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PubMed1993

Family history models of alcoholism: age of onset, consequences and dependence.

The association of a family history of alcoholism to susceptibility to alcoholism has been well documented over the past 3 decades. The classification of a family history of alcoholism commonly involves the division of subjects into family history positive and negative groupings. However, diverse definitions are used to define positive family histories. These diverse definitions of family alcoholism impede the comparison of results from different studies. The present study evaluates several classification schemes and compares them with a new method for the analysis of family patterns of alcoholism (FPA). A sample of 220 male alcoholic veteran inpatients were assessed for age of onset of alcoholism, consequences of drinking and the severity of their dependence. Multiple regression equations were estimated for several dichotomous family history models and each model was evaluated against a comparable FPA model that included the same family members. Comparisons of the classification models with the equivalent FPA analysis model facilitated comparisons of the contribution of each family history designation to changes in amount of explained variance. In all instances, the FPA analyses explained more variance than did the comparable dichotomous family history models. In addition, the FPA analyses reveal the relative explanatory power of each family member and indicate that maternal relatives often have a more important contribution than has been indicated previously.

Adult↗

PubMed2001

Gabapentin for neuropathic pain: systematic review of controlled and uncontrolled literature.

OBJECTIVE: To assess the efficacy/effectiveness and side effects of gabapentin for the treatment of neuropathic pain. DESIGN: Systematic review of the literature. METHODS: Extensive search of several electronic databases located both controlled and uncontrolled studies. Efficacy was assessed through meta-analysis of randomized controlled trials (RCTs), whereas the effectiveness of gabapentin in uncontrolled studies was assessed via a novel system of dichotomous classification of "bad" versus "good" results. FINDINGS: Thirty-five papers involving 727 patients with multiple neuropathic pain conditions met the inclusion criteria. The meta-analysis of the 2 high-quality, placebo-controlled RCTs showed positive effect of gabapentin in diabetic neuropathy and post-herpetic neuralgia. The addition of 2 low-quality, placebo-controlled RCTs did not alter the magnitude or direction of observed effect. The uncontrolled studies demonstrated positive effect on pain in different neuropathic syndromes, as well as benefit on different types of neuropathic pain; highest dose administered and rate-of-dose escalation showed wide variability between prescribers. Fewer and less severe side effects were reported in the uncontrolled studies. CONCLUSIONS: Gabapentin seems to be effective in multiple painful neuropathic conditions. The variable prescribing patterns of the uncontrolled studies raise the suspicion that effectiveness may be reduced if one limits administration of the drug to very low doses, whereas rapid dose escalation may be associated with increased central nervous system side effects. Well-designed controlled trials may provide insight into differential symptom sensitivity to the drug.

Acetates↗

PubMed1985

Risk factors for severe bacterial infections after valve replacement and aortocoronary bypass operations: analysis of 246 cases by logistic regression.

Risk factors for severe bacterial infections, that is, deep sternal wound infection, pneumonia, septicemia, and prosthetic valve endocarditis, were evaluated in 246 consecutive patients undergoing valve replacement (N = 84) or aortocoronary bypass operation (N = 162). Multiple logistic regression analysis was applied to determine the ability of putative risk factors to predict infection. The risk factors considered were age, sex, diabetes mellitus, duration of cardiopulmonary bypass (CPB), duration of operation, amount of blood restored on the day of operation, repeat thoracotomy for bleeding, intraaortic balloon pumping, reoperation, emergency operation, and the professional status of the surgeon. Severe infections occurred in similar frequency after valve replacement (8/84; 9.5%) and aortocoronary bypass (11/162; 6.8%). For patients who had a bypass procedure, repeat thoracotomy was the only factor significantly associated with infection (p = 0.0004). However, the classification analysis revealed that this variable alone is too unspecific for a reliable prediction. Univariate analysis indicated that restoration of more than 2,500 ml of blood (p = 0.0001), reoperation (p = 0.0821), duration of operation (p = 0.0061), duration of CPB (p = 0.0318), and intraaortic balloon pumping (p = 0.0281) were associated with infection following valve replacement. A model with three variables emerged from the multiple logistic regression: after correction for blood restoration, reoperation, and duration of CPB, no other variable was of additional predictive value. For patients who underwent valve replacement, the model performed well in predicting complications. The classification analysis revealed a high correspondence between observed and predicted instances of infection: it correctly predicted 75% of the patients with infection and 96% of those without infection.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1990

Radiographic findings in hereditary multiple exostoses and a new theory of the pathogenesis of exostoses.

