Association between waist circumference change after smoking cessation and incidence of hypertension in Korean adults

OBJECTIVES

This study investigates the association between smoking cessation and hypertension incidence, as well as the association between waist circumference change after smoking cessation and hypertension incidence.

STUDY DESIGN

This was a nationwide population-based cohort study.

METHODS

We used the Korean Health Screening Cohort data and included 158,505 participants who had undergone two or more health examinations between 2008 and 2011, with follow-ups throughout 2019. Smoking cessation and waist changes were captured based on difference between first and follow-up screening dates. Hazard ratio (HR) and 95% confidence interval (CI) for hypertension risk were estimated using multivariable Cox proportional hazard regression models.

RESULTS

There were 31,270 cases of hypertension during a median follow-up of 8.50 years. After adjusting for potential confounding factors, HR for hypertension were 1.01 (95% CI: 0.97-1.05), 0.91 (95% CI: 0.87-0.95), and 0.88 (95% CI: 0.85-0.91) for recent quitters, long-term quitters, and non-smokers, respectively, compared with current smokers. HR for hypertension, compared with current smokers, were 0.89 (95% CI: 0.84-0.94), 0.91 (95% CI: 0.85-0.97), and 0.99 (95% CI: 0.91-1.08) for long-term quitters with no waist gain, long-term quitters with waist gain of 0.1-5.0 cm, and long-term quitters with waist gain of ≥5.0 cm, respectively.

CONCLUSIONS

Long-term smoking cessation was significantly associated with decreased risk of hypertension, and long-term smoking cessation with no waist gain or less than 5.0 cm of waist gain was significantly associated with decreased risk of hypertension. However, more than 5.0 cm of waist gain can attenuate the effect of long-term smoking cessation on lowering the risk of hypertension.

A Mutation of a Putative NDP-Sugar Epimerase Gene in Ralstonia pseudosolanacearum Attenuates Exopolysaccharide Production and Bacterial Virulence in Tomato Plant

Ralstonia solanacearum species complex (RSSC) is a soil borne plant pathogen causing bacterial wilt on various important crops, including Solanaceae plants. The bacterial pathogens within the RSSC produce exopolysaccharide (EPS), a highly complicated nitrogen-containing heteropolymeric polysaccharide, as a major virulence factor. However, the biosynthetic pathway of the EPS in the RSSC has not been fully characterized. To identify genes in EPS production beyond the EPS biosynthetic gene operon, we selected the EPS-defective mutants of R. pseudosolanacearum strain SL341 from Tn5-inserted mutant pool. Among several EPS-defective mutants, we identified a mutant, SL341P4, with a Tn5-insertion in a gene encoding a putative NDP-sugar epimerase, a putative membrane protein with sugar-modifying moiety, in a reverse orientation to EPS biosynthesis gene cluster. This protein showed similar to other NDP-sugar epimerases involved in EPS biosynthesis in many phytopathogens. Mutation of the NDP-sugar epimerase gene reduced EPS production and biofilm formation in R. pseudosolanacearum. Additionally, the SL341P4 mutant exhibited reduced disease severity and incidence of bacterial wilt in tomato plants compared to the wild-type SL341 without alteration of bacterial multiplication. These results indicate that the NDP-sugar epimerase gene is required for EPS production and bacterial virulence in R. pseudosolanacearum.

Trans-anal small bowel evisceration in a patient with a perforated rectal prolapse

SUMMARY

An 85-year-old lady with a history of chronic constipation presented with gangrenous small bowel protruding from the anus through a hole in a prolapsed rectum. At surgery, a resection of 125 cm of gangrenous small bowel was performed in the perineum prior to laparotomy, where rectal repair was followed by the creation of a sigmoid loop colostomy and double-barrel ileostomy. This avoided an intrabdominal anastomosis which was felt likely to complicate due to the lady's intraoperative haemodynamic instability requiring inotropic support. This tailored management of a trans-anal small bowel evisceration through a rectal prolapse resulted in recovery and a patient who was content with her stomas and preferred to live with them rather than have continuity restored.

Phase II study of a trastuzumab biosimilar in combination with paclitaxel for HER2-positive recurrent or metastatic urothelial carcinoma: KCSG GU18-18

BACKGROUND

Human epidermal growth factor receptor 2 (HER2) is a widely explored therapeutic target in solid tumors. We evaluated the efficacy and safety of trastuzumab-pkrb, a biosimilar of trastuzumab, in combination with paclitaxel, in HER2-positive recurrent or metastatic urothelial carcinoma (UC).

PATIENTS AND METHODS

We enrolled 27 patients; they were administered a loading dose of 8 mg/kg trastuzumab-pkrb on day 1, followed by 6 mg/kg and 175 mg/m2 paclitaxel on day 1 every 3 weeks, intravenously. All patients received six cycles of the combination treatment and continued to receive trastuzumab-pkrb maintenance until disease progression, unacceptable toxicity, or for up to 2 years. HER2 positivity (based on immunohistochemistry analysis) was determined according to the 2013 American Society of Clinical Oncology /College of American Pathologists HER2 testing guidelines. The primary endpoint was objective response rate (ORR); the secondary endpoints were overall survival (OS), progression-free survival (PFS), and safety.

RESULTS

Twenty-six patients were evaluated via primary endpoint analysis. The ORR was 48.1% (1 complete and 12 partial responses) and the duration of response was 6.9 months [95% confidence interval (CI) 4.4-9.3 months]. With a median follow-up of 10.5 months, the median PFS and OS were 8.4 months (95% CI 6.2-8.8 months) and 13.5 months (95% CI 9.8 months-not reached), respectively. The most common treatment-related adverse event (TRAE) of any grade was peripheral neuropathy (88.9%). The most common grade 3/4 TRAEs were neutropenia (25.9%), thrombocytopenia (7.4%), and anemia (7.4%).

CONCLUSIONS

Trastuzumab-pkrb plus paclitaxel demonstrates promising efficacy with manageable toxicity profiles in patients with HER2-positive recurrent or metastatic UC.

Delayed immune-mediated hepatitis after three cycles of pembrolizumab for the treatment of sinonasal melanoma

Immune checkpoint inhibitors (ICIs) are monoclonal antibodies that induce the anti-tumor effects of T cells by targeting co-inhibitory immune checkpoints. The development of ICIs has revolutionized the clinical practice of oncology, leading to significant improvements in outcomes; therefore, ICIs are now standard care for various types of solid cancers. Immune-related adverse events, the unique toxicity profiles of ICIs, usually develop 4-12 weeks after initiation of ICI treatment; however, some cases can occur >3 months after cessation of ICI treatment. To date, there have been limited reports about delayed immune-mediated hepatitis (IMH) and histopathologic findings. Herein, we present a case of delayed IMH that occurred 3 months after the last dose of pembrolizumab, including histopathologic findings of the liver. This case suggests that ongoing surveillance for immune-related adverse events is required, even after cessation of ICI treatment.

Stachydrine alleviates lipid-induced skeletal muscle insulin resistance via AMPK/HO-1-mediated suppression of inflammation and endoplasmic reticulum stress

OBJECTIVE

Insulin resistance develops due to skeletal muscle inflammation and endoplasmic reticulum (ER) stress. Stachydrine (STA), extracted from Leonurus heterophyllus, has been shown to suppress proliferation and induce apoptosis in breast cancer cells and exert anti-inflammatory properties in the brain, heart, and liver. However, the roles of STA in insulin signaling in skeletal muscle remain unclear. Herein, we examined the impacts of STA on insulin signaling in skeletal muscle under hyperlipidemic conditions and its related molecular mechanisms.

METHODS

Various protein expression levels were determined by Western blotting. Levels of mouse serum cytokines were measured by ELISA.

