SEARCH · PubMed Health

Results for “global functioning”

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 1,477 records · Page 82Linked to original sources

PubMed1986

Association and transfer functions for analysis of drug binding to proteins.

A global association function is proposed that characterizes the apparent overall equilibrium of drug protein binding. It is defined as a function of the total drug concentration and may be directly calculated from each experimental result. The binding transfer function represents the relative rates of change in the bound and free concentrations from the total concentration. Two applications are presented: one is an investigation of the effect of temperature on binding of salicylic acid to proteins in plasma; and the other is a comparison of the phenomenon in two different biological fluids (protein binding of sodium salicylate in plasma and in synovial fluid).

Blood Proteins↗

PubMed2000

lazarus is a novel pbx gene that globally mediates hox gene function in zebrafish.

Individual vertebrate Hox genes specify aspects of segment identity along the anterior-posterior axis. The exquisite in vivo specificity of Hox proteins is thought to result from their interactions with members of the Pbx/Exd family of homeodomain proteins. Here, we report the identification and cloning of a zebrafish gene, lazarus, which is required globally for segmental patterning in the hindbrain and anterior trunk. We show that lazarus is a novel pbx gene and provide evidence that it is the primary pbx gene required for the functions of multiple hox genes during zebrafish development. lazarus plays a critical role in orchestrating the corresponding segmentation of the hindbrain and the pharyngeal arches, a key step in the development of the vertebrate body plan.

Animals↗

PubMed1998

Gene expression screening in Xenopus identifies molecular pathways, predicts gene function and provides a global view of embryonic patterning.

In a large-scale gene expression screen 1765 randomly picked cDNAs were analyzed by whole-mount in situ hybridization in Xenopus embryos. Two hundred and seventy three unique, differentially expressed genes were identified, 204 of which are novel in Xenopus. Partial DNA sequences and expression patterns were documented and assembled into a database, 'AXelDB'. Approximately 30% of cDNAs analyzed represent differentially expressed genes and about 5% show highly regionalized expression. Novel marker genes and potential developmental regulators were found. Differential expression of mitochondrial genes was observed. Marker genes were used to study regionalization of the entire gastrula as well as the tail forming region and the epidermis of the tailbud embryo. Four 'synexpression' groups representing genes with shared, complex expression pattern that predict molecular pathways involved in patterning and differentiation were identified. According to their probable functional significance these groups are designated as Delta1, Bmp4, ER-import and Chromatin group. Within synexpression groups, a likely function of genes without sequence similarity can be predicted. The results indicate that synexpression groups have strong prognostic value. A cluster analysis was made by comparing gene expression patterns to derive a novel parameter, 'tissue relatedness'. In conclusion, this study describes a semi-functional approach to investigate genes expressed during early development and provides global insight into embryonic patterning.

Animals↗

PubMed1991

Models of coronary artery disease: "critical" versus "functional" coronary artery stenosis.

"Critical coronary stenosis" (reduction of coronary blood flow [Q] until reactive hyperaemia following 15s coronary occlusion is just abolished) and "functional stenosis" (reduction of Q until systolic shortening (dL) of post-stenotic myocardium is curtailed by 50%) were compared with respect to the reduction in Q necessary and the effect on regional myocardial and global ventricular function. In 9 anaesthetized (piritramide) dogs, enddiastolic length (edL) and dL of a myocardial area supplied by the left descending coronary artery (LAD) were measured by sonomicrometry. Left-ventricular end-diastolic pressure (LVEDP) and dP/dt, aortic pressure (AoP), stroke volume (SV), and heart rate (HR) were monitored. QLAD was stepwise reduced by a snare. Critical stenosis, present at a 25% reduction of QLAD, had no effect on regional and global ventricular function, but recovery of dL after release of 15s LAD occlusion was significantly delayed. Further obstruction of QLAD progressively impaired dL, reaching 50% dL (functional stenosis) by a flow reduction of about 50%. The decrease in dL was accompanied by an increase in edL. The haemodynamic effects of the functional stenosis were rather discrete (LVEDP + 5%, SV-12%, dP/dtmax-8%). Models of myocardial ischaemia used to study the effect of drugs or other haemodynamically effective interventions should be able to show functional impairment as well as improvement of the ischaemic myocardium. The critical stenosis does not impair myocardial function and, consequently, a favourable influence on the function and, consequently, a favourable influence on the function of ischaemic myocardium by any intervention may not become evident. However, in the presence of a functional stenosis the change in systolic shortening of the ischaemic myocardium is a very sensitive response to any intervention which affects the energy balance of the ischaemic myocardium. Therefore, this model should be preferred.

