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Long-term depression (LTD) at parallel fiber-Purkinje cell (PF-PC) synapses is thought to underlie memory formation in cerebellar motor learning. Recent experimental results, however, suggest that multiple plasticity mechanisms in the cerebellar cortex and cerebellar/vestibular nuclei participate in memory formation. To examine this possibility, we formulated a simple model of the cerebellum with a minimal number of components based on its known anatomy and physiology, implementing both LTD and long-term potentiation (LTP) at PF-PC synapses and mossy fiber-vestibular nuclear neuron (MF-VN) synapses. With this model, we conducted a simulation study of the gain adaptation of optokinetic response (OKR) eye movement. Our model reproduced several important aspects of previously reported experimental results in wild-type and cerebellum-related gene-manipulated mice. First, each 1-h training led to the formation of short-term memory of learned OKR gain at PF-PC synapses, which diminished throughout the day. Second, daily repetition of the training gradually formed long-term memory that was maintained for days at MF-VN synapses. We reproduced such memory formation under various learning conditions. Third, long-term memory formation occurred after training but not during training, indicating that the memory consolidation occurred during posttraining periods. Fourth, spaced training outperformed massed training in long-term memory formation. Finally, we reproduced OKR gain changes consistent with the changes in the vestibuloocular reflex (VOR) previously reported in some gene-manipulated mice.

We investigated somatically perceived inclination of a floor on which an observer was. In the first three experiments, using blindfolded observers, we determined the point of subjective equality (PSE) and the difference limen (DL) for horizontal floor. Orientation of the lying body relative to the axis around which the floor was rotated, distance of the lying body from the rotation axis, posture (standing, sitting, and lying), and age were varied. In the fourth experiment, effects of seeing the floor were examined. The mean PSEs were accurate within ±0.25° in all experiments. The mean DLs varied with condition: 1) The largest DLs were obtained for the blindfolded observers lying orthogonally or obliquely to the rotation axis, 2) the second largest DLs for the blindfolded observers lying parallel to the rotation axis, 3) medium DLs for the blindfolded observers sitting or standing, and 4) the smallest DLs for the standing observers with visual exposure to surroundings. In the last experiment, we determined a scale for inclination from verbally estimating apparent inclination with or without a blindfold. We concluded that the ratio of shear force to normal force was used for estimation of inclination. We discussed synergy of somatic inputs and visual inputs.

While the cerebellum's role in motor function is well recognized, the nature of its concurrent role in cognitive function remains considerably less clear. The current consensus paper gathers diverse views on a variety of important roles played by the cerebellum across a range of cognitive and emotional functions. This paper considers the cerebellum in relation to neurocognitive development, language function, working memory, executive function, and the development of cerebellar internal control models and reflects upon some of the ways in which better understanding the cerebellum's status as a "supervised learning machine" can enrich our ability to understand human function and adaptation. As all contributors agree that the cerebellum plays a role in cognition, there is also an agreement that this conclusion remains highly inferential. Many conclusions about the role of the cerebellum in cognition originate from applying known information about cerebellar contributions to the coordination and quality of movement. These inferences are based on the uniformity of the cerebellum's compositional infrastructure and its apparent modular organization. There is considerable support for this view, based upon observations of patients with pathology within the cerebellum.

Timing control and gain control are twins in motor control. Deficits in precise timing control could cause various motor disturbances. The cerebellum is responsible for timing control within the range of tens to hundreds of milliseconds in both motor and cognitive domains. This implies that the cerebellum has a certain mechanism to represent the passage of time internally. This article reviews the neural mechanisms of timing control in the cerebellum.

For multi-scale and multi-modal neural modeling, it is needed to handle multiple neural models described at different levels seamlessly. Database technology will become more important for these studies, specifically for downloading and handling the neural models seamlessly and effortlessly. To date, conventional neuroinformatics databases have solely been designed to archive model files, but the databases should provide a chance for users to validate the models before downloading them. In this paper, we report our on-going project to develop a cloud-based web service for online simulation called ''Simulation Platform''. Simulation Platform is a cloud of virtual machines running GNU/Linux. On a virtual machine, various software including developer tools such as compilers and libraries, popular neural simulators such as GENESIS, NEURON and NEST, and scientific software such as Gnuplot, R and Octave, are pre-installed. When a user posts a request, a virtual machine is assigned to the user, and the simulation starts on that machine. The user remotely accesses to the machine through a web browser and carries out the simulation, without the need to install any software but a web browser on the user's own computer. Therefore, Simulation Platform is expected to eliminate impediments to handle multiple neural models that require multiple software.

