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PubMed1999

Measurement of obesity by anthropometry and bioelectric impedance analysis: correlation with fasting lipids and insulin resistance in an Asian population.

Obesity is associated with increased coronary artery disease risk. This is at least partially mediated by increased prevalence of other risk factors such as dyslipidaemia and insulin resistance. Various anthropometric indices have been used to quantify generalised and central obesity. Correlations between these measurements and risk factors are specific to the population and findings cannot be extrapolated to other ethnic groups. Bioelectric impedance analysis (BIA) is a simple means of estimating percentage body fat. We compared body mass index (BMI), waist circumference, waist-hip ratio (WHR) and percentage body fat measure by BIA as predictors of fasting lipid profiles and insulin resistance in 109 Singaporean Chinese. BMI was significantly correlated with insulin resistance and there appeared to be a threshold at 26 kg/m2 above which the regression line became more steep. WHR best predicted fasting triglyceride in both men and women. In women, it was inversely correlated with high density lipoprotein cholesterol. A similar association was seen in men but this did not reach statistical significance. We conclude that measurement of BMI and WHR should be part of the assessment of cardiovascular risk in our population as they connote different aspects of risk. BIA was not found to be a useful tool for the prediction of coronary artery disease risk factors in our population.

Adult↗
PubMedDate not supplied

Immunodetection of HER-2/neu protein in frozen sections evaluated by image analysis: correlation with overall and disease-free survival in breast carcinomas.

The immunodetection of HER-2/neu oncogene product was performed in 108 breast carcinomas using immunoperoxidase technique. Monoclonal anti HER-2/neu protein was applied on frozen sections. Immunoprecipitates were evaluated by a computerized system of image analysis (SAMBA). The percentage of the immunostained tissue surfaces and mean optical densities were correlated with the 5 year overall and disease-free survival rates. It was shown that in optimal conditions of antigen preservation and standardized method of immunoprecipitates evaluation, 67% of breast carcinomas were more than 20% pHER-2/neu positive. The pHER-2/neu overexpression was not significantly correlated with the overall 5 year survival. However large positive anti pHER-2/neu surfaces were correlated with higher risk of recurrence (p = 0.0013) and of metastases (p = 0.035).

Adult↗
PubMed1977

Intrafamilial correlation analysis for IgM serum levels.

The IgM serum level was determined in the members of 29 healthy families. The IgM mean concentrations between fathers and mothers and between sons and daughters were significantly different (P less than .01), with higher serum IgM levels in females than in males. Simple linear regression analysis was done for the following intrafamilial combinations: son-father, daughter-father, son-mother, and daughter-mother. Significant correlation coefficients (P less than .05) were obtained in all four combinations, which does not support the X-linked gene hypothesis (i.e., that the X chromosome carries quantitative genes for immunoglobulin M). An alternative explanation for the differences between sexes for IgM serum concentration is considered.

Adolescent↗
PubMed1996

Fluorescence correlation analysis of probe diffusion simplifies quantitative pathogen detection by PCR.

A sensitive, labor-saving, and easily automatable nonradioactive procedure named APEX-FCS (amplified probe extension detected by fluorescence correlation spectroscopy) has been established to detect specific in vitro amplification of pathogen genomic sequences. As an example, Mycobacterium tuberculosis genomic DNA was subjected to PCR amplification with the Stoffel fragment of Thermus aquaticus DNA polymerase in the presence of nanomolar concentrations of a rhodamine-labeled probe (third primer), binding to the target in between the micromolar amplification primers. The probe becomes extended only when specific amplification occurs. Its low concentration avoids false-positives due to unspecific hybridization under PCR conditions. With increasing portion of extended probe molecules, the probe's average translational diffusion properties gradually change over the course of the reaction, reflecting amplification kinetics. Following PCR, this change from a stage of high to a stage of low mobility can directly be monitored during a 30-s measurement using a fluorescence correlation spectroscopy device. Quantitation down to 10 target molecules in a background of 2.5 micrograms unspecific DNA without post-PCR probe manipulations could be achieved with different primer/ probe combinations. The assay holds the promise to concurrently perform amplification, probe hybridization, and specific detection without opening the reaction chamber, if sealable foils are used.

