bluuebunny/crossref_metadata_2025 huggingface dataset:
Input‐ and subunit‐specific AMPA receptor trafficking underlying long‐term potentiation at hippocampal CA3 synapses
Authors: Kakegawa Wataru , Tsuzuki Keisuke , Yoshida Yukari , Kameyama Kimihiko , Ozawa Seiji
Published: July 2004

Hippocampal CA3 pyramidal neurons receive synaptic inputs from both mossy fibres (MFs) and associational fibres (AFs). Long‐term potentiation (LTP) at these synapses differs in its induction sites and N‐methyl‐D‐aspartate receptor (NMDAR) dependence. Most evidence favours the presynaptic and postsynaptic mechanisms for induction of MF LTP and AF LTP, respectively. This implies that molecular and functional properties differ between MF and AF synapses at both presynaptic and postsynaptic sites. In this study, we focused on the difference in the postsynaptic trafficking of α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid receptors (AMPARs) between these synapses. To trace the subunit‐specific trafficking of AMPARs at each synapse, GluR1 and GluR2 subunits were introduced into CA3 pyramidal neurons in hippocampal organotypic cultures using the Sindbis viral expression system. The electrophysiologically‐tagged GluR2 AMPARs, produced by the viral‐mediated transfer of the unedited form of GluR2 (GluR2Q), were inserted into both MF and AF postsynaptic sites in a neuronal activity‐independent manner. Endogenous Ca2+‐impermeable AMPARs at these synapses were replaced with exogenous Ca2+‐permeable receptors, and Ca2+ influx via the newly expressed postsynaptic AMPARs induced NMDAR‐independent LTP at AF synapses. In contrast, no GluR1 AMPAR produced by the gene transfer was constitutively incorporated into AF postsynaptic sites, and only a small amount into MF postsynaptic sites. The synaptic trafficking of GluR1 AMPARs was triggered by the activity of Ca2+/calmodulin‐dependent kinase II or high‐frequency stimulation to induce LTP at AF synapses, but not at MF synapses. These results indicate that MF and AF postsynaptic sites possess distinct properties for AMPAR trafficking in CA3 pyramidal neurons.
The distributed neuronal systems supporting choice‐making in real‐life situations: differences between men and women when choosing groceries detected using magnetoencephalography
Authors: Braeutigam Sven , Rose Steven P. R. , Swithenby Stephen J. , Ambler Tim
Published: July 2004

In this work, magnetoencephalography was used to study the temporal dynamics of neural responses in 16 subjects (eight women, eight men) choosing among different day‐to‐day consumer items. At short latencies (< 150 ms), the evoked responses showed striate and extrastriate cortical activation common to the processing of general objects. At about 300 ms, women activated preferentially left posterior cortices, whereas men activated preferentially right temporal cortices. This may reflect sex/gender differences in cognitive strategies, emphasizing category‐specific knowledge in women and spatial memories in men. At latencies greater than 500 ms, right parietal cortices were preferentially activated when previously bought or used items were chosen. In contrast, left inferior and right orbital cortices were preferentially activated when selecting less‐known items. This may be interpreted as representing the neural correlates of decisions where the outcome is consistent with previous experience, and of choices which are ‘difficult’ in some sense. Analysis of coherent γ‐oscillations (20–45 Hz) revealed neural activity over left anterior and right dorsolateral cortices at long latency (> 1500 ms) when brand knowledge is low. This is consistent with the late binding of (brand) memories and evaluation of multiple sources of information when a choice is not obvious. γ‐Activity showed that women may activate larger neural networks when preference is high, suggesting that men and women exhibit different patterns of neural activity even though their overt performances are similar.
Both d‐ and l‐glutamate induce transporter‐mediated presynaptic autoinhibition of transmitter release
Authors: Dudel Josef
Published: July 2004

In crayfish motor nerve terminals l‐glutamate (Glu) is the excitatory transmitter and low l‐Glu concentrations exert autoinhibition by inhibiting release of Glu quanta from the terminals. This autoinhibition has been shown to be mediated by binding and transport of l‐Glu by Glu transporters in the presynaptic membrane. Activated transporters open an associated Cl– channel and inhibit release [J. Dudel & M. Schramm (2003) Eur. J. Neurosci., 18, 902–910]. The excitatory, glutamatergic synaptic transmission is specific for the l‐Glu isomer. However, transporters are non‐selective for the stereoisomers. It is shown here that low concentrations (5 µm) of d‐ as well as l‐Glu inhibit quantal release on average to 55 and 68%, respectively. The power of inhibition varies widely at different terminals but the local sensitivity to d‐Glu is seen to be the same as that for l‐Glu. l‐Glutamate has been reported to reduce the mean amplitude of nerve terminal action currents (excitatory nerve terminal currents) by about 10%, presumably due to the opening of Cl– channels. Evidence is given that d‐Glu also inhibits this by an average of 10% (P < 0.001), as expected if both l‐ and d‐Glu activate a transporter‐associated Cl– conductance. The results give further support for this novel mechanism of regulation of synaptic strength.
Impaired behavioural flexibility and memory in mice lacking GDNF family receptor α2
Authors: Võikar Vootele , Rossi Jari , Rauvala Heikki , Airaksinen Matti S.
Published: July 2004

