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PubMed2001

Predictors of social relations in persons with schizophrenia living in the community: a Nordic multicentre study.

BACKGROUND: Deinstitutionalisation has led to persons with serious mental illness spending most of their time outside psychiatric institutions. Not much is known about their social life. The paper presents the results of structured interviews with non-institutionalised persons with schizophrenia about treatment, care and social network. The network data are analysed from three perspectives: finding predictors of the number and of the quality of social contacts, and establishing the respective variables that characterise persons with high, and those with low, scores on both the quantity and quality dimensions of social integration. METHODS: Random samples of persons with schizophrenia receiving outpatient services in ten psychiatric centres in the four Nordic countries were interviewed. The following instruments were used: Interview Schedule for Social Interaction (ISSI), Camberwell Assessment of Needs, Lancashire Quality of Life Profile, General Assessment of Functioning (GAF) and Brief Psychiatric Rating Scale (BPRS), in addition to a checklist covering the utilisation of different services. The ISSI provided the main data for this paper. A restricted number of possible predictors were used in General Linear Model (GLM) factorial analysis and discriminant analysis. RESULTS: A total of 418 persons took part in the study. The overall participation rate was 55%. Social integration in terms of number of contacts was related to a high GAF score, few BPRS negative and hostility symptoms, having contact with user organisations and living in urban (in contrast to rural) areas. Availability of emotional relations was predicted by female sex, low scores on the BPRS hostility dimension, high GAF score, having contact with one's family more than once a month, and living in urban areas. Work, adequate leisure activities and GAF score discriminated between the best and worst integrated groups. CONCLUSIONS: Living in urban areas, being female, having a high GAF score and low scores on hostility predicted better integration in terms of number of contacts and emotional relations.

Adult↗

PubMed1989

[Multivariate statistical analysis in stabilometry in human upright standing (second report)--pattern recognition of a stabilogram].

A pattern of a figure which is displayed by an X-Y recorder or by a polygraph in stabilometry may present several qualitative facts about the standing ability of a test-subject. The purpose of this study was to make a quantitative evaluation of the body stability in both normal and ataxic patients who were standing erect. The technique utilised was pattern-recognition, composed of principal component analysis and discriminant analysis. Stabilometrical examinations were carried out in 20 normal subjects, 39 with peripheral vestibular disturbance and 11 with disturbance of the central origin. Each examinee was ordered to keep an upright posture for 60 seconds both with the eyes open and with the eyes closed. The following parameters were used: the area of the ellipse for rejection by a statokinesigram, the maximum width and the total length of body excursion, the root mean square, the velocity, the acceleration and the average frequency in the horizontal plane. These were the same parameters that were used in the first report. Each component predicting a specific character in stabilometry was identified by this study of principal component analysis. The relationship between the components in order and its prediction were as follows: the first component predicted the size of the body movement, the second the force, the third the density, the fourth the difference between body movement with the eyes open and with the eyes closed and the fifth the direction of body sway. Furthermore, the principal components were successfully utilized to allow the classification of the test subjects into three groups: those who were normal, those with peripheral vestibular disturbance and those with disturbance of the central origin. Discriminant functions were also used to classify the above mentioned three groups and another five groups, namely: those who were normal, those with vestibular neuronitis, those with positional vertigo of the benign paroxysmal type, those with Ménière's disease and those with cerebellar ataxia. In classification of the three groups, the significant parameters used for discrimination were as follows (P less than 0.05): the root mean square with the eyes open, the distance and the maximum width of body excursion in the Y direction with the eyes open, the area of the ellipse for rejection both with the eyes open and with the eyes closed, the maximum width and the average frequency in the X direction with the eyes closed.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

PubMed1980

Use of the multivariate approach to enhance the diagnostic accuracy of the treadmill stress test.

