[Bibliometrics Analysis of Studies on Hypertrophic Cardiomyopathy From 2018 to 2022].

Objective To analyze the research progress and hot topics in hypertrophic cardiomyopathy from 2018 to 2022.Methods The publications in the field of hypertrophic cardiomyopathy from January 1,2018 to December 31,2022 were retrieved from Web of Science core collection database and included for a bibliometric analysis.Results A total of 6355 publications were included,with an average citation frequency of 7 times.The year 2021 witnessed the most publications (1406).The analysis with VOSviewer showed that the research on sudden death related to hypertrophic cardiomyopathy,especially the predictive value of late gadolinium-enhanced cardiac MRI in sudden death,was a hot topic.In addition,gene detection and the new drug mavacamten became hot research topics.The United States was the country with the largest number of publications and the highest citation frequency in this field.Chinese scholars produced the second largest number of publications,which,however,included few high-quality research results.Conclusions Risk stratification and prevention of sudden death is still an important and hot research content in the field of hypertrophic cardiomyopathy.Chinese scholars should carry out multi-center cooperation in the future to improve the research results.

Analysis and evaluation of patient-specific three-dimensional printing in complex septal myectomy.

OBJECTIVES: This study aimed to assess the effectiveness of three-dimensional printing (3DP) in patients with complex hypertrophic cardiomyopathy requiring combined transaortic and transapical septal myectomy. METHODS: We created 3DP models for 7 patients undergoing this surgery approach between June and October 2022 using silicone-like resin and conducted mock operations. The models were compared with echocardiography to identify abnormal muscle bundles and heart structures. These patients were then compared with a 1:2 matched group without 3DP, considering age, sex and additional operations. RESULTS: The models mostly presenting with midventricular obstruction showed high consistency with original computed tomography data (r = 0.978, P < 0.001). 3DP identified more abnormal muscle bundles than echocardiography, primarily between the interventricular septum and apex. Excised specimens in mock operations mirrored those in actual myectomies. While cardiopulmonary bypass time was not significantly different, a near-20-min decrease was observed in the 3DP group (135.5 ± 31.1 vs 154.4 ± 36.6 min, P = 0.054). CONCLUSIONS: While no significant differences in surgical outcomes were observed, 3DP appeared to enhance the visualization and understanding of spatial structures (average Likert scale score 4.0), potentially contributing to surgical proficiency (overall rating score 3.9). The use of 3DP may offer additional value in the preparation and execution of operations for complex hypertrophic cardiomyopathy cases.

Mitral annular calcification in obstructive hypertrophic cardiomyopathy: Incidence, risk factors, and prognostic value after myectomy.

BACKGROUND: Mitral annular calcification (MAC) is a risk factor for cardiac surgery, but there is limited study on the prognosis value and the impact for valve function of MAC based on computed tomography (CT) diagnosis after myectomy for hypertrophic obstructive cardiomyopathy (OHCM). METHODS: Consecutive OHCM patients underwent septal myectomy were compared according to the existence of MAC and its severity in preoperative CT scans. The survival data were evaluated and compared by Kaplan Meier analysis and log rank test. Cox regression analysis was used to evaluate the impact of MAC on endpoint events. RESULTS: From the entire cohort of 1035 patients, 10.8% had MAC. In multivariate regression, female (OR = 2.23), age (OR = 1.07), aortic annular calcification (OR = 2.52), aortic calcification (OR = 2.56), systolic anterior motion of the mitral valve (SAM) (OR = 0.42), mitral valve thickening (OR = 2.13), and tricuspid regurgitation (OR = 3.12) were independent predictors of MAC. All-cause mortality (3.57% vs. 1.08%, p = 0.031), major adverse cardiovascular and cerebrovascular events (MACCE) (23.32% vs. 13.65%, p = 0.014), recurrent MR > 2+ (8.04% vs. 2.49%, p = 0.001) and NYHA III-IV (11.61% vs. 5.53%, p = 0.012) were more frequent in OHCM patients with MAC after myectomy. MAC was discovered to be an independent predictor of postoperative recurrent MR > 2+ after other risk factors were taken into account (HR 2.47, 95% CI 1.08-5.67, p = 0.0329). Moderate-to-severe MAC was an independent risk factor (HR 2.03, 95% CI 1.09-3.75, p = 0.0244) for long-term major adverse cardiovascular and cerebrovascular events (MACCE). CONCLUSION: MAC was detected in one-tenth of OHCM patients in preoperative CT scanning and is mainly associated with aging and atherosclerosis. OHCM patients with MAC had a worse prognosis and more recurrent mitral valve regurgitation than those without MAC after septal myectomy.

