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Results for “Predictive Value of Tests”

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PubMed2003

A normative study of a shorter version of Raven's progressive matrices 1938.

A shorter four-set (A, B, C, D) version of Raven's progressive matrices 1938 (PM38) has gained increasing use in neuropsychological assessment. No normative data spanning across a wide age range are, however, available. This study collected norms for the shorter version of PM38, established an inferential cut-off value and derived equivalent scores in a sample of 248 individuals from 20 to 89 years of age, evenly distributed across sex, age and education levels. Results showed significant effects of age and education but no effect of sex on performance. These normative data will complement existing norms for other tests, will increase the wealth of neuropsychological tools for which normative data are available for the Italian population, and may be useful in the early detection of individuals at risk of developing dementia.

Adult↗

PubMed1988

Estimation of Corynebacterium diphtheriae antitoxin in human sera: a comparison of an enzyme-linked immunosorbent assay with the toxin neutralisation test.

Serum samples from 101 individuals were titrated for Corynebacterium diphtheriae antitoxin by an IgG-specific enzyme-linked immunosorbent assay (ELISA) and a neutralisation test in tissue culture (TC). In some of the sera, the concentrations of antitoxin determined by the two assays were different; antitoxin values in these sera were titrated again by neutralisation tests in guinea pigs (GNT). Antitoxin concentrations of greater than 0.01 IU/ml by GNT partly corresponded to values obtained in both ELISA and TC. Only the values from TC agreed with lower GNT results. Heat inactivation of sera was investigated and rejected as a possible reason for the discrepancy in the results. ELISA can be used to detect levels of less than 0.1 IU/ml, although the accuracy below 0.01 IU/ml, often considered a protective level, is questionable. At higher levels ELISA was reproducible for the titration of diphtheria antitoxin in human sera and offers a useful alternative to both in-vivo assays and TC.

Animals↗

PubMed1997

Positron emission tomography and magnetic resonance imaging for cerebral involvement in patients with systemic lupus erythematosus.

Central nervous system (CNS) involvement in systemic lupus erythematosus (SLE) remains difficult to diagnose, particularly since structural abnormalities may not be revealed by magnetic resonance imaging (MRI). Glucose utilisation was measured by positron emission tomography (PET) in 35 SLE patients to detect signs of CNS involvement. The patients were examined by a standardised neurological examination, a battery of tests to evaluate neuropsychological performance and MRI. Antineuronal antibodies were determined to investigate their putative role in CNS involvement in SLE. Twenty patients had distinct neurological (17) and/or psychiatric (3) symptoms. Ten patients had pronounced cognitive impairment. Neurological and cognitive deficits were thus found to be unrelated disorders in SLE. Global glucose utilisation of SLE patients did not differ significantly from that of normal controls, nor were differences found between SLE patients with or without neurological or cognitive abnormalities. On MRI of the brain, the number and size of white matter lesions correlated with the presence of neurological deficits but were unrelated to the severity of cognitive impairment. Within the normal range, lower global glucose utilisation tended towards lower values with increasing number and size of white matter lesions. Patients with lesions larger than 8 mm also showed distinctly increased IgG anticardiolipin antibody titres, whereas measuring antineuronal antibodies did not reveal any relation to the variables investigated. We conclude that the demonstration of CNS lesions by MRI can contribute confirmatory evidence for CNS involvement in SLE, but PET or the presence of antineuronal antibodies adds little if any information beyond that obtained by clinical examination, neuropsychological testing, and MRI.

Adult↗

PubMed2003

Cognitive deficits and social functioning in schizophrenia: a clinical perspective.

