bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of gene expression profiles in insulin-sensitive tissues from pre-diabetic and diabetic Zucker diabetic fatty rats
Authors: Suh Young Ho , Kim Younyoung , Bang Jeong Hyun , Choi Kyoung Suk , Lee June Woo , Kim Won-Ho , Oh Tae Jeong , An Sungwhan , Jung Myeong Ho 
Published: April 2005

Insulin resistance occurs early in the disease process, preceding the development of type 2 diabetes. Therefore, the identification of molecules that contribute to insulin resistance and leading up to type 2 diabetes is important to elucidate the molecular pathogenesis of the disease. To this end, we characterized gene expression profiles from insulin-sensitive tissues, including adipose tissue, skeletal muscle, and liver tissue of Zucker diabetic fatty (ZDF) rats, a well characterized type 2 diabetes animal model. Gene expression profiles from ZDF rats at 6 weeks (pre-diabetes), 12 weeks (diabetes), and 20 weeks (late-stage diabetes) were compared with age- and sex-matched Zucker lean control (ZLC) rats using 5000 cDNA chips. Differentially regulated genes demonstrating > 1.3-fold change at age were identified and categorized through hierarchical clustering analysis. Our results showed that while expression of lipolytic genes was elevated in adipose tissue of diabetic ZDF rats at 12 weeks of age, expression of lipogenic genes was decreased in liver but increased in skeletal muscle of 12 week old diabetic ZDF rats.
These results suggest that impairment of hepatic lipogenesis accompanied with the reduced lipogenesis of adipose tissue may contribute to development of diabetes in ZDF rats by increasing lipogenesis in skeletal muscle. Moreover, expression of antioxidant defense genes was decreased in the liver of 12-week old diabetic ZDF rats as well as in the adipose tissue of ZDF rats both at 6 and 12 weeks of age. Cytochrome P450 (CYP) genes were also significantly reduced in 12 week old diabetic liver of ZDF rats. Genes involved in glucose utilization were downregulated in skeletal muscle of diabetic ZDF rats, and the hepatic gluconeogenic gene was upregulated in diabetic ZDF rats. Genes commonly expressed in all three tissue types were also observed. These profilings might provide better fundamental understanding of insulin resistance and development of type 2 diabetes.
Effect of inactivating mutations on phosphorylation and internalization of the human VPAC2 receptor
Authors: Langer Ingrid , Langlet Christelle , Robberecht Patrick 
Published: April 2005

The VPAC2 receptor, as all members of the G-protein-coupled receptor (GPCR)-B family, has two highly conserved motifs in the third intracellular (IC3) loop: a lysine and a leucine located at the amino-terminus and two basic residues separated by a leucine and an alanine at the carboxyl-terminus. This study evaluates the involvement of those conserved amino acid sequences in VPAC2 signal transduction and regulation. The residues were mutated into alanine and mutants were expressed in Chinese hamster ovary (CHO) cells stably transfected with Gα16 and aequorin. Mutation of L310 reduced efficacy of vasoactive intestinal polypeptide (VIP) to stimulate adenylate cyclase activity through Gαs coupling by 75%, without affecting VIP capability to stimulate an increase in [Ca2+]i through Gα16 coupling. Mutation of R325 and, to a lesser extend, K328 reduced VIP efficacy to stimulate [Ca2+]i increase and VIP potency to stimulate adenylate cyclase. The combination of mutations of both amino- and carboxyl-terminus located conserved motifs of the IC3 loop generates an inactive receptor with respect to [Ca2+]i increase and adenylate cyclase activation, but also with respect to receptor phosphorylation and internalization that were indeed directly correlated with the potency of inactivation of the receptors.
The amino-terminus of the VPAC2 receptor IC3 loop is thus involved in adenylate cyclase activation and the carboxyl-terminus of the IC3 loop participates in both Gαs and Gα16 coupling. The mutations studied also reduced both receptor phosphorylation and internalization in a manner that appeared directly linked to the alteration of Gαs and Gα16 coupling.
How closely do acute lethal concentration estimates predict effects of toxicants on populations?
Authors: Stark John D. 
Published: April 2005

