High-Fat Diet-Induced Diabetic Conditions Exacerbate Cognitive Impairment in a Mouse Model of Alzheimer's Disease Via a Specific Tau Phosphorylation Pattern

BACKGROUND

Epidemiological evidence has demonstrated a clear association between diabetes mellitus and increased risk of Alzheimer's disease (AD). Cerebral accumulation of phosphorylated tau aggregates, a cardinal neuropathological feature of AD, is associated with neurodegeneration and cognitive decline. Clinical and experimental studies indicate that diabetes mellitus affects the development of tau pathology; however, the underlying molecular mechanisms remain unknown.

OBJECTIVE

In the present study, we used a unique diabetic AD mouse model to investigate the changes in tau phosphorylation patterns occurring in the diabetic brain.

DESIGN

Tau-transgenic mice were fed a high-fat diet (n = 24) to model diabetes mellitus. These mice developed prominent obesity, severe insulin resistance, and mild hyperglycemia, which led to early-onset neurodegeneration and behavioral impairment associated with the accumulation of hyperphosphorylated tau aggregates.

RESULTS

Comprehensive phosphoproteomic analysis revealed a unique tau phosphorylation signature in the brains of mice with diabetic AD. Bioinformatic analysis of the phosphoproteomics data revealed putative tau-related kinases and cell signaling pathways involved in the interaction between diabetes mellitus and AD.

CONCLUSION

These findings offer potential novel targets that can be used to develop tau-based therapies and biomarkers for use in AD.

First observation of 28O

Subjecting a physical system to extreme conditions is one of the means often used to obtain a better understanding and deeper insight into its organization and structure. In the case of the atomic nucleus, one such approach is to investigate isotopes that have very different neutron-to-proton (N/Z) ratios than in stable nuclei. Light, neutron-rich isotopes exhibit the most asymmetric N/Z ratios and those lying beyond the limits of binding, which undergo spontaneous neutron emission and exist only as very short-lived resonances (about 10-21 s), provide the most stringent tests of modern nuclear-structure theories. Here we report on the first observation of 28O and 27O through their decay into 24O and four and three neutrons, respectively. The 28O nucleus is of particular interest as, with the Z = 8 and N = 20 magic numbers1,2, it is expected in the standard shell-model picture of nuclear structure to be one of a relatively small number of so-called 'doubly magic' nuclei. Both 27O and 28O were found to exist as narrow, low-lying resonances and their decay energies are compared here to the results of sophisticated theoretical modelling, including a large-scale shell-model calculation and a newly developed statistical approach. In both cases, the underlying nuclear interactions were derived from effective field theories of quantum chromodynamics. Finally, it is shown that the cross-section for the production of 28O from a 29F beam is consistent with it not exhibiting a closed N = 20 shell structure.

OpenKBP-Opt: an international and reproducible evaluation of 76 knowledge-based planning pipelines

Objective.To establish an open framework for developing plan optimization models for knowledge-based planning (KBP).Approach.Our framework includes radiotherapy treatment data (i.e. reference plans) for 100 patients with head-and-neck cancer who were treated with intensity-modulated radiotherapy. That data also includes high-quality dose predictions from 19 KBP models that were developed by different research groups using out-of-sample data during the OpenKBP Grand Challenge. The dose predictions were input to four fluence-based dose mimicking models to form 76 unique KBP pipelines that generated 7600 plans (76 pipelines × 100 patients). The predictions and KBP-generated plans were compared to the reference plans via: the dose score, which is the average mean absolute voxel-by-voxel difference in dose; the deviation in dose-volume histogram (DVH) points; and the frequency of clinical planning criteria satisfaction. We also performed a theoretical investigation to justify our dose mimicking models.Main results.The range in rank order correlation of the dose score between predictions and their KBP pipelines was 0.50-0.62, which indicates that the quality of the predictions was generally positively correlated with the quality of the plans. Additionally, compared to the input predictions, the KBP-generated plans performed significantly better (P< 0.05; one-sided Wilcoxon test) on 18 of 23 DVH points. Similarly, each optimization model generated plans that satisfied a higher percentage of criteria than the reference plans, which satisfied 3.5% more criteria than the set of all dose predictions. Lastly, our theoretical investigation demonstrated that the dose mimicking models generated plans that are also optimal for an inverse planning model.Significance.This was the largest international effort to date for evaluating the combination of KBP prediction and optimization models. We found that the best performing models significantly outperformed the reference dose and dose predictions. In the interest of reproducibility, our data and code is freely available.

Evaluation of two independent dose prediction methods to personalize the automated radiotherapy planning process for prostate cancer

Background and purpose

Currently, automatic approaches for radiotherapy planning are widely used, however creation of high quality treatment plans is still challenging. In this study, two independent dose prediction methods were used to personalize the initial settings for the automated planning template for optimizing prostate cancer treatment plans. This study evaluated the dose metrics of these plans comparing both methods with the current clinical automated prostate cancer treatment plans.

Material and methods

Datasets of 20 high-risk prostate cancer treatment plans were taken from our clinical database. The prescription dose for these plans was 70 Gy given in fractions of 2.5 Gy. Plans were replanned using the current clinical automated treatment and compared with two personalized automated planning methods. The feasibility dose volume histogram (FDVH) and modified filter back projection (mFBP) methods were used to calculate independent dose predictions. Parameters for the initial objective values of the planning template were extracted from these predictions and used to personalize the optimization of the automated planning process.

Results

The current automated replanned clinical plans and the automated plans optimized with the personalized template methods fulfilled the clinical dose criteria. For both methods a reduction in the average mean dose of the rectal wall was found, from 22.5 to 20.1 Gy for the FDVH and from 22.5 to 19.6 Gy for the mFBP method.

