Electronic signature of computerized patient records.

The article describes the computerized system developed and used at the Ohio State University Medical Center in Columbus, Ohio to affix a physician's signature electronically. The system electronically sends dictated reports (e.g., discharge summaries, history and physical examinations, and operative reports) and attestation statements to the physician for review. The physician selects the report individually and may approve or enter comments. Comments are forwarded electronically to medical information management. The article describes the fiscal intermediary's requirements and approval process and the impact on delinquent records and accounts awaiting attestation signature before billing.

Implementing a clinical information system.

The design of CIS utilizing the hospital's network allows for the flexibility of providing clinicians with on-line access to additional valuable patient information. The acceptance of CIS and the continuing demand for access to CIS are excellent indicators that development of this system was well worth the efforts of the individuals and teams involved in the planning, design, and implementation of CIS. Although it cannot replace the traditional paper medical record, CIS certainly is being recognized as a timely and reliable resource for the communication of patient information in the Ohio State University's numerous patient treatment facilities.

Optimization of the absorbed power distribution for an annular phased array hyperthermia system.

One of the systems under investigation for producing hyperthermia noninvasively for treating deep-seated tumors is the annular phased array. This device consists of two rings of eight electromagnetic apertures that are placed concentrically about the long axis of the patient and radiate energy toward the center. Previous theoretical and clinical studies have concentrated primarily on systems where the amplitude and phase of the signal applied to each aperture were the same, and these studies have shown that the system is capable of depositing power deep within the patient. Nevertheless, in many situations the system was not capable of producing desirable temperature distributions in the tumor and normal tissue. In this paper we report on a 2-dimensional theoretical investigation where an optimization routine was used to select the amplitude and phases of each of eight apertures. The optimization procedure and resulting calculations were based on CT scans of patients with tumors. The electrical and thermal properties of the different organs and tissues were taken into account. The optimization routine tried to achieve uniform absorbed power in the tumor region with zero absorbed power outside. Using the optimized amplitudes and phases, the SAR (specific absorption rate, W/kg) was calculated for the array. The results show that in general the optimization procedure was successful in that the power deposited within the tumor volume was increased with less power deposited into normal tissue when compared to the equal amplitude and phase case. This SAR data was then used as the input to a program based on the bioheat transfer equation, which calculated the temperature distribution in the patient model for an assumed set of blood perfusion rates. Depending on the location, size of the tumor, and blood perfusion rates, the improvement in the percentage of the tumor brought to therapeutic temperature varied from 0% to as much as 80%.

Differences in the solution structures of oxidized and reduced cytochrome c measured by small-angle X-ray scattering.

While X-ray crystallographic data on cytochrome c show the reduced and oxidized forms to have very similar structures, there is a considerable body of data, mostly from solution studies, that indicates the reduced form is more stable and that the interior of the protein is less accessible to solvent in this state. These observations have led to the hypothesis that while the time-averaged structure is preserved between the two forms, the dynamics of the two forms are different. The oxidized form has been proposed to undergo more large-amplitude, low-frequency motions than the reduced form. The crystal structure data were derived from crystals grown in high salt concentrations, but the solution studies were done at relatively low ionic strength. Small-angle X-ray scattering has been used to examine the effects of the ionic strength and oxidation state on the solution structure of cytochrome c. We find that the radius of gyration and the maximum linear dimension of oxidized cytochrome c are significantly larger than those for reduced cytochrome c, in 5 mM phosphate buffer at pH 7.3, and further that this difference is suppressed by addition of 200 mM sodium chloride. We conclude that there is a real structural difference between the two forms at low ionic strength in solution and that this difference is likely to contribute to the observed differences in accessibility and compressibility.