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PubMed2006

Attachment as an organizer of behavior: implications for substance abuse problems and willingness to seek treatment.

BACKGROUND: Attachment theory allows specific predictions about the role of attachment representations in organizing behavior. Insecure attachment is hypothesized to predict maladaptive emotional regulation whereas secure attachment is hypothesized to predict adaptive emotional regulation. In this paper, we test specific hypotheses about the role of attachment representations in substance abuse/dependence and treatment participation. Based on theory, we expect divergence between levels of maladaptive functioning and adaptive methods of regulating negative emotions. METHODS: Participants for this study consist of a sample of adoptees participating in an ongoing longitudinal adoption study (n = 208). The Semi-Structured Assessment of the Genetics of Alcohol-II 41 was used to determine lifetime substance abuse/dependence and treatment participation. Attachment representations were derived by the Adult Attachment Interview [AAI; 16]. We constructed a prior contrasts reflecting theoretical predictions for the association between attachment representations, substance abuse/dependence and treatment participation. RESULTS: Logistic regression was used to test our hypotheses. As predicted, individuals classified as dismissing, preoccupied or earned-secure reported the highest rates of substance abuse/dependence. Individuals classified as dismissing reported significantly lower rates of treatment participation despite their high rates of substance abuse/dependence. As expected, the continuous-secure group reported lowest rates of both substance abuse/dependence and treatment participation. CONCLUSION: The findings from this study identify attachment representations as an influential factor in understanding the divergence between problematic substance use and treatment utilization. The findings further imply that treatment may need to take attachment representations into account to promote successful recovery.

Adaptation, Psychological↗
PubMed2002

[Adaptive strategies and adaptation after participation in a education program after a first coronary event].

This descriptive correlational study compares adaptive strategies and adaptation according to participation to an outpatient education program "A vous de jouer". Participants more frequently use seeking social support strategies, and eating less fat, participating in physical activity, managing stress behaviors and returning to work. Distancing/escape avoidance strategies are negatively correlated with healthy life style habits, whereas positive reappraisal/problem solving, and seeking social support strategies are positively associated. Positive reappraisal/problem solving, program participation, and the non-use of distancing/escape avoidance strategies, predict adaptation. The use of these adaptive strategies and behaviors is therefore advantageous to coronary patients.

Adaptation, Psychological↗
PubMed2003

Time course and extent of mechanotransducer adaptation in mouse utricular hair cells: comparison with frog saccular hair cells.

Whole cell transduction currents were recorded from hair cells in early postnatal mouse utricles in response to step deflections of the hair bundle. For displacement steps delivered by a stiff probe (1-ms rise time), half-maximal responses decayed monoexponentially with a mean time constant of 30 ms. Adaptation and other transduction properties did not vary systematically with hair cell type (I vs. II) or region (striola vs. extrastriola). Thus regional variation in the phasic properties of utricular afferents arises through other mechanisms. When bundles were deflected by a fluid jet, which delivers force steps, transduction currents decayed about 3-fold more slowly than during displacement steps. A simple model of myosin-mediated adaptation predicts such slowing through forward creep of the bundle during a force step. For a faster stiff probe (rise time 200 micros), step responses of both mouse utricular and frog saccular hair cells decayed with two exponential components, which may correspond to distinct feedback processes. For half-maximal responses, the two components had mean time constants of 5 and 45 ms (mouse) and 2 and 18 ms (frog). The fast and slow components dominated the decay of responses to small and large stimuli, respectively. Adaptation shifts the instantaneous operating range in the direction of the adapting step. In frog saccular hair cells, the operating range shift is a constant percentage of the displacement. In mouse utricular hair cells, the percentage shift increases for large displacements, extending the range of background stimuli over which adaptation can restore instantaneous sensitivity.

Adaptation, Physiological↗
PubMed1991

Recursive parameter identification of constrained systems: an application to electrically stimulated muscle.