The glial cell line‐derived neurotrophic factor (GDNF) family receptor GFRα2 is the binding receptor for neurturin (NRTN). The main biological responses of GFRα2 are mediated via the Ret receptor tyrosine kinase, although it may also signal independently of Ret via the neural cell adhesion molecule NCAM. GFRα2 is expressed in many neurons of both the central and peripheral nervous system. Mice lacking GFRα2 receptors do not exhibit any gross defects in the central nervous system structure. However, they display profound deficits in the parasympathetic and enteric nervous system, accompanied by significant reduction in body weight after weaning. Here we present the results of behavioural analysis of the GFRα2‐knockout mice. The knockout mice did not differ from wild‐type mice in basic tests of motor and exploratory activity. However, differences were established in several memory tasks. The knockout mice were not impaired in the acquisition of spatial escape strategy. However, the deficit in flexibility in establishing a new strategy was revealed during reversal learning with the platform in the opposite quadrant of the pool. Furthermore, the knockout mice displayed significant impairment in contextual fear conditioning and conditioned taste aversion tests of memory. The results suggest that GFRα2 signalling plays a role in the development or maintenance of cognitive abilities that help in solving complex learning tasks.
Microstimulation of V1 delays the execution of visually guided saccades
Authors: Tehovnik Edward J. , Slocum Warren M. , Schiller Peter H.
Published: July 2004

Electrical stimulation delivered to V1 concurrently with the presentation of a visual target interferes with both the selection and the detection of targets positioned in the receptive field of the stimulated neurons. In the present study, we examined the temporal course of this effect by delivering electrical stimulation to V1 of rhesus monkeys at various times before the appearance of a visual target. Each trial was initiated by the appearance of a fixation spot that, once acquired, was followed by the presentation of a visual target in the receptive field of the stimulated neurons. A monkey was reward after making a saccadic eye movement to the target. A delay in saccade generation was obtained when stimulation was delivered while an animal maintained fixation on the fixation spot. No delay occurred when the visual target was placed outside the receptive field of the stimulated neurons. The best parameters for inducing the saccadic delay were: (i) anode‐first pulses (as opposed to cathode‐first pulses) and (ii) train durations greater than 40 ms and frequencies greater than 100 Hz. The lowest current threshold for producing a saccadic delay occurred at 1.5 mm below the top of superficial V1. The chronaxies of the directly stimulated elements mediating the delay ranged from 0.13 to 0.24 ms. These values overlap with those that have been described for phosphene induction in human V1. We discuss how the elements mediating the saccadic delay might interrupt a visual signal as it passes along the geniculostriate pathway.
Temporary cyst formation in phytoplankton: a response to allelopathic competitors?
Authors: Fistarol Giovana O. , Legrand Catherine , Rengefors Karin , Granéli Edna
Published: July 2004

Competition among phytoplankton for limiting resources may involve direct or indirect interactions. A direct interaction of competitors is the release of chemicals that inhibit other species, a process known as allelopathy. Here, we investigated the allelopathic effect of three toxic microalgae species (Alexandrium tamarense, Karenia mikimotoi and Chrysochromulina polylepis) on a natural population of the dinoflagellate Scrippsiella trochoidea. Our major findings were that in addition to causing death of S. trochoidea cells, the allelopathic species also induced the formation of temporary cysts in S. trochoidea. Because cysts were not lysed, encystment may act as a defence mechanism for S. trochoidea to resist allelochemicals, especially when the allelopathic effect is moderate. By forming temporary cysts, S. trochoidea may be able to overcome the effect of allelochemicals, and thereby have an adaptive advantage over other organisms unable to do so.
Bacterial diversity in marine hydrocarbon seep sediments
Authors: LaMontagne Michael G. , Leifer Ira , Bergmann Sandra , Van De Werfhorst Laurie C. , Holden Patricia A.
Published: July 2004

Marine seeps introduce significant amounts of hydrocarbons into oceans and create unusual habitats for microfauna and ‐flora. In the vicinity of chronic seeps, microbes likely exert control on carbon quality entering the marine food chain and, in turn, hydrocarbons could influence microbial community composition and diversity. To determine the effects of seep oil on marine sediment bacterial communities, we collected sediment piston cores within an active marine hydrocarbon seep zone in the Coal Oil Point Seep Field, at a depth of 22 m in the Santa Barbara Channel, California. Cores were taken adjacent to an active seep vent in a hydrocarbon volcano, on the edge of the volcano, and at the periphery of the area of active seepage. Bacterial community profiles were determined by terminal restriction fragment length polymorphisms (TRFLPs) of 16S ribosomal genes that were polymerase chain reaction (PCR)‐amplified with eubacterial primers. Sediment carbon content and C/N ratio increased with oil content. Terminal restriction fragment length polymorphisms suggested that bacterial communities varied both with depth into sediments and with oil concentration. Whereas the apparent abundance of several peaks correlated positively with hydrocarbon content, overall bacterial diversity and richness decreased with increasing sediment hydrocarbon content. Sequence analysis of a clone library generated from sediments collected at the periphery of the seep suggested that oil‐sensitive species belong to the γ Proteobacteria and Holophaga groups. These sequences were closely related to sequences previously recovered from uncontaminated marine sediments. Our results suggest that seep hydrocarbons exert a strong selective pressure on bacterial communities in marine sediments. This selective pressure could, in turn, control the effects of oil on other biota in the vicinity of marine hydrocarbon seeps.
Analysis and glycosyl composition of the exopolysaccharide isolated from the floc‐forming wastewater bacterium Thauera sp. MZ1T
Authors: Allen Michael S. , Welch Karen T. , Prebyl Benjamin S. , Baker David C. , Meyers Arthur J. , Sayler Gary S.
Published: July 2004

