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[Method of automatic recording and analysis of leukocyte migration based on the image analysis system].

The method of automatic registration and of the analysis of neutrophils' mobility with the use of the Image Analysis System is described in this paper. The authors developed an algorithm of cells identification which makes it possible to carry out cadre-by-cadre observing the shift of each cell's centre of gravity with the time interval between cadres more than 15 seconds. This algorithm also allows to measure areas, perimeters and orientation of cells and their changes. Looking after the shifts of the cells' centres of gravity allows to describe the cells' paths in the form of the following dependences: path-by-time, shift-by-time, angle of vector of shift alteration. Observing a great number of cells at the same time allows to get true statistical picture of neutrophils' activity and distribution of cells' activity in population of neutrophils during only some minutes of registration. It is shown that each cell in the population has its own constant velocity.

Algorithms↗

The development of a cervical smear preparation procedure from the BioPEPR image analysis system.

The preparation procedure for the BioPEPR automated image analysis system is described. Cervical cells are collected in a preservative solution and disaggregated by an automated syringing apparatus, giving about 50% single cells. After centrifugation, the preservative solution is discarded, 2% polyethyleneglycol in 50% ethanol (carbowax) is added, and the cell solution is automatically spread onto a glass slide, resulting in a cell density of about 50 cells/sq mm in the central area of the smear. Increasing cell density is shown to lead to a gradual linear decrease in single cells. All preparation steps have been critically evaluated, and the possibility of implementing this preparation procedure in a fully automated system is discussed.

Autoanalysis↗

Simultaneous five cell-lineage flow cytometric analysis system for detection of leucocyte antibodies.

Although flow cytometric (FCM) analysis is one of the most widely used approaches to screen the presence of leucocyte antibodies, it has several drawbacks. First, neutrophils and, especially, monocytes exhibit high background reactivity. Second, to determine antibody specificity, it is often necessary to examine not only neutrophils and monocytes but also other lineage cells including T cells, B cells and platelets. Therefore, we attempted to establish an FCM analysis system in which four lineages of leucocytes and platelets are simultaneously tested with low background. FCM analysis was performed using ethylene diamine tetraacetic acid-anticoagulated whole blood as cell sample without any cell preparation. Discrimination of five cell lineages was carried out based on the differences in forward vs. side scatter distribution and in the expression of CD4, CD20 and CD14. When anti-HNA (human neutrophil antigen) 1b antiserum was applied to HNA 1b-positive blood samples, only neutrophils were unambiguously positive. When anti-Naka (anti-CD36) antiserum was applied, only platelets and monocytes were positive. The background reactivity of neutrophils and monocytes was low enough. When anti-human leucocyte antigen (HLA) class II antiserum was tested, only B-lymphocytes and monocytes were positive. When anti-HLA class I antiserum was tested, all the five-lineage cells were positive.

Antibodies↗

Systems analysis of adverse drug events. ADE Prevention Study Group.

OBJECTIVE: To identify and evaluate the systems failures that underlie errors causing adverse drug events (ADEs) and potential ADEs. DESIGN: Systems analysis of events from a prospective cohort study. PARTICIPANTS: All admissions to 11 medical and surgical units in two tertiary care hospitals over a 6-month period. MAIN OUTCOME MEASURES: Errors, proximal causes, and systems failures. METHODS: Errors were detected by interviews of those involved. Errors were classified according to proximal cause and underlying systems failure by multidisciplinary teams of physicians, nurses, pharmacists, and systems analysts. RESULTS: During this period, 334 errors were detected as the causes of 264 preventable ADEs and potential ADEs. Sixteen major systems failures were identified as the underlying causes of the errors. The most common systems failure was in the dissemination of drug knowledge, particularly to physicians, accounting for 29% of the 334 errors. Inadequate availability of patient information, such as the results of laboratory tests, was associated with 18% of errors. Seven systems failures accounted for 78% of the errors; all could be improved by better information systems. CONCLUSIONS: Hospital personnel willingly participated in the detection and investigation of drug use errors and were able to identify underlying systems failures. The most common defects were in systems to disseminate knowledge about drugs and to make drug and patient information readily accessible at the time it is needed. Systems changes to improve dissemination and display of drug and patient data should make errors in the use of drugs less likely.

