bluuebunny/crossref_metadata_2025 huggingface dataset:
DATA MINING VIA MULTIPLE CRITERIA LINEAR PROGRAMMING: APPLICATIONS IN CREDIT CARD PORTFOLIO MANAGEMENT
Authors: SHI YONG , PENG YI , XU WEIXUAN , TANG XIAOWO
Published: May 2003

Data mining becomes a cutting-edge information technology tool in today's competitive business world. It helps the company discover previously unknown, valid, and actionable information from various and large databases for crucial business decisions. This paper provides a promising approach of data mining to classify the credit cardholders' behavior through multiple criteria linear programming. After reviewing the history of linear discriminant analyses, we will describe first a model for classifying two-group (e.g. bad or good) credit cardholder behaviors, and then a three-group (e.g. bad, normal, or good) credit model. Besides the discussion of the modeling structure, we will utilize the well-known commercial software package SAS to implement this technology by using a real-life credit card data warehouse. A number of potential business and financial applications will be finally summarized.
CLOSE IMITATION OF EXPERT KNOWLEDGE: THE PROBLEM AND METHODS
Authors: LARICHEV OLEG I.
Published: May 2003

The problems of the nature of expertise and the possibility to create a copy of expert knowledge in the computer are the main themes for the paper. In the first part of this paper, a short survey of existing knowledge about expert behavior is given. The new method for the construction of exact copy of expert knowledge-CONSER is described. The utilization of new method gives new information about the striking ability of expert to recognize and classify the situations on the basis of their knowledge.
INTRODUCTION TO OPPORTUNITY CYBERNETICS AND DECISION-HARMONIZING THEORY IN ENTERPRISES' MULTIPLE VENTURE MANAGEMENT
Authors: GE JIALI , ZHANG HONGMIN
Published: May 2003

This paper introduces a new concept of risk management for modern enterprises so-called opportunity cybernetics and decision-harmonizing theory. This theory was developed based on new challenges of which the enterprises face in the market, such as reverse correlativity, bubbled falsehood, virtual exchange, disorder chaos and unstable variation. The objective of opportunity cybernetics is to achieve the optimal combined profit for the enterprises with multiple venture management through a dynamic modeling control. The successful enterprises should maintain a harmony of chaos in uncertain business events and seek a compromise solution in competitive market. The paper also uses a giant petroleum company to show how to implement the opportunity cybernetics and decision-harmonizing theory in the real world.
SADDLE PAIRS OF VECTOR-VALUED FUNCTIONS AND CONE-EXTREME POINTS
Authors: SALUKVADZE MINDIA E. , TOPCHISHVILI ALEXANDER L. , MAISURADZE VILHELM G.
Published: May 2003

In this paper, different types of saddle pairs of vector-valued functions are investigated. Main properties of these pairs are examined. Structure of images of saddle pair sets is found and these images are constructed by means of cone extreme points in an explicit way as well. The obtained results provide possibility to construct dual problems in general cases of multiple objective problems and to investigate how to solve them using saddle pairs approach.
RULES DETECTING AND RULES-DATA MUTUAL ENHANCEMENT BASED ON FACTORS SPACE THEORY
Authors: WANG PEI-ZHUANG , JIANG ALEX
Published: May 2003

This paper presents a new method of rules detecting about exploring hidden rules from a given knowledge base. The expended rule set forms a lattice that can be generated by the core. Not only does this method produce detecting rules, but also enhance data integrity and completeness. In addition, this paper introduces the concept of rules-data mutual enhancement, which can detect the ultimate relationship between data and rules with the utilization of two types of information resources: databases and knowledge bases. As a result, this paper makes initial endeavors to combine those two quite separated fields to promote the development of information technology.
INFERENCE IN BAYESIAN NETWORKS: THE ROLE OF CONTEXT-SPECIFIC INDEPENDENCE
Authors: ZHANG NEVIN L.
Published: May 2003

Three kinds of independence are of interest in the context of Bayesian networks, namely conditional independence, independence of causal influence, and context-specific independence. It is well-known that conditional independence enables one to factorize a joint probability into a list of conditional probabilities and thereby renders inference feasible. It has recently been shown that independence of causal influence leads to further factorizations of some of the conditional probabilities and consequently makes inference faster. This paper studies context-specific independence. We show that context-specific independence can be used to further decompose some of the conditional probabilities. We present an inference algorithm that takes advantage of the decompositions and provide, for the first time, empirical evidence that demonstrates the computational benefits of exploiting context-specific independence.
IMPROVEMENT ON BEHAVIOR SCORES BY DUAL-MODEL SCORING SYSTEM
Authors: LIN YACHEN
Published: May 2003

