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PubMed1983

Brief psychotherapy in late adolescence: a psychodynamic and developmental approach.

Four cases were discussed in which college students presented themselves in crisis for psychiatric treatment; each was dealing with a normal developmental crisis of late adolescence centering around separation-individuation issues. A type of brief psychotherapy was described which maintained the focus on the primary dynamic conflict and promoted ego development by interpreting the unconscious intrapsychic conflict. The incestuous, aggressive, and regressive themes were explored, and defenses were actively interpreted whenever they interfered with the awareness of autonomous strivings consistent with the ego ideal. Although other authors have emphasized the necessity of establishing a contract early which specifies the number of visits, we have emphasized the importance of maintaining strict therapeutic neutrality, especially regarding the duration of treatment with late adolescents. We view this as an important cornerstone of technique in assisting the healthy late adolescent in his quest for increasing autonomy, ego-ideal integration and ego mastery.

Adjustment Disorders↗

PubMed2001

Joining with resistance: addressing reluctance to engage in group therapy training.

Although research has documented the effectiveness of group psychotherapy, trainees are often reluctant to embrace this modality. This reluctance may reflect an informed choice based on knowledge, interest, and skill. Alternatively, reluctance may reflect misinformation or resistance due to conflicted feelings that arise from group dynamics. The latter are a major obstacle to the success of group therapy training and treatment programs. Understanding the origins of this reluctance and the developmental challenges of group therapy for trainees better equips supervisors to address this difficulty. This article uses case examples to illustrate how trainee reluctance emerges. It also provides strategies for working with hesitant trainees. The success of group therapy programs rests on the supervisor's ability to manage trainees' inhibitions to group therapy.

Adult↗

PubMed2002

Drug compliance in adolescents: assessing and managing modifiable risk factors.

Many studies have found that adolescence represents a problem in compliance with prescribed drug regimens. Multiple factors contribute to this problem, including the developmental evolution taking place in the adolescent physique and psyche. Health belief and patient demographic factors, inherent disease and regimen factors, as well as the dynamics between patient and provider may also contribute to problems with compliance to treatment. Simple interventions such as working with the teen to construct a tolerable treatment regimen, assessing anticipated compliance, discussing potential adverse effects, and establishing cues from the adolescent's daily routine can positively impact treatment compliance. Healthcare providers should recognize the fact that psychosocial changes in an adolescent's life can impact upon compliance with medications and enlist the help of their patients in constructing treatment regimens taking into account the individual's lifestyle that may impact upon compliance. In particular, the healthcare provider should ask the adolescents what they anticipate their success with compliance to treatment might be, adverse effects they are concerned about and what cues could best aid the treatment plan. The healthcare provider should then synthesize this information to create the best treatment plan for that patient.

Adolescent↗

PubMed1992

Hip sonography--how reliable? Sector scanning versus linear scanning? Dynamic versus static examination?

In Europe, the use of ultrasonography has become a routine procedure for the detection of hip dislocations and dysplasias; clinical and historical data alone are not fully reliable. Under the right conditions, ultrasonographic examination of the hip can reliably detect hip joints in need of treatment. Furthermore, results are reproducible without the use of roentgenograms; thus the danger of "overtreatment" can be avoided. The use of sector scanners for examinations of hip joints leads to distortions in the geometry of the picture. As a result, the use of linear transducer is presently indispensable. Thanks to a reference level, static examinations of the hip joint provide us with the possibility of measuring and comparing individual hip joints. With dynamic examinations, we can quantify the data and assess hip stability. In fact, the static and dynamic approaches do not exclude but, rather, complement each other. The ultrasonographic method must be learned from experts. Given the above-mentioned conditions, all developmental abnormalities of the hip can be diagnosed in the first six weeks of life, and healthy hip joints can be clearly distinguished from those requiring follow-up examination. Based on observations on 8530 cases, hip joints of infants at least 4.5 months of age can be successfully treated in a conservative manner. Femoral head necroses have disappeared altogether and the need for later surgery has decreased dramatically.

Hip Dislocation, Congenital↗

PubMed1986

[Changes in cAMP reception in the cytosol of the developing rat kidney].

