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PubMedDate not supplied

The use of defenses and physician health care costs: are physician health care costs lower in persons with more adaptive defense profiles?

BACKGROUND: The objective of the present study was to determine if persons who use more adaptive defenses have lower physician health care costs compared to those who use less adaptive defenses. METHODS: We randomly selected 667 persons from the 1995 population-based Nova Scotia Health Survey who completed a videotaped structured interview. Each interview was rated for typical defense use by the Defense-Q. We obtained physician health care costs for 3 months before and after the interview, as well as medical diagnoses and measures of psychological functioning. RESULTS: A more adaptive defense profile significantly predicted lower future physician health care costs. These results were found when controlling for other psychosocial variables, before and after controlling for previous physician health care costs, and when testing only within a physically healthy subsample. Results of secondary analyses showed that a more adaptive defense profile was positively related to a number of psychosocial variables, such as nurse's rating of competence, lack of depressive symptoms, and days at work. CONCLUSIONS: The adaptiveness of a person's defense use in managing affect is important in predicting physician health care costs as well as psychosocial functioning.

Adaptation, Psychological↗
PubMed1998

Negative mood regulation expectancies predict anger among police officers and buffer the effects of job stress.

This study investigated links between occupational stress, negative mood regulation expectancies, coping, anger, and distress. Participants were 56 police officers from two small, urban departments. They filled out the Negative Mood Regulation (NMR) Scale, as well as measures of police stress, coping, anger, and distress. Simultaneous multiple regression analyses revealed that high NMR expectancies predicted subjects' use of adaptive active coping strategies. High NMR Scale scores were also independently associated with lower levels of anger and distress, and anger significantly predicted distress. Results suggest that strong mood regulation expectancies buffer the effects of even high levels of occupational stress. Interventions directed toward raising mood regulation expectancies may help protect officers from the consequences of job stress. Results may also have implications for combat stress.

Adaptation, Psychological↗
PubMed2006

Resilience, misfortune, and mortality: evidence that sense of coherence is a marker of social stress adaptive capacity.

OBJECTIVE: The purpose of this study is to test the hypothesis that sense of coherence (SOC) distinguishes adaptive capacity to adverse event experience. METHODS: A population-based cohort of 20,921 men and women completed a postal assessment of their lifetime experience of specific adverse events and a measure of their SOC. Reports of 111,857 events allowed construction of measures of event impact and adaptation. RESULTS: Those with a weak SOC reported significantly slower adaptation to the adverse effects of their event experiences than those with a strong SOC (P<.0001). During mean follow-up of 6.7 years, 1617 deaths were recorded. A one standard deviation increase in mean adaptation score (representing slower adaptation) was associated with a 6% increase in mortality rate (P=.03) after adjusting for age and sex. Measures of event occurrence and impact were less strongly associated with SOC and were not significantly associated with mortality. CONCLUSION: These results suggest that SOC is a potential marker of an individual's social stress adaptive capacity, which is predictive of mortality.

Adaptation, Psychological↗
PubMed1979

Elbow joint forces in patients with rheumatoid arthritis.

Whilst developing an elbow endoprosthesis, the joint forces were estimated for patients with rheumatoid arthritis. Elbow flexion strength of rheumatoid patients was found to be 45% of normal. Muscle strengths and limb geometry data were found by a dissection technique, which allowed joint forces to be calculated during flexion, extension and abduction efforts. Forces up to 2.4 kN were predicted to act on the distal humerus, with similar forces acting in both radius and ulna. The skeletal structure is well adapted to carry the predicted forces, and onlay-type prostheses are recommended for elbow replacement.

Adult↗
PubMed2007

Effects of adaptation in maintaining high sensitivity over a wide range of backgrounds for Escherichia coli chemotaxis.

