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At least 1,351 records · Page 75Linked to original sources
PubMed2003

Computer-assisted image analysis to quantify daily growth rates of broiler chickens.

1. The objective was to investigate the possibility of detecting daily body weight changes of broiler chickens with computer-assisted image analysis. 2. The experiment included 50 broiler chickens reared under commercial conditions. Ten out of 50 chickens were randomly selected and video recorded (upper view) 18 times during the 42-d growing period. The number of surface and periphery pixels from the images was used to derive a relationship between body dimension and live weight. 3. The relative error in weight estimation, expressed in terms of the standard deviation of the residuals from image surface data was 10%, while it was found to be 15% for the image periphery data. 4. Image-processing systems could be developed to assist the farmer in making important management and marketing decisions.

Animals↗
PubMed2004

Development of image analysis techniques as a tool to detect and quantify morphological changes in anaerobic sludge: II. Application to a granule deterioration process triggered by contact with oleic acid.

Image analysis techniques are applied to monitor the morphological changes in granular sludge present in an expanded granular sludge blanket (EGSB) reactor fed with oleic acid. Deterioration of granular sludge was monitored along the trial period by measuring the percentage of aggregates smaller than 1 mm (in terms of Feret diameter) either in terms of projected area or in terms of number of aggregates. A good correlation was obtained between these values and the percentage of aggregates smaller than 1 mm were physically sorted and quantified by the volatile suspended solid content. The ratio of total filaments length to cross-sectional area of aggregates defined as LfA, was applied to quantify the dispersion level of the granular sludge, which increased until day 141 and remained almost invariant afterwards. LfA was sensitive to the sludge deterioration process and was able to indicate, with the anticipation of about 1 month, the most significant biomass washout episode that occurred in the trial period. A mechanism of filaments' release, detachment and selective washout was proposed to explain the action of LfA from this viewpoint. The equivalent diameter of the bottom aggregates larger than 1 mm increased with the increase on the amount of long chain fatty acids associated with the biomass by mechanisms of adsorption, precipitation, or entrapment. After a threshold value of about 200 mg COD-LCFA gVSS (COD = chemical oxygen demand; LCFA = long chain fatty acids; VSS = volatile suspended solids), a migration of granular sludge from the bottom to a top-floating layer was evident.

Anaerobiosis↗
PubMed1992

Immunostaining of cathepsin D in breast cancer: quantification by computerised image analysis and correlation with cytosolic assay.

Cathepsin-D (cath-D) was quantified in 34 breast cancer specimens by immunohistochemical staining of frozen sections with a computer image analysis and the results were compared with the corresponding cytosolic assay. Cath-D concentrations varied from 0 to 420 arbitrary units (AU). Tumour cells were more intensely stained than peritumoral tissue with the D7E3 mouse monoclonal antibody than with rabbit polyclonal antibodies. There was a good correlation (r = 0.80) between cath-D values obtained either by immunohistochemistry with D7E3 antibody or by cytosolic immunoenzymatic assay. However, with a cut-off of 50 AU, 3 out of 25 patients had higher immunohistochemical values and 2 had higher cytosolic values. Therefore, quantification of cath-D concentration in tissue section by immunostaining and a computerised image analyser, which is the only technique available for small tumours, should provide similar prognostic information to that obtained by assaying cath-D in the cytosol.

Animals↗
PubMed1996

An expert diagnostic system based on neural networks and image analysis techniques in the field of automated cytogenetics.

In this study, we introduce an expert system for intelligent chromosome recognition and classification based on artificial neural networks (ANN) and features obtained by automated image analysis techniques. A microscope equipped with a CCTV camera, integrated with an IBM-PC compatible computer environment including a frame grabber, is used for image data acquisition. Features of the chromosomes are obtained directly from the digital chromosome images. Two new algorithms for automated object detection and object skeletonizing constitute the basis of the feature extraction phase which constructs the components of the input vector to the ANN part of the system. This first version of our intelligent diagnostic system uses a trained unsupervised neural network structure and an original rule-based classification algorithm to find a karyotyped form of randomly distributed chromosomes over a complete metaphase. We investigate the effects of network parameters on the classification performance and discuss the adaptability and flexibility of the neural system in order to reach a structure giving an output including information about both structural and numerical abnormalities. Moreover, the classification performances of neural and rule-based system are compared for each class of chromosome.

Algorithms↗
PubMed1986

Application of automatic image analysis for morphometric studies of peroxisomes stained cytochemically for catalase. I. Electron-microscopic application.