Boston↗

A new technique for the three-dimensional study of the spine in vitro and in vivo by using a motion-analysis system.

We introduce a new method with a motion-analysis system (MAS) to study the vertebral model in vitro. Compared with the currently most accurate technique, roentgen stereophotogrammetric analysis (RSA), the difference between the RSA and the MAS is 0.12 degree +/- 1.64 degrees. An accuracy with an error of 0.08 degree +/- 1.15 degrees is determined by means of an angle gauge. Although a significant difference between the MAS and the goniometer (p = 0.04) is found around the X-axis (theta; transverse plane), it is limited to < 1 degree. The MAS provides an in-depth insight into the mechanism of the three-dimensional rotation at each vertebra in vivo. The backward inclination of the apical vertebra (AV) and forward inclination of the upper-end vertebra (UEV) around the Y-axis (phi) results in a correction of the hypokyphosis shown by the Cobb angle in the sagittal plane. The clockwise rotation of the UEV in the Z-axis (psi) leads to a reduction of the Cobb angle in the frontal plane. Additionally, the MAS as an intraoperative alternative shows different results of the derotation maneuver by the Cotrel-Dubousset instrumentation (CDI) compared with the computed tomography (CT) scan. Our method gives more direct details of the derotation not influenced by patient posture, as observed in the CT scan.

Adolescent↗

Classification and counting of fluorescent pollen using an image analysis system.

Pollen viability is commonly assessed by fluorochromatic reaction (FCR) because of the high correlation between positive fluorescence of the pollen grains and their ability to germinate. One of the advantages of this method is its simplicity. An experiment to test FCR analysis for reproducibility, however, showed that results are affected by subjectivity. There is little consistency between analysts, and assessment by the same analyst may differ for the same pollen sample image examined at different times. These problems were solved by a computerized image analysis system that provides a method for classifying positive and negative fluorescent pollen and automatic counting of the grains in each class. The computerized image analysis system does not change the biochemistry of the FCR test, but avoids some experimental errors owing to the subjectivity of the analyst. Microscope images of the pollen after FCR were digitized and later analyzed by specially designed software, "Plant Meter." This software deletes the dark background of the image to isolate the grains, and subsequently counts positive and negative fluorescent pollen grains. An experiment was carried out to validate software output and it showed reliable results. Moreover, the software is user friendly and very little training is necessary for analysts to achieve reliable results.

Cell Count↗

[Design and application of biological rhythm automatic monitor and data analysis system].

OBJECTIVE: To design and develop a biological rhythm monitor and data analysis system for studying biological rhythm in animals under different conditions. METHODS: The system was a distributed digital control system consisting of a computer and zeitgeber generators. Acquisition of data on animal activity and generation of zeitgeber were modularized to meet the multiple requirements of experiment. System functions and animal adaptability to this system were detected by monitoring the rhythm of mouse activities under different light-dark cycles. RESULT: The animal experiment showed that the functions of this system, including data acquisition, data communication, light regulation and data analysis, were qualified for application. There was no apparent malfunction. CONCLUSION: The system is safe, reliable and easy to operate. The system could be a very useful system to study biological rhythm in animals.

Animals↗

The quantification of dental plaque using an image analysis system: reliability and validation.

AIM: Established clinical indices used to measure dental plaque have limitations. The aim of this study was to develop and evaluate a new method of quantitative plaque measurement, with increased sensitivity and reproducibility, using a purpose designed image analysis system. METHOD: After plaque disclosure, the patient was positioned in a cephalometric head holder mounted in a custom-built frame with standard lighting and camera position. A 32-bit Digital Camera grabbed the image of the patient's teeth, which was analysed using Adobe Photoshop (V5.02, Adobe Systems Ltd, Europe) and Image Pro Plus software (V4.0, Media Cybernetics, USA). Measurements were made on 120 incisors in 15 patients and reproducibility was assessed using Fliess' Coefficient of Reliability. Sensitivity was assessed by comparison of results of treatment effects from a clinical trial involving 30 patients. Analysis of covariance was used to compare the image analysis system with the Turesky modification of the Quigley and Hein plaque index and the Addy plaque area index. RESULTS: The results were within the 'Excellent Reliability' category, for inter-operator reproducibility and intra-operator repeatability. CONCLUSIONS: This new system provided accurate quantitative measurements of dental plaque and labial tooth surfaces and was shown to have increased sensitivity when compared with the Turesky modification of the Quigley and Hein plaque index and the Addy plaque area index. The stored images can be re-measured for reliability and comparability between studies.

