Surface roughness of CP-Ti, Ti6Al4V and sputtered Ti specimen after oxygen plasma treatment for different lengths of time, respectively.

<p>Star sign means significant difference (<i>p</i> < 0.05).</p

Normalized XPS spectra of (a) CP-Ti, (b) Ti6Al4V and (c) sputtered Ti before and after oxygen plasma treatment for different lengths of time.

<p>Normalized XPS spectra of (a) CP-Ti, (b) Ti6Al4V and (c) sputtered Ti before and after oxygen plasma treatment for different lengths of time.</p

Water contact angles of CP-Ti and Ti6Al4V specimen treated by oxygen plasma.

<p>Water contact angles of CP-Ti and Ti6Al4V specimen treated by oxygen plasma.</p

Surface roughness of CP-Ti, Ti6Al4V and sputtered Ti specimen after oxygen plasma treatment for different lengths of time, respectively.

<p>Star sign means significant difference (<i>p</i> < 0.05).</p

Topographic images with section analysis of sputtered Ti substrates: (a) untreated, (b) OPT for 5 minutes, (c) OPT for 10 minutes and (d) OPT for 30 minutes.

<p>Topographic images with section analysis of sputtered Ti substrates: (a) untreated, (b) OPT for 5 minutes, (c) OPT for 10 minutes and (d) OPT for 30 minutes.</p

The results of MTT assay of CP-Ti and Ti6Al4V.

<p>In CP-Ti groups, star sign means significant difference; as well as Ti6Al4V groups, different letter meant statistic different. (<i>p</i> < 0.05).</p

The F-actin immunofluorescence staining of MG-63 cell line cultured on CP-Ti and Ti6Al4V (200x).

<p>(a) is CP-Ti, and (b) is Ti6Al4V. The blue ovoid to round dots was the portion of cell nuclei. The cell shape of CP-Ti Control was polygonal, as well as spindle shape of other groups. All cells cultured on Ti6Al4V displayed spindle shape.</p

Imaging Endogenous Bilirubins with Two-Photon Fluorescence of Bilirubin Dimers

On the basis of an infrared femtosecond Cr:forsterite laser, we developed a semiquantitative method to analyze the microscopic distribution of bilirubins. Using 1230 nm femtosecond pulses, we selectively excited the two-photon red fluorescence of bilirubin dimers around 660 nm. Autofluorescences from other endogenous fluorophores were greatly suppressed. Using this distinct fluorescence measure, we found that poorly differentiated hepatocellular carcinoma (HCC) tissues on average showed 3.7 times lower concentration of bilirubins than the corresponding nontumor parts. The corresponding fluorescence lifetime measurements indicated that HCC tissues exhibited a longer lifetime (500 ps) than that of nontumor parts (300 ps). Similarly, oral cancer cell lines had longer lifetimes (>330 ps) than those of nontumor ones (250 ps). We anticipate the developed methods of bilirubin molecular imaging to be useful in diagnosing cancers or studying the dynamics of bilirubin metabolisms in live cells