance, Central Yakutia
Authors: Brouchkov Anatoli , Fukuda Masami , Fedorov Alexander , Konstantinov Pavel , Iwahana Go
Published: April 2004

The widespread occurrence of alas depressions in Central Yakutia is not necessarily evidence of modern thermokarst activity. Typically, a near‐surface ‘shielding layer’, formed as the result of deep thaw in exceptionally warm years, protects underlying icy sediment from thaw. In spite of current climatic warming, there is no noticeable increase in regional thermokarst in Central Yakutia. Periodic forest fires significantly increase soil thermal conductivity and progressive soil salinization is occurring; however, these are insufficient to cause thaw of the underlying icy sediments. Instead, active thermokarst should be regarded as a short‐term catastrophic process. Use of the Kudryavtsev algorithm indicates that the depth of thaw beneath a water body in Central Yakutia can reach 8–10 m within 50 years, and 20+ m within 300 years. Field observations show that current thermokarst has a tendency for fast (5–10+ cm/year) subsidence. Copyright © 2004 John Wiley & Sons, Ltd.
Sedimentology and facies distribution of Pleistocene cold‐climate aeolian and fluvial deposits in the Roer Valley Graben (southeastern Netherlands)
Authors: Schokker Jeroen , Koster Eduard A.
Published: April 2004

The Roer Valley Graben (southeastern Netherlands) is an area of tectonic subsidence that contains a 35 m‐thick record of fine‐grained Middle‐ and Upper‐Pleistocene deposits. The sedimentary structures of these sediments were studied using undisturbed sediment cores and cone penetration tests. This enabled a reconstruction of the depositional environment. Seven sedimentary facies were distinguished, ranging from sandy fluvial deposits to loamy aeolian deposits and organic sediments. Wet‐aeolian sand‐sheet and loam deposits are the two most widespread facies. The aeolian sand is characterized by horizontal alternating bedding, attributed to deposition of sand and silty sand on an alternating wet and dry surface. The loam is usually massive and interpreted as a reworked loess deposit. In the sediment sequence, a shift can be observed from a dominance of fluvial deposits to an alternation of fluvial and aeolian deposits and finally, to predominantly aeolian deposits. The majority of the sediments have been deposited during successive Middle‐ and Late‐Pleistocene glacial periods. It is argued that a high groundwater table, attributed to local subsidence and climatic conditions, was the main factor determining the local depositional environment and preservation potential of the sediments in the Roer Valley Graben. Copyright © 2004 John Wiley & Sons, Ltd.
Serum sex hormones and measures of benign prostatic hyperplasia
Authors: Roberts Rosebud O. , Jacobson Debra J. , Rhodes Thomas , Klee George G. , Leiber Michael M. , Jacobsen Steven J.
Published: April 2004

BACKGROUND

Despite biologic plausibility, the associations between sex hormones and measures of benign prostatic hyperplasia (BPH) have not been consistently reported.

METHODS

Subjects were randomly selected from the Olmsted County, MN population (n, 320; median age, 60.9 years) and followed biennially since 1990. In 2002, surrogate measures of BPH were assessed from an approximation of the American Urological Association Symptom Index (AUASI), Peak urinary flow rates (Qmax), and a transrectal ultrasound assessment of prostate volume. Serum levels of prostate specific antigen (PSA), testosterone, bioavailable testosterone, and estradiol were also measured.