RESULTS

We found that STA-ameliorated inflammation and ER stress, leading to attenuation of insulin resistance in palmitate-treated C2C12 myocytes. STA dose-dependently enhanced AMPK phosphorylation and HO-1 expression. Administration of STA attenuated not only insulin resistance but also inflammation and ER stress in the skeletal muscle of high-fat diet (HFD)-fed mice. Additionally, STA-ameliorated glucose tolerance and insulin sensitivity, as well as serum TNFα and MCP-1, in mice fed a HFD. Small interfering (si) RNA-associated suppression of AMPK or HO-1 expression abolished the effects of STA in C2C12 myocytes.

CONCLUSIONS

These results suggest that STA activates AMPK/HO-1 signaling, resulting in reduced inflammation and ER stress, thereby improving skeletal muscle insulin resistance. Using STA as a natural ingredient, this research successfully treated insulin resistance and type 2 diabetes.

Systemic proinflammatory-profibrotic response in aortic stenosis patients with diabetes and its relationship with myocardial remodeling and clinical outcome

Background

It is unclear whether and how diabetes mellitus may aggravate myocardial fibrosis and remodeling in the pressure-overloaded heart. We investigated the impact of diabetes on the prognosis of aortic stenosis (AS) patients and its underlying mechanisms using comprehensive noninvasive imaging studies and plasma proteomics.

Methods

Severe AS patients undergoing both echocardiography and cardiovascular magnetic resonance (CMR) (n=253 of which 66 had diabetes) comprised the imaging cohort. The degree of replacement and diffuse interstitial fibrosis by late gadolinium enhancement (LGE) and extracellular volume fraction (ECV) was quantified using CMR. Plasma samples were analyzed with the multiplex proximity extension assay for 92 proteomic biomarkers in a separate biomarker cohort of severe AS patients (n=100 of which 27 had diabetes).

Results

In the imaging cohort, diabetic patients were older (70.4±6.8 vs. 66.7±10.1 years) and had a higher prevalence of ischemic heart disease (28.8% vs. 9.1%), with more advanced ventricular diastolic dysfunction. On CMR, diabetic patients had increased replacement and diffuse interstitial fibrosis (LGE% 0.3 [0.0–1.6] versus 0.0 [0.0–0.5], p=0.009; ECV% 27.9 [25.7–30.1] versus 26.7 [24.9–28.5], p=0.025) (Figure 1).

Plasma proteomics analysis of the biomarker cohort revealed that 9 proteins (E-selectin, interleukin-1 receptor type 1, interleukin-1 receptor type 2, galectin-4, intercellular adhesion molecule 2, integrin beta-2, galectin-3, growth differentiation factor 15, and cathepsin D) are significantly elevated in diabetic AS patients (Figure 2). Pathway over-representation analyses of the plasma proteomics with Gene Ontology terms indicated that pathways related to inflammatory response and extracellular matrix components were enriched, suggesting that diabetes is associated with systemic effects that evoke proinflammatory and profibrotic response to the pressure-overloaded myocardium.

During follow-up (median 6.3 years [IQR 5.2–7.2]) of the imaging cohort, 232 patients received aortic valve replacement (AVR) with 53 unexpected heart failure admissions or death. Diabetes was a significant predictor of heart failure and death, independent of clinical covariates and AVR (hazard ratio 1.88, 95% confidence interval 1.06–3.31, p=0.030).

Conclusion

Plasma proteomic analyses indicate that diabetes potentiates the systemic proinflammatory and profibrotic milieu in AS patients. These systemic biological changes underlie the increase of myocardial fibrosis, diastolic dysfunction, and worse clinical outcomes in severe AS patients with concomitant diabetes.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): National Research Foundation of Korea

Augmented risk of ischemic stroke in hypertrophic cardiomyopathy patients without documented atrial fibrillation

Background

Ischemic stroke is a common complication in patients with hypertrophic cardiomyopathy (HCM) (1). Although atrial fibrillation (AF) is a well-established risk factor for ischemic stroke in HCM, the risk of ischemic stroke in patients with HCM without documented AF is less recognized (1, 2). This study aimed to determine the risk of ischemic stroke and identify its risk factors in patients with HCM without documented AF.

Methods

This nationwide population-based cohort study used the Korean National Health Insurance database. After excluding patients with a prior history of AF, thromboembolic events, cancer, or the use of anticoagulants, we identified 8,328 HCM patients without documented AF and 1:2 propensity score-matched 16,656 non-HCM controls. The clinical outcome was an incident ischemic stroke.

Results

During a mean follow-up of approximately 6 years, ischemic stroke occurred in 328/8,328 (3.9%) patients with HCM and 443/16,656 (2.7%) controls. Among individuals who developed ischemic stroke, the proportion of AF concomitantly detected accounted for 26.5% (87/328) and 5.8% (26/443) in the HCM and control groups, respectively. The overall incidence of ischemic stroke was 0.716/100 person-years in the HCM group, which was significantly higher than that in the control group (0.44/100 person-years) (HR 1.643; 95% CI, 1.424–1.895; P<0.001, Figure 1). The subgroup analysis according to age, sex, and comorbidities (chronic heart failure, hypertension, dyslipidemia, and vascular disease) consistently demonstrated a higher risk of ischemic stroke in the HCM group (P for interaction >0.05). In the HCM group, age ≥65 years (adjusted hazard ratio [HR] 2.741; 95% confidence interval [CI], 2.156–3.486; P<0.001) and chronic heart failure (adjusted HR 1.748; 95% CI, 1.101–2.745; P=0.018) were independent risk factors for ischemic stroke. Overall incidence was 1.360/100 in patients with HCM aged ≥65 and 2.315/100 person-years years in those with chronic heart failure, respectively. Also, compared to controls aged <65 years and without CHF, adjusted HR for ischemic stroke was 4.756 (95% CI 3.807–5.867) in patients with HCM aged ≥65 years and 2.539 (95% CI 1.638–3.936) in those with CHF, respectively (Figure 2).

Conclusions

Patients with HCM without documented AF are at a higher risk of ischemic stroke than the propensity score-matched general population. Age ≥65 years and chronic heart failure are two strong independent risk factors for ischemic stroke in this population.

Funding Acknowledgement

Type of funding sources: None.

Atomistic deformation mechanism of silicon under laser-driven shock compression

Silicon (Si) is one of the most abundant elements on Earth, and it is the most widely used semiconductor. Despite extensive study, some properties of Si, such as its behaviour under dynamic compression, remain elusive. A detailed understanding of Si deformation is crucial for various fields, ranging from planetary science to materials design. Simulations suggest that in Si the shear stress generated during shock compression is released via a high-pressure phase transition, challenging the classical picture of relaxation via defect-mediated plasticity. However, direct evidence supporting either deformation mechanism remains elusive. Here, we use sub-picosecond, highly-monochromatic x-ray diffraction to study (100)-oriented single-crystal Si under laser-driven shock compression. We provide the first unambiguous, time-resolved picture of Si deformation at ultra-high strain rates, demonstrating the predicted shear release via phase transition. Our results resolve the longstanding controversy on silicon deformation and provide direct proof of strain rate-dependent deformation mechanisms in a non-metallic system.

Understanding the how silicon deforms under pressure is important for several fields, including planetary science and materials design. Laser-driven shock compression experiments now confirm that shear stress generated during compression is released via a high-pressure phase transition.

