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At least 577 records · Page 32Linked to original sources
PubMed2005

Phenotypic analysis of adults and eggs of Fasciola hepatica by computer image analysis system.

Knowledge of the morphological phenotypes of the liver fluke Fasciola hepatica (Trematoda: Digenea) is analysed. The influence of parasite age on its dimensions, the adult fluke growth model, variation in a biometric variable versus time, and variation in a biometric variable versus another biometric variable (allometric model) are revised. The most useful allometric model appears to be (y2 m-y2)/y2=c [(y1 m-y1)/y1](b), where y1=body area or body length, y2=one of the measurements analysed, y1 m, y2 m=maximum values towards which y1 and y2, respectively, tend, and c, b=constants. A method based on material standardization, the measurement proposal and allometric analysis is detailed. A computer image analysis system (CIAS), which includes a colour video-camera connected to a stereomicroscope (for adult studies) and a microscope (for egg studies), facilitates the processing of digital imaging. Examples of its application for the analysis of the influence of different factors on the liver fluke phenotype are shown using material from the Northern Bolivian Altiplano, where human and domestic animal fascioliasis is caused by F. hepatica only. Comparisons between the development of livestock fluke populations from highlands and lowlands are discussed and the relationships between host species and liver fluke morphometric patterns is analysed.

Altitude↗
PubMed2003

Biosensors for the determination of ortho-acetyl-L-carnitine. Their utilization as detectors in a sequential injection analysis system.

In order to determine ortho-acetyl-L-carnitine, two biosensors were proposed. The biosensors were designed using physical immobilization of L-amino acid oxidase (L-AAOD) and horseradish peroxidase (HRP). Electrode characteristics were obtained and compared for the two carbon paste (graphite powder and paraffin oil) biosensors. The linear concentration ranges for the proposed biosensors were in the ranges of fmol/L to nmol/L, magnitude order with low limits of detection. Due to their reliability, the biosensors were used as detectors in a sequential injection analysis system, and gave reliable results for on-line assay of ortho-acetyl-L-carnitine in synthesis process control with a frequency of 75 samples per hour.

Acetylcarnitine↗
PubMed2005

[Developmental changes in the Collis horizontal reaction analyzed using a three-dimensional video motion analysis system. II. Examination of upper-limb movement during the Collis horizontal reaction].

At four months old, infants of 72% challenged with the Collis horizontal reaction touch the floor with the back of their free hand. As the infants grow older, the ratio of infants that open their free hand and perform a support reaction increases from 0% to 100%. At nine months old, all infants perform this support reaction with their free hand palm-side down. To assess infant development more accurately, we used a three-dimensional video motion analysis system to evaluate upper limb movement in 38 infants (total 151 times) from 4-9 months old during the second and third phases determined by the Collis horizontal reaction. By analyzing the constituent components of upper limb movement during the Collis horizontal reaction, we assessed the usefulness of the reactions as an objective tool to measure developmental changes in infants. During the analysis, we thought to assess the speed of the upper limb reaction was respect to pronating the forearm, supporting the body with the palm down, and location of their free hand. The analysis shows that if development progresses normally and infants pronate the forearm to support the body with the palm down, the central value at which their free hand is located moves to a point under the shoulder. The results suggest that in infants four to nine months old, the Collis horizontal reaction is an excellent method to assess not only the present physical development level, but also future physical development attainment by only evaluating developmental changes of upper limb movement only.

Child Development↗
PubMed1990

SMRFIT: a Statistical Analysis System (SAS) program for standardized mortality ratio analyses and Poisson regression model fits in community disease cluster investigations.

Increasingly, health departments are being pressed by the public to respond to disease risk with cluster investigations in communities and neighborhoods. This is a direct result of growing concern about the role that the environment may play in disease risk. While extensive analyses directly inputing exposures or numbers at risk are often necessary to thoroughly investigate clusters, it is quite useful to perform an exploratory analysis with existing morbidity and mortality data as a first level of response. To meet this need for timely evaluation, the authors describe a user-friendly Statistical Analysis System (SAS) program called SMRFIT to automate community disease cluster evaluations. The program creates frequency tables for number at risk and number of disease outcomes for the community, balance of parent county, and balance of state. SMRFIT then constructs standardized mortality ratios, with the community compared with balance of county and balance of state referents. Poisson regression is offered as an option for the modeling of community disease rates.

