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At least 163 records · Page 9Linked to original sources
PubMed1997

[Cap image--a new kind of computer-assisted video image analysis system for dynamic capillary microscopy].

We describe a newly developed multi-function video image analysis system for the computer-aided evaluation of capillaroscopic findings in microcirculation research. The Cap image analysis system comprises an IBM-compatible PC with a Matrox image processing card and real-time video tape digitalization. The video recorder is driven by a personal computer to which it is connected via an RS-232 interface. In contrast to currently available systems, the program presented here makes it possible to select any of several integrated image analysis functions, depending on the quality of the video image. Some examples of the analysis functions available are measurements of erythrocyte flow velocity using the line shift diagram method, the spatial correlation method, and the auto flying spot method. The standard features of the new program include a number of special functions and automatic movement correction. The system thus makes it possible not only to measure numerous morphological parameters such as capillary diameter, length, torquation index and capillary density, but also to perform video densitometric analysis, for example using fluorescent dyes.

Blood Flow Velocity↗
PubMed1991

3-D image analysis system and megakaryocyte quantitation.

A quasi-automatic computer image analysis system has been developed for 3-D reconstruction of stained serial sections and implemented on an IBAS system. Some new automatic image analysis techniques have been designed and incorporated into the system. For image segmentation, a transition region determination based thresholding method is introduced. Neither histogram calculation nor empirical parameters are needed in the automatic threshold selection. A two step 3-D reconstruction procedure--symbolic and pictorial reconstructions--is designed to improve the flexibility and the computational capability of the system. The global level registration and local level registration are separated. The former consists of establishing the relationship among a large numbers of profile pairs dispersed in adjacent sections. A pattern matching method based on pattern recognition principles is devised to exploit the information about the statistical character of mismatch caused by deformation of sections and about the relationship of nearby objects. For the latter, an equivalent elliptical approximation method based on the physical theory of the rotation of rigid bodies is proposed. The system has been used for 3-D reconstruction and quantitation of megakaryocytes in human bone marrow tissue. Features about individual 3-D megakaryocyte cell and the spatial distribution of megakaryocytes are determined. The latter is a new contribution to megakaryocyte quantitation and is not possible by using conventional stereologic techniques. These experimental results have demonstrated the ability of the system to perform quantitative analysis.

Humans↗
PubMed2004

Enhanced speed and precision of measurement in a computer-assisted digital cephalometric analysis system.

The computer-assisted digital cephalometric analysis system (CADCAS) may reduce the time required for cephalometric analysis, especially for taking measurements. Aimed at estimating the time saved by using CADCAS, we measured the time needed by a clinician to perform the analysis in a traditional manner. We also sought to verify the accuracy achieved by traditional cephalometric analysis by exploring the disagreement between manual measurements and those generated by CADCAS. Our results revealed that, on average, even an experienced clinician needed more than 25 minutes to perform an entire cephalometric analysis using a traditional method, with more than 15 minutes of this needed just for taking measurements. Disagreements between measurements by traditional method and those by CADCAS were most frequently noted in the measurement value of cephalometric items reflecting the severity of a jaw discrepancy by the "sign" reflecting the anteroposterior relationship. After excluding the measurements with obvious error, the measurement differences between traditional method and CADCAS were not statistically significant in 23 of a total of 26 cephalometric items. In conclusion, the CADCAS can reduce the time needed for cephalometric analysis and can help reduce the human errors introduced during the manual-measuring procedure in the traditional cephalometric analysis.

Cephalometry↗
PubMed2004

Rapid and simple quantitative measurement of alpha-fetoprotein by combining immunochromatographic strip test and artificial neural network image analysis system.

