bluuebunny/crossref_metadata_2025 huggingface dataset:
Measuring gender differences in cognitive functioning
Authors: Downing Kevin , Chan Sui‐Wah , Downing Woo‐Kyung , Kwong Theresa , Lam Tsz‐Fung
Published: April 2008

Purpose

The purpose of this paper is to investigate relationships between gender, A‐level scores and scores on the learning and study strategies inventory (LASSI) of undergraduate students.

Design/methodology/approach

The participants for this study were selected at random from the overall LASSI sampling exercise and males and females were compared using the LASSI scales at a Hong Kong University.

Findings

Gender differences in cognitive functioning and achievement do not always favour one sex with the literature related to intelligence testing suggesting that males outperform females on tests of visuo‐spatial ability, and mathematical reasoning whereas females do better on tests involving memory and language use. This paper examines relationships between gender, A‐level scores and scores (LASSI) of undergraduate students and argues that whilst there are significant gender differences in A‐level scores, these provide limited practical information at a cognitive level. In contrast, the data from LASSI allows a more detailed and practical metacognitive analysis suggesting significant gender differences in certain areas of self‐perceived performance, with females demonstrating significantly higher levels of self‐regulation and a more positive attitude to academic study than their male counterparts.

Originality/value

The analysis of the data produced by the LASSI indicates that there are significant differences in self‐perceived metacognition between the genders.
Knowledge democracy and the implications to information access
Authors: Raza Ahmad , Sohaib Murad Hasan
Published: April 2008

Purpose

The purpose of this paper is to examine the concept of “knowledge democracy,” deploying a pluralistic, and cross disciplinary and humanistic critique.

Design/methodology/approach

This is a culturally pluralistic and humanistic interpretation of globally emergent form of learning pedagogy, particularly manifested in e‐learning.

Findings

This paper explores the concept of knowledge democracy in the context of knowledge and information revolution. It has been argued that knowledge democratization implies freedom and equality to access information and knowledge across cultures and societies, particularly in the context of globalization. It is asserted that a democratization of the notion of knowledge would cause a paradigm shift; the way instruction and education are socially structured in different social systems. The knowledge society provides a new spirit of global sharing of values, acceptance of others and learning to live with divergent worldviews. It is contended that e‐learning in particular sets a new global social opportunity to transcend regional, racial and national prejudices.

Originality/value

The paper underscores the significance of pluralistic and humanistic perspective on knowledge and e‐learning.
Inter‐cultural communication: a foundation of communicative action
Authors: Vuckovic Aleksandra
Published: April 2008

Purpose

The purpose of this paper is to present a model of inter‐cultural communication that enumerates and structures latent factors affecting such communication and elaborates on the process of self‐reflection as a guiding mechanism of successful communication.

Design/methodology/approach

The five factors and various moderators that are introduced in the model are discussed by making references to existing psychology, sociology and education literature and its integration with everyday examples. Following this, overview is an argumentative discourse on self reflection and its role in inter‐cultural communication.

Findings

The paper argues that inter‐cultural communication competence can only be attained when self‐reflective processes increase a person's awareness of her own culture, personality, identity in that particular situation and various other factors. Further exposes how these factors surface in everyday situations.

Research limitations/implications

The model is at this stage purely conceptual and lacks concrete operationalisation. The factors do not necessarily present an exhaustive list.

Practical implications

By identifying relevant factors and promoting the strategic employment of self‐reflective processes, the approach can alert individuals to become more aware and thus more successful in their inter‐cultural communication. The conceptual nature of the paper can also guide future empirical research aimed at facilitating inter‐cultural communication.

Originality/value

This paper provides an introductory, meaningfully structured overview of issues that impact on inter‐cultural communication. It ties established concepts together in a novel way that can guide individual growth in the domain.
Diversification of Chinese companies: an international comparison
Authors: Fan Joseph P.H. , Huang Jun , Oberholzer‐Gee Felix , Smith Troy D. , Zhao Mengxin
Published: April 2008

Purpose

The purpose of this paper is to provide a systematic comparison of the level of business diversification in China and eight other large economies for the 2001‐2005 period. The reasons why publicly listed Chinese firms are more diversified than companies elsewhere are investigated.

Design/methodology/approach

Data were collected on the number of business segments in which publicly traded companies operate from the Thomson One Banker database and analyzed using non‐parametric tests and regression analysis.

Findings

The mean number of business segments per firm varies significantly by country. Notably, there is no evidence in the authors' sample that emerging‐market companies are systematically more diversified than their developed‐market counterparts. In most countries, firms have become less diversified over time. However, there is no such trend in China. The level of diversification of Chinese enterprises does not vary over the authors' study period (2001‐2005), making Chinese firms the most diversified in the sample by 2005. China's growth rate does not seem to explain the higher level of firm diversification. However, the authors find that Chinese state‐owned enterprises (SOEs) diversify their operations more aggressively than other Chinese firms.

Research limitations/implications

Ownership data and business group affiliations were not available for all firms in the sample, making it difficult to control for these effects across economies. The study's findings are limited to publicly traded firms.

Practical implications

Government involvement in SOEs may be contributing to a divergence in the pattern of business diversification between China and other economies.

