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At least 919 records · Page 51Linked to original sources
PubMed1999

Quantification of eosinophilic granule protein deposition in biopsies of inflammatory skin diseases by automated image analysis of highly sensitive immunostaining.

Eosinophilic granulocytes are major effector cells in inflammation. Extracellular deposition of toxic eosinophilic granule proteins (EGPs), but not the presence of intact eosinophils, is crucial for their functional effect in situ. As even recent morphometric approaches to quantify the involvement of eosinophils in inflammation have been only based on cell counting, we developed a new method for the cell-independent quantification of EGPs by image analysis of immunostaining. Highly sensitive, automated immunohistochemistry was done on paraffin sections of inflammatory skin diseases with 4 different primary antibodies against EGPs. Image analysis of immunostaining was performed by colour translation, linear combination and automated thresholding. Using strictly standardized protocols, the assay was proven to be specific and accurate concerning segmentation in 8916 fields of 520 sections, well reproducible in repeated measurements and reliable over 16 weeks observation time. The method may be valuable for the cell-independent segmentation of immunostaining in other applications as well.

Automation↗
PubMed1989

Image analysis of electron micrographs relating to mineralization in calcifying cartilage: theoretical considerations.

Biological mineralization kis a cell-mediated process which is believed to be triggered by a "nucleating agent." Various matrix structures, such as matrix vesicles, collagen fibrils and macromolecules, have been claimed to be the source of this substance, since these components have been found by transmission electron microscopy (TEM) of thin sections to be associated with early mineral crystals. Systematic image analysis of the relationships revealed in electron micrographs between specific matrix components and early mineral deposits has shown that unequivocal image interpretation is not possible. This is due principally to the problems posed by overprojection and truncation phenomena, since the structures being analyzed lie within the same dimensional range as thin section thickness. Various examples are illustrated and discussed. The site at which mineral crystals are initially laid down thus cannot be identified with any matrix structure using thin section TEM. Possible technical approaches to resolve this problem of image analysis are discussed.

Animals↗
PubMed2001

Computerized image analysis of bubbles in gastric aspirate for prediction of respiratory distress syndrome.

UNLABELLED: Gastric aspirates were obtained from 80 newborn babies (gestational age 24-34 wk). Fifteen of these babies developed respiratory distress syndrome (RDS). Bubbles were generated in the samples by vigorous suctioning and the number and size distribution of the bubbles were determined in random fields by computer-aided image analysis. Sensitivity and specificity for prediction of RDS were 87% and 78% for average diameter of bubbles (cut-off points >45 microm) and similar for the proportion and total number of microbubbles (diameter <20 microm). CONCLUSION: Computerized image analysis of bubbles in gastric aspirate can be used for non-biased prediction of RDS in newborn babies.

Gases↗
PubMed2002

Quantitative image analysis of drug-induced lung fibrosis using laser scanning confocal microscopy.

Pulmonary fibrosis is a serious lung disorder that in certain cases may be difficult to quantify. It was our objective to evaluate the use of laser scanning confocal microscopy (LSCM) in quantifying fibrosis after exposure to amiodarone (AD) and bleomycin (BLM), two commonly used therapeutic drugs known to cause debilitating lung fibrosis in humans. Male F344 rats were intratracheally dosed with AD (6.25 mg/kg on days 0 and 2), BLM (0.25 and 1.0 mg/kg on day 0), or their respective vehicle controls. The right lung was assayed for hydroxyproline, a biochemical measure of collagen, at day 21 for the BLM groups and day 28 for the AD groups. The left lung was fixed, sectioned into blocks, dehydrated, stained with Lucifer yellow (LY, 0.1 mg/ml), and embedded in Spurr resin. The area of lung tissue stained by LY was quantified by LSCM. A fibrotic response in the AD and BLM groups was confirmed by histopathological assessment and a significant increase (p < 0.05) in total right lung hydroxyproline above control values. The area of connective tissue stained by LY of the two drug-treated groups appeared as bright linear bands in the alveolar septae and was significantly increased (p < 0.05) as measured by image analysis when compared with their respective controls. LSCM, with its advanced image analysis system, is an alternate method to quantify fibrotic lung disease. LSCM could be particularly useful when tissue quantity is limited, such as when tissue has been archived from previous studies, or when analyzing human lung biopsy samples for disease diagnosis, where biochemical analysis is difficult.

Amiodarone↗
PubMed1991

Silver-stained structures in prostatic carcinoma: evaluation of diagnostic and prognostic relevance by automated image analysis.

