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PubMed1983

Simulation of psychosis on a multiple-choice projective test.

The ability of a new multiple-choice group Rorschach instrument to differentiate 62 undergraduate students asked to simulate psychosis from 75 students and 55 schizophrenics given standard instructions was investigated. For each of 50 responses to miniature inkblots, normals and psychotics chose one of four alternative answers as most descriptive of what the stimulus looked like. Simulators responded as they thought a psychotic or insane person would. As hypothesized, simulators chose significantly more "good form but bizarre wording" responses than normals or psychotics, suggesting that the test is promising as a practical clinical indicator of attempts to simulate psychosis.

Adult↗

PubMed2002

Extension of conditional model-free likelihood-based linkage analysis to additive and other models.

We have previously described extending our method of 'model-free' linkage analysis, implemented in the MFLINK program, in order to deal with liability classes. This allows a new form of conditional two-locus linkage analysis, meaning that the genotypes of a known risk locus can be used to define liability classes so that their effects can be incorporated in tests for linkage at additional loci. In this method, relationships between transmission models for different liability classes were constrained so that there was a constant multiplicative effect on penetrance values. Here we present further extensions to the method to allow for different relationships. In particular, rather than only having a multiplicative effect on risk of affection we now allow specification of a multiplicative effect on risk of non-affection, or a combination of both relationships, across liability classes. We now also allow specification of an additive effect on penetrance. By way of example, we apply these methods to genome scan data for Alzheimer's disease using apolipoprotein E genotype to define liability classes. We show that, although in general the different methods produce results which tend to be quite highly correlated, certain markers can produce quite different results according to the method applied and that these could well lead to differences of interpretation. Without knowing a priori which relationship is likely to be most appropriate to describe the overall combined effect of the two loci one might be obliged to apply a number of different methods. This in turn may lead to the familiar difficulties associated with multiple testing. Nevertheless, the new method allows researchers greater flexibility in analysing linkage data for diseases in which one or more risk polymorphisms have already been identified.

Genetic Linkage↗

PubMed2006

JProGO: a novel tool for the functional interpretation of prokaryotic microarray data using Gene Ontology information.

A novel program suite was implemented for the functional interpretation of high-throughput gene expression data based on the identification of Gene Ontology (GO) nodes. The focus of the analysis lies on the interpretation of microarray data from prokaryotes. The three well established statistical methods of the threshold value-based Fisher's exact test, as well as the threshold value-independent Kolmogorov-Smirnov and Student's t-test were employed in order to identify the groups of genes with a significantly altered expression profile. Furthermore, we provide the application of the rank-based unpaired Wilcoxon's test for a GO-based microarray data interpretation. Further features of the program include recognition of the alternative gene names and the correction for multiple testing. Obtained results are visualized interactively both as a table and as a GO subgraph including all significant nodes. Currently, JProGO enables the analysis of microarray data from more than 20 different prokaryotic species, including all important model organisms, and thus constitutes a useful web service for the microbial research community. JProGO is freely accessible via the web at the following address: http://www.jprogo.de.

Archaea↗

PubMed2000

Survey of preferred tests for diagnosis of the tear film and dry eye.

PURPOSE: To survey practitioners in the tear film/dry eye field for their preferred diagnostic methods for the evaluation of the tear film and dry eye syndrome. METHODS: A survey was given to 36 optometrists and 41 ophthalmologists with backgrounds in the area of tear film and dry eye syndrome to find their preferred test if only one diagnostic option was available for tear film evaluation. Second, third, and fourth choices were also recorded, as well as any additional comments. RESULTS: Sixty-eight practitioners completed the survey. No one single test was a dominant first choice of the majority of respondents in either profession. History and/or dry eye questionnaire was the most frequent response to the question addressing the use of only one test (28%). The second most frequently chosen test was fluorescein break-up time (FBUT) (19%), followed by fluorescein staining (13%), and rose bengal (10%). The Schirmer test was most frequently included as one of the four choices (62%), although it was the first choice of only 9%. CONCLUSION: The importance of multiple tests in the evaluation of tear film disorders is overwhelmingly acknowledged, with patient history/dry eye questionnaires, FBUT, ocular surface staining, and the Schirmer test being the preferred diagnostic tools.

