Impact of High Lipoprotein(a) on Long-Term Survival Following Coronary Artery Bypass Grafting

BACKGROUND

Lipoprotein(a) is a possible causal risk factor for atherosclerosis and related complications. The distribution and prognostic implication of lipoprotein(a) in patients undergoing coronary artery bypass grafting remain unknown. This study aimed to assess the impact of high lipoprotein(a) on the long-term prognosis of patients undergoing coronary artery bypass grafting.

METHODS AND RESULTS

Consecutive patients with stable coronary artery disease who underwent isolated coronary artery bypass grafting from January 2013 to December 2018 from a single-center cohort were included. The primary outcome was all-cause death. The secondary outcome was a composite of major adverse cardiovascular and cerebrovascular events. Of the 18 544 patients, 4072 (22.0%) were identified as the high-lipoprotein(a) group (≥50 mg/dL). During a median follow-up of 3.2 years, primary outcomes occurred in 587 patients. High lipoprotein(a) was associated with increased risk of all-cause death (high lipoprotein(a) versus low lipoprotein(a): adjusted hazard ratio [aHR], 1.31 [95% CI, 1.09-1.59]; P=0.005; lipoprotein(a) per 1-mg/dL increase: aHR, 1.003 [95% CI, 1.001-1.006]; P=0.011) and major adverse cardiovascular and cerebrovascular events (high lipoprotein(a) versus low lipoprotein(a): aHR, 1.18 [95% CI, 1.06-1.33]; P=0.004; lipoprotein(a) per 1-mg/dL increase: aHR, 1.002 [95% CI, 1.001-1.004]; P=0.002). The lipoprotein(a)-related risk was greater in patients with European System for Cardiac Operative Risk Evaluation <3, and tended to attenuate in patients receiving arterial grafts.

CONCLUSIONS

More than 1 in 5 patients with stable coronary artery disease who underwent coronary artery bypass grafting were exposed to high lipoprotein(a), which is associated with higher risks of death and major adverse cardiovascular and cerebrovascular events. The adverse effects of lipoprotein(a) were more pronounced in patients with clinically low-risk profiles or not receiving arterial grafts.

Administrative Model for Profiling Hospital Performance on Coronary Artery Bypass Graft Surgery: Based on the Chinese Hospital Quality Monitoring System

BACKGROUND

We aimed to develop an administrative model to profile the performance on the outcomes of coronary artery bypass grafting across hospitals in China.

METHODS AND RESULTS

This retrospective study was based on the Chinese Hospital Quality Monitoring System (HQMS) from 2016 to 2020. The coronary artery bypass grafting cases were identified by procedure code, and those of 2016 to 2017 were randomly divided into modeling and validation cohorts, while those in other years were used to ensure the model stability across years. The outcome was discharge status as "death or withdrawal," and that withdrawal referred to discharge without medical advice when patients were in the terminal stage but reluctant to die in the hospital. Candidate covariates were mainly identified by diagnoses or procedures codes. Patient-level logistic models and hospital-level hierarchical models were established. A total of 203 010 coronary artery bypass grafts in 699 hospitals were included, with 60 704 and 20 233 cases in the modeling and validation cohorts and 40 423, 42 698, and 38 952 in the years 2018, 2019, and 2020, respectively. The death or withdrawal rate was 3.4%. The areas under the curve were 0.746 and 0.729 in the patient-level models of modeling and validation cohorts, respectively, with good calibration and stability across years. Hospital-specific risk-standardized death or withdrawal rates were 2.61% (interquartile range, 1.87%-3.99%) and 2.63% (interquartile range, 1.97%-3.44%) in the modeling and validation cohorts, which were highly correlated (correlation coefficient, 0.96; P<0.001). Between-hospital variations were distinguished among hospitals of different volumes and across years.

CONCLUSIONS

The administrative model based on Hospital Quality Monitoring System could profile hospital performance on coronary artery bypass grafting in China.

Light induces an increasing release of benzyl nitrile against diurnal herbivore Ectropis grisescens Warren attack in tea (Camellia sinensis) plants

Herbivore-induced plant volatiles (HIPVs) are critical compounds that directly or indirectly regulate the tritrophic interactions among herbivores, natural enemies and plants. The synthesis and release of HIPVs are regulated by many biotic and abiotic factors. However, the mechanism by which multiple factors synergistically affect HIPVs release remains unclear. Tea plant (Camellia sinensis) is the object of this study because of its rich and varied volatile metabolites. In this study, benzyl nitrile was released from herbivore-attacked tea plants more in the daytime than at night, which was consistent with the feeding behaviour of tea geometrid (Ectropis grisescens Warren) larvae. The Y-tube olfactometer assay and insect resistance analysis revealed that benzyl nitrile can repel tea geometrid larvae and inhibit their growth. On the basis of enzyme activities in transiently transformed Nicotiana benthamiana plants, CsCYP79 was identified as a crucial regulator in the benzyl nitrile biosynthetic pathway. Light signalling-related transcription factor CsPIF1-like and the jasmonic acid (JA) signalling-related transcription factor CsMYC2 serve as the activator of CsCYP79 under light and damage conditions. Our study revealed that light (abiotic factor) and herbivore-induced damage (biotic stress) synergistically regulate the synthesis and release of benzyl nitrile to protect plants from diurnal herbivorous tea geometrid larvae.

