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[Automatic image analysis in the study of the microcirculatory bed].

The authors discuss the possibility of efficient morphometric analysis of capillary architectonics and pathological structural changes in microcirculatory bed with computer systems of image analysis using selective histological staining of microvessels. It is suggested that a histochemical method of alkaline phosphatase identification is used for cerebral, cardiac, adrenal, hepatic, splenal, gastrointestinal, sceletal muscle, testes, urine bladder, serosae and other rat organ capillaries computerized analysis. It is recommended to impregnate the microcirculatory bed of bigger omentum of large laboratory animals according to V. Kupriyanov's method, and to stain the labrocytes of the perivascular loose connective tissue of serious membranes in large laboratory animals with alcohol solution of toluidine blue.

Animals↗

Quantification in the subnanomolar range of phospholipids and neutral lipids by monodimensional thin-layer chromatography and image analysis.

A sensitive, rapid, and simple method is presented for the simultaneous quantitation of the major phospholipids and neutral lipids using an image analyzer after separation by one-dimensional thin-layer chromatography. A clear-cut separation of the lipids was achieved on one EDTA-impregnated chromatoplate with five step-wise developments. An image was acquired, and the integrated optical densities of the individual spots were quantitated by a camera-equipped image analyzer against an internal standard of cholesteryl formate. Calibration curves for each lipid followed linear or hyperbolic functions permitting quantification of as little as 0.015 nmol of lysophosphatidylcholine and as much as 7.50 nmol of triglyceride from a single application. Quantitation of the major lipids in human plasma by TLC and image analysis and standardized enzymatic methods were well correlated. The method is suitable for routine analysis of biological samples having lipid profiles as different as rat hepatocyte subcellular fractions, and very low density lipoproteins secreted by rat hepatocyte suspensions.

Animals↗

A simple method to 'point count' silt using scanning electron microscopy aided by image analysis.

This study presents a simple method to 'point count' silt-sized grains using backscattered scanning electron microscopy together with image analysis. The work materialized out of the need to determine the heavy mineral abundance within silt obtained from coastal dunes to aid in the interpretation of dune weathering. This technique allows two broad mineral groups to be quantified according to their modal abundance. The groups are characterized by their dominant atomic elements present; atomic numbers >20 are classified as 'high' (metal oxides, zircon, monazite, carbonates, pyroxenes and amphiboles) and those <20 as 'low' (quartz, feldspars and organics). As a check on this technique, X-ray fluorescence was used. This showed a strong positive correlation (r2=0.85) with the developed point counting technique.

Image Processing, Computer-Assisted↗

An automated image analysis method for the measurement of neutrophil alkaline phosphatase in the prenatal screening of Down syndrome.

OBJECTIVES: (1) To develop an image analysis method for the measurement of neutrophil alkaline phosphatase (NAP); (2) To establish a correlation of urea-resistant fraction of NAP (URNAP)/NAP scoring between the manual and automated methods, and (3) to assess the value of URNAP/NAP in the prenatal screening of Down syndrome. STUDY DESIGN: Slides from 15 unaffected controls were blindly scored by both methods. The Pearson test was used for correlation analysis. Slides from 15 Down syndrome pregnancies and 25 unaffected controls were scored manually. RESULTS: A coefficient r = 0.93 was obtained comparing the URNAP/NAP scores generated by the two methods. Average time for scoring by the automated method was 8 min. The median URNAP/NAP values for Down syndrome and unaffected controls were 112/86.1 and 51/51.5, respectively. CONCLUSIONS: Scores obtained by both methods highly correlate. Automated scoring is threefold faster. Down syndrome cases have higher URNAP/NAP scores compared to unaffected controls, which suggests that URNAP/NAP is an extremely useful marker for mid-trimester prenatal screening.

Alkaline Phosphatase↗

Characterization of Azotobacter vinelandii aggregation in submerged culture by digital image analysis.

A simple and accurate method for determining the distribution of sizes of single cells and aggregates of Azotobacter vinelandii by image analysis has been developed. A staining procedure using methylene blue helps to enhance the contrast between aggregates and background without altering aggregate size distribution. Sample dilution affected the distribution of the population and therefore should be avoided. Mixing and aeration conditions during culture play an important role in the aggregation of A. vinelandii. Cells grown under mild mixing conditions (unbaffled flasks) presented a thick slime layer and formed aggregates of up to 35 microm of average equivalent diameter. In contrast, under strong agitation conditions (baffled flasks) practically no aggregates were formed throughout cultivation. The method described can be used for the characterization of aggregation of other microbial cultures.

