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Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

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At least 307 records · Page 17Linked to original sources
PubMed1996

An ultrasonic-operated kinematic measurement system for assessment of stance balance in the clinic.

This study describes the application of a kinematic measurement system based on ultrasonic technology to enable the assessment of stance balance in the clinic. The system is composed of 1-8 ultrasonic transducer markers which transmit ultrasonic waves, and three ultrasonic receivers. The spatial position of each marker is monitored by calculation of the time interval between transmission and reception of the wave. Sway data from the waist of 44 healthy subjects and 15 hemiparetic patients were collected during quiet stance. The results distinguished between data collected with and without vision, between patients and controls, and between the two sides of the body. The findings were found to be valid and reliable in repeated measurements. RELEVANCE:--Assessment of stance balance in the clinic is a requisite for quantifying disability and measuring improvement in patients with postural control deficits. Due to high costs and complexity of operation, the use of prevailing equipment for these purposes is mainly confined to research facilities. This paper describes a unique kinematic measurement system whose low price and ease of operation make it feasible for clinical use.

Journal Article↗
PubMed1993

Neurobehavioral methods used in neurotoxicological research.

Exposure to chemicals in the environment and workplace can have adverse effects on the nervous system. Behavioral endpoints are being used with greater frequency in the hazard identification phase of neurotoxicology risk assessment. One reason behavioral procedures are used in animal neurotoxicology studies is that they evaluate neurobiological functions known to be affected in humans exposed to neurotoxic agents, including alterations in sensory, motor, autonomic, and cognitive function. In hazard identification, behavioral tests are used in a tiered-testing context. Tests in the first tier are designed to determine the presence of neurotoxicity. Examples of first-tier behavioral tests include functional observational batteries and motor activity. Second-tier tests are used to characterize neurotoxicant-induced effects on sensory, motor, and cognitive function. Second-tier tests are usually more complex and costly to perform. Reliance on behavioral endpoints in neurotoxicology risk assessment will likely increase in the future.

Animals↗
PubMed1990

Laser-based detectors in chromatographic analysis.

Advances in detection technology have been a vital part of the development of microscale chromatographic techniques. Separation techniques such as microbore liquid chromatography impose severe constraints on the permissible volume of detector cells. The use of lasers to construct a new generation of chromatographic detectors has satisfied the need for low volume detection and high sensitivity. The unique properties of laser radiation have been used to advantage in designing new approaches to the detection of optical absorbance through fluorescence emission and thermal effects. New approaches to monitoring refractive index changes and optical rotation have also been developed. Together, the combination of microscale-separation techniques and highly sensitive detection provide a powerful tool for analysing small quantities of samples. Yet, there are practical limitations arising from the cost and complexity of much of the instrumentation reported to date, as well as the difficulties of preparing small samples for analysis which have limited the wide-scale application of these methods to solve practical problems. Recent advances in laser technology such as the advent of diode lasers may be useful in overcoming some of these limitations.

Chromatography↗
PubMed1989

Research collaboration.

The complexity and cost of cardiovascular medical care dictate research to deliver high quality and cost-conscious cardiovascular care. This goal is aided by modeling medical decision making. To be useful, the modeling must be based on real data so that the results can serve as a guide to actual practice. It is suggested that a registry of randomized clinical trials and larger data bases in cardiovascular disease and health care delivery be established. The registry would be a resource for those desiring to model decision making. The registry would contain key words allowing retrieval by modelers accessing the registry and would contain contact information for consideration of possible collaborative work. The initiation of such a registry should contain plans for its evaluation to determine whether the registry itself is a cost-effective tool to encourage the needed research.

Clinical Trials as Topic↗
PubMed2006

Identification of coding single nucleotide polymorphisms and mutations by combination of genome tiling arrays and enrichment/depletion of mismatch cDNAs.

