Risk assessment for precise intervention of COVID-19 epidemic based on available big data and spatio-temporal simulation method: Empirical evidence from different public places in Guangzhou, China.

Risk assessment of the intra-city spatio-temporal spreading of COVID-19 is important for providing location-based precise intervention measures, especially when the epidemic occurred in the densely populated and high mobile public places. The individual-based simulation has been proven to be an effective method for the risk assessment. However, the acquisition of individual-level mobility data is limited. This study used publicly available datasets to approximate dynamic intra-city travel flows by a spatio-temporal gravity model. On this basis, an individual-based epidemic model integrating agent-based model with the susceptible-exposed-infectious-removed (SEIR) model was proposed and the intra-city spatio-temporal spreading process of COVID-19 in eleven public places in Guangzhou China were explored. The results indicated that the accuracy of dynamic intra-city travel flows estimated by available big data and gravity model is acceptable. The spatio-temporal simulation method well presented the process of COVID-19 epidemic. Four kinds of spatial-temporal transmission patterns were identified and the pattern was highly dependent on the urban spatial structure and location. It indicated that location-based precise intervention measures should be implemented according to different regions. The approach of this research can be used by policy-makers to make rapid and accurate risk assessments and to implement intervention measures ahead of epidemic outbreaks.

Quantitative Evaluation of Myocardial Strain After Myocardial Infarction with Cardiovascular Magnetic Resonance Tissue-Tracking Imaging.

To investigate the value of cardiovascular magnetic resonance tissue-tracking (CMR-TT) imaging in the differentiation of subendocardial and transmural myocardial infarction (MI) and determine whether strain parameters are enable to detect adverse left ventricular (LV) remodeling.Global peak circumferential, longitudinal, and radial strains (GPCS, GPLS, GPRS) and segmental peak circumferential, longitudinal, and radial strains (PCS, PLS, PRS) in accordance with the 16-segment model were all derived. All positive segments were divided into two groups according to transmural degree. All patients were dichotomized in accordance with the existence of LV remodeling, which was defined as infarct size (IS) > 24%.Patients with MI showed significant lower GPRS, GPCS, and GPLS than the control group (16.41% ± 8.92%, -8.77%± 3.51%, -7.54% ± 2.43% versus 32.41% ± 12.99%, -14.92% ± 3.32%, -11.50% ± 2.51%). Lower PRS [3.25% (-5.57, 7.835) versus 19.94% (12.50, 30.75), P < 0.001] and PCS (-3.81 ± 4.60% versus -8.97± 4.43%, P < 0.001) can be found in transmural infarcted segments compared to subendocardial infarcted segments. PLS between transmural and subendocardial infarcted segments (-4.03% ± 4.88% versus -4.34% ± 4.98%), without however statistical significance (P = 0.523). The optimal cutoff value for PRS in the discriminate diagnosis of MI was 8.97% with a sensitivity of 81.8% and specificity of 98.0%. The optimal cutoff value for PCS was -7.56% with a sensitivity of 83.6% and specificity of 72.1%. Receiver operating characteristic (ROC) analysis revealed an optimal cutoff GPRS of 15.45%, and GPCS of -6.72% yielded high diagnostic accuracy in the identification of remodeling, which was higher than left ventricular ejection fraction (LVEF).CMR-TT can differentiate between subendocardial and transmural infarction and detect LV remodeling, and the diagnostic value was superior to conventional functional parameters.

Identification of heart failure with preserved ejection fraction in patients with hypertension: a left atrial myocardial strain cardiac magnetic resonance study.