The feasibility of the application of an electronic image analyzer, the Texture Analysis System (TAS) (Leitz Wetzlar, FRG), for fast automatic ultrastructural morphometric studies of hepatic peroxisomes has been investigated. Rat liver peroxisomes were stained selectively with the alkaline DAB procedure for localization of catalase in order to obtain sufficient contrast for automatic detection by TAS. Electron micrographs of ultrathin sections from this material were analyzed both automatically by TAS and manually by using a digitizer tablet connected with an Apple IIe microcomputer. The results showed negligible differences. As far as the speed of the operation is concerned, the image analysis was 4-5 times faster than the manual technique. In further studies, the importance of using DAB-stained sections for accurate morphometric studies of peroxisomes was demonstrated by comparing the results of such DAB-stained preparations with unstained material. This revealed that the numerical density was lower and the average profile diameter higher in unstained sections. The value for volume density was also affected, being about 30% lower in such preparations. It is likely that in unstained preparations small peroxisomes without crystalline nucleoids were frequently not identified as such and were not taken into account in morphometric calculations. These observations establish that computer-controlled electronic image analysis in conjunction with selective cytochemical staining of peroxisomes for catalase provides a fast, accurate and reliable method for ultrastructural morphometric studies of this organelle in rat liver.

Animals↗
PubMed1989

Mitogen-induced [Ca2+]i changes in individual human fibroblasts. Image analysis reveals asynchronous responses which are characteristic for different mitogens.

Temporal changes in intracellular free Ca2+ concentration ([Ca2+]i) in cultured human foreskin fibroblasts were investigated using image analysis techniques to simultaneously monitor Lys-bradykinin (BK)- or thrombin-induced elevations of [Ca2+]i in each individual cell within a microscopic field. Responses to BK are heterogeneous with respect to the shapes of the [Ca2+]i time courses. Furthermore, the onsets of these responses follow a variable lag period such that the individual cell responses occur asynchronously. The asynchrony and heterogeneity of individual cell responses are not related to cell cycle differences since noncycling cells respond in a similar manner. When cells are ranked according to order of an initial response to BK (the first cell to respond is ranked 1, the second to respond is 2, etc.), restimulation of the same cells with BK elicits a similar order of cell responses, and the shape of the [Ca2+]i time course of an individual cell is similar for both responses to BK. If cells that were stimulated with BK are washed and restimulated with thrombin (which produces [Ca2+]i changes similar to those induced by BK), the response order to thrombin does not correspond to the response order following BK stimulation. These data suggest that the asynchrony of [Ca2+]i changes induced by BK or thrombin is characteristic for each mitogen and may be determined by cell-to-cell variation in receptor number.

Benzofurans↗
PubMed1986

[Left axis deviation investigated by body surface mapping and phase image analysis].

Relationship between left axis deviation and left anterior fascicular block (LAFB) was investigated by estimating the ventricular excitation and contraction sequence using body surface potential mapping and phase image analysis by radionuclide ventriculography. This study included seven normal persons, eight patients with complete right bundle branch block (RBBB) without left axis deviation (LAD), twelve with RBBB and unblocked axis (determined by the first half of the QRS complex) of 0 degrees or farther deviated to the left (RBBB with LAD), and three with isolated LAD. The isochrone ventricular activation maps (VAT maps) were obtained by body surface mapping technique. Planar phase images in the left anterior oblique projection and short-axis ventricular tomographic phase images using a seven-pinhole collimator were constructed by ECG-gated equilibrium blood pool scintigrams. On the VAT maps of RBBB, there was a markedly delayed conduction to the right ventricle, however, in the left ventricle, the excitation was initiated in the anterior paraseptal region, and it proceeded rapidly toward the lateral and posterior walls, and in the same direction as normal. The VAT maps of RBBB with LAD were categorized in three types according to the activation sequence in the left ventricle. Type I, the same as maps of RBBB, consisted of three cases. Type II, four cases, showed excitation starting from the apex and ascending in the anterior wall. There were five cases of type III, which showed the earliest excitation in the basal posteroparaseptal region, proceeding toward the apex and ascending in the anterior wall. Type II was considered compatible with block of the left anterosuperior fascicle, and type III was that of left anterosuperior and midseptal fascicles. In types II and III, the phase delay in the left anterior wall was recognized in tomographic phase images, and the difference between right and left ventricular mean phase angles in planar phase images was significantly smaller than in cases of isolated RBBB, These were thought to support the existence of LAFB. The range of the unblocked axis of RBBB with LAD was -3 degrees approximately 13 degrees (-7.7 +/- 5.0 degrees) in type I, -8 degrees approximately -30 degrees (-19.8 +/- 9.1 degrees) in type II, and -33 degrees approximately -60 degrees (-51.0 +/- 10.9 degrees) in type III. All cases with left axis deviation beyond -30 degrees were of type III, and suspected to have extensive damage, including the midseptal fascicle.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1989

A quantitative 'in-situ' hybridization method using computer-assisted image analysis. Validation and measurement of atrial-natriuretic-factor mRNA in the rat heart.

