A technique to quantify very low activities in regions of interest with a collimatorless detector

We present a new method to measure sub-microcurie activities of photon-emitting radionuclides in organs and lesions of small animals in vivo. Our technique, named the collimator-less likelihood fit, combines a very high sensitivity collimatorless detector with a Monte Carlo-based likelihood fit in order to estimate the activities in previously segmented regions of interest along with their uncertainties. This is done directly from the photon projections in our collimatorless detector and from the region of interest segmentation provided by an x-ray computed tomography scan. We have extensively validated our approach with 225Ac experimentally in spherical phantoms and mouse phantoms, and also numerically with simulations of a realistic mouse anatomy. Our method yields statistically unbiased results with uncertainties smaller than 20% for activities as low as ~111 Bq (3 nCi) and for exposures under 30 minutes. We demonstrate that our method yields more robust recovery coefficients when compared to SPECT imaging with a commercial pre-clinical scanner, specially at very low activities. Thus, our technique is complementary to traditional SPECT/CT imaging since it provides a more accurate and precise organ and tumor dosimetry, with a more limited spatial information. Finally, our technique is specially significant in extremely low-activity scenarios when SPECT/CT imaging is simply not viable.

Recent Progress in Diatom Biosilica: A Natural Nanoporous Silica Material as Sustained Release Carrier

A drug delivery system (DDS) is a useful technology that efficiently delivers a target drug to a patient's specific diseased tissue with minimal side effects. DDS is a convergence of several areas of study, comprising pharmacy, medicine, biotechnology, and chemistry fields. In the traditional pharmacological concept, developing drugs for disease treatment has been the primary research field of pharmacology. The significance of DDS in delivering drugs with optimal formulation to target areas to increase bioavailability and minimize side effects has been recently highlighted. In addition, since the burst release found in various DDS platforms can reduce drug delivery efficiency due to unpredictable drug loss, many recent DDS studies have focused on developing carriers with a sustained release. Among various drug carriers, mesoporous silica DDS (MS-DDS) is applied to various drug administration routes, based on its sustained releases, nanosized porous structures, and excellent solubility for poorly soluble drugs. However, the synthesized MS-DDS has caused complications such as toxicity in the body, long-term accumulation, and poor excretion ability owing to acid treatment-centered manufacturing methods. Therefore, biosilica obtained from diatoms, as a natural MS-DDS, has recently emerged as an alternative to synthesized MS-DDS. This natural silica carrier is an optimal DDS platform because culturing diatoms is easy, and the silica can be separated from diatoms using a simple treatment. In this review, we discuss the manufacturing methods and applications to various disease models based on the advantages of biosilica.

Dosimetry Reconstruction in Radiopharmaceutical Therapy Using a Sparse Network of External γ-Sensors

PURPOSE/OBJECTIVE(S)

Radiopharmaceutical therapy (RPT) has demonstrated promise in the treatment of neuroendocrine and prostate cancer. Due to the highly varied biodistribution and non-homogeneity of total integrated dose across cancer patients, a system for real-time dosimetry based on continuous measurement is desirable to deliver sufficient dose for tumor ablation while preventing toxicity from off-target uptake by organs at risk (OAR). Single time point imaging (mostly SPECT)-based dosimetry offers a snapshot of the body-wide dose distribution at a given time point, but even single SPECT imaging is generally limited in availability, often leading to significant inaccuracies in estimating total integrated dose. Therefore, accurate personalized dosimetry in RPT is an unmet need and requires continuous dosimetry measurements of tumors and OARs across multiple half-lives of the therapeutic radiopharmaceutical. Using a priori knowledge of tumor and OAR locations from pretherapy imaging, we have developed a novel algorithm that utilizes a network of custom uncollimated, optical fiber-based γ-counting probes to isolate the real-time in vivo tumor and OAR uptake in 177Lu-PSMA-617 and 225Ac-MACROPA-YS5 therapy.

MATERIALS/METHODS

The proposed system was successfully validated in athymic mice models bearing varying numbers of tumors from two human prostate cancer cell lines (PC3-pip, PC3-flu). Uncollimated γ counts using the developed probes were acquired outside of the mice for 10 minutes, starting at 0 hr, 6 hrs, 12 hrs, 24 hrs, and 48 hrs after the injection of 177Lu-PSMA-617. The percent injected activity per mL of tissue (%IA/mL) of each tumor and OAR was reconstructed at every time point and compared to the %IA/mL extracted from SPECT/CT immediately after the recording.

RESULTS

The developed system's %IA/mL reconstruction in PC3-pip tumors, PC3-flu tumors, kidneys, and bladders is highly correlative with the %IA/mL extracted from state-of-art in vivo dosimetry techniques, with %IA/mL ranging from 0.1% to 160% assuming a 29.6 MBq 177Lu-PSMA-617 administration. The least squares linear regression fit between the reconstructed activity and the activity measured from SPECT/CT is given by Estimated %IA/mL = 0.91 x SPECT %IA/mL, with an R2 of 0.991, and Pearson's r of 0.9975. There is a nearly 1:1 mapping between the proposed model and SPECT/CT.

