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At least 379 records · Page 21Linked to original sources
PubMed2001

Strain selection of Metarrhizium anisopliae by image analysis of colony morphology for consistency of steroid biotransformation.

Quantitative description of colony morphological images of the fungus Metarrhizium anisopliae was done by means of computer image analysis based on fractal analysis. Compared with simple fractal analysis, the differences in the morphological features of colonies were expressed more accurately by multifractal analysis. The use of multifractal analysis markedly improved the reliability of colony image analysis, which could be extended to morphological characterization for colony recognition and classification. First, the multifractal spectrum was calculated from each morphological image and 14 features were defined on the spectrum to describe the spectral line profile. Second, three features, alpha-right, alpha-width, and f-start, were selected from the 14 features in two-dimensional feature vector spaces and a feature augmented vector (alpha-right, alpha-width, and f-start, 1)(T) was generated and used for classifier design. Third, a statistical least mean square error (LMSE) algorithm was applied to design a piecewise-linear classifier, which consists of two linear classifiers, d(1)(x) and d(2)(x). Representative colony samples were used as training and test sample sets, which were previously classified into a high-activity class and another class by a training person. After passing the training phase, the piecewise-linear classifier could be used for automated classification of unknown colony samples. A correct recognition rate of 96% was achieved in this manner. Compared with conventional strain selection methods, this new method has the advantage of less subjectivity, reduced labor and time, and improved ability to deal with a large number of colonies.

Algorithms↗
PubMed2003

Analysis of the structure of very large bacterial aggregates by small-angle multiple light scattering and confocal image analysis.

This work aims at developing a more accurate measurement of the physical parameters of fractal dimension and the size distribution of large fractal aggregates by small-angle light scattering. The theory of multiple scattering has been of particular interest in the case of fractal aggregates for which Rayleigh theory is no longer valid. The introduction of multiple scattering theory into the interpretation of scattering by large bacterial aggregates has been used to calculate the fractal dimension and size distribution. The fractal dimension is calculated from the form factor F(q) at large scattering angles. At large angles the fractal dimension can also be computed by considering only the influence of the very local environment on the optical contrast around a subunit. The fractal dimensions of E. coli strains flocculated with two different cationic polymers have been computed by two techniques: static light scattering and confocal image analysis. The fractal dimensions calculated with both techniques at different flocculation times are very similar: between 1.90 and 2.19. The comparison between two completely independent techniques confirms the theoretical approach of multiple scattering of large flocs using the Mie theory. Size distributions have been calculated from light-scattering data taking into account the linear independence of the structure factor S(q) relative to each size class and using the fractal dimension measured from F(q) in the large-angle range or from confocal image analysis. The results are very different from calculations made using hard-sphere particle models. The size distribution is displaced toward the larger sizes when multiple scattering is considered. Using this new approach to the analysis of very large fractal aggregates by static light multiple scattering, the fractal dimension and size distribution can be calculated using two independent parts of the scattering curve.

Bacteria↗
PubMed2002

[The applying and foreground of quantifying DNA content by image analysis technique in determining postmortem interval].

Image Analysis Technique(IAT) was developed at 1950's, which quantifies the changing all the part of image by sampling, processing, quantifying, computing, analyzing the information of image. And now it has become a normal quantifying technique in biology and medicine research. In the present paper, we reviewed briefly the principium of quantifying the DNA content by IAT, the law of degradation of DNA in nucleus and the foreground of this method in determining PMI in forensic pathology.

DNA↗
PubMed1998

[Comparison of film-screen combinations in contrast-detail diagram and with interactive image analysis. 3: Trimodal histograms of gray scale distribution in bar groups of lead pattern images].

