Background Peritoneal metastasis is the most frequent pattern of recurrence after curative surgery for gastric cancer. However, such a recurrence is difficult to detect by conventional computed tomography (CT) and magnetic resonance imaging (MRI) at an early stage. To improve the sensitivity and specificity of diagnostic imaging for peritoneal metastasis, we developed a new type of multimodality imaging combining fluorescence imaging with nearinfrared fluorophore (NIR)-labeled antibodies and MRI. Methods Dual optical imaging of peritoneal metastasis was carried out using luciferase-tagged gastric cancer cell lines and XenoLight CF750 or indocyanine green (ICG)-labeled anti-human epidermal growth factor receptor (EGFR) or CEA antibody as a probe in mice with Ivis in vivo imaging system.Results This whole-body fluorescent imaging system sensitively detected metastatic foci \1 mm in diameter in the peritoneal cavity noninvasively. Fluorescence imaging proved to be specific because the fluorescence signal was abolished by blocking with excess unlabeled antibody. Although this fluorescence imaging had higher sensitivity for detection of small-sized peritoneal metastases than MRI, it proved difficult to accurately determine organ distribution of the metastasis. We thus developed a multimodality imaging system by the fusion of the threedimensional fluorescence image with the MRI image and demonstrated its improved diagnostic accuracy over either method alone. Conclusion The present results suggest that multimodality imaging consisting of fluorescence imaging with NIRlabeled EGFR or CEA antibody and MRI allows sensitive, specific, and anatomically accurate detection of peritoneal metastasis noninvasively at an early stage.

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Maximum gait speed and physical activity (PA) relate to mortality and morbidity, but little is known about gender-related differences in these factors in elderly hospitalized cardiac inpatients. This study aimed to determine differences in maximum gait speed and daily measured PA based on sex and the relationship between these measures in elderly cardiac inpatients.A consecutive 268 elderly Japanese cardiac inpatients (mean age, 73.3 years) were enrolled and divided by sex into female (n = 75, 28%) and male (n = 193, 72%) groups. Patient characteristics and maximum gait speed, average step count, and PA energy expenditure (PAEE) in kilocalorie per day for 2 days assessed by accelerometer were compared between groups.Gait speed correlated positively with in-hospital PA measured by average daily step count (r = 0.46, P < 0.001) and average daily PAEE (r = 0.47, P < 0.001) in all patients. After adjustment for left ventricular ejection fraction, step counts and PAEE were significantly lower in females than males (2651.35 ± 1889.92 vs 4037.33 ± 1866.81 steps, P < 0.001; 52.74 ± 51.98 vs 99.33 ± 51.40 kcal, P < 0.001), respectively.Maximum gait speed was slower and PA lower in elderly female versus male inpatients. Minimum gait speed and step count values in this study might be minimum target values for elderly male and female Japanese cardiac inpatients.

We have studied saturation transfer in hydrophilic, cross-linked copolymer gels from irradiated polymer protons to observed water protons, using f2 (ppm) profiles of [1 - (I(infinity)/I(0))], [(I(0)/I(infinity)) - 1] or 1/T(IS)(H2O), where I(0) and I(infinity) are the longitudinal magnetization of the observed water protons before and after long-time-f2-irradiation on polymer protons, respectively, and 1/T(IS)(H2O) is the cross-relaxation rate. (A) [1 - (I(infinity)/I(0))] (magnetization transfer ratio, MTR) was used in magnetic resonance imaging (MRI) as the MTR imaging. 1/T(IS)(H2O) (cross-relaxation rate) was used in the imaging of the magnetization transfer rate constant. This method was quite time-consuming compared with MTR imaging. However, f2 (ppm) profiles of [(I(0)/I(infinity)) - 1] correlated well with corresponding profiles of 1/T(IS)(H2O), because [(I(0)/I(infinity)) - 1] is equal to 1/[T(IS)(H2O)/T1(H2O)]. These results lead us to the conclusion that [(I(0)/I(infinity)) - 1] might be applicable to cross-relaxation rate (CR)-like imaging, i.e. equivalent CRI. (B) W (%) (dry weight) profiles of [(I(0)/I(infinity)) - 1] and 1/T(IS)(H2O), obtained by near-resonance f2-irradiation, seem to indicate participation of molecular rigidity and an amount of bound water. However, those values, monitored with off-resonance f2-irradiation, seem to be independent of monomer composition and to indicate mainly participation of rigidity, i.e. W (%) of copolymer gels.

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Sentinel lymph node biopsy (SLNB) is an important technique for detecting axillary lymph node metastasis in breast carcinoma patients. However, false-negative results are a problem. Equivalent cross-relaxation rate (ECR) imaging (ECRI) is a measurement method that can be used to quantitatively evaluate a change in the structural organization of lymph nodes by magnetic resonance imaging (MRI). We performed axillary ECRI in an attempt to decrease the false-negative results of SLNB. Regions without metastases showed a higher ECR value. On the other hand, regions with metastases showed a lower ECR value. The ECR images were compared with macroscopic histology images in which the presence or absence of axillary lymph node metastasis could be evaluated. ECRI is a potentially useful method for evaluating the efficacy of SLNB. Over the past few years, breast conservation surgery has become a standard procedure for the operative management of early breast cancer. The sentinel lymph node (SLN) biopsy (SLNB) is fast becoming the technique of choice to determine whether breast cancer has spread to the lymph ducts or nodes. The only time an SLNB is bypassed is when there is significant evidence of clinical involvement of one or more axillary nodes. However, involvement of the axillary nodes with metastatic carcinoma can lead to mechanical obstruction of the lymphatic sinuses and alterations in fluid transport, which in turn may lead to a false-negative result if a radio-tracer or dye approach is used (1).Magnetic resonance (MR) lymphography is used to localize SLNs in breast cancer, and some studies that used contrast agent have been reported (2-6). Off-resonance saturation imaging is an MRI technique that selectively alters the contrast on the basis of tissue macromolecular environments by magnetization transfer and spin lock (7,8), and the contrast obtained is highly dependent on the offset frequency (7-10). In saturation transfer ratio imaging (STRI), the contrast obtained in the breast cancer tissue at frequency offsets of 7 and 19 ppm from the water resonance frequency has been shown to correlate with the malignant potential of the cells and the extent of fibrosis, respectively (11). In an in vitro nuclear magnetic resonance (NMR) study, Callicot et al. (12) found that the cross-relaxation rate is a more sensitive parameter than the STR for characterizing human breast tissue. The crossrelaxation rate (1/T IS ) is defined as the magnetization transfer rate constant, i.e., [1/T IS ϭ 1/T 1 * -1/T 1 ], where T 1 and T 1 * are the longitudinal magnetizations of the observed water protons before and after irradiation of the saturation transfer pulse on polymer protons, respectively (13,14). We further refined this technique and showed that the cross-relaxation rate can be calculated using a simple equation (15,16). We named this technique "equivalent cross-relaxation rate imaging" (ECRI). We suggested that the equivalent cross-relaxation rate (ECR) at frequency offsets below 10 ppm depends not only on the rigidity of gels, bu...

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