Contrast Media↗

PubMed2025

A spectral framework to map QTLs affecting joint differential networks of gene co-expression.

Studying the mechanisms underlying the genotype-phenotype association is crucial in genetics. Gene expression studies have deepened our understanding of the genotype  →  expression  →  phenotype mechanisms. However, traditional expression quantitative trait loci (eQTL) methods often overlook the critical role of gene co-expression networks in translating genotype into phenotype. This gap highlights the need for more powerful statistical methods to analyze genotype  →  network  →  phenotype mechanism. Here, we develop a network-based method, called spectral network quantitative trait loci analysis (snQTL), to map quantitative trait loci affecting gene co-expression networks. Our approach tests the association between genotypes and joint differential networks of gene co-expression via a tensor-based spectral statistics, thereby overcoming the ubiquitous multiple testing challenges in existing methods. We demonstrate the effectiveness of snQTL in the analysis of three-spined stickleback (Gasterosteus aculeatus) data. Compared to conventional methods, our method snQTL uncovers chromosomal regions affecting gene co-expression networks, including one strong candidate gene that would have been missed by traditional eQTL analyses. Our framework suggests the limitation of current approaches and offers a powerful network-based tool for functional loci discoveries.

Quantitative Trait Loci↗

PubMed2003

Overflow movements predict impaired response inhibition in children with ADHD.

Neurologic models proposed to explain mechanisms underlying ADHD have emphasized deficits in response inhibition. Age-inappropriate overflow movements, e.g., mirror movements, are motor signs thought to reflect immaturity in cortical systems involved in automatically (unconsciously, without explicit effort) inhibiting extraneous movement. We investigated the hypothesis that the presence of excessive overflow movements would predict measures of conscious, effortful response inhibition (conflicting and contralateral motor response tests) in children with ADHD. 42 children with ADHD and 30 controls, ages 8 through 12 years, participated. Children with ADHD showed significantly more overflow movements than did controls and made more errors on the conflicting and contralateral motor response tests. Multiple linear regression analysis indicated that overflow movements predicted performance on measures of motor response inhibition. For one of those measures, the contralateral motor response test, there was a significant interaction with diagnosis, such that overflow predicted response inhibition in ADHD but not in controls. The findings suggest that overflow movements, which can be readily observed as part of clinical examination, are more evident in children with ADHD. Positive correlations between measures of overflow movements and measures of response inhibition suggest that closely associated neural mechanisms underlie these deficits and support hypotheses that age-inappropriate overflow reflects immaturity of cortical systems involved in automatic inhibition.

Attention Deficit Disorder with Hyperactivity↗

PubMedDate not supplied

Antigenic proteins in latex glove extracts: sources of variability.

Antigenic protein levels in commercially available latex medical gloves were studied. For comparison, the gloves were divided into four main groups; powdered examination, powder-free examination, powdered surgical, and powder-free surgical. Residual protein levels of 91 different glove brands were determined using the LEAP (latex ELISA for antigenic proteins) assay and found to be extremely variable. The possible sources of variability were investigated. Lot-to-lot variability was determined by testing multiple lots of five different brands of surgical gloves. The authors also determined glove-to-glove variability, variability within an individual glove, and test-method variability. It was observed that lot-to-lot variability (25-61% relative standard deviation--RSD) and glove-to-glove variability (51% RSD) were of similar magnitude and accounted for most of the variability found within a given brand of gloves. However, the greatest source of variability identified was brand-to-brand variability (143-283% RSD).

Antigens↗

PubMed1993

Diffuse cutaneous leishmaniasis in a cat.

An adult long-haired domestic cat native to South Texas developed signs consistent with diffuse cutaneous leishmaniasis. Cutaneous leishmaniasis, caused by Leishmania mexicana, was initially diagnosed from lesions confined to the left ear. A radical pinnectomy was done and the cat was returned to its owner. Two years later, lesions developed at the stump, and lesions later developed on the cat's muzzle and nasal mucosa. All of the lesions contained numerous L mexicana amastigotes. Several treatment regimens were attempted, but without evidence of resolution. The cat was tested multiple times for evidence of impaired immunologic competence and was found to be normal. The cat failed to respond to Leishmania antigen given interdermally (Montenegro test) on several occasions. On one occasion, however, there was partial regression of the lesions following the Montenegro test. Cats in areas endemic for cutaneous leishmaniasis (South Texas) may serve as sentinels for the agent. The epidemiology of the infection in this area is largely unknown, as is the importance of cats in the spread of disease.

