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Katsuhiko Shimizu,1 Masao Nakata,1 Shinsuke Saisho,1 Masayuki Inubushi,2 Norihito Okumura,3 Tomohiro Murakawa,4 Motohiro Yamashita,5 Hiroshige Nakamura,6 Yoshifumi Sano,7 Kazuhiko Kataoka,8 Shinichi Toyooka9 1Department of General Thoracic Surgery, Kawasaki Medical School, Kurashiki, Japan; 2Division of Nuclear Medicine, Department of Radiology, Kawasaki Medical School, Kurashiki, Japan; 3Department of Thoracic Surgery, Kurashiki Central Hospital, Kurashiki, Japan; 4Department of Thoracic Surgery, Kansai Medical University, Osaka, Japan; 5Department of Thoracic Surgery, Shikoku Cancer Center, Matsuyama, Japan; 6Division of General Thoracic Surgery, Tottori University Hospital, Yonago, Japan; 7Department of Cardiovascular and Thoracic Surgery, Ehime University Graduate School of Medicine, Toon, Japan; 8Department of Thoracic Surgery, National Hospital Organization Iwakuni Clinical Center, Iwakuni, Japan; 9Department of General Thoracic Surgery and Breast and Endocrinological Surgery, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, JapanCorrespondence: Katsuhiko Shimizu, Department of General Thoracic Surgery, Kawasaki Medical School, 577 Matsushima, Kurashiki, Okayama, 701-0192, Japan, Tel +81-86-462-1124, Fax +81-86-464-1124, Email kshimizu@med.kawasaki-m.ac.jpBackground: Induction therapy followed by surgery is recommended as an alternative treatment strategy for locally advanced non-small cell lung cancer (NSCLC). Patients who achieve pathologic response after induction therapy have better outcomes than non-responders; therefore, therapeutic response must be evaluated. Recently, new approaches for monitoring therapeutic responses, which are based on 18F‐Fluorodeoxyglucose positron emission tomography (FDG‐PET), have been developed. In this study, we evaluated the predictive value of Positron Emission Tomography Response Criteria in Solid Tumors (PERCIST), which uses standardized uptake values corrected for lean body mass (SUL) and total lesion glycolysis (TLG).Methods: A total of 130 patients in the Setouchi Lung Cancer Group who underwent FDG-PET imaging before and after induction therapy prior to a planned surgical resection for NSCLC between 2007 and 2016 were studied retrospectively. The pathologic responses of the primary lung tumors and metastatic lymph nodes were compared with their responses based on evaluation using PERCIST.Results: Postoperative pathologic studies revealed pathologic complete response (pCR) in 42 (32.3%) patients. PERCIST was significantly correlated with pathologic response (p < 0.001). The sensitivity, specificity, and accuracy of PERCIST for predicting pCR were 16.7% (7/42), 88.6% (78/88), and 65.4% (85/130), respectively. Patients with pCR had significantly higher reduction rates in SULpeak for both primary lung tumors and metastatic lymph nodes and TLG for primary tumors than non-responders. In a multivariate Cox regression analysis, tumor site in upper lobes, reduction rate of TLG in primary tumor, and pathologic N0 were independent predictors of favorable recurrence-free survival (RFS).Conclusion: Our study suggested that PERCIST, especially the rate of TLG reduction rate, are useful to predict the pathological response and prognosis after induction therapy. Although improvement is necessary, PERCIST can be a promising method of the post-induction status in lung cancer. Further research is needed to confirm our findings.Keywords: non-small cell lung cancer, FDG PET, PERCIST, SUL, TLG