Regulation of chlorophyll biosynthesis by light-dependent acetylation of NADPH:protochlorophyll oxidoreductase A in Arabidopsis

Chlorophylls are the major pigments that harvest light energy during photosynthesis in plants. Although reactions in chlorophyll biogenesis have been largely known, little attention has been paid to the post-translational regulation mechanism of this process. In this study, we found that four lysine sites (K128/340/350/390) of NADPH:protochlorophyllide oxidoreductase A (PORA), which catalyzes the only light-triggered step in chlorophyll biosynthesis, were acetylated after dark-grown seedlings transferred to light via acetylomics analysis. Etiolated seedlings with K390 mutation of PORA had a lower greening rate and decreased PORA acetylation after illumination. Importantly, K390 of PORA was found extremely conserved in plants and cyanobacteria via bioinformatics analysis. We further demonstrated that the acetylation level of PORA was increased by exposing the dark-grown seedlings to the histone deacetylase (HDAC) inhibitor TSA. Thus, the HDACs probably regulate the acetylation of PORA, thereby controlling this non-histone substrate to catalyze the reduction of Pchlide to produce chlorophyllide, which provides a novel regulatory mechanism by which the plant actively tunes chlorophyll biosynthesis during the conversion from skotomorphogenesis to photomorphogenesis.

Outcome differences between surgeons performing first and subsequent coronary artery bypass grafting procedures in a day: a retrospective comparative cohort study

BACKGROUND

With increasing surgical workload, it is common for cardiac surgeons to perform coronary artery bypass grafting (CABG) after other procedures in a workday. To investigate whether prior procedures performed by the surgeon impact the outcomes, we compared the outcomes between CABGs performed first versus those performed after prior procedures, separately for on-pump and off-pump CABGs as they differed in technical complexity.

METHODS

We conducted a retrospective cohort study of patients undergoing isolated CABG in China from January 2013 to December 2018. Patients were categorised as undergoing on-pump and off-pump CABGs. Outcomes of the procedures performed first in primary surgeons' daily schedule (first procedure) were compared with subsequent ones (non-first procedure). The primary outcome was an adverse events composite (AEC) defined as the number of adverse events, including in-hospital mortality, myocardial infarction, stroke, acute kidney injury and reoperation. Secondary outcomes were the individual components of the primary outcome, presented as binary variables. Mixed-effects models were used, adjusting for patient and surgeon-level characteristics and year of surgery.

RESULTS

Among 21 866 patients, 10 109 (16.1% as non-first) underwent on-pump and 11 757 (29.6% as non-first) off-pump CABG. In the on-pump cohort, there was no significant association between procedure order and the outcomes (all p>0.05). In the off-pump cohort, non-first procedures were associated with an increased number of AEC (adjusted rate ratio 1.29, 95% CI 1.13 to 1.47, p<0.001), myocardial infarction (adjusted OR (OR_adj) 1.43, 95% CI 1.13 to 1.81, p=0.003) and stroke (OR_adj 1.73, 95% CI 1.18 to 2.53, p=0.005) compared with first procedures. These increases were only found to be statistically significant when the procedure was performed by surgeons with <20 years' practice or surgeons with a preindex volume <700 cases.

CONCLUSIONS

For a technically challenging surgical procedure like off-pump CABG, prior workload adversely affected patient outcomes.

Effect of the biosynthesis of the volatile compound phenylacetaldehyde on chloroplast modifications in tea (Camellia sinensis) plants

Plant volatile compounds have important physiological and ecological functions. Phenylacetaldehyde (PAld), a volatile phenylpropanoid/benzenoid, accumulates in the leaves of tea (Camellia sinensis) plants grown under continuous shading. This study was conducted to determine whether PAld production is correlated with light and to elucidate the physiological functions of PAld in tea plants. Specifically, the upstream mechanism modulating PAld biosynthesis in tea plants under different light conditions as well as the effects of PAld on chloroplast/chlorophyll were investigated. The biosynthesis of PAld was inhibited under light, whereas it was induced in darkness. The structural gene encoding aromatic amino acid aminotransferase 1 (CsAAAT1) was expressed at a high level in darkness, consistent with its importance for PAld accumulation. Additionally, the results of a transcriptional activation assay and an electrophoretic mobility shift assay indicated CsAAAT1 expression was slightly activated by phytochrome-interacting factor 3-2 (CsPIF3-2), which is a light-responsive transcription factor. Furthermore, PAld might promote the excitation of chlorophyll in dark-treated chloroplasts and mediate electron energy transfer in cells. However, the accumulated PAld can degrade chloroplasts and chlorophyll, with potentially detrimental effects on photosynthesis. Moreover, PAld biosynthesis is inhibited in tea leaves by red and blue light, thereby decreasing the adverse effects of PAld on chloroplasts during daytime. In conclusion, the regulated biosynthesis of PAld in tea plants under light and in darkness leads to chloroplast modifications. The results of this study have expanded our understanding of the biosynthesis and functions of volatile phenylpropanoids/benzenoids in tea leaves.

Histone deacetylase CsHDA6 mediates the regulated formation of the anti-insect metabolite α-farnesene in tea (Camellia sinensis)

α-Farnesene accumulated in tea plants following infestations by most insects, and mechanical wounding is the common factor. However, the specific mechanism underlying the wounding-regulated accumulation of α-farnesene in tea plants remains unclear. In this study, we observed that histone deacetylase inhibitor treatment induced the accumulation of α-farnesene. The histone deacetylase CsHDA6 interacted directly with CsMYC2, which was an important transcription factor in the jasmonic acid (JA) pathway, and co-regulated the expression of the key α-farnesene synthesis gene CsAFS. Wounding caused by insect infestation affected CsHDA6 production at the transcript and protein levels, while also inhibited the binding of CsHDA6 to the CsAFS promoter. The resulting increased acetylation of histones H3/H4 in CsAFS enhanced the expression of CsAFS and the accumulation of α-farnesene. In conclusion, our study demonstrated the effect of histone acetylation on the production of tea plant HIPVs and revealed the importance of the CsHDA6-CsMYC2 transcriptional regulatory module.

