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PubMed2006

Staged management and outcome of combined pelvic and liver trauma. An international experience of the deadly duo.

Pelvic fracture associated with liver trauma is not an uncommon injury combination in multiple trauma and is associated with high morbidity and mortality. The aim of this study was to examine the characteristics of this specific patient group, to describe the diagnostic and treatment protocols and finally to analyse risk factors associated with mortality. Data were collected over a 6-year period, ending in 2001. The pelvic injury was graded according to the Tile classification system and the hepatic injury was scored using the organ injury scale (OIS). Treatment protocol, associated injuries, complications, length of ICU/Hospital stay and mortality were recorded and analysed. A total of 140 patients (40% female) with a mean age of 35.1+/-15.9 years and a median ISS of 41 were included in this study. The overall mortality rate was 40.7%. Binomial logistic regression analysis revealed age, initial blood pressure, transfusion requirement as well as the severity of head, chest, spleen and liver injury as independent parameters predicting reduced survival rates. This deadly duo of injuries presents a challenge to the trauma surgeon. Rapid assessment and treatment is required to prevent death by haemorrhage. The presence of concomitant injuries renders the patient very sensitive to ongoing or additional physiological disturbance. The principles of 'damage control surgery' must be applied to avoid complications such as acute respiratory distress syndrome (ARDS) and multiple organ dysfunction syndrome (MODS).

Adolescent↗

PubMed1983

T-cell prolymphocytic leukemia. Clinical and immunologic characterization.

The clinical course of a patient with extensive skin involvement due to T-cell prolymphocytic leukemia is described. The malignant cells isolated from the patient's blood and skin were studied utilizing cytochemical analysis and multiple monoclonal antibodies directed against cell surface antigens. The leukemic cells displayed a surface antigen phenotype similar to that of normal post thymic suppressor T-cells. On the basis of this study together with the few published reports, it appears that T-prolymphocytic leukemia is derived from lymphocytes demonstrating either the suppressor or helper phenotype, and that extensive dermal infiltration may be independent of phenotypic classification. Although T-prolymphocytic leukemia shares certain morphologic, cytochemical, and immunologic features with chronic lymphocytic leukemia, it is an aggressive disease with an average survival of approximately 6 months and is best thought of as a distinct pathologic entity.

Antibodies, Monoclonal↗

PubMed2002

Variety identification of wheat using mass spectrometry with neural networks and the influence of mass spectra processing prior to neural network analysis.

The performance of matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry with neural networks in wheat variety classification is further evaluated.1 Two principal issues were studied: (a) the number of varieties that could be classified correctly; and (b) various means of pre-processing mass spectrometric data. The number of wheat varieties tested was increased from 10 to 30. The main pre-processing method investigated was based on Gaussian smoothing of the spectra, but other methods based on normalisation procedures and multiplicative scatter correction of data were also used. With the final method, it was possible to classify 30 wheat varieties with 87% correctly classified mass spectra and a correlation coefficient of 0.90.

Journal Article↗

PubMed1986

The familial sporadic classification: its power for the resolution of genetic and environmental etiologic factors.

An increasingly popular research method for identifying etiologic heterogeneity in psychiatric illness has been to compare the frequency of a risk factor in affected individuals with no affected relatives (sporadic cases) and in affected individuals with one or more affected relatives (familial cases). This paper presents a power analysis of this familial vs sporadic method, assuming a multifactorial model with a normally distributed liability to illness resulting from the additive effect of polygenes and multiple environmental factors. Various parameter estimates for a risk factor that identifies a component of either the genetic or the environmental contribution to disease liability are examined. Almost without exception, large sample sizes of probands and relatives need to be studied to have a substantial probability of detecting etiologic heterogeneity. The required sample size decreases dramatically when monozygotic twins are studied. If the multifactorial model accurately depicts the etiology for psychiatric disorders, these results suggest that the familial versus sporadic design is useful only when pursued in the context of large sample nuclear family studies or studies of monozygotic twins.

Diseases in Twins↗

PubMed1999

Setting bioequivalence requirements for drug development based on preclinical data: optimizing oral drug delivery systems.