Conclusions

With both dose-prediction methods the initial settings of the template could be personalized. Hereby, the average dose to the rectal wall was reduced compared to the standard template method.

Pairing Forces Govern Population of Doubly Magic ^{54}Ca from Direct Reactions

Direct proton-knockout reactions of ^{55}Sc at ∼220  MeV/nucleon were studied at the RIKEN Radioactive Isotope Beam Factory. Populated states of ^{54}Ca were investigated through γ-ray and invariant-mass spectroscopy. Level energies were calculated from the nuclear shell model employing a phenomenological internucleon interaction. Theoretical cross sections to states were calculated from distorted-wave impulse approximation estimates multiplied by the shell model spectroscopic factors, which describe the wave function overlap of the ^{55}Sc ground state with states in ^{54}Ca. Despite the calculations showing a significant amplitude of excited neutron configurations in the ground-state of ^{55}Sc, valence proton removals populated predominantly the ground state of ^{54}Ca. This counterintuitive result is attributed to pairing effects leading to a dominance of the ground-state spectroscopic factor. Owing to the ubiquity of the pairing interaction, this argument should be generally applicable to direct knockout reactions from odd-even to even-even nuclei.

Impact of lipoprotein(a) levels on angiographic severity of femoropopliteal lesions

Background

High lipoprotein(a) [Lp(a)] levels are a risk factor for peripheral artery disease (PAD). However, the association between Lp(a) levels and angiographic severity of PAD has not been systematically studied.

Purpose

The aim of this study was to assess the impact of Lp(a) levels on angiographic severity of femoropopliteal lesions in patients with PAD.

Methods

We retrospectively analyzed a single-center database including 108 patients (74±8 years, 69% male) who underwent endovascular therapy for de novo femoropopliteal lesions and measured Lp(a) levels before therapy between June 2016 and September 2019. Patients were divided into low Lp(a) [LP(a) &lt;30 mg/dL; 77 patients] and high Lp(a) [LP(a) ≥30 mg/dL; 31 patients] groups. Trans-Atlantic Inter-Society Consensus (TASC) II classification, calcification [referring to peripheral arterial calcium scoring system (PACSS) classification] and lesion length were compared between the groups.

Results

Median Lp(a) was 16 (7–31) mg/dL.The prevalence of TASC II class D (13% vs 38%, P&lt;0.01) and severe calcification (PACSS 4) (6% vs 23%, P=0.02) was significantly higher and lesion length was longer (123±88 mm vs 175±102 mm, P&lt;0.01) in the high Lp(a) group than in the low Lp(a) group.(Table and Figure) In multivariate analysis, Lp(a)≥30 was an independent predictor for TASC II class D (HR=3.67, P=0.02) and PACSS 4 (HR=4.97, P=0.02) prevalence.

Conclusion

Lp(a) was associated with angiographic severity of femoropopliteal lesions in patients with PAD.

Comparison of angiographic severity

Funding Acknowledgement

Type of funding source: None

Differential expression levels of CD151 enable enrichment of atrial cardiomyocytes derived from human induced-pluripotent stem cell

Introduction

Human iPSCs-derived cardiomyocytes (hiPSCs-CMs) are heterogeneous populations that contain ventricular-like CMs (VCMs), atrial-like CMs (ACMs) and pacemaker cells. Isolation of pure populations of each hiPSCs-CM subtype corresponding to the target regions of the heart enables effective drug screening process and stable engraftment of hiPSCs-CMs (e.g. ventricular cardiomyocytes without impurities).

Purpose

Atrial and ventricular cardiomyocytes develop from distinct mesoderm populations, and many of different genes are expressed between two subtypes. Since our method of cardiomyocytes differentiation from hiPSCs mimics in vivo cardiomyocytes development, we hypothesized that two subtypes could be separated by differentially expressed genes in hiPSCs-CMs differentiation process. In this study, we focused cell surface genes which are useful for analysis by flow cytometry, and then identified cell surface marker that can distinguish atrial and ventricular cardiomyocytes from hiPSCs-CMs.

Methods

We performed an antibody-based screening using hiPSCs-CMs induced under atrial induction condition (AIC) and ventricular induction condition (VIC) by flow cytometry. To identify cell surface markers which enable discrimination of cardiac subtypes, we isolated the cell populations using the antibodies against the cell surface markers. Quantitative PCR was performed to analyze expression levels of subtype-specific genes in sorted cells. We confirmed subtype classification of cells using patch-clamp method.

Results

We identified CD151 as a novel candidate of atrial/ventricular selectable marker. The expression level of CD151 was low in most hiPSCs-CMs under AIC. In these cells, CD151-low cells highly expressed atrial genes compared to CD151-high cells. In contrast, the expression level of CD151 was high in most hiPSCs-CMs under VIC. In these cells, CD151-high cells highly expressed ventricular genes compared to CD151-low cells. Furthermore, we investigated the electrophysiological properties of CD151-high and -low cells using patch-clamp experiments. As expected, the cells showing atrial type action potential were enriched in AIC with low expression of CD151 (n=17). On the other hand, CD151-high cells (n=16) contained no atrial CMs, but mostly nodal like cells. In addition, CD151-low cells in AIC were affected with action potential duration by exposure of atrial specific channel blocker (4-aminopyridine) and activator (carbachol). In VIC, CD151-high cells (n=16) demonstrated ventricular type action potential property compared to CD151-low cells (n=21).

Conclusion

These results suggest that CD151 is a useful marker which can enrich ACMs from hiPSCs-CMs. Because these enriched ACMs are uniform population, it may be appropriate for atrial-selective drug screening. Additionally, this marker can reduce contaminated ACMs from hiPSCs-CMs cultured in VIC.

