bluuebunny/crossref_metadata_2025_split huggingface dataset:
Alterations in endogenous osteogenic protein‐1 with degeneration of human articular cartilage
Authors: Merrihew Charis , Kumar Bhavna , Heretis Katherine , Rueger David C. , Kuettner Klaus E. , Chubinskaya Susan 
Published: April 2003

AbstractA synchronized balance between synthesis and breakdown of extracellular matrix (ECM) molecules in normal articular cartilage is disturbed in osteoarthritis (OA). The focus of our study is the anabolic factor, osteogenic protein‐1 (OP‐1) that is expressed in articular cartilage and is able to induce the synthesis of ECM components. The major aim was to investigate both qualitatively and quantitatively endogenous OP‐1 in normal, degenerative, and OA cartilage. Normal and degenerative cartilage was obtained at autopsies from femoral condyles of human organ donors with no documented history of joint disease; OA cartilage was obtained from patients undergoing joint arthroplasty. Appearance of donor cartilage was evaluated by Collins scale, where normal cartilage is assigned grades 0–1, and degenerated cartilage is assigned grades 2–4. OP‐1 mRNA expression was assessed by RT‐PCR; OP‐1 protein (pro‐ and active forms) was qualitatively analyzed by Western blotting and quantified by OP‐1 ELISA. The highest levels of OP‐1 expression (mRNA and protein) were detected in normal cartilage of grade 0. The concentration of OP‐1 protein was about 50 ng per gram cartilage dry weight. With the progression of cartilage degeneration (increased Collins grades and OA) OP‐1 protein was down‐regulated up to 9‐fold. These changes affected primarily the active form of OP‐1. OP‐1 message also declined in cartilages with the increase of degenerative changes. In conclusion, an overall decrease in endogenous OP‐1 in degenerated and OA tissue suggests that OP‐1 could be one of the factors responsible for normal homeostasis and matrix integrity in cartilage. © 2003 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Tardive dyskinesia is not associated with the polymorphisms of 5-HT2A receptor gene, serotonin transporter gene and catechol-o-methyltransferase gene ⋆
Authors: Herken Hasan , Erdal M. Emin , Böke Ömer , Savaş Haluk A. 
Published: April 2003

AbstractBackgroundThe pathophysiology of tardive dyskinesia (TD) is not completely
understood.AimTo assess the relationship of TD with 5-HT2A receptor gene, serotonin transporter gene (5 HTT), and catechol-o-methyltransferase (COMT) gene polymorphisms.MethodsOur study comprised 111 unrelated subjects who strictly met DSM-IV criteria for schizophrenia and 32 TD, and 79 healthy unrelated controls; all the subjects were of Turkish origin. The analyses of 5-HT2A receptor gene, 5 HTT gene, and COMT gene polymorphisms were performed using polymerase chain reaction (PCR) technique.ResultsThe polymorphisms of these genes were not significantly different between the schizophrenic patients, TD and control subjects.ConclusionsOur findings indicated that 5-HT2A receptor gene, 5 HTT gene, and COMT gene polymorphisms were similar in schizophrenia with non-TD, schizophrenia with TD, and healthy controls. These polymorphisms, though, do not help to evaluate the susceptibility to TD.
Is interval medication a successful treatment regimen for schizophrenic patients with critical attitudes towards treatment?⋆
Authors: Godemann F. , Linden M. , Gaebel W. , Köpke W. , Müller P. , Müller-Spahn F. , Tegeler J. , Pietzcker A. 
Published: April 2003

AbstractIn neuroleptic long-term medication, only part of the patients accept regular intake of neuroleptic drugs. The question is whether an interval medication regimen as opposed to continuous medication can help to reduce drop outs in patients with critical attitudes towards long-term medication. In a 2-year prospective study, 122 patients were randomised to an interval and 164 to a continuous neuroleptic medication regimen. The drop out rates were 62.5% in the interval and 53.7% in the continuous medication group. Drop outs generally show more negative attitudes towards treatment. Patients with negative attitudes do not do better under interval medication. Moreover, this regimen even requires more cooperation and trust in terms of the necessity of medication on the part of the patient compared to the continuous medication regimen. Interval medication therefore is a strategy which can only be successful in highly cooperative, but not in treatment-reluctant patients.
The macroeconomic determinants of technology stock price volatility
Authors: Sadorsky Perry 
Published: April 2003

