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PubMed1987

The immunologic approach to analysis of malignant lymphoma. Mantle zone lymphoma of the ileocecal region.

We studied an unusual type of lymphoma of the ileocecal region using an established protocol that combines morphologic, flow cytometric, and immunohistochemical analyses. This lymphoma grew as multiple submucosal nodules, some of which had coalesced into a mass in the terminal ileum. Histologically, the lesion resembled a lymphoma of follicular center-cell origin except for germinal centers that appeared reactive and greatly expanded follicular mantles. Flow cytometric studies showed that the lymphoma contained a monoclonal, kappa+ population of B-lymphocytes. Evaluation of sections of frozen tissue by an immunoperoxidase technique revealed that the germinal centers were polyclonal (nonneoplastic) and that the neoplastic cells were confined to the mantle zone. The additional information led to classification of the neoplasm as the mantle zone variant of intermediate lymphocytic lymphoma. This type of lymphoma may pursue a more aggressive course than a follicular lymphoma derived from the germinal center. We review our general approach to the analysis of hematolymphoid neoplasms and discuss how certain techniques may be useful adjuncts in the evaluation of these types of tumors.

Antibodies, Monoclonal↗

PubMed2006

Forced expiratory volume in 1 second percentage improves the classification of severity among children with asthma.

OBJECTIVE: Spirometry is an important component of the National Asthma Education and Prevention Program guidelines for asthma, yet published data show variable associations between forced expiratory volume in 1 second percentage (FEV1%) predicted, symptoms and health care utilization. The objective of this analysis was to examine the association between FEV1% and future risk of exacerbations among a well-characterized population of children with asthma. METHODS: Using data that are available from the Childhood Asthma Management Program, we examined the relationship between prebronchodilator FEV1% and important clinical outcomes. Multiple observations of FEV1 were available for each patient; multivariate regression analysis, using a general estimating equation approach, was used to control for the correlation between repeated measurements among individuals and potential confounders. FEV1% was categorized into 4 levels and as a continuous variable. Outcomes of interest included mean symptom score (0-3), episode-free days, and asthma-related events (oral steroid use, emergency department visits, and hospitalizations) during the ensuing 4-month period. Our analysis was limited to the placebo group (N = 417). RESULTS: We observed a clear relationship between prebronchodilator FEV1% and important clinical outcomes. In multivariable models that simultaneously controlled for covariates of interest, age at baseline, time, previous event history, and nocturnal awakenings, a significant relationship between FEV1% and asthma symptoms and serious asthma exacerbations (oral steroids, emergency department visits, and hospitalizations) was observed. Compared with children with an FEV1% > or = 100%, children with FEV1% 80% to 99%, 60% to 79%, and < 60% were 1.3, 1.8, and 4.8, respectively, more likely to have a serious asthma exacerbation during the ensuing 4 months. CONCLUSIONS. In children with mild to moderate asthma, FEV1% predicted is independently associated with future asthma symptoms and health care utilization. Previous asthma-related hospitalizations and nocturnal symptoms also were independently associated with risk for future adverse events. FEV1 is an important component of asthma health status and asthma severity classification.

Albuterol↗

PubMed1993

The analysis of egg wash water for the rapid assessment of microbiological quality.

A total of 101 egg wash water samples from five different egg grading stations in eastern Ontario were analyzed for a variety of physical and chemical variables in an attempt to find a correlation with total bacterial counts. Temperature, pH, total chlorine, and percentage transmission at 600 nm (%T) were found to be significant variables, and a multiple regression equation was derived that accounted for 65% of the total variation. The equation was used to classify wash water samples as acceptable (< or = 10(5) cfu/mL) or unacceptable and correctly classified 77.2% of the samples. Classification of a second (validation) data set from 58 wash water samples was correctly predicted in 72% of the cases. The predictive value of the equation was especially good for those wash water samples obtained from stations that had used a chlorinated alkaline detergent, 90.4 and 100% for the modeling and validation data, respectively. Maintenance of wash water at recommended levels for temperature and pH (i.e., > or = 40 C and pH > or = 10) was insufficient to ensure bacterial numbers would be < or = 10(5) cfu/mL. Under normal operating conditions a minimum total available chlorine concentration of .45 mg/L should be maintained in wash water to ensure that bacterial numbers are kept at an acceptable level. Monitoring of temperature, pH, total chlorine, and %T will assist in maintaining wash water quality and minimize the number of samples returned to laboratories for microbiological analysis.