Genome tiling array technology combined with a method for both enrichment and depletion of mismatch-containing cDNA fragments offers a useful approach for detecting coding single nucleotide polymorphisms (cSNPs) and mutations in pooled cDNA samples. Enriched mismatch and perfect match cDNA samples from human primary melanoma cells and normal melanocytes were obtained by selection using mismatch repair thymine DNA glycosylase-bound beads. These cDNA samples were then labeled and hybridized to Encyclopedia of DNA Elements genome tiling arrays. The results revealed that the hybridization intensity values of potential cDNA variation regions of the enriched mismatch samples increased, whereas the hybridization intensity values of corresponding regions of the enriched perfect match samples decreased. Six potential mutations were confirmed by polymerase chain reaction product sequencing, including two novel heterozygous mutations in melanoma cells. We suggest that this strategy should increase the efficiency of both cSNP and mutation detection throughout the entire human genome and decrease the cost and complexity of genomewide analysis of cDNA variations.

Base Pair Mismatch↗
PubMed2004

Robotics in thoracic surgery.

Surgical use of robotics, or computer-assisted surgical systems (CAS), has evolved over the last 10 years; for the treatment of chest diseases, however, the development has really occurred in the last 3 to 4 years. This brief history means that there have been few publications in the medical literature, and those that exist are mostly case reports. Moreover, because of this modest experience, robotic thoracic procedures currently take more time than nonrobotic cases and, thus, are more expensive. The surgical learning curve appears to be steep, especially for the more complex procedures. As surgeons gain greater experience and the complexity and cost of the equipment are reduced, we should expect to see greater utility of CAS in thoracic surgery.

Esophagus↗
PubMed2004

Development of a thermal neutron sensor for Humanitarian Demining.

A thermal neutron sensor prototype for Humanitarian Demining has been developed, trying to minimize cost and complexity of the system as required in such application. A (252)Cf source or a sealed-tube neutron generator is employed to produce primary fast neutrons that are thermalized in a moderator designed to optimize the neutron capture reaction yield in buried samples. A description of the sensor, including the performances of the acquisition system based on a Flash ADC card and final tests with explosive simulants are reported. A comparison of the sensor performance when using a radioactive source to that when employing a sealed-tube neutron generator is presented. Limitations and possible applications of this technique are discussed.

Blast Injuries↗
PubMed2004

Assaying particle-bound polycyclic aromatic hydrocarbons from archived PM2.5 filters.

Airborne particulate matter contains numerous organic species, including several polycyclic aromatic hydrocarbons (PAHs) that are known or suspected carcinogens. Existing methods for measuring airborne PAHs are complex and costly, primarily because they are designed to collect both gas-phase and particle-phase PAH constituents. Here, we report an assay for measuring particle-bound PAHs in archived filters from the network of U.S. monitoring stations for particles less than 2.5 microm in diameter (PM2.5), without the need for deploying specialized samplers. PAHs are extracted from Teflon filters with dichloromethane, concentrated, and measured at trace levels using gas chromatography-mass spectrometry. Although PAHs with 3-6 aromatic rings can be assayed, results are only unambiguously accurate for compounds with 5- or 6-rings, due to variable vaporization losses of the more volatile 3- and 4-ring compounds during sampling and/or storage. The method was evaluated for sensitivity, recovery, precision, and agreement of paired air samples, using PM2.5 samplers locally in Chapel Hill, NC. Additionally, three sets of archived samples were analyzed from a study of PM2.5 in the Czech Republic. Levels of some 4-ring and all 5- and 6-ring PAHs in both the local and Czech samples were consistent with published results from investigations employing PAH-specific air samplers. This work strongly suggests that assessment of particle-bound 5- and 6-ring PAHs from archived PM2.5 filters is quantitatively robust. The assay may also be useful for selected 4-ring compounds, notably chrysene and benzo(a)anthracene, if PM2.5 filters are stored under refrigeration.

