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PubMed2005

[Space distribution of low birth weight in Sergipe, Brazil, 1995/1998].

This study analyzes the spatial distribution of low birth weight (LBW) in the State of Sergipe, Brazil, evaluating the event as a health indicator. The analysis was based on 166,312 live births in the 75 municipalities in the State, using an ecological approach. Four methods were used: cluster analysis, correlation analysis, multiple regression analysis, and multiple comparisons (Tukey). The study shows internal homogeneity in the municipalities' health districts and in the groups resulting from the cluster analysis. Considering a 10% loss of information, seven groups were identified, two of which were residues (Aracaju and Porto da Folha). There is a downward trend in LBW in Sergipe (with a mean of 6.97% during the period), reflecting a slight improvement in quality of life. The causes suggest relations with the environment and are influenced by spatial occupation patterns. The percentage of LBW is a useful indicator of individual risk, but as a collective health indicator it does not appear capable of expressing differences between regions that do not display strong inter-variability.

Brazil↗

PubMed2004

A Novel Approach for Predicting Human Response from ATD Tests.

A methodology was developed for predicting the human response from ATD (Anthropomorphic Test Device) tests or for improving the biofidelity of the ATD response. The ATD response and human response are considered as the output of a black box system, from which the relationship between the ATD tests and human tests was established using wavelet analysis. Based on the decompositions of both responses on a wavelet packet basis, a mapping matrix is built after executing a procedure that includes de-noising and compression, energy distribution analysis, correlation analysis and regression analysis, and spectral coherence analysis and transfer function analysis. With the mapping matrix, an ATD response is modified or reconstructed into the corresponding human response. The practical use of the methodology was illustrated in the analysis of a series of lateral impact tests conducted on a horizontal impulse accelerator with an ATD and human volunteers as the test subjects. The predictions from the ATD tests using this method have attained significant improvement in biofidelity.

Journal Article↗

PubMedDate not supplied

Statistical dependence of clinical data on the chosen treatment of patients with a multivessel coronary artery disease.

BACKGROUND: In this study we tried to check which clinical data are connected with the choice of treatment in patients with a multivessel coronary artery disease. MATERIAL AND METHODS: The data of 137 patients with a multivessel coronary artery disease, were analysed retrospectively. The patients were divided into three groups: treated conservatively, CABG and PTCA. Multivessel coronary artery disease was recognised when there were atherosclerotic changes in more a 2 vessels with a not less a 2 mm in diameter. Patients with previous CABG or a left main coronary artery disease were excluded. The data were analysed by means of several methods, variance analysis, correlation analysis, discriminant functions, chi-square test and T-Student test. RESULTS: For treatment decision making in multivessel coronary artery disease of statistical significance were: the state of the left anterior descendent artery below the first diagonal branch, the state of the first diagonal branch and peripheral parts of the left anterior descendent artery and right coronary artery, the systolic function of the antero-lateral, apical and phrenic segments of the left ventricle, the global left ventricular ejection fraction in angiography and echocardiography, local systolic disturbances of the left ventricular observed in echocardiography, the coexistence of symptoms of heart failure as well as unstable angina. CONCLUSION: Treatment decision making will always depend not only on diagnostic procedures but also on all the clinical data about the patient and the experience of coworking cardiology and surgery centres.

Analysis of Variance↗

PubMed2001

An assessment of human liver-derived in vitro systems to predict the in vivo metabolism and clearance of almokalant.

The ability of various human derived in vitro systems to predict various aspects of the in vivo metabolism and kinetics of almokalant have been investigated in a multicenter collaborative study. Although almokalant has been withdrawn from further clinical development, its metabolic and pharmacokinetic properties have been well characterized. Studies with precision-cut liver slices, primary hepatocyte cultures, and hepatic microsomal fractions fortified with UDP-glucuronic acid all suggested that almokalant is mainly glucuronidated to the stereoisomers M18a and M18b, which is in good agreement with the results in vivo. Both in vivo and in vitro studies indicate that the formation of M18b dominates over that of M18a, although the difference is more pronounced with the in vitro systems. Molecular modeling, cDNA-expressed enzyme analysis, correlation analysis, and inhibition studies did not clearly indicate which P450 enzymes catalyze the oxidative pathways, which may indicate a problem in identifying responsible enzymes for minor metabolic routes by in vitro methods. All of the in vitro systems underpredicted the metabolic clearance of almokalant, which has previously been reported to be a general problem for drugs that are cleared by P450-dependent metabolism. Although few studies on in vivo prediction of primarily glucuronidated drugs have appeared, in vitro models may consistently underpredict in vivo metabolic clearance. We conclude that in vitro systems, which monitor phase II metabolism, would be beneficial for prediction of the in vivo metabolism, although all of the candidate liver-derived systems studied here, within their intrinsic limitations, provided useful information for predicting metabolic routes and rates.

