Lyso-PAF, a biologically inactive phospholipid, contributes to RAF1 activation.

Phospholipase A2, group VII (PLA2G7) is widely recognized as a secreted, lipoprotein-associated PLA2 in plasma that converts phospholipid platelet-activating factor (PAF) to a biologically inactive product Lyso-PAF during inflammatory response. We report that intracellular PLA2G7 is selectively important for cell proliferation and tumor growth potential of melanoma cells expressing mutant NRAS, but not cells expressing BRAF V600E. Mechanistically, PLA2G7 signals through its product Lyso-PAF to contribute to RAF1 activation by mutant NRAS, which is bypassed by BRAF V600E. Intracellular Lyso-PAF promotes p21-activated kinase 2 (PAK2) activation by binding to its catalytic domain and altering ATP kinetics, while PAK2 significantly contributes to S338-phosphorylation of RAF1 in addition to PAK1. Furthermore, the PLA2G7-PAK2 axis is also required for full activation of RAF1 in cells stimulated by epidermal growth factor (EGF) or cancer cells expressing mutant KRAS. Thus, PLA2G7 and Lyso-PAF exhibit intracellular signaling functions as key elements of RAS-RAF1 signaling.

Trans-vaccenic acid reprograms CD8+ T cells and anti-tumour immunity.

Diet-derived nutrients are inextricably linked to human physiology by providing energy and biosynthetic building blocks and by functioning as regulatory molecules. However, the mechanisms by which circulating nutrients in the human body influence specific physiological processes remain largely unknown. Here we use a blood nutrient compound library-based screening approach to demonstrate that dietary trans-vaccenic acid (TVA) directly promotes effector CD8+ T cell function and anti-tumour immunity in vivo. TVA is the predominant form of trans-fatty acids enriched in human milk, but the human body cannot produce TVA endogenously1. Circulating TVA in humans is mainly from ruminant-derived foods including beef, lamb and dairy products such as milk and butter2,3, but only around 19% or 12% of dietary TVA is converted to rumenic acid by humans or mice, respectively4,5. Mechanistically, TVA inactivates the cell-surface receptor GPR43, an immunomodulatory G protein-coupled receptor activated by its short-chain fatty acid ligands6-8. TVA thus antagonizes the short-chain fatty acid agonists of GPR43, leading to activation of the cAMP-PKA-CREB axis for enhanced CD8+ T cell function. These findings reveal that diet-derived TVA represents a mechanism for host-extrinsic reprogramming of CD8+ T cells as opposed to the intrahost gut microbiota-derived short-chain fatty acids. TVA thus has translational potential for the treatment of tumours.

Lysine acetylation restricts mutant IDH2 activity to optimize transformation in AML cells.

Mutant isocitrate dehydrogenase (IDH) 1 and 2 play a pathogenic role in cancers, including acute myeloid leukemia (AML), by producing oncometabolite 2-hydroxyglutarate (2-HG). We recently reported that tyrosine phosphorylation activates IDH1 R132H mutant in AML cells. Here, we show that mutant IDH2 (mIDH2) R140Q commonly has K413 acetylation, which negatively regulates mIDH2 activity in human AML cells by attenuating dimerization and blocking binding of substrate (α-ketoglutarate) and cofactor (NADPH). Mechanistically, K413 acetylation of mitochondrial mIDH2 is achieved through a series of hierarchical phosphorylation events mediated by tyrosine kinase FLT3, which phosphorylates mIDH2 to recruit upstream mitochondrial acetyltransferase ACAT1 and simultaneously activates ACAT1 and inhibits upstream mitochondrial deacetylase SIRT3 through tyrosine phosphorylation. Moreover, we found that the intrinsic enzyme activity of mIDH2 is much higher than mIDH1, thus the inhibitory K413 acetylation optimizes leukemogenic ability of mIDH2 in AML cells by both producing sufficient 2-HG for transformation and avoiding cytotoxic accumulation of intracellular 2-HG.

