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PubMed1992

Study of fibronectin and mRNA in human laryngeal and ectocervical carcinomas by in situ hybridization and image analysis.

The expression of fibronectin (FN) mRNA was studied in histological sections of surgical biopsies from human laryngeal and ectocervical invasive carcinomas of different grading stages by in situ hybridization and image analysis. This approach made it possible to identify the cell types synthesizing FN mRNA in the tissue sections and to compare semi-quantitatively the FN mRNA levels expressed in the different specimens. The carcinoma cells synthesized low levels of FN mRNA, comparable to those detected in control epithelia and connective-tissue fibroblasts. Well-differentiated (G1) laryngeal and ectocervical carcinomas induced the synthesis of FN mRNA--to levels 7 to 13 times higher than in control connective tissues--in the stromal fibroblasts surrounding the tumors. In carcinoma samples analysed, the amount of FN mRNA detected in the stroma decreased in relation to tumor grading (from G1 to G3) and the stromal destruction. FN mRNA was not detectable in the endothelial cells of venules while it was present in large amounts in those surrounding the capillaries present in the stroma. These data indicate that FN, usually observed around carcinomas, is produced by stromal fibroblasts, which are induced to express FN mRNA, presumably in response to diffusible factors produced by the tumor cells, and/or by endothelial cells of the infiltrating capillary vessels. The induction of FN mRNA, inversely proportional to the tumor grading, may be useful in evaluating the invasion potential of the tumor.

DNA Probes↗
PubMed1990

[Image analysis for measuring the rDNA transcriptional activity].

It was clearly demonstrated that the silver stainability of NORs during interphase and metaphase could be inhibited by low doses of AMD concentration. It showed that the AMD concentration could reflect the rDNA transcriptional activity in NORs. In this experiment we used HABM image analysis system to measure the variation of silver stainability of NORs treated by different doses of AMD in order to find the correlation between the rDNA transcriptional activity and the AMD concentration. The data resulted from this experiment were analysed with variance and correlation analysis method. The result showed that the variability of Ag-Nucleoli was significant in different AMD concentration and it was positively correlated with AMD concentration. So, we considered that the size of Ag-Nucleoli is one of the most precise signs when measuring the rDNA transcriptional activity with silver staining method.

Analysis of Variance↗
PubMed1984

A new image analysis method for the quantification of neovascularization.

In a foregoing paper, an attempt has been described to quantify the neovascularization in the chorioallantoic membrane (CAM) by using the method of automatic image analysis. In this case 5 to 10 min were necessary to measure the neovascular response of one CAM preparation (i.e. to obtain a value for the degree of angiogenesis). The accuracy of reproducibility of the measurements was about +/- 20%. In this paper, we describe a new method which only requires about 55 seconds for the measurement of one specimen with an accuracy of about +/- 12%.

Allantois↗
PubMed1984

Utilization of image analysis for the quantification of vascular responses in the chick chorioallantoic membrane.

An attempt has been made to quantify the vascular response in the CAM by using the method of automatic image analysis. In order to obtain a measure for the divergence of preparations with radial capillary growth from unchanged CAM preparations the lengths of radially arranged capillaries were measured, the relative frequency computed and compared with that of radially arranged capillary pieces in normal CAM preparations. The areal difference between both histograms is used as a measure for the grade of neovascularization Investigations performed to test the reproducibility and reliability of this measuring method have given a measuring accuracy of about +/- 20%; this value is comparable with that found by the method of radial vessel counting. The mean values of samples each consisting of 10 preparations obtained by the method of vessel counting and by the automatic measurement correlate quite well (r = 0.97). Angiogenic responses of different grades were produced in the CAM by dropping calf plasma on the CAM surface in amounts between 1 and 10 microliter. Although the individual values in the single groups vary within a wide range, a dose-response-relationship could be established both by the automatic measurement and by the method of radial vessel counting. Further improvements of the measuring procedure and a shortening of the measuring time from 5-10 min to 1 min or less could make this automatic method very suitable for the quantification of vascular responses in larger experimental series.

