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PubMed2007

Conservation, convergence, and divergence of light-responsive, circadian-regulated, and tissue-specific expression patterns during evolution of the Arabidopsis GATA gene family.

In vitro analyses of plant GATA transcription factors have implicated some proteins in light-mediated and circadian-regulated gene expression, and, more recently, the analysis of mutants has uncovered further diverse roles for plant GATA factors. To facilitate function discovery for the 29 GATA genes in Arabidopsis (Arabidopsis thaliana), we have experimentally verified gene structures and determined expression patterns of all family members across adult tissues and suspension cell cultures, as well as in response to light and signals from the circadian clock. These analyses have identified two genes that are strongly developmentally light regulated, expressed predominantly in photosynthetic tissue, and with transcript abundance peaking before dawn. In contrast, several GATA factor genes are light down-regulated. The products of these light-regulated genes are candidates for those proteins previously implicated in light-regulated transcription. Coexpression of these genes with well-characterized light-responsive transcripts across a large microarray data set supports these predictions. Other genes show additional tissue-specific expression patterns suggesting novel and unpredicted roles. Genome-wide analysis using coexpression scatter plots for paralogous gene pairs reveals unexpected differences in cocorrelated gene expression profiles. Clustering the Arabidopsis GATA factor gene family by similarity of expression patterns reveals that genes of recent descent do not uniformly show conserved current expression profiles, yet some genes showing more distant evolutionary origins have acquired common expression patterns. In addition to defining developmental and environmental dynamics of GATA transcript abundance, these analyses offer new insights into the evolution of gene expression profiles following gene duplication events.

Amino Acid Motifs↗
PubMed2006

Fast sequence evolution of Hox and Hox-derived genes in the genus Drosophila.

BACKGROUND: It is expected that genes that are expressed early in development and have a complex expression pattern are under strong purifying selection and thus evolve slowly. Hox genes fulfill these criteria and thus, should have a low evolutionary rate. However, some observations point to a completely different scenario. Hox genes are usually highly conserved inside the homeobox, but very variable outside it. RESULTS: We have measured the rates of nucleotide divergence and indel fixation of three Hox genes, labial (lab), proboscipedia (pb) and abdominal-A (abd-A), and compared them with those of three genes derived by duplication from Hox3, bicoid (bcd), zerknüllt (zen) and zerknüllt-related (zen2), and 15 non-Hox genes in sets of orthologous sequences of three species of the genus Drosophila. These rates were compared to test the hypothesis that Hox genes evolve slowly. Our results show that the evolutionary rate of Hox genes is higher than that of non-Hox genes when both amino acid differences and indels are taken into account: 43.39% of the amino acid sequence is altered in Hox genes, versus 30.97% in non-Hox genes and 64.73% in Hox-derived genes. Microsatellites scattered along the coding sequence of Hox genes explain partially, but not fully, their fast sequence evolution. CONCLUSION: These results show that Hox genes have a higher evolutionary dynamics than other developmental genes, and emphasize the need to take into account indels in addition to nucleotide substitutions in order to accurately estimate evolutionary rates.

Amino Acid Sequence↗
PubMed2006

Age-independent synaptogenesis by phosphoinositide 3 kinase.

Synapses are specialized communication points between neurons, and their number is a major determinant of cognitive abilities. These dynamic structures undergo developmental- and activity-dependent changes. During brain aging and certain diseases, synapses are gradually lost, causing mental decline. It is, thus, critical to identify the molecular mechanisms controlling synapse number. We show here that the levels of phosphoinositide 3 kinase (PI3K) regulate synapse number in both Drosophila larval motor neurons and adult brain projection neurons. The supernumerary synapses induced by PI3K overexpression are functional and elicit changes in behavior. Remarkably, PI3K activation induces synaptogenesis in aged adult neurons as well. We demonstrate that persistent PI3K activity is necessary for synapse maintenance. We also report that PI3K controls the expression and localization of synaptic markers in human neuroblastoma cells, suggesting that PI3K synaptogenic activity is conserved in humans. Thus, we propose that PI3K stimulation can be applied to prevent or delay synapse loss in normal aging and in neurological disorders.

