Infrared radiative switching with thermally and electrically tunable transition metal oxides-based plasmonic grating.

Plasmonic and phase transition has been blended to gain the infrared radiative switching which is tunable with temperature or voltage supply. This is applied via vanadium dioxide, tungsten trioxide, and molybdenum trioxide as transition metal oxides (TMO). The metallic phase at high temperature or colored state contributes in magnetic polariton (MP) excitation, producing broad absorptance. The TMO-based sub-layer is integrated underneath the grating fully supporting MP resonance. In contrast, this underlayer leads to producing the narrowband absorptance originated from concept of zero contrast grating (ZCG). The zero gradient in refractive index at the output plane of the grating cause transmission of light in broad wavelength range. With introduction of reflective silver underlayer, those transmitted through the grating are reflected back. However, there exists the near-zero narrowband transmission peaks in ZCG. This undergoes transformation to narrowband absorptance. In addition, another absorptance peak can be induced due to phonon modes at insulating phase. The MP resonance at metallic phase is characterized with inductor-capacitor (LC) circuit and the narrowband absorptance peaks are characterized with phase shift from the Fabry-Perot round trip (FP-RT) eigenequation from high contrast grating (HCG). The work expands the usage of transition metal oxides in infrared region with larger contrast.

Plasmon-resonance emission tailoring of "origami" graphene-covered photonic gratings.

Due to the negative coefficient of thermal expansion of graphene, temperature changes of graphene-coated photonic surfaces could induce resonant mode shifts in diffractive optical absorptance and emission. This study focuses on the modification of optical properties through folding, or "origami," of graphene covering a plasmonic metal channel grating. This work is especially critical to understanding tailored deep plasmon emission from geometrically-modulated conducting sheets such as graphene. Conformational changes in graphene on gratings are found to tailor cavity resonance emission and plasmonic oscillations such as magnetic polaritons (MPs) and surface plasmon polaritons (SPPs), respectively. Up to 46% reduction in radiative absorptance was observed through retarded MP. Excited SPP modes can increase narrowband absorptance of 0.5 through folding of graphene. Tailoring of optical absorptance can be used for applications such as photodetectors and thermal emitters.

Case reports of unexpected suicides in patients within six months after stroke.

Suicide after stroke is a grievous occurrence. Since the majority of cases under study had shown signs of recovery from stroke, persons surrounding these patients were severely shocked by these suicides. Six patients who attempted suicide within six months after stroke were investigated to determine factors following stroke that relate to suicide in order to prevent future post-stroke suicides. Clinical findings in these six cases were retrospectively analyzed in collaboration with stroke neurologists and coworkers caring for these patients. Four of six patients had sustained a recent infarction extending from the temporal cortex to the parietal cortex. Four of six patients showed depression, and five of six patients showed moderate disability after stroke. Physicians should carefully observe patients with infarction extending from the temporal cortex to the parietal cortex, depression and moderate disability, in order to prevent suicidal behavior.

Gastric bleeding from a penetrating pancreatic pseudocyst with pseudoaneurysm of the splenic artery.

The successful management of gastric bleeding from a pseudocyst with a pseudoaneurysm of the splenic artery is reported here. A 62-year-old male patient was referred to our hospital with a complaint of hematomesis. On a computed tomography and an abdominal angiography, it was evident that he was actively bleeding from a splenic pseudoaneurysm caused by a pancreatic pseudocyst. A transcathetheral arterial embolization (TAE) was performed on the splenic pseudoaneurysm to control bleeding. After the TAE, we resected the pancreatic pseudocyst by distal pancreatectomy with partial gastrectomy. Gastrointestinal bleeding from a pseudoaneurysm caused by a pancreatic pseudocyst is a rare, but sometimes lethal, complication. As only conservative therapy or TAE often results in lethal re-bleeding, we propose to perform elective surgery after TAE.

Macrocystic serous cystadenoma mimicking branch duct intraductal papillary mucinous neoplasm.

A 29-year-old woman was referred to our hospital with a pancreatic cystic tumor diagnosed by computed tomography and magnetic resonance imaging. Endoscopic retrograde cholangiopancreatography was performed, wherein macrocystic serous cystadenoma of the pancreas was diagnosed. It was decided to observe the progress of the disease. The tumor diameter increased over 18 months to > 50 mm. Its growth rate was slower than the average rate of serous cystadenoma described in previous reports, but its form become warped and shaped like bunches of grapes. A branch duct variant of intraductal papillary mucinous neoplasm could not be excluded. Laparoscope-assisted distal pancreatectomy was performed, and the pathological diagnosis was macrocystic serous cystadenoma. Some macrocystic serous cystadenomas are like an intraductal papillary mucinous neoplasm, and differential diagnosis is very difficult. The macrocystic serous cystadenoma is a rare lesion, but it should be considered when diagnosing cystic tumors of the pancreas.