The following four screen film combinations were compared: a) a combination of anticrossover film and UV-light emitting screens, b) a combination of blue-light emitting screens and film and c) two conventional green fluorescing screen film combinations. Radiographs of a specially designed plexiglass phantom (0.2 x 0.2 x 0.12 m3) with bar patterns of lead and plaster and of air, respectively were obtained using the following parameters: 12 pulse generator, 0.6 mm focus size, 4.7 mm aluminum prefilter, a grid with 40 lines/cm (12:1) and a focus-detector distance of 1.15 m. Image analysis was performed using an Ibas system and a Zeiss Kontron computer. Display conditions were the following: display distance 0.12 m, a vario film objective 35/70 (Zeiss), a video camera tube with a PbO photocathode, 625 lines (Siemens Heimann), an Ibas image matrix of 512 x 512 pixels with a spatial resolution of ca. 7 cycles/mm, the projected matrix area was 5000 micron 2. Maxima in the histograms of a grouped bar pattern were estimated as mean values from the bar and gap regions ("mean value method"). They were used to calculate signal contrast, standard deviations of the means and scatter fraction. Comparing the histograms with respect to spatial resolution and kV setting a clear advantage of the UVR system becomes obvious. The quantitative analysis yielded a maximum spatial resolution of approx. 3 cycles/mm for the UVR system at 60 kV which decreased to half of this value at 117 kV caused by the increasing influence of scattered radiation. A ranking of screen-film systems with respect to image quality and dose requirement is presented. For its evaluation an interactive image analysis using the mean value method was found to be superior to signal/noise ratio measurements and visual analysis in respect to diagnostic relevance and saving of time.

Humans↗
PubMed1999

Determination of the size of a foreign body in the eye using image analysis of its roentgenogram.

The case of a computer-enhanced image analysis of X-ray pictures of a pellet in the orbit of a man who sustained a shotgun injury to his right eyeball is presented. The man was shot accidentally during a pheasant hunt. Two hunters were shooting simultaneously but they were using three different sizes of pellet--3.0, 3.5 and 4.0 mm. One of the pellets hit a third man in the eye. He sustained serious injury with a resultant loss of sight in this eye despite immediate medical treatment. Unfortunately the pellet could not be removed from the orbit, but it was necessary to establish who was responsible for the injury. The problem lay in determining the specification and size of the pellet at that moment. The problem was solved using computer-enhanced video image analysis of the X-ray pictures of the pellets. The image processor LUCIA G (http(/)/www.lim.cz) was used.

Adult↗
PubMedDate not supplied

Applications of computerized microscopic image analysis in infectious diseases.

Advances in computerized microscopy have resulted in image analysis systems that rapidly and precisely measure various aspects of cellular morphology and physiology. These systems-composed of a microscope and attached photomultiplier tube or camera, an image processor, and a computer-have been used to measure lysosomal enzymes, pH, and calcium within phagocytes; to detect viral nucleic acids in in situ hybridization preparations; and to quantitate rates of cellular movement. These experiments have shown that (1) the intracellular proliferation of virulent microorganisms is associated with reductions in acid phosphatase, beta-glucuronidase, and lysozyme activity; (2) virulent Toxoplasma gondii, Legionella pneumophila, and Nocardia asteroides inhibit phagosomal acidification; and (3) changes in intracellular calcium movement affect phagocytic function. These methods have also been used to detect the AIDS virus within cultured lymphocytes and to measure cellular chemotaxis and chemokinesis. Further advances in technology should produce improved microscopic image analysis systems with wider applications for the investigation of infectious diseases.

Antibodies↗
PubMed1992

An image analysis and statistical evaluation program for the assessment of tumour cell invasion in vitro.

Tumour cell invasion is a complex process, which is essential for the formation of metastasis and is therefore of critical clinical importance. For detailed investigations of the invasive process, quantifiable in vitro models of invasion are necessary. In this study we describe an image analysis procedure and a statistical program which facilitate an objective analysis of experiments carried out using the embryonic chick heart invasion model of Mareel. Tumour multicellular spheroids are confronted with embryonic chick heart fragments in culture and are sampled after different time intervals for up to 7 days. Immunohistological sections are then evaluated by an image analysis procedure which provides 9 parameters indicating invasion, proliferation and destruction taking place in the confrontation cultures. The data obtained by image analysis are further evaluated by a statistical program which describes the change with time of each parameter by means of linear regression analysis. Thus the data obtained at various time intervals serve as the source data for a single statistic, namely the slope of the regression line. Confidence intervals and statistical differences between various experiments can be calculated. In order to make the procedure more comprehensible in biological terms, the program provides a full text interpretation of the experimental results. The image analysis procedure in conjunction with statistical evaluation and text interpretation provides a comprehensive tool for the quantitative assessment of experimental invasion in vitro.