Adult↗
PubMed1991

Applicability of an image analysis system in alveolar bone loss measurement.

Clinical and epidemiological studies in the field of periodontics and endodontics often utilize radiographs to monitor or measure the changes in bone structure and density. Periodontal bone loss or gain can be quantified on a radiograph by measurement of the distance between the bottom of the bony pocket and the apical contour of the involved tooth. The objective of this investigation was to study the accuracy of an image analysis system (IAS) to measure changes in height of the interproximal crest on radiographs. Artificial bone lesions were introduced in a dissectioned part of a human mandible. The distances between crest and apices were measured with a micrometer (MM). Radiographs were produced with horizontal and vertical deviations of 10 degrees. The radiographs were digitized and processed by computer. The landmarks in the digital image were enhanced mathematically and by histogram-based thresholding. The depth of the introduced defect was increased 6 times, followed by the measurement procedure. The IAS produced measurements of crown-apex distances with an accuracy of 0.066 to 0.358 mm. Repeated crest height measurements were recorded with an accuracy of 0.112 to 0.184 mm. Both the histogram-based binarization and the ellipse-fitting type of contour detection could be applied precisely. Misangulation errors during radiographic exposure of 10 horizontal or vertical did not statistically significant influence the IAS-measurements. The IAS can be applied in clinical trials and follow-up studies.

Alveolar Bone Loss↗
PubMed2005

A neural systems analysis of the potentiation of feeding by conditioned stimuli.

Associative learning processes play many important roles in the control of food consumption. Although these processes can complement regulatory mechanisms in the control of eating by providing opportunities for the anticipation of upcoming needs, they may also contribute to inappropriate or pathological consumption patterns by overriding internal regulatory signals. In this article, we first review some of the ways in which associative learning can contribute to the control of feeding, and then describe a neural systems analysis of a simple animal model of the control of feeding by Pavlovian-conditioned stimuli (CSs). Food-sated rats increase their food consumption after presentation of CSs that were previously paired with food while the rats were food-deprived. This cue-potentiated feeding is independent of conditioned approach responses, and is at least somewhat specific to the foods associated with those CSs. A series of studies that used neuroanatomical tract tracing, immediate early gene expression, and neurotoxic disconnection lesion techniques implicated circuitry that includes the basolateral complex of the amygdala, the lateral hypothalamus, and the medial prefrontal cortex, but not the amygdala central nucleus, nucleus accumbens, or lateral orbitofrontal cortex, in cue-potentiated feeding. These studies also showed dissociations between cue-potentiated feeding and other learned motivational phenomena that are known to depend on function of amygdala systems. The data suggest that cue-potentiated feeding is uniquely mediated by cortical and amygdalar neurons that directly target the lateral hypothalamus, and thus gain access to hypothalamic neuropeptide and other systems involved in the promotion and suppression of eating.

Animals↗
PubMed2005

A digital image analysis system for identifying filter vent blocking on ultralight cigarettes.

Filter ventilation is the dominant design feature on modern cigarettes, diluting the mainstream smoke with air and reducing tar and nicotine yields in the standard assay. Smokers are generally unaware of vent holes and often cover them with lips or fingers while smoking, reducing or eliminating the air dilution effect and increasing intake of tar and nicotine particularly on ultra-low tar brands. A digital imaging and analysis system for the detection of vent blocking was developed. Two studies were designed to evaluate the effectiveness of three color measures (hue, saturation, and value) at discriminating whether at least 50% blocking had occurred. In study 1, saturation showed perfect discrimination between unblocked Carlton butts and butts with at least 50% of the vents blocked during syringe smoking. In study 2, saturation showed 95% accuracy at identifying Marlboro Ultra Light butts with at least four puffs blocked by smokers' lips. The results indicate that the pattern of color saturation is related to vent blocking. Implications for tobacco control research and policy are discussed.

Filtration↗
PubMed1992

A preliminary test of the replicability of a computerized occlusal analysis system.

A system for computerized occlusal analysis was tested in a laboratory. The investigation focused on the ability of the system to replicate results when sensors were used five times under a series of three levels of load that were applied to the occlusion. Also compared were the effects of zero mm immediate side shift and 0.2 mm immediate side shift on the research model. Results showed that there were both statistically significant differences (p less than or equal to 0.05 level) and nonsignificant differences scattered among the data derived from both articulator treatments.