Twenty-one variables were analyzed in 142 male and 57 female individuals selected in a nonconsecutive fashion from a computerized list of patients with an angiogram and treadmill stress test. Patients were categorized as "normal" or "diseased" on the basis of angiographic results, significant coronary artery disease being defined as 70 percent or greater stenosis of one or more coronary arteries. Ten of the variables in males, and 14 of the 21 variables in females exhibited statistically significant differences between normal and diseased groups in univariate analysis of variance. Multivariate discriminant analysis, however, showed only three variable (duration, infarct by ECG, and ST depression in the immediate recovery period) to be significant in the final ranking for males; while five variables (infarct by history, presence of anginal pain during the test, ST resting changes in the normal individual, infarct by ECG, and age) were significant discriminators in females. For males, the sensitivity was 84%, the specificity was 80%, and the predictive value was 89%. For females, these values were 85%, 94% and 90%, respectively; while the entire group they were 85%, 86%, and 89%. In the classification matrices, males showed a misclassification percentage of 17% while females showed a 9% misclassification rate. Most of the misclassifications occurred with posterior probabilities ranging from 0.5 (50%) to 0.7 (70%); very few patients with high posterior probabilities were misclassified. It is concluded that multivariate discriminant analysis is a reliable means of determining the probability of coronary artery disease in a highly select group of patients; i.e. a large enough number of patients could be correctly classified with a high degree of certainty.

Adult↗

PubMed1996

Outbreak of multi-drug resistant Staphylococcus aureus: a cluster analysis.

BACKGROUND: Outbreaks of multi-drug resistant Staphylococcus aureus over eight years were investigated to prevent future endemic. METHODS: Isolates of multiresistant S. aureus underwent a cluster analysis combined with canonical discriminant analysis using bacteriologic biotyping and sensitivity to 21 drugs. RESULTS: Of a total of 786 strains recovered from 155 in-patients, the specialty surgical ward (SW) exhibited 470 isolates (59.8%) and the general SW 214 (27.2%). Among six clusters formed, four clusters were predominant in the general SW. An ordination diagram from the canonical discriminant analysis revealed a distribution in which clusters were localized temporally (year) and spatially (ward). A yearly shift of clusters indicated emergence of a new phenotype of multiresistant S. aureus. CONCLUSIONS: The cluster analysis of isolates of multiresistant S. aureus using biotyping and sensitivity may supplement the classical method of tracing the spreading patterns of this microbe.

Anti-Bacterial Agents↗

PubMed2003

Micro-Raman spectroscopy of natural and synthetic indigo samples.

In this work indigo samples from three different sources are studied by using Raman spectroscopy: the synthetic pigment and pigments from the woad (Isatis tinctoria) and the indigo plant (Indigofera tinctoria). 21 samples were obtained from 8 suppliers; for each sample 5 Raman spectra were recorded and used for further chemometrical analysis. Principal components analysis (PCA) was performed as data reduction method before applying hierarchical cluster analysis. Linear discriminant analysis (LDA) was implemented as a non-hierarchical supervised pattern recognition method to build a classification model. In order to avoid broad-shaped interferences from the fluorescence background, the influence of 1st and 2nd derivatives on the classification was studied by using cross-validation. Although chemically identical, it is shown that Raman spectroscopy in combination with suitable chemometric methods has the potential to discriminate between synthetic and natural indigo samples.

Journal Article↗

PubMed1995

Sex determination from the pubis by discriminant function analysis.

A total of 122 adult human pubes (66 males and 56 females) are used in this study of a discriminant function analysis for determining sex from four pubic measurements: the angle formed by the middle line of the superior ramus and inferior ramus of pubis (in degrees, X1), subpubic angle (in degrees, X2), the minimum distance from the symphyseal surface to the obturator (in millimeters, X3), and the minimum thickness of the ischiopubic ramus (in millimeters, X4). The method introduced by Fisher is used. Using the formula Y = 0.270 mean1-0.985mean2-0.761mean3 + 1.806mean4,F = 200 F = 200 (F > F0.01(4,117), P < 0.01), section point -32.47, an accuracy of 100% could be achieved for 230 pubes (130 males, 100 females).

