Recently, MOEA/D (multi-objective evolutionary algorithm based on decomposition) has achieved great success in the field of evolutionary multi-objective optimization and has attracted a lot of attention. It decomposes a multi-objective optimization problem (MOP) into a set of scalar subproblems using uniformly distributed aggregation weight vectors and provides an excellent general algorithmic framework of evolutionary multi-objective optimization. Generally, the uniformity of weight vectors in MOEA/D can ensure the diversity of the Pareto optimal solutions, however, it cannot work as well when the target MOP has a complex Pareto front (PF; i.e., discontinuous PF or PF with sharp peak or low tail). To remedy this, we propose an improved MOEA/D with adaptive weight vector adjustment (MOEA/D-AWA). According to the analysis of the geometric relationship between the weight vectors and the optimal solutions under the Chebyshev decomposition scheme, a new weight vector initialization method and an adaptive weight vector adjustment strategy are introduced in MOEA/D-AWA. The weights are adjusted periodically so that the weights of subproblems can be redistributed adaptively to obtain better uniformity of solutions. Meanwhile, computing efforts devoted to subproblems with duplicate optimal solution can be saved. Moreover, an external elite population is introduced to help adding new subproblems into real sparse regions rather than pseudo sparse regions of the complex PF, that is, discontinuous regions of the PF. MOEA/D-AWA has been compared with four state of the art MOEAs, namely the original MOEA/D, Adaptive-MOEA/D, [Formula: see text]-MOEA/D, and NSGA-II on 10 widely used test problems, two newly constructed complex problems, and two many-objective problems. Experimental results indicate that MOEA/D-AWA outperforms the benchmark algorithms in terms of the IGD metric, particularly when the PF of the MOP is complex.

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Objective Aging is a major risk factor for numerous neurological disorders, and the mechanisms underlying brain aging remain elusive. Recent animal studies demonstrated a tight relationship between impairment of the glymphatic pathway, meningeal lymphatic vessels, and aging. However, the relationship in the human brain remains uncertain. Methods In this observational cohort study, patients underwent magnetic resonance imaging before and at multiple time points after intrathecal administration of a contrast agent. Head T1‐weighted imaging was performed to assess the function of the glymphatic pathway and head high‐resolution T2–fluid attenuated inversion recovery imaging to visualize putative meningeal lymphatic vessels (pMLVs). We measured the signal unit ratio (SUR) of 6 locations in the glymphatic pathway and pMLVs, defined the percentage change in SUR from baseline to 39 hours as the clearance of the glymphatic pathway and pMLVs, and then analyzed their relationships with aging. Results In all patients (N = 35), the SUR of the glymphatic pathway and pMLVs changed significantly after intrathecal injection of the contrast agent. The clearance of both the glymphatic pathway and pMLVs was related to aging (all p < 0.05). The clearance of pMLVs was significantly related to the clearance of the glymphatic pathway (all p < 0.05), and the clearance of the glymphatic pathway was significantly faster in patients with early filling of pMLVs than those with late filling (all p < 0.05). Interpretation We revealed that both the glymphatic pathway and pMLVs might be impaired in the aging human brain through the novel, clinically available method to simultaneously visualize their clearance. Our findings also support that in humans, pMLVs are the downstream of the glymphatic pathway. Ann Neurol 2020;87:357–369

Giant coronary artery aneurysm is a rare entity that is commonly caused by congenital malformation and combined with other cardiac anomalies. An optimal surgical operation should be based on the specific cardiac anomaly of the individual patient.

Bone marrow mesenchymal stem cells (MSCs) have improved cardiac performance when administered after acute myocardial infarction (MI) in both large-animal models and in patients.1,2 However, the results from randomized controlled clinical trials have been less impressive; the authors of one meta-analysis concluded that left ventricular ejection fractions (LVEFs) increased by just 2.92% in response to cell therapy.

