Why flies? Inexpensive public engagement exercises to explain the value of basic biomedical research on Drosophila melanogaster

Invertebrate model organisms are powerful systems for uncovering conserved principles of animal biology. Despite widespread use in scientific communities, invertebrate research is often severely undervalued by laypeople. Here, we present a set of simple, inexpensive public outreach exercises aimed at explaining to the public why basic research on one particular invertebrate, the insect Drosophila melanogaster, is valuable. First, we designed seven teaching modules that highlight cutting-edge research in Drosophila genetics, metabolism, physiology, and behavior. We then implemented these exercises in a public outreach event that included both children and adults. Quantitative evaluation of participant feedback suggests that these exercises 1) teach principles of animal biology, 2) help laypeople better understand why researchers study fruit flies, and 3) are effective over a wide range of age groups. Overall, this work provides a blueprint for how to use Drosophila as a vehicle for increasing public awareness and appreciation of basic research on genetically tractable insects in particular and invertebrates in general.     

Fourth meeting of the European Network of Research Tissue Banks – Future strategy to increase collaborations in the supply of human tissue for biomedical research

This report records the Fourth meeting of the European Network of Research Tissue Bank (Brussels, 18th March 2004) which was attended by Mel Read MEP. The existing membership of this informal group represents European Human Research Tissue Bankers, biomedical researchers seeking access to human tissue and allied groups including animal welfare representatives. This Fourth meeting provided a forum to update members on individual activity in this area. A particular focus of this meeting was to consider the status of this group and future affiliations to increase the profile and activity of this Network. This meeting addressed differences in legislative and ethical requirements governing the use of human tissue in biomedical research in the different countries represented. Future activity of the ENRTB, planned at this meeting, will target harmonisation of current differences which are currently barriers to increased access to human tissue for biomedical research. Through the harmonisation of procurement, processing and distribution of human tissue specimens the ENRTB will provide a mechanism to benefit human health through increased use of human tissue in pharmacotoxicological studies and the associated replacement of animal tests.     

Phytoplankton growth and krill grazing during spring in the Bransfield Strait,Antarctica — Implications from sediment trap collections

Summary Phytoplankton primary production, biomass, species composition and sedimentation of organic matter (using a moored and a free drifting sediment trap) were measured in eastern Bransfield Strait during spring 1983. Biomass and primary production increased from low levels in late November (1 mgChla m^-3 and 400 mgC m^-2 d^-1) to bloom levels by the end of December (5 mgChla m^-3 and 1000 mgC m^-2 d^-1). The moored trap was deployed at 323 m depth for 22.5 days, and collected 2968 mgC and 67.6 mg chlorophyll a and derivatives per m² (132 and 3.0 mg m^-2 d^-1), of which 90% was in the form of krill faeces. These figures are regarded as egestion of krill, and using ingestion: egestion ratios from the literature, grazing loss of phytoplankton by krill was estimated at 45% of the primary production during a period of 3 weeks. Large-scale surveys of phytoplankton standing stock indicate that the build-up of blooms during spring is apparently not controlled by krill grazing. It is therefore suggested that the intense grazing that must have occurred over the trap during the period of deployment was only of local importance.     

Morphogenesis from cultured leaf tissue ofSorghum bicolor—The morphogenetic pathways

Summary Immature leaf explants ofSorghum bicolor (L.) Moench can be stimulatedin vitro to form roots, shoots or embryos. When the cultures were maintained with the high 2,4-D level which was essential for optimal culture initiation, the organs or embryos proliferated as suppressed primordia, but they could always be identified by simple histological means. Perivascular cells of comparatively old but still immature leaf sheath regions appeared to be strongly determined to form adventitious roots or root-type callus cultures. We have evidence that the embryogenic tissue, and ultimately the embryos, are of multicellular origin. This ontogeny of the embryos appears to be contradictory to the often stated view that somatic embryos generally arise from single committed cells. The implications of these findings for basic and applied research on cereal tissue culture are discussed.Abbreviations 2,4-D 2,4-Dichlorophenoxyacetic acid - Kinetin 6-Furfurylaminopurine - 6-BAP 6-Benzylaminopurine - MS Murashige and Skoog Emrys Thomas died in England in May 1981.     