Discriminant Analysis↗

PubMed1985

A longitudinal study of the reporting of emotional and somatic symptoms during and after pregnancy.

One hundred and eight pregnant women, most of their husbands and a comparison group of non-expectant parents were recruited for a long-term study which involved responding to a 55-item Symptom Checklist (SCL) and the Beck Depression Inventory three times during pregnancy and once during the first postpartum month. Responses to the SCL were factor analysed, and the four groups were then compared on their factor scores as well as their scores on the Beck Depression Inventory (BDI) using discriminant analysis and trend analysis. The discriminant analyses were done twice: once using all the data provided by all subjects and once using only subjects with no missing data. At each measurement period, the pregnant women were distinguished from the other groups by a different factor of the SCL: at 3-5 months, it was 'Feeling Sick'; at 6-8 months, it was 'Feeling Overweight'; at 9 months, it was 'Feeling Overweight/Physical Stress'; and at postpartum, it was 'Physical Stress'. Also, trend analysis showed a significant tendency for the scores of pregnant women on the SCL 'Negative Emotional State', factor and on the BDI to increase over time, in contrast to those of the other groups.

Adaptation, Psychological↗

PubMed1999

Morphological variation in great ape and modern human mandibles.

Adult mandibles of 317 modern humans and 91 great apes were selected that showed no pathology. Adult mandibles of Pan troglodytes troglodytes, Pongo pygmaeus pygmaeus and Gorilla gorilla gorilla and from 2 modern human populations (Zulu and Europeans from Spitalfields) were reliably sexed. Thirteen measurements were defined and included mandibular height, length and breadth in representative positions. Univariate statistical techniques and multivariate (principal component analysis and discriminant analysis) statistical techniques were used to investigate interspecific variability and sexual dimorphism in human and great ape mandibles, and intraspecific variability among the modern human mandibles. Analysis of interspecific differences revealed some pairs of variables with a tight linear relationship and others where Homo and the great apes pulled apart from one another due to shape differences. Homo and Pan are least sexually dimorphic in the mandible, Pan less so than Homo sapiens, but both the magnitude of sexual dimorphism and the distribution of sexually dimorphic measurements varied both among and between modern humans and great apes. Intraspecific variation among the 10 populations of modern humans was less than that generally reported in studies of crania (74.3% of mandibles were correctly classified into 1 of 10 populations using discriminant functions based on 13 variables as compared with 93% of crania from 17 populations based on 70 variables in one extensive study of crania). A subrecent European population (Poundbury) emerged as more different from a recent European population (Spitalfields) than other more diverse modern populations were from each other, suggesting considerable morphological plasticity in the mandible through time. This study forms a sound basis on which to explore mandibular variation in Neanderthals, early Homo sapiens and other more ancient fossil hominids.

Adult↗

PubMed1998

Effect of altered sensory conditions on multivariate descriptors of human postural sway.

Multivariate descriptors of sway were used to test whether altered sensory conditions result not only in changes in amount of sway but also in postural coordination. Eigenvalues and directions of eigenvectors of the covariance of shnk and hip angles were used as a set of multivariate descriptors. These quantities were measured in 14 healthy adult subjects performing the Sensory Organization test, which disrupts visual and somatosensory information used for spatial orientation. Multivariate analysis of variance and discriminant analysis showed that resulting sway changes were at least bivariate in character, with visual and somatosensory conditions producing distinct changes in postural coordination. The most significant changes were found when somatosensory information was disrupted by sway-referencing of the support surface (P = 3.2 x 10(-10)). The resulting covariance measurements showed that subjects not only swayed more but also used increased hip motion analogous to the hip strategy. Disruption of vision, by either closing the eyes or sway-referencing the visual surround, also resulted in altered sway (P = 1.7 x 10(-10)), with proportionately more motion of the center of mass than with platform sway-referencing. As shown by discriminant analysis, an optimal univariate measure could explain at most 90% of the behavior due to altered sensory conditions. The remaining 10%, while smaller, are highly significant changes in posture control that depend on sensory conditions. The results imply that normal postural coordination of the trunk and legs requires both somatosensory and visual information and that each sensory modality makes a unique contribution to posture control. Descending postural commands are multivariate in nature, and the motion at each joint is affected uniquely by input from multiple sensors.

