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PubMed1998

High contrast and homogeneous staining of paraffin sections of whole human brains for three dimensional ultrahigh resolution image analysis.

The gallocyanin chromalum stain belongs to the classical DNA-RNA staining techniques in histochemistry. It has some important features for successful object orientated image analysis of whole sections of the human brain. To obtain reproducible staining results with these large sections, the method of Einarson was adapted to image analytical requirements. We discuss staining in a warm staining solution, pH adjustment, and optimal stain composition. The embedding procedure for whole human brains is considered as well.

Brain↗

PubMed1992

Comparison of cell proliferation in breast carcinoma using image analysis (Ki-67) and flow cytometric systems.

Cellular proliferation has been implicated as an important predictor of biologic behavior in breast cancer. Cellular proliferation of 95 breast carcinomas was evaluated by comparing Ki-67 immunoreactivity in frozen sections quantitated by image analysis with S-phase and S + G2/M phase fraction determined by flow cytometry on nuclei extracted from fixed, paraffin-embedded sections (modified Hedley's technique). These parameters were correlated with traditional morphologic features of histologic grade, including mitotic count. Ki-67 immunoreactivity correlated with S-phase fraction determined by flow cytometry (r = .41, P = .001) and with S + G2/M phase fraction determined by flow cytometry (r = .29, P = .008). There was also a correlation between histologic grade and Ki-67 immunoreactivity (r = .30, P = .004) and between histologic grade and S-phase fraction (r = .42, P = .0001). Mitotic count correlated with Ki-67 immunoreactivity (r = .25, P = .015) and with S-phase fraction (r = .35, P = .001). Image and flow cytometric analysis systems provide comparable measurements of cellular proliferation; their measurements correlate with histologic grade and mitotic count in breast cancer.

Breast Neoplasms↗

PubMed2000

Determination of yeast glycogen content by individual cell spectroscopy using image analysis.

A rapid technique has been developed to determine the glycogen content of yeast on an individual cell basis using a combination of image analysis technology and staining of yeast cells with an I(2):KI solution. Changes in mean cellular glycogen content during alcoholic fermentation have been reported using this technique. The glycogen content of stored brewer's yeast is heterogeneous compared to freshly propagated yeast which have a more uniform distribution of glycogen. Analysis of the distribution of yeast glycogen during fermentation indicates that a fraction of yeast cells do not dissimilate glycogen. Therefore, conventional analysis of the mean glycogen content of yeast used to inoculate fermentations is of limited use, unless information regarding the proportion of cells which utilize glycogen is known. Analysis of the distribution of glycogen within a yeast population can serve as a useful indicator of yeast quality.

Aerobiosis↗

PubMed1989

Discrimination of benign versus malignant mixed tumors of the salivary gland using digital image analysis.

Seven benign and four malignant mixed tumors of the salivary gland, biopsied using fine-needle aspiration, were analyzed using digital image analysis. Mean nuclear form factor, perimeter, and area were significantly increased in malignant cases. Better separation between diagnostic categories, however, was achieved by utilizing the coefficient of variation (CV) within a case rather than mean value. Form factor CV alone divided cases into nonoverlapping diagnostic categories. This quantitative analog of "pleomorphism" provided a useful marker for malignancy in mixed tumors.

Adenoma, Pleomorphic↗

PubMedDate not supplied

Digital image analysis of platelet-extracellular matrix interactions: studies in von Willebrand disease patients and aspirin-treated donors.

We have developed an automated image analysis method which provides en face morphometric evaluation of platelet interactions with coverslips coated with extracellular matrices. This procedure gives also additional information on the intensity of platelet-surface interactions in the same specimens. To standardize the method, anticoagulated human blood was flowed at 800 s-1 during 10 min at 37 degrees C through a parallel perfusion chamber in which extracellular matrix (ECM)-coated coverslips were placed. The sensitivity of the new method was tested in similar studies performed in patients with von Willebrand disease or treated with aspirin (500 mg/day). The extent of platelet deposition on the ECMs was evaluated by both standard and new morphometric procedures. Coverslips were successively embedded in resin and processed for cross-sectional analysis and results were compared with those provided by the new automated procedure. A good correlation was found between results of covered surface obtained by both methods (r = 0.86; p < 0.005). Results from perfusions performed with blood from patients with platelet defects confirmed the correspondence of grey levels in the digitized images with the heights of groups of interacting platelets calculated from cross sections. The new automated method, in only one stage, allows a reliable evaluation of the global interaction of platelets with the ECM and effectively detected qualitative modifications in platelet-platelet interactions in patients with known platelet defects. The method described could be applied to the evaluation of the interactions of platelets with purified components of the subendothelium.

