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PubMedDate not supplied

The structure and structural effects of VA rehabilitation bedservice care for stroke.

The purpose of this study was to: 1) examine the variation in organizational structure within rehabilitation bed-service units (RBU) in the Veterans Health Administration (VHA), and 2) evaluate the effects of RBU and parent hospital structure on stroke rehabilitation outcomes. Two VHA-wide surveys of acute and rehabilitation services for stroke were linked with 2 y of VHA rehabilitation outcomes for stroke patients. A random effects mixed model was used to adjust for patient level covariates, control for unique site effects, and test for facility level structural effects. After adjusting for patient covariates, four structural variables were associated with length of stay or patient functional gain. These results indicate that rehabilitation structure is important to rehabilitation outcome. The individual variables identified in this study, namely, diverse multidisciplinary staff, expert physician leadership, staff participation in team care, and richer rehabilitation equipment resources, may represent the distinct aspects of a successful, comprehensive rehabilitation unit.

Adult↗
PubMed1980

Individual changes of DNA catabolite excretion in the course of antitumor therapy of Hodgkin's disease.

In patients with morbus Hodgkin, treated primarily by the actino- and chemotherapy, the excretion was followed of DNA catabolites (deoxycytidine, deoxyuridine, thymidine and their sum) in the course of the therapy. The dynamics was studied of changes in the time interval of interest and attention was paid to its relation to the clinical and histological type of disease and to the successful character of the therapy defined by reaching a complete remission. The group of patients as a whole was characterized by an increased excretion of catabolites in the time interval of interest. No dependence was demonstrated between the catabolite excretion and extent of the disease similarly as between the excretion and successful character of the therapy. The dynamics of the changes in the time intervals of interest was neither remarkably nor continuously increased or decreased. The test of the excretion of pyrimidine deoxyribonucleosides possesses sufficient sensitivity for demonstrating laws in relation to the therapy during group evaluation. With respect to individual variability of values of particular patients and to the absence of the relations mentioned above the test is not suitable to indicate the individual response to the anticancer therapy.

Cyclophosphamide↗
PubMedDate not supplied

[Verapamil binding with the blood erythrocytes and cardiac output in myocardial infarct patients].

In 14 patients with myocardial infarction the degree of verapamil binding with blood erythrocytes after a single oral administration (80 mg/kg) and the dependence pharmacological effect, the minute heart output (+ % MOC), on verapamil content in plasma and erythrocytes were studied. Intraindividual variability of verapamil distribution coefficients between erythrocytes and plasma (RBC/Ptot) is 9.7 +/- 2,3%, and it differs reliably from values of inter-individual variability of this index (33.7 +/- 3.3%).

Adult↗
PubMed1989

Variability of urine albumin excretion in normal and diabetic children.

The variability of urine albumin excretion (UAE) was studied in normal and diabetic children and, in addition, the best method of expressing the data was investigated. In 39 timed overnight urine samples from diabetic children, the urine albumin creatinine clearance ratio (CA/CC) was compared with the urine albumin creatinine concentration ratio (UA/UC), the urine albumin excretion rate (UAER) and the urine albumin concentration (UA). UA/UC predicted CA/CC (r = 0.95) better than either UAER (r = 0.83, P less than 0.02) or UA (r = 0.90), 0.1 greater than P greater than 0.05). The within-individual and the between-individual variability in overnight UA/UC in 171 urine samples from 73 normal children was compared with that of 406 urine samples from 119 diabetic children, using a "random effects type 2 nested analysis of variance" model. Geometric mean (range) UA/UC (mg/mmol) in diabetic children, 0.55 (0.04-6.90), was greater than in normal children, 0.33 (0.05-2.10, P less than 0.01), and 18% of diabetics had a value of UA/UC above the normal range. Within-individual variance was the same in normals (0.12) and diabetics (0.12), but between-individual variance in diabetics (0.18) was much greater than in normals (0.03). These data show that within-individual observations for both normals and diabetics are highly but equally variable. Furthermore, from these data, it is possible to infer that a minimum of five estimations are necessary per individual to estimate the true mean value of urine albumin excretion with reasonable confidence.