A pathogenetic role of OH in myocardial stunning has been inferred from the protective effects of OH scavengers and iron chelators. However, conclusive demonstration of the OH radical hypothesis of myocardial stunning requires direct verification of three major, but still unproven, assumptions: (1) OH is produced in the stunned myocardium in vivo; (2) antioxidant therapy inhibits OH production; and (3) such inhibition results in enhanced recovery of contractility (ie, OH is necessary for the development of myocardial stunning). Since phenylalanine (Phe) reacts with OH to form the hydroxylated products ortho-, meta-, and para-tyrosines (o-, m-, and p-tyr), we used aromatic hydroxylation of Phe to detect OH formation in the stunned myocardium. Open-chest dogs undergoing a 15-minute coronary occlusion followed by reperfusion received an intravenous infusion of Phe (54.3 mg/kg for 11.5 minutes beginning 90 seconds before reperfusion); these animals were given either no antioxidant therapy (group I, n=15), N-2-mercaptopropionyl glycine (MPG) (group II, n=11), or MPG combined with superoxide dismutase, catalase, and desferrioxamine (group III, n=12). In addition, group IV (nonischemic control group, n=6) received Phe but did not undergo coronary occlusion, whereas group V (ischemic control group, n=16) underwent a 15-minute occlusion but did not receive Phe or antioxidants. The plasma concentrations of tyrosines in the local venous effluent and in the arterial blood were measured with high-performance liquid chromatography. In group I, production of o-and m-tyr, which are specific markers of OH formation, began during coronary occlusion but increased dramatically immediately after reperfusion, peaking at 1 minute and continuing up to 10 minutes of reperfusion. In group II, the production of o-and m-tyr was markedly decreased throughout the first 10 minutes of reperfusion. In group III, the production of m-tyr was decreased to levels similar to those in group II, whereas the production of o-tyr was almost completely abolished. There was no appreciable production of o-or m-tyr in group IV. Recovery of contractile function (assessed as systolic wall thickening) was increased in group I vs group V. Recovery of function was further enhanced in group II, with only a slight additional improvement in group III. This study demonstrates that (1) -OH is produced in the stunned myocardium in vivo after brief regional ischemia, (2) antioxidants, such as MPG or MPG combined with superoxide dismutase, catalase, and desferrioxamine, actually inhibit OH activity in vivo, (3) this inhibition results in attenuation of myocardial stunning, (4) there is an inverse relation between the magnitude of the inhibition of OH activity soon after reflow and the severity of the subsequent contractile dysfunction, and (5) Phe, which itself acts as an OH scavenger, attenuates postischemic dysfunction. These results provide direct evidence that OH is an important mediator of myocardial stunning and suggest that aromatic hydroxylation of Phe may be a u...

Objectives Body mass index (BMI) is commonly used in obesity classification as a surrogate measure and obesity is associated with a cluster of risk factors for cardiovascular disease. The aim of this study was to investigate BMI on short-term outcomes after cardiac surgery. Design A retrospective cohort study. Setting University teaching hospital, two centers. Participants The study consisted of 4,740 patients who underwent cardiac surgery of two hospitals from July 1, 2001 to June 30, 2013 in one hospital and from September 1, 2003 to August 31, 2014 in another hospital were included in this study. Interventions No changes to standard practice were required. Measurements and Main Results They were assigned into six BMI groups as follows: Underweight BMI < 18.5 kg/m2), Normal weight (18.5 ≤ BMI < 25 kg/m2), Overweight (25 ≤ BMI < 30 kg/m2), Class I (30 ≤ BMI < 35 kg/m2), Class II (35 ≤ BMI < 40 kg/m2) and Class III obese (BMI ≥ 40 kg/m2). Short-term major postoperative complications (post-operative stroke, cardiac arrest, new atrial fibrillation/flutter, permanent rhythm device insertion, deep sternal infection, sepsis, prolonged ventilation, pneumonia, renal dialysis, renal failure, ICU readmission, total ICU hours and readmission in 30 days) and mortalities (in-hospital mortality, 30-day mortality, operative mortality) were compared among various BMI groups after cardiac surgery. Age, gender, surgery type, family history of CAD, diabetes, hypertension, heart failure and lipid lowering medication were the risk factors for early outcomes. Multiple logistic regression analysis indicated that being Underweight or Class III obese may present with significant differences of some short-term outcomes, including deep sternal infection, prolonged ventilation, new atrial fibrillation/flutter and renal failure. However, being Overweight or Class I obese has a positive impact on discharge mortality and operative mortality. Conclusions The results of this study demonstrated that extreme obesity and underweight were significantly associated with early major adverse clinical outcomes. However, there was an “obese paradox” in short-term mortality after cardiac surgery.

BACKGROUND AND PURPOSE:The demonstration of prominent medullary veins in the deep white matter ipsilateral to acute ischemic stroke has been shown to predict poor clinical outcome. We have investigated the prognostic implications of prominent medullary veins in patients with subacute stroke who present outside the therapeutic window for revascularization therapy.