Pan-Asian adapted ESMO Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with prostate cancer

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of prostate cancer was published in 2020. It was therefore decided, by both the ESMO and the Singapore Society of Oncology (SSO), to convene a special, virtual guidelines meeting in November 2021 to adapt the ESMO 2020 guidelines to take into account the differences associated with the treatment of prostate cancer in Asia. These guidelines represent the consensus opinions reached by experts in the treatment of patients with prostate cancer representing the oncological societies of China (CSCO), India (ISMPO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence and was independent of the current treatment practices and drug access restrictions in the different Asian countries. The latter were discussed when appropriate. The aim is to provide guidance for the optimisation and harmonisation of the management of patients with prostate cancer across the different regions of Asia.

Dynamic compression of water to conditions in ice giant interiors

Recent discoveries of water-rich Neptune-like exoplanets require a more detailed understanding of the phase diagram of H₂O at pressure–temperature conditions relevant to their planetary interiors. The unusual non-dipolar magnetic fields of ice giant planets, produced by convecting liquid ionic water, are influenced by exotic high-pressure states of H₂O—yet the structure of ice in this state is challenging to determine experimentally. Here we present X-ray diffraction evidence of a body-centered cubic (BCC) structured H₂O ice at 200 GPa and ~ 5000 K, deemed ice XIX, using the X-ray Free Electron Laser of the Linac Coherent Light Source to probe the structure of the oxygen sub-lattice during dynamic compression. Although several cubic or orthorhombic structures have been predicted to be the stable structure at these conditions, we show this BCC ice phase is stable to multi-Mbar pressures and temperatures near the melt boundary. This suggests variable and increased electrical conductivity to greater depths in ice giant planets that may promote the generation of multipolar magnetic fields.

Efflux pump gene expression study using RNA-seq in multidrug-resistant TB

BACKGROUND: The mechanism underlying kanamycin (KM) resistance in Mycobacterium tuberculosis is not well understood, although efflux pump proteins are thought to play a role. This study used RNA-seq data to investigate changes in the expression levels of efflux pump genes following exposure to KM.METHODS: RNA expression of efflux pump and regulatory genes following exposure to different concentrations of KM (minimum inhibitory concentration MIC 25 and MIC50) in rrs wild-type strain and rrs A1401G mutated strain were compared with the control group.RESULTS: The selected strains had differential RNA expression patterns. Among the 71 putative efflux pump and regulatory genes, 46 had significant fold changes, and 12 genes (Rv0842, Rv1146, Rv1258c, Rv1473, Rv1686c, Rv1687c, Rv1877, Rv2038c, Rv3065, Rv3197a, Rv3728 and Rv3789) that were overexpressed following exposure to KM were thought to contribute to drug resistance. Rv3197A (whiB7) showed a distinct fold change based on the concentration of KM.CONCLUSION: The significant changes in the expression of the efflux pump and regulatory genes following exposure to KM may provide insights into the identification of a new resistance mechanism.

Pan-Asian adapted ESMO Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with renal cell carcinoma

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of renal cell carcinoma was published in 2019 with an update planned for 2021. It was therefore decided by both the ESMO and the Singapore Society of Oncology (SSO) to convene a special, virtual guidelines meeting in May 2021 to adapt the ESMO 2019 guidelines to take into account the ethnic differences associated with the treatment of renal cell carcinomas in Asian patients. These guidelines represent the consensus opinions reached by experts in the treatment of patients with renal cell carcinoma representing the oncological societies of China (CSCO), India (ISMPO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence and was independent of the current treatment practices and drug access restrictions in the different Asian countries. The latter were discussed when appropriate.

Efficacy and safety of epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) monotherapy for advanced EGFR-mutated non-small cell lung cancer: systematic review and meta-analysis

OBJECTIVE

It is controversial whether there is efficacy or safety benefit of epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) in advanced EGFR-mutated non-small cell lung cancer (NSCLC) compared to standard chemotherapy. We aim to assess the efficacy and safety of EGFR-TKIs compared to other chemotherapeutics in EGFR-mutated NSCLC.

MATERIALS AND METHODS

Up to April 27th, 2020, PubMed, Embase, Medline, Scopus, Cochrane library, and ClinicalTrials.gov were searched for articles or trials meeting the inclusion criteria. After filtering, 230 eligible studies were initially identified. Data extraction followed PRISMA and included outcomes were progression-free survival (PFS), overall survival (OS), and severe adverse events (SAEs). Direct and indirect meta-analyses were generated in the context of log-linear mixed-effects models, with fixed effects for each relative comparison and random effects for each study.

RESULTS

The results showed that EGFR-TKI therapy had improved PFS with a hazard ratio (HR) of 0.40 (95% CI: 0.36-0.44, p<0.001) compared to standard chemotherapy. Nevertheless, the EGFR-TKIs showed no benefit on OS (HR: 0.96, 95% CI: 0.83-1.10, p=0.556). In the analysis of adverse events, EGFR-TKIs had fewer SAEs than standard chemotherapy (HR: 0.29, 95% CI: 0.26-0.33, p<0.001).

CONCLUSIONS

Our systemic review indicates that EGFR-TKI therapy has improved PFS, and reduced SAEs compared to standard chemotherapy in advanced EGFR-mutated NSCLC.

Risk of dementia according to smoking cessation after newly diagnosed atrial fibrillation: a nationwide cohort study

Background

Incident atrial fibrillation (AF) is associated with an increased risk of dementia. There are limited data about the impact of smoking cessation after AF diagnosis on the risk of incident dementia.

Purpose

To evaluate the association between changes in smoking status after newly diagnosed AF and the risk of dementia.

Methods

Among patients with new-onset AF between 2010 and 2016, those who received a national health checkup exam within 2 years before and after the AF diagnosis were included. Patients who had prevalent dementia were excluded. Subjects were categorized into 4 groups according to the status of smoking before and after AF diagnosis: (1) never smoker; (2) ex-smoker; (3) quit-smoker after AF diagnosis; and (4) current smoker. The primary outcome was incident dementia during follow-up.

Results

A total of 126,252 patients were included (mean age 63, SD 12.0; men 62%; mean CHA2DS2-VASc 2.7). During a median 3 years of follow-up, dementia occurred in 5,925 patients (1.11 per 1000 person-years [1000PY]) (Alzheimer's dementia 1.5 per 1000 PY and vascular dementia 0.24 per 1000 PY, respectively). Never smokers, ex-smokers, quit-smokers, and current smokers were 52%, 27%, 7%, and 14% of the total study population, respectively. After multivariable adjustment, quit-smokers showed a higher risk of dementia than never smokers (hazard ratio [HR] 1.16, 95% confidence interval [CI] 1.03–1.32), but the risk was significantly decreased when compared to current smokers (HR 0.83, 95% CI 0.72–0.95). Alzheimer's dementia and vascular dementia showed consistent results as main (Figure).

Conclusion

All types of smoking were associated with a significantly higher risk of dementia in patients with new-onset AF. Smoking cessation after AF diagnosis showed a lower risk of dementia compared to patients smoking persistently. These findings may support the promotion of smoking cessation to lower the risk of dementia in patients with new-onset AF.

Funding Acknowledgement

Type of funding sources: None.

