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PubMed1997

Demonstration of the proliferation marker Ki-67 in renal biopsies: correlation to clinical findings.

Assessment of cell proliferation in renal biopsy samples is a potentially promising analytical tool to evaluate disease activity. So far no information is available on the correlation between proliferative activity in different anatomic compartments of the kidney and clinical symptoms. To elucidate this issue, we examined renal biopsy specimens from 20 patients with systemic vasculitis (15 Wegener's granulomatosis, five microscopic polyangiitis), 20 patients with immunoglobulin (Ig) A nephropathy (IgAN), 13 patients with minimal-change disease (MCD), 11 patients with tubulointerstitial nephritis, and five patients with diabetes mellitus. The streptavidin-biotin-peroxidase complex technique was applied to autoclave-pretreated, formalin-fixed, paraffin-embedded tissue sections to label different cell types with the antibody MIB1 directed against the Ki-67 antigen. Proliferation index (PI) was estimated as the number of positively stained nuclei per glomerular cross-section or per square millimeter section area. The interstitial cells were discriminated by additional staining of Ki-67-processed samples with specific immune markers. In patients with vasculitis, PI was considerably elevated in the extracapillary glomerular compartment (0.86), in proximal tubules (6.24), and in the interstitium (8.62). High proliferative activity was also noted in interstitium (3.98) and proximal tubules (1.35) of patients with IgAN. Of particular interest was the increased interstitial proliferative activity (15.0) in diabetic patients. Resident renal cells, but not infiltrating cells, seemed to constitute the majority of the proliferating cell population in the interstitium. In systemic vasculitis, clinical disease activity was significantly correlated to endocapillary (r(s) = 0.58), extracapillary (r(s) = 0.67), proximal tubular (r(s) = 0.67), and interstitial PI (r(s) = 0.61). By multiple linear regression analysis, proximal tubular PI was correlated to the presence of hematuria (beta = 0.72) and to interstitial fibrosis score (beta = 0.59). Interstitial PI was independently correlated to antineutrophil cytoplasmic antibodies (ANCA) titer (beta = 0.7) and interstitial fibrosis score (beta = 0.55), and it was the only one PI correlated to serum creatinine concentration (beta = 0.53). The independent association between interstitial PI and serum creatinine (beta = 0.64) was also found in IgAN. Proximal tubular PI was correlated to interstitial fibrosis score (beta = 0.59) and proteinuria (beta = 0.54). In MCD, high PI values were noted in proximal tubular cells (1.42) but not in glomeruli and the interstitium. In conclusion, assessment of proliferation activity by immunohistology provides additional information beyond conventional pathological techniques to evaluate disease activity and prognosis in renal biopsies.

Adult↗

PubMed2002

Cultural correlates of youth suicide.

Youth suicide has risen in most developed nations over the past 50 years, especially among males, but the increase remains to be explained. Statistical analyses were used to examine associations between youth suicide rates in 11-21 mainly Western, developed nations and 32 socio-economic and cultural variables. The central hypothesis was that suicide rates would be correlated with various cultural measures of social attachment and integration, especially individualism. Socio-economic variables were included in the analysis to demonstrate the relative strength of the cultural associations. The study found a strong positive correlation between male youth suicide rates and subjective measures of health, optimism, and several indices of individualism, including personal freedom and control. Correlations between female youth suicide and individualism were smaller, attaining significance in only one instance. Male youth suicide and individualism were negatively correlated with older people's sense of parental duty. Correlations between suicide and other possibly relevant cultural variables--tolerance of suicide, belief in God and national pride--were not significant. The analysis of socio-economic variables yielded only one significant, but doubtful, correlation. The findings can be interpreted as supporting two very different hypotheses: that youth suicide represents "an island of misery in an ocean of happiness" or "the tip of an iceberg of suffering". In favouring the latter interpretation, and consistent with Durkheim's theories on suicide, it is argued that increased youth suicide reflects a failure of Western societies to provide appropriate sites or sources of social identity and attachment, and, conversely, a tendency to promote unrealistic or inappropriate expectations of individual freedom and autonomy.

