Correlation between DNA methylation and chronological age of Moso bamboo (Phyllostachys heterocycla var. pubescens)

Abstract Background Chronological age is the primary consideration when studying the physiological development, aging, and flowering of bamboo. However, it’s difficult to determine bamboo’s chronological age if the time of germination is unknown. To investigate the chronological age of bamboo from the genomic DNA methylation profile, methylation-sensitive amplification polymorphism (MSAP) was employed to analyze the genomic DNA methylation of Moso bamboo (Phyllostachys heterocycla var. pubescens) from stands of nine germination-ages, using six primer pairs which have previously been shown to yield methylation rates that reflect the age of Moso bamboo. Results The results showed that the total genomic DNA methylation rates in Moso bamboo at different chronological ages were significantly different, and the increase in genomic DNA methylation rate was consistent with the increase of chronological age. Six primer pairs displayed different genomic DNA methylation rates in Moso bamboo of nine age’s group; however, a significantly positive correlation existed among these primer pairs. An integrated index was obtained by performing principal component analysis on the six primer pairs to represent the genomic DNA methylation levels in Moso bamboo of various chronological ages, and a quadratic curve between the chronological age and genomic DNA methylation levels was obtained. Conclusions Such a relationship between DNA methylation and its chronological age may serve a reference for its aging study in Moso bamboo. </jats:sec

Vasopressin and epinephrine versus epinephrine in management of patients with cardiac arrest: a meta-analysis

Objective. A combination of vasopressin and epinephrine may be more effective than epinephrine alone in cardiopulmonary resuscitation (CPR), but evidence is lacking to make clinical recommendations. This meta-analysis compares the efficacy of vasopressin and epinephrine used together versus epinephrine alone in cardiac arrest (CA). Methods. We searched MEDLINE and EMBASE for randomized trials comparing the efficacy of vasopressin and epinephrine versus epinephrine alone in adults with cardiac arrest. The primary outcome was the return of spontaneous circulation (ROSC) and the survival rate on admission and discharge .We also analyzed ROSC in subgroups of patients presenting with different arrest rhythms, such as asystole, pulseless electrical activity (PEA), ventricular fibrillation (VF). Results. We analyzed 6 randomized trials out of 485 articles. We did not find evidence supporting the superiority of vasopressin and epinephrine used in combination, except for the survival rate at 24h 2.99 95% CI(1.43,6.28). No evidence supports the conclusion that vasopressin combined with epinephrine is better than epinephrine alone for ROSC, even amongst subgroups of patients. Conclusion. This systematic review of the efficacy of vasopressin and epinephrine use found that its combined use is better for 24h survival rate but only in one study which included 122 patients. Further investigation will be needed to support the use of this combination for cardiac arrest management