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PubMed1983

[In vitro decondensation of the human spermatozoan nucleus and image analysis].

Between the first stage: differentiation of the human spermatozoa from spermatid in testicle, and the second one: formation of male pronucleus in ovum, the nucleus of spermatozoa undergoes a chromatin condensation and a chromatin decondensation mechanism. Besides it is possible to get this decondensation mechanism in vitro by putting spermatozoa into specific solution with the purpose of carry out an image analysis. The aim of this study was to manage a quantitative analysis of the in vitro nuclear chromatin decondensation of human spermatozoa with an image analyzer of T.A.S. "texture analysis system".

Cell Nucleus↗
PubMed2006

"Clock-scan" protocol for image analysis.

Comparative analysis of extra- and intracellular distributions of protein markers in immunohistochemical and immunofluorescent studies relies on techniques of image analysis. Line or region of interest pixel intensity scans are methods routinely used. However, although having good spatial resolution, linear pixel intensity scans fail to produce integral image of the cellular distribution of the label. On the other hand, the regions of interest scans have good integrative capacity but low spatial resolution. In this work, we describe a "clock-scan" protocol that, when applied to convex objects (such as neuronal cell bodies and the majority of cells in culture), combines advantages and circumnavigates limitations of the above-mentioned techniques. The protocol 1) collects multiple radial pixel intensity profiles scanned from the cell center to the periphery, 2) scales these profiles according to the cell radius measured in the direction of the scan, and finally, 3) averages these individual profiles into one integral radial pixel intensity profile. Because of scaling, the mean pixel intensity profiles produced by the clock-scan protocol depend on neither the cell size nor, within reasonable limits, the cell shape. This allows direct comparison or, if required, averaging or subtraction of profiles of different cells. We have successfully tested the clock-scan protocol in experiments with immunostained dorsal root ganglion neurons. In addition, the protocol seems to be equally applicable for studies in a variety of other preparations.

Animals↗
PubMed1999

The prognostic significance of p53 expression quantitated by computerized image analysis in epithelial ovarian cancer.

The prognostic significance of p53 expression in 316 archival epithelial ovarian cancers was assessed using a static, computer-aided image analysis system (CAS 200). Using a 10% cut-off point, 26% of primary tumors and 35% of their metastases were positive for p53 protein. p53 positivity closely correlated with tumor grade (p < 0.001), stage (p < 0.001), residual tumor (p < 0.001), serous histologic type (p = 0.005), and tumor recurrence (p = 0.007). The overall 5-year survival was 37%. In univariate survival analysis, high grade, advanced stage, older age at diagnosis, and residual tumor > 2 cm were significant predictors of poor overall survival. In both the overall (p < 0.001) and recurrence-free (p < 0.001) survival, p53 immunopositivity predicted poor prognosis. p53 expression was a significant prognostic factor of multivariate recurrence-free survival (RR 1.93, p = 0.03), but not of overall multivariate survival. In addition, p53 positivity was a marker of poor overall survival in patients with well or moderately differentiated tumors, early stage tumors, or residual tumor. Quantitation of p53 immunoexpression by CAS may offer an objective means to identify patients who need more aggressive adjuvant therapy or new treatment strategies.

Adolescent↗
PubMed2000

In vivo comparison between computed tomography and magnetic resonance image analysis of the distal radius in the assessment of osteoporosis.

