Functional ultrasound imaging of the human spinal cord

Utilizing the first in-human functional ultrasound imaging (fUSI) of the spinal cord, we demonstrate the integration of spinal functional responses to electrical stimulation. We record and characterize the hemodynamic responses of the spinal cord to a neuromodulatory intervention commonly used for treating pain and increasingly used for the restoration of sensorimotor and autonomic function. We found that the hemodynamic response to stimulation reflects a spatiotemporal modulation of the spinal cord circuitry not previously recognized. Our analytical capability offers a mechanism to assess blood flow changes with a new level of spatial and temporal precision in vivo and demonstrates that fUSI can decode the functional state of spinal networks in a single trial, which is of fundamental importance for developing real-time closed-loop neuromodulation systems. This work is a critical step toward developing a vital technique to study spinal cord function and effects of clinical neuromodulation.

Influence of Surface Treatments on Urea Detection Using Si Electrolyte-Gated Transistors with Different Gate Electrodes

We investigated the impact of surface treatments on Si-based electrolyte-gated transistors (EGTs) for detecting urea. Three types of EGTs were fabricated with distinct gate electrodes (Ag, Au, Pt) using a top-down method. These EGTs exhibited exceptional intrinsic electrical properties, including a low subthreshold swing of 80 mV/dec, a high on/off current ratio of 106, and negligible hysteresis. Three surface treatment methods ((3-amino-propyl) triethoxysilane (APTES) and glutaraldehyde (GA), 11-mercaptoundecanoic acid (11-MUA), 3-mercaptopropionic acid (3-MPA)) were individually applied to the EGTs with different gate electrodes (Ag, Au, Pt). Gold nanoparticle binding tests were performed to validate the surface functionalization. We compared their detection performance of urea and found that APTES and GA exhibited the most superior detection characteristics, followed by 11-MUA and 3-MPA, regardless of the gate metal. APTES and GA, with the highest pKa among the three surface treatment methods, did not compromise the activity of urease, making it the most suitable surface treatment method for urea sensing.

Sensing Characteristics of SARS-CoV-2 Spike Protein Using Aptamer-Functionalized Si-Based Electrolyte-Gated Field-Effect Transistor (EGT)

The sensing responses of SARS-CoV-2 spike protein using top-down-fabricated Si-based electrolyte-gated transistors (EGTs) have been investigated. An aptamer was employed as a receptor for the SARS-CoV-2 spike protein. The EGT demonstrated excellent intrinsic characteristics and higher sensitivity in the subthreshold regime compared to the linear regime. The limit of detection (LOD) was achieved as low as 0.94 pg/mL and 20 pg/mL for the current and voltage sensitivity, respectively. To analyze the sensing responses of EGT in detecting the aptamer-SARS-CoV-2 spike protein conjugate, a lumped-capacitive model with the presence of an effective dipole potential and an effective capacitance of the functionalized layer component was employed. The aptamer-functionalized EGT showed high sensitivity even in 10 mM phosphate-buffered saline (PBS) solution. These results suggest that Si-based EGTs are a highly promising method for detecting SARS-CoV-2 spike proteins.

Association of Molecular Subtypes with Pathologic Response, PFS, and OS in a Phase II Study of COXEN with Neoadjuvant Chemotherapy for Muscle-invasive Bladder Cancer

PURPOSE

The Coexpression Extrapolation (COXEN) gene expression model with chemotherapy-specific scores [for methotrexate, vinblastine, adriamycin, cisplatin (ddMVAC) and gemcitabine/cisplatin (GC)] was developed to identify responders to neoadjuvant chemotherapy (NAC). We investigated RNA-based molecular subtypes as additional predictive biomarkers for NAC response, progression-free survival (PFS), and overall survival (OS) in patients treated in S1314.

EXPERIMENTAL DESIGN

A total of 237 patients were randomized between four cycles of ddMVAC (51%) and GC (49%). On the basis of Affymetrix transcriptomic data, we determined subtypes using three classifiers: TCGA (k = 5), Consensus (k = 6), and MD Anderson (MDA; k = 3) and assessed subtype association with path response to NAC and determined associations with COXEN. We also tested whether each classifier contributed additional predictive power when added to a model based on predefined stratification (strat) factors (PS 0 vs. 1; T2 vs. T3, T4a).