Objective: The purpose of this prospective study was to assess the prognostic value of 3'-deoxy-3'-[(18)F]fluorothymidine (FLT) positron emission tomography/computed tomography (PET/CT) for the outcome of carbon ion radiotherapy (CIRT) in patients with mucosal malignant melanoma (MMM) of the head and neck. Methods: Thirteen patients (69 ± 13 years) with histologically proven MMM tumor were enrolled. CIRT was performed with a total dose of 57.6-64.0 gray equivalents per 16 fractions over a period of 4 weeks. FLT-PET/CT was performed before and again 1 month after CIRT. Tumor FLT uptake was quantitatively assessed using the maximum standardized uptake value (SUV(max)). FLT-PET parameters [pre-CIRT SUV(max), post-CIRT SUV(max), and the reduction rate (RR)] and clinical parameters [age, gender, tumor site, tumor status, gross tumor volume (GTV), and regional lymph node involvement] were evaluated in relation to survival estimates. The follow-up period was 16.1 ± 5.9 months for 9 deceased patients, and 36.7 ± 7.9 months for 4 survivors. Results: Pre-CIRT SUV(max) of ≥4.3, age of ≥80 years old, sinonasal cavity tumor site, and GTV of ≥39 mL were found to be statistically significant prognostic factors for better overall survival. Pre-CIRT SUV(max) of ≥5.0, age of ≥80 years old, sinonasal cavity tumor site, and the absence of regional lymph node involvement were statistically significant prognostic factors for better metastasis-free survival. RR of ≥35 % and GTV of <73 mL were predictive of better local control. Conclusions: The present study indicated for the first time that in patients with the head and neck MMM, FLT-PET/CT imaging was useful for predicting the therapeutic outcome of CIRT. Our results will contribute to the establishment of an effective staging system for MMM based on prognostic factors, depending on treatment choice. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to investigate whether improvement of regional inflammatory findings in knee joints of rheumatoid arthritis (RA) could be detected by positron-emission tomography (PET) using (18)F-Fluorodeoxyglucose (FDG) after acupuncture treatments, as well as improvement of systemic inflammatory markers. Methods: Six RA patients (all female, 61 +/- 12 years old) received 10 acupuncture treatments in 2 months, to 11 traditional acupuncture points around a knee joint considered effective on RA. A visual analogue scale (VAS) for intensity of pain, knee joint range of motion (ROM), face scale for patient mood, and modified health assessment questionnaire (MHAQ) for disability of daily activities were assessed just before and after acupuncture. Maximum standardized uptake value (SUV(max)) and the volume with SUV more than 1.0 [Volume(SUV > 1)] on FDG-PET images as well as erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels were also measured before and after the treatments. Results: VAS, ROM, face scale and MHAQ improved in all patients and significantly after acupuncture, but no significant change was detected in ESR, CRP, SUV(max), or Volume(SUV > 1). Conclusions: Acupuncture relieves symptom, remedies physical function, and improves quality of life in RA patients, but may have no or very limited anti-inflammatory effect systemically. The regional effects of acupuncture are unlikely to be induced through reduction of regional inflammation. We believe this clinical study is the first step for elucidating therapeutic mechanisms of acupuncture, which must be important for the rational use and further development of acupuncture. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the diagnostic accuracy of fluorodeoxyglucose positron emission tomography (FDG-PET) relative to computed tomography (CT) for detecting metastatic cervical lymph nodes in patients with squamous cell carcinoma of the head and neck (HNSCC), and to ascertain the factors that affect this accuracy. Methods: A total of 1076 lymph nodes obtained from 35 neck dissections in 26 HNSCC patients who preoperatively underwent both FDG-PET and CT were retrospectively analyzed. For pathological metastatic lymph nodes, the lymph node size (short-axis diameter), the ratio of intranodal tumor deposits, and the size of intranodal tumor deposits (maximum diameter of metastatic foci in each lymph node) were histologically recorded. Results: Forty-six lymph nodes from 23 neck sides were pathologically diagnosed metastases. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of FDG-PET evaluated individually per neck side were 74%, 92%, 80%, 94%, and 65%, respectively, whereas those of CT were 78%, 58%, 71%, 78%, and 58%, respectively. FDG-PET detected 100% of metastatic lymph nodes > or =10 mm, intranodal tumor deposits > or =9 mm, and intranodal tumor deposits with a ratio >75%, whereas no nodes or tumor deposits smaller than 5 mm were detected. The spatial resolution limitations of FDG-PET were responsible for 16 of 20 (80%) false-negative PET results in lymph nodes. Conclusions: FDG-PET is a useful tool for preoperative evaluation of the neck because it accurately detects metastatic lymph nodes > or =10 mm and has fewer false-positive cases than CT. The high specificity of FDG-PET for lymph node metastases may play an important role in avoiding unnecessary neck dissection. [ABSTRACT FROM AUTHOR]

Aims The mechanism by which enhanced external counterpulsation therapy exerts its beneficial effects on chronic and symptomatic stable angina is largely unknown. To clarify the mechanism of action of enhanced external counterpulsation, we used13N-ammonia positron emission tomography to evaluate myocardial perfusion.Methods and Results This was not a randomized controlled study. Eleven patients (eight male, age: 61·6±9·7) with angina pectoris underwent enhanced external counterpulsation therapy for 35 1h sessions. They underwent a treadmill exercise test and13N-ammonia positron emission tomography, both at rest and with dipyridamole, before and after enhanced external counterpulsation therapy. Neurohumoral factors and nitric oxide were also evaluated. Myocardial perfusion increased at rest after therapy (0·69±0·27 to 0·85±0·47ml.min−1.g−1,P <0·05). In ischaemic regions, particularly the anterior region, myocardial perfusion at rest and with dipyridamole and coronary flow reserve improved significantly after therapy (at rest: 0·71±0·26 to 0·86±0·31;P<0·05, with dipyridamole: 1·26±0·65 to 1·84±0·94;P<0·02, coronary flow reserve: 1·75±0·24 to 2·08±0·28;P<0·04). Exercise time was prolonged and the time to 1-mm ST depression improved markedly (P<0·01). After therapy, nitric oxide levels increased (P<0·02) and neurohumoral factors decreased.Conclusions Enhanced external counterpulsation therapy improved myocardial perfusion at rest and with dipyridamole and was associated with an increased exercise tolerance with13N-ammonia positron emission tomography and increased nitric oxide levels. These results suggest that one of the enhanced external counterpulsation mechanisms is development and recruitment of collateral vessels. [ABSTRACT FROM PUBLISHER]

