OPTICAL DESIGN AND BREADBOARD OF THE RAMAN SPECTROMETER FOR MMX

This paper reports the laboratory confirmation of an optical design for a 0.2 numerical aperture confocal miniaturized, ruggedized Raman visible light spectroscope (RAX) to be borne by an autonomous rover landed on the martian moon, Phobos

Focal dose escalation using FDG-PET-guided intensity-modulated radiation therapy boost for postoperative local recurrent rectal cancer: a planning study with comparison of DVH and NTCP

<p>Abstract</p> <p>Background</p> <p>To evaluate the safety of focal dose escalation to regions with standardized uptake value (SUV) >2.0 using intensity-modulated radiation therapy (IMRT) by comparison of radiotherapy plans using dose-volume histograms (DVHs) and normal tissue complication probability (NTCP) for postoperative local recurrent rectal cancer</p> <p>Methods</p> <p>First, we performed conventional radiotherapy with 40 Gy/20 fr. (CRT 40 Gy) for 12 patients with postoperative local recurrent rectal cancer, and then we performed FDG-PET/CT radiotherapy planning for those patients. We defined the regions with SUV > 2.0 as biological target volume (BTV) and made three boost plans for each patient: 1) CRT boost plan, 2) IMRT without dose-painting boost plan, and 3) IMRT with dose-painting boost plan. The total boost dose was 20 Gy. In IMRT with dose-painting boost plan, we increased the dose for BTV+5 mm by 30% of the prescribed dose. We added CRT boost plan to CRT 40 Gy (<it>summed plan 1</it>), IMRT without dose-painting boost plan to CRT 40 Gy (<it>summed plan 2</it>) and IMRT with dose-painting boost plan to CRT 40 Gy (<it>summed plan 3</it>), and we compared those plans using DVHs and NTCP.</p> <p>Results</p> <p>D_meanof PTV-PET and that of PTV-CT were 26.5 Gy and 21.3 Gy, respectively. V₅₀of small bowel PRV in <it>summed plan 1 </it>was significantly higher than those in other plans ((<it>summed plan 1 </it>vs. <it>summed plan 2 </it>vs. <it>summed plan 3</it>: 47.11 ± 45.33 cm³vs. 40.63 ± 39.13 cm³vs. 41.25 ± 39.96 cm³(p < 0.01, respectively)). There were no significant differences in V₃₀, V₄₀, V₆₀, D_meanor NTCP of small bowel PRV.</p> <p>Conclusions</p> <p>FDG-PET-guided IMRT can facilitate focal dose-escalation to regions with SUV above 2.0 for postoperative local recurrent rectal cancer.</p

Attentional Set-Shifting Deficit in Parkinson’s Disease Is Associated with Prefrontal Dysfunction: An FDG-PET Study

The attentional set-shifting deficit that has been observed in Parkinson’s disease (PD) has long been considered neuropsychological evidence of the involvement of meso-prefrontal and prefrontal-striatal circuits in cognitive flexibility. However, recent studies have suggested that non-dopaminergic, posterior cortical pathologies may also contribute to this deficit. Although several neuroimaging studies have addressed this issue, the results of these studies were confounded by the use of tasks that required other cognitive processes in addition to set-shifting, such as rule learning and working memory. In this study, we attempted to identify the neural correlates of the attentional set-shifting deficit in PD using a compound letter task and 18F-fluoro-deoxy-glucose (FDG) positron emission tomography during rest. Shift cost, which is a measure of attentional set-shifting ability, was significantly correlated with hypometabolism in the right dorsolateral prefrontal cortex, including the putative human frontal eye field. Our results provide direct evidence that dysfunction in the dorsolateral prefrontal cortex makes a primary contribution to the attentional set-shifting deficit that has been observed in PD patients

In situ science on Phobos with the Raman spectrometer for MMX (RAX): preliminary design and feasibility of Raman meausrements

Mineralogy is the key to understanding the origin of Phobos and its position in the evolution of the Solar System. In situ Raman spectroscopy on Phobos is an important tool to achieve the scientifc objectives of the Martian Moons eXploration (MMX) mission, and maximize the scientifc merit of the sample return by characterizing the mineral composition and heterogeneity of the surface of Phobos. Conducting in situ Raman spectroscopy in the harsh environment of Phobos requires a very sensitive, compact, lightweight, and robust instrument that can be carried by the compact MMX rover. In this context, the Raman spectrometer for MMX (i.e., RAX) is currently under development via international collaboration between teams from Japan, Germany, and Spain. To demonstrate the capability of a compact Raman system such as RAX, we built an instrument that reproduces the optical performance of the fight model using commercial of-the-shelf parts. Using this performance model, we measured mineral samples relevant to Phobos and Mars, such as anhydrous silicates, carbonates, and hydrous minerals. Our measurements indicate that such minerals can be accurately identifed using a RAX-like Raman spectrometer. We demonstrated a spectral resolution of approximately 10 cm−1, high enough to resolve the strongest olivine Raman bands at ~820 and ~850 cm−1, with highly sensitive Raman peak measurements (e.g., signal-to-noise ratios up to 100). These results strongly suggest that the RAX instrument will be capable of determining the minerals expected on the surface of Phobos, adding valuable information to address the question of the moon’s origin, heterogeneity, and circum-Mars material transport

Mouse model of lymph node metastasis via afferent lymphatic vessels for development of imaging modalities.