Analysis of Variance↗

Dental caries in preschool Beijing and Connecticut children as described by a new caries analysis system.

A total of 625 children, 3-4 yr old, 426 from Connecticut Head Start programs and 199 from Beijing area nursery schools, were clinically examined for dental caries. Results were analyzed using the traditional dmfs index as well as a new "Caries Analysis System". This new system differentiated between caries patterns and examined the percentage of affected children (Prevalence), the degree to which these children were affected (Severity) and the proportion of total caries each disease pattern represented (Distribution). The Caries Analysis System revealed differences in caries experience and patterns among the racial/ethnic groups that the dmfs index did not. The Beijing children experienced the greatest Prevalence of all caries patterns; however, the Severity and Distribution of the caries patterns were similar to those of the Connecticut children. Within the group of Connecticut children, White children had the lowest Prevalence but the greatest Severity when compared with the Black and Hispanic children.

Child, Preschool↗

System analysis of patient management during the pre- and early clinical phase in severe head injury.

Head injury with or without polytrauma is the most important cause of death and severe morbidity in an age bracket of up to 45 years. Two major factors are determining its outcome, the extent and nature of the primary irreversible brain injury, and the subsequently developing manifestations of secondary brain damage, which in principle can be prevented by the management procedures and therapeutical interventions. Therefore, a better outcome from severe head injury depends exclusively on a higher efficiency of the management and treatment in order to inhibit secondary brain damage. In a novel nationwide research program on "Neurotraumatology and Neuropsychological Rehabilitation" sponsored by the Federal Government, the University of Munich in collaboration with the Max-Planck-Institute of Neurobiology, Martinsried, formed a research consortium with major city hospitals in Munich, Augsburg, Ingolstadt, Murnau, Vogtareuth, and the Southern Bavaria rural area, which are caring for neurotrauma patients with severe head- or spinal cord injury. Together with the corresponding rescue- and emergency organizations, such as the Red Cross, fire brigades, etc. the consortium is carrying out a system analysis as a joint venture on the organization, logistics, management, patient referral, etc. in severe head injury. The analysis includes the assessment of outcome-relevant time intervals of providing emergency care during the preclinical phase until admission of the patient to the hospital, until termination of the diagnostic procedures after hospital admission, and of the clinical management. The present findings and results are based on these comprehensive investigations by the study group in collaboration with more than 30 hospitals, institutions, organizations, and of more than forty physicians, students, and statisticians. In total 194 patients suspected to suffer from severe head injury were prospectively documented with onset of the assessment in the preclinical rescue phase. Confirmation of severe head injury according to a priori established selection criteria was obtained in 100 patients, the remaining number of cases was excluded. The protocol by purpose did not impose study-specific requirements outside of the routine procedures, which are established for the preclinical care and early hospital management. An exception, however, was to collect arterial blood samples, if possible prior to intubation and ventilation, or administration of O2, in order to obtain early information on the acute respiratory state as a potential risk factor of the outcome. Arterial blood samples could be collected in 60 cases at the scene, in no less than 37 patients prior to intubation and ventilation. The data collected during the prehospital and early clinical phase on the temporal course of these patients provide valuable information with unmatched accuracy for evaluation of the management efficiency of the rescue system, transportation, and the clinical care. In conclusion, the prospective system analysis on the organization and management of patients with severe head injury is the first study of this type carried out in Germany. Due to the specific efforts of quasi on-line documentation of the patients' state and course of events, beginning at the scene of an accident and covering the first days at the hospital, data of high quality were obtained. The data flow during the investigation was maintained among others by regular conferences of the Study Group including the crew of documentation assistants at regular intervals. The presently reported phase-1 study was concluded in October 1997. It is followed by a phase-2 study with the attempt to collect prehospital- and early clinical management and care data in the catchment area on an epidemiological basis. (ABSTRACT TRUNCATED)

Craniocerebral Trauma↗

Comparison of fundamental frequency and perturbation measurements among three analysis systems.