Aging↗
PubMed1984

A model framework of alcoholism counseling: cyclic process of intensification, paradoxical shifting, and differentiation.

While recent literature on individual and family therapy has increasingly focused on the nature and use of paradoxical styles of intervention, little has been published concerning the use of paradox in alcoholism counseling. Alcoholism represents a type of problem that can lend itself to the use of such interventions. This paper first reviews the nature of paradoxical styles of intervention in relation to alcoholism. It then presents three developmentally determined paradoxical dynamics: intensification, paradoxical shifting, and differentiation. These are defined and examples from case studies are given for each. Therapists working with alcoholics are encouraged to consider the use of these patterns of response with their clients.

Alcoholism↗
PubMed1983

Treatment of borderline adolescents.

A recent revision of the proposed DSM III description of the borderline category is presented with reference to the work of Masterson (1972) and Grinker (1968). The contributions of Roger Shapiro et al. to a psychoanalytic formulation of the developmental and familial dynamics are summarized with reference to the genetic factors and the lack of validation to date of any general hypothesis. Treatment recommendations of Wolberg, Shapiro and Jacobson (1971) are described. Grinker's operational criteria were chosen for the pilot study: a defect in affectional relationships with no enduring close ties; child-like angry relationships with parental or authority figures, particularly in the dysphoric group; low self-esteem very poor sense of identity; a chronic depression characterized more by loneliness and boredom than by guilt or loss, and a pervading sense of anger or resentment. Cases are presented to illustrate treatment strategies. A brief differential diagnostic statement is made describing "borderline" as a separate category from other disorders manifesting oppositional, antisocial, and violent behavior.

Acting Out↗
PubMed1995

Aloneness in the countertransference.

This survey of a variety of ways in which analysands induce a feeling of aloneness in the analyst includes reference to the developmental origins, unconscious dynamics, and characterological settings of these ways. An account is presented of the role of narrative choice in defining the phenomena of an analysis not just in reporting pre-existing phenomena. Also included are some technical suggestions.

Countertransference↗
PubMed1977

Sources of variation in clinicians' communication to parents about mental retardation.

Sources of variation in clinicians' diagnostic communication to parents of mentally retarded children were identified and examined. Results demonstrated that the nature of clinicians' communication is related to the severity of the child's diagnosis, clinicians' perception of the parents' level of emotional adjustment, whether the clinicians' experienced difficulties in communicating the diagnosis, and their length of clinical experience in the field of developmental disabilities. The dynamics of these relationships were discussed, as were the implications of the findings for future research and for needed changes in the current priority structure of medical education.

Adaptation, Psychological↗
PubMed2004

Butterfly selected lines explore the hormonal basis of interactions between life histories and morphology.

Hormonal mechanisms underlie many life-history traits and their interactions. We studied the role of ecdysteroids with regard to wing pattern and development time of the polyphenic butterfly Bicyclus anynana. Ecdysteroid titers and sensitivity to ecdysone injection were assayed for two-trait selected lines (ventral eyespot size and development time concurrently). These two traits are genetically and phenotypically coupled, having a common endocrinal basis. Two-trait selection had been applied both antagonistically (opposite the correlation) and synergistically (in the same direction as the correlation). Although selected lines had diverged most in eyespot size, the widest differences in timing of ecdysteroid titers were observed between the development time selection regimes; fast selected lines had an earlier hormonal increase after pupation than slow selected lines (even when corrected for differential pupal times). This endocrine peak was also earlier for females than for males. Furthermore, sensitivity to ecdysone injection as measured by a subsequent decrease in pupal time was significantly lower for slow selected lines than for fast or unselected lines. We conclude that the observed response in eyespot size to artificial selection must have been achieved via alteration of, or selection on, other developmental mechanisms, because the dynamics of the alternative, hormonal, pathway were dictated by development time selection. The developmental system is flexible enough to allow evolution in directions opposing the correlation between wing pattern and developmental time, and responses to selection are not constrained by a shared hormonal system.

