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Oral diagnostic reporting and synchronized image filing using magneto-optical disks.

An experimental radiologic reporting system has been developed and tested. The rewritable and compact magneto-optical disk (MOD) is applied to storing medical images with oral diagnostic reports of these radiologic images. The disk is 5.25 inches in diameter, has 600 MB memory capacity, is erasable, light and compact. Advantages are simultaneous recording of radiologic images and their oral reports by radiologists, and application to circulation of media inside the hospital as well as to filing of medical images. The MOD has a multimedia function of communication and filing. When medical images are taken and stored, oral interpretation by radiologists can be simultaneously added. Physicians can get information of the images and their reports by oral speech at the same time in front of computer workstation. Furthermore, integration of a voice recognition capability is now being undertaken.

Image Processing, Computer-Assisted

[Magneto-optical disk filing system for oral diagnostic reports and their synchronized images].

The rewritable and compact media of magneto-optical disk (MOD) is firstly applied to store medical images with spoken reporting. The MOD has multi-media function of communication and filing. Our system is optimized in terms of recording length of speech based upon our clinical research. The results will have influences over the future PACS. One of their examples is possibility of multimedia PACS with images, speeches and demographic data. Another example is prevention of dispersion of images which have no interpretations by radiologists. Our next step is to recognize filed speech in background processing for printing reports.

Optical Storage Devices

Infrared imaging of pharmaceutical materials undergoing compaction.

The goal of this study was to use infrared thermography as a new technique to investigate the heat released during compaction and consolidation of pharmaceutical powders and granules. Real-time temperature measurements without physical contact with tablets were provided by a highly sensitive (+/- 0.1 degrees C at 30 degrees C) infrared camera (Agema Infrared Systems, Model 470 with CM-SOFT software). High-resolution images were captured at the takeoff point, i.e., less than 1 sec after compaction, stored on floppy disks, and then analyzed on a regular PC equipped with a VGA color monitor. Thermal surface profiles of tablets were obtained with high geometric and temperature resolution. Reproducibility of the camera readouts was better than 3%. The model granulation used was a direct compression blend of microcrystalline cellulose, spray-dried lactose, and magnesium stearate. This blend was compressed using an instrumented Korsch PH106 rotary press fitted with 1 station of 19.1 x 7.9-mm (0.750 x 0.312-in.) capsule-shaped tools. The effects of compaction force (6-20 kN), rate (130- to 360-msec contact time), and lubricant level (0.5 and 1.0%) on postcompaction temperature rise, caused by heat released during compaction, were investigated. The presence and location of nonhomogeneous heat distribution were assessed as well. Results have shown that the heat released during compaction increases with compaction force. Tablet surface temperatures of 33.8 +/- 0.7 degrees C were observed at 20 kN compaction force in contrast to 29.5 +/- 0.3 degrees C at 6.7 kN.(ABSTRACT TRUNCATED AT 250 WORDS)

Infrared Rays

[Compact form of DNA in solution. XII. Double-stranded polyribonucleotide compacting in the presence of polyethylene glycol].

Double-stranded polyribonucleotides (a replicative form of phage f2 RNA--dsRNA and poly(A) poly(U), can adopt a compact from in solutions, containing NaCl and poly(ethylene glycol) (PEG). According to electron-microscopic observations dsRNA compact particles have the form of disks or doughnuts 200--400 A in diameter. X-ray diffraction patterns from dense slurries of dsRNA compact particles show a reflection at a spacing of 35 A, which is indicative of the existance of ordered regions in compact particles. The intense positive CD band, which is characteristic of dsRNA and poly(A) poly(U) compact particles, presumably results from the ordered regions in the particles. Heating of the solution leads to the disappearance of the intense positive CD band, probably as a result of the destruction of the ordered structure of compact particles. Heat or acid denatured dsRNA molecules as well as single-stranded molecules of ribosomal RNA also form large particles in PEG-containing solutions. However, X-ray diffraction patterns from these particles do not show the 35 A reflection and the specific positive band is not present in their CD spectra, which indicates that such particles lack ordered internal structure. It is suggested that similar mechanism of compactization of double-stranded polynucleotides (DNA and RNA) exist, and compact particles may be divided into two families (psi+ and psi-), differing by the secondary structure of double-stranded polynucleotides, which form the particles.