γ-6-Phosphogluconolactone, a Byproduct of the Oxidative Pentose Phosphate Pathway, Contributes to AMPK Activation through Inhibition of PP2A.

The oxidative pentose phosphate pathway (oxiPPP) contributes to cell metabolism through not only the production of metabolic intermediates and reductive NADPH but also inhibition of LKB1-AMPK signaling by ribulose-5-phosphate (Ru-5-P), the product of the third oxiPPP enzyme 6-phosphogluconate dehydrogenase (6PGD). However, we found that knockdown of glucose-6-phosphate dehydrogenase (G6PD), the first oxiPPP enzyme, did not affect AMPK activation despite decreased Ru-5-P and subsequent LKB1 activation, due to enhanced activity of PP2A, the upstream phosphatase of AMPK. In contrast, knockdown of 6PGD or 6-phosphogluconolactonase (PGLS), the second oxiPPP enzyme, reduced PP2A activity. Mechanistically, knockdown of G6PD or PGLS decreased or increased 6-phosphogluconolactone level, respectively, which enhanced the inhibitory phosphorylation of PP2A by Src. Furthermore, γ-6-phosphogluconolactone, an oxiPPP byproduct with unknown function generated through intramolecular rearrangement of δ-6-phosphogluconolactone, the only substrate of PGLS, bound to Src and enhanced PP2A recruitment. Together, oxiPPP regulates AMPK homeostasis by balancing the opposing LKB1 and PP2A.

Joint effects of sleep disturbance and renal function impairment on incident new-onset severe metabolic dysfunction-associated steatotic liver disease.

AIM: To elucidate the effects of sleep parameters and renal function on the risk of developing new-onset severe metabolic dysfunction-associated steatotic liver disease (MASLD). MATERIALS AND METHODS: The primary analysis involved a cohort of 305 257 participants. Multivariable Cox models were employed to calculate hazard ratios and 95% confidence intervals. Traditional mediation and two-step Mendelian randomization (MR) analyses were conducted to assess the associations and mediating roles of renal function indicators between sleep and new-onset severe MASLD. RESULTS: Poor sleep score and renal function biomarker score (RFS) were associated with an increased risk of new-onset severe MASLD (all ptrend <0.001). Participants with poor sleep patterns and the highest RFS had a 5.45-fold higher risk of new-onset severe MASLD, compared to those with healthy sleep patterns and the lowest RFS (p < 0.001). The RFS could explain 10.08% of the correlations between poor sleep score and risk of new-onset severe MASLD. Additionally, MR analyses supported a causal link between insomnia and new-onset severe MASLD and revealed a mediating role of chronic kidney disease in the connection between insomnia and new-onset severe MASLD risk. CONCLUSIONS: This study highlights the independent and combined associations of sleep parameters and renal function indicators with new-onset severe MASLD, underscoring the bidirectional communication of the liver-kidney axis and providing modifiable strategies for preventing MASLD.

Tetrameric Acetyl-CoA Acetyltransferase 1 Is Important for Tumor Growth.

Mitochondrial acetyl-CoA acetyltransferase 1 (ACAT1) regulates pyruvate dehydrogenase complex (PDC) by acetylating pyruvate dehydrogenase (PDH) and PDH phosphatase. How ACAT1 is "hijacked" to contribute to the Warburg effect in human cancer remains unclear. We found that active, tetrameric ACAT1 is commonly upregulated in cells stimulated by EGF and in diverse human cancer cells, where ACAT1 tetramers, but not monomers, are phosphorylated and stabilized by enhanced Y407 phosphorylation. Moreover, we identified arecoline hydrobromide (AH) as a covalent ACAT1 inhibitor that binds to and disrupts only ACAT1 tetramers. The resultant AH-bound ACAT1 monomers cannot reform tetramers. Inhibition of tetrameric ACAT1 by abolishing Y407 phosphorylation or AH treatment results in decreased ACAT1 activity, leading to increased PDC flux and oxidative phosphorylation with attenuated cancer cell proliferation and tumor growth. These findings provide a mechanistic understanding of how oncogenic events signal through distinct acetyltransferases to regulate cancer metabolism and suggest ACAT1 as an anti-cancer target.