Bite Force↗
PubMedDate not supplied

[The systems analysis of protective-adaptive reactions in immunopathology].

In the systems approach to the study into the closed control circuits (CCC) of the self-regulation apparatus two combinations have been established of functioning (variable) quantities. A decrease in somatotropin and hypoglycemia and correspondingly an increment in somatostatin and insulin determine the redundant measure of defence against injury, the converse values in the analyzed parameters determine autoimmune processes. Alternation of the above parameters accompanied by exacerbation-remission and remission-exacerbation is directed to securing an adaptive final effect--recovery. Apparent structural-and-functional disturbances in certain regulators of any CCC are accompanied by persisting pathological conditions listed for each heading.

Adaptation, Physiological↗
PubMed1996

An automated high capacity data capture and analysis system for the in vitro assessment of leukocyte adhesion under shear-stress conditions.

Parallel-plate flow chambers have been used to model the vascular microcirculation and study the in vitro dynamic adhesive interactions of leukocytes and human umbilical vein endothelial cells (HUVECs). We describe here a high capacity system which can simultaneously monitor the adhesive interaction of neutrophils and HUVECs in ten flow chambers. Automated data collection was achieved with an image analyzer controlling the autostage and autofocus attachments of an inverted microscope. Images from the flow chambers were captured via phase-contrast microscopy using a video camera and laser videodisk recorder. The images were downloaded off-line into an image analyzer for automated counting of rolling and adherent cells. Neutrophils were detected by their "phase bright' characteristics. An automated optimization procedure allowed the computer to choose the best setting for the selective detection of neutrophils. In addition, a method which utilized image averaging was used to distinguish between rolling and adherent cells. A comparison of the results obtained from the manual and automated counting methods revealed linear relationships for the counting of both adherent (r = 0.98) and rolling cells (r = 0.96) with counting efficiencies of 59% and 46%, respectively. The utility of the system was demonstrated by its ability to measure the adhesive interaction between neutrophils and HUVEC in response to stimulus such as interleukin-1 alpha (IL-1 alpha), histamine, or formyl-1-methionyl-1-leucyl-1-phenylalanine (fMLP). In conclusion, we have developed an automated assay which combines the capacity of ten flow chambers with a computerized data analysis system; the result is an efficient and reproducible assay which minimizes operator associated errors and biological variability.

Cell Adhesion↗
PubMed2004

Use of the roter interaction analysis system to analyze veterinarian-client-patient communication in companion animal practice.

OBJECTIVE: To identify specific components of veterinarian-client-patient communication during clinical appointments in companion animal practice. DESIGN: Cross-sectional descriptive study. SAMPLE POPULATION: A random sample of 50 companion animal practitioners in southern Ontario and a convenience sample of 300 clients and their pets. PROCEDURE: For each practitioner, 6 clinical appointments (3 wellness appointments and 3 appointments related to a health problem) were videotaped, and the Roter interaction analysis system (RIAS) was used to analyze the resulting 300 videotapes. Statements made during each appointment were classified by means of a communication framework reflecting the 4 essential tasks of the appointment (ie, data gathering, education and counseling, relationship building, and activation and partnership). RESULTS: 57% of the veterinarians contacted (50/87) and 99% of the clients contacted agreed to participate in the study. Mean duration of the appointments was 13 minutes. Typically, veterinarians contributed 62% of the total conversation and clients contributed 38%. Fifty-four percent of the veterinarian interaction was with the client, and 8% was with the pet. Data gathering constituted 9% of the veterinarian-to-client communication and was primarily accomplished through closed-ended questioning; 48% of veterinarian-to-client communication involved client education and counseling, 30% involved relationship building, and 7% involved activation and partnership (the remaining 6% constituted orientation). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that the RIAS was a reliable method of assessing the structure, process, and content of veterinarian-client-patient communication and that some veterinarians do not use all the tools needed for effective communication.

Adolescent↗
PubMed1990

Speech analysis systems: a survey.