In credit risk management, the on-line analytical process has been accepted by most credit card issuers. The major tools used in such an OLAP are statistics and neural networks. Through a designed algorithm, the OLAP generates scores for each account or for each customer which depends on the level of the processing. Generally speaking, logistic regressions and feed-forward networks are the major players in OLAP of this field and usually are used separately. This paper discusses an approach — Dual-Model Scoring System — to combine these two major players and use them together in the credit scoring. Primarily, the classification problem for two classes are considered. By the Bayesian rule, the objective function of classification can be reduced to estimate the Bayesian posterior probability. Such a probability is estimated by using the MLE approach in logistic regressions and the Two-Stage (Gibbs) learning algorithm3 in feed-forward networks. The motivation of the proposal comes from the following two considerations: (1) Both logistic regression and neural networks have their advantages and disadvantages and the combined of these two can enhance their predictive ability and offset their weakness. (2) To reduce the false positive rate in the decision region. Besides the discussion of the architecture design of Dual-Model Scoring System, the paper has demonstrated the power of the present proposal in a real data set.
FUZZY REGRESSION FOR SEASONAL TIME SERIES ANALYSIS
Authors: TSAUR RUEY-CHYN , WANG HSIAO-FAN , O.-YANG JIA-CHI
Published: May 2003

Fuzzy regression model is an alternative to evaluate the relation between independent variables and dependent variable among the forecasting models when the data are not sufficient to identify the relation. Such phenomenon is significant especially for seasonal variation data for which large amount of data are required to show the pattern. However, few researches have been done on this issue. Because of its increasing importance in industries, in this study, we propose a method of applying fuzzy regression model for this purpose. By using two independent variables of preceding periodical data and index of time, the developed model not only shows the pattern of the seasonal variation, but also the yearly trend. From the results of the illustration, the average forecasting error is below 1.85% which, in comparison to the most commonly used Quadratic Trend Analysis of 2.91% and the Double Exponential Smoothing Model of 4.29%, has a better performance.
INFORMATION DIFFUSION TECHNIQUES AND SMALL-SAMPLE PROBLEM
Authors: HUANG CHONGFU
Published: May 2003

Strong interests in the small-sample problem have been given towards for establishing several information diffusion techniques for pattern recognition. In this paper, we review and formalize three techniques: the soft histogram, the self-study discrete regression, and the interior-outer-set model. To promote the development of this area, in this paper we suggest two open topics: the anti-accuracy principle and the digital image compression technique based on the fuzzy if-then rules extracted by using information matrix technique.
MULTIOBJECTIVE DECISION SUPPORT IN IT-RISK MANAGEMENT
Authors: STRAUSS CHRISTINE , STUMMER CHRISTIAN
Published: May 2003

Security issues in information management are increasingly moving towards the centre of corporate interests. This paper presents a multiobjective modelling approach that interactively assists IT managers in their attempts to reduce a given risk by evaluating and selecting portfolios (i.e. bundles) of security measures. The proposed multi-step procedure identifies attractive portfolio candidates and finally establishes the "best" one with respect to the decision-maker's preferences. Our model and its possible application are demonstrated by means of a numerical example based on real-world data that evaluates the risk of hacking faced by a Local Area Network in an academic environment.
MAKING PUBLIC POLICY DECISIONS USING A WEB-BASED MULTI-CRITERIA ELECTORAL SYSTEM (MCES)
Authors: ZAHIR SAJJAD
Published: May 2003

A detailed model for designing an online Multi-Criteria Electoral System (MCES) is presented. Such a system is based on emerging technology and the Analytic Hierarchy Process (AHP). It deals with the intensity of preferences in contrast with traditional "yes-no" votes. Our objective is to minimize the imperfections of traditional voting systems and bring about electoral reform. A prototype Web-based system is developed and then used to analyze a real public policy issue. We also explore the practical implications of such a system in the context of a few other scenarios.
A MULTI-ENGINE TRANSLATION APPROACH TO MACHINE TRANSLATION
Authors: REN FUJI , SHI HONGCHI
Published: May 2003

One of the most difficult problems in dialogue machine translation is to correctly translate irregular expressions in natural conversations such as ungrammatical, incomplete, or ill-formed sentences. However, most existing machine translation systems reject utterances including irregular expressions. In this paper, we present a dialogue machine translation approach based on a cooperative distributed natural language processing model to attack the complex machine translation problem. In this approach, different types of translation processors are used in the analysis of the original language and the generation of the target language. The idea of combining multiple machine translation engines provides a new effective way to increase the success rate and quality of dialogue machine translation. A dialogue machine translation using multiple processors (DMTMP) system has been built using the following machine translation processors: (i) Robust Parser based Translation Processor, (ii) Example based Translation Processor, (iii) Family Modal based Translation Processor, and (iv) Super Function based Translation Processor. DMTMP is used in a practical machine translation environment called SWKJC. Experiments show that the approach presented in this paper is effective in implementation of robust dialogue machine translation systems.
DECISION INTELLIGENCE: PREDICTING PEOPLE'S POLICYMAKING STYLES
Authors: WYATT RAY
Published: May 2003

The driving force behind this paper is a generic, advice-giving computer program. It collects knowledge about its past users' policymaking behavior. We concentrate here on analyzing such knowledge. That is, we document which policy-evaluation criteria are the most important for each type of person — their "policymaking style". Such knowledge allows us to predict what people's favored policies will be. It also enables us to estimate where, within the community, any particular policy will find its strongest supporters. Such anticipation — "decision intelligence", helps any profession to better empathize with the needs of its clientele.
KNOWLEDGE OF ENTERPRISE: KNOWLEDGE MANAGEMENT OR KNOWLEDGE TECHNOLOGY?
Authors: ZELENY MILAN
Published: May 2003