Bacteriophages

[Changes in the temporomandibular joint under the action on the mandible of distally directed extraoral traction].

Micro- and macroscopic changes in the tissues of the articular fossa vault and the intraarticular disk were examined in puppy experiments. The most marked of these changes were thinning of the compact plate adjacent to the articular surface, active osteoclastic resorption of the bone tissue and marked vascular reaction in the depth of the temporal bone, deformation on the posterior clivus of the articular fossa, destruction of the retroarticular process. Changes in the compact plate facing the brain cavity are negligible and are detectable only by microscopy. The studies have revealed thinning of the intraarticular disk in its middle section. An increased count of dilated vessels, foci of lymphocytic infiltration, and impaired orientation of the bundles of connective tissue fibers were detected in the thickness of the disk.

Animals

Fine structure of the dorsal lingual epithelium of the frog, Rana rugosa.

Scanning and transmission electron microscopy was employed to investigate the ultrastructure of the lingual dorsal epithelial cells of the frog, Rana rugosa. The specimens for scanning electron microscopy were prepared by a method that involved osmium postfixation and treatment with acid to remove extracellular material that adhered to the surface of the tongue. Over almost the entire dorsal surface, filiform papillae, consisting of a large number of non-ciliated cells with microridges and a very small number of ciliated cells, were compactly distributed. Fungiform papillae were scattered among these filiform papillae. A round sensory disk was located on the top of each fungiform papilla. Each sensory disk was encircled by a band of ciliated cells. Transmission electron microscopy revealed that a large part of the filiform papillar epithelium was composed of cells that contained numerous electron-dense granules. These cells were coincident with the non-ciliated cells observed by scanning electron microscopy. In these cells, the nucleus was located on the basal side, and the ergastoplasm was well-developed on the basal side of the nucleus.

Animals

The localization of (3H) thymidine incorporation in the DNA of replicating spinach chloroplasts by electron-microscope autoradiography.

Electron-microscope autoradiography has been used to obtain information on the localization of DNA labelled with [3H]thymidine in chloroplasts known to be replicating and concomitantly synthesizing and segregating DNA, in cultured leaf disks. The studies were made using both Microdol-X developer and a 'compact' developer which gave a smaller grain size. About 80% of the grains were associated with the granal membranes and with presumptive DNA regions (3-nm fibril material in clear areas). Few grains occurred in association with the chloroplast envelope. We suggest that the DNA of chloroplasts is associated with the grana lamellae and extends into the stroma. Some light-microscope autoradiographs of whole chloroplasts show spiral or helical-like labelling patterns. We interpret these patterns as demonstration of the possibility that DNA occurs along the length of a continuous lamellar membrane system. Chloroplast fractionation experiments provided data consistent with the electron-microscope autoradiographic studies as most of the label was associated with chlorophyll-containing lamellae. We consider an association of chloroplast DNA molecules along the length of a continuous lamellar system would ensure an orderly segregation of DNA to daughter chloroplasts, during the binary fission of spinach chloroplasts by constriction division.

Autoradiography

Arrangement of filaments and cross-links in the bee flight muscle Z disk by image analysis of oblique sections.

Information from oblique thin sections and from three-dimensional reconstructions of tilted, transverse thin sections (Cheng, N., and J. F. Deatherage. 1989. J. Cell Biol. 108:1761-1774) has been combined to determine the three-dimensional structure of the honeybee flight muscle Z disk at 70-A resolution. The overall symmetry and structure of the Z disk and its relationship to the rest of the myofibril have been determined by tracing filaments and connecting elements on electron images of oblique sections which have been enhanced by a local crystallographic averaging technique. In the three-dimensional structure, the connecting density between actin filaments can be described as five compact, crystallographically nonequivalent domains. Features C1 and C2 are located on the transverse twofold rotation axes in the central plane of the Z disk. They are associated with the sides of actin filaments of opposite polarity. Features C3, C4, and C5 are present in two symmetry-related sets which are located on opposite sides of the central plane. C3 and C5 are each associated with two filaments of opposite polarity, interacting with the side of one filament and the end of the other filament. C3 and C5 may be involved in stabilizing actin filament ends inside the Z disk. The location of the threefold symmetric connection C4, relative to the thick filament of the adjacent sarcomere, is determined and its possible relationship to the C filament is considered.

