Spatially filtered magnetoencephalographic analysis of cortical oscillatory changes in basic brain rhythms during the Japanese 'Shiritori' Word Generation Task

BACKGROUND: 'Shiritori' (capping verses) is a traditional Japanese word generation game, and is very familiar to native Japanese speakers. The shiritori task is expected to more strongly activate temporal language-related regions than conventional word generation to letters because of its characteristic way to make cue letters. OBJECTIVES: The aim of this study was to examine the cortical oscillatory changes in basic brain rhythms during silently performing a shiritori task. METHODS: Using synthetic aperture magnetometry (SAM) analysis of magnetoencephalography, we estimated the tomographic distributions of the statistically significant differences of the power in the alpha and beta frequency bands between the resting and the task periods. RESULTS: Significant event-related desynchronization (ERD) in the 8- to 25-Hz band, thought to reflect neural activation, was localized within task-related cortical regions with left-side dominance. The significant ERDs were estimated in both the frontal and temporal language-related regions encompassing Broca's and Wernicke's areas, although previous neuroimaging studies using word generation to letters showed neural activation predominantly in frontal regions. CONCLUSIONS: Our results show the potential of SAM analysis for reliable brain mapping of language processing, and suggest that the shiritori task might be more suitable for examining the language-related network in the brain than conventional word generation to letters.     

The benefits of laparoscopically assisted distal gastrectomy for obese patients

Background  

In Japan, the number of obese patients with gastric cancer is increasing. This study aimed to evaluate the advantages of laparoscopically assisted distal gastrectomy (LADG) for obese patients relative to those of conventional distal gastrectomy (DG).     

Could the eZ-SCOPE AN Gamma Camera Replace Intraoperative Measurement of iPTH for PHPT?

Intraoperative intact parathyroid hormone (iPTH) measurements have been proposed as an effective assay in surgery for primary hyperparathyroidism (PHPT). We have demonstrated the efficiency of the use of a hand-held gamma camera, eZ-SCOPE AN, with technetium-99m sestamibi (Tc-MIBI) scintigraphy for navigation surgery for PHPT. The aim of this preliminary study was to assess the possibility that the eZ-SCOPE AN can replace the measurement of intraoperative iPTH in surgery for PHPT. Sixteen consecutive patients with documented primary hyperparathyroidism underwent surgery using this compact camera. iPTH was routinely measured preoperatively and 10 minutes after the complete removal of adenoma. All patients had a well-defined parathyroid lesion identified on preoperative Tc-MIBI. The eZ-SCOPE revealed hyperfunctioning parathyroid glands in all cases. iPTH levels were decreased in all cases after the removal of adenomas. Our results suggest that this gamma camera is useful for confirming complete resection of endocrinologically active tissue in surgery for PHPT. In selective patients with scan-positive cases identified by preoperative Tc-MIBI, the eZ-SCOPE may replace the intraoperative iPTH assay in surgery for PHPT.     

Clinical significance of mucin phenotype, beta-catenin and matrix metalloproteinase 7 in early undifferentiated gastric carcinoma

BACKGROUND: The aim of this study was to examine the clinical significance of mucin phenotypes of early undifferentiated gastric carcinoma, and to identify variables that might be used to select patients suitable for minimally invasive surgery. METHODS: A total of 129 patients with early undifferentiated gastric carcinoma were studied. The mucin phenotype was determined immunohistochemically using markers for M1, apomucin (MUC) 6 and MUC2. Tumours were classified into gastric (G), intestinal, gastrointestinal (GI) or unclassified type. Undifferentiated carcinomas were classified into signet-ring cell carcinoma (SIG) and non-SIG. The immunoreactivity of matrix metalloproteinase (MMP) 7 and beta-catenin was also investigated. RESULTS: GI-type tumours more commonly expressed non-SIG than SIG histology. The GI phenotype was associated with a higher incidence of submucosal invasion, lymphatic invasion, MMP-7 expression and nuclear accumulation of beta-catenin than the G type. Non-SIG histology, and the combination of GI type and nuclear accumulation of beta-catenin were independent predictors of submucosal invasion. The combination of GI type and MMP-7 expression independently predicted lymphatic invasion. MMP-7 expression correlated with lymph node metastasis. CONCLUSION: GI-type early undifferentiated carcinomas and those with non-SIG histology had increased potential for invasion and metastasis. GI type, MMP-7 expression and nuclear accumulation of beta-catenin might prove useful markers in the selection of patients for less invasive surgery.     

