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PubMed1991

Immunoglobulin M (IgM) indirect enzyme-linked immunosorbent assay and the involvement of IgM-rheumatoid factor in the serodiagnosis of BHV-1 infection.

An IgM enzyme-linked immunosorbent assay (IgM-ELISA) for the detection of antibodies to bovine herpesvirus-1 (BHV-1) was developed. Its applicability was examined by serological studies in two calves experimentally infected with virulent BHV-1 over a period of 60 days. IgM antibodies were detected by ELISA on day 6 after infection, and there was an increase in IgG antibodies on day 9. Serum neutralizing (SN) antibodies were detected only on day 13, confirming the higher sensitivity of the ELISAs. A similar study of four calves treated with a commercial inactivated virus vaccine indicated no detectable IgM-ELISA response, and late SN and IgG-ELISA reactivity. Thus IgM-ELISA appears to be of value in assessing recent infection, whereas IgG-ELISA and SN cannot distinguish between infection and vaccination. The possible limitations imposed on the specific IgM-ELISA by the presence of IgM rheumatoid factor (IgM-RF) in bovine serum were examined. IgM-RF levels were determined in bovines of various ages. Elevated values of IgM-RF were found in the sera of older animals; their occurrence may lead to false IgM-positive diagnosis (16%) of BHV-1 infection. This was examined in 113 serum specimens from suspected cases of BHV-1 infection and in 32 bulls at an insemination center. Pretreatment of serum samples with an antibovine IgG serum eliminated false positivity of the IgM-ELISA. It is concluded that IgM-ELISA should be of particular value in the diagnosis of recent infection with BHV-1, mainly in calves.

Animals↗
PubMed1996

Lung cancer rates in carbon-black workers are discordant with predictions from rat bioassay data.

The recent demonstration of lung tumors in rats chronically exposed to airborne carbon-black particles has prompted reevaluation of the carcinogenicity of carbon black. However, accumulating evidence suggests that rat responses to inhaled particles are unique and are mediated by the sequelae to lung overload conditions. To test the predictive value of the rat inhalation bioassay for human lung cancer risk, we examined epidemiologic studies of workers exposed to carbon black during its manufacture or use. Industries in which significant airborne carbon-black exposure has occurred were not associated with increased lung cancer risk. We also predicted the number of occupational lung cancer cases that one would expect in exposed workers, based on the cancer potency of carbon black derived from rat studies. Our quantitative comparison of the tumorigenicity of carbon black predicted from rat studies to the lung cancer rate in carbon-black workers showed a marked discrepancy between the lung cancers predicted and those actually observed. We found that far more lung cancers are predicted from the rat bioassay than can be demonstrated in workers. We determined that it is highly unlikely that this discrepancy is due to chance. We conclude that extrapolating the incidence of lung tumors in rats inhaling inert, insoluble particles, such as carbon black, to humans must be seriously questioned. Using rat inhalation bioassay data for carbon black to estimate lung tumor risk in humans must be seriously questioned unless the mechanisms of the rat's unique response are shown to be relevant to humans.

Administration, Inhalation↗
PubMed2001

Inflammatory and hormonal measures predict neuropsychological functioning in systemic lupus erythematosus and rheumatoid arthritis patients.

Abnormalities of inflammatory and hormonal measures are common in SLE patients. Although cognitive dysfunction has been documented in SLE patients, the biological mechanism of these deficits has not been clarified. The goal of this study was to explore the relationship between inflammatory and hormonal activity and measures of learning, fluency, and attention in systemic lupus erythematosus patients without neuropsychiatric symptoms (non-CNS-SLE), patients with rheumatoid arthritis (RA), and healthy controls (HC). Fifteen non-CNS-SLE patients, 15 RA patients and 15 HC participants similar in age, education, and gender (female) were compared on tests of cognition, depression, and plasma levels of interleukin-6 (IL-6), dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEA-S) and cortisol. Non-CNS-SLE patients demonstrated lower learning and poorer attention. Furthermore, non-CNS-SLE and RA patients had significantly lower levels of DHEA and DHEA-S than HC participants. Hierarchical regression analysis demonstrates that DHEA-S and IL-6 accounts for a unique portion of the variance in subject performance on measures of learning and attention after controlling for depression and corticosteroid treatment. This data highlights the value of hierarchical analyses with covariates, and provides evidence in humans of a relationship between peripheral cytokine levels and cognitive function.