Anti-Arrhythmia Agents↗

PubMed2002

Amplitopicity of the human auditory cortex: an fMRI study.

Whereas specialized frequency-encoding patterns in the human auditory cortex are generally accepted, termed tonotopicity, a similar principle of intensity encoding--amplitopicity--is debated controversially. This functional magnetic resonance imaging study describes the relationship of the activation volume and the spatial distribution of activated clusters under different sound pressure levels (SPL) across the temporal plane including the transverse temporal gyrus (TTG). Nine healthy subjects with no hearing deficiencies were investigated using an echo-planar imaging technique at 1.5 T. A boxcar stimulation paradigm was applied with a 5-Hz pulsed sine tone of 1000 Hz frequency at three SPLs of 70, 82, and 90 dB. Linear cross-correlation analysis (correlation coefficient > 0.3 corresponding to P < 0.08) of the functional data set revealed bilateral BOLD response within the auditory cortex of the nine subjects with moderate increase of activation volume for higher sound pressure levels. With increasing sound pressure a two-dimensional drift of cortical activation was observed (a) from the ventral to the dorsal edge and (b) from lateral to medial parts of TTG. This latero-medial drift therefore mimics the well-accepted principle of tonotopy for frequency-encoding neurons. This study demonstrates the existence of an amplitopic pattern of intensity-encoding neuronal clusters that in part resembles the tonotopic distribution of frequency-encoding neurons. This finding has to be integrated into the understanding of the auditory organization for the interpretation of higher auditory functions such as sound perception or speech.

Acoustic Stimulation↗

PubMed2004

[A follow-up study on dietary factors of kidney stones in Bao'an district, Shenzhen City].

OBJECTIVE: To evaluate the major dietary factors of kidney stones in Bao'an District of Shenzhen City and provide a scientific base for further effective prevention of kidney stones. METHODS: Following the process of stratified cluster random sampling in Bao'an district, a cross-sectional study (July-Aug, 2000) was conducted for collecting the base-line data on kidney stones from a population of permanent residents who were over 15 years old, exclusive of those who had had kidney stones or could not correctly respond to the questionnaire review. Then, a follow-up survey (July-Sept, 2002) for incident kidney stone cases was carried out among those residents. The methods for measurement included questionnaire and face-to-face interview, clinical examination and abdominal ultrasonography. All the investigators and interviewers were trained for the field work. And the data processing, dataset and analyses were performed using Visual-Fox 6.0 and SAS 6.12. The risk factors of kidney stoned were comprehensively analyzed for dietary, life style, and family history of stones. The statistical analyses included case-control comparison, factor analysis, correlation analysis, cluster analysis and logistic regression. RESULTS: There were 305 kidney stones patients among 4552 follow-up members, the cumulative incidence of 2 years was 6.92%. The kidney stones were associated with the factors: menopause, RR=2.433; family history of stones, RR=1.544; sea foods, the RR (5-7 times/week vs < or = 1-2 times/month) was 9.032; fruits, the RR (< or = 1-2 times/month vs > or = 1-2 times/week) was 2. 249; sweet foods, the RR (5-7 times/week vs 1-2 times/week) was 2. 568; bean and bean products, the RR (5-7 times/week and < or = 1-2 times/month vs 1-2 times/week) was 2.184 and 1.689. CONCLUSION: Changing the inappropriate habitual eating patterns and generalizing the use of proportioning dietary should be the main measures to prevent kidney stones.

