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Background: Acute myocardial infarction (AMI) is a leading cause of death and disability. Diabetes is an important risk factor and a common comorbidity in AMI patients. The higher mortality risk of diabetes-AMI relative to nondiabetes-AMI indicates a need for specific treatment to improve clinical outcome. However, the global metabolic dysregulation of AMI complicated with diabetes is still unclear. We aim to systematically interrogate changes in the metabolic microenvironment immediate to AMI episodes in the absence or presence of diabetes. Methods: In this work, quantitative metabolomics was used to investigate plasma metabolic differences between diabetes-AMI (n=59) and nondiabetes-AMI (n=59) patients. A diverse array of perturbed metabolic pathways involving carbohydrate metabolism, lipid metabolism, glycolysis, tricarboxylic acid cycle, and amino acid metabolism emerged. Results: In all, our omics-oriented approach defined a metabolic signature of afflicted mitochondrial function aggravated by concurrent diabetes in AMI patients. In particular, our analyses uncovered N-lactoyl-phenylalanine and lysophosphatidylcholines as key functional metabolites that skewed the metabolic picture of diabetes-AMI relative to nondiabetes-AMI. N-lactoyl-phenylalanine was strongly associated with metabolic indicators reflective of mitochondrial overload and negatively correlated with HbA1c (glycosylated hemoglobin, type A1C) specifically in hyperglycemic AMI, suggestive of its central role in glucose utilization and mitochondrial energy production instrumental to the clinical outcome of diabetes-AMI. Reductions in lysophosphatidylcholines, which were negatively correlated with blood glucose and inflammatory markers, might further compromise glucose expenditure and aggravate inflammation leading to poorer prognosis in diabetes-AMI. Conclusions: As circulating metabolite levels are amenable to therapeutic intervention, such shifts in metabolic signatures provide new clues and potential therapeutic targets specific to the treatment of diabetes-AMI.

Urotensin II (UII) is involved in the formation of atherosclerosis, but its role in the stability of atherosclerotic plaques is unknown. The purpose of this study was to observe the dynamic changes in plasma UII and analyze its relationship to the stability of atherosclerotic plaques. One hundred thirty-five consecutive patients with acute coronary syndrome (ACS) were enrolled. The plasma UII levels were measured immediately after admission and during three-month follow-up. A vulnerable plaque model was established using local transfection of a recombinant P53 adenovirus into plaques in rabbits fed with a high-cholesterol diet and subjected to balloon arterial injury. The levels of plasma UII were measured weekly. The changes in plasma UII during the formation of atherosclerotic plaques and before and after plaque transfection were observed. The morphology of the plaques and the expression, distribution, and quantitative expression of UII in the plaques also were observed. Our results showed that the levels of plasma UII in patients with ACS at admission were lower than levels observed at the three-month follow-up. UII dynamic changes and its correlation with plaque stabilities were further verified in rabbits with atherosclerotic vulnerable plaques. The UII levels in rabbits were significantly decreased immediately after the P53 gene transfection, which led to plaque instability and rupture. These results suggested that UII expression was down-regulated in ACS, which may be related to its ability to modulate mechanisms involved in plaque stability and instability.

Retinoic acid (RA) analogs have been used in the treatment of a variety of cancers; however, their application is limited due to serious therapy-related sequelae. In the present study, the effects of a novel RA analog, 4-amino-2-trifluoromethyl-phenyl retinate (ATPR), on the growth of gastric cancer cells were evaluated. Three gastric cancer cell lines, AGS, MKN-74 and SC-M1, were treated with either all‑trans retinoic acid (ATRA) or ATPR, and their growth and distribution in different cell cycle phases were assessed using an MTT assay and propidium iodide (PI) staining followed by flow cytometry. The binding affinity of ATPR to the retinoic acid receptors, retinoic acid receptor-α (RAR-α) and retinoid X receptor-α (RXR-α), was determined using ligand-binding assays. Activator protein-1 (AP-1) activity was measured using a luciferase reporter assay. Western blot analysis was used to determine cyclin E, Bcl-2 and Bax protein expression. ATPR preferentially bound RXR-α (0.04 nM) as compared with RAR-α (20.96 nM). Although both ATRA and ATPR inhibited the growth of AGS, MKN-74 and SC-M1 cells in a dose-dependent manner, a significantly greater inhibitory effect was observed with treatment with 5 and 500 µM ATPR for 3 days (P