Adult↗
PubMed2000

Fatigue and declines in cognitive functioning in multiple sclerosis.

OBJECTIVE: To determine whether cognitive fatigue, defined as a decline in cognitive performance over a single testing session, could be identified in MS. METHODS: Forty-five individuals with MS and 14 healthy control participants completed a 4-hour session of cognitive testing that involved a baseline neuropsychological battery, a continuous effortful cognitive task (completing mental arithmetic problems administered on a computer), and a repeat neuropsychological battery. Self-report measures of fatigue and affect were completed before each step of the testing session. RESULTS: The pattern of change in cognitive performances over the testing session significantly differed between the MS and control participants. Individuals with MS showed declines on measures of verbal memory and conceptual planning, whereas the control participants showed improvement. Although there were no significant differences between the groups on any of the baseline cognitive measures, the MS participants performed worse than the control subjects on tests of visual memory, verbal memory, and verbal fluency that were repeated following the continuous effortful cognitive task. Both MS and control participants reported increased mental and physical fatigue across the testing session compared with their baseline values. CONCLUSION: Individuals with MS show declines in cognitive performance during a single testing session and fail to show the improvement exemplified by healthy control subjects.

Adult↗
PubMed1985

Predictive value of early maximal exercise test and thallium scintigraphy after successful percutaneous transluminal coronary angioplasty.

Restenosis of the dilated vessel after percutaneous transluminal coronary angioplasty can be detected by non-invasive procedures but their ability to predict later restenosis soon after a successful angioplasty as well as recurrence of angina has not been assessed. A maximal exercise test and myocardial thallium perfusion scintigraphy were, therefore, performed in 91 asymptomatic patients a median of 5 weeks after they had undergone a technically successful angioplasty. Primary success of the procedure was confirmed by the decrease in percentage diameter stenosis from 64(12)% to 30(13)% as measured from the coronary angiograms and in the trans-stenotic pressure gradient (normalised for mean aortic pressure) from 0.61(0.16) to 0.17(0.09). A clinical follow up examination (8.6(4.9) months later) was carried out in all patients and a late coronary angiogram obtained in 77. The thallium perfusion scintigram showing the presence or absence of a reversible defect was highly predictive for restenosis whereas the exercise test was not. The positive predictive value of an abnormal scintigram was 82% compared with 60% for the exercise test (ST segment depression/or angina or both at peak workload). Angina or a new myocardial infarction occurred in 60% of patients with abnormal and in 21% of patients with normal scintigrams.

Adult↗
PubMedDate not supplied

[Estimation of the risk of Alzheimer type dementia based on "Prognostic Questionnaire"].

The aim of undertaken studies was verification of usefulness of "Prognostic Questionnaire" for estimations of risk of Alzheimer type dementia. In support for own base were included 286 persons, which were investigated by scales creating of "Prognostic Questionnaire" in years 1991-1993. From among 286 persons originally classified to renewed study one surrendered 163 persons. Result in investigation MMSE equal or lower from 25 points was base to removal full psychiatric investigations which had in view recognition of Alzheimer type dementia or its exclusion. Possible Alzheimer disease were recognized at 23 persons. Sensitivity and specificity for "Prognostic Questionnaire" obtained for several critical values were marked. The study showed usefulness of joint interpretation of results of several clinical scales creating "Prognostic Questionnaire" for estimations of risk of Alzheimer type dementia.

Aged↗
PubMed1986

Respiratory distress following major trauma. Predictive value of blood coagulation tests.