Aspirin↗

PubMed2003

Application of a new image analysis technique to study brain asymmetry in schizophrenia.

The hypothesis that normal brain torque (i.e. rightward frontal and leftward occipital asymmetry) is anomalous in schizophrenia (Crow, 1997. Trends in Neuroscience, 20, 339-343) was tested by application of a novel image analysis technique on three-dimensional magnetic resonance images obtained in 26 adult patients with chronic schizophrenia (18 males, 8 females) and 24 controls (14 males, 10 females). Right and left cerebral hemisphere tissue was extracted via non-linear co-registration with a mask image, and maps were computed of inter-hemispheric differences in tissue volume in an array of columns of voxels orthogonal to the mid-plane (2D), and profiles of coronal slice volumes (1D). Furthermore, integration of two-dimensional column maps gave approximate lobar asymmetries, and occipital and frontal asymmetries were combined to give a volumetric measure of brain torque. Significant brain torque was revealed in male and female control and patient groups, and did not correlate with brain size. Frontal and occipital asymmetries were significantly correlated in all groups. Both frontal and occipital components of torque were significantly increased in males than females. Patients tended to have reduced torque, particularly the leftward occipital component. Furthermore, 3/26 patients (but no controls) had reversed torque (leftward frontal and rightward occipital asymmetry). Contrary to Crow's hypothesis, brain torque was not significantly reduced in patients with schizophrenia relative to controls, although reversal of torque was found in three cases. Future studies with larger sample sizes should consider sexual dimorphism and specific symptoms in relation to asymmetry.

Brain↗

PubMed2004

Monitoring activated sludge settling properties using image analysis.

The goal of this study is to develop a monitoring system for activated sludge properties, as this is an essential tool in the battle against filamentous bulking. A fully automatic image analysis procedure for recognising and characterising flocs and filaments in activated sludge images has been optimised and subsequently used to monitor activated sludge properties in a lab-scale installation. The results of two experiments indicate that the image information correlates well with the Sludge Volume Index. It is shown that, at the onset of filamentous bulking, there is an increase in total filament length on the one hand, and a change in floc shape on the other hand.

Automation↗

PubMed1994

Three-dimensional imaging and image analysis of hippocampal neurons: confocal and digitally enhanced wide field microscopy.

The microscopy of biological specimens has traditionally been a two-dimensional imaging method for analyzing what are in reality three-dimensional (3-D) objects. This has been a major limitation of the application of one of science's most widely used tools. Nowhere has this limitation been more acute than in neurobiology, which is dominated by the necessity of understanding both large- and small-scale 3-D anatomy. Fortunately, recent advances in optical instrumentation and computational methods have provided the means for retrieving the third dimension, making full 3-D microscopic imaging possible. Optical designs have concentrated on the confocal imaging mode while computational methods have made 3-D imaging possible with wide field microscopes using deconvolution methods. This work presents a brief review of these methods, especially as applied to neurobiology, and data using both approaches. Specimens several hundred micrometers thick can be sampled allowing essentially intact neurons to be imaged. These neurons or selected components can be contrasted with either fluorescent, absorption, or reflection stains. Image analysis in 3-D is as important as visualization in 3-D. Automated methods of cell counting and analysis by nuclear detection as well as tracing of individual neurons are presented.

Animals↗

PubMed1992

Image analysis of gap junction structures.

Isolated gap junction plaques contain hexagonal crystalline arrays of membrane channels called connexons which are a suitable specimen for electron crystallography. Image analysis of gap junction lattices has shown that while there is sufficient lattice order for structural analysis to approximately 25 A, there is enough disorder in both the lattice and the connexon to create a family of related images. This review is focused on how these images can be interpreted in terms of what is known about both the connexon and its constituent protein, connexin.

Animals↗

PubMed1990

Quantitative morphological study of Langerhans cells by computerized image analysis.

ATPase-stained normal and topical nitrogen mustard treated Langerhans cells (LC) in guinea pig epidermis were studied quantitatively and morphologically by computerized image analysis. Significant correlation and linear regression were found between the perimeter and square root of its area for both cytoplasm and nucleus; a theoretical basis was thus given for morphological identification of LC. The directly measured and derived geometric parameters indicated not only substantial alteration of cytoplasm morphology of post-treated LC such as cytoplasmatosis and dendrites reduction but also a potential change of nuclear size and functional status. We conclude that quantitative morphological analysis is an objective, precise and practical method for LC research.

