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PubMed2007

Predictors of long-term neurological sequelae of tuberculous meningitis: a multivariate analysis.

There is paucity of studies on predictors of long-term sequelae of tuberculous meningitis (TBM). We report the neurological sequelae of TBM at 1 year and their predictors. Patients with TBM who were followed up for 1 year were included. The diagnosis of TBM was based on clinical, cerebrospinal fluid (CSF) and computed tomography (CT) scan findings. Detailed neurological examinations at admission and at 1 year were carried out. All the patients received four-drug antitubercular therapy. The frequency of sequelae at 1 year were noted and the role of various demographic (age, sex, duration of illness, BCG vaccination), clinical (weakness, seizure, extra central nervous system tuberculosis, Glasgow Coma Scale (GCS) score, cranial nerve palsy, stage, corticosteroid, drug-induced hepatitis, shunt surgery), and laboratory findings (erythrocyte sedimentation rate (ESR), CSF cell and protein, CT scan evidences of hydrocephalus, basal exudates, infarctions and tuberculoma) at presentation were evaluated employing logistic regression analysis. Sixty-five patients with TBM were included in this study whose age ranged between 13 and 80 years (mean 33.2), 27 of whom were females. Complete neurological recovery at 1 year occurred in 21.5% patients only although about 50% were independent for activities of daily living. Neurological sequelae were observed in 78.5% patients, which included cognitive impairment in 55%, motor deficit in 40%, optic atrophy in 37% and other cranial nerve palsy in 23%. On logistic regression analysis, focal motor deficit at admission was the most important predictor of neurologic deficits at 1 year. GCS score predicted the cognitive and motor sequelae. Neurological sequelae at year occurred in 78.5% patients with TBM in the form of cognitive impairment, motor deficit and optic atrophy. Sequelae were common in patients who had focal motor deficit and altered sensorium at admission.

Adolescent↗

PubMedDate not supplied

Multivariate analysis of byssinosis risk assessment.

Multiple logistic regression model was used considering byssinosis as an independent variable, and dustiness, smoking, exposure years and age as explanatory variables. Dustiness and length of exposure to the dust were found to be the most important contributory factors to byssinosis prevalence. The risk of byssinosis among workers in card room, blow room and waste plant sections and those who had exposure of more than 5 years was nearly three times than that among workers of other sections of the mill and/or with less than 5 years of exposure.

Byssinosis↗

PubMedDate not supplied

Use of multivariate analysis of MIR spectra to study bread staling.

Different kinds of bread, stored at constant temperature and at controlled humidity conditions for a week since their manufacturing date, were analysed by Attenuated Total Reflectance-Fourier Transform InfraRed (ATR-FTIR) spectroscopy. The collected spectra were processed by Principal Component Analysis (PCA), in order to evaluate the changes occurring during bread ageing. For the sake of comparison, the 1060-950 cm spectral window has been also investigated by curve-fitting methods. It was observed that the first PC increases monotonically with ageing of samples. Furthermore, the more influential variables on PC1 correspond to spectral regions where are located stretching and bending bands, which are mainly attributed to typical starch bonds vibrations.

Bread↗

PubMed1993

Gastric acid secretion and pattern of gastroesophageal reflux in patients with esophagitis and concomitant duodenal ulcer. A multivariate analysis of pathogenetic factors.

This study was designed to assess the relationship between gastric acid output (GAO) and both pattern of gastroesophageal reflux (GER) and severity of esophageal lesions. Gastric acid secretory testing and 24-h intraesophageal pH-monitoring were performed in 31 patients with esophagitis and concomitant duodenal ulcer (E+DU) and compared with those of 72 patients with esophagitis (E). The second aim of this study was to evaluate the role of GAO and other potential pathogenetic factors in the development of esophagitis. The results of the study showed that GAO in patients with E+DU was significantly higher than in patients with E (p < 0.05). There was no significant difference between the two groups of patients with regard to endoscopic findings or GER variables (p < 0.05). Multiple regression analysis with stepwise deletion showed that the presence of hiatal hernia, GER in the upright position and age appear to correlate significantly with the presence of esophagitis. We conclude that no parallel relationship exists between GAO and severity of GER or esophageal lesions in patients with E+DU and that GAO is not a major pathogenetic factor in GER disease.

