SEARCH · PubMed Health

Results for “IDENTIFICATION”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,207 records · Page 67Linked to original sources

PubMed2003

Online hydrogen-deuterium exchange and a tandem-quadrupole time-of-flight mass spectrometer coupled with liquid chromatography for metabolite identification in drug metabolism.

A method for metabolite identification in drug discovery and development utilizing online hydrogen-deuterium (H-D) exchange and a tandem-quadrupole time-of-flight mass spectrometer coupled with liquid chromatography has been developed for the first time. For purposes of evaluating this method, nimodipine is incubated with rat, dog, monkey, and human hepatic microsomes over a 60-min period. This procedure involves the replacement of H(2)O with D(2)O in the mobile phase. The equilibration time required to change (switch) from H(2)O in the mobile phase into D(2)O is approximately 10 min. There is no significant difference between the retention times in H(2)O or D(2)O mobile phase. The results show that the separations of nimodipine and its metabolites and the subsequent H-D exchanges were achieved online. This leads to the identification of nimodipine metabolites formed in vitro. Five metabolites of nimodipine are identified and characterized. These metabolites are formed by dehydrogenation, demethylation of methoxy group, cleavage of the ester groups by hydrolysis or oxidation, and hydroxylation of methyl groups. The combination of the H-D exchange process and the assay system is found to be a powerful tool for the study of metabolite identification. The method appears to be highly desirable for identification of metabolites produced by dehydrogenation, oxidation, and dealkylation, which are discussed herein. This method also greatly enhances throughput, which in turn facilitates the ability to rapidly provide metabolite elucidation.

Animals↗

PubMed1994

Haemophilus parainfluenzae endocarditis: application of a molecular approach for identification of pathogenic bacterial species.

Haemophilus parainfluenzae is both a human oropharyngeal commensal bacterium and a cause of serious invasive disease. The fastidious growth characteristics of this organism and the poor specificity of traditional methods for species identification are likely to have led to inaccuracies in the diagnosis of infections caused by H. parainfluenzae and related organisms. We report a case of H. parainfluenzae endocarditis in which confusion related to microbial identification was resolved by the analysis of 16S ribosomal RNA sequences. Rapid identification was facilitated by amplification of 16S ribosomal DNA directly from cultured cells with use of the polymerase chain reaction and by direct DNA sequence determination of the amplified product. This procedure is potentially useful for the identification of fastidious bacterial pathogens by reference laboratories.

Adult↗

PubMedDate not supplied

Some considerations regarding the classification and identification of mycobacteria.

The principles of classification and identification of microorganisms are stated briefly. Reliable classification and identification are achieved by numerical methods. A simple method of testing the distinctness of taxa (clusters or species) involves three steps: determination of the hypothetical median or mean organism (HMO) for each taxon, estimation of matching coefficients (M values) for individual strains of each taxon to the HMO of the same taxon and to HMOS of other taxa, and definition of the range of a taxon as M +/- 2SD, where M is the mean M value to the HMO. The minimal number of characteristics needed for reliable classification is greater than 40, and none of the characteristics should be related or biased. A species should be defined by more than four strains. After distinct taxa are defined and named as species, new isolates are tested to determine which taxon they belong to. This test is done by a numerical method: comparison of a new isolate with the HMO of various species and testing whether the resulting M values fall within the ranges of any of these species. If an M value of a new isolate falls within the range of taxon X and M values to the HMOS of other species are outside the limits of those species, the isolate is identified as belonging to taxon X. A simple, conventional (nonnumerical) identification system consisting of a small number of tests may be used in clinical laboratories, but one should always keep in mind that identification by such a system often leads to misidentification. Causes of misidentification are false reactions (misjudgment of results), inadequate choice of test characteristics, and use of too small a number of tests.

Diagnostic Errors↗

PubMedDate not supplied

Application of pyrolysis mass spectrometry to the classification and identification of mycobacteria.

Application of modern pyrolysis techniques offers the possibility for mass spectrometric analysis of complete bacterial cells. It was shown that pyrolysis mass spectra provide fingerprints of mycobacterial cells that are characteristic on the (sub)species level. Computer-aided comparisons of the spectra for mycobacteria were used for identification of unknown strains as members of either the "tuberculosis complex" (Mycobacterium tuberculosis, Mycobacterium bovis-BCG, M. bovis) or of the group referred to as "atypical mycobacteria." Pyrolysis mass spectrometry was performed with a completely automated instrument, and spectra were evaluated by two computerized numerical methods. The first method has general applicability to mass spectrometry data, while the second was devised for the routine identification of the "tuberculosis complex." With use of the latter method, 125 strains were identified. A positive correlation of 94.4% was found between the results of this method and the results of the usual bacteriologic procedures; 1.6% of all strains were given a falsely negative identification, and 4.0% were given a falsely positive identification.