Animals↗

PubMed2005

Quantitative kinetics of damage and recovery of cytoskeletal structure by means of image analysis.

The cytoskeleton is a network of proteins which structurally and dynamically organise the cytoplasm of living cells. Microtubules are among its constituents. Morphological alterations of microtubules are related to functional impairment. Therefore cytoskeletal morphology is a valuable indicator of cell injury and functionality. This paper focuses on the comparison between normal and altered cytoskeletal microtubules by means of image analysis and classification with the aim of replacing visual assessment. Morphology has been quantified by the extraction of some descriptors yielded by spatial differentiation, fractal analysis and Fourier analysis followed by non-linear filtering. The principal component analysis of these descriptors has led to image recognition and has been applied to hepatocytes and fibroblasts exposed to some xenobiotics. In the case of hepatocytes, images have been ranked according to the severity of cytoskeletal damage, a dose-response relation has been derived from the regression of the first principal component and the percentage of structural recovery after exposure has been estimated.

Algorithms↗

PubMed1992

Cirrhotic changes in livers from children undergoing transplantation. Image analysis.

The pattern and extent of disorganization of the liver architecture were studied in 25 children undergoing orthotopic liver transplantation for cirrhosis. Image analysis techniques based on mathematical morphology were used to define seven parameters for each case, including fibrosis index (percentage of Sirius-red-stained areas), three categories of regenerative nodules (< 0.8, 0.8-1.6 and > 1.6 mm in diameter) and three categories of fibrous septa (< 0.4, 0.4-1.2 and > 1.2 mm in width). Fibrosis index ranged from 10.2% to 51.9%. Percentage of small nodules of infralobular size (< 0.8 mm in diameter) varied from 31.4% to 98.2%. Percentage of large nodules, > 1.6 mm in diameter, in only four cases was > 15%. Multivariate clustering analysis classified the cases into three main groups. One of them included only cases of cirrhosis secondary to parenchymal disease or to inborn errors of metabolism. In their pattern, tiny nodules predominated, and the percentage of slender septa, < 0.4 mm in diameter, was very high, although the overall fibrosis index was relatively low. Patients with biliary cirrhosis were classified into two groups. In one the fibrosis index was low and the size of the nodules variable, with 12% large nodules. In the other the fibrosis index was high, and small nodules, < 0.8 mm in diameter, predominated. No relationship was found with age at transplantation or previous portoenterostomy. A presumptive explanation for this divergent evolution might be the occurrence of cholangitic episodes. Overall fibrosis that the liver can sustain without failure is apparently limited.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1987

Image analysis of trabecular structure of the acetabulum in cadavers.

Trabecular structure of the acetabulum was studied in adult cadavers by means of image analysis. Two groups of trabecular patterns were distinguished in terms of orientation with reference to the frontal plane: one group runs concentric to the articular surface of the acetabulum, and the other rises perpendicular from it and runs radially. The density of the trabeculae tends to decrease with age, and density differences with age are more marked in non-weight-bearing than in weight-bearing regions. Older females, in comparison with males of the same age group, show lower trabecular density in non-weight-bearing regions. Regional differences were also noted with higher density in the anterosuperior and posteroinferior regions, decreasing centripetally from the margin of the acetabular fossa. The average density in weight-bearing regions was 6 per cent higher than that of non-weight-bearing regions. According to these findings, the trabecular pattern of the acetabulum has a structure responding to compressive and tensile stresses applied to the hip joints.

Absorptiometry, Photon↗

PubMed1985

Specific cytochemical stains in the image analysis of subcellular organelles.

This paper describes our work concerning densitometry and morphometry of subcellular structures in thin sections. The techniques of automatic image analysis were applied to light and electron microscopic observations of enzymatically stained lysosomes, renal brush borders and mitochondria (in human and rat kidney) and peroxisomes (in human liver). To obtain significant measurements of the enzymatic activity, specific staining techniques were developed and applied, including an improved staining of acid phosphatase for lysosomes. Optical densities were obtained by videodensitometry and electron densities of peroxisomes were obtained by digitizing and processing scanning transmission electron microscopic images. In subsequent steps, delineations and parameter estimation are performed by software. Included was an examination of delineation techniques, which showed improved results from the use of a newly developed local boundary search algorithm. The combination of these techniques was used to study changes in peroxisome and lysosome compartment in liver and kidney, some results of which are also reported.

Acid Phosphatase↗

PubMedDate not supplied

Development of an image analysis system to monitor the retention of residual cytoplasm by human spermatozoa: correlation with biochemical markers of the cytoplasmic space, oxidative stress, and sperm function.

