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Melatonin is capable of improving the developmental capacity of ovine, porcine and bovine embryos in vitro. However, whether melatonin possesses similar benefits to the in vitro mouse embryonic development has yet to be determined. In this study, we assessed the effects of various concentrations of melatonin (10–13 to 10–3 M) on the in-vitro development of mouse embryos cultured in HTF medium for 96 hr; embryos cultured without melatonin were used as control. The in vitro development of mouse two-cell embryos significantly benefited from treatment with melatonin in a concentration-dependent manner. The effects of melatonin on the rates of blastocyst formation, hatching/hatched blastocysts and cell number per blastocyst were bi-phasic; all significantly increased by melatonin at 10–13 to 10–5 M and decreased by melatonin at 10–3 M. Maximal benefit of melatonin on in vitro mouse 2-cell embryo development was achieved at a concentration of 10–9 M. In comparison to control, 10–9 M melatonin increased blastocyst formation rate from 48.08 ± 5.25% to 82.08 ± 2.34% (p < 0.05), hatched blastocyst rate from 25.65 ± 11.79% to 66.47 ± 4.94% (p < 0.05), and cell number per blastocyst 62.71 ± 5.97 to 77.91 ± 10.63 (p < 0.05). Thus, our datas demonstrated firstly that melatonin has beneficial effects on the in vitro development of 2-cell mouse embryos cultured in HTF medium. [ABSTRACT FROM AUTHOR]

Objective To explore the association between plasma homocysteine (Hcy) level and hyper-uricemia (HUA) in the elderly patients with hypertension.Methods From March to August in 2018,9902 hypertensive patients ≥ 60 years were routinely tested for blood biochemical indicators in Wuyuan county,Jiangxi province.The patients were assigned into a HUA group and a normal uric acid group.Multivariate Logistic regression was adopted to analyze the relationship between Hcy level and the risk of HUA.Results Compared with the normal uric acid group,the HUA group showed increased incidence of hyperhomocysteinemia (99.9% vs. 98.7%, P <0.001) and elevated Hcy level[16.8 (13.8-21.5) μmol/L vs. 14.4 (12.3-17.7) μmol/L, P <0.001].The multivariate Logistic regression analysis showed that after adjusting for influencing factors,the risk of HUA in the patients with hyperhomocysteinemia was 2.92 times of that in the patients with a normal Hcy level.The threshold effect analysis showed that the Hcy level was positively correlated with the occurrence of HUA in the case of Hcy<20 μmol/L ( OR =1.05,95% CI =1.04-1.07, P <0.001).In the case of Hcy ≥ 20 μmol/L,there was no correlation between Hcy level and HUA ( OR =1.00,95% CI =0.99-1.00, P =0.055),and the likelihood ratio test showed statistically significant results ( P <0.001).Conclusion The elderly with hypertension should pay attention to control the Hcy level,which will be helpful to prevent the occurrence of HUA.

Electrode materials with high activity and good stability are essential for commercialization of energy conversion systems such as solid oxide fuel cells or electrolysis cells at the intermediate temperature. Modifying the existing perovskite-based electrode surface to form a heterostructure has been widely applied for the rational design of novel electrodes with high performance. Despite many successful developments in enhancing electrode performance by surface modification, some controversial results are also reported in the literature and the mechanisms are still not well understood. In this work, the mechanism of how surface modification impacts the oxygen reduction reaction (ORR) activity and stability of perovskite-based oxides was investigated. We took La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3 (LSCF) as the thin-film model system and modified its surface with additive Pr x Ce 1- x O 2 layers of different thicknesses. We found a strong correlation between surface oxygen defects and the ORR activity of the heterostructure. By inducing higher oxygen vacancy concentration compared to bare LSCF, PrO 2 coating is proved to greatly facilitate the rate of oxygen dissociation, thus significantly enhancing the ORR activity. Because of low oxygen vacancy density introduced by Pr 0.2 Ce 0.8 O 2 and CeO 2 coating, on the one hand, it does not boost the rate of ORR but successfully suppresses surface Sr segregation, leading to an enhanced durability. Our findings demonstrate the vital role of surface oxygen defects and provide important insights for the rational design of high-performance electrode materials through surface defect engineering.

