bluuebunny/crossref_metadata_2025 huggingface dataset:
Two proteins with 6‐cys motifs are required for malarial parasites to commit to infection of the hepatocyte
Authors: Ishino Tomoko , Chinzei Yasuo , Yuda Masao
Published: September 2005

Many intracellular pathogens have host cells suitable for their proliferation, and selectively invade them using specific host–parasite interactions. Malarial sporozoites, the liver‐invasive forms, are effectively targeted to hepatocytes and proliferate in them. So far, however, sporozoite molecules that mediate the specific infection of hepatocytes remain unknown. Here we report that two proteins, Pbs36p and Pbs36, belonging to the plasmodium 6‐cys domain protein family, carry out this function. We found that these molecules are specifically produced in liver‐infective sporozoites. Target disruption of the respective genes nearly abolished sporozoite infectivity in the mammalian host. Invasion assays revealed that the mutant parasites could not commit to infection, even when they encounter with hepatocytes, resulting in continuous traversal of hepatocytes. These results suggest that these proteins are necessary for sporozoites to recognize hepatocytes and commit to infection. This finding might lead to novel anti‐malarial strategies that prevent sporozoite infection of the hepatocyte.
DNA polymerase II as a fidelity factor in chromosomal DNA synthesis in Escherichia coli
Authors: Banach‐Orlowska Magdalena , Fijalkowska Iwona J. , Schaaper Roel M. , Jonczyk Piotr
Published: September 2005

Escherichia coli DNA polymerase III holoenzyme (HE) is the main replicase responsible for replication of the bacterial chromosome. E. coli contains four additional polymerases, and it is a relevant question whether these might also contribute to chromosomal replication and its fidelity. Here, we have investigated the role of DNA polymerase II (Pol II) (polB gene product). Mismatch repair‐defective strains containing the polBex1 allele – encoding a polymerase‐proficient but exonucleolytically defective Pol II – displayed a mutator activity for four different chromosomal lac mutational markers. The mutator effect was dependent on the chromosomal orientation of the lacZ gene. The results indicate that Pol II plays a role in chromosomal replication and that its role is not equal in leading‐ versus lagging‐strand replication. In particular, the role of Pol II appeared larger in the lagging strand. When combined with dnaQ or dnaE mutator alleles, polBex1 showed strong, near multiplicative effects. The results fit a model in which Pol II acts as proofreader for HE‐produced misinsertion errors. A second role of Pol II is to protect mismatched 3′ termini against the mutagenic action of polymerase IV (dinB product). Overall, Pol II may be considered a main player in the polymerase trafficking at the replication fork.
A role for topoisomerase III in a recombination pathway alternative to RuvABC
Authors: Lopez Christopher R. , Yang Shirley , Deibler Richard W. , Ray Starlight A. , Pennington Jeanine M. , DiGate Russell J. , Hastings P. J. , Rosenberg Susan M. , Zechiedrich E. Lynn
Published: September 2005

The physiological role of topoisomerase III is unclear for any organism. We show here that the removal of topoisomerase III in temperature sensitive topoisomerase IV mutants in Escherichia coli results in inviability at the permissive temperature. The removal of topoisomerase III has no effect on the accumulation of catenated intermediates of DNA replication, even when topoisomerase IV activity is removed. Either recQ or recA null mutations, but not helD null or lexA3, partially rescued the synthetic lethality of the double topoisomerase III/IV mutant, indicating a role for topoisomerase III in recombination. We find a bias against deleting the gene encoding topoisomerase III in ruvC53 or ΔruvABC backgrounds compared with the isogenic wild‐type strains. The topoisomerase III RuvC double mutants that can be constructed are five‐ to 10‐fold more sensitive to UV irradiation and mitomycin C treatment and are twofold less efficient in transduction efficiency than ruvC53 mutants. The overexpression of ruvABC allows the construction of the topoisomerase III/IV double mutant. These data are consistent with a role for topoisomerase III in disentangling recombination intermediates as an alternative to RuvABC to maintain the stability of the genome.
Transcriptional activation of the pathway‐specific regulator of the actinorhodin biosynthetic genes in Streptomyces coelicolor
Authors: Uguru Gabriel C. , Stephens Karen E. , Stead Jonathan A. , Towle Jane E. , Baumberg Simon , McDowall Kenneth J.
Published: September 2005

The Streptomyces produce a plethora of secondary metabolites including antibiotics and undergo a complex developmental cycle. As a means of establishing the pathways that regulate secondary metabolite production by this important bacterial genus, the model species Streptomyces coelicolor and its relatives have been the subject of several genetic screens. However, despite the identification and characterization of numerous genes that affect antibiotic production, there is still no overall understanding of the network that integrates the various environmental and growth signals to bring about changes in the expression of biosynthetic genes. To establish new links, we are taking a biochemical approach to identify transcription factors that regulate antibiotic production in S. coelicolor. Here we describe the identification and characterization of a transcription factor, designated AtrA, that regulates transcription of actII‐ORF4, the pathway‐specific activator of the actinorhodin biosynthetic gene cluster in S. coelicolor. Disruption of the corresponding atrA gene, which is not associated with any antibiotic gene cluster, reduced the production of actinorhodin, but had no detectable effect on the production of undecylprodigiosin or the calcium‐dependent antibiotic. These results indicate that atrA has specificity with regard to the biosynthetic genes it influences. An orthologue of atrA is present in the genome of Streptomyces avermitilis, the only other streptomycete for which there is a publicly available complete sequence. We also show that S. coelicolor AtrA can bind in vitro to the promoter of strR, a transcriptional activator unrelated to actII‐ORF4 that is the final regulator of streptomycin production in Streptomyces griseus. These findings provide further evidence that the path leading to the expression of pathway‐specific activators of antibiotic biosynthesis genes in disparate Streptomyces may share evolutionarily conserved components in at least some cases, even though the final activators are not related, and suggests that the regulation of streptomycin production, which serves an important paradigm, may be more complex than represented by current models.
Clustered genes required for synthesis and deposition of envelope glycolipids in Anabaena sp. strain PCC 7120
Authors: Fan Qing , Huang Guocun , Lechno‐Yossef Sigal , Wolk C. Peter , Kaneko Takakazu , Tabata Satoshi
Published: September 2005

