bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment of blind predictions of protein–protein interactions: Current status of docking methods
Authors: Méndez Raúl , Leplae Raphaël , De Maria Leonardo , Wodak Shoshana J.
Published: May 2003

The current status of docking procedures for predicting protein–protein interactions starting from their three‐dimensional structure is assessed from a first major evaluation of blind predictions. This evaluation was performed as part of a communitywide experiment on Critical Assessment of PRedicted Interactions (CAPRI). Seven newly determined structures of protein–protein complexes were available as targets for this experiment. These were the complexes between a kinase and its protein substrate, between a T‐cell receptor β‐chain and a superantigen, and five antigen‐antibody complexes. For each target, the predictors were given the experimental structures of the free components, or of one free and one bound component in a random orientation. The structure of the complex was revealed only at the time of the evaluation. A total of 465 predictions submitted by 19 groups were evaluated. These groups used a wide range of algorithms and scoring functions, some of which were completely novel. The quality of the predicted interactions was evaluated by comparing residue–residue contacts and interface residues to those in the X‐ray structures and by analyzing the fit of the ligand molecules (the smaller of the two proteins in the complex) or of interface residues only, in the predicted versus target complexes. A total of 14 groups produced predictions, ranking from acceptable to highly accurate for five of the seven targets. The use of available biochemical and biological information, and in one instance structural information, played a key role in achieving this result. It was essential for identifying the native binding modes for the five correctly predicted targets, including the kinase‐substrate complex where the enzyme changes conformation on association. But it was also the cause for missing the correct solution for the two remaining unpredicted targets, which involve unexpected antigen‐antibody binding modes. Overall, this analysis reveals genuine progress in docking procedures but also illustrates the remaining serious limitations and points out the need for better scoring functions and more effective ways for handling conformational flexibility. Proteins 2003;52:51–67. © 2003 Wiley‐Liss, Inc.
Successful discrimination of protein interactions
Authors: Camacho Carlos J. , Gatchell David W.
Published: May 2003

We present results from the prediction of protein complexes associated with the first Critical Assessment of PRediction of Interactions (CAPRI) experiment. Our algorithm, SmoothDock, comprises four steps: (1) we perform rigid body docking using the program DOT, keeping the top 20,000 structures as ranked by surface complementarity; (2) we rerank these structures according to a free energy estimate that includes both desolvation and electrostatics and retain the top 2000 complexes; (3) we cluster the filtered complexes using a pairwise root‐mean‐square deviation (RMSD) criterion; (4) the 25 largest clusters are subject to a smooth docking discrimination algorithm where van der Waals forces are taken into account. We predicted targets 1, 6, and 7 with RMSDs of 9.5, 2.4, and 2.6 Å, respectively. More importantly, from the perspective of biological applications, our approach consistently ranked the correct model first (i.e., with highest confidence). For target 5 we identified the binding region but not the correct orientation. Although we were able to find reasonable clusters for all targets, low‐affinity complexes (Kd < nM) were harder to discriminate. For four of seven targets, the top models predicted by our automated procedure were among the best communitywide predictions. Proteins 2003;52:92–97. © 2003 Wiley‐Liss, Inc.
Finding needles in haystacks: Reranking DOT results by using shape complementarity, cluster analysis, and biological information
Authors: Law Dennis S. , Ten Eyck Lynn F. , Katzenelson Omer , Tsigelny Igor , Roberts Victoria A. , Pique Mike E. , Mitchell Julie C.
Published: May 2003

We present an evaluation of our results for the first Critical Assessment of PRedicted Interaction (CAPRI). The methods used include the molecular docking program DOT, shape analysis tool FADE, cluster analysis and filtering based on biological data. Good results were obtained for most of the seven CAPRI targets, and for two systems, submissions having the highest number of correctly predicted contacts were produced. Proteins 2003;52:33–40. © 2003 Wiley‐Liss, Inc.
Evaluation of the 3D‐Dock protein docking suite in rounds 1 and 2 of the CAPRI blind trial
Authors: Smith Graham R. , Sternberg Michael J.E.
Published: May 2003

The 3D‐Dock suite of programs has been used to make predictions for the seven targets in rounds 1 and 2 of the CAPRI method evaluation exercise. Some correct contacts were obtained in at least one prediction for four of seven targets. Target 06 was predicted very well, with an RMSD of the ligand after superimposition of the receptor of only 0.77 Å. We investigate the performance of the various stages of the method, with the aim of finding where improvements need to be made, and in particular whether the manual interventions that were made were essential, and whether results of the level of accuracy obtained for target 06 may be expected with confidence. Proteins 2003;52:74–79. © 2003 Wiley‐Liss, Inc.
Taking geometry to its edge: Fast unbound rigid (and hinge‐bent) docking
Authors: Schneidman‐Duhovny Dina , Inbar Yuval , Polak Vladimir , Shatsky Maxim , Halperin Inbal , Benyamini Hadar , Barzilai Adi , Dror Oranit , Haspel Nurit , Nussinov Ruth , Wolfson Haim J.
Published: May 2003

We present a very efficient rigid “unbound” soft docking methodology, which is based on detection of geometric shape complementarity, allowing liberal steric clash at the interface. The method is based on local shape feature matching, avoiding the exhaustive search of the 6D transformation space. Our experiments at CAPRI rounds 1 and 2 show that although the method does not perform an exhaustive search of the 6D transformation space, the “correct” solution is never lost. However, such a solution might rank low for large proteins, because there are alternatives with significantly larger geometrically compatible interfaces. In many cases this problem can be resolved by successful a priori focusing on the vicinity of potential binding sites as well as the extension of the technique to flexible (hinge‐bent) docking. This is demonstrated in the experiments performed as a lesson from our CAPRI experience. Proteins 2003;52:107–112. Published 2003 Wiley‐Liss, Inc.
Fold recognition with minimal gaps
Authors: Chen William , Mirny Leonid , Shakhnovich Eugene I.
Published: May 2003

