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PubMed2005

Standardized exchange of medical data between a research database, an electronic patient record and an electronic health record using CDA/SCIPHOX.

The exchange of medical data from research and clinical routine across institution borders in a structured way, based on national and international standards, is essential to build an integrated and connected health platform. In this project we developed a HL7 CDA/SCIPHOX based integration platform to exchange data between a research database, an electronic health record and an electronic patient record (Soarian).

Biomedical Research↗
PubMed1990

Electron microscopy, immune electron microscopy, enzyme immunoassay and immunofluorescent evaluation of rotaviruses isolated from individual calves and piglets.

Rotaviruses were isolated in primary bovine foetal kidney cells from 3 of 13 (23.1%) tested suckling calves and from 3 of 14 (21.4%) suckling piglets both suffering of acute diarrhoea, as confirmed by serological tests. The presence of rotaviral antigen in culture supernatant was revealed by double sandwich enzyme immunoassay (EIA) and direct immunofluorescence (IF). Transmission electron microscopy (TEM) and immune electron microscopy (IEM) showed particles with an average diameter of 70 nm. The strains adapted to continuous pig kidney cells PK-15 have lost their reactivity in EIA, although TEM revealed the presence of rotavirions.

Animals↗
PubMed1984

Electronic document delivery: directing interlibrary loan traffic through multiple electronic networks.

The University of Nebraska Medical Center (UNMC) uses five different electronic networks for interlibrary loan (ILL) request transmission. The advantages and problems of using electronic networks for ILL request transmission are discussed. Advantages include speed of request transmission, improved capabilities for locating documents, lower labor costs, improved turnaround time, and production of user reports and statistics. Disadvantages include increased work load, additional staff training, coordination of non-standard networks, determining access protocols, and establishing priorities for handling requests.

Interlibrary Loans↗
PubMed1996

Interaction of electron leak and proton leak in respiratory chain of mitochondria--proton leak induced by superoxide from an electron leak pathway of univalent reduction of oxygen.

By incubating the isolated rat myocardial mitochondria with xanthine-xanthine oxidase, an exogenous superoxide (O2.-) generating system, and by ischemia-reperfusion procedure of isolated rat heart as an endogenous O2.- generating system, it was found that both sources O2.- showed the same injurious effects on mitochondrial function resulting in (i) increasing proton leak rate, lowering proton pumping activity and H+/2e ratio of respiratory chain, and (ii) decreasing transmembrane potential of energized mitochondrial inner membrane by succinate oxidation. The injurious effects of O2.- on these mitochondrial bioenergitical parameters mentioned above exhibited a dosage- or reaction time-dependent mode. O2.- has no effects on the electron transfer activity and transmembrane potential of nonenergized mitochondria. Being a superoxide scavenger, 3,4-dihydroxylphenyl lactate showed obvious protection effects against damage of both exogenous superoxide sources from xanthine-xanthine oxidase system and endogenous O2.- source from ischemia-reperfused heart on proton pumping activity, H+/2e ratio and transmembrane potential of energized mitochondria. The experimental results presented here clearly showed that O2.- radicals induce an increase of proton leak in mitochondria directly related to the molecular mechanism of early phase damage of ischemia-reperfused heart, and also provide evidence to support our recent proposed hypothesis that electron leakage to oxygen to form O2.- in respiratory chain is one of the mechanical cause of proton leakage in mitochondria.

Animals↗
PubMed1993

Dendritic cell/lymphocyte clustering: morphologic analysis by transmission electron microscopy and distribution of gold-labeled MHC class II antigens by high-resolution scanning electron microscopy.

Dendritic cells (DCs) are potent antigen-presenting cells for a variety of immune responses; however, their mechanism of action has not been established. It is known that DCs can cluster with one another and with other cell types during in vitro immune responses, and clustering may be essential for the activation of resting lymphocytes. In this study, ultrastructural examination of clusters that form during extended culture of enriched rat splenic DCs (approximately 70% DCs) is reported. DCs were readily distinguished from other cell types, which included lymphocytes and macrophages. DCs displayed characteristic veils and/or dendritic processes that intertwined with processes of other cells within the cluster, or extended from the cluster periphery. Occasional DCs contained large vacuoles lined with small vesicles. A paramount feature of DCs is their constitutive expression of high levels of surface major histocompatibility complex class II antigens. The surface distribution of class II antigens on clustering DCs was examined using 10 nm immunogold labeling techniques and high-resolution scanning electron microscopy. DCs were readily distinguished by morphologic criteria, and examination of various surface membrane regions revealed a differential distribution of class II antigens. Gold label was frequently distributed in linear arrays and clusters, suggesting a cytoskeletal role in the recycling/redistribution of Class II antigens. These morphologic findings further an understanding of basic DC biology and their mechanism of action as antigen-presenting cells.

Animals↗
PubMed2004

Comparison of environmental scanning electron microscopy with high vacuum scanning electron microscopy as applied to the assessment of cell morphology.