Photoreduction of dinitrogen by heterocyst‐forming cyanobacteria is of great importance ecologically and for subsistence rice agriculture. Their heterocysts must have a glycolipid envelope layer that limits the entry of oxygen if nitrogenase is to remain active to fix dinitrogen in an oxygen‐containing milieu (the Fox+ phenotype). Genes alr5354 (hglD), alr5355 (hglC) and alr5357 (hglB) of the filamentous cyanobacterium, Anabaena sp. strain PCC 7120, and hglE of Nostoc punctiforme are required for synthesis of heterocyst envelope glycolipids. Newly identified Fox– mutants bear transposons in nearby open reading frames (orfs) all5343, all5345–asr5349 and alr5351–alr5358. Complementation and other analysis provide evidence that at least orfs all5343 (or a co‐transcribed gene), all5345, all5347, alr5348, asr5350–alr5353 and alr5356, but not asr5349, are also required for a Fox+ phenotype. Lipid and sequence analyses suggest that alr5351–alr5357 encode the enzymes that biosynthesize the glycolipid aglycones. Electron microscopy indicates a role of all5345 through all5347 in the normal deposition of the envelope glycolipids.
Binding of the Streptococcus gordonii surface glycoproteins GspB and Hsa to specific carbohydrate structures on platelet membrane glycoprotein Ibα
Authors: Takamatsu Daisuke , Bensing Barbara A. , Cheng Hui , Jarvis Gary A. , Siboo Ian R. , López José A. , Griffiss J. McLeod , Sullam Paul M.
Published: September 2005

GspB and Hsa are homologous serine‐rich surface glycoproteins of Streptococcus gordonii strains M99 and Challis, respectively, that mediate the binding of these organisms to platelet membrane glycoprotein (GP) Ibα. Both GspB and Hsa consist of an N‐terminal putative signal peptide, a short serine‐rich region, a region (BR) that is rich in basic amino acids, a longer serine‐rich region and a C‐terminal cell wall anchoring domain. To further assess the mechanisms for GspB and Hsa binding, we investigated the binding of the BRs of GspB and Hsa (expressed as glutathione S‐tranferase fusion proteins) to sialylated glycoproteins in vitro. Both fusion proteins showed significant levels of binding to sialylated moieties on fetuin and GPIbα. In contrast, the corresponding region of a GspB homologue of Streptococcus agalactiae, which is acidic rather than basic, showed no binding to either fetuin or GPIbα. As measured by surface plasmon resonance kinetic analysis, GspB‐ and Hsa‐derived fusion proteins had high affinity for GPIbα, but with somewhat different dissociation constants. Dot blot analysis using a panel of synthesized oligosaccharides revealed that the BR of Hsa can bind both α(2‐3) sialyllactosamine [NeuAcα(2‐3)Galβ(1‐4)GlcNAc] and sialyl‐T antigen [NeuAcα(2‐3)Galβ(1‐3)GalNAc], whereas the BR of GspB only bound sialyl‐T antigen. Moreover, far Western blotting using platelet membrane proteins revealed that GPIbα is the principal receptor for GspB and Hsa on human platelets. The combined results indicate that the BRs of GspB and Hsa are the binding domains of these adhesins. However, the subsets of carbohydrate structures on GPIbα recognized by the binding domains appear to be different between the two proteins.
Trypanosomes change their transferrin receptor expression to allow effective uptake of host transferrin
Authors: Van Luenen Henri G. A. M. , Kieft Rudo , Mußmann Rainer , Engstler Markus , Ter Riet Bas , Borst Piet
Published: September 2005

In its mammalian host, Trypanosoma brucei covers its iron requirements by receptor‐mediated uptake of host transferrin (Tf). The Tf‐receptor (Tf‐R) is a heterodimeric membrane protein encoded by expression site‐associated gene (ESAG) 6 and 7 located promoter‐proximal in a polycistronic expression site (ES). Each of the 20 ESs encodes a slightly different Tf‐R; these differences strongly affect the binding affinity for Tfs of different hosts. The Tf‐R encoded in the 221 ES has a low affinity for dog Tf. Transfer of trypanosomes with an active 221 ES to dilute dog serum leads to growth arrest, which they can overcome by switching to another ES encoding a Tf‐R with higher affinity for dog Tf. Here we show that trypanosomes can also adapt to dilute dog serum without switching but by replacing the ESAG7 gene in the 221 ES by one from another ES, by deleting ESAG7 from the 221 ES with concomitant upregulation of transcription of ESAG7 in ‘silent’ ESs, by grossly overproducing the 221 Tf‐R or by combinations of these alterations. Our results illustrate the striking genetic flexibility of trypanosomes.
Genetic regulation mediated by thiamin pyrophosphate‐binding motif in Saccharomyces cerevisiae
Authors: Nosaka Kazuto , Onozuka Mari , Konno Hiroyuki , Kawasaki Yuko , Nishimura Hiroshi , Sano Mamoru , Akaji Kenichi
Published: September 2005