In a prospective case-control cross-sectional study, we investigated the usefulness of both computed tomography (CT) and magnetic resonance (MR) image analysis of the distal radius for distinguishing a small sample of fractured osteoporotic women from control women regardless of bone mineral density. The study population included 12 subjects who were divided into two groups according to their bone status. The first group consisted of six women with at least one vertebral fracture occurring in the absence of high-energy trauma, and the second group consisted of six women without disease affecting bone mass or bone metabolism. Cross-sectional and coronal slices were obtained from both CT and MR systems. For CT images, the slice thickness was 1000 jim and the plane resolution was approx 200 jim x 200 jim. MR images were obtained from a 1.5-T imager with a two-dimensional spin-echo Ti-weighted sequence leading to a slice thickness of 2000 jim and a plane resolution of 195 jim x 195 jim. Bone texture analysis was performed using fractal and structural methods leading to the measurement of 23 features. Most of the structural variables derived from histomorphometric parameters and were measured after segmentation from a binary or a skeletonized image. Bone densitometry was measured by dual-energy X-ray absorptiometry both at the lumbar spine and the nondominant femoral neck. On cross-sectional slices, 12 variables, mainly obtained from structural analysis, were significantly different between the two groups for CT images (p < 0.05) against two variables only for MR images (p < 0.05). The number of variables statistically different between the two groups was significantly higher for CT images compared with MR images (p = 0.003). In the same way, odds ratios for fracture per 1 control group standard deviation decrease were significant for 10 variables on CT images, whereas, in contrast, none of the variables measured on MRI images led to significant odds ratios. The results obtained for the two methods on coronal slices were poorer without a difference between either CT or MR images in terms of discrimination between fracture and nonfracture subjects. In conclusion, this study suggests that bone texture analysis obtained from CT compared with MRI offers a best discrimination between controls and osteoporotic patients, probably the result to the spatial resolution. which is better for CT than for MR images.

Absorptiometry, Photon↗
PubMed1998

Image analysis and pattern recognition for computer supported skin tumor diagnosis.

A new approach to computer supported recognition of melanoma and naevocytic naevi based on high resolution skin surface profiles is presented. Profiles are generated by sampling an area of 4 x 4 mm2 at a resolution of 125 sample points per mm with a laser profilometer at a vertical resolution of 0.1 micron. With image analysis algorithms Haralick's texture parameters, Fourier features and features based on fractal analysis are extracted. Genetic algorithms are employed successfully to select good feature subsets for the following classification process. As quality measure for feature subsets, the error rate of the nearest neighbor classifier estimated with the leaving-one-out method is used. Classification is performed with feed forward back-propagation network and the nearest neighbor classifier. Classification performance of the neural classifier is optimized using different topologies, learning parameters and pruning algorithms. The best neural classifier achieved an error rate of 4.5% and was found after network pruning. The best result with an error rate of 2.3% was obtained with the nearest neighbor classifier.

Algorithms↗
PubMed1998

Fast-FISH detection and semi-automated image analysis of numerical chromosome aberrations in hematological malignancies.

A new fluorescence in situ hybridization (FISH) technique called Fast-FISH in combination with semi-automated image analysis was applied to detect numerical aberrations of chromosomes 8 and 12 in interphase nuclei of peripheral blood lymphocytes and bone marrow cells from patients with acute myelogenous leukemia (AML) and chronic lymphocytic leukemia (CLL). Commercially available alpha-satellite DNA probes specific for the centromere regions of chromosome 8 and chromosome 12, respectively, were used. After application of the Fast-FISH protocol, and microscopic images of the fluorescence-labelled cell nuclei were recorded by the true color CCD camera Kappa CF 15 MC and evaluated quantitatively by computer analysis on a PC. These results were compared to results obtained from the same type of specimens using the same analysis system but with a standard FISH protocol. In addition, automated spot counting after both FISH techniques was compared to visual spot counting after standard FISH. A total number of about 3,000 cell nuclei was evaluated. For quantitative brightness parameters, a good correlation between standard FISH labelling and Fast-FISH was found. Automated spot counting after Fast-FISH coincided within a few percent to automated and visual spot counting after standard FISH. The examples shown indicate the reliability and reproducibility of Fast-FISH and its potential for automatized interphase cell diagnostics of numerical chromosome aberrations. Since the Fast-FISH technique requires a hybridization time as low as 1/20 of established standard FISH techniques, omitting most of the time consuming working steps in the protocol, it may contribute considerably to clinical diagnostics. This may especially be interesting in cases where an accurate result is required within a few hours.

Aneuploidy↗
PubMed1993

[The appliance of image analysis in the diagnosis of oral Lichen Planus and it's malignant change]

After the Feulgen dying,if the normal oral mucous,oral Lichen planus as well as the pathological cut sheets with atypical dysplasia and malignant change in defferent degrees,use the image analysis technique to measure the morphologic parameters of the nucleus(including nuclear surface area,perimeter maximum nuclear diameter,minimum nulear diameter,equivalent circle diameter,morphological factor) and the amount of DNA,5CER acts as an indes of distinguishing malignancy or benignancy,the value of 5CER in malignant is more than 10% and in benignant is less than 10%.The result of the analysis from the optical microscope differs from the optical microscope differs form the image analysis.There are so many personal factors in the qualitative analysis by optical microscope that it because quite imperative to research for a new diagnosing way.The synchronization of quantitative analysis and qualitative analysis can correct the personal errors in qualitative analysis.It will be very useful for directing the clinical practice and the judgment of prognosis.