Adolescent↗
PubMed1997

Radiosensitivity of different aged human lymphocytes following electron irradiation in vitro.

Cytochalasin B-blocking micronucleus test and chromosomal aberration analysis were used in this study to estimate the yield of individual variability in radiation response of different aged human lymphocytes. Both analyses were performed in three groups of adults, aged 18-65 years, on two sampling times, following irradiation by therapeutical dose of 2 Gy e- in vitro. No statistically significant difference in the induced yield of exchange aberrations between individuals under consideration was found. The yield of total aberration data showed greater variability and was statistically significant in the oldest group against two other adult groups. Regarding to fixation times no statistically significant differences in the induced yield of chromosomal aberrations (exchanges as well as total aberrations) were observed. The study has shown a slight increase in spontaneously occurring micronuclei with age. Almost equal mean number of radiation induced micronuclei was observed in the groups of adults aged 18-20 and 45-55 years. The highest mean number was observed in the oldest group. Evident variation in number of radiation induced micronuclei among individuals from the same age group was observed. The results of micronuclei assay for all individuals under consideration show statistically significant difference in the yield of radiation-induced micronuclei regarding the second fixation time. This study has shown that cytochalasin-B blocking micronucleus test is more sensitive assay than chromosomal aberration analysis for the estimation of individual radiosensitivity.

Adolescent↗
PubMedDate not supplied

Stability and variability of locomotor responses of laboratory rodents. II. Native exploratory and basal locomotor activity of Wistar rats.

The exploratory and basal locomotor activities were tested in four groups of Wistar rats twice, at a 4 day interval, to investigate the variability of responses and their changes on repetition of the test. The locomotor activity of rats was much lower than that of mice, particularly when the basal locomotor activity is concerned, but the individual variability was much higher. The exploratory activity declined significantly on the repeated testing. However, there was a good correlation between the individual exploratory activity in two consecutive tests, which suggests that preselection in the rat may be useful.

Animals↗
PubMed1996

An assessment of nonconvulsive seizures in the intensive care unit using continuous EEG monitoring: an investigation of variables associated with mortality.

Of 49 patients with nonconvulsive seizures studied with continuous EEG monitoring, the overall mortality was 33% (16/49). Of the 23 patients with nonconvulsive status epilepticus (NCSE), 13 died (mortality 57%). Individual variables significantly associated with mortality were age, presence of NCSE, seizure duration, hospital and NICU length of stay, and delay to diagnosis and etiology (acute illness versus remote symptomatic). With multivariate logistic regression, only seizure duration (p = 0.0057, OR = 1.131/hour) and delay to diagnosis (p = 0.0351, OR = 1.039/hour) were associated with increased mortality. Acute symptomatic cases could not be adequately classified as either absence, simple, or complex partial status epilepticus when the impairment of consciousness arose form the initial illness. Current classifications of status epilepticus are inadequate for such cases.

Adult↗
PubMed1991

Calcium content of serum and myocardium in vitamin D-induced cardionecrosis.

The dynamics of calcium content alterations in serum and heart muscle in relation to vitamin D-induced cardionecrosis was the aim of the experiment performed on female Wistar rats killed at different times after one or two intraoral doses of 100,000 IU of vitamin D. Calcium concentration in the serum showed great individual variability, although the mean value was significantly elevated after 22 h following one dose and after 2 h following two doses of vitamin D. In the heart muscle the mean calcium content increased 72 h after one dose and 24 h after two doses of 100,000 IU of calciol, but in individual rats the increase of Ca concentration was observed as early as 30 h after one dose, in some it was normal even after 144 h of two doses and varied between individual rats 20-30-fold. The degree of cardionecrosis showed great variability among rats treated with the same dose of calciol and at the same phase of the experiment. Cardionecrosis was always preceded by great accumulation of calcium in the heart muscle and its extent was in direct correlation to the amount of calcium in the tissue, regardless of the dose of calciol and phase of the experiment.

Administration, Oral↗
PubMed1987

Psychophysiological assessments in a repeated-measurement design extending over a one-year interval: trends and stability.

