bluuebunny/crossref_metadata_2025 huggingface dataset:
Multicut‐HDMR with an application to an ionospheric model
Authors: Li Genyuan , Schoendorf Jacqueline , Ho Tak‐San , Rabitz Herschel
Published: April 2004

A new High Dimensional Model Representation (HDMR) tool, Multicut‐HDMR, is introduced and applied to an ionospheric electron density model. HDMR is a general set of quantitative model assessment and analysis tools for improving the efficiency of deducing high‐dimensional input–output system behavior. HDMR describes an output [f(x)] in terms of its input variables (x = {x1, x2, …, xn}) via a series of finite, hierarchical, correlated function expansions. Various forms of HDMR are constructed for different purposes such as modeling laboratory or field data, or reproducing a complicated mathematical model. The Cut‐HDMR technique, which expresses f(x) with respect to a specified reference point x in the input space, is appropriate when the input space is sampled in an orderly fashion. However, if the desired domain of the input space is too large, the HDMR function expansion may not converge, and Cut‐HDMR will be unable to accurately approximate f(x). The new Multicut‐HDMR technique addresses this problem through the use of multiple reference points in the input space. © 2004 Wiley Periodicals, Inc. J Comput Chem 25: 1149–1156, 2004
Role of endoplasmic reticulum calcium content in prostate cancer cell growth regulation by IGF and TNFalpha
Authors: Humez Sandrine , Legrand Gillaume , Vanden‐Abeele Fabien , Monet Michaël , Marchetti Philipe , Lepage Gilbert , Crepin Alexandre , Dewailly Etienne , Wuytack Frank , Prevarskaya Natalia
Published: April 2004

Variations in calcium concentration within the endoplasmic reticulum ([Ca2+]ER) may play a role in cell growth. This study evaluates the regulation of calcium pools by growth modulators of prostate cancer (PC) cells, the insulin growth factor (IGF), and the tumor necrosis growth factor‐alpha (TNFalpha) as well as evaluating the possible role of [Ca2+]ER variations as signals for growth modulation. We show that IGF (5 ng/ml), which increases cell growth, induces an increase in [Ca2+]ER whereas TNFalpha (1 ng/ml) which reduces cell proliferation and induces apoptosis, reduces [Ca2+]ER. IGF‐induced [Ca2+]ER increase is correlated to an overexpression of the sarcoendoplasmic calcium‐ATPase 2B (SERCA2b), whereas TNFalpha‐induced [Ca2+]ER decrease is associated to a reduction in SERCA2b expression. Pretreatment with epidermal growth factors (EGF) or IGF does not prevent TNFalpha from affecting the induction of apoptosis, [Ca2+]ER reduction and SERCA2b downregulation. Reduction in [Ca2+]ER induced by thapsigargin (TG) (from 1 pM to 1 μM, 48 h) reduces LNCaP growth in a dose dependent manner and induces apoptosis when cells are treated with 1 μM TG. We also show that a transient TG application (1 pM, 1 nM, 1 μM 15 min) is insufficient to induce a long lasting decrease in [Ca2+]ER, since [Ca2+]ER remains identical to the control for 48 h following TG application. These treatments (1 pM and 1 nM, 15 min) do not modify cell growth. However, TG (1 μM, 15 min) induces apoptosis. We thus identify [Ca2+]ER and SERCA2b as a central targets for causing LNCaP PC cell life or death induced by growth modulators. Furthermore our results indicate that calcium pool contents can regulate cell growth. © 2004 Wiley‐Liss, Inc.
Activity and expression of Xenopus laevis matrix metalloproteinases: Identification of a novel role for the hormone prolactin in regulating collagenolysis in both amphibians and mammals
Authors: Jung Jae‐Chang , West‐Mays Judith A. , Stramer Brian M. , Byrne Michael H. , Scott Sumi , Mody Mehernosh K. , Sadow Peter M. , Krane Stephen M. , Fini M. Elizabeth
Published: April 2004

Prolactin (PRL) has long been implicated in Xenopus metamorphosis as an anti‐metamorphic and/or juvenilizing hormone. Numerous studies showed that PRL could prevent effects of either endogenous or exogenous thyroid hormone (TH; T3). It has been shown that expression of matrix metalloproteinases (MMPs) is induced by TH during Xenopus metamorphosis. Direct in vivo evidence, however, for such anti‐TH effects by PRL with respect to MMPs has not been available for the early phase of Xenopus development or metamorphosis. To understand the functional role of PRL, we investigated effects of PRL on Xenopus collagenase‐3 (XCL3) and collagenase‐4 (XCL4) expression in a cultured Xenopus laevis cell line, XL‐177. Northern blot analysis demonstrated that XCL3 and XCL4 expression were not detected in control or T3‐treated cells, but were differentially induced by PRL in a dose‐ and time‐dependent fashion. Moreover, treatment with IL‐1α as well as phorbol myristate acetate (PMA), a protein kinase C (PKC) activator, or H8, a protein kinase A (PKA) inhibitor, augmented PRL‐induced collagenase expression, suggesting that multiple protein kinase pathways and cytokines may participate in PRL‐induced collagenase expression. Interestingly, XCL3 expression could be induced in XL‐177 cells by T3, but only when co‐cultured with prometamorphic Xenopus tadpole tails (stage 54/55), suggesting that the tails secrete a required intermediate signaling molecule(s) for T3‐induced XCL3 expression. Taken together, these data demonstrate that XCL3 and XCL4 can be differentially induced by PRL and T3 and further suggest that PRL is a candidate regulator of TH‐independent collagenase expression during the organ/tissue remodeling which occurs in Xenopus development. J. Cell. Physiol. 201: 165, 2004. © 2004 Wiley‐Liss, Inc.
Chiral Polymers Containing a Carbohydrate Moiety: Synthesis
Authors: Maślińska‐Solich Jolanta , Kukowka Sylwia
Published: April 2004