The efficacy of conventional high vacuum scanning electron microscopy (SEM), environmental SEM (ESEM), and confocal laser scanning microscopy techniques in the assessment of cell-material interactions is compared. Specific attention is given to the application of these techniques in the assessment of the early morphological response of human osteoblast-like cells cultured on titanium dioxide. The processing of cells cultured for conventional high vacuum SEM leads to the loss of morphological features that are retained when using ESEM. The use of cytoskeletal labeling, viewed with confocal laser scanning microscopy, in conjunction with ESEM gives an indication of the changes to cell morphology as a consequence of incubation time in response to interactions at the biological/material interface.

Actins↗
PubMed1988

Introduction to the computer image processing of electron micrographs of two-dimensionally ordered biological structures.

Methods are described for the analysis of electron micrographs of regular biological objects. Fourier-based processing of one-dimensionally ordered arrays is described by way of introduction, before analysing two-dimensional crystals in projection with the aim of enhancing signal:noise ratio and thus of feint features that were initially obscured. This form of analysis is then extended to decomposing the moiré patterns formed when sheets overlap, thereby enabling the separation of interfering image patterns. Analogous forms of an analysis can also be applied to objects with rotational symmetry. Methods for treating the effect of the microscope imaging system and compensating for lattice disorder in crystalline specimens are also discussed.

Fourier Analysis↗
PubMed1992

Bloch wave treatment of symmetry and multiple beam cases in reflection high energy electron diffraction and reflection electron microscopy.

Bloch wave equations for the multiple beam cases in reflection high energy electron diffraction (RHEED) are derived from the integral equation by forward- and back-scattering Green function operators. A linearization is achieved through separation in a forward- and a back-scattering component for each beam. This leads to a set of fundamental equations similar to the transmission case, but with a non-Hermitian matrix, and the beams may be entered as either forward-, back-scattered, or both. The number of beams needed to be included in RHEED calculations is thus reduced, and so are the computing time and computer space required. The systematic row case, corresponding to reflections from planes parallel to the crystal surface, is treated in detail and illustrated by calculations of dispersion surfaces and rocking curves for Au(001). Symmetry relations for the systematic row and between reciprocal rows are discussed and illustrated.

Crystallography↗
PubMed1993

Comparison of bacteriorhodopsin/phospholipid interactions in DMPC and DMPG bilayers: an electron spin resonance spectroscopy and freeze-fracture electron microscopy study.

Bacteriorhodopsin (BR), separated from the Halobacterium halobium purple membrane (PM) lipids, broadened the main gel-fluid phase transition (Tc) of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) bilayers and 1,2-dimyristoyl-sn-glycero-3-phosphoryl-3'-rac-glycerol (DMPG) bilayers to similar degrees compared to the respective protein-free bilayers. Analysis of two component ESR spectra from spin-labelled phospholipids suggested that, at temperatures above Tc, each 26 kDa BR was associated with 18-21 boundary lipids in both DMPC and DMPG bilayers. This was consistent with the random dispersive properties of the BR particles observed by freeze-fracture electron microscopy in DMPG and DMPC bilayer complexes when quenched from temperatures above Tc. DMPG, as shown for DMPC in other studies, did not aggregate BR into the 2D-hexagonal arrays of PM at temperatures below Tc. Despite the presence of positively-charged amino acid residues which project from the BR into the polar headgroup region of the phospholipid bilayer, BR exhibited a lower affinity for the negatively-charged phosphoglycerol headgroup compared to the zwitterionic phosphocholine headgroup, suggesting that ionic interactions between BR and phospholipid headgroups are not significant and serve a passive function, perhaps facilitating the close packing of BR into 2D-arrays.

Bacteriorhodopsins↗
PubMed1977

Electron microscopy of human melanosomes in unstained, fresh air-dried hair bulbs and their examination by electron probe microanalysis.

Electron microscopy of unstained, fresh air-dried spreads of plucked human hair bulbs revealed relatively well preserved melanocytes and dense storage granules of melanin. Energy dispersive X-ray microanalysis of melanosomes and premelanosomes from black facial hair bulbs disclosed high peaks for potassium and sulfur, intermediate peaks for magnesium and calcium, and low but distinct ones for phosphorus and chlorine. No peaks for magnesium were found in the central portion of mature melanosomes, but at their edges and in premelanosomes conspicuous peaks for this element were obtained.

Electron Probe Microanalysis↗
PubMedDate not supplied

Electron microscopy of isolated human hepatocytes. (Micromethods for scanning and transmission electron microscopy).

We have investigated, by scanning and transmission electron microscopy (SEM and TEM), the cell surface morphology of isolated human hepatocytes. For this purpose, liver cells were mechanically isolated from surgical or needle liver biopsies, fixed in 3% glutaraldehyde and post-fixed in 2% osmium tetroxide. In order to handle a low number of cells, a particular procedure for harvesting hepatocytes on coverslips has been developed for SEM and an in situ embedding procedure in polyethylene-embedding capsules was applied for TEM. A rough membrane exhibiting short, uniform microvilli and pores of 0.1 mu in diameter was the main feature of isolated liver cells. Furthermore, single hepatocytes showed no polarity and junctional or bile canaliculus remnants were rarely observed. However, differences in surface configuration were noted in relation to culture conditions, such as oxygen and temperature during isolation procedures. SEM, when controlled by TEM for intracellular preservation, is proposed as a reliable method for screening small quantities of hepatocyte suspensions, for intact cells and for the study of surface configuration under experimental conditions.