Animals↗
PubMed2001

Caring dynamics as perceived by staff supporting daily occupations for developmentally disabled adults.

This study addresses caring staff experiences of hindrances and help in the support of daily occupations among people with developmental disabilities. Data were collected by means of a questionnaire consisting of open-ended questions about the staff perceptions of their work experiences. The respondents (n = 81), corresponding to 94.1% of all care staff employed in a geographically defined care area in southern Sweden, worked in various day activity units supporting the daily occupations of their clients. A constant comparative method of data analysis was used. Staff expressions were classified in two main categories of caring dynamics: an operational level and a managerial level. Four areas were identified at the operational level: encountering realities of practice, attitudes to the clients and work demand, using the potential of knowledge and strategies and applying helping actions to the client. The managerial level included two areas, generalized work strategy and individualized work strategy. It is suggested that to develop the quality of interventions for supporting daily activities among persons with developmental disabilities, efforts should be made to identify caring dynamics as experienced by the caring staff.

Adult↗
PubMed2006

Cognitive and emotional differences in young maltreated children: a translational application of dynamic skill theory.

Through a translational approach, dynamic skill theory enhances the understanding of the variation in the behavioral and cognitive presentations of a high-risk population-maltreated children. Two studies illustrate the application of normative developmental constructs from a dynamic skills perspective to samples of young maltreated and nonmaltreated children. Each study examines the emotional and cognitive development of maltreated children with attention to their developing world view or negativity bias and cognitive skills. Across both studies, maltreated children demonstrate negativity bias when compared to their nonmaltreated counterparts. Cognitive complexity demonstrated by the maltreated children is dependent upon a positive or negative context. Positive problem solving is more difficult for maltreated children when compared to their nonmaltreated counterparts. Differences by maltreatment type, severity, timing of the abuse, and identity of the perpetrator are also delineated, and variation in the resulting developmental trajectories in each case is explored. This translation of dynamic skill theory, as applied to maltreated children, enhances our basic understanding of their functioning, clarifies the nature of their developmental differences, and underscores the need for early intervention.

Adult↗
PubMed2003

Developmental dyslexia and discrimination in speech perception: a dynamic model study.

At the behavioral level one of the primary disturbances involved in congenital dyslexia concerns phonological processing. At the neuroarchitectural level autopsies have revealed ectopies, e.g., a reduced number of neurons in the upper layers of the cortex and an increased number in the lower ones. In dynamic models of interacting neuronal populations the behavioral level can be related to the neurophysiological level. In this study an attempt is made to do so at the cortical level. The first focus of this model study are the results of a Finnish experiment assessing geminate stop perception in quasi speech stimuli by 6 month old infants using a head turning paradigm and evoked potentials. The second focus of this study are the results of a Dutch experiment assessing discrimination of transients in speech stimuli, by adult dyslexics and controls and 2 month old infants. There appears to be a difference in the phonemic perceptual boundaries of children at genetic risk for dyslexia and control children as revealed in the Finnish study. Assuming a lowered neuronal density in the 'dyslexic' model, reflecting ectopies, it may be postulated that less neuronal surface is available for synaptic connections resulting in a lowered synaptic density and thus a lowered amount of available neurotransmitter. A lowered synaptic density also implies a reduced amount of membrane surface available for neurotransmitter metabolism. By assuming both, a reduced upper bound of neurotransmitter and a reduced metabolic transmitter rate in the dynamic model, the Finnish experimental results can be approximated closely. This applies both to data from behavioral head turning and that of the evoked potential study. In the Dutch study adult dyslexics show poor performance in discriminating transients in the speech signal compared to the controls. The same stimuli were used in a a study comparing infants from dyslexic families and controls. Using the same transmitter parameters as in modeling the results of the Finnish study, also in this case the experimental results for adults and infants can be approximated closely. Simulation of behavioral and pharmaceutical interventions with the model provide predictions which can be put to the test in experiments.

