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Estimation of cardiac function by means of radiocardiographic function analysis.

The radiocardiographic function analysis represents a relatively simple procedure for the clinician to collect information concerning the changes of cardiac dynamics. The advantage of this method is to register non-invasively changes in cardiac dynamics at rest and during exercise such as those of enddiastolic volume, stroke volume, endsystolic volume, ejection time and filling time, and to permit the calculation of mean ejection velocity, etc. After insertion of a cardiac catheter, it is possible to record the corresponding pressure pulse in the right ventricle or in the pulmonary vessels simultaneously.

Cardiac Catheterization

Prediction of severe coronary artery disease using computerized ECG measurements and discriminant function analysis.

This study tested the hypothesis that discriminant function analysis of clinical and exercise-test variables including computerized ST measurements could improve the prediction of severe coronary artery disease. Secondary objectives were to demonstrate the effect of digoxin and/or resting electrocardiographic (ECG) abnormalities, and to evaluate the relative importance of ST measurements made during the recovery phase and in the three lead group areas. The design was a retrospective analysis of data collected during exercise testing and coronary angiography. The ECG data were gathered and stored in digital format on optical discs and all ST measurements were made off-line using the authors' own software. Univariate and multivariate analytic methods were used to analyze all pretest characteristics as well as hemodynamic and computerized ECG responses to exercise. A 1,000-bed Veterans Affairs Medical Center served as the setting. The study included 446 male veterans who underwent a sign or symptom limited treadmill exercise test and coronary angiography. Analysis was also performed on a subset of this population formed by excluding patients receiving digoxin or with resting ECGs exhibiting left ventricular hypertrophy or ST depression (n = 328). In the total study population, the authors derived a treadmill score using discriminant function analysis. This score included: (1) the time-slope area in lead V5 during recovery; (2) delta heart rate; (3) angina pectoris during the exercise test; and (4) presence of diagnostic Q waves on the resting ECG. This score was effective in predicting triple vessel/left main disease and outperformed exercise-induced ST depression for predicting severe coronary artery disease. After exclusion of patients with ECGs exhibiting left ventricular hypertrophy or resting ST depression and patients receiving digoxin, discriminant function analysis chose: (1) the time-slope area in lead V5 during recovery and (2) delta heart rate. Exclusion of these patients resulted in a nonsignificant decrease in specificity of all ST criteria. ST-segment amplitude or slope in lead V5 at 3.5 minutes in recovery clearly outperformed the maximal exercise measurements in both groups. Summing the depressions or selecting the most depression in the three areas (ie, lateral-V5, inferior-II, anterior-V2) did not improve test performance. Leads other than V5 did not contain significant diagnostic information. A quantitative approach to exercise testing using discriminant function analysis enhanced the tests' performance for predicting severe coronary disease. The inclusion of patients taking digoxin or with resting ECG abnormalities nonsignificantly decreases the specificity of all ST criteria.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult

[Functional analysis in orthodontics].

After completed orthodontic treatment, clinical functional analysis and instrumental occlusal analysis were carried out in 60 patients, with the Stuart pantograph and the Stuart articulator. The results of the functional analysis were put into relation with orthodontic qualification and the technique used.

Adolescent

Structural and functional analysis of the amdR regulatory gene of Aspergillus oryzae.

We have isolated the Aspergillus oryzae homologue of the amdR regulatory gene of Aspergillus nidulans by cross hybridization. Sequence analysis and functional studies have shown that the amdR genes are highly conserved and functionally interchangeable between the two species. The homology between the two genes extends throughout most of the coding sequences, including sequences encoding the DNA-binding domain and putative activation domains. Two regions of nonconserved sequence were also identified. Studies using various amdS::lacZ fusion constructs indicate that the A. oryzae gene product binds similar sequences and responds to inducer in a similar manner to the A. nidulans protein. Inactivation of the A. oryzae gene results in the inability to grow on gamma-amino-butyric acid (GABA) as a carbon and/or nitrogen source indicating that GABA utilization is amdR-dependent in A. oryzae as it is in A. nidulans.

Amino Acid Sequence

Structural and functional analysis of a replication enhancer: separation of the enhancer activity from origin function by mutational dissection of the replication origin gamma of plasmid R6K.

