bluuebunny/crossref_metadata_2025 huggingface dataset:
High sound absorption of porous aluminum fabricated by spacer method
Authors: Hakamada Masataka , Kuromura Tetsunume , Chen Youqing , Kusuda Hiromu , Mabuchi Mamoru
Published: June 2006

Porous aluminum with a density of 0.27g∕cm3 was produced by the spacer method. The sound absorbency of the material is significantly improved by inserting an air gap between the sample and the rigid back surface; in this manner, a sound absorption coefficient near unity can be achieved over a significant portion of the audible range. The present data agree with the theoretical analysis in the previous study by Lu et al. [J. Acoust. Soc. Am. 108, 1697 (2000)]; this in turn shows that the present results can largely be attributed to the size (= approximately 50μm) of apertures connecting pores in the material.
New methods to improve symbiotic propagation of temperate terrestrial orchid seedlings from axenic culture to soil
Authors: Batty A. L. , Brundrett M. C. , Dixon K. W. , Sivasithamparam K.
Published: June 2006

This research aimed to improve the success of soil transfer of terrestrial orchid seedlings after symbiotic germination in the laboratory. Three native Western Australian terrestrial orchids (Caladenia arenicola Hopper & A.P.Brown, Diuris magnifica D.L.Jones and Thelymitra crinita Lindley) were used in this study. The key to improved seedling survival on transfer to soil was found to be the use of an intermediate stage between the Petri dish and soil where larger seedlings were grown in an axenic environment with controlled humidity. There was no apparent benefit of pre-inoculating potting medium with appropriate strains of mycorrhizal fungi for subsequent growth of symbiotic seedlings under glasshouse conditions. Initial survival of seedlings in the glasshouse was high. However, some seedlings failed to produce tubers (from modified roots or droppers) necessary for plant survival through the summer dormancy period, and this caused survival to decrease to 40–60% of the glasshouse-grown seedlings in the first year. The initiation of tubers on droppers by C. arenicola was inversely correlated with leaf size, with smaller plants more likely to form tubers. This suggests that leaves and tubers were competing for resources. However, larger seedlings that did tuberise had larger tubers that were more likely to survive summer dormancy. There was no correlation between leaf size and root tuber size in D. magnifica, but the number of tubers produced was greatest in larger plants. As with C. arenicola, plants of D. magnifica and T. crinita with larger tubers were more likely to survive summer dormancy. Methods developed in this study enable the production of both actively growing symbiotic seedlings and dormant tubers which improve the success of translocation of laboratory-grown terrestrial orchids to field sites.
Survival of transplanted terrestrial orchid seedlings in urban bushland habitats with high or low weed cover
Authors: Scade A. , Brundrett M. C. , Batty A. L. , Dixon K. W. , Sivasithamparam K.
Published: June 2006

The conservation of wild orchid populations may depend on the establishment of propagated orchids to field sites to help sustain depleted populations if natural recruitment is not successful. However, very little is known about biotic factors which influence the establishment of terrestrial orchid seedlings in natural habitats. An experiment was established to measure the survival of six orchid species during their first growing season following transplantation to a West Australian urban bushland with a Banksia and Eucalyptus canopy and understorey dominated either by weeds or native vegetation. Symbiotically germinated orchid seedlings raised in the laboratory for 5 months before planting were established in adjacent field sites with high or low weed cover. There was a gradual mortality of seedlings at field sites throughout the growing season, primarily owing to insect grazing, and this was not affected by the enclosure of seedlings by wire mesh or shade cloth. Overall rates of survival varied from 49% for Microtis media R.Br., a species capable of growing in disturbed habitats, to 21% for Caladenia arenicola Hopper & A.P.Brown, the most common native orchid at these sites. However, not all surviving seedlings produced a tuber, so their expected rate of survival after the next dry season was reduced further. The factors having the greatest impact on seedling survival were site aspect (slope and canopy cover), weed cover and orchid species respectively. Orchid seedling survival was not well correlated with the presence of existing orchids of the same species at the same sites or the presence of compatible fungi in soil at these sites (simultaneously measured by orchid seed baiting).
Temperature and dormancy-breaking treatments: germination of endemic and geographically restricted herbaceous perennials
Authors: Cochrane Anne , Probert Robin
Published: June 2006

This paper describes the effects of temperature and simple or multiple dormancy-breaking treatments (potassium nitrate, surgical treatment, gibberellic acid (GA3), after-ripening at 45°C and nitrogen dioxide gas) on germination of five endemic and geographically restricted herbaceous perennials (Apium prostratum Vent. subsp. phillipii Keighery ms, Goodenia stenophylla F.Muell., Marianthus granulatus (Turcz.) Benth, Myriocephalus suffruticosus Benth. and Velleia foliosa (Benth.) K.Krause) from the species-rich south-west of Western Australia. Except for seeds of A. prostratum that were non-dormant, seeds were partially dormant or fully dormant when incubated without pre-treatment at three temperatures (15, 20 and 25/10°C). Low germination (≤52%) was detected in M. granulatus under the best identified conditions, and seeds of G. stenophylla showed little to no response to any germination cue. In M. granulatus, M. suffruticosus and V. foliosa combinations of treatments were found that led to enhanced germination and in the case of V. foliosa, germination was not significantly different from a tetrazolium test of viability when seeds were surgically treated and then incubated with KNO3. Although none of the species studied exhibited physical dormancy, surgical excision of the seed coat in the vicinity of the embryo featured in the most successful combination of treatments in every case. Whilst seeds of M. granulatus responded positively to surgical treatment, after-ripening of seeds at 45°C for 2, 4 or 6 weeks did not increase either speed or final germination compared with other treatments. The mean time to germinate (MTG) ranged from 12.6 days (A. prostratum ssp. phillipii) to 46.5 days (G. stenophylla) under the best treatment conditions for each species.
Chromosome studies in species of Eugenia, Myrciaria and Plinia (Myrtaceae) from south-eastern Brazil
Authors: Ribeiro da Costa Itayguara , Forni-Martins Eliana Regina
Published: June 2006