AbstractStock prices reflect the value of anticipated future profits of companies. Since business cycle conditions impact the future profitability of firms, expectations about the business cycle will affect the current value of firms. This paper uses daily and monthly data from July 1986 to December 2000 to investigate the macroeconomic determinants of US technology stock price conditional volatility. Technology share prices are measured using the Pacific Stock Exchange Technology 100 Index. One of the novel features of this paper is to incorporate a link between technology stock price movements and oil price movements. The empirical results indicate that the conditional volatilities of oil prices, the term premium, and the consumer price index each have a significant impact on the conditional volatility of technology stock prices. Conditional volatilities calculated using daily stock return data display more persistence than conditional volatilities calculated using monthly data. These results further our understanding of the interaction between oil prices and technology share prices and should be of use to investors, hedgers, managers, and policymakers.
Roles of conformational stability and colloidal stability in the aggregation of recombinant human granulocyte colony‐stimulating factor
Authors: Chi Eva Y. , Krishnan Sampathkumar , Kendrick Brent S. , Chang Byeong S. , Carpenter John F. , Randolph Theodore W. 
Published: April 2003

AbstractWe studied the non‐native aggregation of recombinant human granulocyte stimulating factor (rhGCSF) in solution conditions where native rhGCSF is both conformationally stable compared to its unfolded state and at concentrations well below its solubility limit. Aggregation of rhGCSF first involves the perturbation of its native structure to form a structurally expanded transition state, followed by assembly process to form an irreversible aggregate. The energy barriers of the two steps are reflected in the experimentally measured values of free energy of unfolding (ΔGunf) and osmotic second virial coefficient (B22), respectively. Under solution conditions where rhGCSF conformational stability dominates (i.e., large ΔGunf and negative B22), the first step is rate‐limiting, and increasing ΔGunf (e.g., by the addition of sucrose) decreases aggregation. In solutions where colloidal stability is high (i.e., large and positive B22 values) the second step is rate‐limiting, and solution conditions (e.g., low pH and low ionic strength) that increase repulsive interactions between protein molecules are effective at reducing aggregation. rhGCSF aggregation is thus controlled by both conformational stability and colloidal stability, and depending on the solution conditions, either could be rate‐limiting.
Cyclic coordinate descent: A robotics algorithm for protein loop closure
Authors: Canutescu Adrian A. , Dunbrack Roland L. 
Published: April 2003

AbstractIn protein structure prediction, it is often the case that a protein segment must be adjusted to connect two fixed segments. This occurs during loop structure prediction in homology modeling as well as in ab initio structure prediction. Several algorithms for this purpose are based on the inverse Jacobian of the distance constraints with respect to dihedral angle degrees of freedom. These algorithms are sometimes unstable and fail to converge. We present an algorithm developed originally for inverse kinematics applications in robotics. In robotics, an end effector in the form of a robot hand must reach for an object in space by altering adjustable joint angles and arm lengths. In loop prediction, dihedral angles must be adjusted to move the C‐terminal residue of a segment to superimpose on a fixed anchor residue in the protein structure. The algorithm, referred to as cyclic coordinate descent or CCD, involves adjusting one dihedral angle at a time to minimize the sum of the squared distances between three backbone atoms of the moving C‐terminal anchor and the corresponding atoms in the fixed C‐terminal anchor. The result is an equation in one variable for the proposed change in each dihedral. The algorithm proceeds iteratively through all of the adjustable dihedral angles from the N‐terminal to the C‐terminal end of the loop. CCD is suitable as a component of loop prediction methods that generate large numbers of trial structures. It succeeds in closing loops in a large test set 99.79% of the time, and fails occasionally only for short, highly extended loops. It is very fast, closing loops of length 8 in 0.037 sec on average.
Neural Correlates of Lexical Access during Visual Word Recognition
Authors: Binder J. R. , McKiernan K. A. , Parsons M. E. , Westbury C. F. , Possing E. T. , Kaufman J. N. , Buchanan L. 
Published: April 2003