Adolescent↗

PubMed2001

Levels of ochratoxin A in blood from Norwegian and Swedish blood donors and their possible correlation with food consumption.

Blood levels of ochratoxin A were determined in 406 Scandinavian blood donors (206 from Oslo, Norway, and 200 from Visby on the island of Gotland, Sweden), using an HPLC method. In connection with the blood collection, the subjects were asked to fill in a food questionnaire to obtain individual dietary information relevant to ochratoxin A exposure. The mean plasma level of ochratoxin A was 0.18 ng/ml in Oslo and slightly higher, 0.21 ng/ml (P=0.046) in Visby. There was no correlation between plasma levels of ochratoxin A and the estimated total dietary intake of ochratoxin A based on consumption data and levels in food (retrieved from the literature), neither was the plasma level of ochratoxin A correlated with the total amount of food consumed. However, consumption of several foods, including cereal products, wine, beer and pork, were to some minor degree related to high plasma levels of ochratoxin A. The strongest correlations (correlation coefficient r>0.4; P<0.001) were observed for women in relation to the consumption of beer or medium brown bread. Correlation analysis of combinations of two or more food categories did not result in any statistically significant correlation.

Adult↗

PubMed2001

Tumor vascularization in experimental melanomas: correlation between unenhanced and contrast enhanced power Doppler imaging and histological grading.

The purpose of this study was to evaluate the reliability of unenhanced and enhanced power Doppler sonography in visualization of intratumoral angioneogenesis. Thirty-seven malignant melanomas, which had been implanted intra- or subcutaneously in 22 mice, were examined. Various B-mode criteria, power Doppler criteria and spectral Doppler parameters were evaluated before and after IV-application of the d-galactose-based contrast agent Levovist. After sonographic examination, all tumors were analyzed histologically with semiquantitative grading of tumoral vascularization. Unenhanced, in 70% of the tumors, no intratumoral vessels were visible using power Doppler, but only in 11% of the intracutaneous and in 0% of the subcutaneous after injection of the contrast agent. The enhanced mode was definitely superior to unenhanced Doppler in showing the intratumoral vascularity. The intratumoral vascular structure could be sufficiently analyzed in 30% of all tumors by unenhanced Doppler, but in 92% enhanced. The mean percentage vessel area increased about 433% after application of Levovist (intracutaneous: 485%, subcutaneous: 280%). Despite the missing direct correlation between the sonographically and histologically determined grade of tumor vascularization (Pearson's correlation unenhanced 0,356, p <.05/enhanced 0.395, p <.05), the correlation between the percentage vessel area and the histologic grade of vascularization was improved after application of the contrast agent (Pearson's correlation unenhanced 0.347, p <.05/enhanced 0.686, p <.01). We did not find a significant direct correlation between histologically and sonographically determined degree of vascularization. However, the correlation was improved using a d-galactose-based signal-enhancing agent in power Doppler sonography.

Animals↗

PubMed2000

Correlation model to predict residual immiscible organic contaminants in sandy soils.

Researchers in both environmental and petroleum engineering have conducted studies in one-dimensional columns to quantify the amount of residual nonaqueous phase liquids (NAPL) trapped in the porous media as a function of capillary, viscous and buoyancy forces. From these previous studies, it is proven that significant amounts of the original NAPL spill remain as a trapped residual. The objective of this research was to extend this body of work and to develop a correlation model that could predict residual NAPL saturation as a function of common soil characteristics and fluid properties. These properties include parameters derived from sieve analysis, namely, the uniformity coefficient (C(u)), the coefficient of gradation (C(c)), as well as fluid properties (interfacial tension, viscosity and density). Over 100 column experiments were conducted across a range of nine different soil gradations. The data produced by these tests, along with measured soil and fluid properties, were used to generate correlation models to predict residual NAPL saturation (S(rn)). The first correlation model predicts S(rn) for the region where residual NAPL saturation is independent of the capillary number, and dependent on C(u), C(c) and the Bond number. The second correlation model predicts S(rn) for the region where residual NAPL saturation is dependent on capillary number, as well as C(u), C(c) and the Bond number. The third correlation model predicts S(rn) over the entire region as a function of C(u), C(c) and the total trapping number. The correlation models have a R(2) value of 0.972, 0.934 and 0.825, respectively. Hence, the models may potentially be integrated into site characterization approaches.