Analysis of 330 exostoses in 18 patients affected by hereditary multiple exostoses disease suggested a new classification of exostoses as eccentric or full-thickness. Radiographically arrest of metaphyseal remodeling with failure of coning and persistence of the primary metaphyseal trabeculae was evident in full-thickness exostoses. Similar bone lesions can be obtained experimentally with inhibitors of bone turn-over. A localized, peripheral defect in remodeling over a limited time can give a satisfactory explanation also for the origin of eccentric exostoses. The thesis that this is the basic mechanism of exostosis formation is presented.

Adolescent↗

PubMed2001

Cancellous bone of aged rats maintains its capacity to respond vigorously to the anabolic effects of prostaglandin E2 by modeling-dependent bone gain.

The present study examined the early effects of prostaglandin (PG)E2 on proximal tibial metaphyses of 20-month-old Wistar male rats. PGE, was given to intact rats for 10 and 30 days at 3mg/kg/day. After multiple in vivo fluorochrome labeling, undecalcified longitudinal sections were subjected to analysis of bone histomorphometry and classification of the contour of the cement line in bone formation units. The latter was used to classify bone formation units into modeling, remodeling and uncertain units. After 10 days of treatment, there was a 2% increase in woven bone formation with the appearance of osteoprogenitor cells and increases in the number of osteoblasts (649%) and osteoid (375%) surfaces. Remodeling and modeling units increased by 56% and 429%. respectively. After 30 days of treatment, there was an increase of 212% of total trabecular bone mass, 60% of which was woven bone. In addition, there were increases in labeling surface (147%), mineral apposition rate (760%), bone formation rates tissue area (BFR/T.Ar, 1920%; BFR/B.Pm, 343%), and bone turnover (BFR/B.Ar, 426%). Osteoblasts and osteoid production at 30 days were 29% and 58% less than at 10 days post-treatment. Modeling and remodeling activity did not differ from that seen at 10 days. In addition, PGE2 treatment tended to stimulate the closing of growth plates and decrease the fatty marrow area. We conclude that the aged skeleton was able to respond vigorously to PGE2 treatment. Massive osteoprogenitors cells, and osteoid and osteoblast formations were observed within 10 days. and dramatic woven and lamellar bone formation was seen at 30 days post-treatment. The anabolic effects were driven mainly by modeling.

Aging↗

PubMed2003

Identification of coronaviruses in dogs that segregate separately from the canine coronavirus genotype.

The genetic diversity of 16 canine coronavirus (CCoV) samples is described. Samples were obtained from pups infected naturally living in different areas. Sequence data were obtained from the M gene and pol1a and pol1b regions. The phylogenetic relationships among these sequences and sequences published previously were determined. The canine samples segregated in two separate clusters. Samples of the first cluster were intermingled with reference strains of CCoV genotype and therefore could be assigned to this genotype. The second cluster segregated separately from CCoV and feline coronavirus genotypes and therefore these samples may represent genetic outliers. The reliability of the classification results was confirmed by repeating the phylogenetic analysis with nucleotide and amino acid sequences from multiple genomic regions.

Amino Acid Sequence↗

PubMed2005

A multivariate analysis of otological, surgical and patient-related factors in determining success in myringoplasty.