The comparison of the diagnostic and prognostic significance of histology, immunohistochemical parameters (PSA, PSP), and silver-stained nucleolar organizer regions (AgNORs) was estimated in paraffin sections taken of 63 prostatic carcinomas prior to therapy. AgNORs were visualized with a one-step silver staining technique with the appropiate staining time determined by preliminary staining-time series. The mean AgNOR number per cell (n) and the mean AgNOR area per silver-stained dot (A) were determined by means of an automatic image analysis system. Thereby prostatic carcinomas exhibited multiple small AgNORs within their nuclei (n = 4.7, A = 0.09 micron 2), whereas benign prostatic epithelium showed few but large silver-stained particles (n = 1.8, A = 0.27 micron 2; p less than 0.001). This relationship was then calculated as a quotient of AgNOR number and area (NQ = n/A) which provided additional information for the diagnosis of malignancy as well as survival. Univariate survival analysis disclosed a set of four variables predicting death from prostatic cancer; cribriform growth pattern, AgNOR quotient, histological grade, and PSA immunoreactivity. Of these parameters, immunoreactivity of PSA failed to prove its prognostic significance in multivariate survival analysis (Cox model). No relation to prognosis was found for the number as well as the area of AgNORs alone. Therefore, image analysis proved to be a prerequisit for the feasibility of this promising technique by providing objective and reproducible results.

Acid Phosphatase↗
PubMed1982

The use of image analysis for estimation of growth in bone marrow cultures.

An image analysis system was used to assess growth in agar bone marrow cultures. The technique has advantages over visual counting techniques; it saves time, increases objectivity, reduces operator errors, and may be used to estimate total cell growth or mean clone size. Either measurement may be used to determine activity levels of factors that affect growth such as colony stimulating factors. The advantages and limitations of the technique will be discussed.

Agar↗
PubMed2005

Aging mechanisms of perfluorocarbon emulsions using image analysis.

The aging mechanisms of perfluorocarbon emulsions were investigated using image analysis. Oil-in-water emulsions of two perfluorocarbons, n-perfluorohexane and perfluorodecalin, were prepared with three emulsifiers, Lecithin, Span 20, and Pluronic F-68. The effect of the temperature and the replacement of water by an aqueous phase consisting of a microbial culture medium were also studied. The emulsions were prepared by sonication and their stability was followed through analysis of the evolution of mean droplet size. The results indicate that the stability of perfluorocarbon in water emulsions depends on all the parameters investigated and that two aging mechanisms, coalescence and molecular diffusion, may take place. Analysis of the evolution of the mean droplet size during long time periods indicate that coalescence is more common than previously reported for these systems and seems to be favored by a temperature increase.

Emulsifying Agents↗
PubMed1982

Simultaneous Feulgen densitometry and autoradiographic grain counting with the Quantimet 720D image-analysis system. II. Automated grain counting.

A Quantimet 720 Image-Analysis System has been configured and programmed to enumerate silver grains over labeled nuclei in Feulgen-stained autoradiographs. The accuracy and reproducibility of the estimates have been documented in 3H-thymidine (3HTdR)-labeled rat kidney cell cultures. The Quantimet and visual grain count estimates showed excellent correlation over a wide range of counts and was independent of grain density and clustering pattern. One advantage of this approach is that the grain counts can be related to specific cellular structures. The simultaneous measurement of the mean optical density of the grain-free nucleus provides a way of evaluating 3HTdR-absorption effects for valid grain count comparisons. Using a light pen, about 800 cells are measured per hour. The grain count estimates may be made simultaneously with estimates of Feulgen-stained DNA content in the labeled nuclei. This automated technology opens new avenues for critical applications to cell cycle analysis and related problems.

Animals↗
PubMed1997

AgNORs in estrogen-induced and lisuride- and thyreoidin-inhibited rat anterior pituitary hyperplasia. Computer image analysis and nonautomated AgNOR typing.

OBJECTIVE: A model of estrogen (E)-induced rat anterior pituitary hyperplasia blocked partly by thyroid hormones (estradiol plus thyreoidin [ET]) and nearly completely by lisuride (estradiol plus lisuride [EL]) and thyreoidin plus lisuride combination (estradiol plus thyreoidin plus lisuride [ETL]) was used to test a computer image analysis program, LUCIA, for argyrophilic nucleolar organizer region (AgNOR) evaluation. STUDY DESIGN: Nuclear and AgNOR area were measured in more than 700 cells in each experimental group. The nucleoli were also typed without the automated procedure. RESULTS: Mean nuclear area was significantly higher in E and lower in T. In all groups with blocked hyperplasia (ET, EL, ETL) the mean nuclear area was lower than in T. Mean AgNOR area was significantly higher in E but also, to a lesser extent, in T. The ET combination produced a partly diminished mean AgNOR area as compared to E; a severe reduction was observed in the EL and ETL groups. In nucleolar typing, thyreoidin, lisuride and their combination inhibited the increase in large nucleoli with finely dispersed AgNORs induced by estradiol. CONCLUSION: The LUCIA image analysis program for AgNOR evaluation proved able to monitor the slight changes in AgNORs in thyroid hormones- and lisuride-inhibited, estradiol-induced rat anterior pitutary hyperplasia.

