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Visual search is a useful experimental paradigm investigating various aspects of attention. For efficient search, participants must avoid revisiting previously viewed objects. Inhibitory tagging and inhibition of return are phenomena related to this process, but their neural mechanisms are yet to be elucidated. Recent studies have shown that the rate of revisit behavior during visual search correlates with working memory capacity. This suggests that top-down signals from the frontal executive system alter the priority map that guides attention and eye movements. With this in mind, we have developed a novel visual search paradigm with many identical distractors and an evaluation model that assesses multiple parameters of working memory. The model incorporated memory capacity, memory decay, and utility rate, and when applied to data obtained from experimental animals, these parameters could be reliably evaluated. Furthermore, using the behavioral paradigm and model, we found that systemic administration of subanesthetic dose of ketamine decreased utility rate and memory capacity, while nicotine administration increased utility rate. Since our behavioral paradigm does not require complex instruction, it can be applied to a variety of patients in future clinical studies.

A 65-year-old woman with a history of chronic hepatitis B was referred to our hospital for the examination of abdominal lymphadenopathy and diffuse lesions in the liver. Endoscopic ultrasound-guided fine-needle aspiration biopsy and liver biopsy were performed, and mucosa-associated lymphoid tissue (MALT) lymphoma was found in both. Based on the results of various images, a diagnosis of primary hepatic MALT lymphoma, Ann Arbor classification stage IV was reached at. Entecavir administration, H. pylori eradication therapy, and chemotherapy were performed, and remission was induced. The tumor condition remained unchanged after H. pylori eradication therapy and Entecavir administration. Subsequently, she became symptomatic, so chemotherapy was performed, leading to remission. We herein report a case of hepatic MALT lymphoma associated with chronic hepatitis B.

A 57-year-old female with a history of Cowden's disease was referred to our hospital because of black stool, loss of consciousness, and severe anemia. Upper and lower gastrointestinal endoscopy findings could not confirm the source of hemorrhage. Capsule endoscopy (CE) of the small intestine showed an active exudative hemorrhagic site near the ileum, although a definitive diagnosis was difficult. In a double balloon enteroscopy examination, it was difficult to observe the entire small intestine due to adhesions and the responsible lesion could not be confirmed, even when ink spots were applied to the deepest observation points through the mouth and anus. Hemostasis spontaneously occurred, and then anemia occurred again approximately 1 month later and a second CE examination was performed including passage of an ink stick through the oral side, which revealed an exudative elevated polyp with erosion and a white moss appearance in the ileum. Partial ileal resection was performed and pyogenic granuloma of the small intestine was the diagnosis. We report here a case of pyogenic granuloma of the small intestine associated with Cowden's disease.

We report a case of granulocyte-colony stimulating factor(G-CSF)producing breast cancer in a 54-year-old woman. Eight months after surgery, multiple liver and pulmonary metastases appeared. They progressed rapidly in 2 weeks and she had a high fever of 38 degrees. Serum G-CSF was high, and positive cells were found by immunostaining of the primary tumor. Chemotherapy was initially successful but she died 4 months after relapse.

When waiting for a traffic light or dancing to a musical beat, we unconsciously keep track of elapsed time and precisely predict the timing of forthcoming sensory events. Temporal monitoring and prediction are integral to our daily life, and are regulated by neuronal processes through multiple global networks involving the frontoparietal cortices, the basal ganglia and the cerebellum. These processes are also known to be influenced by a variety of internal state and neuromodulators. Here, we review recent advance of research in the field.