Involvement of histone deacetylase CsHDA2 in regulating (E)-nerolidol formation in tea (Camellia sinensis) exposed to tea green leafhopper infestation

Herbivore-induced plant volatiles (HIPVs) help the tea plant (Camellia sinensis) adapt to environmental stress, and they are also quality-related components of tea. However, the upstream mechanism regulating the herbivore-induced expression of volatile biosynthesis genes is unclear, especially at the level of epigenetic regulation. In this study, similar to the effects of a tea green leafhopper infestation, treatments with exogenous jasmonic acid (JA) and histone deacetylase inhibitors significantly increased the (E)-nerolidol content in tea and induced the expression of the associated biosynthesis gene CsNES. Furthermore, a key transcription factor related to JA signaling, myelocytomatosis 2 (CsMYC2), interacted with histone deacetylase 2 (CsHDA2) in vitro and in vivo. A tea green leafhopper infestation inhibited CsHDA2 expression and decreased CsHDA2 abundance. Moreover, the tea green leafhopper infestation increased H3 and H4 acetylation levels in the promoter region of CsNES, which in turn upregulated the expression of CsNES and increased the (E)-nerolidol content. In this study, we revealed the effects of histone acetylations on the accumulation of HIPVs, while also confirming that CsHDA2-CsMYC2 is an important transcriptional regulatory module for the accumulation of (E)-nerolidol induced by tea green leafhoppers. The results of this study may be useful for characterizing plant aromatic compounds and the main upstream stress-responsive signaling molecules. Furthermore, the study findings will assist researchers clarify the epigenetic regulation influencing plant secondary metabolism in response to external stress.

Histone H3K27 demethylase SlJMJ4 promotes dark- and ABA- induced leaf senescence in tomato

Leaf senescence is a highly-programmed developmental process during the plant life cycle. ABA plays an important role in leaf senescence. However, the mechanism underlying ABA-mediated leaf senescence, particularly the upstream epigenetic regulatory network, remains largely unclear. Here, we identified that SlJMJ4, a Jumonji C (jmjC) domain-containing protein in tomato, specifically demethylates di- and tri-methylations of lysine 27 of histone H3 (H3K27) in vitro and in vivo. Overexpression of SlJMJ4 results in premature senescence phenotype and promotes dark- and ABA-induced leaf senescence in tomato. Under dark condition, SlJMJ4-promoted leaf senescence is associated with upregulated expression of transcription factors (SlORE1 and SlNAP2) and senescence-associated genes (SlSAG113, SlSAG12) via removal of H3K27me3. In responses to ABA, overexpression of SlJMJ4 increases its binding at the loci of SlORE1, SlNAP2, SlSAG113, SlSAG12, SlABI5 and SlNCED3 and decreases their H3K27me3 levels, and therefore activates their expression and mediates ABA-induced leaf senescence in tomato. Taken together, these results demonstrate that SlJMJ4 plays a positive role in leaf senescence in tomato and is implicated in ABA-induced leaf senescence by binding to many key genes related to ABA synthesis and signaling, transcription regulation and senescence and hence promoting their H3K27me3 demethylation.

Mechanism Underlying the Shading-Induced Chlorophyll Accumulation in Tea Leaves

Besides aroma and taste, the color of dry tea leaves, tea infusion, and infused tea leaves is also an important index for tea quality. Shading can significantly increase the chlorophyll content of tea leaves, leading to enhanced tea leaf coloration. However, the underlying regulatory mechanism remains unclear. In this study, we revealed that the expressions of chlorophyll synthesis genes were significantly induced by shading, specially, the gene encoding protochlorophyllide oxidoreductase (CsPOR). Indoor control experiment showed that decreased light intensity could significantly induce the expression of CsPOR, and thus cause the increase of chlorophyll content. Subsequently, we explored the light signaling pathway transcription factors regulating chlorophyll synthesis, including CsPIFs and CsHY5. Through expression level and subcellular localization analysis, we found that CsPIF3-2, CsPIF7-1, and CsHY5 may be candidate transcriptional regulators. Transcriptional activation experiments proved that CsHY5 inhibits CsPORL-2 transcription. In summary, we concluded that shading might promote the expression of CsPORL-2 by inhibiting the expression of CsHY5, leading to high accumulation of chlorophyll in tea leaves. The results of this study provide insights into the mechanism regulating the improvements to tea plant quality caused by shading.

Feasible strategies for studying the involvement of DNA methylation and histone acetylation in the stress-induced formation of quality-related metabolites in tea (Camellia sinensis)

Tea plants are subjected to multiple stresses during growth, development, and postharvest processing, which affects levels of secondary metabolites in leaves and influences tea functional properties and quality. Most studies on secondary metabolism in tea have focused on gene, protein, and metabolite levels, whereas upstream regulatory mechanisms remain unclear. In this review, we exemplify DNA methylation and histone acetylation, summarize the important regulatory effects that epigenetic modifications have on plant secondary metabolism, and discuss feasible research strategies to elucidate the underlying specific epigenetic mechanisms of secondary metabolism regulation in tea. This information will help researchers investigate the epigenetic regulation of secondary metabolism in tea, providing key epigenetic data that can be used for future tea genetic breeding.

Effect of a smartphone-based intervention on secondary prevention medication prescriptions after coronary artery bypass graft surgery: The MISSION-1 randomized controlled trial

BACKGROUND

Studies found that patients who underwent coronary artery bypass grafting (CABG) often fail to receive optimal evidence-based secondary prevention medications. We evaluated the effectiveness of a smartphone-based quality improvement effort on improving the prescription of medical therapies.

METHODS

In this cluster-randomized controlled trial, 60 hospitals were randomized to a control arm (n = 30) or to an intervention arm using smartphone-based multifaceted quality improvement interventions (n = 30). The primary outcome was the prescription of statin. The secondary outcomes were prescription of beta-blocker, angiotensin-converting enzyme inhibitor, or angiotensin receptor blocker (ACE inhibitor or ARB), and optimal medical therapy for eligible patients.