Impaired social functioning is one of the diagnostic features of schizophrenia. Cognitive functioning is also often impaired in several domains. Meta-analysis has shown a predictive value of cognition for a variety of domains related to social functioning (Green, Kern, Braff, & Mintz, 2000). The significance of these findings for clinical practice has remained largely uninvestigated, however, and is therefore taken up here. We investigated verbal memory, attention and executive functioning in 52 schizophrenia patients. Social functioning was assessed for different types of social roles. The percentages of cognitive and social impairments in our group were assessed according to clinical principles, normally used to judge an individual patient. A possible predictive relationship between cognition and social functioning was studied on the basis of these clinical criteria. A large proportion of patients showed impairments in both cognitive functioning and social functioning. However, the clinical method resulted in a successful prediction of social functioning in only 21-69% of the cases. Social functioning and cognitive functioning were impaired in a large proportion of patients, but were largely independent from each other. Since relationships between cognition and social functioning are weak, assessment procedures are inconsistent and possibly not optimally adjusted to the psychiatric population, the clinical relevance of cognitive testing in order to predict social functioning is as yet questionable.

Adolescent↗

PubMed2002

Event-related evoked potential P300 in frontotemporal dementia.

There are no studies on event-related cognitive potentials in frontotemporal dementia (FTD). In order to evaluate the aptitude and usefulness of the event-related P300 potential in this disease, we prospectively examined 60 cases: 11 patients with FTD diagnosed according to the Lund and Manchester criteria and Neary consensus criteria, 33 patients with a probable Alzheimer's disease diagnosis following NINCDS-ADRDA criteria, and 16 normal controls. P300 latency, amplitude and reaction time were recorded using an auditory oddball paradigm. In this sample, P300 potential could be reliably performed by 10/11 FTD patients, notwithstanding their language or executive function deficiencies. The FTD group P300 mean latency was midway between the normal controls and the Alzheimer's disease group (ANOVA F(2, 74199) = 16.5; p = 0.00003). The latency range of the FTD patients were within normal values (average plus 1.96 standard deviation of the values of the control group), except for one case with a latency of 448 ms. Post hoc Newman-Keuls analysis showed that the P300 latencies of the control and FTD groups did not differ significantly (p = 0.15) and that the Alzheimer's disease group had a delayed P300 latency that differed significantly from that of the FTD (p = 0.002) and control group (p = 0.0002). However, there was overlapping in P300 latency values of the three groups. Despite these differences in latencies, the reaction time was significantly increased in the FTD and the Alzheimer's disease groups. These findings indicate that the P300 potential is less affected in patients with FTD than those with Alzheimer's disease. This fact could aid in FTD diagnosis, differential diagnosis with Alzheimer's disease and possibly its clinical management.

Aged↗

PubMed2004

Predictor of cognitive deterioration in elderly subjects by auditory-evoked magnetic signal using magnetoencephalography.

Recent development of auditory-evoked magnetoencephalography (A-MEG) made it possible to measure interhemispheric neural conduction time (INCT) of auditory impulses. We estimated INCT with A-MEG and cognitive function with mini-mental state examination (MMSE) in 85 elderly patients with chronic dizziness (CD) and found that INCT was negatively correlated with MMSE scores (p<0.001). In 11 of 85 patients whose MMSE scores were within the normal range, A-MEG and MMSE were repeated for the subsequent 4 years to find longitudinal changes in INCT and cognitive function. The 11 patients were divided into two groups according to the baseline INCT values, such as Group A with normal INCT (n=7) and Group B with abnormally prolonged INCT (n=4). In Group A, INCT and MMSE scores remained within the normal range throughout the 4-year period. In Group B, INCT showed the tendency towards progressive prolongation during the follow-up period, and MMSE scores decreased to abnormally low levels at the third or fourth follow-up year in all the patients. The present results suggest that rapid neural interaction of both cerebral hemispheres is needed to maintain normal cognitive function. Abnormal INCT prolongation in elderly subjects suggests subclinical cortical network dysfunction and may predict the future development of cognitive deterioration.

Acoustic Stimulation↗

PubMed1993

An evaluation of an intradermal test for the diagnosis of bovine herpesvirus type 1 (BHV-1) infection in cattle.