Conditions were developed for the reproducible production, isolation and characterization of a novel microbial extracellular polysaccharide believed to be involved in transient viscous bulking at an industrial wastewater treatment plant. The exopolysaccharide was extracted from cell‐free culture supernatants of Thauera sp. strain MZ1T grown on a minimal medium with succinate. The purified polymer was found to be approximately 260 kDa in size by gel‐permeation chromatography. The GC–MS analysis of the alditol acetate and per‐O‐trimethylsilyl methyl glycoside derivatives revealed that the exopolysaccharide was composed of four monosaccharides including: rhamnose, galacturonic acid, N‐acetylglucosamine and N‐acetylfucosamine. Glucose, which also appeared at low levels, is most likely from a co‐eluting glucan. The FTIR and NMR spectroscopic analyses further revealed the presence of esterified component groups on the polymer. These results represent the first published description of a polysaccharide from a member of the genus Thauera, and lay the foundation for a deeper understanding of the factors potentially involved in zoogloeal cluster formation and viscous bulking.
Diversity of the archaeal community in 44 anaerobic digesters as determined by single strand conformation polymorphism analysis and 16S rDNA sequencing
Authors: Leclerc Marion , Delgènes Jean‐Philippe , Godon Jean‐Jacques
Published: July 2004

The diversity of Archaea in anaerobic digesters was characterized by strand conformation polymorphism (SSCP) analysis and the sequencing of 16S rDNA genes. The 44 digesters sampled, located in eight different countries, treated effluents from agriculture, the food processing and petro‐chemical industries, pulp and paper plant, breweries, slaughterhouses and municipal waste. All the existing processes were represented among the samples (fixed‐film, fluidized bed, stirred‐tank, UASB, sequential batch reactor, lagoon). Single strand conformation polymorphism analysis targeting the V3 region of 16S rDNA revealed between four to six distinct archaeal peaks per digester. The diversity of dominant Archaea in the 44 digesters was estimated as 23 different 16S rDNA sequences. Cloning of archaeal 16S rRNA genes from 11 distinct total genomic DNA, screening of clones by SSCP and the sequencing of 170 of them made it possible to characterize these SSCP peaks. All the sequences retrieved were members of the Euryarchaeaota subdomain. Furthermore, most of the sequences retrieved were very close to already known and cultivated strains or to environmental clones. The most frequent archaeal sequences were close to Methanosaeta concilii and to a 16S rDNA clone vadinDC06 located in the Methanobacterium clade (84% and 73% of digesters respectively). The other sequences were members of the Methanobacteriales and the Methanomicrobiales families. Only one sequence was far from any sequence of the database and it could be grouped with several sequences of environmental clones. Each digester harboured between two to nine archaeal sequences with only one of them corresponding to a putative acetate‐utilizing species. Furthermore, the process in the digesters appeared to play a part in the distribution of archaeal diversity.
Abundance of active and inactive microcystin genotypes in populations of the toxic cyanobacterium Planktothrix spp.
Authors: Kurmayer Rainer , Christiansen Guntram , Fastner Jutta , Börner Thomas
Published: July 2004

To investigate the abundance of active and inactive microcystin genotypes in populations of the filamentous cyanobacterium Planktothrix spp., individual filaments were grown as clonal strains in the laboratory and analysed for microcystin synthetase (mcy) genes and microcystin. Twenty‐three green‐pigmented strains of P. agardhii originating mostly from shallow water bodies fell into two groups, those possessing mcyA and those lacking mcyA. In contrast, all of the 49 strains that were assigned to the red‐pigmented P. rubescens contained mcyA. One strain of P. agardhii and eight strains of P. rubescens contained the total microcystin synthetase gene cluster but were found inactive in microcystin synthesis. To investigate the natural abundance of inactive mcy genotypes in P. rubescens individual filaments sampled from Lake Irrsee and Lake Mondsee (Austria) were analysed directly for the presence of mcyA and microcystin by matrix‐assisted laser desorption/ionisation time‐of‐flight mass spectrometry. All filaments assigned to P. rubescens contained mcyA. The proportion of inactive microcystin genotypes in populations with a low (Irrsee) or high density (Mondsee) of P. rubescens was 5% and 21%, each. The results of this study demonstrate that P. rubescens typically contain mcy genes whereas P. agardhii have a patchy distribution of mcy genes. In both species microcystin producers co‐occur with non‐microcystin producers due to the absence/inactivation of mcy genes.
Differential response of archaeal and bacterial communities to nitrogen inputs and pH changes in upland pasture rhizosphere soil
Authors: Nicol Graeme W. , Webster Gordon , Glover L. Anne , Prosser James I.
Published: July 2004