Cells, Cultured↗
PubMed1978

Electron capture at the iron-oxygen centre in single crystals of oxymyoglobin studied by electron spin resonance spectroscopy.

Exposure of single crystals of oxy-myoglobin to 60Co gamma-rays at 77 K results in electron addition to the Fe-O2 units. The resulting ESR spectrum has been analysed to give the principal values and directions for the g-tensor of this unit. The results suggest that the dioxygen ligand is strongly tilted, the direction of tilt being close to one of the bisectors of the N-Fe-N bond angles. Possible reasons for this orientation are discussed.

Chemical Phenomena↗
PubMed1987

Two-electron reduction is required for rapid internal electron transfer in resting, pulsed and oxygenated cytochrome c oxidase.

The resting as well as the 420 nm and 428 nm forms of cytochrome oxidase have been studied in kinetic experiments with an excess of enzyme over reduced cytochrome c. No difference was found in the behavior of the two activated forms. With all three forms, a fraction of cytochrome a was reoxidized with a rate which was much lower than kcat. This suggests that intramolecular transfer to the dioxygen-reducing site occurs only if both cytochrome a and CuA are reduced. An initial rapid phase in the oxidation of cytochrome a in the pulsed and oxygenated enzymes is related to the presence of a three-electron-reduced dioxygen intermediate. The increased catalytic activity of pulsed and oxygenated oxidase can be explained on the basis of a shift in the redox equilibrium between cytochrome a and CuA.

Animals↗
PubMedDate not supplied

Repair of early cholesterol-induced aortic lesions in rabbits after withdrawal from short-term atherogenic diet. Scanning electron-microscopical (SEM) and transmission electron-microscopical (TEM) observations.

Signs of repair of early atherosclerotic lesions after withdrawal of rabbits from a short-term atherogenic diet have been observed by means of scanning and transmission electron microscopy. The endothelial lining was lacking over large portions of the plaques during early atherogenesis. During the regression phase, hematic cholesterol values returned to normal, the smooth muscle cells of the plaques lost a large part of the lipids they had accumulated, while the surface of the plaques was covered by a continuous layer of endothelial cells.

Animals↗
PubMed1983

Localization of gallium in tumor cells. Electron microscopy, electron probe microanalysis and analytical ion microscopy.

The incorporation of gallium in tumor cells in vitro and in solid tumors was studied with electron microscopy and two microanalytical techniques. It was thus possible (1) to directly prove that gallium is concentrated in lysosomes of tumor cells; (2) to demonstrate that in these lysosomes, gallium is precipitated with phosphorus; and (3) to propose a mechanism of gallium concentration in tumor cells; in this mechanism, the accumulation of gallium as phosphate salts in lysosomes is directly related to the acid phosphatase activity of these organelles.

Animals↗
PubMed1976

The use of backscattered electrons for imaging purposes in a scanning electron microscope.

It is shown that the use of a very large detector for backscattered electrons can provide a signal comparable to that obtained in the secondary emission mode and that the resolution available is also comparable. A technique is described whereby the difference is taken between these two signals, and the use of this difference signal can significantly enhance surface details. It is believed that the use of such a signal should ultimately prove advantageous in increasing resolution.

Animals↗
PubMed1985

Scanning electron microscopy, x-ray diffraction, and electron microprobe analysis of calcific deposits on intrauterine contraceptive devices.

Deposits found intrauterine contraceptive devices (IUDs) were studied by scanning electron microscopy, x-ray diffraction, and energy dispersive x-ray microanalysis. All seven devices, including five plastic and two copper IUDs, were coated with a crust containing cellular, acellular, and fibrillar material. The cellular material was composed of erythrocytes, leukocytes, cells of epithelial origin, sperm, and bacteria. Some of the bacteria were filamentous, with acute-angle branching. The fibrillar material appeared to be fibrin. Most of the acellular material was amorphous; calcite was identified by x-ray diffraction, and x-ray microanalysis showed only calcium. Some of the acellular material, particularly that on the IUD side of the crust, was organized in spherulitic crystals and was identified as calcium phosphate by x-ray microanalysis. The crust was joined to the IUD surface by a layer of fibrillar and amorphous material. It is suggested that the initial event in the formation of calcific deposits on IUD surfaces is the deposition of an amorphous and fibrillar layer. Various types of cells present in the endometrial environment adhere to this layer and then calcify. Thus, the deposition of calcific material on the IUDs is a calcification phenomenon, not unlike the formation of plaque on teeth. Hum Pathol 16:732-738, 1985.

Calcium↗