The age-dependent changes in the cAMP-binding activity of renal papillary cytosol were studied in intact rats and in animals with experimental delay in development of the concentrating renal function induced by hydrocortisone injection in early postnatal period. The age dynamics of specific cAMP binding in the experimental group differ significantly from that in intact and control (sham injected) animals. It is suggested that the developmental changes in experimental animal kidneys are due to disturbances in hormonal regulation of renal tissue differentiation caused by the changes in intracellular receptors of cAMP. Another possible reason for the observed delay of development of the renal function is the weakening of the stimulating effect of endogenous cAMP on the genome function due to cAMP receptor deficiency in the cell.

Aging↗

PubMed2004

A gene regulatory network model for cell-fate determination during Arabidopsis thaliana flower development that is robust and recovers experimental gene expression profiles.

Flowers are icons in developmental studies of complex structures. The vast majority of 250,000 angiosperm plant species have flowers with a conserved organ plan bearing sepals, petals, stamens, and carpels in the center. The combinatorial model for the activity of the so-called ABC homeotic floral genes has guided extensive experimental studies in Arabidopsis thaliana and many other plant species. However, a mechanistic and dynamical explanation for the ABC model and prevalence among flowering plants is lacking. Here, we put forward a simple discrete model that postulates logical rules that formally summarize published ABC and non-ABC gene interaction data for Arabidopsis floral organ cell fate determination and integrates this data into a dynamic network model. This model shows that all possible initial conditions converge to few steady gene activity states that match gene expression profiles observed experimentally in primordial floral organ cells of wild-type and mutant plants. Therefore, the network proposed here provides a dynamical explanation for the ABC model and shows that precise signaling pathways are not required to restrain cell types to those found in Arabidopsis, but these are rather determined by the overall gene network dynamics. Furthermore, we performed robustness analyses that clearly show that the cell types recovered depend on the network architecture rather than on specific values of the model's gene interaction parameters. These results support the hypothesis that such a network constitutes a developmental module, and hence provide a possible explanation for the overall conservation of the ABC model and overall floral plan among angiosperms. In addition, we have been able to predict the effects of differences in network architecture between Arabidopsis and Petunia hybrida.

Arabidopsis↗

PubMed2005

Metabolic markers of developmental competence for in vitro-matured mouse oocytes.

In vitro maturation of oocytes has enormous potential in assisted reproductive technology, but its use has been limited due to insufficient knowledge of oocyte physiology during this dynamic period and lack of an adequate maturation system. The aim of this study was to characterize the metabolic profiles of three groups of oocytes throughout maturation: cumulus-oocyte complexes (COCs), denuded oocytes, and denuded oocytes co-cultured with cumulus cells. Mouse oocytes were collected from 28-day-old unstimulated females and matured in a defined medium. Oocytes were matured individually and transferred into fresh 0.5 microl drops of medium at 4 h intervals until 16 h. Ultramicrofluorimetry was used to quantitate carbohydrate consumption from and metabolite release into the medium. Glucose consumption and lactate production of COCs increased (P < 0.001) over the maturation interval (0-16 h). Glucose consumption by COCs that subsequently fertilized was higher between 8-12 h of maturation than by COCs that did not fertilize (38 versus 29 pmol/COC per h, respectively; P < 0.01). Lactate production by COCs that subsequently fertilized was higher between 8-16 h of maturation, than by oocytes that did not fertilize (8-12 h, 66 versus 46 pmol/COC per h, P < 0.01; 12-16 h, 56 versus 40 pmol/COC per h, respectively; P < 0.05). These data indicate that the final hours of maturation may hold a unique marker of oocyte competence, as during this time fertilizable COCs take up more glucose and produce more lactate than those not subsequently fertilized.

Animals↗

PubMed2001

Comparison of connexin 43, 40 and 45 expression patterns in the developing human and mouse hearts.

The mouse is currently widely used as a model organism in the analysis of gene function but how developmentally regulated patterns of connexin gene expression in the mouse compare with those in the human is unclear. Here we compare the patterns of connexin expression in the heart during the development of the mouse (from embryonic day 12.5 to 6 weeks postpartum) and the human (at 9 weeks gestation and adult stage). The extent of connexin43 expression in the ventricles progressively increased during development of the mouse heart. The developmental pattern of expression for connexins 40 and 45 in the mouse heart was similar, but not identical, and in the ventricles showed a progressive and preferential expression in the conduction system. In general, these dynamic changes of connexins 43, 40 and 45 during mouse cardiac development appear to be mirrored in the human.