Chemical Phenomena↗

PubMed1999

Correlations of plasma growth hormone with somatostatin, gonadal steroid hormones and thyroid hormones in rainbow trout during sexual recrudescence.

The study explores the interrelationships among growth hormone (GH), somatostatin-14 (SRIF), non-esterified fatty acids (NEFA), gonadal steroid hormones and thyroid hormones (THs) in sexually recrudescent rainbow trout (Oncorhynchus mykiss) to examine aspects of the complex set of physiological changes associated with gonadal growth and maturation. Females exhibited significant decreases in plasma SRIF, NEFA and triiodo-L-thyronine (T3) concentrations, and a significant increase in plasma GH concentration associated with gonadal maturation, whereas in males, only SRIF and NEFA concentrations showed significant changes during testicular maturation. The declining SRIF levels during gonadal recrudescence may indicate a role for the hormone in the energy repartitioning processes that occur in both sexes at this time. Correlation analysis of plasma variables revealed a direct correlations between plasma NEFA and 17 beta-estradiol (E2) in females, an inverse correlation between NEFA and testosterone (T) in males, inverse correlations between GH and SRIF in both males and females, and inverse correlations between THs and SRIF concentrations in females. These marked gender differences in correlations likely reflect the different physiological challenges faced by the two sexes and emphasizes the need to consider gender, as well as maturity when studying the interactions of hormones.

Animals↗

PubMed1997

Nullification of a positive correlation between urinary levels of alpha 1-microglobulin and ulinastatin by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in mice.

The relationships between urinary levels of alpha 1-microglobulin (alpha 1M) and ulinastatin (UT) were investigated in C57BL/6J mice, a species which reportedly possesses the gene similar to that of humans for synthesizing the precursor protein of alpha 1M and UT. A positive correlation was established in normal mice. However, repetitive administrations (20 mg/kg, IP, four administrations/12 h) of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) nullified the positive correlation. A similar phenomenon was induced by ICV-administered MPTP (18 and 36 micrograms) in the animals. Furthermore, L-dopa administration (50 mg/kg, IV) in MPTP-treated (1 week after the final IP administration of MPTP) mice reversed the tendency of MPTP, although the agent alone did not affect the positive correlation in normal mice. These results suggest that nullification of the positive correlation probably was induced by the central effects of MPTP. We have found previously that the lack of a positive correlation between urinary levels of alpha 1M and UT distinguishes Parkinson's disease from other neuropsychiatric diseases such as dementia (Alzheimer-type and vascular dementia), schizophrenia and mood disorders. Our present results displayed a phenomenon that the lack of correlation between urinary levels of alpha 1M and UT in patients with Parkinson's disease is reproducible in MPTP-treated mice.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗

PubMed1997

Increasing correlations between personality traits and cortisol stress responses obtained by data aggregation.

Attempts to link personality traits and cortisol stress responses have often been inconclusive. The aim of this paper was to investigate this association by aggregating cortisol stress responses. Therefore, 20 healthy men were exposed to a task consisting of public speaking and mental arithmetics in front of an audience on five days. Six cortisol levels were measured in relation to the stressful task obtained at 10-min intervals on each day. Psychological assessment included the Questionnaire for Competence and Control (FKK) and the Giessen-Test (G-T). These questionnaires focus on assessing personality traits, i.e. locus of control and self-concept. Areas under the response curve (AUC) of the six cortisol samples were computed to obtain an index of the individual's cortisol stress response on each day. Since novelty is a random situational factor likely to mask individual differences in the stress response, the AUC cortisol stress responses of days two to five were consecutively aggregated, excluding the first day. Scales of the two questionnaires employed did not correlate with the AUC cortisol stress response of the first stress trial. The correlation pattern of the AUC cortisol measures of days two to five with the questionnaire scales was inconclusive. However, significant correlations emerged with an increasing number of cortisol stress responses aggregated. Correlations between the measure of social dominance and aggregated AUC cortisol stress responses rose from r = -.47 on day two of the experimental session to r = -.70 after aggregating days two to five. Similarly, measures of locus of control and cortisol stress responses became increasingly correlated with aggregation of several stress exposures. These data provide preliminary evidence for a relationship between questionnaire scales aiming at assessing personality traits and cortisol stress responses uncovered by repeated stress exposure and data aggregation. While novelty may mask the impact of personality on the cortisol stress response on the first exposure, differences in the ability to cope with the stressful situation may lead to different cortisol stress response patterns on subsequent stress exposures. With data aggregation, an association between the trait component of cortisol stress responses and questionnaire scales might be uncovered. For reliable investigation of correlations between personality variables and cortisol stress responses, repeated stress exposure and data aggregation is suggested.