High-Burden Premature Atrial Contractions Predict New-Onset Atrial Fibrillation After Surgical Septal Myectomy.

Although increased premature atrial contractions (PACs) reportedly predict atrial fibrillation (AF) in both general and specific (e.g., patients with stroke) populations, early postoperative AF (POAF) risk in patients with increased PAC burden who require cardiac surgery remains unclear. We examined the correlation between different preoperative PAC burdens and POAF in patients with obstructive hypertrophic cardiomyopathy (OHCM) who underwent surgical treatment. We analyzed 304 consecutively admitted patients with OHCM without previous AF who underwent isolated septal myectomy between January 2015 and December 2018. All patients underwent preoperative 24-hour Holter electrocardiogram monitoring. PACs were present in 259 patients (85.20%) and absent in 45 patients (14.80%). According to the cut-off PAC number of 100 beats/24 hours, there were 211 patients (69.41%) with low-burden PACs and 48 patients (15.79%) with high-burden PACs. AF after septal myectomy occurred in 73 patients, which consisted of 3/45 in the non-PAC group (6.67%), 47/211 in the low-PAC-burden group (22.27%), and 23/48 in the high PAC burden group (47.92%). POAF incidence was higher in both low- and high-burden patients than in patients without PAC (p <0.01). Multivariate logistic regression analyses demonstrated that high-burden PACs (p = 0.02) and age (p <0.01) but not low-burden PACs (p = 0.22) independently predicted POAF in patients with OHCM. The area under the receiver operating characteristic curve for preoperative PACs was 0.72 (95% confidence interval 0.66 to 0.79, p <0.01, sensitivity: 68.49%, specificity: 69.26%). In conclusion, POAF incidence was significantly higher in patients with preoperative high-burden PACs and can predict POAF in patients with OHCM.

Influence of Preoperative Serum Albumin on Acute Kidney Injury after Aortic Surgery for Acute Type A Aortic Dissection: A Retrospective Cohort Study.

There are relatively few articles on the relationship between serum albumin and acute kidney injury (AKI). Therefore, the objective of this research was to study the relationship between serum albumin and AKI in patients who were undergoing surgery for acute type A aortic dissection. METHODS: We retrospectively collected data from 624 patients attending a Chinese hospital between January 2015 and June 2017. The target independent variable was serum albumin measured before surgery after hospital admission, and the dependent variable was AKI, defined in accordance with the Kidney Disease Improving Global Outcomes (KDIGO) criteria. RESULTS: The mean age of these 624 selected patients was 48.5 ± 11.1 years, and almost 73.7% were male. A nonlinear association was detected between serum albumin and AKI; the turning point was 32 g/L. The risk of AKI decreased gradually as the serum albumin level increased up to 32 g/L (adjusted OR = 0.87; 95% CI 0.82-0.92; p < 0.001). When the serum albumin level exceeded 32 g/L, the level of serum albumin was not associated with the risk of AKI (OR = 1.01, 95% CI 0.94-1.08; p = 0.769). CONCLUSIONS: The findings suggest that preoperative serum albumin below 32 g/L was an independent risk factor for AKI in patients undergoing surgery for acute type A aortic dissection. TRIAL REGISTRATION: A retrospective cohort study.

New insights into metabolomics profile generation in fermented tea: the relevance of bacteria and metabolites in Fuzhuan brick tea.