The recently proposed Biopharmaceutics Classification System can be used to classify drugs and set standards for scale-up and post-approval changes as well as standards for in vitro/in vivo correlation for immediate and controlled release products. This classification scheme is based on determining the underlying process that is controlling the drug absorption rate and extent, namely, drug solubility and intestinal membrane permeability. Theoretical analysis and experimental results suggest that a permeability/solubility classification scheme can be used to set more rationale drug standards. In particular, high solubility/high permeability, rapidly dissolving drugs may be regulated on the basis of a single point rapid dissolution test while low solubility dissolution rate limited drugs can be regulated based on an in vitro dissolution test that reflects the in vivo dissolution process. This dissolution test may include multiple time points, media change, as well as surfactants in order to reflect the in vivo dissolution process and would be used by the manufacturer for requesting a waiver from a bioequivalence (BE) trial. For controlled release products, the regulation of bioequivalence standards is more complex due to the potential differences in position-dependent permeability/solubility and metabolism of drugs along the gastrointestinal tract. These differences may result in drug absorption rates that are highly transit time dependent. This paper will present the current status of the biopharmaceutic drug classification scheme, the underlying developed data base and its application to optimizing IR and CR products.

Administration, Oral↗

PubMed2000

Dual energy X-ray absorptiometry reference data for Greek population. The impact on diagnosis of using various normal ranges for comparison.

INTRODUCTION: The interpretation of bone mineral density (BMD) measurements and the individual classification of a patient is based on a normal reference range. Unfortunately, not all the manufacturers include in their analysis-software reference values specific for each population. METHODS AND PATIENTS: In our study, using Lunar's DPX-L densitometer, we measured BMD of the lumbar spine and the femur of 4400 healthy women aged (25-80) years and we calculated the corresponding T- and Z-scores. Multiple regression analysis was applied to examine the dependence of BMD on age and weight. Greek data was compared with American and Italian. RESULTS: There was a statistically significant difference between Greek and American mean values of all age groups. The Italian normal range is closer to our data and can be reliably used at least as T-scores are concerned. Still, there is a small discrepancy in Z-scores, which might influence patient management. CONCLUSION: We conclude that Greek reference range should be used for the assessment of osteoporosis of Greek population for better evaluation of bone status and appropriate treatment.

Absorptiometry, Photon↗

PubMedDate not supplied

Fracture dislocations of the tarsometatarsal joints: Analysis of interrater reliability in using the modified Hardcastle classification system.

Fracture dislocations/subluxations of the tarsometatarsal joint are complex injuries that are often misdiagnosed. Prompt recognition and treatment of Lisfranc injuries decrease the likelihood of long-term sequelae. The original (1909) classification system was modified in 1982 and again in 1986. The 1986 classification system, developed by Hardcastle et al, is used most widely in clinical practice and is cited most often in the biomedical literature. For this-or any-classification system to be beneficial, however, multiple observers must be able to use it in a consistent manner, and a high level of interrater agreement should exist. This study examined interrater reliability among clinicians using the modified Hardcastle classification system for Lisfranc fracture dislocations. Thirteen Lisfranc injury radiographs were evaluated by 21 independent observers consisting of surgeons and residents (podiatric and orthopedic) as well as musculoskeletal radiologists, who classified radiographs according to the modified Hardcastle classification system. We used kappa statistics to evaluate the degree of interrater reliability for the entire group. A mean weighted kappa value of 0.54 was found for the group. Moderate interrater agreement was observed among clinicians interpreting the modified Hardcastle classification system for Lisfranc fracture dislocations.

Fractures, Bone↗

PubMed2004

Evaluating methods for classifying expression data.

An attractive application of expression technologies is to predict drug efficacy or safety using expression data of biomarkers. To evaluate the performance of various classification methods for building predictive models, we applied these methods on six expression datasets. These datasets were from studies using microarray technologies and had either two or more classes. From each of the original datasets, two subsets were generated to simulate two scenarios in biomarker applications. First, a 50-gene subset was used to simulate a candidate gene approach when it might not be practical to measure a large number of genes/biomarkers. Next, a 2000-gene subset was used to simulate a whole genome approach. We evaluated the relative performance of several classification methods by using leave-one-out cross-validation and bootstrap cross-validation. Although all methods perform well in both subsets for a relative easy dataset with two classes, differences in performance do exist among methods for other datasets. Overall, partial least squares discriminant analysis (PLS-DA) and support vector machines (SVM) outperform all other methods. We suggest a practical approach to take advantage of multiple methods in biomarker applications.

Algorithms↗

PubMed2025

Discovery of diverse anellovirus sequences in Thai human sequencing data.