Adult↗

PubMed1979

Morphologic findings in central bronchi correlated to lung function data in obstructive airways disease.

Quantitative analyses of morphologic findings are the condition of clinico-pathological correlation studies. These quantitative analyses are possible by morphometry. The present correlation study shows that morphometry may therefore contribute to understanding the pathogenesis of obstructive airways disease: decreasing bronchial lumen and increasing volume of grandular ducts are correlated to increasing airways resistances (clinical parameters: RAW, FEV1). Increasing volume of bronchial muscles is correlated with resistance of airways at quiet breathing (RAW) and less with increasing residual volume (RV). Increasing volume of bronchial glands and glandular ducts is correlated with increasing resistance at forced expiration which is clinically shown by decreasing FEV1. These findings can be interpreted as follows. Airway resistances are mainly influenced by airway narrowing. At quiet breathing, muscle constriction is an additional cause of increasing airflow resistance due to bronchial narrowing. At forced expiration, however, mucus plugs probably limit the airflow because thickening of bronchial glands points to increased secretory activity. Until now it is not possible to understand why bronchial muscle volume correlates with residual volume.

Adult↗

PubMed2000

Quantification of intracavitary brachytherapy parameters and correlation with outcome in patients with carcinoma of the cervix.

PURPOSE: To quantify the M. D. Anderson criteria for acceptable implant geometry; to relate our system of intracavitary radiotherapy (ICRT) prescription to Manchester and ICRU reference doses; and to correlate these parameters with outcome measures. METHODS AND MATERIALS: The relationships between intracavitary applicators and normal structures were measured directly from localization films of 808 applications performed in 396 patients who completed definitive treatment for cervical cancer between 1990 and 1994. The distances between applicators and tissue landmarks and the doses to Manchester and normal tissue reference points were correlated with outcome. RESULTS: The median distance from the tandem to the sacrum was 4.0 cm, or one-third the distance from the pubis to the sacrum. The mean distance between the vaginal ovoids and cervical marker seeds was 7 mm, and the median distance between the tandem and the posterior edge of the ovoids was 50% of the ovoid length. In 92% of insertions, vaginal packing was posterior to or within 5 mm of a line that passed through the posterior edge of the ovoids, parallel to the tandem. The median doses to Point A and rectal, bladder, and vaginal surface reference points were 87 Gy, 68 Gy, 70 Gy, and 125 Gy, respectively. Although these reference doses were not routinely used to prescribe treatment, consistent applicator geometry and source selection resulted in a relatively narrow range of delivered doses. The average ratios between the doses at bladder or rectal reference points and Point A were somewhat greater when smaller vaginal applicators were used. Patients received a median of 5600 mgRaEq-h from ICRT. The total mgRaEq-h were correlated with but were not proportional to the dose at Point A. There were no significant correlations between the doses to standard reference points and the rates of central recurrence or major complications. CONCLUSION: When ICRT implants are carefully placed, relatively high paracentral doses can be delivered that yield a high rate of central disease control with an acceptable rate of complications. The narrow range of doses delivered to standard reference points and their inconsistent correlation with the maximum doses delivered to normal tissues probably contributed to a lack of correlation between reference doses and outcome.

Adult↗

PubMed1997

A correlation between residual DNA double-strand breaks and clonogenic measurements of radiosensitivity in fibroblasts from preradiotherapy cervix cancer patients.