BACKGROUND: The contribution of bacteria to fermented tea is not clear and the associated research is relatively limited. To reveal the role of microorganisms in fermented tea processing, the microbial community and metabolites of Fuzhuan brick tea (FBT), a Chinese traditional fermented tea, were revealed via high-throughput sequencing and liquid chromatography-mass spectrometry (LC-MS). RESULTS: In FBT, bacterial communities had a higher abundance and diversity, Lactococcus and Bacillus were the main bacteria, and Eurotium was the predominant fungus. The predictive metabolic function indicated the pathways of cellular growth, environmental information, genetics and material metabolism of bacterial communities were abundant, whereas the fungal community predictive metabolic function was almost saprotroph. Using LC-MS, 1143 and 536 metabolites were defined in positive and negative ion mode, respectively. There were essential correlations between bacterial populations and metabolites, such that Bacillus was correlated significantly with 44 metabolites (P < 0.05) and Enterococcus was significantly associated with 15 metabolites (P < 0.05). Some of the main active components were significantly correlated with the bacteria, such as Enterococcus, Lactococcus and Carnobacterium. CONCLUSION: Not only Eurotium, but also the bacteria were involved in the changes of metabolomics profile in fermented FBT. The present study assists in providing new insights into metabolomics profile generation in fermented tea. The present research lays a foundation for controlling the FBT fermentation by artificial inoculation to improve quality. © 2021 Society of Chemical Industry.

Fragment-Guided Discovery of Pyrazole Carboxylic Acid Inhibitors of the Kelch-like ECH-Associated Protein 1: Nuclear Factor Erythroid 2 Related Factor 2 (KEAP1:NRF2) Protein-Protein Interaction.

The NRF2-mediated cytoprotective response is central to cellular homoeostasis, and there is increasing interest in developing small-molecule activators of this pathway as therapeutics for diseases involving chronic oxidative stress. The protein KEAP1, which regulates NRF2, is a key point for pharmacological intervention, and we recently described the use of fragment-based drug discovery to develop a tool compound that directly disrupts the protein-protein interaction between NRF2 and KEAP1. We now present the identification of a second, chemically distinct series of KEAP1 inhibitors, which provided an alternative chemotype for lead optimization. Pharmacophoric information from our original fragment screen was used to identify new hit matter through database searching and to evolve this into a new lead with high target affinity and cell-based activity. We highlight how knowledge obtained from fragment-based approaches can be used to focus additional screening campaigns in order to de-risk projects through the rapid identification of novel chemical series.

In vitro and in vivo induction of fetal hemoglobin with a reversible and selective DNMT1 inhibitor.

Pharmacological induction of fetal hemoglobin (HbF) expression is an effective therapeutic strategy for the management of beta-hemoglobinopathies such as sickle cell disease. DNA methyltransferase (DNMT) inhibitors 5-azacytidine (5-aza) and 5-aza-2'-deoxycytidine (decitabine) have been shown to induce fetal hemoglobin expression in both preclinical models and clinical studies, but are not currently approved for the management of hemoglobinopathies. We report here the discovery of a novel class of orally bioavailable DNMT1-selective inhibitors as exemplified by GSK3482364. This molecule potently inhibits the methyltransferase activity of DNMT1, but not DNMT family members DNMT3A or DNMT3B. In contrast with cytidine analog DNMT inhibitors, the DNMT1 inhibitory mechanism of GSK3482364 does not require DNA incorporation and is reversible. In cultured human erythroid progenitor cells (EPCs), GSK3482364 decreased overall DNA methylation resulting in de-repression of the gamma globin genes HBG1 and HBG2 and increased HbF expression. In a transgenic mouse model of sickle cell disease, orally administered GSK3482364 caused significant increases in both HbF levels and in the percentage HbF-expressing erythrocytes, with good overall tolerability. We conclude that in these preclinical models, selective, reversible inhibition of DNMT1 is sufficient for the induction of HbF, and is well-tolerated. We anticipate that GSK3482364 will be a useful tool molecule for the further study of selective DNMT1 inhibition both in vitro and in vivo.

Are dilated ascending aortas of Chinese patients more likely to dissect?