Recently developed, relatively inexpensive systems make digital speech analysis available to many teachers, clinicians, and researchers who have not had access to previous systems. Addressing these prospective users, we survey five microcomputer programs and two dedicated devices for recording, editing, and analyzing speech. We review the capabilities, requirements, and user interface of each system. We recommend considerations for prospective users and for developers of the next generation of such programs and devices. Finally, we briefly survey seven additional systems.

Computers↗
PubMed2003

Continuation treatment of chronic depression: a comparison of nefazodone, cognitive behavioral analysis system of psychotherapy, and their combination.

Little is known about the relative benefits of psychotherapy, medication, and combined treatment as continuation therapies for chronic forms of major depressive disorder (MDD) after a positive response to acute treatment. We hypothesize that combined treatment would demonstrate superior continuation phase outcomes compared to either monotherapy, as evidenced by lower relapse rates and greater rates of improvement from partial to full remission. We report 16-week continuation phase outcomes for 324 patients who had participated in either the acute phase of a randomized multicenter trial of nefazodone, Cognitive Behavioral Analysis System of Psychotherapy (CBASP), or combination therapy (COMB) for chronic forms of MDD. Patients entering the continuation phase had either fully or partially remitted after 12 weeks of acute phase treatment. The primary efficacy measure was the 24-item Hamilton Rating Scale for Depression. For patients in remission at acute phase exit, 73.3% (107/146) maintained their remitted status at endpoint of the continuation phase. Of those having a partial remission at acute phase exit, 52.9% (92/174) achieved full remission by end of continuation. A greater proportion of patients maintained a partial or full remission status on COMB (90%) compared to nefazodone (80%, p=0.011) or to CBASP (82%, p=0.042). These differences reflected greater symptom re-emergence in the partial remission groups on CBASP and nefazodone monotherapy compared to COMB. Continuation treatment assignment was not randomized or blinded. There was no placebo group. Most patients with chronic forms of MDD sustained their acute phase response and more than 50% of partial remitters achieved full remission while continuing treatment with nefazodone, CBASP, or COMB. COMB was associated with less symptom re-emergence during the continuation phase than either monotherapy, particularly for partial remitters.

Adolescent↗
PubMed2005

Defining standard of care in the developing world: the intersection of international research ethics and health systems analysis.

In recent years there has been intense debate regarding the level of medical care provided to 'standard care' control groups in clinical trials in developing countries, particularly when the research sponsors come from wealthier countries. The debate revolves around the issue of how to define a standard of medical care in a country in which many people are not receiving the best methods of medical care available in other settings. In this paper, we argue that additional dimensions of the standard of care have been hitherto neglected, namely, the structure and efficiency of the national health system. The health system affects locally available medical care in two important ways: first, the system may be structured to provide different levels of care at different sites with referral mechanisms to direct patients to the appropriate level of care. Second, inefficiencies in this system may influence what care is available in a particular locale. As a result of these two factors locally available care cannot be equated with a national 'standard'. A reasonable approach is to define the national standard of care as the level of care that ought to be delivered under conditions of appropriate and efficient referral in a national system. This standard is the minimum level of care that ought to be provided to a control group. There may be additional moral arguments for higher levels of care in some circumstances. This health system analysis may be helpful to researchers and ethics committees in designing and reviewing research involving standard care control groups in developing country research.

Control Groups↗
PubMed2002

[Detailed evaluation of the agarose diffusion test in biocompatibility study with a microscopic image analysis system. Effect of plasma sterilization on biocompatible of an improved photoset polymer].

In addition to sterilizability, biocompatibility is a further necessary property of biomaterials. The agarose diffusion test is an established standard in vitro procedure for investigating this property. The usual method of evaluating the agarose diffusion test, based on macroscopic determination of the size of the zone of decoloration, and microscopic assessment of cell lysis, limits the power of the test. To obtain more information on the impact of plasma sterilization on the biocompatibility of a new polymer, a high-resolution computer-aided morphometric image analysis system for the quantification of the agarose diffusion test at the cellular level has been developed. This was able to detect statistically significant differences in the cell lysis rate of plasma sterilized polymer specimens before and after 4 weeks of incubation in a physiological solution. The new method provides highly detailed information on the interaction of soluble material elements and cells. In addition to cell damage by potentially toxic elements, the sensitivity of the L929 fibroblasts used in the agarose diffusion test to mechanical stress also needs to be considered and verified by further investigations.

Animals↗