Twenty participants observed and interpreted 16 nail-hammering movies, each of which was composed of motion of four point-lights that were attached to an actor's hand, elbow, and shoulder and the hammer head. Each participant judged the length and the weight of hammers, the sizes of the nails, and the degree of hammering skill, and rated the actor's motion in terms of briskness, lightness, regularity, smoothness, quickness, stability, complexity, and politeness. The results showed the following perceptual characteristics. A higher angular velocity of the hammer at the hand contributed to the perception of the hammering action as more skillful and brisk, whereas an increase in linear velocity of the point at the shoulder was judged as less skilled. The judgment of nail size was positively correlated with the linear velocity of the points at the hand. The judgment of hammer weight was negatively correlated with the linear velocity of the points at the hammer. The different roles that linear and angular velocities of light points play in biological motion perception were discussed.

A long-standing question in neuroscience is how the brain controls movement that requires precisely timed muscle activations. Studies using Pavlovian delay eyeblink conditioning provide good insight into this question. In delay eyeblink conditioning, which is believed to involve the cerebellum, a subject learns an interstimulus interval (ISI) between the onsets of a conditioned stimulus (CS) such as a tone and an unconditioned stimulus such as an airpuff to the eye. After a conditioning phase, the subject’s eyes automatically close or blink when the ISI time has passed after CS onset. This timing information is thought to be represented in some way in the cerebellum. Several computational models of the cerebellum have been proposed to explain the mechanisms of time representation, and they commonly point to the granular layer network. This article will review these computational models and discuss the possible computational power of the cerebellum.

Purpose Hounsfield CT values across coronary CT angiograms constitute CT value-spatial profile curves. These CT profile curves are independent of window settings, and therefore, parameters derived from the curves can be used for objective anatomic analyses. Applicability of parameters derived from the curves to quantification of coronary in-stent patency has not yet been evaluated. Methods Twenty-five CT value-spatial profile curves were delineated from 10 consecutive coronary stents to test correlation between the curve derived parameter (i.e., the minimum extreme value normalized by dividing by the maximum value of the curves obtained at neighboring outside of stents) and three intravascular ultrasound (IVUS) parameters. Results Correlation coefficients between normalized minimum extreme value of CT value-spatial profile curves and three IVUS parameters (such as patent cross-sectional in-stent area, the percentage of patent cross-sectional in-stent area, and coronary artery intra-stent diameter) were 0.65 ( p p p Conclusions CT parameters defined on Hounsfield CT value-spatial profile curves correlated significantly with IVUS parameters for quantitative coronary in-stent patency. A new approach with CT coronary angiography is therefore indicated for the noninvasive assessment of in-stent re-stenosis.

生体内吸収性ポリ-L-乳酸（PLLA）メッシュと骨髄海綿骨細片（PCBM）を用いて，Tissue Engineeringを応用した下顎骨再建法を施行し，長期経過観察を行った症例について検討した。対象は術後6ヶ月の評価で，著効，有効の40例（悪性腫瘍；14例，良性腫瘍；26例）である。下顎骨切除法は辺縁切除；21例，区域切除；16例，半側切除；3例，観察期間は1年～12年（平均6年2ヶ月）であった。メッシュトレーに起因する有害事象は認められなかった。再生骨の吸収は10%未満；32例（80%），10～20%；6例，20～30%；2例で，1年以後の骨吸収は少なく，早期に咬合回復したものは骨化が進む傾向があった。通常義歯装用は21例，さらに歯科インプラント植立は5例であった。本法は下顎骨の良好な形態と機能回復を計ることが可能で，手術侵襲が少ない。義歯装着や歯科インプラントによる咬合や咀嚼機能の改善が期待できる。

In Pavlovian delay eyeblink conditioning, the cerebellum represents the passage-of-time (POT) between onsets of conditioned and unconditioned stimuli (CS and US, respectively). To study possible computational mechanisms of the POT representation we built a large-scale spiking network model of the cerebellum. Consistent with our previous rate-coding model, we found two conditions necessary for the present model to represent the POT with a dynamic population of active granule cells: (i) long temporal integration of input signals; and (ii) random recurrent connections between granule and Golgi cells. When these conditions were satisfied, a nonrecurrent sequence of active granule cell populations was generated in response to a CS and, conversely, the POT from the CS onset was able to be read out from the sequence. Specifically, simulated N-methyl-D-aspartate (NMDA) channels with a long decay time constant at granule and Golgi cells were responsible for the long temporal integration. Thus, blocking the NMDA channels or ablating Golgi cells impaired the POT representation. Simulated glomerulus structure made POT representation robust against noise in mossy fibre inputs. Long-term potentiation induced at mossy fibre synapses on granule cells also served to enhance the robustness. We reproduced some experimental results of Pavlovian delay eyeblink conditioning using the present model. These results suggest that the recurrent network in the granular layer and NMDA channels in granule and Golgi cells play an essential role in the timing mechanisms in the cerebellum, whereas the glomerulus serves to realize a robust representation of time.