Here we present a simplified form of threading that uses only a 20 × 20 two‐body residue‐based potential and restricted number of gaps. Despite its simplicity and transparency the Monte Carlo‐based threading algorithm performs very well in a rigorous test of fold recognition. The results suggest that by simplifying and constraining the decoy space, one can achieve better fold recognition. Fold recognition results are compared with and supplemented by a PSI‐BLAST search. The statistical significance of threading results is rigorously evaluated from statistics of extremes by comparison with optimal alignments of a large set of randomly shuffled sequences. The statistical theory, based on the Random Energy Model, yields a cumulative statistical parameter, ϵ, that attests to the likelihood of correct fold recognition. A large ϵ indicates a significant energy gap between the optimal alignment and decoy alignments and, consequently, a high probability that the fold is correctly recognized. For a particular number of gaps, the ϵ parameter reaches its maximal value, and the fold is recognized. As the number of gaps further increases, the likelihood of correct fold recognition drops off. This is because the decoy space is small when gaps are restricted to a small number, but the native alignment is still well approximated, whereas unrestricted increase of the number of gaps leads to rapid growth of the number of decoys and their statistical dominance over the correct alignment. It is shown that best results are obtained when a combination of one‐, two‐, and three‐gap threading is used. To this end, use of the ϵ parameter is crucial for rigorous comparison of results across the different decoy spaces belonging to a different number of gaps. Proteins 2003;51:531–543. © 2003 Wiley‐Liss, Inc.
The effects of die shapes and additives on the physical and biodegradable properties of biodegradable cushioning extruded foams
Authors: Lui Wai‐Bun , Peng Jinchyau
Published: June 2003

In this study, efforts were focused on the effects of the operating parameters, i.e. die shapes (DS), PVA ratio (PR), additives (AT) on the physical and biodegradable properties of the corn/PVA extrudates. We also evaluated the extrudates as cushioning materials. The process variables were the operating, conditions, die shapes (○, ∞, ▵ and O), PVA ratio (40%, 50%, 60%) and additives [sodium bicarbonate (NaHCO3), calcium carbonate (CaCO3) and calcium hydroxide (Ca(OH)2)]. The experiment is a 4 × 3 × 3 factorial design. Samples of each treatment were collected and the physical, mechanical and chemical properties were measured and analysed using the PROC ANOVA and PROC CORR of the SAS 6.0 software package.35 The experimental results indicated that: (a) The change of die shapes (DS) had a significant effect on the longitudinal expansion, bulk density, compressibility and biodegradability properties of the extrudates; (b) the change of PVA ratio (PR) had a significant effect on the longitudinal expansion, bulk density and compressibility, but no effect on the biodegradability properties of the extrudates; and (c) the change of additives (AT) had a significant effect on the longitudinal expansion, bulk density and compressibility, but no effect on the spring index of the extrudates. Copyright © 2003 John Wiley & Sons, Ltd.
Packaging scorecard – a packaging performance evaluation method
Authors: Olsmats Carl , Dominic Chris
Published: June 2003

To support a more holistic approach to the contribution of packaging to efficiency and value creation in the product supply chain, a systematic evaluation method – packaging scorecard – has been developed and tested in two case studies. The packaging scorecard is based on research of functional criteria of packaging and the theories of ‘balanced scorecard’, a general management approach to evaluating organizational performance using different perspectives. The results of the case studies indicate that the method can be very useful to get a systematic overview of packaging performance throughout the product supply chain. Copyright © 2003 John Wiley & Sons, Ltd.
Evaluation of a UV absorber added to PET bottles for edible oil packaging
Authors: Coltro Leda , Padula Marisa , Saron Elisabete Segantini , Borghetti Joyce , Buratin Ana Elisa Penteado
Published: June 2003

The photo‐oxidation of lipids has significant effects on the quality of edible oils. The oxidation of oils and fats can begin due to the action of external energy sources such as light. Studies showed that the rate of photo‐oxidation of the oil depends on the light transmission of the packaging, the product characteristics and the O2 barrier of the packaging. The UV absorber 2‐(2′‐hydroxy‐3′‐tert‐butyl‐5′‐methylphenyl)‐5‐chlorobenzotriazole (Tinuvin 326™) has been used in PET bottles for oil, making possible the reduction of the photo‐oxidation rates. This additive was approved recently by the European Union and included in the Positive List of Directive 2001/62/EC, with a limit of specific migration. This additive is also approved by the Mercosur legislation; nevertheless its restriction of use is being reviewed in Brazil. This study had the objectives of evaluating the efficiency of the additive through the determination of the light barrier properties of PET bottles with various levels of Tinuvin 326™ and of verifying its suitability for use in direct contact with foods. Copyright © 2003 John Wiley & Sons, Ltd.
Fuzzy logic controller in a packaging plant
Authors: Braglia Marcello , Frosolini Marco , Montanari Roberto
Published: June 2003

This paper deals with the analysis of a controller used to synchronize two parallel belt conveyors in a packaging plant. A first conveyor carries the products, while the second delivers the packages. The insertion is obtained by a proper mechanical action. The control system is based on a ‘hybrid’ fuzzy logic controller, whose parameters are optimized by using an advanced ‘operational’ genetic algorithm. ‘Hybrid’ means that a conventional fuzzy logic controller is integrated with a set of special rules needed to solve particular situations characterizing the system. An important constraint is given, since the physical structure of the existing control system is to be kept unchanged. It is shown that the controller efficiently governs the belt conveyors when: (a) the distances between goods and the relative packages become higher than a certain value; (b) the performance of the electrical engine deteriorates during working time; and also (c) interference phenomena occur between consecutive good‐package couples. Copyright ©2003 John Wiley & Sons, Ltd.
Output regulation of discrete‐time linear plants subject to state and input constraints
Authors: Shi Guoyong , Saberi Ali , Stoorvogel Anton A. , Sannuti Peddapullaiah
Published: May 2003

