Mechanism underlying earthworm on the remediation of cadmium-contaminated soil.

Cadmium (Cd) contamination of soil becomes a potential agricultural and global environmental problem due to the need to ensure safe food. In this study, earthworms (Eisenia fetida) and plants (vetiver grass) were prepared for removal Cd from soil. The results showed the Cd concentration in the soil of all experimental groups decreased, notably by 17.60% in the group with 20 mg/kg Cd concentration. In the roots of vetiver, the content of Cd increased by 57% after earthworms were added and the transfer coefficient of Cd was also significantly increased. Moreover, Cd in the soil was generally absorbed by the intestinal tract of earthworms and became concentrated, mainly in the midgut and hindgut accounting for >77.78% of the total. In addition, enteric microorganism analysis demonstrated that the bacterial community structure played an important role in Cd enrichment and metabolism regulation. There was a significant correlation between some bacteria and Cd concentration. Among these bacteria, Pseudomonas brenneri, were involved in the adsorption and metabolism of Cd to reduce the toxicity of Cd to the earthworms. On the other hand, in order to cope with the external Cd stress, the malondialdehyde (MDA) and hydrogen critically (CAT) enzymes in the earthworms increased with the concentration. Therefore, the high tolerance of earthworms to Cd is related to its physiological adjustment and the balance of intestinal bacteria. The combination of earthworms, microorganisms and plants can result a good alternative to diminish the impact of Cd in soils.

Hydrogel derived from decellularized porcine adipose tissue as a promising biomaterial for soft tissue augmentation.

Decellularized extracellular matrix (ECM) scaffolds from human adipose tissue, characterized by impressive adipogenic induction ability, are promising for soft tissue augmentation. However, scaffolds from autologous human adipose tissue are limited by the availability of tissue resources and the time necessary for scaffold fabrication. The objective of the current study was to investigate the adipogenic properties of hydrogels of decellularized porcine adipose tissue (HDPA). HDPA induced the adipogenic differentiation of human adipose-derived stem cells (ADSCs) in vitro, with significantly increased expression of adipogenic genes. Subcutaneous injection of HDPA in immunocompetent mice induced host-derived adipogenesis without cell seeding, and adipogenesis was significantly enhanced with ADSCs seeding. The newly formed adipocytes were frequently located on the basal side in the non-seeding group, but this trend was not observed in the ADSCs seeding group. Our results indicated that, similar to human adipose tissue, the ECM scaffold derived from porcine adipose tissue could provide an adipogenic microenvironment for adipose tissue regeneration and is a promising biomaterial for soft tissue augmentation. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1756-1764, 2017.