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Quality management, certification and rating of health information on the Net with MedCERTAIN: using a medPICS/RDF/XML metadata structure for implementing eHealth ethics and creating trust globally.

MedCERTAIN (MedPICS Certification and Rating of Trustworthy Health Information on the Net, http://www.medcertain.org/) is a recently launched international project funded under the European Union's (EU) "Action Plan for safer use of the Internet". It provides a technical infrastructure and a conceptual basis for an international system of "quality seals", ratings and self-labelling of Internet health information, with the final aim to establish a global "trustmark" for networked health information. Digital "quality seals" are evaluative metadata (using standards such as PICS=Platform for Internet Content Selection, now being replaced by RDF/XML) assigned by trusted third-party raters. The project also enables and encourages self-labelling with descriptive metainformation by web authors. Together these measures will help consumers as well as professionals to identify high-quality information on the Internet. MedCERTAIN establishes a fully functional demonstrator for a self- and third-party rating system enabling consumers and professionals to filter harmful health information and to positively identify and select high quality information. We aim to provide a trustmark system which allows citizens to place greater confidence in networked information, to encourage health information providers to follow best practices guidelines such as the Washington eHealth Code of Ethics, to provide effective feedback and law enforcement channels to handle user complaints, and to stimulate medical societies to develop standard for patient information. The project further proposes and identifies standards for interoperability of rating and description services (such as libraries or national health portals) and fosters a worldwide collaboration to guide consumers to high-quality information on the web.

Certification↗

[[Projection of household conditions of the elderly in Japan]].

"The household condition of the elderly [in Japan]...was estimated for the years 1975, 1980, 1985 and 1990, and was projected for the years 1995, 2000, 2005 and 2010, using the population census tabulations and the future population by age and sex projected in 1992.... The population aged 65 and over belonging to a 'couple only household' (5,905 thousand) is projected to surpass the population belonging to a 'household with their child' (4,260 thousand) in 2010 for males, while the latter will be...more (6,812 thousand) than the former (5,115 thousand) for females in the same year. The elderly population aged 65 and over in one-person households is projected to increase more remarkably for males than females." (SUMMARY IN ENG)

Adult↗

Identification of dopaminergic neurons of nigral and ventral tegmental area subtypes in grafts of fetal ventral mesencephalon based on cell morphology, protein expression, and efferent projections.

Transplants of fetal ventral mesencephalic tissue are known to contain a mixture of two major dopamine (DA) neuron types: the A9 neurons of the substantia nigra pars compacta (SNpc) and the A10 neurons of the ventral tegmental area (VTA). Previous studies have suggested that these two DA neuron types may differ in their growth characteristics, but, because of technical limitations, it has so far been difficult to identify the two subtypes in fetal ventral mesencephalon (VM) grafts and trace their axonal projections. Here, we have made use of a transgenic mouse expressing green fluorescent protein (GFP) under the tyrosine hydroxylase promoter. The expression of the GFP reporter allowed for visualization of the grafted DA neurons and their axonal projections within the host brain. We show that the SNpc and VTA neuron subtypes in VM grafts can be identified on the basis of their morphology and location within the graft, and their expression of a G-protein-gated inwardly rectifying K+ channel subunit (Girk2) and calbindin, respectively, and also that the axonal projections of the two DA neuron types are markedly different. By retrograde axonal tracing, we show that dopaminergic innervation of the striatum is derived almost exclusively from the Girk2-positive SNpc cells, whereas the calbindin-positive VTA neurons project to the frontal cortex and probably also other forebrain areas. The results suggest the presence of axon guidance and target recognition mechanisms in the DA-denervated forebrain that can guide the growing axons to their appropriate targets and indicate that cell preparations used for cell replacement in Parkinson's disease will be therapeutically useful only if they contain cells capable of generating the correct nigral DA neuron phenotype.

Age Factors↗

Hand-held three-dimensional dental X-ray system: technical description and preliminary results.