Genotype — environment interaction in tissue cultures of birch

Summary In vitro culture experiments were carried out with three birch genotypes characterized by certain genealogical relationships which serve as indicators of genetic similarity or dissimilarity. Each genotype was grown in each of six different environments (medium types), and callus growth and colour were observed. The aim was to improve our understanding of the operation of genetic and environmental effects at the early stages of regeneration in vitro. For this purpose we tried to answer the question as to whether genetic differences exert effects that are consistently distinguishable under different environments or whether environmental differences exert effects that are consistently distinguishable between different genotypes. Since conventional analytical methods, such as the analysis of variance, are inappropriate for providing satisfactory answers to this question, we applied a new concept of interpretation. With the help of this concept we obtained the following results which appear to be unique among their kind. 1) For both characters, callus growth and callus colour, genetic differences are masked only slightly by the environments while environmental differences are almost completely masked by the genotypes. Thus, in the present experiment, interaction is one-sided in the sense that environmental effects interact strongly with genotypic effects but genotypic effects interact only slightly with the environmental ones. 2) Nuclear effects seem to be responsible for the differences observed in callus growth, while the differences in callus colour can be explained by the joint action of nuclear and extranuclear effects.     

The Oswaldo Cruz Institute and its relationship with other biomedical research centers in São Paulo

This paper deals with the relationships between the Oswaldo Cruz Institute, a biomedical institution which was founded in Rio de Janeiro (Brazil) in the beginning of the 20th century, and other similar institutions founded in S?o Paulo during the same period, especially the Butantan and the Biological Institutes. The analysis comprehends the three first decades of the 20th century. The paper starts with a comparative presentation of the trajectory of these three institutions, showing the reasons which determined the great influence the Oswaldo Cruz Institute exerted on the other two. Then, it analyses these influences, principally on the basis of the interchange of researchers among the institutions. It concludes by showing that, due to the institutions' greater professionalization, these influences were increasingly turned into integration.     

Bacterial thiol oxidoreductases — from basic research to new antibacterial strategies

The recent, rapid increase in bacterial antimicrobial resistance has become a major public health concern. One approach to generate new classes of antibacterials is targeting virulence rather than the viability of bacteria. Proteins of the Dsb system, which play a key role in the virulence of many pathogenic microorganisms, represent potential new drug targets. The first part of the article presents current knowledge of how the Dsb system impacts function of various protein secretion systems that influence the virulence of many pathogenic bacteria. Next, the review describes methods used to study the structure, biochemistry, and microbiology of the Dsb proteins and shows how these experiments broaden our knowledge about their function. The lessons gained from basic research have led to a specific search for inhibitors blocking the Dsb networks.     

Biohydrogen production from microalgae—Major bottlenecks and future research perspectives

The imprudent use of fossil fuels has resulted in high greenhouse gas (GHG) emissions, leading to climate change and global warming. Reduction in GHG emissions and energy insecurity imposed by the depleting fossil fuel reserves led to the search for alternative sustainable fuels. Hydrogen is a potential alternative energy carrier and is of particular interest because hydrogen combustion releases only water. Hydrogen is also an important industrial feedstock. As an alternative energy carrier, hydrogen can be used in fuel cells for power generation. Current hydrogen production mainly relies on fossil fuels and is usually energy and CO₂-emission intensive, thus the use of fossil fuel-derived hydrogen as a carbon-free fuel source is fallacious. Biohydrogen production can be achieved via microbial methods, and the use of microalgae for hydrogen production is outstanding due to the carbon mitigating effects and the utilization of solar energy as an energy source by microalgae. This review provides comprehensive information on the mechanisms of hydrogen production by microalgae and the enzymes involved. The major challenges in the commercialization of microalgae-based photobiological hydrogen production are critically analyzed and future research perspectives are discussed. Life cycle analysis and economic assessment of hydrogen production by microalgae are also presented.     

