Spike Code Flow in Cultured Neuronal Networks

We observed spike trains produced by one-shot electrical stimulation with 8 × 8 multielectrodes in cultured neuronal networks. Each electrode accepted spikes from several neurons. We extracted the short codes from spike trains and obtained a code spectrum with a nominal time accuracy of 1%. We then constructed code flow maps as movies of the electrode array to observe the code flow of “1101” and “1011,” which are typical pseudorandom sequence such as that we often encountered in a literature and our experiments. They seemed to flow from one electrode to the neighboring one and maintained their shape to some extent. To quantify the flow, we calculated the “maximum cross-correlations” among neighboring electrodes, to find the direction of maximum flow of the codes with lengths less than 8. Normalized maximum cross-correlations were almost constant irrespective of code. Furthermore, if the spike trains were shuffled in interval orders or in electrodes, they became significantly small. Thus, the analysis suggested that local codes of approximately constant shape propagated and conveyed information across the network. Hence, the codes can serve as visible and trackable marks of propagating spike waves as well as evaluating information flow in the neuronal network

Relationship between period of survival and clinicopathological characteristics in patients with colorectal liver metastasis

AIM: Cancer death in the early period after hepatectomy still occurs in patients with colorectal liver metastasis (CLM). We examined the relationship between clinicopathological parameters and survival periods in 130 CLM patients who underwent hepatectomy. PATIENTS/METHODS: Patients were divided into four groups: Group 1 (5-year survivors without tumor relapse), Group 2 (survivors at 2-5years), Group 3 (cancer death at 2-5years), and Group 4 (cancer death within 2years). RESULTS: A short surgical margin was frequent in Group 4 compared to Group 1 (31 vs. 78%, P<0.05). Primary node-positive status, absence of fibrous pseudo-capsular formation, higher Clinical Risk Score, and tumor recurrence within 12months were frequent in Group 4 (P<0.05). Multivariate analysis revealed a short surgical margin (HR; 3.5) and early tumor relapse (HR; 5.9) as independently significant related parameters (P<0.05). CONCLUSIONS: Sufficient surgical margins and careful follow-up for early tumor relapse may be important for improving postoperative outcomes for CLM patients

Comparison of Postoperative Morbidity in Elderly Patients who Underwent Pancreatic Resection

Background/Aims: Operative indications for pancreatectomy in elderly patients with pancreatic disease remain controversial. We examined clinicopathological characteristics and early outcomes in each generation of 147 patients who underwent pancreatectomy. Methodology: Patients were divided into four groups: Group 1 (n=15, 10%), young patients <50 years old; Group 2 (n=65; 44%), patients at 50-69 years old; Group 3 (n=61, 42%), patients at 70-79 years old and Group 4 (n=6, 4%), elderly patients <80 years old. Clinicopathological and surgical parameters were examined, including estimation of physiological ability and surgical stress consisting of preoperative risk score (PRS), surgical stress score (SSS) and comprehensive risk score (CRS). Results: Prevalence of comorbidity and American Society of Anesthesiologists (ASA) score increased significantly with increasing patient age (p<0.05). Extent of pancreatectomy and lymphadenectomy did not differ between groups and surgical records were similar. Tumor stage, post-operative course and complications were similar between groups. PRS and CRS increased significantly with increasing patient age (p<0.05) but SSS did not. Univariate analysis identified presence of systemic comorbidity, ASA score =2 and PRS =0.32 as factors associated with postoperative complications, but no independent predictive parameters were identified on multivariate analysis. Conclusions: Careful management and adequate decisions regarding pancreatectomy upon identification of comorbidity, ASA score and PRS are important in elderly patients with pancreatic disease before pancreatectomy

Evaluation of Surgical Resection for Ampullar Carcinoma at Japanese Single Cancer Institute

Surgical resection is the only radical treatment option for duodenal ampullar carcinoma (AC) that results in an improved patient prognosis. Method: We examined the demographics, surgical records, and outcome in 23 patients with AC undergoing pancreaticoduodenectomy (PD). Results: Of 23 patients, 17 underwent pylorus preserving PD (PPPD) and 6 underwent PD, including subtotal stomach-preserving PD in 5. D2 lymphadenectomy was performed in 17 patients and D3 lymphadenectomy was performed in 6. The combined resection of the superior mesenteric vein was performed in 1 patient. Postoperative cancer recurrence was observed in 32%, and 6 patients died of cancer. The 3-year tumor-free survival rates were not different between the final stages (p=0.64) and the 5-year cancer-related overall survival rates were not different between stages either (p=0.28). Tumor size?3cm resulted in significantly poorer survival rate compared to smaller tumors (p=0.032). Node metastasis at Group 2, and moderately or poorly differentiated adenocarcinoma were significantly associated with poor survival (p<0.05); however, cancer infiltration at cut-end margin, degree of node dissection and curability were not associated with overall prognosis. Conclusions: Radical surgical resection showed good patient prognosis; however, new adjuvant chemotherapy is a promising modality to improve patient survival in AC patients with poor prognostic factors