Actin Cytoskeleton

An investigation of some factors influencing plug formation and fill weight in a dosing disk-type automatic capsule-filling machine.

The progressive formation of plugs resulting from successive tamps in a dosing disk-type automatic capsule-filling machine was investigated for three fillers: anhydrous lactose, dicalcium phosphate, and microcrystalline cellulose. An evaluation of seven compaction parameters revealed that all tamping stations and all piston positions within a station, with the exception of station #1, contribute equally to plug formation. Model calculations suggesting that fill weight could be achieved in only three tamps were supported by direct experimental observation. The effective available fill volume was shown to be greater than the nominal volume of the dosing disk cavity. This was verified by using a modified scrape-off at station #5, which eliminated the powder head over the disk at that station. Here, increases in tamping force resulted in harder plugs, as measured with an improved plug mechanical strength tester, with fill weights remaining unchanged. However, plug segments did not increase in mechanical strength when additional segments were compressed over them using the same force. For one excipient (microcrystalline cellulose), the fill weights and the mechanical strengths of systems containing 0, 0.10, 0.25, and 0.50% magnesium stearate were measured. The 0.10% level was found to be optimum in that it resulted in maximum plug mechanical strengths and fill weights, regardless of the number of tamps used and/or their intensity.

Capsules

A multicenter evaluation of lipid profiling with a compact analyzer (Miles Clinistat).

We evaluated the Clinistat Analyzer (Miles Inc., Diagnostics Division, Elkhart, IN) for measuring cholesterol, triglycerides, and high-density lipoprotein (HDL) cholesterol at three medical centers. The system, based on multilayer film technology, uses precalibrated, dry film reagent disks. Ten microliters of serum is applied to the dry film reagent disk in the test procedure. For HDL-cholesterol measurement, serum is pretreated by precipitation with phosphotungstic acid and magnesium chloride. Total precision (CVs) of each of the three assays was less than or equal to 5%. The assay ranges were linear and satisfactory for clinical use. Patients' results compared well with established methods. No significant interferences were found with hemolysis, icterus, and lipemia.

Chemistry, Clinical

Human plasma fibronectin structure probed by steady-state fluorescence polarization: evidence for a rigid oblate structure.

In order to more clearly define the structure of human plasma fibronectin (PFn) under physiologic buffer conditions, we determined the mean harmonic rotational relaxation times (rho H) of PFn and the thrombin-derived 190/170-kDa PFn fragment using steady-state fluorescence polarization. These measurements utilized the long lifetime emission (tau = 1.2 X 10(-7) S) exhibited by 1-pyrenebutyrate, which had been covalently attached to amino groups at random sites on the PFn subunit. Our data analysis assumed that two independent processes depolarize the fluorescence exhibited by the dansylcadaverine and 1-pyrenebutyrate conjugates of PFn: (A) rapid (rho H less than 10(-9) S) "thermally-activated" localized rotational motion of the protein side chains bearing the fluorescent probe [Weber, G. (1952) Biochem. J. 51, 145-154] and (B) slow (rho H approximately 10(-6) S) temperature-independent global rotational motion of the whole PFn molecule. Since only the rho H associated with the latter process is a true hydrodynamic parameter (i.e., sensitive to size and/or shape of the PFn molecule), we utilized isothermal polarization measurements to discriminate against the interfering signal arising from "thermally activated" probe rotation. The rho H (4.4 +/- 0.9 microseconds) derived from an experiment in which pyrene-PFn fluorescence polarization was monitored as a function of sucrose concentration at constant temperature is 7 (+/- 1.4) times longer than that predicted for an equivalent hydrated sphere. We propose that "thermally activated" probe rotation gives rise to the nearly 100-fold shorter PFn rho H values previously reported in the literature. Consequently, our data exclude all previous models which invoke segmental flexibility of the PFn peptide backbone. The simplest hydrodynamic model supported by our fluorescence data is an oblate ellipsoid with an axial ratio of 15:1. All prolate models can be unambiguously excluded by this result. We estimate that the disk-shaped PFn molecule has a diameter and thickness of 30 and 2 nm, respectively. Electron microscopy of negatively stained PFn specimens on carbon also showed PFn to have a compact rounded structure. The much faster rotational relaxation rate of the pyrene-190/170-kDa PFn fragment (rho H = 0.92 +/- 0.11 microseconds) compared to pyrene-PFn indicated that this monomeric PFn fragment, like native PFn, had an oblate shape under physiologic buffer conditions.

