Petra Jansen

Splicing Factor SRp30c Interaction with Y-box Protein-1 Confers Nuclear YB-1 Shuttling and Alternative Splice Site Selection

The multifunctional DNA- and RNA-associated Y-box protein 1 (YB-1) specifically binds to splicing recognition motifs and regulates alternative splice site selection. Here, we identify the arginine/serine-rich SRp30c protein as an interacting protein of YB-1 by performing a two-hybrid screen against a human mesangial cell cDNA library. Co-immunoprecipitation studies confirm a direct interaction of tagged proteins YB-1 and SRp30c in the absence of RNA via two independent protein domains of YB-1. A high affinity interaction is conferred through the N-terminal region. We show that the subcellular YB-1 localization is dependent on the cellular SRp30c content. In proliferating cells, YB-1 localizes to the cytoplasm, whereas FLAG-SRp30c protein is detected in the nucleus. After overexpression of YB-1 and FLAG-SRp30c, both proteins are co-localized in the nucleus, and this requires the N-terminal region of YB-1. Heat shock treatment of cells, a condition under which SRp30c accumulates in stress-induced Sam68 nuclear bodies, abrogates the co-localization and YB-1 shuttles back to the cytoplasm. Finally, the functional relevance of the YB-1/SRp30c interaction for in vivo splicing is demonstrated in the E1A minigene model system. Here, changes in splice site selection are detected, that is, overexpression of YB-1 is accompanied by preferential 5′ splicing site selection and formation of the 12 S isoform.

Surgical Mesh as a Scaffold for Tissue Regeneration in the Esophagus

Background: Textiles in the form of surgical meshes are widely used in hernia surgery. Their porous structure allows tissue infiltration to incorporate the fabric for complete healing and device stabilization. This study was aimed to reconstitute the esophageal wall and to investigate the functional and histological consequences of a new, non-absorbable polyvinylidene fluoride (PVDF) mesh and an absorbable polyglactin 910 (Vicryl®) mesh. Methods: Semicircular esophageal defects of 0.5 × 1 cm were created 2 cm proximal of the cardia in 10 rabbits. This gap was bridged using either polyglactin 910 or PVDF and additionally covered by omental wrapping. The clinical outcome was observed by clinical observation, regular esophagoscopies and X-ray contrast medium examinations. Local tissue regeneration was verified by light microscopy and immunohistochemistry. Results: After an observation period of 3 months we found no anastomotic strictures, complete mucosal regeneration, minimal inflammation reaction and initial regeneration of the muscle layer for the PVDF group. Within the polyglactin 910 group, three patch failures with consecutive anastomotic leakage occurred. Conclusion: The results indicate that PVDF mesh structure gives the opportunity of local tissue regeneration in the esophagus. Though re-epithelialization and muscle cell ingrowth could be detected for absorbable polyglactin 910 mesh, this implant was accompanied by a high and early rate of anastomotic leakage.

Mental rotation in female fraternal twins: Evidence for intra-uterine hormone transfer?

Men outperform women in mental rotation by about one standard deviation. Prenatal exposure to testosterone has been suggested as one cause. In animals it has been shown that a female fetus located between two male ones is exposed to higher levels of testosterone. It is still unclear whether intra-uterine hormone transfer exists in humans. Therefore, the influence of an intra-uterine presence of a male co twin was studied in female fraternal twins (N=200). Women with a male co-twin outperformed women with a female co-twin by about a third standard deviation. In a no-twin control group (N=200), performance of women with a slightly older sibling did not depend upon the siblings sex. These findings provide preliminary support for the theory of an influence of prenatal testosterone on mental rotation performance.

Spatial Knowledge Acquisition in Younger and Elderly Adults A Study in a Virtual Environment

This study investigated the process of spatial knowledge acquisition in younger adults (20-30 years), middle-aged adults (40-50 years), and older adults (60-70 years) in a desktop virtual environment, where participants learned a way through a virtual maze, had to recall landmarks that were present in the maze, and had to draw an overview of the maze. The results revealed a general decline in spatial memory of the elderly, that is, in the time needed to learn a new route, in the retrieval of landmarks from memory (landmark knowledge), and in the ability to draw a map (configurational knowledge). When the route with landmarks was perfectly learned, however, there was no age dependent difference in finding the correct route without landmarks in the virtual maze (retrieval of route knowledge). Therefore, we conclude that not all aspects of spatial knowledge acquisition and spatial memory degrade with increasing age during adulthood.

The Relation Between Motor Development and Mental Rotation Ability in 5- to 6-Year-old Children

This study investigated the relation between motor development, intelligence and mental rota tion ability in 5 to 6-year-old children. 80 children performed a standardized motor test (MOT 4-6), a paper-pencil mental rotation test (BIRT) and a non-verbal reasoning test (CPM). A multiple regression analysis revealed that intelligence and motor control abilities were significant and independent predictors of mental rotation performance.