Adult↗

PubMedDate not supplied

Developmental mechanisms of threshold evolution in a polyphenic beetle.

Polyphenic development is thought to play a pivotal role in the origin of morphological novelties. However, little is known about how polyphenisms evolve in natural populations, the developmental mechanisms that may mediate such evolution, and the consequences of such modification for patterns of morphological variation. Here we examine the developmental mechanisms of polyphenism evolution in highly divergent natural populations of the dung beetle, Onthophagus taurus. Males of this species express two alternative morphologies in response to larval feeding conditions. Favorable conditions cause males to grow larger than a threshold body size and to develop a pair of horns on their heads. Males that encounter relatively poor conditions during larval life do not reach this threshold size and remain hornless. Exotic populations of O. taurus have diverged dramatically in body size thresholds in less than 40 years since introduction to new habitats, resulting in the expression of highly divergent and novel horn length-body size scaling relationships in these populations. Here we show that larvae of populations that have evolved a larger threshold body size (1) have to accumulate greater mass to become competent to express the horned morph, (2) require more time to complete the final instar, (3) are less sensitive to the juvenile hormone (JH) analogue methoprene, and (4) exhibit a delay in the sensitive period for methoprene relative to other developmental events. JH has been shown previously to control horn expression in this species. Our results show that threshold evolution may be mediated via changes in the degree and timing of sensitivity to JH and may result in correlated changes in the dynamics and duration of larval development. Strain-specific differences in JH sensitivity have previously been demonstrated in other insects. However, to the best of our knowledge this is the first demonstration that changes in the timing of the sensitive period for JH may play an equally important role in the evolution of novel thresholds. We discuss our findings in the context of the developmental regulatory mechanisms that underlie polyphenic development and use our results to explore the consequences of, and constraints on, polyphenism evolution in nature.

Animals↗

PubMed1995

Tubulin dynamics in neuronal axons of living zebrafish embryos.

The mechanism of cytoskeletal protein transport, especially the question of what kind of form the cytoskeletal proteins assume during transport in neurons in situ, has been an important, as yet unsettled issue. To clear up this matter, we adopted the embryonic zebrafish as a living animal model and applied the fluorescence recovery after photobleaching (FRAP) method. The zebrafish embryo is appropriate for this kind of study because of its transparency during the early developmental stage, allowing the observation of neurons that incorporate the microinjected fluorescent tubulin directly under fluorescence microscopy. FRAP revealed no movement of the bleached zone proximodistally, where fluorescence recovered gradually (recovery half-time, 44.2 +/- 11.2 min; n = 36), suggesting that the polymers are stationary but dynamic and that the true moving form could be small oligomers or heterodimers.

Animals↗

PubMed2005

Methylation of histones: playing memory with DNA.

Nucleosomal histones can be methylated in vivo at multiple residues and defined methylation patterns are related to distinct functional readouts of chromosomal DNA. Histone methylation has emerged as an important post-translational modification involved in transcriptional regulation and genome integrity. Recent progress in determining the cis and trans determinants of this process revealed multiple roles for histone methylation in epigenetic memory of active and silent states. The analysis of imprinted, X-linked and heterochromatic sequences disclosed mechanistic similarities for heritable transcriptional repression, pointing to a common mode of action. Moreover, the view of histone methylation as a stable modification has recently been challenged by studies revealing a number of pathways that are capable of removing histone methylation. Thus, in addition to having great in vivo complexity, this modification appears more dynamic then was previously thought.

Animals↗

PubMed1982

Short first ray as a complication of multiple metatarsal osteotomies.

Multiple metatarsal osteotomy was performed in 50 children and found to be a reliable procedure for treatment of metatarsus adductus in a child. As a prerequisite to the operation, the epiphysis of the first ray should be ossified. During the operation, the epiphyseal plate must be identified and avoided. After the correction, displacement of the bony fragments may be prevented by wire fixation. The consequences of failure to observe these rules were noted in a patient who was observed for 13 years; despite premature arrest of the physis resulting in 2.5 cm shortening of the first ray, he is asymptomatic and gainfully employed; his foot is testimony to Harris and Beath's concept of the dynamic adaptability of the human foot.