Chromatography, Affinity

[The qualitative and quantitative diagnostic significance of P-VEP in the evaluation of glaucomatous visual function damage].

The pattern visual evoked potential (P-VEP) and the central visual field in 63 cases (95 eyes) of primary glaucoma were simultaneously measured with the American Compact Four electrophysiology apparatus and the Chinese TBC-IA central field analyzer. The data showed that the mean latency of P1 in the glaucomatous eyes was significantly lengthened, and this occurred before the visual field and disk abnormalities, indicating that VEP is sensitive in the detection of early glaucoma. Furthermore, the VEP changes were consistent with the central visual field defects qualitatively and quantitatively. Therefore, the latency of P1 can be a useful quantitative index in the evaluation of glaucomatous visual function damage. The difference in diagnostic sensitivity to glaucoma between VEP and visual field changes were discussed. The authors suggest that combination of the two may be a more useful index.

Adult

Synchronous bilateral fluorescein angiography. A new technique.

Simultaneous angiography of both eyes allows the synchronous measurement of the arm-retina-time and the retinal circulation time in each eye. The dye-filling pattern of retinal arteries, choroid, disc, and cilioretinal vessels can be compared. A new method of simultaneous fluorescein angiography of both eyes, using two fundus cameras, is demonstrated. Each camera is operated by a separate power unit, thereby providing sufficient light energy for one picture every 0.6 second. The fluorescein is injected by means of an automatic injector in order to create a compact dye bolus. Simultaneous angiograms of a healthy patient and of a patient with unilateral carotid occlusion are shown.

Choroid

Microtubule organization during maturation of Xenopus oocytes: assembly and rotation of the meiotic spindles.

Assembly of the meiotic spindles during progesterone-induced maturation of Xenopus oocytes was examined by confocal fluorescence microscopy using anti-tubulin antibodies and by time-lapse confocal microscopy of living oocytes microinjected with fluorescent tubulin. Assembly of a transient microtubule array from a disk-shaped MTOC was observed soon after germinal vesicle breakdown. This MTOC-TMA complex rapidly migrated toward the animal pole, in association with the condensing meiotic chromosomes. Four common stages were observed during the assembly of both M1 and M2 spindles: (1) formation of a compact aggregate of microtubules and chromosomes; (2) reorganization of this aggregate resulting in formation of a short bipolar spindle; (3) an anaphase-B-like elongation of the prometaphase spindle, transversely oriented with respect to the oocyte A-V axis; and (4) rotation of the spindle into alignment with the oocyte axis. The rate of spindle elongation observed in M1 (0.7 microns min-1) was slower than that observed in M2 (1.8 microns min-1). Examination of spindles by immunofluorescence with antitubulin revealed numerous interdigitating microtubules, suggesting that prometaphase elongation of meiotic spindles in Xenopus oocytes results from active sliding of antiparallel microtubules. A substantial number of maturing oocytes formed monopolar microtubule asters during M1, nucleated by hollow spherical MTOCs. These monasters were subsequently observed to develop into bipolar M1 spindles and proceed through meiosis. The results presented define a complex pathway for assembly and rotation of the meiotic spindles during maturation of Xenopus oocytes.