Animals↗

PubMed2001

Triple lipid screening test: a homogeneous sequential assay for HDL-cholesterol, total cholesterol, and triglycerides.

BACKGROUND: The analysis of lipids in serum lipoprotein fractions is useful in assessing the risk for coronary artery disease, but it typically involves performing multiple tests. An automated single-tube assay, referred to as the triple lipid screening (TLS) test, can be used for measuring HDL-cholesterol (HDL-C), total cholesterol, and triglycerides (TGs) with no specimen pretreatment. METHODS: The first part of the assay is based on a homogeneous assay for HDL-C that uses either an anti-apolipoprotein B antibody (TLS-A test) or a polyanion (TLS-B test) that blocks the enzymatic measurement of cholesterol on the non-HDL fraction. After the addition of deoxycholate, which solubilizes the unreacted cholesterol from the non-HDL fraction, the remaining cholesterol in the sample is subsequently measured enzymatically. Using the same enzyme detection system as the cholesterol assay, TGs are measured in the last step, after the addition of the enzymes for the TG assay. RESULTS: The TLS assay (y) had acceptable analytic performance and compared favorably with standard tests (x) for each analyte: for HDL-C, TLS-A = 0.99x + 0.19 (R = 0.980); TLS-B = 1.00x - 0.15 (R = 0.974); for total cholesterol, TLS-A = 1.03x + 0.12 (R = 0.997); TLS-B = 1.07x - 0.30 (R = 0.965); and for TGs, TLS-A = 1.02x + 0.02 (R = 0.988); TLS-B = 1.04x - 0.28 (R = 0.980). CONCLUSIONS: The TLS test is a single-tube homogeneous assay for the analysis of all of the major serum lipoprotein fractions and can be used as a simple screening test for the detection of hyperlipidemia.

Autoanalysis↗

PubMed2006

Faecal coliform bacteria in Febros river (northwest Portugal): temporal variation, correlation with water parameters, and species identification.

Febros river water was sampled weekly, during 35 successive weeks, and analyzed for microbiological (total coliforms, faecal coliforms, faecal streptococci and enterococci) and chemical-physical (ammonia and temperature) parameters. All microbiological parameters were highly correlated with each other and with ammonia, suggesting that the simultaneous determination of all variables currently in use in the evaluation of the microbiological quality of waters is probably redundant, and could be simplified, and that ammonia should be tested as a sentinel parameter of the microbiological pollution load of Febros river. From the strains isolated from positive tubes of the faecal coliforms test (multiple tube fermentation technique) and retested in this assay, Escherichia coli, Klebsiella oxytoca and Klebsiella pneumoniae subsp. pneumoniae strains were positive, indicating that the faecal coliforms test is not totally specific for Escherichia coli, and can detect other bacteria. Considering that these Klebsiella spp. are not necessarily of faecal origin, it was concluded that the faecal coliforms test can overestimate true faecal pollution. From the strains isolated from positive tubes of the faecal coliforms procedure, only Escherichia coli strains were clearly positive in the beta-D-glucuronidase test. All other species were negative or very weakly positive, suggesting that the assay of the beta-D-glucuronidase activity is less prone to false positives than the faecal coliforms test in the quantification of Escherichia coli in environmental waters.

Ammonia↗

PubMed1996

Finding genetic markers for complex phenotypic traits in parasites.

The identification, mapping and eventual cloning of genes which determine or influence important epidemiological traits in parasites can have great benefits for the control of parasitic disease. In this review, strategies are outlined for identifying genetic markers for complex, quantitative traits. A genetic marker is a variable DNA sequence which co-occurs with a variable quantitative trait. Candidate markers are chosen because they are thought to directly influence the trait whereas random markers are expected to be linked to another DNA sequence which influences the trait. Association studies compare the value of a quantitative trait between different marker genotype classes in a population, without regard to family structure. Linkage studies compare the value of a quantitative trait between marker genotype classes within families or within a population (usually derived from a cross between inbred lines) which is segregating for both marker and quantitative trait loci. The most commonly used analytical methods for determining the significance of association or linkage between marker and quantitative trait loci, and for estimating parameters such as recombination rate and quantitative gene action, are least-squares and maximum likelihood. Both methods may be used to test either single markers or the interval between flanking markers, and both suffer from the need to minimize type I and type II error rates with multiple tests.