RESULTS

A total of 155 patients had gene expression results, received at least three of four cycles of NAC, and had pT-N response based on radical cystectomy. TCGA three-group classifier basal-squamous (BS)/neuronal, luminal (Lum), Lum infiltrated, and GC COXEN score yielded the largest AUCs for pT0 (0.59, P = 0.28; 0.60, P = 0.18, respectively). For downstaging (

CONCLUSIONS

The Consensus classifier, based in part on the TCGA and MDA classifiers, modestly improved prediction for pathologic downstaging but subtypes were not associated with PFS or OS.

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Key Words Collapse

MESH Headings

• Humans
• Cisplatin/therapeutic use
• Cystectomy/methods
• Deoxycytidine/therapeutic use
• Muscles/pathology
• Neoadjuvant Therapy/methods
• Neoplasm Invasiveness
• Progression-Free Survival
• Retrospective Studies
• Urinary Bladder Neoplasms/drug therapy
• Urinary Bladder Neoplasms/genetics
• Urinary Bladder Neoplasms/pathology

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Grants

• UG1 CA233320 NCI NIH HHS
• UG1 CA233324 NCI NIH HHS
• UG1 CA180830 NCI NIH HHS
• UG1 CA233160 NCI NIH HHS
• U10 CA032102 NCI NIH HHS
• UG1 CA233196 NCI NIH HHS
• U10 CA180888 NCI NIH HHS
• U24 CA114748 NCI NIH HHS
• U10 CA180819 NCI NIH HHS
• UG1 CA233328 NCI NIH HHS

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Novel Deep Learning Segmentation Models for Accurate GTV and OAR Segmentation in MR-Guided Adaptive Radiotherapy for Pancreatic Cancer Patients

PURPOSE/OBJECTIVE(S)

MR-guided adaptive radiotherapy (MRgART) improves target coverage and organ-at-risk (OAR) sparing in pancreatic cancer radiation therapy (RT). Inter-fractional changes in patients undergoing RT require time intensive re-delineation of gross tumor volume (GTV) and OARs prior to adaptive optimization. Accurate automatic segmentation has the potential to significantly improve efficiency of the adaptive workflow. We hypothesized that state-of-the-art deep learning (DL) segmentation models could adequately segment GTV and OARs in both planning and daily fractional MR scans.

MATERIALS/METHODS

The study included 21 patients with pancreatic cancer treated with MRgART (10 Gy x 5 fractions). The planning MR as well as all daily MR images and registrations were collected (6 image sets per patient and a total of 126 image sets). The planning MR and fraction 1-4 image sets were used as the training set (N = 105), while the test set (N = 21) comprised images for fraction 5, to simulate the last step of incremental learning from planning to final fraction. Evaluated contours included the GTV, Small Bowel, Large Bowel, Duodenum, Left and Right Kidney, Liver, Spinal Cord, and Stomach. To mimic clinical conditions, contour accuracy was evaluated within the ring structure surrounding the PTV, inside of which daily adaptive re-contouring is applied (2 cm expansion in the cradio-caudal direction, 3 cm expansion otherwise). We evaluated three DL model architectures: SegResNet, SegResNet 2D, and SwinUNETR to autosegment GTV and OARs. The segmentation models were trained on the training set using 5-fold cross-validation (CV) and quantitatively analyzed by comparing against clinically used contours with DICE scores. Qualitative analysis was performed by a radiation oncologist using a scoring scale: 1 = perfect, 2 = minor discrepancy, 3 = moderate discrepancy, and 4 = rejected.

RESULTS

Overall, the DL segmentations were in acceptable agreement with clinical contours. The best performing model was the SwinUNETR model with overall training DICE = 0.88±0.06, test DICE = 0.78±0.11, and qualitative score of 1.6±0.8. The agreement between the DL model and clinical segmentation for the GTV was 0.79±0.08, with a qualitative score of 2.2±0.9. The highest and lowest OAR DICE scores were for the Left Kidney (DICE = 0.93) and Small Bowel (DICE = 0.68), respectively. The highest qualitative OAR scores were for the Kidney, Liver, and Spinal Cord (score = 1.0) and the lowest qualitative score was for the Duodenum (score = 2.3) CONCLUSION: We report here the most comprehensive work on DL segmentation for pancreatic cancer MRgART, including quantitative and clinically-pertinent qualitative evaluations of 126 image sets and 3 DL architectures. Our data show good quantitative agreement between DL and clinical contours, and acceptable clinician evaluations for the majority of GTVs and OARs. The current work has great potential to significantly reduce a major bottleneck in the MRgART workflow for pancreatic cancer patients.

