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At least 73 records · Page 4Linked to original sources
PubMed1993

Comparison of the Bio Image Visage 2000 and the GELLAB-II two-dimensional electrophoresis image analysis systems.

To compare the Visage 2000 analysis system (Bio Image, Ann Arbor, MI, USA) with the GELLAB-II analysis system (National Cancer Institute, Frederick, MD, USA), we used each to perform image analysis of the same 29 silver-stained two-dimensional electrophoresis (2DE) gel image files from a study of urinary proteins in metal recovery plant workers who had confirmed body burdens of cadmium. Visage, aided by interactive analysis, detected an average of 890 +/- 177.6 spots per gel, or a total of 25,800 spots, whereas GELLAB-II detected 1971 +/- 198.5 spots per gel, or a total of 57,160 (a 222% increase over the Visage system), without operator intervention. Visage automatically quantified 52.5% (13,556) of the spots; 47.2% (12,173), consisting mostly of larger spots, had to be quantified interactively with an image editor, and 0.3% (71) were not quantified. GELLAB-II automatically quantified all detected spots. After we interactively assigned the maximum allowed number of landmarks (30 for Visage and 52 for GELLAB-II), we found that Visage matched 657 +/- 211.2 spots per gel, and GELLAB-II matched all detected spots and also extrapolated an average of 1269 virtual spots per gel. Plots of densities from the two systems on selected spots showed excellent agreement, and both systems showed high correlation between their measurements of the beta-2-microglobulin spot densities and an independent radioimmunoassay quantification of the original urine samples. By comparing the regression of the densities of all spots with urinary cadmium (UCD) levels, we found that several of the same detected spots from each system were highly correlated. The densities of four acidic proteins with relative molecular weights of approximately 112,000 Da (as quantified by GELLAB-II but not by Visage) were highly correlated with UCD concentrations. These proteins are new candidate biomarkers of cadmium toxicity. We compared the estimated labor costs of using each system to analyse a hypothetical 20-sample (60 gels) 2DE study and found that GELLAB-II was six times less expensive to use than Visage, primarily because of the operator time required to do interactive error correction with the Visage system.

Cadmium↗
PubMed2003

Microbiological quality of food in relation to hazard analysis systems and food hygiene training in UK catering and retail premises.

A meta-analysis of eight UK food studies was carried out to determine the microbiological quality of food and its relationship with the presence in food businesses of hazard analysis systems and food hygiene training. Of the 19,022 premises visited to collect food samples in these studies between 1997 and 2002, two thirds (66%) were catering premises and one third (34%) were retail premises. Comparison with PHLS Microbiological Guidelines revealed that significantly more ready-to-eat food samples from catering premises (20%; 2,511/12,703) were of unsatisfactory or unacceptable microbiological quality compared to samples from retail premises (12%; 1,039/8,462) (p < 0.00001). Three quarters (76%) of retail premises had hazard analysis systems in place compared with 59% of catering premises (p < 0.00001). In 87% of retail premises the manager had received some form of food hygiene training compared with 80% of catering premises (p < 0.00001). From premises where the manager had received no food hygiene training a greater proportion of samples were of unsatisfactory and unacceptable microbiological quality (20% retail, 27% catering) compared with premises where the manager had received food hygiene training (11% retail, 19% catering) (p < 0.00001). Where the manager of the premises had received food hygiene training, documented hazard analysis systems were more likely to be in place (p < 0.00001). Higher proportions of samples of unsatisfactory and unacceptable microbiological quality (17% retail, 22% catering) were from premises where there was no hazard analysis system in place compared to premises that had a documented hazard analysis system in place (10% retail, 18% catering) (p < 0.00001). Our meta-analysis suggests that the lower microbiological quality of ready-to-eat foods from catering premises compared with those collected from retail premises may reflect differences in management food hygiene training and the presence of a hazard analysis system. The importance of adequate training for food handlers and their managers as a pre-requisite for effective hazard analysis and critical control point (HACCP) based controls is therefore emphasised.