We have validated a quantitative 'in-situ' hybridization method and computer-assisted image analysis of autoradiographs as a technique for measuring atrial-natriuretic-factor (ANF) mRNA in tissue sections of rat heart by: (i) producing radioactive standards to calibrate the autoradiograms and (ii) assessing: (a) specificity (through RNAase A background subtraction, comparison of ANF mRNA and non-ANF mRNA probe binding to sections, Northern analysis and section-thickness titration curves); (b) sensitivity (by calculating the limit of detection for ventricular levels of ANF mRNA); (c) precision [inter-assay CV (coefficient of variation) less than 10%; intra-assay CV 6-7%]; and (d) accuracy. We have found with this technique that deoxycortone and saline treatment of rats elevates ANF mRNA to a larger extent in the ventricles than in the atria and that, in neonatal-rat hearts, ANF mRNA is elevated in all cardiac chambers relative to adult levels.

Animals↗
PubMed1980

Polymorphonuclear motility: measurement by computer-linked image analysis.

Most methods of measuring neutrophil motility provide information mainly about the performance of a small proportion of the fastest moving cells. Application of a computer-linked image analysis technique, using the "Quantimet," provides a convenient, automated method of measuring the motility of the whole cell population. This makes it possible to test whether changes in motility represent a homogeneous alteration affecting all cells or a change in the numbers or performance of a subset of cells. In this study the neutrophils from patients with uncomplicated rheumatoid arthritis were found to perform similarly to normals, while cells from patients with Felty's syndrome were markedly slower. This was an overall, homogeneous slowing of the whole cell population, not due to a loss of fast moving cells.

Cell Movement↗
PubMed1983

Quantitative DNA determination by image analysis. II. Application to human and canine pulmonary cytology.

Comparative DNA measurements in human and canine preneoplastic and neoplastic tracheobronchial cells were made with the application of computerized image analysis. Canine studies demonstrated that the sequence of cellular events that precede epidermoid lung cancer simulates precisely the progression observed in humans. DNA studies concomitantly confirmed that there is a stepwise increase in DNA content with advancing nuclear atypia in metaplastic respiratory cells in both species. All carcinomas, regardless of histologic type, were significantly hyperploid to aneuploid (4c to 6c). Small-cell carcinoma exhibited a narrow modal distribution in the 4c region. The uniformity of the cytologic and quantitative DNA changes among these disparate species tends to confirm that humans and canines share biologic characteristics in bronchogenic carcinogenesis. The quantitative DNA measurements provide an objective cellular marker and may be used clinically for diagnostic purposes.

Adenocarcinoma↗
PubMed2003

Behavioural response of the cladoceran Daphnia magna STRAUS to sublethal Copper stress--validation by image analysis.

In this study changes in the locomotory behaviour of the freshwater cladoceran Daphnia magna STRAUS were used as sublethal indicators of toxic copper (Cu) stress. The behavioural responses were determined by a real time image analysis, using a video camera and a Pentium-PC equipped with a standard low cost frame grabber. For a sequence of 50 images per group, where 10 daphnids were moving simultaneously, the trajectories have been reconstructed in binary image sequences. As biological endpoints, we defined the average swimming velocity and the average duration of swimming activity and inactivity. The behavioural responses of the daphnids were analysed under normal conditions (without Cu stress) and after application of sublethal Cu stress of following concentrations (in microg l(-1) (ppb)): C1=1, C2=5, C3=10, C4=20, C5=30. The test organisms were exposed to the Cu concentration for 24 h under static conditions. Already after 9 h of Cu-exposure a significant (*P<0.05) decrease of the average swimming velocity could be observed at the group of the highest Cu concentration (30 ppb). After 13 h of Cu-contamination the swimming velocity was significantly (*P<0.05) reduced at group of 20 ppb Cu-treatment and after 14 h a significant (*P<0.05) decrease of the average swimming velocity could be measured at the group of 10 ppb Cu-treatment. No significant decrease of the swimming velocity could be observed in the 1 and 5 ppb Cu-treatment.

Analysis of Variance↗
PubMed2002

Comparative image analysis of cells in voided and catheterized urine.

