Natural activation of caspase-3 is required for the development of operant behavior in postnatal ontogenesis

We have previously demonstrated transient increases in caspase-3 activity in the hippocampus of rat pups from age 17 days. We report here our studies on the effects of inhibition of caspase-3 during this period on the acquisition of a two-way avoidance reaction. Rat pups received intracerebroventricular doses of the caspase-3 inhibitor Z-DEVD-FMK On postnatal day 18. Control animals of the same age received the inactive peptide Z-FA-FMK or isotonic saline solution. Inhibition of caspase-3 during the period of its natural activation in the hippocampus during early ontogenesis was found to impair the development of operant behavior in rats. This was apparent as a reduction in the efficiency of learning during acquisition of active avoidance reactions and decreases in the numbers of intersignal reactions. Administration of the inhibitor had no specific action on the types of conditioned reflex activity less associated with operant learning. Thus, there were no differences between the experimental and control groups in the numbers of emotional reactions to the conditioned stimulus. The number of orientational-investigative conditioned reactions also showed no change after administration of Z-DEVD-FMK. On the background of the reduction in the efficiency of the acquisition of the conditioned active avoidance reflex, the number of incomplete acts, in contrast to other types of conditioned reactions, increased significantly after administration of Z-DEVD-FMK, which is evidence for the persistence of the ability to form associative connections between activation of the conditioned signal and the need to move to the other sector. The difficulty in these animals arose at the decision-taking stage on choosing the appropriate form of behavior. Changes in orientational-investigative behavior were not associated with inhibition of caspase-3 during the critical period of development, as the effects of Z-DEVD-FMK and Z-FA-FMK were similar. Translated from Zhurnal Vysshei Nervnoi Deyatel'nosti imeni I. P. Pavlova, Vol. 57, No. 6, pp. 702–711, November–December, 2007.     

Condylar process contributes to mandibular asymmetry: In vivo 3D MRI study

The purpose of this study was to investigate the differences in mandibular morphology between the deviated and nondeviated sides in patients with noncongenital skeletal mandibular asymmetry. Divergences from control values were assessed to determine which region of the mandible contributes most to mandibular asymmetry. We measured various dimensions of the mandible in 20 young patients and 20 controls using noninvasive high‐quality three‐dimensional (3D) volumetric magnetic resonance imaging. Mandibular dimensions including the length of the condylar process were significantly greater on the nondeviated side of patients than the deviated side. Measurements of the deviated side were similar to control values, but measurements of the nondeviated side including condylar process length differed significantly from control values. These findings strongly suggest that overgrowth of the condylar process on the nondeviated side in these patients results in mandibular asymmetry, and therefore needs attention in orthodontic treatment, orthognathic surgery, and follow‐up. Clin. Anat. 585–591, 2014. © 2013 Wiley Periodicals, Inc.     

The receptor‐like kinases GSO1 and GSO2 together regulate root growth in arabidopsis through control of cell division and cell fate specification

COVER PHOTOGRAPH: Confocal image of a median optical section through a heart stage Arabidopsis embryo expressing the epidermalmarker pATML1:: HTA6‐GFP and counterstained with propidium iodide. From The receptor‐like kinases GSO1 and GSO2 together regulate root growth in Arabidopsis through control of cell division and cell fate specification; Racolta et al, Developmental Dynamics 243:257–278.     

Slitrk gene duplication and expression in the developing zebrafish nervous system

Results : As a prelude to examining the functional roles of Slitrks, we identified eight slitrk orthologs in zebrafish and observed that seven of the eight orthologs were actively transcribed in the nervous system at embryonic, larval, and adult stages. Similar to previous findings in mice and humans, zebrafish slitrks exhibited unique but overlapping spatial and temporal expression patterns in the developing brain, retina, and spinal cord. 相似文献