OBJECTIVES: The aim of this study was to evaluate the effects of smoking and other prognostic factors on long-term surgical outcome and hearing results in myringoplasty. DESIGN: Retrospective cohort. SETTING: Tertiary medical centre. PARTICIPANTS: Eighty myringoplasty operations were analysed retrospectively from the charts of 74 patients who underwent myringoplasty between January 2000 and November 2002 at the First ENT Clinic of Ataturk Training and Research Hospital, using the chi-squared test, Fisher's exact test, t-test and multiple logistic regression statistical analysis. MAIN OUTCOME MEASURES: The effects of prognostic factors and smoking on myringoplasty were investigated by variables noted from patients' files such as smoking status, operation type, duration of dry period of the diseased ear, peroperative otorrhoea, status of the opposite ear, presence of perforation at admission, place of perforation, size of perforation, status of middle ear mucosa, presence of cholesteatoma and tympanosclerosis, ossicular status, previous and related surgery, experience of the surgeon, presence of anterior overhang, presence of valsalva manoeuvre, postoperative antiobiotic cover and income per day. RESULTS: The overall take rate of the myringoplasty graft was 71%. Based on the univariate analysis, smoking status of the patients (P = 0.008), status of the opposite ear (P = 0.01), size of perforation (P = 0.009) and the experience of the surgeon (P = 0.002) were found to be statistically significant (P < 0.01) prognostic factors influencing the success rate of the operations. Multiple logistic regression analysis was subsequently carried out on these prognostic factors and yielded the following classification (95% CI): senior surgeon (OR = 14.3), non-smoking patient (OR = 11.4), longer duration of dry period of the diseased ear (OR = 5.3), normal opposite ear (OR = 5.0) and small perforation (OR = 4.8). CONCLUSIONS: A non-smoking patient, a longer dry ear, a healthy opposite ear, a relatively smaller perforation and a senior surgeon were found to be significant prognostic factors positively influencing the success rate of myringoplasty.

Adolescent↗

PubMed2001

Should newborn mutation scanning for hyperphenylalaninaemia and galactosaemia be implemented? A Polish experience.

OBJECTIVE: To elucidate whether screening for mutations causing hyperphenylalaninaemia (HPA) and classic galactosaemia could provide important, additional information on a clinical phenotype. METHOD: Genotypes that cause disease at the phenylalanine hydroxylase (PAH) gene and galactose-1-phosphate uridyltransferase (GALT) gene in a group of 101 hyperphenylalaninaemic and 77 patients with classic galactosaemia were established. The PAH and GALT mutations were identified in genomic DNA extracted from whole blood leucocytes using single stranded conformational analysis and direct fluorescent sequencing of polymerase chain reaction (PCR) products. RESULTS: Mild HPA and mild phenylketonurea (PKU) were caused by divergent genotypes. In the studied group a total of 26 different mild and intermediate PAH mutations were identified, most of them being rare ones. Classic galactosaemia was caused by two frequent mutations, accounting for 82% of all mutated alleles. CONCLUSIONS: Identification of mild or intermediate mutations causing HPA could provide fast and reliable information about future clinical outcome of a newborn infant. Molecular diagnosis of HPA should be preceded by biochemical analysis and implemented to differentiate mild forms of HPA and cases of ambiguous classification. Because of multiple rare mutations scattered on all exons, scanning of the entire PAH coding sequence could be useful and cost beneficial. Routine genotyping is not proposed in classic phenylketonuria and classic galactosaemia, as it provides limited additional, prospective information on the clinical phenotype.

Adolescent↗

PubMed2006

[Applying matching matrix, factor analysis and clustering analysis to investigation of characteristics of syndromes of phlegm and blood stasis in patients with coronary heart disease].