Analysis of Variance↗

PubMed2004

Use of information about maternal distress and negative life events to facilitate identification of psychosocial problems in children.

BACKGROUND: Despite the availability of effective screening measures, primary care physicians fail to identify and manage many children with psychosocial problems. Physicians often have information about significant negative events in a child's life. The present study evaluated the potential utility of using information about negative life events to facilitate physician identification of children with psychosocial problems. METHODS: Negative life events, maternal distress and child psychosocial functioning measures were completed by 185 mothers of children, aged 4-12 years. Family physicians provided data about the children's psychosocial functioning. RESULTS: Mothers identified 15.1% (n = 28) of the children as having psychosocial problems. Physicians correctly identified 21% (n = 6) of these at-risk children. Physician use of negative life events would have led to the identification of 39.2% (n = 11) at-risk children. Information about maternal distress and negative life events would have resulted in an additional 18% (n = 5) of children identified by the physicians. Information about maternal distress alone would have resulted in an identification rate of 53.5% (n = 15). CONCLUSIONS: Using information about negative events in a child's life, physicians could improve their rate of identification of children with psychosocial problems. Children who have had more than two negative events in their lives are at increased risk for psychosocial problems.

Adult↗

PubMed1996

Longitudinal changes in smell identification.

BACKGROUND: Cross-sectional studies have demonstrated that olfactory function diminishes with increasing age, which may impact on the safety and quality of life of older persons. To date, however, there have been no published longitudinal studies on olfaction. The purpose of this study was to examine the influence of age and gender on smell identification over a 3-year period in a group of generally healthy men and women. METHODS: Males (n = 85) and females (n = 76) between the ages of 19 and 95 years were administered the University of Pennsylvania Smell Identification Test (SIT) over a 3-year span as part of the oral physiology component of the Baltimore Longitudinal Study of Aging. A linear mixed-effects regression model was used to determine how longitudinal changes in SIT scores differ with respect to gender, history of medical problems, and use of prescription medications. RESULTS: Over the 3-year period, SIT scores diminished progressively with increased age. Women and men in the eighth decade of life experienced a decline of greater than one SIT point per year. Females consistently performed better than males in smell identification. Similar results were obtained regardless of medical problems or medication usage. CONCLUSIONS: These results extend the conclusions of previous cross-sectional olfactory studies and indicate that smell identification deteriorates progressively with greater age. Furthermore, age-related declines in olfaction occur even in the absence of overt medical problems.

Adult↗

PubMed2000

Odor identification: influences of age, gender, cognition, and personality.

The aim of this study was to examine the influences of age, gender, cognitive abilities, and personality styles on odor identification. Participants (N = 532) aged 45-87 years from the Swedish Adoption/Twin Study of Aging were assessed with a Swedish version of the National Geographic Smell Survey. Both detection and identification of olfactory information were impaired with age. Gender had no effect on detection or identification. Hierarchical regressions revealed that proficiency in semantic memory, intensity perception, and personality style (i.e., neuroticism, impulsivity, and lack of assertiveness) were potent predictors for successful odor identification, even when individual variations in chronological age, sex, education, and global cognitive functioning were taken into account.

Age Factors↗

PubMed1987

Effects of age, stimulus selection, and retrieval environment on odor identification.

Age differences in odor identification were investigated by using relatively familiar and unfamiliar chemical stimuli and enhancing the retrieval environment by restrictive reminding of memories evoked by stimulus during initial presentation. Age differences were seen in initial identification, in learning the labels of items in the stimulus set, in presentation. Age differences were seen in initial identification, in learning the labels of items in the stimulus set, in forgetting over a 24-hr period, but not in forgetting over a 7-day period. Old (n = 20) and young (n = 20) study participants benefitted equally from enrichment of retrieval environment with restrictive reminding of memories evoked at initial presentation. Item analysis indicated that selection of stimuli had a significant effect on age differences in odor identification.