RESULTS

Bioavailable testosterone levels declined with increasing cross‐sectional age from 53.8, 50.2, to 41.2 ng/dl (P = 0.001) in men aged <60, 60–69, and >69 years, respectively, and the estradiol/bioavailable testosterone ratio increased from 0.042, 0.044, to 0.050 (P = 0.04). Among men with bioavailable testosterone above the median, estradiol levels had a dose response relationship with prostate size. Among men with bioavailable testosterone level ≤ the median, however, there was no association between estradiol level and prostate volume

CONCLUSIONS

While cross‐sectional, these findings suggest a more complex relationship between sex steroids and prostate volume in older men than simple independent effects. © 2004 Wiley‐Liss, Inc.
Lysophosphatidic acid promotes survival of androgen‐insensitive prostate cancer PC3 cells via activation of NF‐κB
Authors: Raj Ganesh V. , Sekula Jeffrey A. , Guo Rishu , Madden John F. , Daaka Yehia
Published: April 2004

BACKGROUND

Dysregulated cell survival contributes to the poor efficacy of many chemotherapeutic regimens for patients with advanced prostate cancer. In this study we examined ability of the lipid growth factor lysophosphatidic acid (LPA), a G protein‐coupled receptor (GPCR) ligand, to promote prostate cell survival.

METHODS

PC3 cells were used as a model to study mechanisms involved in survival of androgen‐insensitive prostate cancer cells. Cell survival was measured by FACS analysis of cell cycle parameters after propidium iodide or annexin V and 7‐AAD immunostaining. Activation state of nuclear facor‐κB (NF‐κB) was determined biochemically by nuclear translocation and transcriptional activation. Human tissue was analyzed for nuclear expression of NF‐κB by immunohistochemistry.

RESULTS

Molecular dissection of the LPA‐regulated PC3 cell survival revealed the sequential phosphorylation of Akt, IκB, and transcriptional activation of NF‐κB. Both Akt and NF‐κB were required to escape serum deprivation‐induced cell death since their inhibition abrogated the LPA‐mediated PC3 cell survival. Data from archival human tissue show that NF‐κB is constitutively activated in prostate cancers, but not in benign prostate tissues.

CONCLUSIONS

Targeted disruption of the LPA receptor‐Akt–NF‐κB signaling axis may be effective for the treatment of androgen‐insensitive prostate cancer. © 2004 Wiley‐Liss, Inc.
Surgical margin and gleason score as predictors of postoperative recurrence in prostate cancer with or without chromosome 8p allelic imbalance
Authors: Zhou Wei , Goodman Michael , Lyles Robert H. , Lim So Dug , Williams Tanisha Y. , Rusthoven Kyle E. , Mandel Jack S. , Amin Mahul B. , Petros John A.
Published: April 2004

BACKGROUND

Identification of prostate cancer patients at risk for postoperative disease recurrence is an important clinical issue. Existing pathological markers can predict disease recurrence only to a certain extent, and there is a need for more accurate predictors.

METHODS

Using “counting alleles,” a novel experimental method, we determined allelic status of chromosome 8p in 107 prostatectomy specimens. Statistical analyses examined the association between pathologic predictors (Gleason score, stage, surgical margin, etc.) and cancer recurrence in patients with and without 8p allelic imbalance (8p AI).

RESULTS

8p AI cancers were more likely to recur in the presence of a positive surgical margin, whereas recurrence of 8p retaining tumors was associated with the Gleason score, but not with the surgical margin.

CONCLUSIONS

Our findings suggest that chromosome 8p allelic status affects the predictive value of “traditional” markers of prostate cancer recurrence. If confirmed by larger studies, these results may have important clinical implications. © 2004 Wiley‐Liss, Inc.
Effect of permixon on human prostate cell growth: Lack of apoptotic action
Authors: Hill Brian , Kyprianou Natasha
Published: April 2004

BACKGROUND

Permixon, a phytotherapeutic agent derived from the saw palmetto or Serenoa repens plant, is a lipid/sterol extract that is believed to interfere with 5α‐reductase activity, thus inhibiting prostate growth. In this study, we investigated the magnitude and specificity of the effect of Permixon on cell proliferation and apoptosis in human prostate cancer cells.