Allantois↗
PubMed1992

Image analysis of neuropil threads in Alzheimer's, Pick's, diffuse Lewy body disease and in progressive supranuclear palsy.

Neuropil threads (NT) in the middle temporal gyrus (MTG) were quantitated by computerized image analysis from five patients each with Alzheimer's disease (AD), Pick's disease (PD), and diffuse Lewy body disease (DLBD), four patients with progressive supranuclear palsy (PSP), and five cognitively normal control subjects (24 patients total). All disease groups met clinical and pathological criteria for their respective diseases. The DLBD subjects did not have pathological features of AD. Using the Gallyas silver method, the percentage of cortical area occupied by NT was calculated for each case examined and compiled for each group. Intergroup comparison revealed the percentage of cortical area occupied by NT as follows: AD, 6.87%; PSP, 1.12%; PD, 0.37%; DLBD, 0.04%; control 0.02%. The evaluation disclosed a significance level of p < 0.0001 when AD was compared to control, PD and DLBD cases and a p < 0.001 when compared to PSP. There was no statistically significant difference between control-DLBD, control-PD, control-PSP, DLBD-PSP, PD-PSP, or PD-DLBD cases (p > 0.05). These data indicate the density of neocortical threads is much greater in AD than in other dementing disorders. It also suggests that NT are not related to the intellectual decline in PD, DLBD, and PSP.

Aged↗
PubMed1994

Image analysis and categorization of ventilation-perfusion scans for the diagnosis of pulmonary embolism using an expert system.

UNLABELLED: An expert system was developed that interprets ventilation-perfusion lung scans. The use of such scans for suspected pulmonary embolism is ideal for computer-assisted diagnosis by expert systems. The data are digital, only a single disease entity is diagnosed or excluded, and well-established diagnostic criteria already exist for visual interpretation that can be easily integrated into an expert system. METHODS: This expert system is divided into two modules. The first module is responsible for image analysis. Analysis was performed on the eight standard perfusion images and on single-breath, equilibrium and 3-min washout ventilation images. Each image was analyzed for the presence of regional perfusion or ventilation defects, as determined by pixel values that fell 2.2 s.d. below the mean (or above the mean in the case of washout images) compared with a database of normal studies. The defect size, segment involved and number of defects were determined. Ventilation and perfusion images were then compared to determine whether defects were matched or mismatched. The second program module applied the modified Biello's criteria to the data and categorized the scan as normal to low, intermediate or high probability. RESULTS: A total of 80 patients were prospectively studied. An 81% (65 of 80) correlation was obtained when the results of the expert system were compared with visual interpretations made by three experienced nuclear medicine physicians. CONCLUSION: This study shows that the interpretation of ventilation-perfusion lung scans by an expert system is possible. The technique holds the promise of reducing interobserver variability and assisting less experienced observers in the interpretation of such scans.

Expert Systems↗
PubMed1998

Androgen receptors in ovarian tumors: correlation with oestrogen and progesterone receptors in an immunohistochemical and semiquantitative image analysis study.

The expression and distribution of androgen, estrogen and progesterone receptors was examined by immunohistochemical staining in 31 paraffin-embedded sections from ovarian tumors and the results were assessed by semiquantitative image analysis. Immunohistochemical staining showed heterogeneous patterns of steroid receptor distribution, with mainly nuclear immunoreactivity. Eighty-four percent of benign and malignant ovarian tumors expressed androgen receptors (AR), 74.19% estrogen receptors (ER) and 41.16% progesterone receptors (PR). All benign tumors showed immunoreactivity for the three steroid receptors. Malignant tumors expressed higher AR and ER histochemical scores (H-scores) than PR (82% vs 71% vs 39%). The incidence and expression levels of the steroid receptors varied widely in the different histological types of malignant tumors. Spearman rank analysis showed a positive significant (P < 0.05) correlation between AR- and ER and between ER- and PR-H-scores. In malignant ovarian tumors, neither AR, ER nor PR immunohistochemical scores correlated with tumor FIGO stage. Densitrometric analysis of immunostained steroid receptors is a valid method for assessing the steroid status, because it reduces subjective elements in scoring sections and increases the reliability of results. The high incidence of AR expression confirms the functional role of AR in ovarian tumors and suggests that the determination of AR content in ovarian cancer could have prognostic value.