An intradermal (ID) test (a delayed-type hypersensitivity test) was used for the diagnosis of BHV-1 infection in cattle. A threshold value for the test positive results was established based on the analysis of the agreement between the results of ID test and those of virus neutralization (VN24) assay. Linear regression analysis revealed no correlation between the intensity of the skin reaction (expressed as an increase in skin-fold thickness) and the VN24 antibody titre. The sensitivity and specificity of the ID test compared to VN24 one, were 86.6% and 98.3% respectively. Of the 487 cattle with an age of over 6 months, 25 (5.1%) reacted discordantly by ID and VN24 tests, i.e. 19 seropositive animals expressed little or no skin reaction, whereas 6 seronegative individuals were positive by ID. Neither of the calves, with passively acquired antibodies in contrast to experimentally infected ones, showed distinctive skin reaction.

Animals↗

PubMed1998

Objective assessment of nickel sulfate patch test reactions with laser Doppler perfusion imaging.

The laser Doppler perfusion scanning technique was used to assess the superficial blood flow of nickel sulfate hexahydrate patch test reactions. There was good agreement between laser Doppler and visual assessments when the highest assessment values of reactions were studied. Earlier detection of reactions was possible with the laser technique. There was great inter-individual variance in perfusion between identically tested patients. 4 patients were visually negative when a TRUE Test patch test dose of 0.20 mg/cm2 was applied for 48 h and the test area read 4x up to 168 h. These 4 showed a dose-related increase in perfusion and visually positive reactions using longer application times. The instrument allowed a dose reduction not possible for visual assessments. Reading transparent patches in contact with the skin through transparent semi-occlusive plastic foil or through windows in the tape strip over the patches, allowed us to detect perfusion at 48 h, where a longer application would have been needed using tape and visual assessments.

Adult↗

PubMed2001

Correlations between clinical findings and magnetization transfer imaging metrics of tissue damage in individuals with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy.

BACKGROUND AND PURPOSE: We obtained magnetization transfer imaging (MTI) scans from individuals with cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) (1) to investigate the presence, extent, and nature of pathology in white and gray matter outside proton density (PD)-visible lesions; (2) to quantify the degree of tissue damage occurring in lesions seen on PD-weighted scans; and (3) to correlate MTI-derived measures of disease burden with age, physical disability, and cognitive performance. METHODS: Dual-echo, T1-weighted, and MTI scans of the brain were obtained from 33 individuals with CADASIL and 12 control subjects. Magnetization transfer ratio (MTR) values from PD-visible lesions, normal-appearing white matter (NAWM), and normal-appearing gray matter (NAGM) were measured. Histograms of MTR from the whole brain and normal-appearing brain tissue were also produced. RESULTS: All MTR values from NAWM and NAGM regions studied were significantly lower for individuals with CADASIL than for control subjects, with the exception of those obtained from the NAWM of the infratentorial structures and the NAGM of the occipital cortex. The average MTR from PD lesions in individuals with CADASIL was significantly lower than that from all the NAWM regions. Average MTR and peak location from whole-brain and normal-appearing brain tissue histograms were significantly lower for individuals with CADASIL than for control subjects. MTR values from NAWM were strongly correlated with the extent of macroscopic lesions and their average MTR. Apart from NAGM, average MTR from all other tissues studied significantly decreased with increasing age, physical disability, and cognitive impairment. CONCLUSIONS: PD lesions of individuals with CADASIL have variable degrees of tissue damage. Brain tissue outside PD abnormalities is also damaged. This study suggests that the extent and the severity of the brain tissue damage are critical factors in determining clinical status in CADASIL.

Age Factors↗

PubMed2000

[MR-cholangiography in patients suspected with choledochus calculi].

To test a new non-invasive imaging method, magnetic resonance cholangiography (MRCP), we compared MRCP with intraoperative cholangiography (IOC) or endoscopic retrograde cholangiography (ERC). In 55 patients with 11 common bile duct stones MRCP identified all 11 stones and incorrectly found stones in seven additional patients. Predictive value of positive test was 61%, predictive value of negative test was 100%. As a consequence of MRCP, ERC or IOC can be avoided in 67% of the patients.

Adult↗

PubMed1993

[Detection of endotoxin in plasma: specificity and value for development and prognosis of infection].