The chromosome numbers of Brazilian species of Myrtaceae were reassessed in the context of chromosomal evolution in fleshy-fruited Myrteae. The chromosome numbers of 14 species of Eugenia, three of Myrciaria and two of Plinia were determined, 14 of which had not been published before. In Eugenia, a diploid state (2n = 22) was found in nine species, polyploid (2n = 33 or 2n = 44) in three species, and both diploid and polyploid cytotypes in another three species. The percentage of Eugenia species with a known chromosome number increased from 19 to 31 species, 22.6% of which were polyploid (3 triploid, 1 tetraploid and 3 hexaploid) and a further 16.1% either dysploid from the triploid level or had both diploid and polyploid races, giving a total of 38.7% in which polyploidy is recorded. In Myrciaria (3 species) and Plinia (2 species), the chromosome number was 2n = 22, with no polyploidy known in these genera. The results reinforce the previous indications that polyploidy is of great importance in the evolution of fleshy-fruited Myrteae.
A classification and census of regenerative strategies in the eucalypts (Angophora, Corymbia and Eucalyptus—Myrtaceae), with special reference to the obligate seeders
Authors: Nicolle Dean
Published: June 2006

A survey of regenerative strategies in the eucalypts, including lignotuber development, was undertaken by extensive field observations, seedling trials and trials of cultivated individuals over a 12-year period. Four broad regenerative strategies were identified, viz. obligate seeders, lignotuber sprouters, stem sprouters and combination sprouters. These four regenerative strategies are based on the ability to develop a lignotuber and the regeneration strategy after whole-crown destruction. These regenerative strategies do not wholly correspond to the tree, mallee, mallet, marlock and shrub habit categories commonly applied to eucalypts. The obligate seeders include many more terminal taxa than have been previously documented as mallet taxa, with 78 western obligate seeders (the ‘true’ mallets) and nine eastern obligate seeders listed herein. Obligate seeders do not possess a lignotuber and are killed by crown-destructive events, and as such are relatively short-lived in most natural environments. A further 16 taxa are also known to be non-lignotuberous, but these are capable of producing epicormic regrowth from the trunk following crown destruction and are defined as stem sprouters. The remaining two regenerative strategies include taxa that are both lignotuberous and able to regenerate vegetatively following disturbance events. The persistent and conjecturous mallet–marlock–moort distinction is rejected, this study showing it to be dependent on stand density. Data presented indicate no significant difference in germination time or maturation time between western obligate-seeder taxa and closely related sprouter taxa. The conservation status of obligate-seeder taxa is discussed. Nomenclatural issues regarding the taxonomic distinction between obligate-seeder and resprouter sister taxa are discussed. A census of regenerative strategies for all recognised eucalypt taxa is included as an accessory publication on the web.
Small-scale patterns of abundance of mosses and lichens forming biological soil crusts in two semi-arid gypsum environments
Authors: Martínez I. , Escudero A. , Maestre F. T. , de la Cruz A. , Guerrero C. , Rubio A.
Published: June 2006

Despite important advances in the understanding of biological soil crusts and their key role in ecosystem processes in arid and semi-arid environments, little is known about those factors driving the small-scale patterns of abundance and distribution of crust-forming lichens and mosses. We used constrained ordination techniques (RDAs) to test the hypothesis that the spatial patterning of lichens and mosses is related to surface and subsurface soil variables in two semi-arid gypsum environments of Spain. Our results show that the abundance of mosses and lichens forming biological soil crusts was related to a limited set of variables (cover of bare soil and litter, soil respiration, potassium content and aggregate stability). Moreover, they provide some insights into the importance of these variables as drivers of biological soil-crust composition and abundance in semi-arid gypsum environments.
Myxomycetes on the bark of Banksia attenuata and B. menziesii (Proteaceae)
Authors: Jordan C. C. , Brims M. H. , Speijers E. J. , Davison E. M.
Published: June 2006

Myxomycetes on the bark of dead Banksia attenuata and B. menziesii from the Perth metropolitan area of Western Australia were surveyed by the moist chamber technique, to determine whether the flora was similar on both hosts and what were the most important variables that determined the distribution of the most common species. Twenty-seven species of myxomycetes were recovered, including six new records for Australia (Comatricha rigidireta, Echinostelium elachiston, Paradiacheopsis cf. cribrata, P. rigida, Stemonitopsis amoena and S. cf. hyperopta). Members of the order Stemonitales comprised the largest number of species, whereas members of the Liceales occurred on the most bark pieces. The most common species were Licea kleistobolus, Echinostelium minutum, Comatricha elegans, Cribraria minutissima and Paradiacheopsis fimbriata. Overall, B. menziesii and B. attenuata had very similar myxomycete productivity, diversity and species assemblage, as did the tops and bottoms of the logs. It was concluded that they provided very similar microhabitats for myxomycetes. Both pH and the relative moisture content of the bark had an effect on myxomycete productivity. Bark decomposition level, pH and bark surface (top or bottom) were the most important variables determining the distribution of the most common myxomycete species.
Changing Australian vegetation from 1788 to 1988: effects of CO2 and land-use change
Authors: Berry Sandra L. , Roderick Michael L.
Published: June 2006