Purpose: This study aimed to evaluate a novel technique for cell tracking by visualising the activity of the human sodium/iodide symporter (hNIS) after transplantation of hNIS-expressing multilayered cell sheets in a rat model of chronic myocardial infarction., Methods: Triple-layered cell sheets were generated from mouse embryonic fibroblasts (MEFs) derived from mice overexpressing hNIS (hNIS-Tg). Myocardial infarction was induced by permanent ligation of the left anterior descending coronary artery in F344 athymic rats, and a triple-layered MEFs sheets were transplanted to the infarcted area two weeks after surgery. To validate the temporal tracking and kinetic analysis of the transplanted MEFs sheets, sequential cardiac single-photon emission computed tomography (SPECT) examinations with a 99m TcO 4 - injection were performed. The cell sheets generated using MEFs of wild-type mice (WT) served as controls., Results: A significantly higher amount of 99m TcO 4 - was taken into the hNIS-Tg MEFs than into WT MEFs (146.1 ± 30.9-fold). The obvious accumulation of 99m TcO 4 - was observed in agreement with the region where hNIS-Tg MEFs were transplanted, and these radioactivities peaked 40-60 min after 99m TcO 4 - administration. The volume of distribution of the hNIS-Tg MEF sheets declined gradually after transplantation, implying cellular malfunction and a loss in the number of transplanted cells., Conclusion: The reporter gene imaging with hNIS enables the serial tracking and quantitative kinetic analysis of cell sheets transplanted to infarcted hearts., (© 2024. The Author(s).)

In vitro studies using cell culture, including three-dimensional cultures without the involvement of tumor vessels, have limitations in simulating complex intratumoral hypoxic conditions in live subjects. To generate experimental hypoxic conditions closer to those observed in humans in clinical settings, in vivo studies are necessary. In addition, visible light generated via bioluminescence and fluorescence is generally unsuitable for in vivo experiments because of low tissue penetration. Furthermore, near-infrared light (NIR), which has the highest tissue penetration among lights of different wavelengths, cannot be assessed precisely in vivo because of the difficulty in correcting tissue absorption and scatter. For in vivo quantitative analyses, imaging modalities that use high tissue-penetrating signals, such as computed tomography (CT) using X-rays, radionuclide imaging using γ-rays, and magnetic resonance imaging (MRI) using electromagnetic waves, are ideal.Therefore, as an advanced protocol for this research purpose, we provide ex vivo and in vivo methods to investigate the genetic response of multiple copies of hypoxia response elements (HREs) to tumor hypoxia in terms of intensity and intratumoral distribution using a human sodium/iodide symporter (hNIS) reporter gene and radionuclide reporter probes (radioiodine and its chemical analog Tc-99m) based on our previous research. This protocol includes cloning an hNIS reporter construct with multiple copies of HREs, establishing stable cell lines of the reporter construct, preparing a mouse subcutaneous xenograft model, and evaluating the genetic response of multiple HREs to tumor hypoxia using digital autoradiography (ARG) ex vivo and using single-photon emission computed tomography (SPECT) or positron emission tomography (PET) in vivo., (© 2024. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Hypoxia is a hallmark of ischemic cardiovascular diseases and solid malignant tumors. Cellular hypoxia induces numerous physiological and pathological processes, including hematopoiesis, angiogenesis, metabolic changes, cell growth, and apoptosis. Hypoxia-inducible factor-1 (HIF-1) binds to hypoxia response elements (HREs) to selectively induce the expression of various genes in response to hypoxia. Therefore, HREs have been used to develop hypoxia-targeted gene therapy.More than 70 pairs of HREs and hypoxia-inducible genes have been identified. The hypoxia-induced gene expression levels vary among HRE sequences depending on the number of HRE copies and oxygen levels. Most known HREs have not yet been thoroughly studied. Recent studies have revealed that the HRE-mediated effects of hypoxia are cell line-dependent. Herein we describe an in vitro method to investigate gene activation levels and characteristics based on varying the copy number of HREs in response to cellular hypoxia. We explain how to clone HREs into luciferase reporter constructs in the sense, antisense, and dual directions to measure luciferase expression for functional analyses., (© 2024. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Data assimilation (DA) of turbulence, which involves reconstructing small-scale turbulent structures based on observational data from large-scale ones, is crucial not only for practical forecasting but also for gaining a deeper understanding of turbulent dynamics. We propose a theoretical framework for DA of turbulence based on the transverse Lyapunov exponents (TLEs) in synchronization theory. Through stability analysis using TLEs, we identify a critical length scale as a key condition for DA; turbulent dynamics smaller than this scale are synchronized with larger-scale turbulent dynamics. Furthermore, considering recent findings for the maximal Lyapunov exponent and its relation with the TLEs, we clarify the Reynolds number dependence of the critical length scale.