Action potential of CD151-high/low CMs

Funding Acknowledgement

Type of funding source: Other. Main funding source(s): Takeda pharmaceutical company limited, Japan society for the promotion of science(JSPS) KAKENHI

PD-L1 expression in tongue squamous cell carcinoma

PURPOSE

Immune checkpoint proteins programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PD-L1) are important therapeutic targets for head and neck cancer. This large-scale case study aimed to analyze tongue squamous cell carcinomas (SCCs) and evaluate the correlation between PD-L1 expression and clinical prognosis. So far, this study is the largest case study on PD-L1 expression in tongue SCCs.

METHODS

This is a case-control study that analyzed 121 tongue SCCs. Paraffin-embedded sections and clinical data were obtained retrospectively and immunohistochemistry with PD-L1 was performed.

RESULTS

11.6% contained ≥ 50% of PD-L1-positive cells, 57.1% of these cases had a poor prognosis with nodal metastasis. Among cases of T1/2 primary lesions with nodal metastasis, cases of high PD-L1 expression had a significantly shorter disease-free survival than cases of no PD-L1 expression (p = 0.018). The hazard ratio for high PD-L1 expression was 3.21 (95 per cent CI, 1.26-8.72) compared with no PD-L1 expression after adjusting for other factors.

CONCLUSIONS

These data indicate that PD-L1 upregulation in tongue SCCs is associated with a more advanced stage and shorter disease-free survival. PD-1/PD-L1 inhibitors might hence constitute potential adjuvant therapy for tongue SCCs with PD-L1 upregulation.

MACC1 expression is an indicator of recurrence in early-stage glottic cancer

BACKGROUND

Metastasis-associated in colon cancer 1 (MACC1) has been reported to be an independent indicator of poor prognoses in some kinds of cancer due to disease metastasis or recurrence. We investigated the correlation between MACC1 expression and the prognosis of glottic cancer.

METHODS

Paraffin-embedded, early-stage (I or II) glottic cancer specimens (n = 52) were immunohistochemically analyzed to explore MACC1 expression. The clinical records associated with each case were also examined. Recurrence-free survival (RFS) was estimated using the Kaplan-Meier method, and between-group RFS differences were assessed using the log-rank test. The multivariate analyses were evaluated using the Cox's proportional-hazard model.

RESULTS

Patients were treated with only radiotherapy (RT) (n = 37, including 18 with T1 disease and 19 with T2 disease), or with chemoradiotherapy (CRT) (n = 15, including 1 with T1 disease and 14 with T2 disease). Eleven patients demonstrated local recurrence and two patients experienced cervical lymph node recurrence. Tumor specimens were MACC1-positive in 9 of the 13 (69.2%) patients with local or neck recurrence, and 7 of the 11 (63.6%) patients with local recurrence. The RFS rate of patients who were treated with only RT was significantly lower than that of patients who were treated with CRT (P = 0.0243). The RFS rate was significantly lower in cases with MACC1 expression than in those without MACC1 expression (P = 0.0003). Multivariate analysis revealed that MACC1 expression was an independent risk factor of local recurrence (P = 0.0016).

CONCLUSION

MACC1 is an independent indicator of recurrence related to RFS in early-stage glottic cancer.

Extending the Southern Shore of the Island of Inversion to ^{28}F

Detailed spectroscopy of the neutron-unbound nucleus ^{28}F has been performed for the first time following proton/neutron removal from ^{29}Ne/^{29}F beams at energies around 230  MeV/nucleon. The invariant-mass spectra were reconstructed for both the ^{27}F^{(*)}+n and ^{26}F^{(*)}+2n coincidences and revealed a series of well-defined resonances. A near-threshold state was observed in both reactions and is identified as the ^{28}F ground state, with S_{n}(^{28}F)=-199(6)  keV, while analysis of the 2n decay channel allowed a considerably improved S_{n}(^{27}F)=1620(60)  keV to be deduced. Comparison with shell-model predictions and eikonal-model reaction calculations have allowed spin-parity assignments to be proposed for some of the lower-lying levels of ^{28}F. Importantly, in the case of the ground state, the reconstructed ^{27}F+n momentum distribution following neutron removal from ^{29}F indicates that it arises mainly from the 1p_{3/2} neutron intruder configuration. This demonstrates that the island of inversion around N=20 includes ^{28}F, and most probably ^{29}F, and suggests that ^{28}O is not doubly magic.

Development of a CT number calibration audit phantom in photon radiation therapy: A pilot study

PURPOSE

In photon radiation therapy, computed tomography (CT) numbers are converted into values for mass density (MD) or relative electron density to water (RED). CT-MD or CT-RED calibration tables are relevant for human body dose calculation in an inhomogeneous medium. CT-MD or CT-RED calibration tables are influenced by patient imaging (CT scanner manufacturer, scanning parameters, and patient size), the calibration process (tissue-equivalent phantom manufacturer, and selection of tissue-equivalent material), differences between tissue-equivalent materials and standard tissues, and the dose calculation algorithm applied; however, a CT number calibration audit has not been established. The purposes of this study were to develop a postal audit phantom, and to establish a CT number calibration audit process.

METHODS

A conventional stoichiometric calibration conducts a least square fit of the relationships between the MD, material weight, and measured CT number, using two parameters. In this study, a new stoichiometric CT number calibration scheme has been empirically established, using three parameters to harmonize the calculated CT number with the measured CT number for air and lung tissue. In addition, the suitable material set and the minimal number of materials required for stoichiometric CT number calibration were determined. The MDs and elemental weights from the International Commission on Radiological Protection Publication 110 were used as standard tissue data, to generate the CT-MD and CT-RED calibration tables. A small-sized, CT number calibration phantom was developed for a postal audit, and stoichiometric CT number calibration with the phantom was compared to the CT number calibration tables registered in the radiotherapy treatment planning systems (RTPSs) associated with five radiotherapy institutions.