METHODS

The effect of Permixon was examined in androgen‐independent PC‐3 prostate cancer cells, androgen‐sensitive LNCaP prostate cancer cells, and MCF‐7 breast cancer cells in vitro. Cell growth, apoptosis induction, and cell proliferation was studied after exposure to Permixon at two concentrations (10 and 100 μg/ml). Cell proliferation and cell cycle progression were determined after 24 hr on the basis of 3[H]‐thymidine incorporation assay and flowcytometric analysis, respectively. Apoptosis induction was evaluated in treated and untreated cultures using the Hoescht staining and caspase‐3 activation.

RESULTS

Exposure of prostate and breast cancer cells to a high dose of Permixon (100 μg/ml) resulted in a significant decrease in the rate of cell growth; an effect that was not time‐dependent and was not associated with cell cycle arrest. Permixon treatment (at either high or low dose) had no effect on apoptosis induction in prostate cancer cell lines (P > 0.6). Furthermore, in vitro Permixon was a weak inhibitor of 5α‐reductase activity type 2 in prostatic homogenates.

CONCLUSIONS

The results indicate the ability of Permixon to affect prostate cancer cell growth without inducing apoptosis or cell cycle arrest. This effect was not prostate‐specific and was only manifested at high concentrations of Permixon. Furthermore our findings indicate that Permixon is weak inhibitor of 5α‐reductase compared to finasteride. This study challenges previous evidence on the anti‐growth effect of Permixon in the prostate and its ability to inhibit 5α‐reductase activity, while questioning apoptosis as a mechanism of action of this phytotherapeutic against prostate growth, a concept that may have therapeutic significance. © 2004 Wiley‐Liss, Inc.
Chemical potential induced phase transitions
Authors: Matlak M. , Molak A. , Pietruszka M.
Published: April 2004

A simple electrical set‐up to detect phase transitions is proposed and applied to a series of investigated samples: Gd, Cr, TiNi and CuZnSn, all exhibiting different types of phase transitions. The sample is glued to a contact electrode (here Ag) and immersed into a thermostat. We measure the electrical resistivity of the contact electrode as function of temperature. Due to the fact that the chemical potentials of the sample and the contact electrode should be equal (μs = μe) the electron gas of the contact electrode “feels” a phase transition taking place in the investigated sample. Therefore we observe kinks in the resistivity plot of the contact electrode which easily localize the proper critical temperatures: TC (Gd), TN (Cr) and Tstruct (TiNi, CuZnSn). The proposed method visualizes the prevailing role of the chemical potential at phase transitions and provides a completely new (“remote”) tool to detect critical points in solids. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The contributions of specific amino acid side chains to signal intensities of peptides in matrix‐assisted laser desorption/ionization mass spectrometry
Authors: Baumgart Sabine , Lindner Yvonne , Kühne Ronald , Oberemm Axel , Wenschuh Holger , Krause Eberhard
Published: April 2004

Matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐MS) analysis of complex peptide mixtures is often hampered by signal suppression effects as well as certain intrinsic properties of specific peptides that influence the desorption/ionization behavior. The present systematic study reports on the relationship between the occurrence of certain amino acids in peptides and the intensities of the related ions which appear during MALDI‐MS analysis for both tryptic digests of proteins and synthetic peptide mixtures. The analysis of the tryptic digests revealed that the peptide sequences of the most intense peaks detected by MALDI‐MS contained significantly higher proportions of arginine, phenylalanine, proline, and leucine than the average values for the measured proteins. The relationship between the relative signal intensities and amino acid compositions of peptides was studied in more detail by the partial least squares (PLS) method using equimolar mixtures of 144 well‐characterized synthetic peptides. The regression coefficients clearly indicated that the presence of arginine, phenylalanine, leucine and proline tend to enhance the desorption/ionization process which results in higher MALDI‐MS peak intensities. Furthermore, it was shown that the impact of arginine depends strongly on the identity of adjacent amino acids. Copyright © 2004 John Wiley & Sons, Ltd.
Atmospheric pressure matrix‐assisted laser desorption/ionization with analysis by ion mobility time‐of‐flight mass spectrometry
Authors: Steiner Wes E. , Clowers Brian H. , English William A. , Hill Herbert H.
Published: April 2004