Intra-individual variability in psychophysiological parameters of activation processes can be attributed to functional fluctuation and/or error of measurement. A repeated measurement design at intervals of about three weeks, three months and one-year duration, in which a laboratory-field comparison was made with respect to predictability of individual differences, provided data on a broad spectrum of physiological and psychological variables measured under various conditions. We investigated the reproducibility of commonly used laboratory measures in a sample of male students of physical education (N = 58). Results indicate that a hypothetical general trend component accounts for less than 10 percent of the total variance in a two-factorial ANOVA (Subjects X Replications). Stability coefficients based on raw scores (rest and strain scores) are relatively higher than those based on change scores. Stability of heart rate, pulse wave velocity, respiration rate during rest, mental arithmetic and cold pressor test and cardiovascular and respiratory parameters during ergometer exercise and 1000m run exceed the stability of blood pressure, parameters from impedance cardiography, eye blink and electrodermal activity during the respective laboratory conditions. The implications of such descriptive studies for the planning and evaluation of longitudinal studies and for selection of parameters depicting habitual dispositions in differential psychophysiological research are indicated.

Adult↗
PubMed2006

Increased prepulse inhibition of the acoustic startle response is associated with better strategy formation and execution times in healthy males.

Prepulse inhibition (PPI) refers to the attenuation of the amplitude of the startle reflex in response to sudden intense stimuli (pulse) if preceded by a weaker sensory stimulus (prepulse). PPI reflects the ability to filter out irrelevant information in the early stages of processing so that attention can be directed to more salient environmental features. Inhibition at this early stage of information processing appears modulated by the prefrontal cortex in a "top-down" fashion and this may account for the normal inter-individual variability in PPI and in cognitive performance. PPI data were calculated from 82 healthy male subjects who were also tested in problem solving (Stockings of Cambridge; SoC), spatial working memory (SWM) and 5-choice reaction time (RT) tests from the Cambridge Neuropsychological Test Automated Battery. Correlations between PPI scores and cognitive test variables were examined. In addition PPI scores were divided in quartiles which were used as grouping factors in examining cognitive test performance. Compared to individuals in the lowest quartile those in the highest had (a) shorter execution but not reaction times on the 5-choice RT, (b) shorter subsequent but not initial thinking times in the SoC where they also solved more problems correctly with the minimum number of moves, and (c) better strategy but not errors scores in the SWM. Our findings suggest that greater PPI is associated with superior abilities in strategy formation and execution times. We suggest that this is due to more efficient early information processing.

Acoustic Stimulation↗
PubMedDate not supplied

Impacts of illness and disability on the well-being of older people.

This study examined ways in which aspects of activity may mediate relationships between physical illness and well-being among older people. Data were from the Health Status of Older People survey of 1000 people aged 65 and over who lived in the community in Melbourne, Australia. After controlling for gender, marital status, and perceived social support, multivariate analyses showed that the major impacts of illness and pain were through their effects on activity limitations, which in turn were related to lowered well-being. Limitations with instrumental activities were associated most with lower positive affect, while perceived activity limitations due to major illness had more impact on increased negative affect and depressive symptoms. However, most older people with major illness still scored highly on well-being, and there was individual variability in well-being. Research on the impacts of illness needs to take more account of impacts on daily living and differences in individual interpretation of illness and disability. Health promotion and treatment can enhance the well-being of older people by maintaining and regaining independence and activity when individuals experience major illness.

Activities of Daily Living↗
PubMed2004

Immunogenetic susceptibility of atherosclerotic stroke: implications on current and future treatment of vascular inflammation.