Purpose: The purpose of this study was to evaluate the residual radioactivity in the syringe and route of administration of a low fluid volume 99m Tc-macro aggregated albumin (MAA) intended for pediatric nuclear medicine examinations., Method: We evaluated the residual characteristics, as the effect of elapsed time from drawing up of radiopharmaceuticals to plastic syringe to administration, and the effect of volume of 99m TcO 4 - solution to be labeled, the effect of rinsed times of plastic syringe, effect of dose of calculated by consensus guidelines for pediatric nuclear medicine and residual location in injection sets with 99m Tc-MAA. Residual radioactivity was measured using planar images obtained by the gamma camera., Results: Residual radioactivity rate of 99m Tc-MAA, 99m Tc-MAG 3 , 123 I-IMP showed 41.3±1.6%, 14.4±0.6%, 14.6±2.0%, respectively. 99m Tc-MAA clearly showed a higher residual rate. Residual radioactivity rate increased with the extension of the elapsed time, and reached a high value of 41.3% in 30 minutes. Residual radioactivity rate was dependent on the different volume of 99m TcO 4 - to be labeled (4.0 ml and 8.0 ml). Residual radioactivity rate did not change when the number of rinsed was more than one. Residual rate was around 40% at all doses of calculated by consensus guidelines for pediatric nuclear medicine., Conclusion: 99m Tc-MAA showed the highest residual radioactivity rate among radiopharmaceuticals used in pediatric nuclear medicine examinations. The factor that most affected the residual radioactivity rate of 99m Tc-MAA was the elapsed time from draw up to the plastic syringe to administration.

Background/aim: To evaluate the Spinal Instability Neoplastic Score (SINS) for prediction of survival in patients with spinal column metastasis of castration-resistant prostate cancer (CRPC)., Patients and Methods: A retrospective study of spinal instability was performed in patients with CRPC using SINS. Overall survival was evaluated starting from the time of SINS evaluation. The subjects were 42 patients with CRPC among 261 cases diagnosed with metastatic spinal tumors by radiologists, among 42,152 cases that underwent a body computed tomography scan at Kawasaki Medical School Hospital within 32 months from December 2013 to July 2016., Results: The median age was 78 (range=55-91 years), the median prostate-specific antigen (PSA) level at SINS evaluation was 42.1 (0.1-3,121.6) ng/ml, and 11 patients had visceral metastasis. The median periods from diagnosis of bone metastasis and development of CRPC to SINS evaluation were 17 (0-158) and 20 (0-149) months, respectively. The spine was stable in 32 cases (group S) and potentially unstable or unstable in 10 (24%) (group U). The median observation period was 17.5 (0-83) months and 36 patients died. The median survival period after SINS evaluation was longer in group S than that in group U (20 vs. 10 months, p=0.0221). In multivariate analysis, PSA level, visceral metastasis, and spinal instability were significant prognostic factors. The hazard ratio for patients in group U was 2.60 (95%CI=1.07-5.93, p=0.0345)., Conclusion: Spinal stability evaluated using SINS is a new prognostic factor for survival of patients with spinal metastasis of CRPC., Competing Interests: The Authors have no conflicts of interest to declare in relation to this study., (Copyright 2023, International Institute of Anticancer Research.)

Fluid mixing is crucial in various industrial processes. In this study, focusing on the characteristics that reinforcement learning (RL) is suitable for global-in-time optimization, we propose utilizing RL for fluid mixing optimization of passive scalar fields. For the two-dimensional fluid mixing problem described by the advection-diffusion equations, a trained mixer realizes an exponentially fast mixing without any prior knowledge. The stretching and folding by the trained mixer around stagnation points are essential in the optimal mixing process. Furthermore, this study introduces a physically reasonable transfer learning method of the trained mixer: reusing a mixer trained at a certain Péclet number to the mixing problem at another Péclet number. Based on the optimization results of the laminar mixing, we discuss applications of the proposed method to industrial mixing problems, including turbulent mixing., (© 2022. The Author(s).)