The need for standardization of procedures in approaches to voice measurement has been recently emphasized. The purpose of this study was to determine the extent to which the acoustic perturbation measurements from three different analysis systems agree when standardized recording and analysis procedures are used. High-quality acoustic voice recordings from 20 patients were analyzed. The results showed that, although fundamental frequency measurements were in strong agreement among the three systems tested, frequency and amplitude perturbation measurements were not in agreement. The underlying approaches to perturbation measurement appeared to be sufficiently different to produce different results. An argument is made for a standardized set of acoustic signals representing normal, dysphonic, and synthesized voices with known characteristics to facilitate testing of new acoustic analysis systems and confirm measurement accuracy and sensitivity.

Adolescent↗

Comparison of normal sperm morphology outcomes from two different computer-assisted semen analysis systems.

By eliminating the human evaluation variable, it was possible to carry out an investigation into the 'true' association between normal sperm morphology outcomes assessed according to the World Health Organization guidelines and strict criteria. Two computer-assisted semen analysis systems were used, IVOS and Mika, to evaluate Diff-Quik and Papanicolaou stained slides. As expected, the mean normal sperm morphology outcomes for the World Health Organization classification evaluations were markedly higher for both the Diff-Quik (mean difference = 40.13%) and the Papanicolaou (mean difference = 32.55%) stained slides. The association between the outcomes were low for the Diff-Quik stained slides (r = 0.379) and poor for the Papanicolaou stained slides (r = 0.110). While the association achieved with the computer-assisted semen analysis systems using Diff-Quik stained slides was comparable to the association between the manual evaluations (r = 0.386), the manual evaluation of Papanicolaou stained slides produced a relatively good association (r = 0.690). Although the numbers were small, the results show the probability of poor class correlations. Approximately 40% of outcomes were incorrectly classed at a 14% (strict criteria) and 50% (World Health Organization guidelines) cut-off point for both staining methods. This study confirms the fundamental differences between the two classification systems. The results also indicate that, of the two stains used, Diff-Quik should be the preferred staining method for computer-assisted sperm morphology evaluations.

Autoanalysis↗

Simple sequential injection analysis systems with a dynamic surface tension detector.

Simple sequential injection analysis systems with DSTD (SIA/DSTD) have been developed. One was employed for the study of the effects of the ion contents in solutions to the dynamic surface pressure of ionic surfactants. The results from the studies show the possibility for an alternative simple fast screening, but also a sensitive procedure for water quality determination. Another simple SIA/DSTD system has been demonstrated for the quantification of an anionic surfactant using a single standard calibration.

Calibration↗

Comparison of EEG between nasopharyngeal and scalp leads with the aid of an automatic EEG analysis system.

We analyzed the EEG quantitatively with an automatic EEG analysis system, and introduced this system for investigation the relationship between the scalp EEG and nasopharyngeal EEG. The EEG was recorded from healthy volunteers by photic stimulation. We found that components of slow waves like delta and theta were more rich but alpha component was less in the nasopharyngeal EEG than in the scalp EEG. In the analysis of the rate of the appearance of each EEG wave using photic stimulus, a decrease of alpha 1 and an increase of theta 1 are observed in the scalp EEG while there are no specific changes of them in the nasopharyngeal and scalp EEGs. The nasopharyngeal EEG obtained from the vicinity of the base of the brain was thought to originate from the vicinity of the brain stem.

Adult↗

A profile of communication in primary care physician telephone consultations: application of the Roter Interaction Analysis System.