RESULTS

Between June 1, 2015 and September 15, 2016, a total of 10,006 CABG patients were enrolled (5,653 in 26 intervention and 4,353 in 29 control hospitals, 5 hospitals withdrew). Statin prescribing rate was 87.8% in the intervention arm and 84.4% in the control arm. We saw no evidence of an effect of intervention on statin prescribing in the intention-to-treat analysis (odds ratio [OR], 1.31; 95% confidence interval (CI), 0.68-2.54; P = .43) or in key patient subsets. The prescription rates of ACE inhibitor or ARB and optimal medical therapy were comparable between study groups, while beta-blocker was more often prescribed in the intervention arm. Post hoc analysis demonstrated a greater increase in statin prescribing rate over time in the intervention arm.

CONCLUSIONS

A smartphone-based quality improvement intervention compared with usual care did not increase statin prescribing for patients who received CABG. New studies focusing on the best practice of this technique may be warranted.

Trends of Coronary Artery Bypass Grafting Performance in a Cohort of Hospitals in China Between 2013 and 2018

BACKGROUND

China has witnessed a rapid increase in the volume of coronary artery bypass grafting (CABG) but substantial gaps in the performance for CABG across the nation. The present study aimed to investigate the change in CABG performance after years of quality improvement measures in a national registry in China.

METHODS

The study included 66 971 patients who underwent isolated CABG in a cohort of 74 tertiary hospitals in China between January 2013 and December 2018. Data were collected from the Chinese Cardiac Surgery Registry. Outcomes were in-hospital mortality and postoperative length of stay. Five process measures for surgical technique and secondary prevention were also analyzed. We described the changes in the overall performance and interhospital heterogeneity across the years.

RESULTS

The in-hospital mortality declined from 0.9% in 2013 to 0.6 in 2018, with a risk-adjusted odds ratio of 0.66 (95% CI, 0.46-0.93; P<0.001). The standard mean difference for risk-standardized mortality rate between hospitals in the lowest and highest quartile narrowed from 1.63 in 2013 to 1.35 in 2018. The median (interquartile range) hospital-level rate of using arterial graft increased from 93.9% (86.0%-97.8%) to 94.6% (83.3%-99.2%), but the difference was not statistically significant. Meanwhile, the rate of free from blood transfusion increased from 17.0% (2.6%-32.0%) to 34.1% (8.8%-52.9%). The hospital-level rate of prescribing β-blockers at discharge significantly increased from 82.8% (66.7%-90.3%) to 91.1% (82.1%-97.1%), statin from 75.8% (55.7%-88.9%) to 88.9% (75.0%-96.0%), and aspirin from 90.3% (83.9%-95.2%) to 95.3% (88.9%-98.1%).

CONCLUSIONS

In the Chinese Cardiac Surgery Registry, there were notable improvements in the treatment process related to CABG and decline of in-hospital mortality with reduced interhospital heterogeneity.

Involvement of DNA methylation in regulating the accumulation of the aroma compound indole in tea (Camellia sinensis) leaves during postharvest processing

The manufacturing process of tea (Camellia sinensis), especially oolong tea, involves multiple postharvest stresses. These stresses can induce the formation and accumulation of many important aroma compounds, such as indole-a key floral aroma contributor of oolong tea. However, little is known about the regulation mechanisms of aroma compound formation, especially epigenetic regulation. DNA methylation is an important epigenetic modification. Changes in the DNA methylation levels of promoter sequences can regulate gene expression under stress conditions. In this study, the differences in DNA methylation levels and histone 3 lysine 9 dimethylation levels of indole key biosynthetic gene (tryptophan synthase β-subunit 2, CsTSB2) were detected between untreated and continuous wounding treatment tea leaves. The results show that the DNA methylation levels affect the ability of the basic helix-loop-helix family transcription factor CsMYC2a to bind to the promoter of CsTSB2. Analyses of the transcript levels of DNA methyltransferases during oolong tea processing screened out candidate genes involved in the regulation of secondary metabolite product biosynthesis/accumulation. The results suggest that the domains rearranged methyltransferase 3, a DNA methyltransferase, is involved in the DNA methylation regulation of indole formation during the oolong tea manufacturing process. This is the first report on the involvement of DNA methylation in the regulation of aroma compound formation in tea leaves exposed to postharvest stresses.

Transformation of Salicylic Acid and Its Distribution in Tea Plants (Camellia sinensis) at the Tissue and Subcellular Levels

Salicylic acid (SA) is a well-known immune-related hormone that has been well studied in model plants. However, less attention has been paid to the presence of SA and its derivatives in economic plants, such as tea plants (Camellia sinensis). This study showed that tea plants were rich in SA and responded differently to different pathogens. Feeding experiments in tea tissues further confirmed the transformation of SA into salicylic acid 2-O-β-glucoside (SAG) and methyl salicylate. Nonaqueous fractionation techniques confirmed that SA and SAG were mostly distributed in the cytosol of tea leaves, consistent with distributions in other plant species. Furthermore, the stem epidermis contained more SA than the stem core both in C. sinensis cv. "Jinxuan" (small-leaf species) and "Yinghong No. 9" (large-leaf species). Compared with cv. "Yinghong No. 9", cv. "Jinxuan" contained more SAG in the stem epidermis, which might explain its lower incidence rate of wilt disease. This information will improve understanding of SA occurrence in tea plants and provide a basis for investigating the relationship between SA and disease resistance in tea plants.

Epigenetic Regulation of the Phytohormone Abscisic Acid Accumulation under Dehydration Stress during Postharvest Processing of Tea (Camellia sinensis)

The plant hormone abscisic acid (ABA) accumulates in tea leaves under dehydration stress during the withering process. However, the mechanism underlying ABA biosynthesis regulation remains largely unclear. In the present study, we found increased expression of ABA biosynthesis genes under dehydration stress during postharvest processing of tea. Furthermore, dehydration stress promoted ABA accumulation by increasing histone acetylation of ABA anabolism genes but by decreasing the levels of histone H3 lysine 9 dimethylation and DNA methylation of ABA biosynthesis genes. We screened candidate regulators of histone deacetylation and DNA methylation under dehydration stress. Taken together, our results indicate a role for epigenetic modifications during postharvest processing of tea.