We have evaluated the use of laboratory parameters to predict the risk of adult respiratory distress syndrome (ARDS) at an early stage after major trauma. Patients with lung contusion were excluded. Five of 29 patients fulfilled our criteria of ARDS, i.e. PaO2/FiO2 less than or equal to 38. They showed lower platelet counts and antiplasmin as well as a tendency to lower antithrombin III, fibrinogen, and plasminogen. These changes indicated activation of the coagulation and fibrinolytic systems by trauma. The most sensitive indicator of ARDS seemed to be the platelet count, although it was also related to blood loss and amount of blood transfused. Hence the platelet count should be considered in relation to blood replacement in the patient with major trauma. Tentative laboratory values are suggested to indicate risk levels of developing ARDS.

Aged↗
PubMed1989

Item reliability of the Milani-Comparetti Motor Development Screening Test.

The purpose of this study was to determine the level of interobserver and test-retest reliability of the Milani-Comparetti Motor Development Screening Test. Sixty healthy children, aged 1 through 16 months, were videotaped during administration of the Milani-Comparetti test. Four pediatric physical therapists independently viewed each videotape and scored the responses. Interobserver reliability was determined by calculation of percentage of agreement and the G statistic between a primary observer and each therapist. Forty-three children were retested within one week by the initial tester to examine test-retest reliability. Test-retest reliability was determined by percentage of agreement of items between the two test sessions and using the Kappa statistic. Interobserver percentage of agreement for the individual items on the Milani-Comparetti test ranged from 79% to 98%. The G statistic was significant for all items indicating the high percentage-of-agreement values were not due merely to chance agreement. Test-retest agreement ranged from 80% to 100%. Using Kappa statistic guidelines, excellent test-retest reliability (K greater than .75) was found for 82% of the test items, with good reliability of the remaining items. Acceptable interobserver and test-retest reliability was found for all items on the Milani-Comparetti test. Use of the Milani-Comparetti test as a clinical screening tool for prediction or follow-up of motor development in children at risk for developmental delays requires further evaluation.

Child Development↗
PubMedDate not supplied

Determination of cut-off positivity values in nasal challenge testing of patients with allergic rhinitis.

Nasal challenge testing with allergen extracts is currently used to diagnose nasal allergy and, to a greater extent, in studies of pathophysiology of allergic rhinitis. The resulting nasal obstruction, measured as nasal airway resistance (NAR), is determined by rhinomanometry (RMM). The aim of this study was to define a cut-off NAR value for a positive response in a nasal allergen challenge test. Forty-two, grass-allergic adult patients and 40 nonallergic adults were challenged out of the grass pollen season under standard conditions with timothy grass extract administered intranasally in doses increasing from 10 to 1500 IU/mL. Inspiratory NAR was determined by computerized anterior active RMM. The cut-off value for a positive test was determined from receiver operating characteristic curves plotted from these data with the LABROC1 computer program. In addition, the subjects' nasal cycle was recorded during the four hours preceding the allergen challenge. The patients' mean NAR value at baseline (0.33 Pa/cc/sec) and when challenged with normal saline solution did not differ from those of the control subjects. The patients, but not the control subjects, experienced typical nasal allergic symptoms when challenged with the grass extract. The control subjects had no symptoms and their NAR did not change significantly when they were challenged with the same extract. All 42 allergic patients had measurable increases in NAR at the 800 IU/mL allergen dose; 19/42 patients had complete obstruction (i.e., NAR unmeasurable) when challenged with the 1500 IU/mL dose. The maximum diagnostic value (= sensitivity + specificity at the discriminator position on the receiver operating characteristic curves) was 1.96 with the 800 IU/mL dose. At that dose, the NAR cut-off value was 0.91 Pa/cc/sec, which was 2.7 times greater than their mean value at baseline. NAR varied less than 1-fold between the maximum and minimum points of the normal nasal cycle in both groups of subjects. An increase of NAR of nearly three-fold during nasal allergen challenge compared to the baseline value determined by computerized anterior active RMM discriminates best patients with allergic rhinitis from nonallergic adults.

