[The role of large-scale testing platform in the prevention and control of the COVID-19 pandemic: an empirical study based on a novel numerical model]

Objective: China adopted an unprecedented province-scale quarantine since January 23rd 2020, after the novel coronavirus (COVID-19) broke out in Wuhan in December 2019. Responding to the challenge of limited testing capacity, large-scale (>20 000 tests per day) standardized and fully-automated laboratory (Huo-Yan) was built as an ad-hoc measure. There is so far no empirical data or mathematical model to reveal the impact of the testing capacity improvement since quarantine. Methods: Based on the suspected case data released by the Health Commission of Hubei Province and the daily testing data of Huo-Yan Laboratory, the impact of detection capabilities on the realization of "clearing" and "clearing the day" of supected cases was simulated by establishing a novel non-linear and competitive compartments differential model. Results: Without the establishment of Huo-Yan, the suspected cases would increase by 47% to 33 700, the corresponding cost of quarantine would be doubled, the turning point of the increment of suspected cases and the achievement of "daily settlement" (all newly discovered suspected cases are diagnosed according to the nucleic acid testing result) would be delayed for a whole week and 11 days. If the Huo-Yan Laboratory could ran at its full capacity, the number of suspected cases could start to decrease at least a week earlier, the peak of suspected cases would be reduced by at least 44%, and the quarantine cost could be reduced by more than 72%. Ideally, if a daily testing capacity of 10 500 tests was achieved immediately after the Hubei lockdown, "daily settlement" for all suspected cases could be achieved. Conclusions: Large-scale, standardized clinical testing platform, with nucleic acid testing, high-throughput sequencing, and immunoprotein assessment capabilities, need to be implemented simultaneously in order to maximize the effect of quarantine and minimize the duration and cost of the quarantine. Such infrastructure, for both common times and emergencies, is of great significance for the early prevention and control of infectious diseases.

Growth and saturation of stimulated Raman scattering in two overlapping laser beams

Two-dimensional particle-in-cell simulations are presented of the linear and nonlinear developments of stimulated Raman scattering in two overlapping laser beams. The development of the most unstable mode in the linear stage is consistent with a previous paper [C. Z. Xiao et al., Phys. Plasmas 26, 062109 (2019)PHPAEN1070-664X10.1063/1.5096850] where SL mode (two beams share a common scattered light) is dominant in the overlapping region. This mode is enhanced with plasma density and correlation of beam polarizations. When lasers are cross-polarized, it backs to the single-beam Raman backscattering with weak intensity. Trapping-induced nonlinear frequency shift leads to the saturation of SL mode by detuning the coupling and broadening the spectrum. An interesting result that SL mode becomes stronger as the incidence angle increases is contrary to the theoretical prediction and it is a consequence of less efficient saturation in the nonlinear stage.

Dietary supplementation with Bacillus subtilis DSM 32315 alters the intestinal microbiota and metabolites in weaned piglets

AIM

The study was conducted to investigate the effects of dietary Bacillus subtilis (BS) DSM 32315 on the intestinal microbiota composition and metabolites of weaned pigs.

METHODS AND RESULTS

Sixty-four piglets were allocated to two groups (control and BS), each group including eight replicates with four piglets. Dietary BS DSM 32315 increased (P < 0·05) the abundances of jejunal Leucobacter and Cupriavidus, ileal Thermus, Coprococcus and Bifidobacterium, as well as colonic Succiniclasticum; and increased the concentrations of ileal straight-chain fatty acids, colonic propionate, branched-chain fatty acids (BCFAs), and tyramine, but decreased (P < .05) the colonic indole concentration. The ileal and colonic microbial community structure tended to cluster into two groups. LEfSe analysis identified five microbial biomarkers in jejunum and eight biomarkers in ileum in the BS group, and three biomarkers in colon in the control group. The ileal Bifidobacterium abundance was positively correlated (P < 0·05) with isovalerate concentration, while the colonic Actinobacteria and Lactobacillus abundances were negatively correlated (P < 0·05) with indole concentration.

CONCLUSION

These findings suggest that dietary supplementation with BS DSM 32315 could alter the diversity, composition, and metabolites of intestinal microbiota in weaned piglets.

SIGNIFICANCE AND IMPACT OF THE STUDY

Weaned piglets are often accompanied with impaired gastrointestinal tract and intestinal disorder affecting their growth. This study demonstrated that dietary BS DSM 32315 presented a beneficial role in gut health via regulating intestinal microbiota composition and metabolites.

Temperature-Induced Lifshitz Transition and Possible Excitonic Instability in ZrSiSe

The nodal-line semimetals have attracted immense interest due to the unique electronic structures such as the linear dispersion and the vanishing density of states as the Fermi energy approaching the nodes. Here, we report temperature-dependent transport and scanning tunneling microscopy (spectroscopy) [STM(S)] measurements on nodal-line semimetal ZrSiSe. Our experimental results and theoretical analyses consistently demonstrate that the temperature induces Lifshitz transitions at 80 and 106 K in ZrSiSe, which results in the transport anomalies at the same temperatures. More strikingly, we observe a V-shaped dip structure around Fermi energy from the STS spectrum at low temperature, which can be attributed to co-effect of the spin-orbit coupling and excitonic instability. Our observations indicate the correlation interaction may play an important role in ZrSiSe, which owns the quasi-two-dimensional electronic structures.