Anaerobiosis↗

Computerized detection of pulmonary embolism in spiral CT angiography based on volumetric image analysis.

A fully automated method for computerized detection of pulmonary embolism in spiral computed tomography angiography was developed based on volumetric image analysis. The detection method is based on segmentation of pulmonary vessels to limit the search space, and analysis of several three-dimensional features inside segmented vessel volume. The features utilized are vascular size, local contrast based on mathematical morphology, degree of curvilinearity based on second derivatives, and geometric features such as volume and length. Detection results were obtained for 19 clinical data sets and the performance of the method was evaluated. Using the number and locations of thrombi diagnosed by radiologists as the gold standard, 100% sensitivity was achieved with 7.7 false positives per case, and 85% sensitivity was obtained with 2.6 false positives. For identification of all the positive cases as positive, i.e., detection of at least one thrombus per positive case, 1.9 false positives per case were obtained. These preliminary results suggest that the method has potential for fully automated detection of pulmonary embolism.

Algorithms↗

Objective identification of cell cycle phases and subphases by automated image analysis.

Frequency distributions of integrated optical density, perimeter, projection, area, form factor, average optical density, and mean dispersion path of nuclear images of Feulgen-stained HeLa S3 cells were obtained by automated image analysis at the base threshold of 0.04 OD. The mean values and standard deviations of these geometric parameters were then computed versus increasing values of threshold (0.08--0.32 OD). There is clear evidence of differential chromatin dispersion and convolution during the cycle of synchronized HeLa S3 cells at different times after selective mitotic detachment. The combination of average OD, form factor, and mean dispersion path at base threshold with the threshold dependence of nuclear morphometric parameters permits objective identification of cell cycle phases and their subphases, by characterizing variations in chromatin geometry within and between phases, regardless of whether DNA content remains constant (early G1, middle G1, late G1), varies only slightly (late G1-early S or late S-G2 transitions), or varies significantly (early S-middle S).

Autoanalysis↗

Ageing of the skin: study of elastic fiber network modifications by computerized image analysis.

We quantitated the skin elastic fibers of the papillary and reticular dermis using specific staining procedure followed by automated computerized image analysis. Fifty skin biopsies of patients consulting for cardiovascular risk factors were studied. The following parameters were estimated: surface area (% of total surface), length, and number of fibers as a function of age. The evaluation of the skin elastic fiber system showed no significant trend with age in the number of elastic fibers per unit area in the superficial or deep dermis. We found, however, a continuous increase with age in the relative surface area, and the length of the elastic fiber system. These results can best be interpreted as a continuous apposition of elastic-type material to the preexisting fibers by skin fibroblasts. This material may well be of a different composition than young elastin, for instance enriched in structural glycoproteins (microfibrils), lipids and calcium as found in the elastic fibers of aorta and lung. Such quantitative modifications may explain the decrease in skin elasticity, and the continuous increase in stained fibers.

Adult↗

A standardized automatic procedure to evaluate cell numbers in low cell density tissues by image analysis: application to the Staggerer mutant mouse cerebellum.

To obtain a reliable and fast quantification in low cell density tissues, we have developed a standardized procedure based on image analysis. The successive steps of quantification, starting with the necessary histological procedure and ending with the desired quantitative parameters, are described. Excepting the histological procedure, we have attempted to automate all the subsequent steps of the experiment, especially the acquisition of the data by an image analyser TAS (Leitz), and the storage and the analysis of these data by a PDP 11-34 computer. The final parameters calculated by such a method are the total number of cells and the cell density within the organ under study, either for all the cells, or for different cellular categories. This procedure has been applied to the quantitative study of cerebellar cells of an adult Staggerer mutant mouse and the results obtained are presented.

Animals↗

Mechanical tension and movement in the chick blastoderm as studied by real-time image analysis.