Originality/value

This paper quantifies anecdotal evidence that Chinese firms are more diversified than similar firms in other countries.
A comparison between I‐Ching's early management decision‐making model and western management decision‐making models
Authors: Hsu Mu‐Lan , Chiu Kuan‐Yao
Published: April 2008

Purpose

The purpose of this paper is to determine the value of I‐Ching (also called Book of Changes), the ancient Chinese book of wisdom, which has been used for thousands of years to help people make decisions in daily life. Recently, eastern and western scholars have begun discussing how to apply the wisdom of I‐Ching to the field of business administration, particularly decision‐making practices.

Design/methodology/approach

A content analysis method was adopted to uncover possible modern management decision‐making constructs. The single words approach did not find frequently appearing words that integrated decision‐making constructs in the context of I‐Ching. Further uncovering I‐Ching's administrative decision‐making approach, the managerial decision‐making model of I‐Ching is explained, including the premises, the decision contingencies, and the decision process.

Findings

By using an academic comparative analysis method, as it applies to managerial decision making, I‐Ching's early management decision‐making model is subsequently compared with western management decision models, which include rational decision making, bounded‐rationality decision making, intuitive decision making, implicit favorite decision making, and garbage‐can decision making.

Research limitations/implications

The majority of scholars that study I‐Ching focus on “practice divination” research, paying attention to the interpretation or critique of the text only. Unfortunately, related literature based upon a social science research foundation is limited.

Originality/value

The value of I‐Ching was determined to lie in allowing flexibility in the decision‐making process.
Role of the HR environment on talent growth: an empirical study of industrial clusters in China
Authors: Weng Qingxiong
Published: April 2008

Purpose

In order to reveal why there are favorable growing environments in industrial clusters (IC), the author examines the effects of the HR environment on talent growth from five aspects: industrial clusters economy (ICE), industrial clusters HR policy (ICHRP), industrial clusters living setting (ICLS), industrial clusters culture (ICC) and industrial clusters HR management (ICHRM).

Design/methodology/approach

The sample for this study came from four IC in China. Exploratory factor analysis and SEM analyses were conducted to analyze data.

Findings

It proved that: the economy of ICE has a positive direct impact on the talent growth in the clusters; ICHRP has a positive direct impact on talent growth in the clusters; ICC does not have a direct impact on talent growth in the clusters; ICLS has a positive direct impact on talent growth in the clusters; the HRM of companies in IC has a positive direct impact on talent growth in the clusters; the culture and ICHRP has a positive direct impact on the HRM of companies in the clusters.

Originality/value

The paper helps to reveal why talent grows better in IC than in other regions. It offers theoretic support for government to set HR policy.
Energy policies in Latin America and the Caribbean and the evolution of sustainability
Authors: Garrón Bozo Mauricio
Published: April 2008

Purpose

The paper seeks to offer an evaluation of the energy sector's contribution to sustainable development in Latin America and the Caribbean (LAC) in the last 30 years.

Design/methodology/approach

Sustainable development indicators proposed by Latin American Energy Organization/Economic Commission for Latin America and the Caribbean/German Technical Cooperation are used, in conjunction with indicators proposed by IAEA, United Nations Department of Economic and Social Affairs, IEA, EUROSTAT and the EEA. They are based on objectives, priorities and available information and their values are analyzed in a period of significant changes in LAC energy policies.

Findings

State and evolution of sustainability in LAC are presented at a country and sub‐regional levels. Some important remarks are drawn about energy policies' contribution to sustainable development and some key areas to improve are identified.

Originality/value

This research intends to highlight implicit deficiencies in energy policies that could suggest new priority guidelines for future policy decisions, in order to improve their contribution to sustainable development.
Energy contracting in Brazil and electricity prices
Authors: Lizardo R. Hermes de Araújo João , de Aragão da Costa Agnes Maria , Correia Tiago , Melo Elbia
Published: April 2008

Purpose

To investigate the extent to which the contracting mechanisms instituted by the 2004 reform, in particular power auctions, have solved the investment hurdles created by the first reform.

Design/methodology/approach

The paper analyses the characteristics of Brazilian contracting and the experience so far with power auctions, concerning investments in generation and electricity prices.

Findings

Auctions have been moderately successful, in the sense that they have attracted a fair number of bidders and electric companies have increased their value in the stock exchange, while keeping prices moderate. However, a number of other hurdles to investment – in particular clear and feasible criteria for environmental licensing – have to be solved in order to achieve the reform goals.

Research limitations/implications

The format of power auctions is still going through a learning process; also, the experience has been limited so far, which severely hinders the use of quantitative tools. This could be the object of future research, after more data are available. Of particular interest will be the follow‐up of free bilateral contracting, which has grown significantly.

Practical implications

This could be a useful reference for scholars interested in the recent developments in the Brazilian Electricity Supply Industry.

Originality/value

As far as is known, this is the first paper to systematically analyse the performance of power auctions in the Brazilian market. Its value lies in that it allows an objective evaluation of one central point of the 2004 reform.
Benchmarking as a management and regulatory instrument for Caribbean electric utilities
Authors: Martina Steven , Hakvoort Rudi , Ajodhia Virendra
Published: April 2008

Purpose

One of the most pressing questions facing small‐island development states (SIDS) is the appropriate way in which to operate and manage their infrastructure industries. After all SIDS are faced with high cost of infrastructure due to the narrow markets and diseconomies of scale and remoteness.