The expression of genes of Saccharomyces cerevisiae encoding the enzymes involved in the metabolism of thiamin (THI genes) is co‐ordinately repressed by exogenous thiamin and induced in the absence of thiamin. In this yeast THI regulatory system acts mainly at the transcriptional level, thiamin pyrophosphate (TDP) seems to serve as a corepressor, and genetic studies have identified three positive regulatory factors (Thi2p, Thi3p and Pdc2p). We found in a DNA microarray analysis that the expression of THI genes increased 10‐ to 90‐fold in response to thiamin deprivation, and likewise, the expression of THI2 and THI3 increased 17‐fold and threefold, respectively. After transfer from repressing to inducing medium, the promoter activity of both THI2 and THI3 increased in parallel with that of PHO3, one of THI genes. The stimulation of THI3 promoter activity was diminished by deletion of THI3, indicative of the autoregulation of THI3. The THI genes were not induced when THI2 was expressed from the yeast GAL1 promoter in a thi3Δ strain or when THI3 was expressed in a thi2Δ strain, suggesting that Thi2p and Thi3p participate simultaneously in the induction. When mutant Thi3p proteins lacking TDP‐binding activity were produced in the thi3Δ strain, THI genes were expressed even under thiamin‐replete conditions. This result supports the hypothesis that Thi3p senses the intracellular signal of the THI regulatory system to exert transcriptional control. Furthermore, Thi2p and Thi3p were demonstrated to bind each other and this interaction was partially diminished by exogenous thiamin, suggesting that Thi2p and Thi3p stimulate the expression as a complex whose function is disturbed by TDP bound to Thi3p. We discuss the possibility that the induction of THI genes is triggered by the activation of the complex attributed to decrease in intracellular TDP and the elevated complex in the autoregulatory fashion further upregulates THI genes. This is the first report of the involvement of the TDP‐binding motif in genetic regulation.
Cell wall integrity is dependent on the PKC1 signal transduction pathway in Cryptococcus neoformans
Authors: Gerik Kimberly J. , Donlin Maureen J. , Soto Carlos E. , Banks Annette M. , Banks Isaac R. , Maligie Marybeth A. , Selitrennikoff Claude P. , Lodge Jennifer K.
Published: September 2005

Cell wall biogenesis and integrity are crucial for fungal growth, pathogenesis and survival, and are attractive targets for antifungal therapy. In this study, we identify, delete and analyse mutant strains for 10 genes involved in the PKC1 signal transduction pathway and its regulation in Cryptococcus neoformans. The kinases Bck1 and Mkk2 are critical for maintaining integrity, and deletion of each of these causes severe phenotypes different from each other. In stark contrast to results seen in Saccharomyces cerevisiae, a deletion in LRG1 has severe repercussions for the cell, and one in ROM2 has little effect. Also surprisingly, the phosphatase Ppg1 is crucial for cell integrity. These data indicate that the mechanisms of maintaining cell integrity differ between the two fungi. Deletions in SSD1 and PUF4, potential alternative regulators of cell integrity, also exhibit phenotypes. This is the first comprehensive analysis examining genes involved the maintenance of cell integrity in C. neoformans and sets the foundation for future biochemical and virulence studies.
VqsM, a novel AraC‐type global regulator of quorum‐sensing signalling and virulence in Pseudomonas aeruginosa
Authors: Dong Yi‐Hu , Zhang Xi‐Fen , Xu Jin‐Ling , Tan Ai‐Tee , Zhang Lian‐Hui
Published: September 2005

Human pathogen Pseudomonas aeruginosa uses quorum‐sensing (QS) signalling systems to synchronize the production of virulence factors. There are two interrelated QS systems, las and rhl, in P. aeruginosa. In addition to this complexity, a number of transcriptional regulators were shown to have complicated interplays with las and rhl central QS components. Here, we describe a novel virulence and QS modulator (VqsM) that positively regulates the QS systems in P. aeruginosa. Mutation in vqsM resulted in much reduced production of N‐acylhomoserine lactones (AHLs) and extracellular enzymes. Sequence analysis revealed that vqsM encodes a transcriptional regulator with an AraC‐type helix–turn–helix DNA binding domain at the C‐terminal of the peptide. Global gene expression profile analysis showed at least a total of 302 genes to be influenced, directly or indirectly, by VqsM. Among the 203 VqsM‐promoted genes, 52.2% were known to be QS upregulated. Several genes encoding the key regulators implicated in QS, such as rhlR, rsaL, vqsR, mvfR, pprB and rpoS, and two AHL synthesis genes, lasI and rhlI, were suppressed in the vqsM mutant. Similar to the ‘AHL‐blind’ phenotype of vqsR and pprB mutants, vqsM mutant did not respond to external addition of N‐3‐oxo‐dodecanoyl‐homoserine lactone signals. Moreover, overexpression of vqsR in vqsM mutant more or less restored the production of both AHL and virulence factors. The results demonstrate that VqsM, largely through modulation of vqsR expression, plays a vital role in regulation of QS signalling in P. aeruginosa.
Tobacco bZIP transcription factor TGA2.2 and related factor TGA2.1 have distinct roles in plant defense responses and plant development
Authors: Thurow Corinna , Schiermeyer Andreas , Krawczyk Stefanie , Butterbrodt Thomas , Nickolov Kaloian , Gatz Christiane
Published: September 2005