The use of an atmospheric pressure matrix‐assisted laser desorption/ionization (AP‐MALDI) source was employed with an atmospheric pressure ion mobility spectrometer (APIMS) and an orthogonal acceleration reflector time‐of‐flight mass spectrometer (TOFMS) to analyze dipeptide and biogenic amine mixtures from a liquid glycerol 2,5‐dihydroxybenzoic acid (DHB) matrix. Improved sensitivities were obtained by the addition of a localized electrical (corona) discharge in conjunction with the AP‐MALDI source. Enhanced sample ionization efficiency created by this combination provided an overall elevation in signal intensity of ∼1.3 orders in magnitude. Combinations of three dipeptides (Gly‐Lys, Ala‐Lys, and Val‐Lys) and nine biogenic amines (dopamine, serotonin, B‐phenylethylamine, tyramine, octopamine, histamine, tryptamine, spermidine, and spermine) were resolved in less than 18 ms. In many cases, reduced mobility constants (Ko) were determined for these analytes for the first time. Ion mobility drift times, flight times, arbitrary signal intensities, and collision‐induced dissociation (CID) fragmentation product signatures are reported for each of the samples. Copyright © 2004 John Wiley & Sons, Ltd.
A mass spectrometry based method for distinguishing between symmetrically and asymmetrically dimethylated arginine residues
Authors: Brame Cynthia J. , Moran Michael F. , McBroom‐Cerajewski Linda D. B.
Published: April 2004

The arginine methylation of proteins is involved in several important cellular activities, most notably transcriptional control. Arginine dimethylation can take two distinct forms, symmetric and asymmetric, catalyzed by different classes of enzymes. To establish a method for the mass spectrometric identification and characterization of this post‐translational modification, we analyzed synthetic peptides with symmetrically or asymmetrically methylated arginine residues by electrospray ionization tandem mass spectrometry. We observed abundant characteristic ions at [M+nH–31]n+ and [M+nH–70]n+ in spectra of symmetrically methylated peptides and at [M+nH–45]n+ in spectra of asymmetrically methylated peptides. We speculate these ions arise from neutral loss of monomethylamine, dimethylcarbodiimide, and dimethylamine, respectively. These characteristic ions allowed the rapid identification of a symmetrically arginine‐dimethylated peptide from myelin basic protein and a symmetrically arginine‐dimethylated peptide from SmD3 co‐immunoprecipitated with the methyltransferase‐associated protein pICln, suggesting that this method may provide a rapid means to screen for and characterize dimethylarginine sites. Copyright © 2004 John Wiley & Sons, Ltd.
Effects of common surfactants on protein digestion and matrix‐assisted laser desorption/ionization mass spectrometric analysis of the digested peptides using two‐layer sample preparation
Authors: Zhang Nan , Li Liang
Published: April 2004