BACKGROUND: Quantitative immunochromatographic strip (ICS) assay can facilitate clinical diagnosis by providing more information than traditional qualitative or semiquantitative strip assay. METHODS: We constructed a human serum alpha-fetoprotein (AFP) measurement system by combining semiquantitative ICS tests and artificial neural network (ANN) image analysis system [immunochromatographic strip analyzed by artificial neural network image analysis system (IAIS)]. After ICS tests completed, the AFP concentration can be obtained from analysis of IAIS software. The equipment required are commercial semiquantitative AFP dipstick, optical scanner, centrifuge (option), personal computer, and software of IAIS. RESULTS: The serum AFP concentrations measured by IAIS were strongly correlated (r = 0.9971) with that by RIA. Using Bland-Altman analysis, the IAIS achieved clinical acceptable limits of agreement in comparison with RIA. The within-run precision of IAIS, expressed as coefficients of variation (CV), at 81.7 ng/ml was 1.50% and, at 244.4 ng/ml, was 1.09%. The measurement of serum AFP by IAIS can be completed in 20 min. CONCLUSIONS: The newly constructed quantitative immunochromatographic strip assay (IAIS) is a simple, rapid, and reliable method for serum AFP measurement. With the simple equipment required, the IAIS can be performed outside the laboratory and is ideal for outpatient or point-of-care AFP testing.

Biomarkers, Tumor↗
PubMedDate not supplied

Computational systems analysis of developmental toxicity: design, development and implementation of a Birth Defects Systems Manager (BDSM).

Birth defects and developmental disabilities remain an important public health issue worldwide. With the availability of genomic sequences from a growing number of human and model organisms and the rapid expansion of the public repositories holding large-scale gene expression datasets, a computational systems analysis of developmental toxicology can incorporate this vast digital information toward the realization of predictive models for complex disease. Here we describe the initial design, development and implementation of a Birth Defects Systems Manager (BDSM). The project was motivated by the need for a computational-bioinformatics infrastructure to manage vast digital information from functional genomics and for a new knowledge environment specifically engineered for the analysis of developmental processes and toxicities. Proof-of-concept tested BDSM using meta-analysis of gene expression data collected from different laboratories, technology platforms, and study models. The composite dataset incorporated 232 microarray comparisons of RNA samples by single or dual microarray platforms, cDNA or oligonucleotide based probes, and human or mouse sequence information. Preliminary results identified system-level features in the embryonic transcriptome as it reacted to various developmental-teratological stimuli. BDSM is open access through the worldwide web (http://systemsanalysis.louisville.edu/) and can be integrated with other bioinformatics tools and resources to advance the pace of discovery in birth defects research.

Animals↗
PubMed2000

The use of the motion analysis system for evaluation of loss of movement in the finger.

We have used the motion analysis system to measure loss of finger movement after injury. The motion analysis system can provide information about the dynamic angular changes of each finger joint and the fingertip motion area for the injured finger. The latter can be used to calculate the percentage of fingertip motion area preserved. A stiff finger may show limited fingertip motion area with the finger joints tending to flex and extend together.

Adult↗
PubMed2006

A fully integrated microfluidic genetic analysis system with sample-in-answer-out capability.

We describe a microfluidic genetic analysis system that represents a previously undescribed integrated microfluidic device capable of accepting whole blood as a crude biological sample with the endpoint generation of a genetic profile. Upon loading the sample, the glass microfluidic genetic analysis system device carries out on-chip DNA purification and PCR-based amplification, followed by separation and detection in a manner that allows for microliter samples to be screened for infectious pathogens with sample-in-answer-out results in < 30 min. A single syringe pump delivers sample/reagents to the chip for nucleic acid purification from a biological sample. Elastomeric membrane valving isolates each distinct functional region of the device and, together with resistive flow, directs purified DNA and PCR reagents from the extraction domain into a 550-nl chamber for rapid target sequence PCR amplification. Repeated pressure-based injections of nanoliter aliquots of amplicon (along with the DNA sizing standard) allow electrophoretic separation and detection to provide DNA fragment size information. The presence of Bacillus anthracis (anthrax) in 750 nl of whole blood from living asymptomatic infected mice and of Bordetella pertussis in 1 microl of nasal aspirate from a patient suspected of having whooping cough are confirmed by the resultant genetic profile.

