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PubMed2006

Combining markers of nephrotoxicity and hepatotoxicity for improved monitoring and detection of chronic alcohol abuse.

BACKGROUND: Most of the commonly used markers of chronic alcohol abuse reflect alcohol hepatotoxicity; however, such abuse is deleterious to the kidneys as well. Combined use of serum markers of liver origin and urinary markers of kidney origin may be of diagnostic advantage. METHODS: The study was performed in 73 male alcoholics undergoing detoxification and 36 male alcoholics who had maintained abstinence for > or =6 weeks. Factor analysis, discriminant analysis and receiver operating characteristic (ROC) analysis were used to assess the discriminative power of two urinary markers of alcohol nephrotoxicity, namely beta-N-acetylhexosaminidase (Hex, EC 3.2.1.52) and alanine aminopeptidase (EC 3.4.11.2), and of three serum markers of alcohol hepatotoxicity, namely aspartate aminotransferase (EC 2.6.1.1), alanine aminotransferase (EC 2.6.1.2) and gamma-glutamyltransferase (GGT, EC 2.3.2.2), and of their quantitative combinations. RESULTS: The discriminative power of the urinary markers matched that of the serum markers. Hex and GGT appeared to be the best for discriminating the study groups. Their combination given by the equation G&H=0.62 x ln(GGT)+0.72 x ln(Hex) showed excellent discriminative ability (ROC area under the curve 0.92) that was significantly higher than that of any single marker in this report, indicating superior diagnostic accuracy of the compound marker. CONCLUSIONS: Kidney-derived urinary markers, particularly Hex, can complement or replace, if necessary, serum markers of chronic alcohol abuse that relate to alcohol hepatotoxicity. The compound marker proposed seems a promising tool for the monitoring and perhaps detection of chronic alcohol abuse and warrants further studies.

Adult↗
PubMed1982

Classification and misclassification in sexing the Black femur by discriminant function analysis.

Stepwise discriminant function analysis for sex assessment was applied to 130 North American Black femora. The measurements included femoral length and three midshaft dimensions likely to be preserved in archaeologically-derived and forensic remains. The method correctly assigned sex for 76.4% of the sample (range 70.8-81.5%). This compares favorably with results achieved with other skeletal parts; it also compares favorably with results using the femur in sexing other racial groups. Among our other conclusions are: (1) a "general size factor" is one of major significance in correct classification and in misclassification of sex, and most misclassified individuals are anomalous for this factor; (2) the inconsistency in the relation between circumference and femoral length, which characterizes the remaining misclassified individuals, suggests that anomalous functional demands of body weight/musculature are at fault, and affect circumference more than length; and (3) discriminant function analysis of the same variables in Whites produced similar results, suggesting that sex overrides race in sex assessment; this was confirmed by cross-validating the predictive accuracy of Black discriminant function coefficients on White data, and vice versa.

Analysis of Variance↗
PubMed1993

Perceiving oneself as 'disabled' or as having a 'disabling condition': a discriminant function analysis.

Using discriminant function analysis, information obtained in telephone interviews with a national, random sample of 1000 Americans with self-ascribed disabling conditions was analysed to cast light on differences between individuals who did and did not consider themselves 'disabled'. Maximum separation between the two groups was attained by an equation of six descriptors. In the order of their importance they were (1) the belief that others who knew them well considered them disabled, (2) self-rated severity of disability, (3) identification with others with disabilities, (4) gender, (5) perceived extent of limitations, and (6) needing equipment to walk. Somewhat different equations were generated for sampled men and women. An appreciation of these results in terms of a person's fit with his or her environment is offered.

Adolescent↗
PubMed1993

Techniques to identify clinical contexts during automated data analysis.

The interpretation of automatically collected data to produce intelligent alarms and identify particular conditions is nearly impossible without identifying the specific context in which the data are obtained. Shifts in clinical context occur because of changes in the patient's physiologic state, or due to the passage of time, or due to changes imposed by therapeutic intervention such as surgery. Techniques to identify such changes in clinical context are discussed with particular attention to the application of cluster analysis, discriminant analysis, and statistical predictors. An example of these analyses applied to EEG data is presented, showing an unexpected hysteresis of EEG behavior in response to an hypoxic challenge.

