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PubMed2004

The aims and accomplishments of comparative psychology.

Greenberg, Partridge, Weiss, and Pisula propose a new perspective of comparative psychology, based in large part on an anagenetic and dynamic systems approach to the development and evolution of behavior. Their view appreciates the probabilistic nature of behavioral development and promotes the value of an integrative levels concept for generating testable hypothesis regarding the complex relationship between biology, context, and developmental history underlying behavioral and psychological functioning. However, the authors fail to represent the full scope of contemporary comparative psychology by overlooking several core aims of the field, including (a) the use of animal models to shed light on human behavior and development and (b) understanding the role of behavior as a leading edge in the evolutionary process.

Animals↗
PubMed1999

Activation of human extrageniculostriate pathways after damage to area V1.

We have used positron emission tomography (PET) to specify the cortical and subcortical structures activated following visual stimulation of the scotomatous field in a patient with an asymmetric bilateral developmental anomaly of the visual cortex. Computerized perimetry indicated a left visual field defect only although MRI and 18FDG-PET scans showed abnormalities in both occipital lobes. The visual stimuli were semicircular gratings moving in opposite directions on a dynamic random-dot background. They were specifically constructed to eliminate intra- and extraocular light scatter and to optimize the activation of extra-striate cortical areas and their projecting subcortical relays. For anatomical localization PET images were coregistered to the subject's MRI in Talairach coordinates. After subtraction of the baseline conditions from the stimulation conditions, a t-statistic map was created on a voxel-by-voxel basis. Stimulation of the scotomatous hemifield yielded significant activations of Brodmann cortical areas 18-19 and 47 as well as the pulvinar thalami of the left hemisphere, in addition to a less prominent activation in the right hemisphere. Stimulation of the intact hemifield produced significant activation of Brodmann cortical areas 30 and 47 of the left hemisphere. These results suggest that in the absence of area V1, residual vision observed in the blind hemifield could be mediated by a retinofugal pathway to extrastriate cortex via the pulvinar.

Adult↗
PubMed2006

Taxol and tau overexpression induced calpain-dependent degradation of the microtubule-destabilizing protein SCG10.

Microtubule-stabilizing and -destabilizing proteins play a crucial role in regulating the dynamic instability of microtubules during neuronal development and synaptic transmission. The microtubule-destabilizing protein SCG10 is a neuron-specific protein implicated in neurite outgrowth. The SCG10 protein is significantly reduced in mature neurons, suggesting that its expression is developmentally regulated. In contrast, the microtubule-stabilizing protein tau is expressed in mature neurons and its function is essential for the maintenance of neuronal polarity and neuronal survival. Thus, the establishment and maintenance of neuronal polarity may down-regulate the protein level/function of SCG10. In this report, we show that treatment of PC12 cells and neuroblastoma cells with the microtubule-stabilizing drug Taxol induced a rapid degradation of the SCG10 protein. Consistently, overexpression of tau protein in neuroblastoma cells also induced a reduction in SCG10 protein levels. Calpain inhibitor MDL-28170, but not caspase inhibitors, blocked a significant decrease in SCG10 protein levels. Collectively, these results indicate that tau overexpression and Taxol treatment induced a calpain-dependent degradation of the microtubule-destabilizing protein SCG10. The results provide evidence for the existence of an intracellular mechanism involved in the regulation of SCG10 upon microtubule stabilization.

Animals↗
PubMed1998

Treatment of eating disorders in children and adolescents.

Anorexia nervosa and bulimia nervosa are expressed differently in children and adolescents than in adults. Consequently, diagnostic procedures and multidisciplinary treatments need to be tailored to the unique developmental, medical, nutritional, and psychological needs of children and adolescents with eating disorders. This paper reviews current research outlining the differences between child, adolescent, and adult eating disorders. Research is then reviewed concerning the effectiveness of hospitalization, partial hospitalization, individual dynamic therapy, cognitive-behavioral therapy, interpersonal therapy, family therapy, and medication for treating anorexia nervosa, bulimia nervosa, and related eating disorders in children and adolescents. Specific recommendations are made for practitioners to tailor these treatments to their eating-disordered child and adolescent patients, following a stepped-care, decision-tree model of intervention that takes into account the effectiveness, cost, and intrusiveness of the interventions.

Adolescent↗
PubMed2005

Amiel-Tison Neurological Assessment at term age: clinical application, correlation with other methods, and outcome at 12 to 15 months.