Knowledge Technology (KT) is an important new development, extending and ultimately replacing IT. Meaningful and substantial Knowledge Management (KM) is crucially dependent on a useful and operational definition of knowledge. Such notion of knowledge must be clearly differentiated from so called "explicit (or codified) knowledge", i.e. from information. Information, in any form or shape, is not knowledge. While information is a symbolic description of action, knowledge is action itself. The understanding that knowing is doing and doing is knowing comes from the Western philosophical tradition of pragmatism, exemplified by Dewey, Lewis and Polanyi. In this paper, we look at knowledge as a manifest ability of purposeful coordination of action and redefine the purpose of knowledge management as turning information (description) into knowledge (action) and not vice versa. While there can be an information overload, there is never any "knowledge overload".
GEOMETRIC PHASES AND TOPOLOGICAL QUANTUM COMPUTATION
Authors: VEDRAL VLATKO
Published: May 2003

In the first part of this review we introduce the basics theory behind geometric phases and emphasize their importance in quantum theory. The subject is presented in a general way so as to illustrate its wide applicability, but we also introduce a number of examples that will help the reader understand the basic issues involved. In the second part we show how to perform a universal quantum computation using only geometric effects appearing in quantum phases. It is then finally discussed how this geometric way of performing quantum gates can lead to a stable, large scale, intrinsically fault-tolerant quantum computer.
ON THE ROLE OF LOCALITY CONDITION IN BELL'S THEOREM
Authors: RAZMI HABIBOLLAH
Published: May 2003

For a special stochastic realistic model in certain spin-correlation experiments and without imposing the locality condition, an inequality is found. Then, it is shown that quantum theory is able (is possible) to violate this inequality. This shows that, irrespective of the locality condition, the quantum entanglement of the spin singlet-state is the reason for the violation of Bell's inequality in Bell's theorem.
SEPARABILITY OF RANK TWO QUANTUM STATES ON MULTIPLE QUANTUM SPACES WITH DIFFERENT DIMENSIONS
Authors: FEI SHAO-MING , GAO XIU-HONG , WANG XIAO-HONG , WANG ZHI-XI , WU KE
Published: May 2003

We consider the separability of rank two quantum states on multiple quantum spaces with different dimensions. The sufficient and necessary conditions for separability of these multiparty quantum states are explicitly presented. A nonseparability inequality is also given for the case where one of the eigenvectors corresponding to nonzero eigenvalues of the density matrix is maximally entangled.
THE HESS-PHILIPP MODEL IS NON-LOCAL
Authors: APPLEBY D. M.
Published: May 2003

Hess and Philipp have constructed what, they claim, is a local hidden variables model reproducing the empirical predictions of quantum mechanics. In this paper explicit expressions for the conditional probabilities for the outcomes of the measurements at the two detectors are calculated. These expressions provide a conclusive demonstration of the falsity of the authors' claim. The authors give two different accounts of their model. The published version omits a crucial detail. As a result it disagrees with quantum mechanics. It also violates signal locality. The unpublished version agrees with quantum mechanics. However, it violates the condition of parameter independence, as Myrvold has previously shown.
RELATIVISTIC EINSTEIN-PODOLSKY-ROSEN CORRELATION AND BELL'S INEQUALITY
Authors: TERASHIMA HIROAKI , UEDA MASAHITO
Published: May 2003

We formulate the Einstein-Podolsky-Rosen (EPR) gedankenexperiment within the framework of relativistic quantum theory to analyze a situation in which measurements are performed by moving observers. We point out that under certain conditions the perfect anti-correlation of an EPR pair of spins in the same direction deteriorates in the moving observers' frame due to the Wigner rotation, and show that the degree of the violation of Bell's inequality prima facie decreases with increasing velocity of the observers if the directions of the measurement are fixed. However, this does not imply a breakdown of non-local correlation since the perfect anti-correlation is maintained in appropriately chosen different directions. When considering moving frames we must take account of this relativistic effect on the EPR correlation and on the violation of Bell's inequality for quantum communication.
ON THE EQUIVALENCE OF THE CH AND CHSH INEQUALITIES FOR TWO THREE-LEVEL SYSTEMS
Authors: CERECEDA JOSÉ L.
Published: May 2003

In this paper we show a Clauser-Horne (CH) inequality for two three-level quantum systems or qutrits, alternative to the CH inequality given by Kaszlikowski et al. [Phys. Rev. A65, 032118 (2002)]. In contrast to this latter CH inequality, the new one is shown to be equivalent to the Clauser-Horne-Shimony-Holt (CHSH) inequality for two qutrits given by Collins et al. [Phys. Rev. Lett. 88, 040404 (2002)]. Both the CH and CHSH inequalities exhibit the strongest resistance to noise for a nonmaximally entangled state for the case of two von Neumann measurements per site, as first shown by Acin et al. [Phys. Rev. A65, 052325 (2002)]. This equivalence, however, breaks down when one takes into account the less-than-perfect quantum efficiency of detectors. Indeed, for the noiseless case, the threshold quantum efficiency above which there is no local and realistic description of the experiment for the optimal choice of measurements is found to be [Formula: see text] for the CH inequality, whereas it is equal to [Formula: see text] for the CHSH inequality.
METHOD FOR IMPLEMENTATION OF UNIVERSAL QUANTUM LOGIC GATES IN A SCALABLE ISING SPIN QUANTUM COMPUTER
Authors: BERMAN G. P. , KAMENEV D. I. , KASSMAN R. B. , PINEDA C. , TSIFRINOVICH V. I.
Published: May 2003