A 55-year-old woman underwent subtotal stomach-preserving pancreaticoduodenectomy for pancreatic ductal adenocarcinoma( PDAC) in July 2008. The final diagnosis was Stage I PDAC according to the Union for International Cancer Control( UICC) TNM classification. After the operation, adjuvant chemotherapy with gemcitabine was administered for 6 months. The tumor marker level increased at 49 months after the operation, and 18-fluoro-deoxyglucose (FDG)-positron emission tomography( PET) showed FDG accumulation in the remnant pancreas. A hypovascular tumor was revealed in the remnant pancreas on computed tomography( CT). As PDAC was diagnosed without distant metastasis, completion pancreatectomy was performed. Histopathological investigation revealed PDAC with invasion into the muscularis propria of the anastomosed jejunum and splenic plexus. The final diagnosis was T3N0M0 UICC Stage IIA metachronous PDAC. The postoperative course was uneventful. However, multiple liver metastases and local recurrence were detected on CT 2 months after resection, and the patient died 3 months after resection. Most reported cases of metachronous PDACs were diagnosed at an advanced stage despite regular follow-ups after the initial resection. Further investigation is needed to determine the adequate surveillance time and novel therapeutic strategies.

Complete resection of advanced bile duct cancer is difficult due to the anatomical location of the tumor and invasion into other organs. Even if a complete resection is achieved, the survival rates of patients with bile duct cancer after surgery are lower as compared to those associated with other gastrointestinal tumors. Certain cases with para-aortic lymph node metastasis have a poor prognosis. In the present report, we describe a case involving long-term survival following bile duct cancer that was treated by multidisciplinary therapy (particle radiotherapy, surgical resection, chemotherapy). In the present case, we detected lymph node (LN) metastasis only in LN#16, but not in LN#13 or LN#17. We believe that particle radiotherapy, consisting of proton and carbon-ion, can be used to control the lymphatic metastasis around the pancreas head and hepatoduodenal ligament. Our findings suggest that particle radiotherapy can be a standard neoadjuvant therapy for bile duct cancer.

Temporal information is essential for perception and behavior. Although the neural substrates for temporal processing have been elucidated in many different conditions, how individual neurons in each network represent time remains largely unknown. Here we review previous models of time representation in the brain, and propose that these models can be classified into four different groups based on two viewpoints. The first viewpoint is that temporal information is either prospective or retrospective. For example, the online control of movement timing requires prospective or predictive information, whereas the duration discrimination of previously presented stimuli depends on retrospective temporal information. The other viewpoint is whether neuronal coding is based on modulation of the firing rate in each neuron (rate coding) or the occurrence of synchronous activity across multiple neurons (temporal coding). The accumulator model and state-dependence model both represent time by modulating the rate of neuronal firing depending on the elapsed time, thereby providing the prospective and retrospective information, respectively. In contrast, temporal coding is used by the coincidence detection and entrainment/synchronization models acquired through learning. This classification might be helpful for comprehensive understanding of the neuronal mechanisms of temporal processing, each of which is implemented by the intrinsic property of each sensory system and/or by a dedicated network specialized for timing. We also propose a model incorporating serial stages of temporal processing to reproduce a fixed time interval, and suggest that future physiological and pharmacological experiments might prove our hypothesis.

We report a case of postoperative liver metastasis arising from pancreatic carcinoma treated with a novel procedure that we developed-percutaneous isolated hepatic perfusion (PIHP). A 69-year-old man diagnosed with pancreatic body cancer(pT3, pN0, pStage III) was treated using distal pancreatectomy and adjuvant therapy with gemcitabine(GEM). Six months later, a metastasis to the medial segment of the liver was found using computer tomography(CT). The patient was treated by chemotherapy with S-1, but the liver metastasis grew, and we therefore employed PIHP as the third-line therapy, using 80 mg doxorubicin (DXR) and 62 mg mitomycin C (MMC). Six weeks after PIHP, the tumor marker carbohydrate antigen 19-9( CA19-9) had decreased from 44,469 to 4,268 U/mL, and the carcinoembryonic antigen(CEA) level decreased from 28.8 to 5.4 U/mL. Although the size of the carcinoma remained the same on CT, some cells had liquefied as a result of necrosis. However, the patient died about 1 year after PIHP due to the growth of liver metastasis, peritoneal metastasis, and local recurrence, reflected by a progressively increasing level of tumor marker. In this case, PIHP seemed to be ineffective due to local recurrence and peritoneal metastasis as well as early enlargement of liver metastasis. However, the reduction in tumor marker levels and the observed tumor necrosis, suggest that PIHP is a potentially effective and promising treatment for liver metastasis arising from pancreatic carcinoma.