Animals↗
PubMed1996

Quantification of Alzheimer-type neurofibrillary lesions by automated image analysis.

Neurofibrillary pathology is seen in a wide variety of disorders such as Alzheimer's disease (AD), progressive supranuclear palsy and the Parkinsonism-dementia amyotrophic lateral sclerosis complex of Guam. To assess the pathological importance of these lesions quantitative studies need to be undertaken. To date, most neuropathological studies have been based on qualitative, or at best semi-quantitative, data reporting the presence or absence of specific lesion types. To obtain such data traditionally involves laborious manual measurements, which rely heavily on the skill of the investigator and tend to have low inter- and intra-rater reliabilities. We have developed a novel analysis technique, using colour image analysis, which can accurately quantify the total amount of neurofibrillary damage present. Furthermore we have developed a set of mathematically defined morphological criteria to allow objective discrimination between the three types of neurofibrillary damage seen in the cortex immunostained with Alz-50. Use of this novel technique provides a reliable, rational means for the classification of neurofibrillary lesions.

Alzheimer Disease↗
PubMed2005

Detection of methyl parathion using immuno-chemiluminescence based image analysis using charge coupled device.

A novel method based on immuno-chemiluminescence and image analysis using charge coupled device (CCD) for the qualitative detection of methyl parathion (MP) with high sensitivity (up to 10 ppt) is described. MP antibodies raised in poultry were used as a biological sensing element for the recognition of MP present in the sample. The immuno-reactor column was prepared by packing in a glass capillary column (150 microl capacity) MP antibodies immobilized on Sepharose CL-4B through periodate oxidation method. Chemiluminescence principle was used for the detection of the pesticide. Light images generated during the chemiluminescence reaction were captured by a CCD camera and further processed for image intensity, which was correlated with pesticide concentrations. K(3)Fe(CN)(6) was used as a light enhancer to obtain detectable light images. Different parameters including concentrations of K(3)Fe(CN)(6), luminol, urea H(2)O(2), antibody, addition sequence of reactants and incubation time to obtain best images were optimized. The results obtained by image analysis method showed very good correlation with that of competitive ELISA for methyl parathion detection. Competitive ELISA method was used as a reference to compare the results obtained by CCD imaging.

Equipment Design↗
PubMed1997

KAMEDIN: a telemedicine system for computer supported cooperative work and remote image analysis in radiology.

The software system KAMEDIN (Kooperatives Arbeiten und MEdizinische Diagnostik auf Innovativen Netzen) is a multimedia telemedicine system for exchange, cooperative diagnostics, and remote analysis of digital medical image data. It provides components for visualisation, processing, and synchronised audio-visual discussion of medical images. Techniques of computer supported cooperative work (CSCW) synchronise user interactions during a teleconference. Visibility of both local and remote cursor on the conference workstations facilitates telepointing and reinforces the conference partner's telepresence. Audio communication during teleconferences is supported by an integrated audio component. Furthermore, brain tissue segmentation with artificial neural networks can be performed on an external supercomputer as a remote image analysis procedure. KAMEDIN is designed as a low cost CSCW tool for ISDN based telecommunication. However it can be used on any TCP/IP supporting network. In a field test, KAMEDIN was installed in 15 clinics and medical departments to validate the systems' usability. The telemedicine system KAMEDIN has been developed, tested, and evaluated within a research project sponsored by German Telekom.

Humans↗
PubMed2003

On-line prediction of yield grade, longissimus muscle area, preliminary yield grade, adjusted preliminary yield grade, and marbling score using the MARC beef carcass image analysis system.