Summary: This paper reports the preparation of poly(acetal‐ethers) by two alternative synthetic pathways (alkaline and acid‐catalyzed conditions). Polycondensations of methyl 2,3:4,6‐di‐O‐salicylidene‐α‐D‐mannopyranoside (3) (mixtures of endo‐H and exo‐H dioxolan‐2‐yl‐diastereomers) with 1,4‐dibromobutane (4) (method I a and I b) were performed in solvents (DMF, butyl acetate/DMF, DMSO) and were catalyzed by K2CO3/KI or KOH. A similar polymer (6) was formed by the reaction of methyl α‐D‐mannopyranoside (1) and 1,4‐bis(2‐formylphenoxy)butane (7), catalyzed by p‐toluenesulfonic acid (method II). Regardless of conversion or initial comonomer feed ratios, the composition of the polycondensates depended on the reaction conditions, leading to the formation of macrocyclic [1 + 1] (5) and [2 + 2] compounds, which were macromolecules with diverse molecular weights and optical properties. The regioselective polycondensation was examined by 1H NMR spectroscopy of selected polymers. In the case of 5‐membered cyclic acetal units, mixtures of the endo‐H and exo‐H dioxolan‐2‐yl system, diastereomers were formed in the polymer chain. The macrocycles and linear oligomers were identified by NMR and electrospray mass spectrometry (ESI‐MS). Thermodynamically controlled reactions for making macrocycles as well as oligomers in the absence of templates are also discussed.

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Amphiphilic Block Copolymers Based on Poly(2‐acryloyloxyethyl phosphorylcholine) Prepared via RAFT Polymerisation as Biocompatible Nanocontainers
Authors: Stenzel Martina H. , Barner‐Kowollik Christopher , Davis Thomas P. , Dalton Helen M.
Published: April 2004

Summary: Amphiphilic block copolymers composed of poly(butyl acrylate) and poly(2‐acryloyloxyethyl phosphorylcholine) have been prepared using reversible addition fragmentation transfer (RAFT) polymerisation. The conversion of the polymerisation was determined using online FT NIR spectroscopy. NMR spectroscopy was used not only to support the results obtained from FT NIR spectroscopy but also prove the formation of micelles. Due to the strong aggregation tendency of these block copolymers and the resulting difficulties concerning the molecular weight analysis test experiments were carried out replacing poly(2‐acryloyloxyethyl phosphorylcholine) with poly(2‐hydroxyethyl acrylate). Micelle size and the aggregation behaviour were investigated using dynamic light scattering. The sizes of the nanocontainers obtained were found to be influenced by the block length as well as the solvent leading to micelles in the range between 40 and 160 nm. The toxicity of the RAFT agent used was then analysed by cell growth inhibition tests.

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Cover Picture: Macromol. Biosci. 4/2004
Authors: Maślińska‐Solich Jolanta , Kukowka Sylwia
Published: April 2004

Cover: A convenient preparation for a new type of macrocyclic and linear oligomers with carbohydrate moiety (methyl α‐D‐mannopyranoside and salicylaldehyde derivatives) is reported. The thermodynamically controlled reaction to make macrocycles as well as linear oligomers in the absence of template becomes a valuable addition to the limited number of reaction types using dynamic covalent chemistry.

Further details can be found in the Full Paper by J. Maślińsska‐Solich* and S. Kukowka on page 421.
Cocrystallization of Blends of Ethylene/1‐Olefin Copolymers: An Investigation with Crystallization Analysis Fractionation (Crystaf)
Authors: Anantawaraskul Siripon , Soares João B. P. , Wood‐Adams Paula M.
Published: April 2004

Summary: Crystallization analysis fractionation (Crystaf) is a technique for estimating the chemical composition distribution (CCD) of semi‐crystalline copolymers. Cocrystallization may happen during Crystaf analysis, affecting Crystaf profiles and leading to misinterpretation of the CCD. This study investigates this phenomenon and determines the main factors leading to cocrystallization by analyzing a series of ethylene/1‐olefin copolymers. We considered three factors affecting cocrystallization: comonomer type, cooling rate and chain crystallizability. The results showed that cooling rate and similarity in chain crystallizability are the key factors regulating cocrystallization during Crystaf analysis.

Crystaf analysis of blends of copolymers.

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Crystaf analysis of blends of copolymers.
Pregnancy in stiff‐limb syndrome
Authors: Weatherby Stuart J.M. , Woolner Philippa , Clarke Carl E.
Published: April 2004

To our knowledge, pregnancy in a patient with stiff‐limb‐syndrome (SLS) has not been reported. We present the case of a woman with SLS who improved during pregnancy, delivered a normal healthy baby by forceps‐assisted vaginal delivery, and suffered a mild postpartum “relapse.” © 2004 Movement Disorder Society
Indirect nuclear spin–spin coupling constants in 1,2‐diboretane‐3‐ylidene, a homoaromatic system with π and σ 3c/2e bonds. Comparison of experimental data with calculations using density functional theory (DFT)
Authors: Wrackmeyer Bernd , Berndt Armin
Published: April 2004

The non‐classical 1,2‐diboretane‐3‐ylidene 1a was studied by 13C and 29Si NMR spectroscopy in order to obtain coupling constants 1J(13C,11B) and 1J(29Si,13C). The magnitudes of 1J(13C,11B) were deduced from linewidth measurements in low‐temperature 13C and 11B NMR spectra. Calculation of the coupling constants for model compounds related to 1a, using DFT methods based on optimized geometries [B3LYP/6–311+G(d,p)], gave data in agreement with the experiments. Furthermore, the calculations predict for the first time a negative sign of 1J(13C,11B) which mirrors the bonding situation in 1 as described by theory. Copyright © 2004 John Wiley & Sons, Ltd.
Investigations of intramolecular hydrogen bonding in three types of Schiff bases by 2H and 3H NMR isotope effects
Authors: Schilf Wojciech , Bloxsidge James P. , Jones John R. , Lu Shui‐Yu
Published: April 2004

