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A program is described in this paper which uses a microcomputer and a digitizer for quantitative analysis of biological shape. The program is designed for practical use, it can measure shape parameters, make statistics of parameters and make significant tests.
A program to calculate the turnover rate of monoaminergic neurotransmitters was written for use on microcomputers. The program is based on non-steady state models, i.e., measuring the rate of change of levels of neurotransmitters or their metabolites after pharmacological inhibition of synthetic or degradative enzymes. Methods have been developed to estimate monoamine turnover by measuring the rate of decrease of catecholamine levels after treatment with alpha-methyl-p-tyrosine (AMPT), a tyrosine hydroxylase inhibitor, or the increase in serotonin levels after pargyline, an inhibitor of monoamine oxidase. This program is suitable for examining either linear increases or exponential decreases in monoamine levels. The program has been tested in our laboratory for the determination of serotonin, dopamine or norepinephrine turnover after hormonal or pharmacological manipulations. The program is readily adaptable for calculation of the turnover rate of other biological molecules under non-steady state conditions.
A simple microcomputer program in BASIC is designed to compute both the one-way and two-way analysis of variance. The program is an interactive one and can be easily and promptly used for statistical analysis of biomedical data. The applicability of the program is illustrated by data obtained from the percutaneous absorption of dihydroergotamine into the excised skin of rabbits.
Meta-analysis is increasingly being used in clinical research. While the meta-analytical algorithms for pooling the results of studies using non-censored end-points are now sufficiently standardized, the management of trials based on censored end-points is still controversial, and specific algorithms of meta-analysis are still needed (for example, censored end-points are commonly used in survival studies of cancer patients). In the present article we review the various algorithms that have thus far been utilized to perform a meta-analysis based on censored end-points, and we propose a new and original approach that combines two of the existing algorithms. Our approach is designed to formulate any meta-analysis of survival studies in terms of the calculation of an odds ratio. The meta-analytical odds ratio proposed here is called the 'log-rank' odds ratio of meta-analysis. A microcomputer program is described that implements the various methods of meta-analysis that can handle clinical trials based on censored end-points. Some examples are presented to illustrate the use of the program.
The use of a microcomputer in lung sound-analysis is described. The system was used experimentally in order to evaluate automated auscultation as a mean for improving the sensitivity of pulmonary health mass screening. The sound signals from four custom-made piezoelectric transducers, affixed at specific locations on the chest wall, and the breathing flow signal produced by a pneumotachograph were amplified, filtered and digitized simultaneously at 4000 Hz per channel for 512 ms. The acoustic data were transformed to the frequency domain to enable the calculation of the power spectra. Those were averaged over successive runs and displayed as log power vs. frequency. The operator could assess the convergence of the spectral pattern using the on-line graphics and calculated parameters, and store the data once the noise level had reached a preset level. This procedure was repeated during expiration, inspiration and on breath arrest. The results of the off-line analysis of the lung sounds, combined with pulmonary function tests and a questionnaire, were used to identify lung pathology.
A program for IBM-compatible microcomputers is described which facilitates the analysis and manipulation of voltage-clamp data. PCS accepts pCLAMP acquired data as well as data from a more generalized binary data file. This cursor-driven program permits four modes of analysis: peak detection, averaging, integration and curve fitting, with direct graphical feedback of the results. Graphs of analysis results, such as current versus voltage relations (I-V curves), with tabulated data can be concisely printed using a HP Laserjet III. Selected current traces may also be plotted using the HP Laserjet III or exported to an ASCII comma and quotation mark delimited file suitable for import to a spreadsheet program.
Opened in 1985, the J. Otto Lottes Health Sciences Library at the University of Missouri-Columbia has adapted to changes in information technology by installing a fiber optic backbone, establishing local area networks and file servers with databases and software programs, establishing a microcomputer learning laboratory, and responding to the needs of a problem-based learning curriculum. The library works cooperatively with the Medical Informatics Group, which is housed in the library and runs the micro laboratory, to support student and faculty computing.
A simple microcomputer crossover program in BASIC is designed for the purpose of drug bioequivalence studies and other related fields of statistical investigation. An illustration of the application of the program is presented to compare the bioavailability of ibuprofen when administered alone or followed by colestipol hydrochloride or by cholestyramine.
A microcomputer-based system for non-invasive monitoring of cardiovascular system in simulated microgravity is described. The system evaluates automatically, accurately and interactively heart beat intervals, beat-to-beat non-invasive finger arterial blood pressure (systolic, diastolic, mean and pulse pressure) using a Finapres device and beat-to-beat changes of thoracic blood volume using impedance changes. In addition, beat-to-beat evaluation of cardiac mechanical function including left ventricular ejection time, diastolic time, systolic time intervals, left ventricular ejection fraction estimate and several other contractility parameters, left ventricular volume, stroke volume and cardiac output estimates are performed with high degree of automaticity.
