Proposed standard for image cytometry data files

A number of different types of computers running a variety of operating systems are presently used for the collection and analysis of image cytometry data. In order to facilitate the development of sharable data analysis programs, to allow for the transport of image cytometry data from one installation to another, and to provide a uniform and controlled means for including textual information in data files, this document describes a data storage format that is proposed as a standard for use in image cytometry. In this standard, data from an image measurement are stored in a minimum of two files. One file is written in ASCII to include information about the way the image data are written and optionally, information about the sample, experiment, equipment, etc. The image data are written separately into a binary file. This standard is proposed with the intention that it will be used internationally for the storage and handling of biomedical image cytometry data. The method of data storage described in this paper is similar to those methods published in American Association of Physicists in Medicine (AAPM) Report Number 10 and in ACR-NEMA Standards Publication Number 300-1985.     

The data quality foundation in OMNIITOX information system

Extended Summary Goal and Scope  This paper describes the data quality foundation for the OMNIITOX information system, with regard to data quality requirements and maintenance. Main Features  The data quality concept applied in the OMNIITOX project is based on results that are successfully used in other contexts (Fig. 1). Specific data quality requirements have been developed, which are applied in data acquisition and data review. The data quality requirements and quality maintenance is supported by the OMNIITOX concept model, which supplies a common language for the users from the different disciplines. Results and Discussion  The quality requirements and the concept model have been tested during data acquisition for the information system, and have been found to be a successful framework. The results from practical work demonstrate that it is possible to have a common understanding of the concept model and quality requirements. The user's experience the initial phase of learning the concepts and quality requirements as tedious. Nevertheless, experiences show that the users will benefit from the education during the further work. A considerable amount of data has been acquired based on the data quality foundation. Conclusions  The data quality foundation has been a successful framework for managing data quality in the design and establishment of the OMNIITOX information system. The data quality concept, the concept model, and specific quality requirements are applied as quality management tools to find, acquire, document, and interpret the information. Several quality issues deriving from interdisciplinary differences between the different users have been resolved, which facilitates a common understanding and reduces the risk of misinterpretations and misuse of information. Recommendations and Outlook  An important task for the finalization of the OMNIITOX project is to secure the credibility and long-term stability of the information system. The OMNIITOX information system will somewhat have less potential to support the toxicology related assessments in Europe if any of the involved disciplines chooses to reject or not to apply the concept model and the quality requirements.     

The use of brain slices in central nervous system pharmacology

Brain slice preparations have most frequently been employed to answer questions of a biochemical or physiological nature. Nevertheless, in vitro brain slices also have considerable value as pharmacological tools with which to study the physiological actions of neurotransmitters and drugs on the central nervous system. Several aspects of the slice preparation facilitate this type of analysis. Because drugs can be applied and tested in a relatively quantitative manner, many classical pharmacological techniques (e.g., dose-response curves, tests for competitive vs. noncompetitive antagonism) can be used to examine drug responses. At the simplest level, these techniques facilitate the differentiation of specific (primarily receptor-mediated) and nonspecific actions of drugs and neurotransmitters. As another consequence, the electrophysiological actions of drugs can be directly compared to their biochemical effects in vitro (receptor binding, activation or inhibition of adenylate cyclase, etc.). Ultimately, parallel studies of this type can be used to establish mechanisms of action for various neurotransmitters, particularly those that may employ biochemical substrates as second messengers. In this paper we describe in general terms many of the advantages of the slice preparation as a neuropharmacological tool. Some of the criteria useful in determining the involvement of various receptors in drug-induced changes in electrophysiological responses are discussed in detail. Finally, the responses of hippocampal slices to various adrenergic agents are used to illustrate the way in which various features of this preparation can be exploited pharmacologically. The results of these experiments constitute a significant advance in terms of our understanding of the neuropharmacology of catecholamine responses in this brain region.     

The use of a polyethyleneimine substrate for culturing dissociated cells of the central nervous system

A new method of preparation of polyethylenimin substrate for cultivation of dissociated cells from different parts of the central nervous system is presented. The alcohol solution of polyethylenimin used for this substrate is easily prepared, needs no sterilization and can be stored unlimitedly. The substrate provides a good attachment, growth and differentiation of neurons and glial cells and possesses all the advantages of more expensive polyaminoacid substrates (polylysine, polyornithine). Our substrate is highly adhesive, displays good optical properties and no artefacts after histological and histochemical treatment.     