Induced biosynthesis of chlorogenic acid in sweetpotato leaves confers the resistance against sweetpotato weevil attack

Sweetpotato weevil is among the most harmful pests in some major sweetpotato growing areas with warm climates. To enable the future establishment of safe weevil-resistance strategies, anti-weevil metabolites from sweetpotato should be investigated. In the present study, we pretreated sweetpotato leaves with exogenous chlorogenic acid and then exposed them to sweetpotato weevils to evaluate this compound's anti-insect activity. We found that chlorogenic acid applied to sweetpotato conferred significant resistance against sweetpotato-weevil feeding. We also observed enhanced levels of chlorogenic acid in response to weevil attack in sweetpotato leaves. To clarify how sweetpotato weevils regulate the generation of chlorogenic acid, we examined key elements of plant-herbivore interaction: continuous wounding and phytohormones participating in chlorogenic acid formation. According to our results, sweetpotato weevil-derived continuous wounding induces increases in phytohormones, including jasmonic acid, salicylic acid, and abscisic acid. These phytohormones can upregulate expression levels of genes involved in chlorogenic acid formation, such as IbPAL, IbC4H and IbHQT, thereby leading to enhanced chlorogenic acid generation. This information should contribute to understanding of the occurrence and formation of natural anti-weevil metabolites in sweetpotato in response to insect attack and provides critical targets for the future breeding of anti-weevil sweetpotato cultivars.

SWI3B and HDA6 interact and are required for transposon silencing in Arabidopsis

Although the interplay of covalent histone acetylation/deacetylation and ATP-dependent chromatin remodelling is crucial for the regulation of chromatin structure and gene expression in eukaryotes, the underlying molecular mechanism in plants remains largely unclear. Here we show a direct interaction between Arabidopsis SWI3B, an essential subunit of the SWI/SNF chromatin-remodelling complex, and the RPD3/HDA1-type histone deacetylase HDA6 both in vitro and in vivo. Furthermore, SWI3B and HDA6 co-repress the transcription of a subset of transposons. Both SWI3B and HDA6 maintain transposon silencing by decreasing histone H3 lysine 9 acetylation, but increasing histone H3 lysine 9 di-methylation, DNA methylation and nucleosome occupancy. Our findings reveal that SWI3B and HDA6 may act in the same co-repressor complex to maintain transposon silencing in Arabidopsis.

Long-Term Graft Patency After Off-Pump and On-Pump Coronary Artery Bypass: A CORONARY Trial Cohort

BACKGROUND

Randomized controlled trials have compared the early and midterm prognosis of on-pump coronary artery bypass grafting (CABG) and off-pump CABG. However the results are controversial, and there is limited information on graft patency and long-term outcomes.

METHODS

Between May 2007 and October 2011, 349 patients were randomized to off-pump or on-pump CABG as part of the CORONARY trial at Fuwai Hospital. The primary outcome was coronary bypass graft patency, which was assessed at a mean of 6.7 ± 1.7 years after surgery by multidetector computed tomography. A secondary endpoint was a composite outcome of death, nonfatal myocardial infarction, repeat coronary revascularization, or stroke; mean follow-up was 6.5 ± 1.7 years. Graft patency was compared between the off-pump and on-pump CABG treatment arms in 206 patients with follow-up computed tomography.

RESULTS

During the follow-up period 107 patients were in the off-pump CABG group and 99 in the on-pump group. These patients underwent a total of 723 grafts, and the overall rate of graft patency did not differ significantly between the off-pump and on-pump groups (87.4% vs 88.9%, P = .527). The patency rate of the posterior descending branch was lower than average. Higher incidences of mortality, nonfatal myocardial infarction, and repeat revascularization were found in the off-pump patients; however it did not reach significance.

CONCLUSIONS

There were no statistical differences in graft patency rates in off-pump versus on-pump CABG patients during long-term follow-up. The on-pump CABG group appeared to have a better long-term prognosis even with no statistical differences for the limited study population.

Associations between Serum Sex Hormone Concentrations and Telomere Length among U.S. Adults, 1999-2002

BACKGROUND AND OBJECTIVES

Sex hormone concentrations and telomere length are age related responses of human body, while whether there is a direct relation between sex hormone and telomere length is uncertain. Therefore, we used the data of National Health and Nutrition Examination Survey (NHANES) to quantify their direct association.

RESEARCH DESIGN AND METHODS

A total of 710 women aged 35-60 years and 539 men aged 20-85 years were included from two cycles of the NHANES (1999-2002). Telomere length relative to standard reference DNA (T/S ratio) was measured using quantitative polymerase chain reaction method. Seven hormones in serum (5 in men and 2 in women) were assayed. Logistic regressions were used to calculate the odds ratios to evaluate the telomere length-sex hormones association.

RESULTS

Men with vigorous physical activity (71.1%) and without history of cardiovascular diseases, diabetes, and lipid-lowering drugs using tended to have a longer telomere length (all P-values < 0.05); while women with longer sedentary time, smaller pregnant or live birth, and with older ages of firth/last birth were likely with longer telomere length (all P-values < 0.05). After adjusted for potential confounders, only anti-Mullerian hormone was positively and stably associated with short leukocytes telomere length in men (OR: 1.098; 95% CI: 1.034, 1.165). We did not detect any significant association of short telomere length with sex hormones in men and women. Discussion and Implications: Serum anti-Mullerian hormone in men was positively and stably associated with telomere length. More large-scaled and well-designed prospective studies are warranted to reconfirm our conclusions.