Densitometry↗
PubMed1995

Nuclear morphometry and DNA densitometry of human gliomas by image analysis.

In 48 patients with gliomas in whom complete clinical follow-up was obtained, DNA ploidy was evaluated by using formalin-fixed paraffin-embedded tissues and by means of image analysis. The mean DNA indices, determined by averaging DNA indices of all tumor cells in a tumor, were mainly affected by mean DNA indices of the nuclei of SG2M phase tumor cell (including S phase and G2M phase cells) (SG2M DNA indices) and that mean DNA indices correlated with the SG2M phase fraction. The SG2M DNA indices and the percentage of tumor cells with S phase and G2M phase were higher in high grade gliomas including anaplastic glioma and glioblastoma multiforme than in low grade gliomas. Patients with G2M-hypertetraploid tumors demonstrated a shorter time to tumor progression than those with G2M-tetraploid in high grade glioma. Morphometrically, the nuclei of SG2M phase glioma cells were larger and more deformity than those of G0G1 phase (including G0 phase and G1 phase cells) cells. The G2M-hypertetraploid tumors were highly malignant and demonstrated large nuclei, greater nuclear deformity, and a higher proliferative potential. The G2M-tetraploid gliomas demonstrated a shorter time to tumor progression in cases whose the SG2M fraction was large. In contrast, G2M-hypotetraploid gliomas revealed an insignificant trend towards a longer time to tumor progression than those associated with tetraploid and hypertetraploid gliomas. We emphasize herein the prognostic importance of the SG2M phase cell, as well as other proliferation indices.

Adolescent↗
PubMed1999

Image analysis of morphological change during arachidonic acid production by Mortierella alpina 1S-4.

The changes in mycelial morphology during arachidonic acid (AA) production by Mortierella alpina 1S-4 were investigated using an image analysis system. Cultivation was performed in a 10-kl fermentor, and the culture broth was separated into two fractions by sieving (0.5 mm aperture size): the filament fraction (F-fraction, <0.5 mm), and the pellet fraction (P-fraction, >0.5 mm). The effect of the mycelial morphology in each fraction on AA production was analyzed. As a result, a product distribution in the culture broth wherein the AA content in the mycelia of the P-fraction was observed to be higher than that in the mycelia of the F-fraction throughout the cultivation. Morphological analysis of the P-fraction revealed that the hairy pellets became smooth because the mycelia on the pellet surface were shaved off; some pellets were broken and reduced in size. The shaved-off mycelia from the hairy pellets surface moved into the F-fraction and aggregated there. From the above findings, it was likely that the low AA content in the F-fraction was due to mycelial damage during the cultivation. In addition, the morphology of the hairy pellets was found to contribute to an increase in the viscosity of culture broth.

Journal Article↗
PubMed1992

Computer-aided classification of malignancy in astrocytomas. I. The value of nuclear parameters obtained by automated black and white image analysis.

Ninety-three selected cases of astrocytomas including glioblastomas (astrocytomas grades 1-4) were evaluated by means of Feulgen-stained microscopic slides for nuclear parameters obtained by automated black and white image analysis (ABWIA). The goal was to determine to what extent nuclear features evaluated by ABWIA were applicable as classifiers for the computer-aided numerical classification of malignancy in astrocytomas. Before the automated evaluation, all tumours had been subjectively graded according to the Mayo Clinic grading rules as delineated by Ringertz. Twenty-three nuclear parameters were evaluated and tested for their classification impact. With a model of five parameters (number of nuclei per area, mean of the convex form factor, extinction sum, extinction variation, and full-width-half-maximum of the extinction distribution) the highest reclassification rate of 75% correctly reclassified cases was obtained. Although this is a good result for a classification using only nuclear parameters, it is too poor for practical application. Thus, nuclear parameters evaluated by ABWIA alone are insufficient for numerical classification models assessing the malignant expression of astrocytomas.

Astrocytoma↗
PubMed1992

Reticulocyte quantification by flow cytometry, image analysis, and manual counting.