Despite male predominance in the prevalence of hypertrophic cardiomyopathy (HCM), repeated diagnosis at our institute indicates a possible higher prevalence of deep Q waves with HCM in women.The current study examined gender similarities and differences in the prevalence of deep Q waves in HCM and in the morphologic and electrocardiographic features of HCM with deep Q waves.Patients with HCM underwent cardiac magnetic resonance (CMR) imaging to identify the prevalence of deep Q waves in electrocardiographic limb leads, and to analyze the relationship between distribution patterns of deep Q waves and those of the localization of maximum amplitude of left ventricular (LV) hypertrophy. Contiguous LV short-axis images were obtained from the base toward the apex.Of the 200 consecutive patients (172 males, aged 20-78 years; 28 females, aged 16-79 years) with HCM who underwent CMR imaging, 10 male and 8 female patients had deep Q waves. Deep Q waves were more prevalent in females with HCM than in their male counterparts (28.6% vs 5.8%, respectively; P0.001). Of the 18 patients with deep Q waves, maximum wall thickness was localized at either the basal anterior wall or the midventricular septum in 9 (90%) of the 10 male patients and 6 (75%) of the 8 female patients. In both sexes, the Q wave distribution pattern of I and aVL and of II and aVF indicated localization of maximum hypertrophy at the midventricular septum in 6 (75%) of the 8 patients with the former pattern, and at the basal anterior wall in 9 (90%) of the 10 patients with the latter pattern.Diagnostic deep Q waves were detected more frequently in female patients with HCM than in their male counterparts. In HCM with deep Q waves in limb leads, morphologic and electrocardiographic analysis showed similar features in both sexes.

To examine the effect of experience on the developmental plasticity of functional maps in the visual cortex, we need to establish a method for a stable visual experience manipulation under the freely moving condition. For this purpose, we fabricated goggles that are chronically mounted stably on the animal's head, but easy to replace according to the animal's growth. Here we report the design of the goggles and the method of mounting them on the head of animals. By this method, combined with the intrinsic signal optical imaging technique, we were able to observe a rapid and robust reorganization of orientation maps.

Purpose Coronary artery vascular edge recognition on computed tomography (CT) angiograms is influenced by window parameters. A noninvasive method for vascular edge recognition independent of window setting with use of multi-detector row CT was contrived and its feasibility and accuracy were estimated by intravascular ultrasound (IVUS). Methods Multi-detector row CT was performed to obtain 29 CT spatial profile curves by setting a line cursor across short-axis coronary angiograms processed by multi-planar reconstruction. IVUS was also performed to determine the reference coronary diameter. IVUS diameter was fitted horizontally between two points on the upward and downward slopes of the profile curves and Hounsfield number was measured at the fitted level to test seven candidate indexes for definition of intravascular coronary diameter. The best index from the curves should show the best agreement with IVUS diameter. Results Of the seven candidates the agreement was the best (agreement: 16±11%) when the two ratios of Hounsfield number at the level of IVUS diameter over that at the peak on the profile curves were used with water and with fat as the background tissue. These edge definitions were achieved by cutting the horizontal distance by the curves at the level defined by the ratio of 0.41 for water background and 0.57 for fat background. Conclusions Vascular edge recognition of the coronary artery with CT spatial profile curves was feasible and the contrived method could define the coronary diameter with reasonable agreement.

The need for long-term follow-up in Kawasaki disease is poorly recognized although cardiac sudden death attacks asymptomatic young people with past illness after a long latent period. Therefore, in order to prevent cardiac disasters, high risk groups should be identified and the prevalence rate of the disease should be determined for crisis management. A total of 9,965 consecutive freshmen at the University of Tokyo were the subject of a questionnaire. Their parents/guardians who were briefed on the diagnostic criteria of the acute phase of Kawasaki disease actually completed the questionnaire. Students with a positive diagnosis underwent rest and exercise-stress electrocardiography and routine echocardiography. The overall prevalence rate was 0.57%. The rate in males (0.63%) was greater than that in females (0.32%) (P < 0.05). Electrocardiography and routine echocardiography identified no indices specific to a past illness of Kawasaki disease. The prevalence rate indicated that about 6 in 1000 students were high risk students who needed special care while at university. Since there are few symptoms and no signs indicating a past illness of Kawasaki disease, intensive history-taking from parents/guardians who are familiar with their acute symptoms during childhood is required in order to identify those at high risk of a coronary event.

A randomized and prospective study was designed to prove the efficacy of angiotensin II receptor blockers (ARB) in the amelioration of myocardial impairment in hypertrophic nonobstructive cardiomyopathy (HNCM). Nineteen consecutive patients with HNCM were randomly assigned to two groups and then underwent cine magnetic resonance evaluation of left ventricular mass (LVM) twice just before and after one year of observation. In the ARB group, 50 mg of losartan potassium was administered once daily during the observation period. The ratio of LVM after the observation period over that before the period was blindly compared between the two groups to estimate morphologically the ameliorative effect of ARB. In the ARB group, LVM was 203 +/- 47 cm(3) before the treatment period and 190 +/- 55 cm(3) after the period and the ratio of the final LVM over the initial LVM was 0.93 +/- 0.10. In the non-ARB group the initial and final LVM values were 177 +/- 48 cm(3) and 179 +/- 45 cm(3), and the ratio of the final LVM over the initial LVM was 1.02 +/- 0.07. The ratio of the final LVM over the initial LVM in the ARB group was significantly smaller (P = 0.03) than that in the non-ARB group. The smaller ratio in the ARB group strongly indicates that ARB ameliorated the natural course of HNCM during the one year observation period. Thus, this is the first demonstration of the therapeutic efficacy of ARB in human HNCM.