DNA↗
PubMed1991

A study of deoxyribonucleotide metabolism and its relation to DNA synthesis. Supercomputer simulation and model-system analysis.

A model system (1) was established to analyze purine and pyrimidine metabolism. This system has been expanded to include macrosimulation of DNA synthesis and the study of its regulation by terminal deoxynucleoside triphosphates (dNTPs) via a complex set of interactions. Computer experiments reveal that our model exhibits adequate and reasonable sensitivity in terms of dNTP pool levels and rates of DNA synthesis when inputs to the system are varied. These simulation experiments reveal that in order to achieve maximum DNA synthesis (in terms of purine metabolism), a proper balance is required in guanine and adenine input into this metabolic system. Excessive inputs will become inhibitory to DNA synthesis. In addition, studies are carried out on rates of DNA synthesis when various parameters are changed quantitatively. The current system is formulated by 110 differential equations.

Animals↗
PubMed1994

A statistical analysis system macro for age-standardized incidence rates.

The Statistical Analysis System (SAS) is a commercial software system for data analysis. We designed a SAS macro that produces age-specific rates of any given disease directly from the basic patient data on SAS files. The macro conforms to the statistical methods of the World Health Organization's MONICA project, which is a multinational project for MONItoring of trends and determinants in CArdiovascular disease. The data of the Coronary Register of the City of Turku, Finland, was used to test this macro. The data consists of both men and women between the ages of 35 and 64 years. Acute coronary events leading to hospitalization and acute coronary death events outside hospital have been registered since 1972. For age-standardization Segi's world population was used as the standard. The weights were then calculated for five consecutive years. Individual weights related to the population size of the reporting unit and the standard population were calculated for each subject in the population using the population size of the reporting unit and the standard population. This yielded the age-standardized rates of the acute myocardial infarction and the corresponding standard deviations. The macro permits standardization of the incidence rates of any disease. It will present the required figures instantly.

Adult↗
PubMed1984

Determination of gold and platinum traces in biological materials as a part of a multi-element radiochemical activation analysis system.

For the analysis of human tissues for traces of gold and platinum--being used as constituents of therapeutic agents--a radiochemical neutron activation method has been developed. The radiochemical separation involves the selective removal of radioactive gold--formed by the reaction 197Au (n, gamma)198Au and the reaction 198Pt (n, gamma) 199Pt ---- 199Au --as small metallic nuggets . The determination of gold and platinum is carried out as a part of an automated multi-element radiochemical separation scheme, allowing the determination of about 20 additional trace elements, and thus giving the possibility to study interelement relations. The analytical characteristics of the determination are evaluated. Gold and platinum levels measured in Bowen's Kale, NBS Bovine Liver and NBS Orchard Leaves are presented. Values are shown for gold, platinum, and 20 other trace elements in various healthy and cancerous tissues from patients treated with cis-platin. (Cis-Diamminedichloroplatinum II).

Activation Analysis↗
PubMed1994

[Accuracy and reproducibility of the Eyesys corneal topographic analysis system].

Corneal topographic analysis has become quite useful for corneal surgery. Quantitative data on the quality and accuracy of the available instruments are not well known. We studied the accuracy and the reproducibility of the Eyesys machine using 4 calibrated balls: 8.99 mm, 7.93 mm, 7.10 mm, 6.13 mm. The machine is accurate (precision less than 0.1D for all the balls) and reproducible (4 measurements) with a SD less than 0.05 diopter for all the balls except for the 55.04's ball (0.06 to 0.1). We also studied reproducibility with six normal corneas using the same method. SD was 0.26 diopter for keratometry and 0.50 diopter for the astigmatism value.

Astigmatism↗
PubMed2006

Micro analysis system for pH and protease activities with an integrated sample injection mechanism.