Discrete‐time output regulation of linear systems with state and/or input constraints on magnitude is considered. Structural properties of linear plants are identified under which the so‐called constrained semi‐global and global output regulation problems are solvable. As in the case of continuous‐time systems, an important aspect of our development is a taxonomy of constraints showing a clear relationship between the constraint types and the output regulation results. Solvability conditions are developed for semi‐global and global output regulation problems. Appropriate regulators are constructed for problems that are solvable. Copyright © 2003 John Wiley & Sons, Ltd.
Robustness analysis of flexible structures: practical algorithms
Authors: Ferreres Gilles , Magni Jean‐François , Biannic Jean‐Marc
Published: May 2003

When analysing the robustness properties of a flexible system, the classical solution, which consists of computing lower and upper bounds of the structured singular value (s.s.v.) at each point of a frequency gridding, appears unreliable. This paper describes two algorithms, based on the same technical result: the first one directly computes an upper bound of the maximal s.s.v. over a frequency interval, while the second one eliminates frequency intervals, inside which the s.s.v. is guaranteed to be below a given value. Various strategies are then proposed, which combine these two techniques, and also integrate methods for computing a lower bound of the s.s.v. The computational efficiency of the scheme is illustrated on a real‐world application, namely a telescope mock‐up which is significant of a high order flexible system. Copyright © 2003 John Wiley & Sons, Ltd.
On theLp(ℓp) stabilization of open‐loop neutrally stable linear plants with input subject to amplitude saturation
Authors: Shi Guoyong , Saberi Ali , Stoorvogel Anton A.
Published: May 2003

It has been shown that for asymptotically null controllable linear systems with input saturation and non‐input‐additive disturbances, there existnonlinearcontrol laws that achieve global stabilization andLp(ℓp) stabilization without finite‐gain for any p∈[1,∞). Recently, it also has been shown that for a simple double integrator there is no saturated linear controller that can achieveLpstabilization forp>2. In this paper, we show that if a linear system is open‐loop neutrally stable and stabilizable then there exist saturatedlinearcontrol laws that achieveLp(ℓp) stability for anyp∈[1,∞) and for arbitrary initial conditions. As a byproduct, we also show that the closed‐loop system with a saturated linear control law has a nice property similar to linear systems, i.e., any vanishing disturbance produces a vanishing state with arbitrary initial condition. Copyright © 2003 John Wiley & Sons, Ltd.
Robust stability, stabilization and ℋ∞ control of time‐delay systems with Markovian jump parameters
Authors: Mahmoud Magdi S. , Shi Peng
Published: May 2003

In this paper, the problems of stochastic stability and stabilization for a class of uncertain time‐delay systems with Markovian jump parameters are investigated. The jumping parameters are modelled as a continuous‐time, discrete‐state Markov process. The parametric uncertainties are assumed to be real, time‐varying and norm‐bounded that appear in the state, input and delayed‐state matrices. The time‐delay factor is constant and unknown with a known bound. Complete results for both delay‐independent and delay‐dependent stochastic stability criteria for the nominal and uncertain time‐delay jumping systems are developed. The control objective is to design a state feedback controller such that stochastic stability and a prescribed ℋ∞‐performance are guaranteed. We establish that the control problem for the time‐delay Markovian jump systems with and without uncertain parameters can be essentially solved in terms of the solutions of a finite set of coupled algebraic Riccati inequalities or linear matrix inequalities. Extension of the developed results to the case of uncertain jumping rates is also provided. Copyright © 2003 John Wiley & Sons, Ltd.
Physicochemical Properties of Sweet Potato Flour and Starch as Affected by Blanching and Processing
Authors: Jangchud Kamolwan , Phimolsiripol Yuthana , Haruthaithanasan Vichai
Published: June 2003

The effects of blanching on physicochemical properties of flours and starches prepared from two varieties of sweet potatoes (Mun‐Kai and Negro) were studied and compared. The pasting temperature and peak viscosity of starches, respectively, were 74 and 80 °C and 381 and 433 RVU. The pasting temperature (74.0‐94.8 °C) of flours was greater than that of starch, depending on the variety and blanching process. However, the peak viscosity (ca. 103‐120 RVU) of flours was lower than that of the corresponding starches. Partial gelatinization of starch granules was observed as a result of a 1‐min blanching. Composition of starch and flour was found to affect swelling power and solubility. The starch content of starches, flours from unblanched sweet potato and flours from 1‐min blanched sweet potatoes were 97; 66.3 and 74.9; as well as 36.6 and 40.4%, respectively. Amylose content of flours and starches varied from 17.2‐20.8%.
Analysis of Variations in the Amylose Content of Grains Located at Different Positions in the Rice Panicle and the Effect of Milling
Authors: Zhang Xiao‐Ming , Shi Chun‐Hai , Wu Jian‐Guo , Hisamitus Horiuchi , Katsura Tomita , Feng Shui‐Ying , Bao Gen‐Liang , Ye Sheng‐Hai
Published: June 2003

The results of the presented study indicated that the amylose content (AC) of individual rice kernels varied among grains in the same panicle and even in outer and inner layers of the same grain. The differences among the grains in panicles were 19.1% in the Indica variety “Zhenong 5” and 22.8% in the Japonica variety “Zhehu 9827”. The amylose content of the grains in the upper position or the first branches of panicles and of the early flowering grains or heavier grains was higher than that of others. Amylose content increases by 1.36% in Japonica rice variety “Zhehu 9827” and 1.92% in Indica rice variety “Zhenong 5”, when the degree of milling increases by 10%. The tendency of changes in AC was the same for grains of the Japonica and the Indica rice variety. Furthermore, for analyzing AC the grains in a panicle should carefully be selected. Errors coming from sampling could be decreased by using a multiplicity of grains rather than single‐grain samples.
Isolation and characterization of the TRP1 gene from the yeast Yarrowia lipolytica and multiple gene disruption using a TRP blaster
Authors: Cheon Seon Ah , Han Eun Jung , Kang Hyun Ah , Ogrydziak David M. , Kim Jeong‐Yoon
Published: June 2003

