[Flexibility of mental representations of spatial information as a function of perspective during learning]. / Flexibilität mentaler Repräsentationen räumlicher Information in Abhängigkeit von der Erwerbsperspektive.

View-based theories of the mental representation of spatial information claim that distinct views experienced during learning are represented separately in memory. Networks of such views are considered to be the basis for spatial navigation. Two experiments (N = 56) investigated the role of observer perspective on the resulting mental representation when learning a spatial configuration on the computer. Learning in route perspective, which induced the impression of passive navigation through the configuration, was compared with a survey perspective, which consisted of an overview of the whole configuration from one point of view. In accordance with view-based theories, previously seen views could be identified faster and with less error than new views for both perspectives during learning. Recoding the information into the alternative perspective was also possible. If participants were asked to integrate distinct route views into a survey view during learning, the flexibility of the resulting mental representation was greatly increased. This indicates that conscious processes such as imagery play an important role in the integration of spatial knowledge.

The protein Hrb57A of Drosophila melanogaster closely related to hnRNP K from vertebrates is present at sites active in transcription and coprecipitates with four RNA-binding proteins.

The hnRNP K protein is among the major hnRNA-binding proteins with a strong preference for cytidine-rich sequences. We have cloned a Drosophila hnRNP protein closely related to this vertebrate protein. The protein first identified by the monoclonal antibody Q18 is encoded by a gene located in 57A on polytene chromosomes and has been consequently named Hrb57A. The amino acid sequence of the Hrb57A KH domains and their overall organisation in the protein are remarkably similar to the vertebrate proteins. As the hnRNP K in vertebrates the M(r) 55 000 Drosophila Hrb57A/Q18 protein strongly binds to poly(C) in vitro and is ubiquitously present in nuclei active in transcription. On polytene chromosomes it is found in many puffs and minipuffs. Hrb57A/Q18 specifically coprecipitates four other proteins: Hrb87F/P11 a Drosophila hnRNP A1 homologue, the hnRNA-binding protein S5, the RNA recognition motif-containing protein NonA and the RNA-binding zinc finger-containing protein on ecdysone puffs PEP/X4.

Treatment of port-wine stains with a noncoherent pulsed light source: a retrospective study.

OBJECTIVE: We investigated whether a noncoherent intense pulsed light source (IPLS) would be effective in therapy of port-wine stains (PWSs). DESIGN: To evaluate the efficacy in treatment of PWSs with IPLS, a retrospective study was initiated. SETTING: The data were collected by physicians working in private practices and departments of university hospitals and medical centers, respectively. PATIENTS: A total of 37 randomly selected patients with a total of 40 PWSs were included in the study. Clinical PWS characteristics recorded were color and location of the PWS. INTERVENTIONS: All patients were treated with IPLS. MAIN OUTCOME MEASURES: Data collected included treatment parameter (filters, pulse duration, fluence, and pulse sequencing), percentage of clearance, and side effects (purpura, blisters, crusting, altered pigmentation, and scarring). RESULTS: Good and complete (70%-100%) clearance was achieved in 28 of 40 PWSs treated with IPLS. The average number of treatment sessions in PWSs reaching 100% clearance included 4.0 for pink PWSs and 1.5 for red PWSs. The average number of sessions for purple PWSs reaching good clearance (70%-99%) was 4.2 sessions. Parameters used most frequently were 515- and 550-nm cut-off filters, pulse duration of 2.5 to 5.0 milliseconds, and fluences of 24 to 60 J/cm2. Side effects included purpura in 133 (76%), superficial blisters in 14 (8%), and crusting in 35 (20%). Transient pigmentation changes were seen in 10.8% of patients (hypopigmentation in 3 [8.1%], hyperpigmentation in 1 [2.7%]). No scarring was observed. CONCLUSION: Intense pulsed light source presents an effective and safe method for treating PWSs, especially purple PWSs.

Induction of inducible nitric oxide synthase and its corresponding tetrahydrobiopterin-cofactor-synthesizing enzyme GTP-cyclohydrolase I during cutaneous wound repair.

Recent work has suggested a possible role of nitric oxide, a free radical gas, during the wound healing process. In this study we investigated the regulation of inducible nitric oxide synthase (iNOS) and GTP-cyclohydrolase I (GTP-CH I), the rate-limiting enzyme in the biosynthesis of the iNOS cofactor (6R) 5,6,7,8-tetrahydrobiopterin (6-BH4), during the repair process. We found a similar time course of induction of iNOS and GTP-CH I expression, whereas absolute expression levels were different for both genes. Immunohistochemical analysis revealed colocalization of iNOS and GTP-CH I proteins in the wound. Systemic treatment with glucocorticoids significantly altered the expression levels of iNOS and GTP-CH I. Expression of iNOS and GTP-CH I was suppressed by glucocorticoids in normal, and to a much greater extent in wounded skin. Furthermore, a role of nitric oxide as a novel mediator of gene regulation during healing is suggested by the demonstration of nitric oxide-mediated induction of vascular endothelial growth factor expression in keratinocytes. These findings may provide an explanation for the beneficial effects of orally supplemented L-arginine on wound healing, and suggest that a disturbed induction of iNOS and GTP-CH I expression may at least partially underlie the wound healing defect seen in glucocorticoid-treated animals.