This cross-sectional study aimed to determine the utility of ultrasonography with improved resolution using a high-frequency probe for dialysis-related carpal tunnel syndrome (CTS). This study targeted 125 hemodialysis patients at our hospital. A 12 MHz probe was placed on the carpal tunnel area to identify the median nerve. The compression rate of the nerve was calculated by measuring the smallest diameter of the compressed nerve and largest diameter of the unaffected part. To quantify CTS symptoms, we determined the presence of Tinel's sign, measured pinch strength, and used questionnaires to assess numbness and pain. The association of these clinical data with the compression rate was examined. Mean compression rate was 12.1 ± 1.1%. The compression rate cutoff value for those positive with Tinel's sign was 25%, (sensitivity and specificity were 0.80 and 0.91, respectively), and that for those with a history of CTS surgery was 25% (sensitivity and specificity were 0.67 and 0.89, respectively). Multiple regression analysis identified duration of dialysis, β2-microglobulin(β2-Mg) concentration, positivity for Tinel's sign, history of CTS surgery, and pinch strength as independent compression rate determinants. Notably, compression rates were significantly higher in patients with a ≥4-year duration of dialysis and a β2-Mg level of 20 mg/L or more. The compression rate of the median nerve measured by an improved ultrasound device significantly correlated with clinical symptoms, medical history, and serological features associated with dialysis-related CTS. Because ultrasonography is non-invasive, the examination might be a simple method especially for early diagnosis of dialysis-related CTS.

生体内吸収性のポリ-L-乳酸（PLLA）メッシュと骨髄海綿骨細片（PCBM）用いた下顎骨再生法を中心にして，下顎骨の再構築法について述べた。腫瘍57例（悪性腫瘍23例，良性腫瘍34例）の6か月後の臨床評価では，著効が30例（52.6%），有効が17例（29.8%），無効が10例（17.5%）であった。1-11（平均5.3年）年の長期観察では，39例中，31例（79.5%）が10%未満の吸収に留まった。メッシュに起因する有害事象はみられなかった。再生骨への義歯装用は21例，歯科インプラント施行例は4例であった。本法は従来の骨移植法に比べて，手術侵襲が少なく，形態と機能回復に優れている。今後，局所の血行不良例，高齢者や8cmを越えるような広範囲の区域切除例に対しては，血行の確保とともに，骨形成を促進して，効率よく骨再生を導くための生理活性因子あるいは培養骨の応用が期待される。

We studied the dynamics of a neural network that has both recurrent excitatory and random inhibitory connections. Neurons started to become active when a relatively weak transient excitatory signal was presented and the activity was sustained due to the recurrent excitatory connections. The sustained activity stopped when a strong transient signal was presented or when neurons were disinhibited. The random inhibitory connections modulated the activity patterns of neurons so that the patterns evolved without recurrence with time. Hence, a time passage between the onsets of the two transient signals was represented by the sequence of activity patterns. We then applied this model to represent the trace eyeblink conditioning, which is mediated by the hippocampus. We assumed this model as CA3 of the hippocampus and considered an output neuron corresponding to a neuron in CA1. The activity pattern of the output neuron was similar to that of CA1 neurons during trace eyeblink conditioning, which was experimentally observed.

生体内吸収性のポリ-L-乳酸（PLLA）メッシュと骨髄海綿骨細片（PCBM）による下顎骨再生法を述べた。対象は悪性腫瘍22例，良性腫瘍30例，嚢胞5例，骨髄炎2例の計59例である。手術法はPLLAメッシュのシートまたはトレーを欠損部に合わせて裁断し，加温，成形し，既存骨にstainless wireで固定後，腸骨から採取したPCBMをトレー内に充填した。6か月後の臨床評価では，著効が32例（54.2%），有効が17例（28.8%），無効が10例（16.9%）であった。再生骨の長期観察（40例，1～10年，平均5.0年）では，31例（77.5%）が10%未満の吸収に止まり，早期に補綴処置などにより機能回復された例は骨吸収が少ない傾向であった。メッシュに起因する有害事象はみられなかった。本法は手術侵襲が少なく，義歯装用，インプラントを可能とするなど，下顎骨再生法として有用と考えられた。

Nowadays, evidence-based medicine has entered the mainstream of clinical judgement and the human genome has been completely decoded. Even the concept of individually designed medicine, that is, tailor-made medicine, is now being discussed. Due to their complexity, however, management methods for clinical information have yet to be established. We have conducted a study on a universal technique which enables one to select or produce by employing information processing technology clinical findings from various clinical information generated in vast quantity in day-to-day clinical practice, and to share such information and/or the results of analysis between two or more institutions. In this study, clinically useful findings have been successfully obtained by systematizing actual clinical information and genomic information obtained by an appropriate collecting and management method of information with due consideration to ethical issues. We report here these medical achievements as well as technological ones which will play a role in propagating such medical achievements.