The TRP1 gene encoding N‐(5′‐phosphoribosyl)‐anthranilate isomerase was isolated from the yeast Yarrowia lipolytica, in which only a few genetic marker genes are available. The Y. lipolytica TRP1 gene (YlTRP1) cloned by complementation of Y. lipolytica trp1 mutation was found to be a functional homologue of Saccharomyces cerevisiae TRP1. Since YlTRP1 could be used for counterselection in medium containing 5‐fluoroanthranilic acid (5‐FAA), we constructed TRP blasters that contained YlTRP1 flanked by a direct repeat of a sequence and allowed the recycling of the YlTRP1 marker. Using the TRP blasters the sequential disruption of target genes could be carried out within the same strain of Y. lipolytica. The nucleotide sequence of the YlTRP1 gene has been deposited at GenBank under Accession No. AF420590. Copyright © 2003 John Wiley & Sons, Ltd.
Relationship between G+C content, ORF‐length and mRNA concentration in Saccharomyces cerevisiae
Authors: Marín Antonio , Gallardo Mercedes , Kato Yuki , Shirahige Katsuhiko , Gutiérrez Gabriel , Ohta Kunihiro , Aguilera Andrés
Published: June 2003

RNA biogenesis is a tightly‐regulated process. The levels and timing of expression of a gene depends on its particular function. However, gene expression levels may also depend on structural features. Here we describe the analysis of gene expression of 4977 ORFs using DNA microarrays covering the whole genome of three different S. cerevisiae strains, wild‐type and tho2 and thp1 mutants with a general effect on mRNA biogenesis. We show that transcripts from G+C‐rich ORFs accumulate at higher concentrations than those from G+C‐poor ones, in different ORF‐length categories in all strains tested. In addition, we found a negative correlation between ORF length and G+C content. Our results indicate that length and G+C content of a gene have a clear effect on its levels of expression. We discuss the biological relevance of these results, as well as different ways that these structural features could modulate mRNA biogenesis. Copyright © 2003 John Wiley & Sons, Ltd.
Candida albicans TDH3 gene promotes secretion of internal invertase when expressed in Saccharomyces cerevisiae as a glyceraldehyde‐3‐phosphate dehydrogenase‐invertase fusion protein
Authors: Delgado M. Luisa , Gil M. Luisa , Gozalbo Daniel
Published: June 2003

We have checked the ability of the Candida albicans GAPDH polypeptide, which lacks a conventional N‐terminal signal peptide, to reach the cell wall in Saccharomyces cerevisiae by using an intracellular form of the yeast invertase as a reporter protein. A hybrid TDH3–SUC2 gene containing the C. albicans TDH3 promoter sequences and a coding region encoding a fusion protein formed by the C. albicans GAPDH polypeptide, fused at its C‐terminus with the yeast internal invertase, was constructed in a centromer derivative plasmid and transformed into a Suc− S. cerevisiae strain. Transformants displayed invertase activity measured in intact whole cells, and were able to grow on sucrose as the sole fermentable carbon source. Northern blot analysis with both TDH3 and SUC2 probes detected a single mRNA species of the expected size (about 2.7 kb), and Western immunoblot analysis of cell‐free extracts, using a monoclonal antibody (mAb49) against a C. albicans GAPDH epitope, showed the presence of a 90 kDa polypeptide corresponding to the GAPDH‐invertase fusion protein. This indicates that the TDH3 gene is able to direct part of the encoded gene product to the cell wall, and that any putative motifs for this targeting should be within the GAPDH amino acid sequence. Further analysis, using the same approach, of a panel of seven N‐ and C‐terminal GAPDH truncates revealed that the region required for the cell wall targeting is located within the N‐terminal half of the protein. Copyright © 2003 John Wiley & Sons, Ltd.
Development of a reporter system for the yeast Schwanniomyces occidentalis: influence of DNA composition and codon usage
Authors: Janatova Ivana , Costaglioli Patricia , Wesche Jorgen , Masson Jean‐Michel , Meilhoc Eliane
Published: June 2003

In this paper we report on searching for suitable reporters to monitor gene expression and protein secretion in the amylolytic yeast Schwanniomyces occidentalis. Several potential reporter and marker genes, formerly shown to be functional in other yeasts, were cloned downstream from the homologous invertase gene (INV) promoter and their activity was followed in conditions of repression and derepression of the INV promoter. However, neither β‐glucuronidase nor β‐lactamase nor phleomycin resistance‐conferring gene, all originating from E. coli, were expressed in S. occidentalis cells to such a level to allow for monitoring of their activity. All the reporter genes tested have a higher percentage of GC (47–62%) in their DNA compared to the DNA composition of S. occidentalis genes that are more AT‐rich (36% GC). The codon usage of all the reporter genes also varies from that of 16 so far sequenced S. occidentalis genes. This suggests that an appropriate composition of DNA and a codon usage similar to S. occidentalis genes might be very important parameters for an efficient expression of a heterologous gene in Schwanniomyces occidentalis. Indeed, two genes originating from Staphylococcus aureus, with an AT‐content in their DNA similar to that of S. occidentalis, were functionally expressed in S. occidentalis cells. Both a phleomycin resistance‐conferring gene and a chloramphenicol acetyltransferase‐encoding gene thus represent suitable reporters of gene expression and protein secretion in S. occidentalis. Additionally, we show in this work that the transcription‐regulating region and the signal peptide sequence of the S. occidentalis invertase gene were efficient to direct gene expression and subsequent protein secretion in Saccharomyces cerevisiae. Copyright © 2003 John Wiley & Sons, Ltd.
Genes involved in β‐oxidation, energy metabolism and glyoxylate cycle are induced by Candida albicans during macrophage infection
Authors: Prigneau Odile , Porta Amalia , Poudrier Jacques A. , Colonna‐Romano Sergio , Noël Thierry , Maresca Bruno
Published: June 2003