CONCLUSION

A novel dose reconstruction algorithm for personalized dosimetry in RPT that utilizes a sparse set of external γ-counters and a priori knowledge of tumor and OAR locations was developed and validated in in vivo human prostate cancer murine models. The proposed system enables continuous dosimetry measurements of multiple tumors and OAR noninvasively, with high accessibility, high temporal resolution, and across multiple classes of ɑ and β-based RPT. Similar experiments using 225Ac-MACROPA-YS5 are ongoing and additional results will be reported.

Fabrication of graphene oxide-based pretreatment filter and Electrochemical-CRISPR biosensor for the field-ready cyanobacteria monitoring system

Microcystis aeruginosa (M. aeruginosa) cause the eutrophication of lakes and rivers. To effectively control the overgrowth of M. aeruginosa, a suitable measurement method should be required in the aquatic fields. To address this, we developed a field-ready cyanobacterial pretreatment device and an electrochemical clustered regularly interspaced short palindromic repeats (EC-CRISPR) biosensor. The cyanobacterial pretreatment device consists of a syringe, glass bead, and graphene oxide (GO) bead. Then, the M. aeruginosa dissolved in the freshwater sample was added to fabricated filter. After filtration, the purified gene was loaded onto a CRISPR-based electrochemical biosensor chip to detect M. aeruginosa gene fragments. The biosensor was composed of CRISPR/Cpf1 protein conjugated with MXene on an Au microgap electrode (AuMGE) integrated into a printed circuit board (PCB). This AuMGE/PCB system maximizes the signal-to-noise ratio, which controls the working and counter electrode areas requiring only 3 μL samples to obtain high reliability. Using the extracted M. aeruginosa gene with a pre-treatment filter, the CRISPR biosensor showed a limit of detection of 0.089 pg/μl in fresh water. Moreover, selectivity test and matrix condition test carried out using the EC-CRISPR biosensor. These handheld pre-treatment kit and biosensors can enable field-ready detection of CyanoHABs.

Recent Progress of Lipid Nanoparticles-Based Lipophilic Drug Delivery: Focus on Surface Modifications

Numerous drugs have emerged to treat various diseases, such as COVID-19, cancer, and protect human health. Approximately 40% of them are lipophilic and are used for treating diseases through various delivery routes, including skin absorption, oral administration, and injection. However, as lipophilic drugs have a low solubility in the human body, drug delivery systems (DDSs) are being actively developed to increase drug bioavailability. Liposomes, micro-sponges, and polymer-based nanoparticles have been proposed as DDS carriers for lipophilic drugs. However, their instability, cytotoxicity, and lack of targeting ability limit their commercialization. Lipid nanoparticles (LNPs) have fewer side effects, excellent biocompatibility, and high physical stability. LNPs are considered efficient vehicles of lipophilic drugs owing to their lipid-based internal structure. In addition, recent LNP studies suggest that the bioavailability of LNP can be increased through surface modifications, such as PEGylation, chitosan, and surfactant protein coating. Thus, their combinations have an abundant utilization potential in the fields of DDSs for carrying lipophilic drugs. In this review, the functions and efficiencies of various types of LNPs and surface modifications developed to optimize lipophilic drug delivery are discussed.

Rapid electrochemical biosensor composed of DNA probe/iridium nanoparticle bilayer for Aphanizomenon flos-aquae detection in fresh water

Toxic cyanobacteria pose a serious threat to aquatic ecosystems and require adequate detection and control systems. Aphanizomenon flos-aquae is a harmful cyanobacterium that produces the toxicant saxitoxin. Therefore, it is necessary to detect the presence of A. flos-aquae in lakes and rivers. We proposed a rapid electrochemical biosensor composed of DNA primer/iridium nanoparticles (IrNP) bilyer for the detection of A. flos-aquae in freshwater. The extracted A. flos-aquae gene (rbcL-rbcX) is used as a target, and it was fixed to the electrode using a 5'-thiolated DNA primer (capture probe). Then, Avidin@IrNPs complex for amplification of electrical signals was bound to the target through a 3'-biotinylated DNA primer (detection probe). To rapidly detect the target, an alternating current electrothermal flow technique was introduced in the detection step, which could reduce the detection time to within 20 min. To confirm the biosensor fabrication, atomic force microscopy was used to investigate the surface morphology. To evaluate the biosensor performance, cyclic voltammetry and electrochemical impedance spectroscopy were used. The target gene was detected at a concentration of 9.99 pg/mL in tap water, and the detection range was 0.1 ng/mL to 10³ ng/mL with high selectivity. Based on the combined system, we employed A. flos-aquae in tap water. This rapid cyanobacteria detection system is a powerful tool for CyanoHABs in the field.