Abstract
People can discriminate real words from nonwords even when the latter are orthographically and phonologically word-like, presumably because words activate specific lexical and/or semantic information. We investigated the neural correlates of this identification process using event-related functional magnetic resonance imaging (fMRI). Participants performed a visual lexical decision task under conditions that encouraged specific word identification: Nonwords were matched to words on orthographic and phonologic characteristics, and accuracy was emphasized over speed. To identify neural responses associated with activation of nonsemantic lexical information, processing of words and nonwords with many lexical neighbors was contrasted with processing of items with no neighbors. The fMRI data showed robust differences in activation by words and word-like nonwords, with stronger word activation occurring in a distributed, left hemisphere network previously associated with semantic processing, and stronger nonword activation occurring in a posterior inferior frontal area previously associated with grapheme-to-phoneme mapping. Contrary to lexicon-based models of word recognition, there were no brain areas in which activation increased with neighborhood size. For words, activation in the left prefrontal, angular gyrus, and ventrolateral temporal areas was stronger for items without neighbors, probably because accurate responses to these items were more dependent on activation of semantic information. The results show neural correlates of access to specific word information. The absence of facilitatory lexical neighborhood effects on activation in these brain regions argues for an interpretation in terms of semantic access. Because subjects performed the same task throughout, the results are unlikely to be due to task-specific attentional, strategic, or expectancy effects.
Meat Is Good to Taboo: Dietary Proscriptions as a Product of the Interaction of Psychological Mechanisms and Social Processes
Authors: Fessler Daniel , Navarrete Carlos David 
Published: April 2003

Abstract
Comparing food taboos across 78 cultures, this paper demonstrates that meat, though a prized food, is also the principal target of proscriptions. Reviewing existing explanations of taboos, we find that both functionalist and symbolic approaches fail to account for meat's cross-cultural centrality and do not reflect experience-near aspects of food taboos, principal among which is disgust. Adopting an evolutionary approach to the mind, this paper presents an alternative to existing explanations of food taboos. Consistent with the attendant risk of pathogen transmission, meat has special salience as a stimulus for humans, as animal products are stronger elicitors of disgust and aversion than plant products. We identify three psychosocial processes, socially-mediated ingestive conditioning, egocentric empathy, and normative moralization, each of which likely plays a role in transforming individual disgust responses and conditioned food aversions into institutionalized food taboos.
Pituitary Corticotroph Ontogeny and Regulation in Transgenic Zebrafish
Authors: Liu Ning-Ai , Huang Haigen , Yang Zhongan , Herzog Wiebke , Hammerschmidt Matthias , Lin Shuo , Melmed Shlomo 
Published: April 2003

AbstractWe characterized zebrafish proopiomelanocortin (POMC) gene promoter, and sequence analysis revealed that the promoter contains regulatory elements conserved among vertebrate species. To monitor the ontogeny of the pituitary POMC lineage in living vertebrates, we generated transgenic zebrafish expressing green fluorescent protein (GFP) driven by the POMC promoter. Zebrafish POMC-GFP is first expressed asymmetrically as two bilateral groups of cells most anterior to the neural ridge midline at 18–20 h post fertilization (hpf). POMC-GFP-positive cells then fuse into a single-cell mass within the pituitary anlage after 24 hpf and subsequently organize as distinct anterior and posterior domains between 48 and 64 hpf. Immunohistochemical studies with ACTH and αMSH antisera showed that POMC-GFP was mainly targeted to both anterior and posterior pituitary corticotrophs, whereas posterior pituitary region melanotrophs did not express GFP. To determine in vivo zebrafish corticotroph responses, dexamethasone (10−5m) was added to live embryos, which selectively suppressed POMC-GFP expression in the anterior group of corticotrophs, suggesting a distinct domain that is responsive to glucocorticoid feedback. Transgenic zebrafish with specific POMC-GFP expression in pituitary corticotrophs offers a powerful genetic system for in vivo study of vertebrate corticotroph lineage development.
Modelling sources and sinks of CO2, H2O and heat within a Siberian pine forest using three inverse methods
Authors: Siqueira M. , Leuning R. , Kolle O. , Kelliher F. M. , Katul G. G. 
Published: April 2003