Journal Article↗
PubMed1996

Immunocytochemical detection of regional protein changes in rat brain sections using computer-assisted image analysis.

We used several approaches to assess the reliability and sensitivity of computer-assisted densitometry to detect regional changes in tissue antigen content as a function of immunohistochemical staining density. We designed a model system to mimic variations in antigen concentration in postfixed, slide-mounted rat brain sections by varying the ratios of conjugated (biotinylated) to unconjugated secondary antibody. Antigen concentration was also varied in tissue discs made from mixing rat brain homogenate with increasing amounts of tissue embedding compound. The monoclonal antibody bd-17 to the beta2/3 subunit of the GABAA receptor was used as the primary antibody. Immunostaining density was visualized with diaminobenzidine (DAB). There was a significant, positive linear relationship (r = 0.97-0.99) between immunostaining intensity and antigen concentration. With this approach, changes in antigen content of less than 10%, as reflected in immunostaining intensity, were detectable in brain sections. The low degree of variability in measures of regional variation in immunostaining in sections from naive rats (n = 7) suggested that the method was suitable for quantitative analysis and indicated the reliability of the method. This systematic study of the utility of computer-assisted image analysis for semiquantitative immunohistochemical analysis found the method to be both reliable and sensitive.

Animals↗
PubMedDate not supplied

DNA ploidy and proliferating cell nuclear antigen image analysis of peritoneal and pleural effusions. A possible diagnostic role.

OBJECTIVE: To determine the role of DNA and proliferating cell nuclear antigen (PCNA) image analysis (IA) in enhancing the diagnostic sensitivity of conventional cytology (CC). STUDY DESIGN: The histopathologic and clinical data on 87 consecutive pleural and peritoneal effusions were used to evaluate the accuracy of CC and DNA IA results. RESULTS: CC showed a sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of 65%, 100%, 100% and 62%, respectively. Aneuploidy peaks were seen in 49 cases; 47 of them were true positives. Thirty of 38 diploid cases were true negatives. The sensitivity, specificity, PPV and NPV were 85%, 94%, 96% and 80%, respectively. There were positive correlations between DNA ploidy profile and PCNA proliferative index (PI), (R = .697) and significant differences in PCNA PI between malignant and benign effusions (P < .001). CONCLUSION: The DNA IA PI by PCNA can be used as a complementary diagnostic tool with CC in cytologically inconclusive cases.

Adult↗
PubMed2004

Sizing-up finite fluorescent particles with nanometer-scale precision by convolution and correlation image analysis.

Determining the positions, shapes and sizes of finite living particles such as bacteria, mitochondria or vesicles is of interest in many biological processes. In fluorescence microscopy, algorithms that can simultaneously localize such particles as a function of time and determine the parameters of their shapes and sizes at the nanometer scale are not yet available. Here we develop two such algorithms based on convolution and correlation image analysis that take into account the position, orientation, shape and size of the object being tracked, and we compare the precision of the two algorithms using computer simulations. We show that the precision of both algorithms strongly depends on the object's size. In cases where the diameter of the object is larger than about four to five times the beam waist radius, the convolution algorithm gives a better precision than the correlation algorithm (it leads to more precise parameters), while for smaller object diameters, the correlation algorithm gives superior precision. We apply the convolution algorithm to sequences of confocal laser scanning micrographs of immobile Escherichia coli bacteria, and show that the centroid, the front end, the rear end, the left border and the right border of a bacterium can be determined with a signal-to-noise-dependent precision down to approximately 5 nm.

Algorithms↗
PubMed1990

Image analysis and mathematical correlation between cell number and diameter of colonies in soft agar as a measurement of growth in soft agar.