An allosteric model is developed to study the cooperative kinase response of wild-type (wt) Escherichia coli cells to the chemoattractant MeAsp in different ambient MeAsp concentrations. The model, together with wt dose response data, reveals the underlying mechanism for E. coli's ability to maintain high sensitivity over a wide range of backgrounds. We find: 1), Adaptation tunes the system to the steepest part of the dose response curve, where the sensitivity to a given type of stimulus is amplified by the number of corresponding receptors in the (mixed) functional receptor complex. A lower bound on the number of Tar receptor dimers (Na) in the complex Na>approximately 6 is obtained from the measured sensitivity. 2), Accurate adaptation synchronizes the kinase activities from different (uncoupled) receptor complexes in a single cell and is crucial in maintaining the high Hill coefficient in the (population averaged) kinase response curve. 3), The wide dynamic range of the high sensitivity can be explained in our model by either having a very small ratio between ligand dissociation constants of the inactive and the active receptors C=0.006, Na=6, and a (methylation level independent) dissociation constant for the inactive Tar receptor K=18.2 microM or by having K and/or Na increase with receptor methylation level together with a larger value of C>0.01. Specific experiments are suggested to distinguish these two scenarios. 4), The receptor occupancy in a wt cell should also adapt and exhibit a slow (approximately logarithmic) dependence on the ligand concentration in the adapted state; this general prediction can be tested experimentally to verify/falsify our model.

Adaptation, Physiological↗
PubMed1999

Effect of antioxidant supplementation on the adaptive response of human skin fibroblasts to UV-induced oxidative stress.

The effect of supplementation with substances having antioxidant properties on the adaptive responses of human skin fibroblasts to UV-induced oxidative stress was studied in vitro. UVR was found to induce a substantial oxidative stress in fibroblasts, resulting in an increased release of superoxide anions and an increase in lipid peroxidation (shown by an elevated malonaldehyde content). Sub-lethal doses of UVR were also found to induce adaptive responses in the fibroblast antioxidant defences, with a transient rise in catalase and superoxide dismutase activities followed by a slower, large increase in cellular glutathione content. Supplementation of the fibroblasts with the antioxidants, Trolox (a water soluble analogue of alpha-tocopherol), ascorbic acid or beta-carotene, had differential effects on these responses. Trolox supplementation reduced the UVR-induced cellular oxidative stress and adaptive response in a predictable concentration-dependent manner. This was in contrast to ascorbic acid which increased superoxide release from fibroblasts. At low doses, ascorbate supplements also reduced the magnitude of the adaptive increases in catalase and superoxide dismutase activities and increase in glutathione content. Beta-carotene had a similar effect to ascorbic acid, reducing the extent of the adaptations to UVR at lower doses while simultaneously increasing superoxide release and malonaldehyde content. These in vitro data indicate that only the vitamin E analogue suppressed UVR-induced oxidative stress in a predictable manner and suggest that common dietary antioxidants may not be equally effective in reducing the potential deleterious effects of UVR-induced oxidative stress in skin.

Adaptation, Physiological↗
PubMed1998

The effect of adapting luminance on the latency of visual search.

Computational models of attentional processing typically view the "attentional spotlight" as a winner-take-all network whose focus can be shifted serially about a display if required. As a result, lateral inhibition is assumed in these models to be an important mechanism involved in visual search. On the basis of this assumption, we predicted that changes in adapting luminance would produce specific changes in search latency functions in virtue of affecting visual inhibition. The results of our first two experiments confirmed these predictions: when search was difficult, and produced reaction time results characteristic of serial processing, there was a main effect of adapting luminance and a significant interaction between adapting luminance and the number of display elements. These effects were both reflected in increases in the slopes and the intercepts of average search latency functions when adapting luminance was decreased. When search was easy, and produced pop out effects characteristic of parallel processing, there were no significant effects of adapting luminance on search latency. The third experiment used adapting luminance to further explore the possibility that arrow junctions are detected preattentively. The results suggested that a visual search for such elements involves a substantial serial component, which weighs against the claim that they are detected by low-level vision.

Adaptation, Ocular↗
PubMed2005

Disability and sunshine: can hedonic predictions be improved by drawing attention to focusing illusions or emotional adaptation?

People frequently mispredict the long-term emotional impact of circumstances. The authors examine 2 causes of such mispredictions-a focusing illusion and underappreciation of adaptation. In Experiment 1, the authors found, in 852 adults, that quality of life estimates (for living with disability) were not increased by reducing focusing illusions. In Experiment 2, the authors found, in 698 adults, that people's disability estimates were increased by asking them to reflect on adaptation. In Experiment 3, the authors found, across 312 Midwestern college students, that both approaches reduced the participants' predictions of the life satisfaction of their peers living in southern California. In the case of living in a better climate, the results suggest that attention to either cause influences people's predictions, whereas in the case of chronic disability, the results suggest that it is easier to get people to appreciate adaptation than it is to reduce focusing illusions.