The aims of this study were: (1) to perform the Amiel-Tison Neurological Assessment (ATNA) in a group of infants with different risk factors for brain damage; (2) to analyze the results of the examinations in light of the risk factors and presumed aetiology; (3) to compare results of examinations with results of cranial ultrasound, electroencephalography (EEG), and cerebral function monitoring (CFM); and (4) to evaluate neurological outcome at 12 to 15 months of age using the Amiel-Tison and Gosselin method, and developmental outcome using the Bayley Scales of Infant Development. Participants were 52 term, newborn infants (31 males, 21 females) with risk factors for brain damage. Mean birthweight was 3288g (SD 661g) and mean gestational age was 39.4wks (SD 1.2wks); range 38 to 41.3wks. Mean age at admission to a neonatal special care unit was 75h, (SD 13.7h). The group with a dynamic (evolving) clinical profile differed significantly from the group with a static (stable) profile in terms of aetiology, while the group with signs of prenatal brain damage differed from the group without these signs regarding aetiology and the level of severity of neurological signs. Sensitivity of the ATNA to detect infants with abnormal ultrasound was 0.97, with EEG 0.89, and with CFM 0.88. At follow-up at 12 to 15 months 47 children were examined: neurological examination was normal in 25 and five children had a minor, five a moderate, and 12 a severe neurological deficit. Agreement of the ATNA with neurological and developmental assessment at follow-up was very good. Our findings suggest that the ATNA is also of value in assessing aetiology and timing of brain lesions.

Brain Damage, Chronic↗
PubMed1998

alpha1,3 Fucosyltransferase, alpha-L-fucosidase, alpha-D-galactosidase, beta-D-galactosidase, and Le(x) glycoconjugates in developing rat brain.

Fucosyltransferases (FTs) and various glycosidases that are involved in the biosynthesis or degradation of SSEA-1 (Le(x)) antigens and their precursors in the CNS are developmentally regulated. In forebrain and cerebellum with lactosamine (LacNAc) as acceptor the FT activity was maximal at P15-P22, but with the glycolipid substrate paragloboside (nLc4) the maximal activity in cerebellum was obtained at P10-P15. The FT activity, with these substrates, was insensitive to N-ethylmaleimide (NEM) and the glycolipid product had an alpha1,3 linkage (Fuc to GlcNAc) suggesting similarities of the investigated enzyme to the cloned human and rat FT IV. However, the observation of different patterns of FT activity in isoelectrofocused fractions (pH 3.5-10) with different types of acceptors, and the differential expression of Le(x) containing glycolipids and glycoproteins during development strongly suggest the presence of more than one type of FT during development. Data on developmental expression of the hydrolytic enzymes, alpha-L-fucosidase, beta-D-galactosidase and alpha-D-galactosidase, which can potentially hydrolyse SSEA-1 or its precursors, support the notion that SSEA-1 expression is the result of a dynamic balance between the activity of transferases and hydrolases.

Animals↗
PubMed2001

The role of early neural activity in the maturation of turtle retinal function.

In the developing vertebrate retina, ganglion cells fire spontaneous bursts of action potentials long before the eye becomes exposed to sensory experience at birth. These early bursts are synchronised between neighbouring retinal ganglion cells (RGCs), yielding unique spatiotemporal patterns: 'waves' of activity sweep across large retinal areas every few minutes. Both at retinal and extraretinal levels, these embryonic retinal waves are believed to guide the wiring of the visual system using hebbian mechanisms of synaptic strengthening. In the first part of this review, we recapitulate the evidence for a role of these embryonic spontaneous bursts of activity in shaping developing complex receptive field properties of RGCs in the turtle embryonic retina. We also discuss the role of visual experience in establishing RGC visual functions, and how spontaneous activity and visual experience interact to bring developing receptive fields to maturation. We have hypothesised that the physiological changes associated with development reflect modifications in the dendritic arbours of RGCs, the anatomical substrate of their receptive fields. We demonstrate that there is a temporal correlation between the period of receptive field expansion and that of dendritic growth. Moreover, the immature spontaneous activity contributes to dendritic growth in developing RGCs. Intracellular staining of RGCs reveals, however, that immature receptive fields only rarely show direct correlation with the layout of the corresponding dendritic tree. To investigate the possibility that not only the presence of the spontaneous activity, but even the precise spatiotemporal patterns encoded in retinal waves might contribute to the refinement of retinal neural circuitry, first we must clarify the mechanisms mediating the generation and propagation of these waves across development. In the second part of this review, we present evidence that turtle retinal waves, visualised using calcium imaging, exhibit profound changes in their spatiotemporal patterns during development. From fast waves sweeping across large retinal areas and recruiting many cells on their trajectory at early stages, waves become slower and eventually stop propagating towards hatching, when they become stationary patches of neighbouring coactive RGCs. A developmental switch from excitatory to inhibitory GABAA responses appears to mediate the modification in spontaneous activity patterns while the retina develops. Future chronic studies using specific spatiotemporal alterations of the waves will shed a new light on how the wave dynamics help in sculpting retinal receptive fields.