OBJECTIVE: To design, fabricate, and perform preliminary in vitro testing of a portable, hand-held, three-dimensional (3D) dental X-ray system using options unique to Tuned-Aperture Computed Tomography (TACT). The design allows for task-specific positioning over an unlimited range of user-selected angles and incorporates an integrated laser guidance system to constrain the focal-object distance. METHODS: A prototype system was fabricated consisting of an extremely lightweight X-ray source cantilevered from an aluminum gunstock-type handle to which a transparent radiation scatter shield was attached. Aiming was facilitated by task-specific visual cues used in conjunction with a spherically shaped radiolucent alignment jig coupled to the tissues of interest. Proper range was assured by a laser-assisted guidance system. The image transducer was an extrinsically modified commercially available CMOS device. The irradiated patient was simulated by a DXTTR phantom. RESULTS: The prototype demonstrated automated display of radiographed intra-oral tissues in three dimensions from arbitrary projection geometries and simulated task-specific sequences. Uncontrolled movements between exposures produced no obvious degeneration of 3D image quality. The aiming system minimized technical errors from misangulation. All dental regions in the phantom were imaged without difficulty. Projected risk was observed to be within clinically acceptable limits. CONCLUSIONS: Task-specific 3D images can be generated from as few as three uncontrolled projections. Total exposures can be prorated to levels not greatly exceeding those required for conventional two-dimensional radiographs of comparable image quality. Predicted radiation risks lie well below existing guidelines for occupational exposure.

Dental Equipment↗

The impact of demographic change on tax revenue.

"This paper [simulates] the impact of demographic change on direct tax revenue for the Netherlands using extensive survey data and population projections. Projected demographic development in the Netherlands fits in well with the OECD mainstream. The analysis thus has a more general relevance. The simulations indicate a 27 percent rise in tax revenue until 2010 because of population growth and a relatively older labor force. After 2030, revenue falls as a consequence of a declining population and a rapidly rising share of the elderly. The authors also simulated a variant in which labor-force participation rates are set on the substantially higher OECD average. In this case, the increase in tax revenue almost doubles as compared to the base variant."

Demography↗

Projecting the number of new AIDS cases in the United States.

"This paper reviews the two leading methods used to project the number of AIDS cases: back calculation and extrapolation. These methods are assessed in light of key features of the HIV/AIDS epidemic and of data on the epidemic; they are also assessed in terms of the quality of the projections they yield. Our analysis shows that both methods have tended to overproject, often by sizable amounts, the number of AIDS cases in the United States....A new method for projecting AIDS cases is proposed that exploits knowledge about the process generating AIDS cases and that incorporates readily available information about rates of new HIV infection.... Relative to the method of extrapolation, this method projects 22,000 fewer new AIDS cases for 1995 (a 36% difference). This method also projects that intravenous drug users will replace homosexual/bisexual men as the dominant transmission category for AIDS."

Acquired Immunodeficiency Syndrome↗

[Population forecasts in 1980, an analysis of mortality by cause of death].

The methods of projecting future mortality in official forecasts of population growth in the Netherlands are described. In particular, it is noted that the projected sex, age, and marital status specific death rates were not split up by causes of death. An analysis of mortality from 1980 to 1990 is presented, and it is shown that "the life expectancies calculated for extrapolated death rates split up by group of causes of death hardly differ from those where such a split up is not made. According to the figures presented...the differences never exceed 0.2 years. From these figures it cannot be concluded that splitting up the death rates by groups of causes of death in the national population forecasts would lead to significantly different results as far as mortality is concerned." (summary in ENG)

Cause of Death↗

Evaluating the forecast accuracy and bias of alternative population projections for states.

"A common perception among producers (and users) of population projections is that complex and/or sophisticated techniques produce more accurate forecasts than simple and/or naive techniques. In this paper we test the validity of that perception by evaluating the forecast accuracy and bias of eight commonly used projection techniques drawn from...four categories [trend extrapolation, ratio extrapolation, cohort-component, and structural]. Using data for [U.S.] state population projections from a number of different time periods, we find no evidence that complex and/or sophisticated techniques produce more accurate or less biased forecasts than simple, naive techniques."

Americas↗

The status of the Spanish language in the United States at the beginning of the 21st century.

"This study presents population projections for different linguistic components of the Spanish language group, that is, for English dominant bilinguals, Spanish dominant bilinguals and Spanish monolinguals [in the United States]. The population model combines parameters obtained from the U.S. Bureau of the Census for nonlinguistic characteristics with linguistic parameters estimated from the 1976 Survey of Income and Education. The number of persons speaking Spanish on a regular basis will climb to an estimated 16.6 million persons at the turn of the century. Further analysis reveals, however, that an additional 4.5 million persons will have left the group by ceasing to speak Spanish. In fact, in the absence of continued immigration, this language minority cannot maintain its current size and will undergo progressively more rapid decline over the course of time."

Americas↗

Sequence variation database project at the European Bioinformatics Institute.

The sequence variation project at EBI aims to create a unified resource for browsing and searching sequence differences. Technical advances in reading in new data types and in validating and cross-referencing entries are reported. It is suggested that the hardest problems in unifying mutation databases are related to intellectual property rights. The concept of copylefting is introduced as a potential solution to these.