Hydrogen bonding within the structures of three Schiff bases (1–3), obtained by condensation of 4‐methoxy‐, 5‐methoxy‐ and 4,6‐dimethoxysalicylaldehyde with methylamine, was investigated by measuring deuterium and tritium NMR isotope effects. The primary deuterium and tritium isotope effects (δXH−δXD/T) and secondary one‐bond nitrogen deuterium effect appear to be very useful parameters for defining the character of intramolecular hydrogen bonds. The tritium isotope effects were also determined for nitrogen–hydrogen one‐bond coupling constants for both 4‐methoxy and 4,6‐dimethoxy derivatives. These parameters are seen to be highly sensitive to hydrogen bond characteristics and can be used to distinguish localized and tautomeric hydrogen bonds. Copyright © 2004 John Wiley & Sons, Ltd.
Chromatin organization during spermiogenesis in Octopus vulgaris. II: DNA‐interacting proteins
Authors: Giménez‐Bonafé Pepita , Soler Fina Martínez , Buesa Carlos , Sautière Pierre‐Eric , Ausió Juan , Kouach Mostafa , Kasinsky Harold E. , Chiva Manel
Published: April 2004

In this article we study the proteins responsible for chromatin condensation during spermiogenesis in the cephalopod Octopus vulgaris. The DNA of ripe sperm nuclei in this species is condensed by a set of five different proteins. Four of these proteins are protamines. The main protamine (Po2), a protein of 44 amino acid residues, is extraordinarily simple (composed of only three different amino acid types: arginine (R), serine (S), and glycine (G). It is a basic molecule consisting of 79.5 mol% arginine residues. The rest of the protamines (Po3, Po4, Po5) are smaller molecules (33, 28, and 30 amino acid residues, respectively) that are homologous among themselves and probably with the main Po2 protamine. The ripe sperm nucleus of O. vulgaris also contains a small quantity of a molecule (Po1) that is similar to Po2 protamine. This protein could represent a Po2 protamine‐precursor in a very advanced step of its processing. We discuss the characteristics of these proteins, as well as the relation between the complexity of chromatin condensation and the transitions of nuclear proteins during spermiogenesis in O. vulgaris. Mol. Reprod. Dev. 68: 232–239, 2004. © 2004 Wiley‐Liss, Inc.
Development, chromosomal composition, and cell allocation of bovine cloned blastocyst derived from chemically assisted enucleation and cultured in conditioned media
Authors: Li Guang‐Peng , Bunch Thomas D. , White Kenneth L. , Aston Kenneth I. , Meerdo Lora N. , Pate Barry J. , Sessions Benjamin R.
Published: April 2004

Treatment of in vitro matured bovine oocytes with colcemid results in a membrane protrusion that contains maternal chromosomes, which can be easily removed by aspiration. Four experiments were designed to evaluate the overall and temporal effects of conditioned medium (CM) by bovine cumulus cells on development of nuclear transfer (NT) bovine embryos and to examine the chromosomal composition and allocation of inner cell mass (ICM) and trophectoderm (TE) of the subsequent blastocysts. The nuclear transfer embryos were cultured in various CR1aa media conditioned by preculture with bovine cumulus cells. Development to the blastocyst stage in BSA‐containing CM (BCM) and serum‐containing CM (SCM) were similar to co‐culture group (24–30%). The 24 hr‐conditioned BCM yielded higher blastocyst development than 48 and 72 hr‐conditioned BCM. Temporary exposure of embryos to BCM and SCM followed by CR1aa was also studied. Morula and blastocyst development were not different among the groups cultured in BCM for 72, 96, and 168 hr, but were significantly higher (P < 0.01) than groups exposed to BCM for 24 and 48 hr, respectively. Blastocyst development in SCM for 24 hr (29%), 96 hr (25%), and 168 hr (27%) were much higher (P < 0.05) than those in SCM for 48 hr (12%) and 72 hr (10%). The analyses of chromosomal composition of the resulting blastocysts indicate approximately 80% of the blastocysts cultured in CR1aa with co‐culture or groups initially exposed to BCM for 24 hr followed by culture in CR1aa were diploid. However, the incidence of diploidy were only 36–60% in SCM‐cultured groups and groups cultured in BCM beyond 48 hr. Conditioned media did not affect the allocation of ICM and TE in the blastocyst. No difference was found in the ratio of inner cell mass to total cells in co‐culture, BCM or SCM groups (0.424, 0.441, and 0.473, respectively). In conclusion, bovine cumulus cell‐CM and CR1aa with co‐culture supported comparable development and blastocyst ICM:total cell ratio of bovine NT embryos. However, CM affected the blastocyst chromosomal composition and induced higher mixploidy. Mol. Reprod. Dev. 68: 189–197, 2004. © 2004 Wiley‐Liss, Inc.
Expression of PTEN in malignant and non‐malignant human prostate tissues: comparison with p27 protein expression
Authors: Fenic Irina , Franke Folker , Failing Klaus , Steger Klaus , Woenckhaus Joachim
Published: April 2004

