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[Distribution pattern, statistical analysis and correlation of selenium levels in swine selenium-indicating organs].

There is a potential risk of excessive selenium levels in organs of swine, resulting in toxicity and residues in pork, or selenium deficit. Therefore, random selenium mean values in "selenium-indicating" organs of pigs selected from suspicious populations were compared with mean and limiting values (reference or normal values) recorded from animals with intact metabolism. Prerequisites required for such comparative assessment included the availability of estimated variance values and knowledge of the presence of abscence of agreement between normal distribution and empirical frequency distribution for the population concerned. Knowledge must be available also on the informative value of measured selenium data in blood plasma and their relevance to the general selenium situation in the organism and muscle at large. These were some of the problems studied by determining selenium levels in the liver, kidneys, blood plasma, and M. longissimus dorsi. Organic selenium concentrations were found to be distributed with right axis deviation but almost normal. The parameters established were typical of the majority of data known from literature. Those date, however, are quite variable, so that the need for independently prepared reference values cannot be abandoned. Correlation analysis showed reciprocal relationships between selenium levels in blooc plasma, liver, and muscles but much less correlation between these, on the one hand, and selenium in kidneys, on the other. The correlations between blood plasma and muscle selenium were close enough to take blood plasma values recorded from the living animal as reference from which to draw conclusions as to the muscular selenium state.

Animals↗

[Sensory physiology and biomorphology of the optic papilla: analysis of correlation in normal persons].

BACKGROUND: The aim of the present study was to investigate whether the morphological variability of the optic disc has an influence on sensory test procedures. PATIENTS AND METHODS: In 52 eyes of 52 normal persons psychophysical (perimetry, color vision, contrast sensitivity) and electrophysiological (pattern-ERG and pattern-VEP) tests and planimetric papillometry were performed. A correlation analysis was made between sensory tests and area of optic disc (1.79 to 5.2 mm2) and neuroretinal rim. RESULTS: There was no significant correlation between perimetry, color vision, pattern-ERG, pattern-VEP, spatio-temporal and temporal contrast sensitivity on the one hand and optic disc area or neuroretinal rim area on the other. CONCLUSION: Results of psychophysical and electrophysiological tests do not have to be corrected with respect to the neuroretinal rim area.

Adult↗

Validation of the SWAP-200 for diagnosing psychostructural organization in personality disorders.

BACKGROUND: The aim of the study was to investigate the validity of the prototype-matching, empirically based 200-item Shedler-Westen Assessment Procedure (SWAP-200) and its clinical utility for describing underlying dimensions of psychostructural organization and functioning. SAMPLING AND METHODS: Patients (n = 306) from two psychoanalytic out-patient departments were included. Replicatory and exploratory factor analysis, correlation and discriminant validity statistics, and canonical correlation analysis were performed. RESULTS: Replicatory factor analysis failed to reproduce the identical original factorial structure. Standard factor analysis revealed an eight-factor solution displaying a dimensional description of psychostructural personality organization (high functioning - neurotic/inhibited - borderline/emotionally dysregulated - psychotic/dissocial). Discriminant validity exists across the sample owing to high/poor psychological functioning. Canonical correlation analysis does not support the replacement of the Structured Clinical Interview for DSM-IV, but provides relevant implications for refining DSM-IV axis II. CONCLUSIONS: Support is given for the SWAP instrument in describing dimensional higher-order personality organization and psychostructural functioning.

Adult↗

Left atrial conduction along the coronary sinus during ectopic atrial tachycardia and atrial fibrillation: a study using correlation function analysis.

INTRODUCTION: Correlation function analysis was applied to endocardial electrograms to investigate conduction patterns along the coronary sinus (CS) during sinus rhythm (SR) and atrial tachycardias. METHODS AND RESULTS: Eighteen recordings were obtained from 14 patients with supraventricular tachycardias. Five atrial fibrillation (AF) recordings were compared to 10 SR recordings and 3 ectopic atrial tachycardia (EAT) recordings. The maximum correlation coefficient was used to assess similarity between signals, i.e., if they originate from the same wavefront. The cumulative time delay, calculated as pairwise summation of interelectrode time delays, was used as an indicator of activation sequence along the CS. Method validation using SR showed right-to-left conduction with high correlations in 8 of 10 recordings indicating one single wavefront. EAT recordings showed consistent left-to-right conduction with left atrial foci and right-to-left with right atrial focus and lower correlations than SR. All 5 AF recordings showed predominantly left-to-right conduction direction, also with correlations lower than SR. CONCLUSION: (1) Correlation function analysis can be used to assess agreement between signals and direction of activation spread. (2) Due to the position of CS, the results can be used to derive mechanisms of interatrial conduction. (3) Consistency in electrical activity propagation along CS is common in AF.