Background: The noninvasive diagnosis of heart failure with preserved ejection fraction (HFpEF) remains challenging. The role of left atrial (LA) functional changes in patients with HFpEF has attracted increased attention. This study aimed to evaluate LA deformation in patients with hypertension (HTN) using cardiac magnetic resonance tissue tracking and to investigate the diagnostic value of LA strain for HFpEF. Methods: This retrospective study consecutively enrolled 24 HTN patients with HFpEF (HTN-HFpEF) and 30 patients with pure HTN based on clinical indications. Thirty age-matched healthy participants were also enrolled. All participants underwent a laboratory examination and 3.0 T cardiovascular magnetic resonance (CMR). The LA strain and strain rate, including total strain (εs), passive strain (εe), active strain (εa), peak positive strain rate (SRs), peak early negative strain rate (SRe), and peak late negative strain rate (SRa), were evaluated using CMR tissue tracking and compared among the 3 groups. Receiver operating characteristic (ROC) analysis was used to identify HFpEF. Spearman correlation was used to analyze the correlation between LA strain and brain natriuretic peptide (BNP) level. Results: Patients with HTN-HFpEF had significantly lower εs (17.70%, IQR 14.65% to 19.70%, εe 7.83%±2.86%), εa (9.08%±3.19%), SRs (0.88±0.24 s-1), SRe (-0.60 s-1, IQR -0.90 to -0.50 s-1), and SRa (-1.10±0.47 s-1) than did patients with HTN and control participants (all P values <0.05). Compared to the control group, patients with HTN had lower εs (25.35%, IQR 21.80% to 27.25%), εe (11.49%±2.64%), SRs (1.10 s-1, IQR 1.00 to 1.48 s-1), and SRe (-1.11±0.37 s-1) (all P values <0.05). The values of εa and SRa were not significantly different between the HTN and control groups. LA total strain εs was independently associated with HFpEF (odds ratio 0.009; P<0.05) with a cutoff value of 19.55% (95% CI: 0.882-0.996), and the sensitivity and specificity were 75% and 97%, respectively. There was a good correlation between the LA strain parameters and BNP level (all P values <0.05). Conclusions: LA function impairment exists in patients with HFpEF. The LA strain parameter has potential value in diagnosing HFpEF.

SnO2 Anchored in S and N Co-Doped Carbon as the Anode for Long-Life Lithium-Ion Batteries.

Tin dioxide (SnO2) has been the focus of attention in recent years owing to its high theoretical capacity (1494 mAh g-1). However, the application of SnO2 has been greatly restricted because of the huge volume change during charge/discharge process and poor electrical conductivity. In this paper, a composite material composed of SnO2 and S, N co-doped carbon (SnO2@SNC) was prepared by a simple solid-state reaction. The as-prepared SnO2@SNC composite structures show enhanced lithium storage capacity as compared to pristine SnO2. Even after cycling for 1000 times, the as-synthesized SnO2@SNC can still deliver a discharge capacity of 600 mAh g-1 (current density: 2 A g-1). The improved electrochemical performance could be attributed to the enhanced electric conductivity of the electrode. The introduction of carbon could effectively improve the reversibility of the reaction, which will suppress the capacity fading resulting from the conversion process.

Optimizing Spatial Allocation of COVID-19 Vaccine by Agent-Based Spatiotemporal Simulations.

Optimizing allocation of vaccine, a highly scarce resource, is an urgent and critical issue during fighting against on-going COVID-19 epidemic. Prior studies suggested that vaccine should be prioritized by age and risk groups, but few of them have considered the spatial prioritization strategy. This study aims to examine the spatial heterogeneity of COVID-19 transmission in the city naturally, and optimize vaccine distribution strategies considering spatial prioritization. We proposed an integrated spatial model of agent-based model and SEIR (susceptible-exposed-infected-recovered). It simulated spatiotemporal process of COVID-19 transmission in a realistic urban context. Individual movements were represented by trajectories of 8,146 randomly sampled mobile phone users on December 28, 2016 in Guangzhou, China, 90% of whom aged 18-60. Simulations were conducted under seven scenarios. Scenarios 1 and 2 examined natural spreading process of COVID-19 and its final state of herd immunity. Scenarios 3-6 applied four vaccination strategies (random strategy, age strategy, space strategy, and space & age strategy), and identified the optimal vaccine strategy. Scenario 7 assessed the most appropriate vaccine coverage. The results demonstrates herd immunity is heterogeneously distributed in space, thus, vaccine intervention strategies should be spatialized. Among four strategies, space & age strategy is substantially most efficient, with 7.7% fewer in attack rate and 44 days longer than random strategy under 20% vaccine uptake. Space & age strategy requires 30%-40% vaccine coverage to control the epidemic, while the coverage for a random strategy is 60%-70% as a comparison. The application of our research would greatly improves the effectiveness of the vaccine usability.