Adolescent↗

PubMed1987

[Simultaneous analyses of the Freiburg Personality Inventory short form, the Eysenck Personality Inventory, the Giessen Test and Berger Scales--a contribution to the diagnostic value of the scales in assessing self acceptance and acceptance of others].

To verify the diagnostical value of the German version of the Berger scales for assessing self acceptance and acceptance of others, the scales and the short form of the "Freiburger Persönlichkeits Inventar" (FPI-K), the German version of the EPI, and the Giessen-Test were presented to a sample of 107 subjects. The data were evaluated by item analysis, correlational analysis, factor analysis, and NMDS. The results--in some degree a replication of earlier studies--prove the practicability of both constructs: The self acceptance scale assesses a positive self-image with a strong extraverted component, the acceptance of others scale shows negative relations to the aggression scales of the FPI-K. Besides this the NMDS can demonstrate a component of social desirability. The integration of both constructs into traditional concepts of personality is discussed in connection with the NMDS.

Humans↗

PubMed2006

[Computer modeling correlation between the entering wound and the final position of the metallic intraocular foreign body].

AIM: The aim of this study was to establish the correlation coefficient between given parameters of the entering wound and final position of the metallic intraocular foreign body. MATERIAL AND METHODS: Fifty patients (50 eyes) with a penetrating injury of the eye and present metallic intraocular foreign body were included in this study. Clinically found data of the entering wound and final position of the intraocular foreign body (IFB) as well were transformed with a computer model into the three-dimensional parameters. Both parameters were statistically evaluated by means of correlation analysis, and correlation coefficient and determination coefficient were calculated. RESULTS: The extent of correlation between two variables is called correlation coefficient. The coefficient values range between -1 to +1. The closer is the calculated value to ranges (to -1 or to +1) the more are the two variables more correlated. The coefficient of determination values range from 0 to +1. The closer the results are to +1, the better the model describes the dependence between the two variables. The results obtained by means of correlation analysis were for the correlation coefficient 0.454, and for the coefficient of determination 0.6411 respectively. CONCLUSION: Results of the correlation analysis show that the knowledge of coordinates of the entering wound has no prediction value for final position of the foreign body in the eye. These two variables are not correlated and so the accurate final position of the foreign body cannot be predicted. The final position of the intraocular metallic foreign body is probably influenced by biophysical factors not included in this study.

Biomechanical Phenomena↗

PubMed2001

[Analysis of correlation between physical training and autonomic function by using multivariate analysis: establishing an indicator of health].

The purpose of this study is to assess the effects of physical training on autonomic nervous function. Twenty-two healthy subjects(12 males and 10 females) participated in this study. We inquired contents of the exercise for each subject. Continuous ECG was recorded during 320 seconds at supine resting. Respiratory rhythm was fixed at 0.25 Hz(15 time/min). On the basis of spectral analysis of heart rate variability, the autonomic nervous function was assessed by low frequency power(LF: 0.06-0.13 Hz) and high frequency power(HF: 0.16-0.50 Hz). The predominance of sympathetic nervous activity were indicated by the LF/HF and LF-HF. Relationship between physical training and autonomic function was analyzed by using multivariate analysis(partial correlation analysis). As the results, LF power and LF-HF negatively correlated with training time per day, energy expenditure per day, energy expenditure per week, and total energy expenditure, respectively(p < 0.05). HF power positively correlated with energy expenditure per day, energy expenditure per week, and total energy expenditure, respectively(p < 0.05). These results indicate not training time but energy expenditure alters the autonomic nervous function. This index may be useful for evaluating training effect on the promotion of health.

Adult↗

PubMed2006

CorrXpression--identification of significant groups of genes and experiments by means of correspondence analysis and ratio analysis.

CorrXpression is a stand-alone desktop application for the identification of significant genes within collections of microarrays. The software combines three methods in two steps of analysis: correspondence analysis (CA), ratio analysis and correlation analysis. The graphical interface of CorrXpression visualizes the result of the CA with a biplot and the expression of selected genes in dependency of the experiments as bar diagrams. The CA-plot is an excellent tool for visualization and evaluation of data and results of ratio analysis and correlation analysis. The input data are selected from a database or from appropriate ASCII files.

