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PubMed2004

Cross-sectional analysis of different variables of patients with non-insulin dependent diabetes and their periodontal status.

The periodontal condition of 72 non-insulin dependent diabetes patients was compared with that of 92 nondiabetic individuals. Plaque Index (PII), Calculus Index (CI), Gingival Index (GI), and attachment loss (AL) were measured on four surfaces of six teeth in each subject. All four parameters were significantly higher in the diabetic group. No significant difference in the frequency of toothbrushing was found between the groups. For all age groups, GI and AL were higher in the diabetic group. In each group, GI was not changed with age, while AL increased with age. Classification of the groups based on PII showed that the diabetic group's GI was higher than the nondiabetic group for low, medium, or high PII values. The diabetic group showed higher AL for only the medium and high PII groups. Classification by CI revealed that the diabetic group's GI and AL were significantly higher than those of the nondiabetic group for subjects with low, medium, or high values of CI. Multiple regression analysis revealed that the main factor affecting GI was the presence or absence of diabetes. PII and CI both showed a significant relationship with GI; age was the second most significant factor. The most significant factors influencing AL were CI and the presence or absence of diabetes; age was the second most significant factor. Patients who had had diabetes for more than 10 years had a higher AL than those who had suffered from diabetes for less than 10 years. Patients with average HbA1c values > or = 10% had more serious mean GI values than those with HbA1c values < 10%. In patients with diabetes, age, plaque accumulation, and calculus formation have more detrimental effects on the periodontal apparatus than in healthy individuals.

Age Factors↗
PubMed2002

Classification of the caspase-hemoglobinase fold: detection of new families and implications for the origin of the eukaryotic separins.

A comprehensive sequence and structural comparative analysis of the caspase-hemoglobinase protein fold resulted in the delineation of the minimal structural core of the protease domain and the identification of numerous, previously undetected members, including a new protease family typified by the HetF protein from the cyanobacterium Nostoc. The first bacterial homologs of legumains and hemoglobinases were also identified. Most proteins containing this fold are known or predicted to be active proteases, but multiple, independent inactivations were noticed in nearly all lineages. Together with the tendency of caspase-related proteases to form intramolecular or intermolecular dimers, this suggests a widespread regulatory role for the inactive forms. A classification of the caspase-hemoglobinase fold was developed to reflect the inferred evolutionary relationships between the constituent protein families. Proteins containing this domain were so far detected almost exclusively in bacteria and eukaryotes. This analysis indicates that caspase-hemoglobinase-fold proteases and their inactivated derivatives are widespread in diverse bacteria, particularly those with a complex development, such as Streptomyces, Anabaena, Mesorhizobium, and Myxococcus. The eukaryotic separin family was shown to be most closely related to the mainly prokaryotic HetF family. The phyletic patterns and evolutionary relationships between these proteins suggest that they probably were acquired by eukaryotes from bacteria during the primary, promitochondrial endosymbiosis. A similar scenario, supported by phylogenetic analysis, seems to apply to metacaspases and paracaspases, with the latter, perhaps, being acquired in an independent horizontal transfer to the eukaryotes. The acquisition of the caspase-hemoglobinase-fold domains by eukaryotes might have been critical in the evolution of important eukaryotic processes, such as mitosis and programmed cell death.

Amino Acid Sequence↗
PubMed2006

Classification of antipsychotic drugs by gene expression in the frontal cortex of mice.

Antipsychotic drugs are classified as typical and atypical based on extrapyramidal effects. However, since the frontal cortex is one of the most important regions for antipsychotic actions, this study attempted to classify antipsychotic drugs based on gene expression in the frontal cortex. Chlorpromazine and thioridazine were selected as typical antipsychotics, and olanzapine and quetiapine as atypical antipsychotics. Since these drugs have similar chemical structures, the effect of the basic structure on gene expression can be eliminated. Cluster analysis of microarray experiments separated 4-drug-administered mice into chlorpromazine-quetiapine and thioridazine-olanzapine groups. This classification scheme is different from that which is based on criteria currently used to group the typical and atypical drugs and suggests that antipsychotic drugs can be further separated into multiple groups.

Animals↗
PubMed1995

Ovarian dysplasia in epithelial inclusion cysts. A morphometric approach using neural networks.