Cluster Analysis↗
PubMed1991

[Effect of the ACE-inhibitor captopril on the blood pressure and kidney function of patients with essential and renal hypertension].

We retrospectively analysed the effects of a 12-month treatment with captopril (Tensiomin) in 46 patients. All of the patients had hypertension lasting for years (9 essential, 37 with chronic renal failure), 32 of them had proteinuria. Captopril was given in addition to, or in exchange for, other antihypertensive drugs. Under treatment with ACE-inhibitors, a small but significant decrease in diastolic blood pressure (0.4 torr/month) and in proteinuria (0.19 g/month) was seen (regression analysis). Discriminant analysis showed proteinuria and diastolic blood pressure to be the more modifiable, the younger the patients, the higher the proteinuria at the beginning and the longer the history of hypertension. Serum creatinine, blood urea nitrogen, serum protein and serum potassium did not change.

Adult↗
PubMed1998

Life control and health in view of qualitative and quantitative research.

In this paper the experiences of life control and health of Finnish people are described and compared by reference to two studies with different methodologies. The goal of the qualitative study was to describe and understand the human being's health as an individual way of existence on the basis of life descriptions. The qualitative data were gathered through thematic interviews (n = 60, men and women, aged 30-50 years). The data were analyzed with the grounded theory method. The analysis showed life control to be a core category that characterizes health experiences. On the basis of the analysis, the content of concept of life control was defined to describe the data. The goal of the quantitative study was to produce information on life control among young males, their health, health behaviour, experiences of stress and life situations as well as the associations between these dimensions. The definition of life control was based on Antonovsky's theory of sense of coherence and on the study of Söderqvist and Bäckman. The quantitative data were gathered with questionnaires from 2500 (response rate 60%). The data were processed using cross-tabulation and multivariate data analysis (discriminant analysis). The connections between life control and health were obvious in both studies. To a certain extent the results were parallel, but there were also some differences which are discussed here as a starting point for developing further the research on life control and health in the nursing science context.

Adult↗
PubMed1997

Classification strategies for the grading of renal cell carcinomas, based on nuclear morphometry and densitometry.

The various grading systems proposed for renal cell carcinomas all suffer from problems related to inter-observer variability. Some of these grading systems are based, either partially or wholly, on morphonuclear criteria, such as nuclear size and shape, anisonucleosis, and chromatin pattern. These criteria can be quantitatively (and thus objectively) evaluated by means of the computer-assisted microscopic analysis of Feulgen-stained nuclei. In the present work, 39 quantitative variables, including two morphometric, 28 chromatin pattern-related, and nine DNA ploidy level-related, were computed for 65 renal cell carcinomas. The actual diagnostic information contributed by each variable was determined by means of multifactorial statistical analysis (discriminant analysis) and two artificial intelligence-related methods of data classification (the decision tree and production rule methods). The results show that quantitative information, as provided by the computer-assisted microscopy of Feulgen-stained nuclei and analysed by means of artificial intelligence-related methods of data classification, contributes significant diagnostic information for the grading of renal cell carcinoma, thus reducing the problem of inter-observer reproducibility.

Adult↗
PubMed1989

[Survey of what dental students feel regarding their profession (3). The relation with their self concept].

The present survey was undertaken to find out how dental student feel about their profession and what type of the self concept they have. The subjects were 263 students in the 5th and 6th grades of dental school, Aichi-Gakuin University. The pattern of self concept as dental students or dentists was classified into three types, based on a survey of twenty statements test. These types were positive, negative and neutral. The results were as follows: 1. In both the 5th and 6th grades, statements about "present satisfaction as a dental student", in the 5th grade, "progress of university entrance examination", and in the 6th grade, "feelings about the scholastic side of dentistry", were strongly related to their type of self concept. But in both the 5th and 6th grades, there were few related statements about "the motive for entering the dental school" and "occupational choice after graduation". 2. In the result of the multivariate analysis Discriminant Analysis by the Second Class of Hayashi's Quantifying Theory, those students who were graded as "positive" had the following characteristics: (1) Regarding entrance examinations, they took only one examination for dental school when they entered. (2) When choosing dentistry as their occupation, they had not thought of it as a "self supporting occupation" or "occupation of high social standing". (3) Their present interest is learning about dentistry. (4) After their graduation from dental school, they would like to be professional dentists or, a practicing dentists or students of clinical dentistry in the hospital of the dental school.

