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Biomedical subjects

H Steiner

Publications and source records attributed to H Steiner.

At least 19 recordsLinked to original sources
PubMed1992

Control of turning behavior under apomorphine by sensory input from the face.

It has been shown that peripheral manipulation of sensory input by removal of vibrissae on one side of the rat's face induces turning behavior which is directed towards the contralateral vibrissae-intact side, under the influence of the dopamine receptor agonist apomorphine. In the present experiment, we examined whether rats under apomorphine turn towards the side with more sensory input, or simply away from the manipulated side. Thus, an experimental manipulation was designed to increase sensory input. Sensory stimulation was applied by attaching a clip into the fur on one side of the face. Rats injected with apomorphine in doses of 0.5-5.0 mg/kg (but not with 0.05 mg/kg or vehicle) exhibited turning behavior towards the side of the clip. This sensory stimulation was also found to influence spontaneous behavioral asymmetries. These results show that an imbalance in sensory input is sufficient to produce turning under apomorphine.

Animals↗
PubMed1992

Time-dependent neuroplasticity in mesostriatal projections after unilateral removal of vibrissae in the adult rat: compartment-specific effects on horseradish peroxidase transport and cell size.

In adult rats the mystacial vibrissae were clipped on one side of the snout, and the influence of this sensory deprivation on crossed and uncrossed striatal afferents from the substantia nigra, ventral tegmental area, and retrorubral area was examined with the horseradish peroxidase tract tracing technique. Unilateral removal of vibrissae was found to affect crossed and uncrossed nigrostriatal projections in a time-dependent manner. One to three days after hemivibrissotomy an apparent neuronal asymmetry was found in the crossed nigrostriatal projection arising in the rostral part of the substantia nigra, with more labeled neurons in the projection to the caudate-putamen on the side of vibrissae removal. This asymmetry resulted mainly from an asymmetry in the subset of nigrostriatal neurons reported to project to the striatal matrix ("dorsal cell type"). In contrast, 4-20 days after hemivibrissotomy reversed asymmetries were found in crossed and uncrossed nigrostriatal projections, with more labeled neurons in the projections to the caudate-putamen of the hemisphere opposite to vibrissae removal (the sensory deprived hemisphere). The asymmetry in the uncrossed projection was found throughout the substantia nigra, but was also most substantial in the projection from its rostral part. The asymmetry in the crossed projection was again restricted to the rostral substantia nigra; interestingly, however, it was limited to the subset of neurons reported to terminate in the striosomes ("ventral cell type"). Evidence was also found for time-dependent changes in size of neurons of the crossed nigrostriatal projections, as well as for changes in striatal afferents from the ventral tegmental area. The time course of these apparent changes in strength of mesostriatal projections is similar to the known time course of recovery from behavioral asymmetries induced by hemivibrissotomy, which is suggestive of a functional relationship between neuronal and behavioral changes. Moreover, the finding of a differential influence of hemivibrissotomy on nigrostriatal afferents to striosomes and matrix is indicative of a functional dissociation of these two systems.

Analysis of Variance↗
PubMed1992

Psychopathology in anorexia nervosa and depression.

It has been hypothesized that anorexia nervosa is characterized by ineffectiveness, interpersonal distrust, and lack of interoceptive awareness. The Eating Disorder Inventory differentiates patients with anorexia nervosa from weight-preoccupied women on the basis of these subscales. To test further the specificity of these characteristics to anorexia nervosa, the Eating Disorder Inventory scores of 20 adolescent girls diagnosed with anorexia nervosa were compared with those of 21 girls with major depression and 21 girls with both anorexia nervosa and depression. Analyses of variance and discriminant function analysis revealed no significant differences in the scores of the three groups. By 2-year followup, subjects initially diagnosed with only anorexia nervosa showed less psychopathology than those with an additional diagnosis of depression. These findings raise further questions about the overlap between depression and anorexia nervosa and leave open the question of characteristic psychological features in anorexia nervosa.

Adolescent↗
PubMed1992

Repressive adaptation and family environment.