Design/methodology/approach

For small‐island utilities in the Caribbean region, a benchmark has been performed to demonstrate objectively how utilities cost, as well as their service quality, compare over time and with other utilities. About 15 utilities of 17 Caribbean countries were included in the benchmark. Based on these outcomes, the current efficiency and possible efficiency gains were determined (which may differ significantly from the current “best‐practice” of utilities in developed countries) which provide a basis to set targets that are achievable.

Findings

In this paper, the conducted Caribbean benchmark studies will be further elaborated and the applicability as management tool and regulatory tool to compare performance within the region will be assessed. One of the preliminary conclusions of the study is that the incentive‐based approaches adopted in many countries do not necessarily work within the context of SIDS (and their specific characteristics and limitations), so that a different regulatory model needs to be developed.

Research limitations/implications

The analysis was performed based on data of one year. Analysis based on multi‐year data can provide trends in efficiency and will identify the development of the utilities' performance. Cost data was not used in this analysis due to lack of availability. Also, inclusion of reliability data representing frequency of interruptions and duration of interruption in the analysis would provide a more holistic indication of efficiency.

Originality/value

The paper offers insight into the current restructuring of the electricity supply in the Caribbean region.
From açaí to access: distributed electrification in rural Brazil
Authors: Zerriffi Hisham
Published: April 2008

Purpose

To rigorously examine success and failure in the use of small scale technologies for rural electrification.

Design/methodology/approach

Semi‐structured primary field interviews plus secondary sources.

Findings

Business model differences and influence of institutions important are important for understanding success and failure in rural electrification and the contribution rural electrification can play in rural development.

Research limitations/implications

Data on the entire universe of distributed electrification efforts are unavailable. This highlights the need for better documentation of energy activities in rural areas.

Practical implications

The development of new policies to guide rural electrification towards more sustainable and development enhancing outcomes.

Originality/value

Prior studies have taken anad hocapproach to study previous projects and suffer from case selection bias since their scope is limited in geography (one country, region or even village), technology (only PV or only wind or only renewables), or end‐use (household electrification and productive uses). This study proposes a clear set of independent and dependent (as well as control) variables and looks across a range of cases to draw conclusions.
Planning paths for the electrification of small villages using decentralised generation
Authors: Contreras Zaida
Published: April 2008

Purpose

The purpose of this paper is to illustrate and discuss the implications of the assessment and choice of electricity supply systems for rural communities of less than 500 inhabitants in Senegal. The paper is based on a study produced by Programme pour la Promotion de l'Electrification Rurale et l'Approvisionnement en Combustibles Domestiques, an advising body for the Senegalese Ministry of Energy and Mines.

Design/methodology/approach

The profitability index Taux d'Enrichissement en Capital is used as the main criterion for the economic evaluation of four technologies: diesel mini‐grids, photovoltaic, hybrid (pv‐diesel) generators, and solar home systems. Household demand is derived from real data of socio‐economic studies which serve as the basis for determining market segments defined by the distribution of the willingness to pay and the levels of service.

Findings

The simulations from nine demand cases show that high investment and/or operation expenditure create an insurmountable barrier given the limited payment capacity of rural populations, demonstrating that projects in this context are not profitable without subsidies. However, decentralised PV generation technologies are already demonstrated to be the least cost solution when the village lies further than 5.4 kilometers from the transmission grid.

Originality/value

This paper describes a planning path that could enable a faster implementation of rural electrification programs in remote areas considering three main elements, namely; willingness to pay, reduction of levels of supply service and support of communal management. However, the focus of the present work is mainly devoted to an analysis of the first two elements. Finally, the paper addresses the issue of how these technologies can be better implemented by national agencies and investors, with potential application outside of the Senegalese case study.
Renewable technologies for rural electrification in Colombia: a multiple objective approach
Authors: Silva Herran Diego , Nakata Toshihiko
Published: April 2008

Purpose

This study aims to present preliminary results from an integrated evaluation of electricity supply systems for rural areas using renewable energy technologies by means of a multi‐objective decision making method

Design/methodology/approach

Goal programming is applied to obtain the optimal system configuration meeting the electricity demand, based on the location's resource availability and taking diesel generation as the alternative of reference. The performance of the system is evaluated through four attributes: electricity generation costs, employment and two environmental impacts (CO2 emissions and land use). The model is designed for isolated rural area belonging to the non‐interconnected zones of Colombia.

Findings

Application of the method showed that biomass conversion technology has the highest potential and that renewable energy systems offer better performance than diesel generation. Reductions of more than 10 percent in unit electricity costs, land use rates and CO2 emissions can be achieved.

Research limitations/implications

Inclusion of additional attributes and sensitivity analysis are matters of future research.

Originality/value

The methodology used in this study is an alternative means to perform evaluation of electricity supply systems integrating several aspects of technology and which is flexible enough so as to enable the inclusion of a wider scope of interests towards energy access targets.
Corporate social orientation in Japan and the USA: a cross‐cultural comparison
Authors: Smith Wanda J. , Singal Manisha , Lamb William B.
Published: April 2008

Purpose

The primary goal of this study is to conduct an empirical comparison of corporate social orientation (CSO) values held by US and Japanese students. The study also aims to test the stability of CSO with an exploratory assessment of the impact of international exposure on these values.