In the application of real-time identification methods for diagnosis or adaptive control of biomedical systems, there is often known model information that is ignored. Constraints on the allowable values of parameters, which may be based on physical considerations, are often neglected because the information does "fit" easily into commonly used parameter-identification algorithms. In this paper a method of incorporating constraints on model parameters is developed. This method is applicable to most recursive parameter-identification algorithms. It enforces linear equality constraints on identified parameters. The use of this method for the real-time identification of autoregressive moving-average-type time series models, subject to parameter constraints, is described in detail. These constraints may be time varying. At each time step, the parameter estimate obtained by a recursive least squares estimator is orthogonally projected onto the constraint surface. This simple idea, when appropriately executed, enhances the output prediction accuracy of estimated parameters. Using constraint information in this way is important when we do not wish to destroy a "natural" parameterization of the model (by an initial projection to incorporate equality constraints), or when we cannot use a single initial model simplification (because the constraints are time varying or involve inputs and outputs). Because it improves output prediction at future times, this method is advantageous for use in predictive adaptive controllers. The use of this algorithm is demonstrated in the identification of electrically stimulated quadriceps muscles in paraplegic human subjects, using percutaneous intramuscular electrodes. The nonlinear steady-state force versus pulsewidth recruitment characteristic of the electrode-muscle system is identified simultaneously with the input-output muscle response dynamics, using a Hammerstein-type model. Knowledge of the recruitment curve's shape is translated into constraints on the identified parameters. This information improves the experimental predictive quality of the identified model.

Adult↗
PubMedDate not supplied

Resilience factors associated with adaptation to HIV disease.

This study examines the hardiness dimensions of commitment, challenge, and control as resilience factors in adaptation among persons with symptomatic HIV disease and AIDS. Two hundred participants completed self-report questionnaires measuring hardiness, psychological distress, quality of life, and core personal beliefs. A series of standard multiple regression analyses revealed that high hardiness was significantly related to 1) lower psychological distress levels; 2) higher perceived quality of life in physical health, mental health, and overall functioning domains; 3) more positive personal beliefs regarding the benevolence of the world and people, self-worth, and randomness of life events; and 4) lowered belief in controllability of life events. Commitment was the hardiness factor that most frequently made a unique contribution to predicting adaptation in the regression models. Implications of these findings for understanding HIV-related adaptation and for clinical mental health intervention are considered. Future directions in HIV-related adaptation research are suggested.

Acquired Immunodeficiency Syndrome↗
PubMed1991

Comparative modulations of insulin secretion, pancreatic insulin content, and proinsulin mRNA in rats. Effects of 50% pancreatectomy and dexamethasone administration.

These studies compared measurements of in vivo insulin secretion, insulin stores, and insulin synthesis. Rats were studied at 24 wk of age, either 1 or 20 wk after a sham operation (Sham) or 50% pancreatectomy (Px), reducing beta-cell number. By 20 wk after surgery, an adaptation to pancreatectomy was apparent from results of serial glucose tolerance tests, done in a preliminary protocol. Some of the rats also received dexamethasone (ShamDex and PxDex, respectively), imposing insulin resistance. Insulin secretion was assessed with the acute insulin response to arginine under basal (AIRbas) and maximum glucose-potentiated (AIRmax) states. Pancreatic insulin was measured, and insulin synthesis was estimated by measurement of proinsulin mRNA. At 1 wk after surgery, there was no difference among Sham and Px rats in AIRbas, but in the Px rats, expected reductions of AIRmax, pancreatic insulin, and proinsulin mRNA were found. ShamDex rats had a markedly augmented AIRbas and increased AIRmax and proinsulin mRNA. However, pancreatic insulin was reduced both in ShamDex and PxDex rats. At 20 wk after surgery, the predicted adaptation to Px was substantiated by AIRmax and proinsulin mRNA in Px rats not different from those in Sham rats, but pancreatic insulin in the Px rats remained low. AIRbas and proinsulin mRNA were augmented in ShamDex and PxDex rats, but pancreatic insulin was again reduced, and in PxDex rats, low AIRmax and fed hyperglycemia were seen. Linear correlations of AIRbas and AIRmax with proinsulin mRNA were observed over a roughly fourfold range of secretion and synthesis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adaptation, Physiological↗
PubMed2002

Marijuana use among the adolescent children of high-risk drug-abusing fathers.

This study examines marijuana use among children of male drug abusers. Subjects were 83 African-American and European-American male drug abusers, of whom the majority were injection drug users, and their children. Thirty-one of the fathers were HIV-positive and 52 were HIV-negative. Using logistic regression analyses, we explored cross-sectionally the relationship between four psychosocial domains (ie, paternal attributes, adolescent problem behaviors, father-adolescent relations, and environment) and adolescent marijuana use. The father's use of illegal drugs and his failure to cope adaptively predicted adolescent marijuana use, while a close father-child bond predicted less adolescent marijuana use. Adolescent problem behaviors predicted an increased likelihood of marijuana use. Furthermore, hierarchical regression analysis demonstrated that the adolescent's problem behavior mediated the associations between both the father-adolescent relationship and environmental factors with adolescent marijuana use. Reducing the risk factors and enhancing the protective factors within each of the domains could help reduce marijuana use among the adolescent children of drug-abusing fathers. Moreover, if a father is a drug abuser, it is important to help him establish a close bond with his child in order to help attenuate the influence of his drug use on the child's marijuana use.