We present protocols for implementation of universal quantum gates on an arbitrary superposition of quantum states in a scalable solid-state Ising spin quantum computer. The spin chain is composed of identical spins 1/2 with the Ising interaction between the neighboring spins. The selective excitations of the spins are provided by the gradient of the external magnetic field. The protocols are built of rectangular radio-frequency pulses. Since the wavelength of the radio-frequency pulses is much larger than the distance between the spins, each pulse affects all spins in the chain and introduces the phase and probability errors, which occur even without the influence of the environment. These errors caused by the unwanted transitions are minimized and computed numerically.
APPLYING QUANTUM SEARCH TO AUTOMATED TEST PATTERN GENERATION FOR VLSI CIRCUITS
Authors: SINGH AMARDEEP , SINGH SARBJEET
Published: May 2003

This paper presents a quantum search algorithm for Automated Test Pattern Generation (ATPG) of VLSI circuits. For given digital circuits, a neural network is created that represents the digital gates with their interconnections as neurons. This neural network is characterized by an energy function E, which is the mathematics representation of neural network. The solution of the energy function gives us the test vector. The test vector is a combination of input values of digital circuits that detects a particular fault. In this paper, specific aspects of quantum theory like superposition and quantum parallelism are applied to find the solution of this energy function. The algorithm developed is so efficient that it requires only [Formula: see text] (where N is the total number of vectors) iterations to find the desired test vector whereas in classical computing, it takes N/2 iterations. At the end, a comparison is made between exhaustive, simulated annealing and quantum based techniques. Experimental results show that the quantum search algorithms are more efficient than classical algorithms and can be applied with more efficiency.
GEOMETRIC PHASES FOR MIXED STATES DURING UNITARY AND NON-UNITARY EVOLUTIONS
Authors: PATI ARUN K.
Published: May 2003

Mixed states typically arise when quantum systems interact with the outside world. Evolution of open quantum systems in general are described by quantum operations which are represented by completely positive maps. We elucidate the notion of geometric phase for a quantum system described by a mixed state undergoing unitary evolution and non-unitary evolutions. We discuss parallel transport condition for mixed states both in the case of unitary maps and completely positive maps. We find that the relative phase shift of a system not only depends on the state of the system, but also depends on the initial state of the ancilla with which it might have interacted in the past. The geometric phase change during a sequence of quantum operations is shown to be non-additive in nature. This property can attribute a "memory" to a quantum channel. We explore these ideas and illustrate them with simple examples.
Applications of the Saccharomyces cerevisiae Flp-FRT System in Bacterial Genetics
Authors: Schweizer Herbert P.
Published: May 2003

The Flp-FRT site-specific recombinationsystem from Saccharomyces cerevisiae is a powerful and efficient tool for high-throughput genetic analysis of bacteria in the postgenomic era. This review highlights the features of the Flp-FRT system, describes current bacterial genetic methods incorporating this technology and, finally, suggests potential future uses of this system. In combination with improved allele replacement methods, recyclable FRT mutagenesis cassettes, whose antibiotic resistance markers can be excised from the chromosome in vivo, are useful for the rapid construction of multiple, unmarked mutations in the same chromosome, and thus aid in the generation of live vaccine strains or food-safe bacteria. The high-specificity of the Flp-FRT system makes it also applicable for manipulation of whole genomes, including in vivo cloning of large genomic segments. Integration-proficient vectors, from which antibiotic resistance markers and replication functions can be evicted after integration of the desired sequences into the chromosome, are useful for the construction of strains destined for environmental release, e.g. strains used as biosensors or for bioremediation. Although the Flp-FRT system is extremely efficient and easy to use, its true potential in bacterial genetics has not yet been fully exploited. On the contrary, in many instances this technology is probably greatly underutilized, especially in gram-positive bacteria.
Maize Activator (Ac) Transposase (TPase) Is Expressed in Saccharomyces cerevisiae from a Genomic Clone
Authors: MacRae Amy F.
Published: May 2003

The maize Activator (Ac) transposase (TPase) was expressed as a Histidine (His)-tagged protein in Saccharomyces cerevisiae from a full length genomic clone. Expression was demonstrated via the highly specific nickel-coated Elisa plate method, using an anti-His antibody and 2 separate anti-Ac TPase antibodies, to Ac residues 103–465 and 189–807. Ac TPase expression in Saccharomyces is important for two reasons: (a) because the expression from a genomic clone herein permits the future study of RNA splicing mechanisms in common between maize and yeast systems, and (b) because a yeast system can easily be used for demonstrating complementation of function. Thus, such transformed yeast systems could be used in future, to experimentally test whether Ac TPase could complement various yeast mutations. Specifically, Ac TPase may be able to complement (i.e. provide the same function) to yeast transcription factor mutants or to genes mutated in other essential yeast functions. If confirmed, this would lend support to Barbara McClintock’s hypothesis that transposable elements can serve as ‘controlling elements’ within the genome, by their ability to supplement other essential genes’ functions, as needed. Work herein is contrasted with existing studies on Ac in yeast.
Nucleotide Sequence Analysis of the Sialyltransferase Genes of Meningococcal Serogroups B, C, Y and W135
Authors: Lewis C. , Diggle M.A. , Clarke S.C.
Published: May 2003