A case of retroperitoneal mucinous cystadenoma treated successfully by laparoscopic excision.

A case of retroperitoneal mucinous cystadenoma treated laparoscopically is reported. A 26-year-old woman, who complained of abdominal fullness, was referred to us after a large intra-abdominal mass was discovered at her local hospital. Ultrasound and computed tomography showed a fluid-filled mass, 9 cm in diameter, in the left retroperitoneal space. Laparoscopic surgery was performed. We found a smooth and thin-walled cystic tumor that displaced the descending colon to the right and arose from the retroperitoneum, loosely adhering to the psoas muscle. We successfully extirpated the tumor laparoscopically. The surgical specimen consisted of a multilocular, red to yellowish-gray, cystic mass with a smooth, glistening external surface, and inner lining. The mass was filled with thin, yellowish fluid. The histologic diagnosis was benign mucinous cystadenoma. The postoperative course was uneventful, and the patient remains free of recurrence 15 months after surgery. Retroperitoneal mucinous cystadenoma is a rare entity, and the treatment of choice is surgical excision. Laparoscopic extirpation should be considered for the treatment of selected retroperitoneal cystic lesions.

Lymphoepithelial cyst of the pancreas: report of a case.

The aim of this report is to describe the clinical and pathological features of a lympoepithelial cyst of the pancreas and to recommend fine-needle aspiration biopsy for the differential diagnosis of this lesion. A 55-year-old man was incidentally diagnosed as having a pancreatic tumor by abdominal ultrasonography. A hypoechoic cystic lesion was detected on the surface of the pancreatic body. A computed tomography revealed a cystic lesion surrounded by a smooth, flat wall. Magnetic resonance imaging revealed that the lesion was a low-intensity mass on the T1-image and a slightly high-intensity mass on the T2-image. The lesion was diagnosed as a benign cystic tumor, and enucleation of the tumor was scheduled. The fine needle aspiration biopsy was performed after laparotomy, and cytology of the contents was negative for malignant cells. The postoperative pathological diagnosis was a lymphoepithelial cyst of the pancreas. This cyst is an unusual but benign mass that requires minimal surgery.

Clinicopathological characteristics and outcome indicators of stage II gastric cancer according to the Japanese classification of gastric cancer.

BACKGROUND: The characteristics of stage II gastric cancer according to the Japanese Classification of Gastric Cancer (JCGC) were examined and the high-risk factors predicting poor prognosis were detected. PATIENTS AND METHODS: In total, 107 patients, who underwent clinically curative gastrectomy with D2 lymphadenectomy for stage II gastric cancer, were included. Survival curves of the depth of invasion, lymph node metastasis, the ratio of involved: resected lymph nodes and chemotherapy treatment were compared. RESULTS: The survival curves were related to tumor invasion depth and lymph node metastasis. The ratio of involved resected lymph nodes was a good prognostic indicator compared to the classification of regional lymph node metastasis (N classification). Survival rates with adjuvant chemotherapy were slightly higher than without adjuvant chemotherapy, but the difference was not significant. CONCLUSION: pT2pN1 (stage II) gastric cancers according to the JCGC, especially pSSpN1 cases, included stage IIIB and IV gastric cancers according to the International Union Against Cancer / American Joint Committee on Cancer (UICC/AJCC); therefore, the prognosis of these might be poor. With pSSpN1 cases, according to the JCGC, anticancer chemotherapy equivalent to that required for stage III gastric cancer cases is necessary.

Imaging of distal internal carotid artery by ultrasonography with a 3.5-MHz convex probe.

BACKGROUND AND PURPOSE: Conventionally, carotid ultrasonography has been performed with a 7.5-MHz linear probe to evaluate the extracranial internal carotid artery (ICA). However, usually only the carotid bulb or proximal portion of the ICA can be evaluated. We attempted to evaluate the distal extracranial ICA with a 3.5-MHz convex probe. METHODS: The subjects were 17 consecutive patients with ICAs free of occlusive disease and 3 other patients with distal extracranial ICA stenosis. Using a 7.5-MHz linear probe and a 3.5-MHz convex probe, we performed long-axis B-mode imaging of the ICAs to evaluate the distance between the distal limit of visualized ICA and the bifurcation of the common carotid artery. RESULTS: The distal limit of the ICA, visualized with a 7.5- or a 3.5-MHz probe, was 31+/-11 or 57+/-8 mm distal to the common carotid artery bifurcation, respectively. In the 3 patients with distal extracranial ICA stenosis, the lesion could be successfully diagnosed with only the 3.5-MHz probe. CONCLUSIONS: This form of carotid imaging is feasible and may be potentially useful in the evaluation of carotid disease.