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1.  A face detection bias for horizontal orientations develops in middle childhood 
Faces are complex stimuli that can be described via intuitive facial features like the eyes, nose, and mouth, “configural” features like the distances between facial landmarks, and features that correspond to computations performed in the early visual system (e.g., oriented edges). With regard to this latter category of descriptors, adult face recognition relies disproportionately on information in specific spatial frequency and orientation bands: many recognition tasks are performed more accurately when adults have access to mid-range spatial frequencies (8–16 cycles/face) and horizontal orientations (Dakin and Watt, 2009). In the current study, we examined how this information bias develops in middle childhood. We recruited children between the ages of 5–10 years-old to participate in a simple categorization task that required them to label images according to whether they depicted a face or a house. Critically, children were presented with face and house images comprised either of primarily horizontal orientation energy, primarily vertical orientation energy, or both horizontal and vertical orientation energy. We predicted that any bias favoring horizontal information over vertical should be more evident in faces than in houses, and also that older children would be more likely to show such a bias than younger children. We designed our categorization task to be sufficiently easy that children would perform at near-ceiling accuracy levels, but with variation in response times that would reflect how they rely on different orientations as a function of age and object category. We found that horizontal bias for face detection (but not house detection) correlated significantly with age, suggesting an emergent category-specific bias for horizontal orientation energy that develops during middle childhood. These results thus suggest that the tuning of high-level recognition to specific low-level visual features takes place over several years of visual development.
PMCID: PMC4459095  PMID: 26106349
face detection; spatial vision; visual development
2.  EUK-207 protects human intestinal microvascular endothelial cells (HIMEC) against irradiation-induced apoptosis through the Bcl2 pathway 
Life sciences  2012;91(15-16):771-782.
To elucidate the signaling mechanisms involved in the protective effect of EUK-207 against irradiation-induced cellular damage and apoptosis in human intestinal microvasculature endothelial cells (HIMEC).
HIMECs were irradiated and treated with EUK-207. Using hydroethidine and DCF-DA fluorescent probe the intracellular superoxide and reactive oxygen species (ROS) were determined. By real-time PCR and western blotting caspase-3, Bcl2 and Bax genes and proteins were analyzed. Proliferation was determined by [3H]-thymidine uptake. Immunofluorescence staining was used for translocation of p65 NFκB subunit.
Key finding
Irradiation increased ROS production, apoptosis, Bax, Caspase3 and NFkB activity in HIMEC and inhibited cell survival/growth/proliferation. EUK-207 restored the endothelial functions, markedly inhibited the ROS, up-regulated the Bcl2 and down-regulated Bax and prevented NFκB caspase 3 activity in HIMEC.
HIMEC provide a novel model to define the effect of irradiation induced endothelial dysfunction. Our findings suggest that EUK-207 effectively inhibits the damaging effect of irradiation.
PMCID: PMC3520131  PMID: 22940617
HIMEC; Irradiation; superoxide dismutase; oxyradical; EUK-207; NFκB
3.  Neuronal Plasticity in the Cingulate Cortex of Rats following Esophageal Acid Exposure in Early Life 
Gastroenterology  2011;141(2):544-552.
Background & Aims
The cingulate cortex (CC) has been reported to be involved in processing pain of esophageal origin. However, little is known about molecular changes and cortical activation that arise from early-life, esophageal acid reflux. Excitatory neurotransmission via activation of the N-methyl-D-aspartate (NMDA) receptor and its interaction with post-synaptic density protein-95 (PSD-95) at the synapse appears to mediate neuronal development and plasticity. We investigated the effect of early-life esophageal acid exposure on NMDA receptor subunits and PSD-95 expression in the developing CC.
We assessed NMDA receptor subunits and PSD-95 protein expression in rostral CC (rCC) tissues of rats exposed to esophageal acid or saline (control), either during post-natal days 7–14 (P7–P14) and/or acutely, at adult stage (P60), using immunoblot and immunoprecipitation analyses.
Compared with controls, acid exposure from P7 to P14 significantly increased expression of NR1, NR2A, and PSD-95, measured 6 weeks after exposure. However, acute exposure at P60 caused a transient increase in expression of NMDA receptor subunits. These molecular changes were more robust in animals exposed to acid neonatally and rechallenged, acutely, at P60. Esophageal acid exposure induced calcium calmodulin kinase II-mediated phosphorylation of the subunit NR2B at Ser1303.
Esophageal acid exposure during early stages of life has long-term effects, because of phosphorylation of the NMDA receptor and overexpression in the rCC. This molecular alteration in the rCC might mediate sensitization of patients with acid-induced esophageal disorders.
PMCID: PMC3152593  PMID: 21616075
brain; developmental neuroscience; pain processing; CamKII
4.  Neonatal Cystitis-Induced Colonic Hypersensitivity in Adult Rats: A Model of Viscero-Visceral Convergence 
The objective of this study was to determine if neonatal cystitis alters colonic sensitivity later in life and to investigate the role of peripheral mechanisms.
Neonatal rats received intravesical zymosan, normal saline, or anesthesia only for three consecutive days (postnatal days 14th–16th). The estrous cycle phase was determined prior to recording the visceromotor response (VMR) to colorectal distension (CRD) in adult rats. Eosinophils and mast cells were examined from colon and bladder tissue. CRD or urinary bladder distension (UBD)-sensitive pelvic nerve afferents (PNAs) were identified and their responses to distension were examined. The relative expression of N-methyl-D-aspartic acid (NMDA) NR1 subunit in the L6-S1 spinal cord was examined using Western blot.
The VMR to CRD (≥10mmHg) in the neonatal zymosan group was significantly higher than control in both the diestrus, estrus phase and in all phases combined. There was no difference in the total number of eosinophils, mast cells or number of degranulated mast cells between groups. The spontaneous firing of UBD, but not CRD-sensitive PNAs from the zymosan rats was significantly higher than the control. However, the mechanosensitive properties of PNAs to CRD or UBD were no different between groups (p > 0.05). The expression of spinal NR1 subunit was significantly higher in zymosan-treated rats compared to saline treated rats (p <0.05).
Neonatal cystitis results in colonic hypersensitivity in adult rats without changing tissue histology or the mechanosensitive properties of CRD-sensitive PNAs. Neonatal cystitis does results in overexpression of spinal NR1 subunit in adult rats.
PMCID: PMC3117950  PMID: 21592255
cystitis; visceral hyperalgesia; neonatal; viscero-visceral convergence

Results 1-4 (4)