Animals↗

PubMed1986

[Radionuclide ventriculographic evaluation of left ventricular systolic function in acute myocardial infarction].

Within 18 hours of acute myocardial infarction, global left ventricular (LV) function was evaluated by radionuclide ventriculography for 127 patients. Ejection fraction (EF) was calculated using a variable region of interest counts method. LV end-diastolic volume index (EDVI) was calculated from the LV outlines in the anterior and LAO projections using the area-length method. To validate the determination of EDV by the area-length method, the radionuclide EDV correlated with that derived from direct contrast angiography in 44 other patients who had both studies within two weeks, with an overall correlation coefficient of 0.84. To minimize any potential problems with the geometric ellipsoid model, the end-systolic volume index (ESVI) was calculated from EF and EDVI. Peak systolic blood pressure (PSP) was recorded with a cuff during imaging and the PSP/ESV calculated as a measure of LV contractile function. The regional wall motion of five segments in both the anterior and LAO projections were each scored on a scale, from 4 (= normal) to 0 (= dyskinesis). The wall motion index (WMI) derived from the sum of the 10 segment scores represented an overall index of wall motion (maximum = 40). In addition, the more widely used % abnormally contracting segments (%ACS) was calculated. The severity of wall motion abnormalities were associated with significant increases in heart rate and ESVI, whereas EDVI began to increase under more severe damage to the myocardium. Our data are consistent with those of Klein who found that the LV enlarges only when 20 to 25% of the surface area is rendered akinetic. There were significant decreases in EF and PSP/ESV with moderate reduction in wall motion, and the relation between EF and PSP/ESV was curvilinear. Information about ventricular volume and systolic blood pressure might be of additional value to EF for a more complete understanding of the changes in the functional state of the LV. Global LV function was compared between anterior and inferior myocardial infarcts. The size of %ACS was larger in anterior than in inferior infarction and a greater decrease in WMI in the former suggested larger infarct size in anterior infarction. As a result, ESVI was significantly larger in anterior infraction than in anterior infraction. However, an increase in EDVI was not significantly different between the two groups. EF was reduced to a greater extent in anterior than in inferior infarction. The overall data indicate that patients with anterior infarction have more severe impairment of left ventricular global function than do those with inferior infarction.

Cardiac Volume↗

PubMed2005

Modified TEI index: a promising parameter in essential hypertension?

PURPOSE: Modified TEI index is pointed to be more effective in the evaluation of global cardiac functions compared to systolic and diastolic measurements alone. We planned to determine its applicability in hypertension and relation with left ventricular mass index (LVMI). METHODS: We studied 48 patients with mild/moderate hypertension and normal coronary angiograms. In total 22 patients (12 men, 10 women, mean age: 55 +/- 6) with normal LVMI were studied in group I, 26 patients (12 men, 14 women, mean age: 57 +/- 7) with increased LVMI in group II, and 20 patients (10 men, 10 women, mean age: 53 +/- 7) with normal blood pressure as a control group. Standard 2D, Doppler, and mitral annulus pulse wave tissue Doppler were used for all measurements. Modified TEI index was calculated as diastolic time interval measured from end of Am wave to origin of Em (a') minus systolic Sm duration (b') divided by b(a'-b'/b'). RESULTS: Modified TEI index was significantly higher in both groups than normal group and in group II than in group I. ( CONTROL GROUP: 0.33 +/- 0.05, group I: 0.51 +/- 0.17, group II: 0.68 +/- 0.16, P< 0.0001). CONCLUSION: Modified TEI index, a marker of left ventricular systolic and diastolic functions, is impaired in hypertensives before hypertrophy develops and impairment is more prominent in hypertrophy. Therefore, (1) modified TEI index in hypertensives is a safe, feasible, and sensitive index for evaluation of global ventricular functions. (2) Evaluation of hypertensives with this index periodically may guide interventions directed toward saving systolic and diastolic functions. (3) Modified TEI index is gaining importance as a complementary parameter to standard Doppler or in cases where standard Doppler has its limitations.

Adult↗

PubMed1979

Multiple-baseline analysis of a token economy for psychiatric inpatients.

Twelve behaviors selected for reinforcement among 16 chronic psychiatric inpatients were divided into four classes: (a) personal hygiene, (b) personal management, (c) ward work, and (d) social skills. A token economy program was introduced for each class in a sequential, cumulative, multiple-baseline format. Corrections were included for methodological deficiencies frequently enountered in past studies. Treatment variables were systematically monitored, and target behavior rates, levels of global individual functioning, general ward behavior, and off-ward behavior were assessed during baseline, implementation, and probe periods. Results indicated abrupt and substantial increases in performance of most target behaviors, significant improvements in global individual functioning (p less than .025), positive changes in general ward behavior, and increases in social interaction during off-ward activities. The findings provide strong evidence for the efficacy of a token economy and indicate that the multiple-baseline design can be a useful method for evaluating token economy programs.