Salicylic acid (SA) is a crucial internal signaling molecule needed for the induction of plant defense responses upon attack of a variety of pathogens. Basic leucine zipper transcription factors of the TGA family bind to activating sequence‐1 (as‐1)‐like elements which are SA‐responsive cis elements found in promoters of ‘immediate early’ and ‘late’ SA‐inducible genes. TGA2.2 constitutes the main component of tobacco as‐1‐binding factor‐1 (ASF‐1). TGA2.1, which differs from TGA2.2 by being able to activate transcription in yeast, constitutes a minor fraction of the complex. Both proteins interact with NPR1, a protein essential for SA inducibility of ‘late’ genes. Here we demonstrate using dsRNAi mediated gene silencing that reducing the amount of TGA2.2 and TGA2.1 correlates with a significant decrease in ASF‐1 activity and with a decreased inducibility of both ‘immediate early’ and ‘late’ genes. In contrast, reducing the amount of TGA2.1 alone had no effect on the expression of these target genes suggesting that TGA2.1 is dispensable for SA‐inducible gene expression from the as‐1 element. Expression of a TGA2.2 mutant unable to form heterodimers with the endogenous pool of TGA factors led to reduced SA‐inducibility of ‘immediate early’ gene Nt103, indicating that the native leucine zipper is important for the protein to act positively on transcription. Plants with reduced amounts of TGA2.1 developed petal like stamens indicating a regulatory role of TGA2.1 in defining organ identity in tobacco flowers. A model is suggested that unifies conflicting results on the function of tobacco TGA factors with respect to activation of the ‘late’PR‐1a promoter.
Antisense oligodeoxynucleotide inhibition as a potent strategy in plant biology: identification of SUSIBA2 as a transcriptional activator in plant sugar signalling
Authors: Sun Chuanxin , Höglund Anna‐Stina , Olsson Helena , Mangelsen Elke , Jansson Christer
Published: September 2005

Sugar signalling cascades are important components of regulatory networks in cells. Compared with the situation in bacteria, yeast and animals, participants of the sugar signalling pathways in plants are poorly understood. Several genes involved in starch synthesis are known to be sugar inducible, although the signal transduction pathways remain undisclosed. We reported recently the isolation of SUSIBA2, a transcription factor involved in sugar‐mediated regulation of starch synthesis. Here, we used antisense oligodeoxynucleotide (ODN) inhibition, a powerful approach in medical sciences, to block the effects of SUSIBA2 in sugar‐treated barley leaves. The uptake and intracellular trafficking of an 18‐mer susiba2 antisense ODN in leaves were followed by confocal microscopy. Administration of the antisense ODN to the leaves impeded susiba2 expression by RNase H activation. This dramatically diminished the ectopic expression of the iso1 and sbeIIb genes and resulted in altered starch synthesis. This study illustrates the successful exploitation of the antisense ODN technology in plant biology, e.g. as a rapid antecedent to time‐consuming transgenic studies, and identifies SUSIBA2 as a transcriptional activator in plant sugar signalling. Based on our findings, we propose a model for sugar‐signalling control of starch synthesis.
US Credit Unions: An Empirical Investigation of Size, Age and Growth
Authors: Goddard John , Wilson John O. S.
Published: September 2005

Abstract**:  An econometric analysis of the growth performance of US credit unions for the period 1992–2001 investigates empirical relationships between size, age and growth. Ceteris paribus larger credit unions grew faster than smaller unions. State credit unions grew faster than federal credit unions, and single bond credit unions grew faster than multiple bond credit unions. The size‐growth gradients were generally steeper for state than for federal credit unions, and for single bond than for multiple bond credit unions. These patterns are attributed to variations in legislation and regulatory treatment. There is some evidence that younger credit unions tended to outgrow older ones. This seems consistent with a life cycle typology of credit union growth and development. There is also evidence of a positive persistence of growth effect. The cross‐sectional variance of growth is inversely related to size, but is largely independent of age.
Imposing Capital Controls on Credit Unions: An Analysis of Regulatory Intervention in Australia
Authors: Greinke Andrew
Published: September 2005

Abstract**:  What impacts would minimum capital requirements have on mutual institutions lacking the ability to raise equity capital? Can the response of credit unions to capital controls be explained by internal member bonding? The imposition of capital controls on credit unions by the Australian Financial Institutions Commission is studied as a Box‐Tiao time series quasi‐experiment. Time series intervention and trend analyses are performed on a sample of 150 credit unions over the period 1987 to 1997, together with cross‐sectional regressions of the estimated responses. The results demonstrate that the capital controls had a significant impact on credit union behavior. Consistent with theoretical expectations, the response of individual credit unions is found to be a function of initial capital levels and internal member bonding.
An Investigation into the Link between UK Credit Union Characteristics, Location and their Success
Authors: Ward Ann‐Marie , McKillop Donal G.
Published: September 2005