Adult↗

PubMedDate not supplied

Aortocoronary bypass results: a discriminant multivariate analysis of risk factors of operative mortality.

Clinical results of coronary artery bypass surgery have been evaluated analyzing operative mortality and its related risk factors. Four hundred and thirty seven consecutive patients undergoing coronary artery bypass surgery between January 1979, and December 1983, form the clinical material of this study. The gender of patients was male in 89% of the cases, the age ranged from 34 to 78 years with a mean of 54.8 +/- 8.2 (SD); patients with combined surgical procedures were excluded. The operative mortality was 5.49% (24 patients); no significant difference was found between years of the observation period. Death was due to cardiac causes in 75% of cases. Statistical analysis carried on 14 clinical, angiographic and surgical variables identified as significant risk factors of operative mortality age (p = 0.002) and cross-clamp time (p = 0.016). Both of these increased their weight when entered in a stepwise logistic regression. The EF also showed a value close to statistical significance (p = 0.06).

Adult↗

PubMed1997

A multivariate analysis of the sexual fantasy themes of college men.

Understanding sexual fantasies is important to the scientific study of human sexuality. A sexual fantasy refers to a private or covert experience in which the imagination of desirable sexual activity with a partner is sexually arousing to the individual. Prior sexual experiences of an individual appear to increase the incidence of sexual fantasies, as well as the variety of sexual themes in a fantasy, which permit a greater elaboration of the fantasy theme when compared to less sexually experienced individuals. The present study was an investigation of the factors or sexual themes that emerge in a college male population, as well as a comparison of college men with human samples obtained in other studies: a sample of men and women and a sample of sexually variant men. In this study, 116 male students, all of whom identified themselves as heterosexual, completed the Wilson Sex Fantasy Questionnaire (WSFQ). Results indicated that the present sample had significantly more exploratory, intimate, impersonal, and total sexual fantasies than sexual fantasies reported by female respondents in another study using the WSFQ and significantly more intimate, impersonal, and total sexual fantasizing when compared with a male sample in another study. The men in this study also evidenced less deviant areas of sexual fantasizing when compared with a group of sexually variant men in another study. A principal components analysis extracted four factors, which accounted for 45% of the total variance. The four sexual fantasy topic areas for the most part replicated prior findings by Wilson (1988) but are also more heterogeneous, indicating that male college students engage in a variety of sexual fantasies but seem to favor more intimate, less deviant or exploratory sexual themes that are in line with nonclinical samples and different from several clinical samples of sexually variant men.

Adolescent↗

PubMed2006

Multivariate analysis of microbial communities in the River Elbe (Germany) on different phylogenetic and spatial levels of resolution.

The microbial communities of three different habitat types and from two sediment depths in the River Elbe were investigated by fluorescence in situ hybridization at various levels of complexity. Differences in the microbial community composition of free-flowing river water, water within the hyporheic interstitial and sediment-associated bacteria were quantitatively analyzed using domain- and group-specific oligonucleotide probes. Qualitative data on the presence/absence of specific bacterial taxa were gathered using genus- and species-specific probes. The complete data set was statistically processed by univariate statistical approaches, and two-dimensional ordinations of nonmetric multidimensional scaling. The analysis showed: (1) that the resolution of microbial community structures at microenvironments, habitats and locations can be regulated by targeted application of oligonucleotides on phylogenetic levels ranging from domains to species, and (2) that an extensive qualitative presence/absence analysis of multiparallel hybridization assays enables a fine-scale apportionment of spatial differences in microbial community structures that is robust against apparent limitations of fluorescence in situ hybridization such as false positive hybridization signals or inaccessibility of in situ oligonucleotide probes. A general model for the correlation of the phylogenetic depth of focus and the relative spatial resolution of microbial communities by fluorescence in situ hybridization is presented.

Bacteria↗

PubMed2005

Multivariate analysis of nuclear magnetic resonance data--characterization of critical drug substance quality of gentamicin sulfate.

Fourteen gentamicin sulfate lots collected from international markets showed high quantities of impurities (approximately 30% of studied lots). 1H NMR spectroscopy as a primary analytical method was applied in order to validate the quantification results obtained from micellar electrokinetic chromatography method (MEKC). In this study, 1H NMR data of 46 gentamicin sulfate drug substance lots were used to classify the lots by means of principal component analysis (PCA) of 14 1H NMR-signals in the 5.0-6.0 ppm region. Three main groups could be classified: high purity (3 lots), average quality (28 lots) and low purity (14 lots); one lot proved to be atypical. The 14 normalized signal heights in the 5.0-6.0 ppm region are predictive for purity quality according to a partial least squares (PLS)-model with sum of all impurities as Y-variable (measured by MEKC).