Animals↗
PubMed1984

Karyometry by automated image analysis. Application to precancerous lesions.

Many works have shown a high frequency of increased nuclear DNA contents in various precancerous lesions. The true nuclear sizes, which are known to be well correlated with DNA values, may be stereologically estimated from nuclear profile data on tissue sections. Therefore, karyometry, which may be effected very efficiently by automated image analysis, offers an attractive choice when studying sections, in which photometric DNA evaluations are often unreliable. Prerequisites are Feulgen-stained slides and a stringent standardization of all histological procedures. Very few karyometric studies have been done on precancerous lesions. Automated image analysis has seldom been used for nuclear profile data gathering on sections. Suitable stereological models are necessary. The best-known are those for spherical nuclei, which allow an estimation of the size-distribution ('unfolding'). A specific model for parallel-oriented spheroids is particularly suitable for epithelial nuclei. It yields many stereological parameter estimations but does not yet allow a size-shape unfolding. We have used the model for parallel spheroids on nasal epithelial biopsies from nickel workers. The nuclear dimensions are usually clearly increased in metaplasia and dysplasia. Some rare dysplastic zones, however, present a major contribution of normal-sized nuclei, and this may have a prognostic significance. Our model may be applied to other epithelia. A new sphere unfolding model has been used on liver sections from Farber-protocol-treated rats. Compared to normal livers, where tetraploid nuclei predominate over diploid ones, transitional cell zones show an overwhelming predominance of diploid nuclei, and hyperplastic precancerous nodules have various degrees of non-modal and high-value ploidies. Karyometry may help to determine which lesions should be considered as possible premalignancies.

Animals↗
PubMed1994

Classification of red blood cells as normal, sickle, or other abnormal, using a single image analysis feature.

Sickle cell anemia is a disease for which there is currently no effective treatment. One method of evaluating clinical status is the counting of cell types based on morphology. There is a need for a rapid, reproducible method, superior to human inspection, for classification of these cells. Quantitative digital-image analysis is being applied to this need. Blood from 24 patients with sickle cell anemia (SS) and SC disease and ten hematologically normal volunteers (AA) was stressed by bubbling with nitrogen. One hundred fifty cells were analyzed from each sickle specimen, and 100 were analyzed from each nonsickle specimen. Expert observers classified each cell as normal (N), sickle (S), or other abnormal (A). Cells were analyzed with a custom, high-resolution image-analysis instrument. A total of 42 features including metric, optical density-derived, and textural features were extracted. The metric feature Form Factor (4 pi Area/Perimeter2) was selected by recursive partitioning analysis as the sole feature needed for segregating cells into the classes of N, A, and S. The agreement of automated classification (using cutpoints determined by recursive partitioning analysis) with a human expert for specimens from individuals with sickle cell anemia was 89% for N-, 73% for A-, and 92% for S-classified cells. For specimens from AA individuals, the agreement was 92% for N and 76% for A. For specimens from individuals with sickle cell anemia, rates of agreement between two human experts were compared and found to be 86% for N, 84% for A, and 80% for S. For specimens from AA individuals, the agreement was 90% for N and 87% for A.

Adolescent↗
PubMed1997

The application of image analysis and neural network technology to the study of large-cell liver-cell dysplasia and hepatocellular carcinoma.

Liver cell dysplasia (LCD) is considered a preneoplastic lesion, whose characterization and differentiation from hepatocellular carcinoma (HCC) and from the reactive changes seen in cirrhosis has been controversial. We studied 12 cases of LCD (large cell type) with image analysis techniques (IA) and compared the findings with those of HCC (n = 40), and a spectrum of non-neoplastic hepatic lesions including normal liver and cirrhosis (n = 49). A minimum of 200 Feulgen-stained nuclei were measured from each lesion with the CAS 200 image analysis system. The data were collected with the aid of CellSheet software. Thirty-four variables were measured, including geometric, textural, and photometric nuclear features and DNA ploidy. The data were analyzed with multivariate statistics and a backpropagation neural network (NN). Stepwise statistical analysis selected 22 variables that were statistically significant in the three groups with P values <.05. Various NN architectures were developed using these variables. The best NN architecture included a sigmoidal transfer function, 14 input, 16 hidden, and 3 output neurons. It trained to completion after 8,887 runs using 90% of the lesions. This NN yielded a 100% cross-validation rate for unknown cases. These data support the concept of LCD (large cell type) as a lesion that can be objectively distinguished from HCC and non-neoplastic liver. Our study also demonstrates the potential usefulness of IA for the evaluation of difficult histopathological problems.