Design/methodology/approach

A total of 806 respondents were surveyed in the USA and Japan regarding their expectations of business organizations, their demographic attributes, and their level of international exposure. The survey results were compared using descriptive statistics, MANOVA and ANOVA.

Findings

The results support the assertion that CSO varies across individualistic and collectivistic cultures. Statistically significant differences were found between US and Japanese respondents in the relative ratings allocated to the four dimensions of CSO (economic, legal, ethical, and discretionary expectations). Results also indicate that CSO is a fairly stable set of values. International exposure was not found to have a statistically significant impact on CSO ratings.

Research limitations/implications

This study offers support for the variability of CSO across students in different cultures. It also suggests that further studies are needed to fully assess the impact of people's experiences on their CSO. Based on the differences identified, managers in these settings can expect to have their performance evaluated differently by customers, investors, regulators, and other groups.

Originality/value

This study presents the first comparison of CSOs between the USA and Japan. The study also presents a preliminary test of the relationship between people's international exposure and CSO.
Organizational culture and compensation systems
Authors: Li Ling , Roloff Michael E.
Published: April 2008

Purpose

Compensation influences applicants' perceptions of a position's attractiveness, but there has been limited analysis of how different compensation systems might reflect organizational cultures and influence organizational attractiveness. This article seeks to explore these issues.

Design/methodology/approach

An experiment was conducted in which 288 undergraduates reacted to scenarios describing a company that distributed salaries and benefits based on either merit or on seniority. Individual differences were also measured and analyzed. Analysis of variance and moderated regression were used to test the hypotheses.

Findings

Relative to seniority‐based compensation systems, the cultures of organizations relying on merit were perceived to be more aggressive, reward‐oriented, and less decisive. Unexpectedly, the psychological contracts of organizations using merit systems were generally perceived to be more relational and less transactional than those using seniority‐based systems. Individual differences were not related to attraction to the organization regardless of its compensation systems. Finally, individuals were least attracted to organizations that distributed both salaries and benefits based on seniority relative to those using a mixed compensation distribution system or one based entirely on merit.

Research limitations/implications

The sample was composed of undergraduates who responded to a hypothetical job scenario. The scenario only included information about how salary and benefits are allocated. Future research should use more experienced samples that are considering actual positions.

Practical implications

Findings indicate how information about compensation systems might be used in job descriptions to encourage applicants.

Originality/value

This study was the first to find that merit/seniority‐based compensation systems for determining salary and benefits reflect different organizational cultures to job applicants and influence job applicants' attraction to organizations.
A folded and functional protein domain in an amyloid‐like fibril
Authors: Sackewitz Mirko , von Einem Sabrina , Hause Gerd , Wunderlich Michael , Schmid Franz‐Xaver , Schwarz Elisabeth
Published: April 2008

The effect of the polypeptide environment on polyalanine‐induced fibril formation was investigated with amyloidogenic fragments from PAPBN1, a nuclear protein controlling polyadenylation. Mutation‐caused extensions of the natural 10 alanine sequence up to maximally 17 alanines result in fibril formation of PABPN1 and the development of the disease oculopharyngeal muscular dystrophy (OPMD). We explored the influence of fibril formation on the structure and function of a one‐domain protein linked to the fibril‐forming part of PABPN1. The well‐characterized, stably folded, one‐domain protein, cold‐shock protein CspB from Bacillus subtilis, was fused either to the C terminus of the entire N‐terminal domain of PABPN1 or directly to peptides consisting of 10 or 17 alanine residues. The fusion protein between the N‐terminal domain of PABPN1 and CspB formed fibrils in which the structure and activity of CspB were retained. In the fibrils formed by fusions in which the polyalanine sequence was directly linked to CspB, CspB was unfolded. These results indicate that the folded conformation and the function of a protein domain can be maintained in amyloid‐like fibrils, and that the distance between this domain and the fibril plays an important role.
Characterization of ubiquitin and ubiquitin‐like‐protein isopeptidase activities
Authors: Nicholson Benjamin , Leach Craig A. , Goldenberg Seth J. , Francis Dana M. , Kodrasov Matthew P. , Tian Xufan , Shanks John , Sterner David E. , Bernal Alejandro , Mattern Michael R. , Wilkinson Keith D. , Butt Tauseef R.
Published: April 2008