Abstract**:  The unique characteristics of credit unions reduces the information asymmetry that is prevalent in credit making decisions, enabling them to provide loans where other financial institutions cannot. This makes them a potential tool in the fight against financial exclusion. Yet, the UK credit union movement is not regarded as being successful, even though there is evidence of much financial exclusion. This study is cross sectional in form, and evaluates characteristics that may contribute to the success of the UK credit union movement at national and regional level, in 2000. The findings are used to consider the impact of recent regulatory changes on the movement. The key findings are that there is a significant relationship between the success of a credit union, its size and the deprivation of the ward from which it sources its members. More specifically, larger credit unions and those located in more affluent wards, are more successful. Affiliation to the Irish League of Credit Unions and having a common bond of occupation, are also found to be contributing factors to credit union success. These results are taken as providing support for the recent changes implemented by the Financial Services Authority (FSA), which is likely to result in the emergence of larger credit unions (through mergers), run by appropriately qualified persons, serving a more mixed‐income membership base. It is, however, noted that the history of the UK movement is one of missed opportunities and only time will tell whether credit unions have the wherewithal to accept current opportunities.
Morphometric Characteristics of the Ophthalmic Rete in the Goose Living at High Altitudes and Cold Climate Conditions
Authors: Aslan K. , Kürtül İ. , ÖZcan S. , Aksoy G.
Published: September 2005

This study has aimed at observing in detail the degree of complexity in the formation of the ophthalmic rete in geese living at high altitudes and very cold climate conditions in Kars and its province of Turkey. The 15 adult geese were injected with red and blue coloured latex, dissection was performed, the rete was examined, and the vessels were counted macroscopically and by stereoscopic microscopy. The size and the afferent and efferent vessels of the rete were mostly in parallel with the literature. The numbers of the vessels in the rete of the male and female geese were between 8.3 ± 1.1 and 9.3 ± 1.1 in arteries, and 8.6 ± 1.4 and 10.5 ± 1.3 in veins respectively. The results suggest that the ophthalmic rete in the goose living at high altitudes and very cold conditions may tend to be less complex, which might be the result of the relatively less cooling needs of the brain at cold conditions.
Expression and Localization of Growth Factors and their Receptors in the Mammalian Testis. Part I: Fibroblast Growth Factors and Insulin‐Like Growth Factors
Authors: Abo‐Elmaksoud A. , Sinowatz F.
Published: September 2005

It is now well established that normal development and function of testis are mediated by endocrine and paracrine pathways including hormones, growth factors and cytokines as well as by direct cell‐to‐cell contacts depending on tight, adhering and gap junctions. In the last two decades, several growth factors were identified in the testis of various mammalian species. Growth factors are shown to promote cell proliferation, regulate tissue differentiation, and modulate organogenesis. Interestingly, most of these peptides are expressed not only in the adult mammalian testis during spermatogenesis but also during testicular morphogenesis in prenatal and postnatal life. Our study was launched to provide an overview of the expression, localization, and putative physiological roles of growth factors and their receptors in the mammalian testis. The growth factors considered in this part of our review are fibroblast growth factors and insulin‐like growth factors. These factors are found in testicular cells in prenatal, postnatal, and adult animals and are implicated in the regulation of important testicular activities including testicular cord morphogenesis, modulation of testicular hormone secretion and control of spermatogenesis.
Online technology in rural health: Supporting students to overcome the tyranny of distance
Authors: McLeod Sharynne , Barbara Anita
Published: September 2005

Objective:  To determine allied health students’ perceptions of the usefulness of online chat as a support mechanism while on fieldwork.

Design:  Questionnaire.

Setting:  Fieldwork predominantly in rural allied health settings.

Subjects:  Ninety‐seven students studying occupational therapy and speech pathology.

Results:  Students indicated that the major advantage of using online chat while on fieldwork placement was getting peer support (59%), gaining advice (22%) and having contact with the lecturer (15%). The majority of students indicated that they would like to have an online chat room for their next fieldwork placement (72%) and to use online chat when they were practising clinicians (57%). Although 95% of the students attempted to access online chat during their fieldwork placement, only 67% were actually able to participate. Students had difficulty accessing online chat through hospital and community health settings, so instead had to access it via local schools, homes, universities and libraries to use the technology.

Conclusion:  The use of online chat rooms was seen to be beneficial to encouraging peer support while on fieldwork for allied health students.
Nutrition status of primary school children in Townsville
Authors: Heath Deanne L. , Panaretto Kathryn S.
Published: September 2005

Objective:  Much of the ill health of Australian Indigenous populations can be attributed to diet‐related diseases. Many of these diseases and the deleterious dietary choices are thought to begin in early childhood. This project therefore aimed to assess the nutritional health status of children in Townsville. It enabled the Townsville Aboriginal and Islander community to identify and redress nutrition‐related issues considered important in improving the overall health status of their community.

Design:  Baseline urinalysis, anthropometrics, general overall health assessment, dietary and exercise histories were collected. This screening was repeated annually. Diet and exercise histories were recorded biannually.

Setting:  Based in three Northern Queensland health region (pre)primary schools with a high proportion of Indigenous children.

Results:  Baseline results demonstrated that more children are overweight to obese than underweight. There was no significant difference in body mass index between Indigenous and Non‐Indigenous children. Indigenous children were shown to consume less vegetable and dairy products and were significantly more likely to suffer from anaemia, iron depletion and eosinophilia than non‐Indigenous children. Indigenous children were also twice as likely to have runny noses and are more than three times more likely to have skin sores.

Conclusion:  These results support that the health status of the Indigenous children is poorer than that of non‐Indigenous children. They demonstrate an immediate need to implement culturally appropriate nutritional and exercise programs within the school environment to improve dietary habits and overall health. Implementation of nutritional, drinking and exercise programs may significantly improve these children's overall awareness and behaviour concerning nutrition and health.
Exploration of the link between conceptual occupational therapy models and the International Classification of Functioning, Disability and Health
Authors: Stamm Tanja A. , Cieza Alarcos , Machold Klaus , Smolen Josef S. , Stucki Gerold
Published: September 2005

Background and Aim:  Because occupational therapy focuses on occupations and activities of daily living in the context of the environment, conceptual occupational therapy models might be closely related to the International Classification of Functioning, Disability and Health (ICF). The purpose of this paper is to explore the link of conceptual occupational therapy models to the ICF.