Activities of Daily Living↗

PubMed2005

Effect of tendon transfers and extra-articular soft-tissue balancing on glenohumeral development in brachial plexus birth palsy.

BACKGROUND: Persistent muscle imbalance and soft-tissue contractures can lead to progressive glenohumeral joint deformity in patients with brachial plexus birth palsy. The objective of this investigation was to determine the effects of correction of external rotation weakness and internal rotation contractures with tendon transfers and extra-articular soft-tissue releases on glenohumeral development in patients with brachial plexus birth palsy. METHODS: Twenty-five patients with brachial plexus birth palsy who underwent latissimus dorsi and teres major tendon transfers to the rotator cuff-with or without concomitant musculotendinous lengthenings-were evaluated clinically and radiographically before the operation and at a minimum of two years (average, forty-three months) postoperatively. Shoulder function was prospectively assessed with use of the modified Mallet classification system, in which aggregate shoulder function is assigned a score of 5 to 25 points. Glenoid version and humeral head subluxation were quantified with magnetic resonance imaging or computed tomography, and glenohumeral deformity was graded. RESULTS: Clinically, all patients demonstrated improved global shoulder function, with the mean aggregate Mallet score improving from 13 points preoperatively to 18 points postoperatively (p < 0.01). As seen radiographically, the mean glenoid retroversion improved from 22 degrees preoperatively to 16.5 degrees postoperatively (p = 0.012). The mean posterior humeral head subluxation improved from 30% to 37% (p = 0.03). No patient had progressive worsening of the glenohumeral deformity. CONCLUSIONS: Latissimus dorsi and teres major tendon transfers to the rotator cuff, combined with appropriate extraarticular musculotendinous lengthenings, significantly improved global shoulder function but led to only modest improvements in glenoid retroversion and humeral head subluxation. No profound glenohumeral remodeling occurs after these extra-articular rebalancing procedures, even when they are performed in patients of a young age. While the long-term clinical and radiographically apparent effects at skeletal maturity are uncertain, soft-tissue rebalancing procedures alone were found to have halted the progression of, but not to have markedly decreased, glenohumeral dysplasia at the time of a two to five-year follow-up.

Adolescent↗

PubMed1993

[How to assess dysfunction of the left ventricle after myocardial infarction with Doppler echocardiography].

Doppler echocardiography is one of the most useful non-invasive methods of cardiac imaging in patients who have suffered myocardial infarction because it provides important information such as the immediate identification of the infarct, its size, possible mechanical complications and an assessment of its effects on global ventricular function, all in a single procedure. Several mathematical formulae have been proposed to quantify global left ventricular function from two-dimensional imaging; the most commonly used are the surface-length method based on the parasternal short axis view (V = 5/6 A.L) and reconstruction by Simpson's method based on two orthogonal apical views. Hemodynamic data may be obtained by Doppler studies, especially of the ejection phase (transaortic velocities and cardiac output determination) and left ventricular filling. The effects of left ventricular dysfunction on the right heart may be evaluated when tricuspid regurgitation is present as right ventricular and pulmonary artery systolic pressures can be determined. The non-invasive nature of Doppler echocardiography enables documentation of these parameters of ventricular function as often as the patient's clinical status requires during follow-up, or to assess the effects of treatment in the post-infarction period.

Echocardiography, Doppler↗

PubMed2005

The relationship among insight, cognitive function of patients with schizophrenia and their relatives' perception.

Medically, insight is a multidimensional concept. Results of previous studies are inconclusive regarding the relationship between insight and global and cognitive functions. The aim of this study was to evaluate the relationship among insight, patients' global function, cognitive function of patients with schizophrenia and their key caregivers' perception about this disorder. Thirty-one patients with schizophrenia were recruited. Cognitive function such as memory index proved to be a significant predictor for patients' insight; environmental factors such as caregivers' perception was not. In addition to cognitive deficit, whether the other factors such as genetic variability, medication use, environmental factors, and illness severity, etc., could influence insight of patients will still be a controversial issue. Further multidimensional survey of the relationship with insight in a larger and comprehensive design is necessary.

Adult↗

PubMed2005

Global approach to perinatal medicine: functional genomics and proteomics.