The plasmid R6K possesses three distinct origins of replication: alpha, beta, and gamma. The replication origin gamma of plasmid R6K performs a dual function: (i) as an origin itself and (ii) as an enhancer element required in cis for the activation at a distance of the other two replication origins alpha and beta. We have dissected the gamma origin/enhancer by site-directed mutagenesis and have reached the following conclusions. The origin function can be specifically inactivated without impairing the enhancer function by insertion and/or deletion mutations near the opposite ends of the origin gamma sequence. One such mutation deleted sequences that included the left DnaA site I. The second mutation involved insertion of linker sequences that resulted in a spatial alteration between the right DnaA site II and the VIIth pi binding iteron (tandemly repeated binding sites). Other mutations that either partly or completely deleted the A+T-rich sequence adjacent to, but not including, the pi binding iterons also abrogated enhancer and origin function and suggested that pi binding sites were necessary but not sufficient for enhancer activity. Finally, the functional analysis of a set of mutants of the gamma origin/enhancer suggested that a continuous stretch of 300 base pairs is necessary for origin gamma function and that the sequences that included the binding sites for pi, DnaA, and integration host factor proteins are required in the correct stereochemical alignment to impart origin activity.

Bacterial Proteins

[Functional analysis in orthodontics and pedodontics].

The special examination of occlusion in the gnathological sense is less important for functional analysis in orthodontics and pedodontics. At the beginning of and during therapy, simple clinical examinations and observations provide the necessary diagnostic and prognostic information on the functioning of the individual parts of the masticatory system or their relation to each other. The clinical relevance of these findings was tested by electromyographic examinations, electronic pressure and volume measurements and tele- and cineradiographic tests. In the retention period, i.e. after therapy had been concluded, a gnathological examination was made in some cases in addition to the general functional analysis. The examination mainly centered on anatomic regions: lips, tongue, masticatory muscles, and temporomandibular joint. The following functions were examined: closing of the mouth, breathing, swallowing, speech, mandibular movements and the relation of rest position to habitual occlusion. In addition, general posture and habits like suckling and nibbling were studied.

Adult

Linear discriminant function analysis in neuropsychological research: some uses and abuses.

The present paper addressed the continued misinterpretation and misapplication of linear discriminant function analysis in neuropsychological research. Methodological problems concerning the influence of shrinkage and stepwise selection procedures on LDFA are virtually ignored and affect both the classification and inferential application of LDFA. Throughout the paper examples of potential abuses of LDFA were cited and data from a familiar research problem was employed to demonstrate procedures which enable more accurate interpretation of LDFA results. Linear discriminant function analysis and its multivariate equivalents are powerful and flexible tools for exploring group differences provided appropriate applications and interpretations of results are made.

Craniocerebral Trauma

Determination of sex by discriminant function analysis of postcranial skeletal measurements.

Thieme and Schull [16] took measurements of seven postcranial traits from black skeletons of known sex to devise a method for accurately sexing human remains. With a linear discriminant function analysis of the data they obtained a 98.5% accuracy. The research reported here was designed to assess the accuracy of their method in the hands of other investigators using a sample of the same black population and its applicability to other populations of the same and different races. None of the samples used in this study were sexed with the same rate of accuracy either achieved or predicted by Thieme and Schull. However, two samples did reach 91% or better. Such results suggest that the methods employed have considerable value if used with appropriate precautions. Our multiple discriminant function analysis strongly indicates that neither side nor observer techniques affected the results. Sex accounts for a predominant fraction of the total variation among samples and race accounts for most of that remaining.

Anthropometry

Applying functional analysis to psychological rehabilitation following spinal cord injury.

There have been numerous attempts to categorize the responses of individuals to spinal trauma on the basis of generalized stage theories of grief reaction, and personality theory. A number of these studies are critically appraised and a behavioral model, based on functional analysis, is proposed as a more constructive framework for future research. Such an approach is applied clinically to the activities and development of the Clinical Psychology Service provided to the Mersey Regional Spinal Injuries Centre in Southport, England. A number of examples of clinical and research practice are included, highlighting the applicability of functional analysis to individual and systems level investigations.

Adaptation, Psychological

[Functional analysis in stomatology].

A survey of diagnostic details is made on which functional analysis is based. Symptoms connected with the temporo-mandibular joint, muscle palpation, radiological demonstration of the temporo-mandibular joint, and registration of the positional jaw relation are especially dealt with. The methods of examination which are prerequisite to a safe diagnosis are critically evaluated.

Dental Articulators

Functional analysis of human papillomavirus type 16 E7 by complementation with adenovirus E1A mutants.