A rapid method for serogrouping meningococci is essential for the characterization of phenotypically non-groupable meningococcal isolates and clinical samples, particularly for public health management purposes. The Scottish Meningococcus and Pneumococcus Reference Laboratory (SMPRL) provides serogrouping results of meningococcal isolates and clinical samples using a PCR assay which detects restriction fragment length polymorphisms in meningococcal serogroups B, C, Y and W135. Although this PCR system was invaluable when first introduced, it has several drawbacks and lacks the required sensitivity for detecting DNA in clinical samples. Due to the recent introduction of the meningococcal group C conjugate vaccine and an impending group B vaccine, a more robust and informative method for serogroup determination is required. A protocol was devised allowing PCR amplification of the siaD gene of serogroup B, C, Y and W135 meningococci. This system was multiplexed and allowed serogroup differentiation between serogroups B and C and also between B/C and Y/W135 by product size analysis. A nested stage was incorporated into the system for enhanced detection of meningococci in clinical samples, and finally a sequencing protocol was designed allowing detection of any nucleotide changes within the siaD gene. This system allows rapid serogrouping results for use within an agarose gel system as well as more informative results when used for sequencing within the siaD gene.
Regulation of fruA Expression during Vegetative Growth and Development of Myxococcus xanthus
Authors: Horiuchi Takayuki , Akiyama Takuya , Inouye Sumiko , Komano Teruya
Published: May 2003

Expression of the fruA gene, encoding a putative transcription factor essential for fruiting body formation of Myxococcus xanthus, is specifically activated during development. In the present study, we have analyzed the mechanism of the transcriptional regulation of fruA expression. From gel retardation and footprinting assays using various fruA regulatory regions as probes and competitors, a protein designated factor X was found to specifically bind to a sequence (xbs) located downstream of the transcription-initiation site (+78 to +94) of the fruA gene. Factor X activity was present during vegetative growth and decreased during early development. Analysis of promoter activities of various segments of the fruA regulatory region using the lacZ reporter gene in vivo indicated that a DNA segment extending 45-bp upstream from the transcription-initiation site was required for developmentally regulated fruA expression at a low level. In addition, cis-acting regulatory regions located upstream and downstream of the fruA promoter region and including C-box and xbs, were found to be involved in regulation of fruA expression during development. When inserted into the vegA gene, the xbs element inhibited vegA expression during vegetative growth. Together with previously reported results, our studies reveal that fruA expression is regulated by both positive and negative mechanisms during the M. xanthus life cycle.
Comparison of the Changes in Global Gene Expression of Escherichia coli Induced by Four Bactericidal Agents
Authors: Shaw Karen Joy , Miller Nancy , Liu Xuejun , Lerner Dmitri , Wan Jackson , Bittner Anton , Morrow Brian J.
Published: May 2003

DNA microarrays provide a global view of the physiological state of the cell by parallel analysis of the expression levels of all the genes in an organism. The effects of four bactericidal agents on the expression pattern of Escherichia coli MG1655 were assessed. Compounds were chosen on the basis of their different mechanisms of action and included inhibitors of DNA replication and recombination, translation, transcription and cell wall biosynthesis. The addition of rifampin resulted in increased expression of the target, rpoB, as well as several genes involved in nucleotide salvage and purine biosynthesis. The addition of ampicillin resulted in overall changes in gene expression that showed some similarity to changes induced by rifampin. The addition of the antibiotics kanamycin or norfloxacin resulted in the induction of unique gene expression signatures: a heat shock response to kanamycin and an SOS response to norfloxacin. Several genes of unknown function showed expression profiles similar to the genes associated with the SOS or the heat shock response. Thus, these profiles define families of genes with similar expression phenotypes that can be tested for related function.
Family of Shuttle Vectors for Ruminal Bacteroides
Authors: Wong Cheryl M. , Klieve Athol V. , Hamdorf Brenton J. , Schafer Darren J. , Bräu Lambert , Seet Shawn G.M. , Gregg Keith
Published: May 2003

A family of shuttle plasmids was constructed for genetic transformation of Escherichia coli and of ruminal Bacteroides strains AR20 and AR29. Plasmids were based on the replicon from Bacteroides plasmid pBI191 and were designed for studies of chromosomal integration (pBA), for the identification and study of Bacteroides gene promoters (pPPR) and for the expression of heterologous genes in Bacteroides (pBAC). Electroporation efficiency of Bacteroides was up to 105 transformants/µg plasmid, depending on the source of the DNA. The largest plasmid, pBA, was maintained at approximately 8 copies per cell in AR20 and did not measurably alter in vitro growth of transformed cells. In the current work, pBA did not integrate into the chromosomes of AR20 or AR29. The ability of plasmid pPPR to select promoter sequences was demonstrated by removal and replacement of promoters that activate the clindamycin resistance gene. The suitability of pBAC for expression of heterologous genes was demonstrated by expression of the Moraxella species fluoroacetate dehalogenase gene H1 to give intracellular activity of 7 nmol fluoride released/min/mg soluble protein in AR20 and 4 nmol/min/mg in AR29. Spontaneous loss of pBAC under non-selective conditions was 0.11–0.165% per generation, significantly less than loss of the native Bacteroides plasmid pBI191, which was lost at 0.53% per generation.
Role of Oxygen Free Radical Scavengers in Acute Renal Failure Complicating Obstructive Jaundice
Authors: Kucuk C. , Sozuer E. , Ikizceli I. , Avsarogullari L. , Keceli M. , Akgun H. , Muhtaroglu S.
Published: May 2003