The understanding of the pathophysiology governing atherosclerosis supports a prominent role for inflammation pathways in plaque initiation and progression that result in stroke and myocardial infarction. Elevated levels of inflammatory markers in the blood, such as C-reactive protein and CD40 ligand/CD40, in concert with increased expression of adhesion molecules, chemokines, cytokines, matrix metalloproteinases (MMP), and inflammatory cells in the plaque, characterize the symptomatic atherothrombotic state. Advances in predictive capabilities of vascular events using a number of these biomarkers are beginning to remodel our clinical practice in the use of medications such as statins and angiotensin receptor blockers for stroke prevention. Although the general inflammatory features of atherosclerosis are becoming widely recognized, factors resulting in individual variability in plaque formation and instability remain poorly defined. Emerging literature points toward several acquired and innate susceptibility factors in the immune pathways that may provide insight into why many plaques rapidly evolve from a "stable" to an "unstable" or symptomatic state. First, exposure of plaque memory T-lymphocytes to infectious or endogenous antigens may result in rapid clonal expansion of T-cell variable beta chain subtypes and stimulate macrophages to release MMPs, causing plaque destabilization. The effects of infectious agents can further be influenced by an individual's major histocompatibility complex class II molecule profiles, which can affect susceptibility to specific organisms. Second, functional polymorphisms of genes that regulate the immune pathway can predispose patients to a more robust inflammatory expression after risk factor exposure. Identification of a susceptibility gene profile and immunologic mediators that promote T-cell activation provides a unique opportunity for early identification of stroke risk and targets for future therapy.

Angiotensin II Type 1 Receptor Blockers↗
PubMed2003

Predicting job insecurity via moderating influence of individual powerlessness.

While job insecurity has been extensively studied since Greenhalgh and Rosenblatt called attention to it in 1984, this paper examined why some individuals respond to the antecedents of job insecurity with increased job insecurity while others do not. This research sought to assess whether a moderator variable, individual powerlessness, might offer explanatory information on why people experience job insecurity. Moderated multiple regression analysis on a sample of 276 managers using Caplan, Cobb, French, Van Harrison, and Pinneau's 1975 Job Insecurity scale and Ashford, Lee, and Bobko's 1989 Powerlessness scale, suggested that an individual's powerlessness moderates the effect of antecedents on measured job insecurity. An interaction was found for subjects scoring high on powerlessness and not for those scoring low as hypothesized.

Adult↗
PubMed2003

[Does grapefruit juice increase the bioavailability of orally administered sex steroids?].

OBJECTIVE: To verify if and to which extent the interaction with grapefruit juice can increase bioavailability of orally administered sexual steroids. DESIGN: Pilot pharmacokinetics study. SETTING: Department of Obstetrics and Gynecology and Institute of Pharmacology, Medical Faculty, Palacký University, Olomouc; Department of Nuclear Medicine, University Hospital, Olomouc. METHODS: 2 mg of estradiol valerate and 100 mg of micronized progesterone were given to eight healthy postmenopausal volunteers. Blood samples were collected at time 0, 2, 3, 5 and 24 hours after tablets application. The same trial was repeated a week later but tablets were swallowed with 200 ml of grapefruit juice. Serum levels of estradiol and progesterone were measured by RIA. Results were statistically evaluated using the Wilcoxon's nonparametric paired test. RESULTS: Though grapefruit juice on average slightly increased serum levels of estradiol (E2) and progesterone, this increase reached statistical significance only for the E2 level 24 hours after application of tablets. The mean area under curve (AUC) of estradiol rose significantly to 117%. The even greater increase in the mean AUC of progesterone (to 125%) was not statistically significant because of marked individual variability of response. CONCLUSIONS: Our results suggest that grapefruit juice may increase bioavailability of orally administered estradiol and progesterone. The response varies markedly between individuals. This observation may be of some importance also for users of OC and HRT.

Administration, Oral↗
PubMed1988

[Acute and long-term psychological problems following hypoglycemias].

1. Detection of hypoglycaemic episodes is of psychiatric importance with respect to acute therapy, long-term treatment, which includes consideration of changes in specific behaviour patterns, and also forensic questions. 2. All possible therapeutic efforts must be focussed on the avoidance of repeated hypoglycaemic episodes to ensure the prevention of organic psychosyndromes (dementia). 3. The therapeutic proceedings should consider methods of behavioural medicine and behavioural modification too. Such techniques may amplify the traditional medical aspects, especially stressing the significance of compliance, illness-related information, family variables, diet, and bodily exercise (according to Epstein). Methods of behavioural medicine have shown that specific techniques should be applied with care and take individual variability and conditions into account according to single subject methodology. Uncritical application of such techniques is useless.