Animals↗

PubMed1986

Ovarian cancer metastatic to the breast.

The breast is an uncommon site for metastasis from epithelial ovarian cancer. Such lesions are purportedly secondary to blood-borne metastases. The accurate classification of ovarian epithelial neoplasms is the cornerstone of decisions regarding therapy and prognosis. Taylor, in 1929, reported a hyperplastic variety of papillary cystadenoma which, on occasion, produced multiple implants on the peritoneum but usually behaved in a benign fashion. The International Federation of Gynecologists and Obstetricians adopted a classification of benign cystadenomas, cystadenocarcinomas of low malignant potential (LMP), and cystadenocarcinomas. The serous tumors of LMP rarely metastasize outside of the abdominopelvic cavity. This case, of a serous tumor of LMP with breast metastasis, permits an analysis of metastatic breast lesions secondary to epithelial ovarian cancer.

Adult↗

PubMed2001

The main biological determinants of tumor line taxonomy elucidated by a principal component analysis of microarray data.

By using principal components analysis (PCA) we demonstrate here that the information relevant to tumor line classification linked to the activity of 1375 genes expressed in 60 tumor cell lines can be reproduced by only five independent components. These components can be interpreted as cell motility and migration, cellular trafficking and endo/exocytosis, and epithelial character. PCA, at odds with cluster analysis methods routinely used in microarray analysis, allows for the participation of individual genes to multiple biochemical pathways, while assigning to each cell line a quantitative score reflecting fundamental biological functions.

Cell Movement↗

PubMed2000

Psychosocial factors and male seminal parameters.

The relationships between (a) alexithymia, (b) extroversion (E), neuroticism (N), psychoticism (P), (c) coping style towards stressors, and seminal parameters, were assessed in 132 males on their first seminal fluid examination by means of a multivariate approach. They were given the TAS-20, the EPQ, and the Coping Inventory for Stressful Situations (CISS). Seminal parameters were: (1) sperm concentration; (2) total sperm count; (3) forward motility; (4) atypical forms. Multiple regressions considering quantitative parameters of seminal status as criterion showed a negative relationship with P, difficulty describing feelings (DDF), while a positive relationship was found for N, and emotion-oriented coping. A discriminant analysis also showed that P, N and DDF distinguished between two groups of normozoospermic and oligozoospermic subjects with a high probability of correct classifications. Results confirm the hypothesis that biological and psychological variables are not completely independent or randomly related in people with an impaired seminal status, although the correlations between psychosocial and biological data are not very strong.

Adaptation, Psychological↗

PubMed2002

Pain classification following spinal cord injury: the utility of verbal descriptors.

OBJECTIVES: To determine the predictive utility of verbal descriptors to distinguish between pain types following spinal cord injury (SCI). DESIGN: Cross-sectional. SETTING: USA. METHODS: Participants (n=29) completed the Short Form - McGill Pain Questionnaire (SF-MPQ) for each pain site reported. A total of 64 pain sites were reported with 80% of the sample reporting multiple pain sites. Each pain site was categorized using three different SCI pain classification schemes. The predictive utility of verbal descriptors to distinguish between pain types was examined statistically using (1) each word separately, (2) a combination of words (ie, the SF-MPQ total subscales, the number of words chosen on each scale), and (3) discriminant function analysis. RESULTS: There was a substantial overlap in the use of verbal descriptors across pain types. Few differences across pain types were found for endorsement of individual words, and differences across pain types were not found for any of the word combination scores. The majority of the verbal descriptors did not enter the step-wise discriminant functions for each SCI pain classification scheme, however, 'tingling' and 'aching' showed modest predictive utility for neuropathic and musculoskeletal pain, respectively. Correct classification was in the low range (ie, 39% to 82%, average=60%, with a 33% chance level). All three pain classification schemes showed the same general pattern of results. CONCLUSION: In general, verbal descriptors alone offered marginal utility with regard to identifying specific pain types following SCI. Future directions alone and implications are discussed.

Adult↗

PubMed2006

Genome-controlled reverse transcriptase-polymerase chain reaction for targeted gene-expression analysis.