HY5 Interacts with the Histone Deacetylase HDA15 to Repress Hypocotyl Cell Elongation in Photomorphogenesis

Photomorphogenesis is a critical plant developmental process that involves light-mediated transcriptome and histone modification changes. The transcription factor ELONGATED HYPOCOTYL5 (HY5) acts downstream of multiple families of photoreceptors to promote photomorphogenesis by regulating the expression of light-responsive genes. However, the molecular mechanism for HY5-mediated transcriptional regulation remains largely unclear. Here, we demonstrated that HY5 directly interacts with a Reduced Potassium Dependence3/Histone Deacetylase1 (HDA1)-type histone deacetylase, HDA15, both in vitro and in vivo. Phenotypic analysis revealed that HDA15 is a negative regulator of hypocotyl cell elongation under both red and far-red light conditions in Arabidopsis (Arabidopsis thaliana) seedlings. The enzymatic activity of HDA15 is required for inhibition of hypocotyl elongation. Furthermore, HDA15 and HY5 act interdependently in the repression of hypocotyl cell elongation in photomorphogenesis. Genome-wide transcriptome analysis revealed that HDA15 and HY5 corepress the transcription of a subset of cell wall organization and auxin signaling-related genes. In addition, HDA15 is required for the function of HY5 in the repression of genes related to hypocotyl cell elongation in Arabidopsis seedlings. Moreover, HY5 recruits HDA15 to the promoters of target genes and represses gene expression by decreasing the levels of histone H4 acetylation in a light-dependent manner. Our study revealed a key transcription regulatory node in which HY5 interacts with HDA15 involved in repressing hypocotyl cell elongation to promote photomorphogenesis.

Elucidation of ( Z)-3-Hexenyl-β-glucopyranoside Enhancement Mechanism under Stresses from the Oolong Tea Manufacturing Process

The enzymatic hydrolysis of glycosidically bound volatiles (GBVs) plays an important role in tea aroma formation during the tea manufacturing process. However, during the enzyme-active manufacturing process of oolong tea, most GBVs showed no reduction, while ( Z)-3-hexenyl-β-glucopyranoside significantly enhanced at the turnover stage. This study aimed to determine the reason for this increase in ( Z)-3-hexenyl-β-glucopyranoside. Continuous wounding stress in the turnover stage did not enhance the expression level of glycosyltransferase 1 ( CsGT1), while it induced a significant increase in the ( Z)-3-hexenol content ( p ≤ 0.05). Furthermore, observing the cell structures of tea leaves exposed to continuous wounding and subcellular localizations of CsGTs suggested that the interaction of ( Z)-3-hexenol (substrate) and CsGT1 (enzyme) was available. In conclusion, both continuous wounding and subcellular localizations led to a ( Z)-3-hexenyl-β-glucopyranoside enhancement mechanism during the oolong tea's turnover stage. These results advance our understanding of GBV formation during the tea manufacturing process and their relationship with the stress from the tea manufacturing process. In addition, the information will help us further evaluate contribution of GBVs to enzymatic formation of oolong tea aroma compounds.

Application of two alternative shutdown severe accident management guideline (SSAMG) entry conditions for CPR1000

Recently, with the development and application of full-scope level 2 probabilistic safety assessment (PSA) method around the world, severe accident phenomena during shutdown and low power conditions have aroused extensive attention in nuclear industry. And the shutdown severe accident management guideline (SSAMG) is claimed to be developed, and the verification of the traditional and alternative entry conditions is the first consideration in this procedure. Thus in this paper, the feasibility of the hot leg pipe temperature and the modified jakob number are analyzed based on a SBO sequence firstly. Subsequently, verification work is conducted under a SBO sequence with pressurizer manhole open and a SBO sequence along with SBLOCA. The results proved the excellent effectiveness of the two parameters to be used as alternative SSAMG entry conditions. Also, a relational figure is constructed based on the results of diverse sequences with various primary system pressure to provide visualized guidance for operators. What's more, the value of modified jakob number which indicates the SSAMG entry is thought to be in the range of 0.5–1.

Arabidopsis Histone Methyltransferase SUVH5 Is a Positive Regulator of Light-Mediated Seed Germination

Plant lifecycle starts from seed germination, which is regulated by various environmental cues and endogenous hormones. Light promotes seed germination mainly by phytochrome B (PHYB) during the initial phase of imbibition, which involves genome-wide light-responsive transcription changes. Recent studies indicated an involvement of multiple epigenetic factors in the control of seed germination. However, few studies have been reported about the role of a histone methyltransferase in light-mediated seed germination process. Here, we identified SUVH5, a histone H3 lysine 9 methyltransferase, as a positive regulator in light-mediated seed germination in Arabidopsis. Loss of function of SUVH5 leads to decreased PHYB-dependent seed germination. RNA-sequencing analysis displayed that SUVH5 regulates 24.6% of light-responsive transcriptome in imbibed seeds, which mainly related to hormonal signaling pathways and developmental processes. Furthermore, SUVH5 represses the transcription of ABA biosynthesis and signal transduction-related genes, as well as a family of DELAY OF GERMINATION (DOG) genes via dimethylation of histone H3 at lysine 9 (H3K9me2) in imbibed seeds. Taken together, our findings revealed that SUVH5 is a novel positive regulator of light-mediated seed germination in Arabidopsis.

Surgeon-Specific Quality Monitoring System for Coronary Artery Bypass Grafting

BACKGROUND

We developed a multidimensional quality monitoring system using an electronic health care records-derived database, and mobile-based reports for individual cardiovascular surgeons.

METHODS

This study included surgeons who performed coronary artery bypass graft surgery at a single center in China from January to December 2015. Patient data were automatically derived from structured electronic health records. Surgeon-specific quality measures included inhospital mortality and morbidity, transfusion-free procedure, use of internal mammary artery, postoperative length of stay, and hospitalization cost. The "technique for order of preference by similarity to ideal solution" method was used to create a composite quality measure and rank surgeons on performance. Surgeons were rated into three categories: the top 20%, middle 20% to 80%, and the bottom 20%. Quality data were delivered to surgeons through mobile-based reports.