We present a tractable and transparent approach (the TMSC model) to estimating the total stock of carbon (roots, stems and leaves) in living vegetation (C
living), from gross primary productivity (GPP) estimates. The TMSC model utilises the TMS scheme of canopy functional types and a generic allometric scheme to derive these estimates. Model estimates are presented for the Australian continent under the following three vegetation–[CO2] scenarios: the present (1988) vegetation and a hypothetical natural (1988) vegetation cover with atmospheric CO2 concentration ([CO2]) of 350 µmol mol–1 (pveg350 and nveg350), and the natural vegetation (1788) having [CO2] of 280 µmol mol–1 (nveg280). The change between the nveg280 and pveg350 scenarios represents the combined effects of changes in land use and CO2. The change resulting from CO2 alone is the difference between the nveg280 and nveg350 scenarios. The estimated C
living for the continent is 21 Gt for pveg350, 23 Gt for nveg350 and 10 Gt for nveg280. This translates to an averaged rate of increase in C
living (CSI) of about 50 Tg C year–1 over the last 200 years for the continent. Where wooded areas have been extensively cleared for agriculture, the CSI is negative (down to –4 g C m–2 year–1). Elsewhere, the CSI over the last 200 years ranges from ~55 g C m–2 year–1 in the tropical and subtropical forests to ~0 g C m–2 year–1 in the most arid regions.
Establishing long-term colonies of marsupials to provide models for studying developmental mechanisms and their application to fertility control
Authors: Selwood Lynne , Cui Shuliang
Published: June 2006

To study marsupial developmental mechanisms and their application to fertility control, it is necessary to develop reliable procedures for breeding, colony maintenance, reproductive monitoring for obtaining known-age embryos and, if possible, an induced ovulation protocol. These procedures also provide means to enhance conservation of endangered species. Such procedures are examined in the stripe-faced dunnart, an excellent model for developmental analysis, and the common brush-tail possum, an agricultural and ecological pest species in New Zealand that has become a model for fertility control in marsupials. A long-term colony of the stripe-faced dunnart has been in existence for 21 years, and the procedures for its maintenance and continued survival are outlined, and include minimal reproductive contributions from wild-caught animals, and development of an appropriate timetable of development and induced-ovulation protocols. Common brushtail possum colonies are relatively frequent but have regular input from wild-caught animals. Procedures that minimise competition for prized resources and allow successful group housing of possums are outlined. For both species the available development timetables, in vitro techniques and induced ovulation protocols are essential tools for the study of developmental mechanisms and fertility control, respectively, and also have considerable implications for conservation of these and other species.
Sexual development of a model marsupial male
Authors: Renfree Marilyn B. , Pask Andrew J. , Shaw Geoff
Published: June 2006

In eutherian mammals sexual differentiation occurs during fetal development, making experimental manipulation difficult, unlike in marsupials. We are investigating the roles of several key genes and hormones whose exact role in gonadal differentiation is still unclear using the tammar wallaby (Macropus eugenii) as a model. As in humans, unlike in mice, the testis-determining gene SRY is expressed in male tammar fetuses in many tissues over an extended period. Not all sexual differentiation depends on testicular hormones. Scrotum and mammary glands are under the control of X-linked gene(s). Our demonstration of DMRT1 expression in tammar and mouse ovaries suggests it has a wider role than previously thought. The Y-borne copy of ATRX (ATRY) is coexpressed with DMRT1 in developing testis. Gonadal sex reversal can be induced in males by neonatal oestrogen treatment and in females by grafting developing ovaries to males or culturing them in minimal medium. Treatments of developing young with various androgens, and studies of steroid metabolism have shown that the steroid androstenediol may have a previously unrecognised role in virilisation. Our studies using a marsupial model have given some surprising insights into the evolution and control of sexual development in all mammals.
Evolution of sexual segregation in mammalian herbivores: kangaroos as marsupial models
Authors: Coulson G. , MacFarlane A. M. , Parsons S. E. , Cutter J.
Published: June 2006

Sexual segregation is best known in sexually dimorphic ungulates. Many hypotheses have been proposed to explain the evolution of sexual segregation in ungulates, but all are reducible to the influence of two factors: body size and sex-specific reproductive strategy. Definitive tests of these hypotheses are lacking in ungulates because these factors are confounded, all males being somewhat larger than females. Kangaroos represent a parallel radiation of terrestrial herbivores, but their populations are composed of a spectrum of adult body sizes, ranging from small males the same size as females to large males more than twice the size. We exploited this heteromorphism to assess the independent influences of size and sex in these ungulate analogues. We conducted a preliminary study of western grey kangaroos (Macropus fuliginosus) in north-western Victoria, Australia. Adult males predominately occupied grassland habitat, whereas females occurred mostly in lakebed, woodland and shrubland. Single-sex groups occurred more often than expected during the non-mating season. The diet of large males had the highest proportion of grass, and females had the least. These initial results indicate that both size and sex influence segregation in this species, confirming the worth of kangaroos as marsupial models for research into the evolution of sexual segregation.
Dasyurid marsupials as models for the physiology of ageing in humans
Authors: McAllan B. M.
Published: June 2006