Restricted lower limb vasculitis is a type of localized muscle vasculitis limited to the lower limbs. The usefulness of fluorodeoxyglucose-positron emission tomography (FDG-PET) for the diagnosis of this entity has not yet been reported. We herein report three patients with a fever and persistent lower limb pain. FDG-PET revealed linear and patchy FDG uptakes in their lower limbs. Combined with magnetic resonance imaging and histological findings, they were diagnosed with lower limb vasculitis. Linear and patchy FDG uptakes are considered to reflect the presence of muscle vasculitis. The characteristic "ant-farm"-like FDG-PET images can be a diagnostic clue for the currently overlooked vasculitis.

Purpose: The purpose of the study was to invent and evaluate the novel artificial intelligence (AI) system named Fertility image Testing Through Embryo (FiTTE) for predicting blastocyst viability and visualizing the explanations via gradient-based localization., Methods: The authors retrospectively analyzed 19 342 static blastocyst images with related inspection histories from 9961 infertile patients who underwent in vitro fertilization. Among these data, 17 984 cycles of single-blastocyst transfer were used for training, and data from 1358 cycles were used for testing purposes., Results: The prediction accuracy for clinical pregnancy achieved by a control model using conventional Gardner scoring system was 59.8%, and area under the curve (AUC) was 0.62. FiTTE improved the prediction accuracy by using blastocyst images to 62.7% and AUC of 0.68. Additionally, the accuracy achieved by an ensemble model using image plus clinical data was 65.2% and AUC was 0.71, representing an improvement in prediction accuracy. The visualization algorithm showed brighter colors with blastocysts that resulted in clinical pregnancy., Conclusions: The authors invented the novel AI system, FiTTE, which could provide more precise prediction of the probability of clinical pregnancy using blastocyst images secondary to single embryo transfer than the conventional Gardner scoring assessments. FiTTE could also provide explanation of AI prediction using colored blastocyst images., Competing Interests: This study was funded in part by the Kobe Medical Industry Development Project, which is a public grant providing support in the form of research materials. The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. Isao Miyatsuka and Le My An are employees of NextGem Inc. The equipment and programs have been jointly provided by NextGem Inc., (© 2022 The Authors. Reproductive Medicine and Biology published by John Wiley & Sons Australia, Ltd on behalf of Japan Society for Reproductive Medicine.)

Prostate-specific membrane antigen (PSMA) is a transmembrane glycoprotein highly expressed by prostate cancer cells. PSMA-based radioligand therapy (RLT) emerged as a promising therapeutic option for prostate cancer in the early 2000s, and has been clinically validated with great enthusiasm during these past two decades. Last year, the European Association of Nuclear Medicine (EANM) published the procedure guidelines for the safe clinical practice of Lutetium-177 ( 177 Lu)-labelled PSMA RLT. In addition, PSMA RLT with alpha-ray-emitting radioisotopes has been also developed recently. Following the clinical use of 177 Lu-PSMA RLT, PSMA-targeted positron-emission tomography (PET) with Gallium-68 ( 68 Ga) has been performed inevitably for "theranostics" for the last decade; prostate cancer is going to be treated with PSMA-RLT based on the diagnosis by PSMA-PET. Furthermore, the diagnostic usefulness of 68 Ga-PSMA PET has been documented in various diseases beyond prostate cancer more recently. Regrettably, Japan is behind European countries and the United States in this field, and has just made a belated start of their clinical trials. In this review article, we briefly overviewed the current status of PSMA RLT and PSMA PET. We hope that this topic will be a particular focus of attention for most ANM readers in Japan, and that our efforts will help to facilitate the early approval of PSMA RLT and PSMA PET by the Japanese government even if only slightly.

We introduce transfer learning for nonlinear dynamics, which enables efficient predictions of chaotic dynamics by utilizing a small amount of data. For the Lorenz chaos, by optimizing the transfer rate, we accomplish more accurate inference than the conventional method by an order of magnitude. Moreover, a surprisingly small amount of learning is enough to infer the energy dissipation rate of the Navier-Stokes turbulence because we can, thanks to the small-scale universality of turbulence, transfer a large amount of the knowledge learned from turbulence data at lower Reynolds number.