Adult↗
PubMed1988

A multivariate analysis method for discriminating protein secondary structural segments.

Using discriminant analysis, three types of protein secondary structure segments--helices, beta-strands and coils--are discriminated by amino acid sequence information alone. A variable in the discriminant analysis is defined by the amino acid index used to represent the sequence data and by the calculation method used to extract a feature in this representation. Thus, the three types of secondary structure segments derived from a set of non-homologous proteins from the Protein Data Bank are analyzed by 888 variables, which correspond to the mean, standard deviation, 3.6-residue periodicity and 2-residue periodicity for the numerical profiles determined from 222 published amino acid indices. These variables are combined to obtain best discrimination of the three types of segments. When up to three variables are combined, the best discrimination rate was 75%. The variables selected consist of the mean of alpha propensity (or turn propensity), the mean of beta propensity, and the 3.6-residue periodicity of hydrophobicity. This variable selection procedure can also be applied to other types of discrimination problem, once groups of sequence data are properly organized.

Amino Acid Sequence↗
PubMed2006

Application of chemometrics in river water classification.

The main aim of this work is focused on water quality classification of the Brda river (Poland) and evaluation of pollution data obtained by the monitoring measurement during the period 1994-2002. The study presents the application of selected chemometric techniques to the pollution monitoring dataset, namely, cluster analysis, principal component analysis, discriminant analysis and factor analysis. The obtained results allowed to determine natural clusters and groups of monitoring locations with similar pollution character and identify important discriminant variables. Chemometric analysis confirmed the classification of water purity of the Brda river made by the Inspection of Environmental Protection but the results showed more differentiation between monitored locations. This enables better evaluation of the water quality in a monitored region. On the basis of the chemometric approach, it was also found that some locations were under the high influence of municipal contamination, and some others under the influence of agriculture (discharges from fields) within the observed time period.

Agriculture↗
PubMed1977

[Laboratory diagnosis of liver and biliary tract disease].

Of a greater number of biochemical tests in hepatobiliary diseases by means of methematico-statistical methods (calculation of specificity and sensitiveness, variance analysis, discrimination analysis with following discrimination experiments) the parameters should be established which in a step programme with multivariate observation and non-discriminated approach give the best possible information. The recognition of patients with liver diseases (preliminary diagnostics) is at nearly 94% possible with a scale comprising GOT, AAP, some relevant clinical data (touch findings, jaundice, hepatic skin signs) and the hepatitis B-antigen. In non-discriminated approach according to our findings the following scale should not be trangressed: GPT, GOT (compare preliminary diagnostics), LAP, AP, AAP (compare preliminary diagnostics), cholesterol, TTT, bilirubin, beta-GC. As to aimed questionings the bromsulphalein test belongs to the enlarged basic scale.

Biliary Tract Diseases↗
PubMed2004

Comparison between cachaça and rum using pattern recognition methods.

The differentiation between cachaça and rum using analytical data referred to alcohols (methanol, propanol, isobutanol, and isopentanol), acetaldehyde, ethyl acetate, organic acids (octanoic acid, decanoic acid, and dodecanoic acid), metals (Al, Ca, Co, Cu, Cr, Fe, Mg, Mn, Ni, Na, and Zn), and polyphenols (protocatechuic acid, sinapaldehyde, syringaldehyde, ellagic acid, syringic acid, gallic acid, (-)-epicatechin, vanillic acid, vanillin, p-coumaric acid, coniferaldehyde, coniferyl alcohol, kaempferol, and quercetin) is described. The organic and metal analyte contents were determined in 18 cachaça and 21 rum samples using chromatographic methods (GC-MS, GC-FID, and HPLC-UV-vis) and inductively coupled plasma atomic emission spectrometry, respectively. The analytical data of the above compounds, when treated by principal component analysis, hierarchical cluster analysis, discriminant analysis, and K-nearest neighbor analysis, provide a very good discrimination between the two classes of beverages.