Algorithms↗

Familial correlations, segregation analysis, and nongenetic correlates of soy isoflavone-metabolizing phenotypes.

Particular intestinal bacteria metabolize the soy isoflavone daidzein to equol and O-desmethylangolensin (O-DMA), metabolites that can be identified in urine. Individuals that harbor bacteria capable of producing equol or O-DMA are known as equol producers (approximately 30%-50% of the population) and O-DMA producers (approximately 80%-90% of the population), respectively. The equol-producer phenotype has been associated with sex hormone-related outcomes in several studies. However, the bacteria responsible for these phenotypes have not yet been identified and factors that influence the manifestation of these phenotypes are not well understood. To evaluate familial clustering of and nongenetic factors associated with these phenotypes, 410 individuals from 112 families participated in phenotyping (3-day soy challenge and Day 4 spot urine collection). In segregation analyses of the equol-producer phenotype, the Mendelian dominant model provided the most parsimonious fit to the data, suggesting that the pattern of inheritance of the equol-producer phenotype is consistent with an autosomal dominant trait. This phenotype was positively associated with education (p trend = 0.01), but not with sex, smoking, or several dietary factors. Results of the segregation analyses of the O-DMA-producer phenotype were inconclusive; no other models provided a more parsimonious fit to the data than the general model. This phenotype was inversely associated with age in a nonlinear model (p = 0.01), positively associated with age- and sex-adjusted height (odds ratio [OR] 10-cm increase = 0.38, 95% confidence interval [CI] = 0.15, 0.95) and body mass index (kg/m(2)) (OR = 0.91, 95% CI = 0.85, 0.96), but not with sex, education, smoking, or several dietary factors. These results suggest the equol-producer phenotype may be under some degree of genetic control and that there are likely other environmental factors not evaluated in the present analysis that contribute to both of these phenotypes. These results provide a foundation for further work to refine our understanding of heritable and environmental determinants of daidzein-metabolizing phenotypes.

Female↗

Detection of tumor cells in the portal and peripheral blood of patients with colorectal carcinoma using competitive reverse transcriptase-polymerase chain reaction.

BACKGROUND: In spite of many reports, it remains unclear whether the presence of tumor cells in circulating blood flow predicts a poor prognosis. METHODS: Competitive seminested reverse transcriptase-polymerase chain reaction (RT-PCR), a technique for the quantitative detection of tumor cells, was applied to detect the presence of tumor cells in portal and peripheral blood samples from 121 patients with colorectal carcinoma and to clarify their clinical significance. This technique can detect one carcinoembryonic antigen (CEA) mRNA-expressing tumor cell in 1 x 10(5) normal lymphocytes. RESULTS: Six of 33 healthy volunteers (18%) demonstrated a positive reaction to this technique. CEA mRNA expression was detected in the portal blood in 51% of patients and in the peripheral blood in 42% of patients. The results from the two blood samples were consistent in 91% of patients. The positive expression rates for portal blood in patients with T1 tumors and those with TNM Stage I disease were 38% and 45%, respectively. The positive rate was significantly higher in patients with colon carcinoma and those with Stage III or IV disease. CEA mRNA expression, quantitatively measured (x 10(-8)/beta-actin), was 22.9 +/- 35.1 in the portal blood and 19.9 +/- 40.0 in the peripheral blood, with no statistically significant difference. A significant positive correlation was noted between portal and peripheral CEA mRNA expression levels according to Spearman correlation analysis (correlation coefficient = 0.78; P < 0.01). Multivariate analysis revealed that the positive rate and level of CEA mRNA expression in the portal and peripheral blood did not appear to be influenced by the established prognostic factors. CONCLUSIONS: The presence of circulating tumor cells might be of less value as a prognostic factor because they also can be detected in patients with early-stage colorectal carcinoma and appeared to be independent of the conventional prognostic factors.

