Photo-designed terahertz devices.

Technologies are being developed to manipulate electromagnetic waves using artificially structured materials such as photonic crystals and metamaterials, with the goal of creating primary optical devices. For example, artificial metallic periodic structures show potential for the construction of devices operating in the terahertz frequency regime. Here we demonstrate the fabrication of photo-designed terahertz devices that enable the real-time, wide-range frequency modulation of terahertz electromagnetic waves. These devices are comprised of a photo-induced, planar periodic-conductive structure formed by the irradiation of a silicon surface using a spatially modulated, femtosecond optical pulsed laser. We also show that the modulation frequency can be tuned by the structural periodicity, but is hardly affected by the excitation power of the optical pump pulse. We expect that our findings will pave the way for the construction of all-optical compact operating devices, such as optical integrated circuits, thereby eliminating the need for materials fabrication processes.

Direct creation of a photoinduced metallic structure and its optical properties in the terahertz frequency region.

We investigate the surface electromagnetic characteristics of a photoinduced periodical structure using the attenuated total reflection (ATR) technique in the terahertz frequency region. A wire grating structure is generated at the surface of a silicon prism by irradiation with a spatially modulated, ultrafast pulsed laser. A characteristic minimum due to the excitation of surface waves is observed in the ATR spectrum. The depth profile of the photoinduced carrier layer is also studied. We confirm that the photoinduced structure has metallic properties. This fabrication technique will be developed as a simple method to create "active" structures.

A case of atypical thyroid storm with hypoglycemia and lactic acidosis.

We describe herein a case of thyroid storm with hypoglycemia and lactic acidosis-a rare complication of thyroid storm. The patient was a 50-year-old Japanese woman who suffered cardiopulmonary arrest an hour after hospitalization. Analysis of a blood sample obtained before her cardiopulmonary arrest yielded surprising results: Her plasma glucose level was 14 mg/dL and her lactic acid concentration had increased to 6.238 mM. Thus, if atypical thyroid storm presents with normothermic hypoglycemia, and lactic acidosis, we believe it is necessary to consider a diagnosis of thyroid storm earlier, because this condition requires emergency treatment. Moreover, it is very important to apply standard principles in the treatment of atypical cases of thyroid storm.

Resonant phase jump with enhanced electric field caused by surface phonon polariton in terahertz region.

We investigated surface phonon polariton in cesium iodide with terahertz time-domain attenuated total reflection method in Otto configuration, which gives us both information on amplitude and phase of surface electromagnetic mode directly. Systematic experiments with precise control of the distance between a prism and an active material show that the abrupt change of pi-phase jump appears sensitively under polariton picture satisfied when the local electric field at the interface becomes a maximum. This demonstration will open the novel phase-detection terahertz sensor using the active medium causing the strong enhancement of terahertz electric field.

[Case of multiple vertebral osteomyelitis due to Streptococcus pneumoniae].

We report a rare case of multiple vertebral osteomyelitis due to Streptococcus pneumoniae. A 73-year-old man admitted for back pain and a low-grade fever was found in laboratory studies to have severe leukocytosis and increased C-reactive protein, but neither computed tomography (CT) nor vertebral magnetic resonance imaging (MRI) clarified the cause of infection in the painful hip lesion, and paralysis developed. in the left leg MRI eventually indicated a vertebral abscess involving multiple lesions at C4-7 and L4-5. We had started antibiotics before blood culture clarified Streptocccus pneumonaie, and antibiotics acted more effectively thereafter. The clinical course was good, little paralysis remained.

Coexistence of bound and localized exciton magnetic polarons in Cd(0.8)Mn(0.2)Te.

Fundamental magneto-optical properties of single crystals of the semimagnetic semiconductor Cd(0.8)Mn(0.2)Te are carefully measured with the use of band-to-band excitation. Two new phenomena are presented: the peculiar magnetic field dependence of the magnetic polaron luminescence and the existence of two components for the polaron luminescence. Theoretical consideration with regard to the Zeeman effect ascribes the two components of luminescence to the exciton magnetic polaron spectrum and the neutral acceptor-bound exciton magnetic polaron spectrum. The calculated result for the luminescence peak positions is also consistent with the experimental result of the circularly polarized luminescence under the presence of an applied magnetic field. In other words, the σ(+) luminescence is due to the exciton magnetic polaron, whereas the σ(-) luminescence is due to the neutral acceptor-bound exciton magnetic polaron.

Activation of TGF-beta/Smad2 signaling is associated with airway remodeling in asthma.

BACKGROUND: Transforming growth factor beta (TGF-beta) has been suggested to play an important role in the development of airway remodeling in asthma; this suggestion is based on evidence that expression levels of TGF-beta are correlated with unique parameters of airway remodeling, such as thickness of basement membrane. However, the relevant studies were inconclusive because they were unable to demonstrate active signaling mediated by the cytokine in the airways of asthmatic individuals. OBJECTIVE: We sought to determine whether TGF-beta signaling was active in the airways of asthmatic subjects and, if so, whether it was correlated with clinicopathologic features associated with the development of airway remodeling in asthma. METHODS: We examined the phosphorylation status of Smad2 in bronchial biopsy samples obtained from 40 asthmatic subjects as a marker of active TGF-beta signaling, and we studied its correlation with basement membrane thickness. RESULTS: Expression levels of phosphorylated Smad2 in bronchial biopsy specimens from asthmatic subjects were higher than those in specimens from normal subjects, and they were correlated with basement membrane thickness in asthma. CONCLUSION: The findings provide evidence that TGF-beta signaling was active in asthmatic airways and that the activity was associated with the development of airway remodeling in asthma.

[Community acquired sepsis by Serratia rubidaea].

A 48-year-old male who had a past history of alcoholic pancreatitis and diabetes mellitus was admitted to our hospital due to chills and vomiting, on August 13, 1998. His body temperature was 38.0 degrees C, and he had the disturbance of consciousness, tachypnea, tachycardia and hepatomegaly with tenderness. Laboratory findings showed highly inflammatory reactions, DIC and hepatorenal dysfunction. Abdominal CT and US revealed multiple liver abscess with portal vein thrombus. Serratia rubidaea was detected in the blood culture. SBT/CPZ and TOB were administered and he recovered. This is a rare case of Serratia rubidaea sepsis. It is also necessary to pay attention to Serratia infections as well as S. marcescens.