Effects of nanographene oxide on adipose-derived stem cell cryopreservation.

Cryoinjury mitigation is key in cell cryopreservation. Here, we aimed to assess the effectiveness of nanographene oxide (nano-GO) for improving cryoprotectant agents (CPAs) in human adipose stem cell (hADSC) cryopreservation. For in vitro experiments, nano-GO (5 µg/mL) was added to the CPAs in the control, and passage (P) 2 hADSCs were collected and cryopreserved for around two weeks. We compared cytotoxicity, cell viability, immunophenotypes, proliferation, cell apoptosis, and tri-lineage differentiation. In vivo, studies used lipoaspirate to create non-enriched or hADSC-enriched fat tissues by combining it with PBS or hADSCs cryopreserved with the aforementioned CPAs. Each nude mouse received a 0.3 mL subcutaneous injection of the graft. At 12 weeks, the grafts were harvested. Histology, adipocyte-associated genes and protein, vascular density and angiogenic cytokines, macrophage infiltration, and inflammatory cytokines were analyzed. Nano-GO CPA contributed to increased cell viability, improved cell recovery, and lowered levels of early apoptosis. Nano GO at concentrations of 0.01-100 µg/mL caused no cytotoxicity to hADSCs. The absence of nano GOs in the intracellular compartments of the cells was confirmed by transmission electron microscopy. The fat grafts from the CPA-GO group showed more viable adipocytes and significantly increased angiogenesis compared to the PBS and CPA-C groups. Adding hADSCs from the CPA-GO group to the graft reduced macrophage infiltration and MCP-1 expression. Nano-GO plays an anti-apoptotic role in the cryopreservation of hADSCs, which could improve the survival of transplanted fat tissues, possibly via improved angiogenesis and lower inflammatory response in the transplanted adipose tissue.

Teach them how to fish or give them fish? The effect of collective narcissism on intergroup help.

Intergroup help contributes to the solution of global issues in particular. However, whether to teach an outgroup how to address their problem permanently, or to directly help them solve the current problem? Collective narcissism might play a crucial role in this process. Based on the core characteristics of collective narcissism, this research explored whether and how collective narcissism would affect people's willingness to give different types of intergroup help. Study 1 examined the correlation between collective narcissism and intergroup help. Studies 2 and 3 investigated the impacts of outgroup threat and ingroup image on the relationship between collective narcissism and intergroup help respectively. In Study 4, the interaction between outgroup threat and ingroup image was further examined. The results showed that collective narcissism reduced participants' willingness to offer intergroup help, especially autonomy-oriented help. For low-threat outgroups, collective narcissism increased participants' willingness to give dependency-oriented help. In contrast, collective narcissism increased participants' willingness to give autonomy-oriented help when refusal to intergroup help tarnished the ingroup image. For high-threat outgroups, collective narcissism did not predict participants' willingness to give intergroup help. These findings suggest that collective narcissists' preferences for intergroup help change with outgroup threat and ingroup image.

Subjective economic inequality evokes interpersonal objectification.

Interpersonal objectification, treating people as tools and neglecting their essential humanness, is a pervasive and enduring phenomenon. Across five studies (N = 1183), we examined whether subjective economic inequality increases objectification through a calculative mindset. Study 1 revealed that the perceptions of economic inequality at the national level and in daily life were positively associated with objectification. Studies 2 and 3 demonstrated a causal relationship between subjective economic inequality and objectification in a fictitious organization and society, respectively. Moreover, the effect was mediated by a calculative mindset (Studies 3-4). In addition, lowering a calculative mindset weakened the effect of subjective inequality on objectification (Study 4). Finally, increased objectification due to subjective inequality further decreased prosociality and enhanced exploitative intentions (Study 5). Taken together, our findings suggest that subjective economic inequality increases objectification, which further causes adverse interpersonal interactions.