OBJECTIVE: Although gene-expression profiling has an important part to play in the classification of tumours and premalignant conditions, reproducibility of the present polymerase chain reaction (PCR)-based quantitative techniques needs to be improved for diagnostic purposes and to enable analysis of gene expression in formalin-fixed paraffin-embedded (FFPE) tissue samples. We have developed reverse transcriptase-PCR-based technology for quantitative assessment of the relative content of multiple mRNA transcripts in small tissue or cell samples. MATERIAL AND METHODS: A multiplexed sequence modifying cDNA synthesis reaction is performed with this technique to create a 4-5 degrees increase in the melting temperature of subsequent short (56-64 bp) PCR amplicons. Each cDNA template is competitively co-amplified with genomic DNA, which serves as a universal internal standard. The relative amounts of cDNA and genomic DNA-derived amplicons are quantified in-tube by homogeneous melting curve analysis. RESULTS: The dynamic range of the assay was three orders of magnitude, while the detection limit was 100 cDNA molecules. A prototype assay, consisting of the analysis of eight genes, displayed good reproducibility (inter-assay CV 5-20 %) compared to the TaqMan assay (inter-assay CV 7-43 %). Gene-expression analysis could be performed in 20 of 20 (100 %) archival frozen samples, in 30 of 35 (86 %) archival FFPE samples and in 26 of 27 (96 %) endoscopic biopsies. CONCLUSIONS: We demonstrate that this new technique enables accurate analysis of mRNA expression in cultured cells and endoscopic tissue biopsies. Sensitive analysis FFPE tissue is also possible thanks to the short PCR amplicons.

Biopsy↗

PubMed1993

How to see characteristics of structural parameters in QSAR analysis: descriptor mapping using neural networks.

In addition to its outstanding abilities in both classification and fitting, the neural network can also accurately predict the values of the untrained region. To rationalize this ability of prediction, the authors mathematically discussed the valid region of prediction. Based on such a background, the authors proposed "descriptor mapping" in the QSAR analysis, which visualizes the nonlinear dependencies between structural parameters. A variable of the linear multiple regression analysis in the QSAR study is supposed to be linear to the biological intensity and is independent of other variables. Analysis by the descriptor mapping method discloses the reality.

Anticarcinogenic Agents↗

PubMed2004

Phylogenomic inference of protein molecular function: advances and challenges.

MOTIVATION: Protein families evolve a multiplicity of functions through gene duplication, speciation and other processes. As a number of studies have shown, standard methods of protein function prediction produce systematic errors on these data. Phylogenomic analysis--combining phylogenetic tree construction, integration of experimental data and differentiation of orthologs and paralogs--has been proposed to address these errors and improve the accuracy of functional classification. The explicit integration of structure prediction and analysis in this framework, which we call structural phylogenomics, provides additional insights into protein superfamily evolution. RESULTS: Results of protein functional classification using phylogenomic analysis show fewer expected false positives overall than when pairwise methods of functional classification are employed. We present an overview of the motivations and fundamental principles of phylogenomic analysis, new methods developed for the key tasks, benchmark datasets for these tasks (when available) and suggest procedures to increase accuracy. We also discuss some of the methods used in the Celera Genomics high-throughput phylogenomic classification of the human genome. AVAILABILITY: Software tools from the Berkeley Phylogenomics Group are available at http://phylogenomics.berkeley.edu

Algorithms↗

PubMed1997

Which clinical features differentiate progressive supranuclear palsy (Steele-Richardson-Olszewski syndrome) from related disorders? A clinicopathological study.

The difficulty in differentiating progressive supranuclear palsy (PSP, also called Steele-Richardson-Olszewski syndrome) from other related disorders was the incentive for a study to determine the clinical features that best distinguish PSP. Logistic regression and classification and regression tree analysis (CART) were used to analyse data obtained at the first visit from a sample of 83 patients with a clinical history of parkinsonism or dementia confirmed neuropathologically, including PSP (n = 24), corticobasal degeneration (n = 11), Parkinson's disease (PD, n = 11), diffuse Lewy body disease (n = 14). Pick's disease (n = 8) and multiple system atrophy (MSA, n = 15). Supranuclear vertical gaze palsy, moderate or severe postural instability and falls during the first year after onset of symptoms classified the sample with 9% error using logistic regression analysis. The CART identified similar features and was also helpful in identifying particular attributes that separate PSP from each of the other disorders. Unstable gait, absence of tremor-dominant disease and absence of a response to levodopa differentiated PSP from PD. Supranuclear vertical gaze palsy, gait instability and the absence of delusions distinguished PSP from diffuse Lewy body disease. Supranuclear vertical gaze palsy and increased age at symptom-onset distinguished PSP from MSA. Gait abnormality, severe upward gaze palsy, bilateral bradykinesia and absence of alien limb syndorme separated PSP from corticobasal degeneration. Postural instability successfully classified PSP from Pick's disease. The present study may help to minimize the difficulties neurologists experience when attempting to classify these disorders at early stages.