Automation↗
PubMed1979

Assessment of cognitive deficiency with the McCarthy Scales and Stanford-Binet: a correlational analysis.

The present study tested matched samples of 15 retarded and 15 normal children on the Stanford-Binet Intelligence Scale and the McCarthy Scales of Children's Abilities. Pearson correlations between Stanford-Binet IQs and the six McCarthy Scale Indexes for retarded subjects were lower than coefficients obtained from the normal subjects and from previous research. While the General Cognitive Index may be interchangeable with IQ in the Normal range of intellectual functioning, this relationship was not found for the retarded subjects in the present study. The "venerable" Stanford-Binet retains its position as the most broadly applicable measure of intellectual functioning. Implications of the study as well as an outline for future research were included.

Child↗
PubMed2002

The relationship between rhythmic activities during a mental task and sleep spindles: a correlative analysis.

In a previous study, we suggested that the characteristics of theta, alpha, and beta rhythms during a mental task were similar to those during sleep. Building upon the previous data, correlations between rhythmic activities during a mental task and during sleep were investigated in the present study. Patterns of correlation and no correlation between rhythmic activities during the mental task were similar to those during sleep for subjects with and without frontal midline theta (Fmtheta) activity. In the Fmtheta group, there were no correlations between rhythmic activities in the two situations, while in the non-Fmtheta subjects, theta and alpha rhythms showed a positive correlation with one another, and theta and beta rhythms correlated negatively during sleep. In both groups, there were many correlations between rhythmic activities during the mental task and those in Sleep Stage 2, while there were few correlations between rhythmic activities during the mental task and those in other sleep stages. These results suggest that the mechanism generating rhythmic activities during the appearance of rhythmic activities induced by a mental task may be closely related to those of rhythmic activities during sleep, and that the membrane potentials in reticular thalamic (RE) neurons during the appearance of rhythmic activities induced by a mental task may be nearly equivalent to that in Sleep Stage 2, and that the correlation pattern between the rhythmic activities in each group may be well explained by the appearance pattern of each rhythm in the previous report.

Adult↗
PubMed1983

Synthesis, biological data and correlation analysis in a set of analgesic drugs.

A set of ortho-disubstituted benzene derivatives (2-X--C6H4NH--Y) designed as analgesics has been studied. Some physicochemical properties which are potentially correlated with the considered pharmacological activities are determined. Quantitative structure-activity relationships (QSAR) show that the analgesic potency (writhing test) is a function of the hydrophobic-lipophilic parameters associated with the structures under study. Since the derivatives are inactive or very poor inhibitors of prostaglandin biosynthesis, the appropriate modulation of substituents may maximize the differentiation between anti-nociceptive and analgesic activity.

Acetates↗
PubMed1999

[Correlation analysis of (G + C)% of coding sequence and thermostability of xylose isomerase of thermophiles].

Statistical analysis about amino acids and coding sequence of xylose isomerase were performed in a number of thermophiles and mesophiles. It was found that there are correlations between the (G + C)% of the coding sequence and that of 1st, 2nd and 3rd position of the code of amino acids. There were also positive (for hydrophobic amino acids) and negative (for hydrophilic amino acids) correlation between the content of individual amino acids in the enzyme protein and the (G + C)% of their respective coding sequence. It speaks for the notion that high content of (G + C) in the coding sequence tends to increase the thermostability of the corresponding protein. The results in the statistical analysis of amino acid substitutions leading to change in thermostability of the protein may also be interpreted in the same way. An increase in the (G + C)% of DNA of a bacterium can therefore not only increase the thermostability of DNA itself but its proteins as well. Evolutionary consequence concerning thermophily and coding system are discussed.