Computational Biology↗

Diffusion tensor fiber tracking of human brain connectivity: aquisition methods, reliability analysis and biological results.

We present a description, biological results and a reliability analysis for the method of diffusion tensor tracking (DTT) of white matter fiber pathways. In DTT, diffusion-tensor MRI (DT-MRI) data are collected and processed to visualize the line trajectories of fiber bundles within white matter (WM) pathways of living humans. A detailed description of the data acquisition is given. Technical aspects and experimental results are illustrated for the geniculo-calcarine tract with broad projections to visual cortex, occipital and parietal U-fibers, and the temporo-calcarine ventral pathway. To better understand sources of error and to optimize the method, accuracy and precision were analyzed by computer simulations. In the simulations, noisy DT-MRI data were computed that would be obtained for a WM pathway having a helical trajectory passing through gray matter. The error vector between the real and ideal track was computed, and random errors accumulated with the square root of track length consistent with a random-walk process. Random error was most dependent on signal-to-noise ratio, followed by number of averages, pathway anisotropy and voxel size, in decreasing order. Systematic error only occurred for a few conditions, and was most dependent on the stepping algorithm, anisotropy of the surrounding tissue, and non-equal voxel dimensions. Both random and systematic errors were typically below the voxel dimension. Other effects such as track rebound and track recovery also depended on experimental conditions. The methods, biological results and error analysis herein may improve the understanding and optimization of DTT for use in various applications in neuroscience and medicine.

Adult↗

Digital area measurement of fundus landmarks.

PURPOSE: To present and validate an image analysis technique for the calculation of the true projection area of fundus landmarks from a digital fundus image. The authors present the description, technical details and results of the study. METHODS: Experimental study using a calibrated Gullstrand-type model eye with a scale of half circles in the centre of the artificial fundus. The axial length of the model eye was set to different values ranging from 21 mm to 29 mm, and the area of a half circle was calculated from digital fundus images with a magnification-calibrated image analysis program (UTHSCSA Image Tool). The calibration was based on Littmann's formula for correcting the magnification of fundus images. RESULTS: The maximum deviation of the calculated area size from the true fundus object area was -3.7% under myopic and +3.4% under hyperopic conditions. The 95% confidence interval for repeated area measurements was from +1.83 to -1.46%. CONCLUSIONS: The magnification-calibrated image analysis technique based on Littmann's formula is a non-invasive, accurate and reproducible tool for true area measurement of fundus landmarks.

Calibration↗

Chains of damages and failures in a metropolitan environment: some observations on the Kobe earthquake in 1995.

The interaction and the couple effects that may occur as induced and indirect consequences of any triggering hazard in metropolitan areas is one of the most important problems to be tackled during disasters, as the Kobe earthquake in 1995 showed very clearly. The analysis of direct, secondary and indirect effects of the Kobe earthquake suggests to substitute the concept of chain of losses and failures to the simple couple hazardous event-damages which is currently used. Not only parameters related to physical weakness or strength of the built environment should be considered by scientists, experts and decision-makers. Organisational, social, and systemic factors are equally crucial to understand the magnified dimension of disasters at increasing levels of exposed systems vulnerability. Linking failures due to different kinds of vulnerability one to the other permits to reconstruct complete event scenarios, where social and organisational elements are not simply added to the 'hard' components of cities, but contribute to explain why failures and losses occurred and why it took so long to repair them. Lifeline damage assessment provides a good example to show how physical, organisational and systemic vulnerabilities are intimately connected one to the other. The point of view from which governance problems related to prevention and emergency preparedness will be looked at is that of an urban and regional planner. When planners look for design solutions suitable for a specific town or region, they must constantly bridge between hard technical matters and social and economical concerns. Furthermore, they are forced to consider in their projects spatial and geographic dimensions. Those two typical features of planners' approach to problem solving can be interesting for scholars in the field of risk assessment and mitigation research.

Disaster Planning↗

Multiple neuroanatomical tracing in primates.

The present report deals with a multiple tract-tracing procedure in non-human primates enabling the simultaneous visualization of retrogradely transported Fluoro-Gold (FG) and cholera toxin B subunit (CTB) in combination with anterogradely transported biotinylated dextran amine (BDA). Two issues have played key roles on the achievement of this reliable procedure: first, the recent development of a commercial antiserum against FG that allows us to convert the original fluorescent signal of this dye in a permanent precipitate via standard peroxidase-anti-peroxidase methods; second, the introduction of the novel peroxidase substrate Vector(R) VIP (V-VIP), resulting in a purple precipitate. The combination of these neuroanatomical tracers in one and the same histological section opens a possibility for the permanent visualization of the convergence of inputs from a particular brain area onto identified, two different subsets of projection cells of another area. Furthermore, this combination of three tracers emerges as a powerful technical tool for obtaining broad amounts of complementary data regarding the monkey brain connectivity, thus significantly reducing the number of animals needed to complete a particular study.

