Electron-beam induced terahertz radiation from graded metallic grating.

We have numerically analyzed, based on a simplified particle-in-cell finite-difference time-domain (PIC-FDTD) method, an electron-beam (e-beam) induced terahertz (THz) radiation from metallic grating structures with graded depths (graded grating). Upon exciting with e-beam, directional THz radiations with wide-band spectrum containing several sharp peaks are obtained only from the one of the edge of the grating, which cannot be expected from the conventional theory of Smith-Purcell radiation. It was clarified that each modes originate from different locations on the graded grating reflecting different dispersion characteristics of spoof surface plasmon polariton (spoof SPP) at each locations, and they can propagate toward only the shallower groove as a surface wave due to the cutoff at each locations, and all of these modes eventually emitted from the one of the edge of the graded grating. These directional radiations can be directed toward either backward or forward by making the groove depth deeper or shallower. The lowest and the highest frequency of the radiation can be chosen by appropriately designing the deepest and the shallowest groove depths, respectively. These unique radiations cannot be obtained from the uniformly grooved grating. Our findings may open the way for a development of novel THz radiation source based on the spoof SPP on the wide variety of metallic grating structures or metasurfaces.

Total palliative care for a patient with multiple cerebral infarctions that occurred repeatedly in association with gastric cancer (Trousseau's syndrome).

OBJECTIVE: Malignancy-related thromboembolism, also referred to as Trousseau's syndrome, can present as acute cerebral infarction, nonbacterial thrombotic endocarditis (NBTE), and migratory thrombophlebitis. Therefore, many physical, neurological, and psychological symptoms associated with Trousseau's syndrome may occur in the clinical course. METHOD: To illustrate this, we report a case of a male patient in his 50s with carcinomatous peritonitis caused by gastric cancer, with multiple cerebral infractions that developed during disease progression. The patient was admitted to our hospital for the treatment of side effects of chemotherapy, although he strongly hoped to go home as soon as possible. In addition to making social supports plans, we were required to perform intensive total palliative care, because of his physical pain, general fatigue, anorexia, abdominal and neck pain, and psychological issues (insomnia, delirium, depression, suicidal thoughts, self-mutilation, panic attacks, agoraphobia, fear of death, and feelings of hopelessness). RESULTS: To the best of our knowledge, based on the literature search, this is the first reported case of Trousseau's syndrome described in the context of total palliative care, especially psychological care. SIGNIFICANCE OF RESULTS: We propose that neurological symptoms of Trousseau's syndrome cause these extensive mental disorders. Furthermore, because of the prognosis of Trousseau's syndrome, we should utilize our expertise fulfill the patient's wishes.

Retroperitoneal solitary fibrous tumor-induced hypoglycemia associated with high molecular weight insulin-like growth factor II.

A man, aged 65 years, presented with frequent episodes of hypoglycemia and unconsciousness. Hypoglycemia was accompanied by undetectable serum insulin and C-peptide levels and a high serum insulin-like growth factor (IGF)-II level. He was found to have a retroperitoneal solitary fibrous tumor. He underwent successful resection of the tumor and had no hypoglycemic episodes after the operation. Immunohistochemical analysis revealed positive immunostaining for IGF-II in tumor cells. The presence of the high-molecular-weight form of IGF-II in the patient's serum was confirmed by immunoblotting, which suggests that his hypoglycemia was due to an increase in the plasma level of IGF-II secreted by the tumor.

[Complete remission of hepatic metastasis of gastric cancer with CPT-11].

We treated hepatic metastasis of gastric cancer with CPT-11 therapy and obtained complete remission of the hepatic tumor that has been maintained for than 2 years postoperatively. The patient was a 71-year-old man with a history of angina pectoris. In 1988, gastric cancer was diagnosed, and he underwent distal gastrectomy at another hospital. In 2003, the patient began to suffer from regurgitation symptoms and presented to our hospital in October of the year. Remnant gastric cancer was diagnosed as a result of detailed investigation. Preoperative imaging revealed the presence of a solitary tumor (6 cm in diameter) in the posterior lobe of the liver, and it was confirmed to be a hepatic metastasis from the remnant gastric cancer by needle biopsy. We decided to treat this metastasis with postoperative systemic chemotherapy. Total resection of the remnant stomach was done in November 2003 and oral S-1 therapy was started 3 weeks after surgery. When the response of the hepatic metastasis was evaluated after the completion of 3 courses, the tumor showed enlargement. Therefore, his chemotherapy was changed to CPT-11. After a total 900 mg of CPT-11 had been administered, imaging studies confirmed disappearance of the hepatic metastasis. The patient remains disease-free and has no impairment of daily activities 2 years after resection of the remnant stomach.

Optimization of a coagulation factor VIIa inhibitor found in factor Xa inhibitor library.

An inhibitor of the complex of factor VIIa and tissue factor (fVIIa/TF), 2-substituted-4-amidinophenylpyruvic acid 1a, was structurally modified with the aim of increasing its potency and selectivity. The lead compound 1a was originally found in our factor Xa (fXa) inhibitor library on the basis of structural similarity of the primary binding sites of fVIIa and fXa. The design was based on computational docking studies using the extracted active site of fVIIa. Compound 1j was found to inhibit factor VIIa/TF at nanomolar concentration with improved selectivity versus fXa and thrombin and it preferentially prolonged the clotting time in the TF-dependent extrinsic pathway.