Marsupials of the order Dasyuromorphia have features that make them useful as models for ageing processes in humans. First, they are long-lived for their size, with most small species living for at least 1 year, often several years, contrasting with the mouse, a conventional model for ageing studies, where most populations turn over within 4–6 months. Longevity in some dasyurids allows biological comparisons with other long-lived mammals. Second, the predictable reproduction and life histories of the genera Antechinus and Sminthopsis allow analysis of the role of sex hormones in physiological changes as ageing progresses. For Antechinus, this includes the interaction between testosterone and cortisol in initiating pathologies in males but not females. Many ageing processes are expressed differently between male and female humans, and have a stress component. The neuropathological changes that occur in Antechinus can be used as a model for the dementias of ageing, including Alzheimer’s disease. The age-related neuropathologies in Antechinus indicate that hormonal influences may be important. Finally, in Sminthopsis, the interaction between sex hormones, reproduction and the fattening season offer insights into the interaction between longevity and reduced energy intake, including obesity. Thus these mammals offer useful models for many of the possible influences for healthy ageing in humans.
Sirtuins deacetylate and activate mammalian acetyl-CoA synthetases
Authors: Hallows William C. , Lee Susan , Denu John M.
Published: June 2006

Silent Information Regulator 2 (Sir2) enzymes (or sirtuins) are NAD
+
-dependent deacetylases that modulate gene silencing, aging and energy metabolism. Previous work has implicated several transcription factors as sirtuin targets. Here, we investigated whether mammalian sirtuins could directly control the activity of metabolic enzymes. We demonstrate that mammalian Acetyl-CoA synthetases (AceCSs) are regulated by reversible acetylation and that sirtuins activate AceCSs by deacetylation. Site-specific acetylation of mouse AceCS1 on Lys-661 was identified by using mass spectrometry and a specific anti-acetyl-AceCS antibody. SIRT1 was the only member of seven human Sir2 homologues capable of deacetylating AceCS1 in cellular coexpression experiments. SIRT1 expression also led to a pronounced increase in AceCS1-dependent fatty-acid synthesis from acetate. Using purified enzymes, only SIRT1 and SIRT3 exhibited high catalytic efficiency against acetylated AceCS1. In mammals, two AceCSs have been identified: cytoplasmic AceCS1 and mitochondrial AceCS2. Because SIRT3 is localized to the mitochondria, we investigated whether AceCS2 also might be regulated by acetylation, and specifically deacetylated by mitochondrial SIRT3. AceCS2 was completely inactivated upon acetylation and was rapidly reactivated by SIRT3 deacetylation. Lys-635 of mouse AceCS2 was identified as the targeted residue. Using reversible acetylation to modulate enzyme activity, we propose a model for the control of AceCS1 by SIRT1 and of AceCS2 by SIRT3.
Dietary intake of different types and characteristics of processed meat which might be associated with cancer risk – results from the 24-hour diet recalls in the European Prospective Investigation into Cancer and Nutrition (EPIC)
Authors: Linseisen Jakob , Rohrmann Sabine , Norat Teresa , Gonzalez Carlos A , Iraeta Miren Dorronsoro , Gómez Patrocinio Morote , Chirlaque Maria-Dolores , Pozo Basilio G , Ardanaz Eva , Mattisson Irene , Pettersson Ulrika , Palmqvist Richard , Guelpen Bethany Van , Bingham Sheila A , McTaggart Alison , Spencer Elizabeth A , Overvad Kim , Tjønneland Anne , Stripp Connie , Clavel-Chapelon Françoise , Kesse Emmanuelle , Boeing Heiner , Klipstein-Grobusch Kerstin , Trichopoulou Antonia , Vasilopoulou Effie , Bellos George , Pala Valeria , Masala Giovanna , Tumino Rosario , Sacerdote Carlotta , Del Pezzo Mariarosaria , Bueno-de-Mesquita H Bas , Ocke Marga C , Peeters Petra HM , Engeset Dagrun , Skeie Guri , Slimani Nadia , Riboli Elio
Published: June 2006

Objective

There is increasing evidence for a significant effect of processed meat (PM) intake on cancer risk. However, refined knowledge on how components of this heterogeneous food group are associated with cancer risk is still missing. Here, actual data on the intake of PM subcategories is given; within a food-based approach we considered preservation methods, cooking methods and nutrient content for stratification, in order to address most of the aetiologically relevant hypotheses.

Design and setting

Standardised computerised 24-hour diet recall interviews were collected within the framework of the European Prospective Investigation into Cancer and Nutrition (EPIC), a prospective cohort study in 27 centres across 10 European countries.

Subjects

Subjects were 22 924 women and 13 031 men aged 35–74 years.

Results

Except for the so-called ‘health-conscious’ cohort in the UK, energy-adjusted total PM intake ranged between 11.1 and 47.9 g day−1 in women and 18.8 and 88.5 g day−1 in men. Ham, salami-type sausages and heated sausages contributed most to the overall PM intake. The intake of cured (addition of nitrate/nitrite) PM was highest in the German, Dutch and northern European EPIC centres, with up to 68.8 g day−1 in men. The same was true for smoked PM (up to 51.8 g day−1). However, due to the different manufacturing practice, the highest average intake of NaNO2 through PM consumption was found for the Spanish centres (5.4 mg day−1 in men) as compared with German and British centres. Spanish centres also showed the highest intake of NaCl-rich types of PM; most cholesterol- and iron-rich PM was consumed in central and northern European centres. Possibly hazardous cooking methods were more often used for PM preparation in central and northern European centres.