Animals↗

Hydrothermal treatment and malting of barley improved zinc absorption but not calcium absorption in humans.

OBJECTIVE: To study whether hydrothermal treatment or malting of barley (cv. Blenheim) improves zinc and calcium absorption in humans. DESIGN: : Two groups of 10 and 12 healthy subjects, respectively, were in a period of 2 months in a fasting state, served two single meals each containing porridge or breakfast cereals prepared from processed or unprocessed (control) barley (60 g). The meals included 200 g of milk, extrinsically labelled with (65)Zn and (47)Ca. Whole-body retention of both minerals was measured. SETTING: The study was carried out at the Department of Radiation Physics, Sahlgrenska University Hospital, Göteborg. SUBJECTS: The subjects were recruited among students at the Göteborg University. None dropped out. INTERVENTIONS: The activities of (65)Zn and (47)Ca were measured by whole-body counting four to five times over a 4-week period after each meal. RESULTS: Zinc absorption from hydrothermally treated barley porridge, containing 28 mg P as inositol tri- to hexaphosphates (InsP(3)-InsP(6)), was significantly higher (P<0.001) than from control porridge containing 111 mg P as InsP(3)-InsP(6), 25.2+/-6.9 vs 11.0+/-2.5% (n=12). Calcium absorption did not differ (P>0.05), 21.1+/-6.8 vs 19.5+/-4.7% (n=12). Zinc absorption from breakfast cereals of malted barley with phytase activity and containing 70 mg P as InsP(3)-InsP(6,) was significantly higher (P<0.05) than from flakes of barley, containing 108 mg P as InsP(3)- InsP(6) and no phytase activity, 22.9+/-5.8 vs 14.8+/-4.6% (n=10). The calcium absorption was 21.3+/-6.5 vs 18.5+/-4.3% (n=10) and did not differ significantly (P>0.05). CONCLUSION: Improvements of zinc absorption in breakfast meals can be achieved by optimised hydrothermal treatment or malting of barley. Calcium absorption was not influenced in the meals in this study. SPONSORSHIP: Supported by Semper AB, Sweden, Oy Lahden Polttimo, Finland, the SL-Foundation, Sweden, Swedish National Board for Industrial and Technical Development (NUTEK), the Nordic Industrial Foundation, Swedish Council for Forestry and Agricultural Research (SJFR, project no 50.0306/97).

Adolescent↗

The COIN workstation: state of the future art.

This is a description of the clinical workstation now under development by the Clinical Oncology Information Network (COIN) Project at the Clinical Oncology Centre, North Middlesex Hospital, London, UK. It comprises: introduction; background; technical requirements; design; what the workstation does; how the workstation does it; future plans; glossary; and 26 figures showing screen shots of the workstation in use. The following article sets out the guidance on the creation of evidence-linked guidelines issued to the COIN Specialty Working Groups charged in 1995 with producing clinical guidelines for breast, colorectal, lung, prostate and testicular cancer and generic guidelines for the delivery of radio- and chemotherapy on behalf of the Faculty of Clinical Oncology of The Royal College of Radiologists and the Joint Council for Clinical Oncology. The first of these guidelines, for lung cancer, is published elsewhere in this issue.

Computer Systems↗

[Private umbilical cord blood banking does not reduce the number of samples for scientific stem cell research].

OBJECTIVE: Private umbilical cord blood (UCB) banking after delivery has increased over the last decade. For adult/somatic stem cell research UCB is an essential source of stem cells and researchers question if the number of UCB samples for research might be reduced by private banking. METHODS: A survey among seven private blood banks in Germany and analysis and comparison of the number of UCB samples donated for research within the STEMMAT project with private blood banking were performed from 03/2003 to 06/2005 at the Frauenklinik (OB/GYN), Technical University Munich, Germany. RESULTS: Within 27.5 months 1,551 UCB samples were collected for research purposes; the effective recruitment rate was higher than expectations at an effective 66.2 %. Private UCB banking [n = 24] was distributed among three cord blood banks [n = 16, 6 and 4]. The rate of private blood banking was 0.99 % for all deliveries, thus reducing the effective rate for research purpose by only 1.5 %. CONCLUSION: Under the assumption of active and successful recruitment of scientific UCB samples, private blood banking does not significantly reduce this rate and therefore is a negligible rival in the competition for sufficient numbers of UCB samples for research.

Blood Banks↗