Postnatal neurogenesis in the hippocampal dentate gyrus and subventricular zone of the Goettingen minipig.

Postnatal neurogenesis is currently viewed as important for neuroplasticity and brain repair. We are, therefore, interested in animal models for neuroimaging of postnatal neurogenesis. A recent stereological study found an age-dependent increase in the number of neurons and glial cells in the neocortex of G\uf6ttingen minipigs, suggesting that this species may be characterized by a prolonged postnatal neurogenesis. Since there is no direct evidence on this issue, the goal of our study was to quantify cell proliferation in the two major neurogenic regions of the postnatal brain - the subventricular zone of the lateral ventricle (SVZ) and the hippocampal dentate gyrus (DG) - at two separate points during the lifespan of the minipig. G\uf6ttingen minipigs aged 6-7 and 32 weeks were injected with bromodeoxyuridine (BrdU), a marker of cycling cells, and killed after 2h. We found BrdU-positive cells numbering 165,000 in the SVZ and 35,000 in the DG at 6-7 weeks and 66,000 in the SVZ and 19,000 in the DG at 32 weeks-of-age. Stereology showed a 60% increase in the total number of DG granule cells between 6-7 and 32 weeks-of-age. Our findings show a continued postnatal neurogenesis in the major neurogenic regions of G\uf6ttingen minipigs, thereby providing a potential animal model for studies aimed at examining ongoing neurogenesis in the living brain with molecular neuroimaging technology

Obstetric outcome and incidence of congenital anomalies in 2351 IVF/ICSI babies

PURPOSE: The aim of this study was to provide a comprehensive follow-up of fetal and perinatal outcome and the incidence of congenital anomalies in babies born after fresh embryo transfers compared to those conceived spontaneously in infertile couples. METHODS: Retrospective comparative analysis of all clinical pregnancies from fresh cleavage-stage embryo transfer cycles (IVF and ICSI) compared with infertile patients who conceived spontaneously in the same time period (control). Congenital anomalies were classified following the European Surveillance of Congenital Anomalies (EUROCAT) classification. RESULTS: A total of 2414 assisted reproductive technology (ART) pregnancies were compared to 582 spontaneous conceptions in the control infertile group representing 2306 deliveries. No significant differences were found in pregnancy outcome between the two groups (delivery rate, abortion rate, ectopic pregnancies, medical abortions for fetal anomalies, single and twins mean gestational age, and weight at delivery). A significant difference (p < 0.001) was found in the twin (21.3 vs 2.3 %) and triplet rates (2.3 vs 0 %). A total of 2351 babies were delivered in the ART group and 449 in the control group. A total of 90 babies (3.8 %) were diagnosed with a major congenital anomaly in the ART group and 15 (3.3 %) in the control group (p = ns). The overall rate of major congenital anomalies (105/2800) in ART and spontaneous pregnancies in infertile couples was significantly higher when compared to the EUROCAT 2.0 versus 3.75 % (p = 0.0002). DISCUSSION: Babies born after ART treatments and from spontaneous conception in infertile couples had rates of congenital anomalies higher than those recorded by the EUROCAT. However, the rates of anomalies were not different within the infertile population whether conceived by ART or spontaneously. These data suggest that the diagnosis of infertility in itself is the common denominator for the increase in the rates of anomalies seen in both ART and spontaneous conceptions

QUALITY OF THE TASKS IN THE NEW TURKISH ELEMENTARY MATHEMATICS TEXTBOOKS: THE CASE OF PROPORTIONAL REASONING

This study examines new Turkish elementary school mathematics textbooks to provide perspectives on the quality of the tasks related to the proportion concept and the ways they are presented. Tasks were analysed for several dimensions with a particular focus on their level of cognitive demands (LCD). Tasks were distinguished in two groups in terms of LCD: lower-level demand and higher-level demand. The findings revealed that 75 % of the tasks were related to higher-level demand in that they requested a certain level of interpretation, required connecting knowledge and procedures related to each other, demanded responses with some explanation and reinforced students' non-algorithmic thinking. Only 25 % of the tasks were related to a lower-level demand, and these tasks could be resolved by recalling and implementing rules, procedures and factual knowledge without reflecting upon the meaning behind them. Most of the tasks were presented in multiple representations and framed in non-mathematical contexts. All these task characteristics indicate that the new elementary school textbooks have the capacity to promote students' proportional reasoning. The findings also inform the international community about crucial aspects of the curriculum reforms in Turkey and provide suggestions for teachers and textbook writers concerning the quality of the tasks and their selection and implementation in the classrooms