Flavobacterium dauae sp. nov., isolated from rhizosphere soil of a tomato plant

A bacterial strain, designated TCH3-2^T, was isolated from the rhizosphere of tomato plant grown at Dong-A University Agricultural Experiment Station, Republic of Korea. The strain was Gram-stain-negative, obligate aerobic, orange yellow-coloured, motile by gliding and short rod-shaped. Strain TCH3-2 ^T only grew on 1/2 tryptic soy agar and Luria-Bertani agar among the media tested, with optimum growth at 28 °C and pH 7. Salt of 1 % NaCl was necessary to support the growth of TCH3-2^T. Strain TCH3-2^T produced flexirubin-type pigments. The predominant cellular fatty acids were iso-C_15 : 0 (55.6 %), iso-C_17 : 0 3-OH (17.9 %), summed feature 9 (comprising C_16 : 0 10-methyl and/or iso-C_17 : 1  ω9c; 10.5 %), iso-C_15 : 0 3-OH (4.8 %) and anteiso-C_15 : 0 (2.3 %). The major menaquinone was menaquinone-6 and the major polar lipids were phosphatidylethanolamine, five unknown aminolipids and three unknown lipids. Phylogenetic analysis based on 16S rRNA sequences indicated that TCH3-2^T was closely related to Flavobacterium ummariense DS-12^T (95.16 %), Flavobacterium marinum SW105^T (95.14 %) and Flavobacterium viscosus YIM 102796^T (94.54 %). The draft genome of TCH3-2^T comprised ca. 2.8 Mb with a G+C content of 34.61 mol%. The average nucleotide identity and digital DNA-DNA hybridization values between TCH3-2^T and closely related Flavobacterium species showed that it belongs to a distinct species. Furthermore, the results of morphological, physiological and biochemical tests allowed further phenotypic differentiation of TCH3-2^T from its closest relatives. Thus, chemotaxonomic characteristics together with phylogenetic affiliation illustrate that TCH3-2^T represents a novel species of the genus Flavobacterium, for which the name Flavobacterium dauae sp. nov. (type strain TCH3-2^T=KACC 19054^T=JCM 34025^T) is proposed.

Measuring the structure and equation of state of polyethylene terephthalate at megabar pressures

We present structure and equation of state (EOS) measurements of biaxially orientated polyethylene terephthalate (PET, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$({\hbox {C}}_{10} {\hbox {H}}_8 {\hbox {O}}_4)_n$$\end{document}(C10H8O4)n, also called mylar) shock-compressed to (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$155 \pm 20$$\end{document}155±20) GPa and (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$6000 \pm 1000$$\end{document}6000±1000) K using in situ X-ray diffraction, Doppler velocimetry, and optical pyrometry. Comparing to density functional theory molecular dynamics (DFT-MD) simulations, we find a highly correlated liquid at conditions differing from predictions by some equations of state tables, which underlines the influence of complex chemical interactions in this regime. EOS calculations from ab initio DFT-MD simulations and shock Hugoniot measurements of density, pressure and temperature confirm the discrepancy to these tables and present an experimentally benchmarked correction to the description of PET as an exemplary material to represent the mixture of light elements at planetary interior conditions.

2D monochromatic x-ray imaging for beam monitoring of an x-ray free electron laser and a high-power femtosecond laser

In pump-probe experiments with an X-ray Free Electron Laser (XFEL) and a high-power optical laser, spatial overlap of the two beams must be ensured to probe a pumped area with the x-ray beam. A beam monitoring diagnostic is particularly important in short-pulse laser experiments where a tightly focused beam is required to achieve a relativistic laser intensity for generation of energetic particles. Here, we report the demonstration of on-shot beam pointing measurements of an XFEL and a terawatt class femtosecond laser using 2D monochromatic Kα imaging at the Matter in Extreme Conditions end-station of the Linac Coherent Light Source. A thin solid titanium foil was irradiated by a 25-TW laser for fast electron isochoric heating, while a 7.0 keV XFEL beam was used to probe the laser-heated region. Using a spherical crystal imager (SCI), the beam overlap was examined by measuring 4.51 keV Kα x rays produced by laser-accelerated fast electrons and the x-ray beam. Measurements were made for XFEL-only at various focus lens positions, laser-only, and two-beam shots. Successful beam overlapping was observed on ∼58% of all two-beam shots for 10 μm thick samples. It is found that large spatial offsets of laser-induced Kα spots are attributed to imprecise target positioning rather than shot-to-shot laser pointing variations. By applying the Kα measurements to x-ray Thomson scattering measurements, we found an optimum x-ray beam spot size that maximizes scattering signals. Monochromatic x-ray imaging with the SCI could be used as an on-shot beam pointing monitor for XFEL-laser or multiple short-pulse laser experiments.

Probing the Electronic Structure of Warm Dense Nickel via Resonant Inelastic X-Ray Scattering

The development of bright free-electron lasers (FEL) has revolutionized our ability to create and study matter in the high-energy-density (HED) regime. Current diagnostic techniques have been successful in yielding information on fundamental thermodynamic plasma properties, but provide only limited or indirect information on the detailed quantum structure of these systems, and on how it is affected by ionization dynamics. Here we show how the valence electronic structure of solid-density nickel, heated to temperatures of around 10 of eV on femtosecond timescales, can be probed by single-shot resonant inelastic x-ray scattering (RIXS) at the Linac Coherent Light Source FEL. The RIXS spectrum provides a wealth of information on the HED system that goes well beyond what can be extracted from x-ray absorption or emission spectroscopy alone, and is particularly well suited to time-resolved studies of electronic-structure dynamics.

Association of low skeletal muscle mass with the presence of advanced colorectal neoplasm: integrative analysis using three skeletal muscle mass indices

AIM

This study aimed to evaluate an association between colorectal neoplasm (CRN) and skeletal muscle mass using three widely accepted skeletal muscle mass indices (SMIs) in a large population at average risk.

METHOD

We performed a cross-sectional study using a screening colonoscopy database of 33 958 asymptomatic subjects aged 40-75 years. Appendicular skeletal muscle mass (ASM) was measured using a bioelectrical impedance analyser. ASM adjusted for height squared (ASM/ht² ), weight (ASM/wt) and body mass index (ASM/BMI) were used as indices for muscle mass. Logistic regression models were used to evaluate the association between SMIs and CRN.

RESULTS

In a multivariable-adjusted model, the risk of an advanced CRN increased linearly with decreasing quartiles for all three SMIs. The adjusted odds ratios (ORs) for advanced CRN in quartiles 1, 2 and 3 of ASM/wt compared with that in quartile 4 were 1.279, 1.196 and 1.179, respectively (P_trend  = 0.017); for ASM/BMI, ORs were 1.307, 1.144 and 1.091, respectively (P_trend  = 0.002); and for ASM/ht² , ORs were 1.342, 1.169 and 1.062, respectively (P_trend  = 0.002). The risk of distally located advanced CRN was higher in quartile 1 than in quartile 4 for all three SMIs (ASM/wt, OR = 1.356; ASM/BMI, OR = 1.383; ASM/ht² , OR = 1.430).

CONCLUSION

Our study demonstrated that low skeletal muscle mass was consistently associated with the presence of advanced CRN in a population at average risk regardless of the operational definition of the SMI, and it was particularly associated with distal advanced CRN.

Contribution of the murI Gene Encoding Glutamate Racemase in the Motility and Virulence of Ralstonia solanacearum

Bacterial traits for virulence of Ralstonia solanacearum causing lethal wilt in plants were extensively studied but are not yet fully understood. Other than the known virulence factors of Ralstonia solanacearum, this study aimed to identify the novel gene(s) contributing to bacterial virulence of R. solanacearum. Among the transposon-inserted mutants that were previously generated, we selected mutant SL341F12 strain produced exopolysaccharide equivalent to wild type strain but showed reduced virulence compared to wild type. In this mutant, a transposon was found to disrupt the murI gene encoding glutamate racemase which converts L-glutamate to D-glutamate. SL341F12 lost its motility, and its virulence in the tomato plant was markedly diminished compared to that of the wild type. The altered phenotypes of SL341F12 were restored by introducing a full-length murI gene. The expression of genes required for flagella assembly was significantly reduced in SL341F12 compared to that of the wild type or complemented strain, indicating that the loss of bacterial motility in the mutant was due to reduced flagella assembly. A dramatic reduction of the mutant population compared to its wild type was apparent in planta (i.e., root) than its wild type but not in soil and rhizosphere. This may contribute to the impaired virulence in the mutant strain. Accordingly, we concluded that murI in R. solanacearum may be involved in controlling flagella assembly and consequently, the mutation affects bacterial motility and virulence.