Carcinoma, Hepatocellular↗
PubMed2005

Identification of novel mammalian growth regulatory factors by genome-scale quantitative image analysis.

Functional profiling technologies using arrayed collections of genome-scale siRNA and cDNA arrayed libraries enable the comprehensive global analysis of gene function. However, the current repertoire of high-throughput detection methodologies has limited the scope of cellular phenotypes that can be studied. In this report, we describe the systematic identification of mammalian growth-regulatory factors achieved through the integration of automated microscopy, pattern recognition analysis, and cell-based functional genomics. The effects of 7364 human and mouse proteins, encoded by individually arrayed cDNAs, upon proliferation and viability in U2OS osteosarcoma cells were evaluated in a live-cell, kinetic assay using quantitative image analysis. Overexpression of more than 86 cDNAs (1.15%) conferred dramatic increases in the proliferation, as determined cell enumeration. These included several known growth regulators, as well as previously uncharacterized ones (LRRK1, Ankrd25). In addition, novel functional roles for two genes (5033414D02Rik, 2810429O05Rik), now termed Gatp1 and Gatp2, respectively, were identified. Further analysis demonstrated that these encoded proteins promoted cellular proliferation and transformation in primary cells. Conversely, cells depleted for Gatp1 underwent apoptosis upon serum reduction, suggesting that Gatp1 is essential for cell survival under growth-factor-restricted conditions. Taken together, our findings offer new insight into the regulation of cellular growth and proliferation, and demonstrate the value and feasibility of assessing cellular phenotypes through genome-level computational image analysis.

Animals↗
PubMed1991

Quantification of vascular graft seeding by use of computer-assisted image analysis and genetically modified endothelial cells.

Current methods for the evaluation of retention of endothelial cells seeded on vascular grafts are limited by the inability to specifically identify and quantitate seeded cells on a long-term basis. To address this problem we developed a method of quantification of graft surface coverage using genetic labeling of endothelial cells combined with computer-assisted image analysis. Rabbit aortic endothelial cells were transduced with a marker gene (lac-Z) and seeded on polytetrafluoroethylene grafts. After histochemical staining in which the genetically labeled cells turn blue, computer-assisted image analysis was used to measure the percentage of graft surface covered by the seeded cells. The utility of the method was evaluated by using it to assess the effect on graft coverage of seeded cell density and by precoating with fibronectin. Quantification of surface area coverage was automated and reproducible both between scans and between observers. Use of this method allowed the determination of a linear correlation between cell density in the seeding suspension and graft coverage (r2 = 0.93, p less than 0.0001). The method also permitted confirmation of the positive contribution of fibronectin coating to graft coverage by seeded cells: 73% coverage coated versus 8% coverage uncoated (p less than 0.0001). The ability of this method to specifically identify genetically marked endothelial cells and their progeny makes it attractive for use in studies targeted at optimization of graft coverage in vivo.

Animals↗
PubMed1994

Image analysis of hemosiderin-laden macrophages in bronchoalveolar lavage fluid.

The aim of this study was to assess quantitatively the relationship between the number of iron-laden macrophages, extent of hemosiderin content and amount of dark-stained hemosiderin clumps in bronchoalveolar lavage (BAL) fluids. The series included specimens from 20 subjects whose BAL had yielded iron-laden macrophages. Six had developed hemoptysis 3-15 days prior to BAL. Quantitative studies were performed on smears stained by the ferrocyanide reaction, using true color image analysis for image segmentation. A top-hat function based on mathematical morphologic concepts was used for extraction of dark clumps of hemosiderin. The results demonstrated the presence of iron-laden macrophages three days after hemoptysis. There was a moderate correlation between the percentage of macrophages and amount of hemosiderin content, but the extent of dark-stained clumps did not increase in parallel to the increase in hemosiderin content and probably represented an advanced stage in the phagocytic processing of hemosiderin formed from engulfed red blood cells. The main difference between subjects with and without previous hemoptysis was higher values for dark clumps of hemosiderin in the former.