Adult↗

PubMed1992

Age-specific correlation analysis of longitudinal physical fitness levels in men.

This study investigated the age-specific tracking of adult health- and performance-related fitness scores. In addition, the independent contribution of adolescent physical characteristics to the explanation of adult fitness scores was also studied. The sample consisted of 173 adults observed at age 30 years. These subjects had been followed at annual intervals from age 13 to age 18 years and were remeasured at age 30 years. At each age nine fitness tests were administered together with the recording of anthropometric dimensions, biological maturation, sports participation and family characteristics. Tracking was measured by the inter-age correlations at each age between 13 and 18 years and the performance scores at 30 years. The independent contribution of characteristics observed during adolescence to the explanation of adult fitness was investigated through stepwise multiple regression analysis and discriminant analysis with the adult fitness scores as the dependent variables and the fitness, maturation, anthropometric characteristics, sports participation and family background as the independent variables. Tracking between age 13 and age 30 years was moderately high (46% of variance explained) for flexibility, low to moderate (between 19% and 27% of variance explained) for the other fitness parameters and low for pulse recovery and static strength (7% to 11% of variance explained). Between age 18 and age 30 years the tracking was high for flexibility, moderately high for explosive and static strength, and moderate for the other fitness parameters except for pulse recovery. The amount of variance of adult fitness levels explained increased significantly when other characteristics observed during adolescence entered the regressions or discriminant functions.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1994

Peripheral blood CD5+ B cell subset in the remission phase of systemic connective tissue diseases.

OBJECTIVE: To get a better insight into the level of circulating CD5+ B cells as related to the systemic connective tissue disease activity. METHODS: Peripheral blood CD5+CD19+ cells of patients in the remission phase of systemic lupus erythematosus (SLE) (n = 28), Sjögren's syndrome (SS) (n = 20), rheumatoid arthritis (RA) (n = 26), and 19 control healthy subjects were analyzed by 2-color flow cytometry. RESULTS: In comparison to control group, the patients with SLE had a significant increase in the relative CD19+CD5+ blood cell count (p < 0.0005); this count was also different from the finding in both RA (p < 0.005) and patients with SS (p < 0.05). In contrast, the proportion of B cells expressing CD5 (within an individual B cell population) was significantly increased in all the 3 diseases compared to healthy subjects (SLE, p < 0.0001; SS, p < 0.05; and RA, p < 0.01). In the multivariate discriminant analysis, a discriminant function defined by the CD19+CD5+ subset strongly discriminated SLE, SS and RA from the control, but also SLE from both SS and RA. CONCLUSION: Our findings demonstrated that, in relation to healthy control subjects, the blood CD5+ B subset tended to be elevated in the patients in the remission phase of systemic connective tissue diseases, particularly in SLE.

Adult↗

PubMed2000

Determination of cow's milk and ripening time in nonbovine cheese by capillary electrophoresis of the ethanol-water protein fraction.