Novel Functional Radiomics for Prediction of Cardiac PET Avidity in Lung Cancer Radiotherapy

PURPOSE/OBJECTIVE(S)

Traditional methods of evaluating cardiotoxicity focus solely on radiation doses to the heart and do not incorporate functional imaging information. Functional imaging has great potential to improve the ability to provide early prediction for cardiotoxicity for lung cancer patients undergoing radiotherapy. FDG-based PET/CT imaging is routinely obtained as part of standard staging work up for lung cancer patients. Although FDG PET/CT scans are typically used to evaluate the tumor, imaging guidelines note that FDG PET/CT scans are an FDA-approved method to image for cardiac inflammation, and studies have noted that the PET cardiac signal can be predictive of clinical outcomes. The purpose of this work was to develop a radiomics model to predict clinical cardiac assessment of standard of care FDG PET/CT scans.

MATERIALS/METHODS

The study included 100 consecutive lung cancer patients treated with radiotherapy who underwent standard pre-treatment FDG-PET/CT staging scans. A clinician reviewed the PET/CT scans per clinical cardiac assessment guidelines and classified the cardiac uptake as: 0 = uniform diffuse, 1 = absent, 2 = heterogeneous, with event rates of 20%, 44%, and 35%, respectively. The heart was delineated and 200 novel functional radiomics features were selected to classify cardiac FDG uptake patterns. We divided the data into an 80% training set and a 20% test set to train and evaluate the classification models. Feature reduction was carried out using the Wilcoxon test (with Bonferroni adjusted p<0.05), hierarchical clustering, and Recursive Feature Elimination. Two automatic machine learning (AutoML) frameworks were used to determine classification models: a Random Forest Classifier (Tree-based Pipeline Optimization Tool, TPOT) and Linear Discriminant Analysis (AutoSklearn). 10-fold cross validation was carried out for training and the accuracy of the ability of the models to predict for clinical cardiac assessment is reported.

RESULTS

Fifty-one independent radiomics features were reduced to 3 clinically pertinent features (PET 2D Skewness, PET Grey Level Co-occurrence Matrix Correlation, and PET Median) using feature reduction techniques. The model selected by TPOT showed 89.8% predictive accuracy in the cross validation of the training set and 85% predictive accuracy on the test set. The model selected by AutoSklearn showed 89.7% predictive accuracy in the cross validation of the training set and 80% predictive accuracy on the test set.

CONCLUSION

The novelty of this work is that it is the first study to develop and evaluate functional cardiac radiomic features from standard of care FDG PET/CT scans with the data showing good predictive accuracy with clinical imaging evaluation. If validated, the current work provides automated methods to provide functional cardiac information using standard of care imaging that can be used as an imaging biomarker for early clinical toxicity prediction for lung cancer patients.

Deep-Learning Based Auto-Segmentation for Liver Yttrium-90 Selective Internal Radiation Therapy

PURPOSE/OBJECTIVE(S)

In resin Yttrium-90 (Y-90) selective internal radiation therapy (SIRT), liver volume sizes are needed for Y-90 activity calculations using the body-surface-area method, which are obtained from contours that are manually delineated in 3D images. The aim was to apply a deep-learning based auto-segmentation method for liver delineation for Y-90 SIRT.

MATERIALS/METHODS

A deep-learning-based liver segmentation method was applied using the U-Net3D architecture, which is a 3D convolutional neural network (CNN) extended from the original 2D U-Net architecture for 3D objects in medical imaging. The segmentation model was trained on the Liver Tumor Segmentation (LiTS) dataset. The training data set contained 130 CT scans, and the test data set contained 70 CT scans. The model was deployed in the clinic using DICOM communication. Auto-segmentation of liver in the CT images of 18 SIRT patients was studied. The CT images were exported from clinical database to the segmentation model's DICOM location, where a monitoring software detected the incoming data and automatically ran the liver segmentation. The results were then returned to the original DICOM location where the CT images were stored. Auto-segmented liver contours were compared with physician manually-delineated contours. Dice similarity coefficient (DSC), mean distance to agreement (MDA), ratio of volume (RV), and ratio of activity (RA, ratio of activity calculated using an auto-segmented liver contour to the accurate activity calculated using a manually-delineated contour), were assessed.

RESULTS

DSC, MDA, and RV are 0.942±0.014 (range: 0.908-0.959), 1.902±0.503 mm (range: 1.043-2.956 mm), and 0.988±0.039 (range: 0.901-1.045), respectively. RA is 1.001±0.003 (range: 0.993-1.007), which indicates that the activities calculated using the auto-segmented liver contours are close to the accurate activities.