Blood Specimen Collection↗

Catatonia as a psychomotor syndrome: a rating scale and extrapyramidal motor symptoms.

BACKGROUND: Catatonia was first described by Kahlbaum as a psychomotor disease with motor, behavioral, and affective symptoms. In keeping with this concept, we developed a rating scale for catatonia (Northoff Catatonia Scale [NCS]) with three different categories of symptoms (i.e., motor, behavioral, affective). Furthermore, the question of the relationship among catatonic symptoms, extrapyramidal motor symptoms, and neuroleptics was addressed in the present study. METHOD: 34 acute catatonic patients and 68 age-, sex-, diagnosis-, and medication-matched psychiatric control subjects were investigated on days 0, 1, 3, 7, and 21 with the NCS, with other already validated catatonia rating scales by Rosebush, Bush (BFCRS), and Rogers (MRS), as well as with scales for hypokinetic (SEPS) and dyskinetic (AIMS) extrapyramidal motor features. Validity and reliability of the new scale, factor analysis, correlational analysis, and differences between catatonic patients and psychiatric control subjects were statistically calculated. RESULTS: NCS showed high validity (i.e., significant positive correlations [p <0.0001] with the other scales, significant differences between catatonic and control subjects), high intra-and interrater reliabilities (r = 0.80-0.96), and high affective subscores. Factor analysis revealed four factors best characterized as affective, hypoactive, hyperactive, and behavioral. Catatonic scores in NCS correlated significantly with AIMS on day 0 and SEPS on days 7 and 21. There were no significant differences in catatonic (i.e., NCS, MRS, BFCRS) and extrapyramidal (i.e., AIMS, SEPS) scores between neuroleptically treated and untreated catatonic subjects. CONCLUSIONS: The following conclusions were drawn: (1) the NCS has to be considered as a valid and reliable rating instrument for catatonia; (2) catatonia can be characterized by psychomotor symptoms encompassing motor, affective, and behavioral alterations; and (3) extrapyramidal hyperkinesias like dyskinesias are apparently closely related to catatonic symptoms which, in general, seem to be relatively independent of previous neuroleptic medication.

Acute Disease↗

Optic nerve head blood flow using scanning laser Doppler flowmetry after laser in situ keratomileusis.

PURPOSE: To investigate ocular blood flow changes following laser in situ keratomileusis (LASIK) in myopic eyes. METHODS: Seventeen eyes of ten myopic patients were included in the study. Mean age of the seven men and three women was 29.1+/-2.5 years. Mean spherical equivalent refraction was -7.70+/-2.52 D. LASIK was performed with the Hansatome microkeratome and Summit SVS Apex excimer laser. Optic nerve head blood flow was measured by using the Heidelberg Retinal Flowmeter preoperatively and postoperatively at 1 day, 1 week, and 1 month. Preoperative ocular blood flow data (blood flow, volume, velocity) were compared with postoperative data using variance analysis. Correlation analysis was performed for age of patients, suction time, and ocular blood flow data. RESULTS: Mean suction time was 19+/-7 seconds. There was no significant correlation between suction time, age, and ocular blood flow. We found an increase in blood flow at the lamina cribrosa taken 1 day postoperatively (P=.04). Blood flow returned to preoperative values at the 1-week and 1-month measurements in the lamina cribrosa region. There was no significant change in ocular blood flow data in the neuroretinal rim except an increase in velocity at the lower nasal quadrant on postoperative day 1 (P=.03). CONCLUSIONS: LASIK caused a temporary increase in blood flow at the lamina cribrosa region of the optical nerve head in healthy myopic eyes. The increase in blood flow may suggest a compensatory change for maintaining blood flow in the ocular nerve head following LASIK-induced ischemia.

Adult↗

Familial resemblance of bone mineralization, calcium intake, and physical activity in early-adolescent daughters, their mothers, and maternal grandmothers.