Local recurrences often develop after the resection of bile duct cancer. Imaging modalities do not have sufficient sensitivity or specificity to enable the definite diagnosis of recurrent bile duct cancer, and it may be difficult to decide when to start chemotherapeutic treatment. It is difficult to obtain specimens by conventional endoscopy after Roux-Y biliary reconstruction. The double-balloon endoscope(DBE) has 2 balloons: one at the tip of the endoscope and the other at the over- tube. The 2 balloons are inflated alternately and the endoscope can move through the small intestine in a caterpillar-like manner. DBE simplifies the approach to Roux-Y choledochojejunostomy and to obtaining a pathological specimen. Moreover, endoscopic biliary drainage and cholangiography can be performed with the DBE. Recently, the DBE has enabled systemic chemotherapy to be started after obtaining pathological evidence of malignancy, as well as biliary drainage instead of percutaneous transhepatic biliary drainage in cases with recurrent bile duct cancers. Here, we present 3 cases of recurrent bile duct cancer diagnosed and treated by a DBE.

A 69-year-old woman who had locally advanced pancreatic cancer underwent proton beam radiotherapy(67.5 GyE/25 Fr) concurrent with gemcitabine chemotherapy (GEM 800 mg/m2 day 1, 8) at Hyogo Ion Beam Medical Center, followed by GEM chemotherapy (1,000 mg/m2 day 1, 8, 15/28 day)at Kobe University Hospital. She visited our hospital because she was suffering from dyspnea 212 days after first administration of GEM. A chest computed tomography revealed that infiltrations were spreading in the bilateral lung fields. A bronchoscopy showed diffuse alveolar hemorrhage. We diagnosed GEM related interstitial lung disease with diffuse alveolar hemorrhage. We introduced steroid pulse therapy (methylprednisolone 1 g/day) for 3 days followed by oral prednisolone (40 mg/day), which was tapered gradually. She recovered and was discharged on the 24th day after admission.

Although the roles of the thalamocortical pathways in somatic movements are well documented, their roles in eye movements have only recently been examined. The oculomotor-related areas in the frontal cortex receive inputs from the basal ganglia and the cerebellum via the thalamus. Consistent with this, neurons in the paralaminar part of the ventrolateral (VL), ventroanterior (VA), and mediodorsal (MD) nuclei and those in the intralaminar nuclei exhibit a variety of eye movement-related responses. To date, the thalamocortical pathways are known to play at least 2 roles in eye movements. First, they are involved in the generation of volitional, but not reactive, saccades. Thalamic neurons discharge during anti-saccades, which are known to be impaired in several neurological and psychiatric disorders, such as Parkinson's disease, attention deficit/hyperactivity disorder, and schizophrenia. In addition, neurons in the thalamus also exhibit a gradual increase in firing rate that predicts the timing of self-initiated saccades. Recent inactivation experiments have established the causal roles of these thalamic signals in the generation of volitional saccades. Second, the thalamocortical pathways transmit the efference copy signals for eye movements. During inactivation of the MD thalamus, which relays signals from the superior colliculus to the frontal eye field (FEF), the accuracy of the saccade is reduced in tasks requiring efference copy signals. In addition, inactivation of the same pathways reduces the predictive visual response associated with saccades in neurons in the FEF. Moreover the VL thalamus has been reported to play a role in monitoring smooth pursuit. While the functional analysis of thalamocortical pathways in eye movements is just a beginning, the anatomical data suggest their important roles. Analysis of eye movement control may shed light on the functions of the thalamocortical pathways in general, and may reveal the neural mechanisms of cerebro-cerebellar, cerebro-basal ganglia, and cerebro-thalamic interactions.