Residual biliary intraepithelial neoplasia without malignant transformation at resection margin for perihilar cholangiocarcinoma does not require expanded resection: a dual center retrospective study.

BACKGROUND: Additional resection for invasive cancer at perihilar cholangiocarcinoma (pCCA) resection margins has become a consensus. However, controversy still exists regarding whether additional resection is necessary for residual biliary intraepithelial neoplasia (BilIN). METHOD: Consecutive patients with pCCA from two hospitals were enrolled. The incidence and pattern of resection margin BilIN were summarized. Prognosis between patients with negative margins (R0) and BilIN margins were analyzed. Cox regression with a forest plot was used to identify independent risk factors associated with overall survival (OS) and recurrence-free survival (RFS). Subgroup analysis was performed based on BilIN features and tumor characteristics. RESULTS: 306 pCCA patients receiving curative resection were included. 255 had R0 margins and 51 had BilIN margins. There was no significant difference in OS (P = 0.264) or RFS (P = 0.149) between the two group. Specifically, 19 patients with BilIN at distal bile ducts and 32 at proximal bile ducts. 42 patients showed low-grade BilIN, and 9 showed high-grade. Further analysis revealed no significant difference in long-term survival between different locations (P = 0.354), or between different grades (P = 0.772). Portal vein invasion, poor differentiation and lymph node metastasis were considered independent risk factors for OS and RFS, while BilIN was not. Subgroup analysis showed no significant difference in long-term survival between the lymph node metastasis subgroup, or between the portal vein invasion subgroup. CONCLUSION: For pCCA patients underwent curative resection, residual BilIN at resection margin is acceptable. Additional resection is not necessary for such patients to achieve absolute R0 margin.

Vascular reconstruction provides short-term and long-term survival benefits for patients with hilar cholangiocarcinoma: A retrospective, multicenter study.

BACKGROUND: In patients with hilar cholangiocarcinoma (HCCA), radical resection can be achieved by resection and reconstruction of the vasculature. However, whether vascular reconstruction (VR) improves long-term and short-term prognosis has not been demonstrated comprehensively. METHODS: This was a retrospective multicenter study of patients who received surgery for HCCA with or without VR. Variables associated with overall survival (OS) and recurrence-free survival (RFS) were identified based on Cox regression. Kaplan-Meier curves were used to explore the impact of VR. Restricted mean survival time (RMST) was used for comparisons of short-term survival between the groups. Patients' intraoperative and postoperative characteristics were compared. RESULTS: Totally 447 patients were enrolled. We divided these patients into 3 groups: VR with radical resections (n = 84); non-VR radical resections (n = 309) and non-radical resection (we pooled VR-nonradical and non-VR nonradical together, n = 54). Cox regression revealed that carbohydrate antigen 242 (CA242), vascular invasion, lymph node metastasis and poor differentiation were independent risk factors for OS and RFS. There was no significant difference of RMST between the VR and non-VR radical groups within 12 months after surgery (10.18 vs. 10.76 mon, P = 0.179), although the 5-year OS (P < 0.001) and RFS (P < 0.001) were worse in the VR radical group. The incidences of most complications were not significantly different, but those of bile leakage (P < 0.001) and postoperative infection (P = 0.009) were higher in the VR radical group than in the non-VR radical group. Additionally, the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) up to 7 days after surgery tended to decrease in all groups. There was no significant difference in the incidence of postoperative liver failure between the VR and non-VR radical groups. CONCLUSIONS: Radical resection can be achieved with VR to improve the survival rate without worsening short-term survival compared with resection with non-VR. After adequate assessment of the patient's general condition, VR can be considered in the resection.