Pan-Asian adapted ESMO Clinical Practice Guidelines for the management of patients with early breast cancer: a KSMO-ESMO initiative endorsed by CSCO, ISMPO, JSMO, MOS, SSO and TOS

In view of the planned new edition of the most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of primary breast cancer published in 2015, it was decided at the ESMO Asia Meeting in November 2018, by both the ESMO and the Korean Society of Medical Oncology (KSMO), to convene a special face-to-face guidelines meeting in 2019 in Seoul. The aim was to adapt the latest ESMO 2019 guidelines to take into account the ethnic and geographical differences associated with the treatment of early breast cancer in Asian patients. These guidelines represent the consensus opinions reached by experts in the treatment of patients with early breast cancer representing the oncology societies of Korea (KSMO), China (CSCO), India (ISMPO) Japan (JSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence, and was independent of both the current treatment practices, and the drug availability and reimbursement situations, in the individual participating Asian countries.

The Dopaminergic Polymorphisms in Psychomotor Retardation of Depression: A Pathway-based Imaging Genetics Association Study

Introduction

Several lines of evidence implicate dopamine is involved in the psychomotor retardation (PMR) in major depressive disorder (MDD). Besides, abnormal cerebral blood flow (CBF) of PMR was also found in the cortico-basal ganglia-thalamo-cortical (CBTC) circuitry. We hypothesize that the polymorphisms of the dopaminergic pathway should be associated the abnormal CBF in the CBTC circuitry.

Objective

To investigate the association of the polymorphisms throughout the dopaminergic pathway with the cerebral blood flow (CBF) of PMR in MDD.

Methods

The blood sample of 63 patients (23 PMR, 40 NPMR) were collected for genotyping the dopaminergic polymorphisms (92 SNPs from10 genes). After quality controlling, 15 SNPs in 8 candidate genes were entered into the mass univariate modeling analysis. For the statistical analysis, patients with unqualified fMRI image and unmatched demographic data were ruled out. Consequently 56 patients (23 PMR, 33 NPMR) were taken into the statistical analysis.

Results

Genotype-by PMR associations with the CBF differences predominately distributed in bilateral prefrontal cortex (PFC), temporal cortex, and striatum, the left thalamus, the right primary motor cortex, insular cortex, fusiform gyri, and lingual gyri. There were significant negative correlation between the CBF of the PFC and the PMR severity. However, the CBF of the striatum and the thalamus were positively correlated with the PMR severity.

Conclusions

The polymorphisms of dopaminergic pathway are associated with not only CSTC circuitry, but also some other brain regions involving in cognition and emotion controlling. While the increased CBF of PFC might suppress PMR, the increased CBF of striatum and thalamus adversely aggravate PMR.

Rapid isolation of non-aflatoxigenic Aspergillus flavus strains

In the present study, a method for screening non-aflatoxigenic Aspergillus flavus in soil samples collected from major peanut-growing regions of China was developed. The single colonies were picked and cultured on Aspergillus flavus and parasiticus agar (AFPA). If the reverse side of the colony on AFPA was orange-coloured, it was considered A. flavus or Aspergillus parasiticus. After the genomic DNA of each strain was extracted, 28S rRNA and calmodulin were amplified and sequenced to determine the species. The key gene, aflR, was amplified and digested via polymerase chain reaction-restriction fragment length polymorphism. The aflatoxigenic A. flavus and the non-aflatoxigenic A. flavus and A. parasiticus were distinguished by enzyme digestion of aflR. 156 strains of A. flavus were screened, which consisted of 135 aflatoxigenic and 21 non-aflatoxigenic strains. The aflatoxin producing ability of each strain was confirmed using solid-state fermentation experiments. Using the method developed in the present study, we confirmed that the non-aflatoxigenic A. flavus strains isolated lost their capacity to produce aflatoxins. Considering there could be some alterations in other functional genes, some non-aflatoxigenic strains could be identified inaccurately as aflatoxigenic strains, although that did not occur in the present study. The growth of non-aflatoxigenic A. flavus was observed, and the most rapidly growing non-aflatoxigenic strain was selected for plate confrontation assays and toxic mixed culture experiments. The inhibition rate of non-aflatoxigenic A. flavus against aflatoxigenic A. flavus was 55.4 and 72.6% in potato dextrose agar (PDA) plate and natural soybean medium, respectively. The screened non-aflatoxigenic A. flavus strains provide a microbial resource for biological control of aflatoxin contamination.

Experimental and numerical study of SO2 removal from a CO2/SO2 gas mixture in a Cu-BTC metal organic framework

The mechanism of SO₂ removal from a CO₂/SO₂ gas mixture in a copper benzene-1, 3, 5-tricarboxylate (Cu-BTC) material is investigated at the molecular level by the grand canonical Monte Carlo method. The effects of seven kinds of force-field relationships among CO₂, SO₂ and Cu-BTC on the selectivity for a SO₂/CO₂ gas mixture at different temperatures are studied in detail. The accuracy of the simulation model is validated by the experimental data. The results show that more SO₂ molecules are adsorbed than CO₂, and the electrostatic interactions involving SO₂ are more sensitive to temperature than CO₂ is. The multilayer desorption for SO₂ and CO₂ occurs in large-square channels. The effect of the electrostatic interactions involving SO₂ is stronger than the interactions of CO₂. The forms of CO₂ and SO₂ adsorption in Cu-BTC with electrostatic interactions are Cu²⁺∙∙∙OCO and Cu²⁺∙∙∙OSO, respectively.

Lowering the Schottky barrier height of G/WSSe van der Waals heterostructures by changing the interlayer coupling and applying external biaxial strain

Graphene-based van der Waals (vdW) heterostructures composed of two-dimensional transition metal dichalcogenides (TMDs) and graphene show great potential in the design and manufacture of field effect transistors.