Fixation, Ocular↗

PubMed1996

Outcomes of patients with pelvic-ring fractures managed by open reduction internal fixation.

The purpose of this multiple-subject case report is to describe the physical impairments, disabilities, and handicaps of patients with multiple traumas and pelvic-ring fractures after management with open reduction internal fixation. Nineteen men and 12 women, with a mean age of 38+/-16 years (chi+/-SD), were interviewed and examined at least 1 year (chi+/-14.5 months) after sustaining multiple traumas, including an unstable pelvic-ring fracture that was repaired by open reduction internal fixation. Disabilities and handicaps were assessed using the Oswestry Low Back Pain Questionnaire and the Sickness Impact Profile (SIP). Assessments of physical performance consisted of lift capacity, the amount of forward bending, and gait. A descriptive analysis by age and pelvic fracture classification is reported. The < or = 50-year-old group had the best physical testing scores, except for the lifting test. The > 50-year-old group had the lowest scores. Subjects with B1-class "open-book" pelvic fractures had a tendency to score higher in individual SIP categories. The average SIP scores of 9.34+/-7.47 for the total SIP score, 7.79+/-6.93 for the physical dimension, and 8.24+/-9.61 for the psychosocial dimension represent mild disability. The mean Oswestry score of 13.26%+/-15.41% also represents mild disability. Some subjects demonstrated impairments, disabilities, and handicaps 1 year postoperatively, but for the most part the subjects recovered almost all lost function. The data and clinical management information can be used as a basis of comparison for treatment and research with these types of patients.

Adolescent↗

PubMed1994

Further studies on the electrodiagnosis of diabetic peripheral polyneuropathy using discriminant function analysis.

Discriminant function analysis can be useful when applied to multiple nerve conduction parameters for diabetic and nondiabetic subjects to reveal the essential dimension along which key neuropathic differences occur between these groups. In this study, 19 electrophysiologic parameters were used in a stepwise discriminant function analysis to reveal a highly significant dimension of intergroup differences between 67 diabetic and 75 normal adult Japanese-American males. The classification functions thereby derived are more sensitive and specific than those reported previously for this population. Furthermore, when 72 additional subjects with impaired glucose tolerance were examined, they showed considerable overlap with the normal and separation from the diabetic groups, respectively. Their intermediate position between normal and diabetics in the key discriminant dimension indicates that essential neuropathic change is, at most, incipient in this latter group.

Cross-Sectional Studies↗

PubMedDate not supplied

[Subjective sleep quality and spectral analysis of electroencephalography during nocturnal sleep].

INTRODUCTION: The relation between subjective sleep quality and the stages of polysomnography is unclear. Computerized sleep analysis provides a reliable tool for the study of sleep dynamics. OBJECTIVE: To study the relation between subjective sleep quality and spectral EEG parameters during nocturnal sleep. MATERIAL AND METHODS: Nocturnal sleep were recorded ambulatory in 26 subjects aged from 8 to 63. The following variables were extracted from EEG signal (Fz-Pz) quantified through the Fast Fourier Transformation (FFT): delta maximum, spectral peak, delta sleep time, efficiency and desynchronized sleep. A sleep diary was administered in the morning to assess the subjective sleep quality. Multiple regression and Anova were used for statistical analysis. RESULTS: Efficiency and delta maximum became significant predictors accounting for 54% of subjective sleep variance. The item 'how was your sleep?' was answered in a different way according to the delta maximum. CONCLUSIONS: Sleep depth, measured by spectral analysis, is an important predictor of the subjective sleep quality. The sleep classification in discrete stages ignores this feature.

Adolescent↗

PubMed2005

Does the diameter of an endometrioma predict the extent of pelvic adhesions associated with endometriosis?