Improving Biosensors by the Use of Different Nanomaterials: Case Study with Microcystins as Target Analytes

The eutrophication of lakes and rivers without adequate rainfall leads to excessive growth of cyanobacterial harmful algal blooms (CyanoHABs) that produce toxicants, green tides, and unpleasant odors. The rapid growth of CyanoHABs owing to global warming, climate change, and the development of rainforests and dams without considering the environmental concern towards lakes and rivers is a serious issue. Humans and livestock consuming the toxicant-contaminated water that originated from CyanoHABs suffer severe health problems. Among the various toxicants produced by CyanoHABs, microcystins (MCs) are the most harmful. Excess accumulation of MC within living organisms can result in liver failure and hepatocirrhosis, eventually leading to death. Therefore, it is essential to precisely detect MCs in water samples. To date, the liquid chromatography-mass spectrometry (LC-MS) and enzyme-linked immunosorbent assay (ELISA) have been the standard methods for the detection of MC and provide precise results with high reliability. However, these methods require heavy instruments and complicated operation steps that could hamper the portability and field-readiness of the detection system. Therefore, in order for this goal to be achieved, the biosensor has been attracted to a powerful alternative for MC detection. Thus far, several types of MC biosensor have been proposed to detect MC in freshwater sample. The introduction of material is a useful option in order to improve the biosensor performance and construct new types of biosensors. Introducing nanomaterials to the biosensor interface provides new phenomena or enhances the sensitivity. In recent times, different types of nanomaterials, such as metallic, carbon-based, and transition metal dichalcogenide-based nanomaterials, have been developed and used to fabricate biosensors for MC detection. This study reviews the recent advancements in different nanomaterial-based MC biosensors.

Evaluation of the complete nuclear rDNA unit sequence of the jellyfish Cyanea nozakii Kishinouye (Scyphozoa: Semaeostomeae) for molecular discrimination

The harmful jellyfish Cyanea nozakii Kishinouye has frequently occurred on Korean coasts, and its blooms have caused serious ecological and economic damages. DNA sequences of the C. nozakii for molecular detection and discrimination are relatively scarce. In this study, we determined the complete sequence of a single unit of tandemly repeated ribosomal DNA (rDNA) of the Korean C. nozakii and characterized the molecular features of the rDNA. The complete rDNA contained 8,003 bp (48.4% GC) with the same gene arrangement (18S, ITS1, 5.8S, ITS2, 28S, and IGS) to the typical eukaryotes. Dot plot analysis showed that the coding regions (18S, 5.8S, and 28S) were highly conserved, while the non-coding regions (ITS1, ITS2, and IGS) were more variable and parsimony-informative. The IGS contained a putative transcription termination signal (poly(T) tract) and four repeats of block minisatellites. Phylogenetic analyses using 18S and 28S rDNA revealed well-resolved relationships of C. nozakii within the order Semaeostomeae, separating it from other Cyanea species. The complete rDNA sequence provides various options for the selection of jellyfish taxonomic markers and may be useful for discriminating between species of C. nozakii and phylogeny reconstruction with close relatives.

The complete mitochondrial genome of the hydrozoan jellyfish Turritopsis lata Lendenfeld, 1885 (Cnidaria; Hydrozoa; Anthoathecata) with molecular phylogenetic analysis

In this study, we sequenced and analyzed the complete mitochondrial genome (mtgenome) of the hydrozoan jellyfish Turritopsis lata. The mtgenome was a complete linear form (15,047 bp in length, 30.9% A, 42.1% T, 12.5% C, and 14.5% G), including 13 protein coding genes (PCGs) (cox1, cox2, cox3, atp6, atp8, nad1, nad2, nad3, nad4, nad4L, nad5, nad6, and cytb), 2 tRNAs (tRNAMet and tRNATrp), and 2 rRNAs (12S and 16S rRNA). The genome structure of the T. lata was completely identical to those of other species within the subclass Hydroidolina. In addition, our molecular phylogenetic analysis using 13 PCGs within hydrozoans showed that T. lata was the closest to Turritopsis dohrnii.

Fermented milk with Lactobacillus curvatus SMFM2016-NK alleviates periodontal and gut inflammation, and alters oral and gut microbiota

This study aimed to analyze the effect of milk fermented with Lactobacillus curvatus SMFM2016-NK on periodontal diseases and gut health in a rat model. To improve the effect of Lb. curvatus SMFM2016-NK-fermented milk administration for relieving periodontitis, the periodontitis rat models were treated with the following for 4 wk: 10% skim milk (normal), periodontitis + 10% skim milk (negative control), periodontitis + Lactobacillus rhamnosus GG-fermented milk (positive control), and periodontitis + Lb. curvatus SMFM2016-NK-fermented milk (PD+LCFM). Transcriptional analysis of inflammatory cytokines [tumor necrosis factor α (TNF-α), IL-1β, IL-6, and IL-10] was performed via quantitative reverse-transcription PCR. The changes in the oral and gut microbiomes after administering Lb. curvatus SMFM2016-NK-fermented milk were analyzed with metagenomics sequencing using DNA extracted from the oral gingival tissues and feces from the cecum of the rat models. After treatment with Lb. curvatus SMFM2016-NK-fermented milk, the relative gene expression levels of TNFA and IL1B in the gingiva decreased in the PD+LCFM group compared with those in the negative control group. In the oral microbiome, the proportion of the phylum Proteobacteria in the PD+LCFM group was lower than that in the negative control after treatment with Lb. curvatus SMFM2016-NK-fermented milk. For the effect in the gut, the relative gene expression levels of inflammatory cytokines in the colon between the normal and negative control groups were not different; however, the expression levels of TNFA and IL1B in the PD+LCFM and positive control groups, respectively, were lower than those in the negative control group. The composition and diversity of the gut microbiome differed among normal, periodontitis, and Lb. curvatus SMFM2016-NK-fermented milk treatment groups. These results indicate that Lb. curvatus SMFM2016-NK-fermented milk could alleviate periodontal and gut inflammation and change oral and gut microbiota.