BACKGROUND: Ascending aortic aneurysm is a disease requiring surgical intervention. However, the timing of operation is still controversial. The purpose of this study is to compare the ascending aortic diameter and postoperative outcomes in hospital between patients with simple ascending aortic dissection and patients with simple ascending aortic dilation in China, and to investigate the accuracy of the timing of operation determined by ascending aortic diameter alone. METHODS: We reviewed the data from 2,520 hospitalized patients of aortic aneurysm and aortic dissection who underwent surgical treatment from January 2010 to June 2017 in our hospital. A total of 139 simple ascending aortic dissection and simple ascending aortic aneurysm hospitalized patients excluding Marfan syndrome and heart valve diseases etc. (56 in the aortic dilatation group and 83 in the aortic dissection group) were enrolled. The t-test and univariable analysis were used to compare the differences between two groups. RESULTS: For the aortic diameter, the group of aneurysm has greater ascending aortic diameter and the index of ascending aortic diameter compared with the group of dissection (P<0.001, P<0.001). For male patients, the result is the same (P<0.001, P<0.001). But for female patients, there was no significant statistical significance between the two groups (P=0.631, P=0.288). For the postoperative outcomes, the dissection group had higher mortality, incidence of tracheotomy and postoperative re-exploration for hemorrhage (P=0.040, P=0.011, P=0.028). CONCLUSIONS: The majority of patients with simple ascending aortic dissection present with aortic diameters <5.5 cm and this is not consistent with the current operation indications of aortic aneurysm. It is far from enough to predict aortic dissection with aortic diameter alone. More indicators are needed to do this.

Does preoperative serum creatinine affect the early surgical outcomes of acute Stanford type A aortic dissection?

BACKGROUND: Acute Stanford type A aortic dissection is a lethal disease requiring surgery. Evidence regarding the effects of preoperative creatinine in mortality is limited, and few studies have evaluated the effect of postoperative dialysis treatment on it. METHODS: In this cohort study, we continuously recruited 632 surgical patients who were treated for acute type A aortic dissection in our hospital between January 2015 and May 2017. The preoperative level of serum creatinine was measured. All patients were followed up after surgery for 30 days to determine early mortality. RESULTS: The 30-day mortality after surgery increased with elevated levels of preoperative serum creatinine. Median (interquartile range) serum creatinine levels in survivors were 9.61 µmol/dL (7.28-12.62 µmol/dL) versus 13.41 µmol/dL (10.28-20.63 µmol/dL) in death (p < 0.01). Adjusted odds ratios for increasing per µmol/dL serum creatinine were 1.09 (95% confidence interval, 1.03-1.15). We also found that the effect of preoperative creatinine on 30-day mortality was diminished by dialysis treatment after surgery. CONCLUSION: Preoperative serum creatinine predicts outcome in patients undergoing surgery for Stanford type A aortic dissection, and postoperative dialysis treatment can reduce its hazard.

Increased frequency of FBN1 frameshift and nonsense mutations in Marfan syndrome patients with aortic dissection.

BACKGROUND: Marfan syndrome (MFS) is an inherited connective tissue disease that mainly involves Fibrillin-1 (FBN1) mutations and aortic manifestations. In this study, we investigated the correlations between the FBN1 genotype-phenotype and aortic events (aortic dissection and aortic aneurysm) in patients with Marfan syndrome. METHODS: Genotype and phenotype information was evaluated in 180 patients with MFS. DNA sequencing was performed on each patient. According to the clinical manifestation, these patients were split into two groups: the aortic dissection group and the aortic aneurysm group. Aortic wall tissue was obtained from Marfan patients who underwent surgery and was used for staining. RESULTS: A total of 180 patients with FBN1 mutations were grouped into four categories: 90 with missense mutations, 32 with splicing mutations, 29 with frameshift mutations, and 29 with nonsense mutations. There was a significantly higher frequency of frameshift and nonsense mutations observed in aortic dissection than in aortic aneurysm (25.58% vs. 4.35%, p = .005; 25.58% vs. 8.70%, p = .033, respectively;), while missense mutations showed a higher frequency in aortic aneurysm than in aortic dissection (69.57% vs. 32.56%, respectively; p < .001) and a higher rate of lens dislocation (34.78% vs. 13.95%, respectively; p = .008). Pathological staining showed that elastic fibers were sparser in patients with a frameshift and nonsense mutations, and the smooth muscle cells were sparser and more disorganized than those observed in patients with missense mutations. CONCLUSION: This study showed that FBN1 gene frameshift and nonsense mutations are more common in patients with aortic dissection and may have meaningful guidance for the treatment of Marfan syndrome patients.

