Clinical characteristics and radiographic outcomes of vascular Behçet’s disease involving the aorta or its major branches

Clinical Rheumatology - To describe the clinical characteristics and radiographic outcomes of vascular Behçet’s disease (BD) involving the aorta or its major branches. This retrospective...     

A near-infrared photoinverter based on ZnO and quantum-dots

Near-infrared (NIR) photoswitching transistors have been fabricated using a hybrid structure of zinc oxide (ZnO) and quantum-dots (QDs). The ZnO active layer was prepared using a solution process, while colloidal QDs were inserted between a silicon dioxide (SiO₂) gate insulator and a ZnO active layer. The small band gap QDs (1.59 eV) were used to absorb low-energy NIR photons, generate photo-excited carriers, and inject them into the conduction band of the ZnO film. The device with the interfacial QDs induced photocurrents upon exposure to 780 nm-wavelength light. The photoresponsivity of the ZnO/QD device was 0.06 mA W⁻¹, while that of the device without QDs was 1.7 × 10⁻⁵ mA W⁻¹, which indicated that the small band gap QDs enabled a photo-induced current when exposed to NIR light. Furthermore, a photoinverter was prepared which was composed of a ZnO/QDs phototransistor and a load resistor. Photoswitching characteristics indicated that the photoinverter was well modulated by a periodic light signal of 780 nm in wavelength. The results demonstrate a useful way to fabricate NIR optoelectronics based on ZnO and QDs.

A near-infrared photoinverter was fabricated based on ZnO and quantum-dots. We found that the small band gap quantum-dots could absorb low-energy near-infrared photons, generate photo-excited carriers, and inject them into the conduction band of ZnO.     

Leptin receptors are down-regulated in uterine implantation sites compared to interimplantation sites

Leptin is a circulating hormone that plays an important role in the regulation of metabolism, obesity, and reproduction. Leptin binds to its receptors on the cell membrane and is involved in the activation of STAT3. Recently, endometrium was suggested to be a novel target for leptin recently. We, therefore, examined the expression of leptin, leptin receptors, and STAT3 in the mouse uterus (implantation and interimplantation sites) to investigate the role of the leptin system during the early implantation period. Leptin mRNA was not detected in mouse uterine tissues or blastocysts, although adipose tissue, the positive control, showed a strong signal. Both of the receptor splice variants were expressed in the uterus and blastocysts, but the mRNA level was much lower in implantation sites compared to interimplantation sites. The mRNA expression of leptin receptors was determined to be higher in stromal cells than in the luminal epithelium using laser capture microdissection (LCM) analysis. Using immunohistochemistry, leptin was detected as a strong signal in the luminal epithelium and embryo, whereas the receptor was detected in subepithelial stromal cells rather than the luminal epithelium. As leptin itself was not detected by RT-PCR, the immunohistologically detected leptin may originate elsewhere, such as in adipose tissue. The differential expression of leptin receptors in implantation sites compared to interimplantation sites suggests that the leptin/leptin receptor system may be a delicate regulator of the implantation process.     

The role of interferon in virus-induced diabetes

The repeated administration of interferon (IFN) or an IFN inducer reduced the development of diabetes in mice infected with the D variant of encephalomyocarditis (EMC) virus. Mice treated with the IFN inducer had less infectious virus, fewer pathologic changes, and higher concentrations of immunoreactive insulin in the islets of Langerhans in comparison with untreated mice. Antibody to mouse IFN (MuIFN) suppressed circulating IFN in mice infected with the B variant of EMC virus. Mice treated with antibody to MuIFN had four times more infected islet cells and 10 times more infectious virus in the pancreas compared with untreated mice. Of the surviving animals treated with antibody to MuIFN, approximately 40% developed mild diabetes whereas none of the mice developed diabetes when infected with the B variant of EMC virus alone. The IFN system is an important determinant of the outcome in EMC virus-induced diabetes in mice.     

Diagnosis of tricuspid regurgitation. Current status

The most accepted diagnostic methods of tricuspid regurgitation (TR) are the physical examinations and the evaluation of right atrial pressure. However, these methods are not consistently diagnostic, and a "silent" form of TR has been recognized. The current status of noninvasive and invasive diagnostic techniques is reviewed.     

Determination of the need for tricuspid valve replacement: value of preoperative right ventricular angiocardiography

Of 530 patients undergoing tricuspid valve surgery from January 1, 1961 through December 31, 1987, those 362 patients having had preoperative right ventricular angiocardiography were studied. Mean age was 58.5 years. There were 71 males and 291 females. Tricuspid valve replacement (TVR) was performed in 126 (34.8%), and 236 underwent tricuspid valve repair (65.2%). The predominant pathology was combined tricuspid insufficiency and stenosis in 18 patients (4.9%), and isolated tricuspid insufficiency in 344 (95.1%). There were no complications related to the right ventriculogram. Preoperative angiographic severity of tricuspid valve incompetence was grade 1 in 23 patients (6.4%), grade 2 in 65 (17.9%), grade 3 in 109 (30.1%), and grade 4 in 165 (45.6%). Intraoperative assessment of the severity of tricuspid valve incompetence correlated 72% of the time with the preoperative angiographic assessment, in those patients with more severe degrees of incompetence (grade 3+ or 4+), p (X 2) less than 0.001. Increasing severity of preoperative angiographic triscuspid valve incompetence was associated with the requirement for TVR (vs. repair), p (X 2) = 0.0002. In conclusion, preoperative right ventricular angiography is a useful method for assessing tricuspid valve function and may predict the requirement for TVR in patients undergoing tricuspid valve surgery.