SIMS microscopy in the biomedical field.

We attempted to indicate the requirements for biomedical applications of SIMS microscopy. Sample preparation methodology should preserve both the structural and the chemical integrity of the tissue. Furthermore, it is often necessary to correlate ionic and light microscope images. This implies a common methodological approach to sample preparation for both microscopes. The use of low or high mass resolution depends on the elements studied and their concentrations. To improve the acquisition and processing of images, digital imaging systems have to be designed and require both ionic and optical image superimposition. However, the images do not accurately reflect element concentration; a relative quantitative approach is possible by measuring secondary ion beam intensity. Using an internal reference element (carbon) and standard curves the results are expressed in micrograms/mg of tissue. Despite their limited lateral resolution (0.5 microns) the actual SIMS microscopes are very suitable for the resolution of biomedical problems posed by action modes and drug localization in human pathology. SIMS microscopy should provide a new tool for metabolic radiotherapy by facilitating dose evaluation. The advent of high lateral resolution SIMS imaging (less than 0.1 microns) should open up new fields in biomedical investigation.     

Transgenic animals in biomedical research.

The advent of transgenic technology, in which foreign genetic information is stably introduced into the mammalian germ line, has dramatically enhanced our basic knowledge of physiologic and pathologic processes. Transgenic animals created by these genetic manipulations are being used to provide insights into gene regulation, development, pathogenesis, and the treatment of disease. Furthermore, transgenic biotechnology holds great promise for the creation of genetically superior livestock and the industrial production of precious pharmaceuticals. It is evident now that the study and use of transgenic animals will significantly improve the human condition.     

Trends in the use of nonhuman primates in biomedical programmes.

Recent surveys of the use of primates in biomedical laboratories indicate that the demand, especially for imported animals, is declining. Reasons for this trend are not clear, although restrictions on export by countries of origin undoubtedly have a significant effect. More precise survey techniques and terminology would aid comparisons and help to identify the factors involved in changes in demand.     

Synthetic oligonucleotides for biomedical applications.

New developments of oligonucleotides for biomedical applications are surveyed. Diagnostic probes were conveniently labelled by enzymatic immunogenic tailing with 5-bromo-deoxyuridine triphosphate. "Antisense" oligonucleotides of potential therapeutic value were stabilized against nucleolytic decay by inversion of terminal internucleotidic linkages. Introduction of 2'-deoxy-2'-fluoro-nucleotide units enhances duplex stability and conveys resistance to ribonucleases.     

Mining the biomedical literature in the genomic era: an overview.

The past decade has seen a tremendous growth in the amount of experimental and computational biomedical data, specifically in the areas of genomics and proteomics. This growth is accompanied by an accelerated increase in the number of biomedical publications discussing the findings. In the last few years, there has been a lot of interest within the scientific community in literature-mining tools to help sort through this abundance of literature and find the nuggets of information most relevant and useful for specific analysis tasks. This paper provides a road map to the various literature-mining methods, both in general and within bioinformatics. It surveys the disciplines involved in unstructured-text analysis, categorizes current work in biomedical literature mining with respect to these disciplines, and provides examples of text analysis methods applied towards meeting some of the current challenges in bioinformatics.     

Word sense disambiguation in the biomedical domain: an overview.

There is a trend towards automatic analysis of large amounts of literature in the biomedical domain. However, this can be effective only if the ambiguity in natural language is resolved. In this paper, the current state of research in word sense disambiguation (WSD) is reviewed. Several methods for WSD have already been proposed, but many systems have been tested only on evaluation sets of limited size. There are currently only very few applications of WSD in the biomedical domain. The current direction of research points towards statistically based algorithms that use existing curated data and can be applied to large sets of biomedical literature. There is a need for manually tagged evaluation sets to test WSD algorithms in the biomedical domain. WSD algorithms should preferably be able to take into account both known and unknown senses of a word. Without WSD, automatic metaanalysis of large corpora of text will be error prone.     

Taking the profit out of biomedical research tools.