The present experiment was conducted to evaluate the ability of the U.S. Meat Animal Research Center's beef carcass image analysis system to predict calculated yield grade, longissimus muscle area, preliminary yield grade, adjusted preliminary yield grade, and marbling score under commercial beef processing conditions. In two commercial beef-processing facilities, image analysis was conducted on 800 carcasses on the beef-grading chain immediately after the conventional USDA beef quality and yield grades were applied. Carcasses were blocked by plant and observed calculated yield grade. The carcasses were then separated, with 400 carcasses assigned to a calibration data set that was used to develop regression equations, and the remaining 400 carcasses assigned to a prediction data set used to validate the regression equations. Prediction equations, which included image analysis variables and hot carcass weight, accounted for 90, 88, 90, 88, and 76% of the variation in calculated yield grade, longissimus muscle area, preliminary yield grade, adjusted preliminary yield grade, and marbling score, respectively, in the prediction data set. In comparison, the official USDA yield grade as applied by online graders accounted for 73% of the variation in calculated yield grade. The technology described herein could be used by the beef industry to more accurately determine beef yield grades; however, this system does not provide an accurate enough prediction of marbling score to be used without USDA grader interaction for USDA quality grading.

Animals↗
PubMedDate not supplied

Topographic study of sudanophilic lesions in cholesterol-fed minipigs by image analysis.

A new morphometric technique using image analysis has been developed to express the topographic distribution of atherosclerotic lesions in unambiguous statistical terms. Computer-stored images of opened Sudan IV-stained aortas and iliac and coronary arteries from hypercholesterolemic minipigs (n = 39) were used in this study. The image processing methods included transformation of the data to standard templates, automated image segmentation, and creation of probability-of-occurrence maps. These maps have shown that sudanophilic lesions are localized with a characteristic topography along the aortas and iliac and coronary arteries. Areas of high probability are associated with the entrance regions of vessels and the lateral leading edges of the major flow dividers. Regions immediately distal to large branches were found to be areas of low probability. Despite the association of areas of sudanophilia with entrance regions and branch points, a major portion of sudanophilic lesions was not associated with any orifice region (e.g., ductus scar, dorsolateral surface of abdominal aorta, and ventral surface of terminal aorta). The present study provides the necessary information for the development of a rational sampling strategy for the experimental study of the distribution of localizing factors (e.g., hemodynamic, biochemical, cellular, mass transport, histological) and their relationships to putative atherogenic mechanisms.

Animals↗
PubMed1981

Measuring error and sampling variation in stereology: comparison of the efficiency of various methods for planar image analysis.

An evaluation is made of the relative efficiency (precision of the final estimate per unit time of measurement on a given set of sections) of different methods for planar analysis aimed at estimating aggregate, overall stereological parameters (such as VV, SV). The methods tested are point-counting with different densities of test points (4 less than or equal to PT less than 900 per picture), semiautomatic computer image analysis with MOP and automatic image analysis with Quantimet, for obtaining VV and SV estimates. One biological sample as well as three synthetic model structures with known coefficients of variation between sections are used. The standard error of an estimate is mainly determined by the coefficient of variation between sampling units (= sections in the present paper) so that measuring each sample unit with a very high precision is not necessary. Automatic image analysis and point-counting with a 100-point grid were the most efficient methods for reducing the relative standard errors of the VV and SV estimates to equivalent levels in the synthetic models. Using a 64-point grid was as precise, and about 11 times faster than using a tracing device for obtaining the estimate of VV in the biological sample.

Animals↗
PubMed1993

Comparison of the Bio Image Visage 2000 and the GELLAB-II two-dimensional electrophoresis image analysis systems.