The solution polycondensation of a mixture of various parts of isophthalic acid (IPA) and terephthalic acid (TPA) with 4,4′-dihydroxydiphenylsulfone (BPS) with tosyl chloride/dimethylformamide/pyridine as a condensing agent was studied. To elucidate how the reaction should be done to obtain copolymers of high molecular weights, we examined the two-stage copolycondensation with BPS and 2,2-bis(4-hydroxyphenyl)propanes (BPAs) by changing the content of IPA/TPA and the amount of BPS or BPA used in the initial reaction. Controlling the reaction at an earlier stage could facilitate the copolycondensation. The polyesters of IPA/TPA and BPS of moderate inherent viscosity values up to 1.0 were obtained by the two-stage reaction with optimal amounts of BPS first and then additional BPS. Satisfactory results were also obtained by the dropwise addition of BPS over 10–20 min in the preparation of the IPA/TPA–BPS polymers containing less than 50 mol % TPA. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2607–2610, 2002

Purpose Exposure time within 40 ms for chest radiography is brief, and therefore cardiac timing of exposure may influence cardio-thoracic ratio (CTR). To determine whether or not ECG triggering is required, it is necessary to evaluate the cardiac size during the complete cardiac cycle. Methods A cine magnetic resonance series was obtained in eight contiguous coronal planes in ten patients. At a single cardiac phase, the maximum horizontal length from the middle to the right cardiac border was measured on each coronal image. The transverse diameter to the right border of the cardiac silhouette projected on the imaginary radiograph was defined as the greatest value of length obtained by magnifying the eight maximum horizontal lengths in inverse projection to the distance from the imaginary X-ray source to each imaging plane. The transverse diameter to the left border was also defined. The two diameters were then summed to describe the cardiac size at the common cardiac phase. To constitute cardiac phase-cardiac size curves this procedure was repeated for eight cardiac phases. Results On cardiac phase-cardiac size curves, the maximum transverse silhouette of the heart (diameter: 155±15 mm) was obtained at a delay time of 0 ms from R wave and the minimum size (diameter: 149±16 mm) was identified at a delay time of 240 ms in all patients. Conclusions Although the fluctuation of the size of the projected cardiac silhouette during a cardiac cycle was statistically significant, the fluctuation magnitude of 2% indicated clinical acceptability of chest radiography without electrocardiographic gating.

Sensorimotor control and learning require the function of sophisticated neural system. Cerebellum is one such brain region which comprises more than half of the total neuron population in the entire brain. Capable of simulating a bio-realistic cerebellum model provides important information for neuroscience and engineering. Here we present a Network-on-Chip (NoC) hardware architecture for implementing a bio-realistic cerebellum model of passage-of-time (POT) encoding with 100,000 neurons. The results demonstrate that our implementation can reproduce the POT functionality properly. The maximum computational speed can reach 25.6 ms for simulating 1 sec real world activities. Our silicon cerebellum can be readily interface with in vivo or in vitro experiment and be adapted as a potential neuroprosthetic platform for future biological or clinical applications.

The cerebellum plays a critical role for sensorimotor control and learning. However dysmertria or delays in movements' onsets consequent to damages in cerebellum cannot be cured completely at the moment. To foster a potential cure based on neuroprosthetic technology, we present a frame-based Network-on-Chip (NoC) hardware architecture for implementing a bio-realistic cerebellum model with 100,000 neurons, which has been used for studying timing control or passage-of-time (POT) encoding mediated by the cerebellum. The results demonstrate that our implementation can reproduce the POT functionality properly. The computational speed can achieve to 25.6 ms for simulating 1 sec real world activities. Furthermore, we show a hardware electronic setup and illustrate how the silicon cerebellum can be adapted as a potential neuroprosthetic platform for future biological or clinical applications.

Long-term depression (LTD) here concerned is persistent attenuation of transmission efficiency from a bundle of parallel fibers to a Purkinje cell. Uniquely, LTD is induced by conjunctive activation of the parallel fibers and the climbing fiber that innervates that Purkinje cell. Cellular and molecular processes underlying LTD occur postsynaptically. In the 1960s, LTD was conceived as a theoretical possibility and in the 1980s, substantiated experimentally. Through further investigations using various pharmacological or genetic manipulations of LTD, a concept was formed that LTD plays a major role in learning capability of the cerebellum (referred to as "Marr-Albus-Ito hypothesis"). In this chapter, following a historical overview, recent intensive investigations of LTD are reviewed. Complex signal transduction and receptor recycling processes underlying LTD are analyzed, and roles of LTD in reflexes and voluntary movements are defined. The significance of LTD is considered from viewpoints of neural network modeling. Finally, the controversy arising from the recent finding in a few studies that whereas LTD is blocked pharmacologically or genetically, motor learning in awake behaving animals remains seemingly unchanged is examined. We conjecture how this mismatch arises, either from a methodological problem or from a network nature, and how it might be resolved.