RESULTS

When a least square fit was performed for the stoichiometric CT number calibration with the three parameters, the calculated CT number showed better agreement with the measured CT number. We established stoichiometric CT number calibration using only two materials because the accuracy of the process was determined not by the number of used materials but by the number of elements contained. The stoichiometric CT number calibration was comparable to the tissue-substitute calibration, with a dose difference less than 1%. An outline of the CT number calibration audit was demonstrated through a multi-institutional study.

CONCLUSIONS

We established a new stoichiometric CT number calibration method for validating the CT number calibration tables registered in RTPSs. We also developed a CT number calibration phantom for a postal audit, which was verified by the performances of multiple CT scanners located at several institutions. The new stoichiometric CT number calibration has the advantages of being performed using only two materials, and decreasing the difference between the calculated and measured CT numbers for air and lung tissue. In the future, a postal CT number calibration audit might be achievable using a smaller phantom.

P937Impact of left ventricular diastolic dysfunction on long-term outcome in patients with lower extremity artery disease

Background

Left ventricular (LV) systolic dysfunction and heart failure (HF) in patients with lower extremity artery disease (LEAD) is associated with an increased risk for adverse events. However, relationship between long-term outcome in patient with LEAD and LV diastolic dysfunction remains unclear.

Purpose

The aim of this study was to assess the impact of LV diastolic dysfunction on long-term outcome in patients with LEAD.

Methods

Two hundred patients (male 66%, mean age 76±9 years) with preserved LV systolic function assessed by echocardiography (ejection fraction ≥50%) were enrolled from a single-center database between January 2013 to May 2015. Baseline LEAD was identified by ABI <0.9 or history of lower extremity revascularization. Diagnosis of LV diastolic dysfunction was based on the ASE/EACVI guidelines. The 3-year cumulative incidence of primary endpoint compared between LEAD patients with LV diastolic dysfunction than those without. The primary endpoint was a composite of cardiovascular death, myocardial infarction, stroke and hospitalization for HF during 3 years follow-up. Multivariate analysis was performed to determine whether LV diastolic dysfunction was independently associated with the primary endpoint.

Results

LV diastolic dysfunction was identified in 31%. The mean observation period was 32±21 months. The primary endpoint occurred more frequently in patients with LV diastolic dysfunction than those without at 3 years (30% vs 16%, P=0.02). There were no significant differences between 2 groups in the myocardial infarction (3% vs 3%, P=0.73) and stroke (3% vs 3%, P=0.55). Cardiovascular death (19% vs 7%, P=0.01) and hospitalization for HF (19% vs 7%, P=0.01) were significantly higher in patients with LV diastolic dysfunction. In multivariate analysis, LV diastolic dysfunction was an independent predictor for primary endpoint (HR=2.28, 95% CI 1.10–4.73, P=0.02) (Table)

Predictor for primary endpoint Factors Univariate model Multivariate model Hazard ratio [95% CI] P value Hazard ratio [95% CI] P value Age 1.03 [0.98–1.08] 0.24 1.03 [0.98–1.08] 0.22 Chronic kidney disease 1.53 [0.77–3.07] 0.23 1.25 [0.60–2.58] 0.55 Coronary artery disease 1.08 [0.53–2.18] 0.84 1.18 [0.56–2.50] 0.65 Cerebrovascular disease 1.93 [0.74–5.02] 0.17 2.28 [0.86–6.05] 0.10 Critical limb ischemia 3.75 [1.68–8.37] <0.01 3.72 [0.56–2.50] <0.01 LV diastolic dysfunction 2.37 [1.18–4.74] 0.02 2.28 [1.10–4.73] 0.03

Conclusions

LV diastolic dysfunction increased the risk for adverse events in patients with LEAD.

Acknowledgement/Funding

None

P4591Impact of extent of non-culprit lesions on one-year outcomes in patients with acute myocardial infarction

Background

Presence of severe stenosis in non-infarct related arteries, i.e. multi-vessel disease (MVD), is associated with poor outcomes after acute myocardial infarction (AMI). However, impact of mild to moderate stenosis in non-culprit lesions remains unclear.Gensini score is an angiographic application grading the extent of coronary artery lesions including mild to moderate stenosis.

Purpose

To evaluate whether the extent of non-culprit lesion is related to one-year outcomes after AMI.

Methods

This study consisted of consecutive 168 patients who underwent primary percutaneous coronary intervention (PPCI) for AMI between 2015 and 2017. Patients with coronary bypass grafts were excluded from the analysis. To assess the extent of non-culprit lesions, we used “non-culprit Gensini score”, which is calculated by excluding score of the culprit lesion from the original Gensini score. Patients were divided into 2 groups by the median ofnon-culprit Gensini score: low score (0–14, n=84) and high score (>15, n=84). Major adverse cardiac events (MACE) included all cause of deaths, non-fatal MI, stroke and ischemia driven coronary revascularization during one-year follow-up period.

Results

MVDwas more frequent in patients with high score than those in those with low score (90% vs 25%, P<0.05). Kaplan-Mayer curves of patients with and without MVD are shown in left figure, and curves of patients with low score and those with high score are shown in right figure. Multivariable analysis showed that high score was an independent predictor of one-year MACE (HR 5.28, 95% CI 1.93–14.9, P<0.05), but MVD was not (HR 0.56, 95% CI 0.23–1.54, P=0.25) (Table).