OBJECTIVE: To investigate the characteristics of syndromes of phlegm and blood stasis in patients with coronary heart disease by multiple statistical methods of matching matrix, factor analysis and clustering analysis, and to provide some references for classification and normalization of diagnosis of syndromes of phlegm and blood stasis of coronary heart disease. METHODS: The correlations among 46 kinds of symptoms in syndrome of non-phlegm and non-blood stasis, syndrome of blood stasis, syndrome of phlegm and syndrome of phlegm-blood stasis blocking in 200 patients with coronary heart disease were analyzed by matching matrix, factor analysis and clustering analysis. RESULTS: The manifestations of tongue and pulse in syndromes of phlegm and blood stasis were significantly different from those in syndrome of non-phlegm and non-blood stasis. The pathogenesis of viscera in syndromes of phlegm and blood stasis lied in the heart and kidney, and the syndrome of deficiency of heart qi was the most common one while the syndrome of deficiency of kidney qi took the secondary place. The syndrome of phlegm was often accompanied by syndrome of deficiency of spleen qi. Only 15 ones of 46 clinical symptoms showed high frequency in concomitant appearance in syndrome of blood stasis, syndrome of phlegm and syndrome of phlegm-blood stasis blocking. Apart from having the common symptoms in syndrome of deficiency in origin, the syndrome of phlegm especially showed white and greasy fur and slippery pulse as well as distention and fullness of chest and abdominal distension; the syndrome of blood stasis showed purplish tongue and ecchymosis on tongue as well as fixed pain; and the syndrome of phlegm-blood stasis blocking showed the main symptoms of both syndrome of phlegm and syndrome of blood stasis. CONCLUSION: The statistical methods of matching matrix, factor analysis and clustering analysis are convenient, and can definitely indicate the clinical characteristics and syndrome differentiation of viscera of different syndromes of phlegm and blood stasis, which are beneficial to further research of diagnosis and differentiation of such syndromes of coronary heart disease.

Cluster Analysis↗

PubMed1987

[Value of ultrasonic diagnosis in the study of metastatic cervical adenopathies. Clinical and anatomo-pathological correlation apropos of 266 lymph node excisions].

Preoperative ultrasound exploration of the cervical node regions was performed for 207 patients; US findings were compared with data obtained by physical examination and histopathologic analysis. Ultrasonography offers multiple advantages: detection of subclinical lymph nodes, accurate measurement of node volume, facilitating classification, evaluation of vascular relations, and particularly diagnosis of internal jugular vein thrombosis. Despite the limitations of ultrasonography, the rapidity and noninvasiveness of this technique make it the procedure of choice for the initial workup of patients with a cervicofacial epithelioma.

Evaluation Studies as Topic↗

PubMed1995

Discriminant classification of motor unit potentials (MUPs) successfully separates neurogenic and myopathic conditions. A comparison of multi- and univariate diagnostical algorithms for MUP analysis.

Multivariate statistical methods may be more appropriate for the multidimensional material of quantitative motor unit potential (MUP) analysis than the multiple univariate tests of the conventional Buchthal analysis. Buchthal analysis was slightly modified before it was used as the gold standard for new multivariate diagnostical algorithms, based on principal component analysis and on MUP discriminant classification: muscle means of continuous variables were related to tolerance limits after adequate transformation. Chi-square tests were used for dichotomized variables, e.g., polyphasia. Sensitivity and specificity of the uni- and multivariate algorithms were compared for 539 muscles from patients with motor neuron diseases, neuropathies and myopathies and for 91 biceps brachii, rectus femoris and tibialis anterior control muscles. False positive results accumulated less than expected by repeat univariate tests for single MUP parameters, due to high correlation. Combination of single parameters to factor scores did not improve specificity. One advantage of factor analysis was that factor matrix and factor scores matched those of previous studies in spite of different input parameters, which may facilitate multicenter comparisons. Discriminant classification successfully separated neurogenic and myopathic conditions, even in myositic muscles and motor neuron diseases, where myopathic and neuropathic MUPs frequently intermingle. Discriminant classification may support expert decisions and add weight to EMG differential diagnosis.

Adult↗

PubMed2006

Regional cerebral glucose metabolic abnormalities in bipolar II depression.