Subepithelial neutrophil infiltration as a predictor of the surgical outcome of chronic rhinosinusitis with nasal polyps

BACKGROUND

Neutrophils present as major inflammatory cells in refractory chronic rhinosinusitis with nasal polyps (CRSwNP), regardless of the endotype. However, their role in the pathophysiology of CRSwNP remains poorly understood. We investigated factors predicting the surgical outcomes of CRSwNP patients with focus on neutrophilic localization.

METHODS

We employed machine-learning methods such as the decision tree and random forest models to predict the surgical outcomes of CRSwNP. Immunofluorescence analysis was conducted to detect human neutrophil elastase (HNE), Bcl-2, and Ki-67 in NP tissues. We counted the immunofluorescence-positive cells and divided them into three groups based on the infiltrated area, namely, epithelial, subepithelial, and perivascular groups.

RESULTS

On machine learning, the decision tree algorithm demonstrated that the number of subepithelial HNE-positive cells, Lund-Mackay (LM) scores, and endotype (eosinophilic or non-eosinophilic) were the most important predictors of surgical outcomes in CRSwNP patients. Additionally, the random forest algorithm showed that, after ranking the mean decrease in the Gini index or the accuracy of each factor, the top three ranking factors associated with surgical outcomes were the LM score, age, and number of subepithelial HNE-positive cells. In terms of cellular proliferation, immunofluorescence analysis revealed that Ki-67/HNE-double positive and Bcl-2/HNE-double positive cells were significantly increased in the subepithelial area in refractory CRSwNP.

CONCLUSION

Our machine-learning approach and immunofluorescence analysis demonstrated that subepithelial neutrophils in NP tissues had a high expression of Ki-67 and could serve as a cellular biomarker for predicting surgical outcomes in CRSwNP patients.

Complete mitochondrial genome of the hydrozoan jellyfish Blackfordia virginica Mayer, 1910 (Cnidaria; Hydrozoa; Leptothecata) with phylogenetic analysis

In this study, we analyzed the complete mitochondrial genome of the hydrozoan jellyfish Blackfordia virginica. The genome was a linear form (15,109 bp long, 73.6% AT), including 13 protein-coding genes (cox2, atp8, atp6, cox3, nad2, nad5, nad6, nad3, nad4L, nad1, nad4, cytB, and cox1), 2 tRNAs (tRNA-Met and tRNA-Trp), and 2 rRNAs (12S and 16S RNA). The genome structure of the B. virginica was completely identical to mitochondrial genomes of other hydrozoans that belonged to Leptothecata and Anthoathecata. Molecular phylogenetic analysis within hydrozoan species showed that B. virginica was the closest to the hydrozoan Laomedea flexuosa.

Engineered ionizable lipid nanoparticles for targeted delivery of RNA therapeutics into different types of cells in the liver

Ionizable lipid nanoparticles (LNPs) have been widely used for in vivo delivery of RNA therapeutics into the liver. However, a main challenge remains to develop LNP formulations for selective delivery of RNA into certain types of liver cells, such as hepatocytes and liver sinusoidal endothelial cells (LSECs). Here, we report the engineered LNPs for the targeted delivery of RNA into hepatocytes and LSECs. The effects of particle size and polyethylene glycol-lipid content in the LNPs were evaluated for the hepatocyte-specific delivery of mRNA by ApoE-mediated cellular uptake through low-density lipoprotein receptors. Targeted delivery of RNA to LSECs was further investigated using active ligands. Incorporation of mannose allowed the selective delivery of RNA to LSECs, while minimizing the unwanted cellular uptake by hepatocytes. These results demonstrate that engineered LNPs have great potential for the cell type-specific delivery of RNA into the liver and other tissues.

Clinical features, risk factors, and prognosis of anthracycline-induced cardiotoxicity in patients with malignant lymphoma who received a CHOP like regimen

Background

Anthracycline-induced cardiotoxicity is a serious complication in patients with malignant lymphoma (ML) who received chemotherapy, which threatens life prognosis and quality of life of patients. However, incidence and risk factors of cardiotoxicity in patients with ML who undergo intensive chemotherapy which aims complete remission is not clarified. Furthermore, prognosis after cardiotoxicity and that after recovery from cardiotoxicity have not been elucidated.