Multivariable analyses Univariable analyses Multivariable analyses HR (95% CI) P-value HR (95% CI) P-value Age 1.03 (1.01, 1.06) <0.05 1.15 (0.99, 1.05) 0.31 eGFR (<45ml/min/1.73m2) 2.95 (1.59, 5.38) <0.05 2.35 (1.26, 4.35) <0.05 Multi-vessel disease 1.84 (1.01, 3.55) <0.05 0.56 (0.23, 1.54) 0.25 Non-culprit-Gensini score (>15) 3.37 (1.79, 6.78) <0.05 5.28 (1.93, 14.9) <0.05 HR = hazard ratio; CI = confidence interval; eGFR = estimated glomerular filtration rate.

Kaplan-Meier curves

Conclusion

These findings suggested that extent of mild to moderate stenosis in non-culprit lesions might affect the prognosis after AMI in patients undergoing PPCI. Non-culprit Gensini score may be useful to predict outcomes of patients with AMI.

Acknowledgement/Funding

None

Potential survival of the lichen Caloplaca flavovirescens under high helium-beam doses

Testing the limits of survivability in space is the primary focus in astrobiological research. Although a number of previous studies have examined terrestrial life survival in an extraterrestrial environment, only a few have investigated how life systems respond to high doses of alpha cosmic ray, the main component of cosmic rays. We used respiration and photosynthetic rates as indicators of the vital signs of the lichen Caloplaca flavovirescens, which is a symbiotic life form including fungi and algae. Our experiment demonstrated that the photosynthetic rate decreased with increased helium-beam doses, whereas the respiration rate was relatively unaffected. Specifically, under a helium-beam dose greater than 10 Gy, the respiration rate remained nearly constant regardless of further increases in the radiation rate. Our results indicate that the different metabolic systems of terrestrial life forms might exhibit different survival characteristics when they are in space.

Beam Energy and Centrality Dependence of Direct-Photon Emission from Ultrarelativistic Heavy-Ion Collisions

The PHENIX collaboration presents first measurements of low-momentum (0.4<p_{T}<3  GeV/c) direct-photon yields from Au+Au collisions at sqrt[s_{NN}]=39 and 62.4 GeV. For both beam energies the direct-photon yields are substantially enhanced with respect to expectations from prompt processes, similar to the yields observed in Au+Au collisions at sqrt[s_{NN}]=200. Analyzing the photon yield as a function of the experimental observable dN_{ch}/dη reveals that the low-momentum (>1  GeV/c) direct-photon yield dN_{γ}^{dir}/dη is a smooth function of dN_{ch}/dη and can be well described as proportional to (dN_{ch}/dη)^{α} with α≈1.25. This scaling behavior holds for a wide range of beam energies at the Relativistic Heavy Ion Collider and the Large Hadron Collider, for centrality selected samples, as well as for different A+A collision systems. At a given beam energy, the scaling also holds for high p_{T} (>5  GeV/c), but when results from different collision energies are compared, an additional sqrt[s_{NN}]-dependent multiplicative factor is needed to describe the integrated-direct-photon yield.

KRAS mutations in tongue squamous cell carcinoma

Background: p16^INK4a (p16) expression in tongue cancer (TC) is reportedly not associated with human papilloma virus (HPV). Mutations of KRAS in cancer cells are most frequently observed within codon 12. However, few reports have investigated the association between KRAS mutations and p16 status in TC. Objectives: This study aimed to evaluate the influence of KRAS mutations on TC. Methods: Clinical records and surgically resected specimens of 85 TC patients were analyzed. Tumor samples were analyzed for mutations of KRAS located within codons 12 and 13. p16 staining was performed and considered positive in cases with moderate to strong nuclear and cytoplasmic staining. Results: Positive p16 staining was observed in 10 cases (11.8%). A KRAS mutation was detected in one case (1.2%). The case with KRAS mutation showed negative p16 staining. Despite being at an early stage, the patient died of lung metastasis at 43 months from initial treatment. Conclusions and Significance: KRAS mutations are not associated with p16 expression in TC and may predict poor prognosis in TC patients. Further analysis of mutations in regions other than codons 12 and 13 of KRAS will be necessary to determine the relationship between KRAS mutations and prognosis of this disease.

Short communication: Effects of feeding purple corn (Zea mays L.) silage on productivity and blood superoxide dismutase concentration in lactating cows

The objective of this study was to evaluate the effects of feeding purple corn (Zea mays L.) silage on productivity and blood superoxide dismutase concentration in lactating cows. We hypothesized that feeding purple corn silage (AX-152; Nagano Animal Industry Experiment Station, Nagano, Japan, and Takii and Co. Ltd., Tokyo, Japan), which is high in anthocyanin content, would increase milk production and blood concentration of superoxide dismutase. We assigned 16 Holstein cows (8 primiparous and 8 multiparous) in mid lactation to 1 of 2 treatments in a randomized block design, with efforts to balance parity, body weight, and days in milk between treatments. Experimental diets contained either purple corn silage [PCS; 31.2% dry matter (DM), 8.4% crude protein, 40.2% neutral detergent fiber, and 26.6% starch] or conventional corn silage (CONT; 30.5% dry matter, 8.7% crude protein, 42.1% neutral detergent fiber, and 26.5% starch) at approximately 32% of diet DM. Both PCS and CONT were ensiled for 5 mo before the study. Treatment diets were fed as total mixed rations ad libitum for 12 wk from February 1 to April 25, 2016. Cows fed the PCS had increased milk yield (31.7 vs. 29.2 kg/d) and blood superoxide dismutase concentrations (9,333 vs. 8,467 U/mL) compared with those fed CONT. However, anthocyanin concentration in the PCS decreased over the 12-wk experiment: 70 mg/kg of DM for the first 4 wk, 20 mg/kg of DM for the second 4 wk, and undetectable for the last 4 wk. We did not detect anthocyanins in the CONT group at any time point. Feeding PCS may increase antioxidant capacity and milk production in dairy cows, but anthocyanin in PCS may be degraded during storage.