Serum amyloid A activates peroxisome proliferator-activated receptor γ through extracellularly regulated kinase 1/2 and COX-2 expression in hepatocytes.

Serum amyloid A (SAA) is an acute phase protein whose level of expression increases markedly during bacterial infection, tissue damage, and inflammation. The potential beneficial roles of SAA include its involvement in reverse cholesterol transport and possibly extracellular lipid deposition at sites of inflammation and tissue repair. It is an attractive therapeutic target for the treatment of atherosclerosis. Peroxisome proliferator-activated receptor γ (PPARγ) plays a major regulatory role in adipogenesis and in the expression of genes involved in lipid metabolism. Activation of PPARγ leads to multiple changes in gene expression, some of which are believed to be atherogenic while others are antiatherogenic. In this study, we investigated the effects of SAA on PPARγ activation and its downstream target gene expression profiles in HepG2 cells. We demonstrated that SAA could activate PPARγ transcriptional activity. Preincubation of HepG2 cells with SAA enhanced the efflux of cholesterol to HDL and apoA-I. In addition, SAA increased the level of intracellular 15-deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2), which is a potent natural ligand for PPARγ. Our data suggested that SAA activated PPARγ through extracellular signal-regulated kinase 1/2 (ERK1/2)-dependent COX-2 expression. Furthermore, SAA-induced cholesterol efflux was suppressed when the ERK1/2 pathway or COX-2 was inhibited. Overall, our study has established, for the first time, a relationship between SAA and PPARγ. Additionally, the data from our study have also provided new insights into the role of SAA in cholesterol efflux.

Association between serum amyloid A and obesity: a meta-analysis and systematic review.

BACKGROUND: Emerging evidence indicates an association of the acute-phase protein serum amyloid A (SAA) with obesity. Here we review and summarize quantitatively the available data related to this association. METHODS: PubMed was systematically searched using the terms "serum amyloid A" and "obesity." Eighty-one relevant studies between January 1966 and July 2009 were identified. Of these, only 11 cross-sectional studies and 10 prospective studies with successful interventions met our inclusion criteria for the meta-analysis. All analyses were conducted using the Comprehensive Meta-Analysis software. Literature pertaining to the relationship between SAA and other inflammatory markers, and the association between SAA and obesity-related disorders, such as cardiovascular diseases, atherosclerosis, diabetes, and insulin resistance was also reviewed. RESULTS: A strong association between body mass index and SAA levels was found in the 11 cross-sectional studies. The overall correlation coefficient is 0.230 (95% CI 0.160-0.297, P < 0.0005). The ten prospective studies were subsequently analyzed, and the difference in SAA levels before and after weight loss, expressed as standardized mean difference was -0.480 (95% CI -0.678 to -0.283, P < 0.0005). We discuss some potential underlying mechanisms and clinical applications for reducing SAA levels in obesity.

Impact of multicenter unified enhanced environmental cleaning and disinfection measures on nosocomial infections among patients in intensive care units.

OBJECTIVES: Most Chinese hospitals have customized environmental cleaning policies and systems, with limited data availability based on evidence-based medicine. This study investigated the relationship between multidrug-resistant organism (MDRO) colonization in intensive care unit (ICU) patients and ICU surface bacterial contamination status. METHODS: This cross-sectional study comprised MDRO screening in ICU patients using bacterial cultivation by chromogenic medium; samples were collected before (control group) and after implementation of enhanced cleaning (cleaning group). Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used to identify and analyze microorganisms; the relationships of MDRO colonization with infection and environmental bacteria were analyzed. RESULTS: In total, 196 patients were enrolled in the study (104 and 92 in control and cleaning groups, respectively); 1042 MDROs were subjected to screening before and after cleaning. After cleaning, the rate of MDRO detection on surfaces of frequently touched objects in ICUs decreased from 31.77% to 13.32%. There were fewer MDRO homologues in the cleaning group than in the control group. Moreover, the cleaning group had a shorter ICU stay and significantly lower mortality rate. CONCLUSIONS: Enhanced environmental cleaning and disinfection could reduce environmental MDRO accumulation and suppress MDRO colonization in ICUs, thereby reducing nosocomial infections and improving adverse patient outcomes.