RESULTS

Forty surgeons performed 4,288 coronary artery bypass graft surgeries in 2015. For surgeons in the top, middle, and bottom performance categories, there was a trend of increase in risk adjusted inhospital morbidity rate (2.66%, 2.89%, and 3.07%, respectively; p = 0.5101). There were significant differences in the use of internal mammary artery (94.65%, 95.8%, 90.14%, respectively; p < 0.0001), risk-adjusted postoperative length of stay (7.01 days, 7.99 days, and 8.69 days, respectively; p < 0.0001), and hospitalization cost (81.27 thousand yuan, 88.36 thousand yuan, and 102.77 thousand yuan, respectively; p < 0.0001).

CONCLUSIONS

We developed a surgeon-specific quality monitoring system using structured electronic health records-derived database, multidimensional measures, and mobile-based reporting. This system will facilitate quality reporting and peer comparison, and strengthen the effect of quality improvement.

Neuronal Activity of the Medulla Oblongata Revealed by Manganese-Enhanced Magnetic Resonance Imaging in a Rat Model of Gastroesophageal Reflux-Related Cough

We investigated neuronal activity of the medulla oblongata during gastroesophageal reflux-related cough (GERC). A rat model of GERC was generated by perfusing HCl into lower esophagus and inducing cough with citric acid. The HCl group rat was received HCl perfusion without citric acid-induced cough. The saline control rat was perfused with saline instead and cough was induced. Citric acid-induced cough rat was only induced by citric acid. Blank group rats were fed normally. Fos expressions were observed in medulla oblongata nuclei using immunohistochemistry. Manganese-enhanced magnetic resonance imaging (MEMRI) was performed to detect the Mn(2+) signal following intraperitoneal injection of MnCl(2). HCl perfusion and citric acid-induced cough caused Fos expressions in the nucleus of solitary tract (nTS), dorsal motor nucleus of the vagus (DMV), paratrigeminal nucleus (Pa5), and intermediate reticular nucleus (IRt), which was higher than HCl group, saline control group, citric acid-induced cough group, and blank group. A high Mn(2+) signal was also observed in most of these nuclei in model rats, compared with blank group animals. The Mn(2+) signal was also higher in the HCl, saline and citric acid-induced cough group animals, compared with blank group animals. The study showed medulla oblongata neurons were excited in a HCl perfusion and citric acid-induced cough rat model, and nTS, DMV, Pa5 and IRt neurons maybe involved in the cough process and signal integrate.

Accuracy and reliability of digital craniofacial measurements using a small-format, handheld 3D camera

OBJECTIVES

Craniofacial assessments often involve three-dimensional facial imaging using an expensive camera with 6 SLR lenses to analyse the positions and relations of anatomic landmarks. Recently, a 3D small-format, handheld camera was developed; however, the accuracy and reliability of this system are largely unknown. The purpose of this study was to evaluate the accuracy and reliability of this system.

MATERIALS & METHODS

A total of 30 sets of evaluations were completed by 2 examiners on 5 human subjects, using 3 different methods: direct callipers, 3D handheld camera and conventional tripod 3D camera images. Each evaluation included 29 anthropometric landmarks that were used as reference points for facial analysis. Two examiners marked the landmarks directly on the faces and measured linear distances using the 3 measurement methods.

RESULTS

Accuracy analysis was performed for handheld vs direct calliper vs conventional camera measurements. Each of these analyses yielded a grand mean of correlation coefficients of .98. Bias measurements revealed that the handheld and conventional camera methods yielded larger measurements than direct callipers (with a mean difference of 1.74, 1.56 mm, respectively, for rater 1 and 0.94, 1.02 mm, respectively, for rater 2). When compared to one another, both the handheld camera and the conventional camera methods yielded similar values for most measurements, with the average overall difference between these modalities of 0.03 mm for rater 1 and 0.07 mm for rater 2.

CONCLUSIONS

The 3D handheld camera showed high accuracy and reliability in comparison with traditional models, indicating that this system may provide a useful tool in craniofacial anthropometry.

Dorsal Vagal Complex Modulates Neurogenic Airway Inflammation in a Guinea Pig Model With Esophageal Perfusion of HCl

Neurogenic airway inflammation in chronic cough and bronchial asthma related to gastroesophageal reflux (GER) is involved in the esophageal–bronchial reflex, but it is unclear whether this reflex is mediated by central neurons. This study aimed to investigate the regulatory effects of the dorsal vagal complex (DVC) on airway inflammation induced by the esophageal perfusion of hydrochloric acid (HCl) following the microinjection of nuclei in the DVC in guinea pigs. Airway inflammation was evaluated by measuring the extravasation of Evans blue dye (EBD) and substance P (SP) expression in the airway. Neuronal activity was indicated by Fos expression in the DVC. The neural pathways from the lower esophagus to the DVC and the DVC to the airway were identified using DiI tracing and pseudorabies virus Bartha (PRV-Bartha) retrograde tracing, respectively. HCl perfusion significantly increased plasma extravasation, SP expression in the trachea, and the expression of SP and Fos in the medulla oblongata nuclei, including the nucleus of the solitary tract (NTS) and the dorsal motor nucleus of the vagus (DMV). The microinjection of glutamic acid (Glu) or exogenous SP to enhance neuronal activity in the DVC significantly potentiated plasma extravasation and SP release induced by intra-esophageal perfusion. The microinjection of γ-aminobutyric acid (GABA), lidocaine to inhibit neuronal activity or anti-SP serum in the DVC alleviated plasma extravasation and SP release. In conclusion, airway inflammation induced by the esophageal perfusion of HCl is regulated by DVC. This study provides new insight for the mechanism of airway neurogenic inflammation related to GER.