To evaluate the safety and efficacy of antiplatelet therapy of ticagrelor on patients suffering from acute ST segment elevation myocardial infarction undergoing primary percutaneous coronary intervention.In the study, 96 patients suffering from acute ST segment elevation myocardial infarction onset within 12 h undergoing primary percutaneous coronary intervention from May to October in 2013 were randomly divided into ticagrelor group (n=48) and clopidogrel group (n=48) by using the method of random number table. Ticagrelor and clopidogrel antiplatelet treatment were used before and after operation. Their baseline data, coronary artery disease characteristics, platelet count, adenosine diphosphate(ADP)-induced platelet inhibition rate by thrombelastograph after 5 days of treatment, the major adverse cardiovascular events of the follow up for 6 months and bleeding complications were observed and compared in the two groups.The differences between the two groups of patients with their baseline data, the features of coronary artery lesions, platelet count before and after 5 days of treatment had no statistical significance (P0.05). ADP induced platelet inhibition rate [(80.2±10.7)%] after 5 days of treatment in ticagrelor group was significantly higher than that in clopidogrel group [(75.3±12.1)%, P0.05]. The two groups of patients were followed up for 6 months, 8 cases of major adverse cardiovascular events occurred in clopidogrel group, 2 cases of major adverse cardiovascular events occurred in ticagrelor group, and there was significant difference between the two groups (P0.05). The two groups (7 cases of 48 patients in ticagrelor group vs. 3 cases of 48 patients in clopidogrel group) had no statistically significant difference in bleeding complications (P0.05).Antiplatelet therapy of ticagrelor on patients suffering from acute ST segment elevation myocardial infarction undergoing emergency PCI has good efficacy and safety.

To explore the protective effect and possible mechanism of intensive lipid modulation on the perioperative period of patients with stable coronary artery disease undergoing noncardiac surgery.In the study, 60 patients with stable coronary artery disease undergoing elective noncardiac surgery were randomly divided into intensive lipid modulation group (n = 30) and conventional group (n = 30). In intensive lipid modulation group, the patients were given atorvastatin 40 mg every night before surgery, 80 mg 12 h before surgery, and 40 mg 2 h before surgery, and 40 mg every night after noncardiac surgery. In conventional group, the patients were given atorvastatin 20 mg every night before surgery and also after the surgery. The occurrence of perioperative major adverse cardiac events (including sudden cardiac death, acute myocardial infarction, unplanned revascularization) were compared in the two groups. Preoperative and 48 h postoperative changes of lipid levels and inflammatory markers were also compared in the two groups.In conventional group, one patient suffered myocardial infarction with acute anterior ST-segment elevation and was given emergency left anterior descending artery interventional reperfusion therapy, and 7 patients suffered asymptomatic myocardial infarction. In intensive lipid modulation group, one patient suffered asymptomatic myocardial infarction, and the incidence rate of perioperative acute myocardial infarction reduced significantly compared with conventional group (P0.05). There was no significant difference in preoperative and postoperative changes of lipid levels in the two groups (P0.05), and compared with conventional group, there was significantly lower levels of inflammatory markers in intensive lipid modulation group (P0.05).The intensive lipid modulation group significantly reduced the incidence of perioperative major adverse cardiac events especially asymptomatic myocardial infarction, and the inhibition of the inflammatory response may be one of the protective mechanisms, which still needs to be further confirmed by large multicenter randomized controlled clinical trials.

This paper analyses numerically the data on the large two-ribbon flare of 1996 March 24 obtained at Purple Mountain Observatory. The results show that filament activation plays an important role in the triggering of the flare, that both the emerging flux of opposite polarity and photospheric shearing motion near the filament footpoint are responsible for the filament eruption. The emerging flux causes changes in the background field and the shearing motion which twists the axial magnetic field inside the filament leads to an increase in the electric current, so the filament ceases to be in equilibrium and moves upwards. Lastly, the physical relation between the ascending motion of the filament and the eruption of the flare is analysed and discussed.