To compare the Visage 2000 analysis system (Bio Image, Ann Arbor, MI, USA) with the GELLAB-II analysis system (National Cancer Institute, Frederick, MD, USA), we used each to perform image analysis of the same 29 silver-stained two-dimensional electrophoresis (2DE) gel image files from a study of urinary proteins in metal recovery plant workers who had confirmed body burdens of cadmium. Visage, aided by interactive analysis, detected an average of 890 +/- 177.6 spots per gel, or a total of 25,800 spots, whereas GELLAB-II detected 1971 +/- 198.5 spots per gel, or a total of 57,160 (a 222% increase over the Visage system), without operator intervention. Visage automatically quantified 52.5% (13,556) of the spots; 47.2% (12,173), consisting mostly of larger spots, had to be quantified interactively with an image editor, and 0.3% (71) were not quantified. GELLAB-II automatically quantified all detected spots. After we interactively assigned the maximum allowed number of landmarks (30 for Visage and 52 for GELLAB-II), we found that Visage matched 657 +/- 211.2 spots per gel, and GELLAB-II matched all detected spots and also extrapolated an average of 1269 virtual spots per gel. Plots of densities from the two systems on selected spots showed excellent agreement, and both systems showed high correlation between their measurements of the beta-2-microglobulin spot densities and an independent radioimmunoassay quantification of the original urine samples. By comparing the regression of the densities of all spots with urinary cadmium (UCD) levels, we found that several of the same detected spots from each system were highly correlated. The densities of four acidic proteins with relative molecular weights of approximately 112,000 Da (as quantified by GELLAB-II but not by Visage) were highly correlated with UCD concentrations. These proteins are new candidate biomarkers of cadmium toxicity. We compared the estimated labor costs of using each system to analyse a hypothetical 20-sample (60 gels) 2DE study and found that GELLAB-II was six times less expensive to use than Visage, primarily because of the operator time required to do interactive error correction with the Visage system.

Cadmium↗
PubMed1990

Quantitative energy-filtered image analysis in cytochemistry. I. Morphometric analysis of contrast-related images.

A combination of energy-filtered electron microscopy (EFEM) and an image-analyzing system (IBAS/2000) is used for morphometric analyses of cells and (reaction) products. Image contrast is objectively established and segmentation is based upon intrinsic contrasts, in ultrathin sections. Cross-sectioned platinum-stained erythrocytes are used as a model to determine optimal conditions for constant measuring results for contrast, area and perimeter. Results are related to changes in: (1) the objective-lens diaphragm diameter, (2) three most frequently used contrast modes obtainable by electron spectroscopical imaging (ESI) in a Zeiss EM 902 transmission electron microscope (e.g., global, zero loss (or deltaE - 0 eV) and deltaE = 250 eV), and (3) the number of image integrations (1-250X) acquired by real-time video. A thresholding procedure is proposed for objective segmentation of such contrast-related images and applied to measure the area fraction of nuclear chromatin and the diameter of nominal 1 nm colloidal gold particles.

Animals↗
PubMed1994

Determination of the alpha-actinin-binding site on actin filaments by cryoelectron microscopy and image analysis.

The three-dimensional structure of actin filaments decorated with the actin-binding domain of chick smooth muscle alpha-actinin (alpha A1-2) has been determined to 21-A resolution. The shape and location of alpha A1-2 was determined by subtracting maps of F-actin from the reconstruction of decorated filaments. alpha A1-2 resembles a bell that measures approximately 38 A at its base and extends 42 A from its base to its tip. In decorated filaments, the base of alpha A1-2 is centered about the outer face of subdomain 2 of actin and contacts subdomain 1 of two neighboring monomers along the long-pitch (two-start) helical strands. Using the atomic model of F-actin (Lorenz, M., D. Popp, and K. C. Holmes. 1993. J. Mol. Biol. 234:826-836.), we have been able to test directly the likelihood that specific actin residues, which have been previously identified by others, interact with alpha A1-2. Our results indicate that residues 86-117 and 350-375 comprise distinct binding sites for alpha-actinin on adjacent actin monomers.

Actin Cytoskeleton↗
PubMed2005

Recent development of image analysis methods in plant chromosome research.

Image analysis methods have provided effective tools in chromosome research along with the development both in computer software and hardware. A chromosome image analyzing system, CHIAS, for plant chromosomes was developed in 1985 and was subsequently revised so that with CHIAS3 one can take advantage of Internet use for downloading the program. In this review, the recent developments of imaging methods in plant chromosome research for automating chromosome identification, constructing a map of a pachytene chromosome, and patterning of interphase nuclei are described.

Automation↗