Conjugation or deconjugation of ubiquitin (Ub) or ubiquitin‐like proteins (UBLs) to or from cellular proteins is a multifaceted and universal means of regulating cellular physiology, controlling the lifetime, localization, and activity of many critical proteins. Deconjugation of Ub or UBL from proteins is performed by a class of proteases called isopeptidases. Herein is described a readily quantifiable novel isopeptidase assay platform consisting of Ub or UBL fused to the reporter enzyme phospholipase A2 (PLA2). Isopeptidase activity releases PLA2, which cleaves its substrate, generating a signal that is linear with deubiquitylase (DUB) concentration and is able to discriminate DUB, deSUMOylase, deNEDDylase, and deISGylase activities. The power and sensitivity of the UBL‐PLA2 assay are demonstrated by its ability to differentiate the contrasting deISGylase and DUB activities of two coronavirus proteases: severe acute respiratory syndrome papain‐like protease (SARS‐CoV PLpro) and NL63 CoV papain‐like protease 2 (PLP2). Furthermore, direct comparisons with the current Ub‐7‐amino‐4‐methylcoumarin (Ub‐AMC) assay demonstrated that the Ub‐PLA2 assay is an effective tool for characterizing modulators of isopeptidase activity. This observation was expanded by profiling the inhibitory activity of the nonselective isopeptidase inhibitor NSC 632839 against DUBs and deSUMOylases. Taken together, these studies illustrate the utility of the reporter‐based approach to measuring isopeptidase activity.
Crystal structures of barley thioredoxin h isoforms HvTrxh1 and HvTrxh2 reveal features involved in protein recognition and possibly in discriminating the isoform specificity
Authors: Maeda Kenji , Hägglund Per , Finnie Christine , Svensson Birte , Henriksen Anette
Published: April 2008

H‐type thioredoxins (Trxs) constitute a particularly large Trx sub‐group in higher plants. Here, the crystal structures are determined for the two barley Trx h isoforms, HvTrxh1 and HvTrxh2, in the partially radiation‐reduced state to resolutions of 1.7 Å, and for HvTrxh2 in the oxidized state to 2.0 Å. The two Trxs have a sequence identity of 51% and highly similar fold and active‐site architecture. Interestingly, the four independent molecules in the crystals of HvTrxh1 form two relatively large and essentially identical protein–protein interfaces. In each interface, a loop segment of one HvTrxh1 molecule is positioned along a shallow hydrophobic groove at the primary nucleophile Cys40 of another HvTrxh1 molecule. The association mode can serve as a model for the target protein recognition by Trx, as it brings the Met82 Cγ atom (γ position as a disulfide sulfur) of the bound loop segment in the proximity of the Cys40 thiol. The interaction involves three characteristic backbone–backbone hydrogen bonds in an antiparallel β‐sheet‐like arrangement, similar to the arrangement observed in the structure of an engineered, covalently bound complex between Trx and a substrate protein, as reported by Maeda et al. in an earlier paper. The occurrence of an intermolecular salt bridge between Glu80 of the bound loop segment and Arg101 near the hydrophobic groove suggests that charge complementarity plays a role in the specificity of Trx. In HvTrxh2, isoleucine corresponds to this arginine, which emphasizes the potential for specificity differences between the coexisting barley Trx isoforms.
Distinguishing the cross‐β spine arrangements in amyloid fibrils using FRET analysis
Authors: Deng Wei , Cao Aoneng , Lai Luhua
Published: April 2008

The recently published microcrystal structures of amyloid fibrils from small peptides greatly enhanced our understanding of the atomic‐level structure of the amyloid fibril. However, only a few amyloid fibrils can form microcrystals. The dansyl‐tryptophan fluorescence resonance energy transfer (FRET) pair was shown to be able to detect the inter‐peptide arrangement of the Transthyretin (105–115) amyloid fibril. In this study, we combined the known microcrystal structures with the corresponding FRET efficiencies to build a model for amyloid fibril structure classification. We found that fibrils with an antiparallel structural arrangement gave the largest FRET signal, those with a parallel arrangement gave the lowest FRET signal, and those with a mixed arrangement gave a moderate FRET signal. This confirms that the amyloid fibril structure patterns can be classified based on the FRET efficiency.
Autologous bone marrow cell infusion therapy for liver cirrhosis
Authors: Sakaida Isao
Published: April 2008

The plasticity of bone marrow cells (BMC) has been confirmed by autopsy results of female recipients of BMC from male donors. To establish new clinical therapies for patients with liver cirrhosis using autologous BMC, we developed a new in vivo murine model using green fluorescent protein (GFP) and repeated carbon tetrachloride (CCl4) injection. We found that BMC infused through the tail vein, efficiently repopulated cirrhotic liver tissue and, under the influence of persistent liver damage induced by carbon tetrachloride, differentiated into albumin‐producing hepatocytes. Moreover, such BMC infusions into mice with cirrhosis improved liver function and reduced mortality. The latter observation correlated with the strong expression of matrix metalloproteinases (MMP), particularly MMP‐9, and reduced hepatic fibrosis. The results from the ‘GFP/CCl4 model’ showed that cell therapy using autologous BMC has the potential to become an effective treatment for patients with liver failure due to advanced liver cirrhosis. This review summarizes previous findings plus these recent experimental results, as well as recent clinical trials of BMC transfusion into patients with end‐stage chronic liver disease.
Polaprezinc attenuates liver fibrosis in a mouse model of non‐alcoholic steatohepatitis
Authors: Sugino Haruko , Kumagai Naoki , Watanabe Sakiko , Toda Kyoko , Takeuchi Osamu , Tsunematsu Satoshi , Morinaga Shojiroh , Tsuchimoto Kanji
Published: April 2008

Background and Aim:  The effect of polaprezinc, a zinc‐carnosine chelate compound, on the development of non‐alcoholic steatohepatitis (NASH) was investigated in dietary methionine and choline deficient (MCD) mice.