Relationship between the rising movement of the filaments, the evolutions of filament current systems and the flares on 13 May, 1981, 16 May, 1981, and 4 February, 1986, have been studied. We have obtained the following results: (1) The flare-filament current systems show great variety. For the flare of 13 May, 1981, the current system might be considered as a simple current loop. Calculations suggest that it was triggered by tearing-mode spontaneous reconnection caused by the magnetic twist within the filament. The 16 May flare, occurred in the same active region as the 13 May flare, and both eruptions were due to the evolution and the motion of the same filament, but the release of the magnetic energy of the 16 May flare may have taken place in the current sheet beneath the rising filament. This would mean that the flare of 16 May, 1981 result from current-sheet reconnection. Furthermore, the flare of 4 February, 1986 may be the result of the coalescence of two filament current loops. Thus a variety of flares might be explained by different magnetic reconnections caused by different filament rising movements and different filament current systems. (2) The resistive tearing instability could be regarded as the heating mechanism of the preflare phase (for the flare of 4 February, 1986) and sometimes may develop into the hot phase of the flare (for the flare of 13 May, 1981). (3) When we solve the momentum equation, different background fields of the active region should be taken for different active regions. For active region Hale 17644, the potential field can be taken as approximate description of the background field because there is no observed large-scale shear; but for active region 4711, which is strongly stressed, force-free field was chosen to describe the background field. Meantime, calculations show that for the flare of 4 February, 1986, only a force-free field which changes quickly with height could fit the observed rising movement of the filament.

A numerical calculation shows that newly emergent magnetic flux is an effective mechanism of driving and activating the dark filaments, through the interaction between the filament current and the background magnetic field. According to the strength of the flux, the filament may either oscilalte, rise, or twinkle. The emergence of a flux of the same polarity of sufficient strength will cause the filament to sink immediately.

We studied the 120 solar gamma-ray events observed by the gamma-ray spectrometer (GRS) on board the SMM satellite between 1980 March and 1983 June with particular emphasis on the basic properties of the active regions producing such events. Combined with observed data of Type-II and Type-IV metre wave radio bursts, we further discussed the physical mechanisms in solar flares. Our results show 1) that gamma-ray flares generally occur in morphologically and magnetically complicated regions; 2) that flares with gamma-ray lines (nuclear lines) are closely related to Type-II and Type-IV bursts; 3) that there are regions with multiple gamma-ray flares. These have particularly complicated structures, the δ-type magnetic configuration without exception and many other interesting features which should provide a clear observational basis for building a reasonable flare model; 4) that a deep study of the electric current in the active region and plasma instabilities involving the current is important for understanding the basic physical process of flares; and 6) that different flares may have different particle acceleration mechanisms at work.

We discuss the dispersion relation of local linear waves in a compressible and perfectly conducting gas possessing magnetic and gravitational fields in a slowly rotating frame of reference. Instead of the full energy equation and a gas law, a not necessarily adiabatic equation of state p = p ( ϱ ) is used to close the system of equations, — an arguably flexible way of treatment when we are not clear about the contributions by radiation and conductivity to the energy transport. We give a general dimensionless dispersion relation, (8). This reduces to (9) if the magnetic field B is zero; to (10) if, further, rotation φ is zero; to the relation for accoustic waves (11), if further the gravitational field G is zero. When B is not zero, we consider various cases with the propagation vector K always perpendicular to B: the relation now reduces to (13) if K is not perpendicular to φ; to (14) if, further, K is parallel to G; to (15) if φ =0; to the relation for last magneto-accoustic waves (16) if G=0. It reduces to (17) if K is perpendicular to G; to the fast magneto-accoustic waves (18), if, further, φ =0. It reduces to (19) if K is perpendicular to φ and to (20), if, further, K is parallel to G. Our study shows that, in general, there are no pure modes, only hybrids. In particular, a rotation gives rise to modes that are dependent on the latitude, which we call “physico-geometrical” waves. The present study is preliminary, and we may expect even more interesting results when we take into consideration the energy equation and the effects of radiation.