Conclusions

We applied a food-based categorisation of PM that addresses aetiologically relevant mechanisms for cancer development and found distinct differences in dietary intake of these categories of PM across European cohorts. This predisposes EPIC to further investigate the role of PM in cancer aetiology.
Accuracy of estimates of food portion size using food photographs – the importance of using age-appropriate tools
Authors: Foster Emma , Matthews John NS , Nelson Michael , Harris Julie M , Mathers John C , Adamson Ashley J
Published: June 2006

Background

In order to obtain a measure of nutrient intake, a measure or estimate of the amount of food consumed is required. Weighing foods imposes a large burden on subjects, often resulting in underreporting. Tools are available to assist subjects in providing an estimate of portion size and these include food photographs. The application of these tools in improving portion size estimation by children has not been investigated systematically.

Objectives

To assess the accuracy with which children are able to estimate food portion sizes using food photographs designed for use with adults, and to determine whether the accuracy of estimates is improved when age-appropriate portion size photographs are provided.

Design

Original data from three separate studies, on the accuracy of portion size estimates by adults using food photographs, by children using adult photographs and by children using age-appropriate photographs, are analysed and compared.

Subjects

One hundred and thirty-five adults aged 18 to 90 years and 210 children aged 4 to 11 years.

Results

Children's estimates of portion sizes using age-appropriate food photographs were significantly more accurate (an underestimate of 1% on average) than estimates using photographs designed for use with adults (an overestimate of 45% on average). Accuracy of children's estimates of portion size using age-appropriate photographs was not significantly different from that of adults. Children overestimated a food's weight by 18% on average and adults underestimated by 5%.

Conclusions

Providing children with food photographs depicting age-appropriate portion sizes greatly increases the accuracy of portion size estimates compared with estimates using photographs designed for use with adults.
National Diet and Nutrition Surveys: the British experience
Authors: Ashwell Margaret , Barlow Susan , Gibson Sigrid , Harris Caroline
Published: June 2006

Objective

The National Diet and Nutrition Surveys (NDNS) are a series of government-funded surveys of food intake, nutrient intake and nutritional status of individuals, undertaken to support nutritional policy and risk assessment. This paper summarises a review that considered the extent to which NDNS met the needs of users and suggested options for the future. The Food Standards Agency has since progressed favoured options. This paper aims to help others wishing to obtain this type of information within their own populations.

Design

A detailed questionnaire was used to probe use of data and gather opinions from users, producers and managers of the NDNS. It asked about general information needs from NDNS and changes that might be made. This was followed by a two-day workshop which included discussion of the main issues and the generation of 19 possible future options for consideration by the Agency.

Results

Options to improve effectiveness included methods to prioritise breadth and depth of coverage and possible ways of improving response and compliance. Strategies to make surveys more efficient and timely, such as adopting a rolling programme, disaggregating survey components, integrating with other studies and improving data access, were also suggested. A rolling programme, in which data are collected continuously, was the favoured option to address some of the concerns and a strategy is now in place to achieve this.

Conclusions

There is widespread support for the NDNS from its users. There is no alternative source for such high-quality data on food and nutrient consumption and nutritional status and physical measurements in the same individuals. Useful information, such as the potential value of using a rolling programme from the outset, can be gained from this British experience by others wishing to measure food and nutrient intakes and status in their own populations.
Children of Chernobyl
Authors: Klaščuk Anatol
Published: June 2006

NOW TWENTY YEARS OLD, CHILDREN BORN ON THE DAY OF THE EXPLOSION BUILD THEIR FUTURE
Identities and the Subversion of Borders
Authors: Eshun Ekow
Published: June 2006

THE SEARCH FOR HOME BEGINS WHERE WE HAVE ARRIVED. BY LAYING CLAIM TO A PLACE WE FIND OUR IDENTITY AND BEGIN TO CHANGE THAT OF THE WORLD AROUND US
Chernobyl: the Big Lie
Authors: Yaroshinskaia Alla
Published: June 2006

IT HAS TAKEN 20 YEARS FOR THE TRUTH OF THE CHERNOBYL DISASTER TO COME TO LIGHT, AND EVEN NOW THE FULL EXTENT OF THE CONSEQUENCES REMAINS UNCERTAIN
Rites, Rituals and Cemeteries
Authors: Ramaniuk Dzianis
Published: June 2006

ANCIENT RITUALS, PAGAN AND CHRISTIAN, BRING THE OLD FOLK BACK TO THE CONTAMINATED LAND OF BELARUS
Sacrificial Therapy
Authors: Dynko Andrej
Published: June 2006

Andrej Dynko, editor of Nasha Niva, one of the last remaining independent newspapers in Belarus, was arrested on 21 March, two days after the Belarusan election, while attempting to bring food to demonstrators camped in October Square in Minsk. They were protesting the election victory of incumbent president Alaksandr Lukashenko. Along with many others taking part in the protests, Dynko was sentenced to ten days in prison for ‘hooliganism’. On the night of 27/28 March, he wrote his ‘Letter from a prison in Minsk’ from which we print the following excerpts
Parallel Lives
Authors: Cantle Ted
Published: June 2006

WE MAY LIVE IN A MULTICULTURAL SOCIETY, BUT WE NEED A MORE POSITIVE APPROACH TO BREAKING DOWN SEGREGATION
Summation in Causal Learning: Elemental processing or Configural Generalization?
Authors: Collins Darrell J. , Shanks David R.
Published: June 2006