A National Institutes of Health proposal will restrict the licensing of Federally funded biomedical research tools for commercial gain.     

Chemiluminescence microscopy as a tool in biomedical research.

Chemiluminescence has become a standard tool in biomedical research. Chemiluminescent probes are used for immunoassays, nucleic acid identification, reporter gene assays, measuring enzyme activity, and the detection of ions and small molecules such as Ca2+, ATP, NO, O2- and H2O2. Along with the development of new chemiluminescent probes, significant progress has been made in techniques to measure chemiluminescence. Ultra-sensitive photometers or luminometers have become widely available and can be obtained with automatic injectors and microplate readers. In addition, imaging photon detectors have been developed that allow the imaging of chemiluminescence from gels, blots, and microplates. Imaging photon detectors have also been attached to microscopes and allow imaging of chemiluminescent probes and reporter genes in cells and tissues. Specific methods of photon collection, storage, and analysis have been developed for microscopic imaging of chemiluminescence. Two of these methods are discussed in detail. The first is a method of data storage that allows days of continuous imaging without creating oversized files. The second is a method for calibrating photon imaging microscopes using a low-light standard. Such calibration will be helpful for comparing the performance of various photon imaging systems and for comparing data obtained in different laboratories.     

Promoting collaborations between biomedical scholars in the U.S. and sub-Saharan Africa

The premise of this piece is that a priority of international health should be to increase the number of investigators in the US and other developed countries who engage in research and other kinds of scholarly work in underdeveloped parts of the world, particularly sub-Saharan Africa where the overall disease burden is the highest and the gap in biomedical research infrastructure is the widest. The author's aim is to encourage medical students, resident doctors, and medical school faculty to devote a part of their career to teach, acquire clinical skills, or participate in research with health professionals at teaching hospitals in Africa. After briefly describing the thinking that led the author to Nigeria 30 years ago to teach and study biochemical aspects of health problems in rural and urban areas, he discusses some of the factors one needs to consider before entering into an international partnership, including identifying the right foreign collaborators, selecting a suitable research site, setting realistic goals, learning the local culture and indigenous language, and defining a theme for your program. Lastly, the piece points out potential pitfalls and problems that are often overlooked or underestimated in the early phases of planning an international partnership, including lukewarm institutional support at home, inflexible institutional review boards, dominance of the program by the US partner, maintaining continuity, and striking the right balance between scholarly work and humanitarian efforts. My hope is that US students and faculty in the health professions who read this piece will be stimulated and encouraged to consider how they might integrate into their curriculum or academic life visits lasting several months or more each year during which they would teach or train others or engage in research at a teaching hospital in some country in Africa.     

Sensitive magnetic sensors without cooling in biomedical engineering.

Magnetic field sensors are used in various fields of technology. In the past few years a large variety of magnetic field sensors has been established and the performance of these sensors has been improved enormously. In this review article all recent developments in the area of sensitive magnetic field sensory analysis (resolution better than 1 nT) are presented and examined regarding their parameters. This is mainly done under the aspect of application fields in biomedical engineering. A comparison of all commercial and available sensitive magnetic field sensors shows current and prospective ranges of application.     

Current considerations regarding reference units in the expression of biomedical data.

This paper discusses reference bases used in expressing biomedical data. The limitations and pitfalls of some modes of expression are discussed together with a reminder to investigators that each successful research effort depends as much on data expression as on design, methodology and statistics.     

Application of microspectrophotometry to biomedical research.

During recent years, the utilization of microspectrophotometry in biomedical research has increased at a rapid pace. This growth has been facilitated by both the advent of commercially available instruments which are reliable and manageable as well as improvements in histochemical techniques. This paper discusses the fundamental principles of visible light microspectrophotometry and important design criteria as well as briefly reviewing a wide range of applications. Special emphasis will be given to the Vickers M85 scanning integrating microspectrophotometer which is being routinely employed for both clinical and laboratory studies by a sizeable number of investigators.