The role of the putative tumour suppressor PTEN in prostate carcinogenesis is controversial. There are conflicting data regarding the rate of its gene inactivation, the role of transcriptional and post‐transcriptional factors, as well as its relationship to tumour progression and to the potential downstream regulator, the cell‐cycle inhibitor p27. The present study has assessed the in situ expression of PTEN mRNA and protein in 26 prostate intraepithelial neoplasias (PINs), 58 primary prostate carcinomas, and 15 metastases. Although there was a correlation between PTEN mRNA and protein expression, mRNA detection exceeded detection of protein in 19% of PINs and 30% of all invasive tumours. Using RT‐PCR and western blotting on microdissected tissue, this discrepancy was attributed, at least in part, to transcription of the PTEN pseudo‐gene, which lacks introns. Total or partial loss of PTEN protein occurred with tumour progression but this association was not statistically significant. Analysing the relationship between PTEN and p27 protein expression on consecutive sections by immunohistochemistry, the results do not support a direct link between the two oncosuppressors, other than an associated loss of expression in advanced tumour stages. However, in the basal cells of prostate glands and in most PINs, an inverse relationship was observed between PTEN and p27. This may reflect the existence of a functional balance that controls the cell cycle in prostatic epithelium and that is probably disturbed in invasive tumour cells. Copyright © 2004 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Heparanase expression during normal liver development and following partial hepatectomy
Authors: Goldshmidt Orit , Yeikilis Rita , Mawasi Nidal , Paizi Melia , Gan Noga , Ilan Neta , Pappo Orit , Vlodavsky Israel , Spira Gadi
Published: April 2004

Heparan sulphate proteoglycans are major components of the liver extracellular matrix. Their cleavage by heparanase (endo‐β‐glucuronidase) may thus be involved in liver‐specific normal and pathological processes. Heparanase mRNA and protein were expressed during liver development but not in the mature healthy liver. A biphasic gain of heparanase expression, detected by immunostaining, western blotting, and real‐time RT‐PCR, was clearly noted following partial hepatectomy, peaking at 12 and 96–168 h and subsiding 2 weeks post‐surgery. Expression of heparan sulphate gradually increased throughout the regeneration process. Unlike heparanase, baseline levels of matrix metalloproteinase‐2 (MMP‐2) were detected in the intact liver, increasing up to 4 days following partial hepatectomy and subsiding at day 10. Bands matching MMP‐9 were absent prior to hepatectomy, but visible 2 h post‐hepatectomy. Thioacetamide‐induced liver fibrosis was associated with increased levels of MMP‐9 and MMP‐2, correlating with the severity of the disease. Elevated heparanase levels were noted in the early stages of fibrosis, with no further increase evident in rats exhibiting higher fibrotic grades. Taken together, these data suggest a role for heparanase during liver development and remodelling. Copyright © 2004 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Comprehensive study of polymer fiber surface modifications Part 2: low‐temperature oxygen‐plasma treatment
Authors: Yip Joanne , Chan Kwong , Sin Kwan Moon , Lau Kai Shui
Published: April 2004

Polyamide fibers were treated with a low‐temperature oxygen plasma and the effects on the morphology, chemistry and crystallinity of the material were studied. Topographical results illustrate that changes in the surface morphology of the oxygen‐plasma‐treated polyamide correlate well with the discharge power and treatment time. The effects can be categorized into three groups: surface cleaning resulting in a smoother surface, surface etching with formation of ‘ripple‐like’ structures of sub‐micrometer size, and surface melting with down grading of the material. Chemical studies show that the surface oxygen content of the polyamide increases after oxygen‐plasma treatment. The latter induces the formation of many hydroxyl and carboxylic acid functional groups. These groups mainly replace the hydrocarbon or carbonyl groups in the polyamide. Differential scanning calorimetry (DSC) results indicate that a short treatment time does not affect the degree of crystallinity of the polyamide material, while a long plasma‐treatment time slightly increases the crystallized fraction. Copyright © 2004 Society of Chemical Industry
Chemorheological studies on a dicyanate resin modified with polyethersulfone
Authors: Hong Bong Taek , Roh Seung Sang , Kim Dae Su
Published: April 2004

The chemorheology of a dicyanate resin modified with a polyethersulfone (PES) was investigated. The rheological and dielectrical property changes during curing of the dicyanate resin system catalyzed by an organic metal salt were monitored by a rheometer and dielectric analyzer, respectively, and used to investigate the curing behavior and chemorheology of the resin system. The curing rate of the dicyanate resin system decreased as the PES content was increased. A function that can describe the viscosity change of the dicyanate resin system during curing was determined by a nonlinear regression method using the rheometer data. The gelation time of the dicyanate resin system decreased with increasing isothermal curing temperature and with decreasing PES content. The curing behavior of the dicyanate resin system monitored by the dielectric analyzer coincided fairly well with that measured by the rheometer Copyright © 2004 Society of Chemical Industry
Athermal simulation of plastic deformation in amorphous solids at constant pressure
Authors: Utz Marcel , Peng Qing , Nandagopal Magesh
Published: April 2004

An algorithm is introduced for the molecular simulation of constant‐pressure plastic deformation in amorphous solids at zero temperature. This allows to directly study the volume changes associated with plastic deformation (dilatancy) in glassy solids. In particular, the dilatancy of polymer glasses is an important aspect of their mechanical behavior. The new method is closely related to Berendsen's barostat, which is widely used for molecular dynamics simulations at constant pressure. The new algorithm is applied to plane strain compression of a binary Lennard‐Jones glass. Conditions of constant volume lead to an increase of pressure with strain, and to a concommitant increase in shear stress. At constant (zero) pressure, by contrast, the shear stress remains constant up to the largest strains investigated (ε = 1), while the system density decreases linearly with strain. The linearity of this decrease suggests that each elementary shear relaxation event brings about an increase in volume which is proportional to the amount of shear. In contrast to the stress–strain behavior, the strain‐induced structural relaxation, as measured by the self‐part of the intermediate structure factor, was found to be the same in both cases. This suggests that the energy barriers that must be overcome for their nucleation continually grow in the case of constant‐volume deformation, but remain the same if the deformation is carried out at constant pressure. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2057–2065, 2004
Relict sorted patterned ground in Lesotho
Authors: Sumner Paul
Published: April 2004