Results from human causal learning tasks that employ multiple cues are often interpreted in terms of the elemental theory of Rescorla and Wagner (1972). However, most results can also be successfully interpreted by the configural model proposed by Pearce (1987, 1994). One method of discriminating between these alternatives is through an investigation of summation and overexpectation. Indeed, demonstrations of these phenomena are fundamental to an elemental approach but are generally incompatible with an account that involves configural processing. Using a procedure in which the magnitude of the outcome varied, evidence for both summation and overexpectation was obtained in two experiments.
Involvement of Syntaxin 18, an Endoplasmic Reticulum (ER)-localized SNARE Protein, in ER-mediated Phagocytosis
Authors: Hatsuzawa Kiyotaka , Tamura Taku , Hashimoto Hitoshi , Hashimoto Hiromi , Yokoya Sachihiko , Miura Megumi , Nagaya Hisao , Wada Ikuo
Published: June 2006

The endoplasmic reticulum (ER) is thought to play an important structural and functional role in phagocytosis. According to this model, direct membrane fusion between the ER and the plasma or phagosomal membrane must precede further invagination, but the exact mechanisms remain elusive. Here, we investigated whether various ER-localized SNARE proteins are involved in this fusion process. When phagosomes were isolated from murine J774 macrophages, we found that ER-localized SNARE proteins (syntaxin 18, D12, and Sec22b) were significantly enriched in the phagosomes. Fluorescence and immuno-EM analyses confirmed the localization of syntaxin 18 in the phagosomal membranes of J774 cells stably expressing this protein tagged to a GFP variant. To examine whether these SNARE proteins are required for phagocytosis, we generated 293T cells stably expressing the Fcγ receptor, in which phagocytosis occurs in an IgG-mediated manner. Expression in these cells of dominant-negative mutants of syntaxin 18 or D12 lacking the transmembrane domain, but not a Sec22b mutant, impaired phagocytosis. Syntaxin 18 small interfering RNA (siRNA) selectively decreased the efficiency of phagocytosis, and the rate of phagocytosis was markedly enhanced by stable overexpression of syntaxin 18 in J774 cells. Therefore, we conclude that syntaxin 18 is involved in ER-mediated phagocytosis, presumably by regulating the specific and direct fusion of the ER and plasma or phagosomal membranes.
Nonredundant Roles of Mitochondria-associated F-Box Proteins Mfb1 and Mdm30 in Maintenance of Mitochondrial Morphology in Yeast
Authors: Dürr Mark , Escobar-Henriques Mafalda , Merz Sandra , Geimer Stefan , Langer Thomas , Westermann Benedikt
Published: June 2006

Mitochondria constantly fuse and divide to adapt organellar morphology to the cell’s ever-changing physiological conditions. Little is known about the molecular mechanisms regulating mitochondrial dynamics. F-box proteins are subunits of both Skp1-Cullin-F-box (SCF) ubiquitin ligases and non-SCF complexes that regulate a large number of cellular processes. Here, we analyzed the roles of two yeast F-box proteins, Mfb1 and Mdm30, in mitochondrial dynamics. Mfb1 is a novel mitochondria-associated F-box protein. Mitochondria in mutants lacking Mfb1 are fusion competent, but they form aberrant aggregates of interconnected tubules. In contrast, mitochondria in mutants lacking Mdm30 are highly fragmented due to a defect in mitochondrial fusion. Fragmented mitochondria are docked but nonfused in Δmdm30 cells. Mitochondrial fusion is also blocked during sporulation of homozygous diploid mutants lacking Mdm30, leading to a mitochondrial inheritance defect in ascospores. Mfb1 and Mdm30 exert nonredundant functions and likely have different target proteins. Because defects in F-box protein mutants could not be mimicked by depletion of SCF complex and proteasome core subunits, additional yet unknown factors are likely involved in regulating mitochondrial dynamics. We propose that mitochondria-associated F-box proteins Mfb1 and Mdm30 are key components of a complex machinery that regulates mitochondrial dynamics throughout yeast’s entire life cycle.
Guanylyl Cyclase Protein and cGMP Product Independently Control Front and Back of ChemotaxingDictyosteliumCells
Authors: Veltman Douwe M. , Van Haastert Peter J.M.
Published: June 2006

Chemotaxis of amoeboid cells is driven by actin filaments in leading pseudopodia and actin–myosin filaments in the back and at the side of the cell to suppress pseudopodia. In Dictyostelium, cGMP plays an important role during chemotaxis and is produced predominantly by a soluble guanylyl cyclase (sGC). The sGC protein is enriched in extending pseudopodia at the leading edge of the cell during chemotaxis. We show here that the sGC protein and the cGMP product have different functions during chemotaxis, using two mutants that lose either catalytic activity (sGCΔcat) or localization to the leading edge (sGCΔN). Cells expressing sGCΔN exhibit excellent cGMP formation and myosin localization in the back of the cell, but they exhibit poor orientation at the leading edge. Cells expressing the catalytically dead sGCΔcat mutant show poor myosin localization at the back, but excellent localization of the sGC protein at the leading edge, where it enhances the probability that a new pseudopod is made in proximity to previous pseudopodia, resulting in a decrease of the degree of turning. Thus cGMP suppresses pseudopod formation in the back of the cell, whereas the sGC protein refines pseudopod formation at the leading edge.
Distinct Roles for TGN/Endosome Epsin-like Adaptors Ent3p and Ent5p
Authors: Costaguta Giancarlo , Duncan Mara C. , Fernández G. Esteban , Huang Grace H. , Payne Gregory S.
Published: June 2006