Acute Disease↗
PubMed2001

Transfer functions as a basis for the verification of models--variability and restraints.

OBJECTIVE: The seat-to-head transfer function of the human body reflects the biodynamic response. Based on measured data, biodynamic models have been proposed to reflect this response. They must satisfy usually the international published mean values of the seat-to-head transfer function. The question arises to what extent mean values reflect individual pattern of biodynamics. METHODS: An experimental study was performed with 39 male subjects sitting on a hard seat without back rest and with supported feet. They were exposed to random whole-body vibration at three intensities with a relaxed and an erect posture. The accelerations in the z-direction were measured at the seat and head. The seat-to-head transfer functions with the associated coherence functions were calculated. RESULTS: The biodynamic response characterised by the maximum of the seat-to-head transmissibility and the frequency of its occurrence is influenced by the posture of the subjects in a dominant way and shows an individual variability of considerable extent. The mean responses suggest a missing effect of vibration intensity, but individually different effects of the intensity were found. Repeated measurements confirmed this result. CONCLUSIONS: The application of a model validated by the comparison with mean values of the transmissibility could cause misleading conclusions, if it is used for the prediction of individual spinal loads. Models prepared for the calculation of individual loads should be validated by a mean individual transmissibility derived from repeated measurements. RELEVANCE: The results illustrate the loss of information by averaging individual transfer functions and the consequence of a limited validity and applicability in occupational health, ergonomics, and design.

Acceleration↗
PubMed1999

Stability and change in older adults' social contact and social support: the Cardiovascular Health Study.

OBJECTIVES: The aim of this study was to examine the degree of individual change in structural indicators of social support (family network contact and close friend network contact) and functional indicators of social support (belonging, appraisal, and tangible support) during late life. METHODS: Using a large population-based sample of older adults, hierarchical linear modeling was applied to examine the extent of change in social contact and support as well as sociodemographic characteristics (age, race, gender, and education) that might explain individual variability in contact and support at baseline and over time. RESULTS: Consistent with predictions, small yet significant increases were observed in belonging support and tangible support. Contrary to predictions, no evidence was found for significant individual change in family network contact, close friend network contact, or appraisal support. Sociodemographic characteristics were more consistent predictors of variability in contact and support at baseline than variability over time. DISCUSSION: The findings of this study add to a growing literature suggesting that late life is not typically characterized by a decline in important social resources.

Age Factors↗
PubMed2003

Role of platelet glycoprotein polymorphisms in cardiovascular diseases.

Atherothrombosis is the leading cause of death in western countries. Major complications of atherothrombotic disease, which are responsible for a large burden of morbidity and mortality, are acute coronary syndromes, ischemic stroke, and peripheral occlusive disease. Plaque rupture, platelet adhesion, aggregation, and thrombosis may lead to unstable angina and may progress to myocardial infarction as well as to ischemic stroke. Platelet membrane glycoprotein receptors mediate crucial reactions in acute thrombosis and chronic processes of atherogenesis. The platelet glycoprotein GP IIb/IIIa, which is the most abundant platelet receptor, also represents the drug target of a novel class of anti-platelet drugs, which includes abciximab, tirofiban, and eptifibatide. The genes encoding the three major platelet glycoprotein receptors (GP Ib/IX/V, GP Ia/IIa, and GP IIb/IIIa) are subject to considerable genetic variability. This paper reviews how polymorphisms in the platelet glycoprotein receptors affect platelet function, susceptibility to atherothrombosis and its major complications including myocardial infarction, stroke, and complications following percutaneous coronary interventions, and individual variability of drug response. Recent data on platelet glycoprotein receptor polymorphisms as modifiers of drug action and as predictors of drug response offer the perspective of individualized drug treatment. Prospective studies will show whether this approach is useful or not. As the data reviewed here show clearly, future clinical trials should routinely take into account genetic susceptibility factors and modifiers, both for study design and for predefined patient stratification.

Alleles↗