A novel method is reported for analyzing adulteration of goat and ewe cheeses with cow's milk: capillary zone electrophoresis (CZE) in isoelectric, acidic buffers (50 mM imino diacetic acid, IDA, pH = pI 2.3). The cheese samples were extracted with a 20:80 v/v ethanol-water mixture in presence of 3 M urea and 1% beta-mercaptoethanol for 1 h. After centrifugation and lipid extraction, the samples were dissolved in 50 mM IDA, 6 M urea and 0.5% hydroxyethyl cellulose and analyzed by CZE at 700 V/cm. A total of 18 characteristic peaks were resolved among the three types of cheeses and 18 variables were defined as their respective areas. There was excellent similarity among the electrophoretic patterns obtained with cheeses of a given type of milk, while cheeses made with different types of milk were easily distinguishable. Most peaks were common to all cheeses, but the profile differed depending on the type of milk used. Principal component analysis, linear discriminant analysis, and partial least squares regression (PLS) were used for statistical analysis of the data obtained by CZE. In particular, by using PLS multivariate regression, the contents of cow's milk in presumably pure goat and ewe cheeses, as well as in binary and ternary mixtures, could be predicted with relative standard deviations of ca. 6-7%. In addition, the ripening time in goat and ewe cheeses could also be predicted.

Animals↗

PubMed1991

Depression and personality disorder: differential diagnosis with the MMPI.

This study assessed the effectiveness of the MMPI in differentiating four clinically relevant types of depression. MMPI profiles of 53 subjects with major depression and personality disorder, 44 subjects with other depression and personality disorder, 27 subjects with major depression without personality disorder, and 20 subjects with other depression without personality disorder were compared via MANOVA, high-point pair analysis, and discriminant analysis. The instrument was found somewhat effective in differentiating the groups at a statistically significant level, but the differences were too subtle to be considered clinically useful. Thus, while the MMPI has some usefulness in the differential diagnosis of depression, it is best used in conjunction with other test data and relevant historical data.

Adjustment Disorders↗

PubMedDate not supplied

Dynamic 3D-MR mammography: is there a benefit of sophisticated evaluation of enhancement curves for clinical routine?

The purpose of the study was to compare standard analysis with pharmacokinetic analysis of time-intensity curves in dynamic three-dimensional (3D) MR mammography (MRM) for their capability of differentiating benign from malignant disease. Dynamic MRM of the whole breast was performed at 1.0 T using an axial fast low-angle shot (FLASH) 3D sequence. For the standard evaluation, the enhancement of the first minute (E1) and the slope of enhancement from minute 2 to 10 (SE2-10) were calculated. For pharmacokinetic analysis, the amplitude of enhancement (A), distribution time (t21), and elimination time (tel) were computed. Sixty-two histologically verified lesions were evaluated. The standard evaluation methods yielded a highly significant difference between benign and malignant disease for E1 (P = .0008) and SE2-10 (P = .0001). The pharmacokinetic parameters gained similarly significant P values (A, P = .0014; t21, P = .0024; tel, P = .0001). Both standard and pharmacokinetic analysis concordantly discriminated between benign and malignant lesions in discriminant analysis. Compared with standard analysis, a pharmacokinetic analysis of time-intensity curves is not beneficial for routine clinical diagnosis.

Adolescent↗

PubMed2005

Metabolic characterization of distinct neuroanatomical regions in rats by magic angle spinning 1H nuclear magnetic resonance spectroscopy.

High-resolution magic angle spinning (HRMAS) (1)H NMR spectroscopy has been applied to the biochemical characterization of specific brain regions in rats in order to establish baseline levels of tissue metabolite profiles with which to compare models of neuropathology or toxic lesion. Cores of tissue (20 mg) from the brain stem, cerebellum, frontal cortex, and hippocampus were obtained from histologically defined coronal slices of brain from 18 male Sprague-Dawley rats. HRMAS (1)H NMR spectra were acquired for each of the regions sampled and the degree of intersample variability, as assessed by principal components analysis and discriminant analysis by projection to latent structure was found to be low. Clear region-specific differences in the biochemical profiles were observed using both comparison of metabolite ratios and/or pattern recognition methods. Relatively low concentrations of GABA in the cerebellum, high concentrations of taurine and N-acetylaspartate in the cortex, and high levels of choline, glycerophosphocholine, and phosphocholine in the hippocampus predominantly influenced the classification of the different brain regions. Additionally, N-acetylaspartylglutamate was detected in the brain stem, but was largely absent from the other regions examined. Such analyses provide a baseline reference for further HRMAS NMR spectroscopic studies to monitor disease and pharmacological insults in specific regions of the brain.