Animals↗

PubMed2001

False positives and false negatives in genome scans.

It is emphasized that two types of errors are made in the testing of a hypothesis, false positive (type I) and false negative (type II). Genome-wide scans involving many markers give rise to the problem of multiple testing, which results in an increased number of false positives, thus necessitating a correction in the nominal significance level. While the literature has concentrated reasonably heavily on controlling false positives in genomic scans, the need to control false negatives has been largely neglected. This chapter highlights this need and attempts to strike a balance between the two error types. The need to develop alternative methods for discriminating between false positives and true positives is also stressed.

Chromosome Mapping↗

PubMed2002

How comparable are tests of apraxia?

OBJECTIVE: To compare commonly used tests for the diagnosis of apraxia. MEASURES: People with unilateral left hemisphere lesions, diagnosed with apraxia, were compared in their scoring on commonly used tests for apraxia (n = 17). SETTING: Rivermead Rehabilitation Centre, Oxford, England, a specialist inpatient neurological unit. RESULTS: Production moment correlations were low, or did not reach significance level between three tests for ideomotor apraxia (r = 0.46 p < 0.05 one-tailed test, r = 0.005 NS, r = -0.23 NS, df = 15). Six of the seventeen apraxic patients scored above cut-off point on one test, but below cut-off point on others, indicating that commonly used tests for apraxia may not be reliable for diagnosis if used singly. Internal consistency within tests was also variable (Cronbach's alpha 0.72, 0.85, 0.85). CONCLUSION: The commonly used tests for apraxia may identify different people as 'apraxic', possibly by eliciting different aspects of apraxia and identifying potential subtypes of the condition. The use of multiple tests is, therefore, recommended in order to identify people with apraxia. The need for repeat reliability studies for apraxia assessments, together with a search for a 'gold standard' test is apparent.

Aged↗

PubMed2004

A multistage testing strategy for detection of quantitative trait Loci affecting disease resistance in Atlantic salmon.

A multistage testing strategy to detect QTL for resistance to infectious salmon anemia (ISA) in Atlantic salmon is proposed. First, genotyping of amplified fragment length polymorphisms (AFLP) and a transmission disequilibrium test (TDT) were carried out using dead offspring from a disease resistance challenge test. Second, AFLP genotyping among survivors followed by a Mendelian segregation test was performed. Third, within-family survival analyses using all offspring were developed and applied to significant TDT markers with Mendelian inheritance. Maximum-likelihood methodology was developed for TDT with dominant markers to exploit linkage disequilibrium within families. The strategy was tested with two full-sib families of Atlantic salmon sired by the same male and consisting of 79 offspring in total. All dead offspring from the two families were typed for 64 primer combinations, resulting in 340 scored markers. There were 26 significant results out of 401 TDTs using dead offspring. In the second stage, only 17 marker families showed Mendelian segregation and were tested in survival analysis. A permutation test was performed for all survival analyses to compute experimentwise P-values. Two markers, aaccac356 and agccta150, were significant at P < 0.05 when accounting for multiple testing in the survival analyses. The proposed strategy might be more powerful than current mapping strategies because it reduces the number of tests to be performed in the last testing stage.

Animals↗

PubMed1997

Approaches to improve epidemiological studies of diabetic neuropathy: insights from the Rochester Diabetic Neuropathy Study.