BACKGROUND: Ovarian dysplasia has been described in the ovarian surface epithelium by histologic and morphometric studies. This study evaluates ovarian dysplasia in epithelial inclusion cysts adjacent to overt carcinoma and also incidentally found in ovaries removed for nonneoplastic diseases, including oophorectomies for family history of ovarian cancer, using an artificial neural network. METHODS: Histologic sections from 37 ovaries of which 26 were diagnosed with dysplasia in epithelial inclusion cysts (10 adjacent to carcinoma and 16 incidental) and 11 with benign epithelial inclusion cysts were evaluated by tracing nuclear profiles and assessing measures of nuclear area, shape, and texture. These sections were analyzed using artificial neural networks and also statistically using the Kruskal-Wallis test with the Dunn procedure to compare the morphologic similarity of dysplasia found incidentally in inclusion cysts unrelated to carcinoma from that in inclusion cysts adjacent to carcinoma. RESULTS: Neither statistical nor artificial neural network analysis was able to distinguish between incidental and adjacent dysplasia. Both types differed significantly from the control cases. CONCLUSIONS: Neural networks are powerful classification tools when applied to multiple variables extracted from individual cases. In this study, they helped to substantiate the similarity between dysplasia found incidentally and that adjacent to ovarian carcinoma. Because dysplasia represents a potential precancerous lesion, its incidental finding may help identify patients at risk for developing ovarian carcinoma.

Female↗
PubMed2006

Measurement and management of human-induced patterns of forest fragmentation: a case study.

In many tropical developing countries, the twin pressures of population and poverty are resulting in substantial fragmentation of forests, increasing the probability of extinction for many species, Forest fragmentation occurs when large contiguous forests are perforated by small holes or broken up into edges and smaller patches to form a nonforested matrix of open spaces. Thus, forest fragmentation refers not only to the area of forest cleared, but also to the pattern of this clearance, the resulting forest's spatial properties. Both characteristics are important for species survivability. Apart from opening up forests to many abiotic and biotic influences, fragmentation can affect species dispersal and migration through its effects on forest connectivity. Landscape ecology conceptualizes connectivity as a gradient of critical thresholds, ranging from the large intact forest to the small unconnected forest patch. This article reports results from a multiple-scale analysis of forest fragmentation in Jamaica's Cockpit Country, an area of once contiguous forest now under threat from human encroachment. Spatial forest data derived from classification of ETM+ satellite imagery are used to measure fragmentation patterns representing various degrees of forest connectivity and density. The results suggest that, overall, 81% of the region is in forest. However, fragmentation patterns also suggest that this forest is riven with extensive perforations indicative of an early stage in the decline of contiguity. The results provided by the spatial fragmentation model are a first step in the design of effective conservation and rehabilitation plans for the area. The article concludes with a discussion of possible multiscale management options for the region.

Agriculture↗
PubMed1996

Inter-observer reliability in the interpretation of coronary angiograms.

The interpretation of coronary angiograms is indispensable in determining procedure in coronary surgery. The aim of this study was to measure the overall reliability of a group of surgeons in the interpretation of coronary angiograms, surgical procedure and the evaluation of operative risk. Ten coronary angiograms were interpreted by eight cardiac surgeons at four different medical centers. Evaluation of coding discrepancies, in this case of multiple raters applying an ordinal-scale classification scheme (0, 1, 2) with no expert yardstick available for coding, was explored by a two-way random factor analysis of variance. Reliability was substantial for the assessment of stenosis irrespective of the artery (intraclass correlation coefficient (ICC) ranging from 0.92 to 1), and good for the distal part of the artery (ICC ranging from 0.83 to 0.86) as well as for the collateral provision (ICC ranging from 0.75 to 0.94). Agreement between surgeons was good with respect to the number of bypasses to be performed (ICC = 0.88). The number of bypass per patient varied from 2.6 to 3.2 depending on the surgeon. Agreement as to whether or not to bypass was substantial for the right coronary artery (ICC = 0.92), good for the marginal artery (ICC = 0.87) and fair for the left anterior descending artery (ICC = 0.60) and the circumflex artery (ICC = 0.60). There was a higher rate of agreement concerning inferior wall motion (ICC = 0.98) than of the anterior wall motion (ICC = 0.78). Agreement was substantial for ejection fraction (ICC = 0.93), operative risk (ICC = 0.93) and the type of coronary tree (ICC = 0.85). With respect to the overall set of items, no one surgeon disagreed significantly with the rest of the group. Some disagreement regarding anatomy suitable for revascularization exists between surgeons. Surgical assessment of risk is similar. Cardiac surgeons quickly learn to assess risk in a similar manner, even though they might not always graft the same anatomic vessels or assess regional wall motion similarly.

