The role of radiation therapy in benign diseases.

Although adequate prospective data are lacking, radiation therapy seems to be effective for many benign diseases and remains one of the treatment modalities in the armamentarium of medical professionals. Just as medication has potential adverse effects, and surgery has attendant morbidity, irradiation sometimes can be associated with acute and chronic sequelae. In selecting the mode of treatment, most radiation oncologists consider the particular problem to be addressed and the goal of therapy in the individual patient. It is the careful and judicial use of any therapy that identifies the professional. With an understanding of the current clinical data, treatment techniques, cost, and potential detriment, the goal is to provide long-term control of the disease while minimizing unnecessary treatment and potential risks of side effects. The art lies in balancing benefits against risks.

Application of SEMG in computer mouse access for the disabilities.

PURPOSE: To improve the operating speed of the traditional row-column scanning computer keyboard-mouse composite panel controlled using a single key. METHOD: Using a single mouse input control window can avoid scanning unnecessary keyboard characters, thereby increasing the speed in performing mouse commands. In addition, the surface electromyographic (SEMG) sensing input can also be used to provide an input option for the disabled. RESULTS: Eleven volunteers operated the single mouse input control window using the SEMG input and the traditional computer keyboard-mouse composite panel controlled using a single key. The average operating times were 121.3+/-8.9 sec and 208.6+/-10.7 sec, respectively. The difference was statistically significant (p<0.05). CONCLUSIONS: The row-column scanning method with the single mouse control window using SEMG input can effectively decrease the operating time. Through this system, the disabled can operate a computer and lead an independent life.

A radio controller using speech for the blind.

This article describes a low-cost, portable real-time DSP-based speech controller system to provide radio interface control command applications for the blind. The system recognizes spoken Mandarin Chinese words on a DSP chip (TMS320C31) using a hidden Markov model. The function of the radio set, which includes a tuner, tape, and compact disc, were evaluated under both noisy and noiseless environments. Four subjects took part in the experiment and achieved 83 and 90% mean recognition rates under noisy and noiseless conditions, respectively. In addition, because this system is based on a DSP chip, it can easily be programmed to execute speaker-independent algorithms.

Isokinetic elbow joint torques estimation from surface EMG and joint kinematic data: using an artificial neural network model.

Because the relations between electromyographic signal (EMG) and anisometric joint torque remain unpredictable, the aim of this study was to determine the relations between the EMG activity and the isokinetic elbow joint torque via an artificial neural network (ANN) model. This 3-layer feed-forward network was constructed using an error back-propagation algorithm with an adaptive learning rate. The experimental validation was achieved by rectified, low-pass filtered EMG signals from the representative muscles, joint angle and joint angular velocity and measured torque. Learning with a limited set of examples allowed accurate prediction of isokinetic joint torque from novel EMG activities, joint position, joint angular velocity. Sensitivity analysis of the hidden node numbers during the learning and testing phases demonstrated that the choice of numbers of hidden node was not critical except at extreme values of those parameters. Model predictions were well correlated with the experimental data (the mean root-mean-square-difference and correlation coefficient gamma in learning were 0.0290 and 0.998, respectively, and in three different speed testings were 0.1413 and 0.900, respectively). These results suggested that an ANN model can represent the relations between EMG and joint torque/moment in human isokinetic movements. The effect of different adjacent electrode sites was also evaluated and showed the location of electrodes was very important to produce errors in the ANN model.

A neuro-control system for the knee joint position control with quadriceps stimulation.

A neuro-control system was designed to control the knee joint to move in accordance with the desired trajectory of movement through stimulation of quadriceps muscle. This control system consisted of a neural controller and a fixed parameter proportional-integral-derivative (PID) feedback controller, which was designated as a neuro-PID controller. A multilayer feedforward time-delay neural network was used and trained as an inverse model of the functional electrical stimulation (FES)-induced quadriceps-lower leg system for direct feedforward control. The training signals for neural network learning were obtained from experimentation using a low-pass filtered random sequence to reveal the plant characteristics. The Nguyen-Widrow method was used to initialize the neural connection weights. The conjugate gradient descent algorithm was then used to modify these connection weights so as to minimize the errors between the desired outputs and the network outputs. The knee joint angle was controlled with only small deviations along the desired trajectory with the aid of the neural controller. In addition, the PID feedback controller was utilized to compensate for the residual tracking errors caused by disturbances and modeling errors. This control strategy was evaluated on one able-bodied and one paraplegic subject. The neuro-PID controller showed promise as a position controller of knee joint angle with quadriceps stimulation.