Chromatography, Micellar Electrokinetic Capillary↗

PubMed1997

Multivariate analysis of muscular fatigue during bicycle ergometer exercise.

The purpose of this study is to estimate the endurance threshold in terms of muscular fatigue during bicycle ergometer exercise. The problems to be solved are induced by dynamic movement and the physiological variation of muscle activity: that is, the progression and impairment of muscle activity occur simultaneously. First of all, we used multichannel recordings of myoelectric (ME) signals to reduce the effect by the movement of a bipolar surface electrode relative to the innervation zones. Second, since even the different types of ME parameters contain redundant information on muscular fatigue, we used the principal component analysis (PCA) to represent the meaningful information by small dimensions. Moreover, we proposed a total evaluation pattern to discriminate muscular fatigue from progression of muscle force at a glance. The total evaluation pattern shows the proportion of first principal component, the components of the first eigenvector, and the correlation coefficients as a function of the work load. The assessment using the total evaluation pattern divided eight subjects into three groups, whereas these subjects were not identified by a specific ME parameter.

Adult↗

PubMed1994

Estimation of degree of liver cirrhosis using a fibrosis score; a multivariate analysis of clinical parameters and resected specimens.

We designed this study to estimate the degree of liver cirrhosis using clinical parameters and surgically resected specimens. One hundred and twenty-nine cases who underwent hepatic resection in the Department of Surgery II, Kyushu University Hospital during the period between April 1985 and July 1991 for whom data for all 29 variables evaluated were available, were admitted to this study. On the basis of the histological findings of fibrosis of the liver, the non-neoplastic part of the resected specimens were classified into 3 groups; Z0, no cirrhosis (n = 63), Z1, mild cirrhosis (n = 38), and Z2, severe cirrhosis (n = 28). A univariate analysis revealed 14 significant variables. After multiple logistic regression analysis of these, five independent variables (low platelet count, female, low value of hepaplastin test, a high Pugh's score and a high value of ICG) were identified. We obtained a fibrosis score using the coefficient of each above-mentioned variable. This score increased the discriminative power. The fibrosis score is therefore considered useful for estimating the severity of liver cirrhosis.

Adult↗

PubMed2003

Multivariate analysis and classification of the chemical quality of 7-aminocephalosporanic acid using near-infrared reflectance spectroscopy.

The capability of near-infrared (NIR) spectroscopy in comparison to conventional chemical testing to control the chemical quality of a pharmaceutical intermediate has been investigated. Multivariate projection methods including principal component analysis, partial least-squares discriminant analysis and soft independent modeling of class analogy have been evaluated. 7-Aminocephalosporanic acid has been chosen as an example providing a large variation of quality due to its relative chemical instability. Three sets of production lots have been selected to study the extent of quality information extractable from NIR spectra. The first set of 91 lots covers a very broad range of chemical quality assessed by 8 parameters with a partially extended characterization by physical properties. The general congruence of spectral, chemical, and physical information has been investigated. The second set of 110 lots covers a very narrow range of chemical quality assessed by 11 parameters. With extended quality information, the intrinsic selectivity within the spectral data structure has been studied. The third set of 228 lots characterized by 8 parameters is a selection out of more than 1000 lots over a production period of two years. The ruggedness of the multivariate approach has been confirmed by a cross validation of the classification test.

Algorithms↗

PubMed1998

Multivariate analysis of 9 disease-associated variables for outcome prediction in patients with sepsis.