Methods and Results:  A structured literature search was performed. The concepts on which the models are built were linked to the ICF categories and components according to 10 established linking rules. Three conceptual occupational therapy models were identified in the literature: the Model of Human Occupation, the Canadian Model of Occupational Performance and the Occupational Performance Model (Australia). The majority of the concepts from the three models could be linked to the ICF.

Conclusion:  By applying the conceptual models, occupational therapists might add an additional perspective to multidisciplinary teams that use the ICF.
Dynamic Occupational Therapy Cognitive Assessment for Children: Perceived utility in Australian occupational therapy practice
Authors: Rodger Sylvia , Daley Emma , Hughes Kate , Ziviani Jenny
Published: September 2005

Background and Aim: The Dynamic Occupational Therapy Cognitive Assessment for Children (DOTCA‐Ch), recently developed in Israel, assesses the cognitive areas: orientation, spatial perception, praxis, visuomotor construction and thinking operations of 6‐ to 12‐year‐old children. The dynamic aspect, which incorporates mediation and prompting, has been presented as a valuable clinical feature of this new assessment. This study investigated the cultural suitability, dynamic nature and comprehensiveness of the DOTCA‐Ch as a single cognitive assessment for occupational therapy practice in Australia.

Methods: Twenty‐three paediatric occupational therapists participated in three tutorial and video demonstrations, which were then followed by a group interview.

Results and Conclusion: Thematic analysis of transcripts identified four main themes: appropriateness of assessment tasks, language, mediation and clinical utility. Within each theme, the participants raised both positive and negative features. This paper highlights occupational therapists’ mixed views on the clinical utility of this assessment in Australia. Limitations of this study and areas for further research are suggested.
Molecular pathology of prostate cancer
Authors: Konishi Noboru , Shimada Keiji , Ishida Eiwa , Nakamura Mitsutoshi
Published: September 2005

The incidence of prostate cancer has increased in Japan recently and is developing into a life‐threatening disease for many Japanese men. This is a result of several convergent factors including the adoption of a Western lifestyle, the widespread use of prostate‐specific antigen (PSA) testing, and an increased population of advanced years in Japanese men. Although there is much information to date relating to molecular events underlying the etiology of prostate cancer, it is still unclear as to how and when these genetic alterations occur in each step of tumorigenesis. One fruitful area of investigation has been in the analysis of chromosomal abnormalities commonly observed in prostate cancer. However, no single candidate gene has been definitely identified in cancer initiation and/or progression; in addition, less research has been devoted to understanding the molecular events that underlie tumor histogenesis in terms of likely precursor lesions, such as prostatic intraepithelial neoplasia (PIN). This article reviews the current knowledge of the molecular pathology of prostate cancer, including its histogenesis, genetic and epigenetic alterations, and hereditary factors.
Cyclooxygenase‐2 expression and cell proliferation are increased in MUC2‐positive area of columnar‐lined esophagus
Authors: Jang Tae Jung , Cho Mee Yon
Published: September 2005

Columnar‐lined esophagus is composed of intestinal type and gastric type epithelium. Only the specialized or intestinal type columnar epithelium is susceptible to the development of esophageal adenocarcinoma. The aim of the present paper was to evaluate the expression of cyclooxygenase (COX) and microsomal prostaglandin E synthase (mPGES) in gastric‐type and intestinal‐type metaplasia in columnar‐lined esophagus and compare these with cell proliferation. Biopsy specimens of 30 columnar‐lined esophagus patients were collected, and immunohistochemistry was performed for secretory mucins (MUC2, MUC5AC), COX, mPGES and cell proliferation (Ki‐67). The MUC2‐positive area had higher COX‐2 expression and cell proliferation than the MUC5AC‐positive area. There was a close correlation between COX‐2 expression and cell proliferation. In contrast, the expression of COX‐1, mPGES‐1 and ‐2 was similar between intestinal metaplasia and gastric metaplasia. In conclusion, intestinal‐type columnar‐lined esophagus possesses COX‐2 expression and a higher proliferation potential, suggesting that esophageal adenocarcinoma may arise from specialized columnar‐lined esophagus.
Establishment and characterization of a human colonic mucinous carcinoma cell line with predominant goblet‐cell differentiation from liver metastasis
Authors: Yamachika Takasuke , Nakanishi Hayao , Yasui Kenzo , Ikehara Yuzuru , Niwa Toru , Wanibuchi Hideki , Tatematsu Masae , Fukushima Shoji
Published: September 2005

