Brain research
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Intrauterine growth restriction (IUGR) is associated with a high risk of abnormal neurodevelopment. Underlying neuroanatomical substrates are partially documented. We hypothesized that at 12 months preterm infants would evidence specific white-matter microstructure alterations and gray-matter differences induced by severe IUGR. ⋯ These data suggest that IUGR differentially affects gray and white matter development preferentially affecting gray matter. At 12 months IUGR is associated with a specific set of structural gray-matter decrements. White matter follows an unusual developmental pattern, and is apparently affected by IUGR and prematurity combined.
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N-hydroxy-N-(4-butyl-2-methylphenyl) formamidine (HET0016) is a specific 20-hydroxyeicosatetraenoic acid (20-HETE) inhibitor which was first synthesized in 2001. It has been demonstrated that HET0016 reduces cerebral infarction volume in rat middle cerebral artery occlusion (MCAO) models. However, little is known about the role of HET0016 in the blood-brain barrier (BBB) dysfunction after cerebral ischemia/reperfusion (I/R) injury. ⋯ Western blot showed that HET0016 suppressed the activation of MMP-9 and JNK pathway but restored the expression of Claudin-5 and ZO-1. In conclusion, these results suggest that HET0016 protects BBB dysfunction after I/R by regulating the expression of MMP-9 and tight junction proteins. Furthermore, inhibition of oxidative stress and JNK pathway may be involved in this protecting effect.
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The aim of the present study was to identify, whether and how oral hormonal contraceptives (OCs) alter women's number processing. Behavioral performance and brain activation patterns (BOLD-response) of 14 OC-users were evaluated during two distinct numerical tasks (number comparison, number bisection) and compared to 16 men (high testosterone), and 16 naturally cycling women, once during their follicular (low hormone levels) and once during their luteal cycle phase (high progesterone). For both tasks, reliable sex differences and menstrual cycle dependent modulation have previously been described. ⋯ Our findings suggest that OC-users resemble follicular women in their behavioral performance, but show male-like brain activation patterns during both tasks. Analysis of brain-behavior relationships suggests that OC-users differ from naturally cycling women in the way they recruit their neural resources to deal with challenges of the tasks. We conclude that OCs, which are used by 100 million women worldwide, may have profound effects on cognition that have not been recognized so far.
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This study addressed the engagement of attention and working memory, as inferred from electrophysiological measurements, in the processing of small sets of objects. We recorded N2pc and CDA, two lateralized components of the EEG signal associated respectively with individuation and visual working memory, while participants enumerated a variable number (1-9) of uniquely colored targets among distractors. ⋯ However, individual differences in the enumeration efficiency were correlated only with the individual variation in the N2pc modulations. The results suggest that the constraints of the attentional individuation system play a significant role in the occurrence of the subitizing phenomenon.
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The endogenous opioid enkephalin is known to inhibit spinal nociceptive transmission. Here we investigated activation of spinal enkephalinergic neurons by determining the proportions of c-Fos expressing (activated) spinal neurons that were enkephalinergic after different acute and chronic peripheral nociceptive stimuli. The number of c-Fos-activated neurons in the dorsal horn was increased after hind paw injection of capsaicin, formalin or complete Freund's adjuvant (CFA, 1.5 hrs - 4 days). ⋯ Combining all acute (=2 hrs) versus chronic (≥20 hrs) treatment groups, there was a significant decrease in the percentage of activated neurons that were enkephalinergic in superficial layers, but a significant increase in the deeper layers of the dorsal horn in the chronic treatment group. It is concluded that the overall percentage of c-Fos activated neurons that contained enkephalin was not significantly different between acute and chronic pain phases. However, the shift in localization of these neurons within the spinal dorsal horn indicates a noxious stimulus directed activation pattern.