A 73-year-old woman was referred to our hospital complainting of swelling of both eyelids and submandibular glands, nausea, and weight loss. She was given a diagnosis of autoimmune pancreatitis because of a marked elevation of serum IgG and IgG4 levels and diffuse swelling of the pancreas with stenosis of the main pancreatic duct. Biopsy obtained from the lachrymal gland revealed aggregated IgG4-positive plasma cells, leading to the diagnosis of Mikulicz's disease. PET-CT revealed an accumulation of FDG in the pancreas, lachrymal glands and submandibular glands, and lymph nodes in the mediastinum, hepatic hilium, bile duct and retroperitoneum. Three months after the initiation of steroid therapy, the serum levels of IgG and IgG4 decreased and FDG accumulations of the systemic lesions were no longer visible on PET.

The etiology and proper treatment of symptomatic subacute subdural hematomas remains to be elucidated. We describe two cases of this entity successfully treated with small craniotomy and evacuation. Both patients initially treated conservatively for traumatic thin subdural hematomas because of poor medical condition and mild neurological symptoms, but suffered abrupt neurological deterioration between 2 and 3 weeks after the admission. CT scan showed decreased density of hematomas with minimal increase in volume, and significant swelling of ipsilateral cerebral hemisphere. Urgent two-burr-hole small craniotomy was effective for evacuation of partially organized hematoma. During surgery, definite hematoma membrane was not confirmed. Postoperatively, brain swelling rapidly disappeared and both patients discharged ambulatory without neurological deficit. The present cases are a reminder of this peculiar type of hematoma in patients with delayed neurological deterioration after nonsurgical management of acute subdural hematoma. The rationale for use of small craniotomy is discussed in terms of current understanding of pathogenetic mechanism for this unusual condition.

We report a case of asymptomatic adrenal hematoma that enlarged during a 3-year follow-up. A 66-year-old woman exhibited a 4 cm right adrenal mass, incidentally discovered by computed tomography of abdomen, which progressively enlarged to 6 cm in diameter during the 3 years. The patient underwent right adrenalectomy with a diagnosis of a suspected non-functional adrenal tumor. Histopathological examination indicated adrenal hematoma without tumor cells. The patient had received aspirin medication for 4 years, and it is possible that the enlargement of the mass might have been due to aspirin medication.

A 72-year-old man presented with hemosputum and was admitted to our hospital. Computed tomography and osseous scintigraphy revealed right renal cancer and multiple pulmonary and osseous metastases. A translumbar nephrectomy was performed. The histopathological examination demonstrated granular cell carcinoma and clear cell carcinoma. The patient complained of dyspnea on postoperative day (POD) 16, and chest X-ray showed progression of the multiple pulmonary metastases and lymphangitis carcinomatosa. Betamethasone was administered for palliative treatment. After the treatment, dyspnea improved and chest X-ray on POD 57 showed disappearance of the multiple pulmonary metastases and improvement of lymphangitis carcinomatosa. Computed tomography and osseous scintigraphy confirmed complete regression of metastases. He has been free from recurrence for 16 months after the nephrectomy and for 13 months after the complete regression. To our knowledge, this is the first case of complete regression of metastatic renal cell carcinoma following corticosteroid treatment reported in Japan, and the second case when foreign literature is included.

A 16-year-old man presented with lumbago, perianal pain and constipation. A large tumor was palpable by digital rectal examination. Then, transrectal needle biopsies of the tumor were performed. Histopathological diagnosis was non-Hodgkin's malignant lymphoma (diffuse large B-cell type according to the new WHO classification). The results of some examinations were compatible with the diagnosis of primary lymphoma of the pararectal space. The patient underwent 2 courses of combination chemotherapy CHOP (consisting of cyclophosphamide, doxorubichin, vincristine, and prednisolone), and high-dose chemotherapy (ranimustine, etoposide, ifosfamide) with peripheral blood stem cell transplantation. After high-dose chemotherapy, radiation therapy was performed since there was a possibility of residual tumor, and complete remission was achieved. Now, 12 months after completion of the radiation, he remains free of the disease. This is probably the first clinical case of malignant lymphoma of the pararectal space ever reported in the Japanese literature.