Filtration↗
PubMed2004

Using ion chromatography to monitor haloacetic acids in drinking water: a review of current technologies.

A review of the application of ion chromatography to the determination of haloacetic acids in drinking water is given. As it requires no sample derivatisation, ion chromatography in its various modes, such as ion-exchange, ion-interaction and ion-exclusion chromatography, is increasingly being investigated as a simpler alternative to gas chromatographic methods for the determination of polar disinfection by-products (DBPs) in drinking waters. Detection limits quoted for the regulated haloacetic acids (HAA5), are commonly in the mid to low microg/L range, however, in most cases analyte preconcentration is still necessary for detection at concentrations commonly found in actual drinking water samples. The coupling of ion chromatography to electrospray mass spectrometry provides a potential future direction, with improved sensitivity and selectivity compared to conductivity based detection, however associated cost and complexity for routine analysis is currently relatively high.

Acetates↗
PubMed2004

A simple and low-cost Internet-based teleconsultation system that could effectively solve the health care access problems in underserved areas of developing countries.

In many developing countries including Turkey, telemedicine systems are not in wide use due to the high cost and complexity of the required technology. Lack of these systems however has serious implications on patients who live in rural areas. The objective of this paper is to present a simple and economically affordable alternative to the current systems that would allow experts to easily access the medical data of their remote patients over the Internet. The system is developed in client-server architecture with a user-friendly graphical interface and various services are implemented as dynamic web pages based on PHP. The other key features of the system are its powerful security features and platform independency. An academic prototype is implemented and presented to the evaluation of a group of physicians. The results reveal that the system could find acceptance from the medical community and it could be an effective means of providing quality health care in developing countries.

Computer Graphics↗
PubMed2006

Cancer gene search with data-mining and genetic algorithms.

Cancer leads to approximately 25% of all mortalities, making it the second leading cause of death in the United States. Early and accurate detection of cancer is critical to the well being of patients. Analysis of gene expression data leads to cancer identification and classification, which will facilitate proper treatment selection and drug development. Gene expression data sets for ovarian, prostate, and lung cancer were analyzed in this research. An integrated gene-search algorithm for genetic expression data analysis was proposed. This integrated algorithm involves a genetic algorithm and correlation-based heuristics for data preprocessing (on partitioned data sets) and data mining (decision tree and support vector machines algorithms) for making predictions. Knowledge derived by the proposed algorithm has high classification accuracy with the ability to identify the most significant genes. Bagging and stacking algorithms were applied to further enhance the classification accuracy. The results were compared with that reported in the literature. Mapping of genotype information to the phenotype parameters will ultimately reduce the cost and complexity of cancer detection and classification.

Algorithms↗
PubMed2003

High-field magnetic resonance techniques for brain research.

High-field magnetic resonance imaging scanners with a static magnetic field of 3 Tesla or higher are becoming ubiquitous in clinical and basic neurosciences. Given the high cost and complexity of operation, it is important to ask whether or not and how the use of high-field magnets can be beneficial for the neurosciences. What new questions can be addressed? Which new insights can we expect from these new tools? In addition, what are the limitations of these new techniques? This review discusses the three most important applications of the high-field magnetic resonance techniques for the neuroscience community: first, functional magnetic resonance imaging, second, in vivo spectroscopy, and third, in vivo fiber tracking on the basis of diffusion tensor imaging.

Animals↗
PubMed2025

Polygenic Risk Scores Predicting Estimated GFR Validated With Iohexol Clearance.