The effects of hidden female smokers on the association between smoking and chronic obstructive pulmonary disease in Korean adults

OBJECTIVE

Smoking is an important causative factor of chronic obstructive pulmonary disease (COPD), and females are considered more susceptible to the effects of smoking than males. However, in previous Korean studies, the effects of sex differences on the association between smoking and COPD have been controversial. In this study, the effects of sex differences on the association between smoking and COPD and the effects of female hidden smokers on that association in Korean adults were investigated.

METHODS

Data were acquired from the Korea National Health and Nutrition Examination Surveys (KNHANES).

RESULTS

The multivariate logistic regression analysis showed that self-reported smoking status for ex-smoker and current smoker correlated with COPD (odds ratio, OR: 1.67 and OR: 2.41, respectively). Self-reported smoking status for ex-smoker and current smoker correlated with COPD in men (OR: 1.61, OR: 2.43, respectively). Female self-reported current smoking status correlated with COPD (OR: 2.52), but female ex-smoker status was not significantly correlated with COPD. The ratios of cotinine-verified to self-reported smoking rates were 1.95 for women and 1.07 for men.

CONCLUSION

The results of this study were that sex differences might affect the association between COPD and smoking and that female hidden smoking might affect the association between smoking and COPD in Korean adults.

Rate of colorectal neoplasia in patients with Hodgkin lymphoma

AIM

Survivors of Hodgkin lymphoma (HL) are at increased risk of breast, lung, thyroid, stomach, pancreatic and colon cancer. There is limited information on the utility of endoscopic screening for colon cancer. We aimed to describe the adenoma detection rate (ADR) in patients with HL to determine the appropriate timing of colonoscopy screening.

METHOD

We retrospectively studied patients with HL who underwent colonoscopy between 2000 and 2017.

RESULTS

A total of 251 patients underwent colonoscopy. Eighty (32%) patients had 151 colonic polyps. Thirty per cent of the polyps exhibited high-grade dysplasia, and invasive colon adenocarcinoma was found in 10 patients. Patients with the nodular sclerosing subtype of HL had a significantly lower ADR than others (P = 0.002). The ADR was 5% in patients younger than 35 years (n = 64), 23% in patients between 35 and 40 years of age (n = 22), 39% in patients between 40 and 50 years of age (n = 51) and 46% in patients older than 50 years (n = 114).

Tooth Loss Predicts Myocardial Infarction, Heart Failure, Stroke, and Death

We investigated whether oral health, represented by missing teeth, was associated with an increased risk of cardiovascular disease, including myocardial infarction (MI), heart failure (HF), stroke, and all-cause mortality. Subjects who underwent routine dental examinations and health checkups provided by the Korean National Health Insurance from 2007 to 2008 ( n = 4,440,970) were followed up for incident MI, HF, stroke, and death until 2016. During follow-up of 7.56 y, 68,063 (1.5%) subjects died, and 31,868 (0.7%) were admitted for MI, 22,637 (0.5%) for HF, and 30,941 (0.7%) for stroke. Cardiovascular events and mortality increased in proportion to tooth loss. Tooth loss was an independent risk factor for cardiovascular events after multivariable analysis adjusted for cardiovascular risk, behavioral, and income factors. Each missing tooth was associated with an approximately 1% increase in MI (HR, 1.010; 95% CI, 1.007 to 1.014), 1.5% increase in HF (HR, 1.016; 95% CI, 1.013 to 1.019) and stroke (HR, 1.015; 95% CI, 1.012 to 1.018), and 2% increase in mortality (HR, 1.022; 95% CI, 1.020 to 1.023). Having ≥5 missing teeth substantially increased risk for cardiovascular outcomes, and even a small number of missing teeth (1 to 4) was associated with an increased risk for MI, stroke, and death. This association was consistent in subgroup analyses and especially strong among the younger subjects (age <65 y) and those with periodontitis. In this large Korean nationwide cohort study, we found that tooth loss showed a dose-dependent association with incident MI, HF, ischemic stroke, and all-cause death and was a good predictor of cardiovascular outcome. In clinical practice, the number of missing teeth can aid physicians in discriminating patients with a higher cardiovascular risk.

Alteration of Bacterial Wilt Resistance in Tomato Plant by Microbiota Transplant

Plant-associated microbiota plays an important role in plant disease resistance. Bacterial wilt resistance of tomato is a function of the quantitative trait of tomato plants; however, the mechanism underlying quantitative resistance is unexplored. In this study, we hypothesized that rhizosphere microbiota affects the resistance of tomato plants against soil-borne bacterial wilt caused by Ralstonia solanacearum. This hypothesis was tested using a tomato cultivar grown in a defined soil with various microbiota transplants. The bacterial wilt-resistant Hawaii 7996 tomato cultivar exhibited marked suppression and induction of disease severity after treatment with upland soil-derived and forest soil-derived microbiotas, respectively, whereas the transplants did not affect the disease severity in the susceptible tomato cultivar Moneymaker. The differential resistance of Hawaii 7996 to bacterial wilt was abolished by diluted or heat-killed microbiota transplantation. Microbial community analysis revealed the transplant-specific distinct community structure in the tomato rhizosphere and the significant enrichment of specific microbial operational taxonomic units (OTUs) in the rhizosphere of the upland soil microbiota-treated Hawaii 7996. These results suggest that the specific transplanted microbiota alters the bacterial wilt resistance in the resistant cultivar potentially through a priority effect.

Nonisentropic Release of a Shocked Solid

We present molecular dynamics simulations of shock and release in micron-scale tantalum crystals that exhibit postbreakout temperatures far exceeding those expected under the standard assumption of isentropic release. We show via an energy-budget analysis that this is due to plastic-work heating from material strength that largely counters thermoelastic cooling. The simulations are corroborated by experiments where the release temperatures of laser-shocked tantalum foils are deduced from their thermal strains via in situ x-ray diffraction and are found to be close to those behind the shock.

Prognostic value of tumor-infiltrating lymphocytes in patients with early-stage triple-negative breast cancers (TNBC) who did not receive adjuvant chemotherapy

BACKGROUND

Although stromal tumor-infiltrating lymphocytes (sTILs) have been considered an important prognostic factor in early-stage triple-negative breast cancer (TNBC), there have been limited data on their prognostic value in the absence of adjuvant chemotherapy.

PATIENTS AND METHODS

A pooled analysis was carried out using four cohorts of TNBC patients not treated with chemotherapy. sTILs were evaluated in the most representative tumoral block of surgical specimens. Cox proportional hazards regression models were used for invasive disease-free survival (iDFS), distant disease-free survival (D-DFS), and overall survival (OS), fitting sTILs as a continuous variable adjusted for clinicopathologic factors.

RESULTS

We analyzed individual data of 476 patients from 4 centers diagnosed between 1989 and 2015. Their median age was 64 years. The median tumor size was 1.6 cm and 83% were node-negative. The median level of sTILs was 10% (Q1-Q3, 4%-30%). Higher grade was associated with higher sTILs (P < 10-3). During follow-up, 107 deaths, and 173 and 118 events for iDFS and D-DFS were observed, respectively. In the multivariable analysis, sTILs obtained an independent prognostic value for all end points (likelihood ratio χ2 = 7.14 for iDFS; P < 10-2; χ2 = 9.63 for D-DFS, P < 10-2; χ2 = 5.96 for OS, P = 0.015). Each 10% increment in sTILs corresponded to a hazard ratio of 0.90 [95% confidence interval (CI) 0.82 - 0.97] for iDFS, 0.86 (95% CI 0.77 - 0.95) for D-DFS, and 0.88 (95% CI 0.79 - 0.98) for OS, respectively. In patients with pathological stage I tumors with sTILs ≥30% (n = 74), 5-year iDFS was 91% (95% CI 84% to 96%), D-DFS was 97% (95% CI 93% to 100%), and OS was 98% (95% CI 95% to 100%).