Acetaldehyde↗
PubMed2005

Use of chemical profiling to differentiate geographic growing origin of raw pistachios.

The objective of this study was to demonstrate the feasibility of chemical profiling methods combined with multivariate methods to differentiate the geographical growing regions of pistachios (Pistachia vera). Elemental analysis (Ba, Be, Ca, Cu, Cr, K, Mg, Mn, Na, V, Fe, Co, Ni, Cu, Zn, Sr, Ti, Cd, and P) of pistachios samples was performed using inductively coupled plasma atomic emission spectrometry. Analysis of inorganic anions and organic acids (selenite, bromate, fumarate, malate, selenate, pyruvate, acetate, phosphate, and ascorbate) of pistachio samples was performed using capillary electrophoresis. Bulk carbon and nitrogen isotope ratios were performed using stable isotope MS. There were nearly 400 pistachio samples analyzed from the three major pistachio growing regions: Turkey, Iran, and California (United States). A computational evaluation of the trace element data sets was carried out using statistical pattern recognition methods including principal component analysis, canonical discriminant analysis, discriminant analysis, and neural network modeling. Several linear discriminant function models classified the data sets with 95% or higher accuracy. We report the development of a method combining elemental analysis and classification techniques that may be widely applied to the determination of the geographical origin of foods.

Analysis of Variance↗
PubMed1981

The role of modeling methods in medical diagnosis.

Modeling methods in medical diagnosis are concerned with medical information processing as it pertains to utilizing biological modeling methods to facilitate patient care. Major considerations in this particular area are (1) the classification problem related to the establishment of disease entities-the taxonomy problem, and (2) the diagnosis of diseases. Available are properties, criteria, signs, symptoms, and manifestations of diseases that have been cumulated and categorized by clinicians and researchers. The problem is to optimally utilize the information content of a sign or set of signs in the practice of patient care as pertaining to the medical diagnosis problem. Some mathematical approaches implemented to facilitate such analyses include cluster analysis, discriminant analysis, Bayesian methods, computer approaches, game theory, information theory, stochastic representations, stepwise procedures, decision analysis, and pattern recognition techniques. Each of these has been studied in depth by numerous researchers advocating computer applications in medicine. Here we discuss the scope and limitations of utilizing modeling methods as a viable approach to interpreting vast amounts of biological data collected on a single patient during an encounter. We consider the following: (1) limitations associated with modeling methodologies; (2) levels of responsibilities, ranging over logging, summarizing, reporting, monitoring, and therapy selection; and (3) operational strategies and considerations as they affect hardware logistics, the actual algorithm utilized, and implementation of these sophisticated analysis systems.

Decision Theory↗
PubMed1992

Heart rate variability in normal sleeping full-term and preterm neonates.

To assess maturation of the Autonomic Nervous System (ANS) and sleep states, Heart Rate Variability (HRV) was studied in 24 healthy sleeping newborns, aged from 31 to 41 weeks, conceptional age (CA). Spectral analysis of the interbeat interval (RR) signal, was performed by Short-Time Fourier Transform, in three frequency bands: high (HF), of purely vagal origin, mid (MF), and low (LF), vagal and sympathetic, thus allowing evaluation of both branches of the ANS, observed in Active Sleep (AS = REM Sleep) and in Quiet Sleep (QS = nREM Sleep). Principal Component Analysis, Discriminant Analysis, and hypothesis tests were used to investigate the evolution of spectral variables and their relation with sleep states. HF, MF, LF, and mean RR all increased with age; the differences from the premature to the full-term group, were more marked, as a whole, in AS than in QS. HF showed the highest increase from the premature (31-36 weeks CA) to the intermediate (37-38) group, whereas LF showed equal differences from the premature to the intermediate, and from the intermediate to the full-term (39-41) groups. These results suggest a steep increase in vagal tone at 37-38 weeks CA, with stability afterwards, and a more regular increase in sympathetic tone from 31 to 41 weeks CA.