The hypothesized connection between adaptive style, specifically repressive adaptation, and the family environments of adolescent clinical samples was investigated. Adolescent patients (n = 221) were studied, who were then divided into four groups matched for sex, age, and socioeconomic status (mean age = 15.7 years, SD 2; sex = 14% boys, 86% girls; SES = 2.4). Grouping was based on the Marlowe Crowne Social Desirability Scale and Spielberger's Trait Anxiety Inventory Scores [repressors (n = 43), impression managers (n = 54), high anxious (n = 55) and low anxious (n = 69)]. Results by MANOVA, Scheffe and discriminate function analysis confirmed our hypothesis. Repressors had distinct family environments as measured by the Family Environment Scale (p = 0.0001). Families were characterized by high levels of cohesion, expressiveness, independence, and organization, displaying correspondingly low levels of achievement orientation, conflict, control and incongruence. Repression may be an effort to adapt to an idealized family environment.

Adaptation, Psychological↗
PubMed1992

Defense style and adaptation in adolescents with depressions and eating disorders.

Maturity of defense style has been associated with the level of adaptive functioning, but few studies have assessed defense style using self-report questionnaires which can provide ratings with great reliability and objectivity. We compared self-perception of defense style (using Bond's Defense Style Questionnaire) with ratings of adaptation assessed retrospectively by two independent raters (using the DSM III-R Global Assessment of Functioning scale) in a population of 100 adolescent girls diagnosed as having either an eating disorder or depression. There was significant correlation between maturity of defense style and level of adaptation, with greater maturity of defense style being associated with higher levels of adaptive functioning. This effect was independent of diagnosis within this population.

Adaptation, Psychological↗
PubMed1992

Respiratory stridor and repressive defense style in adolescent somatoform disorders.

Three cases of adolescents with respiratory stridor of psychiatric etiology are described. All three fulfilled DSM-III-R criteria for diagnoses of somatoform disorders and showed characteristics of repressive defense style. Such patients are likely to undergo extensive medical investigation and treatment if the psychiatric nature of their disorder is not recognized, but few data describing their psychological characteristics or treatment exist. Repressors are typically unaware of emotional arousal and do not recognize the negative affects which lead to their somatic symptoms. They therefore respond poorly to confrontational psychotherapy and are at risk of discontinuing treatment and repeating their maladaptive symptom cycle. Identification of repressive defense style in patients with stridor which has no obvious organic cause may be useful both as a possible "marker" of psychiatric disorder and as a guide to treatment.

Adolescent↗
PubMed1992

["Pseudothrombosis" of the lower leg, induced by a ruptured Baker's cyst].

A sudden onset of unilateral swelling and tenderness on pressure of the calf with no history of trauma is suggestive of vein thrombosis. Baker cysts, especially if ruptured, mimic the clinical picture of deep vein leg thrombosis. The examination method of choice is duplex sonography. We report on a 30-year-old man who was admitted to our hospital with signs of deep vein leg thrombosis. Phlebography revealed normal venous circulation. Examination by duplex sonography showed a ruptured Baker cyst. No intra-articular lesions of the knee joint were revealed by arthroscopy. Histological examination of the biopsy specimens of the synovia showed no specific pathologic condition. The clinical signs improved with conservative treatment.

Adult↗
PubMed1991

Biologically active and amidated cecropin produced in a baculovirus expression system from a fusion construct containing the antibody-binding part of protein A.

A synthetic antibody-binding part derived from protein A from Staphylococcus aureus was used as a fusion partner in a eukaryotic expression system employing Autographa californica nuclear polyhedrosis as a vector. This, in conjunction with an efficient signal sequence, facilitated the purification of the antibacterial peptide cecropin A from the medium of Spodoptera frugiperda cells infected with a recombinant virus. In order to increase further the concentrations of fusion protein, Trichoplusia ni larvae were used as host. Cecropin A could be obtained after cleavage of the fusion protein with CNBr. Biological activity as well as the correct structure including the C-terminal amide group was shown using electrophoresis with detection of antibacterial proteins and mass spectroscopy.

