Combining different standards and different approaches for health information retrieval in a quality-controlled gateway

Internet as source of information is increasing in preeminence in numerous fields, including health. We describe in this paper the CISMeF project (acronym of Catalogue and Index of French-speaking Medical Sites) which has been designed to help the health information consumers and health professionals to find what they are looking for among the numerous health documents available online. The catalogue is founded on two standards: a set of metadata and a terminology based on the MeSH thesaurus which has the same structure and use as an ontology of the medical domain. The structure of the catalogue allows us to place the project at an overlap between the present Web, which is informal, and the forthcoming Semantic Web. Many features of information retrieval and navigation through the catalogue were developed. These features take into account the kind of the end-user (health professional, medical student, patient). The CISMeF-patients catalogue is a sub-catalogue of CISMeF and is dedicated to the patients and the general public. It shares the same model as CISMeF whereas MEDLINE and MedlinePlus do not. We also propose to couple two approaches (morphological processing and data mining) to help the users by correcting and refining their queries.     

Adolescence as a gateway to adult health outcomes

Adolescence has long been regarded as a transition from childhood to adulthood. More recently it is become a concern of those wishing to avoid adverse health outcomes during middle and late adulthood. Most of this effort has been focused on behavioural risk factors such as tobacco and excessive alcohol use, physical exercise habits, dietary habits, as well as sexual and injury-related behaviours. The concern is that these habits are established during adolescence, continue into adulthood, and come to constitute ongoing risk factors for adverse health outcomes during middle and late adulthood. There is good reason to criticize this approach. These behaviours are themselves shaped by adolescents’ living and working conditions and even then constitute a small proportion of the variance predicting adverse health outcomes during adulthood. More complex models of how adolescence serves as a gateway to adult health outcomes are presented. These are the socio-environmental, public policy, and political economy approaches. The argument is made that adolescence is a period during which public policy plays an especially important role in predicting future health outcomes. Yet, these public policies influence health all across the life span with adolescence providing only one of many important periods during which public policy shapes health prospects during middle and later adulthood. Ultimately one should consider a range of approaches ranging from the behavioural to the political to examine how adolescence serves as a gateway towards future adult prospects. An Adolescent Gateway Towards Adult Health Model is provided to assist in this process.     

The transparency of the mammalian cornea

1. A theoretical and experimental analysis of the relationship of the corneal stromal ultrastructure with light transmission has been made in an attempt to resolve recent contradictory explanations of corneal transparency.2. The spatial distribution of collagen fibrils in electronmicrographs of rabbit corneal stroma has been analysed in terms of a radial distribution function. The results indicate the presence of local order extending to at least 200 nm from individual fibrils.3. The observed spatial distribution of the collagen fibrils was used as a basis to compare the theoretically derived and the experimentally determined values of light transmission. It has been found that the transparency of the normal cornea may be explained by the quasi-random structure revealed by the electronmicroscope.4. Histograms of the collagen fibril diameter in normal rabbit corneal stroma revealed the range to be 12.5-32.5 nm and the mean value to be approximately 20 +/- 1.5 nm. Corneal swelling did not change the collagen fibril diameter significantly.5. It is concluded that the size and distribution of collagen fibrils revealed in electronmicrographs are consistent with the observed transparency of normal stromas.6. A marked heterogeneity in the spatial distribution of collagen fibrils was found in the swollen cornea. This is qualitatively consistent with the observed decrease in transparency.     

Myocardial Blood Flow in the Diving Seal

Grey seals exhibit a marked drop in heart rate, a slight decrease in ventricular contractility, and an essentially unchanged stroke volume upon diving. In the present study, we have demonstrated that the resulting drop in cardiac output is associated with a 90% reduction of coronary blood flow. Such reduction of myocardial blood flow takes place despite a significant increase in effective coronary driving pressure, and is indicative of a 800% increase in coronary vascular resistance. This means that the circulatory adjustments displayed by the diving seal (i.e. a reduction of the workload on the heart) are so effective that myocardial blood flow can be reduced to 10% of the pre-dive value without loss of cardiac function and blood pressure. It is suggested that even partial simulation of such a circulatory state might be a successful approach in the treatment of ischemic injuries in the heart of man.     

Malignant Meningioma of the Seal]

A nodule from the scalp of a 14-year-old boy was diagnosed by light and electron microscopy as a meningioma. There was no evidence of an intracranial lesion or involvement of the bone of the skull. The tumor was excised but recurred and metastasized to lung and chest wall.     

Stem cell research and the ethics of transparency

Stem cell research represents a field of scientific inquiry subject to intense public and political attention and debate worldwide. There are several reasons for this. First, it is a research endeavor surrounded by great expectations of future therapeutic benefits. Some of these expectations seem to be well founded, while others originate from adult and embryonic research enthusiasts having hyped their case. A second reason why this represents a field of public and political attention relates to deeply felt concerns regarding the moral justifiability of sacrificing potential human lives for research. The aim of this paper is to discuss different ways of making the performance of international embryonic stem cell research more transparent, and of unveiling the need for more open-minded dialog concerning the ethical costs of this research endeavor.     

Molecular genetics of the Finnish disease heritage.