OBJECTIVE: To describe familial relationships among bone mineral density (BMD), calcium intake, and physical activity in early-adolescent daughters, their premenopausal mothers, and postmenopausal maternal grandmothers. SUBJECTS: Healthy, early-adolescent daughter and premenopausal mother pairs (n=72) were enrolled in the study. In addition, a cohort of 22 postmenopausal maternal grandmothers were measured for comparison of related triads (n=22). DESIGN: Cross-sectional measurements of hip (three sites) and lumbar spine BMD by dual energy x-ray absorptiometry (DXA), body height and weight, menstrual function, current calcium intake, and current and past physical activity patterns were assessed using recalls and questionnaires. STATISTICAL ANALYSIS: Correlational analysis was used to establish relationships between bone characteristics and body size, menstrual function, calcium intake, and physical activity. Multiple regression analyses with backward elimination were used to examine heritability of bone characteristics in daughter-mother and mother-grandmother pairs and daughter-mother-grandmother triads. Quick cluster analysis and cross-tabulation with Pearson's chi(2) were used to evaluate familial patterns for bone characteristics and lifestyle practices. RESULTS: Height, weight, and lumbar spine BMD were significantly correlated within mother-daughter pairs. Current and past calcium intakes were not related within pairs or triads or to BMD in the daughters or the grandmothers. A weak inverse relationship between calcium intake and the hip trochanter and lumbar spine BMD was observed in the mothers (R(2)=-0.25; P=.05). Physical activity, independent of calcium intake, was strong predictor of BMD for daughters and mothers. Among the daughters, the hertiability estimates for trochanter and lumbar spine BMD were 0.56 and 0.70, respectively (P<.01). The heritability estimate for premenopausal mothers were significant for lumbar spine BMD (h(2)=0.66; P<.01). Daughter-mother-grandmother triads with low physical activity had low femoral neck BMD whereas those with high physical activity had high femoral neck BMD (P<.001). APPLICATIONS: Making physical activity a part of the daily routine, in addition to an adequate intake of calcium and bone-related nutrients, is an important goal for maintaining or improving bone health for women of all ages.

Absorptiometry, Photon↗

Assessment of left ventricular function in healthy subjects by pusled wave Doppler tissue imaging.

OBJECTIVE: To examine the clinical application of pulsed Doppler tissue imaging (DTI) for regional left ventricular function assessment in normal subjects. METHODS: We examined 50 healthy subjects (range 12-42 years, mean age 28.3 +/- 6.9 years) using pulsed Doppler tissue imaging to characterize the diastolic and systolic velocity profiles of mitral annulus. Recordings were made along the long axis in the apical 4-chamber, 2-chamber, and long apical views of 6 sites (posterior-septum, lateral, anterior, inferior, anterior-septum, posterior) at the mitral annulus. Myocardial velocities were determined with use of variance F statistical analysis. Correlation analysis was employed to test the relationship between age and mitral annular velocities. RESULTS: Both early diastolic and systolic velocities at the septum were lower than other sites. There were no differences in mitral annulus late diastolic velocities. Mean early diastolic and systolic velocities was negatively correlated with age. CONCLUSIONS: Doppler tissue imaging can directly reflect regional left ventricular function.

Adolescent↗

Usefulness of combining clinical and radiological dental findings for a more accurate noninvasive age estimation.

The aim of this study was to establish correlations of clinical and radiological dental findings, alone or in combination, with chronological age in adults. Dental findings and orthopantomograms of 984 patients (aged 20-60 years; 524 females/460 males) were analyzed. DMF-T index and distance (alveolar bone level, ABL) between cemento-enamel junction and alveolar bone margin were recorded. Additionally, clinical and radiological findings at each tooth crown and root were collected according to the actual status of destruction and restoration, and a total score for each dentition (TSD) was calculated. After univariate correlation analysis, correlation coefficients for ABL and TSD were improved by using square root (sqrt). However, the determination accuracy was still not satisfactory; 90% of the residuals were in the range of about +/-10. The present study showed that clinical and radiological dental findings could not be used, not even in combination, for accurate age estimation as a single method, but that they could support other methods.

Adult↗

Geographic distribution of environmental factors influencing human skin coloration.