Aldose-Ketose Isomerases↗
PubMed2002

Multiparametric MRI ISODATA ischemic lesion analysis: correlation with the clinical neurological deficit and single-parameter MRI techniques.

BACKGROUND AND PURPOSE: The purpose of this study was to show that the computer segmentation algorithm Iterative Self-Organizing Data Analysis Technique (ISODATA), which integrates multiple MRI parameters (diffusion-weighted imaging [DWI], T2-weighted imaging [T2WI], and T1-weighted imaging [T1WI]) into a single composite image, is capable of defining the ischemic lesion in a time-independent manner equally as well as the MRI techniques considered the best for each phase after stroke onset (ie, perfusion weighted imaging [PWI] and DWI for the acute phase and T2WI for the outcome phase). METHODS: We measured MRI parameters of PWI, DWI, T2WI, and T1WI from patients at the acute phase (<30 hours) and DWI, T2WI, and T1WI at the outcome phase (3 months) of ischemic stroke. The clinical neurological deficit was graded with the National Institutes of Health Stroke Scale (NIHSS). We compared the ISODATA lesion size with the PWI, DWI, and T2WI lesion sizes measured within the same slice at each phase. The lesion sizes were also correlated with NIHSS score of each phase. RESULTS: We included 11 patients; 9 (82%) were women, and 7 (64%) were black. The mean+/-SD age was 65.5+/-9.3 years (range, 45 to 82 years). The median NIHSS score was 15 (minimum, 4; maximum, 24)at the acute phase and 3 (minimum, 0; maximum, 22) at the outcome phase. The median time interval from stroke symptom onset to the acute MRI study was 10 hours (range, 6 to 29 hours), and the mean time interval to the outcome study was 93+/-11 days (range, 72 to 106 days). In the acute phase, the ISODATA lesion size had high correlation with the PWI lesion size (r=0.95; 95% CI, 0.89 to 0.98; P<0.0001), DWI lesion size (r=0.83; 95% CI, 0.66 to 0.92; P<0.0001), and T2WI lesion size (r=0.67; 95% CI, 0.39 to 0.84; P=0.008) and moderate correlation with NIHSS score (r=0.59; 95% CI, 0.02 to 0.88; P=0.06). In the outcome phase, the ISODATA lesion size had high correlation with the T2WI lesion size (r=0.97; 95% CI, 0.94 to 0.99; P<0.0001) and NIHSS score (r=0.78; 95% CI, 0.34 to 0.94; P=0.004). CONCLUSIONS: The integrated ISODATA method can identify and characterize the ischemic lesion independently of time elapsed since stroke onset. The ISODATA lesion size highly correlates with the PWI and DWI lesion size in the acute phase and with the T2WI lesion size in the outcome phase of ischemic stroke, as well as with the clinical neurological status of the patient.

Aged↗
PubMed1996

[Correlation analysis of the changes of EEG mapping and the changes of CT scan in patients with senile dementia].

OBJECTIVE: To observe the changes of EEG mapping and CT scan and analyse the correlation between the changes of the function presented by EEG mapping and morphology presented by CT. METHODS: The absolute power of EEG mapping and 9 parameters of CT in 30 normal controls and 31 patients with senile dementia were measured. The correlation was analysed quantitatively with multiple stepwise regression method. RESULTS: The EEG mapping of senile dementia revealed a diffuse increase in delta, theta power and decreased alpha power in most areas. CT scan showed cortical and subcortical atrophy in brain. There were positive correlations between the increase of delta power and lateral fissure, and between the increase of delta power and average cerebral sulcus. There was a negative correlation between the decrease of alpha power and the increase of lateral fissure. CONCLUSION: The EEG mapping and CT in patients with senile dementia are different from those in normal elderly. There is a correlation between the changes of EEG mapping and CT scan.

Aged↗
PubMed1998

A frequency and correlation analysis of motor deficits in Parkinson patients.