We investigated the usefulness of diffusion-weighted imaging (DWI) for detecting changes in the structure of hypoxic cells by evaluating the correlation between 18 F-fluoroazomycin arabinoside (FAZA) positron emission tomography activity and DWI parameters in head and neck carcinoma. The diffusion coefficient corresponding to the slow compartment of a two-compartment model had a significant positive correlation with FAZA activity (ρ = 0.58, P = 0.016), whereas the diffusional kurtosis from diffusion kurtosis imaging had a significant negative correlation (ρ = -0.62, P = 0.008), which suggests that those DWI parameters might be useful as indicators for changes in cell structure.

We can judge affective aspects of objects by actively exploring them with our hands. Previous studies have mainly focused on how the physical properties of an object's surface affect tactile preference evaluations. However, despite the widely accepted notion that the participant's strategy has a great impact on how they explore an object, there is a lack of investigations of hand motion during preference judgment and its impact on preference rating. This paper recruits the recurrence plot technique to illustrate the temporal dynamics of explorative hand motion. In an experiment, participants were asked to freely explore the surface of tactile stimuli and rate their tactile preference for them. The temporal dynamics of finger velocity and force were visualized and characterized by using recurrence quantification analysis. We found correlations between preference ratings and recurrence features that represent the temporal dynamics of explorative hand motion, in addition to correlations between preference ratings and conventional time-averaged features (e.g., averaged finger velocity). One unique feature that correlated with preference ratings was TREND, which represents to what extent similar motion patterns repeatedly occur. The results of a subsidiary analysis supported the possibility that the TREND difference can be interpreted as the frequency of switching touching modes (e.g., stroking and pushing motions). Taken together, these results suggest that participants tend to perform the same hand motion repeatedly for preferable objects, while they tend to combine different touching modes for less preferable objects. They also indicate that the recurrence plot scheme is a promising way to extract humans' strategies for tactile exploration.

Although it may not be well known, the Annals of Nuclear Medicine (ANM) Editorial Committee includes one specialty editor of nuclear medicine physics, one of nuclear medicine technology, one of molecular imaging, and two of radiopharmacology. In addition, a statistics editor and a language editor are also on the committee. Manuscripts submitted to ANM can be peer-reviewed by such specialty editors similar to those submitted to highly ranked journals, which is a great pride and joy to us. To offer our readers a condensed global view on the high-quality research work in the field of nuclear medicine, we have published a mini-review article every year under the joint authorship of the ANM associate editors since 2016. This is our fourth serial review article written by the ANM specialty editors from their respective expert viewpoints.

Objective: Patients often take prescription drugs for various diseases or complications that contain several grams of glucose. However, the effect of these glucose-containing medications on the image quality of F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) has not been established. This study aimed to evaluate the effect of taking drugs containing glucose before an FDG-PET on the PET image quality., Methods: In total, 736 continuously enrolled patients who underwent FDG-PET were retrospectively analysed. We investigated the total glucose content in the prescription drugs that each patient took during fasting before the FDG injection, and we divided the patients into three groups according to the amount of glucose in their drugs: group A did not take any drugs containing glucose, group B took sugar-coated tablets (containing trace amounts of glucose), and group C took prescription drugs with glucose an ingredient. Visual scores and quantitative variables with standard uptake value (SUV) for the brain, myocardium, blood, liver, and muscle in the FDG-PET images were analysed and statistically compared across the three groups., Results: In group C, the amount of glucose was 0.63 ± 0.86 g (maximum 4.9 g). For the visual scores, there were no significant differences among the three groups. For the quantitative variables, significant differences were present in the brain SUVmax, muscle SUVmean, brain/blood ratio, brain/liver ratio, and brain/muscle ratio. However, a multivariate analysis showed that the group indicator was not significantly associated with any of the quantitative variables. On the other hand, blood glucose was significantly associated with the visual and quantitative variables. In group C, the correlation coefficient between the amount of glucose and the blood glucose level, the visual scores and the quantitative variables were in the range of - 0.121 to 0.100 and were not significant., Conclusions: There were no significant differences between glucose-containing medications before FDG-PET and the visual scores and quantitative variables for FDG-PET image. Several grams of glucose in drugs before FDG-PET can be ignored.

Random number generation is a fundamental technology behind information security. Recently, physical random number generators (RNGs), which especially harness optical chaos such as in delay-feedback lasers, have been studied intensively. Although these are promising technologies for future information security, there is little theoretical foundation. In this paper, we newly introduce a mathematical formulation of physical RNGs based on a model of chaotic dynamics and give the first rigorous results. In particular, by combining ergodic theory, information theory, and response theory of statistical physics, our theory guarantees, for the model of chaotic dynamics, the coexistence of two crucial properties necessary for physical RNGs: fast random number generation and robustness. Compared with other types of physical RNGs, our theoretical findings highlight an unnoticed advantage of chaotic dynamics utilized for physical RNGs.