Skin coloration in indigenous peoples is strongly related to levels of ultraviolet radiation (UVR). In this study, the relationships of skin reflectance to seasonal UVR levels and other environmental variables were investigated, with the aim of determining which variables contributed most significantly to skin reflectance. The UVR data recorded by satellite were combined with environmental variables and data on human skin reflectance in a geographic information system (GIS). These were then analyzed visually and statistically through exploratory data analysis, correlation analysis, principal components analysis, least-squares regression analysis, and nonlinear techniques. The main finding of this study was that the evolution of skin reflectance could be almost fully modeled as a linear effect of UVR in the autumn alone. This linear model needs only minor modification, by the introduction of terms for the maximum amount of UVR, and for summer precipitation and winter precipitation, to account for almost all the variation in skin reflectance. A further significant finding was that the effect of summer UVR seems to reach a threshold beyond which further adaptation is difficult.

Environmental Exposure↗

Translation and validation of the Chinese version of the Gastrointestinal Quality of Life Index in patients with gastric tumor.

OBJECTIVE: Patients with gastric tumor are known to have deterioration in quality of life (QOL) following surgery. However, there is no valid disease-specific self-report QOL measure for clinical practice and research designated for Chinese in Hong Kong. The current study aimed at translating and validating a Chinese version of the Gastrointestinal Quality of Life Index (C-GIQLI) for use in patients with gastric tumors after gastrectomy. METHODS: A translation of the English version of the instrument was performed. The psychometric properties of the C-GIQLI were investigated using internal consistency analysis, correlational analysis, and confirmatory factor analysis in 140 Chinese patients who had undergone surgery for gastric tumor. RESULTS: The C-GIQLI demonstrated good test-retest reliability, internal consistency, and a factor structure consistent with the measurement model of the European version of the instrument. CONCLUSION: The C-GIQLI is recommended as a valid and reliable self-report measure of QOL in patients with gastric tumor after gastrectomy.

Adult↗

Modulation of a brain-behavior relationship in verbal working memory by rTMS.

We investigated whether the brain-behavior relationship (BBR) between regional cerebral blood flow (rCBF) as measured by positron emission tomography (PET) and individual accuracy in verbal working memory (WM) can be modulated by repetitive transcranial magnetic stimulation (rTMS) of the left or right middle frontal gyrus (MFG). Fourteen right-handed male subjects received a 30-s rTMS train (4 Hz, 110% motor threshold) to the left or right MFG during a 2-back WM task using letters as stimuli. Simultaneously an rCBF PET tracer was injected and whole-brain functional images were acquired. A hypothesis-driven region-of-interest-analysis of the left and right MFG BBR as well as an explorative whole-brain analysis correlating the individual accuracy with rCBF was carried out. Without rTMS we found a negative BBR in the left but no significant BBR in the right MFG. This negative BBR is best explained by an increased effort of volunteers with an inferior task performance. Left-sided rTMS led to a shift of the BBR towards the superior frontal gyrus (SFG) and to a positive BBR in anterior parts of the left SFG. With rTMS of the right MFG the BBR was posterior and inferior in the left inferior frontal gyrus. Beyond the cognitive subtraction approach this correlation analysis provides information on how the prefrontal cortex is involved based on individual performance in working memory. The results are discussed along the idea of a short-term plasticity in an active neuronal network that reacts to an rTMS-induced temporary disruption of two different network modules.

Adult↗

Autosomal dominant cerebellar ataxia type I clinical features and MRI in families with SCA1, SCA2 and SCA3.

Sixty-five patients suffering from autosomal dominant cerebellar ataxia-I(ADCA-1) were subjected genotype phenotype correlation analysis using molecular genetic assignment to the spinocerebellar ataxia type 1, 2 or 3 (SCA1, -2 or -3) locus, clinical examination, eye movement recording and morphometric analysis of MRIs. Pyramidal tract signs, pale discs and dysphagia were more frequent in SCA1 compared SCA2 and SCA3 patients. Saccade velocity was reduced in 56% of SCA1 and all SCA2, but only in 30% of SCA3 patients. MRIs of SCA2 patients showed atrophy changes typical of severe olivopontocerebellar atrophy (OPCA). The morphological changes in SCA1 were similar but less pronounced. In contrast, SCA3 patients had only mild cerebellar and brain stem atrophy distinct from typical OPCA. The principal finding of this study is that mutations of the SCA2 and SCA3 gene cause phenotypes which can be distinguished in vivo by recording of eye movements and morphometric MRI analysis. Correlative plotting of saccade velocity and diameter of the middle cerebellar peduncle yields a clear separation of SCA2 and SCA3. Spinocerebellar ataxia type I falls into an intermediate range that overlaps with both SCA2 and SCA3. However, the clinical syndrome observed in SCA1 patients is different from that in SCA2 and SCA3.