CONCLUSION

The segmentation model was able to successfully identify and segment livers in the CT images, and provide accurate and reliable results. The proposed method is beneficial for clinical use as it can process large amounts of data quickly and efficiently, and can be easily deployed in a clinical environment using DICOM communication.

Sybodies as Novel Bioreceptors toward Field-Effect Transistor-Based Detection of SARS-CoV-2 Antigens

The SARS-CoV-2 pandemic has increased the demand for low-cost, portable, and rapid biosensors, driving huge research efforts toward new nanomaterial-based approaches with high sensitivity. Many of them employ antibodies as bioreceptors, which have a costly development process that requires animal facilities. Recently, sybodies emerged as a new alternative class of synthetic binders and receptors with high antigen binding efficiency, improved chemical stability, and lower production costs via animal-free methods. Their smaller size is an important asset to consider in combination with ultrasensitive field-effect transistors (FETs) as transducers, which respond more intensely when biorecognition occurs near their surface. This work demonstrates the immobilization of sybodies against the spike protein of the virus on silicon surfaces, which are often integral parts of the semiconducting channel of FETs. Immobilized sybodies maintain the capability to capture antigens, even at low concentrations in the femtomolar range, as observed by fluorescence microscopy. Finally, the first proof of concept of sybody-modified FET sensing is provided using a nanoscopic silicon net as the sensitive area where the sybodies are immobilized. The future development of further sybodies against other biomarkers and their generalization in biosensors could be critical to decrease the cost of biodetection platforms in future pandemics.

Highly Sensitive Detection of Urea Using Si Electrolyte-Gated Transistor with Low Power Consumption

We experimentally demonstrate Si-based electrolyte-gated transistors (EGTs) for detecting urea. The top-down-fabricated device exhibited excellent intrinsic characteristics, including a low subthreshold swing (SS) (~80 mV/dec) and a high on/off current ratio (~10⁷). The sensitivity, which varied depending on the operation regime, was analyzed with the urea concentrations ranging from 0.1 to 316 mM. The current-related response could be enhanced by reducing the SS of the devices, whereas the voltage-related response remained relatively constant. The urea sensitivity in the subthreshold regime was as high as 1.9 dec/pUrea, four times higher than the reported value. The extracted power consumption of 0.3 nW was extremely low compared to other FET-type sensors.

New Constraint on the Local Relic Neutrino Background Overdensity with the First KATRIN Data Runs

We report on the direct search for cosmic relic neutrinos using data acquired during the first two science campaigns of the KATRIN experiment in 2019. Beta-decay electrons from a high-purity molecular tritium gas source are analyzed by a high-resolution MAC-E filter around the end point at 18.57 keV. The analysis is sensitive to a local relic neutrino overdensity ratio of η<9.7×10^{10}/α (1.1×10^{11}/α) at a 90% (95%) confidence level with α=1 (0.5) for Majorana (Dirac) neutrinos. A fit of the integrated electron spectrum over a narrow interval around the end point accounting for relic neutrino captures in the tritium source reveals no significant overdensity. This work improves the results obtained by the previous neutrino mass experiments at Los Alamos and Troitsk. We furthermore update the projected final sensitivity of the KATRIN experiment to η<1×10^{10}/α at 90% confidence level, by relying on updated operational conditions.

An Ultrasensitive Silicon-Based Electrolyte-Gated Transistor for the Detection of Peanut Allergens

The highly sensitive detection of peanut allergens (PAs) using silicon-based electrolyte-gated transistors (Si-EGTs) was demonstrated. The Si-EGT was made using a top-down technique. The fabricated Si-EGT showed excellent intrinsic electrical characteristics, including a low threshold voltage of 0.7 V, low subthreshold swing of <70 mV/dec, and low gate leakage of <10 pA. Surface functionalization and immobilization of antibodies were performed for the selective detection of PAs. The voltage-related sensitivity (S_V) showed a constant behavior from the subthreshold regime to the linear regime. The current-related sensitivity (S_I) was high in the subthreshold regime and then significantly decreased as the drain current increased. The limit of detection (LOD) was calculated to be as low as 25 pg/mL based on S_I characteristics, which is the lowest value reported to date in the literature for various sensor methodologies. The Si-EGT showed selective detection of PA through a non-specific control test. These results confirm that Si-EGT is a high-sensitivity and low-power biosensor for PA detection.