A method has been developed for quantifying the residual cytoplasm present in the midpiece of human spermatozoa, based upon the imaging of NADH oxidoreductase activity. This procedure used NADH and nitroblue tetrazolium as electron donor and acceptor, respectively, and resulted in the discrete staining of the entire midpiece area, including the residual cytoplasm. Image analysis techniques were then used to generate binary images of the midpiece, from which objective measurements of this cellular domain could be undertaken. Such data were found to be highly correlated with biochemical markers of the cytoplasmic space, such as creatine kinase (CK) and glucose-6-phosphate dehydrogenase (G-6-PDH), in sperm populations depleted of detectable leukocyte contamination. Morphometric analysis of the sperm midpiece was also found to reflect semen quality in that it predicted the proportion of the ejaculate that would be recovered from the high-density region of Percoll gradients and was negatively correlated with the movement and morphology of the spermatozoa in semen. Variation in the retention of excess residual cytoplasm was also associated with differences in the functional competence of washed sperm preparations, both within and between ejaculates. Thus, within-ejaculate comparisons of high- and low-density sperm subpopulations revealed a relative disruption of sperm function in the low-density fraction. This disruption was associated with the presence of excess residual cytoplasm in the midpiece, high concentrations of cytoplasmic enzymes, and the enhanced-generation reactive oxygen species (ROS). Functional differences between individual high-density Percoll preparations were also negatively correlated with the area of the midpiece and the corresponding capacity of the spermatozoa to generate ROS. These findings suggest that one of the factors involved in the etiology of defective sperm function is the incomplete extrusion of germ cell cytoplasm during spermiogenesis as a consequence of which the spermatozoa experience a loss of function associated with the induction of oxidative stress.

Biomarkers↗

PubMed2002

Binary and mixed population biofilms: time-lapse image analysis and disinfection with biocides.

Simultaneous binary population biofilm formation by a bacterium and filamentous fungus was demonstrated by time-lapse image analysis in a flow cell system. The accumulation of attached bacterial cells followed an S-shaped graph similar to batch culture bacterial growth, with continual attachment, detachment, rotation, and movement of bacteria over the surface. An extensive hyphal network formed on the surface of the flow cell, protruding into the bulk flow, which subsequently detached. Multiple species mixed fungal-bacterial model biofilms were tested for isothiazolone biocide susceptibility. Biofilms were less susceptible to biocide treatment than planktonic cells of the same organisms. Mixed species biofilms, particularly for the bacterial species, offered greater protection against the action of the biocide compared to single species biofilms. Microbial loss as a result of biocide activity was shown by reduced cell surface coverage in electron micrographs.

Biofilms↗

PubMed1996

Video image analysis of hands: development of an 'anatomic index' as a potential outcome measure in rheumatoid arthritis.

In this study, we used video image analysis for the measurement of hand dimensions to reflect destructive changes in rheumatoid arthritis. Thirteen dimensions were measured from anteroposterior and lateral views of the hands, open and closed. Comparison of measurements in 19 patients and 19 control subjects showed significant differences for nine of the 13 measurements. Five were reproducible on retesting in a subset of patients and normals. Two were eliminated because they were similar to other measurements. The three remaining measurements selected for differentiation of patients and normals, and reproducibility, were combined in an arbitrary 'anatomic index'. This enhanced separation of normals and patients with rheumatoid arthritis. The results demonstrate that measurement of certain hand dimensions and their combination in an 'anatomic index' could provide a measure reflecting the progressive anatomical abnormality caused by rheumatoid arthritis. Validation of this concept could provide a further outcome measure in patients with rheumatoid arthritis.

Aged↗

PubMedDate not supplied

Changes in chromatin morphology after infection of mouse embryo fibroblasts with polyoma virus, detected by image analysis.

Nuclear chromatin properties in control, SV40-infected and polyoma-infected cultures of mouse embryo fibroblasts were studied using quantitative image analysis. Distribution of Feulgen-DNA-content per nucleus was found to be similar in all three groups of cultures. No differences in nuclear area, mean optical density of chromatin and area of chromatin at different optical density thresholds were measurable between control and SV40-infected fibroblasts. Polyoma-infected fibroblasts were found to have smaller nuclei, more dense and less homogeneous chromatin than non-infected cells. The changes of chromatin in polyoma-infected cells occur in G1, middle S and G2 nuclei. The results are interpreted as an early manifestation of the cytopathic effect of polyoma virus.

Animals↗