Coronary Angiography↗
PubMed2002

Association of antiretroviral resistance genotypes with response to therapy--comparison of three models.

Genotype-based resistance assays are commonly used to aid treatment in HIV-infected individuals failing antiretroviral therapy. The relationship between genotype and antiretroviral therapy comes mostly from in vitro assays of the response to a single drugs although there is a need for a prediction of clinical response to combination therapy. We have compared three different methods of analysing genotype data as a predictor of clinical response in a small clinical cohort of highly antiretroviral-experienced individuals failing therapy. No method performed well beyond 8 weeks into a new therapeutic regimen. A model based on the number of 'primary' mutations was statistically significant, but a multiple regression model, which identified specific mutations explained threefold more variation in response. Optimal prediction in this dataset was given by a model obtained from a classification tree analysis, in which genotype at amino acid sites 135 and 202 were combined with amino acid site 184, which explained over 50% of the deviance in the data and had a classification success of 86%.

Adult↗
PubMed1998

[Books on anesthesiology and resuscitation published in Spain. An approach to their study].

INTRODUCTION: Few authors have examined the publication of medical books. Our aim was to analyze the nature of books published in Spain on anesthesiology and recovery. MATERIAL AND METHODS: Books listed by the Spanish ISBN agency were selected if they included anestesi* or reanima* in any field. Duplicates were removed. Multiple editions or references were considered single books, with data for the oldest edition entered into analysis. Multiple volume collections were grouped as complete works. Data analyzed for each book were year of publication, language (of publication and the original), subject (according to ISBN classification) and place of publication. Nine subject classifications were applied: general, recovery, anesthetic techniques, pharmacology, obstetrics/gynecology, pediatrics, veterinary anesthesia, dental anesthesia and miscellaneous. RESULTS: We analyzed 216 books. Years that saw publication of the greatest number of books were 1988 (17), 1993 (16) and 1979 (15), and the five-year period in which the most books were published was 1985 to 1989 (48 books, 22.2%). Most books (114, 52.8%) were originally written in English, Spanish being the second most common original language (58, 26.8%). All books were published in Spanish. The Spanish ISBN classification system identified 11 categories: general diseases/clinical medicine/therapy (161, 74.5%); drugs/pharmacology/physical therapy/toxicology (20, 9.3%); gynecology/obstetrics (9, 4.2%), veterinary medicine (9, 4.2%) and medicine (8, 3.7%). Classification by specific subjects showed a predominance of monographs or treatises on general aspects (42, 19.4%) followed by books on recovery (37, 17.1%), anesthetic techniques (25, 11.6%) and pharmacology (17, 7.9%). Most books were published in Barcelona (142, 65.7%), Madrid (36, 16.7%) or Saragossa (10, 4.6%). CONCLUSIONS: Spanish publication of books on anesthesiology and recovery has increased in recent years. Most books are translations usually from English. Spanish ISBN agency data, although it has limitations, can be useful for locating books published in Spain on anesthesiology and recovery. It would be useful to introduce keywords into the ISBN data base so that books on specific subjects could be classified and retrieved.

Anesthesiology↗
PubMedDate not supplied

[Waiting time? Triage. An alternative in emergency department].

OBJECTIVE: To evaluate the impact of a triage system on waiting times and patient satisfaction of one secondary care hospital emergency department (ED). MATERIAL AND METHODS: This was a quasiexperimental study. All patients > 15 years demanding emergency care of the selected hospital were included (n = 1,010); a sample was drawn for applying a satisfaction questionnaire (n = 198). The intervention, in charge of trained nurses, consisted of a classification system based on the national scale of the United Kingdom of five categories. The real waiting time was measured from registration to initiation of care. The analysis included descriptive statistics, the sign test and multiple logistic regression analysis. RESULTS: Seventy-one percent of the patients attended the ED spontaneously. The first three categories, considered real emergencies, engaged more than half of the patients. Immediate care was received in category 1 similar to the standard (p > 0.05); the real waiting time in the rest of categories was less than the expected standard (p < 0.01). Sixty-three percent was very satisfied with the waiting time from triage to initiation of care and 74%, with overall care of the ED. Satisfaction with nursing care and waiting time from arrival to initiation of medical care were determinants for satisfaction with overall care, independent of sex and age. CONCLUSIONS: The triage system largely challenged the not easy ED demand and its waiting times in addition to patient satisfaction. This simple classification scale allows improvement in managing emergency services and cases, the benefits can be potentially extended to other health care services.