Functional genomics (transcriptomics and proteomics) is a global, systematic and comprehensive approach to the identification and description of the processes and pathways involved in normal and abnormal physiological states. The functional genomics methods most applied today are DNA microarrays and proteomics methods, primarily two-dimensional gel electrophoresis coupled with mass spectrometry. To date, interesting research has been carried out, representing milestones for future implementation of functional genomics/proteomics in perinatal medicine. For instance, possible biomarkers of pre-eclampsia, preterm labor and gestational trophoblastic diseases have been discovered. Further systematic examination of differentially regulated genes and proteins in maternal and fetal tissues and fluids will be required. However, high-throughput technologies reflect biological fluctuations and methodological errors. Large amounts of such different data challenge the performance and capacity of the statistical tools and software available at present. Further major developments in this field are pending and the intellectual investment will certainly result in clinical advances.

Female↗

PubMedDate not supplied

Adaptive blood pool segmentation in three-dimensions: application to MR cardiac evaluation.

MRI is an established method of imaging the cardiac blood pool in four dimensions and evaluating global cardiac function. However, segmentation of the cardiac blood pool from the myocardial wall continues to be a time-consuming task and is operator dependent. This has hampered the widespread use of cardiac MRI in evaluating global cardiac function. We propose the use of an adaptive threshold-based, three-dimensional region-growing technique to segment the cardiac blood pool from the myocardium and to compute left ventricular blood volumes. It uses a unique double segmentation approach incorporating information from the myocardium to help better detect the edges of the blood pool. The adaptive threshold segmentation technique was evaluated on four human subjects by comparing with manual segmentation. Further, it requires minimal operator input and is robust and user friendly. The conclusion is that adaptive thresholds and a multidimensional region-growing approach is an appropriate method to segment the left ventricular blood pool.

Adult↗

PubMed1985

The effects of Valsalva maneuver on global and segmental left ventricular function in presence and absence of coronary artery disease.

To determine the effects of the Valsalva maneuver on global and regional left ventricular function, single-plane left ventriculograms were performed in the 30-degree right anterior oblique projection in 50 patients during normal breath holding and during the late strain phase of the Valsalva maneuver. Thirty-one patients had significant coronary artery disease (greater than 70% luminal narrowing in a major coronary artery). Ventriculograms were analyzed for determination of ejection fraction, end-diastolic, and end-systolic volumes. Regional wall motion was analyzed by a chord method of calculating segmental fractional shortening. Ejection fraction increased significantly in the entire group of patients (62 +/- 16% to 70 +/- 19%, p less than 0.0001), while both end-diastolic (105 +/- 33 cc to 88 +/- 34 cc, p less than 0.0001) and end-systolic volumes (43 +/- 29 cc to 30 +/- 29 cc, p less than 0.0001) showed striking reductions with Valsalva maneuver. Patients without significant coronary disease usually exhibited global augmentation in left ventricular function, while those with coronary disease often exhibited only segmental improvement. This augmentation appeared to be dependent on the patency of the supplying coronary vessel.

Adult↗

PubMed1993

Postischemic deterioration of sarcoplasmic reticulum: warm versus cold blood cardioplegia.

Impaired cardiac sarcoplasmic reticulum (SR) function, as evidenced by reduced SR Ca2+ uptake rate and decreased SR Ca(2+)-adenosine triphosphatase activity, has been found in postischemic "stunned" myocardium and in hearts subjected to hypothermic arrest. In this study, we compared the effects of retrograde continuous coronary sinus warm blood cardioplegia (WBC) and retrograde intermittent cold blood cardioplegia (CBC) on cardiac SR function and postischemic ventricular functional recovery in pig hearts. Twelve in situ isolated pig hearts supported by cardiopulmonary bypass were subjected to 120 minutes of cardioplegic arrest with either WBC (37 degrees C) or CBC (6 degrees to 10 degrees C), followed by 60 minutes of 37 degrees C reperfusion. Left ventricular global contractile function and coronary blood flow were measured before arrest and during reperfusion. Cardiac SR was isolated from left ventricular biopsy specimens, and 45Ca2+ uptake by SR and SR Ca(2+)-adenosine triphosphatase activity were determined. The recovery of left ventricular global contractile function as indicated by the maximum of the first derivative of left ventricular pressure was significantly improved in the WBC group compared with that of the CBC group (70% versus 46%; p < 0.05). The SR Ca(2+)-adenosine triphosphatase activity was better preserved after 60 minutes reperfusion in WBC compared with CBC (0.31 +/- 0.02 versus 0.20 +/- 0.03 microM Pi/min/mg protein, p < 0.05), and the recovery of SR Ca2+ uptake was significantly improved by WBC compared with CBC (1.15 +/- 0.12 versus 0.83 +/- 0.04 microM Ca2+/min/mg protein; p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed2005

Field theory for the global density of states distribution function of disordered conductors.