Obstructive jaundice is associated with high morbidity and mortality. Major complications such as pulmonary dysfunction, renal failure and sepsis are frequently encountered. Recent studies and observations suggest that the free oxygen radicals (FORs) produced in obstructive jaundice may play a significant role in the etiopathogenesis of acute renal failure (ARF). Thirty rats were divided into three groups, as sham, control and treatment groups containing 10 rats each. Laparatomy was performed on each animal in the control and treatment groups and common bile ducts were ligated. Common bile duct was observed but was not ligated for the rats in the sham group. Saline solution injection was begun on the first day of surgical procedure and repeated once a day during the following 5 days. The same procedure was performed with oxygen radical scavenger dimethyl sulfoxide (1.5 mg/kg/day i.p.) instead of saline in the treatment group. The rats were sacrificed on the 7th postoperative day. On the 7th postoperative day, the bilirubin, urea and creatinine levels of the control and treatment groups were significantly higher in comparison with the sham group (p < 0.01). Although there was no statistically significant difference between the bilirubin levels of the control and treatment groups (p > 0.05), the urea and creatinine levels in the treatment group were significantly lower (p < 0.01). On the 7th postoperative day, the erythrocyte superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels of the control and treatment groups were significantly lower than those of the sham group (p < 0.01), whereas renal and erythrocyte malondialdehyde (MDA) levels were significantly higher (p < 0.01). Although SOD and GSH-Px levels did not differ significantly between the treatment and control groups (p > 0.05), renal and erythrocyte MDA levels of the treatment group were significantly lower than those of the control group (p < 0.01). The histopathological scores were significantly higher in the control and treatment groups (p < 0.01); there was no significant difference between the control and treatment groups (p > 0.05). FORs seem to play a significant role in the etiopathogenesis of renal failure in obstructive jaundice. Antioxidant treatment may decrease oxidative damage due to FORs and may prevent renal failure.
Hepatocyte Ploidy in Regenerating Livers after Partial Hepatectomy, Drug-Induced Necrosis, and Cirrhosis
Authors: Gandillet A. , Alexandre Eliane , Royer Cathy , Cinqualbre J. , Jaeck D. , Richert Lysiane
Published: May 2003

The hepatocyte ploidy was investigated by flow cytometry in regenerating Sprague-Dawley rat livers following either drug-induced acute necrosis (single sublethal doses of D-galactosamine or thioacetamide) or drug-induced chronic cirrhosis (repeated thioacetamide injections for 10–18 weeks) and in regenerating livers following 70% partial hepatectomy and was compared with that of normal hepatocytes. Twenty-four hours after partial hepatectomy, a significant decrease in 2n (1 diploid nucleus) hepatocytes and a significant increase in 8n (1 octoploid nucleus) hepatocytes occurred. In contrast, 24 h following induction of acute hepatic failure by single D-galactosamine or thioacetamide injections, a significant increase in 2n hepatocytes was observed, whereas the proportion of 8n hepatocytes remained unchanged. The liver ploidy returned to basal values within 21 days in all cases. In cirrhotic livers induced by chronic thioacetamide injections, the rate of 2n hepatocytes was about ten times that of the controls having the same age, while 4n (1 tetraploid nucleus) and 8n hepatocytes were one third of controls. The binucleation rate was also significantly decreased.
Mesh Implants in Hernia Repair
Authors: Rosch R. , Junge K. , Schachtrupp A. , Klinge U. , Klosterhalfen B. , Schumpelick V.
Published: May 2003

Background: In the reinforcement of the abdominal wall with mesh implants, various complications including hernia recurrence, abdominal pain, seroma formation and infection are discussed to depend on the biocompatibility of the alloplastic prosthesis. Particularly macrophages, T-cells and mast cells have been shown to play a major role in the inflammatory response to biomaterials. To approach biocompatibility of surgical meshes we therefore examined the infiltrate of these cells as well as the proliferation rate in response to different clinically applied materials. Materials and Methods: Three mesh materials (polypropylene: PP, Prolene®; polyethylene terephthalate: PET, Mersilene®, and polypropylene/polyglactin: PP + PG, Vypro®) were compared after inlay implantation in a standardized rodent animal model. A suture-closed laparotomy served as control. After 7 and 90 days of implantation, histochemical analysis of the inflammatory response to all biomaterials was performed: macrophages (ED3), T-cells (CD3), proliferating cells (PCNA) and mast cells (Giemsa) were investigated. Results:  In all groups a persisting T-cell response was observed. Colonization of the interface with macrophages showed a pronounced reduction in the PP + PG-mesh group. Infiltration of mast cells at the tissue graft interface showed a time-dependent decrease in the PET- and PP + PG-mesh groups, whereas in contrast, index of mast cells increased in the PP-mesh group. At both time points, indices of proliferation were highest in the PP-mesh group. Conclusion: The present data confirm the development of a biomaterial-dependent chronic inflammatory response to surgical meshes with macrophages as the predominant cell type. Further research on the recruitment of inflammatory cells and in particular on the role of mast cells and their granular products should be encouraged.
Thymectomy in Nonthymoma Early-Onset Myasthenia gravis in Correlation with Disease Severity and Muscle Autoantibodies
Authors: Romi F. , Gilhus N.E. , Varhaug J.E. , Myking A. , Aarli J.A.
Published: May 2003