Dyslexia↗
PubMed2001

Mental development after modified pi procedure: dynamic cranioplasty for sagittal synostosis.

A prospective developmental assessment was performed on 26 patients operated on with dynamic cranioplasty for sagittal synostosis. Because this technique entails the application of compressive force, it was of great concern to assess the effect of surgery on development and mental status. The surgical technique used was a modified pi procedure. Perioperative variables were recorded. Six patients underwent preoperative intracranial pressure (ICP) measurements. To evaluate objectively the developmental outcome, the Griffiths' Mental Development Scales was used for analysis before and after surgery. A parental questionnaire was used for subjective outcome measurement. Preoperative ICP recordings during sleep ranged from 12.8 to 22.8 mmHg (mean, 16.1 mmHg). The mean age at the time for surgery was 6.9 months (range, 4-16 months; standard deviation [SD], 2.32 months). The surgical technique included shortening of the anteroposterior diameter of the skull by a mean of 16.6 mm. The mean global development quotient (GDQ) preoperatively was 104.5 (range, 82-144; SD, 12.4) and the mean GDQ postoperatively was 101.4 (range, 62-129; SD, 13.6). Mean age at follow-up was 16.3 months (range, 9-40 months; SD, 4.04 months). There was no significant correlation between the amount of intraoperative shortening and mental development. In comparison of means, the GDQ preoperatively did not differ significantly from the GDQ postoperatively. The modified pi procedure is safe and efficient. When surgery was performed before 1 year of age, no significant (p = 0.33) effect on mental development-either detrimental or beneficial-was demonstrated.

Child Development↗
PubMed2006

Developmental expression of mouse Follistatin-like 1 (Fstl1): Dynamic regulation during organogenesis of the kidney and lung.

Follistatin-like 1 (Fstl1) is a distantly related homolog of the Activin and Bone Morphogenetic Protein antagonist Follistatin. Interestingly, this molecule also has homology with the extracellular matrix modifying protein BM-40/SPARC/osteonectin. Previous studies in chick have identified Fstl1 as a regulator of early mesoderm patterning, somitogenesis, myogenesis and neural development. In this study, we determine the developmental expression pattern of Fstl1 in the mouse. We find that Fstl1 is ubiquitously expressed in the early embryo, and that expression becomes regionalized later during development. In the majority of tissues, Fstl1 is strongly expressed in the mesenchymal component and excluded from the epithelium. Notable exceptions include the central nervous system, in which Fstl1 expression is entirely absent with the exception of the choroid plexi and floor plate, the lung, in which Fstl1 expression can be seen in airway epithelia and the kidney, in which collecting ducts and nascent nephron epithelia express the highest levels of Fstl1.

Amino Acid Sequence↗
PubMed1999

Emergence of symmetric, modular, and reciprocal connections in recurrent networks with Hebbian learning.

While learning and development are well characterized in feedforward networks, these features are more difficult to analyze in recurrent networks due to the increased complexity of dual dynamics - the rapid dynamics arising from activation states and the slow dynamics arising from learning or developmental plasticity. We present analytical and numerical results that consider dual dynamics in a recurrent network undergoing Hebbian learning with either constant weight decay or weight normalization. Starting from initially random connections, the recurrent network develops symmetric or near-symmetric connections through Hebbian learning. Reciprocity and modularity arise naturally through correlations in the activation states. Additionally, weight normalization may be better than constant weight decay for the development of multiple attractor states that allow a diverse representation of the inputs. These results suggest a natural mechanism by which synaptic plasticity in recurrent networks such as cortical and brainstem premotor circuits could enhance neural computation and the generation of motor programs.

Animals↗
PubMed2004

Developmental expression of methyl-CpG binding protein 2 is dynamically regulated in the rodent brain.