Emergency Service, Hospital↗
PubMed1993

Classification of drug-induced behaviors using a multi-layer feed-forward neural network.

Measurement of laboratory animal motor behavior is an important part of many studies of experimental manipulations of the central nervous system. Current automated data collection and analysis systems are limited in the number of behaviors that can be monitored and quantified simultaneously. This paper describes a signal analysis technique that when used to analyze the data from a modified Stoelting electronic activity monitor is capable of classifying multiple behavior categories automatically. In this technique, the output signal from the motility monitor is fixed-length segmented and feature extraction is performed, calculating the Fourier transform and power spectrum of each data segment. An error back-propagation neural network, implemented on a microcomputer, is used to perform behavior classification of the segment power spectra. The technique provides a high degree of accuracy in automatic behavior classification and should prove useful in the quantitative assessment of behavior.

Animals↗
PubMed2002

Evolution of DNA polymerase families: evidences for multiple gene exchange between cellular and viral proteins.

A phylogenetic analysis of the five major families of DNA polymerase is presented. Viral and plasmid sequences are included in this compilation along with cellular enzymes. The classification by Ito and Braithwaite (Ito and Braithwaite 1991) of the A, B, C, D, and X families has been extended to accommodate the "Y family" of DNA polymerases that are related to the eukaryotic RAD30 and the bacterial UmuC gene products. After analysis, our data suggest that no DNA polymerase family was universally conserved among the three biological domains and no simple evolutionary scenario could explain that observation. Furthermore, viruses and plasmids carry a remarkably diverse set of DNA polymerase genes, suggesting that lateral gene transfer is frequent and includes non-orthologous gene displacements between cells and viruses. The relationships between viral and host genes appear very complex. We propose that the gamma DNA polymerase of the mitochondrion replication apparatus is of phage origin and that this gene replaced the one in the bacterial ancestor. Often there was no obvious relation between the viral and the host DNA polymerase, but an interesting exception concerned the family B enzymes: in which ancient gene exchange can be detected between the viruses and their hosts. Additional evidence for horizontal gene transfers between cells and viruses comes from an analysis of the small damage-inducible DNA polymerases. Taken together, these findings suggest a complex evolutionary history of the DNA replication apparatus that involved significant exchanges between viruses, plasmids, and their hosts.

Animals↗
PubMed1993

Clinical trials in multiple sclerosis: a critical review (1970-1990).

The present study is a critical review of 100 papers concerning clinical trials in Multiple Sclerosis (MS), published between 1970-1990. We analyzed 20 validity criteria (internal 12, and external 8) and codified each item as "adequate" or "not adequate", so that the validity of each report was quantified. In addition, we used a statistical method of automatic classification (cluster analysis) to subdivide all the papers in 4 groups with growing validity. Only 52 reports had a fairly good or good validity, therefore more efforts are suggested to correctly plan clinical trials in MS and lead to reliable results.

Evaluation Studies as Topic↗
PubMed2006

Discriminative analysis of relapsing neuromyelitis optica and relapsing-remitting multiple sclerosis based on two-dimensional histogram from diffusion tensor imaging.

It is difficult to completely differentiate patients with relapsing neuromyelitis optica (RNMO) from relapsing-remitting multiple sclerosis (RRMS) for their similarities in clinical manifestation. In this study, we proposed a novel approach, using two-dimensional histogram of apparent diffusion coefficient (ADC) and fractional anisotropy (FA) of the brain derived from diffusion tensor imaging (DTI) as classification feature, to discriminate patients with RNMO from RRMS. In this approach, two-dimensional principal component analysis (2D-PCA) was used to extract feature and reduce dimensionality of matrix-formed data efficiently. Then linear discriminant analysis (LDA) was performed on these extracted features to find the best projection direction to separate patients with RNMO from RRMS. Finally, a minimum distance classifier was generated on the basis of projection scores. The correct recognition rate of our method reached 85.7%, validated by the leave-one-out method. This result was much higher than that using feature of ADC or FA separately (59.5% for ADC, 76.2% for FA). In conclusion, the proposed method on the basis of combined features is more effective for classification than those merely using the features separately, and it may be helpful in differentiating RNMO from RRMS patients.

Diffusion Magnetic Resonance Imaging↗
PubMed1994

Neural network approach in multichannel auditory event-related potential analysis.