High Serum Vaspin Concentrations in Patients with Ulcerative Colitis

Background: Adipocytokines are associated with energy homeostasis and mediate various immune responses and inflammatory processes. Vaspin is a novel adipocytokine that is thought to exhibit anti-inflammatory effects. Aim: We aimed to evaluate serum vaspin levels in inflammatory bowel disease (IBD) and determine its possible associations with the course and to clarify its intestinal localization. Methods: Serum samples were obtained from patients with Crohn\u27s disease (CD; n = 30) and ulcerative colitis (UC; n = 33) and from healthy volunteers (controls; n = 26). Enzyme-linked immunosorbent assays were performed for all patients. Vaspin immunohistochemical staining was performed for intestines affected with IBD. Results: Serum vaspin concentrations were significantly higher in patients with UC than in patients with CD and controls (422.9 ± 361.9 vs. 163.4 ± 116.2 vs. 147.5 ± 89.4 pg/mL, respectively; P < 0.01). There was no difference in the serum vaspin concentrations between the patients with CD and controls. There was also no difference in the serum vaspin concentrations between the patients with active IBD and those with inactive IBD. However, the serum vaspin concentrations of most patients with UC increased after remission induction. Vaspin was expressed in the adipocytes of the mesenteric adipose tissues but not in the epithelial or inflammatory cells of large intestines of the patients with IBD. Conclusions: Serum vaspin concentrations are elevated in patients with UC and increase further after remission induction, suggesting that vaspin may aid the auxiliary diagnosis of UC and may be useful for assessing disease activity in patients

キョウショウテン レーザー スキャニング ケンビキョウ ニヨル モウマク シンケイセツ サイボウ ノ サンジゲン ケイタイ ノ カイセキ

複雑な突起形状を有する中枢神経細胞の三次元構造を研究する方法は従来限られており、またそれらの方法によっても非常に時間と手間がかかる上に精度があげられないという問題点があった。しかし、最近になって実用化し普及しつつある共焦点レーザースキャニング顕微鏡(CLSM)はこの問題を解決する可能性を持っている。本研究は、中枢神経系の中でも特に小さく、かつ樹状突起が幅の狭い層に密に展開している網膜神経節細胞の立体構造がCLSM観察によりどの程度解析可能かを検討したものである。Lucifer yellow CH 細胞内注入により網膜神経節細胞を可視化した網膜全伸展標本をCLSMで観察した。その結果、単一細胞の個々の樹状突起や軸索突起を高解像度の投射画像として観察することができた。さらに、細胞の光学的切片像から垂直面への投射像を構成することにより、個々の注入細胞についてその樹状突起の内網状層における展開面を同定し、outer ramifying cell とinner ramifying cellとに明瞭に分類することに成功した。A confocal laser scanning microscope (CLSM)has a great advantage for analyzing three-dimensional structure of neuronal cells, which has been difficult and time-consuming with a conventional microscope. We report here that the innovative microscope can provide us new insights for morphological features of mammalian retinal ganglion cells(RGCs)which were injected intracellularly with a fluorescent dye Lucifer yellow. By means of CLSM, both dendritic and axonal processes located in different focal planes can be observed at a single image without any blur. Without sectioning flat mounted retinas vertically, CLSM enabled us to identify either on-type cells or off-type cells clearly and easily onthe basis of their reconstructed vertical image

シカク ショウガイシャ ユウドウヨウ テンジ タイル ノ ゲンジョウ ト カダイ

視覚障害者(全盲、弱視)が単独で移動する際、移動する経路や環境についての手がかりを事前に持っていなければならない。視覚無しの歩行の場合、移動経路内の随所で、環境と自己の位置関係を確認してゆく必要があり、あらかじめ使えそうな各種の手がかり(触覚的、聴覚的、嗅覚的なもの)を頼りにそれを実行する。この作業は時間を要するうえに、多大な精神的ストレスが生じるため、それを軽減する目的で様々な支援機器、設備が開発されてきた。その中で、視覚障害者誘導用点字タイルは、足底、あるいは杖によって、背景路(床)面から触覚的に検知してたどるもので、現在国内で広く用いられる代表的な支援設備である。しかし、現在、多様な種類のタイルや敷設方法があるため、視覚障害利用者の利便と安全を確保できる統一基準を設けることが期待されている。本論では視覚障害者誘導用タイルの現状とその評価方法などについて述べる。When vision impaired people walk alone, they need to recall various environmental cues from beforehand. The cues include auditory, haptic, olfactory, and visual information obtained from the environment. Without them, they are unable to negotiate with their environment to establish orientation in certain locations. It is not always easy to maintain those clues and to confirm them at the locations over the distance they would travel. Thus, a travel by visually impaired becomes stressful. To lessen this stress, various mobility aids have been developed. 0ne of the representative examples are tactile tiles paved on ground or floor. They appear to be effective from the experience of its use for over twenty years in Japan. We think however that the tactile guiding system can be improved to a better form to enhance safety and convenience of vision impaired to travel alone. In this paper, we discuss mainly about the necessity of tactile guiding systems for the vision impaired and evaluation methods for tactile tiles