Animals

Access to information about AIDS.

Medical information related to human immunodeficiency virus (HIV) infection is highly diverse, and the practicing physician or researcher may find specific information difficult to locate. To provide timely access to medical information on topics related to the acquired immunodeficiency syndrome (AIDS), several computer-based products have recently been developed. Some are available from vendors of online information systems, whereas others are available only on CD-ROM or floppy disk. We review several computer-based products. AIDSLINE is the most comprehensive bibliographic index, AIDSTRIALS contains specific information about ongoing unpublished investigational studies, and AIDS Knowledge Base from San Francisco General Hospital is an up-to-date electronic textbook covering all aspects of AIDS. COMPACT LIBRARY: AIDS operates on a microcomputer and combines several databases, including full-text AIDS-related articles from nine major medical journals. AIDS References from the Bureau of Hygiene and Tropical Diseases provides critical analysis of publications worldwide. Although smaller in size than AIDSLINE, about one third of the publications covered by this resource are not covered by AIDSLINE.

Acquired Immunodeficiency Syndrome

The Erlangen micro-lightguide spectrophotometer EMPHO I.

The Erlangen micro-lightguide spectrophotometer EMPHO 1 was designed for fast diffuse reflection (remission) spectrophotometry in small tissue volumes. The aim was to construct a compact, modular instrument with a high repetition rate which can be adapted to moving organs, e.g. the beating heart in situ, by the use of highly flexible micro-lightguides. Focusing problems, which cannot be solved when conventional optical devices such as microscopes are used in moving tissues, become negligible. A bandpass interference filter disk, which is rotated by a motor serves as a monochromating unit. One diffuse reflection spectrum in a selected wavelength domain is recorded during each revolution of the motor. Special filter disks, with spectral ranges of 400-520, 500-630, 600-1200 nm can be used for different tasks. The monochromated light is transmitted by means of a flexible fluid-lightguide to a photomultiplier tube. The electrical signal, which is proportional to the light intensity is recorded by an IBM-compatible AT. An analogue to digital converter has been developed for the AD conversion. Sampling of the spectra occurs in steps of 2 nm triggered by a decoding unit, containing an EPROM where the function between the wavelength-angular position characteristic of the filter disk is stored. A decoder wheel mounted on the same axle as the driving motor is used to program the decoder unit and to recall the wavelength position function. The decoding procedure enables a high wavelength reproducibility to be attained. The monochromating device allows a sampling velocity of 100 spectra per second. The EMPHO I has been successfully applied to experiments in the beating heart, the brain, the eye, the liver, the small intestine and the skeletal muscle of mammals. First investigations have also been performed in the heart during open heart surgery and in human skin. The apparatus has a high sampling rate and the small catchment volume allows measurements of remission spectra in tissue volumes supplied by only a few capillaries. The absolute oxygenation and the relative haemoglobin concentration can be determined by on-line computer evaluation of the recorded spectra and displayed on a screen.

Animals

[Personal laboratory data management system using optical card].

This paper describes the development and state of the medical optical card system. Recently, computerized medical information systems have been developed in many hospitals and they allow quick access and automatic processing of the patient's data in medical practice and research. However, the use of the information stored by such a system has been limited to each hospital while it is not rare for a patient to change hospitals. It is desirable to develop a personal medical data management system which allows the patient to carry his own medical records for a long period of time, and hospitals to share the information about the patient. The optical card is a transportable information medium with a large capacity. Since data are recorded optically with a laser beam, the card is tolerant to environmental factors such as static electricity, magnetism and impact which injure other transportable media such as IC card, magnetic stripe card and floppy disk. Therefore, the optical card suits our purpose. We developed a prototype of the medical optical card system. In our system, the card can contain character data, numerical data, two-valued image data and electrocardiographical data. In order to share laboratory data among different database systems, we defined a data descriptive language which enables complete and compact data description without any external code tables. The recorded patient data are presented in the original multi-window system, which allows the doctor to see any combination of any part of the patient's information simultaneously.

Clinical Laboratory Information Systems