Functional analysis of human papillomavirus type 16 E7 protein by complementation with adenovirus E1A mutants in baby rat kidney cells has shown that the retinoblastoma gene product (RB)-binding region of E7 can substitute in trans for that of E1A. An N-terminal E7 mutant was unable to complement an E1A mutant unable to bind p300, indicating that the two mutants were defective for functionally equivalent activities. E7 proteins with mutations within the RB-binding region were also unable to complement either the non-p300-binding E1A mutant or the N-terminal E7 mutant, suggesting that these mutations affect more than just RB binding.

Adenovirus Early Proteins

Structure-function analysis of the histidine permease and comparison with cystic fibrosis mutations.

Traffic ATPases constitute a superfamily of transporters that include prokaryotic permeases and medically important eukaryotic proteins, such as the multidrug resistance P-glycoprotein and the cystic fibrosis gene product. We present a structure-function analysis of a member of this superfamily, the prokaryotic histidine permease, using mutations generated both in vitro and in vivo, and assaying several biochemical functions. The analysis supports a previously predicted structural model and allows the assignment of specific functions to several predicted structural features. Mutations in the secondary structure features which form the nucleotide-binding pocket in general cause the loss of ATP binding activity. Mutations in the helical domain retain ATP binding activity. Several mutations have been identified which may affect the signaling mechanism between ATP hydrolysis and membrane translocation. We relate our findings to those emerging from the recent biochemical and genetic analyses of cystic fibrosis mutations.

ATP-Binding Cassette Transporters

A brief functional analysis of aggressive and alternative behavior in an outclinic setting.

We conducted a brief functional analysis to identify maintaining variable for aggressive behavior and an alternative replacement response during a 90-min outpatient evaluation of 3 individuals with severe handicaps. During the initial analogue assessment, which focused on identifying maintaining contingencies for aggressive behavior, each participant displayed a substantially greater frequency of aggressive behavior during one condition than during any other. The contingency that produced the highest percentage of aggressive behavior was then presented for the occurrence of a specific alternative behavior (a mand). During this contingency reversal phase, each participant displayed a substantial reduction in aggressive behavior and a substantial increase in alternative behavior, thus providing a direct analysis of the equivalency of the contingency for maintaining either behavior.

Adult

Functional analysis of the expression of the 3'-phosphoglycerate kinase pgk gene in Aspergillus nidulans.

A functional analysis of the Aspergillus nidulans 3-phosphoglycerate kinase pgk promoter was undertaken using gene fusions to the lacZ gene of Escherichia coli, and introducing these into a beta-galactosidase-deficient strain of A. nidulans. Expression of a particular gene fusion in transformed strains depends upon the site of integration of the vector into the genome, and when specifically targeted to the catabolic quinate dehydrogenase qutE (selective marker) locus is directly proportional to its copy number. The analysis of transformed strains with single copies of pgk promoter deletion--lacZ fusions at the qutE locus identified three constitutive, positively acting sequence elements in the pgk gene. Sequence located between -161 and -120 nucleotides relative to the transcript start site +1, and including an element with a seven-out-of-eight nucleotide match (AAGCAAAT; -131 to -124) to the consensus eukaryotic octamer sequence ATGCAAAT, is essential for expression, and deletion of the complete 41-nucleotide sequence abolishes transcription. Sequence encompassing codons 14 to 183 and including the two introns of pgk contributes approximately one-third of the total activity, and far upstream sequence 5' to position -638 contributes approximately a further one-third total activity. In addition, sequence located -638 to -488 nucleotides, which includes an apparent consensus feature of A. nidulans glycolytic genes, affects carbon source-dependent regulation of expression. This region is required for an approximately 50% increase in pgk expression when A. nidulans is grown on gluconeogenic compared with glycolytic carbon sources.

Aspergillus nidulans

Phenotypic and functional analysis of lamina propria mononuclear cells from colonoscopic biopsy specimens in patients with ulcerative colitis.

Phenotypic and functional analysis was performed with lamina propria mononuclear cells (LPMCs) isolated from colonoscopic biopsies in 27 patients with ulcerative colitis (UC). The proportion of T lymphocytes displaying HLA-DR antigens, interleukin 2 (IL-2) receptor, and transferrin receptor was greater in active UC than in control diseases. When LPMCs were cultured with IL-2 or phytohemagglutinin for 72 h, there were no significant differences in the proportion of cells bearing these activation markers between active UC and controls. The proportion of CD56+ cells and lymphokine-activated killer (LAK) cell activity was lower in LPMCs from active UC than in control cells, and depletion of CD56+ cells from control lamina propria cells essentially eliminated LAK cell activity. Mucosal T lymphocytes may be activated in vivo during active inflammation in UC, and lower levels of intestinal LAK cell activity may be related to the decrease of CD56+ cells under these conditions.