Abstract
Acute lethal dose/concentration estimates are the most widely used measure of toxicity and these data often are used in ecological risk assessment. However, the value of the lethal concentration (LC50) as a toxicological endpoint for use in ecological risk assessment recently has been criticized. A question that has been asked frequently is how accurate is the LC50 for prediction of longer-term effects of toxicants on populations of organisms? To answer this question, Daphnia pulex populations were exposed to nominal concentrations equal to the 48-h acute LC50 of 6 insecticides, Actara, Aphistar diazinon, pymetrozine, Neemix, and Spinosad; and 8 agricultural adjuvants, Bond, Kinetic, Plyac, R-11, Silwet, Sylgard 309, Water Maxx, and X-77; for 10 d. None of the D. pulex populations exposed to the acute LC50 of these insecticides were 50% lower than the control populations at the end of the study; exposure to diazinon resulted in populations that were higher than expected (91% of the control). Exposure to Actara and Aphistar resulted in populations that were &lt;1 and 29% of the control, respectively. Exposure to Fulfill, Neemix, and Spinosad resulted in extinction. Extinction occurred after exposure to all of the adjuvants, except Silwet L-77 where the population was 31% of the control. These results corroborate other studies that indicate that the LC50 is not a good predictor of effects on population growth. Although lethal concentration estimates have their place in toxicology, namely to compare intrinsic toxicity of chemicals among species or susceptibility of a species to different chemicals over short time periods, population growth and growth-rate studies are necessary to predict toxicant effects on populations.
Indoor air quality investigation and health risk assessment at correctional institutions
Authors: Ofungwu Joseph 
Published: April 2005

Abstract
A comprehensive indoor air–quality (IAQ) investigation was conducted at a state correctional facility in New Jersey, USA with a lengthy history of IAQ problems. The IAQ investigation comprised preliminary indoor air screening using direct readout instrumentation, indoor air/surface wipe sampling and laboratory analysis, as well as a heating, ventilation, and air-conditioning system evaluation, and a building envelope survey. In addition to air sampling, a human health risk assessment was performed to evaluate the potential for exposure to site-related air contaminants with respect to the inmate and worker populations. The risk assessment results for the prison facility indicated the potential for significant health risks for the inmate population, possibly reflecting the effects of their confinement and extended exposure to indoor air contaminants, as compared to the prison guard and worker population. Based on the results of the risk assessment, several mitigation measures are recommended to minimize prison population health risks and improve indoor air quality at prison facilities.
An evaluation of United Kingdom environmental bovine spongiform encephalopathy risk assessment
Authors: Grist Eric P.M. 
Published: April 2005

Abstract
As a member of the group of diseases known as transmissible spongiform encephalopathies (TSEs), bovine spongiform encephalopathy (BSE) has been causally associated with a new variant of Creutzfeldt-Jakob disease (vCJD) in humans. Given the many uncertainties on the transmission and persistence of TSE pathogens in the environment, quantitative assessment of risks to humans and animals continues to remain a public health issue. This paper reviews quantitative BSE risk assessments undertaken in the United Kingdom since 1997 to address the potential for human exposure and theoretical health risks through environmental pathways. The review focuses on how model assumptions and methodology may influence the results.
A methodology for deriving tissue residue benchmarks for aquatic biota: A case study for fish exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin and equivalents
Authors: Steevens Jeffery A. , Reiss Mark R. , Pawlisz Andrew V. 
Published: April 2005

Abstract
Tissue residue-based toxicity benchmarks (TRBs) have typically been developed using the results of individual studies selected from the literature. In the past, TRBs have been developed using a point estimate (e.g., LC50 value) reported in a study on a single species deemed to be most closely related to the receptor of interest. Despite attempts to maximize the protectiveness and relevance of TRBs, their relationship to specific receptors remains uncertain, and their general applicability for use in broader ecological risk assessment contexts is limited. This article proposes a novel framework that establishes benchmarks as distributions rather than single-point estimates. Benchmark distributions allow the user to select a tissue concentration that is associated with the protection of a specific percentage of organisms, rather than linked to a specific receptor. A methodology is proposed for searching, reviewing, and analyzing linked, tissue residue effect data to derive benchmark distributions. The approach is demonstrated for contaminants having a dioxin-like mechanism of toxic action and is based on residue effects data for 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) and equivalents in early life stage fish. The calculated tissue residue benchmarks for 2,3,7,8-TCDD toxic equivalency (TEQ) derived from the resulting distribution could range from 0.057- to 0.699-ng TCDD/g lipid depending on the level of protection needed; the lower estimate is protective of 99% of fish species whereas the higher end is protective of 90% of fish species.
Application of multicriteria decision analysis in environmental decision making
Authors: Kiker Gregory A. , Bridges Todd S. , Varghese Arun , Seager Thomas P. , Linkov Igor 
Published: April 2005