AbstractSource/sink distributions of heat, CO2 and water vapour in a Siberian Scots pine forest were estimated from measured concentration and temperature profiles using three inverse analysis methods. These methods include: a Eulerian second‐order closure model (EUL); a localized near‐field Lagrangian dispersion model (LNF); and a hybrid model (HEL) which uses the Eulerian second‐order turbulence model to calculate the flow statistics combined with the regression analysis used with the Lagrangian model. Model predictions were compared to heat flux profiles measured at five levels in the canopy, and to CO2 and water‐vapour fluxes measured close to the ground and above the forest. Predictions of sensible‐heat flux profiles by the LNF and HEL schemes were systematically better than results from the EUL analysis. This improvement was attributed to the redundancy in the measured profile (scalar concentration and temperature) data for LNF and HEL and to the imposed smoothness condition used in the regression analyses, whereas the EUL approach calculates a source for each level without any redundancy. The LNF and HEL schemes were also better than EUL in predicting source distributions for CO2 and water vapour, although errors were larger than for sensible heat. The main novelty in our study is the use of EUL to decompose the vertical variability in scalar (or heat) sources into variability produced by the inhomogeneity in flow statistics and variability inferred from the measured mean scalar concentration (or temperature) profile. Hence, it is possible with this analysis to assess how much ‘new information’ about the source variability is attributed to vertical variation in the measured mean scalar concentration (or temperature) profiles. The analysis shows that measured water vapour concentration profiles provide little information on the inferred source distribution, whereas the CO2 profiles contain more information. Monte Carlo simulations show that computed sources from all three inverse methods have similar sensitivities to errors in measured temperatures. Errors are reduced when the reference temperature above the canopy is held fixed, implying that errors in this temperature propagate throughout the entire domain. When information content and error estimations are combined, a valuable tool to assess the quality of source prediction by inverse methods can be generated. Copyright © 2003 Royal Meteorological Society
Carbimazole-Related Gastroschisis
Authors: Guignon Anne-Maëlle , Mallaret Michel P , Jouk Pierre Simon 
Published: April 2003

OBJECTIVE: To report a case of gastroschisis in a newborn secondary to carbimazole exposure in utero. CASE SUMMARY: A 25-year-old white woman was treated for Graves disease with carbimazole throughout pregnancy. A boy was born prematurely by vaginal delivery, with a gastroschisis without associated malformative syndrome. Death occurred in the 25th hour of life after surgical repair. DISCUSSION: Carbimazole is completely metabolized to methimazole after absorption. Carbimazole or methimazole intake during pregnancy has been associated with an increased incidence of scalp aplasia. Abdominal wall defects secondary to carbimazole or methimazole exposure in utero seem to be a rare occurrence. However, other cases of abdominal wall defects have been reported in 4 newborns, 2 of them associated with scalp aplasia. An objective causality assessment revealed that the relationship between the gastroschisis and the exposure to carbimazole in utero was possible. CONCLUSIONS: It is important to emphasize the possible risk of abdominal wall defects in newborns to pregnant women taking carbimazole or methimazole.
Preparation and properties of waterborne polyurethanes for water‐vapor‐permeable coating materials
Authors: Kwak Yong‐Sil , Park Sang‐Woo , Lee Young‐Hee , Kim Han‐Do 
Published: April 2003