Animal studies of lymph node metastasis are constrained by limitations in the techniques available for noninvasive monitoring of the progression of lymph node metastasis, as well as difficulties in the establishment of appropriate animal models. To overcome these challenges, this study has developed a mouse model of inter-lymph-node metastasis via afferent lymphatic vessels for use in the development of imaging modalities. We used 14- to 18-week-old MRL/MpJ-/lpr/lpr (MRL/lpr) mice exhibiting remarkable systemic lymphadenopathy, with proper axillary lymph nodes (proper-ALNs) and subiliac lymph nodes (SiLNs) that are 6 to 12 mm in diameter (similar in size to human lymph nodes). When KM-Luc/GFP malignant fibrous histiocytoma-like cells stably expressing the firefly luciferase gene were injected into the SiLN, metastasis could be detected in the proper-ALN within 3 to 9 days, using in vivo bioluminescence imaging. The metastasis route was found to be via the efferent lymphatic vessels of the SiLN, and metastasis incidence depended on the number of cells injected, the injection duration and the SiLN volume. Three-dimensional contrast-enhanced high-frequency ultrasound imaging showed that the blood vessel volume and density in the metastasized proper-ALN significantly increased at 14 days after tumor cell inoculation into the SiLN. The present metastasis model, with lymph nodes similar in size to those of humans, has potential use in the development of ultrasound imaging with high-precision and high-sensitivity as well as other imaging modalities for the detection of blood vessels in lymph nodes during the progression of metastasis

Parameters related to the incidence of metastasis.

<p>A. Effects of inoculation conditions on the incidence of lymph node metastasis. Metastatic incidence increased with injection of a larger number cells (a), did not vary significantly with injection duration (b), but decreased with a larger SiLN volume (c). In the values presented above the bars, the denominator represents the number of inoculated mice while the numerator represents the number of mice with metastases in the proper-ALN. NS indicates P>0.05; *P<0.05 calculated by Fisher’s exact probability test. B. Assessment of the correlation between the above 3 parameters and metastasis incidence, using a new parameter, cells mm⁻³ min⁻¹. When metastasis incidence was set at 1, 100% metastasis was achieved when the cells mm⁻³ min⁻¹ value exceeded 4.72×10² (n = 39). Analyses were performed with the Mann-Whitney U test.</p

Monitoring of metastatic progression by CE-HFUS with Als.

<p>A. Imaging of the temporal changes in angiogenic vessel density in a cross-section of a metastatic proper-ALN, visualized by CE-HFUS with ALs. Blood vessel density increased with tumor progression. Red circles indicate the proper-ALN boundary, arrows and dotted lines indicate the AL-enhanced region, and green highlighting indicates the dense area of neovasculature in the proper-ALN. B. Results of 3D quantitative analysis of the temporal changes in blood vessel volume and density in metastatic proper-ALNs. The term “cells” indicates the metastasized group (1×10⁵ cells/min, <i>n</i> = 4) and “PBS” the negative control group (<i>n</i> = 3). Values for each group were normalized against the measurement on day 0. Error bars indicate the SEM values. * is for comparison of the temporal change within each group; # is for comparison between groups. * or #, <i>P</i><0.05; ** or ##, <i>P</i><0.01, calculated using two-way ANOVA followed by the Tukey-Kramer test.</p

Establishment of the model of lymph node metastasis.

<p>A. Representative images captured by <i>in vivo</i> bioluminescence imaging of a mouse with tumor cells grafted into the SiLN to promote metastasis to the ALN. (<i>a</i>) <i>In vivo</i> and (<i>b</i>) <i>ex vivo</i> bioluminescence signals in the proper-ALN and SiLN on day 14 post-inoculation, indicating that the proper-ALN is the draining lymph node. B. Graph showing the high correlation between <i>in vivo</i> and <i>ex vivo</i> bioluminescence (<i>P</i> = 0.0023; Spearman’s rank correlation coefficient [rs]  = 0.9161; SiLN, <i>n</i> = 6; proper-ALN, <i>n</i> = 6). C. Results of histological verification. Tumor cells stained with H&E and luciferase-positive immunohistochemical signals in the proper-ALN and SiLN. MS: marginal sinus. T: tumor. D. Dissemination of KM-Luc/GFP cells (metastasis, <i>n = </i>4) or PBS alone (control, <i>n = </i>3) to each organ, assessed on day 14 post-injection of the SiLN. I, ipsilateral; C, contralateral; LN, lymph node. Error bars indicate the SEM values.</p

Metastatic flow and route. A.

<p>ICG flow from the SiLN to the proper-ALN, observed using an <i>in vivo</i> fluorescence imaging system (IVIS; <i>n</i> = 1). <b>B.</b> Representative PDE images, following an ICG injection speed of 0.5 mL/h. The speed of ICG flow was calculated by dividing the distance, <i>l</i>, by the duration of time that had elapsed post-injection. <b>C.</b> Graph of the relationship between ICG flow speed and intra-SiLN injection speed (low, 0.5; medium, 1.0; high, 3.0 mL/h; <i>n</i> = 4 per group), revealing a low level of variation between individual experiments in the low-speed group. D. HS-FVCS image of the afferent lymphatic vessels after intra-SiLN injection of FITC-BSA solution (<i>n</i> = 2). (<i>a</i>) Area near the SiLN and proper-ALN captured by a normal digital camera. Two regions of interest were selected. (<i>b</i>) Bright field images obtained by HS-FVCS, without use of a fluorescence filter. A thick superficial epigastric vein (→) was observed. (<i>c</i>) Fluorescence images obtained by HS-FVCS, with use of an appropriate fluorescence filter (bandwidth: 510±2 nm). A new flow channel filled with FITC-BSA solution (→) appeared at a distance of about 200 µm from the vein. (<i>d</i>) Results of hematoxylin and eosin (H&E) staining. The flow channel was identified as the afferent lymphatic vessels by injection of Indian ink. The vein was not stained (<i>n</i> = 1).</p