While surfactants are commonly used in preparing protein samples, their presence in a protein sample can potentially affect the enzymatic digestion process and the subsequent analysis of the resulting peptides by mass spectrometry. The extent of the tolerance of matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐MS) to surfactant interference in peptide analysis is very much dependent on the matrix/sample preparation method. In this work the effects of four commonly used surfactants, namely n‐octyl glucoside (OG), Triton X‐100 (TX‐100), 3‐[(3‐cholamidopropyl)dimethylammonio]‐1‐propanesulfonate (CHAPS) and sodium dodecyl sulfate (SDS), for biological sample preparation on trypsin digestion and MALDI‐MS of the resulting digest are examined in detail within the context of using a two‐layer method for MALDI matrix/sample preparation. Non‐ionic and mild surfactants, such as OG, TX‐100 or CHAPS, are found to have no significant effect on trypsin digestion with surfactant concentrations up to 1%. However, TX‐100 and CHAPS interfere with the subsequent peptide analysis by MALDI‐MS and should be removed prior to peptide analysis. OG is an MS‐friendly surfactant and no effect is observed for MALDI peptide analysis. The effect of SDS on trypsin digestion in terms of the number of peptides generated and the overall protein sequence coverage by these peptides is found to be protein dependent. The use of SDS to solubilize hydrophobic membrane proteins, followed by trypsin digestion in the presence of 0.1% SDS, results in a peptide mixture that can be analyzed directly by MALDI‐MS. These peptides are shown to provide better sequence coverage compared with those obtained without the use of SDS in the case of bacteriorhodopsin, a very hydrophobic transmembrane protein. This work illustrates that MALDI‐MS with the two‐layer sample preparation method can be used for direct analysis of protein digests with no or minimum sample cleanup after proteins are digested in a solution containing surfactants. Copyright © 2004 John Wiley & Sons, Ltd.
Qualität und Risiko: Auf diese Steine können Sie bauen…
Authors: Romeike Frank , Erben Roland Franz
Published: April 2004

Gutes Qualitätsmanagement senkt die Risiken, gutes Risikomanagement steigert die Qualität. Beide Ansätze haben mehr Gemeinsamkeiten, als man denkt. Die Vorgehensweise, sich beim Umgang mit Risiken allein auf das (in aller Regel bereits bestehende) Qualitätsmanagement zu verlassen, könnte sich allerdings als gefährlicher Trugschluss erweisen. Zwar besitzen viele der dort definierten Prozesse und Kennzahlen mit Sicherheit auch große Relevanz für das Risikomanagement, allerdings reflektieren diese in vielen Fällen nur einen relativ kleinen Teilausschnitt im Bereich der eigentlichen Leistungserstellung. Wesentliche Risiken, insbesondere solche strategischer Natur wie beispielsweise Reputationsrisiken, abrupte Technologiesprünge oder das Aufkommen neuer Wettbewerber lassen sich dadurch nicht erkennen. Ebenso wenig kann ein Qualitätsmanagementsystem die Bewertung und Steuerung derartiger Risikofaktoren leisten.
Was ist der „Value at Risk”︁?
Authors: von Balduin Alexander
Published: April 2004

Bei Investmentbankern hat die Kennzahl „Value at Risk”︁ (VaR) seit den 90er Jahren einen fast kultartigen Status erreicht. Inzwischen wird sie auch vermehrt in anderen Branchen und Risiko‐Bereichen angewandt. Übersetzt man „Value at Risk”︁ wörtlich, so erhält man den „gefährdeten Wert”︁. Doch was steckt hinter dieser Kennzahl? Inwieweit ist sie geeignet, Risiken korrekt zu bewerten?
Milchsumpf
Authors: Romeike Frank
Published: April 2004

Der italienische Konzern Parmalat beschäftigt rund 36.000 Menschen in 30 Ländern und erwirtschaftete im Jahr 2002 einen Umsatz von 7, 6 Milliarden Euro. Die Parmalat‐Aktie galt an der Mailänder Börse als grundsolide und sichere Geldanlage& allerdings nur bis zum 11. November 2003. An diesem Tag meldeten die Wirtschaftsprüfer erste Zweifel an der Bonität des Unternehmens an. Über einen Zeitraum von 15 Jahren hatte der Konzern seine Bilanz und Gewinn‐ und Verlustrechnung manipuliert und gefälscht und mit Mondzahlen operiert. Experten sprechen von einem der größten Finanzskandale in der europäischen Unternehmensgeschichte. Viele gehen davon aus, dass die Parmalat‐Pleite ähnlich verheerende Schockwellen auslösen wird wie der betrügerische Bankrott des US‐amerikanischen Energieriesen Enron im Dezember 2001. Die genaue Schadenshöhe ist bislang noch nicht abzusehen.
Auf Wiedersehen! Wenn der Kunde zurückkommt, nicht das Produkt. Interview mit Arndt G. Kirchhoff, Geschäftsführer der Kirchhoff‐Gruppe
Authors: Erben Roland F. , Romeike Frank
Published: April 2004