A micro analysis system for the electrochemical determination of the activity of protease along with pH sensing was fabricated aiming for its use in telemetric micro analysis systems targeting the testing of the stomach and intestines. The system consisted of a pH-sensing site and two protease assay sites formed in polydimethylsiloxane (PDMS) micro flow channels. To introduce sample solutions, valves were formed with gold electrodes in the inlets, which functioned on the basis of electrowetting. An external sample solution could be introduced into the sensing sites by switching on the valves at appropriate times. In the pH-sensing site, a pH-indicator electrode changed its electrode potential immediately after a sample solution reached an internal liquid-junction reference electrode. The slope of the calibration plot was -74.5 mVpH(-1). Bovine serum albumin (BSA) was used as the substrate for the enzyme and was spotted on the wall of the flow channel that faced the pH-indicator electrode of the protease assay sites. The release of protons accompanying the hydrolysis of BSA by the enzyme was detected using the pH-indicator electrode. When trypsin was contained in the sample solution as a test enzyme, a distinct decrease in pH, which was dependent on the trypsin activity, was observed, indicating that enzymatic hydrolysis was proceeding. The initial rate of potential change varied in proportion to the activity in a range between 1.0 and 51.7 Uml(-1). The integration of the microfluidic and sensing functions provides significant advantages for the use of this system as an isolated telemetric micro system that might operate with small batteries.

Biosensing Techniques↗
PubMed1995

Superimposed Image Analysis System (SIAS) software: a new approach to sperm motility assessment.

OBJECTIVE: To apply Superimposed Image Analysis System (SIAS) software (Delta Sistemi, Rome, Italy) to the objective analysis of sperm motility. DESIGN: To test a new procedure for sperm motility assessment based on image superimposition. RESULTS: The system can superimpose six sequential frames onto a monitor producing a final image with a motion effect similar to the multiple exposure photography method, but bypassing the film processing stage. Viewing the final image of a complete series of six superimposed frames allows the evaluation of the percentage of motile spermatozoa and their kinetic characteristics. Compared with multiple exposure photography, SIAS has the following main advantages: [1] the procedure is quick; [2] projecting the first frame alone allows the easy evaluation of sperm concentration; and [3] the system allows quick and easy analysis and measurement of each sperm trajectory frame by frame, thus avoiding misleading interpretations because of crossing sperm trajectories, collisions, and overlapping of motile spermatoza with round cells or immotile spermatozoa. CONCLUSIONS: Superimposed image analysis is a new approach to sperm motility assessment. It seems to be useful particularly in selected situations, such as oligozoospermia or in cases of increased round cell concentration. In these situations, SIAS can even serve as a support or an alternative to the computer-aided sperm analysis system widely used for objective sperm analysis.

Humans↗
PubMed1996

Comparison of different quantitative coronary analysis systems: ARTREK, CAAS, and CMS.

It has been known that the first generation quantitative coronary analysis systems overestimate small vessel sizes. In the 2nd generation the contour detection algorithms, e.g., of the new Cardiovascular Measurement System (CMS), were modified to correct for the limited resolution of the X-ray imaging chain. This study validated and compared the CMS with the well-known Coronary Angiography Analysis System (CAAS) and the vessel tracking program ARTREK in a phantom study and a clinical study. In addition, the influence of different acquisition media (cinefilm vs. digitally acquired angiograms) on the accuracy of quantitative analysis was examined. The phantom study comprised 19 stenotic or non-stenotic glass tubes with a diameter range from 0.54 mm to 4.9 mm. In the clinical study the mean diameters of 322 coronary segments were analysed and the results of the systems were compared among each other. The results of the phantom study were presented in terms of the mean difference (accuracy) between true and measured values. In the phantom study the overall accuracy of the CMS was -6 microns (ARTREK: 85 microns; CAAS: 35 microns) with an overestimation of small vessels of only -11 microns (ARTREK: 97 microns: CAAS: 51 microns). The clinical study showed that the CMS corrected the usually occurring overestimation of small coronary arteries and that the influence on the accuracy of different acquisition media is minor. Due to the modified algorithms the new CMS is able to measure coronary diameters down to 0.5 mm accurately. Therefore, the CMS seems to provide more precise measurements in quantitative analysis of small coronary diameters than CAAS and ARTREK.