MrgX2 is a promiscuous receptor for basic peptides causing mast cell pseudo-allergic and anaphylactoid reactions.

Activation of MrgX2, an orphan G protein-coupled receptor expressed on mast cells, leads to degranulation and histamine release. Human MrgX2 binds promiscuously to structurally diverse peptides and small molecules that tend to have basic properties (basic secretagogues), resulting in acute histamine-like adverse drug reactions of injected therapeutic agents. We set out to identify MrgX2 orthologues from other mammalian species used in nonclinical stages of drug development. Previously, the only known orthologue of human MrgX2 was from mouse, encoded by Mrgprb2. MrgX2 genes of rat, dog (beagle), minipig, pig, and Rhesus and cynomolgus monkey were identified by bioinformatic approaches and verified by their ability to mediate calcium mobilization in transfected cells in response to the classical MrgX2 agonist, compound 48/80. The peptide GSK3212448 is an inhibitor of the PRC2 epigenetic regulator that caused profound anaphylactoid reactions upon intravenous infusion to rat. We showed GSK3212448 to be a potent MrgX2 agonist particularly at rat MrgX2. We screened sets of drug-like molecules and peptides to confirm the highly promiscuous nature of MrgX2. Approximately 20% of drug-like molecules activated MrgX2 (pEC50 ranging from 4.5 to 6), with the principle determinant being basicity. All peptides tested of net charge +3 or greater exhibited agonist activity, including the cell penetrating peptides polyarginine (acetyl-Arg9-amide) and TAT (49-60), a fragment of HIV-1 TAT protein. Finally, we showed that the glycopeptide antibiotic vancomycin, which is associated with clinical pseudo-allergic reactions known as red man syndrome, is an agonist of MrgX2.

Protocol for creation of a risk scoring system for acute type A aortic dissection surgery.

Stanford type A aortic dissection is a kind of cardiovascular disease which seriously threatens human life and health. It has the characteristics of rapid onset, rapid progress and high mortality. Surgical treatment is a recognized treatment for type A aortic dissection. There are many disputed places in the actual clinical work about the timing, prognosis and methods of the operation. This study aims to establish an early mortality risk scoring system for acute Stanford A aortic dissection surgery patients. METHODS AND ANALYSIS: The structured data of patients with acute type A aortic dissection were collected. The primary outcome is death during hospitalization. Secondary outcomes will include re-operation and related complications. A risk scoring system of patients with acute type A aortic dissection undergoing surgical treatment will be established. Prospective data will be used to validate the risk stratification ability and accuracy of the model in operative risk prediction.

Comparison of prognostic ability of perioperative myocardial biomarkers in acute type A aortic dissection.

Stanford type A aortic dissection (AD) is a lethal disease requiring surgery. Evidence regarding the prognostic ability of perioperative myocardiac markers on long-term outcome is limited.In this cohort study, we measured perioperative myocardiac markers level in 583 surgical patients with type A AD in our hospital between 2015 and 2017. All patients were followed up after surgery for a median period of 864 days to determine short- and long-term mortality.About one-fifth of patients has a positive preoperative myocardial markers, which was increased significantly after operation. Increase log10 post-creatine kinase MB isoenzyme (CK-MB) (hazard ratio [HR], 4.64; 95% confidence interval [CI] 1.89-11.43; P = .0008), log10 post-TnI (HR, 3.11; 95% CI 1.56-6.21; P = .0013), log10 post-Mb (HR, 3.00; 95% CI 1.40-6.43; P = .0048), log10 pre-CK-MB (HR,1.82; 95% CI 1.03-3.21; P = .0377), and upper tertile of post-CK-MB (HR,1.52; 95% CI 1.05-2.20; P = .0261) were the independent risk factor for 30 days mortality adjusted for potential confounders. None of cardiac markers was significantly associated with long-term outcome independent of other factors.Perioperative myocardiac predicts early outcome in type A AD patients undergoing surgery. Increasing perioperative myocardial markers do not appear to be a predictor for long-term all-cause mortality.