CONCLUSION

sTILs add important prognostic information in systemically untreated early-stage TNBC patients. Notably, sTILs can identify a subset of stage I TNBC patients with an excellent prognosis without adjuvant chemotherapy.

Surgical outcomes of tympanoplasty using a sterile acellular dermal allograft: a prospective randomised controlled study

Acellular human dermal allografts have been shown to be effective for soft-tissue implantation. We compared treatment outcomes of tympanoplasty using tragal perichondrium and acellular human dermal allograft (MegaDerm^®). In a prospective randomised controlled study, 60 patients scheduled to undergo tympanoplasty were randomly assigned to the autologous tragal perichondrium group (n = 33) or acellular human dermal allograft group (n = 27). Postoperative hearing gain, graft success rate at 1 and 6 months and operation times were compared between groups. Graft success rate, defined as the complete closure of tympanic membrane perforation, did not show any significant intergroup difference (75.8% vs 85.2%, p = 0.519). Air conduction thresholds and air-bone gaps showed significant improvements in both groups; from 38.7 ± 15.9 dB to 30.2 ± 15.6 dB (p < 0.001) and from 17.8 ± 7.3 dB to 11.5 ± 7.0 (p = 0.001) in the autologous tragal perichondrium group, and from 30.4 ± 12.2 dB to 24.5 ± 13.0 dB (p = 0.006) and from 14.3 ± 5.1 dB to 7.6 ± 4.6 dB (p < 0.001) in the acellular human dermal allograft group. The amount of hearing gain (p = 0.31) and closure of air-bone gap (p = 0.863) were not meaningfully different between groups. The mean operation time was significantly lower in the acellular human dermal allograft group (35.2 min vs 27.4 min, p = 0.039). In this prospective randomised controlled study, acellular human dermal allograft was shown to be an effective alternative to tragal perichondrium, with similar graft success rates and postoperative hearing results, but with reduced operation times.

Factors associated with HIV/AIDS-related stigma and discrimination by medical professionals in Korea: A survey of infectious disease specialists in Korea

Objectives

This study sought to identify factors associated with this discrimination by medical professionals in Korea.

Subjects and Methods

This study was a cross-sectional survey. We conducted web-based surveys against infectious disease specialists and infectious disease nurse. We evaluated the frequency of human immunodeficiency virus (HIV)/AIDS-related discrimination by medical professionals by health service type on the 5-point scale. We identified the association between several factors and HIV/AIDS-related stigma and discrimination by medical professionals on the 5-point scale.

Results

A total of 81 experts, 57 infectious disease specialists (approximately 27% of all infectious disease specialists in Korea) and 24 infectious disease nurse practitioners, participated in this study. The frequency of stigma and discrimination increased significantly when invasive treatment included both outpatient and inpatient services (both P < 0.05). Medical professional's preconceptions, fear of infection, and lack of knowledge have an association with HIV/AIDS-related stigma and discrimination by medical professionals.

Conclusion

HIV/AIDS-related stigma and discrimination by medical professionals in Korea might be associated with factors related to the fear of medical professionals.

Identification of Phase Transitions and Metastability in Dynamically Compressed Antimony Using Ultrafast X-Ray Diffraction

Ultrafast x-ray diffraction at the LCLS x-ray free electron laser has been used to resolve the structural behavior of antimony under shock compression to 59 GPa. Antimony is seen to transform to the incommensurate, host-guest phase Sb-II at ∼11  GPa, which forms on nanosecond timescales with ordered guest-atom chains. The high-pressure bcc phase Sb-III is observed above ∼15  GPa, some 8 GPa lower than in static compression studies, and mixed Sb-III/liquid diffraction are obtained between 38 and 59 GPa. An additional phase which does not exist under static compression, Sb-I^{'}, is also observed between 8 and 12 GPa, beyond the normal stability field of Sb-I, and resembles Sb-I with a resolved Peierls distortion. The incommensurate Sb-II high-pressure phase can be recovered metastably on release to ambient pressure, where it is stable for more than 10 ns.

A Novel Collateral Imaging Method Derived from Time-Resolved Dynamic Contrast-Enhanced MR Angiography in Acute Ischemic Stroke: A Pilot Study

BACKGROUND AND PURPOSE

Assessment of the collateral status has been emphasized for appropriate treatment decisions in patients with acute ischemic stroke. The purpose of this study was to introduce a multiphase MRA collateral imaging method (collateral map) derived from time-resolved dynamic contrast-enhanced MRA and to verify the value of the multiphase MRA collateral map in acute ischemic stroke by comparing it with the multiphase collateral imaging method (MRP collateral map) derived from dynamic susceptibility contrast-enhanced MR perfusion.

MATERIALS AND METHODS

From a prospectively maintained registry of acute ischemic stroke, MR imaging data of patients with acute ischemic stroke caused by steno-occlusive lesions of the unilateral ICA and/or the M1 segment of the MCA were analyzed. We generated collateral maps using dynamic signals from dynamic contrast-enhanced MRA and DSC-MRP using a Matlab-based in-house program and graded the collateral scores of the multiphase MRA collateral map and the MRP collateral map independently. Interobserver reliabilities and intermethod agreement between both collateral maps for collateral grading were tested.

RESULTS

Seventy-one paired multiphase MRA and MRP collateral maps from 67 patients were analyzed. The interobserver reliabilities for collateral grading using multiphase MRA or MRP collateral maps were excellent (weighted κ = 0.964 and 0.956, respectively). The agreement between both collateral maps was also excellent (weighted κ = 0.884; 95% confidence interval, 0.819-0.949).

CONCLUSIONS

We demonstrated that the dynamic signals of dynamic contrast-enhanced MRA could be used to generate multiphase collateral images and showed the possibility of the multiphase MRA collateral map as a useful collateral imaging method in acute ischemic stroke.

Abstract P4-02-05: Apocrine morphology and LAR molecular subtype predict prognosis of TNBC patients with residual disease after neoadjuvant chemotherapy