Polycyclic aromatic compounds (PACs) in industrial soils from northwestern of China: occurrence, distribution, exposure risk, and implications on risk-based controls.

Some Polycyclic Aromatic Compounds (PACs) such as nitrated-PAHs (NPAHs), oxygenated-PAHs (OPAHs) and methyl-PAHs (MPAHs) have attracted significant concern due to derivatives have greater potential to be more toxic at low environmental concentrations compared to their PPAHs, particularly in petrochemical industrial region and its surrounding areas surface soils in China. Hence, this article provides an insight into the fate, sources, impacts, and relevance to the external environment of PAH-derivatives based on important emissions source. Moreover, prospective health risk due to their exposure has also been discussed. In this study, the concentration (10-3 ng/g) of Æ©18PPAHs, Æ©11MPAHs, Æ©12NPAHs, and Æ©4OPAHs in the park were 9.67 ± 1.40, 3.24 ± 0.54, 0.03 ± 0.02 and 0.19 ± 0.65, respectively, which were 4.47, 3.89, 2.04 and 1.17 times than of them surrounding the region. A decreasing trend of the low molecular weight (2-4Rings) contribution to the total amount of PAHs, while the fraction of high molecular weight (5-6Rings) species showed the opposite trend. According to the principal component analysis (PCA) and diagnostic ratios indicated PAHs in the soil samples have mixed sources from industrial activities, solid fuel combustion, and heavy traffic. Despite the high concentrations of MPAHs and OPAHs, the toxicity equivalency quotients (TEQs) of them were not calculated due to the lack of toxic equivalent factors (TEF), thus current studies on PAH and derivatives could have underestimated their exposure risks. The quality and sustainable management of soils are crucial for human health and sustainable development, while there is lack of public awareness of the severe issue of soil pollution. It is recommended to conduct more intensive monitoring and regional assessments in the future.

Development of a Dual-Factor Activatable Covalent Targeted Photoacoustic Imaging Probe for Tumor Imaging.

Photoacoustic imaging (PAI) is an emerging modality in biomedical imaging with superior imaging depth and specificity. However, PAI still has significant limitations, such as the background noise from endogenous chromophores. To overcome these limitations, we developed a covalent activity-based PAI probe, NOx-JS013, targeting NCEH1. NCEH1, a highly expressed and activated serine hydrolase in aggressive cancers, has the potential to be employed for the diagnosis of cancers. We show that NOx-JS013 labels active NCEH1 in live cells with high selectivity relative to other serine hydrolases. NOx-JS013 also presents its efficacy as a hypoxia-responsive imaging probe in live cells. Finally, NOx-JS013 successfully visualizes aggressive prostate cancer tumors in mouse models of PC3, while being negligibly detected in tumors of non-aggressive LNCaP mouse models. These findings show that NOx-JS013 has the potential to be used to develop precision PAI reagents for detecting metastatic progression in various cancers.

Astragaloside IV suppresses the migration and EMT progression of cervical cancer cells by inhibiting macrophage M2 polarization through TGFß/Smad2/3 signaling.

Cervical cancer (CC) is a gynecological malignant tumor worldwide. Astragaloside IV (AS-IV) has been found to exert antitumor effects on CC. In addition, M2-polarized macrophages, known as tumor-associated macrophages (TAMs), play an important role in promoting cancer cell growth and angiogenesis. Thus, we explored the association between the antitumor effect of AS-IV and macrophage polarization in CC. Flow cytometry, ELISA, and RT‒qPCR assays were applied to detect the levels of CD163, IL-10, TGFß, and CD206 in M2 macrophages with or without AS-IV treatment. In addition, conditioned medium (CM) was collected from these M2 macrophages, and CC cells were then cultured in various CMs. Wound healing and transwell assays were used to assess the migratory ability of CC cells. In this study, we found that AS-IV significantly inhibited M2 polarization of macrophages, as shown by decreased CD163, IL-10, TGFß, and CD206 expression. In addition, compared with CM from M2 macrophages, CM from AS-IV-treated M2 macrophages notably inhibited angiogenesis, migration, and epithelial-mesenchymal transition (EMT) in CC cells. Furthermore, compared with CM from M2 macrophages, CM from AS-IV-treated M2 macrophages markedly reduced p-Smad2 and p-Smad3 protein expression in CC cells, and these changes were reversed by TGF-ß treatment. Collectively, suppression of M2-like polarization of macrophages by AS-IV could prevent the migration and EMT of CC cells by inactivating TGF-ß/Smad2/3 signaling. These findings might provide some theoretical support for exploring novel treatments for CC.