[Expression and mechanism of mast cell activating molecules and their antibodies in allergic rhinitis and nasal polyps]

Objective:To analyze the relationship and mechanism of mast cell with allergic rhinitis and nasal polyps. Method:From January 2018 to June 2018, all the inpatients in Otolaryngology Department were examined by nasal endoscopy and CT before operation. They were divided into three groups: 30 patients with allergic rhinitis（AR group） and 30 patients with nasal polyps（NP group） as the experimental group; 30 patients with nasal septum correction after partial inferior turbinectomy alone as the control group（N group）. Clinical data, peripheral blood and nasal mucosa were collected. The percentage of eosinophils in peripheral blood was detected by automatic hematology analyzer. The levels of anti-IgE antibody, FcεRIα and anti-FcεRIα antibody in serum were detected by ELISA. The levels of serum IgE were detected by velocity scattering turbidimetry. HE was used to observe the histopathological changes in the three groups. Immunohistochemical method was used to analyze the expression of tryptase and FcεRIα in the experimental group and the control group. Result:The percentage of eosinophils, IgE, anti-IgE antibody, FcεRIα and anti-FcεRIα antibodies in AR group were significantly higher than those in control group（P<0.05）; the percentage of eosinophils, FcεRIα and anti-FcεRIα antibodies in NP group were significantly higher than those in healthy control group（P<0.05）. There was no significant difference in IgE and anti-IgE antibodies among three groups（P>0.05）. The eosinophil percentage, IgE and anti-IgE antibody levels in AR group were significantly higher than that in NP group（P<0.05）; there were no differences in FcεRIα and anti-FcεRIα antibody levels between AR group and NP group（P>0.05）; There was no significant difference in eosinophil infiltration between the two groups; The brown tryptase-positive mast cells and FcεRIα-positive mast cells were found in the submucosa and interstitium of nasal mucosa. Conclusion:The high expression of FcεRIα and its antibody in the serum of patients with allergic rhinitis and nasal polyps indicated that this antibody system was involved in the occurrence and development of allergic rhinitis and nasal polyps. Local allergy with mast cells as the core might play an important role in the occurrence and development of nasal polyps. The possible role of mast cells in the formation of nasal polyps and the specific mechanism deserve further study.

2400Early and late effects of cardiac resynchronization therapy in adult congenital heart disease

Background

There are limited data regarding cardiac resynchronization therapy (CRT) in adult congenital heart disease (ACHD).

Purpose

We aimed to assess early and late outcomes of CRT amongst patients with ACHD.

Methods

We retrospectively studied ACHD patients receiving CRT (2004–2017). Clinical and echocardiographic data were analyzed at baseline, early (1.8±0.8 years) and late (4.7±0.8 years) follow-up after CRT.

Results

Fifty-four ACHD patients (median age 46 years, range 18–73 years, 74% male) had CRT (biventricular paced >90%) and were followed for 5.7±3.0 years. Thirty-nine (72%) patients had a systemic left ventricle (LV). Underlying cardiac anatomy included left ventricular outflow tract lesions (n=17; 32%), tetralogy of Fallot (n=11; 20%), right ventricular outflow tract lesions (n=5; 9%), atrioventricular septal defects (n=5; 9%) and atrial septal defect with right aortic arch (n=1; 2%). Fifteen (28%) patients had a systemic right ventricle (RV): 13 (24%) with congenitally corrected transposition of great arteries, and 2 (4%) with transposition of the great arteries after Mustard repair.

Compared to baseline, CRT was associated with significant improvement at early follow-up in NYHA functional class, QRS duration, cardiothoracic ratio, left and right atrial volume index (P<0.05 for all) in the overall population; improvement in NYHA class was sustained at late follow-up. Amongst patients with a systemic LV, there was significant increase in LV ejection fraction and reduction in LV end-systolic volume at early and late follow up (P<0.05 for both). There is trend in improvement of RV fractional area change in the patients with a systemic RV but not met statistical significance (P=0.070). Findings were summarized in Figure 1.

Eleven patients died and 2 had heart transplantation unrelated to systemic ventricular morphology. Thirty-five (65%) patients responded positively to CRT but only baseline QRS duration was a predictor of the positive response.

Conclusion

CRT results in sustained improvement in functional class, systemic LV size and function. QRS duration but not QRS morphology was a predictor of the positive response seen at early follow-up in 2/3 of ACHD patients.

Knockdown of long non-coding RNA LUCAT1 reverses high glucose-induced cardiomyocyte injury via targeting CYP11B2

OBJECTIVE

Diabetic cardiomyopathy (DCM) is one of the major complications in patients with diabetes mellitus. Recently, long noncoding RNAs (lncRNAs) have been well concerned for their roles in the progression of multiple diseases, including DCM. In this research, we aimed to explore the role of lncRNA LUCAT1 in cardiomyocyte injury and apoptosis induced by high glucose (HG) in vitro.

MATERIALS AND METHODS

High glucose-induced (HG-induced) AC16 cardiomyocytes transfected with LUCAT1 shRNA were constructed. LUCAT1 expression was detected by real-time quantitative polymerase chain reaction (RT-qPCR). Subsequently, cell proliferation and cell apoptosis were detected after LUCAT1 knockdown in HG-induced AC16 cells. Moreover, RT-qPCR and Western blot assay were performed to explore the potential underlying mechanism of LUCAT1 in DCM.

RESULTS

The expression of LUCAT1 was significantly upregulated in HG-treated AC16 cardiomyocytes. Moreover, knockdown of LUCAT1 could reverse cardiomyocyte injury and apoptosis through downregulating CYP11B2.

CONCLUSIONS

We first demonstrated that knockdown of LUCAT1 could reverse HG-induced cardiomyocyte injury by down-regulating CYP11B2. Our findings might offer a new direction for interpreting the mechanism of DCM development.