Adult↗

Nurses who work outside nursing.

BACKGROUND: The desire to care for people, a family history of professional health care work, and security in career choice are documented reasons for entering nursing. Reasons for leaving include workload, unsafe work environments and harassment. The relationship between these factors and the time nurses spend in the profession has not been explored. AIM: This paper reports a study with people who have left nursing, to investigate why they became a nurse, how long they stayed in nursing, and their reasons for leaving. METHOD: A questionnaire was mailed to Registered Nurses currently working outside nursing, seeking respondents' reasons for entering and leaving nursing, and perceptions of the skills gained from nursing and the ease of adjustment to working in a non-nursing environment. Data analysis included descriptive statistics, exploratory and confirmatory factor analysis, correlational analysis and linear and multiple regression analysis. RESULTS: A model incorporating the factors 'altruistic reasons', 'default choice' and 'stepping stone' explained 36.2% of the variance in reasons for becoming a nurse. A model incorporating the factors 'legal and employer', 'external values and beliefs about nursing', 'professional practice', 'work life/home life' and 'contract requirements' explained 55.4% of the variance in reasons for leaving nursing. Forty-eight per cent of the variance in tenure in nursing practice was explained through personal characteristics of nurses (36%), reasons for becoming a nurse (7%) and reasons for leaving (6%). CONCLUSION: The reasons why nurses entered or left the profession were varied and complex. While personal characteristics accounted for a large component of tenure in nursing, those managing the nursing workforce should consider professional practice issues and the balance between work life and home life.

Adult↗

The relationship of serum IgG antibody titers to periodontal pathogens to indicators of the host response in crevicular fluid.

In this study; the relationship of indicators of the local host response in gingival crevicular fluid (GCF) to the serum antibody titer to periodontal pathogens was examined. 15 patients with chronic adult periodontitis were studied. GCF was collected and analyzed for the total amount of IgG, IgM, the lysosomal enzyme B-glucuronidase (BG) and alpha-2-macroglobulin (alpha 2M). At the same examination, serum from these patients was collected, and enzyme-linked immunosorbent assays used to determine the serum IgG antibody titer to a panel of 17 periodontal pathogens (Actinobacillus actinomycetemcomitans (3 strains), Bacteroides gingivalis (4), Eikenella corrodens (2), Wolinella recta, Bacteroides intermedius (3), Fusobacterium nucleatum, and 3 Capnocytophaga species). Using Spearman rank order correlation analysis, correlation coefficients were calculated to relate the 4 indicators of host response in GCF to the serum IgG antibody titer to each of the 17 micro-organisms. The mean correlation between total IgG in GCF and the serum IgG antibody titer was positive (r = +0.30), and statistically significant correlations between total IgG in GCF and serum IgG antibody titer were observed for one strain of B. intermedius and C. ochracea. A weaker positive correlation was observed for IgM (r = 0.18). In contrast, the mean correlation between total BG in GCF and the serum antibody titer was negative (r = -0.34). Statistically significant negative correlations were observed for all 3 strains of A. actinomycetemcomitans, one strain of E. corrodens and W. recta. The mean correlation for alpha 2M was r = -0.06. These data suggest that elevated BG activity in GCF, believed to be a marker for lysosomal enzyme released from polymorphonuclear leukocytes in the crevicular environment, may be associated with a reduced serum IgG antibody response to suspected periodontal pathogens. Furthermore, these findings imply that the development of a serum IgG antibody response to suspected periodontal pathogens is consistent with a protective host response.

Actinobacillus↗

Three-dimensional mapping of dislocation avalanches: clustering and space/time coupling.

There is growing evidence for the complex, intermittent, and heterogeneous character of plastic flow. Here we report a three-dimensional mapping of dislocation avalanches during creep deformation of an ice crystal, from a multiple-transducers acoustic emission analysis. Correlation analysis shows that dislocation avalanches are spatially clustered according to a fractal pattern and that the closer in time two avalanches are, the larger the probability is that they will be closer in space. Such a space/time coupling may contribute to the self-organization of the avalanches into a clustered pattern.

Journal Article↗