Identification of HDA15-PIF1 as a key repression module directing the transcriptional network of seed germination in the dark

Light is a major external factor in regulating seed germination. Photoreceptor phytochrome B (PHYB) plays a predominant role in promoting seed germination in the initial phase after imbibition, partially by repressing phytochrome-interacting factor1 (PIF1). However, the mechanism underlying the PHYB-PIF1-mediated transcription regulation remains largely unclear. Here, we identified that histone deacetylase15 (HDA15) is a negative component of PHYB-dependent seed germination. Overexpression of HDA15 in Arabidopsis inhibits PHYB-dependent seed germination, whereas loss of function of HDA15 increases PHYB-dependent seed germination. Genetic evidence indicated that HDA15 acts downstream of PHYB and represses seed germination dependent on PIF1. Furthermore, HDA15 interacts with PIF1 both in vitro and in vivo. Genome-wide transcriptome analysis revealed that HDA15 and PIF1 co-regulate the transcription of the light-responsive genes involved in multiple hormonal signaling pathways and cellular processes in germinating seeds in the dark. In addition, PIF1 recruits HDA15 to the promoter regions of target genes and represses their expression by decreasing the histone H3 acetylation levels in the dark. Taken together, our analysis uncovered the role of histone deacetylation in the light-regulated seed germination process and identified that HDA15-PIF1 acts as a key repression module directing the transcription network of seed germination.

High activity and negative apparent activation energy in low-temperature CO oxidation – present on Au/Mg(OH)2, absent on Au/TiO2

Aiming at a better understanding of the unusual low-temperature CO oxidation reaction behavior on Au/Mg(OH)₂ catalysts, we investigated this reaction mainly by combined kinetic and in situ IR spectroscopy measurements over a wide range of temperatures, from −90 °C to 200 °C.

Collaborative meta-analysis of individual participant data from observational studies of Lp-PLA2 and cardiovascular diseases

BACKGROUND

A large number of observational epidemiological studies have reported generally positive associations between circulating mass and activity levels of lipoprotein-associated phospholipase A2 (Lp-PLA2) and the risk of cardiovascular diseases. Few studies have been large enough to provide reliable estimates in different circumstances, such as in different subgroups (e.g., by age group, sex, or smoking status) or at different Lp-PLA2 levels. Moreover, most published studies have related disease risk only to baseline values of Lp-PLA2 markers (which can lead to substantial underestimation of any risk relationships because of within-person variability over time) and have used different approaches to adjustment for possible confounding factors.

OBJECTIVES

By combination of data from individual participants from all relevant observational studies in a systematic 'meta-analysis', with correction for regression dilution (using available data on serial measurements of Lp-PLA2), the Lp-PLA2 Studies Collaboration will aim to characterize more precisely than has previously been possible the strength and shape of the age and sex-specific associations of plasma Lp-PLA2 with coronary heart disease (and, where data are sufficient, with other vascular diseases, such as ischaemic stroke). It will also help to determine to what extent such associations are independent of possible confounding factors and to explore potential sources of heterogeneity among studies, such as those related to assay methods and study design. It is anticipated that the present collaboration will serve as a framework to investigate related questions on Lp-PLA2 and cardiovascular outcomes.

METHODS

A central database is being established containing data on circulating Lp-PLA2 values, sex and other potential confounding factors, age at baseline Lp-PLA2 measurement, age at event or at last follow-up, major vascular morbidity and cause-specific mortality. Information about any repeat measurements of Lp-PLA2 and potential confounding factors has been sought to allow adjustment for possible confounding and correction for regression dilution. The analyses will involve age-specific regression models. Synthesis of the available observational studies of Lp-PLA2 will yield information on a total of about 15 000 cardiovascular disease endpoints.

The value of eosinophil VCS parameters in predicting hepatotoxicity of antituberculosis drugs

INTRODUCTION

Drug-induced liver injury (DILI) is the most frequent cause of discontinuation of antituberculosis medication and difficult to predict. In recent years, liver eosinophilia has been associated with incidence of DILI. We hypothesize that morphologic changes in reactive eosinophils associated with DILI may be determined by LH750 (Beckman Coulter, Fullerton, CA) with VCS technology.

METHODS

The absolute eosinophil (AEC), percentage of eosinophil (EOSI%), VCS parameters, and standard deviation (SD) of 500 health controls, 376 patients without DILI, and 50 DILI patients were compared in terms of diagnostic sensitivity and specificity for DILI.

RESULTS

In DILI patients, the increased mean eosinophil volume (MEV) and size variability (MEV-SD) were observed prior to alanine aminotransferase (ALT) elevations. The MEV was correlated well with ALT after therapy. The ROC curve analyses revealed that the MEV and MEV-SD had larger areas under curves (0.894, 0.815, in the week prior to DILI) compared to other parameters. Using a cutoff of 163.15 fL for the MEV and a cutoff of 17.11 for MEV-SD, the sensitivities of 81% and 72% and specificities of 82% and 80% were achieved, respectively, which are higher than other parameters prior to DILI occurred.

CONCLUSIONS

The MEV with size variability (MEV-SD) is a quantitative, objective, and more sensitive parameter and has a potential to be an additional indicator for DILI.

Involvement of rice histone deacetylase HDA705 in seed germination and in response to ABA and abiotic stresses

Histone acetylation and deacetylation play crucial roles in the modification of chromatin structure and regulation of gene expression in eukaryotes. Histone acetyltransferases (HATs) and histone deacetylases (HDACs) assist to maintain the balance of chromatin acetylation status. Previous studies showed that plant HDACs are key regulators involved in response to development and stresses. In this study, we examined the expression pattern and function of HDA705, a member of the RPD3/HDA1-type HDAC in rice. Overexpression of HDA705 in rice decreased ABA and salt stress resistance during seed germination. Delayed seed germination of HDA705 overexpression lines was associated with down-regulated expression of GA biosynthetic genes and up-regulation of ABA biosynthetic genes. Moreover, overexpression of HDA705 in rice enhanced osmotic stress resistance during the seedling stage. Our findings demonstrate that HDA705 may play a role in regulating seed germination and the response to abiotic stresses in rice.