Automated image analysis was used to measure the colony diameter and estimate the cell number in colonies under conditions for anchorage-independent growth (AIG). The calculated values for the number of AIG cells in a colony of a diameter greater than or equal to 60 microns were decidedly different from the actual values obtained by either automated or manual cell counting. Like animal cells that exhibit AIG, these colonies demonstrating anchorage independence can be enumerated reproducibly. However, the assumption is incorrect that the number of cells (N) in a colony expressing AIG varies directly with a change in the diameter of a colony (d). Whether one counts the number of cells manually in a colony of a definite diameter or arbitrarily uses a diameter function of greater than or equal to 60 microns as a linear distance that indicates the presence of 50 or more cells in a colony, each procedure has its own built-in bias. In procedures that require quantitative data, the most reliable procedure is to standardize the values for diameter of colonies with cell numbers in colonies.

Agar↗
PubMed1991

Quantitative image analysis with densitometry for immunohistochemistry and autoradiography of receptor binding sites--methodological considerations.

Major technical progress in the development of computer-based image analysis has made possible the entry of autoradiography and immunohistochemistry into a new era where quantification by densitometry has become easily accessible. Autoradiography could become quantitative and displayed adequate reproducibility with the help of emulsion-coated films and the use of scales of standards of known radioactivity exposed and analyzed in parallel to the tissue sections. Immunohistochemistry after revelation by a color-based enzymatic technique can also become quantitative, providing that standardization of the crucial steps of the procedure and calibration through a parallel treatment of a scale of antigen standards can be ensured. Such an approach is described here in the rat with reference to tyrosine hydroxylase (TH), the main synthesizing enzyme for catecholamines, and with dopamine (DA) itself, a catecholaminergic neurotransmitter. The different parts of the procedure, which can influence the results, such as the fixation of the animals by perfusion and the evaluation of the fluctuations via the calibration curve, are discussed in detail. Biological validation of the proposed procedure is described by reference to experiments already well documented biochemically, such as the induction effect of reserpine on TH in the rat locus coeruleus and the depleting effect of alpha-methyltyrosine (AMPT), a well-known blocker of TH activity, on rat striatal DA content. Finally the importance of restricting the measurements to the (pseudo)linear portion of the calibration curve is illustrated by the autoradiographic identification of the differential intrastriatal repartition of the dopaminergic D1 and D2 receptor sites, particularly the dual patch-matrix compartments.

Animals↗
PubMed1991

Digital image analysis of radio-opacities in the paranasal sinuses using computed radiography.

A computed radiograph system (Toshiba, model TCR-201) was used to investigate the digital image analysis of radio-opacity of the paranasal sinuses. The results of the preliminary phantom examination for evaluating the exposure technique indicated that the tube voltage should be kept constant. By using conventional radiographic images and tomographic images of normals and cases of sinusitis, the quantum values (Q-values), Q-value profiles, and Q-value histograms of radio-opacities in the paranasal sinuses were assessed statistically. Findings demonstrated that radio-opacities in the paranasal sinuses could be evaluated quantitatively by these digital image analyses.

Computer Systems↗
PubMed2003

Evaluation of the E+V video image analysis system as a predictor of pork carcass meat yield.