To detect the ecological process of the succession series of Phyllostachys glauca forest in a limestone mountain, five niche models, i.e., broken stick model (BSM), niche preemption model (NPM), dominance preemption model (DPM), random assortment model (RAM) and overlap- ping niche model (ONM) were employed to describe the species-abundance distribution patterns (SDPs) of 15 samples. χ² test and Akaike information criterion (AIC) were used to test the fitting effects of the five models. The results showed that the optimal SDP models for P. glauca forest, bamboo-broadleaved mixed forest and broadleaved forest were DPM (χ² = 35.86, AIC = -69.77), NPM (χ² = 1.60, AIC = -94.68) and NPM (χ² = 0.35, AIC = -364.61), respectively. BSM also well fitted the SDP of bamboo-broadleaved mixed forest and broad-leaved forest, while it was unsuitable to describe the SDP of P. glauca forest. The fittings of RAM and ONM in the three forest types were all rejected by the χ² test and AIC. With the development of community succession from P. glauca forest to broadleaved forest, the species richness and evenness increased, and the optimal SDP model changed from DPM to NPM. It was inferred that the change of ecological process from habitat filtration to interspecific competition was the main driving force of the forest succession. The results also indicated that the application of multiple SDP models and test methods would be beneficial to select the best model and deeply understand the ecological process of community succession.

Objective: The objective of this study was to investigate the effects of seasonal changes on the superovulation in Black Suffolk ewes, particularly the ovulation rate and embryo quality., Design: Black Suffolk ewes were superovulated either in May (n=22) or in September (n=21), 2013. After estrus synchronization with CIDR, the donor ewes were superovulated with PMSG and seven decreasing doses of FSH (twice daily at 07:00 and 19:00 for four consecutive days. Then, they were subjected to laparoscopic intrauterine artificial insemination. The viable morula and blastocysts were recovered and immediately transferred to recipients., Results: Ewes that were superovulated in May had a much higher ovulation rate than those were superovulated in September (16.8 ± 3.23vs. 10.2 ± 2.94, p<0.01); however, the viability rate of the embryo was lower than that of September (56.0 ± 1.92% vs. 92.5 ± 3.26%, p<0.01). There was no significant difference in the survival rate of the transferred viable embryos (33.9 ± 1.00% vs. 36.7 ± 1.64%, p>0.05) and the number of offspring per donor ewe (3.1 ± 0.54 vs. 2.9 ± 0.72, p>0.05) between May and September. In contrast, the offspring/ova ratio of the donor ewes superovulated in May was lower than that of September (18.5 ± 1.64% vs. 32.8 ± 2.14%, p<0.01)., Conclusions: The superovulation of Black Suffolk ewes may be affected by the seasonal changes. Generallly, The ewe's ovulation rate was higher in May, whereas the viability rate of embryo was higher in September.

Farmed blue fox was used as a model to develop cryopreservation protocol for nondomestic canine species. We report here the developmental potential of farmed blue fox oocytes after vitrification with a two-step OPS method. Oocytes were collected and pre-cultured for 0, 24, 48, 72 hours respectively before cryopreservation. Vitrification of oocytes was achieved by a 30 sec treatment in 10% ethylene glycol (EG) or 10% EG + 10% dimethyl sulfoxide (DMSO) at 25 degree C followed by a 25 sec equilibration in EFS30 (30% (v/v) EG +21% (w/v) Ficoll +0.35M sucrose) or EDFS30 (15% (v/v) EG +15% (v/v) DMSO +21% (w/v) Ficoll +0.35M sucrose), before plunging into liquid nitrogen. The survival of oocytes after vitrification was assessed morphologically immediately after warming, and cultured for in vitro maturation. For comparison, control oocytes were cultured for in vitro maturation for 96 hours. The best result was obtained when oocytes were pre-cultured for 72 hours, first exposed to 10 percent EG + 10% DMSO and vitrified in EDFS30. The survival percentage of oocytes under these conditions was not significantly different (P > 0.05) from that of the control.