A number of problems may be involved in the detection of endotoxin in plasma of patients using LAL (Limulus amebocyte lysate). When collecting blood or processing samples, contamination with endotoxin or its adsorption to material must be avoided. In our laboratory a kinetic LAL microtiter assay was developed that takes into account plasma-related interferences with the LAL endotoxin reaction by performing an internal standardization in each sample. Negative results do not absolutely exclude the involvement of endotoxins in the underlying disease. High levels of endotoxins do not necessarily reflect the severeness of the clinical status of the patient. Due to nonendotoxin-specific reactions with some complete lysates, false-positive levels may result, e.g., following immunoglobulin therapy. In spite of these limitations, the LAL test remains a valuable tool in the evaluation of gram-negative infections.

Endotoxins↗

PubMed1989

A blocking ELISA for the detection of specific antibodies to bovine respiratory syncytial virus.

A blocking enzyme-linked immunosorbent assay (ELISA) has been adapted to detect specific antibodies in bovine sera to respiratory syncytial virus using a horseradish peroxidase-labeled monoclonal antibody to the fusion protein of the virus. This assay plus an indirect blocking ELISA and indirect ELISA were used to detect antibodies to the bovine respiratory syncytial virus (BRSV) in 159 field-origin bovine sera. Results of these assays were compared with serum antibody titers measured by the serum neutralization (SN) test. Over a 56-day period, the mean neutralization titers and the mean delta absorbance values for the blocking ELISA, on the same sera, showed similar declines. However, the calculated correlation coefficients between mean SN titer and mean absorbance value for the blocking ELISA of the individual sera ranged from -0.2 to -0.5 depending on the source of sera. Similar values were obtained whether using crude or purified viral antigen in the assays. Corresponding calculated correlation coefficients were generally higher for the indirect blocking ELISA or indirect ELISA than for the blocking ELISA. The blocking ELISA was between 70 and 64% as sensitive as the serum neutralization test with a specificity of 100 or 90% using the crude and purified viral antigen, respectively. The indirect blocking ELISA and indirect ELISA had similar calculated sensitivities and specificities. The blocking ELISA was faster to run than either of the other ELISA's or the neutralization test. Further, nonspecific background absorbance was obviated because the blocking ELISA detects antibodies to 1 specific viral protein, the fusion protein. These studies suggest that the blocking ELISA should be useful as a serological test for BRSV antibodies.

Animals↗

PubMed2003

Topoisomerase II alpha as a marker predicting the efficacy of anthracyclines in breast cancer: are we at the end of the beginning?

This article attempts to provide the reader with a complete overview of topoisomerase (topo) II alpha as a marker for predicting the efficacy of anthracyclines in patients with breast cancer. In the first section of this article, in vitro data supporting the predictive value of topo II alpha are reviewed. Interestingly, these data suggest that the interaction between HER2 and anthracycline efficacy, which has been hypothesized in several clinical studies performed in the past decade, might depend on the concomitant topo II alpha status. Molecular pathology studies further reinforce the concept that HER2 might not be directly involved in the prediction of response to anthracyclines. They report that topo II alpha gene amplification can be found in 25%-40% of HER2/neu-amplified tumors, while no topo II gene amplification is detected in the absence of HER2/neu gene amplification. In the second part of this article, a series of clinical studies are reviewed and interpreted. These studies have attempted to correlate topo II alpha status with anthracycline efficacy in the adjuvant, neoadjuvant, and metastatic settings. All of the studies evaluating the topo II alpha gene suggest that gene amplification might be associated with an increased efficacy of anthracyclines, and some of the studies evaluating topo II alpha protein find that protein overexpression might correlate with an increased sensitivity to these compounds. Despite these findings, however, the reported studies do not provide the proof of principle needed to authorize the use of topo II alpha as a predictive marker for standard practice. A new generation of research is currently testing the predictive value of topo II alpha. It is hoped that these projects, which are described in the last section of the article, will clarify the role of topo IIa in the prediction of response to anthracyclines.