Action Potentials↗
PubMed1996

Temporal mapping of gene expression levels during the differentiation of individual primary hematopoietic cells.

A hierarchical order of gene expression has been proposed to control developmental events in hematopoiesis, but direct demonstration of the temporal relationships between regulatory gene expression and differentiation has been difficult to achieve. We modified a single-cell PCR method to detect 2-fold changes in mRNA copies per cell (dynamic range, 250-250,000 copies/cell) and used it to sequentially quantitate gene expression levels as single primitive (CD34+,CD38-) progenitor cells underwent differentiation to become erythrocytes, granulocytes, or monocyte/macrophages. Markers of differentiation such as CD34 or cytokine receptor mRNAs and transcription factors associated with their regulation were assessed. All transcription factors tested were expressed in multipotent progenitors. During lineage-specific differentiation, however, distinct patterns of expression emerged. SCL, GATA-2, and GATA-1 expression sequentially extinguished during erythroid differentiation. PU.1, AML1B, and C/EBP alpha expression profiles and their relationship to cytokine receptor expression in maturing granulocytes could be distinguished from similar profiles in monocytic cells. These data characterize the dynamics of gene expression accompanying blood cell development and define a signature gene expression pattern for specific stages of hematopoietic differentiation.

Adult↗
PubMed1999

Continuous in vitro propagation and differentiation of cultures of the intramolluscan stages of the human parasite Schistosoma mansoni.

The metazoan parasitic blood flukes, Schistosoma spp., infect over 200 million people worldwide and cause extensive human morbidity and mortality. Research strategies for development of anti-schistosomal agents are impeded by the organism's complex molluscan-mammalian life cycle, which limits experimental approaches and availability of material. We derived long-term continuously proliferative cultures of Schistosoma mansoni sporocysts capable of generating cercariae in vitro. Cultured organisms retained the ability to parasitize the host, and they exhibited developmental regulation of candidate stage-specific genes in the host-free culture system. Evidence for expression of a reverse transcriptase also was found in the cultured organisms, pointing to this activity as a possible mechanistic contributor to the dynamic relationship between the parasite and its hosts. Continuous in vitro propagation of the asexual sporocyst stage allows isolation of clonally derived parasite populations and provides a means to study schistosomal molecular genetics, metabolism, and evasion of host defenses.

Animals↗
PubMed1989

An examination of three methods of psychodynamic formulation based on the same videotaped interview.

While psychodynamic theory and therapy are approaching their centennial, the science of psychodynamics is still in an earlier developmental stage. Any scientific field generates the most controversy and excitement when it is still developing. For psychodynamic psychology this means that its basic units of observation as well as its rules for justifying clinical inference in formulating and testing dynamic hypotheses require more development. In short, we are still evaluating different methods for both discovering and validating psychodynamic propositions. This is especially true for central features of dynamic psychology, including intrapsychic conflict, relationships, and transference patterns. This report compares three different methods for making a dynamic case formulation: 1) the Core Conflictual Relationship Theme (CCRT) of Luborsky (Crits-Christoph and Luborsky 1985a,b; Luborsky 1976, 1977, 1984, and companion paper in this issue; Levine and Luborsky 1981), 2) the Plan Diagnosis (PD) method of Silberschatz, Curtis and colleagues of the Mount Zion group (Caston 1986; Curtis and Silberschatz 1986; Rosenberg et al. 1986; Curtis et al. 1988) and, 3) the Idiographic Conflict Formulation (ICF) of Perry and Cooper (1985, 1986, and companion paper in this issue). Each has a slightly different focus. The CCRT focuses on relationship patterns as the central feature of individual dynamics and transference in or out of the treatment situation. The Plan Diagnosis focuses on dynamic features related to transference, resistance and insight in therapy. The Idiographic Conflict Formulation focuses on stress and internal conflict, and the individual's adaptation to them in or out of treatment.