Adaptation, Psychological↗
PubMed2004

Computational constraints between retrieving the past and predicting the future, and the CA3-CA1 differentiation.

The differentiation between the CA3 and CA1 fields of the mammalian hippocampus is one of the salient traits that set it apart from the organization of the homologue medial wall in reptiles and birds. CA3 is widely thought to function as an autoassociator, but what do we need CA1 for? Based on evidence for a specific role of CA1 in temporal processing, I have explored the hypothesis that the differentiation between CA3 and CA1 may help solve a computational conflict. The conflict is between pattern completion, or integrating current sensory information on the basis of memory, and prediction, or moving from one pattern to the next in a stored sequence. CA3 would take care of the former, while CA1 would concentrate on the latter. I have found the hypothesis to be only weakly supported by neural network simulations. The conflict indeed exists, but two mechanisms that would relate more directly to a functional CA3-CA1 differentiation were found unable to produce genuine prediction. Instead, a simple mechanism based on firing frequency adaptation in pyramidal cells was found to be sufficient for prediction, with the degree of adaptation as the crucial parameter balancing retrieval with prediction. The differentiation between the architectures of CA3 and CA1 has a minor but significant, and positive, effect on this balance. In particular, for a fixed anticipatory interval in the model, it increases significantly the information content of hippocampal outputs. There may therefore be just a simple quantitative advantage in differentiating the connectivity of the two fields. Moreover, different degrees of adaptation in CA3 and CA1 cells were not found to lead to better performance, further undermining the notion of a functional dissociation.

Action Potentials↗
PubMedDate not supplied

The relationship of family dynamics/social support to patient functioning in IDDM patients on intensive insulin therapy.

A 6 month pilot study was conducted to examine the relationship between family dynamics/social support and patient functioning in diabetic patients on intensive insulin therapy. Intensified therapy was associated with improvements in the DUHP symptom score, MHI psychological well-being score, and in the DUHP social functioning score. In diabetic patients, regardless of therapy, extreme family dynamics were correlated with higher DUHP symptom scores and lower MHI psychological well-being scores at the initial measurement time. However, over the 6 month study period, extreme family dynamics were predictive of improvements in the DUHP symptoms score and in the quality of friendships in diabetic patients on intensive insuline therapy. In diabetic patients, regardless of therapy, higher levels of social support correlated with higher levels of psychological and social functioning at the initial measurement time, and with improvements in quality of family life over the 6 month measurement time. Higher social support was also associated with improvements in quantity of friends and the DUHP social functioning score in diabetic patients on intensive insulin therapy. The study also generated empiric support for co-evolutionary models of disease states/family dynamics/treatment systems by showing that 6 month changes in family dynamics were predicted by the initial FACES adaptability measure and the initial mean monthly glucose value. Intensified therapy predicted lower family cohesion and more family rigidity over the 6 month study period. These findings also suggest, when combined with the result that diabetic patients from more cohesive families experienced a rise in monthly mean glucose values, that some diabetic patients may become trapped in a vicious cycle which perpetuates poor glucose control and extreme family dynamics.

Adaptation, Psychological↗
PubMed2003

An adaptation of the Framingham coronary heart disease risk function to European Mediterranean areas.

AIM: To determine whether the Framingham function accurately predicts the 10 year risk of coronary disease and to adapt this predictive method to the characteristics of a Spanish population. METHOD AND RESULTS: A Framingham function for predicting 10 year coronary deaths and non-fatal myocardial infarction was applied to the population of the province of Gerona, Spain, where the cumulated incidence rate of myocardial infarction has been determined since 1988 by a specific registry. The prevalence of cardiovascular risk factors in this region of Spain was established in 1995 by a cross sectional study on a representative sample of 1748 people. The number of cases estimated by the Framingham function for 10 year coronary deaths and non-fatal myocardial infarction was compared with that observed. The Framingham function estimated 2425 coronary heart disease cases in women and 1181 were observed. In men, 9919 were estimated and 3706 were observed. Recalibrating the Framingham equations to the event rate and the prevalence of the risk factors in Gerona led to estimates very close to the number of cases observed in Gerona men and women. CONCLUSIONS: The Framingham function estimates more than doubled the actual risk of coronary disease observed in north east Spain. After calibration, the Framingham function became an effective method of estimating the risk in this region with low coronary heart disease incidence.