Animals↗

PubMed2006

Relationship of remote sensing normalized differential vegetation index to Anopheles density and malaria incidence rate.

OBJECTIVE: To study the relationship of remote sensing normalized differential vegetation index (NDVI) to Anopheles density and malaria incidence rate. METHODS: Data of monthly average climate, environment, Anopheles density and malaria incidence rate, and remote sensing NDVI were collected from 27 townships of 10 counties in southeastern Yunnan Province from 1984 to 1993. The relationship of remote sensing ecological proxy index, NDVI, to Anopheles density and malaria incidence rate was studied by principal component analysis, factor analysis and grey correlation analysis. RESULTS: The correlation matrix showed that NDVI highly correlated with Anopheles density in 4 townships of Mengla, Jinghong, and Yuanjiang counties, but in other 23 townships the relationship was not clear. Principal component and factor analyses showed that remote sensing NDVI was the representative index of the first principal component and the first common factor of Anopheles density evaluation. Grey correlation analysis showed that in rainy season NDVI had a high grey correlation with Anopheles density and malaria incidence rate. The grey correlation analysis showed that in rainy season the grey degree of NDVI correlated with Anopheles. Minimus density was 0.730, and 0.713 with Anopheles sinensis density, and 0.800 with malarial incidence rate. CONCLUSION: Remote sensing NDVI can serve as a sensitive evaluation index of Anopheles density and malaria incidence rate.

Animals↗

PubMed2025

Reduced mean platelet volume (MPV) as an inflammatory marker in Chinese women with polycystic ovary syndrome: a case-control study.

BACKGROUND: Low-grade chronic inflammation is observed in women with polycystic ovary syndrome (PCOS). A recent genome-wide association study (GWAS) suggested that several inflammation marker levels were altered in the blood routine tests in PCOS patients and such changes were associated with variant gene clusters. Therefore, inflammatory marker alterations in the blood routine tests are significant and might be involved in the onset as well as progression of PCOS. Compared with other markers, these inflammatory markers in the blood routine tests are less expensive and easier to detect. Very few studies have evaluated the changes in platelet indicators like platelet count and mean platelet volume (MPV) in Chinese women with PCOS. The aim of the study was to investigate the changes in platelet-related inflammatory indices in Chinese women with PCOS. METHODS: The study included 299 women aged 18–47 with PCOS and 481 healthy women as the control group. We conducted propensity score matching to refine our dataset, utilizing the ‘Matching’ package in R to match cases with the disease to controls. Correlation analyses were performed using Pearson correlation analysis. Partial correlation analysis was used to analyse the correlation between MPV and the indicators after adjusting for age, body mass index (BMI) and waist circumference (WC). Binary logistic regression (forward-wald) was used to evaluate if the relationship between MPV and PCOS was independent of obesity, insulin resistance (IR), and hyperandrogenism. RESULTS: After matching the age, BMI, and WC of the two groups, high-sensitivity CRP (hs-CRP), white blood cell counts (WBCs), lymphocytes, platelets and great platelet count (GPC) were significantly higher (P = 0.007, 0.022, 0.011, 0.014, and 0.000, respectively), and mean platelet volume (MPV) and platelet distribution width (PDW) were significantly lower in PCOS patients compared with the control group (P = 0.000, 0.016, respectively). Neutrophils, neutrophil-to-lymphocyte ratio (NLR), and platelet hematocrit (PCT) did not show statistically significant differences between the two groups (P = 0.196, 0.480, 0.646, respectively). Decreased MPV was independently associated with the occurrence of PCOS (P = 0.005, OR = 0.770, 95% CI, 0.641–0.925). MPV was negatively correlated with total testosterone (TT), free testosterone (FT) and total cholesterol (CHOL) levels after correcting for age and obesity (r = -0.149, P = 0.000; r = -0.093, P = 0.010; r = -0.081, P = 0.025; respectively). CONCLUSIONS: Chinese PCOS patients have significantly reduced MPV as an inflammatory indicator independent of obesity, IR, and dyslipidemia.

Humans↗

PubMed2000

Analysis of correlated motion in antibody combining sites from molecular dynamics simulations.