PURPOSE: To study the relationship between residual DNA damage and clonogenic measurements of radiosensitivity in fibroblasts from pretreatment cervix cancer patients. METHODS AND MATERIALS: Early passage vaginal fibroblasts from nine preradiotherapy cervix cancer patients and two radiosensitive skin fibroblast cell strains were studied. Cell survival was measured by clonogenic assay following both high and low dose rate irradiation. Residual DNA damage was measured using pulsed-field gel electrophoresis (PFGE) after irradiating radiolabeled, plateau-phase cells at 37 degrees C and allowing 24 h for repair. DNA damage was expressed both in terms of the residual damage slope (fitted to data from 60 to 150 Gy) and the fraction of activity released (FAR) following 150 Gy. RESULTS: The surviving fraction at 2 Gy (SF2) values after high dose rate irradiation for the vaginal fibroblasts ranged from 0.15 to 0.32 (a 2.2-fold difference). When the two radiosensitive cell strains were included, residual damage, expressed as the residual damage slope, correlated with alpha (r = 0.82, p = 0.002), D bar (r = -0.91, p < 0.001) and SF2 (p = -0.79, p = 0.004), and when the vaginal fibroblasts alone were studied, the residual damage slope again correlated with clonogenic survival, although less strongly [alpha (r = 0.66, p = 0.053), D bar (r = -0.83, p = 0.006), and SF2 (r = -0.63, p = 0.07)]. Within the group of vaginal fibroblasts there was a 4.0-fold difference in residual DNA damage slope. When residual damage was expressed as FAR at 150 Gy, then for all cell strains the correlations were alpha: r = 0.78, p = 0.004, D bar: r = -0.86, p = 0.001, and SF2: r = -0.78, p = 0.004, and for the vaginal fibroblast strains alone the correlations were alpha: r = 0.60, p = 0.088, D bar: r = -0.75, p = 0.02, and SF2: r = 0.62, p = 0.077. CONCLUSION: This study confirms previous findings that residual DNA damage correlates with clonogenic survival in fibroblasts. In addition, it demonstrates a correlation for fibroblasts from pretreatment cervix cancer patients demonstrating a relatively small range of SF2 values.

Cell Survival↗

PubMed1999

The correlation of protein hydropathy with the base composition of coding sequences.

The "universal correlation" (D'Onofrio, G., Bernardi, G., 1992. A universal compositional correlation among codon positions. Gene 110, 81-88.) that holds between and or ( values are the average values of the coding sequences of each genome analyzed) at both the inter- and intra-genomic level, was re-analyzed on a vastly larger dataset. The results showed a slight, but significant, difference in the vs. correlations exhibited by prokaryotes and eukaryotes. This finding prompted an analysis of the correlation between and the amino acid frequencies in the encoded proteins, which has shown that positive correlations exist between values of coding sequences and the hydropathy of the corresponding proteins. These correlations are due to the fact that hydrophobic and amphypathic amino acids increase, whereas hydrophilic amino acids decrease with increasing values. Hydropathy values of prokaryotic proteins are systematically higher than those of eukaryotes, but the slopes of the regression lines are identical. The lower hydrophobicity of eukaryotic proteins is due to differences in the amino acid composition. In particular, the twofold higher cysteine (and disulfide bond) level of eukaryotic proteins compared to prokaryotic proteins most probably compensates for their lower hydrophobicity. This supports the viewpoint that hydrophobicity plays a structural and functional role as far as protein stability is concerned.

Amino Acids↗

PubMedDate not supplied

Low-frequency velocity correlation spectrum of fluid in a porous media by modulated gradient spin echo.