Tolerance levels of mass density for CT number calibration in photon radiation therapy

Computed tomography (CT) data are required to calculate the dose distribution in a patient's body. Generally, there are two CT number calibration methods for commercial radiotherapy treatment planning system (RTPS), namely CT number-relative electron density calibration (CT-RED calibration) and CT number-mass density calibration (CT-MD calibration). In a previous study, the tolerance levels of CT-RED calibration were established for each tissue type. The tolerance levels were established when the relative dose error to local dose reached 2%. However, the tolerance levels of CT-MD calibration are not established yet. We established the tolerance levels of CT-MD calibration based on the tolerance levels of CT-RED calibration. In order to convert mass density (MD) to relative electron density (RED), the conversion factors were determined with adult reference computational phantom data available in the International Commission on Radiological Protection publication 110 (ICRP-110). In order to validate the practicability of the conversion factor, the relative dose error and the dose linearity were validated with multiple RTPSes and dose calculation algorithms for two groups, namely, CT-RED calibration and CT-MD calibration. The tolerance levels of CT-MD calibration were determined from the tolerance levels of CT-RED calibration with conversion factors. The converted RED from MD was compared with actual RED calculated from ICRP-110. The conversion error was within ±0.01 for most standard organs. It was assumed that the conversion error was sufficiently small. The relative dose error difference for two groups was less than 0.3% for each tissue type. Therefore, the tolerance levels for CT-MD calibration were determined from the tolerance levels of CT-RED calibration with the conversion factors. The MD tolerance levels for lung, adipose/muscle, and cartilage/spongy-bone corresponded to ±0.044, ±0.022, and ±0.045 g/cm3 , respectively. The tolerance levels were useful in terms of approving the CT-MD calibration table for clinical use.

Commissioning of a respiratory gating system involving a pressure sensor in carbon-ion scanning radiotherapy

This study reports the commissioning methodology and results of a respiratory gating system [AZ - 733 V/733 VI (Anzai Medical Co., Japan)] using a pressure sensor in carbon-ion scanning radiotherapy. Commissioning includes choosing a location and method for pressure sensor installation, delay time measurement of the system, and the final flow test. Additionally, we proposed a methodology for the determination of a threshold level of generating an on/off gate for the beam to the respiratory waveform, which is important for clinical application. Regarding the location and method for installation of the pressure sensor, the actual person's abdomen, back of the body position, and supine/prone positioning were checked. By comparing the motion between the pressure sensor output and the reference LED sensor motion, the chest rear surface was shown to be unsuitable for the sensor installation, due to noise in the signal caused by the cardiac beat. Regarding delay time measurement of the system, measurements were performed for the following four steps: (a). Actual motion to wave signal generation; (b). Wave signal to gate signal generation; (c). Gate signal to beam on/off signal generation; (d). Beam on/off signal to the beam irradiation. The total delay time measured was 46 ms (beam on)/33 ms (beam off); these were within the prescribed tolerance time (<100 ms). Regarding the final flow test, an end-to-end test was performed with a patient verification system using an actual carbon-ion beam; the respiratory gating irradiation was successfully performed, in accordance with the intended timing. Finally, regarding the method for determining the threshold level of the gate generation of the respiration waveform, the target motion obtained from 4D-CT was assumed to be correlated with the waveform obtained from the pressure sensor; it was used to determine the threshold value in amplitude direction.

Young adult patients with squamous cell carcinoma of the tongue strongly express p16 without human papillomavirus infection

BACKGROUND

Long-term smoking and drinking are known to contribute to the onset of tongue cancer (TC). However, the increasing incidence of TC in younger adults has been suggested to be associated with other factors.

OBJECTIVES

The present study investigated the relationship between TC and human papillomavirus (HPV) infection.

MATERIAL AND METHODS

Clinical records and surgically resected specimens from 86 patients (<40-years-old, n = 12; ≥40-years-old, n = 74) with TC were analyzed. Strong nuclear and cytoplasmic p16 staining was considered positive. HPV DNA (high-risk subtypes: 16, 18, 31, 33, 35, 52b, and 58; low-risk subtypes: 6 and 11) was detected using consensus primer-mediated polymerase chain reaction.

RESULTS

Strong p16 expression was observed in 10 (11.6%) patients. HPV DNA was detected in 9 (10.5%) patients (high-risk subtypes, n = 2; low-risk subtypes, n = 7). Strong p16 expression was observed more frequently among younger adults than among older adults (33.3% vs. 8.1%; p = .045). p16 staining did not correlate with the detection of HPV DNA (correlation coefficient, 0.113; p = .300).

CONCLUSIONS AND SIGNIFICANCE

In TC, p16 expression was not associated with HPV infection, suggesting that it may be caused by a different mechanism.