Adult↗

PubMed2005

Smad1 expression and function during mouse embryonic lung branching morphogenesis.

Bone morphogenetic protein (BMP) 4 plays very important roles in regulating developmental processes of many organs, including lung. Smad1 is one of the BMP receptor downstream signaling proteins that transduce BMP4 ligand signaling from cell surface to nucleus. The dynamic expression patterns of Smad1 in embryonic mouse lungs were examined using immunohistochemistry. Smad1 protein was predominantly detected in peripheral airway epithelial cells of early embryonic lung tissue [embryonic day 12.5 (E12.5)], whereas Smad1 protein expression in mesenchymal cells increased during mid-late gestation. Many Smad1-positive mesenchymal cells were localized adjacent to large airway epithelial cells and endothelial cells of blood vessels, which colocalized with a molecular marker of smooth muscle cells (alpha-smooth muscle actin). The biological function of Smad1 in early lung branching morphogenesis was then studied in our established E11.5 lung explant culture model. Reduction of endogenous Smad1 expression was achieved by adding a Smad1-specific antisense DNA oligonucleotide, causing approximately 20% reduction of lung epithelial branching. Furthermore, airway epithelial cell proliferation and differentiation were also inhibited when endogenous Smad1 expression was knocked down. Therefore, these data indicate that Smad1, acting as an intracellular BMP signaling pathway component, positively regulates early mouse embryonic lung branching morphogenesis.

Animals↗

PubMed1989

Expression of L1 and N-CAM cell adhesion molecules during development of the mouse olfactory system.

The expression of the neural adhesion molecules L1 and N-CAM has been studied in the embryonic and early postnatal olfactory system of the mouse in order to gain insight into the function of these molecules during development of a neural structure which retains neuronal turnover capacities throughout adulthood. N-CAM was slightly expressed and L1 was not significantly expressed in the olfactory placode on Embryonic Day 9, the earliest stage tested. Rather, N-CAM was strongly expressed in the mesenchyme underlying the olfactory placode. In the developing nasal pit, L1 and N-CAM were detectable in the developing olfactory epithelium, but not in regions developing into the respiratory epithelium. At early developmental stages, expression of the so-called embryonic form of N-CAM (E-N-CAM) coincides with the expression of N-CAM, whereas at later developmental stages and in the adult it is restricted to a smaller number of sensory cell bodies and axons, suggesting that the less adhesive embryonic form is characteristic of morphogenetically dynamic neuronal structures. Moreover, E-N-CAM is highly expressed at contact sites between olfactory axons and their target cells in the glomeruli of the olfactory bulb. L1 and N-CAM 180, the component of N-CAM that accumulates at cell contacts by interaction with the cytoskeleton are detectable as early as the first axons extend toward the primordial olfactory bulb. L1 remains prominent throughout development on axonal processes, both at contacts with other axons and with ensheathing cells. Contrary to N-CAM 180 which remains detectable on differentiating sensory neuronal cell bodies, L1 is only transiently expressed on these and is no longer detectable on primary olfactory neuronal cell bodies in the adult. Furthermore, whereas throughout development L1 has a molecular form similar to that seen in other parts of the developing and adult central nervous systems, N-CAM and, in particular, N-CAM 180 retain their highly sialylated form at least partially throughout all ages studied. These observations suggest that E-N-CAM and N-CAM 180 are characteristic of developmentally active structures and L1 may not only be involved in neurite outgrowth, but also in stabilization of contacts among fasciculating axons and between axons and ensheathing cells, as it has previously been found in the developing peripheral nervous system.

Animals↗

PubMed2002

Multiple developmental roles of Ahnak are suggested by localization to sites of placentation and neural plate fusion in the mouse conceptus.

Ahnak is a gigantic (700 kD) phosphoprotein with a unique structure whose expression and cellular localization are dynamically regulated during cell cycle progression. Here, we report that Ahnak is localized to sites of major morphogenesis during mouse placentation and neurulation. Ahnak was found in: (i) derivatives of trophectoderm, including chorionic ectoderm prior to and during union with the ectoplacental cone, presumptive syncytiotrophoblast cells in the chorionic labyrinth, and giant cells at the trophoblast-uterine interface; (ii) the allantois prior to, during, and after union with the chorion; and (iii) the tips of the neural plate during formation of the neural tube. On the basis of these observations, we suggest that Ahnak may play heretofore unrecognized roles in tissue union during normal mouse development.