Adaptation, Psychological↗
PubMed2006

Little evidence for early programming of weight and insulin resistance for contemporary children: EarlyBird Diabetes Study report 19.

OBJECTIVE: The aim of this study was to evaluate whether adaptive responses made to the uterine or very early infant environment are affecting the current metabolic health of young children in the United Kingdom. METHODS: Participants were 300 healthy children and their parents from the EarlyBird Diabetes Study cohort. Children were recruited from randomly selected schools at 5 years of age. Retrospective measures were maternal prepregnancy weight (n = 230), maternal fasting glucose levels at 28 weeks of pregnancy (n = 27), birth weight, and infant weight at ages 3 and 6 weeks. Prospective measures were insulin resistance, height, weight, and percentage of body fat (sum of 5 skinfold measurements) at ages 5, 6, 7, and 8 years. RESULTS: Maternal third-trimester fasting glucose levels were associated positively with birth weight but were not associated with either weight or insulin resistance for the same children at 8 years. Birth weight was unrelated to insulin resistance at 8 years. There were no relationships between weight change in the first weeks of life and weight, percentage of fat, or insulin resistance at 8 years. Longer breastfeeding correlated inversely, although weakly, with percentage of body fat for boys only. Current weight was correlated with insulin resistance at 8 years. CONCLUSIONS: For these contemporary children, neither the gestational environment nor early postnatal growth predicted insulin resistance, which was best predicted by current weight. There was no evidence that predictive adaptive responses made by the fetus or infant affected the child's weight or insulin resistance later in childhood.

Adult↗
PubMed1986

Pupation-temperature range in 12 Drosophila species from different ecological backgrounds.

A comparison of pupation-temperature range was made in the laboratory on a temperature gradient (3-38 degrees C) using 12 species of Drosophila representing four species groups and four different ecological backgrounds (temperate-montane forest: virilis group; desert: repleta group; cosmopolitan: melanogaster group; tropical forest: willistoni group). Within groups, differences are found which usually reflect species' distributions. Comparisons of species' mating-, oviposition- and pupation-temperature ranges reveal that pupation most often occurs at temperatures beyond those for mating and oviposition. Each species reflects a different combination of temperature effects. Individual species have different temperature-limits for mating, oviposition and pupation. Temperatures permissive for one response are not predictive of limits on other responses. Among species, temperature can affect a particular response differently. Within groups, species differences can be at high and/or low temperatures for any response, and temperature effects among closely related species can manifest themselves in one, or any combination of responses. One cannot predict which responses will be most and least limited, or at which end of the temperature scale a response will be most limited. Among groups, common, but not absolute temperature ranges generally correspond to the geographic distributions and ecological backgrounds of the species triads. The evaluation of temperature effects on species, based on a single activity, may not be adequate for predicting adaptive strategies.

Animals↗
PubMed2005

Measuring the severity of child maltreatment.

OBJECTIVE: The purpose was to identify different operational definitions of maltreatment severity, and then to examine their predictive validity. METHOD: Children and their primary caregivers participating in a consortium of ongoing longitudinal studies were interviewed when they were approximately 4 and 8 years of age to assess behavior problems, and developmental and psychological functioning. Four different severity definitions were identified and applied to 519 children who were reported for alleged maltreatment between Birth and the Age 8 interview. A taxonomy for defining maltreatment characteristics (Barnett, Manly, & Cicchetti, 1993) was applied to Child Protective Service records to define severity as (a) Maximum Severity within each of five maltreatment types, (b) Overall Maximum Severity across the five types, (c) Total Severity or the sum of the maximum severity for each of five types, and (d) Mean Severity or the average severity for those types of maltreatment alleged, during each of two time periods-Birth to Age 4, and Age 4 to Age 8. RESULTS: Regression analyses that controlled for socio-demographic factors, early maltreatment (Birth to Age 4), prior functioning (Age 4), and site revealed that (a) all four severity definitions for maltreatment reports between Age 4 and Age 8 predicted Age 8 behavior problems, (b) Maximum Severity by Type and Mean Severity predicted adaptive functioning at Age 8, and (c) only Maximum Severity by Type was related to anger, at Age 8. Follow-up regression analyses indicated that only Maximum Severity by Type, specifically physical abuse, accounted for outcomes, beyond maltreatment occurrence versus non-occurrence. CONCLUSION: The results suggest that maltreatment severity definitions that preserve ratings within types of maltreatment may be the optimal approach to measure the severity of children's experiences.