The mechanical activity of embryonic cells was studied in vitro in whole gastrulating chick blastoderms by means of video-image analysis. Displacements of identified points were recorded and interpreted in terms of deformation and active movement. From the deformations of the vitelline membrane to which blastoderms attach by the edge cells, it was deduced that the blastoderms developed and maintained a tension of 1-1.2 X 10(4) dyn/cm2. This tension was generated by a radial contraction of cells situated in the area opaca. This contraction stretched the area pellucida where the embryogenesis took place. Additional experimentally induced distension of the vitelline membrane affected the migration of the edge cells and the formation of the primitive streak. Decrease in temperature, anoxia, colchicine, and cytochalasin B relaxed the tension in the membrane but resulted in different deformation patterns in the blastoderm. A focalized electrical stimulation led to local contractions of cells in all regions of the blastoderm except the edge cells. The tension within the contracted cells increased up to 4 X 10(4) dyn/cm2. In the area pellucida, movements of migrating mesoblastic cells showed periodic saccades lasting about 5 min. Repetitive electrical stimuli applied at the same period induced ectopic migration of cells in the area pellucida but not in the area opaca. These results are discussed with respect to factors possibly modulating the activity of embryonic cells during early morphogenesis.

Animals↗

Automated three-dimensional image analysis of thick and overlapped clusters in cytologic preparations. Application to cytologic smears.

Methods are presented for automated analysis of thick and heavily overlapped regions of cytologic preparations, such as cervical/vaginal smears. Current systems are unable to process these regions although they contain diagnostically valuable information. We argue that analysis of such regions is inherently a three-dimensional (3-D) problem that cannot be solved reliably with conventional two-dimensional methods. Furthermore, this issue cannot be side-stepped by special thin preparation methods. Even with 3-D imaging, analysis of these regions is complicated by the high variability in the image gray level and textural features resulting from the uncontrollable cell overlaps and folds and large computational requirements. A novel approach based on 3-D imaging and adaptive 3-D analysis algorithms based on the principles of localization, adaptive data reduction and clustering theory is presented. It was successful in detecting and separating deeply embedded and overlapping nuclei, cytoplasmic folds and creases in thick and overlapped regions of conventional smears and special thin preparations.

Cytological Techniques↗

Digital image analysis system for the quantification of infiltrates and cell adhesion molecules in inflammatory cardiomyopathy.

BACKGROUND: We attempted to develop a digital image analysis (DIA) system for endomyocardial biopsies (EMBs) to reliably quantify a) biopsy quality, b) immunohistochemically-marked infiltrates, and c) cell adhesion molecules (CAMs) in relation to net heart area (HA) for the semi-automated diagnosis of inflammatory cardiomyopathy (InfCM). MATERIAL/METHODS: 140 EMBs from dilated cardiomyopathy (DCM) patients and 14 autopsy heart samples (controls) were immunostained for T-lymphocytes (CD2, CD3, CD4, CD8), beta(2)-integrin+ infiltrates (CD18, LFA-1, Mac-1) and CAMs (immunoglobulin superfamily: ICAM-1, HLA class I, HLA DR, VCAM-1, CD58; selectins: CD62E and CD62P; and the beta(1)-integrin chain CD29). EMB quality was assessed visually on a three-point scale. Infiltrates were quantified visually (per hpf) and by DIA (per mm2 HA). CAM expression was evaluated semiquantitatively and by DIA (area fraction [AF]: stained area relative to HA). RESULTS: DIA-evaluated HA correlated significantly with the visual assessment of EMB quality. The visual evaluation of both infiltrates and CAMs correlated significantly with the respective DIA-based quantification. DIA-quantified CAM-AF and infiltrates were discriminated by the CAM classification (CAMs+: n=87; 62%) compared to controls. DIA-quantified CAM immunoreactivity correlated significantly with the DIA-quantified counter-receptor+ infiltrates. DIA evaluation of biopsy quality, infiltrates, and CAMs was devoid of inter- and intraobserver variability. CONCLUSIONS: The DIA system presented here enables standardized and observer-independent assessment of EMB quality and intramyocardial inflammation (density of infiltrates and CAM expression) in DCM biopsies related to HA. Our data confirm that endothelial CAM count and counter-receptor+ immunocompetent infiltration are interdependent pathogenic and diagnostic hallmarks of InfCM.

