RESUMEN
Recent studies have highlighted the significance of the spindle midzone - the region positioned between chromosomes - in ensuring proper chromosome segregation. By combining advanced 3D electron tomography and cutting-edge light microscopy we have discovered a previously unknown role of the regulation of microtubule dynamics within the spindle midzone of C. elegans. Using Fluorescence recovery after photobleaching and a combination of second harmonic generation and two-photon fluorescence microscopy, we found that the length of the antiparallel microtubule overlap zone in the spindle midzone is constant throughout anaphase, and independent of cortical pulling forces as well as the presence of the microtubule bundling protein SPD-1. Further investigations of SPD-1 and the chromokinesin KLP-19 in C. elegans suggest that KLP-19 regulates the overlap length and functions independently of SPD-1. Our data shows that KLP-19 plays an active role in regulating the length and turn-over of microtubules within the midzone as well as the size of the antiparallel overlap region throughout mitosis. Depletion of KLP-19 in mitosis leads to an increase in microtubule length in the spindle midzone, which also leads to increased microtubule - microtubule interaction, thus building up a more robust microtubule network. The spindle is globally stiffer and more stable, which has implications for the transmission of forces within the spindle affecting chromosome segregation dynamics. Our data shows that by localizing KLP-19 to the spindle midzone in anaphase microtubule dynamics can be locally controlled allowing the formation of a functional midzone.
RESUMEN
OBJECTIVE: We aimed to assess the association between cord blood brain-derived neurotrophic factor (BDNF) concentration and maternal depression during pregnancy. METHODS: A total of 48 pregnant women, admitted for elective caesarean section to Department of Obstetrics and Gynecology, The Konya Research and Training Hospital and Konya Necmettin Erbakan University Meram Medical Faculty, were included in this study. The study group included 23 women diagnosed as having depression during pregnancy and the control group included 25 pregnant women who did not experience depression during pregnancy. RESULTS: The groups had similar sociodemographic characteristics. Cord blood BDNF concentration was significantly lower in babies born to mothers with major depression as compared with those in the control group. We didn't find any correlation between the umbilical cord blood BDNF levels and BDI scores. CONCLUSION: The results suggest that the existence of major depression in pregnant women may negatively affect fetal circulating BDNF levels.