Relict sorted patterned ground is described from an upland interfluve on the Lesotho‐South Africa border at an elevation of 3280 m a.s.l. The site comprises 2–4° slope angles. Frost penetration through the regolith is inferred to have been to 1 m depth during pattern formation. Sorting is thought to have resulted from deep seasonal freezing during the depressed temperatures of the Late‐Pleistocene Last Glacial Maximum (∼18 000 years B.P.). No direct evidence for permafrost is documented. Copyright © 2004 John Wiley & Sons, Ltd.
A field perspective on modelling ‘single‐ridge’ ice‐wedge polygons
Authors: Burn C. R.
Published: April 2004

Plug and Werner (Nature 2002, vol. 417, pp. 929–933) have constructed a model for the growth of ice‐wedge polygons. Contrary to field evidence, the model describes development of ice wedges in frozen ground beneath a centre line of ridges and assumes that effects associated with perturbations in the thermal stress field due to growth of individual wedges may dissipate in the long run. In the field, troughs, not ridges, overlie wedges, and development of the troughs as the ice wedges grow increases snow accumulation above the wedges, so that older wedges may crack less frequently than younger ice wedges. As a result, the ‘single‐ridge’ model does not replicate the inexorable evolution of polygonal networks in the field, because the underlying assumptions are inconsistent with field conditions. Instead, the ‘single‐ridge’ ice‐wedge model attributes network development only to periods of high thermal stress, i.e. particularly cold winters. The model has been used to simulate development of such networks ab initio, by considering conditions in a recently drained thaw lake. However, the results do not reproduce field conditions because the model operates in frozen, not freezing ground, and therefore the initial modelled network is greatly exaggerated from known field observations. While the conclusions of the modelling are presented in general terms, the model only considers epigenetic polygons, which comprise a small fraction of the ice‐wedge polygons in polar terrain. Other, more extensive, syngenetic and anti‐syngenetic (hillslope) polygon networks are not mentioned. Copyright © 2004 John Wiley & Sons, Ltd.
The thermal environment of blocky materials in the mountains of Central Asia
Authors: Gorbunov Aldar P. , Marchenko Sergei S. , Seversky Eduard V.
Published: April 2004

Geothermal investigations in the Transili Alatau Range (Northern Tien Shan) during 1974–87 reveal a significant difference between the thermal regime of coarse blocky materials and adjacent fine‐grained soils. Mean annual temperatures inside the coarse debris are 2.5–4.0°C cooler than mean annual air temperatures (MAATs). In such conditions, permafrost may develop within coarse debris even under a positive mean annual air temperature. In the Transili Alatau Range, the process of perennially freezing is possible at altitudes of 1800–1900 m ASL where the MAA T is about 4°C. Copyright © 2004 John Wiley & Sons, Ltd.
Probability mapping of mountain permafrost using the BTS method, Wolf Creek, Yukon Territory, Canada
Authors: Lewkowicz Antoni G. , Ednie Mark
Published: April 2004

The basal temperature of snow (BTS) method was used to predict the distribution of permafrost within a mountainous basin located in the southern Yukon Territory. A modelled BTS surface, based on several hundred measured values, was created within a Geographic Information System (GIS) environment using elevation and potential incoming solar radiation as independent variables. The distribution of frozen ground at 200 test sites was compared to the modelled BTS values using logistic regression. The resultant map of permafrost probability shows that all four conventional permafrost distribution classes (isolated patches, scattered and widespread discontinuous permafrost, and continuous permafrost) are present within the basin. Supplementary logistic regression analyses reveal that at certain elevations and aspects, the probability of permafrost occurrence varies markedly over short distances in response to snowpack depth. They also show that widespread alterations in snow cover would be expected to substantially affect permafrost distribution even if air temperatures were to remain unchanged. Copyright © 2004 John Wiley & Sons, Ltd.
Nitrosulindac (NCX 1102): A new nitric oxide‐donating non‐steroidal anti‐inflammatory drug (NO‐NSAID), inhibits proliferation and induces apoptosis in human prostatic epithelial cell lines
Authors: Huguenin Sandra , Fleury‐Feith Jocelyne , Kheuang Laurence , Jaurand Marie‐Claude , Bolla Manlio , Riffaud Jean‐Pierre , Chopin Dominique K. , Vacherot Francis
Published: April 2004

BACKGROUND

The aim of our study was to explore the anti‐tumoral potential of the Nitric Oxide‐Donating Non‐Steroidal Anti‐Inflammatory Drugs (NO‐NSAID) NCX1102 (nitrosulindac), on three human prostatic epithelial cell lines at varying degree of transformation (PNT1A, LNCaP, and PC3).

METHODS

Cytotoxicity, anti‐proliferative effects, cell‐cycle alterations, morphological changes, and apoptosis were investigated after treatment with nitrosulindac in comparison to the native molecule sulindac. Involvement of the polyamine pathway in the action of nitrosulindac was also examined.

RESULTS

Nitrosulindac but not sulindac exerted a cytotoxic effect on all cell lines and an anti‐proliferative effect on LNCaP and PC3 cells only. Nitrosulindac differentially altered the cell cycle, induced mitotic arrest and displayed a pro‐apoptotic activity in all cell lines. Finally, the polyamine pathway does not seem to be involved in the mechanism of nitrosulindac action.