Allied Health Personnel↗
PubMed1991

Systems analysis applied to intracranial pressure waveforms and correlation with clinical status in head injured patients.

Intracranial pressure waveforms (ICPWF) in head injured patients vary with the nature and severity of injury. Clinical interpretation of ICPWF shape is not defined. Spectral analysis provides an objective method of measuring changes in waveform shape, but the indices most suitable for clinical use remain unknown. Spectral analysis has been applied to ICPWF recorded from 30 patients with head injury, classified on clinical grounds into good, poor and intermediate groups. Normalized indices derived from ratios of certain characteristics of the ICP waveform to those of the arterial pressure (AP) waveform, were different (P less than 0.05) in all groups. A simple index examined was the harmonic count ratio (Nc:Na) which decreased with increasing severity of injury. ICP/AP harmonic transfer functions were derived, and demonstrated a peaked response in the range 10-12 Hz. Increasing attenuation of this peaked response occurred with increasing severity of injury. These results suggest that transfer functions may be a clinically useful index of intracranial conditions.

Blood Pressure↗
PubMed1984

Consultant evaluation of a hospital medication system: analysis of the existing system.

A consultant team's evaluation of a system for distributing and controlling medications in a large teaching hospital is described. Through interviews with key personnel from administration, pharmacy, nursing, and the medical staff, an interdisciplinary research group identified problems in the reliability and response times of the hospital's existing medication system. After assessing staff expectations regarding acceptable standards for medication errors and response times and their attitudes toward proposed changes in the medication system, medication-error rates were determined using a pharmacist-observer method. Observations during 34 five-hour periods on four nursing units were conducted over a 17-day period. Medication-error rates were calculated as the frequency of medication errors during the observation period divided by the total opportunities for error (OE), which were defined as doses ordered plus unauthorized doses given. Response times for processing "now," "stat," and routine orders were also determined using work-sampling methods. The total medication-error rate for the nursing units studied was 9% excluding wrong-time errors; more than a third of doses were given more than 30 minutes before or after their scheduled administration times. Response times for "now" and "stat" orders averaged about 23 minutes, in conformance with the desired standard of 30 minutes. However, processing of routine orders required an average of two hours and seven minutes, much of which was attributed to delays in the messenger service. The basic design of the existing unit dose medication system contributed to problems in the reliability and efficiency of the system.

Attitude of Health Personnel↗
PubMed1981

Heart disease program for school children and high school students in Osaka City: an introduction of computer assisted ECG analysis system as a screening tool.

Fukuda ECP-100 computer assisted ECG analysis system was introduced into the heart disease program for school children and high school students in Osaka City in 1979. This analysis system was used as screening tool and 39,532 of 4th graders of primary schools were examined during the first year. To evaluate and improve this analysis system a "pilot study" was organized and 52 school physicians and 10 specialists made up a "working group". "Urgent reference codes" were set to be printed out so that the limitation of the present system of the Heart Disease Program should be compensated. Problems of the ECG analysis system were as follows. The Q wave registered too wide and there were same difficulties in recognizing the end point of the T wave. Recognition ot tiny "r" wave seemed to be impossible and base line sway seemed responsible for numerous erroneous outputs. Some cases corresponding to code "4-n-n" were found to be normal after further examination. This system can be said to be useful as a screening tool. Using this system at least 4 cases of serious lesion were newly detected, one case of myocarditis and 3 cases of myocardial diseases.

Adolescent↗
PubMed1992

Accuracy and precision of the corneal analysis system and the topographic modeling system.