Adult↗
PubMed2001

[Biochemical markers of fibrosis in chronic hepatitis and liver cirrhosis of viral origin].

OBJECTIVE: Usefulness of three selected extracellular matrix components as markers of hepatic fibrosis in patients with chronic viral hepatitis and post inflammatory liver cirrhosis. METHODS: 91 patients with chronic HBV or HCV infection were divided into four groups; chronic hepatitis--group O; cirrhosis classes A, B and C (Child-Pugh classification)--groups A, B and C, respectively. The serum levels of: N-terminal peptide of type III procollagen (PIIIP), laminin (LP1) and hyaluronic acid (HA) in these patients were measured using commercial radioimmunological and radiometric tests. RESULTS: The mean values of the investigated markers increased in patients with cirrhosis according to the stage of the disease (thus group A showed the least level while the highest was exhibited in group C). Between all the groups: O, A, B and C, HA was the marker showing the greatest difference. The only marker with a greater mean level in group O than group A, was PIIIP. Substantially higher levels of the investigated markers were found in the patients with HCV than in those with HBV, but only within group A. CONCLUSIONS: 1) The values of the studied markers increased in various degree with the cirrhosis progress. 2) LP1 and HA measurements have particular value in the clinical estimation of cirrhotic advancement. 3) HA measurement may be helpful in differentiating between cirrhosis and chronic hepatitis. 4) The course of hepatic fibrosis may be influenced by the etiological factor as the values of the studied markers are higher in patients with HCV than in patients with HBV, in the early stage of cirrhosis.

Biomarkers↗
PubMed1993

Cerebral glucose metabolism as a predictor of recovery from aphasia in ischemic stroke.

OBJECTIVE: The recovery of language function seen in poststroke aphasia is significantly related to the severity of the initial neurologic deficit. However, a great deal of variability still remains in the improvement that is actually achieved. To detect predictors that will help in explaining this variability, positron emission tomography (PET) and fluorodeoxyglucose F 18 (18-F-fluorodeoxyglucose) were used and the results were analyzed by stepwise regression. DESIGN: Using PET imaging after injection of fluorodeoxyglucose F 18, the regional changes in glucose metabolism in 26 patients at a period of 12 to 18 days following an ischemic stroke involving the left middle cerebral artery were examined. A second PET examination was performed on 17 of our 26 patients who were able to perform speech activation exercises. All patients received an initial and a 4-month follow-up evaluation of language performance. SETTING: During the two PET studies and the first language assessment, the patients were hospitalized in a neurologic clinic. The follow-up evaluation of language performance was performed when the patients were ambulatory. PATIENTS: Twenty-six patients (10 women, 16 men; aged 38 to 77 years; mean +/- SD, 60 +/- 9.2 years) were selected in the study. Their aphasias were of various types and of varying severity ranging from mild impairment to severe global aphasia. MAIN OUTCOME MEASURES: For the stepwise regression analysis of variables, the following variables were analyzed in resting and activation PET to explain residual variance from the first to the second Token Test: regional cerebral metabolic rate for glucose of infarct and mirror region, left and right cerebral and cerebellar hemispheres, left and right Broca's area, left and right Wernicke's area, and left and right temporoparietal cortex. RESULTS: As was expected, early and late Token Tests exhibit a high correlation (.85). The stepwise regression analysis shows that only the left cerebral hemisphere glucose value of the resting PET had significant effect on the residual variance of the Token Test regression. Regional metabolic rates during speech activation had the largest contribution to a significant recovery from aphasia. The infarct area and its corresponding mirror region, the left Broca's area, and the entire left cerebral hemisphere accounted for 80% of the residual variance. CONCLUSIONS: These results emphasize not only the application of PET activation studies in the prediction of a tissue's potential reserve capacity but also the importance of left hemisphere integrity in the recovery of functional language.