Many human colorectal adenocarcinoma cell lines have been developed. However, differentiated type colorectal cancer cell lines, particularly, the goblet‐cell differentiated type, are scarce. In the present study a novel colorectal adenocarcinoma cell line (designated as COLM‐6) with predominant goblet‐cell differentiation was established from the rectal mucinous adenocarcinoma of a Japanese woman. COLM‐6 cells grow in a typical epithelial monolayer in culture. They expressed epidermal growth factor (EGF) receptor and HER2 on their surface and accordingly, their growth was significantly stimulated by EGF, transforming growth factor (TGF)‐α and heregulin. COLM‐6 cells form tumor with typical mucinous adenocarcinomatous appearance in nude mice. Immunohistochemical analysis of these subcutaneous tumors demonstrated that COLM‐6 cells strongly express MUC2 as a goblet‐cell marker and Cdx2 in the nucleus. Some weakly express villin and carbonic anhydrase 1 as a columnar absorptive‐cell marker as well. They were also positive for adenomatous polyposis coli (APC) cytoplasmically and expressed β‐catenin in their cytoplasm and cell membrane without nuclear accumulation. These results indicate that COLM‐6 cell line has unique characteristics and may provide a useful tool to study the mechanism of growth and differentiation of colonic epithelium as well as the biological behavior of colorectal mucinous adenocarcinoma.
Analysis of genomic homology of murine gammaherpesvirus (MHV)‐72 to MHV‐68 and impact of MHV‐72 on the survival and tumorigenesis in the MHV‐72‐infected CB17 scid/scid and CB17+/+ mice
Authors: Oda Wakako , Mistrikova Jela , Stancekova Marta , Dutia Bernadette M. , Nash Anthony A. , Takahata Hiroyuki , Jin Zaishun , Oka Takashi , Hayashi Kazuhiko
Published: September 2005

Murine gammaherpesvirus (MHV)‐68‐infected mice are well‐known as models for Epstein–Barr virus (EBV)‐related lymphoproliferative diseases. MHV‐72 may be a relative of MHV‐68, but any genetic comparison between the two (except for the M7 gene) has never been reported. The genetic compositions of MHV‐72 and MHV‐68 were compared and the pathology of MHV‐72 infection studied in CB‐17 severe combined immunodeficiency (scid/scid; SCID) and CB17 wild‐type (CB17+/+) mice. The MHV‐72 DNA sequence was almost identical to MHV‐68 except for approximately 7000 bp corresponding to the MHV‐68 M1–M3 genes. Twenty‐seven of 30 MHV‐72‐infected SCID mice (90%) died from generalized infection with intranuclear viral inclusions for approximately 1 month, while MHV‐72‐infected CB17+/+ mice recovered from acute infection. Long observation and pathological study of 68 MHV‐72‐infected mice for up to 24 months revealed that the survival rate (29.4%) and survival time (21.3 months) of MHV‐72‐infected CB17+/+ mice were significantly lower (P = 0.0127) and shorter (P = 0.0065) than those of the controls (61.1% and 22.9 months), respectively. The malignancy development rate (60.3%) of the infected CB17+/+ mice was also significantly higher (P = 0.004) than those of the controls (22.2%). However, no MHV‐72 DNA was detected in the tumors of infected mice. MHV‐72 may have some tumor‐promoting effects but the tumorigenesis in infected CB17+/+ mice is different from EBV‐associated tumors.
Expression of thymidine phosphorylase in choroidal malignant melanoma associated with neovascular glaucoma
Authors: Kase Satoru , Saito Wataru , Yoshida Kazuhiko , Namba Kenichi , Osaki Mitsuhiko , Ohgami Kazuhiro , Shiratori Kenji , Kitaichi Nobuyoshi , Adachi Hironobu , Ito Hisao , Ohno Shigeaki
Published: September 2005

Reported herein is a case of 62‐year‐old man who complained of blurred vision and ocular pain in his right eye. The patient was diagnosed with choroidal melanoma complicated by neovascular glaucoma (NVG) and total retinal detachment, and he underwent enucleation of the eye. The isolated tumor was 2.5 × 2.5 cm in size. It was accompanied by intratumoral calcification, and consisted of epithelioid and spindle melanoma cells. There were a variety of microvessels in the stroma of the iris. The expression of thymidine phosphorylase (dThdPase), an angiogenic factor, was examined immunohistochemically. Cytoplasmic immunoreactivity for dThdPase was more prominent in the epithelioid cells than in spindle tumor cells. Another case of choroidal melanoma without NVG had less marked immunoreactivity. These results suggest that the production of dThdPase by melanoma cells correlates with the pathogenesis of NVG.
Tumor‐to‐tumor metastasis to a thyroid follicular adenoma as the initial presentation of a colonic adenocarcinoma
Authors: Fadare Oluwole , Parkash Vinita , Fiedler Paul N. , Mayerson Adam B. , Asiyanbola Bolanle
Published: September 2005

The incidence of thyroid involvement by metastatic disease from distant organs ranges from an average of 3.1% in surgical series to 5.3% in autopsy series. However, the metastasis of one tumor into another (traditionally referred to as ‘tumor‐to‐tumor metastasis’) is distinctly uncommon. Typically, they are identified as new manifestations or necropsy findings of a known, pre‐existing donor tumor. Herein is described the case of a 59‐year‐old woman whose thyroid nodule (a follicular adenoma) was resected and found to contain foci of a well‐differentiated adenocarcinoma with a morphologic and immunohistochemical profile consistent with origination from the lower gastrointestinal tract. Subsequent diagnostic work‐up revealed a sigmoid colon tumor with metastases to the liver. This is, to the authors’ knowledge, the first reported example of a colon adenocarcinoma whose initial clinical manifestation was  a metastasis to a thyroid neoplasm and only the third reported example of a colonic adenocarcinoma metastatic to a thyroid tumor. In a review of previously reported examples of tumor‐to‐tumor metastases involving a thyroid neoplasm as the recipient, the following features were present in the majority: (i) multifocality of the metastatic tumor aggregates; (ii) a total lack of, or only minimal amounts  of reaction (desmoplastic, inflammatory or myxoid) of the recipient tumor to the metastatic deposits; and (iii) retention of the histopathologic characteristics of the donor tumor in the metastatic deposits. In general, strikingly divergent morphologic features in an otherwise typical thyroid neoplasm should elicit a differential diagnosis that takes into consideration the possibility of metastasis.
Recurrence of bronchioloalveolar carcinoma in donor lung after lung transplantation: Microsatellite analysis demonstrates a recipient origin
Authors: Gómez‐Román J. Javier , Del Valle Clara Esparza , Zarrabeitia M. Teresa , Martínez José Cifrián , Goñi Felipe Zurbano , Lera Roberto Mons , Cuevas Jorge , Val‐Bernal J. Fernando
Published: September 2005