Bound on 3+1 Active-Sterile Neutrino Mixing from the First Four-Week Science Run of KATRIN

We report on the light sterile neutrino search from the first four-week science run of the KATRIN experiment in 2019. Beta-decay electrons from a high-purity gaseous molecular tritium source are analyzed by a high-resolution MAC-E filter down to 40 eV below the endpoint at 18.57 keV. We consider the framework with three active neutrinos and one sterile neutrino. The analysis is sensitive to the mass, m_{4}, of the fourth mass state for m_{4}^{2}≲1000  eV^{2} and to active-to-sterile neutrino mixing down to |U_{e4}|^{2}≳2×10^{-2}. No significant spectral distortion is observed and exclusion bounds on the sterile mass and mixing are reported. These new limits supersede the Mainz results for m_{4}^{2}≲1000  eV^{2} and improve the Troitsk bound for m_{4}^{2}<30  eV^{2}. The reactor and gallium anomalies are constrained for 100<Δm_{41}^{2}<1000  eV^{2}.

Three-dimensional myocardial strain for the prediction of clinical events in patients with successfully reperfused ST-segment elevation myocardial infarction

Funding Acknowledgements

Type of funding sources: None.

Background/Introduction

Two-dimensional (2D) myocardial strain analysis can be used to evaluate the prognosis of patients with acute myocardial infarction and has comparable predictive power as conventional echocardiographic parameters such as left ventricular ejection fraction (LV EF). Three-dimensional (3D) myocardial strain analysis is also expected to have similar clinical usefulness and overcome several inherent limitations of 2D strain analysis. However, no large-scale studies have been reported to date.

Purpose

We aimed to clarify the prognostic significance of 3D strain analysis in patients with ST-segment elevation myocardial infarction (STEMI) who are most likely to benefit from 3D strain analysis.

Methods

 Patients who underwent successful revascularization for STEMI from June 2011 to April 2017 were retrospectively recruited. In addition to conventional echocardiographic parameters, 3D global area strain (GAS), 3D global longitudinal strain (GLS), as well as 2D GLS were obtained.

 To evaluate the clinical outcomes, we constructed a composite outcome consisting of all-cause death or re-hospitalisation due to acute decompensation of heart failure.

Results

From June 2011 to April 2017, 632 patients were retrospectively recruited in our hospital. Of these patients, 545 patients (86.2%) had a reliable 3D strain analysis. The clinical course of each patient was followed up for a maximum of 96 months (median 49.5 months). During follow-up periods, 55 (10.1%) among 545 patients experienced the composite outcome of all-cause death or re-hospitalisation due to acute decompensation of heart failure. Patients with adverse events were older, had more underlying diseases such as obesity, dyslipidemia, previous history of stroke, or chronic kidney disease. (all, p &lt; 0.05) LV EF was significantly lower, while 2D GLS, 3D GLS, and 3D GAS were significantly higher in patients with poor outcomes. (all, p &lt; 0.001) The area under the receiver operating characteristic curve (AUC) values of LV EF, 2D GLS, 3D GLS, and 3D GAS were 0.70, 0.71, 0.67, and 0.65, respectively. (all, p &lt; 0.05) Kaplan-Meier analysis of composite outcomes based on the best cut-off values of each parameter demonstrated similar results. (Figure 1) In the Cox proportional hazard model, the hazard ratios of LV EF, 2D GLS, and 3D GLS were 3.0, 5.5, and 2.0, respectively. (all, p &lt; 0.05) The maximum likelihood-ratio test was performed to evaluate the additional prognostic value of 2D GLS or 3D GLS over the basic prognostic model consisting of baseline clinical characteristics and LV EF, and the likelihood ratio was 15.9 for 2D GLS (p &lt; 0.001) and 1.49 for 3D GLS (p = 0.22).

Conclusion(s)

 3D strain could be reliably measured in the majority of the patients and had a significant prognostic value. However, the predictive power of the 3D strain was lower than that of the 2D strain. The clinical implications of 3D strain indices should be investigated further.

Abstract Figure.

3D wide-field multispectral photoacoustic imaging of human melanomas in vivo: a pilot study

BACKGROUND

The Breslow depth is an important parameter to determine the excision margin and prognosis of melanoma. However, it is difficult to accurately determine the actual Breslow depth before surgery using the existing ocular micrometer and biopsy technique.

OBJECTIVES

To evaluate the use of 3D wide-field multispectral photoacoustic imaging to non-invasively measure depth and outline the boundary of melanomas for optimal surgical margin selection.

METHODS

Six melanoma patients were examined in vivo using the 3D multispectral photoacoustic imaging system. For five cases of melanomas (one in situ, three nodular, and one acral lentiginous type melanoma), the spectrally unmixed photoacoustic depths were calculated and compared against histopathological depths.