Abstract
Decision making in environmental projects can be complex and seemingly intractable, principally because of the inherent trade-offs between sociopolitical, environmental, ecological, and economic factors. The selection of appropriate remedial and abatement strategies for contaminated sites, land use planning, and regulatory processes often involves multiple additional criteria such as the distribution of costs and benefits, environmental impacts for different populations, safety, ecological risk, or human values. Some of these criteria cannot be easily condensed into a monetary value, partly because environmental concerns often involve ethical and moral principles that may not be related to any economic use or value. Furthermore, even if it were possible to aggregate multiple criteria rankings into a common unit, this approach would not always be desirable because the ability to track conflicting stakeholder preferences may be lost in the process. Consequently, selecting from among many different alternatives often involves making trade-offs that fail to satisfy 1 or more stakeholder groups. Nevertheless, considerable research in the area of multicriteria decision analysis (MCDA) has made available practical methods for applying scientific decision theoretical approaches to complex multicriteria problems. This paper presents a review of the available literature and provides recommendations for applying MCDA techniques in environmental projects. A generalized framework for decision analysis is proposed to highlight the fundamental ingredients for more structured and tractable environmental decision making.
Polymer Blends
Authors: Horák Zdeněk , Fortelný Ivan , Kolařík Jan , Hlavatá Drahomíra , Sikora Antonín 
Published: April 2005

AbstractBlending of two or more different polymers makes it possible to achieve various property combinations of the resulting material—mostly in a more cost‐effective way than by synthesis of new polymers. The resulting multicomponent and mostly heterogeneous blends are an extraordinarily important group of polymer materials, which comprise about a third of the world's polymer production. Common features of preparation, evaluation, and application of polymer blends are the main subject of the chapter.The basic problems associated with the nonequilibrium phase structure and its coarsening, the effects of interfacial energy of components, the strategies of compatibilization of immiscible polymers, and methods of phase structure analysis are elucidated. Special attention is paid to mechanical properties of heterogeneous blends and their prediction. Commercially important types of polymer blends as well as recycling of commingled plastic waste are briefly discussed.
Thermal Analysis of Polymers
Authors: Chartoff Richard P. , Sircar Anil K. 
Published: April 2005

AbstractThermal analysisis defined by the International Confederation of Thermal Analysis and Calorimetry (ICTAC) as “a group of techniques in which a property of a sample is monitored against time or temperature while the temperature of the sample, in a specified atmosphere, is programmed.” The principal techniques employed are differential thermal analysis (DTA), differential scanning calorimetry (DSC), thermogravimetry (TGA), thermomechanical analysis (TMA), dynamic mechanical analysis (DMA), and dielectric analysis (DEA).Chemical reactions and phase transitions as well as mechanical, acoustical, electrical, and optical properties, can be studied and evaluated by thermal analysis. Additional uses include quality control, determination of heat capacity, thermal expansion, thermal and oxidative stability, crystallization rates, phase separation, and numerous others. This article describes the techniques, data interpretation, and applications of the method.
Influence of CO2 on ultrasound‐induced polymerizations in high‐pressure fluids
Authors: Kuijpers M. W. A. , Jacobs L. J. M. , Kemmere M. F. , Keurentjes J. T. F. 
Published: April 2005

AbstractA strong viscosity increase upon polymerization hinders cavitation and subsequent radical formation during an ultrasound‐induced bulk polymerization. Ultrasound‐induced radical polymerizations of methyl methacrylate (MMA) have been performed in CO2‐expanded MMA, as well as in bulk MMA. For this purpose, the phase behavior of CO2/MMA systems has been determined. With temperature oscillation calorimetry, the influence of CO2 on the viscosity and on the reaction kinetics of ultrasound‐induced polymerizations of MMA has been studied. In contrast to polymerizations in bulk, this technique shows that a low viscosity is maintained during polymerization reactions in CO2‐expanded MMA. As a consequence, a constant or even increasing polymerization rate is observed when pressurized CO2 is applied. © 2005 American Institute of Chemical Engineers AIChE J, 2005
Multiple path‐based approach to image‐based street walkthrough
Authors: Lee Dong Hoon , Jung Soon Ki 
Published: April 2005