Anthracyclines↗

PubMed2001

Development of a latex agglutination test for rapid identification of Escherichia coli.

Escherichia coli, one of the most important human pathogens, is usually identified by a battery of biochemical tests that require overnight incubation. For rapid identification of Escherichia coli, a latex agglutination test (LAT) was developed. Rabbits were immunized with cell-surface antigens extracted from Escherichia coli CCRC 15481 with 4 M urea, and the affinity-purified antibodies were used to coat latex particles for the identification of the bacterium. The following gram-negative bacteria were used to evaluate the LAT: Escherichia coli (n = 761), Enterobacteriaceae other than Escherichia coli (n = 632), Aeromonas spp. (n = 21), Pseudomonas spp. (n = 75), Vibrio spp. (n = 18), and other bacteria (n = 64). The LAT had a sensitivity and specificity of 99.2 and 93.3%, respectively. If the LAT was used in conjunction with the tests of indole production or lactose fermentation, the specificity values for the identification of Escherichia coli increased from 93.3 to 98.8 and 98.7%, respectively. If the LAT, indole production, and lactose fermentation were used together for the identification of Escherichia coli, the sensitivity and specificity were 94 and 99.7%, respectively. Lactose fermentation could be detected by observing the colonies grown on selective media (e.g. MacConkey agar), and indole production could be analyzed simply by the spot indole test. Strains producing negative reactions (i.e. not identified as Escherichia coli) should be processed by the conventional procedures for identification. The present protocol integrating the LAT, indole production, and lactose fermentation for the identification of Escherichia coli offers considerable savings of time, manpower, and cost.

Animals↗

PubMed2002

Monitoring disease progression in CADASIL with diffusion magnetic resonance imaging: a study with whole brain histogram analysis.

BACKGROUND AND PURPOSE: In cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), a large increase in water diffusion has been found both inside and outside the cerebral lesions as detected on conventional MRI. The aim of the present study was to assess the sensitivity of diffusion tensor imaging for monitoring the progression of cerebral tissue damage during the course of CADASIL. METHODS: With the use of diffusion tensor imaging, whole brain trace of the diffusion tensor [Trace(D)] histograms were obtained in 22 CADASIL patients and 12 age-matched controls at baseline, in 14 patients after a mean delay of 21 months, and in 5 controls after a mean delay of 29 months. Parameters derived from these histograms (mean value, peak height, and peak location) were analyzed at baseline and during the follow-up. RESULTS: At baseline, all the histogram parameters differed between patients and controls and were found to be significantly correlated with both the Mini-Mental State Examination score and Rankin Scale score in the patient group. The follow-up study showed a decrease in the peak height associated with an increase in the mean value of whole brain Trace(D) histograms in the 14 CADASIL patients scanned twice. The diffusion changes appeared larger in the patients whose Rankin score increased during the study period. CONCLUSIONS: These results suggest that the measurement of water diffusion over time is a sensitive marker for the progression of tissue damage in the brain. Thus, quantitative diffusion MRI can be used to monitor disease progression in CADASIL and possibly in other types of small-vessel brain disorders.

Adult↗

PubMed1993

Value of repeat cervical smears at the time of colposcopic biopsy.

At our institution, gynecologists perform Pap smears not only as an initial screening procedure but also at the time of colposcopy and biopsy. We compared the results of initial Papanicolaou (Pap) smears with those taken at colposcopic biopsy to determine if repeating the Pap smear at the time of colposcopy contributed to patient management. We found that repeat colposcopic smears often agreed with the referral smears and biopsies. When there was disagreement, the colposcopic smear was more often a lower grade than the referral smear and correlated best with the biopsy. Both referral and colposcopic smears underestimated the severity of cervical lesions with the same frequency. We could document only 5/414 (1.2%) colposcopic smears that contributed to patient care.

Biopsy↗

PubMed1988

[Clinical laboratory approach for estimating effective administrative dose of sulbactam/cefoperazone].