Adult↗
PubMed2006

Validity and utility of the Japanese version of the WHO-Five Well-Being Index in the context of detecting suicidal ideation in elderly community residents.

OBJECTIVE: The aim of this study is to evaluate the validity and the utility of the Japanese version of the WHO-Five Well-Being Index (WHO-5-J) in the context of detecting suicidal ideation in elderly community residents. METHODS: A sample of 696 subjects aged 70 years or over who completed a set of questionnaires was examined. RESULTS: Cronbach's alpha was 0.87 and Loevinger's coefficient was 0.64. The total score was significantly correlated with the number of cohabitants, the number of physical illnesses, physical functioning, instrumental activities of daily living, and depressive symptoms. Subjects with suicidal ideation had significantly lower scores on the WHO-5-J. The receiver-operating characteristic curve analysis indicated that the scale significantly discriminated the subjects with suicidal ideation. When combined with the assessment of a lack of perceived social support (PSS), a standard cut-off criterion of "a total score < or = 12 or answering 0 or 1 to any of the five items" more appropriately identified elderly subjects with suicidal ideation: sensitivity = 87%, specificity = 75%, negative predictive value = 99%, and positive predictive value = 10%. CONCLUSIONS: In combination with PSS, the scale has predictive utility to detect suicidal ideation in elderly community residents.

Aged↗
PubMed2006

Predictors of neurocognitive decline after carotid endarterectomy.

OBJECTIVE: Although the incidence of stroke after carotid endarterectomy (CEA) is low (1-3%), approximately 25% of patients experience subtle declines in postoperative neuropsychometric function. No studies have investigated the risk factors for this neurocognitive change. We sought to identify predictors of postoperative neurocognitive dysfunction. METHODS: We enrolled 186 CEA patients, with both symptomatic and asymptomatic stenosis, to undergo a battery of neuropsychometric tests preoperatively and on postoperative Days 1 and 30. Neurocognitive dysfunction was defined as a two standard deviation decline in performance compared with a similarly aged control group of lumbar laminectomy patients. Univariate logistic regression was performed for age, sex, obesity, smoking, symptomatology, diabetes mellitus, hypertension, hypercholesterolemia, use of statin medication, previous myocardial infarction, previous CEA, operative side, duration of surgery, duration of carotid cross-clamp, and weight-adjusted doses of midazolam and fentanyl. Variables achieving univariate P < 0.10 were included in a multivariate analysis. Data is presented as (odds ratio, 95% confidence interval, P-value). RESULTS: Eighteen and 9% of CEA patients were injured on postoperative Days 1 and 30, respectively. Advanced age predicted neurocognitive dysfunction on Days 1 and 30 (1.93 per decade, 1.15-3.25, 0.01; and 2.57 per decade, 1.01-6.51, 0.049, respectively). Additionally, diabetes independently predicted injury on Day 30 (4.26, 1.15-15.79, 0.03). CONCLUSIONS: Advanced age and diabetes predispose to neurocognitive dysfunction after CEA. These results are consistent with risk factors for neurocognitive dysfunction after coronary bypass and major stroke after CEA, supporting an underlying ischemic pathophysiology. Further work is necessary to determine the role these neurocognitive deficits may play in appropriately selecting patients for CEA.

Age Factors↗
PubMedDate not supplied

[Evaluation of epilepsy surgery].

INTRODUCTION: Neuropsychology is a discipline included in the neurosciences which, over the past twenty years, has shown its value in the assessment and rehabilitation of cognitive functions in different disorders. In particular, in epilepsy it has permitted the description of the different factors which affect cognitive deterioration; permitted the establishment of profiles of cognitive deterioration and also the evaluation of the adverse effects of some anti-epileptic drugs on cognition. DEVELOPMENT: In this paper we confirm the value of neuropsychology in an Epilepsy Unit and describe different procedures for evaluation, as well as the cognitive consequences of the surgery of epilepsy.

Anticonvulsants↗
PubMed1995

Plasma growth hormone response to growth hormone-releasing hexapeptide (GH-RP-6) in children with short stature.