Genetic variants associated with expression of TCF19 contribute to the risk of head and neck cancer in Chinese population.

BACKGROUND: Squamous cell carcinoma of the head and neck (SCCHN) is one of the most common cancers worldwide and includes cancers arising from the oral cavity, pharynx and larynx. Genome-wide association studies have found several genetic variants related to the risk of SCCHN; however, they could only explain a small fraction of the heritability. Thus, more susceptibility loci associated with SCCHN need to be identified. METHODS: An association study was conducted by genotyping 555 patients with SCCHN and 1367 controls in a Chinese population. Single-variant association analysis was conducted on 63 373 SNPs, and the promising variants were then confirmed by a two-stage validation with 1875 SCCHN cases and 4637 controls. Bioinformatics analysis and functional assays were applied to uncover the potential pathogenic mechanism of the promising variants and genes associated with SCCHN. RESULTS: We first identified three novel genetic variants significantly associated with the risk of SCCHN (p=7.45×10-7 for rs2517611 at 6p22.1, p=1.76×10-9 for rs2524182 at 6p21.33 and p=2.17×10-10 for rs3131018 at 6p21.33). Further analysis and biochemical assays showed that rs3094187, which was in a region in high linkage disequilibrium with rs3131018, could modify TCF19 expression by regulating the binding affinity of the transcription factor SREBF1 to the promoter of TCF19. In addition, experiments revealed that the inhibition of TCF19 may affect several important pathways involved in tumourigenesis and attenuate the cell proliferation and migration of SCCHN. CONCLUSION: These findings offer important evidence that functional genetic variants could contribute to development of SCCHN and that TCF19 may function as a putative susceptibility gene for SCCHN.

Gastroduodenal artery disconnection during liver transplantation decreases non-anastomotic stricture incidence.

BACKGROUND: The hepatic artery is the only blood source nourishing the biliary duct and associated with biliary complication after liver transplantation (LT). Gastroduodenal artery (GDA) disconnection increased proper hepatic artery flow. Whether this procedure attenuates biliary non-anastomotic stricture (NAS) is not clear. METHODS: A total of 241 patients with LT were retrospectively analyzed. The patients were divided into the GDA disconnection (GDA-) and GDA preservation (GDA+) groups. Propensity score matching (PSM) was administrated to reduce bias. Logistic regression was conducted to analyze risk factors for biliary NAS before and after PSM. Postoperative complications were compared. Kaplan-Meier survival analysis and log-rank tests were performed to compare overall survival. RESULTS: In all, 99 patients (41.1%) underwent GDA disconnection, and 49 (20.3%) developed NAS. Multivariate logistic regression revealed that GDA preservation (OR = 2.24, 95% CI: 1.11-4.53; P = 0.025) and model for end-stage liver disease (MELD) score > 15 (OR = 2.14, 95% CI: 1.12-4.11; P = 0.022) were risk factors for biliary NAS. PSM provided 66 pairs using 1:2 matching method, including 66 GDA disconnection and 99 GDA preservation patients. Multivariate logistic regression after PSM also showed that GDA preservation (OR = 3.15, 95% CI: 1.26-7.89; P = 0.014) and MELD score > 15 (OR = 2.41, 95% CI: 1.08-5.36; P = 0.031) were risk factors for NAS. When comparing complications between the two groups, GDA preservation was associated with a higher incidence of biliary NAS before and after PSM (P = 0.031 and 0.017, respectively). In contrast, other complications including early allograft dysfunction (P = 0.620), small-for-size graft syndrome (P = 0.441), abdominal hemorrhage (P = 1.000), major complications (Clavien-Dindo grade ≥ 3, P = 0.318), and overall survival (P = 0.088) were not significantly different between the two groups. CONCLUSIONS: GDA disconnection during LT ameliorates biliary NAS incidence and may be recommended for application in clinical practice.

