Thermal near-field scattering characteristics for dielectric materials.

In this study, we passively analyzed the near-field characteristics of thermally excited evanescent waves, which are radiation waves generated by the local dynamics of materials, including electron motions and lattice vibrations. The thermally excited evanescent waves on aluminium nitride (AlN) and gallium nitride (GaN) were measured using passive spectroscopic scattering-type scanning near-field optical microscopy (s-SNOM) in the wavelength ranges of 10.5-12.2 µm and 14.0-15.0 µm, which include the surface phonon-polariton (SPhP) wavelength of the studied dielectrics. We determined the unique decay characteristics of AlN and GaN, indicating a ten-fold increase in the probe area contributing to the scattering of waves near the SPhP wavelength compared to that in other wavelength ranges. The extended probe area correlated with the polariton decay lengths, indicating that the non-enhanced polaritons around K ~ ω/c were dominant in the scattered waves near the SPhP wavelength. In addition to the conventional passive detection mechanisms for metals, the proposed detection scheme will be a versatile passive detection model in the near future.

Relationship between clotting activity and phosphatidylserine expression on erythrocyte membranes in polycythemia vera patients with the JAK2 V617F mutation.

INTRODUCTION: Polycythemia vera (PV) accompanies the clinical course of thrombosis. Phosphatidylserine (PS) expression on the plasma membrane has been known to be one of place where the coagulation system activates. We studied the relationship between clotting factor activity and PS expression on the erythrocyte membrane in patients with erythrocytosis. METHODS: The coagulation test and PS expression in 23 patients with erythrocytosis were measured. PS expression was determined indirectly by measuring annexin V binding to erythrocytes using fluorescence activated cell sorter analysis (FACS). RESULTS: The activity of clotting factors (II, V, VII, VIII, von Willebrand factor, IX, X) was significantly lower in PV than in the mutation-negative erythrocytosis. There was a significant correlation between reduced activity of clotting factors such as V, X, and IX and increased PS expression of the erythrocyte membrane. CONCLUSION: Increased expression of PS on the erythrocyte membrane may reduce the activities of clotting factors in PV patients with JAK2 V617F mutation.

[Low-titer cold agglutinin disease following Salmonella gastroenteritis].

We encountered a patient with cold agglutinin disease (CAD) that worsened after Salmonella gastroenteritis. A 52-year-old male complained pain in the left fingers with cyanosis and was admitted in a local hospital. After treatment for ischemia, he demonstrated diarrhea with fever. Because of progressive anemia, he was referred to our hospital. Salmonella gastroenteritis was diagnosed based on the results of microbiological examination. Severe hemolysis was noted at admission, and Coombs test was positive (IgG-, C3d+). Cold agglutinin titer was elevated (x256). There were no findings of malignancy or infection demonstrating CA. A diagnosis of CAD with Salmonella gastroenteritis was made. Because spherocytosis was noted during admission, we measured the mean channel fluorescence (MCF) of eosin-5-maleimide (EMA) in erythrocytes from patients. MCF of EMA of the patient's erythrocytes was similar to that of normal subjects. Therefore, we concluded that coexisting hereditary spherocytosis was unlikely. We also examined the in vitro hemolytic effect of Salmonella infection on his blood and on blood from normal subjects. Treatment with Salmonella enteritidis isolated from this patient was found to induce hemolysis in the patient's blood, but not in blood from a normal subject. Moreover, treatment with Salmonella increased the titer of cold agglutinin in vitro. These data suggested that Salmonella infection might worsen hemolysis in CAD.