AbstractImage‐based rendering for walkthrough in the virtual environment has many advantages should over the geometry‐based approach, due to the fast construction of the environment and photo‐realistic rendered results. In image‐based rendering technique, rays from a set of input images are collected and a novel view image is rendered by the resampling of the stored rays. Current such techniques, however, are limited to a closed capture space. In this paper, we propose a multiple path‐based capture configuration that can handle a large‐scale scene and a disparity‐based warping method for novel view generation. To acquire the disparity image, we segment the input image into vertical slit segments using a robust and inexpensive way of detecting vertical depth discontinuity. The depth slit segments, instead of depth pixels, reduce the processing time for novel view generation. We also discuss a dynamic cache strategy that supports real‐time walkthroughs in large and complex street environments. The efficiency of the proposed method is demonstrated with several experiments. Copyright © 2005 John Wiley & Sons, Ltd.
Polymeric Micelles and Nanoparticles from Block and Statistical Poly((RS)‐3,3‐dimethylmalic acid) Derivatives: Preparation and Characterization
Authors: Ouhib Farid , Randriamahefa Solo , Wintgens Véronique , Guérin Philippe , Barbaud Christel 
Published: April 2005

AbstractSummary: Amphiphilic and biodegradable micelles and nanoparticles designed as potential drug carriers were prepared from biodegradable statistical and block copolyesters obtained by a living anionic ring‐opening process. These novel materials display amphiphilic properties arising from the joint presence of hydrophilic poly((RS)‐3,3‐dimethylmalic acid) and hydrophobic poly(hexyl (RS)‐3,3‐dimethylmalate) segments. Micelles obtained from a well‐defined block copolymer have been characterized by their critical aggregation concentration, and nanoparticles derived from statistical copolymer have been analyzed by transmission electron microscopy (TEM).Electron transmission microphotography of nanoparticles of PDMMLAH30‐co‐He70 4.magnified imageElectron transmission microphotography of nanoparticles of PDMMLAH30‐co‐He70 4.
Nanoscale Analysis of Polymer Interfaces by Energy‐Filtering Transmission Electron Microscopy
Authors: Horiuchi Shin , Yin Dehui , Ougizawa Toshiaki 
Published: April 2005

AbstractSummary: Energy‐filtering transmission electron microscopy (EFTEM) was employed for the analysis of polymer‐polymer interfaces. To attain imaging and spectral analyses with a spatial resolution of 10 nm, problems arising in the EFTEM analysis for polymer specimens were investigated. Interfaces in poly(methyl methacrylate)/polystyrene‐co‐polyacrylonitrile random copolymer (PMMA/SAN) bilayer films annealed at different temperatures were analyzed by means of elemental mapping and Image‐EELS on EFTEM and the effect of the annealing temperature on the interfacial structures was also investigated.
magnified image
Diagnostic value of OCT3/4 for pre‐invasive and invasive testicular germ cell tumours
Authors: de Jong Jeroen , Stoop Hans , Dohle Gert R , Bangma Chris H , Kliffen Mike , van Esser Joost WJ , van den Bent Martin , Kros Johan M , Oosterhuis JW , Looijenga Leendert HJ 
Published: April 2005

AbstractHuman testicular germ cell tumours of adolescents and adults (TGCTs), the seminomatous and non‐seminomatous germ cell tumours, show morphological and biological similarities to normal embryonic development, presumably determined by their supposed cell of origin, the primordial germ cell/gonocyte. Based on this knowledge, OCT3/4, also known as POU5F1, was recently defined as a diagnostic marker for these tumour types. In the adult testis, positive immunohistochemistry for OCT3/4 is an absolute indicator for the presence of the TGCT precursor carcinoma in situ/intratubular germ cell neoplasia undifferentiated (CIS/ITGCNU), seminoma, and/or embryonal carcinoma. Several studies have confirmed this observation, using the same polyclonal antibody. The present study demonstrates the usefulness of OCT3/4 immunohistochemistry in a diagnostic setting of a consecutively collected series of more than 200 testicular tumours and over 80 testicular biopsies. Moreover, it is shown that a monoclonal antibody directed against OCT3/4 is as informative as the polyclonal antibody, both in immunohistochemistry and in western blot analysis. The antibodies are robust and applicable with different methods of pretreatment and storage of tissue. This allows routine application of this diagnostic marker. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Evidence that prostate gonadotropin‐releasing hormone receptors mediate an anti‐tumourigenic response to analogue therapy in hormone refractory prostate cancer
Authors: Gnanapragasam VJ , Darby S , Khan MM , Lock WG , Robson CN , Leung HY 
Published: April 2005