Even though there are presently no clearly defined criteria for the assessment of P300 event-related potential (ERP) abnormality, it is strongly indicated through statistical analysis that such criteria exist for classifying control subjects and patients with diseases resulting in neuropsychological impairment such as multiple sclerosis (MS). We have demonstrated the feasibility of artificial neural network (ANN) methods in classifying ERP waveforms measured at a single channel (Cz) from control subjects and MS patients. In this paper, we report the results of multichannel ERP analysis and a modified network analysis methodology to enhance automation of the classification rule extraction process. The proposed methodology significantly reduces the work of statistical analysis. It also helps to standardize the criteria of P300 ERP assessment and facilitate the computer-aided analysis on neuropsychological functions.

Algorithms↗
PubMed2000

[Clinical characteristics of seafood allergy and classification of 10 seafood allergens by cluster analysis].

The aim of this study was to investigate the clinical characteristics of children who showed sensitization to any type of seafood and to classify the 10 seafood allergens based on IgE reactivities by a cluster analysis. In children with bronchial asthma (BA) and/or atopic dermatitis (AD), we defined the 'seafood' group as 23 patients having any type of seafood specific IgE antibody (CAP system). We analyzed the clinical features, the serum total IgE and each allergen specific IgE level. In addition, ten seafood allergens were also classified by a cluster analysis. Three patients revealed immediate hypersensitivity to some seafood. The frequency of patients with AD and the total IgE in the seafood group were high and the patients in this group were tend to be sensitized to multiple allergens. Seafood allergens were classified into 4 groups, 1) salmon, sardine, horse mackerel and mackerel, 2) cod and tuna, 3) octopus and squid, and 4) crab and shrimp, by a cluster analysis. These findings corresponded to the biological classification and the classification by the reported common allergens among various types of seafood. Based on our findings, this classification is therefore considered to be useful when selecting allergens to screen for sensitization to seafood.

Allergens↗
PubMed2004

Current burden of sudden cardiac death: multiple source surveillance versus retrospective death certificate-based review in a large U.S. community.

OBJECTIVES: We sought to determine the annual incidence of sudden cardiac death (SCD) in the general population using a prospective approach. To assess the validity of retrospective surveillance, a simultaneous comparison was made with a death certificate-based method of determining SCD incidence. BACKGROUND: Accurate surveillance and characterization of SCD in the general population is likely to significantly facilitate current and future community-based preventive and therapeutic interventions. METHODS: We performed a prospective evaluation of SCD among all residents of Multnomah County, Oregon (population 660,486) using multiple sources of surveillance. A comprehensive analysis of circumstances of death, medical records, and available autopsy data was performed. Comparisons were made with a retrospective, death certificate-based determination of SCD incidence using International Classification of Diseases-Version 10 codes and location of death. RESULTS: Between February 1, 2002, and January 31, 2003, 353 residents suffered SCD (incidence 53 of 100,000; median age 69 years, 57% male) accounting for 5.6% of overall mortality. Of these, 75 cases (21%) were identified using sources other than first responders. Resuscitation was attempted in 237 cases (67%) and successful (survival to hospital discharge) in 28 (8%). The retrospective death certificate-based review yielded 1,007 cases (incidence 153 of 100,000; median age 81 years, 51% male), and the positive predictive value of this methodology was 19%. CONCLUSIONS: Sudden cardiac death accounts for 5.6% of annual mortality, and prospective evaluation in the general population appears to be feasible. The use of multiple sources of ascertainment and information significantly enhances phenotyping of SCD cases. Retrospective death certificate-based surveillance results in significant overestimation of SCD incidence.

Adolescent↗
PubMed2005

Reliable classification and recombination analysis of porcine endogenous retroviruses.

Prevention of cross-species infection with porcine endogenous retroviruses (PERV) is crucial for xenotransplantation. Previous studies described the potential risk of infection for the PERV gamma1 subfamilies A, B and C. Replication competent PERV gamma1 proviruses designated to a particular subfamily and hybrid viruses originating from retroviral recombination events between the subfamilies were observed. Future pig genome sequencing projects will reveal multiple novel PERV proviruses from additional breeds and animals. Evaluation of these viral genomes has to be carried out to assess the potential risk of retroviral cross-species infection. In this study, we tested common sequence comparison methods for the classification of PERV sequences and the detection of hybrid clones. The examination of the polymorphic nucleotide positions was found to be the most suitable procedure. We describe a fast and simple method using bioinformatic software tools which can also be applied to analogous analyses of other viral genomes.

Animals↗