OBJECTIVE: To objectively evaluate the difference in cytologic findings between specimens of voided and catheterized urine by using a comparative image analysis device, CAS200. STUDY DESIGN: Cells in voided and catheterized urine from 13 patients with transitional cell carcinoma (TCC), including 3 with grade 1, 6 with grade 2 and 4 with grade 3, were compared cytologically. The cellular area, nuclear area, nuclear/cytoplasmic ratio and nuclear density of both types of cytologic specimen were measured using CAS200. RESULTS: Cell area and nuclear area of grade 1 TCCs were significantly greater in voided urine than in catheterized urine. In contrast, cell area and nuclear area of grade 3 TCCs were significantly smaller in voided urine than in catheterized urine (P < .01), and nuclear density of grade 3 TCCs was higher in the latter than in the former. CONCLUSION: The cellular findings in voided urine were different from those in catheterized urine from the same patient. Thus, the method selected for obtaining urine specimens will affect the findings in urinary cytology.

Carcinoma, Transitional Cell↗
PubMed1989

A user-oriented software for cytological image analysis. Application to automatic DNA content measurement of thyroid cells.

More and more physicians and researchers in biology and image processing and analysis are using and developing methods which involve image analysing systems: image analysis permits replacement of qualitative subjective evaluation of cytological and histological specimens by quantitative methods. The purpose of our work was to provide a software which would fulfil constraints set by different users. This software is based on the following features: an automated cytology oriented architecture, a standard user interface and a selectable user mode. The system has been used to build a protocol for DNA content measurement on thyroid cells.

DNA, Neoplasm↗
PubMed2003

A computerized image analysis system for quantitative analysis of cells in histological brain sections.

We propose a reliable method for automatic counting of cells in brain sections labeled with different antibodies (against NeuN, parvalbumin, GABA and c-Fos) and in Nissl-staining. Images of stained sections are converted to binary images by thresholding. Clusters of 'ON pixels' (value of 1) corresponding to cell bodies are selected based on size. The parameters of the algorithm (intensity range and cluster-size) are adjusted for different methods of staining according to expert knowledge. The automatic cell counting method (ACCM) provides correct counting results, as demonstrated by a comparison of computational results with counts gained by human experimenters and with a commercially available image analysis system. On the basis of ACCM counts, small and perhaps physiologically relevant differences in the number of labeled cells can be revealed, as demonstrated here for the GABAergic system following electrical stimulation.

Algorithms↗
PubMed1983

Changes in the Paneth cell population of human small intestine assessed by image analysis of the secretory granule area.

Estimates of the Paneth cell population in human jejunum and ileum were made using measurement of the granule area in micron2 by image analysis in a defined number of crypts. This figure was preferable to granule area per mm as there was a significant difference in crypts per mm between biopsies and surgical samples. In the jejunum no significant difference was found between normal children and adults with and without peptic ulcer. In adults with subtotal or partial villous atrophy the decrease in area was not statistically significant and there was no decrease in area in children with partial villous atrophy and coeliac disease. There was a marked increase in granule area in the jejunum of patients who had had a previous partial gastrectomy which was statistically significant. In the ileum patients with carcinoma of the caecum had higher values than patients with non-inflammatory non-malignant conditions but this was not statistically significant and two patients with Crohn's disease had an increased granule area. Paneth cell populations are affected by alterations in the intestinal luminal environment due to previous surgery or neoplastic or inflammatory disease.

Adolescent↗
PubMed1975

[Quantitative image analysis as a scanning method in histopathological routine diagnostics applied for instance to chronical liver diseases (author's transl)].

A method is given by means of which histological image contents can quantitatively be determined with the help of electronic image analysis. A case of a chronical liver disease is quoted as instance for the application of the method in routine diagnosis. A possibility is shown to open quantitative and reproducible computation to descriptive histopathology.

Cell Nucleus↗
PubMed2003

[The relationship between the postmortem interval and the changes of DNA content in rabbit's cornea epithelial and endothelium by the computerized image analysis].

OBJECTIVE: To study the relationship between the postmortem interval (PMI) and the changes of DNA content in rabbit's cornea epithelial and endothelium. METHODS: Using the computerized image analysis to measure the DNA content in the cornea epithelial and endothelium of 105 rabbit's at every six hours during 72 hours after death. RESULTS: The degradation rate of DNA in nuclear has an apparent relationship in 72 hours after death of the rabbits. CONCLUSION: The determination of the quantity of DNA in cornea nuclear is a new method to estimate the PMI accurately.

Animals↗