Signaling pathways regulating blood–tissue barriers — Lesson from the testis

Signaling pathways that regulate blood–tissue barriers are important for studying the biology of various blood–tissue barriers. This information, if deciphered and better understood, will provide better therapeutic management of diseases particularly in organs that are sealed by the corresponding blood–tissue barriers from systemic circulation, such as the brain and the testis. These barriers block the access of antibiotics and/or chemotherapeutical agents across the corresponding barriers. Studies in the last decade using the blood–testis barrier (BTB) in rats have demonstrated the presence of several signaling pathways that are crucial to modulate BTB function. Herein, we critically evaluate these findings and provide hypothetical models regarding the underlying mechanisms by which these signaling molecules/pathways modulate BTB dynamics. This information should be carefully evaluated to examine their applicability in other tissue barriers which shall benefit future functional studies in the field. This article is part of a Special Issue entitled: Gap Junction Proteins edited by Jean Claude Herve.     

Biomedical engineering — Priorities for research in external aids

Some of the principal results and conclusions of a study to identify research priorities in the external aids field of Biomedical Engineering are presented. Particularly, there is the need for work on (1) the problems of permanent body access, (2) the development of improved membranes, (3) the harnessing of real-time speech analysis and speech synthesis technology and (4) specification of man/machine interfaces for the sensorially disabled. Lists of more specific research needs are given in which problems of the incontinent, the sensorially-impaired and the severely disabled are particularly prominent     

Food preferences and aversions in human health and nutrition: how can pigs help the biomedical research?

The establishment of food preferences and aversions determines the modulation of eating behaviour and the optimization of food intake. These phenomena rely on the learning and memory abilities of the organism and depend on different psychobiological mechanisms such as associative conditionings and sociocultural influences. After summarizing the various behavioural and environmental determinants of the establishment of food preferences and aversions, this paper describes several issues encountered in human nutrition when preferences and aversions become detrimental to health: development of eating disorders and obesity, aversions and anorexia in chemotherapy-treated or elderly patients and poor palatability of medical substances and drugs. Most of the relevant biomedical research has been performed in rodent models, although this approach has severe limitations, especially in the nutritional field. Consequently, the final aim of this paper is to discuss the use of the pig model to investigate the behavioural and neurophysiological mechanisms underlying the establishment of food preferences and aversions by reviewing the literature supporting analogies at multiple levels (general physiology and anatomy, sensory sensitivity, digestive function, cognitive abilities, brain features) between pigs and humans.     

Trace element contamination in feather and tissue samples from Anna’s hummingbirds

Trace element contamination (17 elements; Be, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Cd, Ba, Hg, Tl, and Pb) of live (feather samples only) and deceased (feather and tissue samples) Anna's hummingbirds (Calypte anna) was evaluated. Samples were analyzed using inductively coupled plasma-mass spectrometry (ICP-MS; 17 elements) and atomic absorption spectrophotometry (Hg only). Mean plus one standard deviation (SD) was considered the benchmark, and concentrations above the mean + 1 SD were considered elevated above normal. Contour feathers were sampled from live birds of varying age, sex, and California locations. In order to reduce thermal impacts, minimal feathers were taken from live birds, therefore a novel method was developed for preparation of low mass feather samples for ICP-MS analysis. The study found that the novel feather preparation method enabled small mass feather samples to be analyzed for trace elements using ICP-MS. For feather samples from live birds, all trace elements, with the exception of beryllium, had concentrations above the mean + 1 SD. Important risk factors for elevated trace element concentrations in feathers of live birds were age for iron, zinc, and arsenic, and location for iron, manganese, zinc, and selenium. For samples from deceased birds, ICP-MS results from body and tail feathers were correlated for Fe, Zn, and Pb, and feather concentrations were correlated with renal (Fe, Zn, Pb) or hepatic (Hg) tissue concentrations. Results for AA spectrophotometry analyzed samples from deceased birds further supported the ICP-MS findings where a strong correlation between mercury concentrations in feather and tissue (pectoral muscle) samples was found. These study results support that sampling feathers from live free-ranging hummingbirds might be a useful, non-lethal sampling method for evaluating trace element exposure and provides a sampling alternative since their small body size limits traditional sampling of blood and tissues. The results from this study provide a benchmark for the distribution of trace element concentrations in feather and tissue samples from hummingbirds and suggests a reference mark for exceeding normal. Lastly, pollinating avian species are minimally represented in the literature as bioindicators for environmental trace element contamination. Given that trace elements can move through food chains by a variety of routes, our study indicates that hummingbirds are possible bioindicators of environmental trace element contamination.