Effects of Carbon Content and Current Density on the Li+ Storage Performance for MnO@C Nanocomposite Derived from Mn-Based Complexes.

In this study, a simple method was adopted for the synthesis of MnO@C nanocomposites by combining in-situ reduction and carbonization of the Mn3O4 precursor. The carbon content, which was controlled by altering the annealing time in the C2H2/Ar atmosphere, was proved to have great influences on the electrochemical performances of the samples. The relationships between the carbon contents and electrochemical performances of the samples were systematically investigated using the cyclic voltammetry (CV) as well as the electrochemical impedance spectroscopy (EIS) method. The results clearly indicated that the carbon content could influence the electrochemical performances of the samples by altering the Li+ diffusion rate, electrical conductivity, polarization, and the electrochemical mechanism. When being used as the anode materials in lithium-ion batteries, the capacity retention rate of the resulting MnO@C after 300 cycles could reach 94% (593 mAh g-1, the specific energy of 182 mWh g-1) under a current density of 1.0 A g-1 (1.32 C charge/discharge rate). Meanwhile, this method could be easily scaled up, making the rational design and large-scale application of MnO@C possible.

Celecoxib inhibits serum amyloid a-induced matrix metalloproteinase-10 expression in human endothelial cells.

BACKGROUND: Although serum amyloid A (SAA) is an established biomarker of coronary artery disease (CAD), its direct role in matrix degradation is obscure. This study investigated the effect of SAA on the expression of matrix metalloproteinase-10 (MMP-10) in endothelial cells. The effect of celecoxib on SAA-dependent MMP-10 expression and its possible mediator were also investigated. METHODS AND RESULTS: From our time course microarray screening, SAA (20 microg/ml) was found to increase MMP-10 mRNA expression over time (4-48 h) in human endothelial cells. Quantitative real-time PCR confirmed this transcriptional induction. Correspondingly, secreted MMP-10 protein was also markedly induced by SAA treatment for 24 h in a dose-dependent manner. We further examined cyclooxygenase-2 (COX-2) and its major product, prostaglandin E(2) (PGE(2)), as possible mediators of MMP-10 induction. Direct PGE(2) treatment could result in MMP-10 induction. Celecoxib, a selective COX-2 inhibitor, suppressed MMP-10 secretion induced by SAA. CONCLUSIONS: SAA induced MMP-10 expression and celecoxib prevented its induction. MMP-10 induction was at least partly mediated by PGE(2).

Examining the Effect of the Environment and Commuting Flow from/to Epidemic Areas on the Spread of Dengue Fever.

Environment and human mobility have been considered as two important factors that drive the outbreak and transmission of dengue fever (DF). Most studies focus on the local environment while neglecting environment of the places, especially epidemic areas that people came from or traveled to. Commuting is a major form of interactions between places. Therefore, this research generates commuting flows from mobile phone tracked data. Geographically weighted Poisson regression (GWPR) and analysis of variance (ANOVA) are used to examine the effect of commuting flows, especially those from/to epidemic areas, on DF in 2014 at the Jiedao level in Guangzhou. The results suggest that (1) commuting flows from/to epidemic areas affect the transmission of DF; (2) such effects vary in space; and (3) the spatial variation of the effects can be explained by the environment of the epidemic areas that commuters commuted from/to. These findings have important policy implications for making effective intervention strategies, especially when resources are limited.

Impact of serum amyloid A on tissue factor and tissue factor pathway inhibitor expression and activity in endothelial cells.