Gender Differences in Mental Rotation Across Adulthood

Although gender differences in mental rotation in younger adults are prominent in paper-pencil tests as well as in chronometric tests with polygons as stimuli, less is known about this topic in the older age ranges. Therefore, performance was assessed with the Mental Rotation Test (MRT) paper-pencil test as well as with a computer-based two-stimulus same-different task with polygons in a sample of 150 adults divided into three age groups, 20–30, 40–50, and 60–70 years. Performance decreased with age, and men outperformed women in all age groups. The gender effect decreased with age in the MRT, possibly due to a floor effect. Gender differences remained constant across age, however, in the error rates of the computer-based task.

Effects of physical activity on executive function and motor performance in children with ADHD

Children with Attention-Deficit/Hyperactivity Disorder (ADHD) often show major deficits in motor and cognitive abilities. Pharmacological treatment is commonly used to reduce ADHD symptoms. However, non-pharmacologic treatment methods would be preferred by parents, children and psychiatrists. Physical activity (PA) has been demonstrated to improve cognitive functioning in healthy populations. It can be hypothesized that there are similar beneficial effects in children with ADHD, however, very little is known about this issue. The purpose of the present study was to determine whether PA improves cognitive performance in children with ADHD. A total of 43 children with ADHD (32 boys and 11 girls) aged between seven and 12 years took part in the study. To investigate whether potential effects on executive functioning depend on the kind of PA, two different 12-week training programs were implemented. The study-design consisted of two experimental groups (EG1, n=13; EG2, n=14) and a wait-list control group (CG, n=16). Participants in EG1 took part in a training which focused on the abilities ball handling, balance and manual dexterity. Participants in EG2 group were trained in sports without a specific focus. The children in the CG group received no intervention. Participants completed assessments of working memory (WM) and motor performance before, immediately after the first training week and one week after the last session. After the 12-week intervention period, several measures of the EG1 and EG2s significantly improved over time. Furthermore, between group comparisons demonstrated significant improvements in both EG1 and EG2 compared to the CG in variables assessing WM performance and motor performance. These findings support the hypothesis that long-term PA has a positive effect on executive functions of children with ADHD, regardless of the specificity of the PA. The outcomes indicated that regular PA can be used as a complementary or alternative non-pharmacologic treatment for ADHD.

Impaired mental rotation performance in overweight children

Overweight children seem to have cognitive impairment. Since there is a relationship between motor and visual-spatial ability and because of the reduced motor abilities of overweight children we assumed that these children might show an impaired mental rotation performance. Sixteen overweight children (10 years of age) and 16 control children (10 years of age) were matched by age, gender, and socio-economic status. Each participant completed a general intelligence test, a motor test, and a chronometric mental rotation test. The results show differences in both motor ability and mental rotation accuracy. Overweight children made more errors when the rotation task was difficult compared to normal weight children. This study gives a clue to overweight childrens problems in spatial cognitive tasks.

Polymeric meshes induce zonal regulation of matrix metalloproteinase-2 gene expression by macrophages and fibroblasts

Matrix metalloproteinase‐2 (MMP‐2) is a key regulator in wound healing that orchestrates tissue remodeling. In the present study the spatial and temporal distribution of MMP‐2 gene transcription, protein synthesis, and enzymatic activity were analyzed following polymeric mesh (polyglactin, polypropylene) im‐plantation in transgenic reporter mice harboring MMP‐2 regulatory sequences ‐1686/+423 or ‐1241/ +423. Polymers induced MMP‐2 promoter activity in macrophages within the foreign body granuloma via sequences ‐ 1686/+ 423 with concomitantly up‐regulated protein synthesis and enzymatic activity. Macro‐phages distant from mesh filaments exhibited low MMP‐2 expression levels. Fibroblasts surrounding mesh material displayed strong MMP‐2 gene transcription independent of the included promoter sequences, whereas fibroblasts without close contact to mesh material had low MMP‐2 synthesis rates due to silencing activity of sequences ‐1686/ ‐1241. In vitro studies support a cellular crosstalk concept, as macrophages trans‐repressed MMP‐2 gene transcription in fibroblasts. The zonal and cell‐specific regulation of MMP‐2 gene transcription illuminates an intimate cellular crosstalk in foreign body reaction that may provide a new approach for mesh modification.—Jansen, P. L., Kever, M., Rosch, R., Krott, E., Jansen, M., Alfonso‐Jaume, A., Dooley, S., Klinge, U., Lovett, D. H., Mertens, P. R. Polymeric meshes induce zonal regulation of matrix metalloproteinase‐2 gene expression by macrophages and fibroblasts. FASEB J. 21, 1047–1057 (2007)

Mental Rotation Performance in Male Soccer Players

It is the main goal of this study to investigate the visual-spatial cognition in male soccer players. Forty males (20 soccer players and 20 non-athletes) solved a chronometric mental rotation task with both cubed and embodied figures (human figures, body postures). The results confirm previous results that all participants had a lower mental rotation speed for cube figures compared to embodied figures and a higher error rate for cube figures, but only at angular disparities greater than 90°. It is a new finding that soccer–players showed a faster reaction time for embodied stimuli. Because rotation speed did not differ between soccer-players and non-athletes this finding cannot be attributed to the mental rotation process itself but instead to differences in one of the following processes which are involved in a mental rotation task: the encoding process, the maintanence of readiness, or the motor process. The results are discussed against the background of the influence on longterm physical activity on mental rotation and the context of embodied cognition.