Adult↗
PubMed2003

The influence of cellular physiology on the initiation of mutational pathways in Escherichia coli populations.

The factors affecting the direction of evolutionary pathways and the reproducibility of adaptive responses were investigated under closely related but non-identical conditions. Replicate chemostat cultures of Escherichia coli were compared when adapting to partial or severe glucose limitation. Four independent populations used a reproducible sequence of early mutational changes under both conditions, with rpoS mutations always occurring first before mgl. However, there were interesting differences in the timing of mutational sweeps: rpoS mutations appeared in a clock-like fashion under both partial and severe glucose limitation, while mgl sweeps arose under both conditions but at different times. Interestingly, malT and mlc mutations appeared only under severe limitation. Even though the ancestors were genotypically identical, the semi-differentiated properties of bacteria growing with mild or severe glucose limitation sent the populations in characteristic directions. Mutation supply and the fitness contribution of mutations were estimated and demonstrated to be potential influences in the choice of particular adaptation pathways under severe and mild glucose limitation. Predicting all the mutations fixed in adapting populations is beyond our current understanding of evolutionary processes, but the interplay between ancestor physiology and the initiation of adaptation pathways is demonstrated and definable in bacterial populations.

Adaptation, Physiological↗
PubMed2005

Prediction in the timing of pursuit eye movement initiation revealed by cross-axis vestibular-pursuit training in monkeys.

The smooth-pursuit system interacts with the vestibular system to maintain the image of a moving target on the fovea. Efficient tracking performance requires information about the velocity and the initiation of target motion. Previous studies in monkeys have shown that training with orthogonal pursuit and whole body rotation results in adapted eye movement direction during chair rotation. In addition, the latency of the pursuit shortens and initial eye velocity increases in a task-dependent manner. To examine whether these adapted eye movements are predictive pursuit, we studied whether our monkeys could predict the timing of smooth eye movement initiation during chair rotation. Two young Japanese monkeys were rotated horizontally in a trapezoidal waveform (20 degrees/s, +/-10 degrees) with random inter-trial intervals. A laser spot was moved vertically with the same trajectory at a constant delay ranging from 100 to 700 ms after the onset of the chair motion. The monkeys were required to pursue the spot. After this training, the latencies of pursuit eye movements following the onset of chair motion were examined in the presence of the target motion. The target was also briefly (for 500-700 ms) extinguished at 80 ms after the onset of chair rotation. Pursuit eye movements after training were initiated before the onset of target motion and the latencies were proportional to the delays used for training. The latencies and response magnitudes of pursuit with or without target blanking were similar. The auditory-pursuit training did not induce an initial pursuit response similar to that induced by vestibular-pursuit training. These results indicate that smooth eye movements during the chair rotation after the vestibular-pursuit training included a predictive pursuit component. The monkeys' estimate of the delays revealed by the latencies of pursuit was shorter by 22-36% than the actual delays.

Adaptation, Physiological↗
PubMed2006

Predicted highly expressed genes in Nocardia farcinica and the implication for its primary metabolism and nocardial virulence.

Nocardia farcinica is a Gram positive, filamentous bacterium, and is considered an opportunistic pathogen. In this study, the highly expressed genes in N. farcinica were predicted using the codon adaptation index (CAI) as a numerical estimator of gene expressivity. Using ribosomal protein (RP) genes as references, the top approximately approximately 10% of the genes were predicted to be the predicted highly expressed (PHX) genes in N. farcinica using a CAI cutoff of greater than 0.73. Consistent with earlier analysis of Streptomyces genomes, most of the PHX genes in N. farcinica were involved in various 'house-keeping' functions important for cell growth. However, 15 genes putatively involved in nocardial virulence were predicted as PHX genes in N. farcinica, which included genes encoding four Mce proteins, cyclopropane fatty acid synthase which is involved in the modification of cell wall which may be important for nocardia virulence, polyketide synthase PKS13 for mycolic acid synthesis and a non-ribosomal peptide synthetase involved in biosynthesis of a mycobactin-related siderophore. In addition, multiple genes involved in defense against reactive oxygen species (ROS) produced by the phagocyte were predicted with high expressivity, which included alkylhydroperoxide reductase (ahpC), catalase (katG), superoxide dismutase (sodF), thioredoxin, thioredoxin reductase, glutathione peroxidase, and peptide methionine sulfoxide reductase, suggesting that combating against ROS is essential for survival of N. farcinica in host cells. The study also showed that the distribution of PHX genes in the N. farcinica circular chromosome was uneven, with more PHX genes located in the regions close to replication initiation site. The results provided the first estimates of global gene expression patterns in N. farcinica, which will be useful in guiding experimental design for further investigations.

