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Cytosine methylation (C meth) is a ubiquitous regulator of gene transcription. The maize gene ZmGRP3 is a notable marker for root initiation, but how its root-specific transcription is regulated is not understood. Here, bisulfite sequencing and a C meth sensitive Southern blot assay were used to show that the transcription of ZmGRP3 was promoted by a reduction in the extent of C meth both in its promoter and in the vicinity of its translation start site. The result was validated by revealing the effect of 5-aza-2-deoxycytidine on the C meth status in various seedling organs. An analysis of methylation patterns indicates that the C meth of cytosine-guanine dinucleotides was the most important determinant of transcription, however, the C meth of CHG or CHH trinucleotides had little influence.

To explore the effects of remote ischemic preconditioning on myocardial injury and prognosis after percutaneous coronary intervention (PCI) in patients with acute coronary syndrome.The study was a single center, prospective, randomized, controlled study. A total of 184 patients with unstable angina undergoing elective PCI were randomly assigned to remote ischemic preconditioning group (induced by four times of 5-min inflations of a blood pressure cuff to 200 mmHg around the upper arm, followed by 5-min intervals of reperfusion at 1 h before PCI therapy) or control group (an uninflated cuff around the arm). Successful completion of the PCI eventually included 130 cases of patients, including 72 cases in the remote ischemic preconditioning group and 58 cases in the control group. CK-MB, cTnI, sICAM-1, sVCAM-1 and Hs-CRP levels were measured at 6 am. of the day operating PCI and at 24 h after PCI in the two groups. Major adverse cardiac events were recorded of two groups of patients in the postoperative 6 months. (MACE, including recurrence of angina pectoris, myocardial infarction and death).There were no statistically significant differences in baseline indicators between the 2 groups. CK - MB, cTnI, sICAM-1, sVCAM-1 and Hs-CRP levels in patients with remote ischemic preconditioning group were significantly lower than those form the control group after PCI (p0.05), but there were no significant differences between the occurrence of MACE in the postoperative 6 months (p0.05).Remote ischemic preconditioning can reduce PCI related myocardial injury and protect vascular endothelial function.

In the past decades, it has become clear that superoxide radical (O2·−) can be generated from photosystem II (PSII) during photosynthesis. Depending on the extent of its accumulation, O2·− plays an important role in plant physiology and pathology. The photoinhibition/repair cycle is a typical process in PSII which is mainly responsible for the survival of plants under the photoinihibition condition. It is therefore of significant importance to determine O2·− production in this cycle, and then explore how O2·− is controlled by PSII within a normal physiological level. With this in mind, we herein investigate the variation of the O2·− levels in PSII under Mn-depleted and photoactivated conditions mimicking the photoinhibition/repair cycle in vitro. The effect of intrinsic SOD-like component on the O2·− levels was also studied. Results show that PSII has the ability to regulate the O2·− levels in these two processes by simultaneously modulating the O2·− generation activity and intrinsic SOD-like activity. This finding could shed new lights on the photoprotective property of PSII against O2·− and other reactive oxygen species.

By introducing ZrO2 (4Y) powder into the thermit, Al2O3/ZrO2 (4Y) composite ceramics were prepared through combustion synthesis under high gravity, and the correlations of composition, microstructures and mechanical properties of composite ceramics were investigated. The results of XRD, SEM and EDS showed that Al2O3/33%ZrO2 (4Y) were composed of random-orientated rod-shaped colonies consisting of a triangular dispersion of orderly submicron-nanometer t-ZrO2 fibers, surrounded by inter-colony regions consisting of spherically-shaped micronmeter t-ZrO2 grains; Al2O3/45%ZrO2 (4Y) were comprised of spherically-shaped micron-meter t-ZrO2 grains, surround by irregularly-shaped α-Al2O3 grains and a few colonies. Compared to the directionally solidified Al2O3/ZrO2 (Y2O3), the increase in hardness and flexural strength of Al2O3/33%ZrO2 (4Y) in the experiment was due to high densification, small-size defect and high fracture toughness induced by compressive residual stress toughening and transformation toughening mechanisms; meanwhile, in despite of the moderate decrease in hardness, high flexural strength of Al2O3/45%ZrO2 (4Y) was considered to be a result of small-size defect in spherically-shaped micronmeter t-ZrO2 grain matrix and high fracture toughness induced by transformation toughening and micro-crack toughening mechanisms.