The ability of intracellular pathogens to cause infection is related to their capacity to survive and grow inside macrophages or in other cell types. Candida albicans latent virulence is likely to be related to a similar mechanism of avoiding killing by specialized cells and to the resulting ability to grow in such hostile environments. Using a differential display reverse transcription polymerase chain reaction technique, we have identified seven genes induced in C. albicans during macrophage phagocytosis. Sequence analyses and database searches revealed that these cDNAs coded for proteins homologous to yeast metabolic proteins. Interestingly, four of them are putative peroxisomal proteins, and two are involved in environmental signal sensing and transduction. Among the seven genes induced by C. albicans, six represent new information that were not described in other infection models. Copyright © 2003 John Wiley & Sons, Ltd.
Construction of a set of Saccharomyces cerevisiae vectors designed for recombinational cloning
Authors: Van Mullem Vincent , Wery Maxime , De Bolle Xavier , Vandenhaute Jean
Published: June 2003

The Gateway™ technology is becoming an increasingly popular method for cloning ORFs by recombination. It allows the transfer of any ORF flanked by specific recombination sites into any vectors harbouring the corresponding sites. Here we describe the construction of a set of 20 Saccharomyces cerevisiae Gateway™ compatible vectors. These plasmids bear an URA3 or TRP1 selection marker. They are designed for expression without tag sequence or for C‐ or N‐terminal protein tagging with 3HA (haemagglutinin), 13MYC, 4TAP (tandem affinity purification) or GST (glutathione S‐transferase) epitopes. The centromeric vectors allow expression of DNA sequence in yeast under tetracycline‐regulatable promoters, while expression from the high copy vectors is driven by PGK promoter. To test their applicability, the genes encoding the RNA polymerase I subunit Rpa12p or the TFIIS transcription factor were cloned in these vectors. Their expression was demonstrated using Western blotting or complementation assays. Copyright © 2003 John Wiley & Sons, Ltd.
Bone loss following tendon laceration, repair and passive mobilization
Authors: Ditsios Konstantinos , Boyer Martin I. , Kusano Nozomu , Gelberman Richard H. , Silva Matthew J.
Published: June 2003

Little is known about the localized changes in bone mass that occur following tendon or ligament injury. Interruption of normal load transfer at the insertion site will presumably lead to a localized loss of bone, although few data exist to support this claim. To test this hypothesis, we transected the canine flexor digitorum profundus (FDP) tendon from its insertion, and either repaired it using a trans‐osseous suture technique or left it unrepaired (laceration only). Post‐operatively, forelimbs in the repair group were cast immobilized except for 10 min of daily passive mobilization rehabilitation, whereas in the laceration only group dogs were allowed full weight bearing. At 5–42 days post‐injury, we assessed bone mineral density (BMD) using pQCT and osteoclast surface by histomorphometry. We measured significant bone loss in the distal phalanx after combined FDP tendon laceration, repair, and postoperative passive mobilization, with BMD decreases of 20%, 40%, and 41% at 10, 21, and 42 days (p < 0.01). Moreover, we observed that passive mobilization and tendon laceration each contributed independently to the observed bone loss. At 42 days, BMD was reduced by 21% in bones that were not injured but were subjected to the post‐operative passive mobilization protocol, while BMD was reduced by 28% in bones subjected to tendon laceration and full weight bearing (p < 0.01). In both the passive mobilization and laceration specimens, we counted significantly increased osteoclasts after only 7–10 days, and these increases persisted through 42 days (p < 0.05). We conclude that rapid and sustained bone resorption leads to significant bone loss in the 6‐week period following flexor tendon injury and repair. This bone loss may impact healing by impeding the restoration of a strong tendon‐bone interface. © 2003 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Bedingungen der Erhaltung und Förderung von Selbständigkeit im höheren Lebensalter (SIMA) Teil XIII: Verlaufsanalyse der Gesundheit *Das interdisziplinäre Forschungsprojekt Bedingungen der Erhaltung und Förderung von Selbständigkeit im höheren Lebensalter (SIMA) des Instituts für Psychogerontologie der Friedrich-Alexander Universität Erlangen-Nürnberg wird geleitet von Prof. Dr. W. D. Oswald und Dr. R. Rupprecht, in Zusammenarbeit mit Prof. Dr. E. Lang (Carl Korth Institut), Prof. Dr. H. Baumann (Institut für Sportwissenschaft), Prof. Dr. M. Stosberg (Sozialwissenschaftliches Forschungszentrum), Dr. K. C. Steinwachs (Klinikum am Europakanal und IPG) und der Interdisziplinären Arbeitsgemeinschaft für Angewandte Gerontologie e. V. Das SIMA-Projekt wird mit Mitteln des Bundesministeriums für Familie, Senioren, Frauen und Jugend (GZ 303-1722-102/23) gefördert. Die Verantwortung für den Inhalt dieser Veröffentlichung liegt bei den Autoren.
Authors: Gaßmann Karl Günter , Lang Erich , Oswald Wolf D. , Hagen Bernd , Rupprecht Roland
Published: May 2003