Amino Acid Sequence↗
PubMed1991

Expression of post-translational processing of preprocecropin A using a baculovirus vector.

A cDNA fragment encoding preprocecropin A was inserted into the baculovirus Autographa californica nuclear polyhedrosis virus downstream of the polyhedrin promoter. The gene was expressed in recombinant-infected last instar larvae of Trichoplusia ni and in diapausing pupae of Hyalophora cecropia. The identity of the recombinant product was established by electrophoresis with detection of antibacterial activity and mass spectrometry. The prepropeptide had been correctly processed including removal of signal peptide and pro-part. Biologically active and amidated cecropin A was exported to the hemolymph. The yield of recombinant protein in H. cecropia reached a level of 600 micrograms/ml hemolymph and about 70% of the material was amidated.

Animals↗
PubMed1991

Testing the psychogenic vomiting diagnosis. Four pediatric patients.

We treated four patients with chronic vomiting during childhood in whom a tentative diagnosis of psychogenic vomiting was made after an extensive evaluation. In each case, the diagnosis was reconsidered during the course of treatment, as observations about the patients and their response to interventions accumulated. In three instances, these observations did not fit those expected if the diagnosis of psychogenic vomiting was correct. This led to a reexamination of the organic evaluation and the discovery of an undiagnosed organic contribution to the vomiting. In the fourth patient, gastric emptying studies confirmed that there was a strong psychological contribution to the vomiting, and helped to more carefully define this contribution. Family and individual psychotherapy and treatment were aided by the greater clarity in diagnosis.

Child↗
PubMed1991

The early care and feeding of anorexics.

Comparing mothers' reports of early feeding practices in 18 mothers of anorexics and 25 mothers of normal children by means of a questionnaire, we found that the mothers of anorexics introduced solids earlier and used Schedule rather than Demand feedings more frequently. The mothers of anorexics did not treat patients and control siblings differentially. Our study suggests that differences in early feeding and in infant temperament may be operative in the pathogenesis of anorexia nervosa.

Adolescent↗
PubMed1991

Nodular focal fatty infiltration of the liver in acquired porphyria cutanea tarda.

A case is reported of acquired porphyria cutanea tarda (PCT) due to administered valproate acid in an epileptic patient. Sonography (US) and computed tomography (CT) showed multiple nodular, well-defined lesions of the liver. Biopsy confirmed the diagnosis of focal fatty infiltration and revealed additionally the signs of hepatic involvement in PCT. Focal fatty infiltration should be considered in patients with multiple liver lesions if there is a predisposing condition. PCT can be a further cause of this type of infiltration.

Adult↗
PubMed1991

Asymmetries in thigmotactic scanning: evidence for a role of dopaminergic mechanisms.

In two experiments, the influence of spontaneous asymmetries in thigmotactic scanning was analyzed on spontaneous and drug-induced behavior in the rat. The side of the face with which an animal performed more scanning in a baseline test was defined as the dominant vibrissae side. In experiment 1, repeated testing of either spontaneous thigmotactic scanning, or scanning after apomorphine or amphetamine, yielded no evidence that rats would preferably use one side of the face for scanning, when re-exposed to the same environment. However, an asymmetry in turning was observed both under apomorphine and amphetamine, that is, turning away from the dominant vibrissae side. In experiment 2, an influence of spontaneous asymmetries in scanning was found on behavioral asymmetries induced by unilateral vibrissae removal. Only animals, in which the vibrissae of the non-dominant side had been removed, showed more scanning with the intact vibrissae side, both undrugged and after apomorphine. Turning under apomorphine was more pronounced in animals in which the vibrissae on the dominant side had been removed. These animals showed an asymmetry in turning towards the intact vibrissae side. Furthermore, in both experiments we found evidence for left/right differences in turning or scanning. The results are discussed with respect to possible endogenous substrates of asymmetry, such as within the mesostriatal dopamine system.

Amphetamine↗