Biochemical and genetic characterization of multiple splice variants of the Flt3 ligand.

We have performed a comprehensive analysis of cell lines and tissues to compare and contrast the expression patterns of Flt3 ligand (FL), c-Kit ligand (KL), and macrophage colony-stimulating factor as well as their receptors, Flt3, c-Kit, and c-Fms. The message for FL is unusually ubiquitous, whereas that of its receptor is quite restricted, apparently limiting the function of the ligand to fetal development and early hematopoiesis. We have also sequenced a mouse FL genomic clone, revealing how the three splice variant FL mRNAs that we have isolated arise. The chromosomal location of the FL gene has been mapped, by in situ hybridization, to chromosome 7 in mouse and chromosome 19 in human. Natural FL protein has been purified from a stromal cell line and shown to be a 65 kD nondisulfide-linked homodimeric glycoprotein comprised of 30 kD subunits, each containing 12 kD of N- and O-linked sugars. Pulse-chase experiments show that one of the splice variants (T110) is responsible for producing the bulk of soluble FL, but only after it has first been expressed at the cell surface as a membrane-bound form. The other splice-variant forms produce molecules that are either obligatorily soluble (T169) or membrane-bound but released only very slowly (T118). Finally, even though most cell lines express some amount of FL mRNA, we found that very little FL protein is actually made, with T cells and stromal cells being the major producers. The data suggests that FL plays its roles over very short distances, perhaps requiring cell-cell contact.

Real-time implementation of electromyogram pattern recognition as a control command of man-machine interface.

The purpose of this study was to develop a real-time electromyogram (EMG) discrimination system to provide control commands for man-machine interface applications. A host computer with a plug-in data acquisition and processing board containing a TMS320 C31 floating-point digital signal processor was used to attain real-time EMG classification. Two-channel EMG signals were collected by two pairs of surface electrodes located bilaterally between the sternocleidomastoid and the upper trapezius. Five motions of the neck and shoulders were discriminated for each subject. The zero-crossing rate was employed to detect the onset of muscle contraction. The cepstral coefficients, derived from autoregressive coefficients and estimated by a recursive least square algorithm, were used as the recognition features. These features were then discriminated using a modified maximum likelihood distance classifier. The total response time of this EMG discrimination system was achieved about within 0.17 s. Four able bodied and two C5/6 quadriplegic subjects took part in the experiment, and achieved 95% mean recognition rate in discrimination between the five specific motions. The response time and the reliability of recognition indicate that this system has the potential to discriminate body motions for man-machine interface applications.

An open trial of venlafaxine in the treatment of attention-deficit/hyperactivity disorder in children and adolescents.

A 5-week open trial of venlafaxine was conducted in 16 children and adolescents (mean age 11.6 years) with attention-deficit/hyperactivity disorder (ADHD) in order to estimate the appropriate dosage range and to determine the extent of side effects. Subjects were evaluated using a structured clinical interview and a computerized diagnostic assessment, and subjects diagnosed with ADHD and without comorbid depression were asked to enter the study. Conners Parent Rating Scale (CPRS) and Conners Continuous Performance Test (CPT) were performed at baseline and at the end of the 5-week trial. Two subjects were lost to follow-up. Of the remaining 14 patients, 7 subjects displayed a decrease of at least one standard deviation from their baseline on one of the CPRS subscale scores and had subjective reports from parents of improved behavior. There were no statistically significant effects of venlafaxine on reaction times or on the number of commission and omission errors on CPT. Three ADHD subjects displayed a worsening of their hyperactivity and required discontinuation of venlafaxine, and nausea led to drug discontinuation in 1 patient. The mean daily dose of venlafaxine was 60 mg (1.4 mg/kg), administered 2-3 divided doses, there were no effects on blood pressure or heart rate. In this sample, low doses of venlafaxine appeared to be effective in reducing behavioral but not cognitive symptoms of ADHD in 7 of 16 children and adolescents (44%), and adverse effects were not tolerable in 4 of 16 patients (25%). These preliminary results suggest that venlafaxine may aggravate symptoms of hyperactivity, consistent with the behavioral activation reported with fluoxetine and sertraline in children.

The AKR thymoma BW5147 is able to produce lymphokines when stimulated with calcium ionophore and phorbol ester.