Clathrin adaptors are key factors in clathrin-coated vesicle formation, coupling clathrin to cargo and/or the lipid bilayer. A physically interacting network of three classes of adaptors participate in clathrin-mediated traffic between the trans-Golgi network (TGN) and endosomes: AP-1, Gga proteins, and epsin-like proteins. Here we investigate functional relationships within this network through transport assays and protein localization analysis in living yeast cells. We observed that epsin-like protein Ent3p preferentially localized with Gga2p, whereas Ent5p distributed equally between AP-1 and Gga2p. Ent3p was mislocalized in Gga-deficient but not in AP-1–deficient cells. In contrast, Ent5p retained localization in cells lacking either or both AP-1 and Gga proteins. The Ent proteins were dispensable for AP-1 or Gga localization. Synthetic genetic growth and α-factor maturation defects were observed when ent5Δ but not ent3Δ was introduced together with deletions of the GGA genes. In AP-1–deficient cells, ent3Δ and to a lesser extent ent5Δ caused minor α-factor maturation defects, but together resulted in a near-lethal phenotype. Deletions of ENT3 and ENT5 also displayed synthetic defects similar to, but less severe than, synthetic effects of AP-1 and Gga inactivation. These results differentiate Ent3p and Ent5p function in vivo, suggesting that Ent3p acts primarily with Gga proteins, whereas Ent5p acts with both AP-1 and Gga proteins but is more critical for AP-1–mediated transport. The data also support a model in which the Ent adaptors provide important accessory functions to AP-1 and Gga proteins in TGN/endosome traffic.
Physicians′ Attitudes Toward Complementary and Alternative Medicine and Their Knowledge of Specific Therapies: A Survey at an Academic Medical Center
Authors: Wahner-Roedler Dietlind L. , Vincent Ann , Elkin Peter L. , Loehrer Laura L. , Cha Stephen S. , Bauer Brent A.
Published: June 2006

The purpose of this study was to evaluate the attitudes of physicians at an academic medical center toward complementary and alternative medicine (CAM) therapies and the physicians′ knowledge base regarding common CAM therapies. A link to a Web‐based survey was e‐mailed to 660 internists at Mayo Clinic in Rochester, MN, USA. Physicians were asked about their attitudes toward CAM in general and their knowledge regarding specific CAM therapies. The level of evidence a physician would require before incorporating such therapies into clinical care was also assessed. Of the 233 physicians responding to the survey, 76% had never referred a patient to a CAM practitioner. However, 44% stated that they would refer a patient if a CAM practitioner were available at their institution. Fifty‐seven percent of physicians thought that incorporating CAM therapies would have a positive effect on patient satisfaction, and 48% believed that offering CAM would attract more patients. Most physicians agreed that some CAM therapies hold promise for the treatment of symptoms or diseases, but most of them were not comfortable in counseling their patients about most CAM treatments. Prospective, randomized controlled trials were considered the level of evidence required for most physicians to consider incorporating a CAM therapy into their practice. The results of this survey provide insight into the attitudes of physicians toward CAM at an academic medical center. This study highlights the need for educational interventions and the importance of providing physicians ready access to evidence‐based information regarding CAM.
Clinical economics review: gastrointestinal disease in primary care.
Authors: Jones RH
Published: June 2006

Gastrointestinal disorders are common in the general population, with annual prevalence figures ranging from 20% for irritable bowel syndrome to over 40% for dyspepsia. Less than one‐third of patients consult general practitioners for these problems, and anxiety about serious disease and cancer are as important in the decision to consult as symptom severity. Gastrointestinal disorders have significant socioeconomic effects in the community, and account for 10% of the work of general practitioners in the UK. The health economics implications of management in primary care relate principally to the costs of investigation and therapy, notably antisecretory drugs, endoscopy, radiology and specialist referral. Although guidelines based on evidence and agreed between primary and secondary care physicians offer an attractive approach to rationalizing the use of resources, there is at present little health service research evidence on which to base important decisions. For example, in dyspepsia, the role of Helicobacter pylori identification and eradication in an overall management strategy in primary care has yet to be defined. An exploration of the clinical economics of gastrointestinal disorders in general practice raises a number of research questions, which will require the attention of both generalists and specialists.
Low‐dose omeprazole plus clarithromycin and either tinidazole or amoxycillin for Helicobacter pylori infection.
Authors: Tursi A , Cammarota G , Montalto M , Papa A , Veneto G , Cuoco L , Trua F , Branca G , Fedeli G , Gasbarrini G
Published: June 2006

BACKGROUND: The aim of our study was to compare two 1‐week, low‐dose triple therapies for Helicobacter pylori eradication. METHODS: One hundred consecutive patients, suffering from dyspeptic symptoms with H. pylori infection, were randomly allocated to 7 days of treatment with omeprazole 20 mg o.m. plus clarithromycin 250 mg b.d. and either tinidazole 500 mg b.d. (group A: n = 50, 19 with peptic ulcer) or amoxycillin 1000 mg b.d. (group B: n = 50, 20 with peptic ulcer). H. pylori‐status was evaluated by means of histology, culture and urease test, at entry and 8 weeks after treatment. RESULTS: Three patients did not complete the treatment. H. pylori eradication was obtained in 35 patients from group A (73%) (95% CI, 55‐82%) and in 40 patients from group B (82%) (95% CI, 66‐90%). On intention‐to‐treat analysis, the rates of eradication were similar. Side‐effects occurred in seven patients from group A (14.58%) and in four patients from group B (8.33%), but none discontinued therapy because of side‐effects. CONCLUSION: Both triple 1‐week, low‐dose omeprazole therapies gave good eradication rates with infrequent side‐effects.
Picotamide inhibition of excess in vitro thromboxane B2 release by colorectal mucosa in inflammatory bowel disease.
Authors: Collins CE , Benson MJ , Burnham WR , Rampton DS
Published: June 2006