Method

We screened 443 ML patients who received either rituximab (R)-CHOP or CHOP regimen between January 2008 and December 2017 at Nagoya City University Hospital. Two handled forty-four patients who underwent echocardiography before and after chemotherapy were enrolled and data were analyzed retrospectively. Cardiotoxicity was defined as a decline in left ventricular ejection fraction (LVEF) of 10% or greater and an LVEF was below 50%. Partial recovery was defined as a 5% or more of increase in LVEF and an LVEF was ≥50% after cardiotoxicity. Complete recovery was defined as an increase in LVEF became more than 95% of the baseline value. Patient's basic characteristics, chemotherapeutic regimen, laboratory data, echocardiographic data, and prognosis were collected from the medical records by two cardiologists and two hematologists.

Result

At baseline, the median age was 71 years, the median cumulative dose of doxorubicin was 302 mg/m2 and the median LVEF was 69%. During the follow-up period, cardiotoxicity was observed in 52 out of 244 patients (21%), 30 patients (12%) had a symptomatic heart failure, and 5 patients died from cardiovascular cause. Thirty-five patients developed cardiotoxicity during the first year of chemotherapy. Multivariate analysis identified that only the baseline LVEF (HR 0.949, 95% CI 0.919–0.981, p=0.002) was an independent risk factor for cardiotoxicity. In our study, patients who received more than 200 mg/m2 of doxorubicin developed cardiotoxicity frequently. Among 52 patients who experienced cardiotoxicity, partial recovery and full recovery were observed in 18 (35%) and 4 (8%) patients, respectively. Four patients without recovery died due to heart failure and 1 patient with partial recovery died suddenly. Six out of 18 patients with partial recovery developed re-cardiotoxicity.

Conclusion

ML patients who undergo more than 200 mg/m2 of doxorubicin need a watchful follow-up. Only a baseline LVEF was an independent risk factor for cardiotoxicity. one third of patients with partial recovery developed re-cardiotoxicity.

Funding Acknowledgement

Type of funding source: None

Diagnostic accuracy of left ventricular diastolic transverse strain imaging by speckle tracking echocardiography for diagnosing chest pain in diabetic patients

Background

Two-dimensional speckle tracking echocardiography (2D-STE) has been reported to be useful for the diagnosis of myocardial ischemia by detecting delayed relaxation (diastolic stunning) after an episode of angina. 2D-longitudinal strain is not specific besides ischemia such as diastolic dysfunction, and diabetes have been associated with abnormal longitudinal fibers. The aim is to evaluate the diagnostic accuracy of Left ventricular (LV) diastolic transverse strain imaging by STE to detect the presence of acute coronary syndrome (ACS) in diabetic patients with acute chest pain.

Methods

385 consecutive patients with acute chest pain and without wall motion abnormality, who were admitted to an emergency department (ED) at 1 of 12 clinical sites in Japan, were enrolled and underwent 2D-STE at ED. Left ventricular (LV) transverse strain values at aortic valve closure (A) and one-third of diastole duration (B) were measured. The strain imaging diastolic index (SI-DI) was value was determined as: (A − B)/A × 100% to assess the LV diastolic strain imaging and was used to identify the regional LV delayed relaxation. All patients underwent coronary CT or coronary angiography to establish the diagnosis of ACS. Clinicians were blinded to the 2D-STE results.

Results

Out of 385 patients, 2D-STE analysis was possible in 365 patients (94%). 76 patients were diabetic (DM+), and 289 patients were non-diabetic (DM-). With assessment of coronary CT or coronary angiography, ACS was diagnosed in 125 patients (34%). 2D-STE was obtained at a mean of 5.3 hours after chest pain episode. Transverse SI-DI of ischemic segments were significantly lower than those of non-ischemic segments (p value <0.001) in both diabetic and non-diabetic patients, and transverse SI-DI of both diabetic and non-diabetic patients demonstrated high area under curve (AUC) for detection of myocardial ischemia (Figure: RCA; right coronary artery, LAD; left anterior descending artery, LCX; left circumferencial artery). In diabetic patients, sensitivity, specificity, and negative predictive value for ACS of transverse SI-DI are 100%, 95%, 100% in RCA (a cut-off value of 36.2), and 86.4%, 95%, 93% in LAD (a cut-off value of 50.2), and 75%, 85%, 94% in LCX (a cut-off value of 52), respectively.

Conclusion

LV diastolic transverse strain imaging by 2D-STE at ED increase the sensitivity, specificity and accuracy to predict the presence of ACS in diabetic patients with chest pain, as well as non-diabetic patients. (UMIN000013859).

Figure 1. Transverse Strain (SI-DI): AUC (95% CI)

Funding Acknowledgement

Type of funding source: None

Arterial stiffness could reflect increased cardiac load and reduced pulmonary function in the general population

Background

Pulmonary function is known to decrease with age and reduced pulmonary function has been reported to be associated with all-cause mortality and cardiovascular death. The association between pulmonary impairment and atherosclerosis was reported previously but has not been investigated sufficiently in the general population.

