Neuroscience
-
Inflammation is an important event in ischemic injury. These immune responses begin with the expression of pro-inflammatory genes modulating transcription factors, such as nuclear factor-κB (NF-κB), activator protein-1 (AP-1), and signal transducers and activator of transcription-1 (STAT-1). The 70-kDa heat shock protein (Hsp70) can both induce and arrest inflammatory reactions and lead to improved neurological outcome in experimental brain injury and ischemia. ⋯ The results showed that heat stress led to Hsp70 overexpression which rendered neuroprotection after ischemia-like injury. Overexpression Hsp70 also interrupts the phosphorylation of IκB, JNK and p38 and blunts DNA binding of their transcription factors (NF-κB, AP-1 and STAT-1), effectively downregulating the expression of pro-inflammatory genes in heat-pretreated astrocytes. Taken together, these results suggest that overexpression of Hsp70 may protect against brain ischemia via an anti-inflammatory mechanism by interrupting the phosphorylation of upstream of transcription factors.
-
The progressive loss of memory and autonomy of Alzheimer's Disease (AD) patients, together with their characteristic behavioral and psychological symptoms, subjects their family caregivers to chronic stress. Several studies indicate that these caregivers are predisposed to cognitive impairments, but the physiological correlates of these alterations remain to be elucidated. ⋯ This study showed that caregivers' cognitive impairment is related with alterations on cortisol/DHEA ratios, and that chronic stress experienced by these subjects has the potential to alter their BDNF levels.
-
Oral contraceptives (OCs) affect mood in some women and may have more subtle effects on emotional information processing in many more users. Female carriers of mineralocorticoid receptor (MR) haplotype 2 have been shown to be more optimistic and less vulnerable to depression. ⋯ Carriers of MR haplotype 2 may be less sensitive to depressogenic side-effects of OCs.
-
The aim of this study was to examine how feedback, or its absence, affects children with Developmental Coordination Disorder (DCD) during a visuo-manual tracking task. This cross-sectional study included 40 children with DCD and 40 typically developing (TD) children between 6 and 10 years old. Participants were required to track a target moving along a circular path presented on a monitor by moving an electronic pen on a digitizing tablet. ⋯ The mean tracking speed of the DCD group exceeded the speed at which the target rotated which was attributed to accelerations and decelerations made during tracking. This suggests that children with DCD have significant difficulties in visuo-manual tracking especially when visual feedback is reduced. It appears that their impaired ability to predict together with impairments in fine-tuning arm movements may be responsible for poor performance in the intermittently occluded visuo-manual tracking task.
-
The calsyntenins are atypical members of the cadherin superfamily that have been implicated in learning in Caenorhabditis elegans and memory formation in humans. As members of the cadherin superfamily, they could mediate cell-cell adhesion, although their adhesive properties have not been investigated. As an initial step in characterizing the calsyntenins, we have cloned clstn1, clstn2 and clstn3 from the zebrafish and determined their expression in the developing zebrafish nervous system. ⋯ Each of the ectodomains mediates homophilic interactions through two, amino-terminal cadherin repeats. In bead sorting assays, the calsyntenin ectodomains do not exhibit homophilic preferences. These data support the idea that calsyntenins could either act as adhesion molecules or as diffusible, homophilic or heterophilic ligands in the vertebrate nervous system.