Zusammenfassung: Zwischen 1991 und 1996 wurden die langfristigen Effekte der SIMA-Trainings auf den Gesundheitsstatus der Teilnehmer im Alter zwischen 75 und 93 Jahren (mittleres Alter 79.5 Jahre, 1991 N = 375) untersucht. Die Trainings wurden zwischen 1991 und 1992 in fünf voneinander unabhängigen Gruppen durchgeführt. Eine weitere Gruppe der Teilnehmer bildete die Kontrollgruppe. Die Auswertung erfolgte mit der Stichprobe jeweils aller zu einem Zeitpunkt untersuchten Teilnehmer und mit der Stichprobe der 1996 verbliebenen Teilnehmer. Der Gesundheitsstatus wurde über einen gewichteten Organfunktionsindex, den Medikamentenkonsum und die subjektive Gesundheit operationalisiert. Der gewichtete Organfunktionsindex faßt Werte aus verschiedenen Funktionsbereichen zusammen. In der Verlaufsanalyse zeigte sich, daß insbesondere die Teilnehmer eines kombinierten Gedächtnis- und Psychomotoriktrainings langfristig einen signifikant höheren Gesundheitsstatus als die Teilnehmer in der Kontrollgruppe erreichten. Diese positiven Trainingseffekte waren vor allem in den Funktionsbereichen Kreislauf - Gefäße, Bewegungsapparat und Stoffwechsel zu beobachten. Positive Ausgangswertunterschiede zugunsten der Gruppen mit einem psychomotorischen Training wurden dagegen hauptsächlich bei der subjektiven Gesundheit nachgewiesen. Frauen erreichten gegenüber Männern bessere Werte in den Funktionsbereichen Sensorium und Urogenitalsystem. Geschlechtsspezifische Wechselwirkungen der Trainings wurden nicht nachgewiesen. Die Ergebnisse zeigen, daß ein kombinierter Trainingsansatz auch im hohen Lebensalter positive Langzeiteffekte auf den Gesundheitsstatus bewirken kann.
Bedingungen der Erhaltung und Förderung von Selbständigkeit im höheren Lebensalter (SIMA) Teil XV: Verlaufsanalyse der Ernährungsqualität *Das interdisziplinäre Forschungsprojekt Bedingungen der Erhaltung und Förderung von Selbständigkeit im höheren Lebensalter (SIMA) des Instituts für Psychogerontologie der Friedrich-Alexander Universität Erlangen-Nürnberg wird geleitet von Prof. Dr. W. D. Oswald und Dr. R. Rupprecht, in Zusammenarbeit mit Prof. Dr. E. Lang (Carl Korth Institut), Prof. Dr. H. Baumann (Institut für Sportwissenschaft), Prof. Dr. M. Stosberg (Sozialwissenschaftliches Forschungszentrum), Dr. K. C. Steinwachs (Klinikum am Europakanal und IPG) und der Interdisziplinären Arbeitsgemeinschaft für Angewandte Gerontologie e. V. Das SIMA-Projekt wird mit Mitteln des Bundesministeriums für Familie, Senioren, Frauen und Jugend (GZ 303-1722-102/23) gefördert. Die Verantwortung für den Inhalt dieser Veröffentlichung liegt bei den Autoren.
Authors: Hagen Bernd , Sommer Maria , Oswald Wolf D. , Rupprecht Roland
Published: May 2003

Zusammenfassung: Zwischen 1991 und 1996 wurden die langfristigen Effekte der SIMA-Trainings auf die Ernährungsqualität der Teilnehmer im Alter zwischen 75 und 93 Jahren (1991 mittleres Alter 79.5 Jahre) untersucht. Die Auswertung erfolgte mit der Stichprobe jeweils aller zu einem Zeitpunkt untersuchten Teilnehmer und mit der Stichprobe der 1996 verbliebenen Teilnehmer. Im Rahmen eines Kompetenztrainings wurde Wissen über die Ernährung im Alter vermittelt. Die über einen Food-Frequency-Fragebogen erhobenen Verzehrshäufigkeiten für die Lebensmittelbereiche Vollkornprodukte, Gemüse, Obst, Milch und Milchprodukte, Fleisch, Wurst und Eier, Fisch, Kartoffeln sowie die Trinkmenge wurden mit Hilfe der Empfehlungen der Deutschen Gesellschaft für Ernährung (DGE) bewertet. Gemessen an den DGE-Empfehlungen waren unter Einschluß aller Lebensmittelbereiche zwischen 16.5 % (1991) und 25.1 % (1996) der Teilnehmer gut ernährt, bei Beschränkung auf die Bereiche Vollkornprodukte, Gemüse, Obst, Milch und Milchprodukte zwischen 60.8 % (1991) und 60.9 % (1996). Im Vergleich zu der Kontrollgruppe konnten keine bedeutsamen langfristigen Treatmenteffekte des Kompetenztrainings oder der übrigen Trainingsprogramme nachgewiesen werden. Ebenfalls zeigten sich keine bedeutsamen Zusammenhänge zwischen der Ernährungsqualität und der Selbständigkeit, dem kognitiven und psychopathologischen Status oder der Gesundheit der Teilnehmer. Zusammenhänge des Ausgangswertes mit den Nachfolgewerten der Ernährungsqualität zwischen φ = .28 und φ = .44 (1996) bestätigten dagegen ein sehr konstantes Ernährungsverhalten der Teilnehmer. Die Ergebnisse verweisen auch auf die Bedeutung indi vidueller und sozialer Aspekte der Ernährung im Alter.
Bedingungen der Erhaltung und Förderung von Selbständigkeit im höheren Lebensalter (SIMA) Teil XVI: Verlaufsanalyse der Befindlichkeit und des subjektiven Alters *Das interdisziplinäre Forschungsprojekt Bedingungen der Erhaltung und Förderung von Selbständigkeit im höheren Lebensalter (SIMA) des Instituts für Psychogerontologie der Friedrich-Alexander Universität Erlangen-Nürnberg wird geleitet von Prof. Dr. W. D. Oswald und Dr. R. Rupprecht, in Zusammenarbeit mit Prof. Dr. E. Lang (Carl Korth Institut), Prof. Dr. H. Baumann (Institut für Sportwissenschaft), Prof. Dr. M. Stosberg (Sozialwissenschaftliches Forschungszentrum), Dr. K. C. Steinwachs (Klinikum am Europakanal und IPG) und der Interdisziplinären Arbeitsgemeinschaft für Angewandte Gerontologie e. V. Das SIMA-Projekt wird mit Mitteln des Bundesministeriums für Familie, Senioren, Frauen und Jugend (GZ 303-1722-102/23) gefördert. Die Verantwortung für den Inhalt dieser Veröffentlichung liegt bei den Autoren.
Authors: Hagen Bernd , Fricke Christine , Oswald Wolf D. , Rupprecht Roland
Published: May 2003