Functional characterization and clinical significance of super-enhancers in lung adenocarcinoma.

Super-enhancers (SEs) are important transcriptional regulators in tumorigenesis; however, the functional characterization and clinical significance of SEs in lung adenocarcinoma (LUAD) remain unclear. By using H3K27ac ChIP-seq data of two LUAD cell lines and eight lung tissues, we detected 1045 cancer-specific and 5032 normal-specific SEs. Compared to normal-specific SEs, cancer-specific SEs have different regulatory mechanisms where associated target genes were enriched in critical tumor-related pathways and tended to be regulated by transcription factors of Fos Proto-Oncogene, AP-1 Transcription Factor Subunit and Jun Proto-Oncogene, AP-1 Transcription Factor Subunit families. By using expression data of 513 LUAD and 57 adjacent samples from The Cancer Genome Atlas and 80 tumor-normal paired LUAD samples from the Nanjing Lung Cancer Cohort study, we performed differential expression analysis of target genes for SEs and defined 243 crucial SEs. Unsupervised clustering of crucial SEs revealed two subtypes with different levels of genomic aberrations (i.e., mutation and copy number alteration) and clinical outcomes (progression-free interval: p = 0.030; disease-free interval: p = 0.047). In addition, patients with adverse clinical outcomes were more sensitive to three small molecule inhibitors (bortezomib, doxorubicin, and etoposide), and their targets (PSMB5 and TOP2A) also have elevated expression levels among these patients. Taken together, our findings provided a comprehensive characterization of SEs in LUAD and emphasized their clinical significance in LUAD therapy.

Actively targeted delivery of SN38 by ultrafine iron oxide nanoparticle for treating pancreatic cancer.

Pancreatic cancer remains one of the most lethal cancers largely due to the inefficient delivery of therapeutics. Nanomaterials have been extensively investigated as drug delivery platforms, showing improved drug pharmacodynamics and pharmacokinetics. However, their applications in pancreatic cancer have not yet been successful due to limited tumor delivery caused by dense tumor stroma and distorted tumor vasculatures. Meanwhile, smaller-sized nanomaterials have shown improved tumor delivery and retention in various tumors, including pancreatic tumors, suggesting their potential in enhancing drug delivery. An ultrafine iron oxide nanoparticle (uIONP) was used to encapsulate 7-ethyl-10-hydroxyl camptothecin (SN38), the water-insoluble active metabolite of pancreatic cancer chemotherapy drug irinotecan. Insulin-like growth factor 1 (IGF-1) was conjugated to uIONP as a ligand for targeting pancreatic cancer cells overexpressing IGF-1 receptor (IGF1R). The SN38 loading and release profile were characterized. The pancreatic cancer cell targeting using IGF1-uIONP/SN38 and subsequently induced cell apoptosis were also investigated. IGF1-uIONP/SN38 demonstrated a stable drug loading in physiological pH with the loading efficiency of 68.2 ± 3.5% (SN38/Fe, wt%) and < 7% release for 24 h. In tumor-interstitial- and lysosomal-mimicking pH (6.5 and 5.5), 52.2 and 91.3% of encapsulated SN38 were released over 24 h. The IGF1-uIONP/SN38 exhibited specific receptor-mediated cell targeting and cytotoxicity Ato MiaPaCa-2 and Panc02 pancreatic cancer cells with IC50 of 11.8 ± 2.3 and 20.8 ± 3.5 nM, respectively, but not to HEK293 human embryonic kidney cells. IGF1-uIONP significantly improved the targeted SN38 delivery to pancreatic cancer cells, holding the potential for in vivo theranostic applications.