Eighteen children with short stature were evaluated for growth hormone (GH) reserve after pharmacological tests and a single iv injection of GH-RP-6. These children were divided into two groups: 10 were diagnosed as having idiopathic GH deficiency by classical stimulation tests (group A) and the remaining 8 (group B) were considered growth-retarded children with normal GH secretion, following conventional stimulation, but reduced endogenous GH secretion. The results were compared with a group of 12 normal children. As a group, patients in group A showed a lower GH response to GH-RP-6, while patients in group B had a similar response as normal controls. However, on an individual basis, a considerable degree of overlapping in responses among the three groups was evident. These data indicate that, on an individual basis, GH-RP-6 testing is not of diagnostic value in children suspected of having idiopathic GH deficiency.

Adolescent↗
PubMed1999

The diagnostic value of computer-assisted primary cervical smear screening: a longitudinal cohort study.

OBJECTIVES: To assess computer-assisted (neural network based) cervical smear screening as a primary tool for the early detection of cervical dysplasia. DESIGN: Longitudinal cohort study. SETTING: Cytology laboratory reviewing cervical smears taken by general practitioners in a mass screening program in the Netherlands. SUBJECTS: 846 women who developed (pre-)neoplasia of the cervix in the seven years after the baseline smear, and 5217 controls. INTERVENTIONS: Cervical smears were evaluated both by conventional light microscopy and with use of the PAPNET Testing System by the same cytotechnologists. MAIN OUTCOME MEASURES: Seven year histological and cytological follow-up results were obtained for all women from a nation-wide pathology database. RESULTS: Conventional screening diagnosed dysplasia or carcinoma in the baseline smears of 458 (54.1%) of the 846 women who were diagnosed with (pre-)neoplasia during follow-up, whereas computer-assisted PAPNET analysis detected such lesions in 462 (54.6%) of these women. In the control population of 5217 (86.0%) women, in whom follow-up revealed no cervical dysplasia, conventional screening gave false positive results in 210 (4.0%) and computer-assisted PAPNET analysis gave false positive results in 207 (4.0%) smears. The areas under the receiver operation curves (AUC) were 80% (95% confidence interval, 78 to 82%) and 79% (95% confidence interval, 77 to 81%) for conventional and PAPNET-assisted screening, respectively. CONCLUSIONS: The PAPNET Testing System has similar diagnostic value as the conventional screening of Pap smears when used for primary screening.

Female↗
PubMed1999

Noninvasive diagnosis in patients with undocumented tachycardias: value of the adenosine test to predict AV nodal reentrant tachycardia.

INTRODUCTION: Patients with symptoms suggestive of paroxysmal supraventricular tachycardia (PSVT) but no tachycardia documentation often undergo diagnostic electrophysiologic study. In dual AV node physiology with AV node reentrant tachycardia (AVNRT), the anterograde fast pathway is more sensitive than the slow pathway to the effects of adenosine. The purpose of the study was to test the hypothesis that adenosine can be used as a bedside test for the diagnosis of dual AV node physiology and hence for AVNRT. METHODS AND RESULTS: During electrophysiologic study, 37 patients without prior documentation but symptoms indicative for PSVT received incremental dosages of adenosine during sinus rhythm until second-degree or greater AV block was observed. Suggestive signs of dual AV node physiology on the surface ECG (sudden jump of PQ interval > or = 50 msec) were found in 13 (76%) of 17 patients with inducible AVNRT but in only 1 (5%) of the remaining patients (P < 0.01). In the AVNRT group, the maximal increase of the PQ interval between two beats was greater (88+/-45 msec) than in the remaining 20 patients (17+/-11 msec) (P < 0.01). CONCLUSION: Careful evaluation of surface ECG during administration of adenosine helps to identify patients prone to AVNRT. The adenosine test is a valuable noninvasive adjunct in patients with undocumented palpitations suggestive of PSVT.

Adenosine↗