CONCLUSIONS

Our results demonstrate the anti‐proliferative and proapoptotic activity of nitrosulindac on prostate cancer cell lines and suggest its potential interest for new strategies in the management of prostate cancer. © 2004 Wiley‐Liss, Inc.
Prosaptide TX14A stimulates growth, migration, and invasion and activates the Raf‐MEK‐ERK‐RSK‐Elk‐1 signaling pathway in prostate cancer cells
Authors: Koochekpour Shahriar , Sartor Oliver , Lee Tae‐Jin , Zieske Arthur , Patten David Y. , Hiraiwa Masao , Sandhoff Konrad , Remmel Natascha , Minokadeh Ardalan
Published: April 2004

BACKGROUND

Prosaposin is a neurotrophic factor. Prosaposin knock‐out mice have been reported to develop a number of abnormalities, including atrophy of the prostate gland and mitogen‐activated protein kinase (MAPK)‐inactivation in prostate epithelial cells. These abnormalities underscore a potential fundamental role in prostate development. The trophic factor activity of prosaposin has been localized at a specific amino terminal portion of the molecule that has been the source for a number of biologically active peptides called prosaptides (e.g., TX14A). The expression and function of prosaposin in prostate cancer is not known.

METHODS

Using conventional protein expression analysis, immunohistochemical staining, cell proliferation assays, and in vitro invasion assays, we determined the expression of prosaposin and the effect of prosaptide TX14A on cell growth/death protection, motility, invasion, and MAPK signal transduction pathway in prostate cancer cells.

RESULTS

We found a higher expression of prosaposin in androgen‐independent (AI) prostate cancer cells (PC‐3 and DU‐145) than in androgen‐dependent (AD) LNCaP or normal prostate epithelial cells. Immunohistochemical staining on benign and malignant prostate tissues revealed an intense cytoplasmic anti‐prosaposin immunoreactivity in tumor cells, as well as stromal, endothelial, and inflammatory mononuclear cells. The intensity of staining was proportional to the overall Gleason's score. In addition, we demonstrated that TX14A stimulates cell proliferation/survival, migration, and invasion, and activates the Raf‐MEK‐ERK‐RSK‐Elk‐1 signaling cascade of the MAPK pathway.

CONCLUSIONS

These results are suggestive of a potential pleuripotent regulatory function for prosaposin in prostate cancer. © 2004 Wiley‐Liss, Inc.
Integrated modeling environment for statewide assessment of groundwater vulnerability from pesticide use in agriculture
Authors: Eason Audra , Tim U Sunday , Wang Xixi
Published: April 2004

Atrazine, a herbicide widely used for corn production in the Midwest, has been detected in groundwater of several states, and has been identified as a possible human carcinogen. With the widespread use of pesticides in crop production, and the frequent detection of these chemicals in groundwater, large‐scale risk assessments would help water resource managers to identify areas that are more susceptible to contamination and implement practices to ameliorate the problem. This paper presents an integrated, visual and interactive system for predicting potential environmental risks associated with pesticide contamination at spatial scales ranging from fields to landscapes and regions. The interactive system extends the predictive ability of the Pesticide Root Zone Model Release 2.0 (PRZM‐2) to a landscape and statewide scale through integration with a geographic information system (GIS), graphical user interface and environmental databases. Predictions of statewide (Iowa) vulnerability of groundwater from atrazine leaching below the unsaturated zone were made to demonstrate the utility of the system, and the results were used in risk assessment. In the example application, atrazine fate and transport were evaluated using long‐term climatic data (1980–1989) in combination with several environmental databases (eg STATSGO soils database) and exposure risks were expressed in terms of the probability of the predicted pesticide concentrations exceeding the maximum contaminant level (MCL) for drinking water. The results indicate that the predicted pesticide concentrations were significantly lower than the EPA‐established MCL. In addition to providing an interactive environment for landscape‐level assessment of potential risks from pesticide leaching, the system significantly reduces the time and resources needed to organize and manipulate data for use with PRZM‐2, and provides an analytical framework for evaluating groundwater‐leaching impacts of pesticide management practices. Copyright © 2004 Society of Chemical Industry
Monitoring and characterization of Magnaporthe grisea isolates with decreased sensitivity to scytalone dehydratase inhibitors
Authors: Sawada Haruko , Sugihara Minoru , Takagaki Makiichi , Nagayama Kozo
Published: April 2004

Rice blast fungus isolates were collected in Kyushu to investigate resistance to scytalone dehydratase inhibitors of melanin biosynthesis (MBI‐D). In 2001, failure of control of rice blast was reported in the Saga prefecture, where MBI‐Ds have been used since 1998. At that time, the distribution of resistant isolates was mainly limited to that area. However, in 2002, resistant isolates were detected in all prefectures of Kyushu. DNA fingerprinting analysis showed that the mutation causing resistance to MBI‐Ds had arisen independently in each area. These data suggest that resistant isolates may occur in any area and become dominant under continuous selection pressure for MBI‐Ds. Nevertheless, resistant strains can be controlled by reductase inhibitors of melanin biosynthesis (MBI‐R) or commercial rice seed disinfectants. Copyright © 2004 Society of Chemical Industry
Femtomol sensitivity post‐digest 18O labeling for relative quantification of differential protein complex composition
Authors: Bantscheff Marcus , Dümpelfeld Birgit , Kuster Bernhard
Published: April 2004