P1022Upstream therapy using preoperative renin-angiotensin system inhibitors in prevention of postoperative atrial fibrillation and adverse events: a collaborative pooled-analysis over 27,000 patients

Background

Renin-angiotensin-system inhibitors (RASIs) have been suggested as an upstream therapy for selected AF patients; however, the evidence in surgical setting is limited.

Objective

We aimed to evaluate the role of preoperative RASIs in prevention of postoperative atrial fibrillation (POAF) and adverse events for patients undergoing cardiac surgery.

Methods

In this collaborative pooled-analysis, both randomized and nonrandomized controlled trials comparing preoperative RASIs with no preoperative RASIs treatment on the incidence of POAF were identified. Sensitivity and subgroup analyses of RCTs were performed to test the stability of the overall-effect, and meta-regression to explore the potential risk of bias. The primary outcome was POAF, and the secondary outcomes includes rate of stroke, mortality and duration of hospitalization.

Results

Eleven trials involving 27885 patients (male 74%, median age 65yrs) were included. As compared to the control group, preoperative RASIs did not significantly reduce the risk of POAF (OR: 1.04, 95% CI: 0.91–1.19), stroke (OR: 0.86, 95% CI: 0.62–1.19), death (OR: 1.07, 95% CI: 0.85–1.35), composite adverse cardiac events (OR: 1.04, 95% CI: 0.91–1.18), and hospital stay (WMD: −0.04, 95% CI: −1.05 to 0.98). Pooled-analysis of randomized trials showed consistent results. The primary overall-effect was maintained in sensitivity and subgroup analyses. Meta-regression showed that male-gender was a significant risk-factor of POAF and use of Beta-blockers was associated with a significantly reduced risk in developing POAF.

Conclusion and relevance

This study demonstrates that preoperative RASIs do not offer additional benefit in reducing the risk of postoperative AF, stroke, death and hospitalization in the setting of cardiac surgery. The results provide no support for use of RASIs for the prevention of POAF and adverse events in patients undergoing cardiac surgery.

4965Non-transcriptional disruption of Ca2+i homeostasis and Cx43 function in the right ventricle precedes overt arrhythmogenic cardiomyopathy in PKP2-deficient mice

Background

Plakophilin-2 (PKP2) is classically defined as a protein of the desmosome, an intercellular adhesion structure that also acts as a signaling hub to maintain structural and electrical homeostasis. Mutations in PKP2 associate with most cases of gene-positive arrhythmogenic right ventricular cardiomyopathy (ARVC). A better understanding of PKP2 cardiac biology can help elucidate the mechanisms underlying arrhythmic and cardiomyopathic events that occur consequent to its mutation. Here we sought to captureearly molecular/cellular events that can act as nascent substrates for subsequent arrhythmic/cardiomyopathic phenotypes.

Methods

We used multiple quantitative imaging modalities, as well as biochemical and high-resolution mass spectrometry methods to study the functional/structural properties of cells/tissues derived from cardiomyocyte-specific, tamoxifen-activated, PKP2 knockout mice (“PKP2cKO”). Studies were carried out 14 days post-tamoxifen injection, a time point preceding an overt electrical or structural phenotype.Myocytes from right or left ventricular free wall were studied separately, to detect functional/structural asymmetries.

Results

Most properties of PKP2cKO left ventricular (LV) myocytes were not different from control; in contrast, PKP2cKO right ventricular (RV) myocytes showed increased amplitude and duration of Ca2+transients, increased frequency of spontaneous Ca2+release events, increased [Ca2+] in the cytoplasm and sarcoplasmic reticulum compartments, and dynamic Ca2+accumulation in mitochondria. In addition, RyR2 in RV presented enhanced sensitivity to Ca2+and preferential phosphorylation in a domain known to modulate Ca2+gating. RNAseq at 14 days post-TAM showed no relevant difference in transcript abundance between RV and LV, neither in control nor in PKP2cKO cells, suggesting that in the earliest stage, [Ca2+]i dysfunction is not transcriptional. Rather, we found an RV-predominant increase in membrane permeability that can permit Ca2+entry into the cell. Cx43 ablation mitigated the increase in membrane permeability, the accumulation of cytoplasmic Ca2+and the early stages of RV dysfunction.

Conclusions

Loss of PKP2 creates an RV-predominant arrhythmogenic substrate (Ca2+ dysregulation) that precedes the cardiomyopathy and that is, at least in part, mediated by a Cx43-dependent membrane conduit. Given that asymmetric Ca2+ dysregulation precedes the cardiomyopathic stage, we speculate that abnormal Ca2+ handling in RV myocytes can be a trigger for gross structural changes observed at a later stage.

MicroRNAs in the Intestine: Role in Renewal, Homeostasis, and Inflammation

The mammalian intestine is not only an organ for food digestion and nutrient absorption but also an integral part of the immune and endocrine systems. The intestinal epithelium under stressful environments requires epithelial cells to rapidly elicit changes in gene expression patterns to regulate their survival, adapt to stress, and maintain epithelial homeostasis. Recently, miRNAs have emerged as a novel class of posttranscriptional gene regulators that are fundamentally involved in many aspects of intestinal epithelial differentiation, architecture, and barrier function. In this review, we highlight the critical roles of miRNAs in both the crypt-villus axis of cellular self-renewal and inflammation in the mammalian intestinal mucosa and their impact on the microbiota. We also discuss the functions of specific miRNAs within the intestine to better understand the cellular mechanisms that promote intestinal homeostasis, and the influence of dietary components in the regulation of endogenous miRNA in the study of nutrition and gene regulation in intestinal health.