Adolescent↗

PubMedDate not supplied

A simple automated procedure for the detection and identification of peaks in gas chromatography--continuous scan mass spectrometry. Application to systematic toxicological analysis of drugs in whole human blood.

Gas chromatography-mass spectrometry (GC-MS), which combines the separation power of GC with the power of MS for the identification of unknown compounds, possesses high potential in systematic toxicological analysis (STA). Different factors, however, do not allow this potential to be fully exploited. Between them, the low selectivity of the mass spectrometer operating in continuous scan plays a critical role, in many cases precluding the possibility of selecting mass spectra in the total ion chromatogram (TIC) sufficiently clean for a positive identification by library search, even when using reverse search algorithms. Moreover, the large amount of information contained in GC-MS data file that results from the analysis of a biological extract makes the efforts of manual search almost useless and requires the availability of reliable methods for the automated detection and identification of peaks in a TIC. In this paper, a simple procedure that improves the performance of a bench-top GC-MS system in the purification of mass spectra of coeluting compounds and that can be easily combined with the automated processing of a GC-MS data file is described. It is based on the subtraction of the intensities of successive pairs of scans in the TIC, on the detection of positive and negative peaks in the transformed chromatograms, and on the search of the corresponding background-subtracted electron ionization mass spectra against reference libraries. In order to evaluate the proposed procedure, GC-MS data files obtained for the analysis of extracts of blank whole blood spiked with more than 100 drugs, poisons, and their metabolites at a concentration of 0.5 mg/L were used. Compared with the search of the raw TICs, the proposed procedure increased the number of identified substances and, in many cases, obtained higher match quality values for identification.

Amitriptyline↗

PubMedDate not supplied

System evaluation and substance identification in systematic toxicological analysis by the mean list length approach.

In systematic toxicological analyses (STA), analytical methods are needed with a high Identification Power. The mean list length (MLL) approach, which is an improved and extended version of the Identification Power concept, provides an objective tool for the evaluation and optimum choice of analytical methods for STA. The MLL approach is elucidated and applied to the screening for basic drugs by thin layer chromatography (TLC) and gas-liquid chromatography (GLC). Its usefulness for TLC and GLC systems for the identification of these basic drugs has been evaluated for both single systems and combinations of systems. The MLL approach is also substance directed and can be applied to computerized data searches and substance identification. The method is applicable for single analytical systems and combinations of systems. Mixtures of substances can also be handled.

Chromatography, Gas↗

PubMed2005

Brief report: the relationship between chronic illness and identification and management of psychosocial problems in pediatric primary care.

OBJECTIVE: To compare identification, management, and barriers to treatment for psychosocial concerns in children with and without a chronic illness. METHODS: Using data from the Child Behavior Study (CBS), provider rates of identification, treatment, and reports of barriers to treatment were compared in children with and without a chronic illness. Of the 21,065 children ranging in age from 4 to 15 years, 808 children were identified with a chronic illness and were matched on eight demographic variables with 763 healthy children. RESULTS: Providers identified psychosocial concerns in significantly more children with a chronic illness (36.8%) than healthy children (20.2%). Among children with psychosocial concerns, rates of identification, treatment, and barriers to treatment did not differ across the two groups. CONCLUSIONS: Chronic illness did not present more barriers to the management of psychosocial concerns. Increased rates of identification and treatment of psychosocial concerns require attention to general barriers to treatment and screening.

Adolescent↗

PubMed2005

oPOSSUM: identification of over-represented transcription factor binding sites in co-expressed genes.

Targeted transcript profiling studies can identify sets of co-expressed genes; however, identification of the underlying functional mechanism(s) is a significant challenge. Established methods for the analysis of gene annotations, particularly those based on the Gene Ontology, can identify functional linkages between genes. Similar methods for the identification of over-represented transcription factor binding sites (TFBSs) have been successful in yeast, but extension to human genomics has largely proved ineffective. Creation of a system for the efficient identification of common regulatory mechanisms in a subset of co-expressed human genes promises to break a roadblock in functional genomics research. We have developed an integrated system that searches for evidence of co-regulation by one or more transcription factors (TFs). oPOSSUM combines a pre-computed database of conserved TFBSs in human and mouse promoters with statistical methods for identification of sites over-represented in a set of co-expressed genes. The algorithm successfully identified mediating TFs in control sets of tissue-specific genes and in sets of co-expressed genes from three transcript profiling studies. Simulation studies indicate that oPOSSUM produces few false positives using empirically defined thresholds and can tolerate up to 50% noise in a set of co-expressed genes.