PURPOSE: The present study explored the frequency and pattern of functional motor problems of a group of Parkinson patients, as a first step towards developing a rational approach to rehabilitation intervention addressing the primary symptoms of the disease. METHOD: Sixty patients, consisting of 40% women and 60% men with a mean age of 63.5 years and of which 88% were taking L-dopa, underwent a number of standardized clinical tests including part III of the UPDRS. They were also interviewed about the frequency of motor problems occurring at home. RESULTS: Loss of trunk rotation as expressed in rolling in supine and reduced arm swing were the most frequently registered motor disorders (73%, 75%). Freezing at the start of, or during, walking was not observed during clinical testing but was frequently claimed to occur at home (48%, 23%). A broad spectrum of deficits regarding gait, posture, transfers and distal motor problems formed a cluster, which was strongly correlated with bradykinesia (p < 0.001). Principal component analysis identified four distinct problem areas: (1) axial motor performance; (2) akinetic gait problems; (3) rigidity; and (4) tremor. CONCLUSIONS: Parkinson patients, particularly in the later stages of the disease, presented with significant levels of functional disability which was mainly linked with the underlying impairment of bradykinesia.

Adult↗
PubMed1985

Reticular formation of the lower brainstem. A common system for cardio-respiratory and somatomotor functions. Cross-correlation analysis of discharge patterns of neighbouring neurones.

Temporal relations of discharges of 73 pairs of neurones located in the medial parts of the reticular formation of the lower brainstem were studied by cross correlation analyses in chloralose-urethane anaesthetized dogs. The action potentials of 2 or 3 neighbouring neurones were recorded with one electrode simultaneously. Uncorrelated discharges of neurones and 4 different types of correlated discharges were observed in cross correlation histograms: they were: (1) rhythmic couplings with frequencies between 2 and 5 Hz related to the same rhythm in the EEG; (2) strong, non-rhythmic couplings with short latencies up to 5 ms; (3) a combination of strong and rhythmic couplings, and (4) high-frequency oscillation couplings. Most pairs of neurones showed different types of correlation during the recordings. The different forms of correlated discharge behaviour could be related to different types of functional organization of the neuronal network in the reticular formation.

Afferent Pathways↗
PubMed2003

Image analysis measurements of roughness by texture and fractal analysis correlate with contact profilometry.

Surface properties of a biomaterial are important factors that govern in part its biocompatibility. Among them, surface roughness is now recognized as a very important factor for cell interactions. Surface roughness (Ra) is routinely measured by contact profilometry but other methods are presently usable. We compared two methods (contact profilometry and image analysis of scanning electron microscopic images SEM) on a series of 12 titanium test pieces. The texture analysis of SEM pictures was done by the heterogeneity and run-length methods. Fractal geometry was also used with the "skyscraper" and "blanket" methods providing respectively the D(SKY) and D(BLANK) fractal dimensions. The fractal dimension of the profilometric curve was also computed (D(MINK)). Computer-simulated textures were used to evaluate the pertinence of the algorithms. A significant correlation was found between Ra and all the texture descriptors except heterogeneity. The correlation coefficient was dependent on the microscopic magnification. The fractal dimension of the curve was correlated with D(SKY) and D(BLANK). Run-length, D(SKY) and D(BLANK) were highly correlated, independent of the magnification used, a finding related to the self-similarity of the images. Image texture analysis can be a useful alternative to profilometry with brittle or soft materials or with objects having a complex shape.

Algorithms↗
PubMedDate not supplied

Pulse oximeter in the neonatal ICU: a correlational analysis.