Methods:  Mice were fed the MCD diet with or without polaprezinc (2.2 g/kg diet) for 10 weeks. Liver histopathology, triglyceride and lipid peroxide levels, and the expression of genes linked to fibrosis were then assessed.

Results:  MCD mice developed steatohepatitis accompanied by mild fibrosis with an increase in lipid peroxidation, hepatic stellate cell (HSC) activation, and the augmented mRNA expression of tumor necrosis factor‐α, transforming growth factor‐β1 and procollagen α1(I). The mRNA expression levels of matrix metalloproteinase (MMP)‐2 and tissue inhibitors of metalloproteinase (TIMP)‐1 and TIMP‐2 were also enhanced. Histopathologically, polaprezinc supplementation did not influence the development of steatosis but it apparently attenuated fibrosis. Polaprezinc slightly reduced lipid peroxidation and suppressed HSC activation as well as the mRNA expression of pro‐inflammatory cytokines. Polaprezinc affected the MCD diet‐enhanced expression of TIMP‐1 even when administered relatively late.

Conclusion:  These results suggest that polaprezinc attenuates fibrosis in NASH by reducing inflammation and lipid peroxidation and, during a later phase, promoting fibrolysis via the inhibition of TIMP expression in the liver. Further investigation is required to clarify the clinical efficacy of polaprezinc in patients with NASH.
Optimal systemic hemodynamic stability for successful clinical outcomes after adult living‐donor liver transplantation: Prospective observational study
Authors: Hori Tomohide , Yagi Shintaro , Iida Taku , Taniguchi Kentaro , Yamagiwa Kentaro , Yamamoto Chiduru , Hasegawa Takashi , Yamakado Koichiro , Kato Takuma , Saito Kanako , Wang Linan , Torii Mie , Hori Yukinobu , Takeda Kan , Maruyama Kazuo , Uemoto Shinji
Published: April 2008

Background and Aim:  Most living‐donor liver transplantation (LDLT) recipients show characteristic systemic hemodynamics due to liver cirrhosis, and systemic hemodynamics after LDLT influenced postoperative graft function corresponding to outcomes. However, identities of optimal systemic hemodynamics for excellent outcomes and precise parameters for clinical strategy remain unclear.

Methods:  Therefore, we performed prospective study in adult LDLT recipients from 2003. Hemodynamic parameters were prospectively recorded, and were analyzed in 40 recipients classified into three groups: cirrhotic (group I‐C) or non‐cirrhotic recipients (group I‐NC) with good outcomes, and cirrhotic recipients (group II‐C) without good outcomes.

Results:  Group I‐C retained characteristic hyperdynamics even after LDLT. However, absolute values of parameters revealed no significant differences between groups I‐C and II‐C, because group II‐C also tended to show hyperdynamics. It is suggested that successful outcomes in cirrhotic recipients require maintenance of optimal hyperdynamic stability after LDLT, because cirrhotic vascular alterations still occurred. Because hemodynamic behaviors were different between groups I‐C and I‐NC, absolute values were also significantly different even in these successful two groups. Thus, absolute values themselves were not necessarily satisfactory for accurate evaluation of optimal hemodynamic stability. Cirrhotic hyperdynamics are symbolized in large blood volume (BV) circulated by high cardiac output (CO); therefore, we standardized CO against BV. CO/BV was significantly different between groups I‐C and II‐C, reflecting subtle variability of hyperdynamics in groups II‐C, and was interestingly constant in the two successful groups. Therefore, CO/BV reliably evaluated optimal hemodynamic stability after LDLT, and accurately predicted outcomes.

Conclusion:  Identification of inappropriate hemodynamics after LDLT is advantageous to further improve LDLT outcomes.
Des‐γ‐carboxyprothrombin, α‐fetoprotein and AFP‐L3 in patients with chronic hepatitis, cirrhosis and hepatocellular carcinoma
Authors: Durazo Francisco A , Blatt Lawrence M , Corey William G , Lin Jiing‐Huey , Han Steven , Saab Sammy , Busuttil Ronald W , Tong Myron J
Published: April 2008

Background and Aim:  Hepatocellular carcinoma (HCC) is a common complication in patients with chronic viral hepatitis. Detection of HCC at an early stage is critical for a favorable clinical outcome. The study aim was to: (i) compare the levels of des‐γ‐carboxyprothrombin (DCP), α‐fetoprotein (AFP) and AFP‐L3 in HCC patients and in chronic viral hepatitis patients without HCC; (ii) define the level of each tumor marker with the best sensitivity and specificity for HCC diagnosis; and (iii) to correlate the levels of these markers with respect to size and tumor burden.

Methods:  Two hundred and forty patients with either hepatitis B virus (HBV) or hepatitis C virus (HCV) infection were studied. These included 144 with HCC, 47 with chronic hepatitis (fibrosis stage I–III on liver biopsy) and 49 with cirrhosis.

