A significant direct correlation could be found between inverse peritubular capillary blood flow and urinary L-FABP as well as the ischemic time of the transplanted kidney, and hospital stay. In human-L-FABP transgenic mice subjected to ischemia reperfusion injury, these transgenic mice after injury demonstrated lower blood urea nitrogen levels and less histological injury than injured wild-type mice, likely due to a reduction of tissue hypoxia. These data show that increased urinary L-FABP after ischemic-reperfusion injury may find future use as a biomarker of human renal microcirculation.

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Amyloid fibrils are considered to cause various serious amyloidoses including Alzheimer and prion diseases. Though their structures and mechanism of assembly have been recently studied extensively, denaturing condition of amyloid precursor protein and the process of amyloid fibril formation remain unclear. According to predicted molecular structure of amyloid fibrils, strong birefringence signals were expected to be observed when fibrils were aligned parallel. In order to investigate an incubation time dependence of amyloid fibril formation, flow induced birefringence was observed. Up to 3 hours of incubation, plateau birefringence value, Δn₀, increased with incubation time, while it leveled off for more than 3 hours. With the increase in Δn₀, rotational diffusion coefficient seemed to decrease synchronously. On the basis of these results, a model for amyloid fibrilogenesis was proposed.

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Osteoblasts are cells known to calcify extracellular matrices in bone by depositing hydroxyapatite (HAp) mineral particles. Only few reports have been published about HAp crystallization and matrix hardening process, though there have been many works on the cell differentiation and the response of cells to the external excitation at a gene level. The aim of this project was to investigate the crystallization process of HAp precipitated by osteoblasts in bone and to see when macroscopic reinforcement effect of extracellular matrix by HAp crystal particles becomes remarkable. For this purpose, we constructed an agarose gel-osteoblasts composite as a model system for bone generation. Culturing osteoblasts in the agarose gel, the time course of HAp crystallization and the reinforcement of composite by the precipitated HAp particles was investigated by means of Alizarin Red S staining, X-ray diffraction and stress-relaxation experiments. It was found that the reinforcement proceeded non-linearly, though HAp deposition and crystallization was almost proportional to the culture time. The result could be discussed on the basis of a percolation concept of HAp particles in agarose gel matrix.

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