AbstractWaterborne polyurethanes were prepared by polyaddition reaction using isophorone diisocyanate, dimethylol propionic acid, various polyols with a fixed molecular weight (Mn = about 2000), ethylene diamine as a chain extender, and triethylamine as a neutralization agent. Three types of polyols such as (1) solo glycols [polypropylene glycol (PPG) (Mn = 2000), poly(tetramethylene oxide) glycol (PTMG) (Mn = 2000), poly(tetramethylene adipate glycol) (PTAd) (Mn = 2000), or polycaprolactone glycol (PCL) (Mn = 2000)], (2) the polyol blends (PPG/PCL, PTMG/PCL, PPG/PTAd, PTMG/PTAd), and (3) a triblock glycol (TBG) (Mn = 1990) were used in this study. The triblock glycol (TBG) [(CL)4.5–PTMG (Mn = 1000)–(CL)4.5 (Mn =1990] was synthesized from PTMG and ϵ‐caprolactone (CL) in this study. The triblock glycol was found to have two main melting peaks at about 13 and 40°C. This study was examined on the effect of the types of polyols on the particle size, viscosity, dynamic thermal properties, and water vapor permeability. The particle size of the aqueous polyurethane–urea dispersion increased in the order of polyol‐blends‐based samples (183–350 nm) > TBG‐based sample (167 nm) > solo‐polyol‐based sample (58–96 nm). By dynamic thermal mechanical analysis, the ester‐type polyol‐ (PTAd and PCL) based samples were found to have higher storage modulus and Tg than those of ether‐type polyol‐ (PPG and PTMG) based samples. The water vapor permeability (WVP) increased in the order of TGB‐based sample > PCL/PTMG‐based sample > PTAd/PTMG‐based sample > PCL/PPG‐based sample > PTAd/PPG‐based sample > PTMG‐based sample > PPG‐based sample > PCL‐based sample > PTAd‐based sample. WVP was found to increase in the order of TBG‐based sample > polyol‐blend based samples > solo‐polyol‐based samples. It was also found that the samples containing ether‐type glycols (PTMG, PPG) had higher permeability than samples having ester‐type glycols (PCL, PTAd). PTMG‐based samples were found to have higher permeability than PPG‐based samples if other compositions were constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 123–129, 2003
Pressure and cooling rate‐induced densification of atactic polystyrene
Authors: Pantani Roberto 
Published: April 2003

AbstractThe exact knowledge of postprocessing polymer‐specific volume is often a factor of enormous strategic importance from an industrial point of view. The subject is complicated by the fact that the specific volume of solid polymers at a constant temperature and pressure is not only a function of the current temperature and pressure, but is also a consequence of the whole formation history from the melt. In this work, specific volumes of samples solidified in different conditions are analyzed and related to their formation history. A wide range of cooling rates (from 5 × 10−3 to 300 K/s) and solidification pressures (from 0.1 to 80 MPa) are examined. The results show a synergic effect of the cooling rate and solidification pressure: Lower cooling rates result in a much higher pressure‐induced densification with respect to higher cooling rates. A simple phenomenological model which essentially links the densification effect to the dependence of the glass transition temperature upon the cooling rate and solidification pressure is adopted to describe the experimental data. Starting from the densification effect, the effect of the pressure and cooling rate on the glass transition temperature is evaluated. Furthermore, some conclusions about the dependence of the volume relaxation time on the temperature and pressure in the glass transition range are achieved. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 184–190, 2003
Borrelien: zeitgerechter Wirtswechsel
Authors: Erdnüß Frank 
Published: April 2003

AbstractBorrelien exprimieren bestimmte Oberflächenproteine, die zum Übertritt von der Zecke in den Warmblüter notwendig sind. Die Proteinsynthese erfolgt zeitgerecht, je nachdem, welche Zeckenart als Zwischenwirt genutzt wird. Die Erkenntnisse können die Entwicklung eines Borreliose‐Impfstoffes beeinflussen.
Molekulargenetik im Artenschutz: Schutz der Europäischen Sumpfschildkröte
Authors: Poschadel Jens R. , Parzefall Jakob 
Published: April 2003

AbstractEine neue entwickelte Feldmethode macht die DNA‐Extraktion aus der Mundschleimhaut geschützter Vertebraten im Freiland sowie im Labor möglich. Die Methode fand bei der Probenahme zur Ermittlung der genetischen Variabilität in drei ausgewählten europäischen Gebieten mit insgesamt 13 Populationen der Europäischen Sumpfschildkröte Emys orbicularis Verwendung. Die Analyse der gewonnenen Proben ergab einen Gradienten in der Variabilität des gewählten genetischen Markers von der hoch diversen Region des Doñana Nationalparks im Südwesten von Spanien über die deutlich weniger diversen Populationen Ostpolens bis hin zur Inzuchtsituation bei brandenburgischen Reliktpopulationen.