Effective treatment of hypertrichosis with pulsed light: a report of two cases.

Hypertrichosis is an often stigmatizing cosmetic problem not only for women but also for male-to-female transsexual patients. The hitherto described therapeutic measures include chemical epilation, razoring, camouflage, electrolysis and thermolysis, and waxing. All of these measures are transient, more or less painful, and may lead to severe side effects (e.g., inflammatory responses and scarring). We report the successful treatment of the perioral and mandibular area of two transsexual patients (male to female), who we treated with a recently introduced intense, pulsed light source--the PhotoDerm VL. Two days after the nearly painless treatment, hair could be epilated easily with forceps. Biopsies of the treated area show an atrophy of the follicles, which can be contributed either to direct thermal injury or to an indirect photothermolytical effect. Six months after the last treatment, there is no local recurrence and no side effects.

The human homologue of a bovine non-selenium glutathione peroxidase is a novel keratinocyte growth factor-regulated gene.

Keratinocyte growth factor is a potent and specific mitogen for different types of epithelial cells, including keratinocytes of the skin. Furthermore, it has been implicated in morphogenetic processes of several organs. To further define the mechanisms of KGF action in the skin, we attempted to identify genes which are regulated by KGF in keratinocytes. Using the differential display RT-PCR technology, a gene was identified which was strongly induced in these cells by treatment with KGF but not with serum growth factors or pro-inflammatory cytokines. Molecular cloning of the full-length cDNA revealed a strong homology of the corresponding gene product with a bovine non-selenium glutathione peroxidase. Upon transfection of COS cells with the full-length cDNA, a 27 kD cytoplasmic protein was obtained which had the expected size of glutathione peroxidase. Expression of the novel gene was detected in normal human skin and at particularly high levels in psoriatic skin, indicating a possible in vivo function of the protein in this tissue. Identification of a peroxidase as a KGF-regulated gene suggests that prevention from oxygen toxicity is a novel and specific mechanism of KGF action.

Complementary DNA sequences of the 24 kDa and 21 kDa subunits of complex I from Neurospora.

We have cloned and sequenced cDNAs coding for two subunits of the peripheral arm of Neurospora crassa complex I. The two polypeptides are synthesized as precursor proteins which are processed to mature forms with predicted molecular masses of 24331 and 20982 Da.

Electrical stimulation of vastus medialis and stretching of lateral thigh muscles in patients with patello-femoral symptoms.

Thirty patients with unilateral patello-femoral symptoms and a hypotrophic vastus medialis muscle were treated with transcutaneous electrical stimulation of the vastus medialis obliquus and stretching of the lateral thigh muscles twice daily for 10 weeks. Before and after treatment the position of the patella at fixed knee flexion angles and the area of the vastus medialis and vastus lateralis muscles were studied by computed tomography. Isokinetic quadriceps torque was registered with a Cybex II Dynamometer. An evaluation with a functional knee score was carried out. The healthy contralateral leg served as control in all the examinations. Clinically two-thirds of the patients had improved after 10 weeks of treatment and this improvement remained at follow-up 3.5 years later. The area of the vastus medialis and the quadriceps torque of the treated leg increased significantly, while the area of the vastus lateralis and the position of patella did not change. We conclude that transcutaneous electrical muscle stimulation of the vastus medialis and stretching of the lateral thigh muscles might be of benefit in patients with patello-femoral symptoms and a hypotrophic vastus medialis. An improvement after 10 weeks of treatment seems to predict a good long-term result.

The PHI (PHI-27)/corticotropin-releasing factor/enkephalin immunoreactive hypothalamic neuron: possible morphological basis for integrated control of prolactin, corticotropin, and growth hormone secretion.

By using the indirect immunofluorescence technique, one and the same neuron in the parvocellular part of the paraventricular nucleus has been shown to stain with antisera against three different peptides: PHI (PHI-27), corticotropin-releasing factor (CRF), and enkephalin. This could explain the well-known parallel increase in plasma prolactin, corticotropin, and growth hormone levels--for example, under certain types of stress--as being due to a concomitant release of PHI-like, CRF-like, and enkephalin-like peptides from the same nerve endings in the median eminence. A hypothetical mechanism for the co-ordinated release of these three anterior pituitary hormones is discussed.

Variations of cationic proteins from eosinophil leukocytes in food intolerance and allergic rhinitis.

Challenge tests were performed in patients with food intolerance and allergic rhinitis to evaluate the usefulness of measurement of the eosinophil cationic protein (ECP) of serum to distinguish different allergic reactions. In one group of patients with food intolerance symptom-induced challenge resulted in a marked decrease of serum-ECP. The number of blood eosinophils decreased simultaneously in some but not all of these patients. In another group of patients with food intolerance serum-ECP displayed peak-like increases followed by a decrease. The decrease in serum-ECP may reflect that consumption of ECP is a result of idiosyncrasy in the target organ. In allergic rhinitis some patients showed an initial peak-like increase of serum-ECP, which was abolished by pretreatment with disodium-cromoglycate but not by pretreatment with antihistamine. Similar results have previously been demonstrated for allergic asthma. The difference obtained in serum-ECP upon challenge in typical reagin-mediated allergy and food intolerance may indicate that the latter is not reagin-mediated. However, the interpretation of data is difficult because of lack of knowledge regarding the turnover in the circulation of ECP.