OBJECTIVE: Although serum amyloid A (SAA) is a useful biomarker of coronary artery disease (CAD), its direct role in procoagulation is obscure. This study investigates the impact of SAA on the expression and activity of tissue factor (TF) and tissue factor pathway inhibitor (TFPI) in endothelial cells. METHODS AND RESULTS: SAA was found to disturb the balance of TF and TFPI expression and activity in human endothelial cells. SAA (20 microg/mL) markedly induced TF expression between 4 to 8 hours in both protein and mRNA levels, as well as TF activity. Conversely, incubation of SAA (20 microg/mL) for 24 and 48 hours was found to significantly inhibit TFPI secretion, transcription, and activity. Pretreatment with formyl peptide receptor-like 1 (FPRL1) inhibitors (Pertussis toxin and WRWWWW) could block the SAA effects on TF and TFPI. Furthermore, pretreatment with the respective specific mitogen-activated protein kinase (MAPK) inhibitors (SB203580, PD98059, and SP600125) and NFkappaB inhibitor (Bay-11 to 7082) could block SAA-dependent TF induction. SAA also directly induced activation of MAP kinases and NFkappaB. CONCLUSIONS: The stimulating effect of SAA was faster-acting on the expression and activity of TF and the inhibitory effect was slower-acting on TFPI. The effects are mediated through FPRL1, MAP kinases and NFkappaB.

Effects of atherogenic diet and atorvastatin treatment on gene expression profiles in the C57BL/6J mouse liver.

This study investigated the early and long-term effects of atherogenic diet on hepatic gene expression, and the restorative effects of atorvastatin in treating hypercholesterolemia. Two groups of female C57BL/6J mice were fed standard chow or atherogenic diet for 1-week early phase study and two other groups for 10 weeks. The fifth group had daily 10 mg/kg atorvastatin injections for 3 weeks from week 8 of the atherogenic diet. Gene expression profiling was carried out with Affymetrix GeneChips. One-week atherogenic diet elevated 38 and inhibited 127 gene expressions, while 10-week atherogenic diet elevated 165 and inhibited 281 genes by more than twofold. Atorvastatin could restore 78.2% and 68%, respectively, of the genes to normal levels. Genes in the Insig (insulin-induced gene)-SREBP (sterol regulatory element binding proteins) pathway were mostly inhibited by atherogenic diet at week 1 but elevated at week 10. Of these, 65.2% were restored by atorvastatin. In conclusion, lipid homeostatic mechanism coped well with short-term atherogenic diet. However, when such a diet was prolonged, the mechanism was no longer effective but entered into a pathological state in which lipogenic genes, especially those in the Insig-SREBP pathway, were upregulated. Atorvastatin could restore changes in the Insig-SREBP pathway that were induced by the atherogenic diet.

Comprehensive analysis of gene expression profiles associated with proliferative diabetic retinopathy.

Proliferative diabetic retinopathy (PDR) is characterized by neovascularization on the surface of the retina or the optic disc, which is associated with environmental and genetic factors. However, its regulatory mechanism remains to be fully elucidated, particularly at a multiomics level. In the present study, a comprehensive analysis was performed of the gene expression profile of fibrovascular membranes (FVMs) associated with PDR, including an analysis of differentially expressed genes, functional enrichment, and regulation of transcription factors (TFs). As a result, novel marker genes of PDR were identified, including flavin containing monooxygenase 2. Furthermore, several common or specific genes, pathways and TFs have been recovered for active and inactive FVMs. In the present study, lymphoid enhancer binding factor 1 (LEF1) was identified as an upregulator in active and inactive FVMs, which is capable of activating or repressing target genes, including claudin 2, secreted phosphoprotein 1 (SPP1), and aristaless-like homeobox 4. It was demonstrated that the Wnt/ß-catenin effector LEF1 regulating SPP1 is potentially important in PDR. The results of the present study may provide novel insights into the molecular mechanisms underlying the pathophysiology of PDR.

Inclusion complexes of cypermethrin and permethrin with monochlorotriazinyl-beta-cyclodextrin: a combined spectroscopy, TG/DSC and DFT study.