Long-term depression (LTD) here concerned is persistent attenuation of transmission efficiency from a bundle of parallel fibers to a Purkinje cell. Uniquely, LTD is induced by conjunctive activation of the parallel fibers and the climbing fiber that innervates that Purkinje cell. Cellular and molecular processes underlying LTD occur postsynaptically. In the 1960s, LTD was conceived as a theoretical possibility and in the 1980s, substantiated experimentally. Through further investigations using various pharmacological or genetic manipulations of LTD, a concept was formed that LTD plays a major role in learning capability of the cerebellum (referred to as "Marr-Albus-Ito hypothesis"). In this chapter, following a historical overview, recent intensive investigations of LTD are reviewed. Complex signal transduction and receptor recycling processes underlying LTD are analyzed, and roles of LTD in reflexes and voluntary movements are defined. The significance of LTD is considered from viewpoints of neural network modeling. Finally, the controversy arising from the recent finding in a few studies that whereas LTD is blocked pharmacologically or genetically, motor learning in awake behaving animals remains seemingly unchanged is examined. We conjecture how this mismatch arises, either from a methodological problem or from a network nature, and how it might be resolved.

The aims of this study were to investigate morbidity, mortality, and survival of patients with ductal adenocarcinoma of the pancreas who underwent pancreatectomy without (group 1) or with (group 2) en bloc portal vein resection and to study the degree of carcinoma invasion of the portal vein in group 2. The medical records of 46 and 28 patients in groups 1 and 2, respectively, were reviewed. In addition, the degree of invasion of the wall of the portal vein was categorized histologically into three types: type I, transmural invasion involving the intima; type II, invasion of the wall of the vein without intimal involvement; and type III, compression of the wall of the vein by surrounding carcinoma without true invasion. The morbidity and mortality in group 1 (26% and 4%) were not different from those in group 2 (32% and 4%). Similarly, there was no difference in survival between the two groups. Survival tended to vary directly with the depth of invasion of the wall of the portal vein: type I 6.8 +/- 1.9 months; type II 15.3 +/- 6.4 months; type III 20.6 +/- 13.0 months. These findings suggest that en bloc resection of the pancreas and the portal vein does not increase mortality and morbidity after pancreatectomy; survival after en bloc resection was similar to that of patients not requiring portal vein resection. Combined resection of the pancreas with the portal vein could be an option in the treatment of pancreatic cancer with direct invasion of the portal vein.

口腔癌患者に対し日本の口腔外科医が癌告知をどのように行っているのか, その現状と問題点をさぐる目的で本研究を行った。九州・沖縄, 近畿, 中部地区の口腔外科施設を対象に15項目からなる癌告知に関する質問表を送付した。90施設 (87.4%) より回答を得た。44施設 (48.9%) で癌告知を常時もしくは多く行っていた。27施設 (30%) では家族の了承を得た後に患者に告知を行っていた。73施設 (81.1%) は近い将来癌告知は本邦でも普及すると考えていた。57施設 (63.3%) で口腔癌告知の障害として告知後の精神的サポート体制の不十分を挙げていた。今回の調査では49%が口腔癌告知に積極的姿勢を示していた。1994年の富田の調査では70%が口腔癌告知に否定的であった。口腔外科医の癌告知に対する態度の変化は明かであった。本研究の結果より, 今後更に口腔癌の告知は普及すると思われる。しかし, 癌告知後の患者への精神的サポート体制の確立が'必要である。

Purpose: This study was designed to compare the clinical characteristics of two-dimensional coronary magnetic resonance (MR) angiography with those of three-dimensional MR angiography and to describe the applicability of the two coronary MR angiographies to screening surveys and/or follow-up tests. Methods: Thirty-five patients (female: 9, male: 26) underwent conventional coronary angiography, and either two- or three-dimensional coronary MR angiography was performed with (in an informed series) and without (in a blinded series) knowledge of the results obtained by conventional coronary angiography. Results: Lack of images depicting the coronary lesions resulted in a low sensitivity of 56% with blinded two-dimensional coronary MR angiography. With conventional angiography, the specificity eventually reached 100%. The sensitivity (79%) using three-dimensional coronary MR angiography in the blinded series tended to be higher than that (56%) of blinded two-dimensional angiography ( P =0.13), whereas, in the informed series three-dimensional angiography showed improvement neither in sensitivity ( P =0.32) nor specificity ( P =0.32). Conclusions: The capability of two-dimensional coronary MR angiography for accurate delineation of known lesions may indicate a role in follow-up tests for known lesions. Three-dimensional coronary MR angiography, on the other hand, may look promising for screening surveys; the present sensitivity and specificity are insufficient for clinical application.