[Real world study and its application in gastrointestinal stromal tumor]

Gastrointestinal stromal tumor (GIST) is a relatively rare type of gastrointestinal tract tumors. Thus, it is difficult to perform randomized controlled trials (RCTs) of GIST in a single center, which are often plagued by a small number of participants. Real world study (RWS) is a complement to the evidence derived from traditional RCT. Emerging sources of real world data offer enormous opportunity for deeper understanding of why treatments work (or not) and for whom. Evidence generated from RWD can help clarify best use of treatments for individuals and populations, and care value. Thus, RWS of GIST has attracted much attention. RWS helps us better understand the diagnosis, treatment, prognosis and outcome prediction of GIST in clinical practice. GIST is often misdiagnosed as other tumor. A diagnostic test provides evidence on how well a test correctly identifies or rules out GIST. Therapeutic research aims to evaluate the effectiveness and/or safety of a therapy for GIST. Prognostic research aims to forecast the likely outcome of GIST, explore the factors affecting the outcome, and analyze quality of life. Predictive research aims to quantify the probability of identification or health outcome of GIST based on a set of predictors. Pharmacoeconomic data in real world can evaluate the cost-effectiveness of medicinal products for GISTs and serve as a guidance tool for optimal healthcare resource allocation. Attaching importance to data sourse and data quality, strenthening communicate with a qualified statistician, and the implementation of a standardized process are necessary for performing a high-quality RWS.

Quasiparticle states of on-demand coherent electron sources

We introduce a general approach to extract the wave function of quasiparticles from the scattering matrix of a quantum conductor, which offers a unified way to study the features of quasiparticles from on-demand coherent electron sources with different configurations. We first show that the quasiparticles are particle-hole pairs in the Fermi sea, which can be indexed with the flow density [Formula: see text]. Both the excitation probability and the particle/hole components of the quasiparticles can be solely decided from the polar decomposition of the scattering matrix. By using such approach, we then investigate the quasiparticles from the electron sources based on a quantum point contact and a quantum dot (QD). We find that the quasiparticles from different electron sources have different features, which can be seen from the corresponding [Formula: see text]-dependence of the excitation probability and the particle/hole components. We further show that these features can also be characterized by the full counting statistics of the quasiparticles, which can be approximated by a binomial distribution with cumulant generating function [Formula: see text]. For the quantum-point-contact-based electron sources, both [Formula: see text] and [Formula: see text] are monotonically increasing functions of the driving strength. In contrast, for the quantum-dot-based electron sources, both [Formula: see text] and [Formula: see text] can exhibit oscillations, which can be attributed to the interplay between the charge excitation and charge relaxation processes in the QD.

Revision of a CHF correlation for PWR under low pressure conditions with only dimensionless parameters as independent variables

Accurate prediction of the critical heat flux (CHF) is one of the key tasks of PWR core design and safety assessment, for the maximal allowable heat flux in the reactor core is limited by CHF. Since CHF in rod bundle cannot be predicted analytically, up-to-date predictive approach is based on empirical correlations related to the local thermal-hydraulic conditions, geometry and power distribution. However, development of CHF correlation for PWR fuel assemblies under low pressure conditions (2–10 MPa) is constrained by limited amount of experimental data points, which builds up in statistics a typical problem of small sample amounts, but requiring simultaneously high prediction accuracy. In our previous study, stepwise regression method was applied to develop a dimensional, empirical CHF correlation for PWR under low pressure conditions, termed as the advanced low pressure CHF correlation (ALPC), which successfully solves the challenge of small sample problem. However, the ALPC correlation still uses dimensional independent variables with less physical meanings, which limits its physical interpretability. In the current study, stepwise regression method was used to develop a revised, dimensionless version of the ALPC CHF correlation. First, various dimensionless, two-phase thermal-hydraulic parameters that might influence CHF were selected as candidate independent variables. With stepwise regression, the form and coefficients of the revised CHF correlation were optimized in a dynamic manner. Compared to the current ALPC correlation, the revised version developed in this study possesses a similar simple form but a much higher prediction accuracy. Revision of the ALPC correlation demonstrates clearly the advantages of utilizing dimensionless parameters as independent variables in CHF correlation, which points out a new direction of developing rod-bundle CHF correlations for engineering purpose.

Gut microbiota of newborn piglets with intrauterine growth restriction have lower diversity and different taxonomic abundances

Aim

Intrauterine growth retardation (IUGR) is a prevalent problem in mammals. The present study was conducted to unveil the alterations in intestinal microbiota in IUGR piglets.

Methods and Results

We identified the alterations of small intestinal microbiota in IUGR piglets on 7, 21 and 28 days of age using 16S rRNA sequencing. The results showed that IUGR piglets had a decreased alpha diversity of jejunum microbiota at 7 and 21 days of age; had lower abundances of Bacteroidetes and Bacteroides in the jejunum at 7, 21 and 28 days of age, Oscillibacter in the jejunum at 21 days of age, and Firmicutes in the ileum at 21 days of age; whereas they had higher abundances of Proteobacteria and Pasteurella in the ileum at 21 days of age and Escherichia–Shigella in the jejunum at 28 days of age. Correlation analysis showed that Bacteroides, Oscillibacter and Ruminococcaceae_UCG‐002 compositions were positively associated with the body weight (BW) of IUGR piglets, nevertheless Proteobacteria and Escherichia–Shigella relative abundances were negatively correlated with the BW of IUGR piglets. Gene function prediction analysis indicated that microbiota‐associated carbohydrate metabolism, lipid metabolism, glycan biosynthesis and metabolism, amino acid metabolism, and xenobiotics biodegradation and metabolism were downregulated in the IUGR piglets compared to control piglets.

Conclusions

The present study profiled the intestinal microbiota of newborn piglets with IUGR and the newborn IUGR piglets have lower diversity and different taxonomic abundances. Alterations in the abundances of Bacteroidetes, Bacteroides, Proteobacteria Escherichia–Shigella and Pasteurella may be involved in nutrient digestion and absorption, as well as the potential mechanisms connecting to the growth and development of IUGR in mammals.