AbstractGonadotropin‐releasing hormone analogue (GnRHa) therapy is an established method of androgen withdrawal in the treatment of prostate cancer. The present study investigated if the expression of prostate GnRH receptors (GnRHRs) might influence the response to GnRHa. GnRHR protein expression was first studied in a panel of prostate cancer cell lines. In androgen‐dependent cells, GnRHR expression was unchanged following acute or chronic androgen withdrawal. In these cells, GnRHa significantly inhibited androgen‐induced cell proliferation (p = 0.01). In contrast, GnRHa was unable to further suppress basal levels of cell proliferation induced by androgen withdrawal. In androgen‐independent prostate cancer cells, variable levels of GnRHR expression were observed. In these cells, GnRHa treatment blocked cell proliferation (p = 0.001) and invasion (up to 70%) induced by fibroblast growth factor stimulation. Crucially, this effect was only evident in cells that expressed high levels of the GnRHR. GnRHa treatment also significantly inhibited the ability of these cells to recover from a cytotoxic insult (50% inhibition). The clinical significance of prostate GnRHR was tested by immunohistochemistry in a preliminary cohort of patients treated with GnRHa or surgical castration. There was no association between GnRHR expression and pathological grade, clinical stage, time to PSA nadir (p = 0.82) (n = 35) or progression to hormone refractory disease (p = 0.22) (n = 21), irrespective of the treatment method. GnRHa therapy in the presence of high GnRHR expression however, was found to be associated with longer disease‐specific survival (mean survival 85 months, p = 0.002). In contrast, high GnRHR expression was not associated with survival among surgically castrated patients (mean survival 50 months, p = 0.7). Taken together, these data support the notion of a functional interaction between GnRHa and the GnRHR, which results in an anti‐tumourigenic effect on prostate cancer cells. Findings from this report have direct implications for the use of GnRHR as a novel therapeutic target in hormone refractory prostate cancer. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Structure of poly(L‐lactic acid)s prepared by the dehydropolycondensation of L‐lactic acid with organotin catalysts
Authors: Shyamroy S. , Garnaik B. , Sivaram S. 
Published: April 2005

AbstractThe synthesis of low‐molecular‐weight (weight‐average molecular weight < 45,000 g/mol) lactic acid polymers through the dehydropolycondensation of L‐lactic acid was investigated. Polymerizations were carried out in solution with solvents (xylene, mesitylene, and decalin), without a solvent using different Lewis acid catalysts (tetraphenyl tin and tetra‐n‐butyldichlorodistannoxane), and at three different polymerization temperatures (143, 165, and 190 °C). The products were characterized with differential scanning calorimetry, size exclusion chromatography, vapor pressure osmometry, 13C NMR, and matrix‐assisted laser desorption/ionization time‐of‐flight (MALDI‐TOF). The resulting polymers contained less than 1 mol % lactide, as shown by NMR. The number‐average molecular weights were calculated from the ratio of the area peaks of ester carbonyl and carboxylic acid end groups via 13C NMR. The stereosequences were analyzed by 13C NMR spectroscopy on the basis of triad effects. Tetraphenyl tin was an effective transesterification catalyst, and the randomization of the stereosequence at 190 °C was observed. In contrast, the distannoxane catalyst caused comparatively less transesterification reaction, and the randomization of the stereosequences was slow even at 190 °C. The L‐lactic acid and D‐lactic acid isomers were added to the polymer chain in a small, blocky fashion. The MALDI‐TOF spectra of poly(L‐lactic acid) (PLA) chains doped with Na+ and K+ cations showed that the PLA chains had the expected end groups. The MALDI‐TOF analysis also enabled the simultaneous detection of the cyclic oligomers of PLA present in these samples, and this led to the full structural characterization of the molecular species in PLA. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2164–2177, 2005