Objective: To study the clinical effect of thymectomy in a well-defined early-onset MG subgroup and to correlate it to MG severity, the presence of circulating muscle autoantibodies, and the need for pharmacological treatment in a long-term setting. Methods: Fifty-two consecutive AChR antibody-positive early-onset MG patients (34 thymectomized and 18 nonthymectomized) were included. Severity was assessed and the pharmacological treatment monitored on a yearly basis, starting from the year of MG onset, for 5, 10, 15, and 20 consecutive years; AChR, titin, and RyR antibodies were assayed. Results: In the four follow-up groups, MG severity was significantly higher in nonthymectomized compared to thymectomized MG patients. The postthymectomy MG improvement was significant and persistent. There were 21/34 remissions in thymectomized patients and only 4/18 in the nonthymectomized group. Patients with initially high or low AChR antibody concentration had a similar thymectomy outcome. Only 6 patients had titin antibodies, and none had RyR antibodies. Conclusion: The present study indicates a benefit of thymectomy in early-onset MG. The muscle autoantibody concentration does not influence the outcome of thymectomy in early-onset MG.
Familial Idiopathic Brain Calcification – A New and Familial α-Synucleinopathy?
Authors: Lhatoo Samden D. , Perunovic Branca , Love Seth , Houlden Henry , Campbell Malcolm J.
Published: May 2003

Familial idiopathic brain calcification (FIBC) is a rare disorder characterised by autosomal dominant transmission, adult onset cerebellar and/or extrapyramidal features and idiopathic calcification of the brain. We present a family with FIBC where pathological studies showed that the proband had α-synuclein-immunopositive glial and neuronal cytoplasmic inclusions in oligodendrocytes in the putamen, midbrain and pons. This may represent a new and familial α-synuclein disorder causing a predominantly extrapyramidal picture similar to multisystem atrophy.
Lactic Dehydrogenase Isoenzyme in Cerebrospinal Fluid of Children with Infantile Spasms
Authors: Nussinovitch Moshe , Harel Daniella , Eidlitz-Markus Tali , Amir Jacob , Volovitz Benjamin
Published: May 2003

Increased levels of lactic dehydrogenase (LDH) in cerebrospinal fluid (CSF) have been reported in association with several intracranial pathologies. We studied LDH isoenzymes in the CSF of children with infantile spasms. CSF samples collected from 12 patients (aged 4–9 months) with infantile spasms were analyzed for total LDH isoenzymes activity, and were compared to samples from 15 normal children. Mean total LDH activity in the CSF was 34.62 ± 6.52 U/l. Patients with infantile spasms had a lower LDH-1 percentage and higher LDH-3 percentage; the differences from the control group were statistically significant (p < 0.01). LDH-4 and LDH-5 had similar values in both groups. Infantile spasm is apparently associated with a distinct LDH isoenzyme pattern in the CSF. More studies are needed to confirm the rise in LDH-2, LDH-3 and to determine the optimum time of analysis.
Transcranial Magnetic Stimulation Study in Hereditary Spastic Paraparesis
Authors: Nardone R. , Tezzon F.
Published: May 2003

The motor-evoked potentials and the cortical excitability by transcranial magnetic stimulation (TMS) were studied in a family with chromosome 2p linked (due to mutations in spastin) and in a family with chromosome 16q linked (due to mutations in paraplegin) hereditary spastic paraparesis (HSP), in order to evaluate the utility of these techniques in identifying the subgroups of the disease. Central motor conduction time and motor treshold to TMS were abnormal in some members of both families; the intracortical inhibition was reduced only in the affected members of the family with chromosome 2p linked HSP, even though the neurological symptoms were sometimes similar and also when clinical features reflecting cortical dysfunction were absent. The motor cortex is differentially involved in the often clinically indistinguishable forms of HSP, and TMS may help in the differential diagnosis.
Regional Cerebral Blood Flow and Episodic Memory in Parkinson’s Disease: A Single Photon Emission Tomography Study
Authors: Santens P. , de Corte T. , Vingerhoets G. , van Laere K. , Dierckx R. , De Reuck J.
Published: May 2003