In addition to the fast correlation for local stochastic motion, the molecular velocity correlation function in a fluid enclosed within the pore boundaries features a slow long time-tail decay. Here we present its study by the NMR modulated gradient spin-echo method (MGSE) [1] on a system of water trapped in the space between the closely packed polystyrene beads. With MGSE pulse sequence, a repetitive train of RF pulses with interspersed gradient pulses periodically modulates the spin phase. It gives the spin echo attenuation proportional to a value of the molecular velocity correlation spectrum at the modulation frequency. Covering the frequency range between Hz and MHz, it is a complement to the quasi-elastic neutron scattering, and so a suitable technique for the investigation of low frequency molecular dynamics in fluids. In our experiment, it enables to extract the low frequency correlation spectrum of water molecules confined in porous media. The function exhibits a negative long time-tail characteristic (a low frequency decay of the spectrum), which can be interpreted as a molecular back scattering on boundaries. The results can be well fitted with the spectrum calculated from the solution of the Langevin equation for restricted diffusion (which exhibits an exponential decay) [2] as well as with the spectrum obtained when simulating the hydrodynamics of molecular motion constrained by capillary walls (which gives an algebraic decay) [3]. Despite much work on theories and simulation, which predict slow negative long time tail of molecular velocity correlation dynamics in confined fluids, the obtained velocity correlation spectrum is the first experimental evidence to confirm these effects. The obtained dependence of spin echo attenuation on time, gradient strength and modulation frequency is also the first experimental verification of the recently developed approach to the spin echo in porous media, that uses the spin phase average with the cumulant expansion to get the attenuation as a discord of spin spatial coherence [4].

Magnetic Resonance Spectroscopy↗

PubMed1999

Correlation between enhancing lesion number and volume on standard and triple dose gadolinium-enhanced brain MRI scans from patients with multiple sclerosis.

We investigated the correlations between numbers and volumes of multiple sclerosis (MS) lesions enhancing on standard dose (SD) and triple dose (TD) gadolinium (Gd)-enhanced brain magnetic resonance imaging (MRI) scans, to clarify whether the measurement of enhancing lesion volumes or the use of TD MRI give additional information which can not be obtained by counting enhancing lesions on SD scans. SD and TD Gd-enhanced brain MRI scans were obtained every month for three months from 40 MS patients. The numbers of total and new enhancing lesions were counted, and the total volumes of enhancing lesions were measured from each of the four scans obtained with the two techniques. Univariate correlations between enhancing lesion numbers and volumes were assessed. The numbers of total and new enhancing lesions seen either on SD or TD scans were significantly correlated (r = 0.91 and 0.93, respectively). The numbers and volumes of total enhancing lesions were significantly correlated on both SD (r = 0.90), and TD (r = 0.89) scans. Moderate correlations were found between the total number of enhancing lesions on SD scans and the average difference between TD and SD scans for total enhancing lesion number (r = 0.66), and between the number of new enhancing lesions on SD scans and the average difference between TD and SD scans for new enhancing lesion number (r = 0.50). Our findings indicate that, both on SD and TD MRI, the counts and the volumes of total and new enhancing lesions are highly correlated, and that lesion counting may suffice to monitor MS activity. On the contrary, this study confirms the usefulness of TD MRI for a more complete assessment of the acute changes occurring in MS patients.

Brain↗

PubMed2003

Test-retest reliability of a questionnaire on physical activity and its correlates among women from diverse racial and ethnic groups.

BACKGROUND: A better understanding of physical activity and its correlates is needed, especially among diverse populations of women. The objective of this study was to examine the test-retest reliability of a survey designed to measure physical activity and its correlates among women from diverse racial and ethnic groups. METHODS: Test and retest surveys were conducted in person or over the telephone with 344 white, Latina, African-American, and Native American women aged 20 to 50 years living in rural and urban areas of the United States. Reliability of self-reported physical activity and its correlates were determined using intraclass correlation coefficients (ICC) overall and separately by site and race/ethnicity. RESULTS: Of the women responding, 45% of the participants met recommendations for physical activity, 40% were insufficiently active, and 15% were inactive. Reliability for the physical activity measure was 0.69 (95% confidence interval [CI], 0.62-0.74), with an ICC of 0.30 to 0.95 across sites. Overall, the seven items on the physical environment had substantial reliability (ICC=0.64-0.91). The sense of community scale (0.79; 95% CI, 0.74-0.83), social issues (0.68; 95% CI, 0.61-0.74), social roles (0.64; 95% CI, 0.56-0.71), and self-efficacy for exercise (0.72; 95% CI, 0.66-0.77) all had acceptable reliability overall and across most sites. CONCLUSIONS: This study provides psychometric evidence that the questionnaire on physical activity and its correlates is reliable among diverse women aged 20 to 50 years from various racial and ethnic groups. These results suggest that test-retest reliability is not an obstacle to comparison of associations between physical activity and several hypothesized correlates of activity.