Adjustment Disorders↗
PubMed2006

What mouse mutants teach us about extracellular matrix function.

For many years the extracellular matrix was viewed as a benign scaffold for arranging cells within connective tissues, but it is now being redefined as a dynamic, mobile, and flexible key player in defining cellular behavior. Gene targeting, transgene expression, and spontaneous mutations of extracellular matrix proteins in mice have greatly accelerated our mechanistic view of the structural and instructive functions of the extracellular matrix in developmental and regenerative processes. This review summarizes the phenotypes of genetic mouse models carrying mutations in extracellular matrix proteins, with specific emphasis on recent advances. The application of reverse genetics has demonstrated the multifunctionality of matrix proteins in a biological context and, in addition, has brought a novel perspective to the understanding of human pathologies.

Animals↗
PubMed1997

MAP kinase in situ activation atlas during Drosophila embryogenesis.

Receptor tyrosine kinases (RTKs) and the signaling cascades that they trigger play central roles in diverse developmental processes. We describe the capacity to follow the active state of these signaling pathways in situ. This is achieved by monitoring, with a specific monoclonal antibody, the distribution of the active, dual phosphorylated form of MAP kinase (ERK). A dynamic pattern is observed during embryonic and larval phases of Drosophila development, which can be attributed, to a large extent, to the known RTKs. This specific detection has enabled us to determine the time of receptor activation, visualize gradients and boundaries of activation, and postulate the distribution of active ligands. Since the antibody was raised against the phosphorylated form of a conserved ERK peptide containing the TEY motif, this approach is applicable to a wide spectrum of multicellular organisms.

Animals↗
PubMedDate not supplied

[Clinical logic in orthopaedic surgery for cerebral palsy].

The evolution of muscular contractures and skeletal deformities in cerebral palsy, and criteria for prevention or therapeutical decisions are analized. Developmental brain damage produces a disbalance between bone and muscular growth. Orthopaedic palliative treatments try to avoid malposition of the extremities and to compensate mechanical disbalance during the entire skeletal growth. Therapeutical options are based is on the distinction between dynamic situations and rigid ones; and also on the presence or absence of articular fixed deformities.

Cerebral Palsy↗
PubMed2004

[Neurotransmitter stage in the development of peripheral part of autonomic nervous system].

The dynamics of neurotransmitter stage in the development of autonomic nervous system (ANS) was studied in rats starting from the moment of initial appearance of neurotransmitters acetylcholine and adrenalin in ANS peripheral part main nervous plexuses. Cryostat sections of embryos on developmental days 13.5, 16.5 and 18.5 and of neonatal rats aged 0.5 and 1.5 days were treated with glyoxilic acid, using Karnovsky-Roots method and impregnated with silver nitrate according to Bielschowsky-Gross method. Acetylcholinesterase in vagus and in spinal ganglia was found on day 13.5, while catecholamine in sympathetic trunc was detected in animals immediately after the birth. Periods of the beginning of neurotransmitter stage in ANS development in rat and man were compared and it was established that it was delayed in rat as in immature-born animal.

Acetylcholine↗
PubMed1986

Identification and its vicissitudes as observed in the perversions.

This paper aims to contribute to the clarification of the different meanings of the concept of identification and the different processes involved in the making of an identification, by considering the perversions as disorders of internalization. The different forms of internalization are regarded as lying along a continuum of which identification is at one extreme and involves the incorporation of (part of) the object-representation into the self-representation. The pervert is shown to be unable to carry out the process of identification because he is fixated at an early developmental phase which I refer to as the 'core complex': instead of identification he has to make use of 'stimulation' in which the subject unconsciously models himself on (parts of) the object. The crucial role the body plays in these dynamics is considered. Exploration of these issues highlights how, in order for identification to take place, the issues of the core complex need to be adequately resolved in the course of normal development.

Aggression↗
PubMed2004

The fragile X protein controls microtubule-associated protein 1B translation and microtubule stability in brain neuron development.

