Probing Colloidal Gels at Multiple Length Scales:The Role of Hydrodynamics

Colloidal gels are out-of-equilibrium structures, made up of a rarefied network of colloidal particles. Comparing experiments to numerical simulations, with hydrodynamic interactions switched off, we demonstrate the crucial role of the solvent for gelation. Hydrodynamic interactions suppress the formation of larger local equilibrium structures of closed geometry, and instead lead to the formation of highly anisotropic threads, which promote an open gel network. We confirm these results with simulations which include hydrodynamics. Based on three-point correlations, we propose a scale-resolved quantitative measure for the anisotropy of the gel structure. We find a strong discrepancy for interparticle distances just under twice the particle diameter between systems with and without hydrodynamics, quantifying the role of hydrodynamics from a structural point of view.Comment: Phys. Rev. Let

Diagnostic value of serum EBV-DNA quantification and antibody to viral capsid antigen in nasopharyngeal carcinoma patients

医薬保健研究域医学系We compared the amount of serum Epstein-Barr virus DNA (EBV-DNA) detected in patients with nasopharyngeal carcinoma (NPC) in a high-incidence area, represented by Taiwan, and a low-incidence area, represented by Japan, using real-time quantitative PCR. The median serum EBV-DNA value in 41 Japanese NPC cases was 5450 copies/ml, and that in in 23 Taiwanese cases was 2125 copies/ml. The median serum EBV-DNA value in all 64 NPC cases was significantly higher than in control groups. Using receiver-operating-characteristic (ROC) curves, the sensitivity and specificity of EBV-DNA quantification were determined (cut-off point, 6.87 copies/ml; sensitivity, 0.855; specificity, 0.885) and compared with those of EBV-viral-capsid-antigen (VCA) titers; the results showed that EBV-DNA was a more sensitive and specific parameter than EBV-VCA titer. Then, we analyzed 19 NPC patients in whom recurrence developed (11 Japanese and 8 Taiwanese), and 26 NPC patients in continuous remission. Although there was no significant difference in EBV-DNA values between Japanese and Taiwanese patients, the value was significantly higher in the 19 patients with recurrence than in those in remission. ROC analysis again revealed a higher diagnostic value of EBV-DNA than EBV-VCA. These results suggest EBV-DNA is a more reliable tumor marker than EBV-VCA in both high-incidence and low-incidence areas of NPC

シンケイコン ショウガイ デ ハッショウシタ シンケイ サルコイドーシス ノ イチレイ

A５２-year-old woman was referred to our hospital for further examination of thoracolumbar pain. As dysesthesia at Th４level was seen in neurological examination, thoracic radiculopathy or myelopathy was suspected. Blood examination showed elevated level of serum ACE and lysozyme. Lymphadenopathy was evident in bilateral hila and mediastina with marked FDG and Gallium accumulation in FDG-PET-CT and Gallium scintigraphy, respectively. The number of lymphocytes and the CD４／CD８ratio were increased in the BALF. Histological findings of specimens obtained from the lung and the skin lesion revealed noncaseating epithelioid granuloma, which yielded the diagnosis of sarcoidosis. The cerebrospinal fluid examinations showed elevated level of cell counts, proteins and β２-microglobulin. Taken together, she was diagnosed as neurosarcoidosis with thoracic radiculopathy. Her symptoms were improved with oral administration of prednisolone, but they were exacerbated when prednisolone dose was tapered to２０mg／day. Combined therapy of methotrexate and prednisolone was initiated, thereafter her symptoms disappeared completely