Zusammenfassung: Zwischen 1991 und 1996 wurden die langfristigen Effekte der SIMA-Trainings auf die Befindlichkeit und das subjektive Alter der Teilnehmer im Alter zwischen 75 und 93 Jahren (1991 mittleres Alter 79.5 Jahre) untersucht. Während die Befindlichkeit über drei Selbsteinschätzungsskalen erhoben wurde, diente das subjektive Alter als ein Indikator des selbsteingeschätzten aktuellen körperlichen und geistigen Alters. Die Auswertung erfolgte mit der Stichprobe jeweils aller zu einem Zeitpunkt untersuchten Teilnehmer und mit der Stichprobe der 1996 verbliebenen Teilnehmer. 1991 gaben 85.1 % der Teilnehmer an, mit ihrem bisherigen Leben zufrieden zu sein. Die Teilnehmer schätzten bei Studienbeginn ihr subjektives Alter durchschnittlich um 11.6 Jahre niedriger als ihr kalendarisches Alter ein. Bis 1996 konnten insbesondere in der Gedächtnis- und Psychomotoriktrainingsgruppe eine positivere Befindlichkeit sowie in der Kompetenz- und Psychomotoriktrainingsgruppe eine niedrigeres subjektives Alter nachgewiesen werden. Diese Unterschiede zur Kontrollgruppe bestanden jedoch bereits bei Studienbeginn. In den übrigen Trainingsgruppen zeigten sich keine systematischen Langzeiteffekte. Unter Einschluß der Kovariate Ausgangswert wurden für keine der fünf Treatmentgruppen bedeutsame langfristige Trainingseffekte nachgewiesen. Bedeutsame Zusammenhänge fanden sich zwischen einer positiven Befindlichkeit und einer geringen depressiven Symptomatik (r = .80), einem guten Gesundheitsstatus (r = .53) einer hohen Selbständigkeit (r = .52) sowie einem niedrigen subjektiven Alter (r = .44). Die Ergebnisse zeigen, daß die bereits hohen Ausgangswerte der Befindlichkeit sowie die niedrigen des subjektiven Alters durch die Trainingsprogramme langfristig nicht mehr bedeutsam verändert werden konnten. Andererseits deuten die hohen Korrelationen auf wichtige, treatmentgruppenunspezifische Einflußfaktoren der Befindlichkeit und des subjektiven Alters hin.
Korrelate altersbezogener Leistung in typischen Arbeitsgedächtnisspannentests
Authors: Kliegel Matthias , Zeintl Melanie , Martin Mike , Kopp Ute A.
Published: May 2003

Zusammenfassung: In der neueren gerontologischen Kognitionsforschung haben sich wiederholt Alterseffekte bezüglich der Leistung in verschiedenen Arbeitsgedächtnisspannentests bestätigt. Bislang ist jedoch unklar, welche Rolle nicht-exekutive und exekutive Prozesse in diesen Alterseffekten spielen. Zur ersten Annäherung an diese Fragestellung wurden in der vorliegenden Studie 20 jüngere (M = 26 Jahre, SD = 7.14) und 21 ältere Erwachsene (M = 71 Jahre, SD = 5.87) in ihrer Leistung in zwei typischen Arbeitsgedächtnisspannentests (“Zahlen nachsprechen rückwärts”, Operation Span Aufgabe) untersucht. Außerdem wurden als mögliche Prädiktoren für nicht-exekutive Prozesse die Kurzzeitgedächtnisspanne und die tonische Aufmerksamkeit sowie für exekutive Prozesse die inhibitorische Kontrollleistung erhoben. Die Ergebnisse zeigen signifikante Altersdifferenzen in beiden Arbeitsgedächtnisspannentests. Zusätzlich ergeben hierarchische Regressionsanalysen, dass im Test “Zahlen nachsprechen rückwärts” nicht-exekutive Prozesse alleine, in der Operation Span Aufgabe dagegen eine Kombination aus nicht-exekutiven und exekutiven Prozessen die gefundene altersbezogene Varianz erklären können. Insgesamt deuten die Ergebnisse darauf hin, dass die beiden verwendeten Arbeitsgedächtnisspannentests schwerpunktmäßig mit unterschiedlichen kognitiven Prozessen zusammenhängen und somit in Diagnostik wie Grundlagenforschung nicht beliebig austauschbar angewandt werden sollten.
Bedingungen der Erhaltung und Förderung von Selbst- ständigkeit im höheren Lebensalter (SIMA)
Authors: Rupprecht Roland , Oswald Wolf D. , Hagen Bernd , Steinwachs Klaus-Christian
Published: May 2003

