The relation of problem behaviors in preschool children to depressive symptoms in mothers and fathers.

The relation of maternal and paternal depressive symptoms to problem behaviors in a nonclinical sample of preschool children was examined. Data were collected from 46 women, their husbands, and their 4-year-old, first-born children. Observed maternal restrictive and punishing behavior and attachment security of the child were considered additional sources of risk for externalizing and internalizing problem behaviors. Different predictors for child externalizing and internalizing behaviors were identified via hierarchical multiple regression analyses. Maternal and paternal depressive symptoms and maternal restrictive and punishing behavior emerged as salient predictors of child internalizing behaviors. For externalizing behaviors, there were significant gender differences: For girls, maternal depressive symptoms made a significant contribution to the model; the model for boys was not significant. The results perhaps reflect different etiological pathways for externalizing and internalizing behaviors, supporting the suggestion that those behaviors are distinct clinical phenomena, even among very young children. The findings also suggest that nonclinical levels of parental symptomatology show systematic relations to children's problem behaviors.

Characterization of fimbria input to nucleus accumbens.

The hippocampal input to the nucleus accumbens was studied by correlative electrophysiological and anatomical techniques in acutely prepared rabbits. Field and extracellular unitary potentials were recorded in the nucleus accumbens following ipsilateral fimbria stimulation. Analysis of the components of the field response was based on the relevant correlations with extracellular unitary activity. The cellular types that are the recipients of the hippocampal projection were determined by combined intracellular horseradish peroxidase (HRP) and Golgi analyses. The distribution of the hippocampal input was determined by combined field potential and current source density analyses. It was found that the ipsilateral fimbria projection was distributed to the dorsal two-thirds of the nucleus, with the projection being heaviest in the more caudal portions of the nucleus. The negative (N) component of the field response was studied by correlating its behavior with the appropriate extracellular unitary recordings. It was concluded that the N-component represented an envelope of monosynaptically activated action potentials. The positive (P) component of the field response throughout the nucleus accumbens was studied pharmacologically with the iontophoretic administration of bicuculline. The P-components, in both the dorsal and ventral regions of the nucleus, were diminished by bicuculline application, indicating that this potential results from the activation of gamma-aminobutyric acid (GABA) mechanisms. The cell populations that are the targets for the hippocampal projections were studied by the technique of intracellular staining with HRP. These results were correlated with the findings of a Golgi analysis. Two distinct cell types were found to respond in a monosynaptic manner to ipsilateral fimbria stimulation. The most common of the two were the small-to medium-sized spiny neurons, and they were distributed throughout the nucleus. These cells have a spherical dendritic arrangement. The second, and most distinctive, of the cell types were the large aspiny neurons. These cells were distributed medially and caudally in the nucleus. Two of the outstanding features of these cells were the expanse of their dendritic domains and the fact that axons originated from relatively remote portions of the dendrites.

[The influence of sodium diphenylhydantoinate on bone healing in the rat]. / Influence du diphénylhydantoinate de soude sur la cicatrisation osseuse chez le rat.

In order to study the action of sodium diphenylhydantoinate (DPH) on bone repair and during apical scars, vitallium implants were included in four maxillary and mandibular bony cavities in Sprague-Dawley rats. After one month, the implants were removed. In half the cavities, selected as the experimental group bleeding was avoided. In the controls, the bony walls were perforated in order to induce formation of a good-quality clot. The day before the implants were removed and everyday until sacrifice, the animals were injected with sodium hydantoinate (10 mg/100g b/w) ip. They were sacrificed 1d, 4d, 8d, 16d, 28d and 56 days after the implants had been removed. The jaws were isolated, prepared for paraffin sections, and the areas of bone repair cut serially and studied under the photonic microscope. Another series of animals without sodium hydantoinate treatment, was studied for comparison. It was concluded that, in animals under DPH treatment: the bone repair was consistently delayed; a good-quality clot led to a better repair than a poor-quality clot which led cogeneralised collagen formation; the bony defects were proportional to the dose of the injected drug; the bony defects were qualitative including: thin bone traceculae, large osteocytes, collagen overgrowth; foreign bodies included in the bony repair areas were often encapsulated and tolerated; the percentage of collagenous bony defects (tapical scars) increased after sodium hydantoine treatment.

Experimental apical scars in rats.

In order to study the etiology of apical scars, vitallium implants were placed in four intra-maxillary and mandibular cavities of Sprague-Dawley rats. After one month the implants were removed. In half of the cavities, which were selected as experimental cavities, bleeding was avoided. In the others, the walls of the cavities were perforated in several places to induce formation of a good-quality clot. These specimens were identified as control cavities. Animals were killed on day 0 and on the second, fourth, eighth, sixteenth, twenty-eighth, and fifty-sixth days after implant extraction. The jaws were isolated and, after fixation, decalcification, and routine procedure for paraffin sections, studied under the light microscope. In the experimental cavities, the bone healing was delayed. Apical scars occurred, even when one of the two cortical bone plates remained intact. Delayed healing has been associated with the absence of a good-quality clot and with the presence of a sequestrum or suture threads in the wound. The proximity of the central nervous system or of a nerve where the cavity was prepared often leads to a delayed bone healing. The interposition of muscle fibers and the proliferation of collagen from the gingival chorion or from the periodontal ligament lead also to collagenous scars.