In this paper we examined 46 nondemented Parkinson’s disease (PD) patients by means of perfusion single photon emission computed tomography (SPECT) and neuropsychological testing. The aim was to detect correlations of regional cerebral blood flow with episodic memory performance, using an operator-independent technique for the analysis of SPECT data. A significant positive correlation was found between prefrontal blood flow and episodic memory performances. However, age was the most important determinant of memory scores. Age also correlated significantly negatively with prefrontal perfusion. Our methodology also allowed detection of an inverse correlation of left medial temporal lobe perfusion with the memory score. This had not been found in previous studies and might indicate compensatory mechanisms in the brain of PD patients. It is concluded that episodic memory in nondemented PD patients is most dependent on the effects of aging and that the aging effects on cerebral perfusion in the PD brain parallel to a large extent the findings in normal controls.
Complement in Different Stages of HIV Infection and Pathogenesis
Authors: Speth Cornelia , Stoiber Heribert , Dierich Manfred P.
Published: May 2003

The complement system is one of the most important weapons of innate immunity and is involved in all infectious processes. It is not only a mechanism for direct protection against an invading pathogen but it also interacts with the adaptive immunity to optimize the pathogen-specific humoral and cellular defence cascade in the body. One of the greatest challenges for the complement system is infection by HIV with its chronic course and sequential destruction of immune cells and immune organs. Due to its dual role as direct effector and as fine tuner of adaptive immunity, we focussed on complement in this review and analysed in detail the contribution of complement to the antiviral defence and to HIV pathogenesis on the one hand and the complement evasion strategies of the virus on the other hand. In the present review, this interplay between complement and the virus is illuminated for the three different stages of HIV pathogenesis and for events during therapy: (1) the acute infection process with the early events in mucosa and serum; (2) the asymptomatic stage with the complex interplay between complement-induced lysis and viral evasion strategies; (3) the symptomatic infection and AIDS stage with progressive destruction of the lymph nodes, opportunistic infections and development of neuropathogenesis, and (4) finally, during highly active antiretroviral therapy and in vaccination approaches.
Comparison of Allergen-Induced Late Inflammatory Reactions in the Nose and in the Skin in House Dust Mite-Allergic Patients with or without Asthma
Authors: Lopuhaä Christa E. , de Riemer Mariëlle J. , Out Theo A. , Sjamsoedin Deman H.S. , Aalberse Rob C. , Jansen Henk M. , van der Zee Jaring S.
Published: May 2003

Background: It remains to be established which factors contribute to the occurrence of asthma in allergic individuals. We hypothesized that differences in the late allergic inflammatory reaction to allergen between asthmatic and non-asthmatic house dust mite-allergic individuals might contribute to the difference in the clinical presentation of allergy. Aim: To compare allergen-induced changes in parameters for cellular inflammation during the phase of the late allergic reaction in the skin and nose, in house dust mite-allergic individuals with or without asthma. Material and Methods: Nasal and dermal allergen challenges with house dust mite (Dermatophagoides pteronyssinus) extract were performed in 52 house dust mite-allergic individuals, of whom 26 had mild to moderate persistent asthma and 26 had perennial rhinitis without current or past asthmatic symptoms. Serial nasal lavage samples were analyzed for the presence of inflammatory cells (eosinophils and neutrophils) and soluble markers associated with cellular inflammation [interleukin-5 (IL-5), interleukin-8 (IL-8), eosinophil cationic protein (ECP) and myeloperoxidase (MPO)]. Macroscopic late phase skin reactions were studied after intracutaneous skin tests with house dust mite extract. Results: Fixed dose nasal allergen provocation elicited a similar degree of immediate allergic reaction as judged by plasma protein exudation and histamine concentrations in asthma and non-asthmatic rhinitis. Subsequently, no differences between groups were found during the phase of the late allergic reaction (4–24 h) in inflammatory cell influx, plasma protein leakage, ECP or MPO. Likewise, there were no differences in levels of chemotactic cytokines IL-5 and IL-8. In agreement with the results of nasal challenge, the late skin reaction after dermal challenge with a fixed allergen dose and after an allergen dose 10,000 times above the skin threshold for an early skin reaction did not differ between the groups. Conclusion: House dust mite-allergic patients with or without asthma have very similar late allergic inflammatory reactions in the skin and in the nose after allergen challenge. Hence, it is unlikely that the occurrence of pulmonary symptoms in asthma is explained by a general tendency of asthmatics to have an enhanced late allergic cellular inflammatory response. Nasal and dermal allergen provocations are adequate models to study allergen-induced inflammation but probably lack the pivotal link which is essential for the development of asthma.
Possible Modes of Allergen-Specific Sensitization and Boosting in an Atopic Child
Authors: Reininger R. , Exner H. , Kuderna C. , Rumpold H. , Balic N. , Valenta R. , Spitzauer S.
Published: May 2003

Several studies document that allergen-specific IgE levels are boosted by allergen contact via the respiratory tract in allergic patients. Only few data are available on whether other routes of allergen contact have an influence on systemic IgE responses. We report the case of a boy who developed egg allergy after heavy consumption of eggs by the mother during pregnancy and breast feeding. In contrast to other children who outgrow egg allergy during the first years of life, the boy experienced further dramatic increases in hen egg-specific IgE antibodies after prolonged consumption of ostrich eggs containing cross-reactive allergens. IgE antibodies to most of the important respiratory allergens remained either low or not detectable. The dramatic increases in hen egg-specific IgE antibody levels after oral intake of allergens demonstrate that systemic IgE responses in allergic patients can be strongly boosted by allergen contact via routes other than the respiratory tract.