Bioinformatics analysis of the regulatory lncRNA­miRNA­mRNA network and drug prediction in patients with hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) is a complex inherited cardiovascular disease. The present study investigated the long noncoding (lnc)RNA/microRNA (mi)RNA/mRNA expression pattern of patients with HCM and aimed to identify key molecules involved in the development of this condition. An integrated strategy was conducted to identify differentially expressed miRNAs (DEmiRs), differentially expressed lncRNAs (DElncs) and differentially expressed genes (DEGs) based on the GSE36961 (mRNA), GSE36946 (miRNA), GSE68316 (lncRNA/mRNA) and GSE32453 (mRNA) expression profiles downloaded from the Gene Expression Omnibus datasets. Bioinformatics tools were employed to perform function and pathway enrichment analysis, protein­protein interaction, lncRNA­miRNA­mRNA and hub gene networks. Subsequently, DEGs were used as targets to predict drugs. The results indicated that a total of 2,234 DElncs (1,120 upregulated and 1,114 downregulated), 5 DEmiRs (2 upregulated and 3 downregulated) and 42 DEGs (35 upregulated and 7 downregulated) were identified in 4 microarray profiles. Gene ontology analysis revealed that DEGs were mainly involved in actin filament and stress fiber formation and in calcium ion binding, whereas Kyoto Encyclopedia of Genes and Genomes pathway analysis identified the hypoxia inducible factor­1, transforming growth factor­ß and tumor necrosis factor signaling pathways as the main pathways involved in these processes. The hub genes were screened using cytoHubba. A total of 1,086 lncRNA­miRNA­mRNA interactions including 67 lncRNAs, 5 miRNAs and 25 mRNAs were mined in the present study based on prediction websites. Drug prediction indicated that the targeted drugs mainly included angiotensin converting enzyme inhibitors or ß­blockers. A comprehensive bioinformatics analysis of the molecular regulatory lncRNA­miRNA­mRNA network was performed and potential therapeutic applications of drugs were predicted in HCM patients. The data may unravel the future molecular mechanism of HCM.

Cardiopulmonary bypass time is an independent risk factor for acute kidney injury in emergent thoracic aortic surgery: a retrospective cohort study.

BACKGROUND: Thoracic aortic surgery and cardiopulmonary bypass are both associated with development of postoperative acute kidney injury. In this study, we undertook to investigate the relationship between cardiopulmonary bypass time and postoperative acute kidney injury in patients undergoing thoracic aortic surgery for acute DeBakey Type I aortic dissection. METHODS: All patients receiving thoracic aortic surgery for acute DeBakey Type I aortic dissection in Beijing Anzhen hospital from December 2015 to April 2017 were included. Cardiopulmonary bypass time was recorded during surgery. Acute kidney injury was defined based on the Kidney Disease Improving Global Outcomes criteria. A total of 115 consecutive patients were eventually analyzed. RESULTS: The overall incidence of acute kidney injury was 53.0% (n = 61). The average age was 47.8 ± 10.7 years; 74.8% were male. Mean cardiopulmonary bypass time was 211 ± 56 min. In-hospital mortality was 7.8%. Multivariate logistic regression revealed that cardiopulmonary bypass time was independently associated with the occurrence of postoperative acute kidney injury after adjust confounding factors (odds ratio = 1.171; 95% confidence interval: 1.002-1.368; P = 0.047). CONCLUSIONS: Cardiopulmonary bypass time is independently associated with an increased hazard of acute kidney injury after thoracic aortic surgery for acute DeBakey Type I aortic dissection. Further understanding of the mechanism of this association is crucial to the design of preventative strategies.

Deep Hypothermic Circulatory Arrest Does Not Show Better Protection for Vital Organs Compared with Moderate Hypothermic Circulatory Arrest in Pig Model.