OBJECTIVE: To assess the ability of 9 clinical or biological variables to predict outcome (survival or nonsurvival) using multiple regression and classification analyses. DESIGN: Prospective, descriptive cohort study with no interventions. SETTING: Surgical intensive care unit of a tertiary care hospital and a medical school research laboratory. PATIENTS: Eighteen patients with a documented source of infection who met currently accepted criteria for sepsis syndrome or septic shock. MAIN OUTCOME MEASURES: Prediction of survival or nonsurvival based on analysis of clinical (Multiple Organ Dysfunction score, Acute Physiology and Chronic Health Evaluation III scores) and biological (plasma levels of cortisol, interleukin 6, interleukin 10, phospholipase A2, soluble tumor necrosis factor receptor p75, and monocyte membrane tumor necrosis factor receptor levels) variables, with comparison of predicted and actual outcomes. RESULTS: Plasma interleukin 6, interleukin 10, and phospholipase A2 concentrations were not significantly (P>.05) different between survivors and nonsurvivors. By standard, forward stepwise, and backward stepwise multiple regression analyses, only monocyte membrane tumor necrosis factor receptor levels measured at the onset of sepsis significantly predicted outcome in all 3 analyses. However, by both standard and backward stepwise analyses, Multiple Organ Dysfunction scores based on evaluation at the onset of sepsis and 24 hours later were also significant predictors of outcome. Classification analysis showed that assignment to outcome group was statistically significant when based on monocyte membrane tumor necrosis factor receptor levels determined at the onset of sepsis or on Multiple Organ Dysfunction scores assessed 24 hours after sepsis was diagnosed. CONCLUSION: Although these findings were based on a relatively small cohort, both multiple regression and classification analyses indicated that only monocyte membrane tumor necrosis factor receptor levels are able to discriminate survivors from nonsurvivors at the onset of sepsis.

Biomarkers↗

PubMed1996

Prognosis of tuberculous meningitis: a multivariate analysis.

Twenty-six clinical, laboratory and CT scan features in 49 patients with tuberculous meningitis (TBM) were analysed to identify the parameters of prognostic significance. Employing univariate analysis, seven variables were found to correlate with three month outcome; these variables included the stage of TBM on admission, focal weakness, Glasgow coma scale (GCS), incontinence, infarction, hydrocephalus and shunt surgery. Analysing all 26 variables, a conditional logistic regression model was derived. In this model stage of TBM, age, focal weakness, cranial nerve palsy and hydrocephalus were found to be contributing to the three month outcome of TBM patients as assessed by the Barthel index.

Adolescent↗

PubMed1997

Resectional surgery of hilar cholangiocarcinoma: a multivariate analysis of prognostic factors.

PURPOSE: To define the prognostic factors after surgical resection of bile duct carcinomas at the hepatic bifurcation. PATIENTS AND METHODS: The retrospective single-center experience details 151 patients after surgical resection of central bile duct carcinoma performed between 1971 and 1995. Tumor removal was accomplished by resection of the bile duct bifurcation either alone (group I, n = 33), in combination with hepatic resection (group II, n = 77), or combined with hepatic and vascular resection (group III, n = 41). Survival analysis was performed by the Kaplan-Meier method and the relationship between each of the clinicopathologic variables and survival was assessed by the log-rank test. Multivariate results were confirmed using Cox regression. RESULTS: The overall hospital mortality rate was 9.9% and depended on the extent of resection (group 1, 6.1%; group II, 7.8%; group III, 17.1%). After exclusion of hospital deaths, the overall patient survival rate was 28.4% at 5 and 15.5% at 10 years, with a median survival duration of 2.05 +/- 0.23 years. Univariate survival analysis identified tumor size, lymph node metastases, residual tumor stage, and tumor grading as factors with a statistically significant prognostic impact. Survival prognosis was not influenced by the site of the tumor according to the classification of Bismuth and Corlette, extent of resection, International Union Against Cancer (UICC) stage, perineural and vascular invasion, age, or sex. In a multivariate Cox analysis, only lymph node metastases and residual tumor stage proved to be of independent prognostic significance. CONCLUSION: Resection of central bile duct carcinoma is feasible in many patients and a favorable outcome after resection is mainly determined by curative resection and the absence of lymph node metastases.

Adult↗

PubMedDate not supplied

Predictive factors of fetal urethral obstruction: a multivariate analysis.