BACKGROUND: Inflammatory bowel disease is associated with increased mucosal release of eicosanoids. Among these, thromboxane A2 has been proposed as a possible inflammatory mediator; its suppression may be a useful therapeutic option. METHODS: Using a tissue incubation technique, we compared release of immunoreactive thromboxane B2 by colonic biopsies from patients with ulcerative colitis, Crohn's disease and controls, and assessed the inhibitory effect of picotamide, a thromboxane synthesis inhibitor‐receptor antagonist, which has been widely used in Italy for management of ischaemic heart and cerebrovascular disease. RESULTS: Increased amounts of thromboxane B2 were released from biopsies from patients with active ulcerative colitis (median 238 pg/20 min/mg wet weight (interquartile range 147‐ 325), n = 12) and active Crohn's disease (252 (174‐450), 6) compared with those from patients with quiescent ulcerative colitis (95 (61‐ 140), 12) or Crohn's disease (105 (57‐201), 13), or controls (136 (64‐ 206), 8). Incubation with picotamide at concentrations between 100 microM and 1 mM reduced thromboxane B2 release (IC50 890 microM). CONCLUSION: Since increased thromboxane A2 production may have pathogenetic importance, thromboxane synthesis inhibitor‐receptor antagonists such as picotamide merit therapeutic trial in the management of inflammatory bowel disease.
Strengths and limitations of the Crohn's disease activity index, revealed by an objective gut lavage test of gastrointestinal protein loss.
Authors: Acciuffi S , Ghosh S , Ferguson A
Published: June 2006

BACKGROUND: Several factors contribute to overall illness in patients with inflammatory bowel disease. The Crohn's disease activity index (CDAI), correlates closely with symptoms and is widely used to assess efficacy in clinical trials; previous work indicated that a gut lavage test for protein‐losing enteropathy (PLE) may measure the same symptomatic, acute inflammatory component of overall inflammatory bowel disease illness. METHODS: Results of the protein‐losing enteropathy test have been compared with the CDAI in 42 routinely presenting inflammatory bowel disease patients, and in 26 patients with ileostomies, eight children and five psychologically disturbed individuals with inflammatory bowel disease. RESULTS: For general adult patients with Crohn's disease or ulcerative colitis, concentrations of proteins in gut lavage fluid, particularly IgG, correlated well with CDAI. However, high CDAIs (> 150) were obtained in patients with fibrous small bowel strictures, in psychologically disturbed patients and also in five of seven patients in whom a provisional diagnosis of inflammatory bowel disease was subsequently shown to be wrong. In all these cases, normal values in the protein‐losing enteropathy test reinforced the clinical judgement of a low probability of acute inflammatory activity of the inflammatory bowel disease. In the children, results of the protein‐losing enteropathy test were positive in all cases; this was consistent with the clinical diagnosis, but CDAI values ranged from ‐66 to 275. In ileostomy patients, concentrations of IgG in gut lavage fluid discriminated well between groups judged, globally, to have either acute inflammatory activity or inactive disease, but there was no significant association with CDAI. CONCLUSIONS: These data confirm that, in most inflammatory bowel disease patients, the CDAI measures a true biological phenomenon which also causes gastrointestinal protein loss. However there are a number of situations where the CDAI in inappropriate or unreliable; for these, tests based on whole gut lavage, including the protein‐losing enteropathy test, offer an alternative method to measure the efficacy of pharmacological and other anti‐inflammatory therapies.
The effects of omeprazole 20 and 40 mg twice daily on intragastric acidity in duodenal ulcer patients.
Authors: Savarino V , Mela GS , Zentilin P , Mele MR , Vigneri S , Mansi C , Celle G
Published: June 2006

BACKGROUND: The combination of omeprazole with amoxycillin or clarithromycin is used as treatment against Helicobacter pylori. It seems likely that the antibacterial activity of the antibiotic may be improved by increasing gastric pH towards neutrality, and a twice daily regimen of omeprazole is probably needed. AIM: To assess the effects of twice daily administration of omeprazole 20 and 40 mg. METHODS: Twelve duodenal ulcer patients in remission were randomized to receive in single‐blind fashion either placebo, omeprazole 20 mg or omeprazole 40 mg twice daily (08.00 and 20.00 h). On the sixth day of dosing they underwent 24‐h gastric pH‐metry. RESULTS: Omeprazole 20 and 40 mg b.d. produced marked decreases (P < 0.001) of 24‐h gastric acidity (pH 5.4 +/‐ 0.9 and pH 5.7 +/‐ 0.6, respectively, vs. a basal pH of 1.4 +/‐ 0.2) and kept gastric pH at levels higher than 3.0 for almost 24 h. Gastric pH was kept above 5.0 for about 18 h and above 6.0 for about 10 h, while the time spent above 7.0 did not exceed 3 h. There were no significant differences between the two omeprazole dosages at any pH threshold. CONCLUSION: Omeprazole 20 mg b.d. is sufficient to render the gastric milieu as anacidic as possible in duodenal patients.