Brain activity associated with memory and cognitive function during jaw-tapping movement in healthy subjects using functional magnetic resonance imaging.

OBJECTIVE: To determine whether jaw-tapping movement, a classically described as an indication of personal well-being and mental health, stimulates the memory and the cognitive regions of the brain and is associated with improved brain performance. METHODS: Twelve healthy right-handed female subjects completed the study. Each patient performed a jaw-tapping task and an n-back task during functional magnetic resonance imaging (fMRI). The subjects were trained to carry out the jaw-tapping movement at home twice a day for 4 weeks. The fMRI was repeated when they returned. RESULTS: During the first and second jaw-tapping session, both sides of precentral gyrus and the right middle frontal gyrus (BA 6) were activated. And during the second session of the jaw-tapping task, parts of frontal lobe and temporal lobe related to memory function were more activated. In addition, the total percent task accuracy in n-back task significantly increased after 4 weeks of jawtapping movement. After jaw-tapping training for 4 weeks, brain areas related to memory showed significantly increased blood oxygen level dependent signals. CONCLUSION: Jaw-tapping movement might be a useful exercise for stimulating the memory and cognitive regions of the brain.

Sex differences in amygdala subregions: evidence from subregional shape analysis.

Each subregion of the amygdala is characterized by a distinct cytoarchitecture and function. However, most previous studies on sexual dimorphism and aging have assessed differences in the structure of the amygdala at the level of the amygdala in its entirety rather than at the subregional level. Using an amygdala subregional shape analysis, we investigated the effects of sex, age, and the sex × age interaction on the subregion after controlling for intracranial volume. We found the main effect of age in the subregions and the effect of sex in the superficial nucleus, which showed that men had a larger mean radius than women. We also found a sex × age interaction in the centromedial nucleus, in that the radius of the centromedial nucleus showed a steeper decline with age in women compared with men. Regarding the amygdala volume as a whole, we found only an age effect and did not find any other significant difference between genders. The sex difference in the amygdala subregion and its relevance to the circulating gonadal hormone were discussed.

Proteomic analysis of tumor tissue in CT-26 implanted BALB/C mouse after treatment with ascorbic acid.

Tumor establishment and penetration consists of a series of complex processes involving multiple changes in gene expression and protein modification. Proteome changes of tumor tissue were investigated after intraperitoneal administration of a high concentration of ascorbic acid in BALB/C mice implanted with CT-26 cancer cells using two-dimensional gel electrophoresis and mass spectrometry. Eighteen protein spots were identified whose expression was different between control and ascorbic acid treatment groups. In particular, eukaryotic translation initiation factor 3 subunit 1, nucleophosmin, latexin, actin-related protein 2/3 complex subunit 5, M2-type pyruvate kinase, vimentin, tumor protein translationally-controlled 1, RAS oncogene family Ran, plastin 3 precursor, ATPase, Rho GDT dissociation inhibitor ß, and proteasome activator subunit 2 expression were quantitatively up-regulated. The increase in the level of these proteins was accompanied by an increase in mRNA level. The cytoskeleton protein actin, vimentin, and tumor protein translationally-controlled 1 showed quantitative expression profile differences. A change in actin cytoskeleton distribution, functionally relevant to the proteome result, was observed after treatment with ascorbic acid. These results suggest a previously undefined role of ascorbic acid in the regulation of cytoskeleton remodeling in tumor tissues.

An fMRI study of neuronal specificity of an acupoint: electroacupuncture stimulation of Yanglingquan (GB34) and its sham point.

The neuronal specificity of acupoints has not been entirely supported by the results of fMRI studies. The objective of this study was to investigate the neuronal specificity of an acupoint with electroacupuncture stimulation (EAS) using functional magnetic resonance imaging (fMRI). Functional MR imaging of the entire brain was performed in 12 normal healthy subjects during EAS of GB34 (Yanglingquan) and its sham point over the left leg in counter-balanced order. Anatomically, both GB34 and its sham point belong to the L5 spinal segment. EAS at the left GB34 specifically activated the right putamen, caudate body, claustrum, thalamus, cerebellum, as well as the left caudate body, ventral lateral thalamus, and cerebellum, all related to motor function. EAS at the sham point of the left GB34 specifically activated the right BA6, BA8, BA40, BA44, thalamus, as well as the left thalamus and cerebellum. Taken together, these findings suggest that EAS at an acupoint and its sham point, in the same spinal segment, induced specific cerebral response patterns. These findings support neuronal specificity of the acupoint studied. EAS at GB34 appears to be more related to motor function than EAS at its sham point, suggesting specificity of the GB34 acupoint. The results of this study provide neurobiological evidence for the existence of acupoint specificity, although further studies are necessary to better understand this phenomenon.