Grassland management regimens influence the structure of archaeal communities in upland pasture soils, which appear to be dominated by as yet uncultivated non‐thermophilic Crenarchaeota. In an attempt to determine which grassland management factors select for particular crenarchaeal community structures, soil microcosm experiments were performed examining the effect of increased pH, application of inorganic fertilizer (ammonium nitrate) and sheep urine deposition on both archaeal and bacterial communities in unmanaged grassland soil. As grassland management typically increases pH, a further experiment examined the effect of a reduction in pH, to that typical of unimproved grassland soils, on archaeal and bacterial communities. The RT‐PCR amplification of 16S rRNA followed by denaturing gradient gel electrophoresis analysis demonstrated a distinct and reproducible effect on bacterial communities after incubation for 28 or 30 days. In contrast, none of the treatments had a significant effect on the structure of the crenarchaeal community, indicating that these factors are not major drivers of crenarchaeal community structures in grassland soils.
From PCBs to highly toxic metabolites by the biphenyl pathway
Authors: Cámara Beatriz , Herrera Cristina , González Myriam , Couve Eduardo , Hofer Bernd , Seeger Michael
Published: July 2004

The degradation of polychlorobiphenyls (PCBs) by diverse bacteria, including Burkholderia sp. LB400, is incomplete with a concomitant accumulation of metabolic intermediates. In this study, the toxicity of diverse (chloro)biphenyls and of their biotransformation into the first two metabolic intermediates of the biphenyl pathway, were determined for the model bacterium Escherichia coli. Recombinant E. coli strains expressing different subsets of bph genes of strain LB400 accumulated metabolic intermediates from (chloro)biphenyls. During biotransformation of these compounds into metabolic intermediates, the viability and metabolic kinetics were determined. The toxicity of biotransformation of (chloro)biphenyls into different metabolic intermediates of (chloro)biphenyls varied. Dihydrodiols and dihydroxybiphenyls are very toxic metabolites for bacteria even after short incubation times, affecting the cell viability much more than (chloro)biphenyls. When bacteria transformed 2‐CB into dihydrodiol or dihydroxybiphenyl, a great decrease of intact cells and abundant cell lysis was observed by transmission electronic microscopy. Cell viability of Burkholderia sp. LB400 and of E. coli exposed directly to 2,3‐dihydroxybiphenyl decreased also drastically. The toxicity of metabolites generated during oxidation of PCBs may partly explain the recalcitrance to biodegradation of these pollutants. Conversion of less toxic compounds into products with increased toxicity resembles the bioactivation of xenobiotics in higher organisms.
Salmonella diversity associated with wild reptiles and amphibians in Spain
Authors: Briones Víctor , Téllez Sonia , Goyache Joaquín , Ballesteros Cristina , Del Pilar Lanzarot María , Domínguez Lucas , Fernández‐Garayzábal José F.
Published: July 2004

During the spring and summer of 2001, faeces from 166 wild reptiles (94 individuals) and amphibians (72 individuals) from 21 different species found in central Spain were examined for the presence of Salmonella. Thirty‐nine reptiles (41.5%) yielded 48 Salmonella isolates, whereas all the amphibians examined were negative. Subspecies Salmonella enterica enterica (I) accounted for up to 50% of isolates. Fourteen isolates (29.2%) belonged to subspecies diarizonae (IIIb), six isolates (12.5%) to subspecies salamae (II), and four isolates (8.3%) to subspecies arizonae (IIIa). Twenty‐seven different serotypes were identified. Serotypes Anatum (12.5%), Herzliya (8.3%), Abony, 18:l,v:z, 9,12:z29:1,5 and 38:z10:z53 (6.2%/each) were the most frequently isolated. A high percentage (39.6%) of isolates belonged to serotypes previously associated with environmental sources. Also, 37.5% of isolates belonged to serotypes which had been related to human cases of salmonellosis. From these data, it is concluded that wild reptiles, but apparently not amphibians, may represent an important reservoir of Salmonella in nature and have potential implications for public health.
Mechanism of chromate reduction by the Escherichia coli protein, NfsA, and the role of different chromate reductases in minimizing oxidative stress during chromate reduction
Authors: Ackerley D. F. , Gonzalez C. F. , Keyhan M. , Blake R. , Matin A.
Published: July 2004

Chromate [Cr(VI)] is a serious environmental pollutant, which is amenable to bacterial bioremediation. NfsA, the major oxygen‐insensitive nitroreductase of Escherichia coli, is a flavoprotein that is able to reduce chromate to less soluble and less toxic Cr(III). We show that this process involves single‐electron transfer, giving rise to a flavin semiquinone form of NfsA and Cr(V) as intermediates, which redox cycle, generating more reactive oxygen species (ROS) than a divalent chromate reducer, YieF. However, NfsA generates less ROS than a known one‐electron chromate reducer, lipoyl dehydrogenase (LpDH), suggesting that NfsA employs a mixture of uni‐ and di‐valent electron transfer steps. The presence of YieF, ChrR (another chromate reductase we previously characterized), or NfsA in an LpDH‐catalysed chromate reduction reaction decreased ROS generation by c. 65, 40, or 20%, respectively, suggesting that these enzymes can pre‐empt ROS generation by LpDH. We previously showed that ChrR protects Pseudomonas putida against chromate toxicity; here we show that NfsA or YieF overproduction can also increase the tolerance of E. coli to this compound.
Diversity and ecology of soil fungal communities: increased understanding through the application of molecular techniques
Authors: Anderson Ian C. , Cairney John W. G.
Published: July 2004