Computed Tomography Findings for Diagnosing Follicular Thyroid Neoplasms

Since no diagnostic method has been established to distinguish follicular thyroid carcinoma (FTC) from follicular thyroid adenoma (FTA), surgery has been the only way to reach a diagnosis of follicular neoplasm. Here we investigated the computed tomography (CT) features of follicular neoplasms, toward the goal of being able to identify specific CT features allowing the preoperative differentiation of FTC from FTA. We retrospectively analyzed the cases of 205 patients who underwent preoperative CT of the neck and were histopathologically diagnosed with FTC (n=31) or FTA (n=174) after surgery between January 2002 and June 2016 at several hospitals in Japan. In each of these 205 cases, non-enhanced and contrast-enhanced CT images were obtained, and we analyzed the CT features. On univariate analysis, inhomogeneous features of tumor lesions on contrast-enhanced CT were more frequently observed in FTC than in FTA (p=0.0032). A multivariate analysis identified inhomogeneous features of tumor lesions on contrast-enhanced CT images as an independent variable indicative of FTC (p=0.0023). CT thus offers diagnostic assistance in distinguishing FTC from FTA.

Evaluation of optimization workflow using design of experiment (DoE) for various field configurations in volumetric-modulated arc therapy

PURPOSE

In volumetric-modulated arc therapy (VMAT), field configurations such as couch or arc angles are defined manually or using a template. A field configuration is reselected through trial-and-error in the case of undesirable resultant planning. To efficiently plan for desirable quality, configurations should be assessed before dose calculation. Design of experiments (DoE) is an optimization technique that efficiently reveals the influence of inputs on outputs. We developed an original tool using DoE to determine the field configuration selection and evaluated the efficacy of this workflow for clinical practice.

METHODS

Computed-tomography scans of 17 patients and target structures were acquired retrospectively from a brain tumor treated using a dual-arc VMAT plan. The configurations of the couch, arc, collimator angles, field sizes, and beam energy were determined using DoE. The resultant dose distributions obtained using the DoE-selected configuration were compared with the clinical plan.

RESULTS

The averaged differences between the DoE and clinical plan for 17 patients of doses to 50% of the planning target volume (PTV-D50%), Brain-D60%, Brain-D30%, Brain stem-D1%, Left eye-D1%, Right eye-D1%, Optic nerve-D1%, and Chiasm-D1% were 0.2 ± 0.5%, -1.0 ± 4.6%, 1.7 ± 3.5%, -2.5 ± 6.7%, -0.2 ± 4.9%, -1.2 ± 3.6%, -2.8 ± 7.3%, and -2.1 ± 5.7%, respectively.

CONCLUSIONS

Our optimization workflow obtained using DoE for various field configurations provided the same or slightly superior plan quality compared with that created by experts. This process is feasible for clinical practice and will efficiently improve treatment quality while removing the influence of the planner's experience.

Automatic contrast medium extraction system using electron density data with dual-energy CT

OBJECTIVE:

The purpose of the current study is to create a contrast medium extraction method using raw-data-based electron density (rED) and CT number from dual-energy CT (DECT) for automatic delineation of the contrast region.

METHODS:

A CT-ED phantom containing tissue-equivalent inserts and an acrylic phantom with an iodinated contrast medium were scanned by DECT. The contrast medium extraction system was created using Python. The accuracy of the contrast medium extraction was evaluated by measuring the diameter in terms of the full width at half maximum (FWHM) and the ratio of the volume (ROV).

RESULTS:

Mean-2SD CT numbers and the difference of the CT numbers (DCT) of the contrast medium at 0-130 mg ml^-1 contrast medium concentration and the bone materials were more than -33 and -20 HU, respectively. In the correlation of rED and CT number, the gradient with the contrast medium phantom was greater than that with the CT-ED phantom. The accuracy of the contrast medium at 80 kV/135 kV and 100 kV/135 kV tube voltages. The gradient of the CT-ED and contrast medium phantoms were different. The gradient in the CT-ED phantom and the contrast medium was 0.0012 and 0.0003 at 80 kV/135 kV, and 0.0015 and 0.0005 at 100 kV/135 kV tube voltages, respectively. The ratio of the measured to the actual diameter in FWHM and ROV was 0.98-1.00 at 2-130 mg ml^-1. At a tube voltage of 100 kV/135 kV. The ratio of the measured to the actual diameter in ROV was 0.66 and FWHM was 0.90 at 2 mg ml^-1 contrast medium concentration. The ratio of the measured to the actual diameter in FWHM and ROV was 0.98-1.00 at 3-130 mg ml^-1.

CONCLUSION:

We created the contrast medium extraction method with rED and CT number images. The contrast medium extraction method could be used with DECT images at 80 kV/135 kV. The method is expected to only extract images from the region containing the contrast medium.

ADVANCES IN KNOWLEDGE:

We created the contrast medium extraction method using raw-data-based electron density and CT number from DECT and it is expected to only extract information from the region containing the contrast medium.

Excitation of the Isovector Spin Monopole Resonance via the Exothermic ^{90}Zr(^{12}N,^{12}C) Reaction at 175 MeV/u

The (^{12}N, ^{12}C) charge-exchange reaction at 175  MeV/u was developed as a novel probe for studying the isovector spin giant monopole resonance (IVSMR), whose properties are important for better understanding the bulk properties of nuclei and asymmetric nuclear matter. This probe, now available through the production of ^{12}N as a secondary rare-isotope beam, is exothermic, is strongly absorbed at the surface of the target nucleus, and provides selectivity for spin-transfer excitations. All three properties enhance the excitation of the IVSMR compared to other, primarily light-ion, probes, which have been used to study the IVSMR thus far. The ^{90}Zr(^{12}N,^{12}C) reaction was measured and the excitation energy spectra up to about 70 MeV for both the spin-transfer and non-spin-transfer channels were deduced separately by tagging the decay by γ emission from the ^{12}C ejectile. Besides the well-known Gamow-Teller and isobaric analog transitions, a clear signature of the IVSMR was identified. By comparing with the results from light-ion reactions on the same target nucleus and theoretical predictions, the suitability of this new probe for studying the IVSMR was confirmed.