Purpose

We hypothesized that arterial stiffness could reflect increase of cardiac load and reduced pulmonary function. The present study aimed to investigate whether increased cardiac load and reduced pulmonary function could affect arterial stiffness in the general population.

Methods

Subjects undergoing their health check-up were enrolled. Plasma B-type natriuretic peptide (BNP) levels and serum high-sensitivity cardiac troponin I (hs-cTnI) levels were measured to evaluate cardiac load and myocardial damage. Radial augmentation index (rAI) was measured to investigate arterial stiffness using HEM-9000AI device. Subjects with an ST-T segment abnormality on the electrocardiogram, renal insufficiency, cancer, active inflammatory disease, or a history of cardiovascular events and pulmonary disease were excluded. Pulmonary function was assessed using spirometry by calculating forced vital capacity (FVC) as a percentage of predicted value (FVC%-predicted), forced expiratory volume in 1 second (FEV1) as a percentage of predicted value (FEV1%-predicted), and the ratio of FEV1 to FVC (FEV1/FVC).

Results

A total of 1100 subjects aged 57 years were enrolled and their median values of BNP and hs-cTnI were 15.5 and 2.3 pg/ml. The levels of rAI were significantly associated with the levels of BNP after adjustment for possible confounders in multivariate regression analysis, but were not with the levels of hs-TnI. While the parameters of pulmonary function were inversely associated with the levels of rAI and hs-cTnI after adjustment for possible confounders in the multivariate regression analysis, but not with the levels of BNP. The other multivariate regression analyses where BNP, hs-cTnI, parameters of pulmonary function, and the other possible factors were simultaneously included as independent variables revealed that the BNP levels and the FVC%-predicted or FEV1%-predicted, besides age, gender, smoking status, body mass index, blood pressure, heart rate, creatinine, fasting plasma glucose, and triglyceride, were significantly associated with the levels of rAI.

Conclusions

The significant associations of rAI with BNP and pulmonary function were revealed in the general population. These findings support that arterial stiffness could reflect increased cardiac load and reduced pulmonary function, in apparently healthy individuals.

Funding Acknowledgement

Type of funding source: None

The complete mitochondrial genome of the hydrozoan jellyfish Spirocodon saltatrix (Cnidaria; Hydrozoa; Anthoathecata) with phylogeny analysis

In the present study, we sequenced and analyzed the complete mitochondrial genome of the hydrozoan jellyfish Spirocodon saltatrix. The mitochondrial genome was a linear form (15,752 bp long, 70.4% AT), consisting of 13 protein coding genes (cox1, cox2, atp8, atp6, cox3, nad2, nad5, nad6, nad3, nad4L, nad1, nad4, and cytB), two tRNAs (tRNA-Met and tRNA-Trp), and two rRNAs (12S and 16S). Mitochondrial gene arrangement of the S. saltatrix was completely identical to already-known mitochondrial genomes of hydrozoans. Molecular phylogenetic analysis using 13 protein-coding genes showed that S. saltatrix was closely related to the hydrozoan Clava multicornis.

P743 Right ventricular function is important for exercise capacity in patients at risk of heart failure

Background and Purpose

It is important to evaluate exercise capacity to detect the development of heart failure (HF) in patients with heart disease. The pathology of exercise capacity is multi-factorial, and cardiac function is recognized as one of the most important determinants. However, the correlation between right ventricular (RV) function and exercise capacity is not fully understood in the subjects without HF. Therefore, we assessed the relationship between RV function and exercise capacity, both in patients with HF (HF+) and in patients with heart disease but not developed HF (HF-).

Methods

Two hundred and fifty-two patients with heart disease who underwent both Doppler echocardiography at rest and cardio-pulmonary exercise testing (CPET) for the assessment of heart function were enrolled (HF+: n = 142, HF-: n = 110). We measured left ventricular ejection fraction (LVEF), peak early diastolic transmitral flow velocity (E), peak late diastolic transmitral flow velocity (A), early diastolic mitral annular velocity (e’), left atrial volume (LAV), and tricuspid annular plane systolic excursion (TAPSE) by echocardiography. After echocardiographic examination, symptom-limited exercise testing was performed with simultaneous respiratory gas analysis, and peak oxygen consumption (pVO2) was determined. Blood examination including hemoglobin (Hb) and brain natriuretic peptide (BNP) was done on the same day.

Results

There were significant relationships between pVO2 and LVEF (r = 0.16, p = 0.005), e" (r = 0.51, p < 0.0001), E/e" (r=-0.47, p < 0.0001), LAV (r=-0.21, p = 0.0002), and TAPSE (r = 0.33, p < 0.0001) in the whole subjects. In the multiple regression analyses, age, Hb, E/e" and TAPSE were selected as significant determinants for pVO2 both in HF+ (R²=0.39, p < 0.0001) and HF- (R²=0.33, p < 0.0001).

Conclusion

RV function is the prime determinant of exercise capacity in patients at risk of HF, as well as in patients with HF.

Abstract P743 Figure.