症例は52歳の女性. 腹痛を主訴として前医受診, 手術にてIVC原発腫瘍と判明したため当院紹介された. IVC造影ではIVCの閉塞, 側副血行路の形成は見られなかった. 開腹すると腫瘍は中部IVCより壁外性に発育しており, 右腎静脈への浸潤を認めた. 右腎静脈を大伏在静脈にて再建した後, IVCの単純遮断下に腫瘍をIVCとともに切除し, IVCは人工血管にて再建した. 病理組織診断は平滑筋肉腫であった. 術後6か月のMRI検査ではIVCのpatencyは保たれていた. 術後17か月経過した現在, 再発の兆候なく外来通院中である. 下大静脈原発平滑筋肉腫は本邦での報告は自験例を含めて53例で, IVC切除後人工血管にて再建された症例は12例である. IVC切除にあたっては血流遮断時の体外循環の必要性, 腎静脈の処理方法などをIVC造影, 術中所見から判断することが重要である.

耳下腺腫瘤16例, 顎下腺腫瘤3例, 計19例の患者に対してCT-sialogramを行い検討した。19例の患者の年齢は5歳から78歳で平均年齢57.3歳であった。検査は術前に行い手術後の病理組織検査では良性腫瘍13例, 嚢胞1例, 悪性腫瘍4例, 悪性リンパ腫1例であった。CT-sialo.所見では腫瘤検出率は100%であり, 全例でMajor ductが描出され腫瘍と顔面神経の走行との位置関係を知る指針となった。CT-sialo.所見にて直径約10mmの上皮筋上皮癌は全く悪性を疑う像が見られなかった。CT-sialo.にて良性腫瘍と判定した2例に, 手術時周囲組織と癒着が見られた。唾液腺腫瘍の良性悪性の判定には辺縁の形状, 腫瘍内部のlow density areaや点状漏洩像の有無が有用な所見であった。CT-sialo.は腫瘍の位置, 形態など得られる情報が多く, 唾液腺腫瘍の診断に際して早期に行うべき検査方法である。

We describe an 86-year-old woman with a large parotid tumor. Ten years previously, she had first noticed a tumor about the size of the tip of the little finger in the right parotid region.The tumor had become very large. Her Hematological examination showed a pattern of severe anemia and undernourishment. Excision of the tumor was carried out, and the excised tumor measured 200×180×150mm and weighed 900g. Histological examination revealed that the tumor was a carcinoma in pleomorphic adenoma. There has been no evidence of recurrence after 3.5 years of follow up.

Background: Non-invasive assessment of volume and function on the right ventricle (RV) for pulmonary hypertension (PH) is limited. Methods and Results: Patients with PH (n=23) underwent 3-dimensional (D) echocardiography (3DECHO), with cardiac magnetic resonance imaging to confirm its precision, and right heart catheterization. On linear regression analysis the RV end-systolic volume index (ESVI) was positively correlated with pulmonary vascular resistance (PVR) and mean pulmonary arterial pressure (mPAP; R=0.42 and 0.46, P=0.03 and 0.03, respectively). The RV end-diastolic volume index (EDVI) was positively correlated with mPAP (R=0.41, P

Accumulating experimental evidence suggests that the memory trace of ocular reflex adaptation is initially encoded in the cerebellar cortex, and later transferred to the cerebellar nuclei for consolidation through repetitions of training. However, the memory transfer is not well characterized in the learning of voluntary movement. Here, we implement our model of memory transfer to interpret the data of prism adaptation (Martin, Keating, Goodkin, Bastian, & Thach, 1996a, 1996b), assuming that the cerebellar nuclear memory formed by memory transfer is used for normal throwing. When the subject was trained to throw darts wearing prisms in 30-40 trials, the short-term memory for recalibrating the throwing direction by gaze would be formed in the cerebellar cortex, which was extinguished by throwing with normal vision in a similar number of trials. After weeks of repetitions of short-term prism adaptation, the long-term memory would be formed in the cerebellar nuclei through memory transfer, which enabled one to throw darts to the center wearing prisms without any training. These two long-term memories, one for throwing with normal vision and the other for throwing wearing prisms, are assumed to be utilized automatically under volitional control. Moreover, when the prisms were changed to new prisms, a new memory for adapting to the new prisms would be formed in the cerebellar cortex, just to counterbalance the nuclear memory of long-term adaptation to the original prisms in a similar number of trials. These results suggest that memory transfer may occur in the learning of voluntary movements.

The cerebellum has two distinct memory sites. A single session of behavioral training forms short-term memory in the cerebellar cortex, and by repeating the training, long-term memory is formed in the cerebellar or vestibular nuclei, as if the memory is transferred from the cortex to the nuclei. We propose a simple network model of the cerebellum for the formation and transfer of motor memory. We assume a Hebbian rule with a postsynaptic gating mechanism for synaptic plasticity in the nuclei. We carry out computer simulation of gain adaptation of vestibulo-ocular reflex (VOR) and demonstrate robust memory transfer: the synaptic weight in the nuclei does not diverge to infinity. We suggest that memory transfer occurs mainly after training, not during training, and that spontaneous activity of Purkinje cells after training is necessary for memory transfer.