Two computer-assisted topographic analysis systems were evaluated with calibrated spherical surfaces and normal human corneas. The Topographic Modeling System-1 (TMS-1) was found to be statistically more accurate in determining the power of calibrated spheres near the apex and at 1 mm from the apex than the Corneal Analysis System (CAS). The CAS, however, was statistically more accurate at 3 mm from the apex with each calibrated sphere. The small differences in accuracy between the two instruments, however, are unlikely to be of clinical significance. The topographic patterns on color-coded maps from 22 normal corneas of 11 subjects were similar with the two instruments. Simulated keratometry values with the CAS more accurately identified the keratometer-determined major cylinder axis compared with the TMS-1. Conversely, the TMS-1 was more accurate than the CAS at determining the level of corneal astigmatism.

Astigmatism↗
PubMed2002

Turbidimetric determination of chloride in different types of water using a single sequential injection analysis system.

A sequential injection analysis system for the turbidimetric determination of chloride in different types of water is proposed. The determination is based on the reaction of chloride with silver ions and the subsequent measurement of the turbidity caused by silver chloride precipitation. In this method, the use of toxic reagents, such as mercury thiocyanate, commonly employed in most spectrophotometric techniques for chloride determination, is avoided. The main feature of the developed system is the use of a single configuration to carry out the determination over a wide concentration range (2-400 mg L(-1)) by changing only the aspirated sample volume. This characteristic allows the determination of chloride in ground, surface and wastewaters using the same manifold. In addition, a considerable saving of precipitating reagent is achieved due to non-continuous consumption. The results obtained with the developed system were statistically indistinguishable from those of the potentiometric titration reference method. Relative standard deviations for ten consecutive injections were lower than 3.7%, with a sampling frequency of between 55 and 57 determinations per hour.

Chemical Precipitation↗
PubMedDate not supplied

The spinal cord development in guinea pig: a morphometric study on an image analysis system.

Using an image analysis system, the Authors carried out a morphometric study on guinea pig spinal cord in order to determine volumetric changes of white and gray matter during development. White and gray matter volumes were determined by measuring the area occupied by these matters in 10 micrograms sections of spinal cord in 1 day and 90 days old subjects. Several topographic correspondences in the localisation of the lowest and highest volumetric values were observed in the two groups of subjects. Such correspondences were more marked for white than gray matter. Moreover, during growth white matter volume showed an increase double that observed in gray matter.

Animals↗
PubMed1987

Quantitation of estrogen receptor content and Ki-67 staining in breast carcinoma by the microTICAS image analysis system.

The microTICAS image analysis system, originally designed for karyometry using Papanicolaou-stained or Feulgen-stained smears and tissue sections, has been adapted to assess tissue sections stained by immunohistochemical techniques. This system was used to quantitate growth fractions and the estrogen receptor (ER) content of breast carcinomas stained by immunoperoxidase techniques. The results were similar to those obtained with nonautomated methods of quantitating immunohistochemically stained tissue sections and, in the case of ER content, were similar to the results obtained with cytosol estrogen binding methods. The findings show that the microTICAS system provides an objective alternative to visual counting of labeled cells in tissue sections stained for growth fraction or for ER content by immunohistochemical methods.

Antibodies, Monoclonal↗
PubMed1984

[Systems analysis of pressure transmission in intracranial cavity].

Systems analysis of intracranial pressure pulse waveform was carried out in 6 dogs during normal condition (normocapnia and intracranial normotension) in order to explore how to transmit the pressure pulse through the intracranial cavity. Pulses originated in the heart travel in the intracranial cavity through the vessels, transmit into the cerebral tissue and finally reach to the dural surface. It can be speculated that the epidural pressure pulse waveform might be influenced by the property of intracranial components. The intracranial cavity which consists of brain parenchyma, vessels, cerebrospinal fluid, blood, pia, arachnoid, dura and skull is considered as a kind of system. The systems analysis method was applied to it. The common carotid arterial pressure pulse wave was used as the input signal of system, and the epidural pressure pulse wave was used as the output. The intracranial pressure was measured by an epidural pressure transducer attached to the dural surface through a parietal burr hole. The common carotid arterial pressure pulse wave and the epidural pressure pulse wave were recorded on FM analog tape. The characteristics of transmission are evaluated by the exact transfer function of system. We consider that the exact transfer function of system is obtained by the randomized input signal caused by the cardiac pacemaker or the aorta balloon. The power spectrum of input signal in this method didn't have a flat profile like completely random wave (or white noise) but a gentle slope between 1 Hz and 20 Hz. Therefore, the result in our method may be reliable only on the waves between 1 Hz and 20 Hz.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Quantitative analysis of dystrophin gene amplification products using a PC-based image analysis system.