A field-theoretical representation is suggested for the electron global density of states distribution function P(nu) in extended disordered conductors. This opens a way to study the complete statistics of fluctuations. The approach is based on a functional integration over bilocal functions Psir(1)(r(2)) instead of the integration over local functions in the usual functional representation for moments of physical quantities. The formalism allows one to perform the disorder averaging and to derive an analog of the usual nonlinear sigma model-a slow functional of a supermatrix field Qr(1)(r(2))(r) approximately Psi(rr(1)) composite functionPsi (r(2)r). As an application of the formalism, the long-tail asymptotics of P(nu) is derived.

Journal Article↗

PubMedDate not supplied

Global and regional left ventricular function in heart transplant patients: an angiographic follow-up study.

We studied the global and regional left ventricular function, its determinants and its modification with time, in orthotopic heart transplant recipients. We reviewed the left ventricular cineangiography performed 1 (50 patients), 2 (33 patients), 3 (18 patients), and 4 (seven patients) years after operation. Regional wall motion was quantitatively evaluated by the area method. All patients had angiographically normal coronary arteries and no evidence of acute rejection at the time of the study. One year after heart transplantation, cardiac index and left ventricular ejection fraction were mildly but significantly lower than normal. Cardiac index was more than 2.5 L/min/m2 in all but one patient, and ejection fraction was more than 50% in all patients. Only previous acute cardiac rejection necessitating therapy and arterial hypertension showed some influence on the left ventricular function. Two years after operation, the left ventricular end-diastolic volume was increased, and left ventricular mass-volume ratio decreased compared with year 1. Three years after operation, an increase of left ventricular end-diastolic pressure and of left ventricular ejection fraction was also evident. Four years after operation, the heart rate was higher, compared with previous years. Even if the changes in the parameters of left ventricular function were significant, they were small in terms of absolute value. Regional hypokinesia was detected 1 year after heart transplantation in eight patients, involving one segment in six patients and two segments in two patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1999

Protein structure prediction by global optimization of a potential energy function.

An approach based exclusively on finding the global minimum of an appropriate potential energy function has been used to predict the unknown structures of five globular proteins with sizes ranging from 89 to 140 amino acid residues. Comparison of the computed lowest-energy structures of two of them (HDEA and MarA) with the crystal structures, released by the Protein Data Bank after the predictions were made, shows that large fragments (61 residues) of both proteins were predicted with rms deviations of 4.2 and 6.0 A for the Calpha atoms, for HDEA and MarA, respectively. This represents 80% and 53% of the observed structures of HDEA and MarA, respectively. Similar rms deviations were obtained for approximately 60-residue fragments of the other three proteins. These results constitute an important step toward the prediction of protein structure based solely on global optimization of a potential energy function for a given amino acid sequence.

Bacterial Proteins↗

PubMed1994

Early changes in left ventricular function after aortic valve replacement for isolated aortic stenosis.

To assess the immediate effects of aortic valve replacement (AVR) for valvular aortic stenosis (AS) on left ventricular (LV) systolic and diastolic function and global hemodynamics, 17 patients with AS underwent transesophageal echocardiography combined with high-fidelity LV pressure recording and thermodilution cardiac output measurements before cardiopulmonary bypass and 0.5, 6, 12, and 20 hours after AVR. Compared with results before bypass, LV systolic function had already changed 30 minutes after AVR, and remained constant thereafter: peak LV systolic wall stress decreased (from 210 +/- 60 to 130 +/- 40 g.cm-2), peak rate of dimension shortening increased (from 7.3 +/- 2.2 to 9.7 +/- 2.1 cm.s-1), both p < 0.01. Peak segmental external power thus remained constant (16.6 +/- 6.7 vs 17.7 +/- 7.6 mW.cm-3); p = NS. Changes in LV diastolic function and global hemodynamics were delayed. The peak rate of ventricular pressure decrease, normalized to developed end-systolic pressure, increased (from 15 +/- 3.2 to 19 +/- 5.2 s-1) by 6 hours. The minimal ventricular pressure of early diastole decreased (from 8.9 +/- 4.9 to 4.3 +/- 3.7 mm Hg), the peak rate of dimension lengthening of early diastole increased (from 6.0 +/- 3.0 to 8.8 +/- 2.0 cm.s-1), and LV stroke volume index increased (from 24 +/- 7 to 31 +/- 6 ml.m-2) by 12 hours, all p < 0.01. LV incoordination, defined as the dimension changes during isovolumic periods, had also improved significantly at 20 hours. Heart rate and LV enddiastolic dimension did not change.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