The gene encoding methyl-CpG binding protein 2 (MeCP2) is mutated in the large majority of girls that have Rett Syndrome (RTT), an X-linked neurodevelopmental disorder. To better understand the developmental role of MeCP2, we studied the ontogeny of MeCP2 expression in rat brain using MeCP2 immunostaining and Western blots. MeCP2 positive neurons were present throughout the brain at all ages examined, although expression varied by region and age. At early postnatal ages, regions having neurons that were generated early and more mature had the strongest MeCP2 expression. Late developing structures including cortex, hippocampus and cerebellum exhibited the most significant changes in MeCP2 expression. Of these regions, the cerebellum showed the most striking cell-specific changes in MeCP2 expression. For example, the early-generated Purkinje cells became MeCP2 positive by P6, while the late-generated granule cells did not express MeCP2 until the fourth postnatal week. The timing of MeCP2 expression in the granule cell layer is coincident with the onset of granule cell synapse formation. Although more subtle, the degree of MeCP2 expression in cortex and hippocampus was most closely correlated with synaptogenesis in both regions. Our finding that MeCP2 expression is correlated with synaptogenesis is consistent with the hypothesis that Rett Syndrome is caused by defects in the formation or maintenance of synapses.

Aging↗
PubMed2001

Gene-selective developmental roles of general transcription factors.

Innumerable transcription factors integrate cellular and intercellular signals to generate a profile of expressed genes that is characteristic of the biochemical and cellular properties of the cell. This profile of expressed genes changes dynamically along with the developmental stage and differentiation state of the cell. The biochemical machinery upon which transcription factors integrate their signals is referred to as the general transcription machinery. However, this machinery is not of universal composition, and variants of the general transcription factors play specific roles in embryonic development, reflecting the constraints and requirements of developmental gene regulation.

Animals↗
PubMed2003

A candidate gene for developmental dyslexia encodes a nuclear tetratricopeptide repeat domain protein dynamically regulated in brain.

Approximately 3-10% of people have specific difficulties in reading, despite adequate intelligence, education, and social environment. We report here the characterization of a gene, DYX1C1 near the DYX1 locus in chromosome 15q21, that is disrupted by a translocation t(2;15)(q11;q21) segregating coincidentally with dyslexia. Two sequence changes in DYX1C1, one involving the translation initiation sequence and an Elk-1 transcription factor binding site (-3G --> A) and a codon (1249G --> T), introducing a premature stop codon and truncating the predicted protein by 4 aa, associate alone and in combination with dyslexia. DYX1C1 encodes a 420-aa protein with three tetratricopeptide repeat (TPR) domains, thought to be protein interaction modules, but otherwise with no homology to known proteins. The mouse Dyx1c1 protein is 78% identical to the human protein, and the nonhuman primates differ at 0.5-1.4% of residues. DYX1C1 is expressed in several tissues, including the brain, and the protein resides in the nucleus. In human brain, DYX1C1 protein localizes to a fraction of cortical neurons and white matter glial cells. We conclude that DYX1C1 should be regarded as a candidate gene for developmental dyslexia. Detailed study of its function may open a path to understanding a complex process of development and maturation of the human brain.

Base Sequence↗
PubMedDate not supplied

The development of subjective group dynamics: children's judgments of normative and deviant in-group and out-group individuals.

A developmental model of subjective group dynamics suggests that social identity is sustained first by intergroup biases and later by intragroup biases. In this study 476 English children 5 to 11 years old evaluated the English and German soccer teams, and judged in-group or out-group members whose attitudes toward the teams was normative versus antinormative. Children of all ages expressed intergroup bias. Differential evaluation against in-group deviants and in favor of out-group deviants strengthened with age. Understanding of targets' relative acceptability (differential inclusion) among in-group and out-group members mediated the effects of age and intergroup bias on intragroup bias. Identification with the in-group moderated the effects only among older children.

Attitude↗