Lysine acetylation activates 6-phosphogluconate dehydrogenase to promote tumor growth.

Although the oxidative pentose phosphate pathway is important for tumor growth, how 6-phosphogluconate dehydrogenase (6PGD) in this pathway is upregulated in human cancers is unknown. We found that 6PGD is commonly activated in EGF-stimulated cells and human cancer cells by lysine acetylation. Acetylation at K76 and K294 of 6PGD promotes NADP(+) binding to 6PGD and formation of active 6PGD dimers, respectively. Moreover, we identified DLAT and ACAT2 as upstream acetyltransferases of K76 and K294, respectively, and HDAC4 as the deacetylase of both sites. Expressing acetyl-deficient mutants of 6PGD in cancer cells significantly attenuated cell proliferation and tumor growth. This is due in part to reduced levels of 6PGD products ribulose-5-phosphate and NADPH, which led to reduced RNA and lipid biosynthesis as well as elevated ROS. Furthermore, 6PGD activity is upregulated with increased lysine acetylation in primary leukemia cells from human patients, providing mechanistic insights into 6PGD upregulation in cancer cells.

Lipid metabolism within the bone micro-environment is closely associated with bone metabolism in physiological and pathophysiological stages.

Recent advances in society have resulted in the emergence of both hyperlipidemia and obesity as life-threatening conditions in people with implications for various types of diseases, such as cardiovascular diseases and cancer. This is further complicated by a global rise in the aging population, especially menopausal women, who mostly suffer from overweight and bone loss simultaneously. Interestingly, clinical observations in these women suggest that osteoarthritis may be linked to a higher body mass index (BMI), which has led many to believe that there may be some degree of bone dysfunction associated with conditions such as obesity. It is also common practice in many outpatient settings to encourage patients to control their BMI and lose weight in an attempt to mitigate mechanical stress and thus reduce bone pain and joint dysfunction. Together, studies show that bone is not only a mechanical organ but also a critical component of metabolism, and various endocrine functions, such as calcium metabolism. Numerous studies have demonstrated a relationship between metabolic dysfunction in bone and abnormal lipid metabolism. Previous studies have also regarded obesity as a metabolic disorder. However, the relationship between lipid metabolism and bone metabolism has not been fully elucidated. In this narrative review, the data describing the close relationship between bone and lipid metabolism was summarized and the impact on both the normal physiology and pathophysiology of these tissues was discussed at both the molecular and cellular levels.

CLSQL: Improved Q-Learning Algorithm Based on Continuous Local Search Policy for Mobile Robot Path Planning.

How to generate the path planning of mobile robots quickly is a problem in the field of robotics. The Q-learning(QL) algorithm has recently become increasingly used in the field of mobile robot path planning. However, its selection policy is blind in most cases in the early search process, which slows down the convergence of optimal solutions, especially in a complex environment. Therefore, in this paper, we propose a continuous local search Q-Learning (CLSQL) algorithm to solve these problems and ensure the quality of the planned path. First, the global environment is gradually divided into independent local environments. Then, the intermediate points are searched in each local environment with prior knowledge. After that, the search between each intermediate point is realized to reach the destination point. At last, by comparing other RL-based algorithms, the proposed method improves the convergence speed and computation time while ensuring the optimal path.

Fractal Analysis: Prognostic Value of Left Ventricular Trabecular Complexity Cardiovascular MRI in Participants with Hypertrophic Cardiomyopathy.