Reticulocyte counting by flow cytometry with thiazole orange was compared to manual or automated counting of new methylene blue stained blood smears. Forty-nine samples were compared for manual counting from randomly chosen clinical samples. Two hundred and eighty-nine samples from bone marrow transplant patients were compared during the period before and through chemo-irradiation and engraftment. The slopes of correlation plots were less than 1 when flow cytometric data were the dependent variable, suggesting that thiazole orange is less sensitive than new methylene blue. In a third study, 407 samples from bone marrow transplant patients were compared after increasing the thiazole orange concentration. The reticulocyte fluorescence distribution was divided into four groups of the brightest (youngest) 40, 60, 80, and 100% of reticulocytes. The slopes from regression analysis were 0.25, 0.49, 0.78, and 1.14, respectively. This demonstrates that thiazole orange is more sensitive than new methylene blue because the window of analysis includes an increased fraction of mature reticulocytes. In addition, the precision of each assay as measured. The rank order of precision from high to low was flow cytometry > image analysis >> manual counting.

Benzothiazoles↗
PubMed1996

Validation of an automated image analysis micronucleus scoring system.

The Loats Automated Micronucleus Scoring System was developed to assist with the evaluation of compounds for the ability to induce micronuclei in mouse bone marrow polychromatic erythrocytes (PCE). This image analysis system can identify PCE as well as normochromatic erythrocytes (NCE) and calculate the PCE/NCE ratio as an index for bone marrow toxicity. Two studies were conducted to provide slides for a comparison of micronucleated PCE values collected manually to those collected by the automated system. Mitomycin C was used as a micronucleus-inducing agent to elicit a positive response and Lilly compound 303497 was used as an example of a compound negative for the induction of micronuclei. No statistically significant differences were observed between micronucleus counts obtained manually and those obtained by the automated system. The PCE/NCE ratios calculated by the automated system were also similar to those determined from the manually collected PCE and NCE counts for the vehicle and positive controls, however, differences in the ratios were observed in compound treatment groups. These differences were attributed to a larger population of transitional cells in the treated groups. These results confirm that the Loats Automated Micronucleus Scoring System is an acceptable alternative to manual evaluation of mouse bone marrow slides for the incidence of micronucleated PCE.

Animals↗
PubMed1997

Rapid nodule evaluation computer-aided image analysis procedure for bone nodule quantification.

Using bone cell cultures, the effects of drugs on cell activities such as proliferation, differentiation, matrix formation, and mineralization can be explored. To quantify these parameters accurately and quickly, a kinetic reproducible computed image analysis procedure of culture dishes is proposed which could be conjointly used with biochemical analysis of the medium. In the present article, different mathematical procedures coupled either with or without histochemical staining are investigated and analyzed. Using serial cross sections and microradiographies of bone nodules, we demonstrated that the gray-level parameter is well correlated with bone mass and/or the mineralization status of the nodules. The procedure selected is a multistep procedure called rapid nodule evaluation (RNE), which uses a binary reconstruction program with different thresholds. To challenge this RNE procedure with the classical Von Kossa staining and quantification procedure, we cultured the cells in the presence of 10 nmol/L dexamethasone and compared the results using the two procedures. The RNE procedure appeared to be accurate and reproducible, and also has the advantage of speed and dynamic analysis over the classical Von Kossa quantification procedure.

Animals↗
PubMed1994

Investigation of blood-brain barrier permeability by means of computerized image analysis.

Intravital fluorescence microscopy has been widely used to study changes of blood-brain barrier (BBB) permeability in vivo. However, quantification of tracer extravasation by counting leaky spots provides only a rough estimate of permeability increase. We have therefore developed a new method for measurement of tracer extravasation from cerebral blood vessels by combining image analysis techniques with intravital fluorescence microscopy. This method is based on generation of subtraction images after shading and displacement correction. Subtraction images are further processed to eliminate noise and diminish artefacts due to vessel distortion and/or dilatation. The "degree of extravasation" (E(f) value) which is then calculated takes into account the number and size of leaky spots as well as their intensities. Examples are shown to illustrate that pure vasodilatation does not increase E(f) as long as the BBB-permeability is not disturbed. This newly developed method may prove helpful for comparison of tracer extravasation under different experimental conditions.