Fungi fulfil a range of important ecological functions, yet current understanding of fungal biodiversity in soil is limited. Direct DNA extraction from soil, coupled with polymerase chain reaction amplification and community profiling techniques, has proved successful in investigations of bacterial ecology and shows great promise for elucidating the taxonomic and functional characteristics of soil fungal communities. These community profiling techniques include denaturing gradient gel electrophoresis (DGGE), temperature gradient gel electrophoresis (TGGE), single‐strand conformation polymorphism (SSCP), terminal restriction fragment length polymorphism (T‐RFLP), amplified rDNA restriction analysis (ARDRA), amplified ribosomal intergenic spacer analysis (ARISA) and cloning, and are generally coupled with DNA sequencing. The techniques and their potential limitations are discussed, along with recent advances that have been made possible through their application in soil fungal ecology. It is unlikely that a single approach will be universally applicable for assessing fungal diversity in all soils or circumstances. However, judicious selection of the methodology, keeping the experimental aims in mind, and the exploitation of emerging technologies will undoubtedly increase our understanding of soil fungal communities in the future.
When theory abandons us – wading through the ‘swampy lowlands’ of practice
Authors: Rycroft Pam
Published: July 2004

This paper uses three clinical examples to illustrate the experience of feeling abandoned by theory – times when no one model has sufficient signposts to show the way. Therapy is considered to be an endlessly creative interpersonal encounter, to which the client brings the major resource for change. It is argued that the therapist is influenced by worldview, values and beliefs, and personal style, as well as by theoretical model. Further, it is suggested that there is a need to acknowledge and investigate the limitations of therapy. An argument is made for ‘going beyond the model’, for seeking an ethical practice based on what our clients tell us is important, and for sharing across models the common dilemmas and goals of therapy. Clinicians are encouraged to articulate their own ‘swampy lowland’ principles of practice.
The implementation of contextual therapy in the therapeutic community for substance abusers: a case study
Authors: Soyez Veerle , Tatrai Hilde , Broekaert Eric , Bracke Rudy
Published: July 2004

Family therapy takes a special position in the therapeutic community for substance abusers (TC). In the early therapeutic communities, the family of origin was not considered as important for the substance abuser's recovery process, and was even labelled as part of the problem. It was only in the 1970s that the TC acknowledged the significance of family involvement in treatment. Nowadays, the contextual vision of Ivan‐Boszormenyi‐Nagy seems to have a strong impact on family counselling activities in Belgian TCs.

In this article, the integration of contextual thinking in the TC is discussed. By means of a case study, it is shown that there are some clear parallels between the treatment evolutions in family counselling and the peer group community. The central position of trust both in contextual therapy and the TC treatment model is an important common ground for stimulating integration. Some obstacles that can disrupt this integration process are discussed.
Obesity, adipocytokines, and insulin resistance in breast cancer
Authors: Rose D. P. , Komninou D. , Stephenson G. D.
Published: July 2004

The adipocytokines are biologically active polypeptides that are produced either exclusively or substantially by the adipocytes, and act by endocrine, paracrine, and autocrine mechanisms. Most have been associated with obesity, hyperinsulinaemia, type 2 diabetes, and chronic vascular disease; in addition, six adipocytokines – vascular endothelial growth factor, hepatocyte growth factor, leptin, tumour necrosis factor‐alpha, heparin‐binding epidermal growth factor‐like growth factor, and interleukin‐6 – promote angiogenesis while one, adiponectin, is inhibitory. Obesity and insulin resistance have both been identified as risk factors for breast cancer and are associated with late‐stage disease and poor prognosis. Angiogenesis is essential for breast cancer development and progression, and so it is plausible that obesity‐related increases in adipocytokine production and a reduction in adiponectin may adversely affect breast cancer outcome by their angiogenesis‐related activities. There is also experimental evidence that some adipocytokines can act directly on breast cancer cells to stimulate their proliferation and invasive capacity. Thus, adipocytokines may provide a biological mechanism by which obesity and insulin resistance are causally associated with breast cancer risk and poor prognosis. Both experimental and clinical studies are needed to develop this concept, and particularly in oestrogen‐independent breast cancers where preventive and therapeutic options are limited.
Obesity as a disease: no lightweight matter
Authors: Conway B. , Rene A.
Published: July 2004