Algorithms↗

PubMed2006

Computational identification of transcriptional regulatory elements in DNA sequence.

Identification and annotation of all the functional elements in the genome, including genes and the regulatory sequences, is a fundamental challenge in genomics and computational biology. Since regulatory elements are frequently short and variable, their identification and discovery using computational algorithms is difficult. However, significant advances have been made in the computational methods for modeling and detection of DNA regulatory elements. The availability of complete genome sequence from multiple organisms, as well as mRNA profiling and high-throughput experimental methods for mapping protein-binding sites in DNA, have contributed to the development of methods that utilize these auxiliary data to inform the detection of transcriptional regulatory elements. Progress is also being made in the identification of cis-regulatory modules and higher order structures of the regulatory sequences, which is essential to the understanding of transcription regulation in the metazoan genomes. This article reviews the computational approaches for modeling and identification of genomic regulatory elements, with an emphasis on the recent developments, and current challenges.

Animals↗

PubMed2000

Genome profiling: a realistic solution for genotype-based identification of species.

Species identification is the basis of Biology and has been carried out based on phenotype. Although some genes, such as that for 16S rRNA, have been used for species confirmation, identification of species based only on genotype has never been done before, although recent whole genome sequencing studies have demonstrated it to be possible in principle. However, it is evidently unrealistic for routine experiments of species identification. This paper clarifies that a very limited amount of information derived from a genome sequence is sufficient for identifying the species. It also proves that Genome Profiling [Nishigaki, K., Amano, N., and Takasawa, T. (1991) Chem. Lett. 1097-1100], TGGE analysis of random PCR products, can not only fulfill such requirements, but also serve as a universal method to analyze species. Thus, this compact technology can be used in many fields of biology, especially in microbe-related disciplines such as microbial ecology and epidemiology where exact knowledge about all members of a population is essential but previously difficult to obtain. This is the first demonstration that genotype-based identification of species is possible using a simple and uniform protocol for all organisms.

Animals↗

PubMed1980

Mass identification: a multidisciplinary operation. The Dutch experience.

The organization of the Disaster Unit of the National Police Force of the Netherlands is described. Several aspects of its operation are discussed, including the recovery operation, technical identification, tactical identification, and finally the details of the Dutch operation in the disaster at Tenerife. The Tenerife disaster operation included the work at the crash site and temporary morgue setup, the method of technical identification, and the supplementary investigations upon return to the Netherlands. The success of this difficult task, shown by positive identification of 82% of the bodies of the victims, is truly remarkable.

Accidents, Aviation↗

PubMed1991

Use of orthopantomographs in forensic identification.

Radiographs of the head region were used for identification of 17 victims during an 11-year period in the Department of Forensic Medicine, University of Turku, Finland. Examinations resulted in positive identification of 10 victims. Proof of identity of four people was based on exclusion identifications. In one case, comparable information supporting the identity was achieved. Due to insufficient ante- and postmortem material, two individuals remained unidentified by radiological methods. The use of orthopantomography in identification is recommended because it enables visualization of the structures of the jaws and related areas on a single radiograph.

Accidents↗

PubMed1997

Radiographic identification of fragmentary human remains from a mass disaster.

Positive identification of human remains is one of the most important tasks in mass disaster management. Here we report on the use of radiography for positive identification of fragmentary human remains recovered from the scene of a terrorist bombing in the Jewish-Argentine Mutual Association Center in Buenos Aires, Argentina, in July 1994. Radiographic examination of all human remains from mass disaster scenes is recommended for identification purposes. Establishing a computerized data bank of antemortem information on missing persons and postmortem findings in disaster victims greatly facilitates and expedites the identification process.

Aged↗

PubMed2002

Personal identification based on radiographic vertebral features.

Personal identification of human remains constitutes about 10% of the normal caseload of any forensic medicine practice. Identification can be achieved by a variety of methods, one of which is the comparison of antemortem and postmortem radiographs. There are numerous accounts of cranial and dental radiographic features useful for identification, whereas the availability of postcranial radiographs and especially plates that depict the vertebral column is less widespread among the forensic community. The authors here review the various vertebral features instrumental in positive identification that can be identified on radiographs of the spine.

Adult↗