RESULTS

Spectrally unmixed photoacoustic depths and histopathological depths match well within a mean absolute error of 0.36 mm. In particular, the measured minimum and maximum depths in the in situ and nodular type of melanoma were 0.6 and 9.1 mm, respectively. In the 3D photoacoustic image of one metastatic melanoma, feeding vessels were visualized in the melanoma, suggesting the neovascularization around the tumour.

CONCLUSIONS

The 3D multispectral photoacoustic imaging not only provides well-measured depth and sizes of various types of melanomas, it also visualizes the metastatic type of melanoma. Obtaining accurate depth and boundary information of melanoma before surgery would play a useful role in the complete excision of melanoma during surgery.

Reproducibility of Histologic Assessment in Porto-sinusoidal Vascular Disease Liver Biopsies

Introduction/Objective

Variable histologic findings that may be seen in porto-sinusoidal vascular disease (PSVD) liver biopsies are subject to high interobserver variability, requiring correlation with clinical history of portal hypertension (traditionally interpreted as non-cirrhotic portal hypertension NCPH). We investigated which histologic features are reproducible in PSVD biopsies.

Methods

Archived liver biopsies (n=38) from patients with NCPH (n=14) and without NCPH (n=21) were reviewed. Static H&E images of lobules (L, x100, NCPH=27, non-NCPH=23) and portal tracts (P, x200, NCPH=23, non- NCPH=27) were distributed among 9 gastrointestinal pathologists blinded to clinical history. Each pathologist answered multiple choice questions based on the presence (Q2) or absence (Q1) of portal hypertension clinically. The choice selected by 6 pathologists or more was considered consensus answer for the image. The interpretation of the image was considered reproducible when consensus was reached on both Q1 and Q2.

Results

The interpretations of 27 (54%; 17L, 10P) images from NCPH and 21 (42%; 10L, 11P) from non-NCPH were reproducible. In NCPH, the interpretations of normal (n=10, 4L, 6P), sinusoidal dilatation (n=7), and increased parenchymal draining vessels (n=3) were reproducible, while there was no consensus on the diagnoses of nodular regeneration and increased number of portal vessels. In non-NCPH, the interpretations of normal (n=8, 2L, 6P), sinusoidal dilatation (n=6), and paraportal shunting vessel(s) (n=4) were reproducible, whereas no consensus was reached on the diagnoses of nodular regeneration, incomplete fibrous septa, and increased number of portal vessels.

Conclusion

Histologic assessment of normal L and P as well as sinusoidal dilatation appears to be reproducible independent of clinical history. The findings of increased parenchymal draining vessels in NCPH group and paraportal shunting vessels in non-NCPH group may be consistently diagnosed to a certain extent. The assessment for nodular regeneration without reticulin stain, incomplete fibrous septa, or increased number of portal vessels appears to be unreliable.

Epigenetic profiling demarcates molecular subtypes of muscle-invasive bladder cancer

Muscle-invasive bladder cancer (MIBC) is a heterogeneous disease that often recurs despite aggressive treatment with neoadjuvant chemotherapy and (radical) cystectomy. Basal and luminal molecular subtypes have been identified that are linked to clinical characteristics and have differential sensitivities to chemotherapy. While it has been suggested that epigenetic mechanisms play a role in defining these subtypes, a thorough understanding of the biological mechanisms is lacking. This report details the first genome-wide analysis of histone methylation patterns of human primary bladder tumours by chromatin immunoprecipitations and next-generation sequencing (ChIP-seq). We profiled multiple histone marks: H3K27me3, a marker for repressed genes, and H3K4me1 and H3K4me3, which are indicators of active enhancers and active promoters. Integrated analysis of ChIP-seq data and RNA sequencing revealed that H3K4 mono-methylation demarcates MIBC subtypes, while no association was found for the other two histone modifications in relation to basal and luminal subtypes. Additionally, we identified differentially methylated H3K4me1 peaks in basal and luminal tumour samples, suggesting that active enhancers play a role in defining subtypes. Our study is the first analysis of histone modifications in primary bladder cancer tissue and provides an important resource for the bladder cancer community.

Improved Upper Limit on the Neutrino Mass from a Direct Kinematic Method by KATRIN

We report on the neutrino mass measurement result from the first four-week science run of the Karlsruhe Tritium Neutrino experiment KATRIN in spring 2019. Beta-decay electrons from a high-purity gaseous molecular tritium source are energy analyzed by a high-resolution MAC-E filter. A fit of the integrated electron spectrum over a narrow interval around the kinematic end point at 18.57 keV gives an effective neutrino mass square value of (-1.0_{-1.1}^{+0.9})  eV^{2}. From this, we derive an upper limit of 1.1 eV (90% confidence level) on the absolute mass scale of neutrinos. This value coincides with the KATRIN sensitivity. It improves upon previous mass limits from kinematic measurements by almost a factor of 2 and provides model-independent input to cosmological studies of structure formation.