A PC-based image analysis system for gel photographs of DNA gel patterns was developed. It was originally designed as a general-purpose, low-cost, yet high-performance system for wide applications in the biomedical area. In this study, we performed analysis of gel images obtained by polymerase chain reaction (PCR) amplification. The system employs a high-resolution CCD camera that can accurately measure grayness of the gel photographs for quantitative analysis of PCR products. The target DNA (exon 52 of the dystrophin gene), which had been found to be deleted in some patients with Duchenne/Becker muscular dystrophy (DMD/BMD), was amplified for the female family members together with the control DNA (exon 60) as a reference. The ratio of the target DNA to the control DNA was determined from PCR products to identify the carrier status of this disease by means of gene dosage. We conclude that 'the PC-based image analysis system' was useful for quantitative deletion analysis of DMD/BMD heterozygotes.

Adult↗
PubMed2003

Microchip-based chemical and biochemical analysis systems.

This review focuses on chemical and biochemical analysis systems using pressure-driven microfluidic devices or microchips. Liquid microspace in a microchip has several characteristic features, for example, short diffusion distances, high specific interfacial area and small heat capacity. These characteristics are the key to controlling micro unit operations and constructing new integrated chemical systems. By combining multiphase laminar flow and the micro unit operations, such as mixing, reaction, extraction and separation, continuous flow chemical processing systems are realized in the microchip format. By applying these concepts, several different analysis systems were successfully integrated on a microchip. In this paper, we introduce the microchip-based chemical systems for wet analysis of cobalt ion, multi-ion sensors, immunoassay, and cellular analysis.

Animals↗
PubMed1981

An evaluation of count rate losses due to dead time in static and mobile gamma camera data analysis systems.

The count rate responses of a gamma camera and data analysis system have been shown to behave as two separate components. Five systems made up of combinations of two static gamma cameras, two data analysis systems, and a mobile gamma camera system were investigated. Camera and data analysis system dead times are quoted and percentage corrections are plotted against radioactivity of 99 Tcm in a patient phantom within the field of view. It is recommended that such a detailed study should be performed for any gamma camera system as part of a quality assurance programme.

Gamma Rays↗
PubMed2005

Extension of x-ray imaging linear systems analysis to detectors with energy discrimination capability.

A figure of merit, the broad-spectrum generalized detective quantum efficiency, which describes the performance of digital detectors designed for broad-spectrum x-ray imaging is derived from linear response theory. This measure of the imaging efficacy of an x-ray sensor is obtained when detector contrast modulation in the domain of x-ray energy is introduced in the Fourier-based analysis of digital systems. A method is proposed to scale existing figures of merit according to the energy-dependent response of the detector and the spectral shape of the x-ray beam. The new figure of merit obtained with this method provides an extended description of system performance when comparing energy-integrating, single-photon counting, and future energy-sensitive x-ray imaging sensors. The applicability of this linear system analysis is restricted to the tasks of low-contrast object detection in radiography. The method for scaling the figure of merit to take into consideration broad-spectrum conditions is applied to mammography for future energy-dependent detectors. An approximation valid in the typical mammographic x-ray energy range is used to calculate the broad-spectrum generalized detective quantum efficiency at zero spatial frequency, for several mammographic x-ray spectra. X-ray energy weighting in mammography is investigated in the context of simulated tumors and microcalcifications detection by comparing this figure of merit, calculated for different detector technologies, under ideal imaging conditions, at zero spatial frequency.

Algorithms↗