Adaptation, Psychological↗
PubMed2004

Maternal constraint of fetal growth and its consequences.

The major non-genetic factor determining the size of the fetus at term is maternal constraint. This term refers to a set of poorly defined processes by which maternal and uteroplacental factors act to limit the growth of the fetus, presumably by limiting nutrient availability and/or the metabolic-hormonal drive to grow. Maternal constraint can be divided into supply-limited constraint (e.g. maternal size) and demand-driven constraint (e.g. twinning). Maternal constraint acts in all pregnancies, but is greater in some situations, particularly those involving young maternal age, small maternal size, nulliparous and multiple pregnancies. Maternal constraint is an important physiological cause of the variation in birth size, but is not without longer-term consequences. There is increasing evidence that maternal constraint is an important factor in determining the increased risk of adult diseases in those who have poor fetal growth due to pathophysiological factors. The evidence is reviewed and placed in the context of discussing the evolutionary significance of maternal constraint. The role of predictive adaptive responses as the basis of programming, and the effects of maternal constraint on these responses are discussed. Changing demography means that maternal constraint must increasingly be considered as a significant factor in determining the pattern of disease.

Adolescent↗
PubMed2004

Beyond surprise: the puzzle of infants' expressive reactions to expectancy violation.

The reactions of 58 infants to expectancy violation by digitally filtering the experimenter's voice were studied in a cross-sectional design for ages 5, 7, 9, 11-12, and 14 months. The results show that behavioral freezing and changes in gaze direction, but not facial or vocal expression, are reliable responses to expectancy violation. The pattern suggests that a transition in the infant's capacity for cognitive evaluation of novel and discrepant events may occur around age 9 months. These findings confirm the consistent failure to find prototypical facial surprise reactions in research on novel or impossible situations. Componential theories of emotion, which predict adaptive behavior patterns from appraisal processes, may provide clues for underlying mechanisms and generate hypotheses on age-related changes in emotional expression.

Cognition↗
PubMedDate not supplied

Effects of exercise during growth and alternative rearing systems on muscle fibers and collagen properties.

Muscle characteristics, and particularly fiber type frequency and collagen properties, may be a source of variation in eating meat quality. Expanded space allowance in alternative breeding systems theoretically increases animal physical activity during growth. This review deals with effects of endurance training and spontaneous exercise in large areas in- and out-doors, on muscle characteristics in rabbits and pigs, two species of agronomic interest, and rats. Endurance training induces a fast-to-slower transition in myofiber contractile characteristics, following the IIB -> IIX -> IIA -> I transformation sequence. These changes are accompanied by a greater ability to transport fatty acids intracellularly, and (or) by enhanced activities of the mitochondrial reference enzymes. Newly synthesized heat-soluble collagen may be observed in the recruited muscles after endurance training in rats. Depending on the experiments (stocking density, ambient temperature, gender, and muscles), area allowance in- or out-of-doors, does not affect fiber type frequency compared with conventional systems or results in a lower proportion of type IIB/X fibers at the benefit of slower twitch fibers. Muscle lipids and collagen content are generally not modified by expanded indoor area, however, a higher proportion of non-soluble collagen may be observed in free-range animals in doors compared with confined ones. It is impossible to state a general rule for lipid stores and collagen properties in animals reared out-of-doors. Therefore, exercise studies are unsuitable to predict adaptative responses in muscle characteristics to alternative outdoor rearing systems, and in fine meat quality.

Adaptation, Physiological↗
PubMed2001

The development of circadian rhythms in the fetus and neonate.