BACKGROUND: Telephone consultations are a part of everyday practice, there is surprisingly little research on the subject. AIM: To describe the variation of consulting skills within a body of telephone consultations in primary care, highlighting the performance of one method of assessing the process of the consultation-- the Roter Interaction Analysis System-- with telephone consultations. DESIGN OF STUDY: Cross sectional study of 43 recordings of telephone consultations with GPs. SETTING: One rural county in the Midlands. METHOD: Recordings were made of 8 GPs, purposively selected for maximum variance in one region of the UK. Forty-three consultations were coded using the Roter Interaction Analysis System. From the descriptive categories, six composite categories were compiled reflecting a number of domains of interaction in a consultation: rapport, data gathering, patient education and counselling, partnership building, doctor dominance and patient-centredness. Analysis of variance was undertaken to explain variations between consultations for the different domains. Comparison was made to findings from similar work for face-to-face consultations. RESULTS: These telephone consultations feature more biomedical information exchange than psychosocial or affective communication. Length of interaction accounts for much of the variation seen between consultations in the domains of rapport, data gathering, patient education and counselling and partnership. Male doctors are more patient centred in this study. There is the suggestion of more doctor dominance and a less patient-centred approach when comparisons are made with previous work on face-to-face consultations. CONCLUSIONS: Although the telephone is increasingly being used to provide care, this study highlights the fact that telephone consultations cannot be taken as equivalent to those conducted face to face. More work needs to be done to delineate the features of telephone consultations.

Adult↗

A new semi-automated chromosome analysis system for in vitro chromosomal aberration tests.

We have evaluated a new semi-automated chromosome analysis system, employing the Magiscan human metaphase finder, for in vitro chromosomal aberration tests. The metaphases on a slide are recognized using the main system, a metaphase finder, and their stage coordinates are transferred to the satellite system, a computerized microscope with a motorized stage, by way of a diskette. In the satellite system, a researcher analyzes one metaphase after another at high power (100 x objective) without changing the objective. The effectiveness of the system, in comparison with the manual metaphase finding and analysis, was confirmed in in vitro chromosomal aberration tests using cultured Chinese hamster cells. Structural or numerical aberrations in the cells did not affect the metaphase findings. The system reduces the time for chromosome analysis by a factor of about 4. Moreover, the system provides perfect reproducibility for analyzing procedure. It is concluded that this semi-automated system is useful in in vitro chromosomal aberration tests.

Animals↗

A new digital image analysis system useful for surface assessment of vitiligo lesions in transplantation studies.

So far there is no uniformity in the evaluation methods used in the assessment of treatment outcome in vitiligo studies. The ability to objectively measure surfaces of vitiligo lesions is important for both clinical practice and research. Our objective was to assess the reproducibility, accuracy, user-friendliness and time effectiveness of a new digital image analysis system for surface measurement of vitiligo lesions. Three different observers performed both a visual estimation and a digital image analysis on 30 images of 10 vitiligo lesions. Inter- and intra-observer variation were evaluated and results were compared with the 2D gold standard measurements and a 3D measurement. A high inter- and intra-observer variability was observed for the visual estimation of surfaces. With the digital image analysis system a significant improvement of the reproducibility was achieved (p = 0.01). Moreover, results were accurate and the measurement procedure was user-friendly. Importantly, a systematic underestimation was demonstrated when comparing the 2D with the 3D measurements. We introduced an objective measurement method that might be useful in the future for consistently measuring surfaces of selected vitiligo lesions both before and after different therapeutic modalities.

Adolescent↗

Technical note: validation of a motion analysis system for measuring the relative motion of the intermediate component of a tripolar total hip arthroplasty prosthesis.

Tripolar total hip arthroplasty (THA) prosthesis had been suggested as a method to reduce the occurrence of hip dislocation and microseparation. Precisely measuring the motion of the intermediate component in vitro would provide fundamental knowledge for understanding its mechanism. The present study validates the accuracy and repeatability of a three-dimensional motion analysis system to quantitatively measure the relative motion of the intermediate component of tripolar total hip arthroplasty prostheses. Static and dynamic validations of the system were made by comparing the measurement to that of a potentiometer. Differences between the mean system-calculated angle and the angle measured by the potentiometer were within +/-1 degrees . The mean within-trial variability was less than 1 degrees . The mean slope was 0.9-1.02 for different angular velocities. The dynamic noise was within 1 degrees . The system was then applied to measure the relative motion of an eccentric THA prosthesis. The study shows that this motion analysis system provides an accurate and practical method for measuring the relative motion of the tripolar THA prosthesis in vitro, a necessary first step towards the understanding of its in vivo kinematics.

Algorithms↗