INTRODUCTION: Genome-wide association studies (GWAS) have identified hundreds of single nucleotide variants (SNVs) associated with estimated glomerular filtration rate (eGFR). eGFR has been used as a proxy phenotype because of the complexity and cost of measured GFR (mGFR) in large studies. Because eGFR is influenced by non-GFR factors, these GWAS results may be biased compared with a hypothetical study using mGFR. We aimed to investigate this by comparing aggregate measures of genetic effects on mGFR and eGFR. METHODS: We studied 1492 persons from the Renal Iohexol Clearance Survey (RENIS) cohort, a representative sample of the general population in Northern Norway without preexisting cardiovascular disease, kidney disease, or diabetes. We measured iohexol-clearance, and genotyping was performed with a microarray chip enriched for GFR-related SNVs. We compared the performance of 3 published polygenic risk scores (PGS) developed for creatinine-based eGFR (eGFRcr), narrow-sense heritability (h2) and the mean effect of SNVs on mGFR, eGFRcr, cystatin C-based eGFR (eGFRcys) and eGFRcr-cys. RESULTS: The performance of the PGS differed for mGFR and the 3 eGFRs, with best performance for prediction of eGFRcr (P < 0.05). However, when the beta coefficients of the SNVs in the 3 PGS were estimated in the RENIS-cohort, their magnitude was 11% to 46% greater for mGFR than for the 3 eGFR methods in 8 of 9 comparisons (P < 0.05). mGFR had higher h2 (0.47) than eGFRcr (0.21), eGFRcys (0.37), and eGFRcr-cys (0.42). CONCLUSIONS: SNVs with non-GFR effects on creatinine and cystatin-C influence GWAS results. The results of GWAS using eGFR should be validated using experimental and other more precise methods.

chronic kidney disease↗
PubMed2004

The DATAS rationale and design: a controlled, randomized trial to assess the clinical benefit of dual chamber (DDED) defibrillator.

Single chamber (SC) implantable cardioverter defibrillators (ICDs) have several limitations that might be relevant during follow-up, like atrial pacing requirements, inadequate therapies, sustained atrial tachyarrhythmias and difficulties to achieve an accurate diagnosis of the arrhythmia. Dual chamber (DC) ICDs offer an attractive and rational solution, although controversy remains if the costs and complexity of these devices offer a real clinical advantage. The Dual Chamber & Atrial Tachyarrhythmias Adverse Events Study (DATAS) was designed to analyze the ability of DC ICD, DDED, to reduce clinically significant adverse events compared with SC ICD in a non-selected population with conventional indications for ICD implantation. This is a prospective, multicentre, randomized, open labelled study, with three arms: two of them (simulated SC ICD and true DC ICD) cross-over, and the third (true SC ICD) parallels the other two. The composite primary end point comprises four Clinically Significant Adverse Events (CSAE): (1) all-cause mortality, (2) invasive intervention, hospitalization or prolongation of hospitalization due to cardiovascular cause, (3) inappropriate shocks, and (4) sustained symptomatic atrial tachyarrhythmias that (a) require urgent termination or (b) last more than 48h leading to therapeutic intervention. Secondary end points constitute each of the individual components of CSAE, cardiovascular status, quality of life and a detailed analysis of atrial and ventricular arrhythmias. To date (June 2003) there have been 343 patients enroled from 947 screened patients. The projected enrollment includes 360 patients and the conclusion of the study is expected at the beginning of 2005.

Arrhythmia, Sinus↗
PubMedDate not supplied

AIDES to improving medication adherence in older adults.

Medication regimens for older adults are often complex and costly. Designing, implementing, and maintaining an appropriate treatment regimen is challenging. The AIDES method is built on the principles of completing a comprehensive medication Assessment; partnering with patients to ensure Individualization of the regimen; choosing appropriate Documentation; providing accurate and ongoing Education tailored to the age group and needs of the individual; and continuing Supervision after initiation.

Aged↗
PubMed2006

Quantitative measurement of handwriting in the assessment of drug-induced parkinsonism.