Die deutsche Automobilindustrie nimmt bei der Umsetzung von Qualitätsmanagement‐Systemen zweifellos eine Vorreiterrolle ein. Diese Anstrengungen haben natürlich auch erhebliche Konsequenzen für die vorgelagerten Stufen der Wertschöpfungskette. Zu den Herausforderungen, denen sich mittelständische Zulieferer heute gegenübersehen, befragten wir Arndt G. Kirchhoff, den Geschäftsführer der Kirchhoff‐Gruppe.
A consideration of e‐business modeling value evaluation
Authors: Takao Midori , Matsumoto Masao J.
Published: April 2004

Business is being reformed into e‐business via e‐business modeling. The value obtained by implementing e‐business is referred to as e‐business modeling value, and in this paper the authors discuss a framework for such an evaluation. Based on examples of changes in business value due to e‐business modeling in three industries, including consumer products manufacturing, the authors identify value targets for major business processes by closely investigating the differences between them and conventional business value evaluation targets. The authors offer their framework as one cause of the reduction in investor interest resulting from the currently weak frameworks to measure the effects of e‐business investment. © 2004 Wiley Periodicals, Inc. Syst Comp Jpn, 35(7): 85–97, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.10561
Geometry and learning curves of kernel methods with polynomial kernels
Authors: Ikeda Kazushi
Published: April 2004

The properties of learning machines with polynomial kernel classifiers, such as support vector machines or kernel perceptrons, are examined. We first derive the number of effective examples which are related to generalization error. Next, we analyze the average prediction errors of several algorithms and show these errors do not depend on the apparent dimension of the feature space. This means that what is called the overfitting phenomena do not appear in kernel methods with polynomial kernels. © 2004 Wiley Periodicals, Inc. Syst Comp Jpn, 35(7): 41–48, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.10629
Estimating high‐confidence portions based on agreement among outputs of multiple LVCSR models
Authors: Utsuro Takehito , Nishizaki Hiromitsu , Kodama Yasuhiro , Nakagawa Seiichi
Published: April 2004

This paper experimentally evaluates the agreement among the outputs of multiple Japanese LVCSR models, with respect to whether it is effective as an estimate of confidence for each hypothesized word. The results of experimental evaluation show that the agreement between the outputs with two LVCSR models with different decoders and acoustic models can achieve quite reliable confidence. Furthermore, among various features of acoustic models based on Gaussian mixture HMMs, it is concluded that ones such as whether or not to have short pause models, as well as different units in HMMs are the most effective in achieving highly reliable confidence. © 2004 Wiley Periodicals, Inc. Syst Comp Jpn, 35(7): 33–40, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.10636
Context‐aware agent platform in ubiquitous environments and its verification tests
Authors: Hattori Masanori , Cho Kenta , Ohsuga Akihiko , Isshiki Masao , Honiden Shinichi
Published: April 2004

This paper deals with the “ubiquitous personal agent,” which distinctively provides information services to the individual user depending on his/her personal contexts. This is made possible by recognition of user contexts in ubiquitous environments through an agent technology used to realize context‐aware intelligent environments.

This agent technology consists of a “context reasoning agent” and a “lightweight intelligent mobile agent.” The former is used for automatic recognition of various kinds of data and events which can be collected through realization of ubiquitous environments and of user “contexts.” The latter executes appropriate decentralization of a large variety of personalization‐related processing activities between various devices and server systems existing in the ubiquitous environments. In this paper, the details of the agent technology used are discussed and its effectiveness is confirmed by evaluation in tests of agent service using home information appliances already available on the domestic market. © 2004 Wiley Periodicals, Inc. Syst Comp Jpn, 35(7): 13–23, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.10655