Sulbactam/cefoperazone (SBT/CPZ) is a preparation containing CPZ and SBT, an inhibitor of beta-lactamases, at the ratio 1:1. The reliability of the SBT/CPZ disc susceptibility test in estimating approximate values of MICs and the utilization of the test in the evaluation of proper administrative doses were studied using 365 strains of clinical isolates. The antimicrobial activity of SBT/CPZ was stronger than that of CPZ alone. This increase in the antimicrobial activity due to the addition of SBT was well observed in the disc diffusion susceptibility test and MIC values. The MIC80 of SBT/CPZ against Staphylococcus aureus was 12.5 micrograms/ml, while that of CPZ alone was 50 micrograms/ml. MIC80s of SBT/CPZ against Escherichia coli, Pseudomonas aeruginosa, Serratia marcescens and Enterobacter aerogenes were smaller than those of CPZ, and were 0.20, 12.5, 25 and 3.13 micrograms/ml, respectively. However, MIC80s of SBT/CPZ against Staphylococcus epidermidis, Klebsiella pneumoniae, Proteus mirabilis and Proteus vulgaris were not changed compared to those of CPZ alone, and MIC80s were 6.25, 0.20, 0.78, and 0.78 micrograms/ml, respectively. The reliability of the SBT/CPZ disc diffusion susceptibility test in the quantitative estimation of antimicrobial activities was well demonstrated using commercialized 8 mm diameter discs (Showa) and 6 mm diameter discs prepared in this laboratory, both of which contained 30 micrograms of CPZ and 30 micrograms of SBT. These disc susceptibility test results were well correlated with MICs, hence the SBT/CPZ disc susceptibility test should be useful for the estimation of approximate MIC values. To interpret results of the Showa SBT/CPZ disc test, the following 4 category classification was used: (¿) MIC less than or equal to 3 micrograms/ml, (¿ 3 micrograms/ml less than MIC less than or equal to 15 micrograms/ml, (¿15 micrograms/ml less than MIC less than or equal to 60 micrograms/ml, (-) MIC greater than 60 micrograms/ml. In both 6 and 8 mm diameter disc tests, when uniform break points of inhibitory zone diameter were similarly applied to all strains isolated clinically, some strains of S. aureus, E. faecalis, and P. aeruginosa, brought false positive (susceptible) results showing slightly greater inhibitory zone diameters compared to MICs. However, if different break points against P. aeruginosa as indicated in this study were applied and E. faecalis was excluded from the test, excellent results were obtained in the quantitative estimation of MICs. Antimicrobial activities of antibiotic agents have been reported to be reduced by serum protein binding.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacteria↗

PubMed2005

Color-coded diffusion-tensor-imaging of posterior cingulate fiber tracts in mild cognitive impairment.

Different processes like microvascular dysfunction, free radical toxicity, beta-amyloid deposits, and Wallerian degeneration can cause functionally relevant disturbances of cerebral neuronal networks by myelin degeneration. Color-coded diffusion-tensor-imaging (ccDTI) allows the structural identification and quantification of myelinated fiber tracts. Particularly, posterior cingulate fiber tracts, which are regarded as important neuronal substrates of the network representing memory processing can be localized only imprecisely by conventional magnetic resonance imaging techniques. The posterior cingulate bundles were assessed by ccDTI in 17 patients with amnestic mild cognitive impairment (MCI), 25 patients with Alzheimer's dementia (DAT), and 21 age-matched controls. Additionally, DTI values were correlated with memory performance in the delayed verbal recall test. Fractional anisotropy and mean diffusivity differed significantly between MCI and controls, as well as between DAT and controls. Performance in the delayed verbal recall test of the entire study group correlated significantly with posterior cingulate bundle anisotropy and diffusivity. Using ccDTI seems, hence, a favorable strategy to detect and quantify the structural integrity of posterior cingulate white matter in MCI. Alterations of DTI parameters substantiate the involvement of white matter pathology in the development of MCI. Moreover, ccDTI could serve as in vivo method to investigate age and disease-related myelin alterations as potential morphological substrates of cognitive dysfunction.

Aged↗