Analysis of Variance↗
PubMed1999

Fatty acids including trans content of commercial bakery products manufactured in Spain.

Fifteen samples of the most common industrial bakery products sold in Spain were analyzed for their fatty acid composition. Saturated fatty acids occurred in the largest proportions in all samples (mean = 52.8%), followed by monounsaturated (mean = 23.5%) and polyunsaturated fatty acids (mean = 17.2%). A small percentage of trans fatty acids, which were found in all samples, showed a mean value of 5.7%. According to their fatty acid composition, that is, their saturated, monounsaturated, and polyunsaturated fatty acid contents, the statistical analysis (discriminant analysis) showed three groups of samples, suggesting that the fat incorporated in these samples was obtained from different sources.

Chromatography, Gas↗
PubMed1990

[Tissue characterization of the liver using ultrasound attenuation in an animal experiment].

Frequency-dependent attenuation of sound is considered a characteristic parameter of the interaction between sound and tissue and has been studied particularly in the liver via many different techniques. Due to the relatively wide scatter of the measured single values, especially in pathological liver samples, a clinically feasible application of the procedure has not yet been found. In the present paper, the suitability of the frequency-dependent coefficient of sound attenuation for tissue characterization with comparable experimental conditions in vitro was tested in a statistically representative collection of histologically defined tissue specimens of rat liver. Several statistical procedures were used (cluster analysis, discrimination analysis). Normal livers can be usually distinguished from pathological specimens by means of the frequency-dependent coefficient of sound attenuation with only slight scatter of the individual values. Although the latter differ on the average from normal specimens, they diverge considerably in respect of single values resulting in significant differences only in case of extensive tissue damage (cirrhosis). On the basis of tissue classifications in clinical and pathological use, only a rough tissue differentiation is possible. By using additional parameters of the interaction between sound and tissue, sonographic differentiation of pathologically changed tissue my be improved.

Animals↗
PubMed1998

Analysis of blood chemistry and hearing levels in a sample of older persons.

OBJECTIVE: As part of an ongoing study of presbyacusis, the relationship between blood chemistry levels and hearing levels was investigated. Previous reports often used small sets of blood chemistry measures, and results were inconclusive. This experiment examined hearing levels and 27 measures of blood chemistry using various univariate and multivariate statistical procedures. DESIGN: Blood from 89 female and 128 male human subjects was collected. Subjects' ages ranged from 60 to 82 yr, and hearing levels ranged from normal to moderate/severe. Subjects with a history of middle ear disease were excluded. Electrolyte panel (Na, K, Cl, CO2, Ca, urea nitrogen, glucose, creatinine, and Mg), hematology panel (WBC, RBC, Hgb, hematocrit, platelet, etc.), serum lipids (total cholesterol, low-density lipoprotein [LDL], and high-density lipoprotein [HDL]), immunoglobulins (IgG, IgA, IgM, and IgE), and thyroxine were analyzed using univariate and multivariate statistical procedures. RESULTS: Blood chemistry levels of most subjects were within normal ranges as defined by our laboratory. Correlation between blood chemistry measures and pure-tone averages (PTAs) ranged from minimal to low. Results of factor analysis, discriminant analysis, and canonical analysis showed that combining blood chemistry measures from the same panel still could not predict PTA effectively. One exception to this was a gender-specific effect of cholesterol. Hearing levels of women with high LDL/HDL ratios were 5 dB better than those of women with low LDL/HDL ratios. The comparable difference in men was only 1 dB. CONCLUSION: Results suggest that blood chemistry measures that are primarily within the normal range have very little value in predicting pure-tone thresholds in older subjects.

Age Factors↗