In critically ill neonates the risk associated with rapid changes in oxygen saturation is high. Thus effective means of monitoring blood oxygen saturation is essential. While pulse oximetry is appealing because it is noninvasive and in general it correlates well with arterial blood gases (ABG), some concerns remain about its accuracy in certain circumstances. An extensive review of the literature of pulse oximetry revealed several conditions in adults that may affect the accuracy, including: anemia, low pulse pressure, and elevated lipids. Less research has been done with children and neonates. This study examined pulse oximetry and ABG values in critically ill neonates. Ninety-three sampling events were used to examine the effects of the following variables on the accuracy of pulse oximetry in the neonate: gestational age, chronological age, diagnosis, anemia, hyperbilirubinemia, hyperalimentation, lipid infusions, inotropic agents. For several of these variables (anemia, hyperbilirubinemia, hyperalimentation, lipid infusion, inotropic drugs), correlations between pulse oximetry and ABG values were low, raising concerns about the use of pulse oximetry in the critically ill neonate.

Adult↗
PubMed2005

Correlative analysis on the relationship between PMI and DNA degradation of cell nucleus in human different tissues.

To determining the postmortem interval (PMI) through quantitative analysis of the DNA degradation of cell nucleus in human brain and spleen by using image analysis technique (IAT). The brain and spleen tissues from 32 cadavers with known PMI were collected, subjected to cell smear every 1 h within the first 5-36 h after death, stained by Feulgen-Van's staining, Three indices reflecting DNA in brain cells (astrocytes) and splenic lymphocytes, including integral optical density (IOD), average optical density (AOD), average gray (AG) were measured by employing the mage analysis instrument. The results showed that IOD and AOD declined and AG increased with the prolongation of dead time within 5-36 h. A correlation between the PMI and gray parameters (IOD, AOD and AG) was identified and the corresponding regression equation was obtained. The parameters (IOD, AOD and AG) were proved to be effective quantitative indicators for accurate estimation of PMI within 5-36 h after death.

Cell Nucleus↗
PubMed2006

[Correlative analysis between HLA high resolution typing and GVHD in 48 cases received unrelated umbilical cord blood transplantation].

Unrelated umbilical cord blood units for 54 cases in 21 transplant centers were provided by Guangzhou Cord Blood Bank in China from 1998 to 2003. This study was aimed to identify HLA-DRB1 alleles by means of PCR sequencing based typing methods (SBT) and to analyze the correlation between HLA-DRB1 alleles and GVHD in unrelated umbilical cord blood transplantation (UCBT). 48 out of 54 patients received UCBT were followed up. DNA were extracted from cryopreservation blood of recipients/donors with UCBT, HLA-DRB1 alleles typing were done by SBT. Compared with low resolution results of HLA-DRB1 alleles, high resolution results were analyzed to see any correlation between HLA-DRB1 alleles and GVHD. by double-blind statistically analysis of HLA-DRB1 high resolution in 48 donor/recipient typings in UCBT. The results showed that the incidence of GVHD (25%) in patients who has HLA-DRB1 alleles matched with donors significantly lower (65.6%) than that in the patients with HLA-DRB1 alleles mismatched (P = 0.008). It is concluded that HLA-DRB1 by high resolution typing method is important in clinical application in UCBT.

Alleles↗
PubMed1995

Fluctuation and cross-correlation analysis of protein motions observed in nanosecond molecular dynamics simulations.

Nanosecond molecular dynamics simulations of bovine pancreatic trypsin inhibitor and lysozyme in water are analyzed in terms of backbone atomic positional fluctuations and dynamical cross-correlations. It is found that although the molecular systems are stable, B-factors calculated over a time period as long as 500 ps are not representative for the motions within the proteins. This is especially true for the most mobile residues. On a nanosecond time-scale, the B-factors calculated from the simulations of the proteins in solution are considerably larger than those obtained by structure refinement of the proteins in crystals, based on X-ray data. The time evolution of the atomic fluctuations shows that for large portions of the proteins under study, atomic positional fluctuations are not yet converged after a nanosecond. Cross-correlations do not converge faster than the fluctuations themselves. Most display very erratic behavior if the sampling covers less than about 200 ps. It is also shown that inclusion of mobile atoms into the procedure used to remove rigid-body motion from the simulation can lead to spurious correlations between the motions of the atoms at the surface of the protein.

Animals↗