The epidemic rise in obesity has fuelled the current debate over its classification as a disease. Contrary to just being a medical condition or risk factor for other diseases, obesity is a complex disease of multifaceted aetiology, with its own disabling capacities, pathophysiologies and comorbidities. It meets the medical definition of disease in that it is a physiological dysfunction of the human organism with environmental, genetic and endocrinological aetiologies. It is a response to environmental stimuli, genetic predisposition and abnormalities, and has a characteristic set of signs and symptoms with consistent anatomical alterations. Excess adipose tissue increases the work of the heart and leads to anatomical changes in this organ. It alters pulmonary, endocrine and immunological functions, all with adverse effects on health. Some of the complications of obesity include cardiovascular disease, non‐insulin‐dependent diabetes mellitus, obstructive pulmonary disease, arthritis and cancer. Given the excess mortality, substantial morbidity and the economic toll of obesity, this is a disease that warrants serious attention by the medical community. Obesity's status and acceptance as a disease is pivotal in determining its treatment, reimbursement for treatment and the development of widespread interventions.
Super‐ordinary bias in Japanese self‐predictions of future life events
Authors: Ohashi Megumi M. , Yamaguchi Susumu
Published: July 2004

Japanese are said to value being ordinary and emphasize similarity with others. We theorized that Japanese tend to perceive themselves as being ordinary, so much so that their self‐predictions about future life events are biased (super‐ordinary bias). Specifically, it was expected that Japanese overestimate the likelihood of experiencing common events (such as getting married or catching the flu) and underestimate the likelihood of experiencing rare events (such as winning a lottery or being murdered). We examined the effects of commonness and desirability of future life events on the relative‐likelihood estimates. Our expectation was supported by three studies, involving a questionnaire, a laboratory experiment, and a mail survey. Findings are consistent with the assumed tendency to view oneself as being super‐ordinary. The super‐ordinary bias was also found to be independent of unrealistic optimism or pessimism.
Book Review
Authors: Wan Ching
Published: July 2004

Book reviewed in this article:

Colleen Ward, Stephen Bochner and Adrian Furnham (eds.), The Psychology of Culture Shock, second edition
Rugged Plateaus and Extensive Floodplains — Modelling Landform Evolution in a Northern Australian Catchment
Authors: Boggs G.S. , Evans K.G. , Devonport C.C.
Published: July 2004

Medium to large natural catchments are often more spatially heterogeneous than small catchments or single landforms. Attempting to model landform evolution of large areas is consequently more complex. This paper demonstrates that modelling landform evolution in medium to large catchments can be improved by calibrating the model to smaller, more geomorphologically homogenous sub‐catchments. The paper investigates landform evolution in the Ngarradj catchment in the Northern Territory of Australia (a medium scale catchment of approximately 67 km2). The catchment is complex and contains two distinct landform regions; an upland plateau region with highly dissected sandstone and shallow, sandy soils, and a lowlands region with gentle, wooded slopes and floodplains with deep, sandy soils. The SIBERIA landform evolution model is calibrated and applied to the Ngarradj catchment. The complexity of the Ngarradj catchment is incorporated into the modelling by dividing the catchment into three sub‐catchments (Swift Creek (SC), Upper Main (UM) and East Tributary (ET)) which are relatively homogeneous and for which hydrology and sediment transport data are available. A discharge‐area relationship and long‐term, sediment loss rates for the catchment are derived based on an annual series flood frequency analysis of a 20 year runoff record predicted in a previous study. Sediment transport modelling incorporates both suspended and bedload sediment loss. The denudation rates derived using these data are 37, 63 and 77 mm kyr−1 for the SC, UM and ET sub‐catchments, respectively. Model predictions indicate that the UM sub‐catchment will have the greatest mean erosion. This is balanced by the large amount of deposition that will occur in the upper Ngarradj valley of the UM sub‐catchment. Further deposition occurs on the floodplain of Ngarradj, with the area between the SC and ET/UM (up‐stream) sub‐catchments experiencing a small net accretion of sediment (15 mm kyr−1).
Wired Communities in the City: Sydney, Australia
Authors: Baum Scott , Van Gellecum Yolanda , Yigitcanlar Tan
Published: July 2004

Questions relating to the ability of particular groups in society to access information and communications technologies (ICTs) have become a growing part of the academic and policy literature. The issues raised in this literature have revolved around a number of themes, many of which can be subsumed under concerns about a growing digital divide whereby society is being divided into information rich and information poor sectors. This differentiation can be between particular social groups irrespective of place, or between people in particular places be these large regional areas (e.g. metropolitan versus non‐metropolitan) or localities and communities within an urban area. This paper focuses on the existence of a ‘digital divide’ across the Sydney metropolitan area. Using ABS 2001 census data the paper presents an analysis of computer and internet access and use for clusters of local communities and focuses on how usage differs across communities as differentiated by socio‐economic status, household and family status and ethnic background.
Characterizing Pareto Improvements   in an Interdependent Demand System
Authors: Kooreman Peter , Schoonbeek Lambert
Published: July 2004

Interdependent preferences generally imply Pareto inefficiency. For a general demand system, we provide a characterization of Pareto improvements. For a prominent parametric specification, the Linear Expenditure System, we characterize in detail the welfare loss associated with interdependent preferences. Using an estimated empirical model of this kind, we calculate the compensating variation corresponding to the welfare loss.
Optimal Income Maintenance and the “Unemployable”
Authors: Leblanc Greg
Published: July 2004

