To assess levels of contamination and human health risk, we analyzed the concentrations of the heavy metals lead (Pb), cadmium (Cd), chromium (Cr), and nickel (Ni) in China’s main deciduous fruits - apple, pear, peach, grape, and jujube. The concentration order of the heavy metals was Ni>Cr>Pb>Cd. In 97.5% of the samples, heavy metal concentrations were within the maximum permissible limits. Among the fruits studied, the heavy metal concentrations in jujube and peach proved to be the highest, and those in grape proved to be the lowest. Only 2.2% of the samples were polluted by Ni, only 0.4% of the samples were polluted by Pb, and no samples were polluted by Cd or Cr. Compared with the other fruits, the combined heavy metal pollution was significantly higher (P<0.05) in peach and significantly lower (P<0.05) in grape. For the combined heavy metal pollution, 96.9% of the samples were at safe level, 2.32% at warning level, 0.65% at light level, and 0.13% at moderate level. In the fruits studied, the contribution of heavy metals to the daily intake rates (DIR) followed the order of Ni>Cr>Pb>Cd. The highest DIR came from apple, while the lowest DIR came from grape. For each of the heavy metals, the total DIR from five studied fruits corresponded to no more than 1.1% of the tolerable daily intake, indicating that no significant adverse health effects are expected from the heavy metals and the fruits studied. The target hazard quotients and the total target hazard quotients demonstrated that none of the analyzed heavy metals may pose risk to consumers through the fruits studied. The highest risk was posed by apple, followed in decreasing order by peach and pear, jujube, and grape. We suggest that the main deciduous fruits (apple, pear, peach, grape, and jujube) of China’s main producing areas are safe to eat.

Somatic nuclear transfer technology has become increasingly promising in biomedicine and agriculture. Whereas the approach remains inefficient and underlying mechanisms remain ambiguous. Although cloned embryos have similar in vitro developmental capacity as in vitro fertilized (IVF) embryos before implantation, they appeared to have much lower full-term developmental efficiency in pig and cattle, and thus it would be reasonable to postulate that profound distinction at the molecular level should exist between them. Herein, RNA sequencing technique was used to screen differentially expressed genes in cloned and IVF blastocysts, and in total 628 differentially expressed transcripts were obtained, among which, 280 transcripts are up-regulated and 348 transcripts are down-regulated in cloned blastocysts. Moreover, one statistically significant pathway associated with endoplasmic reticulum (ER) protein processing was enriched, and some ER-stress markers such as ATF4, ATF6, PDIA3, HSPA1B, HSP40 and HSP90 between cloned and IVF blastocysts were suggested. Additionally, some developmentally important genes such as lipid metabolism related genes (MGLL, DDHD2 and FADS2) and epigenetic modification genes (DNMT1, KDM5C and MBD3L5) were found differentially expressed between cloned and IVF embryos.