Spectroscopy of Pionic Atoms in ^{122}Sn(d,^{3}He) Reaction and Angular Dependence of the Formation Cross Sections

We observed the atomic 1s and 2p states of π^{-} bound to ^{121}Sn nuclei as distinct peak structures in the missing mass spectra of the ^{122}Sn(d,^{3}He) nuclear reaction. A very intense deuteron beam and a spectrometer with a large angular acceptance let us achieve a potential of discovery, which includes the capability of determining the angle-dependent cross sections with high statistics. The 2p state in a Sn nucleus was observed for the first time. The binding energies and widths of the pionic states are determined and found to be consistent with previous experimental results of other Sn isotopes. The spectrum is measured at finite reaction angles for the first time. The formation cross sections at the reaction angles between 0° and 2° are determined. The observed reaction-angle dependence of each state is reproduced by theoretical calculations. However, the quantitative comparison with our high-precision data reveals a significant discrepancy between the measured and calculated formation cross sections of the pionic 1s state.

Tolerance levels of CT number to electron density table for photon beam in radiotherapy treatment planning system

The accuracy of computed tomography number to electron density (CT-ED) calibration is a key component for dose calculations in an inhomogeneous medium. In a previous work, it was shown that the tolerance levels of CT-ED calibration became stricter with an increase in tissue thickness and decrease in the effective energy of a photon beam. For the last decade, a low effective energy photon beam (e.g., flattening-filter-free (FFF)) has been used in clinical sites. However, its tolerance level has not been established yet. We established a relative electron density (ED) tolerance level for each tissue type with an FFF beam. The tolerance levels were calculated using the tissue maximum ratio (TMR) and each corresponding maximum tissue thickness. To determine the relative ED tolerance level, TMR data from a Varian accelerator and the adult reference computational phantom data in the International Commission on Radiological Protection publication 110 (ICRP-110 phantom) were used in this study. The 52 tissue components of the ICRP-110 phantom were classified by mass density as five tissues groups including lung, adipose/muscle, cartilage/spongy-bone, cortical bone, and tooth tissue. In addition, the relative ED tolerance level of each tissue group was calculated when the relative dose error to local dose reached 2%. The relative ED tolerances of a 6 MVFFF beam for lung, adipose/muscle, and cartilage/spongy-bone were ±0.044, ±0.022, and ±0.044, respectively. The thicknesses of the cortical bone and tooth groups were too small to define the tolerance levels. Because the tolerance levels of CT-ED calibration are stricter with a decrease in the effective energy of the photon beam, the tolerance levels are determined by the lowest effective energy in useable beams for radiotherapy treatment planning systems.

[Study of Dose Recalculation Method on Overriding Lung Density Using CBCT Image in the Thorax]

It is a useful method for the adaptive radiotherapy (ART) to calculate absorbed dose accurately on the image set taken by on-board cone beam computed tomography (CBCT) attached to linac for image-guided radiation therapy (IGRT). For this purpose, a simple and accurate calculation method is necessary. Several papers report that it is possible to calculate easily and accurately by using several methods of researches in the neck and prostate, but the lung density varies greatly depending on patient thorax condition. In this study, we propose a new dose recalculation method, which is a simple procedure and can achieve accurate dose calculation considered different lung densities in each patient. By using this method, it is possible to calculate exclusive of artifacts in CBCT because of overriding the lung density. The dose error between dose recalculation of the CBCT image and treatment plan agreed within±1%. Therefore, this method is expected to be a useful method for accurate dose calculation with CBCT image for ART.

Test of the Brink-Axel Hypothesis for the Pygmy Dipole Resonance

The gamma strength function and level density of 1^{-} states in ^{96}Mo have been extracted from a high-resolution study of the (p[over →], p[over →]^{'}) reaction at 295 MeV and extreme forward angles. By comparison with compound nucleus γ decay experiments, this allows a test of the generalized Brink-Axel hypothesis in the energy region of the pygmy dipole resonance. The Brink-Axel hypothesis is commonly assumed in astrophysical reaction network calculations and states that the gamma strength function in nuclei is independent of the structure of the initial and final state. The present results validate the Brink-Axel hypothesis for ^{96}Mo and provide independent confirmation of the methods used to separate gamma strength function and level density in γ decay experiments.

Tumor-Associated Macrophages in the Development of 4-Nitroquinoline-1-Oxide-Induced Tongue Squamous Cell Carcinoma in a Mouse Model

OBJECTIVE

We aimed to determine the distribution of tumor-associated macrophages (TAMs) in the development of tongue squamous cell carcinoma (SCC) and to elucidate the role of TAMs in the progression of tongue SCC.

METHODS

The expression of the macrophage markers nitric oxide synthase, Retnla, and mannose receptor 1 in the development of tongue SCC was longitudinally observed using real-time quantitative polymerase chain reaction. Additionally, an immunohistochemical study using an anti-mannose receptor (MR) antibody was performed.

RESULTS

The numbers of both of M1 and M2 macrophages in the tongues of mice treated with 4-nitroquinoline-1-oxide (4NQO) were significantly lower compared with those of normal tongues. The cyclooxygenase-2 (COX-2) inhibitor did not prevent cancer progression and did not affect the total number of macrophages in the tongues of 4NQO-treated mice. In the immunohistochemical studies, MR staining was observed in lymphangioendothelium in the subepithelial area of the tongues. The staining intensity of the MR was significantly stronger in the 4NQO-treated mice compared with that in control mice and 4NQO-treated mice treated with the COX-2 inhibitor.

CONCLUSION

TAMs may not contribute to the development of 4NQO-induced tongue SCC. MR expression is associated with the progression of 4NQO-induced tongue SCC.