This paper examines optimal income maintenance policy with asymmetric information about individuals' abilities. A minimum skill level is required for employment. The unemployable are those (low) ability types who find this minimum investment too costly. To guarantee some minimum income level, the government chooses between welfare, workfare, earnings subsidies, and training. Results show that the optimal scheme entails training. Moreover, though complex separating mechanisms are both feasible and encourage investments in skills, the least‐cost income maintenance scheme is quite simple: the government offers training at the lowest level consistent worth employment to all who want it.
Was Wittgenstein an Analytic Philosopher?
Authors: Glock Hans‐Johann
Published: July 2004

Abstract: This article first surveys the established views on Wittgenstein's relation to analytic philosophy. Next it distinguishes among different ways of defining analytic philosophy—topical, doctrinal, methodological, stylistic, historical, and the idea that it is a family‐resemblance concept. It argues that while certain stylistic features are important, the historical and the family‐resemblance conceptions are the most auspicious, especially in combination. The answer to the title question is given in section 3. Contrary to currently popular “irrationalist” interpretations, Wittgenstein was an analytic philosopher in all phases of his career, albeit an exceedingly exotic one whose style transcends the limits of academic philosophy in general. On the historical understanding he qualifies because he was influenced by and in turn influenced mainly analytic philosophers. On the family‐resemblance conception he qualifies both because he developed and employed logico‐linguistic analysis and because he initiated the linguistic turn and the distinction between philosophy and science that characterizes one important strand in analytic philosophy.
On the Structure of Twentieth‐Century Philosophy
Authors: Rockmore Tom
Published: July 2004

Abstract: It makes sense to ask from time to time where we are in the philosophical discussion. This article reviews the debate in the twentieth century. Michael Friedman has recently argued that the split between Continental and analytic philosophy is due to the inability, because of war, to carry forward a genuine debate begun by Heidegger and Carnap around the time of Heidegger's public controversy with Cassirer at Davos in 1929. I, however, argue that there was not even the beginning of a genuine debate between Heidegger and Carnap. I argue further that the split between analytic and Continental philosophy originated earlier, in the analytic attack on idealism at the beginning of the century. And finally I argue that the differences among analytic philosophy, Continental philosophy, and pragmatism, the third main current of twentieth‐century philosophy, can be traced to differing reactions to Kant.
Logical Positivism, Analytic Method, and Criticisms of Ethnophilosophy
Authors: Ikuenobe Polycarp
Published: July 2004

Abstract: I argue that the analytic method has been circularly used to analyze the concept of “philosophy,” and that the result of this analysis has also been used to criticize African ethnophilosophy as nonphilosophical. I critically examine the criticism that ethnophilosophy implies cognitive relativism and the criticism that it implies authoritarianism. I defend ethnophilosophy against these criticisms, arguing that they are rooted in logical positivism, the view that philosophy essentially involves the use of the methods of science and logical analysis. I argue that such analysis and criticisms, given their pedigree, do not provide an adequate or accurate picture of the nature of philosophy.
Epistemological Metaphors and the Nature of Philosophy
Authors: Thagard Paul , Beam Craig
Published: July 2004

Abstract: This article examines some of the most important metaphors and analogies that epistemologists have used to discuss the structure and validity of knowledge. After reviewing foundational, coherentist, and other metaphors for knowledge, we discuss the metaphilosophical significance of the prevalence of such metaphors. We argue that they support a view of philosophy as akin to science rather than poetry or rhetoric.
The Metaphysics of Personal Identity and Our Special Concern for the Future
Authors: Kind Amy
Published: July 2004

Abstract: Philosophers have long suggested that our attitude of special concern for the future is problematic for a reductionist view of personal identity, such as the one developed by Derek Parfit in Reasons and Persons. Specifically, it is often claimed that reductionism cannot provide justification for this attitude. In this article, I argue that much of the debate in this arena involves a misconception of the connection between metaphysical theories of personal identity and our special concern. A proper understanding of this connection reveals that the abovementioned objection to reductionism cannot get off the ground. Though the connection I propose is weaker than the connection typically presupposed, I nonetheless run up against a conclusion reached by Susan Wolf in “Self‐Interest and Interest in Selves.” According to Wolf, metaphysical theses about the nature of personal identity have no significance for our attitude of special concern. By arguing against Wolf's treatment of self‐interest, I suggest that her arguments for this conclusion are misguided. This discussion leads to further clarification of the nature of the link between theories of personal identity and our special concern and, ultimately, to a better understanding of the rationality of this attitude.
Open Problems in the Philosophy of Information
Authors: Floridi Luciano
Published: July 2004

Abstract:The philosophy of information (PI) is a new area of research with its own field of investigation and methodology. This article, based on the Herbert A. Simon Lecture of Computing and Philosophy I gave at Carnegie Mellon University in 2001, analyses the eighteen principal open problems in PI. Section 1 introduces the analysis by outlining Herbert Simon's approach to PI. Section 2 discusses some methodological considerations about what counts as a good philosophical problem. The discussion centers on Hilbert's famous analysis of the central problems in mathematics. The rest of the article is devoted to the eighteen problems. These are organized into five sections: problems in the analysis of the concept of information, in semantics, in the study of intelligence, in the relation between information and nature, and in the investigation of values.
Hepatic pathology in AIDS: a pathological study from Mumbai, India
Authors: Lanjewar DN , Rao RJ , Kulkarni SB , Hira SK
Published: July 2004

Objectives

To assess the spectrum of hepatic disorders in AIDS, liver specimens from 171 patients (155 autopsies and 16 biopsies) were reviewed.