Functional anatomy of the basal ganglia in X-linked recessive dystonia-parkinsonism

Dystonia is a neurological syndrome characterized by sustained muscle contractions that produce repetitive twisting movements or abnormal postures. X-linked recessive dystonia parkinsonism (XDP; DYT3; Lubag) is an adult-onset disorder that manifests severe and progressive dystonia with a high frequency of generalization. In search for the anatomical basis for dystonia, we performed postmortem analyses of the functional anatomy of the basal ganglia based on the striatal compartments (ie, the striosomes and the matrix compartment) in XDP. Here, we provide anatomopathological evidence that, in the XDP neostriatum, the matrix compartment is relatively spared in a unique fashion, whereas the striosomes are severely depleted. We also document that there is a differential loss of striatal neuron subclasses in XDP. In view of the three-pathway basal ganglia model, we postulate that the disproportionate involvement of neostriatal compartments and their efferent projections may underlie the manifestation of dystonia in patients with XDP. This study is the first to our knowledge to show specific basal ganglia pathology that could explain the genesis of dystonia in human heredodegenerative movement disorders, suggesting that dystonia may result from an imbalance in the activity between the striosomal and matrix-based pathways.     

Cell density modulates the metastatic aggressiveness of a mouse colon cancer cell line, colon 26

OBJECTIVE: Although cell density in cultured cells has demonstrated several alterations in the nature of cell kinetics, the changes in the metastatic aggressiveness of cancer lines under different cell densities have not yet been studied. METHODS: In the current study, we investigated the influence of changing the cell density of cultured cancer cells (colon 26 and B16-F10) injected into the tail vein in BALB/c mice on the metastatic activity by evaluating the number of lung metastases, and the possible mechanisms of this phenomenon were discussed based on the basis of the results of an invasion assay and a cell adhesion assay. RESULTS: The number of metastatic nodules was significantly higher in the high-density group than in the low one in colon 26 (p < 0.005), however, this phenomenon was not seen in B16-F10. Next, we performed the same experiment by changing the environment to the opposite conditions for the cells in the low- and high-density groups, and the results showed the metastatic activities to be always higher in the high-density group. Moreover, although no difference was seen regarding the invasive activity between the high- and low-density groups, an adhesion assay showed the difference in the adhesion cell rate to be significantly higher in the high-density group especially in early period after coculture with human umbilical vein endothelial cells (HUVEC) (p < 0.05). CONCLUSION: In some cell types, the metastatic activity could be altered and reversed by changing the environment, such as the cell density, during a relatively short period. As a result, the epigenetic changes of cancer cells are thus suggested to play a certain role in the malignant potentiality.     

Laparoscopic transgastric tumor-everting resection of the gastric submucosal tumor located near the esophagogastric junction

Local resection of the stomach is suitable for the treatment of submucosal tumors (SMT). However, it cannot be easily performed laparoscopically on tumors located near the esophagogastric junction. We have developed a new technique, which is called transgastric tumor-everting resection. To identify the location of the SMT laparoscopically without an oral endoscope, an Indiana ink mark was made prior to the operation. The SMT was everted from the gastrotomy and held by the Mini Loop Retractor II. The gastric mucosa could be observed from gastrotomy, allowing us to confirm that the staple line would not cause deformity of the esophagogastric junction. The lesion was then resected, and the gastrotomy was closed simultaneously using the Endo-GIA Universal. This technique is easy, safe, and useful for the laparoscopic resection of gastric SMTs located on the greater curvature or anterior wall of the fornix, near the esophagogastric junction.     

Fine structure of neuronal and glial processes in neuropathology

The cells of the nervous system are characterized by their well‐formed cell processes and by cell‐to‐cell relationships that they form. The neuron reveals essentially cylindrical processes, which form synaptic junctions. On the other hand, the peripheral parts of the glial cells are mainly sheet‐like in nature. Thus, the oligodendroglial cell elaborates many sheet‐like processes, each of which forms a segment of the myelin sheath. Unique cell junction, transverse bands are present at the interface of oligodendroglial processes and the axon. Finally, the astrocytes also form elaborate sheet‐like processes, which separate most of the CNS from the mesodermal tissue as well as surrounding certain neuronal surfaces, including synapses. Punctate adhesions, gap junctions and other adhesive devices are present between astrocytic processes. Defects or anomalies in the neuronal and glial cell processes characterize numerous pathological conditions.