Animals↗
PubMed1999

Testing a model of family stress and coping based on war and non-war stressors, family resources and coping among Lebanese families.

This study was undertaken to describe the objective stressors, perceived stress, coping, and resources of families living in Beirut during the Lebanese war (1975-1991) and to test a model predicting the relationships of these variables to family adaptation. The sample consisted of 438 families chosen at random. Independent variables included objective stressors and perceived stress. The mediating variables were family resources and coping strategies. The dependent variables were health and interactional indicators of family adaptation: physical and psychological health, depression, and interpersonal and marital relationships. Findings provided support for the theoretical framework. Multiple regression analyses revealed that perceived stress, rather than the objective occurrence of events, predicted family adaptation. Family resources, particularly social support, positively impacted family adaptation and was associated with increased use of cognitive coping. The findings provide a theoretical model which, on further testing, can serve as a basis for practice by health professionals when working with traumatized families.

Adaptation, Psychological↗
PubMed1984

A cholinomimetic model of motion sickness and space adaptation syndrome.

The space adaptation syndrome is one of the more vexing problems confronted by our nation's astronauts during their journeys. This syndrome may be a variant of motion sickness, although this possibility has been questioned. Physostigmine, a centrally active cholinesterase inhibitor which increases brain acetylcholine, was found to cause a motion sickness-like syndrome--in psychiatric patients and normals--including nausea, emesis, malaise, dysphoria, increases in serum ACTH, beta-endorphin, cortisol, and prolactin, Neostigmine, a non-centrally acting cholinesterase inhibitor, and saline placebo caused no such effects. The above effects closely parallel those of motion sickness. Thus, the effects of physostigmine may be a convenient model for screening for treatments for motion sickness or space adaptation syndrome, or for predicting who will develop these syndromes.

Adaptation, Physiological↗
PubMed2001

Herbivore host choice and optimal bad motherhood.

When theory predicts which phenotypes are well adapted to a given environment, the data do not always match the predictions. Host-plant selection by herbivorous insects is one such example. Herbivorous insects often appear to make poor choices about where their offspring should develop. New evidence presented by Scheirs et al. suggests that adult insects can choose oviposition sites that enhance their own long-term fitness at the expense of their individual offspring. This suggests that herbivorous insects might be genuinely bad mothers, that host choice is nonetheless adaptive, and that theory needs to incorporate new assumptions about host effects on adult performance.

Journal Article↗
PubMed2000

A randomized controlled trial of alternative modes of service provision to young children with cerebral palsy in Bangladesh.

OBJECTIVE: To compare the efficacy of an outreach program for young children with cerebral palsy with center-based and "minimal intervention" control groups. DESIGN: Randomized controlled trial conducted in a group of 85 children between the ages of 1.5 and 5 years. Urban children were allocated to a daily center-based mother-child group or to monthly training of their parents along with a pictorial guidance manual. Rural children were allocated either to parent training or health advice. Outcome measures were changes in children's adaptive skills, maternal stress and adaptation to the child, satisfaction with social support, and knowledge of handling a physically disabled child. RESULTS: Fifty-eight children were successfully followed up. The pattern of change in children's adaptive skills was as predicted (ie, least progress in the health advice group). Positive effects of intervention also included increased maternal knowledge and perceived helpfulness of support from formal sources. However, maternal adaptation increased most in the health advice group with minimal intervention. When children had attended a program at least 4 times, their skills improved, and mothers' adaptation did increase. CONCLUSIONS: Outreach training for mothers in Bangladesh can help them to improve the skills of their young children with cerebral palsy and is perceived as helpful.

Bangladesh↗