The suitable size hydrophobic cavity and monochlorotriazinyl group as a reactive anchor make MCT-ß-CD to be widely used in fabric finishing. In this paper, the inclusion complexes of monochlorotriazinyl-beta-cyclodextrin (MCT-ß-CD) with cypermethrin (CYPERM) and permethrin (PERM) are synthesized and analyzed by TG/DSC, FT-IR and Raman spectroscopy. TG/DSC reveals that the decomposed temperatures of inclusion complexes are lower by 25-30 °C than that of physical mixtures. DFT calculations in conjunction with FT-IR and Raman spectral analyses are used to study the structures of MCT-ß-CD and their inclusion complexes. Four isomers of trisubstituted MCT-ß-CD are designed and DFT calculations reveal that 1,3,5-trisubstituted MCT-ß-CD has the lowest energy and can be considered as main component of MCT-ß-CD. The ground-state geometries, vibrational wavenumbers, IR and Raman intensities of MCT-ß-CD and their inclusion complexes were calculated at B3LYP/6-31G (d) level of theory. Upon examining the optimized geometry of inclusion complex, we find that the CYPERM and PERM are inserted into the toroid of MCT-ß-CD from the larger opening. The band at 1646 cm(-1) in IR and at 1668 cm(-1) in Raman spectrum reveals that monochloroazinyl group of MCT-ß-CD exists in ketone form but not in anion form. The noticeable IR and Raman shift of phenyl reveals that these two benzene rings of CYPERM and PERM stays inside the cavity of MCT-ß-CD and has weak interaction with MCT-ß-CD. This spectroscopy conclusion is consistent with theoretical predicted structure.

DFT studies of structure and vibrational spectra of 4-benzylidene-1-phenyl-2-selenomorpholino-1H-imidazol-5(4H)-one and its derivatives.

The Raman spectra and FT-IR spectra of 4-benzylidene-1-phenyl-2-selenomorpholino-1H-imidazol-5(4H)-one and its derivatives have been measured and their ground-state geometries and vibrational spectra are studied by DFT at B3LYP/6-31G(d) level. Comparing the optimized geometries of compounds 1-6, we find that different substituent and substitution site on benzene rings result in very small changes on the imidazoline skeleton, the changes on bond length are within 0.005 Å and on bond angle are within 0.5°. Calculated spectra are well consistent with the experimental one and the deviations are smaller than 30 cm-1. The influence of substituent on IR and Raman spectrum must not be neglected. Electron-withdrawing chlorine atom makes the stretching vibration of carbonyl group shift 4-16 cm(-1) towards higher wavenumber, but electron-donating methoxyl group and dioxole group make it shift 6-10 cm(-1) in IR and 9-13 cm(-1) in Raman spectrum towards lower wavenumber, respectively. Dioxole substitution makes the C=C stretching vibration of phenyl shift to a higher position at 1617-1618 cm(-1). The influence of intermolecular weak interaction on vibrational spectrum is studied by two models (dimer and monomer inclusion van del Waals correction). Dimer model presents a better accuracy, but van del Waals correction on B3LYP hybrid function does not produce a significant change on accuracy in this system.

Prognostic role of C-reactive protein in breast cancer: a systematic review and meta-analysis.

BACKGROUND: Recent studies have shown that C-reactive protein (CRP) may be associated with breast cancer. The purpose of this study is to summarize the predictive role of CRP for survival in breast cancer as shown in all available studies worldwide. METHODS: Related studies were identified and evaluated for quality through multiple search strategies. Data were collected from studies comparing overall, cancer-specific, and disease-free survival (OS, CSS, and DFS) in patients with elevated CRP levels and those having lower levels. Studies were pooled, and combined hazard ratios (HRs) of CRP for survival were calculated. RESULTS: A total of 10 studies (n=4,502) were included for this meta-analysis (9 for OS, 3 for CSS, and 3 for DFS). For overall and disease-free survival, the pooled HRs of CRP were significant at 1.62 (95% confidence interval [95% CI], 1.20-2.18) and 1.81 (95% CI, 1.44-2.26), respectively. For cancer-specific survival, the pooled HR in higher CRP expression in breast cancer was 2.08 (95% CI, 1.48-2.94), which could strongly predict poorer survival in breast cancer. CONCLUSIONS: CRP has a critical prognostic value in patients with breast cancer as an inflammation biomarker.