Finland, located at the edge of the inhabitable world, is one of the best-studied genetic isolates. The characteristic features of population isolates-founder effect, genetic drift and isolation-have, over the centuries, shaped the gene pool of the Finns. Finnish diseases have been a target of extensive genetic research and the majority of some 35 disease genes enriched in this population have been identified; the molecular and cellular consequences of disease mutations are currently being characterized. Special strategies taking advantage of linkage disequilibrium have been efficiently used in the initial mapping and restriction of Finnish disease loci and this has stimulated development of novel statistical approaches in the disease gene hunt. Identification of mutated genes has provided tools for detailed analyses of molecular pathogenesis in Finnish diseases, many of which reveal a distinct tissue specificity of clinical phenotype. Often these studies have not only clarified the molecular detail of Finnish diseases, but also provided novel information on biological processes and metabolic pathways essential for normal development and function of human cells and tissues.     

Database for the mutations of the Finnish disease heritage

The Finnish disease heritage refers to a group of monogenic diseases that are enriched in the Finnish population due to founder effect and genetic isolation. The molecular genetics of these diseases has recently been intensely studied, and several founder and private mutations have been identified. The purpose of the present study was to create a database of the presently known mutations of the Finnish disease heritage. Hum Mutat 19:16–22, 2002. © 2001 Wiley‐Liss, Inc.     

Unique disease heritage of the Dutch-German Mennonite population

The Dutch-German Mennonites are a religious isolate with foundational roots in the 16th century. A tradition of endogamy, large families, detailed genealogical records, and a unique disease history all contribute to making this a valuable population for genetic studies. Such studies in the Dutch-German Mennonite population have already contributed to the identification of the causative genes in several conditions such as the incomplete form of X-linked congenital stationary night blindness (CSNB2; previously iCSNB) and hypophosphatasia (HOPS), as well as the discovery of founder mutations within established disease genes (MYBPC1, CYP17alpha). The Dutch-German Mennonite population provides a strong resource for gene discovery and could lead to the identification of additional disease genes with relevance to the general population. In addition, further research developments should enhance delivery of clinical genetic services to this unique community. In the current review we discuss 31 genetic conditions, including 17 with identified gene mutations, within the Dutch-German Mennonite population.     

Motion transparency and coherence in plaids: the role of end-stopped cells

Humans do not confound the motion of shadows cast upon a surface with the motion of the surface itself, although schemes that propose recombination of orientation-selective motion signals into a rigid motion percept of two-dimensional patterns would predict that they should do so. We propose a simple scheme that avoids recombination and instead attributes perception of two-dimensional pattern motion to the activation of orientation-selective end-stopped units that operate on the logarithm of the luminance. The proposed units respond to the change of contrast along a line, which typically occurs at an intersection. They are not active, however, when a shadow border intersects the edge of an object, because contrast does not change along either of these edges. Thus, end-stopped units signal the motion of transparent intersections weakly or not at all, and the independent motions of the shadow border and the object prevail. We tested two implications of this scheme, using plaids with variable intersection luminance. First, when the intersection luminance was such that it kept the contrast along the intersecting lines nearly constant, the sensitivity for the rigid plaid's direction of motion was minimal, and the sliding motion of the components prevailed. This occurred for light bars on dark backgrounds and for dark bars on light backgrounds. Thus, the effect of the intersection's luminance on the balance between the percepts of rigid-plaid motion and the motion of sliding components was independent of contrast inversion of bar and background. Secondly, when thin lines with the same luminance as the bars covered the borders of the intersection, the intersection's luminance did not affect the rigid-plaid motion percept very much, even when it corresponded to a transparent intersection. This indicates that, when the edges of the intersection and those of the bars were not collinear, the nulling of the endstopped units did not occur. This result is in line with physiological studies, which showed that the response of an end-stopped cell to a line is only partially inhibited when a similar line is presented non-collinearly with the first in the inhibitory end-zone of its receptive field. Our results are consistent with a scheme in which a second stage of motion detectors combines signals of orientation-selective end-free and orientation-selective end-stopped units for perception of the rigid motion of two-dimensional patterns.     

Genetic heritage of the Old Order Mennonites of southeastern Pennsylvania

The Old Order Mennonites of southeastern Pennsylvania are a religious isolate with origins in 16th-century Switzerland. The Swiss Mennonites immigrated to Pennsylvania over a 50-year period in the early 18th century. The history of this population in the United States provides insight into the increased incidence of several genetic diseases, most notably maple syrup urine disease (MSUD), Hirschsprung disease (HSCR), and congenital nephrotic syndrome. A comparison between the Old Order Mennonites and the Old Order Amish demonstrates the unique genetic heritage of each group despite a common religious and geographic history. Unexpectedly, several diseases in both groups demonstrate allelic and/or locus heterogeneity. The population genetics of the 1312T --> A BCKDHA gene mutation, which causes classical MSUD, are presented in detail. The incidence of MSUD in the Old Order Mennonites is estimated to be 1/358 births, yielding a corrected carrier frequency of 7.96% and a mutation allele frequency of 4.15%. Analysis of the population demonstrates that repeated cycles of sampling effects, population bottlenecks, and subsequent genetic drift were important in shaping the current allele frequencies. A linkage disequilibrium analysis of 1312T --> A mutation haplotypes is provided and discussed in the context of the known genealogical history of the population. Finally, data from microsatellite marker genotyping within the Old Order Mennonite population are provided that show a significant but modest decrease in genetic diversity and elevated levels of background linkage disequilibrium.