UNLABELLED: Anelloviruses are part of the normal human viral flora. Although their diversity in humans has been investigated in many countries, and despite their initial detection in Thailand in 1999, knowledge of Thai anelloviruses remains very limited. This study analyzed 1,175 whole-genome sequencing data sets from Thai individuals to mine for potential anellovirus sequences. Our analyses detected anellovirus sequences in 149 data sets (12.68%), uncovering 434 partial anellovirus sequences and 77 complete genome sequences, characterized by the presence of terminal redundancy, complete orf1, and the conserved untranslated region upstream of the orf1 gene. Sequence analyses indicated that these viruses belong to seven genera, including Alphatorquevirus, Betatorquevirus, Gammatorquevirus, Hetorquevirus, Lamedtorquevirus, Samektorquevirus, and Yodtorquevirus. Notably, Hetorquevirus, Lamedtorquevirus, Samektorquevirus, and Yodtorquevirus had not previously been reported in Thailand. Phylogenetic analysis of ORF1 protein sequences showed that Thai anelloviruses form multiple phylogenetic clusters with non-Thai anelloviruses, indicating frequent cross-country transmission and multiple origins of the virus in Thailand. Furthermore, sequence similarity network analysis identified 33 potentially novel anellovirus species in our data set. Our findings greatly expand the knowledge of anellovirus diversity in Thailand and demonstrate the potential of human whole-genome sequencing data as a valuable resource for viral discovery. Lastly, we highlight and discuss some challenges with the use of the current pairwise sequence similarity-based classification scheme, in particular, how gaps can influence similarity calculation and potentially lead to inconsistencies with a phylogenetic-based classification scheme. IMPORTANCE: Anelloviruses are widespread in humans, yet their diversity remains poorly characterized in many regions, including Thailand. Here, we demonstrate that human sequencing data sets, originally generated without the intention for virome research, can be effectively mined for anellovirus sequences, including complete genomes. Our findings reveal a substantial number of previously unreported anelloviruses in Thailand, significantly expanding the known diversity of the virus. We also highlight potential limitations of the current anellovirus species classification scheme, which is based on pairwise orf1 sequence similarity analysis with a hard threshold cutoff at 69%. Our results reveal that the current scheme can sometimes yield taxonomic groupings that are inconsistent with phylogenetic relationships, particularly when significant alignment gaps are present. Overall, our results show that existing human sequencing data can be effectively repurposed for virus discovery research and suggest the need for more robust and phylogenetically informed classification frameworks as viral sequence databases continue to expand.

Humans↗

PubMed1998

Birthweight of term infants and maternal occupation in a prospective cohort of pregnant women. The ALSPAC Study Team.

OBJECTIVE: To study the relation between birthweight of term infants and maternal occupation. METHODS: Information on job titles since the age of 16, and sociodemographic and other lifestyle factors were obtained by means of questionnaires as part of the Avon longitudinal study of pregnancy and childhood (ALSPAC), from a cohort of 14,000 pregnant women. The British 1990 standard occupational classification was used to code jobs within nine major job groups. RESULTS: For 9282 women who delivered term infants and reported a job for the relevant period, there was a significant difference in mean birthweight among the nine major job groups. A 148 g difference was found between the mean birthweight of infants born to women with professional occupations and those with plant and machine operative jobs. Multiple regression analysis adjusted for sex of infant, parity, maternal height, smoking, caffeine consumption, and race. After adjustment the maternal job was no longer significantly associated with birthweight. CONCLUSION: Despite the absence of a significant association between birthweight and job after adjustment, there were several findings which agreed with publications on maternal occupation and pregnancy outcome. The major job groups with the lowest birthweights included the following jobs; metal forming or welding, electric or electronic work, jobs in the textile trade, and assembling and working with equipment (mobile and stationary). The lack of an association may indicate that the study was of insufficient power to detect a small difference; it may indicate the presence of confounding variables that were not adjusted for or it may indicate that no association exists.

Adolescent↗

PubMed2005

Automating genomic data mining via a sequence-based matrix format and associative rule set.