Results:  Levels of DCP, AFP and AFP L‐3 were significantly higher in patients with HCC than in those without HCC (P ≤ 0.0001). Receiver–operating curves (ROC) indicated that the cut‐off value with the best sensitivity and specificity for each test was ≥84 mAU/mL for DCP, ≥25 ng/mL for AFP and ≥10% for AFP‐L3. The sensitivity, specificity and positive predictive value (PPV) for DCP was 87%, 85% and 86.8%, for AFP 69%, 87% and 69.8%, and for AFP‐L3 56%, 90% and 56.1%, respectively. DCP levels were below the ROC cut‐off in all patients without HCC. In patients with single lesions, there was a direct correlation of DCP to tumor size. High levels of AFP correlated with diffuse type of HCC. All three markers were significantly elevated in the presence of metastatic HCC. No advantage was observed by combining two or three markers for HCC diagnosis.

Conclusion:  DCP had the highest sensitivity and PPV for HCC diagnosis, had a direct correlation with tumor size, and was not elevated in any patients without HCC. DCP should be used as the main serum test for HCC detection.
Pegylated α‐interferon‐2a plus ribavirin compared with pegylated α‐interferon‐2b plus ribavirin for initial treatment of chronic hepatitis C virus: Prospective, non‐randomized study
Authors: Escudero Amparo , Rodríguez Felicidad , Serra Miguel A , Del Olmo Juan A , Montes Francisco , Rodrigo José M
Published: April 2008

Background and Aim:  We assessed whether the two regimens of pegylated α‐interferon‐2b (PEG‐IFN‐α2b) plus ribavirin and pegylated α‐interferon‐2a (PEG‐IFN‐α2a) plus ribavirin showed differences in terms of sustained virological response, withdrawal due to side‐effects and dose adjustment requirements in the treatment of naive chronic hepatitis C virus (HCV) patients.

Methods:  A prospective non‐randomized, open‐label comparison was made of naive HCV‐infected patients undergoing standard 24‐ or 48‐week treatment with two PEG‐IFN combined with weight‐based dosing regimen of ribavirin (PEG‐IFN‐α2a/ribavirin, n = 91; PEG‐IFN‐α2b/ribavirin, n = 92).

Results:  Sustained virological response was similar in PEG‐IFN‐α2a and PEG‐IFN‐α2b (65.9% vs 62%, P = 0.64), without differences according to genotype. In 117 patients with HCV genotype 1, the corresponding rates were 50.8% versus 46.6% (P = 0.713). Rapid virological response at 4 weeks, early virological response at 12 weeks and transient virological response were also similar. In the multivariate analysis, HCV genotype (odds ratio [OR] = 0.076, 95% confidence interval [CI] 0.029–0.198, P = 0.000) and presence of steatosis in the liver biopsy (OR = 2.799, 95% CI 1.362–5.755, P = 0.005) were significantly associated with response to antiviral therapy. The rate of withdrawals due to treatment‐related adverse events was 13.2% in the group of PEG‐IFN‐α2a and 10.9% in the group of PEG‐IFN‐α2b. Dose modification of PEG‐IFN was necessary in eight patients given PEG‐IFN‐α2a and in seven given PEG‐IFN‐α2b.

Conclusion:  The two PEG‐IFN plus ribavirin have comparable anti‐HCV activity as shown by similar percentages of patients with sustained virological response.
ATP‐binding cassette transporter A7 regulates processing of amyloid precursor protein in vitro
Authors: Chan Sharon L. , Kim Woojin Scott , Kwok John B. , Hill Andrew F. , Cappai Roberto , Rye Kerry‐Anne , Garner Brett
Published: April 2008

ATP‐binding cassette transporter A7 (ABCA7) is expressed in the brain and, like its closest homolog ABCA1, belongs to the ABCA subfamily of full‐length ABC transporters. ABCA1 promotes cellular cholesterol efflux to lipid‐free apolipoprotein acceptors and also inhibits the production of neurotoxic β‐amyloid (Aβ) peptides in vitro. The potential functions of ABCA7 in the brain are unknown. This study investigated the ability of ABCA7 to regulate cholesterol efflux to extracellular apolipoprotein acceptors and to modulate Aβ production. The transient expression of ABCA7 in human embryonic kidney cells significantly stimulated cholesterol efflux (fourfold) to apolipoprotein E (apoE) discoidal lipid complexes but not to lipid‐free apoE or apoA‐I. ABCA7 also significantly inhibited Aβ secretion from Chinese hamster ovary cells stably expressing human amyloid precursor protein (APP) or APP containing the Swedish K670M671→N670L671 mutations when compared with mock‐transfected cells. Studies with fluorogenic substrates indicated that ABCA7 had no impact on α‐, β‐, or γ‐secretase activities. Live cell imaging of Chinese hamster ovary cells expressing APP‐GFP indicated an apparent retention of APP in a perinuclear location in ABCA7 co‐transfected cells. These studies indicate that ABCA7 has the capacity to stimulate cellular cholesterol efflux to apoE discs and regulate APP processing resulting in an inhibition of Aβ production.
Zinc binding site in PICK1 is dominantly located at the CPC motif of its PDZ domain
Authors: Shi Yawei , Zhang Lei , Yuan Jingming , Xiao Hong , Yang Xiuqing , Niu Lixi
Published: April 2008