OBJECTIVE: To correlate ovarian endometrioma diameter with the extent of pelvic adhesions. STUDY DESIGN: Forty women with unilateral ovarian cysts thought to be endometriomas were prospectively recruited. The interventions were transvaginal ultrasound to measure the size of the ovarian endometrioma and a laparoscopic surgical procedure, including detailed pelvic assessment. Main outcome measures were pelvic adhesion scores using the American Fertility Society revised classification of endometriosis. RESULTS: Thirty-two women met the inclusion criteria. Twelve had an endometrioma < 3 cm in diameter; 12, 3-5 cm; and 8, > 5 cm. Adhesion scores from various anatomic areas did not differ across these 3 groups. No correlation between the size of the endometrioma and associated pelvic adhesions was found using multiple regression analysis. CONCLUSION: The size of an endometrioma measured by transvaginal ultrasound does not correlate with the extent of adhesive disease. Small (< 3 cm) endometriomas may be associated with a considerable degree of pelvic adhesions.

Adult↗

PubMed1985

Variables discriminating residential placement of severely handicapped children.

The relationship of 11 social and status variables to two placement groups of severely handicapped children (home and community-based residential facility). Using a multiple discriminant analysis, we found that 6 of these variables (child's age, parental feelings about the suggestion to institutionalize, religiosity, mother's age, child's age at first words, and child's age at school entry) contributed significantly to the discrimination between the two groups. When the resulting coefficient of discrimination was applied to a subsample, statistical classification agreed with known placement in 75.68% of the cases, indicating a high degree of discrimination between children residing at home and in residential settings on the variables studied.

Adolescent↗

PubMedDate not supplied

[The surgical treatment of arterial aneurysms in the acute period of subarachnoid hemorrhage].

The paper presents the surgical outcomes of 300 patients with brain arterial aneurysms. A total of 43% of the patients were admitted to the unit within the first 72 hours of the onset of hemorrhage, 165 patients were operated on within the first fortnight, 135 were operated on in later periods. The aneurysms of the anterior communicating artery, internal carotid, middle cerebral artery were 42, 24, and 22%, respectively. Multiple aneurysms were 12% according to the Hunt and Hess classification, the preoperative severity of the patients was as follows: Degree I, 39 (13%), patients, Degree II, 130 (43%), Degree III, 106 (36%), Degree IV, 18 (6%), Degree V, 7 (2%). In 14% of the patients, aneurysm rupture was accompanied by the formation of intracerebral hematoma. The qualitative analysis of angiograms revealed vascular spasm in 70% of cases, the quantitative one indicated it in 80%. Aneurysm clipping was performed in 269 patients, its wrapping with a free muscle flap was done in 31 patients. Among the patients operated on, the mortality was 35% in the first fortnight of the onset of the disease and 17% during operations in later periods.

Aneurysm, Ruptured↗

PubMed1996

Mobility in the cervico-thoracic motion segment: an indicative factor of musculo-skeletal neck-shoulder pain.

The aim of the study was first to evaluate whether mobility in the cervico-thoracic motion segment is an indicative factor of musculo-skeletal neck-shoulder pain and secondly to compare differences in individual factors between cases and controls for female and male subjects. One-hundred-and-forty-two male electricians and 139 female laundry workers participated in a cross-sectional study. An examination of the Cervico-Thoracic Ratio and a classification of mobility at level C7-T1 was done. All subjects answered a questionnaire about musculo-skeletal complaints. The analysis of relationship between relative flexion mobility in motion segments C7-T5 and neck-shoulder pain showed significant relationships between mobility in specific motion segments and neck-shoulder pain. The overall fit of the multiple regression analysis explained 10% of the variation in neck index (N1) for subjects classified as hypomobile at level C7-T1 and 18% for subjects classified as having an inverse C7-T1 function. Both female and male subjects classified as hypomobile at level C7-T1 showed elevated odds ratios of 2.7 and 2.2, respectively, to have had more than 7 days of neck pain during the previous 12 months, compared to subjects classified as having ordinary mobility at level C7-T1. The factor age showed that young subjects with hypoar hypermobility at level C7-T1 showed elevated odds ratios for neck pain compared to subjects with ordinary mobility in the same age group. In old subjects hypermobility at level C7-T1 was protective compared to subjects with ordinary mobility in the same age group. The factor number of working years showed significant difference between cases and controls among female subjects in the ordinary and hypermobile classes. The factor height showed no significant differences between female or male cases and controls; it did show significant correlation to C7-T1 mobility among female subjects, but not among male subjects. The factors exercise and smoking showed significant differences between cases and controls among female subjects in the ordinary mobility class. The conclusion was that relative flexion mobility is a factor related to the development of neck-shoulder pain rather than the cause of pain.

Adolescent↗