There is an enormous amount of information encoded in each genome--enough to create living, responsive and adaptive organisms. Raw sequence data alone is not enough to understand function, mechanisms or interactions. Changes in a single base pair can lead to disease, such as sickle-cell anemia, while some large megabase deletions have no apparent phenotypic effect. Genomic features are varied in their data types and annotation of these features is spread across multiple databases. Herein, we develop a method to automate exploration of genomes by iteratively exploring sequence data for correlations and building upon them. First, to integrate and compare different annotation sources, a sequence matrix (SM) is developed to contain position-dependant information. Second, a classification tree is developed for matrix row types, specifying how each data type is to be treated with respect to other data types for analysis purposes. Third, correlative analyses are developed to analyze features of each matrix row in terms of the other rows, guided by the classification tree as to which analyses are appropriate. A prototype was developed and successful in detecting coinciding genomic features among genes, exons, repetitive elements and CpG islands.

Base Sequence↗

PubMed2006

Evaluation and selection of tandem repeat loci for a Brucella MLVA typing assay.

BACKGROUND: The classification of Brucella into species and biovars relies on phenotypic characteristics and sometimes raises difficulties in the interpretation of the results due to an absence of standardization of the typing reagents. In addition, the resolution of this biotyping is moderate and requires the manipulation of the living agent. More efficient DNA-based methods are needed, and this work explores the suitability of multiple locus variable number tandem repeats analysis (MLVA) for both typing and species identification. RESULTS: Eighty tandem repeat loci predicted to be polymorphic by genome sequence analysis of three available Brucella genome sequences were tested for polymorphism by genotyping 21 Brucella strains (18 reference strains representing the six 'classical' species and all biovars as well as 3 marine mammal strains currently recognized as members of two new species). The MLVA data efficiently cluster the strains as expected according to their species and biovar. For practical use, a subset of 15 loci preserving this clustering was selected and applied to the typing of 236 isolates. Using this MLVA-15 assay, the clusters generated correspond to the classical biotyping scheme of Brucella spp. The 15 markers have been divided into two groups, one comprising 8 user-friendly minisatellite markers with a good species identification capability (panel 1) and another complementary group of 7 microsatellite markers with higher discriminatory power (panel 2). CONCLUSION: The MLVA-15 assay can be applied to large collections of Brucella strains with automated or manual procedures, and can be proposed as a complement, or even a substitute, of classical biotyping methods. This is facilitated by the fact that MLVA is based on non-infectious material (DNA) whereas the biotyping procedure itself requires the manipulation of the living agent. The data produced can be queried on a dedicated MLVA web service site.

Animals↗

PubMed2001

Phylogeny of the kinetoplastida: taxonomic problems and insights into the evolution of parasitism.

To further investigate phylogeny of kinetoplastid protozoa, the sequences of small subunit (18S) ribosomal RNA of nine bodonid isolates and ten isolates of insect trypanosomatids have been determined. The root of the kinetoplastid tree was attached to the branch of Bodo designis and/or Cruzella marina. The suborder Trypanosomatina appeared as a monophyletic group, while the suborder Bodonina was paraphyletic. Among bodonid lineages, parasitic organisms were intermingled with free-living ones, implying multiple transitions to parasitism and supporting the 'vertebrate-first hypothesis'. The tree indicated that the genera Cryptobia and Bodo are artificial taxa. Separation of fish cryptobias and Trypanoplasma borreli as different genera was not supported. In trypanosomatids, the genera Leptomonas and Blastocrithidia were polyphyletic, similar to the genera Herpetomonas and Crithidia and in contrast to the monophyletic genera Trypanosoma and Phytomonas. This analysis has shown that the morphological classification of kinetoplastids does not in general reflect their genetic affinities and needs a revision.

Animals↗

PubMed1990

The classification of the low birth-weight infants from the viewpoint of mental development.

Periodical checkups on 206 infants were carried out in order to elucidate which of various factors would pose decisive influence upon the retardation of mental development after birth with the AIKEN method. Correlations between average DQ (development quotient) and figures of physical measurements at birth were sought after. Consequently, weeks of gestation, body weight, cephalic circumference and body length at birth revealed certain correlation with the retardation of mental development. Multiple regression analysis disclosed highly significant correlations of body length and cephalic circumference toward the birth weight. Therefore, both weeks of gestation and birth weight are the direct contributory factors to average development quotient. Based on this result, a prediction equation for the mental development after birth has been proposed. Low average DQ was found in high percentages among infants born with toxemia of pregnancy or premature rupture of membranes. However, it is suggested that they are not the direct causes of such retardation, but are rather provoking short weeks of gestation and low birth weight. In summary, the newborn with less than 37 weeks of gestation and below 2,000 grams of birth weight would be named and classified as a SFD (small for dates) with the problem for mental development (MD-SFD).