The quality of the epidemiological data on diabetic neuropathies remains poor for a variety of reasons. They include variability in 1) ascertainment of diabetes, 2) the clinical varieties of diabetic patients studied, 3) characterization of neurological dysfunction, 4) abnormal limits for neurological examinations and tests, 5) minimal criteria for neuropathy, 6) correct attribution of nondiabetic neurological disease, 7) correct attribution of type of neuropathy, 8) estimating neuropathy from use of multiple tests, and 9) estimating severity of polyneuropathy. We have tried to remedy these short-comings in the Rochester Diabetic Neuropathy Study (RDNS). It was not possible to adequately characterize and quantitate diabetic polyneuropathies using only one or two clinical or test abnormalities. To estimate severity of diabetic polyneuropathy, the results of the neurological examination and abnormalities of nerve conduction, quantitative sensory tests, and quantitative autonomic tests were combined into a composite score. One begins by scoring a standard test of neurological deficits (impairments) of the lower limbs (NIS[LL]) and adds to this transformed numbers for percentile abnormality of seven good functional tests. This NIS(LL)+7 tests score appears to provide a much more comprehensive and stable numeric score by which to diagnose and grade severity of diabetic polyneuropathy than does the use of individual clinical or test results. This test score should be useful as a measure of change in diabetic polyneuropathy for purposes of medical practice, epidemiology studies, and controlled clinical trials. The staging approach that we introduced previously continues to provide an important measure of overall severity of diabetic polyneuropathy, taking into account both symptoms and impairments.

Cross-Sectional Studies↗

PubMed1979

Correlation between the rosette test with neuraminidase-treated sheep red blood cells and acid phosphatase activity in lymphocytes from patients with lymphoproliferative disease.

In 14 adult patients suffering from lymphoproliferative diseases, the relation between numbers of lymphocytes determined by the rosette test (nSE) with neuraminidase-treated sheep red blood cells and numbers of lymphocytes giving a positive reaction for acid phosphatase was determined. Statistical analysis of multiple test results in the patients (n = 38) showed highly positive correlation between the two markers. A similar positive correlation in the course of cytostatic treatment was observed in selected patients with type T and B cell lymphoma. The results indicate that determination of acid phosphatase activity can serve as an additional marker of T lymphocytes in groups of patients with lymphoproliferative disease.

Acid Phosphatase↗

PubMed1996

Antimicrobial resistance and serotype distribution of Streptococcus pneumoniae strains isolated in southern Taiwan.

The antimicrobial susceptibilities and serotypes of 115 Streptococcus pneumonia strains isolated in southern Taiwan from January 1990 to December 1993 were determined. All isolates were susceptible to cephalothin, cefotaxime, trimethoprim/sulfamethoxazole and vancomycin, and 14 of the isolates were resistant to penicillin G. The oxacillin disk method for presumptive detection of resistance to penicillin had a sensitivity of 85.7% and specificity of 97.0%. Resistance rates were as follows: erythromycin 62.2%, tetracycline 71.3%, clindamycin 46.1% and chloramphenicol 19.1%. Eighty-four percent of the isolates were resistant to one or more of the antibiotic tested. Multiple resistance (to three or more classes of antibiotics) was identified in 40.9% of all the isolates and 100% of penicillin-resistant isolates. The predominant serotypes were: 14 (19.1%), 3 (17.4%), 23 (15.7%), 6 (10.4%), and 15 (6.1%). Serotypes 14 and 63 most commonly caused childhood infections, while serotypes 3 and 23 were frequently encountered in adults. The proportion of coverage in 23-valent pneumococcal polysaccharide vaccine was 92.2%, if vaccine-related serotypes were considered to be cross-protecting. Seven (58%) of 12 typable penicillin-resistant isolates belonged to serotype 23 and two (16.7%) to serotype 6. All isolates of serotype 14, 23, 15 and 19 were resistant to one or more antibiotics. Multiple drug resistance was frequently associated with serotype 23 (31.9%), 14 (23.4%) and 6 (17.0%). Sixty-five percent of isolates of serotype 3 were susceptible to all antibiotics tested. The high level of antimicrobial resistance in S. pneumoniae mandates the continuous surveillance of resistance and the strict control of antibiotic use in Taiwan.

Adult↗

PubMed1986

Quality control aspects of pulmonary function testing in the Multiple Risk Factor Intervention Trial.

Pulmonary function testing was used in MRFIT to monitor the presence of airways disease and to assess changes in pulmonary function over time. The pulmonary function indices that were measured were FEV1, FVC, and MMEF, (FEF25-75). Quality control of technician training, equipment maintenance, data collection, and data measurement were essential to ensure that results, over time and from various clinics, could be compared. Based on the MRFIT experience, it is strongly recommended that centralized training in testing techniques and spirometer maintenance take place before a clinical trial begins, and periodically throughout a trial. Such training, combined with quality control follow-up, should prevent the loss of data due to inadequate spirometer maintenance and invalid testing procedures.

Allied Health Personnel↗