Adult↗

AMIDE: a free software tool for multimodality medical image analysis.

Amide's a Medical Image Data Examiner (AMIDE) has been developed as a user-friendly, open-source software tool for displaying and analyzing multimodality volumetric medical images. Central to the package's abilities to simultaneously display multiple data sets (e.g., PET, CT, MRI) and regions of interest is the on-demand data reslicing implemented within the program. Data sets can be freely shifted, rotated, viewed, and analyzed with the program automatically handling interpolation as needed from the original data. Validation has been performed by comparing the output of AMIDE with that of several existing software packages. AMIDE runs on UNIX, Macintosh OS X, and Microsoft Windows platforms, and it is freely available with source code under the terms of the GNU General Public License.

Costs and Cost Analysis↗

FAZYTAN: a system for fast automated cell segmentation, cell image analysis and feature extraction based on TV-image pickup and parallel processing.

Cell location, segmentation and feature extraction of cell images are principal tasks of a high-resolution system for automated cytology. To perform these tasks with high speed, image processing algorithms and the architecture of a processor have to be optimized mutually. This has led to the development of a fast system for the evaluation of cytologic samples based on an optimized TV microscope, a host minicomputer with different peripheral array processors and digital image storages. The processors are optimized in speed for two-dimensional local operations to investigate neighborhood relations and morphology in cell images. Two-dimensional transformations of TV images (288 x 512 x 8 bit) can be carried out within 20 to 200 msec. The processors are able to realize linear filter functions (correlation, convolution) as well as nonlinear functions (median filtering). A set of measurements like area, circumference and connectivity can be derived parallely from one image in 20 msec. The system performs efficient and fast detection and segmentation of cells scanned in one TV frame within one second as well as the extraction of a large number of morphologic features within a few seconds. Based on these procedures, high-resolution analysis of several thousand cells of a sample within one minute will be possible.

Autoanalysis↗

Determination of proliferation index with MIB-1 in advanced ovarian cancer using quantitative image analysis.

A new monoclonal antibody, MIB-1, reacts with the same epitope recognized by Ki-67. The authors investigated the feasibility of using image analysis to quantitate the MIB-1 staining (proliferation index [PI]) of epithelial ovarian cancers. The PI was determined in 50 advanced-stage primary ovarian cancers. Paraffin sections were immunostained with the MIB-1 monoclonal antibody, and the PI was calculated using a CAS 200 image analyzer. Among 36 stage III ovarian carcinomas, the median PI was 15.1%, compared with 18.9% in 14 stage IV cancers (P = .47). Based on exploratory methods, a cutoff point of 7% best dichotomized these patients into two prognostic groups. Of 39 patients whose cancers had a high MIB-1 expression (> or = 7%), the median survival was 16.5 months, which differed significantly (P = .01) from the median survival of 33.2 months observed in the 11 patients whose tumors demonstrated low MIB-1 expression (< 7%). Using MIB-1 as a binary variable, a strong correlation was found between overexpression of c-erbB-2 (2+ and 3+) and MIB-1 > or = 7% (P = .001). No relationship was found between PI and histologic grade. Further studies are warranted to investigate the relationship between MIB-1, PI expression, and other known clinicopathologic and genetic features of early- and late-stage ovarian cancer.

Antibodies, Monoclonal↗

Digital image analysis of haematopoietic clusters.

Counting and differentiating cell clusters is a tedious task when performed with a light microscope. Moreover, biased counts and interpretation are difficult to avoid because of the difficulties to evaluate the limits between different types of clusters. Presented here, is a computer-based application able to solve these problems. The image analysis system is entirely automatic, from the stage screening, to the statistical analysis of the results of each experimental plate. Good correlations are found with measurements made by a specialised technician.

Blood Cell Count↗

[Gingival grafts: evaluation of recovering surfacic quantimetry by image analysis].

24 gingival recessions were treated with free gingival autografts. The root coverage was evaluated by a new method: surfacic quantimetry by image analysis. This present study compares the linear and surfacic results. After statistic study, the linear coverage was evaluated at 26.74% (+0,813 mm for an initial height of 3,040 mm) and the surfacic coverage at 19.10% (+1,223 mm2 for an initial surface of 6,400 mm2).

Gingiva↗