OBJECTIVE: The purpose of this study was to identify predictive factors of fetal urethral obstruction. METHODS: One hundred and forty-eight children with fetal hydronephrosis were admitted, submitted to a systematic protocol and prospectively followed. Possible predictive factors of urethral obstruction associated with fetal echography and clinical findings on admission were studied. The analysis was conducted in two steps. In a univariate analysis, variables associated with urethral obstruction were identified by the chi(2) test or by Fisher's exact test. Then, the variables that were significantly associated with urethral obstruction were included in a multiple logistic regression analysis. RESULTS: After final adjustment by multiple logistic regression analysis, only two variables were identified as independent predictors of fetal urethral obstruction: oligohydramnios (odds ratio, OR = 5, 95% confidence interval, CI, = 1.3-15, p = 0.01) and megacystis (OR = 9, 95% CI = 2.0-40, p = 0.004). The sensitivity and specificity of the combination of both variables were 60 and 98.5%, respectively. CONCLUSIONS: The presence of oligohydramnios and megacystis on prenatal ultrasound is highly predictive of fetal urethral obstruction.

Female↗

PubMed1992

Variation in hepatic estrogen receptor concentrations in patients with liver disease. A multivariate analysis.

Hepatic estrogen receptor concentrations were measured in liver biopsy specimens from 102 patients (58 women and 44 men) with liver disease and correlated to several clinical, biochemical, and histologic background variables by means of multiple regression analysis. Half of the tissue was processed for histologic evaluation with a semiquantitative registration of histologic characteristics, whereas the other part was used for receptor analysis by enzyme immunoassay. Fifteen patients with no or minimal histologic changes served as controls. The analysis shows that the reduced estrogen receptor concentrations observed in patients with chronic liver diseases reflect the degree of liver dysfunction and not the specific type of liver disease. Serum albumin, log serum bilirubin, log serum alkaline phosphatases, and the degree of parenchymal fibrosis were significantly related to hepatic estrogen receptor level in the final regression model, but only part of the variation can be explained by these variables, and other factors must be of importance.

Adult↗

PubMed1998

Natural resistance to intracellular parasites: a study by two-dimensional gel electrophoresis coupled with multivariate analysis.

Natural resistance to Mycobacterium bovis bacillus Calmette-Guérin (BCG) is determined by the Bcg gene (Nramp1), which is exclusively expressed by mature macrophages. The Nramp1 gene is a dominant autosomal gene that has two allelic forms; r confers resistance and s confers susceptibility to infection with intracellular pathogen. Although the wide range of pleiotropic immunological effects of the Nramp1 gene has been described, the exact mechanism of its action remains elusive. In this study we searched for differentially expressed proteins that might provide clues in the studies on Nramp1 gene function. We performed two-dimensional gel electrophoresis of cellular proteins prepared from a B10R macrophage line derived from mice carrying the r allele of the Nramp1 gene, B10S macrophages carrying the s allele, and B10R-Rb macrophages transfected with Nramp1-ribozyme. The classification of protein patterns and selection of distinct proteins characteristic of r or s allele-carrying macrophages was performed using the principal component analysis. We found differential expression of four proteins with the following isoelectric point/molecular weight (pI/Mr) in B10R macrophages compared to B10S and B10R-Rb macrophages: 6.6/25, 7.0/22, 9.1/31.5, and 5.3/8.5. The protein 7.0/22 has been identified as Mn-superoxide dismutase and the best candidate for protein p6.6/25 seems to be Bcl-2 according to the immunoblot analysis. When the splenic macrophages carrying the r or s allele were analyzed, the changes in relative abundance for proteins 6.6/25 and p7.0/22 were satisfactorily reproduced. Overall, the two identified proteins are important in the regulation of intracellular redox balance and the regulation of apoptosis in macrophages, respectively. Our findings may suggest their possible biological role in the innate immunity against intracellular pathogens.

Animals↗

PubMed2005

Interactions of anionic dyes with silica-aminopropyl 1. A quantitative multivariate analysis of equilibrium adsorption and adsorption Gibbs free energies.

In this work silica-aminopropyl (Sil-NH2) was synthesized and employed to evaluate the quantitative roles of temperature, pH, dye concentration, and Hg(II) or anionic surfactant SDB interferents in the adsorptions of blue and red remazol dyes in aqueous medium using four distinct 2(4) factorial designs. The results were analyzed statistically using multiple regressions, Student's t-test, analysis of variance, and F-test. Polynomial modelings were used to define the most important factors affecting dye adsorption. The results indicate that the principal effects of dye concentration and pH, as well as most of the interactions of all factors, are statistically very important in relation to the equilibrium adsorption quantities. However, the adsorption Gibbs free energies are influenced, in general, only by pH, dye concentration, and some binary interactions. Temperature changes do not affect the deltaG values significantly.

Adsorption↗