Birth Weight↗

PubMed2002

[Icelandic genealogical registry sheds light on the significance of heredity in osteoarthritis].

Osteoarthritis is a heterogeneous and multifactorial disease with many pathogenic mechanisms implicated in its development and progression. Although osteoarthritis is a manifestation of certain metabolic, mechanical or inflammatory events, several distinct forms of osteoarthritis are inherited as dominantly acquired Mendelian traits. Gathering evidence is showing that inheritance and possible mutations in genes associated with osteoarthritis can play a major role in the common form of osteoarthritis in many joints. By the introduction of new biological methods for finding gene defects the search for possible gene defects have taken mainly three forms: (1) Parametric linkage analysis of rare families in which osteoarthritis segregates as a Mendelian trait; (2) model free linkage analysis of affected sibling pairs, and (3) association analysis of known candidate genes. Mutations today known to be associated with osteoarthritis all occur in relatively rare syndromes or diseases, which have osteoarthritis as a major component. In recent years many loci have been found associated with the "common osteoarthritis phenotype". Chromosomes 2, 4, 6, 11 and 16 were identified in multiple genome scans and are therefore the most likely to encode susceptibility. Ongoing studies will lead to classifications of the "common osteoarthritis" based on the exact causative gene defects, rather than on their variable clinical and radiographic phenotype. Hopefully, these studies will lead to future new therapy of osteoarthritis.

Databases, Factual↗

PubMed2003

Predicting length of service provision in school-based occupational therapy.

Parents and school administrators commonly ask how long a child is likely to need school-based occupational therapy services. In an effort to provide a statistically supported answer, a record review of 464 cases of students discharged from school-based occupational therapy services in the past 7 years was performed. This review demonstrated that some general statements about service patterns could be determined for this particular caseload. Of note was the significant variability in length of services for students with multiple disabilities as compared to the more discrete length of service provision for students with speech impairments, learning disabilities and those students without a specific classification. The applicability to other practice settings is limited, but this study serves as a beginning point for discussion on the topic.

Adolescent↗

PubMed1993

[Multiple personality disorder: old concepts presented as new].

The rapid increase in numbers of MPD patients in the Anglo-American literature requires discussion of the diagnostic concept. The classification of MPD as Dissociative Disorders by DSM-III-R and ICD-10 follows the traditional conceptualization of hysteria and hypnosis. In the view of the majority of modern authors child abuse appears as a new etiological issue. This theme highly sensitive is critically discussed against the background of older psychopathological concepts of forgetting. A careful analysis of personality traits and motivation in the individual case help to avoid overuse of the new diagnostic label.

Child↗

PubMed1997

[Clinical and biological markers of secondary uveitis: results of a discriminant analysis].

BACKGROUND: The association of uveitis and systemic disease is well known. Patients suffering from uveitis often undergo a extensive battery of tests in order to detect underlying disease, but the efficiency of such screening is uncertain. The aim of this study was to investigate useful clinical data for recognizing secondary uveitis. PATIENTS AND METHODS: We conducted a prospective analysis of 115 patients with uveitis of unknown etiology. All of them were included in an extensive protocol study. Four groups were considered: specific ocular disease (SOD), idiopathic uveitis, HLA-B27 associated uveitis without arthritis (HLA-B27-AU) and secondary uveitis. Groups were compared by analysis of variance for continuous variables, and chi 2 test or Student's t-test for discrete variables. A stepwise multiple discriminant analysis was performed for ranking the variables in order of their usefulness for distinguishing idiopathic and secondary uveitis. RESULTS: We diagnosed 11 SOD (9.6%), 54 idiopathic uveitis (47%), 6 HLA-B27-AU (5.2%) and 41 secondary uveitis (35.7%). The discriminant analysis showed that age, an elevated erythrocyte sedimentation rate, presence of cutaneous lesion, joint pain and genital ulcers are the strongest predictors of secondary uveitis. This model classification functions detected 92.5% of idiopathic uveitis and 72% of secondary uveitis. The global percentage of patients with a correct diagnosis was 84.6%. CONCLUSIONS: Anamnesis, physical examination and basic laboratory tests are sufficient tools for the diagnostic approach of the majority of patients with uveitis. Subsequent diagnostic procedures must be planned in each patient to confirm a specific disease.

Adolescent↗