Background: TNBC molecular subtype classification updated by Lehmann et al. includes 4 subtypes: basal-like 1 and 2 (BL1), (BL2), mesenchymal (M), and luminal androgen receptor (LAR), and as a modifier of these subtypes, an Immunomodulatory (IM) gene expression signature. However, molecular subtypes have not been linked to morphological features of TNBC. Apocrine carcinoma has been proposed as a TNBC category that expresses androgen receptor. LAR-subtype TNBC has a poor response to neoadjuvant systemic therapy (NST). We hypothesized that defining the apocrine-featured TNBC by morphology and molecular subtype predict the prognosis of patients with residual disease after NST. Methods: We created the Pan-Pacific TNBC Consortium dataset, which contains paired samples of matched pre and post-NST TNBC tumors from 4 institutions. All patients received NST and didn't have a pathological complete response (pCR). Three pathologists examined hematoxylin and eosin-stained slides of 86 pre-NST samples and determined (1) the presence of apocrine differentiation, (2) the level of tumor-infiltrating lymphocytes (TILs), (3) the histological grade (HG), and (4) the rate of necrosis. These morphological features were compared among the subtypes. For a sample to be considered apocrine positive, apocrine differentiation had to be identified by 2 or more pathologists. Fisher's exact test was used to test the association of subtypes and morphological features. The log-rank test was used to compare disease-free survival (DFS). Results: Twelve of 24 (50%) apocrine-positive tumor samples were LAR subtype, and12 of 17 (70%) LAR-subtype tumor samples exhibited apocrine differentiation. The other subtypes showed following: BL1, 11/44 (25%); BL2, 0/7 (0%); M, 1/10 (10%); unclassified, 0/8 (0%). The median follow-up time was 22 months. In all populations, 2-year DFS rates were higher in patients with apocrine-positive tumors than in those whose tumors did not exhibit apocrine differentiation (P = .027; 2-year DFS, 85% vs 54%). The LAR subtype was also associated with lower HG, although LAR tumors had a similar prognosis to the other subtypes. In the combined analysis of subtypes and apocrine differentiation, patients with apocrine-positive LAR tumors had a higher 2-year DFS rate than did those with apocrine-negative LAR tumors (P = .044; 2-year DFS, 88% vs. 30%). However, patients with apocrine-positive BL1 tumors had no better DFS than did those with apocrine-negative BL1 tumors (P = .133). TIL levels and the presence of the IM signature were positively associated (P = .01), and apocrine differentiation positivity tended to be negatively associated with TIL level (P = .06). Neither TIL level nor IM signature was associated with survival. Conclusion: Apocrine differentiation was associated with the LAR subtype of TNBC and better prognosis in patients who did not have a pCR. The LAR subtype alone did not predict DFS; however, LAR tumors with apocrine differentiation had a better prognosis than did LAR tumors without apocrine differentiation. Using a combination of morphologic and genomic testing may be helpful in determining the prognosis of patients with apocrine-positive TNBC tumors who have residual disease after NST.

Citation Format: Masuda H, Miura S, Harano K, Wang Y, Hirota Y, Matsunaga Y, Lim B, Lucci A, Parinyanitikul N, Lee HJ, Gong G, Rao A, Seitz RS, Morris SW, Hout DR, Nakamura S, Tripathy D, Harada O, Krishnamurthy S, Ueno NT. Apocrine morphology and LAR molecular subtype predict prognosis of TNBC patients with residual disease after neoadjuvant chemotherapy [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-02-05.

Abstract P2-07-10: Not presented

This abstract was not presented at the conference.

Citation Format: Lee H-B, Kim KE, Ju YW, Jung J-G, Ryu H-S, Lee SB, Lee JW, Lee HJ, Kim M-S, Kwon S, Kim J, Kim C, Moon H-G, Noh D-Y, Ahn S-H, Park I-A, Kim S, Yoon S, Kim A, Han W. Not presented [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-07-10.

Abstract P4-01-11: Genomic alterations of cell-free DNA in early breast cancer patients with recurrence

Cell-free DNA (cfDNA), as a non-invasive strategy, provides substantial benefit to overcome tumor heterogeneity. Surveillance of recurrence after standard treatment in early breast cancer (BC) using cfDNA, enables to detect minimal residual disease (MRD), also to identify genomic alterations driving recurrences. We aimed to assess the role of cfDNA in detecting MRD by investigating genomic alterations of 1)primary, recurred tumor and 2)cfDNA at time of recurrence using deep targeted sequencing. Fifty-four early BC patients were enrolled prospectively between 2014 and 2017 at time of recurrence. Median disease free interval was 28.5 months (rage 6.2-49.8). 62.7% (32/51) were hormone receptor (HR) positive (28 HRpos/HER2neg, 4 HRpos/HER2pos), 11.8% (6/51) were HRneg/HER2pos and 25.5% (13/51) were triple negative BCs. 59.3% (32/54) patients developed loco-regional recurrence (15 local recurrence only, 13 regional only, 4 with both) and distant metastasis was observed among 40.7% (22/54) patients. Cell-free DNA was extracted from 5cc blood at time of recurrence. Deep targeted sequencing was performed using customized NGS panel –encompassing 426 cancer-related target coding region, 242 fusion and amplification-related region- of cfDNA and FFPE(formalin fixed paraffin embedded) tumor samples archived from surgical resection or biopsy. Deep targeted sequencing data was successfully performed in 72.1% (31/43) plasma samples and sequencing yield was significantly lower when stored for more than 2yrs (46.2% vs 83.3%).

Mutations of cfDNA and tumor (primary, recurred) were analyzed. Mean sequencing depth of cfDNA and FFPE were x425.7 and x777.6 respectively. Median number of pathogenic mutations found in primary tumor, cfDNA and recurred tumor were 27(range 12-99), 25(range 8-85) and 9(range 0-23). Among mutations found in primary tumor, 27.4% were shared mutations (range 8.1%-72.7%) with recurred tumor and 26.1% were shared mutations (range 4.7%-69.2%) observed in cfDNA sample. Among mutations found in recurred tumor, 40.9% were observed in cfDNA (range 17.7-87.5%). In primary tumor, median number of mutations with allelic fraction (MAF)&gt;10% were 12 (range 4-21) and at least one mutation was found in cfDNA at time of recurrence. Among mutations with MAF&gt;10%, 59.4% and 69.1% were found in cfDNA and recurred tumor. Known oncogenic mutations of PIK3CA, TP53, GATA3, AKT1, ESR1, RELN, ERBB2, ERBB3, BRCA1 mutation were found. PIK3CA gene (p.H1047R) was found in two cases both in primary tumor and cfDNA at recurrence (MAF 11.4% vs 5.3% and 12.3% vs 15.4%) suggesting de novo driver mutation. One patient developed regional recurrence during adjuvant aromatase inhibitor with ESR1 V392I mutation in both cfDNA and recurred tumor (MAF 48.1 and 54.5%), while another patient's recurred tumor during aromatase inhibitor harbored ESR1 D538G mutation exclusively in recurred tumor with MAF &lt;1%. Both patients had no ESR1 hotpot mutation in primary tumor.

Our data showed sequencing yield of 83.3% in plasma samples within 2yr. Pathogenic mutations in primary tumor, especially when MAF&gt;10%, half of them was observed in cfDNA at time of recurrence. ESR1 mutation should be included in cfDNA surveillance for patients undergoing endocrine therapy even absent in primary tumor.

Citation Format: Kim J, Jo WK, Kim KY, Kim BJ, Lee SB, Lee HJ, Yu JH, Kim HJ, Chung IY, Ko BS, Kim S-B, Jung KH, Ahn JH, Chang S, Lee JW, Son BH, Ahn SH. Genomic alterations of cell-free DNA in early breast cancer patients with recurrence [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-01-11.

Host nuclear factor erythroid 2-related factor-2 defense system determines the outcome of dextran sulfate sodium-induced colitis in mice

Administration of dextran sulfate sodium (DSS) in drinking water led to significant bout of colitis simulating ulcerative colitis of human. However, colitis usually developed 5 - 7 days after DSS administration. Therefore, we hypothesized host defense system might protect colitis up to 5 days of DSS administration. 2.5% DSS-induced colitis were administered to C57BL/6 mice and sequential measurements of pathology, cyclooxygenase-2 (COX-2), nuclear factor-κB (NF-κB), heme oxygenase-1 (HO-1), NADPH quinone oxidoreductase-1 (NQO1), γ-glutamylcysteine synthetase (γ-GCS), nuclear factor erythroid 2-related factor-2 (Nrf2), and keap1 were done at 2, 6, 12, 24, 48, 96, 120, and 168 hour of DSS administration, respectively. DSS-induced colitis was repeated in either COX-2^-/- or Nrf2^-/- mice. On serial pathological analysis, significant colitis was noted after 120 h of DSS administration, during which both activations of COX-2/NF-κB and HO-1/Nrf2 were noted. Nrf2 activations after keap1 inactivation led to significant increases in HO-1 after 168 hours of DSS administration, when NF-κB nuclear translocation was noted. Significantly attenuated colitis was noted in DSS-challenged COX-2^-/- mice, in which the levels of HO-1 were significantly decreased compared to DSS-challenged WT littermates (p < 0.01), while the levels of NQO1 were significantly increased. On DSS administration to Nrf2^-/- mice, colitis was significantly aggravated (p < 0.01), in which the expressions of COX-2 as well as expressions of HO-1 and γ-GCS were significantly increased (p < 0.01). Reciprocal activations of inflammatory and antioxidative defense signaling after DSS administration might be prerequisite to make intestinal homeostasis and host defense Nrf2 system can determine colitis.