The circadian time-keeping system is the neural system that allows predictive adaptation of individuals to the reproducible 24-hour day/night alternations of our planet. A biological clock, the suprachiasmatic nucleus, receives environmental information and imposes a circadian pattern to physiological functions. Since the suprachiasmatic nucleus develops early in gestation and circadian rhythms are present in the fetus and newborn, the circadian system seems to be functional in fetal life and can receive circadian inputs through the mother. The neonate moves to an environment in which the main time giving signal is the light:dark cycle. Teleologically, a term newborn should be fit to face this challenge. But this may be quite different for a preterm infant that trades the circadian environment to which it was previously exposed for the timeless environment of the Neonatal Intensive Care Nursery. Scientists and physicians should seek new experimental and clinical approaches to answer the challenging questions of perinatal chronomedicine.

Animals↗
PubMed1984

Clinical correlates of dementia and disability in Huntington's disease.

The relationship of duration of illness and severity of neurological impairment to psychometric performance and activities of daily living was examined in 57 patients with Huntington's Disease (HD). As earlier studies suggested, a distinct cognitive profile characterized patients early in the disease. Duration of symptoms, however, proved to be a weaker correlate of cognitive decline than was motor impairment at the time of testing. For predicting adaptive functioning, both duration of symptoms and neurological status were important variables. This study underscores the limitations of length of illness as a classificatory variable in studies of dementia in HD. We further suggest that future studies consider the contribution of defects in precise timing and sequential operations to the cognitive and adaptive deficits of these patients.

Adult↗
PubMed2003

Genome-wide analysis of NBS-LRR-encoding genes in Arabidopsis.

The Arabidopsis genome contains approximately 200 genes that encode proteins with similarity to the nucleotide binding site and other domains characteristic of plant resistance proteins. Through a reiterative process of sequence analysis and reannotation, we identified 149 NBS-LRR-encoding genes in the Arabidopsis (ecotype Columbia) genomic sequence. Fifty-six of these genes were corrected from earlier annotations. At least 12 are predicted to be pseudogenes. As described previously, two distinct groups of sequences were identified: those that encoded an N-terminal domain with Toll/Interleukin-1 Receptor homology (TIR-NBS-LRR, or TNL), and those that encoded an N-terminal coiled-coil motif (CC-NBS-LRR, or CNL). The encoded proteins are distinct from the 58 predicted adapter proteins in the previously described TIR-X, TIR-NBS, and CC-NBS groups. Classification based on protein domains, intron positions, sequence conservation, and genome distribution defined four subgroups of CNL proteins, eight subgroups of TNL proteins, and a pair of divergent NL proteins that lack a defined N-terminal motif. CNL proteins generally were encoded in single exons, although two subclasses were identified that contained introns in unique positions. TNL proteins were encoded in modular exons, with conserved intron positions separating distinct protein domains. Conserved motifs were identified in the LRRs of both CNL and TNL proteins. In contrast to CNL proteins, TNL proteins contained large and variable C-terminal domains. The extant distribution and diversity of the NBS-LRR sequences has been generated by extensive duplication and ectopic rearrangements that involved segmental duplications as well as microscale events. The observed diversity of these NBS-LRR proteins indicates the variety of recognition molecules available in an individual genotype to detect diverse biotic challenges.

Amino Acid Sequence↗
PubMedDate not supplied

Child development: what do parents expect?

Expectations of future development were assessed in parents of non-disabled children (n = 240) using the Predictive Adaptive Ability Questionnaire (PAAQ). The reliability estimate for the overall PAAQ was 0.90, with a test-retest reliability of 0.99 and an interrater reliability of 0.83. Parental expectations did not significantly differ from normal adaptive ability developmental standards. Longitudinal examination of parental expectations and their influence on child development and the impact of chronic illness on such expectations is recommended.

Achievement↗
PubMed2005

The developmental origins of adult disease.

Epidemiological and clinical observations have led to the hypothesis that the risk of developing some chronic diseases in adulthood is influenced not only by genetic and adult lifestyle factors, but also by environmental factors acting in early life. These factors act through the processes of developmental plasticity and possibly epigenetic modification, and can be distinguished from developmental disruption. The concept of predictive adaptation has been developed to explain the relationship between early life events and the risk of later disease. At its base, the model suggests that a mismatch between fetal expectation of its postnatal environment and actual postnatal environment contribute to later adult disease risk. This mismatch is exacerbated, in part, by the phenomenon of "maternal constraint" on fetal growth, which implicitly provides an upper limit of postnatal nutritional environment that humans have adapted for and is now frequently exceeded. These experimental, clinical and conceptual considerations have important implications for prevention and intervention in the current epidemic of childhood obesity and adult metabolic and cardiovascular disorders.

Birth Weight↗