The fragile X mental retardation protein (FMRP) is a selective RNA-binding protein implicated in regulating translation of its mRNA ligands. The absence of FMRP results in fragile X syndrome, one of the leading causes of inherited mental retardation. Delayed dendritic spine maturation was found in fragile X mental retardation patients as well as in Fmr1 knockout (KO) mice, indicating the functional requirement of FMRP in synaptic development. However, the biochemical link between FMRP deficiency and the neuronal impairment during brain development has not been defined. How FMRP governs normal synapse development in the brain remains elusive. We report here that the developmentally programmed FMRP expression represses the translation of microtubule associated protein 1B (MAP1B) and is required for the accelerated decline of MAP1B during active synaptogenesis in neonatal brain development. The lack of FMRP results in misregulated MAP1B translation and delayed MAP1B decline in the Fmr1 KO brain. Furthermore, the aberrantly elevated MAP1B protein expression leads to abnormally increased microtubule stability in Fmr1 KO neurons. Together, these results indicate that FMRP plays critical roles in controlling cytoskeleton organization during neuronal development, and the abnormal microtubule dynamics is a conceivable underlying factor for the pathogenesis of fragile X mental retardation.

Animals↗
PubMed1998

Distribution and developmental regulation of metabotropic glutamate receptor 7a in rat brain.

To determine the regional and cellular distribution of the metabotropic glutamate receptor mGluR7a, we used rabbit anti-peptide polyclonal-targeted antibodies against the C-terminal domain of mGluR7a. Here we report that immunocytochemistry at the light-microscopic level revealed that mGluR7a is widely distributed throughout the adult rat brain, with a high level of expression in sensory areas, such as piriform cortex, superior colliculus, and dorsal cochlear nucleus. In most brain structures, mGluR7a immunoreactivity is characterized by staining of puncta and fibers. However, in some regions, including the locus ceruleus, cerebellum, and thalamic nuclei, both cell bodies and fibers are immunopositive. The changes in levels of mGluR7a during development were investigated with immunoblotting and immunocytochemical analysis. Immunoblot analysis revealed that the levels of mGluR7a are differentially regulated across brain regions during postnatal development. In cortical regions (hippocampus, neocortex, and olfactory cortex), mGluR7a levels were highest at postnatal day 7 (P7) and P14, then declined in older rats. In contrast, mGluR7a levels were highest at P7 in pons/medulla and cerebellum and decreased markedly between P7 and P14. In these regions, mGluR7a immunoreactivity was at similar low levels at P14 and P21 and in adults. Immunocytochemical analysis revealed that staining for mGluR7a was exceptionally high in fiber tracts in P7 animals relative to adults. Furthermore, the pattern of mGluR7a immunoreactivity in certain brain structures, including cerebellum, piriform cortex, and hippocampus, was significantly different in P7 and adult animals. In summary, these data suggest that mGluR7a is widely distributed throughout the rat brain and that this receptor undergoes a dynamic, regionally specific regulation during postnatal development.

Age Factors↗
PubMed1997

Dynamics of actin in cardiac myofibrils and fibroblast stress fibers.

The exchangeability of actin in cardiac myofibrils and fibroblast stress fibers was investigated using fluorescent analogue cytochemistry in combination with fluorescence recovery (FR) after photobleaching. Living embryonic chicken cardiac myocytes and fibroblasts were microinjected with rhodamine (rh)-labeled muscle and nonmuscle actins. After incorporation of the fluorescent actin analogue into cellular structures, small areas of labeled structures were photobleached with a laser pulse. In cardiac myofibrils, FR in their proximal striated portions occurred at a slower rate than that in their proximal nonstriated and distal terminal portions with each rh-isoactin injected. Thus, nascent myofibrils at different developmental stages display different actin exchangeabilities. Further, in all portions of myofibrils, FR of rh-muscle actin was faster than that of rh-nonmuscle actin. This indicates that actin molecules in cardiac myofibrils cannot be readily exchanged by heterotypic nonmuscle actin. In fibroblasts, photobleaching of stress fibers yielded similar results in both their proximal mid-points and distal terminal portions, and the FR rate was consistently faster than that observed in any part of the myofibrils. This result seems to be related to the dynamic properties of actin filaments in stress fibers at all portions. Further, the fact that stress fibers possessed a similar exchange rate with muscle and nonmuscle actins appears to be related to a more primitive nature of stress fibers than myofibrils.

Actins↗