Methods

A retrospective and prospective study of 171 autopsy and biopsy specimens was carried out at a tertiary level hospital in Mumbai, India.

Results

Of the patients included in the study, 127 (74%) were male and 44 (26%) were female. The heterosexual route was the predominant mode of HIV transmission, identified in 163 (95%) patients. A total of 99 of 171 patients (58%) showed significant pathological lesions, and the most common pathological processes involving the liver appeared to be secondary to infections. None of our patients showed isolated infectious diseases of the liver. The spectrum of liver diseases identified was as follows: tuberculosis in 70 patients (41%), cryptococcosis in eight (5%), cytomegalovirus infection in six (3%), hepatitis B infection in five (3%), candidiasis in one (0.5%), malaria in one (0.5%), cirrhosis in six (3%), amyloidosis in one (0.5%) and primary hepatic lymphoma in one (0.5%).

Conclusions

AIDS patients were found to have a high prevalence of underlying hepatic abnormalities. The spectrum of disease among patients with AIDS in India differs from that in developed countries. Our results suggest that hepatic tuberculosis is more common in AIDS than previously recognized, and that liver specimens should be examined routinely for the presence of acid‐fast bacilli.
Efficacy, safety and predictive factors of virological success of a boosted amprenavir‐based salvage regimen in heavily antiretroviral‐experienced HIV‐1‐infected patients
Authors: Clevenbergh P , Boulmé R , Kirstetter M , Dellamonica P
Published: July 2004

Background

Amprenavir (APV) has been shown to be effective in naive or treatment‐experienced HIV‐1 infected patients. However, the safety and efficacy of the APV 600 mg/ritonavir (RTV) 100 mg twice a day (bid) combination, the usually recommended dosage for boosted APV, have been less well studied. We assessed the predictive factors associated with virological success of APV/RTV‐based regimens.

Methods

Patients in the PharmAdapt study receiving an APV/RTV‐containing regimen were included in the study. The predictivity of covariates on virological response at 4 months was analysed according to the data analysis plan. We processed logistic regression using bootstrapping to allow several covariates in the models.

Results

Forty patients received an APV/RTV‐containing regimen, 38 of whom were male (95%). Risk factors were heterosexual contacts (four patients; 10%), homosexual contacts (31 patients; 78%), and intravenous drug use (four patients; 10%). Twenty‐seven per cent of patients were Centers for Disease Control and Prevention Classification System (CDC) stage A, 38% were stage B and 35% were stage C. The median baseline CD4 count was 313 cells/μL [interquartile range (IQR) 211, 414], and the median baseline viral load was 4.4 log10 HIV‐1 RNA copies/mL (IQR 3.7, 4.9). Patients were exposed to a median number of 7.5 (IQR 6, 9) drugs for a median number of 3.8 (IQR 3.3, 4.3) years. The baseline number of resistance mutations was 4 [IQR 3, 5 for nucleoside reverse transcriptase inhibitors (NRTIs), 1 (IQR 0, 2)] for non‐nucleoside reverse transcriptase inhibitors (NNRTIs) and 6 [IQR 5, 8 for protease inhibitors (PIs)]. At month 4, median viral load decreased to 1.2 log10 copies/mL (IQR 0.3, 1.6); 50% of patients had a viral load<200 copies/mL by intention‐to‐treat analysis. The number of APV resistance mutations was associated with viral load changes. Median APV concentration was 1750 ng/mL (IQR 1130, 2520). At month 4, using several cut‐offs, neither APV concentration nor the genotypic inhibitory quotient was predictive of viral load changes. Baseline viral load and the number of protease mutations were associated with outcome.

Conclusions

Efficacious APV concentrations need to be determined for antiretroviral‐experienced patients. Baseline viral load and the number of mutations on the protease coding region (PRO) were associated with the virological outcome of APV/RTV‐based regimens.
Causes of death among patients with HIV in Singapore from 1985 to 2001: results from the Singapore HIV Observational Cohort Study (SHOCS)
Authors: Bellamy R , Sangeetha S , Paton NI
Published: July 2004

Objectives

To investigate the major primary and contributory causes of death among HIV patients in Singapore.

Design

A retrospective observational cohort study of all adult patients seen at the national referral centre for HIV in Singapore between 1985 and 2001.

Methods

Data were extracted from the patients' records by 10 trained health care workers. AIDS‐defining conditions were established using predefined criteria. For each case, a single principal cause of death and up to three contributory causes were identified.

Results

A total of 1504 patients aged 17 years or over were seen before the end of 2001, of whom 504 have died. The most frequent principal causes of death were Mycobacterium avium (17.5%), Mycobacterium tuberculosis (9.7%), pneumonia (cause unknown) (6.5%) and Cryptococcus neoformans (6.7%). Three hundred and eighteen patients (63.1%) died from an AIDS‐defining condition.

Conclusions

The causes of death were similar to those found in Western cohorts, except that disseminated M. avium was a more frequent cause of death.