1225 Diagnostic accuracy of left ventricular diastolic strain imaging by speckle tracking echocardiography in detecting ischemic etiology of acute chest pain

Funding Acknowledgements

none

OnBehalf

A TRAC-SI Multicenter Trial

Background

Two-dimensional speckle tracking echocardiography (2D-STE) has been reported to be useful for the diagnosis of myocardial ischemia by detecting delay in regional myocardial expansion (diastolic stunning) up to many hours after an episode of angina. The aim is to evaluate the diagnostic accuracy of Left ventricular (LV) diastolic longitudinal, circumferential, transverse and radial strain imaging by STE to detect the presence of acute coronary syndrome (ACS) in patients with acute chest pain.

Methods

388 consecutive patients with acute chest pain and without wall motion abnormality, who were admitted to an emergency department (ED) at 1 of 12 clinical sites in Japan, were enrolled and underwent 2D-STE at ED. Left ventricular (LV) longitudinal, circumferential, transverse and radial strain values at aortic valve closure (A) and one-third of diastole duration (B) were measured. The strain imaging diastolic index (SI-DI) was value was determined as: (A-B)/A × 100% to assess the LV diastolic strain imaging and was used to identify the regional LV delayed relaxation. All patients underwent coronary CT or coronary angiography to establish the diagnosis of ACS. Clinicians were blinded to the 2D-STE results.

Results

Out of 388 patients, 2D-STE analysis was possible in 358 patients (92%). With assessment of coronary CT or coronary angiography, ACS was diagnosed in 118 patients (33%). 2D-STE was obtained at a mean of 5.3 hours after chest pain episode. SI-DI of longitudinal, circumferential, transverse and radial strain of ischemic segments were significantly lower than those of non-ischemic segments (p value < 0.001), and transverse and radial SI-DI demonstrated high diagnostic accuracy, compared with longitudinal SI-DI (Figure 1). Sensitivity, specificity, and negative predictive value for ACS of transverse SI-DI are 87%, 88%, % and 95%, respectively, using a cut-off value of 63.3.

Conclusion

LV diastolic strain imaging by 2D-STE at ED increase the sensitivity, specificity and accuracy to predict the presence of ACS in patients with chest pain. Compared with longitudinal diastolic strain imaging, transverse diastolic strain imaging is more sensitive marker to detect the myocardial ischemic episode (UMIN000013859).

Abstract 1225 Figure 1

A Case Series of Asymptomatic Hemodialysis Catheter-Related Right Atrial Thrombi That Are Incidentally Detected Prior to Kidney Transplantation

A hemodialysis (HD) catheter-related right atrial thrombus (RAT) is rarely encountered prior to kidney transplantation (KT) but necessitates a decision about whether to anticoagulate and/or delay the surgery. There is controversy surrounding the clinical implications of a RAT in this situation. It is sometimes considered fatal but other opinions consider it to be benign, especially when incidentally detected. We reviewed the clinical characteristics, management, and outcomes of a patient series with HD catheter-related RAT detected prior to KT and speculated on its clinical significance. Among 3677 cases of KT performed on 3607 patients between January 1997 and September 2015 in our single tertiary center, 11 cases of HD catheter-related RAT detected on transthoracic echocardiography (TTE) prior to KT were included for analysis. The average maximal diameter of the RAT was 23.2 ± 16.3 (SD in mm) and 9 (81.8%) of these 11 patients had no symptoms associated with the RAT. Four patients (36.3%) had their catheters replaced, 5 patients (45.5%) had their catheters removed, and the catheters were maintained in the remaining 2 patients (18.2%). Six patients (54.5%) were anticoagulated with either heparin or warfarin. However all 11 patients had a successful KT suggesting that a HD catheter-related RAT incidentally detected prior to this surgery may not be as serious as previously considered and should not be a reason for delaying the transplantation.

Comprehensive Analysis of the Jellyfish Chrysaora pacifica (Goette, 1886) (Semaeostomeae: Pelagiidae) with Description of the Complete rDNA Sequence

Jinho Chae, Yoseph Seo, Won Bae Yu, Won Duk Yoon, Hye Eun Lee, Soo-Jung Chang, and Jang-Seu Ki (2018) The Scyphomedusae genus Chrysaora consists of highly diversified jellyfishes. Although morphological systematics of the genus has been documented over the past century, characterization of molecular taxonomy has been attempted only recently. In the present study, we sequenced an 8,167 bp region, encompassing a single ribosomal DNA (rDNA) repeat unit, from Chrysaora pacifica, and used it for phylogenetic analyses. The tandemly repeated rDNA units turned out to consist of both coding and noncoding regions, whose arrangement was found to be the same as that of a typical eukaryote. None of the 5S rRNA sequences were found among the repeat units. Comparative analyses of jellyfish rDNA sequences showed that the 28S locus is highly informative and divergent compared to the 18S locus. Phylogenetic analyses of the 18S and 28S loci revealed that the Semaeostomeae order of jellyfish is separated into taxonomic groups by families and genera, with a few exceptions. The family Pelagiidae was in a clade separate from other groups, thus forming a monophyletic lineage. All Chrysaora included here formed a strongly supported clade within the family Pelagiidae, and Pelagiidae manifested a sister relationship with Cyanea. Nonetheless, Chrysaora was found to be paraphyletic in both 18S and 28S phylogenies. Chrysaora pacifica was clearly distinct from close relatives C. melanaster and C. quinquecirrha. These results provide a special reference for the DNA taxonomy of Pelagiidae jellyfishes in terms of nuclear cistron rDNA sequences and improve our understanding of the molecular phylogenetic relationships among Semaeostomeae jellyfishes.