Coronary Angiography↗
PubMedDate not supplied

Performance of an electrocardiographic analysis system: implications for pharmacodynamic studies.

The performance of a digital data-acquisition and -analysis system in measuring cardiac complex intervals was compared with manual measurements in 10 healthy subjects. A data set of 500 cardiac complexes was created from lead II electrocardiographic samples from each subject. Intervals were measured to the nearest 5 msec by hand and to the nearest 1 msec by the analysis system. Automated measurements of the RR interval and QRS duration exhibited no bias and median absolute errors of 3 msec. Measurements of the PR interval exhibited a significant bias (18 msec) that accounted for the majority of the imprecision (19 msec). A small but significant bias (4 msec) was found in the measurement of the QT duration with a median absolute error of 12 msec. The traditional method of averaging the values of 10 consecutive complexes provided results similar to individual complex measurements. The automated analysis of cardiac intervals can produce data that are suitable for pharmacodynamic studies.

Adult↗
PubMed2005

A new video image analysis system to study red blood cell dynamics and oxygenation in capillary networks.

OBJECTIVE: The authors present a Measurement and Analysis System for Capillary Oxygen Transport (MASCOT) to study red blood cell (RBC) dynamics and oxygenation in capillary networks. The system enables analysis of capillaries to study geometry and morphology and provides values for capillary parameters such as diameter and segment length. It also serves as an analysis tool for capillary RBC flow characteristics, including RBC velocity, lineal density, and supply rate. Furthermore, the system provides a means of determining the oxygen saturation of hemoglobin contained within RBCs, by analysis of synchronized videotapes containing images at two wavelengths, enabling the quantification of the oxygen content of individual RBCs. METHODS: Video recordings of RBC flow at two wavelengths, 420 nm (isosbestic) and 436 nm (oxygen sensitive), are made using a dual camera video microscopy system. The 420-nm recording is used to generate images based on the variance of light intensity fluctuations that help to identify capillaries in a given field of view that are in sharp focus and exhibit flow of individual RBCs separated by plasma gaps. A region of interest enclosing the desired capillary is defined and a fixed number of successive video frames at the two wavelengths are captured. Next a difference image is created, which delineates the RBC column, whose width is used to estimate the internal diameter of the capillary. The 420-nm images are also used to identify the location and centroid of each RBC within the capillary. A space-time image is generated to compute the average RBC velocity. Lineal density is calculated as the number of RBCs per unit length of a capillary segment. The mean optical density (OD) of each RBC is calculated at both wavelengths, and the average SO(2) for each cell is determined from OD(436)/OD(420). RESULTS AND CONCLUSIONS: MASCOT is a robust and flexible system that requires simple hardware, including a SGI workstation fitted with an audio-visual module, a VCR, and an oscilloscope. Since the new system provides information on an individual cell basis from entire capillary segments, the authors believe that results obtained using MASCOT will be more accurate than those obtained from previous systems. Due to its flexibility and ease of extension to other applications, MASCOT has the potential to be applied widely as an analysis tool for capillary oxygen transport measurements.

Animals↗
PubMed2002

[A gait analysis system based on digital video and digital image processing].

OBJECTIVE: To provide a gait analysis system. METHOD: The system is composed of general video devices and personal computer hardware. The techniques of digital video and digital image processing such as template matching, sub-pixel and motion estimate etc were employed to identify and trace the markers. RESULT: A gait result of a cerebral palsy object, which consists of bar-figure, data, and video was provided. CONCLUSION: The gait analysis system based on digital video and digital image processing is easy to use, and can provide visual result, which is easy to understand.

Cerebral Palsy↗