Stable isotope labeling (SIL) has emerged as a powerful tool to measure the relative quantitative differences between samples in many differential display‐type proteomic applications. However, current SIL procedures tend to suffer from the fact that one needs to decide very early in a biochemical strategy whether or not a sample will be subjected to relative quantification. Typically, the entire strategy has to be adapted to the needs of the particular quantification method chosen which might limit the range of biochemical experiments amenable to quantification. Metabolic labeling approaches, albeit very sensitive, can only be applied to studies using appropriate cell culture systems which might not necessarily be compatible with the biological system under investigation. Chemical labeling of complex protein mixtures by, e.g., isotope‐coded affinity tags (ICAT), can offer great simplification of protein mixtures but is restricted by the accessibility of the often few suitable peptides (i.e. cysteine containing peptides) for both protein identification and quantification. Here, we describe a post‐digest 18O‐labeling method that can circumvent some of the above limitations by separating protein identification from quantification. An aliquot of all samples in a set can be used for rapid protein ID using, e.g., matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOFMS). In a second step, relative quantification is performed using trypsin‐catalyzed 18O incorporation into all tryptic peptides. This two‐stage procedure introduces significant experimental flexibility because it enables postponement of the decision about which pairs of samples from a given set of experiments are to be compared until after the protein ID stage. In‐gel digested protein quantities between 50 fmol and 15 pmol are amenable to this new method, with a dynamic range of 1:10 within one sample. Accuracy for measured relative abundances is similar to those reported for other SIL strategies (errors typically <20%), and the method is applicable to protein samples from all kinds of tissue or cell culture. This paper presents quantification data for a set of standard proteins, as well as a study of differential complex formation around the NFκB transcription factor p65 following stimulation with TNF‐α. Copyright © 2004 John Wiley & Sons, Ltd.
Sequit: software for de novo peptide sequencing by matrix‐assisted laser desorption/ionization post‐source decay mass spectrometry
Authors: Demine Rodion , Walden Peter
Published: April 2004

Peptide sequencing by mass spectrometry is gaining increasing importance for peptide chemistry and proteomics. However, available tools for interpreting matrix‐assisted laser desorption/ionization post‐source decay (MALDI‐PSD) mass spectra depend on databases, and identify peptides by matching experimental data with spectra calculated from database sequences. This severely obstructs the identification of proteins and peptides not listed in databases or of variations, e.g. mutated proteins. The development of a new computer program for database‐independent peptide sequencing by MALDI‐PSD mass spectrometry is reported here. This computer program was validated by the determination of the correct sequences for various peptides including sequences listed in the sequence databases, but also for peptides that deviate from database sequences or are completely artificial. This strategy should substantially facilitate the identification of novel or variant peptides and proteins, and increase the power of MALDI‐PSD analyses in proteomics. Copyright © 2004 John Wiley & Sons, Ltd.
Risiko und Qualität: Die zwei Seiten einer Medaille?
Authors: Meier Peter
Published: April 2004

Im Rahmen einer Systembetrachtung werden Risiko und Qualität zusammen definiert. Sie ergeben sich aus einem definierten SOLL‐Wert und einem beobachteten IST‐Wert der entsprechenden Kriterien. Risiko ist die absolute Differenz zwischen SOLL und IST, skaliert um die Wahrscheinlichkeit dieser Differenz. Qualität ist das relative Verhältnis von IST und SOLL. Diese Definitionen sind kompatibel mit dem üblichen Gebrauch von Schadensrisiko und von Managementqualität. Sie legen eindeutige Anforderungen an Kennzahlen für Risiko und Qualität fest. Sie zeigen, wie Risiko und Qualität als komplementäre Steuergrößen für Unternehmensprozesse wirken.
Raus damit! Damit beim Outsourcing nichts schief geht, sind Controlling und Risikomanagement ein Muss
Authors: Gammelin Kai
Published: April 2004

Für Manager ist die Möglichkeit, Teilbereiche des Betriebes an Dritte auszulagern, ein geeignetes Instrument, um Kosten einzusparen und das Unternehmen in beschwerlichen konjunkturellen Schwankungsphasen zu flexibilisieren. Unternehmen, die das beabsichtigen, sind sich allerdings häufig nicht bewusst, dass der Erfolg maßgeblich von der Qualität und Leistung ihres Outsourcing‐Nehmers abhängt. Hinzu kommen Schwierigkeiten bei der internen Ausgestaltung der Anforderungen an ein geeignetes Outsourcing‐Controlling und ‐Risikomanagement. Infolgedessen gab es in den vergangenen Jahren auch nennenswerte Schäden in Unternehmen, die aus der Auslagerung von Teilbereichen resultierten — Fälle, in denen ein schlecht leistender oder insolvent gewordener Outsourcing‐Nehmer nicht nur dem auslagernden Unternehmen, sondern auch weiteren prozessual abhängigen Unternehmen Schwierigkeiten bereitete.
Terrorismus — Gefahr oder Risiko? Gibt es Alternativen zur Bewältigung dieses Phänomens?
Authors: Schneider Oliver
Published: April 2004

Spätestens seit dem 11. September 2001 ist „Terrorismus”︁ einer der meistgebrauchten Begriffe in der öffentlichen Diskussion. Kaum eine Woche vergeht, in der nicht in den Medien über diese Phänomen berichtet wird. Terroristischen Anschlägen, egal ob auf Djerba, auf Bali oder wie erst kürzlich in Istanbul, fallen unschuldige Passanten, Touristen und Geschäftsleute zum Opfer. Die Attentate in Madrid haben auf schreckliche Weise deutlich gemacht, dass Terrorismus auch für uns Europäer eine sehr konkrete Bedrohung darstellt. So hat sich die Überzeugung herausgebildet, dass es Jeden, zu jeder Zeit, an jedem Ort treffen kann. Das subjektive Sicherheitsgefühl der Menschen wird stets aufs Neue negativ beeinflusst. Ein allgemeines, oft diffuses Gefühl der Verletzbarkeit, des Unwohlseins und der Machtlosigkeit hat sich bei vielen breit gemacht. Die allgemeine Forderung nach mehr „Sicherheit”︁ ist dementsprechend immer deutlicher zu vernehmen.
Agieren statt reagieren
Authors: Beller Ursula , Möllemann Klaus
Published: April 2004