Bronchioloalveolar carcinoma is a distinctive subtype of pulmonary adenocarcinoma, without effective therapy, although there have recently been some attempts to use lung transplantation. However, a high post‐transplantation local recurrence rate is described with some controversy regarding the possible involved mechanisms, the main possibilities being the lymphatic spread and aerosolization. Presented herein is a case of a bilateral lung transplantation for a bilateral and pneumonic form of non‐mucinous bronchioloalveolar carcinoma in a 43‐year‐old woman. The histological analysis of mediastinal lymph nodes during surgery did not show neoplastic cells. Thirty‐five months after transplantation several nodular opacities in donor lungs were detected. Three pulmonary wedge resections were performed showing a non‐mucinous bronchioloalveolar carcinoma with the same histological characteristics as the primary. Again, the mediastinal lymph nodes were tumor free. A complete microsatellites molecular analysis was performed to compare the primary and recurrent carcinoma using capillary electrophoresis, showing that the recurrent tumor was generated in a recipient cellular clone. The absence of lymph node metastasis and the molecular evidence of the recipient origin of the neoplasm supports the contamination of the new lungs at the time of implantation as being the reason for the high incidence of recurrence after lung transplantation in this kind of disease.
Phyllodes tumor of borderline malignancy: Seven year follow up with immunohistochemical study
Authors: Tomita Tatsuo , Ren Yafei , Davis Marilyn , Tawfik Ossama
Published: September 2005

The patient was 80 years old when she initially presented with a left breast mass. Originally, a needle biopsy showed benign stromal and ductal cells. Five years later, the breast mass increased in size and a core needle biopsy showed a biphasic intraductal papillomatous tumor with cellular stroma. Eighteen months later, another biopsy was taken from the breast mass, revealing a well‐developed phyllodes tumor (PT) of borderline malignancy. One month later, a simple mastectomy was performed for this 87‐year‐old woman. Histolopathologic and immunohistochemical studies, including estrogen and progesterone receptors, Ki‐67 and p53, performed on tissues from the different biopsy specimens confirmed the progressive transition of the tumor in a 7 year period. An increase in mitotic activity was noted in the later samples. Similarly, percentages of p53‐ and Ki‐67‐positive cells were much higher in the stromal and ductal cells of the later samples compared to the original specimen. These findings support the notion that Ki‐67 and p53 immunohistochemical staining may be used as simple and practical markers for the evaluation of the malignant potential of PT.
Composite paraganglioma–ganglioneuroma of the urinary bladder
Authors: Usuda Hiroyuki , Emura Iwao
Published: September 2005

Presented herein is the case of a 73‐year‐old man, complaining of dysuria, who had a composite paraganglioma–ganglioneuroma of the urinary bladder (CPGUB). At cystoscopy a submucosal tumor was found in the urinary bladder and resected after transurethral biopsy. The levels of serum catecholamine and 24 h urinary excretion of catecholamine and vanillylmandelic acid were elevated. Grossly, the resected tumor, measuring 4 × 3 × 2.5 cm, had a brownish cut surface with no necrosis and hemorrhage. Histologically, the tumor had alternating cellular and fibrous areas. The cellular areas consisted of polygonal cells, arranged in well‐defined nests (Zellballen) and positive for Grimelius staining, with abundant amphophilic to acidophilic cytoplasm, occasionally containing eosinophilic hyaline globules and brown pigments. Although the nuclei of several polygonal cells were bizarre, mitoses and vascular invasion were not found. Fibrous areas consisted of spindle cells, resembling Schwann cell, admixed with ganglionic cells. To the authors’ knowledge, only four cases of CPGUB have been reported in the English‐language literature. Detailed reported cases and the present case showed no malignant features, such as extra‐bladder infiltration and metastasis, and no recurrence in the short length of follow up. Accumulation of long‐term follow‐up cases may provide valuable prognostic information on this composite tumor.
Constraints in implementing biological weed control: A review
Authors: GHOSHEH HANI Z.
Published: September 2005

Biological weed control is a selective, environment‐friendly process, utilizing host‐specific control agents towards targeted weeds that prevent damage to non‐target crops or native plants. The objective of biological control for weeds is not to eradicate but, rather, to regulate weed populations below levels that cause economic injury. There has been criticism that biological weed control research efforts aim to substitute one purchased input (a bioherbicide) for another (a chemical herbicide). It is essential to remember that ‘bioherbicides’ and ‘biological weed control’ are not synonymous. Biological control of weeds involves using any organism to reduce or eliminate the detrimental effects of weed populations, whereas bioherbicides utilize plant pathogens repeatedly. The integration of herbicides, both chemical and biological, into ecologically based weed management is an essential process for the sustainability of agriculture. Throughout this review, the constraints affecting the implementation of biological weed control are described. Greater understanding of the morphology, phenology and genetic diversity of targeted weeds is emphasized and the need to examine all aspects related to biocontrol agents is stressed. Improved technologies, better public support and financial aid, and more scientific interest, will all contribute to the progress of the ‘science of biological weed control’.