Background The prognostic value of myocardial trabecular complexity in patients with hypertrophic cardiomyopathy (HCM) is unknown. Purpose To explore the prognostic value of myocardial trabecular complexity using fractal analysis in participants with HCM. Materials and Methods The authors prospectively enrolled participants with HCM who underwent 3.0-T cardiovascular MRI from August 2011 to October 2017. The authors also enrolled 100 age- and sex-matched healthy participants to form a comparison group. Trabeculae were quantified with fractal analysis of cine slices to estimate the fractal dimension (FD). Participants with HCM were divided into normal and high FD groups according to the upper limit of normal reference value from the healthy group. The primary end point was defined as all-cause mortality and aborted sudden cardiac death. The secondary end point was the composite of the primary end point and readmission to the hospital owing to heart failure. Internal validation was performed using the bootstrapping method. Results A total of 378 participants with HCM (median age, 50 years; age range, 40-61 years; 207 men) and 100 healthy participants (median age, 46 years; age range, 36-59 years; 55 women) were included in this study. During the median follow-up of 33 months ± 18 (standard deviation), the increased maximal apical FD (≥1.325) had a higher risk of the primary and secondary end points than those with a normal FD (<1.325) (P = .01 and P = .04, respectively). Furthermore, Cox analysis revealed that left ventricular maximal apical FD (hazard ratio range, 1.001-1.008; all P < .05) provided significant prognostic value to predict the primary and secondary end points after adjustment for the European Society of Cardiology predictors and late gadolinium enhancement. Internal validation showed that left ventricular maximal apical FD retained a good performance in predicting the primary end points with an area under the curve of 0.70 ± 0.03. Conclusion Left ventricular apical fractal dimension, which reflects myocardial trabecular complexity, was an independent predictor of the primary and secondary end points in patients with hypertrophic cardiomyopathy. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Captur and Moon in this issue.

Prognostic value of myocardial extracellular volume fraction evaluation based on cardiac magnetic resonance T1 mapping with T1 long and short in hypertrophic cardiomyopathy.

OBJECTIVE: To investigate the prognostic significance of T1 mapping using T1 long and short in hypertrophic cardiomyopathy (HCM) patients. METHODS: A total of 263 consecutive patients with HCM referred for cardiovascular magnetic resonance (CMR) imaging were enrolled in this study. The imaging protocol consisted of cine, late gadolinium enhancement (LGE), and T1 mapping with T1 long and short. All patients were followed up prospectively. Outcome events were divided into the primary and secondary endpoint events. Primary endpoint events included cardiac death, heart transplant, aborted sudden death, and cardiopulmonary resuscitation after syncope. The secondary endpoint event was defined as unplanned rehospitalization for heart failure. RESULT: The average follow-up duration was 28.3 ± 12.1 (range: 1-78) months. In all, 17 patients (7.0%) experienced a primary endpoint including 13 cardiovascular deaths, three aborted sudden deaths, and one resuscitation after syncope, and 34 patients experienced a secondary endpoint. Patients with primary endpoints showed a trend towards more extensive LGE (p < 0.001), significantly higher ECV (p < 0.001), and native T1 (p = 0.028) than those without events. In multivariate Cox regression analysis, ECV was independently associated with primary and secondary endpoints (p < 0.001 and p = 0.047, respectively). For every 3% increase, ECV portended a 1.374-fold increase risk of a primary endpoint occurring (p < 0.001). In the Kaplan-Meier survival analysis, the incidence of primary and secondary endpoint events was significantly higher in HCM with increased ECV (p < 0.001 and p = 0.009, respectively). CONCLUSION: In patients with HCM, ECV is a strong imaging marker for predicting adverse outcome. KEY POINTS: • ECV is a potent imaging index which has a strong correlation with LVEF and LVEDVI and can evaluate myocardial tissue structure and function. • ECV and LGE can provide a prognostic value in patients with hypertrophic cardiomyopathy. • ECV has stronger predictive effectiveness than LGE; even in the subgroup with LGE, ECV shows independent predictive significance for adverse events.