Monitoring drug-induced side effects is especially important for patients who undergo treatment with antipsychotic medications, as these drugs often produce extrapyramidal side effects (EPS) resulting in movement abnormalities similar to parkinsonism. Scientists have developed several objective laboratory tests to measure and research drug-induced movement disorders, but equipment and tests are complex and costly and have not become accepted in large-scale, multi-site clinical trials. The goals of this study were to test whether a simple handwriting measure can discriminate between individuals with psychotropic-induced parkinsonism, Parkinson's disease, and healthy individuals, and to examine some of the psychometric properties of the measure. We examined pen movement kinematics during cursive writing of a standard word in 13 patients with idiopathic Parkinson's disease (PD), 10 schizophrenia patients with drug-induced parkinsonism (SZ), and 12 normal healthy control participants (NC). Participants were instructed to write the word "hello" in cursive twice, at three vertical height scales. Software was used for data acquisition and analysis of vertical stroke velocities, velocity scaling, and smoothness. There were four important results from this study: (1) both SZ patients with drug-induced EPS and PD participants exhibited impaired movement velocities and velocity scaling; (2) performance on the velocity scaling measure distinguished drug-induced EPS from normal with 90% accuracy; (3) SZ, but not PD participants displayed abnormalities in movement smoothness; and (4) there was a positive correlation between age and magnitude of the velocity scaling deficit in PD participants. This study demonstrates that kinematic analyses of pen movements during handwriting may be useful in detecting and monitoring subtle changes in motor control related to the adverse effects of psychotropic medications.

Adult↗
PubMed2005

Identification of Bacillus spp., Escherichia coli, Salmonella spp., Staphylococcus spp. and Vibrio spp. with 16S ribosomal DNA-based oligonucleotide array hybridization.

Rapid identification of the genus and species of bacteria in foods and clinical specimens is important. In this report, DNA sequences of bacterial 16S rDNA were used to develop the oligonucleotide array for the identification of bacterial strains of Bacillus spp., Escherichia coli, Salmonella spp., Staphylococcus spp. and Vibrio spp. Most of these bacterial strains may cause food-borne outbreaks or sporadic cases. A rapid (<4 h) detection method that used universal PCR primers to amplify the variable regions of bacterial 16S rDNA, followed by reverse hybridization of the PCR products, which were biotin labeled, to the oligonucleotides arrayed on the chip was developed. Fifteen oligonucleotide probes were selected and spotted on the nylon strip to determine the array hybridization patterns. It was successful in discriminating Bacillus spp., E. coli, Salmonella spp., Staphylococcus spp. and Vibrio spp. with identification, in general, to the genus level, not species level. As 182 randomly selected strains were assayed, the detection rate was found higher than 98%. Except for 3 strains, the remaining 179 strains were correctly identified and no cross reactions were observed. These 179 strains generated five hybridization patterns. Adding more oligonucleotide probes to the array may allow the detection of more bacterial genera and species without significantly increasing the complexity or cost.

Bacillus↗
PubMed2006

The impact of computerised physician order entry systems on pathology services: a systematic review.

PURPOSE: Computerised physician order entry (CPOE) systems hold the promise of significant improvements to health care delivery and patient care. The implementation of such systems is costly and complex. The purpose of this paper is to review current evidence of the impact of CPOE on hospital pathology services. METHODS: This paper presents a review of the literature (1990-August 2004) about CPOE systems and identifies indicators for measuring the impact of CPOE on pathology services. RESULTS: Nineteen studies which contained some form of 'control' group, were identified. They featured a variety of designs including randomised controlled trials, quasi-experimental and before and after studies. We categorised these into three groups: studies comparing pathology CPOE systems (with no decision support) to paper systems; pathology CPOE systems (with decision support) to paper systems; and pathology CPOE systems with specific pathology features compared to systems without those features. We identified 10 areas of impact assessment and 39 indicators used to measure the impact of CPOE on different stages of the pathology test ordering and reporting process. CONCLUSION: We conclude that while some data suggest that CPOE systems are beneficial for clinical and laboratory work processes, these data are limited, and further research is needed. Few data are available regarding the impact of CPOE on patient outcomes.

Diffusion of Innovation↗