The crystal structures of the NC6.8-antisweet taste ligand complex and the uncomplexed antibody structures display significant differences in the conformations of residues in the combining site. A molecular dynamics method was employed to understand the flexibility and correlated motion of key combining site residues in the uncomplexed antibody. The simulations reveal that residues that show conformational differences between the complex and uncomplexed structures display strong dynamical correlations. Extensive analysis of the dynamics trajectory using time correlation methods is presented.

Acetates↗

PubMed2001

Organ procurement organization (OPO), best practices.

There are currently 59 organ procurement organizations (OPOs) in the United States which serve their assigned geographic areas with variable productivity. Knowledge of organizational characteristics, programs and practices of more successful OPOs may be useful to increase the productivity of less successful OPOs. A preliminary survey of all OPO executive directors in the United States ascertained the most important beneficial and detrimental factors affecting their success. Site visits were then conducted at OPOs based on a selection process utilizing population size, geographic location, minority population, donors per million population and donors per thousand deaths among potential donors. All OPOs were categorized and the highest ranking OPOs in each of seven categories, based on 4 years of national data, were selected for the site visits. Regression analysis and correlation analysis using Pearson's product-moment correlation were performed. The survey to identify the important factors was returned by 47 (77%) of 61 OPOs existent in 1999. The most important beneficial factors identified by responding OPOs were adequate staffing and experience, allocation of responsibilities, hospital development and leadership. The most important detrimental factors were inadequate staffing and experience, poor donor hospital/transplant center/ OPO relationships and failure in the consent process. Site visits of the highest-ranking OPOs demonstrated all had respected, experienced leadership focused on the donation process; efficient mechanisms for resolving allocation or transplant center conflicts; systems for monitoring activity and tracking outcomes; excellent communication between OPO and transplant centers; open internal communication at all levels of the OPO; immediate, on-site response to vascular donor referrals; and volunteer support of public and/or professional education. Regression and correlation analysis demonstrated that as minority population increases, OPO performance declines (P < 0.03). Moreover, independent OPOs were associated with poorer performance regardless of minority population (P < 0.05). All of the successful OPOs visited had strong leadership, excellent donor hospital and transplant center relationships, well-developed communication and innovative methods to deal with their minority populations. Application of these practices within all OPOs could significantly enhance organ donation.

Humans↗

PubMed2006

Relationship between true fasting plasma insulin level and angiographic characteristics of coronary atherosclerosis.

BACKGROUND: Reports about the relationships between specific insulin concentration and coronary heart disease risk are controversial. HYPOTHESIS: The objective of this study was to examine the association between insulin level and the severity of coronary atherosclerosis. METHODS: The study population consisted of 507 consecutive patients (376 men and 131 women) who underwent coronary angiography for suspected or known coronary atherosclerosis. The patients' habits of smoking and drinking were investigated, and anthropometric measurements including body mass index, systolic and diastolic blood pressures, as well as plasma measurements including lipids and blood glucose were taken. The true insulin level was measured using a highly sensitive two-site sandwich ELISA. The severity of coronary atherosclerosis was defined by the Gensini score system. The statistical methods including Kruskal-Wallis test, chi-square analysis, Spearman correlation analysis, and multivariate stepwise linear regression analysis were employed to explore the relationship between specific insulin level and coronary atherosclerosis. RESULTS: When the Gensini score was examined as a categorical variable classified by tertile values, subjects with a high Gensini score had significantly higher values of fasting plasma specific insulin level (p = 0.022). The Spearman correlation analysis suggest that the Gensini score correlated significantly with true insulin (mIU/l) (r = 0.095, p = 0.033). However, the results from the multivariate stepwise linear regression analysis show that the association between specific insulin level and severity of coronary atherosclerosis lost its significance. CONCLUSIONS: The level of plasma fasting specific insulin was associated significantly with the severity of coronary atherosclerosis, as measured by Gensini score, but hyperinsulinemia showed no association with the severity of coronary atherosclerosis in multivariate analyses.

Aged↗

PubMed2005

Chemometrics methods for the investigation of methylmercury and total mercury contamination in mollusks samples collected from coastal sites along the Chinese Bohai Sea.