PICK1 (protein interacting with Ckinase 1) containing a PDZ domain, a BAR domain, and two short acidic regions is as an adaptor protein that plays an important role in α‐amino‐3‐hydroxy‐5‐methylisoxazole‐4‐propionic acid receptor trafficking, cell morphology and migration, as well as in some diseases such as cancer, schizophrenia and pain. To better understand the physiological function of PICK1, we expressed the recombinant PICK1 and its truncated mutants in E.coli, and measured their zinc binding properties by fluorescence and competition assay. It is shown that PICK1 has one Zn2+‐binding site. The Zn2+‐binding properties of PICK1 are not appreciably affected after the removal of BARC domain (involving BAR domain and C‐terminal acidic region). Deleting the N‐terminal acidic region of NPDZ domain (involving PDZ domain and N‐terminal acidic region) in PICK1 impairs its Zn2+‐binding capacity.The mutation of the CPC (Cys‐Pro‐Cys) motif in the PDZ domain of PICK1 abolishes the ability of Zn2+‐binding. In addition, Zn2+ can enhance the lipid‐binding ability of PDZ domain as observed in both protein‐lipid overlay assay and fluorescence analysis. The results presented in this report suggested that Zn2+ plays a regulatory role in the trafficking of PICK1 from the cytoplasm to cell membrane.
Inhibitory effects of aripiprazole on interferon‐γ‐induced microglial activation via intracellular Ca2+ regulation in vitro
Authors: Kato Takahiro , Mizoguchi Yoshito , Monji Akira , Horikawa Hideki , Suzuki Satoshi O. , Seki Yoshihiro , Iwaki Toru , Hashioka Sadayuki , Kanba Shigenobu
Published: April 2008

The activation of the inflammatory/immunological response system is suggested to be related to the pathophysiology of schizophrenia. Aripiprazole is a novel atypical antipsychotic, which is a high‐affinity dopamine D2 receptor partial agonist. Atypical antipsychotics, all of which have dopamine D2 receptor antagonism, have recently reported to have significantly inhibitory effects on interferon (IFN)‐γ‐induced microglial activation in vitro. In the present study, we investigated whether or not aripiprazole also has anti‐inflammatory effect on IFN‐γ‐induced microglial activation. Not quinpirole, dopamine D2 full agonist, but aripiprazole significantly inhibited the generation of nitric oxide (NO) and tumor necrosis factor (TNF)‐α from IFN‐γ‐activated microglia and suppressed the IFN‐γ‐induced elevation of intracellular Ca2+ concentrations ([Ca2+]i) in murine microglial cells. Increased [Ca2+]i has been reported to be required, but by itself not sufficient, for the release of NO and certain cytokines. As a result, we can speculate that aripiprazole may inhibit IFN‐γ‐induced microglial activation through the suppression of IFN‐γ‐induced elevation of [Ca2+]i in microglia. Our results demonstrated that not only antipsychotics which have dopamine D2 receptor antagonism but also aripiprazole have anti‐inflammatory effects via the inhibition of microglial activation. Antipsychotics may therefore have a potentially useful therapeutic effect on patients with schizophrenia by reducing the microglial inflammatory reactions.
Expression of mRNA for specific fibroblast growth factors associates with that of the myogenic markers MyoD and proliferating cell nuclear antigen in regenerating and overloaded rat plantaris muscle
Authors: Tanaka Y. , Yamaguchi A. , Fujikawa T. , Sakuma K. , Morita I. , Ishii K.
Published: April 2008

Aim:  To examine the relations between specific fibroblast growth factors (FGFs) and satellite cell activation during muscle regeneration and hypertrophy in vivo, we measured mRNA expression of FGFs and myogenic markers in rat plantaris muscle after bupivacaine administration and synergist ablation.

Methods:  mRNA levels for MyoD, myogenin, proliferating cell nuclear antigen (PCNA), p21, M‐cadherin, Pax7, FGF‐1, FGF‐2, FGF‐3, FGF‐4, FGF‐5, FGF‐6, FGF‐7, FGF‐8 and hepatocyte growth factor (HGF) were measured continually for up to 72 h after bupivacaine administration and synergist ablation. FGF‐5, FGF‐7 and HGF proteins were immunostained at 72 h after bupivacaine administration.

Results:  MyoD and PCNA mRNAs started increasing 24 h after bupivacaine administration. Myogenin, p21, M‐cadherin and Pax7 mRNAs started to increase after 48 and 72 h. After synergist ablation, MyoD, PCNA, M‐cadherin and Pax7 mRNAs had increased at 24 and 48 h, and myogenin and p21 mRNAs at 12 and 24 h. FGF‐1, FGF‐7 and HGF mRNAs after the treatments started to increase at the same time as MyoD and PCNA mRNAs. FGF‐5 was expressed at the same time as MyoD and PCNA mRNAs after bupivacaine administration but did not after the ablation. FGF‐2, FGF‐3, FGF‐4, FGF‐6 and FGF‐8 mRNAs were not associated with the expression of the myogenic markers. FGF‐7 and HGF proteins were expressed in immature muscle fibre nuclei and the extracellular matrix, but FGF‐5 protein was preferentially expressed in extracellular matrix.

Conclusion:  These results indicate that FGF‐1, FGF‐7 and HGF are associated with specific myogenic marker expression during muscle regeneration and hypertrophy.