BACKGROUND: Functional neuroimaging studies of bipolar disorder (BD) performed in conjunction with antidepressant treatment trials generally require that patients remain on mood stabilizers to reduce the risk of inducing mania; yet, it is unknown whether the metabolic abnormalities evident in unmedicated BD depressives remain detectable in patients receiving mood stabilizers. This study investigated whether cerebral metabolic abnormalities previously reported in unmedicated BD subjects are evident in depressed bipolar disorder type II (BD II) subjects receiving lithium or divalproex. METHODS: Using [18F]-fluorodeoxyglucose-positron-emission tomography, cerebral glucose metabolism was compared between 13 depressed BD II subjects on therapeutic doses of lithium or divalproex and 18 healthy control subjects. Regional metabolism was compared between groups in predefined regions of interest. RESULTS: Metabolism was increased in the bilateral amygdala, accumbens area, and anteroventral putamen, left orbitofrontal cortex and right pregenual anterior cingulate cortex in depressives versus control subjects. Post hoc exploratory analysis additionally revealed increased metabolism in left parahippocampal, posterior cingulate, and right anterior insular cortices in depressives versus control subjects. Correlational analyses showed multiple limbic-cortical-striatal interactions in the BD sample not evident in the control sample, permitting sensitive and specific classification of subjects by discriminant analysis. CONCLUSIONS: These results confirm previous reports that bipolar depression is associated with abnormally increased metabolism in the amygdala, ventral striatum, orbitofrontal cortex, anterior cingulate, and anterior insula, and extend these results to bipolar disorder type II depressives on lithium or divalproex. They also implicate an extended functional anatomical network known to modulate visceromotor function in the pathophysiology of BD II depression.

Amygdala↗

PubMed1999

DNA polymerase beta-like nucleotidyltransferase superfamily: identification of three new families, classification and evolutionary history.

A detailed analysis of the polbeta superfamily of nucleotidyltransferases was performed using computer methods for iterative database search, multiple alignment, motif analysis and structural modeling. Three previously uncharacterized families of predicted nucleotidyltransferases are described. One of these new families includes small proteins found in all archaea and some bacteria that appear to consist of the minimal nucleotidyltransferase domain and may resemble the ancestral state of this superfamily. Another new family that is specifically related to eukaryotic polyA polymerases is typified by yeast Trf4p and Trf5p proteins that are involved in chromatin remodeling. The TRF family is represented by multiple members in all eukaryotes and may be involved in yet unknown nucleotide polymerization reactions required for maintenance of chromatin structure. Another new family of bacterial and archaeal nucleotidyltransferases is predicted to function in signal transduction since, in addition to the nucleotidyltransferase domain, these proteins contain ligand-binding domains. It is further shown that the catalytic domain of gamma proteobacterial adenylyl cyclases is homologous to the polbeta superfamily nucleotidyltransferases which emphasizes the general trend for the origin of signal-transducing enzymes from those involved in replication, repair and RNA processing. Classification of the polbeta superfamily into distinct families and examination of their phyletic distribution suggests that the evolution of this type of nucleotidyltransferases may have included bursts of rapid divergence linked to the emergence of new functions as well as a number of horizontal gene transfer events.

Adenylyl Cyclases↗

PubMed1982

Analysis of criteria in staging in multiple myeloma.

One hundred and thirty patients suffering from multiple myeloma were reviewed for retrospective study of their classification according to Durie and Salmon's staging system. No significant difference was found in survival between patients in stage I, II and III. Since then, each criterion developed by Durie and Salmon was evaluated separately. Only the Hb level showed a significant influence; a Hb level under 8.5 g/dl or corrected calcaemia above 3 mmol/l were never found separately. When survival according to the number of criteria was considered there was no difference. These findings agree with the well-founded classification of Durie and Salmon but the real importance of each criteria is questionable.

Calcium↗

PubMed2006

Classification of epilepsy types through global network analysis of scalp electroencephalograms.