The complete mitogenome of ghost jellyfish Cyanea nozakii (Cnidaria, Semaeostomeae, Cyaneidae)

The cnidarian jellyfishes are impressive organisms to show animal mitochondrial genomic diversities. Their mitogenome structure is linear and tRNA content has one or two in numbers, which is highly different than other metazoans. In this study, a complete mitogenome of the ghost jellyfish Cyanea nozakii (Cnidaria, Semaeostomeae, Cyaneidae) was sequenced and analyzed. The mitgenome is 17,381 bp long with 38.5% A, 16.0% C, 13.9% G, and 31.6% T nucleotide distributions. In addition, phylogenetic relationship of C. nozakii in the class Scyphozoa was investigated by using mitochondrial protein coding genes. Due to results, C. nozakii was positioned in the paraphyletic order Semaeostomeae. This is the first complete mitogenome from the genus Cyanea.

Effect of topical loteprednol etabonate with lid hygiene on tear cytokines and meibomian gland dysfunction in prosthetic eye wearers

PurposeTo assess tear cytokine levels and clinical outcomes in meibomian gland dysfunction (MGD) in the blind eye of patients wearing an ocular prosthesis after 2 months of treatment with topical loteprednol etabonate and eyelid scrubs with warm compresses.Patients and methodsThis study included patients with MGD wearing a unilateral ocular prosthesis for more than 1 year. All patients topically received 0.5% loteprednol etabonate and were instructed to scrub their eyelids with warm compresses on the prosthetic eye for 2 months. We evaluated tear cytokine levels using Multiplex Bead Immunoassays, performed biomicroscopic examination of the lid margins and meibomian gland, conducted meibography imaging, and assessed MGD-related ocular symptoms using a questionnaire for the prosthetic eye before and 2 months after treatment.ResultsThirty consecutive patients were included. There were significant reductions in the levels of interleukin (IL)-6, interferon-γ, monocyte chemotactic protein-1, IL-8, tumor necrosis factor-α, and IL-1β (P<0.001 for each cytokine). Moreover, there were improvements in ocular symptoms (P=0.001), lid margin abnormalities (P<0.001), meibomian gland expressibility (P<0.001) and meibography findings (P=0.037).ConclusionTopical loteprednol etabonate in conjunction with eyelid scrubs and warm compresses were effective in treating MGD in prosthetic eye wearers. Furthermore, tear cytokine measurements may serve as an additional approach for evaluating the efficacy of anti-inflammatory treatment for MGD in prosthetic eye wearers.

Unsupervised Learning in PET Radiomics

In this study, we investigated large scale radoimics on 116 breast cancer patients. We are particularly interested in unsupervised learning to bicluster patients and features in order to associate such biclusters with the disease characteristics. The results show that radiomics features with wavelet features have a better biclustering ability. And 172 radiomics features have shown a better classification capability.

[18F]-Sodium Fluoride PET MR-Based Localization and Quantification of Bone Turnover as a Biomarker for Facet Joint-Induced Disability

Our aim was to prospectively evaluate the relationship between low back pain-related disability and quantitative measures from [¹⁸F]-sodium fluoride ([¹⁸F]-NaF) MR imaging. Six patients with facetogenic low back pain underwent dynamic [¹⁸F]-NaF PET/MR imaging. PET metrics were correlated with clinical measures and MR imaging grading of lumbar facet arthropathy. A significant positive correlation was observed between maximum facet joint uptake rate and clinical disability (P < .05). These data suggest that dynamic [¹⁸F]-NaF PET may serve as a useful biomarker for facetogenic disability.

Test of a 32-channel Prototype ASIC for Photon Counting Application

A new low-power application-specific integrated circuit (ASIC) for Cadmium Zinc Telluride (CZT) detectors for single-photon emission computed tomography (SPECT) application is being developed at BNL. As the first step, a 32-channel prototype ASIC was designed and tested recently. Each channel has a preamplifier followed by CR-RC³ shaping circuits and three independent energy bins with comparators and 16-bit counters. The ASIC was fabricated with TSMC 0.35-μm complementary metal-oxide-semiconductor (CMOS) process and tested in laboratories. The power consumption is around 1 mW/ch with a 2.5-V supply. With a gain of 400 mV/fC and the peaking time of 500 ns, the equivalent noise charge (ENC) of 360 e- has been measured in room temperature while the crosstalk rate is less than 0.3%. The 10-bit DACs for global thresholds have an integral nonlinearity (INL) less than 0.56% and differential nonlinearity (DNL) less than 0.33%. In the presentation, we will report the detailed test results with this ASIC.