BACKGROUND: Continued debates exist regarding the optimal temperature during hypothermic circulatory arrest in aortic arch repair for patients with type A aortic dissection. This study seeks to examine whether the use of moderate hypothermic circulatory arrest in a pig model provides comparable vital organ protection outcomes to the use of deep hypothermic circulatory arrest. METHODS: Thirteen pigs were randomly assigned to 30 minutes of hypothermic circulatory arrest without cerebral perfusion at 15°C (n = 5), 25°C (n = 5), and a control group (n = 3). The changes in standard laboratory tests and capacity for protection against apoptosis in different vital organs were monitored with different temperatures of hypothermic circulatory arrest management in pig model to determine which temperature was optimal for hypothermic circulatory arrest. RESULTS: There were no significant differences in the capacity for protection against apoptosis in vital organs between 2 groups (p > 0.05, respectively). Compared with the moderate hypothermic circulatory arrest group, the deep hypothermic circulatory arrest group had no significant advantages in terms of the biologic parameters of any other organs (p > 0.05). CONCLUSIONS: Compared with deep hypothermic circulatory arrest, moderate hypothermic circulatory arrest is a moderate technique that has similar advantages with regard to the levels of biomarkers of injury and capacity for protection against apoptosis in vital organs.

Structure-Activity and Structure-Conformation Relationships of Aryl Propionic Acid Inhibitors of the Kelch-like ECH-Associated Protein 1/Nuclear Factor Erythroid 2-Related Factor 2 (KEAP1/NRF2) Protein-Protein Interaction.

The KEAP1-NRF2-mediated cytoprotective response plays a key role in cellular homoeostasis. Insufficient NRF2 signaling during chronic oxidative stress may be associated with the pathophysiology of several diseases with an inflammatory component, and pathway activation through direct modulation of the KEAP1-NRF2 protein-protein interaction is being increasingly explored as a potential therapeutic strategy. Nevertheless, the physicochemical nature of the KEAP1-NRF2 interface suggests that achieving high affinity for a cell-penetrant druglike inhibitor might be challenging. We recently reported the discovery of a highly potent tool compound which was used to probe the biology associated with directly disrupting the interaction of NRF2 with the KEAP1 Kelch domain. We now present a detailed account of the medicinal chemistry campaign leading to this molecule, which included exploration and optimization of protein-ligand interactions in three energetic "hot spots" identified by fragment screening. In particular, we also discuss how consideration of ligand conformational stabilization was important to its development and present evidence for preorganization of the lead compound which may contribute to its high affinity and cellular activity.

Increased risk for the development of postoperative severe hypoxemia in obese women with acute type a aortic dissection.

BACKGROUND: The purpose of this study is to identify the risk factors for postoperative severe hypoxemia after surgery for acute type A aortic dissection. METHODS: This was a single-center retrospective study including 112 consecutive patients undergoing urgent aortic arch surgery for acute type A aortic dissection between December 2016 and April 2017 at Beijing Anzhen Hospital. RESULTS: Multivariate logistic regression analysis identified female (OR, 12.978; 95% CI, 3.332 to 50.546; p < 0.001) and increased body mass index (OR, 1.473; 95% CI, 1.213 to 1.789; p < 0.001) as independent predictors of postoperative severe hypoxemia in patients with acute type A aortic dissection. CONCLUSIONS: Obesity and female were independent risk factors for postoperative severe hypoxemia in patients with acute type A aortic dissection. More attention should be paid to preventing postoperative severe hypoxemia in obese women with acute type A aortic dissection.

Development of a High-Throughput Cul3-Keap1 Time-Resolved Fluorescence Resonance Energy Transfer (TR-FRET) Assay for Identifying Nrf2 Activators.

Nrf2, a master regulator of the phase II gene response to stress, is kept at low concentrations in the cell through binding to Keap1, an adaptor protein for the Cul3 ubiquitin ligase complex. To identify Nrf2 activators, two separate time-resolved fluorescence resonance energy transfer (TR-FRET) assays were developed to monitor the binding of Nrf2-Keap1 and Cul3-Keap1, respectively. The triterpenoid, 1-[2-cyano-3-,12-dioxooleana-1,9(11)-dien-28-oyl] imidazole (CDDO-Im) and its analogs, exhibited approximately 100-fold better potency in the Cul3-Keap1 assay than in the Nrf2-Keap1 assay, and this difference was more profound at 37 °C than at room temperature in the Nrf2-Keap1 assay, but this phenomenon was not observed in the Cul3-Keap1 assay. A full diversity screen of approximately 2,200,000 GSK compounds was run with the Cul3-Keap1 TR-FRET assay and multiple chemical series were identified and characterized.