Adult↗

PubMed1996

Correlation of measured range of hip motion following total hip arthroplasty and responses to a questionnaire.

Twenty-eight patients (with 30 primary and 8 revision total hip arthroplasties) completed a standardized questionnaire containing the Western Ontario and McMaster Universities (WOMAC) osteoarthritis index and Harris hip score questions prior to an office visit a minimum of 1 year after surgery. The range of hip motion measured by an orthopaedic surgeon was compared with the responses to questions on stiffness and function as well as with global scores in the WOMAC osteoarthritis index. Patient responses to the questions asking if they could cut their toenails on the operated side and the Harris hip score question asking if they could put on socks and tie a shoe correlated significantly with postoperative hip motion (P < .005). The WOMAC global pain and stiffness scores did not correlate with range of motion. The WOMAC physical function score correlated significantly only with hip flexion (P < .05). Of the WOMAC physical function questions, difficulty bending to pick an object off the floor (P < .05) and getting on and off the toilet (P < .05) correlated with the sum of the range of motion in all planes and weighted Harris hip score range of motion calculation. These data suggest that the points allocated in the Harris hip score for range of motion can be estimated reasonably accurately from questionnaire or phone response to a series of questions on a standardized questionnaire. The question on ability to cut toenails or the Harris hip score question regarding ability to put on socks and tie a shoe correlated with the most individual planes of motion, but several WOMAC physical function questions also correlated with total and weighted range of motion calculations.

Activities of Daily Living↗

PubMed2000

Nonlinear canonical correlation analysis by neural networks.

Canonical correlation analysis (CCA) is widely used to extract the correlated patterns between two sets of variables. A nonlinear canonical correlation analysis (NLCCA) method is formulated here using three feedforward neural networks. The first network has a double-barreled architecture, and an unconventional cost function, which maximizes the correlation between the two output neurons (the canonical variates). The remaining two networks map from the canonical variates back to the original two sets of variables. Tested on data sets with correlated nonlinear structures, NLCCA showed that the underlying nonlinear structures could be retrieved accurately under moderately noisy conditions. After a mode had been retrieved, NLCCA was applied to the residual to successfully retrieve the next mode. When tested for prediction skills, the NLCCA outperformed the CCA when the two sets of variables contained correlated nonlinear structures.

Artifacts↗

PubMed2002

Correlation between diastolic impairment and lipid metabolism in mild-to-moderate hypertensive postmenopausal women.

BACKGROUND: Many cardiovascular risk factors are found in hypertensive patients. The aim of this study was to evaluate the correlation between cardiac abnormalities (ie, diastolic and left ventricular hypertrophy) with other cardiovascular risk factors in postmenopausal women with hypertension. METHODS: A total of 200 consecutive postmenopausal women (mean age 47.5+/-4 years) with mild-to-moderate hypertension that had never been treated were studied. Mean systolic pressure was 163+/-15 mm Hg and mean diastolic pressure 97+/-75 mm Hg. All subjects underwent M-mode two-dimensional echocardiography and cardiac Doppler. The following measurements were made: peak velocity of early left ventricular filling (E); peak velocity of late ventricular filling (A), and the ratio between early and late flow velocity peaks (E/A). The E/A ratio was then normalized for heart rate (E/Ac). Left ventricular mass index normalized for body surface was also measured. In each patient, total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and plasma triglycerides were measured. We evaluated the correlation of E/Ac and left ventricular mass index (LVMI) with the following variables: total cholesterol, HDL, LDL, triglyceridemia, smoking status, systolic and diastolic blood pressure, and body mass index. RESULTS: A significant negative correlation with total cholesterol (r = -0.15, P < .05) and LDL (r = -0.20; P = .005), as well as a significant positive correlation with HDL (r = 0.20, P < .01) were found. No other variable was significantly correlated with E/A. There was no correlation between LVMI and any variable analyzed. CONCLUSION: In postmenopausal women with mild-to-moderate hypertension, high total cholesterol levels and low HDL levels are associated with impaired diastolic function.

Adult↗