Significance and Impact of the Study

The small intestinal microbiota were highly shaped in the IUGR piglets, which might further mediate the growth and development of IUGR piglets; and the gut microbiota could serve as a potential target for IUGR treatment.

[Application of radiomics captured from CT to predict the EGFR mutation status and TKIs therapeutic sensitivity of advanced lung adenocarcinoma]

Objective: To explore the ability of computed-tomography (CT) radiomic features to predict the Epidermal growth factor receptor (EGFR) mutation status and the therapeutic response of advanced lung adenocarcinoma to EGFR- Tyrosine kinase inhibitors (TKIs) treatment. Methods: A retrospective analysis was performed on 253 patients diagnosed as advanced lung adenocarcinoma, who underwent EGFR mutation detection, and those with EGFR sensitive mutation were treated with TKIs. Using the Lasso regression model and the 10 fold cross-validation method, the radiomic features of predicted EGFR mutation status and the screening of TKIs for sensitive populations were obtained. 715 radiomic features were extracted from unenhanced, arterial phase and venous phase, respectively. Results: The area under curve (AUC) values of the multi-phases including unenhanced, arterial phase and venous phase of the EGFR mutation status validation group were 0.763, 0.807 and 0.808, respectively. The number of radiomic features extracted from the multi-phases were 5, 18 and 23, respectively, which could distinguish the EGFR mutation status. The AUC values of the multi-phases of the EGFR-TKIs sensitive validation group were 0.730, 0.833 and 0.895, respectively. The number of radiomic features extracted from the multi-phases were 3, 7 and 22, respectively, which can be used to screen the superior population for TKIs treatment. The efficiency of radiomic features extracted from venous phase in predicting EGFR mutant status and EGFR-TKIs sensitivity was significantly superior than those of unenhanced and arterial phase. Conclusions: The radiomic features of CT scanning can be used as the radiomics biomarker to predict the EGFR mutation status of lung adenocarcinoma and to further screen the dominant population in TKIs therapy, which provides the basis for targeted therapy.

[Related factors on skip metastasis of neck lymph node in papillary thyroid carcinoma]

Objective: To investigate the correlation between skip metastasis of neck lymph node and clinicopathological features in papillary thyroid carcinoma. Methods: Totally 272 papillary thyroid carcinoma patients with lateral lymph node metastases who received surgical procedure at Department of Thyroid Surgery, the First Hospital of the Jilin University from January 2014 to June 2016 were analyzed retrospectively. There were 105 male and 167 female patients, aging from 16 to 73 years with a mean age of (42±8) years. There were 29 patients (10.7%) with skip metastasis. And then the correlation between skip metastasis of neck lymph node and clinicopathological features was analyzed by χ(2) test and multivariate Logistic regression test. Results: The rate of skip metastasis in all patients was 10.7% (29/272). By summarizing the distribution of the lateral lymph nodes about the patients with skip metastasis, 16 cases metastasized in single level (55.2%), meanwhile 6 in two levels (20.7%) and 7 in three levels (24.1%). Strong correlation between age, tumor location and skip metastasis was found using χ(2) test (χ(2) values were 14.056 and 21.362 respectively, both P values were 0.000). Age (>45 years) (OR=4.318, 95% CI: 1.767 to 10.552, P=0.001), microcarcinoma (OR=2.623, 95% CI: 1.013 to 6.795, P=0.047)and the tumor located in the upper of the thyroid (OR=11.982, 95% CI: 2.533 to 56.173, P=0.002) were risk factors to the skip metastasis through multivariable Logistic regression analysis. Conclusions: Age >45 years old, microcarcinoma or tumor located in the upper part of the thyroid gland was more likely present with skip metastasis. Skip metastases are often involved in the lateral multi-level. Therefore, confronted patients with one of these risk factors, the occurrence of skip metastasis should be awared when the lateral lymph node was large abnormally. Accordingly, it may be appropriate to extend the indications of fine needle aspiration for lateral lymph node in order to prevent missed diagnosis.

Neural stem cells promote glioblastoma formation in nude mice

PURPOSE

Neural stem cells (NSCs) have been characterized with the ability of self-renewal and neurogenesis, which has inspired lots of studies to clarify the functions of NSCs in neural injury, ischemic stroke, brain inflammation and neurodegenerative diseases. We focused on the relationship of NSCs with glioblastoma, since we have discovered that recurrent glioblastomas were inclined to be derived from subventricular zone (SVZ), where NSCs reside. We want to clarify whether NSCs are involved in glioblastoma relapse.

METHODS

Immunocytochemistry was used to confirm the stemness of NSCs. The Cell Counting Kit-8 was used to measure the proliferation of cells. Migration abilities were examined by wound healing and transwell assays, and tumor formation abilities were confirmed in nude mice.

RESULTS

We found in experiments that NSCs promoted proliferation of a glioblastoma cell line-Ln229, the migration ability of Ln229 cells was motivated by co-cultured with NSCs. Tumor formation of Ln229 cells was also accelerated in nude mice when co-transplanted with NSCs. In immunohistochemistry, we found that the Sox2- and Ki67-positive cells were much higher in co-transplanted groups than that of control groups.

CONCLUSIONS

These results imply the potential role that NSCs play in speeding up tumor formation in the process of glioblastoma relapse, providing the basis for dealing with newly diagnosed glioblastoma patients, which may help postpone the recurrence of glioblastoma as far as possible through preprocessing the tumor-adjacent SVZ tissue.