Written by associate editors of the Annals of Nuclear Medicine, this invited review article is intended to offer our readers a condensed global view on the high-quality research work that has been published in Europe last year. We have divided this article into five sections. The first three sections from the oncology category include "[ 18 F]fluorodeoxyglucose (FDG) positron-emission tomography (PET) for therapy monitoring in malignant lymphoma", "[ 18 F]fluoromisonidazole (FMISO) PET for hypoxia", and "lymphoscintigraphy update". It is followed by a section on "amyloid PET for Alzheimer's disease" using [ 11 C]Pittsburgh Compound B (PiB) and [ 18 F]florbetapir from the neurology category. The final section reviews three original articles in the field of "basic and translational molecular imaging" regardless of the category, which investigated new PET tracers such as L-4-borono-2-[ 18 F]fluoro-phenylalanine (FBPA), O-(2-[ 18 F]fluoroethyl)-L-tyrosine (FET) and 64 Cu-NOTA-pertuzumab in small animals. We hope that this review article will arouse greater interest in our readers in recent European research trends in the field of nuclear medicine.

Photonic reservoir computing is a new paradigm for performing high-speed prediction and classification tasks in an efficient manner. The major challenge for the miniaturization of photonic reservoir computing is the need for the use of photonic integrated circuits. Herein, we experimentally demonstrate reservoir computing using a photonic integrated circuit with a semiconductor laser and a short external cavity. We propose a method to increase the number of virtual nodes in delayed feedback using short node intervals and outputs from multiple delay times. We perform time-series prediction and nonlinear channel equalization tasks using reservoir computing with the photonic integrated circuit. We show that the photonic integrated circuit with optical feedback outperforms the photonic integrated circuit without optical feedback for prediction tasks. To enhance the memory effect we feed past input signals in the current input data and demonstrate successful performance in an n-step-ahead prediction task.

We investigate common-signal-induced synchronization in two multi-mode semiconductor lasers subject to a bandwidth-limited optical noise signal. Synchronization can be achieved when the number of longitudinal modes is matched between the two lasers. The peak wavelengths need to be matched between the two lasers to achieve synchronization. In contrast, small correlation is observed when the peak wavelengths are mismatched. The synchronization is degraded as the number of longitudinal modes in one of the lasers is decreased. However, large correlation is obtained if the overlapped modes are selected and compared. We discuss the possibility of an unauthorized user reproducing the synchronized waveforms. It is difficult to completely reproduce the synchronized waveforms using synchronization if the bandwidth of the noise drive signal is limited.

Background: Alveolar bone is a critical tissue for tooth retention; however, once alveolar bone is lost, it may not spontaneously regenerate. Currently, bone grafts or artificial bone is commonly used for alveolar bone regeneration therapy. However, these therapies require surgical procedures, which present risks, particularly in elderly patients. Therefore, development of alveolar bone regeneration techniques that do not require surgical procedures is critical. It is well known that stem cells present in the periosteal and periodontal ligament may be induced to differentiate into osteogenic cells. This study hypothesizes that transfer of the bone morphogenetic protein-2/7 (BMP-2/7) gene into periodontal tissues via in vivo electroporation induces exogenous BMP production and causes stem cells in periodontal tissues to differentiate into osteogenic cells, enabling generation of new alveolar bone., Method: The BMP-2/7 gene expression vector was introduced via electroporation into the target site in periodontal tissues of the first molar of rat maxillae., Results: Exogenous BMP-2 and -7 were detected in the target areas, and growth of new alveolar bone tissue was observed 5 days after gene transfer. On day 7, new alveolar bone tissues were found to connect to the original bone tissues. Moreover, mineral apposition rates of the alveolar bone after BMP-2/7 gene transfer were significantly higher than those in the control group after LacZ gene transfer., Conclusion: The present findings indicate that a combination of the BMP-2/7 non-viral vector and in vivo electroporation represents a promising non-surgical option for alveolar bone regeneration therapy., (© 2018 American Academy of Periodontology.)

We experimentally achieve common-signal-induced synchronization in two photonic integrated circuits with short external cavities driven by a constant-amplitude random-phase light. The degree of synchronization can be controlled by changing the optical feedback phase of the two photonic integrated circuits. The change in the optical feedback phase leads to a significant redistribution of the spectral energy of optical and RF spectra, which is a unique characteristic of PICs with the short external cavity. The matching of the RF and optical spectra is necessary to achieve synchronization between the two PICs, and stable synchronization can be obtained over an hour in the presence of optical feedback. We succeed in generating information-theoretic secure keys and achieving the final key generation rate of 184 kb/s using the PICs.