Predicting extinction phenotype to optimize fear reduction

Fear conditioning is widely employed to study dysregulations of the fear system. The repeated presentation of a conditioned stimulus in the absence of a reinforcer leads to a decrease in fear responding-a phenomenon known as extinction. From a translational perspective, identifying whether an individual might respond well to extinction prior to intervention could prove important to treatment outcomes. Here, we test the hypothesis that CO₂ reactivity predicts extinction phenotype in rats, and that variability in CO₂ reactivity as well as extinction long-term memory (LTM) significantly predicts orexin activity in the lateral hypothalamus (LH). Our results validate a rat model of CO₂ reactivity and show that subcomponents of behavioral reactivity following acute CO₂ exposure explain a significant portion of the variance in extinction LTM. Furthermore, we show evidence that variability in CO₂ reactivity is also significantly predictive of orexin activity in the LH, and that orexin activity, in turn, significantly accounts for LTM variance. Our findings open the possibility that we may be able to use CO₂ reactivity as a screening tool to determine if individuals are good candidates for an extinction/exposure-based approach.

Extinction to amphetamine-associated context in female rats is dependent upon conditioned orienting

RATIONALE

Females are considered more susceptible to the reinforcing effects of drugs and subsequently at increased risk for drug abuse and relapse after treatment. Estrogen is known to facilitate drug effects in females. However, other factors which contribute to the incidence of drug abuse are important to identify in order to recognize early risk factors and develop effective prevention and treatment schemes. Cue-directed behavior (aka sign tracking) has been implicated as a behavioral phenotype which identifies populations susceptible to drug abuse, partly due to its association with impulsivity and heightened dopamine function.

OBJECTIVES AND METHODS

In this study, we investigate the viability of conditioned orienting (a form of cue-directed behavior) as a potential phenotype which predicts drug proclivity in female rats. In addition, we examine any influence endogenous female hormones across the estrous cycle may have on conditioned orienting and drug proclivity.

RESULTS AND CONCLUSIONS

Utilizing an amphetamine-conditioned place preference task, results suggest that the orienting phenotype is an effective predictor of drug proclivity in females. Rats exhibiting enhanced orienting behavior show more robust preference for an amphetamine-associated context and are more resistant to extinction of this preference than nonorienting counterparts. Furthermore, both conditioned orienting behavior and conditioned place preference are minimally influenced by the estrous cycle.

Femtosecond diffraction studies of solid and liquid phase changes in shock-compressed bismuth

Bismuth has long been a prototypical system for investigating phase transformations and melting at high pressure. Despite decades of experimental study, however, the lattice-level response of Bi to rapid (shock) compression and the relationship between structures occurring dynamically and those observed during slow (static) compression, are still not clearly understood. We have determined the structural response of shock-compressed Bi to 68 GPa using femtosecond X-ray diffraction, thereby revealing the phase transition sequence and equation-of-state in unprecedented detail for the first time. We show that shocked-Bi exhibits a marked departure from equilibrium behavior - the incommensurate Bi-III phase is not observed, but rather a new metastable phase, and the Bi-V phase is formed at significantly lower pressures compared to static compression studies. We also directly measure structural changes in a shocked liquid for the first time. These observations reveal new behaviour in the solid and liquid phases of a shocked material and give important insights into the validity of comparing static and dynamic datasets.

Rhizosphere microbiome structure alters to enable wilt resistance in tomato

Tomato variety Hawaii 7996 is resistant to the soil-borne pathogen Ralstonia solanacearum, whereas the Moneymaker variety is susceptible to the pathogen. To evaluate whether plant-associated microorganisms have a role in disease resistance, we analyzed the rhizosphere microbiomes of both varieties in a mesocosm experiment. Microbiome structures differed between the two cultivars. Transplantation of rhizosphere microbiota from resistant plants suppressed disease symptoms in susceptible plants. Comparative analyses of rhizosphere metagenomes from resistant and susceptible plants enabled the identification and assembly of a flavobacterial genome that was far more abundant in the resistant plant rhizosphere microbiome than in that of the susceptible plant. We cultivated this flavobacterium, named TRM1, and found that it could suppress R. solanacearum-disease development in a susceptible plant in pot experiments. Our findings reveal a role for native microbiota in protecting plants from microbial pathogens, and our approach charts a path toward the development of probiotics to ameliorate plant diseases.

Setup for meV-resolution inelastic X-ray scattering measurements and X-ray diffraction at the Matter in Extreme Conditions endstation at the Linac Coherent Light Source

We describe a setup for performing inelastic X-ray scattering and X-ray diffraction measurements at the Matter in Extreme Conditions (MEC) endstation of the Linac Coherent Light Source. This technique is capable of performing high-, meV-resolution measurements of dynamic ion features in both crystalline and non-crystalline materials. A four-bounce silicon (533) monochromator was used in conjunction with three silicon (533) diced crystal analyzers to provide an energy resolution of ∼50 meV over a range of ∼500 meV in single shot measurements. In addition to the instrument resolution function, we demonstrate the measurement of longitudinal acoustic phonon modes in polycrystalline diamond. Furthermore, this setup may be combined with the high intensity laser drivers available at MEC to create warm dense matter and subsequently measure ion acoustic modes.

A high-resolution anorectal manometry parameter based on integrated pressurized volume: A study based on 204 male patients with constipation and 26 controls

BACKGROUND

Conventional anorectal manometric parameters based on linear waves cannot properly predict balloon expulsion (BE) time. We aimed to determine the correlation between integrated pressurized volume (IPV) parameters during simulated evacuation (SE) and BE time in healthy individuals and constipated patients and to assess the correlation between each parameter and symptoms.

METHODS

A total of 230 male participants (including 26 healthy volunteers and 204 chronically constipated patients) underwent high-resolution anorectal manometry (HRAM) and BE tests. The IPV was calculated by multiplying the amplitude, distance, and time from the HRAM profile. Receiver operating characteristic curve (ROC) analysis and partial least square regression (PLSR) were performed.

KEY RESULTS

ROC analysis indicated that the IPV ratio between the upper 1 cm and lower 4 cm of the anal canal was more effective for predicting BE time (area under the curve [AUC]: 0.74, 95% confidence interval [CI]: 0.67-0.80, P < .01) than the conventional anorectal parameters, including defecation index and rectoanal gradient (AUC: 0.60, 95% CI: 0.52-0.67, P = .01). PLSR analysis of a linear combination of IPV parameters yielded an AUC of 0.79. Moreover, the IPV ratio showed a greater clinical correlation with patient symptoms than conventional parameters.

CONCLUSIONS AND INFERENCES

The IPV parameters and the combination of IPV parameters via PLSR were more significantly correlated with BE time than the conventional parameters. Thus, this study presents a useful diagnostic tool for the evaluation of pathophysiologic abnormalities in dyssynergic defecation using IPV and BE time.