Epilepsy is a dynamic disease in which self-organization and emergent structures occur dynamically at multiple levels of neuronal integration. Therefore, the transient relationship within multichannel electroencephalograms (EEGs) is crucial for understanding epileptic processes. In this paper, we show that the global relationship within multichannel EEGs provides us with more useful information in classifying two different epilepsy types than pairwise relationships such as cross correlation. To demonstrate this, we determine the global network structure within channels of the scalp EEG based on the minimum spanning tree method. The topological dissimilarity of the network structures from different types of temporal lobe epilepsy is described in the form of the divergence rate and is computed for 11 patients with left (LTLE) and right temporal lobe epilepsy (RTLE). We find that patients with LTLE and RTLE exhibit different large scale network structures, which emerge at the epoch immediately before the seizure onset, not in the preceding epochs. Our results suggest that patients with the two different epilepsy types display distinct large scale dynamical networks with characteristic epileptic network structures.

Artificial Intelligence↗

PubMed2006

Gender differences in self-rated and partner-rated multiple intelligences: a Portuguese replication.

The authors examined gender differences and the influence of intelligence quotient (IQ) test experience in the self and partner estimation of H. Gardner's (1999) 10 multiple intelligences. Portuguese students (N = 190) completed a brief questionnaire developed on the basis of an instrument used in previous research (A. Furnham, 2001). Three of the 10 self-estimates yielded significant gender differences. Men believed they were more intelligent than were women on mathematical (logical), spatial, and naturalistic intelligence. Those who had previously completed an IQ test gave higher self-estimates on 2 of the 10 estimates. Factor analysis of the 10 and then 8 self-estimated scores did not confirm Gardner's 3-factor classification of multiple intelligences in this sample.

Adult↗

PubMed2003

Applications of image analysis to anatomic pathology: realities and promises.

Image Analysis in Pathology is viewed as an ancillary method meant to provide objective support in the resolution of difficult problems. Its Achilles heel is the process of nuclear segmentation (delimitation of the nuclear membrane) which is extremely difficult in pathology materials. Although interactive segmentation procedures are available no reliable fully automatic method has been described. The only application of image analysis that has truly succeeded in Pathology is DNA ploidy measurement. A very desirable application is the quantitation of immunohistochemical markers, which is technically challenging, has been resolved only in certain cases and is unlikely to have a general solution. Nuclear quantitation has repeatedly proven to be helpful in reaching differential diagnoses, in particular when based on size distributions of nuclear profiles rather than its average, but is hampered by the segmentation problem discussed above. Texture analysis of chromatin is an exciting, mathematically complex application likely to succeed, for which many approaches have been described. Finally a diagnosis (classification) can be obtained based on algorithms applied to multiple descriptors of tumor cells (for instance nuclear sizes, chromatin texture, shape, etc). The best classificatory approaches are neural networks (a form of artificial intelligencee), multivariate analysis, and logistic regression (statistical).

Algorithms↗

PubMed2005

A theoretical and experimental analysis of linear combiners for multiple classifier systems.

In this paper, a theoretical and experimental analysis of linear combiners for multiple classifier systems is presented. Although linear combiners are the most frequently used combining rules, many important issues related to their operation for pattern classification tasks lack a theoretical basis. After a critical review of the framework developed in works by Tumer and Ghosh on which our analysis is based, we focus on the simplest and most widely used implementation of linear combiners, which consists of assigning a nonnegative weight to each individual classifier. Moreover, we consider the ideal performance of this combining rule, i.e., that achievable when the optimal values of the weights are used. We do not consider the problem of weights estimation, which has been addressed in the literature. Our theoretical analysis shows how the performance of linear combiners, in terms of misclassification probability, depends on the performance of individual classifiers, and on the correlation between their outputs. In particular, we evaluate the ideal performance improvement that can be achieved using the weighted average over the simple average combining rule and investigate in what way it depends on the individual classifiers. Experimental results on real data sets show that the behavior of linear combiners agrees with the predictions of our analytical model. Finally, we discuss the contribution to the state of the art and the practical relevance of our theoretical and experimental analysis of linear combiners for multiple classifier systems.

Algorithms↗