Cortical power spectrum (CPS) is a quantitative estimate of EEG spectral power density. The CPS provides suitably precise data for quantification and statistical inference compared to the qualitative evaluation of EGG when interpreted by clinicians or researchers. In the past decade, the CPS has been applied to the studies of cognitive functions, memory, psi phenomena, speech laterality, and states of consciousness including coma, sleep, anesthesia, pathophysiology and pain state. However, few systematic evaluations of CPS methodology have been reported, rendering cross-laboratory comparisons difficult and external validity of experimental results uncertain. This report first describes a calibration procedure employing a microcomputer system for measuring the functional relationship between input signals and output cortical powers. Second, we examine controlled behavioral artifact effects on the CPS. The behavioral artifacts observed in the CPS can provide a measurement anchor for less ambiguous interpretation of CPS experiments conducted in clinical or laboratory settings.
The eyeblink reflex is well suited for the study of habituation, sensitization, reflex modification and classical conditioning in humans. A microcomputer-based system for elicitation and recording of the eyeblink reflex is described. The system consists of three functional units: (1) an air-pressure bottle and pressure-reducing valves for delivery of air puffs to the eye in order to elicit the eyeblink reflex, and a CBM 64 computer for presentations of auditory stimuli in conjunction with air puffs; (2) a pair of light-emitting diodes and photocells placed in a pair of goggles placed on the subject for detection of eyeblinks; (3) an IBM-compatible personal computer, equipped with the ASYSTANT + software for eyeblink data acquisition and overall control of experiment and parameters. The system is presently in use in our laboratory, and technical details about the system can be obtained by writing to the first author.
An inexpensive multielectrode voltammetry system designed for in vivo neurochemical studies of the awake, unanesthetized primate has been developed. Consisting of an Apple II Plus microcomputer, parallel operational amplifier circuitry for six working electrodes, and commercially available interface boards, the system has the flexibility to implement many standard voltammetric procedures under total software control. Multielectrode monitoring is accomplished essentially simultaneously, and all channels are equipped with independent gain controls allowing for rapid amplification adjustment. An interactive chronoamperometry program, capable of making rapid 12 bit analog to digital conversions for each working electrode over four software selectable ranges, is described and system performance is evaluated.
A microcomputer based system is described for the analysis of various aspects of hippocampal field potential response recorded in vitro, either in the dendritic or somatic region. A comparison is made between the average amplitude and the time integral of synaptically evoked population spike at the cell body layer, following various intensities of stimuli delivered to the stratum radiatum. There was a good correlation between the two measures at low and intermediate intensities of stimulation. With stimulus intensities beyond those eliciting the population spike of maximal integral, the amplitude of the population spike further increased while its duration decreased. It is concluded that the integral provides a more accurate estimate of the extent of neuronal firing than the amplitude.
A data acquisition program is described for the Apple II series of microcomputers that allows for continuous, direct monitoring of electrographic elements from cortical, hippocampal and muscle leads from rats. The program detects cortical delta waves and sigma activity, hippocampal theta activity and electromyographic activity. The detected elements are counted and stored in memory at 15 second intervals (bins). Every three hours, the data are transferred to disks for permanent storage and off-line analysis.
A data acquisition and analysis system based on an Apple II microcomputer has been developed for use in sleep studies in the adult cat. The system reliably counts delta, spindle, and EMG waveforms, PGO waves, and REMs using amplitude and frequency criteria. These data can be used to algorithmically score sleep-wake state with high reliability (greater than 90% agreement with manual scoring). This method allows for automatic and quantitative analysis of selected EEG waveforms and sleep-wake states with less expense, more time savings, and greater convenience than manual scoring.
A microcomputer-based system is described that detects, counts and stores cortical delta and sigma waves, hippocampal theta waves and electromyographic activities in the rat by building matrices with the incidence of those four variables (columns) in 15-second bins (rows). Data tables are submitted to statistical, graphics and spread-sheet software to assess internal organization of sleep episodes and 24-hour distribution of sleep variables. Within sleep episodes, cross-correlograms reveal a delta-sigma-theta sequence, while autocorrelograms quantify clustering and periodicity of variables. Sleep accumulates in the lights-on phase, with high concentration of delta at the beginning of this sleep-predominant phase and of sigma and theta in its second half. These are notable similarities with human sleep architecture. Simple procedures for data reduction into standard behavioral state diagnosis are demonstrated. The low cost of personal computers and data acquisition interfaces facilitates the automation of complex paradigms by ad hoc on-line programs that produce as output a data base that can be processed by standard software, providing a fluid pathway of automated acquisition, analysis and presentation of data.
We describe a plasmid map program which runs on an IBM PC microcomputer and facilitates the drawing of circular plasmid maps. The user enters information from the keyboard in the form of restriction enzyme sites, genes and their locations, and other plasmid markers such as promoters, origins, or other sites. This information can then be stored in a file for future reference. The plasmid map can be displayed on the screen, printed on a dot-matrix printer, or plotted on a Hewlett Packard HP7475A plotter.
Maps of genetic linkage and restriction enzyme cleavage sites can be quickly prepared on an IBM PC microcomputer with the commercially available program Lotus 1-2-3. Data can be entered on the keyboard or imported from other programs. The maps can be displayed on the screen or with a printer or plotter. These procedures should be useful in the research laboratory, in preparing figures for publication and in teaching.