P1740Clinical impact of symptom onset-to-balloon time and door-to-balloon time on 1-year adverse event in patients with ST-segment elevation myocardial infarction

Background and objectives

The impact of treatment delays to reperfusion on patient mortality after primary percutaneous coronary intervention (PCI) for ST elevation myocardial infarction (STEMI) is controversial. we evaluated the relation between the delay in the time to reperfusion during primary PCI and the 1-year clinical outcome of patients with STEMI treated by primary angioplasty.

Methods

The study enrolled 6,676 patients (age, 62.5±12.6 years; 26.5% female) with STEMI who underwent primary angioplasty onset between November 2005 and March 2012 from the KAMIR and KorMI Registry. The patients were divided into three groups according to the symptom onset-to-balloon (STB) time: group I, II, III (≤180 minutes, >180 ∼ ≤360 minutes, >360 minutes), and divided into three groups according to the door-to-balloon (DTB) time: group A, B, C (≤90 minutes, >90 ∼ ≤120 minutes, >120 minutes). The 1-year cardiac death and major adverse cardiac event (MACE) rates were compared among the three groups of time variables

Results

The cardiac death rate was 7.9% and MACE rate was 16.9% at one year follow-up. The 1-year cardiac death rate among STB time groups were significantly higher in group II (95% CI=1.05–2.60:p=0.030) and group III (95% CI=1.14–2.74:p=0.011), while that among DTB time groups were not significantly different based on a multivariate Cox proportional analysis, which was adjusted by age, sex, diabetes mellitus, hypertension, systolic blood pressure, left ventricular ejection fraction, peak level of CK-MB, anterior myocardial infarction. The 1-year MACE rate were not significantly different among STB time groups and DTB time group A, B, but was significantly higher in group C (95% CI=1.08–1.58:p=0.006).

Conclusions

These results suggest that, in patient with STEMI treated by primary angioplasty, STB time rather than DTB time was related 1-year clinical outcome especially cardiac death after adjustment for baseline characteristics. Therefore, all efforts should be made to shorten the total ischemic time in patients with acute myocardial infarction

Nosocomial person-to-person transmission of severe fever with thrombocytopenia syndrome

OBJECTIVES

This study is an epidemiologic investigation of nosocomial severe fever with thrombocytopenia syndrome virus (SFTSV) transmission among healthcare workers (HCWs) after contact with an index patient. The aim of this study was to determine whether exposure to blood or bloody respiratory secretion is associated with human-to-human transmission of SFTSV.

METHODS

Eleven days after the index patient died, two HCWs who had close exposure to the patient presented with typical symptoms of SFTS. An epidemiological investigation was conducted on all 25 HCWs who had been in close contact with the index patient. Clinical and laboratory data were collected, and transmission rate before and after the index patient had haemorrhagic manifestations was analysed.

RESULTS

Among 25 HCWs who had direct contact with the index patient, five HCWs were confirmed to have SFTS. All five HCWs had contact to blood or bloody respiratory secretions of the index patient without adequate use of personal protective equipment (PPE). No HCW with contact before haemorrhagic manifestations of the index patient contracted SFTS. Overall, the transmission rate was higher for HCWs who had contact after the index patient had haemorrhagic manifestations (33.3%, five of 15 HCWs, vs. 0%, zero of ten HCWs, p 0.041).

CONCLUSIONS

In HCWs who are inadequately protected, person-to-person transmission of SFTSV may be associated with contact with blood or bloody respiratory secretions. Therefore, universal precaution and full PPE is highly recommended for protection against SFTSV when there are signs of bleeding.

Clinical outcomes of 23 patients who had repeat pelvic arterial embolisation for uncontrolled post-partum haemorrhage at a single centre

AIM

To evaluate the safety and efficacy of repeated pelvic arterial embolisation (PAE) for uncontrolled postpartum haemorrhage (PPH) after a single session of PAE and to compare angiographic findings between the two sessions of PAE.

MATERIALS AND METHODS

A total of 23 consecutive patients (age range, 23-44 years) who underwent repeated PAE for uncontrolled PPH between March 2001 and January 2016 in Severance Hospital were reviewed. The interval times between the two sessions of PAE, the angiographic findings, embolic materials, arteries embolised during PAE, and the clinical outcomes were reviewed retrospectively.