Last year in the European Journal of Nuclear Medicine and Molecular Imaging, we introduced some recent nuclear medicine research conducted in Japan. This was favorably received by European readers in the main. This year we wish to focus on the Annals of Nuclear Medicine on some of the fine nuclear medicine research work executed in Europe recently. In the current review article, we take up five topics: prostate-specific membrane antigen imaging, recent advances in radionuclide therapy, [ 18 F]fluorodeoxyglucose positron-emission tomography (PET) for dementia, quantitative PET assessment of myocardial perfusion, and iodine-124 ( 124 I). Just at the most recent annual meeting of the European Association of Nuclear Medicine 2016, Kyoto was selected as the host city for the 2022 Congress of the World Federation of Nuclear Medicine and Biology. We hope that our continuous efforts to strengthen scientific cooperation between Europe and Japan will bring many European friends and a great success to the Kyoto meeting.

Bevacizumab, an anti-vascular endothelial growth factor (VEGF) antibody, is an antiangiogenic agent clinically used for various cancers. However, repeated use of this agent leads to tumor-decreased vascularity and hypoxia with activation of an HIF-1 signaling pathway, which results in drug delivery deficiency and induction of malignant behaviors in tumors. Here, we developed a novel strategy to treat tumors with bevacizumab-induced vascular decrease and hypoxia using 64 Cu-diacetyl-bis ( N 4 -methylthiosemicarbazone) ( 64 Cu-ATSM), a potential theranostic agent, which possesses high tissue permeability and can target over-reduced conditions under hypoxia in tumors, with a human colon carcinoma HT-29 tumor-bearing mouse model. The long-term treatment with bevacizumab caused decreased blood vessel density and activation of an HIF-1 signaling pathway; increased uptake of 64 Cu-ATSM was also observed despite limited blood vessel density in HT-29 tumors. In vivo high-resolution SPECT/PET/CT imaging confirmed reduced vascularity and increased proportion of 64 Cu-ATSM uptake areas within the bevacizumab-treated tumors. 64 Cu-ATSM therapy was effective to inhibit tumor growth and prolong survival of the bevacizumab-treated tumor-bearing mice without major adverse effects. In conclusion, 64 Cu-ATSM therapy effectively enhanced anti-tumor effects in tumors with bevacizumab-induced vascular decrease and hypoxia. 64 Cu-ATSM therapy could represent a novel approach as an add-on to antiangiogenic therapy., Competing Interests: CONFLICTS OF INTEREST Hiroki Matsumoto is an employee of Nihon Medi-Physics Co., Ltd. All the other authors declare no competing financial interests.

Synchronization properties of chaotic dynamics in two mutually coupled semiconductor lasers with optical feedback embedded in a photonic integrated circuit are investigated from the point of view of their dynamical content. A phenomenon in which the two lasers can show qualitatively different synchronization properties according to the frequency range of investigation and their nonlinear dynamics is identified and termed dynamics-dependent synchronization. In-phase synchronization is observed for original signals and antiphase synchronization is observed for low-pass filtered signals in the case where one of the lasers shows chaotic oscillations while the other laser exhibits low-frequency fluctuations dynamics. The experimental conditions causing the synchronization states to vary according to the considered frequency interval are studied and the key roles of asymmetric coupling strength and injection currents are clarified.

Reservoir computing is a brain-inspired machine learning framework that employs a signal-driven dynamical system, in particular harnessing common-signal-induced synchronization which is a widely observed nonlinear phenomenon. Basic understanding of a working principle in reservoir computing can be expected to shed light on how information is stored and processed in nonlinear dynamical systems, potentially leading to progress in a broad range of nonlinear sciences. As a first step toward this goal, from the viewpoint of nonlinear physics and information theory, we study the memory-nonlinearity trade-off uncovered by Dambre et al. (2012). Focusing on a variational equation, we clarify a dynamical mechanism behind the trade-off, which illustrates why nonlinear dynamics degrades memory stored in dynamical system in general. Moreover, based on the trade-off, we propose a mixture reservoir endowed with both linear and nonlinear dynamics and show that it improves the performance of information processing. Interestingly, for some tasks, significant improvements are observed by adding a few linear dynamics to the nonlinear dynamical system. By employing the echo state network model, the effect of the mixture reservoir is numerically verified for a simple function approximation task and for more complex tasks.

We demonstrate physical implementation of information-theoretic secure oblivious transfer based on bounded observability using optical correlated randomness in semiconductor lasers driven by common random light broadcast over optical fibers. We demonstrate that the scheme can achieve one-out-of-two oblivious transfer with effective key generation rate of 110 kb/s. The results show that this scheme is a promising approach to achieve information-theoretic secure oblivious transfer over long distances for future applications of secure computation such as privacy-preserving database mining, auctions and electronic-voting.