Adolescent

Functional analysis of Histoplasma capsulatum-reactive T-cell hybridomas.

Activation of CD4+ T cells is a crucial step in the elimination of Histoplasma capsulatum yeast cells from tissues. However, only a limited amount of information exists concerning the immunobiology of H. capsulatum-reactive T cells that are CD4+. To facilitate the analysis of the functional activities of this T-cell subpopulation, we developed a panel of 10 murine T-cell hybridomas from splenocytes of immune C57BL/6 mice. All hybridomas reacted with monoclonal anti-CD4+ antibody and released interleukin-2 after stimulation with histoplasmin. Within 3 weeks, the reactivity of hybridomas to histoplasmin declined dramatically, yet the cells responded vigorously to yeast-phase preparations that were enriched for cytosol, cell wall, or cell membrane. Of 10 hybridomas studied, only one recognized heterologous fungal antigens. Responsiveness to yeast-phase antigens was restricted by I-Ab. We mapped determinants in cytosol and cell wall or cell membrane by the technique of one-dimensional T-cell immunoblotting. The patterns of responses of hybridomas to cytosol were nearly uniform. All hybridomas responded to two immunodominant regions in cytosol with masses ranging from less than or equal to 18 to 26 kilodaltons (kDa) and 35 to 39 kDa. All hybridomas tested responded to determinants in the cell wall or cell membrane preparation with masses of 35 to 39 kDa. These hybridomas provide a useful tool for defining yeast-phase antigens that trigger T-cell activation.

Animals

Functional analysis of HIV-1 reverse transcriptase amino acids involved in resistance to multiple nonnucleoside inhibitors.

Several novel, structurally distinct classes of specific human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) nonnucleoside inhibitors have been described recently. These include the pyridinone derivatives L-697,639, L-697,661, and L-696,229 as well as BI-RG-587 and the tetrahydroimidazo[4,5,1-j,k]-benzodiazepin-2(1H)-one and -thione compounds. Previous studies have implicated involvement of the RT amino acid residues at positions 103, 181, and 188 in the activity of the compounds. Accordingly, HIV-1 RT mutants containing a series of amino acid substitutions at these positions were constructed. The relative resistance of purified mutant enzymes to each of the inhibitors was assessed. This analysis established the functional equivalence of the three inhibitor classes and provided evidence for the interaction of the 103 site with the 181/188 region. Amino acid substitutions at these positions were also found to influence RT sensitivity to inhibition by phosphonoformate, thereby suggesting a close association between this pyrophosphate analog's binding site in RT and the binding site of the nonnucleoside inhibitors. In addition, aromatic stacking of the amino acid side groups at residues 181 and 188 was suggested to be required for inhibitor activity.

Amino Acid Sequence

[Comparative clinical study of 3 technics of functional analysis of occlusion].

The object of our research is to compare clinically and objectively three articulators: -- the Dentatus, semiadjustable articulator which employs dynamico-static records -- the T.M.J., fully adjustable articulator which employs dynamico-cinematic stereographic endobuccal records -- the Denar, fully adjustable articulator which employs dynamico-cinematic pantographic extrabuccal records. We expressly avoided repeating the mechanical and mathematical analysis of the possibilities and limitations of the articulator and copying the previous researches which always imply quasi-perfection in the behaviour of the patient, in the manipulations of the dental surgeon and in the physical qualities of the articulator and materials used. Our comparative research claims to respect all the variables which occur in the carrying out of an actual case and which are inherent in the patient, the dental surgeon, the articulator and the materials used. In carrying out our research we followed two essential conditions: -- We decided to follow, first of all, a strictly clinical plan using successively the three articulators in the analysis of the occlusal function (carried out twice) for each of the six patients and comparing the results obtained for each articulator and for each patient. -- We decided, next, that this comparative research should be strictly objective. To this end, we did not set out to form an opinion, on the basis of clinical impressions, favourable or unfavourable to the different characteristics of the three articulators. We limited ourselves, on the contrary, to measuring, superposing and making a comparative analysis of the results obtained with the three articulators for the same analysis of the occlusal function.

Dental Arch