Animals↗
PubMed2003

Sequential image analysis and measurement of pigmented lesions: false variations due to patient positioning.

Clinical researchers are evaluating the utility of obtaining sequential images of pigmented lesions taken over time for purposes of comparison with the aim of detecting subtle changes suggestive of melanoma. Therefore, the image acquisition process is critical and will need to be strictly standardized before any firm conclusions can be drawn from analysis of sequential images. The influence of patient positioning on the accuracy of sequential image analysis has not been considered in most studies evaluating sequential images. In this experimental study, the influence of patient positioning on the size and shape of an inked circle placed on the skin was determined and measured. Inked circular marks (15 mm in diameter, area 176.71 mm2) were placed on the skin of the lumbar and suprascapular areas of 60 consecutive patients. The diameter and area of the 'circle' was measured with the patient in the prone position with head centred, prone position with head turned to the right, prone position with head turned left, and in the seated position. Statistical analysis was performed with Student's t-tests (paired data). We observed statistically significant differences in the shape, mean maximal diameter and area of the inked circular marks on both the suprascapular area and in the lumbar area after changes of patient positioning (P<0.001). To conclude, the position of the patient must be fixed and standardized during acquisition of sequential images, at least for lesions 15 mm in diameter or larger. Furthermore, it is our opinion that the methods used to control for patient positioning should be reported in the methodology section of studies that report on comparison of sequential images. Only then can we accurately compare sequential images and avoid 'false positive lesion enlargement' being categorized as a true change.

Adolescent↗
PubMed2002

Inclusion counter: a public domain image analysis system for measurement of Chlamydiaceae growth in vitro.

The traditional method of measuring chlamydial growth in vitro, counting Chlamydiaceae inclusions by eye, is time-consuming and error prone. This paper describes a novel automated image analysis system suitable for high-throughput screening of novel anti-Chlamydiaceae compounds. The software, Inclusion Counter v3.0, is freely available in the public domain (http://www.image-analysis.co.uk).

Animals↗
PubMed1992

Electron microscopy and image analysis of the GroEL-like protein and its complexes with glutamine synthetase from pea leaves.

The molecular structure of GroEL-like protein from pea leaves has been studied by electron microscopy and image analysis of negatively stained particles. Over 1500 molecular projections were selected and classified by multivariate statistical analysis. It was shown that the molecule consists of 14 subunits arranged in two layers with 72 point group symmetry. Side view projections of the molecule show a four-striation appearance, which subdivides both layers of seven subunits into two halves; this may be explained by a two-domain structure of the subunits. The presence in protein preparations of projections corresponding to one layer of subunits or half-molecules is consistent with the molecular structure suggested. Electron microscopic evidence for a specific association of GroEL-like protein and octameric glutamine synthetase, which was co-purified with this protein, was obtained.

Bacterial Proteins↗
PubMed1983

Computerized image analysis for quantitative measurement of vessel diameter from cineangiograms.

Subjective estimates of the angiographic severity of coronary artery stenoses show variability and inaccuracy. We therefore tested the accuracy of a newly developed computerized image analysis system for quantitating vessel diameter from cineangiograms. Fourteen cylindrical phantoms of known diameter were filled with contrast medium and filmed over a wide range of clinically relevant radiographic conditions in order to develop regression equations that related computer-derived to anatomic diameters. Computer measurements of vessel diameter were unaffected by vessel size, magnification, focal spot size, thickness of scattering medium, kilovolt peak, or location within the radiographic field, but a correction factor was necessary for a small but significant (p less than .01) linear dependence on contrast medium concentration. The accuracy of computerized vessel diameter measurements ranged between +/- 59 and +/- 137 mu for all conditions except for rapid vessel motion and contrast medium concentrations of 50% or less meglumine diatrizoate (Renografin 76), both of which resulted in reduced accuracy as well as in the inability to locate lumen edges of vessels less than 1 mm in diameter.

Cineangiography↗