Abstract P5-07-15: Adipose-derived peptides from breast cancer patients promote the malignancy of breast cancer MCF-7 cells

Adipose stromal/stem cells (ADSCs) could regulate malignancy behaviors of breast cancer, which was due to adipose-derived cytokines in part, such as leptin and resistin. Recently, peptides have been demonstrated to be potential targets for cancer therapy. It's valuable to analyze the characters of adipose-secreted peptides systematically. In this study, we isolated primary adipocytes from adipose tissue adjacent to breast tumor and breast benign lesions respectively, and then co-cultured breast cancer cells MCF-7 with tumor adjacent adipocytes (TAAs)/breast benign adipocytes (BBAs) separately. Compared to BBAs, TAAs could promote proliferation and migration ability of MCF-7. Then we extracted and purified peptides from supernatant of TAAs and BBAs using ultrafiltration, and the effects of TAAs-derived peptides compound on breast cancer cells appeared accordance with the adipose cells. 100 peptides, which were derived from 90 protein precursors, were found to be differentially secreted between TAAs and BBAs by LC-MS/MS (p &lt; 0.05). Gene Ontology (GO) and Pathway analyses appeared that these altered peptides were mainly contributed to cell adhesion, and regulation of Ras-protein signal transduction. These results showed that these differentially secreted peptides could regulate breast cancer cell malignancy, which indicated that they could be potential therapeutic targets and diagnostic bio-marker for breast cancer.

Citation Format: Fu Z, Li W, Wu H, Huang X, Li J, Sun C, Tang J, Yin Y. Adipose-derived peptides from breast cancer patients promote the malignancy of breast cancer MCF-7 cells [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 P5-07-15.

Abstract P3-10-29: tRNA-derived fragments as novel predictive biomarkers for trastuzumab-resistant breast cancer

Background: Resistance to trastuzumab remains a common challenge to HER-2 positive breast cancer. Up until now, the underlying mechanism of trastuzumab resistance is still unclear. tRNA-derived small non-coding RNAs, a new class of small non-coding RNA (sncRNAs), have been observed to play an important role in cancer progression. However, the relationship between tRNA-derived fragments and trastuzumab resistance is still unknown.

Methods:We detected the levels of tRNA-derived fragments expression in normal breast epithelial cell lines, trastuzumab-sensitive and -resistant breast cancer cell linesusing high-throughput sequencing.qRT-PCR was conducted to validate the differentially expressed fragments in serums from trastuzumab-sensitive and -resistant patients. A receiver operating characteristic (ROC) curve analysis was performed to evaluate the power of specific tRNA-derived fragments.Progression-free survival (PFS) was analyzed using Cox-regression.

Results:Our sequence results showed that tRNA-derived fragments were differentially expressed in the HBL-100, SKBR3, and JIMT-1 cell lines. tRF-30-JZOYJE22RR33 and tRF-27-ZDXPHO53KSN were found significantly upregulated in trastuzumab-resistant patients compared to sensitive individuals, and the ROC analysis showed that tRF-30-JZOYJE22RR33 and tRF-27-ZDXPHO53KSN were correlated with trastuzumab resistance. In a multivariate analysis, higher levels of tRF-30-JZOYJE22RR33 and tRF-27-ZDXPHO53KSN expression were associated with significantly shorter PFS in patients with metastatic HER-2 positive breast cancer.

Conclusion: Our results suggest that tRF-30-JZOYJE22RR33 and tRF-27-ZDXPHO53KSN play important roles in trastuzumab resistance. Patients with high levels of tRF-30-JZOYJE22RR33 and tRF-27-ZDXPHO53KSN expression benefitted less from trastuzumab-based therapy than those that express lower-levels of these molecules. tRF-30-JZOYJE22RR33 and tRF-27-ZDXPHO53KSN may be potential biomarkers and intervention targets in the clinical treatment of trastuzumab-resistant breast cancer.

Citation Format: Sun C, Li W, Wu H, Huang X, Li J, Fu Z, Tang J, Yin Y. tRNA-derived fragments as novel predictive biomarkers for trastuzumab-resistant breast cancer [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 P3-10-29.

Abstract P6-17-34: Not presented

This abstract was not presented at the conference.

Citation Format: Yang F, Yin Y, Jiang Z. 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 P6-17-34.

Abstract P2-02-16: Not presented

This abstract was not presented at the conference.

Citation Format: Li Y, Chu J, Li J, Tang J, Yin Y. 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 P2-02-16.

Abstract P4-14-14: Clinicopathological features and endocrine therapy mode of ER low expression (1%-9%) breast cancer patients in China

