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Computer method for the analysis of evoked motor unit potentials. 2. Duchenne, limb-girdle, facioscapulohumeral and myotonic muscular dystrophies.

Single motor unit potentials recorded from surface electrodes over the extensor digitorum brevis muscle and evoked by stimulation of the anterior tibial nerve at the ankle were obtained by a computer subtraction method. Their latencies, durations, amplitudes, and areas were measured in control subjects and patients with Duchenne, limb-girdle, facioscapulohumeral, and myotonic muscular dystrophy. Lateral popliteal motor nerve conduction velocities were also recorded. In the muscular dystrophies there was a significant increase in both the latencies and durations of motor unit potentials, the latter in notable contrast with the findings of conventional needle electromyography. Fastest motor conduction velocities were significantly reduced in the limb-girdle, facioscapulohumeral, and myotonic muscular dystrophy patients, while the shortest distal motor latencies were significantly prolonged in these patients and those with Duchenne muscular dystrophy. The results support the presence of a definitive neurogenic influence in the muscular dystrophies.

Adolescent

Baseline: a computer method of calculating baseline in fetal heart rate recordings.

'Baseline' estimation is of fundamental importance in both visual and numerical analysis of fetal heart rate recordings, even though the baseline itself is in reality an imaginary line. Here we describe a linear method of estimating baseline in fetal heart rate recordings. The method is easy to implement on a digital computer, and is capable of precise mathematical analysis. Non-linear methods, on the other hand, introduce unpredictable and non-quantifiable statistical bias, and are best avoided.

Computers

Computational methods for the screening of pharmacokinetic parameters in metabolism experiments.

A computational strategy is presented which is useful for the qualitative and quantitative assessment of reaction-kinetic parameters in a one-compartment open model for the metabolism of substances in a biological system, especially the metabolism of dialkylnitrosamines to the ultimate carcinogen. The mathematical model used is that of first order kinetics and results in Bateman-functions. The strategy allows to decide about stability or instability of a substance occurring in a chain of transformations. In the case of stability quantitative estimates of the half life are provided. The procedure compares parameter estimates from models of different qualitative nature. These estimates are derived by linear or non-linear regression methods.

Biotransformation

[Study of interventricular septal defects with equal aortic and pulmonary artery pressures. Classification by clinical and computer methods of 70 cases].

Application of various methods of classification to a group of 70 cases of ventricular septal defect with high pulmonary artery hypertension allowed a comparative study between the various methods aiming at distinguishing the forms with low from high pulmonary artery resistance. The reference clinical classification provides supplementary informations derived from the natural or post-operative course and eventually from the microscopic examination. The first automatic classification relies on the study of a single criterion: the pulmonary arteriolar resistance and the systemic resistance ratio. A second classification is based on the attribution of points to some clinical or haemodynamic signs resulting in a score orienting the classification of every individual. Multifactorial analysis methods deal with all the available informations for the overall group, and suppose the use of a computer. The informatic methods make it possible to study the classifying value of every sign. Correlations were established between these various techniques and the medical classification.

Adolescent

Simple computer method for equivalent square therapy field determination.

A simple BASIC computer program allows rapid determination of the equivalent squares of irregular radiation therapy fields. A port film or scale drawing of the irregular field is outlined manually on a spark tablet digitizer, and the side length of the square of equivalent area to perimeter ratio is rapidly calculated and returned by the computer.

Computers

Prediction and Evaluation of Protein Aggregation with Computational Methods.

Protein and peptide aggregation has recently become one of the most studied biomedical problems due to its central role in several neurodegenerative disorders and of biotechnological importance. Multiple in silico methods, databases, tools, and algorithms have been developed to predict aggregation of proteins and peptides to better understand fundamental mechanisms of various aggregation diseases. Here, we attempt to provide a brief overview of bioinformatic methods and tools to better understand molecular mechanisms of aggregation disorders. Furthermore, through a better understanding of protein aggregation mechanisms, it might be possible to design novel therapeutic agents to treat and hopefully prevent protein aggregation diseases.

Computational Biology

A new computer method for the storage and manipulation of DNA gel reading data.

This paper describes a new way of storing DNA gel reading data and an accompanying set of computer programs. These programs will perform all the manipulations that are required on data gained by the so-called 'shotgun' method of DNA sequencing. This system simplifies the computer processing involved with this sequencing method and also has the capability of being able at any time during a project to display, lined up in register, all the gel reading covering any section of the sequence.

Base Sequence

An improved secondary structure computation method and its application to intervening sequence in the human alpha-like globin mRNA precursors.

Current secondary structure prediction computations have a serious drawback. The calculated thermodynamically most stable structure often differs from that observed in solution or in crystal form. In this paper we suggest a way to partially over-come some of these limitations by simulating the RNA folding process and calculating the frequencies of occurrence of the various substructures obtained. The frequently recurring substructures are then selected to construct the secondary structure of the whole RNA. 142 tRNA molecules and an E. coli 16S rRNA molecule have been examined by this method. The percentage of successful prediction of the correct helices are significantly higher than those calculated previously. The secondary structures of intervening sequences (IVSs) excised from human alpha-like globin pre-mRNAs are also computed. Thus, in this method the secondary structures obtained are composed of the statistically more significant substructures. This has also been demonstrated by using randomly shuffled sequences. The secondary structures of each of the randomized sequences are computed and their mean and standard deviations are used in evaluating the significance of the substructures obtained in the folding of the biological sequence. Some potentially appealing structural features aligning adjacent exons for ligation have been found.

Base Sequence

A computer method for scanning and analysis of dot blots.

A system is described for computer analysis of autoradiograms produced from dot blots. The autoradiograms are first digitized on a rotating drum densitometer. The system automatically locates, integrates, and corrects the intensity of each spot for background. A linear range of exposures for each series of dilutions on the dot blot is calculated, and the amount of specific RNA is reported relative to other samples or to an internal standard. Without operator intervention, the system can directly scan and analyze all possible spots produced by the commercial filtration devices which use the geometry of a 96-well microtiter plate.

Computers

Simple computer method for evaluation of lateral diffusion coefficients from fluorescence photobleaching recovery kinetics.

A method is presented for the analysis of fluorescence photobleaching recovery curves. Based on the simplified kinetic expression of Yguerabide, J., J.A. Schmidt, and E.E. Yguerabide (1982, Biophys. J., 40:69-75), a linearization procedure is described that permits unequivocal determination of all diffusion parameters. The presence of additional membrane flow or multiple diffusion coefficients can easily be detected by this method, and simple corrections for the presence of these alternative recovery processes can be made by the use of a regular mini-computer. The validity of the method is tested on simulated recovery curves, varying the contribution of flow, multiple diffusion coefficients, and statistical noise due to counting error.

Diffusion