RESULTS

Overall clinical success was achieved after repeated PAE in 21 of 23 patients (91.3%). There were no procedure-related, major complications. On angiography, active bleeding from the uterine collateral arteries was more frequently observed in the second session of PAE (p>0.05), and embolisation of the anterior division of the internal iliac artery was significantly higher during the second session of PAE. Use of permanent embolic materials was significantly higher during the second session of PAE. Recanalisation of a previously embolised artery was identified in 14 patients (60.9%) during the second session.

CONCLUSION

Repeated PAE is safe and effective for managing recurrent bleeding after a single session of PAE. Repeated PAE is related to a higher chance of embolisation of the anterior division of the internal iliac artery, with the use of permanent embolic materials. Recanalisation of a previously embolised artery seems to be a principal source of rebleeding during a repeated session of PAE.

Evolving affinity between Coulombic reversibility and hysteretic phase transformations in nano-structured silicon-based lithium-ion batteries

Nano-structured silicon is an attractive alternative anode material to conventional graphite in lithium-ion batteries. However, the anode designs with higher silicon concentrations remain to be commercialized despite recent remarkable progress. One of the most critical issues is the fundamental understanding of the lithium-silicon Coulombic efficiency. Particularly, this is the key to resolve subtle yet accumulatively significant alterations of Coulombic efficiency by various paths of lithium-silicon processes over cycles. Here, we provide quantitative and qualitative insight into how the irreversible behaviors are altered by the processes under amorphous volume changes and hysteretic amorphous-crystalline phase transformations. Repeated latter transformations over cycles, typically featured as a degradation factor, can govern the reversibility behaviors, improving the irreversibility and eventually minimizing cumulative irreversible lithium consumption. This is clearly different from repeated amorphous volume changes with different lithiation depths. The mechanism behind the correlations is elucidated by electrochemical and structural probing.

81 Effects of Day 5 or 6 HEPES-Buffered Transportation Culture Medium on Developmental Competence of Bovine In Vitro-Produced Embryos

Most in vitro-produced (IVP) bovine embryos are transferred fresh. Use of a HEPES/bicarbonate embryo culture medium for transportation would offer flexibility for embryo shipment and transfer. We hypothesized that embryos cultured for 36 (Day 6 embryos) or 60 h (Day 5 embryos) in a novel SCF1T medium (SOF for Conventional Freezing 1 supplemented with HEPES) would maintain developmental competence compared with bicarbonate-buffered medium SCF1 (control). In 5 replicates, IVP embryos were produced by aspirating cumulus–oocyte complexes (COC) from 2-to 8-mm follicles of abattoir ovaries. The COC (n = 1036) were matured for 23 h, fertilized with semen from 1 of 3 bulls, and cultured in SCF1 at 38.5°C, 5% CO2, 5% O2, and 90% N2 (Owen et al. 2017 Reprod. Fertil. Dev. 29, 129-130). Randomly, on Day 5 and 6 after fertilization, a subset of presumptive embryos were moved into 500-µL polystyrene vials containing 100 µL of SCF1T medium, covered with 300 µL of sterile mineral oil and cultured in a portable incubator (MicroQ iQ2, Scottsdale, AZ, USA) at 38.5°C for 60 and 36 h, respectively. On Day 7.5 post-fertilization, blastocyst rates were evaluated and embryos (n = 8) from each group were stained with 1 µg mL−1 Nile Red for lipid quantification, and 300 nM Mitotracker Red CMX-Rosamine (Thermo Fisher Scientific, Waltham, MA, USA) for mitochondrial polarity. Images were obtained with confocal microscopy and fluorescent intensity (AFU) was measured by Image J software (National Institutes of Health, Bethesda, MD, USA). Data were analysed by one-way ANOVA and means separated by Tukey’s HSD. Results (Table 1) indicate similar blastocyst rates and lipid content between embryos cultured for 36 to 60 h in SCF1T and control media (P > 0.05). However, mitochondrial polarity was lower in the Day 5 group (P < 0.05) compared with Day 6 and control groups. Results suggest that culturing embryos in SCF1T medium for 36 h maintains developmental competence compared with bicarbonate-buffered media and offers an alternative for shipment and transfer of IVP embryos. Studies involving evaluation of pregnancy rates of the present study are ongoing. Table 1.Effects of Day 5 or 6 SCF1T embryo culture medium on development, lipid content, and mitochondrial polarity