The development and application of chemometrics methods, principal component analysis (PCA), cluster analysis and correlation analysis for the determination of methylmercury (MeHg) and total mecury (HgT) in gastropod and bivalve species collected from eight coastal sites along the Chinese Bohai Sea are described. HgT is directly determined by atomic fluorescence spectrometry (AFS), while MeHg is measured by a laboratory established high performance liquid chromatography-atomic fluorescence spectrometry system (HPLC-AFS). One-way ANOVA and cluster analysis indicated that the bioaccumulation of Rap to accumulate Hg was significantly (P<0.05) different from other mollusks. Correlation analysis shows that there is linear relationship between MeHg and HgT in mollusks samples collected from coastal sites along the Chinese Bohai Sea, while in mollusks samples collected from Hongqiao market in Beijing City, there is not any linear relationship.

Analysis of Variance↗

PubMed1999

Comparison of two quality-of-life instruments for cancer patients: the functional assessment of cancer therapy-general and the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-C30.

PURPOSE: To compare two quality-of-life (QOL) questionnaires for cancer patients, the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-C30 (EORTC QLQ-C30) and the Functional Assessment of Cancer Therapy-General (Fact-G), on the basis of empirical data. PATIENTS AND METHODS: Two hundred forty-four patients with a diagnosis of breast cancer or Hodgkin's disease completed both the EORTC QLQ-C30 and the FACT-G (German language version) during the same session. Questionnaire data were analyzed on a subscale basis using correlation analysis, canonical correlation, and multiple linear regression. RESULTS: Correlations between corresponding subscales of the FACT-G and the EORTC QLQ-C30 ranged from r =.14 for the social domain (very poor agreement) to r =.66 for the physical domain (good agreement), with r values for the other domains lying between these extremes. Canonical correlation analysis for the two sets of subscales revealed that overall agreement between the two instruments was only moderate (first canonical correlation coefficient r =.85, but overall redundancy less than 40%). Of the five FACT-G subscales, only one, physical well-being, was well represented by the EORTC QLQ-C30 subscales (multiple linear regression, R(2) =.67). Only three of eight EORTC QLQ-C30 subscales (physical functioning, global QOL, general symptoms) were represented fairly well by FACT-G subscales (R(2) =.43 to.60). The lowest R(2) values (<.15; ie, virtually no representation by the other instrument) were found for the FACT-G social well-being and relation with doctors and EORTC QLQ-C30 cognitive functioning subscales. CONCLUSION: For the sample investigated, the EORTC QLQ-C30 and the FACT-G were found to measure markedly different aspects of QOL, despite considerable overlap. Replicability provided, this implies that neither of the two QOL instruments can be replaced by the other and that a direct comparison of results obtained with the two instruments is not possible.

Adult↗

PubMed1983

Structural changes in tubulin sheets upon removal of microtubule-associated proteins.

Zinc-induced tubulin sheets without microtubule-associated proteins (MAPs) were assembled from tubulin purified by phosphocellulose chromatography. Large, open sheets were obtained in five-minute incubations at pH 5.7. Electron micrographs of negatively stained sheets showed a protofilament arrangement similar to that observed for zinc-induced sheets with MAPs but with altered lattice parameters. The spacings measured from optical diffraction patterns demonstrated that the protofilaments were 2.2 A closer together in the sheets without MAPs. Each MAP-free sheet was also divided roughly in half by a discontinuity which was parallel to the protofilaments and the relationship between the two domains was deduced from computed transforms. Two-dimensional image processing was carried out by conventional Fourier techniques and by correlation analysis. The correlation analysis improved the reconstructions in this application, with the resolution limited by the inherent properties of the negative stain method to about 14 A. A prominent feature of the computed reconstructions was an alternation of light and dark protofilaments due to differential staining, as revealed by a study of folded sheets. Neighboring protofilaments are related by a 2-fold screw axis, as they are in zinc-induced sheets with MAPs, but the symmetry is masked by the differential staining. The major effect of MAP removal on the structure of the sheets is that the bilobed structure of alternate tubulin subunits is no longer observed. This observation and the closer spacing of protofilaments is consistent with the postulate that some of the MAP molecules lie in the groove between protofilaments and bind to several tubulin dimers.

Animals↗