We produced the T cell hybridoma D9C1.12.17 by fusing an IL-4-producing T cell clone D9.1Hi with the AKR thymoma BW5147. The resulting hybridoma produced IL-2 as well as IL-4 even though none of the parental cells produced IL-2 after stimulation with Con A. The production of IL-2 was confirmed at the mRNA level by using an S1 nuclease protection assay. Further analysis indicated that Con A-induced IL-2 production was a common phenomenon among T cell hybridomas derived from this fusion. Although BW5147 does not produce detectable lymphokines after Con A stimulation, this line was able to produce IL-2, granulocyte-macrophage colony stimulating factor, and small amounts of IL-3 and IFN-gamma when stimulated with calcium ionophore and phorbol ester. The latter agents are thought to mimic the activating signal(s) delivered through the Ag:MHC TCR. This observation indicates that BW5147 has the ability to produce lymphokines but may lack component(s) which couple the extracellular signal to lymphokine production, and suggests that in T cell hybridomas, part of the spectrum of lymphokines produced may be contributed by BW5147.

Isolation of cDNA for a human granulocyte-macrophage colony-stimulating factor by functional expression in mammalian cells.

A cDNA sequence coding for a human granulocyte-macrophage colony-stimulating factor has been isolated from cDNA libraries prepared from mRNA derived from concanavalin A-activated human T-cell clones. The libraries constructed in the pcD vector system were screened by transfecting COS-7 monkey cells with DNA pools to express the products encoded by full-length cDNA inserts. By assaying the cell supernatants, we identified clones encoding a factor that stimulates the formation of granulocyte and macrophage colonies from human progenitor cells. These results demonstrate that identification of full-length cDNAs for many colony-stimulating factors may be achieved entirely on the basis of detecting the functional polypeptide produced in mammalian cells.

A three-dimensional vision by off-shelf system with multi-cameras.

A three-dimnensional vision system for on-line operation that aids a collision avoidance system for an industrial robot is developed. Because of the real-time requirement, the process that locates and describes the obstacles must be fast. To satisfy the safety requirement, the obstacle model should always contain the physical obstacle entirely. This condition leads to the bounding box description of the obstacle, which is simple for the computer to process. The image processing is performed by a Machine Intelligence Corporation VS-100 machine vision system. The control and object perception is performed by the developed software on a host Digital Equipment Corporation VAX 11/780 Computer. The resultant system outputs a file of the locations and bounding descriptions for each object found. When the system is properly calibrated, the bounding descriptions always completely envelop the obstacle. The response time is data-dependent. When using two cameras and processed on UNIX time sharing mode, the average response time will be less than 2 s if eight or fewer objects are present. When using all three cameras, the average response time will be less than 4 s if eight or fewer objects are present.

Functional analysis of the steroid hormone control region of mouse mammary tumor virus.

Gene fusions between the mouse mammary tumor virus long terminal repeat and the E. coli lacZ gene have been shown to exhibit hormone dependent expression of beta-galactosidase activity. These constructions were used in transient expression experiments to assess the effects of specific modifications introduced into the region upstream of the transcription initiation site. 5' deletions demonstrate that sequences sufficient for wild-type promoter function are contained downstream of residue -64 relative to the initiation site. Other deletions define a region of approximately 80 base pairs between -220 and -140 which contains sequences essential for hormonal control. Between this control region and the promoter lie sequences dispensable for both functions.

The genome of B. subtilis phage SSP1: the topology of DNA molecules.

DNA molecules of B. subtilis phage SPP1 exhibit terminal redundancy and are partially circularly permuted. This was established by the hybridization of selected EcoRI restriction fragments to single strands of SPP1 DNA and by an analysis of the distribution of denaturation loops in partially denatured SPP1 DNA molecules. Deletions in SSP1 DNA are not compensated by an increase in terminally repetitious DNA. This finding, which is unique to SPP1, is discussed in terms of a modification of the Streisinger/Botstein model of phage maturation.

The genome of Bacillus subtilis phage SPP1: the arrangement of restriction endonuclease generated fragments.

SPP1 DNA was cleaved by the restriction endonucleases, BglI, BglII, EcoRI, KpnI, SmaI, and SalI. The molecular weights of the DNA fragments obtained by single enzyme digestion or by consecutive digestion with two enzymes were determined by electron microscopic measurements of contour length and by gel electrophoresis. The major fragments from the six digests could be ordered to give a consistent restriction map of SPP1. The electropherograms of several digests indicated that certain fragments occurred in less than stoichiometric amounts or were heterogeneous in size. Such bands carried a major part of radioactivity, when SPP1 DNA was terminally labelled with P32 prior to degradation by restriction enzymes. These results, and studies of the effect of exonuclease III treatment on restriction enzyme patterns define the terminal restriction fragments. All data obtained support the conclusion drawn in the preceding paper (Morelli et al., 1978 b) that the SPP1 genome is terminally redundant and partially circularly permuted.