The bacillary and macrophage response to hypoxia in tuberculosis and the consequences for T cell antigen recognition

Mycobacterium tuberculosis is a facultative anaerobe and its characteristic pathological hallmark, the granuloma, exhibits hypoxia in humans and in most experimental models. Thus the host and bacillary adaptation to hypoxia is of central importance in understanding pathogenesis and thereby to derive new drug treatments and vaccines.     

Maternal employment and childhood obesity: A search for mechanisms in time use data

A substantial body of research documents that maternal employment is associated with childhood obesity. This paper explores possible mechanisms for that correlation in the American Time Use Survey (ATUS). We find that maternal employment is associated with working mothers spending, per day, 4 fewer minutes grocery shopping, 17 fewer minutes cooking, 10 fewer minutes eating with children, 12 fewer minutes playing with children, 4 fewer minutes supervising children, and 37 fewer minutes caring for children. The differences tend to be greatest for mothers with young children (age 0–5 years). We explore the extent to which these findings differ by day of the week, whether a partner or spouse is present in the household, whether the mother works non-standard hours, and socioeconomic status. Only a small percentage (about 15%) of the fewer minutes spent in these activities by working mothers appears to be offset by increases in time by husbands and partners. These findings suggest plausible mechanisms for the association between maternal employment and childhood obesity.     

Pharmacological basis for the use of nimodipine in central nervous system disorders

Nimodipine, a Ca2+ antagonist with cerebrovasodilatory and anti-ischemic effects, binds to rat, guinea pig, and human brain membranes with high affinity (less than 1 nM). Only at higher concentrations has nimodipine been reported to block the release of some neurotransmitters and hormones from neuronal tissue. Nimodipine has no consistent effect on brain oxygen consumption or cortical ATP or phosphocreatine levels, although the ischemia-induced fall of brain ATP levels in gerbils or the lowering of intracellular brain pH in rabbits with focal cerebral ischemia were antagonized by the drug. In rats and baboons with middle cerebral artery occlusion, nimodipine was found to reduce neurological deficits without an increase in intracranial pressure or brain edema. Electrophysiological studies with nimodipine suggested a direct neuronal action. In rabbit dorsal root ganglion cells, concentrations as low as 20 nM were reported to block inward Ca2+ currents. Recent studies have suggested that nimodipine may also improve memory in brain-damaged or old rats, restore sensorimotor function and abnormal walking patterns of old rats, and accelerate acquisition of associative learning in aging rabbits. Blockade of age-related changes in Ca2+ fluxes in rat hippocampal neurones by nimodipine in vitro pointed to neuronal plasma membrane as the site of nimodipine action. The therapeutic usefulness of nimodipine appears not to be limited to cerebral ischemia, but may include dementia, age-related degenerative diseases, epilepsy, and ethanol intoxication.     

The anatomical pathways for antennal sensory information in the central nervous system of the cricket, Gryllus bimaculatus

Antennae are one of the major organs to detect chemo- and mechanosensory cue in crickets. Little is known how crickets process and integrate different modality of information in the brain. We thus used a number of different anatomical techniques to gain an understanding of the neural pathways extending from the antennal sensory neurons up to centers in the brain. We identified seven antennal sensory tracts (assigned as T1?C7) utilizing anterograde dye filling from the antennal nerve. Tracts T1?CT4 project into the antennal lobe (AL), while tracts T5 and T6 course into the dorsal region of the deutocerebrum or the suboesophageal ganglion, and finally, tract T7 terminates in the ventral area of flagellar afferent (VFA). By analyzing autofluorescence images of the AL, we identified 49 sexually isomorphic glomeruli on the basis of shape, relative position and size. On the basis of our sensory-tract data, we assigned the glomeruli into one of four separate groups. We then three-dimensionally reconstructed the internal structures in the AL (glomeruli) and the VFA (layers). Next in the protocerebrum, we identified both the tracts and their terminations from the AL and VFA. We found that 10 tracts originate in the AL, whereas there are at least eight tracts from the VFA. Several tracts from the AL share their routes with those from the VFA, but their termination areas are segregated. We now have a better anatomical understanding of the pathways for the antennal information in cricket.