This study was conducted to assess the ability of the VCS2001 (E+V, Oranienburg, Germany) video image analysis system to predict pork carcass composition. Pork carcasses (n = 278) were selected from a commercial packing plant to differ in weight, Fat-O-Meater (FOM) predicted percentage lean, and gender. Carcasses were imaged three times with the VCS2001, chilled overnight, and then sequentially fabricated into boneless subprimals. The VCS2001 accurately predicted the weight of total saleable product (R2 = 0.88, root mean square error [RMSE] = 1.84) and fat-corrected lean (R2 = 0.92, RMSE = 1.66), but autocorrelation existed between dependent and independent variables. The VCS2001 was acceptably accurate and precise in predicting weights of bone-in ham (R2 = 0.83, RMSE = 0.80), bone-in loin (R2 = 0.74, RMSE = 1.17), loin lean (R2 = 0.77, RMSE = 0.82), belly (R2 = 0.78, RMSE = 0.94), sparerib (R2 = 0.55, RMSE = 0.28), and boneless shoulder (R2 = 0.73, RMSE = 0.79). Weights were more accurately predicted than yields (as a percentage of hot carcass weight) of total saleable product (R2 = 0.47, RMSE = 1.97) or total fat-corrected lean (R2 = 0.44, RMSE = 1.89) using VCS2002, and it did not accurately predict percentages of bone-in ham (R2 = 0.45, RMSE = 1.13), ham lean (R2 = 0.32, RMSE = 1.46), bone-in loin (R2 = 0.29, RMSE = 1.36), loin lean (R2 = 0.56, RMSE = 0.90), belly (R2 = 0.43, RMSE = 1.08), sparerib (R2 = 0.08, RMSE = 0.32), or boneless shoulder (R2 = 0.30, RMSE = 0.88). New prediction models and equations were developed using VCS2001 output variables plus hot carcass weight to predict weight of total saleable product (R2 = 0.89, RMSE = 1.72) and fat-corrected lean (R2 = 0.93, RMSE = 1.55) with very minimal increases in accuracy and precision over that achieved using E+V-programmed models and equations. Use of new prediction models and equations marginally improved accuracy and precision of estimations of total saleable product yield (R2 = 0.56, RMSE = 1.81) and fat-corrected lean yield (R2 = 0.57, RMSE = 1.67) over that achieved using E+V-programmed models and equations. The VCS2001 was not able to predict pork carcass composition more accurately than existing technology; therefore, further development is needed to assure commercial viability of this instrument.

Animals↗
PubMed2000

Bone wound healing after maxillary molar extraction in ovariectomized aged rats: quantitative backscattered electron image analysis.

The processes of bone wound healing after maxillary molar extraction in ovariectomized aged rats were examined by means of quantitative backscattered electron image analysis and energy-dispersive X-ray microanalysis. Six-month-old female rats were either sham-operated or underwent bilateral ovariectomy (OVX), and 60 days postoperatively, the maxillary first molars were extracted. On post-extraction days 7, 30, and 60, the dissected and resin-embedded maxillae were micromilled in the transverse direction through the extracted alveolar sockets, and new bone formation on the buccal maxillary bone surface and within the extracted alveolar sockets was examined. In both sham-operated control and OVX rats, new bone formation was recognized on the buccal bone surface, as well as within the extracted sockets, and increased daily through to day 60. In comparison to sham-operated controls, new bone formation in OVX rats was significantly decreased both on the buccal bone surface and within the extracted sockets. Our results suggest that bone wound healing by new bone formation after maxillary molar extraction is significantly decreased in OVX-induced osteoporosis.

Age Factors↗
PubMed2004

Transition of bacterial spatial organization in a biofilm monitored by FISH and subsequent image analysis.

The dynamic transition of bacterial community structure in a biofilm was monitored by the fluorescence in situ hybridization (FISH) technique and subsequent image analysis. Heterotrophic bacteria that had occupied the outer layer were gradually decreased whereas ammonia-oxidizing bacteria (AOB) gradually increased their growth activity and extended their existence area to the outer layer of the biofilm through the gradual reduction of the C/N ratio. The spatial organization of AOB in the biofilm dynamically changed responding to the environmental conditions such as pH fluctuation and lack of dissolved oxygen (DO) and had great influence on the nitrification activity. The accumulation of nitrite was observed at lower DO concentration, which might be due to the property that nitrite-oxidizing bacteria (NOB) possess of higher Km values for oxygen than AOB.

Bacteria↗
PubMed1977

[Comparative morphological studies of yeast cells using automated image analysis].

The ultrastructural alterations in cells of Candida utilis caused by the influence of copper ions have been studied by means of quantitative image analysis. A model has been proposed which presents the following informations: The main effect of the copper ions is represented by an increase of the volume of the whole cell and of that part of the cell which consists of nucleus, vacuoles, and inclusions (particles and globules). Nevertheless, neither the absolute volume of mitochondria, nor the density of mitochondria are influenced by high concentrations of copper ions in the culture medium.

Candida↗
PubMed1981

Macrophage adherence inhibition assay: measurements of adherent cells by the TV image analysis system Densitron.

A procedure is described to automate the cell counting step in the indirect macrophage adherence inhibition assay using the TV image analysis system Densitron. Comparison of the results of direct visual counting and of Densitron measurements of the adherent cells in the haemocytometer chamber indicates the qualification on principle of Densitron to substitute the time consuming and exerting visual counting procedure.

Animals↗