Animals↗

PubMedDate not supplied

Phenotypic and dynamical transitions in model genetic networks. II. Application to the evolution of segmentation mechanisms.

Knowledge of the genetic control of segmentation in Drosophila has made insect segmentation a paradigmatic case in the study of the evolution of developmental mechanisms. In Drosophila, the patterns of expression of segmentation genes are established simultaneously in all segments by a complex set of interactions between transcriptional factors that diffuse in a syncytium occupying the whole embryo. Such mechanisms cannot act in short germ-band insects where segments appear sequentially from a cellularized posterior proliferative zone. Here, we compare mechanisms of segmentation in different organisms and discuss how the transition between the different types of segmentation can be explained by small and progressive changes in the underlying gene networks. The recent discovery of a temporal oscillation in expression during somitogenesis of vertebrate homologs of the pair-rule gene hairy enhances the plausibility of an earlier proposal that the evolutionary origin of both the short- and long germ-band modes of segmentation was an oscillatory genetic network (Newman 1993). An implication of this scenario is that the self-organizing, pattern-forming system embodied in an oscillatory network operating in the context of a syncytium (i.e., a reaction-diffusion system)-which is hypothesized to have originated the simultaneous mode of segmentation-must have been replaced by the genetic hierarchy seen in modern-day Drosophila over the course of evolution. As demonstrated by the simulations in the accompanying article, the tendency for "emergent" genetic networks, associated with self-organizing processes, to be replaced through natural selection with hierarchical networks is discussed in relation to the evolution of segmentation.

Animals↗

PubMed1990

Drosophila fasciclin I, a neural cell adhesion molecule, has a phosphatidylinositol lipid membrane anchor that is developmentally regulated.

Fasciclin I is a homophilic neural cell adhesion molecule which is regionally expressed on a subset of fasciculating axons in both the grasshopper and Drosophila embryo, suggesting a role in axonal recognition. It is also dynamically expressed on a variety of other embryonic tissues. Biochemical analysis of the fasciclin I glycoprotein from Drosophila embryonic membranes and Schneider 1 cells indicates that it is tightly associated with the lipid bilayer by a phosphatidylinositol lipid moiety. In Drosophila embryos a large fraction of fasciclin I protein has lost its membrane anchor. The ratio of this soluble form to the phosphatidylinositol-linked form changes during embryogenesis. We speculate that removal of the phosphatidylinositol lipid from the fasciclin I protein could be a mechanism to regulate its adhesive function.

Amino Acid Sequence↗

PubMed1994

Expression of trkC receptor mRNA during development of the avian nervous system.

Neurotrophin-3 (NT-3) has mitogenic and neurogenic activities on distinct central and peripheral nervous system (CNS and PNS) progenitors in avian embryos. It was therefore important to characterize in detail the expression pattern of TrkC, a high-affinity receptor for NT-3, during nervous system ontogeny. We report that trkC-encoding transcripts are expressed in the CNS primordium in several spatiotemporal distinct waves. trkC mRNA becomes evident in the dividing neuroepithelium where it is expressed homogeneously. A subsequent enhancement of the signal in dorsal areas of the neural tube occurs concomitant with the migration of neural crest cells from the CNS. Expression of trkC mRNA is then reduced in the germinal epithelium while progressively appearing on postmitotic neurons at the periphery of the neural tube. At a time preceeding the onset of normal motoneuron death, trkC signal is transiently undetectable in the ventral third of the neural tube. Diffuse expression in the spinal cord is resumed on embryonic day (E) 7. Subsets of premigratory and migrating neural crest progenitors also express the trkC receptor. Intense trkC signal is then evident throughout the newly organizing dorsal root ganglia (DRG), and becomes later restricted to defined postmitotic neuronal populations. Cranial ganglia also express the trkC gene from early stages of gangliogenesis. Furthermore, whereas the primary sympathetic ganglia show trkC mRNA, in the secondary ganglia a barely detectable signal could be observed. The dynamic up- and down-regulations of trkC reported here to occur both in the CNS and PNS primordia correspond to diverse, though only partially known, developmental processes. Taken together, these results support the notion that the NT-3-TrkC complex mediates diverse functions during neural development.

Animals↗