Computational models and theoretical tools are essential components in computational neuroscience. A number of models and tools have been developed and registered at various online databases such as ModelDB and J-Node Platforms. Yet, the reuse of such resources still remains quite difficult. For example, to carry out a computer simulation of a model, we have to download the program from the database, extract, read instructions, compile if the program is written in a general programming language such as C, install the appropriate neural simulator if it is written for a simulator such as GENESIS, NEURON, and NEST, and finally we may be ready to do it, if no problems occurs during all the setup mentioned above. How can we avoid this hustle? As a solution of it, we introduce a cloud-based system for online computer simulation called Simulation Platform. Simulation Platform is a cloud of virtual machines running GNU/Linux. On a virtual machine, various software including developer tools such as compilers and libraries, popular neural simulators, and scientific software such as Gnuplot, R and Octave, are pre-installed. When a user posts a request, a virtual machine is assigned to the user, and the simulation starts on that machine. The user can remotely access the virtual machine through a web browser and carries out the simulation interactively (a screenshot is shown in Fig. ​Fig.1).1). There is no need to install any software. It only requires a web browser. Therefore, Simulation Platform provides an ubiquitous computing environment for computational neuroscience research so as to free neuroscientists from tedious computer administration tasks and allow them to solely concentrate on their science. A demo site is open at http://sf4.sim.neuroinf.jp/~tyam/cns11/. Figure 1 A screenshot of a web browser during a computer simulation.

In order to clarify whether the detection of a point mutation in the c-Ki-ras gene at codon 12 in tumor tissues can assist in predicting the tumor's biological grade of malignancy, two types of tumors were investigated; one was called "carcinoma in the pancreatic head region," and the other was intraductal mucin-hypersecreting neoplasm of the pancreas (IMHN). Dot hybridization and a modified PCR technique developed by Haliassos et al. were employed. Among 16 cases of tumors in the pancreatic head region, the point mutation was detected with a high frequency only in pancreatic ductal cell carcinomas (five out of six cases, 83.3%), but was not detected in extrahepatic bile duct carcinomas (0/5) or in ampullary carcinomas (0/5). In pancreatic ductal cell carcinomas, no relation was found between the occurrence of the point mutation and the histological type of the tumor. Among 20 cases of IMHNs, the point mutation was found in 11 cases (55%). No relation was found between the occurrence of the mutation and the size of IMHNs. However, as the grade of cell atypia increased, the frequency of the mutation tended to become higher. These results suggest that detection of this point mutation might be useful for distinguishing pancreatic ductal cell carcinoma from those of other origins in the pancreatic head region, and for the determination of the histopathological grade of malignancy in IMHNs.

進行癌症例に対しては痛みや治療による精神的・肉体的負担の少ない治療手段によりQOLを維持することが望まれる。われわれは手術不能と考えられた進展癌症例に対して, 上甲状腺動脈あるいは外頸動脈からの体内埋め込み式one-shot動注装置を用いた化学療法を試みた。本システムは皮膚穿刺部からの感染の危険がない, カテーテルの閉塞・抜去・切断がない, 入浴・洗髪・髭剃りが可能で, 審美障害もなく日常生活に制限を加えない利点を有していた。また, 頻回の採血や点滴などの栄養補給, 抗癌剤以外の薬液の注入にも利用でき長期間にわたって安全かつ簡便に反復して使用することができた。

1977年から1990年までの14年間に口腔癌54症例に対して56回の根治手術と種々の皮弁・筋皮弁 (64皮弁) を用いて即時再建を行い, これらの症例の臨床的観察を行った。一次症例は32例 (Stage II: 5例, Stage III: 8例, Stage IV: 19例) , 二次症例は22例であった。原発部位は舌が20例, 下顎歯肉が12例, 口底が10例, 頬粘膜と口峡咽頭が5例, 上顎歯肉と顎下腺が1例であった。病理組織型は扁平上皮癌が51例, 唾液腺癌が2例, 未分化癌が1例であった。切除範囲は原発部位と病期により様々であった。再建に用いた皮弁は大胸筋皮弁が31例, DP皮弁が18例, 広背筋皮弁が7例, 前腕皮弁が5例, 胸鎖乳突筋皮弁が2例であった。平均手術時間は8時間50分, 平均出血量は14939, 皮弁の完全生着率は71.4%であった。5年累積生存率は一次症例が51.7%, 二次症例が24.1%, 全症例では42.5%であった。これらの結果より口腔癌進展例において, 切除手術と即時再建の組み合わせは有効な治療法と思われたが, 今後の課題としては適確な治療方針の選択により二次症例を減少させること, 遠隔転移の防止に有効な化学療法の開発, 重複癌の早期発見, 良好な機能回復のための中咽頭の再建法, 生体材料の開発が重要と考えられた。