Risikomanagement einerseits, Qualitätsmanagement andererseits — zwei Begriffe, mit denen deutsche Unternehmen häufig ein notwendiges Übel verbinden. Gemeinsam eingesetzt, bieten sie eine Reihe von Werkzeugen an, die zur Optimierung des Unternehmenserfolgs beitragen. Wird das Ganze noch durch mess‐ und bewertbare Frühindikatoren ergänzt, entsteht ein Frühindikatorensystem, das die aktuelle Situation des Unternehmens widerspiegelt und entsprechende Entwicklungstendenzen aufzeigt. Dadurch wird das Unternehmen befähigt, Chancen frühzeitig zu nutzen und Risiken entgegenzusteuern.
Risikomanagement darf nicht nur auf dem Papier stehen. Integration von Risikomanagement und Total Quality Management bei Stora Enso Kabel
Authors: Matzke Robert
Published: April 2004

Dass bei einem Papierproduzenten der Fokus des Risikomanagements auf dem Brandschutz liegt, kann sicher nicht überraschen. Stora Enso Kabel hat allerdings schon sehr früh erkannt, dass diese Sichtweise zu einseitig ist. Um eine ganzheitliche Betrachtung der unterschiedlichen Risiken zu erreichen, wurde das Risikomanagement des Unternehmens in das vorhandene Total‐Quality‐Management‐System nach dem Modell von Malcolm Baldrige integriert.
Kontrolle ist besser! Der Deutsche Corporate Governance Kodex (Teil II)
Authors: Dörner Dietrich , Orth Christian
Published: April 2004

Nachdem im ersten Beitrag zum Deutschen Corporate Governance Kodex (siehe RISKNEWS 01/2004, S. 66—71) die Bedeutung „guter Unternehmensführung”︁ dargestellt wurde, beleuchtet der folgende Teil unserer Serie die Hintergründe und Zielsetzungen dieser Regelungen.
Low‐density lipoprotein receptor‐related protein interacts with MafB, a regulator of hindbrain development
Authors: Petersen Helle Heibroch , Hilpert Jan , Jacobsen Christian , Lauwers Annick , Roebroek Anton J.M. , Willnow Thomas E.
Published: April 2004

The intracellular domain (ICD) of the low‐density lipoprotein receptor‐related protein (LRP) functionally interacts with adaptor proteins both as an integral part of the receptor polypeptide and after proteolytic release. Identification of such adaptors has been difficult because the ICD is self‐activating in conventional transcription factor‐based yeast two‐hybrid screens. We adopted an alternative screen for the ICD that depends on the activation of the Ras‐signaling pathway and uncovered the transcription factor MafB as novel ICD interacting protein. MafB is a regulator of hindbrain segmentation and interacts with the ICD through a leucine zipper domain. The ICD co‐localizes with MafB to the nucleus and negatively regulates its transcriptional activity, suggesting a possible role for LRP in brain development.
Evidence that human genes of modular proteins have retained significantly more ancestral introns than their fly or worm orthologues
Authors: Bányai László , Patthy László
Published: April 2004

Comparison of the exon–intron structures of human, fly and worm orthologues of mosaic genes assembled from class 1‐1 modules by exon‐shuffling has revealed that human genes retained significantly more of the original inter‐module introns than their protostome orthologues. It is suggested that the much higher rate of intron loss in the worm‐ and insect lineages than in the chordate lineage reflects their greater tendency for genome compaction.
Transactivation of erbB2 by short and long isoforms of leptin receptors
Authors: Eisenberg Avital , Biener Eva , Charlier Madia , Krishnan R.V. , Djiane Jean , Herman Brian , Gertler Arieh
Published: April 2004

We generated kinase‐positive and kinase‐negative erbB2 tagged with YFP and the long form of leptin receptor (LEPRb) tagged with CFP. Both were as active as their untagged analogs. Both short and long isoforms of leptin receptor phosphorylated and thereby activated erbB2 upon leptin binding and enhanced MAPK activity. Our results unveil a novel route by which leptin may provoke erbB2's phosphorylation and thus enhance its oncogenic potential independently of HER family ligands or its overexpression. Using FRET technology in living cells, we found no evidence of complex formation between erbB2 and prolactin or leptin receptors, indicating that the transactivation occurs through an indirect interaction.
New insights on glycerol transport in Saccharomyces cerevisiae
Authors: Neves Luisa , Lages Fernanda , Lucas Cândida
Published: April 2004

Previous studies evidenced in Saccharomyces cerevisiae the activity of a H+/glycerol symport, derepressed by growth on non‐fermentable carbon sources, later associated with GUP1 and GUP2 genes. It was also demonstrated that only the combined deletion of GUP1, GUP2 together with GUT1 (glycerol kinase) abolished active transport in ethanol‐induced cells. In this work, we show that a glycerol H+/symport, with identical characteristics to the previously described, was found in gup1gup2gut1 grown under salt‐stress, particularly high in cells collected during diauxic‐shift. These results suggest different roles for Gup1/2p than glycerol transport. The gene encoding for glycerol active uptake is thus yet unknown.
In situ acoustic estimates of the swimbladder volume of Atlantic herring (Clupea harengus)
Authors: Nero Redwood W. , Thompson Charles H. , Michael Jech J.
Published: April 2004

Acoustic measurements at 1.5–5 kHz on fish in the Gulf of Maine showed a swimbladder-resonance peak near 2.5 kHz at 160–190-m depth. Midwater trawls confirmed that the fish were likely to be Atlantic herring (Clupea harengus) of 19–29 cm length. Calculation using a model of swimbladder resonance gives swimbladder volumes of 1.2% of fish weight at 160–190 m. Extrapolation of this volume of gas using Boyle's Law suggests that at the sea surface, these herring would need to inflate their swimbladders by up to five to six times the volume required for neutral buoyancy. If these fish were to maintain this volume of gas with surface “gulping”, they would need to submerge from the sea surface with a 30% excess buoyancy. In general, swimbladders of the Clupeidae may have greater volumes of gas than if the fish were neutrally buoyant at the sea surface and the interpretation of HF-echosounder surveys may be additionally complex when the volume of gas and swimbladder volume are difficult to predict. Mechanisms of how herring obtain additional swimbladder gas are discussed.