Adult↗
PubMed1999

Measurement of sarcomere length during fast contraction of muscle fibers by digital image analysis.

A low-cost, high-resolution (spatial and temporal) image analysis system was developed to measure sarcomere length (Sl) during fast twitch of isolated striated muscle fibers at different temperatures. Fiber images were examined during twitch with an imaging rate of 220 Hz. To increase temporal resolution beyond 220 Hz, consecutive temporally shifted image sequences (N sequences) were acquired. Individual or average Sl was directly measured from a horizontal profile without spatial-frequency assessment. Measurement precision (E) was determined and expressed as: E(%) = 100xPs/(IsxSl), where Ps is the pixel size and Is the involved sarcomere number. At 18 degrees C during isometric twitch, Sls were measured with 220 Hz temporal and 0.2% spatial resolutions. Sl shortened in the central region (0.21+/-0.12 microm) as tension developed, reaching a maximal shortening of 8.09 + 2.05% (at rest, Sl = 2.59+/-0.05 microm, n = 4) in 32.5+/-1.96 ms. At 30 degrees C, Sl variations were examined with 880 Hz temporal resolution, in which case maximal S1 shortening was reached in 15.74+/-1.99 ms, and then decreased to 5.19+/-1.97% (at rest, S1 = 2.6+/-0.06 microm). The twitch tension developed by the whole fiber was recorded and compared with sarcomere length behavior. Sarcomere length variations in the central region were representative of overall developed tensions at 18 and 30 degrees C.

Animals↗
PubMed1998

Early lens changes seen in patients with atopic dermatitis applying image analysis processing of Scheimpflug and specular microscopic images.

In order to know the initial lens changes that accompany atopic dermatitis (AD), 99 patients diagnosed dermatologically to have AD without any or with slight external ocular inflammations and with no habit of rubbing the eyelid due to severe itching were examined opthalmologically. Clinically, none of them showed any cataractous changes in their eyes. For the sake of comparison with the above population, 4 AD patients with cataractous eyes, 49 renal transplantation patients who were administered steroids over a long period of time but clinically had no cataractous lenses, and 94 healthy individuals with transparent lenses were also selected as subjects. The crystalline lenses of the subjects were examined using an anterior eye segment analysis system and specular microscopy. From Scheimpflug slit images of the lens, light scattering intensity of different lens layers was measured as an indicator of lens transparency changes. The subcapsular basement membrane and changes in the lens epithelial layers were analyzed from specular images of these areas by image processing. Results and considerations from the investigations were: (1) Initial lens changes in cases with AD which may be occult cataractous findings were often detectable. (2) Cataract associated with AD can be accelerated by steroid administration or the habit of strongly rubbing the eyelid, but this may not be the original cause of cataract formation. (3) Two types of cataract are seen in patients with AD: (a) anterior subcapsular plaque formation and (b) anterior and posterior subcapsular opacity formation. The latter type, however, is also accompanied by epithelial damage from the early stage. (4) Significant numbers of patients with AD who have not yet shown manifest lens changes were found among the subjects.

Adolescent↗
PubMed1985

Reproducibility of computer-aided image-analysis-derived estimates of the depth and area of radiolucencies in approximal enamel.

In vivo studies of caries progression from serial bite-wing radiographs require the reproducible detection and measurement of approximal radiolucencies in enamel; the aim of this study was to evaluate the reproducibility of a new computer-aided image analysis method. Three series of radiographs depicting natural caries lesions were employed: films of 11-12-year-old (Hounslow) schoolchildren, dental students from Hong Kong (HKDS), and extracted Hong Kong teeth (EXT). Each surface was "searched" three times, resulting in data from 450, 600, and 180 searches, respectively. Lesion detection was consistent for all but two of the 1230 searches. Average values for the standard error of the mean (SEM) of triple determinations of depth % were between 2.0 and 3.5%, while the mean SEM for area was from 0.03 to 0.04 mm2. Average test/re-test correlations ranged from 0.963 to 0.871 for depth and from 0.963 to 0.884 for area, while average reliability coefficients ranged from 0.937 to 0.821 for depth and 0.963 to 0.886 for area. There was a significant difference (P less than 0.001) between the reproducibility of the two clinical series, with measurements of the Hounslow lesions being more consistent. When compared with the reproducibility of attempts to grade radiolucency size visually, the image analysis method appears to offer considerable advantages, in that consistent estimates of radiolucency size are now possible. This method may facilitate more sensitive assessments of the behavior of lesions over time than has hitherto been possible.

Adult↗