Zusammenfassung: Im Rahmen der 1991 begonnenen Längsschnittstudie SIMA wurde die Entwicklung einer demenziellen Erkrankung unter den Teilnehmern zwischen 1991 und 1998 verfolgt. Für insgesamt 340 der ursprünglich 375 Teilnehmer ließ sich feststellen, ob bei ihnen bis Ende 1998 eine demenzielle Erkrankung aufgetreten ist. Die Teilnehmer lebten bei Studienbeginn selbstständig und waren zwischen 75 und 93 Jahren bzw. im Mittel 79.5 (± 3.5) Jahre alt. Unter Einschluss der inzwischen verstorbenen Teilnehmer erkrankten 46 Teilnehmer an einer Demenz. Weitere 28 Teilnehmer litten an einer leichten kognitiven Beeinträchtigung. In multivariaten Risikoanalysen (Cox Regression) wurden signifikante medizinische und psychologische Risikofaktoren bestätigt, wobei es sich auf der medizinischen Seite jeweils um Diagnosen, auf der psychologischen Seite um Leistungen unter dem Median der Gesamtgruppe handelte. Als die bedeutendsten Demenzrisiken ließen sich verschiedene geringe kognitive Leistungen und das Auftreten einer Frühsymptomatik erkennen. Die Befunde der SIMA-Studie zeigen, dass weder Defizite in einem einzelnen kognitiven Leistungsbereich noch einzelne typische Erkrankungen die ausschließlichen Demenzrisiken im höheren Lebensalter darstellen. Die gleichzeitige Bedeutung insbesondere einer Reihe kognitiver Risikofaktoren dokumentiert zudem, dass der Beginn einer Demenz möglicherweise durch ein multimodales Trainingsprogramm erfolgreich hinausgezögert werden kann.
Der FRAG als computergestütztes diagnostisches Verfahren zur Erfassung der visuellen Worterkennung
Authors: Nuerk Hans-Christoph , Graf Ralf , Boecker Maren , Gauggel Siegfried , Jacobs Arthur M.
Published: May 2003

Zusammenfassung: Der computergestützte Wortfragmentationstest FRAG wird in der kognitiven Psychologie zur modellgeleiteten Untersuchung perzeptuell-attentiver wie auch lexikalischer Prozesse verwendet. In der vorliegenden Studie untersuchen wir die klinische Brauchbarkeit und die differentielle Validität des FRAG bei einer Stichprobe von hirngeschädigten Patienten. Die Ergebnisse deuten darauf hin, dass der FRAG in der Lage ist, zwischen aphasischen und nicht-aphasischen Patienten auch individuell bei guter Reliabilität und Validität zu unterscheiden. Wie erwartet, zeigen Aphasiker beim Erkennen von Wörtern gegenüber nicht-aphasischen Patienten und studentischen Versuchspersonen eine verringerte Lesegeschwindigkeit und -genauigkeit. Eine funktionelle Analyse des Leseprozesses deutet ferner auf spezifische Lesedefizite bei Aphasikern hin. Insgesamt könnte der FRAG eine Ergänzung zu anderen Lesetests im Hinblick auf eine funktionelle, modellgeleitete Diagnose von Lesestörungen darstellen. Allerdings müssen vor einem routinemäßigen Einsatz noch umfangreichere Validierungs- und Normierungsstudien durchgeführt werden.
Discriminating Between Task-Relevant and Task-Irrelevant Stimuli
Authors: Neumann David L. , Lipp Ottmar V. , Siddle David A.T.
Published: June 2003

Abstract The effect that the difficulty of the discrimination between task-relevant and task-irrelevant stimuli has on the relationship between skin conductance orienting and secondary task reaction time (RT) was examined. Participants (N = 72) counted the number of longer-than-usual presentations of one shape (task-relevant) and ignored presentations of another shape (task-irrelevant). The difficulty of discriminating between the two shapes varied across three groups (low, medium, and high difficulty). Simultaneous with the primary counting task, participants performed a secondary RT task to acoustic probes presented 50, 150, and 2000 ms following shape onset. Skin conductance orienting was larger, and secondary RT at the 2000 ms probe position was slower during task-relevant shapes than during task-irrelevant shapes in the low-difficulty group. This difference declined as the discrimination difficulty was increased, such that there was no difference in the high-difficulty group. Secondary RT was slower during task-irrelevant shapes than during task-relevant shapes only in the medium-difficulty group - and only at the 150 ms probe position in the first half of the experiment. The close relationship between autonomic orienting and secondary RT at the 2000 ms probe position suggests that orienting reflects the resource allocation that results from the number of matching features between a stimulus input and a mental representation primed as significant.
Mirror Tracing and the Provocation of Vascular-Dominant Reaction Pattern Through Heightened Attention
Authors: Sawada Yukihiro , Nagano Yuichiro , Tanaka Gohichi
Published: June 2003

Abstract After a hint from Lang et al.'s (1997) defence cascade, researchers considered cognitive process experienced when encountering mental stress to be composed of four elements: (serially) first attention (Attent), second unpleasant affect (UnplAff) and sometimes pleasant affect (PlAff), and third cognitive coping (CogCop). The present study investigates the effect of each cognitive element on the provocation of the well-known vascular-dominant reaction pattern during mirror tracing: elevation of mean blood pressure mainly because of increases in total peripheral resistance. Twenty-four male students first underwent four computer-simulated mirror-tracing practices of 3 min each, then a 7 min adaptation followed by a 3 min baseline, and further four kinds of actual mirror tracing trials (Attent, UnplAff, PlAff, and CogCop) of 3 min each. Results on the cardiovascular measures indicated that every mirror-tracing trial indisputably provoked the vascular-dominant reaction pattern. An alpha-adrenergic vascular sympathetic activation was heightened. Self-report measures on the four cognitive elements suggested that heightened Attent seemed to contribute to provoking the reaction pattern. Although the UnplAff and PlAff trials had an active coping feature in a narrow sense, they could not provoke the cardiac-dominant reaction pattern. Differences in task difficulty among the mirror tracings could not explain the results. The implications of these results are discussed in order to better understand cardiovascular hemodynamics during mental stress.