Animals↗

PubMed2003

Pseudomonas aeruginosa and cystic fibrosis: correlation between exoenzyme production and patient's clinical state.

In this study, we investigated the correlation between the production by Pseudomonas aeruginosa isolates of four exoenzymes (protease, elastase, neuraminidase, and phospholipase C (PLC)) and the clinical state of cystic fibrosis (CF) patients. We studied 212 P. aeruginosa isolates from 22 CF patients chronically infected with this bacterium. Patients were classified into three clinical groups according to a modified Shwachman-Kulczycki-Khaw (SKK) scoring system. The production of enzymes by isolates from patients in the three populations was analyzed and compared using four statistical tests: chi-square, Mann-Whitney U, principal component analysis, and discriminant analysis. Isolates from patients with excellent or good clinical status (group I, SKK score >/=71) had higher elastase and neuraminidase activities than isolates from the other patients. In contrast, PLC activity, a common characteristic of CF isolates, was higher in isolates from patients with poor or weak clinical status (group III, SKK score </=55). PLC also appeared to be the best parameter for differentiating between groups I and III. Enzyme production was highly variable in group II isolates (SKK score, 56-70). Our results suggest that P. aeruginosa isolates from patients with good clinical status produce large amounts of neuraminidase, and that PLC production may be involved in the decrease in pulmonary function.

Child↗

PubMed2001

Dependence of 13C NMR chemical shifts on conformations of rna nucleosides and nucleotides.

Cross-polarization magic-angle spinning solid-state NMR spectroscopy has been used to investigate the dependence of (13)C sugar chemical shifts on specific conformational parameters of a variety of ribonucleotides and ribonucleosides. Solid-state NMR is a valuable tool for nucleoside and nucleotide structural studies since it provides the means to acquire spectra that correspond to single conformations, as opposed to (13)C solution NMR methods. The distinct effects of sugar puckering on the C1', C4', and C5' resonances of C2' endo (S type) and C3' endo (N type) furanoid conformations allow us to separate them into two groups. Further analysis of each group reveals an additional dependence of the C1' and C5' resonances on the glycosidic and C4'-C5' exocyclic torsion angles, respectively. However, it is found that the glycosidic conformation cannot independently be determined from sugar (13)C chemical shift data. The statistical methods of exploratory data analysis and discriminant analysis are used to construct two canonical coordinates-linear combinations of chemical shifts which give the statistically optimal determination of the conformation from the NMR data.

Carbohydrate Conformation↗

PubMed1998

Differentiation of soy sauce types by HPLC profile pattern recognition. Isolation of novel isoflavones.

Nonvolatile minor components in various brands of Japanese fermented soy sauce were analyzed by gradient RP-HPLC and monitored at 280 nm. Chemometric pattern recognition techniques, such as cluster analysis, linear discriminant analysis (LDA), LDA using genetic algorithm (GA-LDA) and soft independent modelling of class analogy (SIMCA), succeeded in differentiating the resulting HPLC profiles according to soy sauce brands. Three components playing key roles in the differentiation were isolated by preparative HPLC and purified by gel-filtration chromatography, or simply repeated preparative HPLC. FAB-MS, 1H-, 13C-NMR and IR spectra suggested that these three components having molecular weights of 386, 402 and 418 were isoflavone derivatives. By applying HMBC spectral analysis, these isoflavones were identified as conjugated ethers of tartaric acid with daidzein, genistein and 8-hydroxygenistein. These new isoflavone derivatives are produced by some strains of Aspergillus fungi.

Chromatography, High Pressure Liquid↗