Purpose: Since 2010, ASCO/CAP recommended that ER be considered positive if ≥1% tumor cells with positive nuclear staining by immunohistochemistry (IHC) in breast cancer. ASCO/CAP also recommended considering endocrine therapy (ET) in ER positive patients. However, most breast cancers are either ER negative or ER strongly positive (≥10%), and tumors with low ER (1-9%) expression are rare. Up to now, the effect of ET is controversial for these patients with ER 1-9% and unfortunately, we know little about the clinical information of this subgroup. In this study, we analyzed the clinicopathological characteristics and ET mode of patients with low ER expression. We sought to figure out whether the ASCO/CAP guidelines affect clinical ET decision in China and Which features are important considerations for doctors to choose ET. We also evaluated the efficacy of ET in these patients. Methods: Patients diagnosed stage I-III primary invasive breast cancer with ER low expression (1-9%) between January 2008 and December 2016 were retrospectively identified from six hospitals in China. Result: 457 patients (2.7%) had low expression of ER (1-9%) of 17216 patients. Mean age at diagnosis was 49 years. 288 patients (49.9%)were younger than 50 years old. 254 patients (55.6%) had stage II disease and 37 patients (8.1%) had lymphovascular invasion (LVI). 260 patients (56.9%) were HER2 positive; 408 patients had PR negative or low expression; 327 patients' (71.6%) Ki-67 status were &gt; 20%. 388 patients (85%) received chemotherapy. Of those 388 patients, 90% patients received anthracycline combined with taxol chemotherapy regimens. 170 patients (37.2%)received ET. Before 2010, only 25.7% patients with low ER expression received ET. The proportion of ET increased after the 2010 ASCO/CAP guideline was published. In 2013, 50% patients received ET. The rate of ET was totally different in six hospitals. 55% patients received ET in the hospital with highest rate, while only 4% patients received ET in the hospital with lowest rate. Using the univariate logistic regression analysis of ET, ER expression, PR expression, Ki-67 status and LVI were associated with the rate of ET. But after adjustment for other covariates, only ER level was significantly associated with the rate of ET. Compared to patients with ER&lt;5% tumors, patients with ER≥5% tumors had a significantly higher probability of ET rate (OR, 2.882; 95% CI: 1.928-4.308; P &lt; 0.001). Median follow time was 30 months. The 5-year RFS rate was 85%. Younger age and positive lymph nodes were associated with worse RFS. Survival rate did not differ significantly between patients with or without ET (without ER vs with ET: OR, 0.870; 95% CI: 0.508-1.448; p=0.61). Conclusions: 2010 ACSO/CAP recommendation indeed result in an increase of ET rate for patients with 1%-9% ER positive. But these patients do not appear to benefit from ET. Prospective studies are needed for these patients and we need more accurate way to evaluate ER levels, which associate with endocrine response.

Citation Format: Fu P, Wang S, Yao M, Xiang A, Li J, Wang H, Geng C, Jin F, Yin Y, Huang X, Jiang Z. Clinicopathological features and endocrine therapy mode of ER low expression (1%-9%) breast cancer patients in China [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 P4-14-14.

High-sensitivity salinity sensor based on optical microfiber coil resonator

A simple, compact, and high-sensitivity optical sensor for salinity measurement is reported based on an optical microfiber coil resonator (MCR). The MCR is manufactured by initially wrapping microfiber on a polymethylmethacrylate (PMMA) rod, which is dissolved to leave a hollow cylindrical fluidic channel within the coil for measurement. Based on the light propagation through the MCR, the device's spectrum moves to long wavelengths with increased salinity in the fluid. The MCR device's sensitivity can reach up to 15.587 nm/% with a resolution of 1.28 × 10^-3%. It is also confirmed that the temperature dependence is 79.87 pm/°C, which results from the strong thermal-expansion coefficient of the low refractive index epoxy. The experimental results indicate that the device can be widely used as a high sensitivity salinity sensor in water and other liquids due to its stability, compactness, electromagnetic immunity, and high sensitivity.

Birth population survey in Huai'an in 2015: perinatal-neonatal mortality and preterm birth rate in emerging regions in China

Objective: This survey followed the birth population-based study conducted in 2010 in Huai'an, Jiangsu Province, with the aim to estimate perinatal-neonatal mortality and preterm birth rate in emerging regions with similar maternal-fetal and neonatal care conditions in China.Materials and methods: Data of total births in 2015 were prospectively collected by regional perinatal network collaboration in Huai'an, a subprovincial region with a population of 5,644,500 and gross domestic production of 9082 USD per capita.Results: The 59,424 birth registries (including 59,023 live births and 167 stillbirths) corresponded to a birth rate of 10.5‰ and a Male-to-female ratio of 113.7:100. All births there were from 85, 16, and 6 level I, II, and III hospitals, with a delivery rate of 30.4, 40.2, and 29.4%, respectively. Of all births, 14.1% had pregnancy-associated comorbidities and complications, 54.4% (32,226/59,190) had cesarean delivery, and multiple pregnancies and birth defects occurred in 2.1% (1,250) and 5.5‰ (324), respectively. The mean birth weight was 3448 ± 507 g with 13.9% being macrosomia, and 2.86% (1695/59,190) low birth weight. Preterm birth rate was 4.06% (2404/59,190) with a mortality rate of 8.5%. There were 94.5% recorded as healthy newborns and 5.5% (3263) requiring hospitalization after birth. The perinatal and neonatal mortality rate was 5.2‰ (167 stillbirths, 139 early neonatal deaths) and 4.0‰, respectively. Compared with the 2010 survey, these data demonstrated generally improved status of perinatal-neonatal healthcare.Conclusions: The low rates of perinatal-neonatal mortality, preterm birth and preterm mortality suggest that the concept and study protocol of perinatal-neonatal healthcare in Huai'an may serve as the benchmark for estimating regional vital statistics and perinatal and neonatal outcomes.

[Analysis of acute occupational poisoning events in China during 2006-2016]

Objective: To analyze the epidemic characteristics of acute occupational poisoning events in order to state the regularity of outbreak and provide scientific evidences of prevention and control measure in China. Methods: According to the report information from the Management Information System of Public Health Emergency, we analyzed acute occupational poisoning events time distribution, regional distribution, toxicant variety, route of exposure and events detection from 2006 to 2016. Results: The total number of acute occupational poisoning events reported in 26 provinces of China from 2006 to 2016 was 337, causing 2 399 people poisoned, and the fatality rate was 18.09%. Majority of them were higher grade events and the top three provinces of acute occupational poisoning events were Shanghai, Anhui, Shandong. Inhalation is the main cause of poisoning. The acute occupational poisoning events for carrying out poison dectection were accounted for 56.68%. Conclusion: Acute occupational poisoning events in China is reducing year by year, But fatality rate is not decrease. So the country should increase the supervision and management of safety in production, strengthen the safety education of employees and coordination mechanism among different departments.