Polyamidoamine dendrimer liposome-mediated survivin antisense oligonucleotide inhibits hepatic cancer cell proliferation by inducing apoptosis.

Polyamidoamine dendrimer (PAMAM) is a new nanometer material, which can transfer the target genes to cells with high efficiency and lower toxicity. This study aims to evaluate antitumor effects of survivin antisense oligonucleotide (survivin-asODN) (carried by polyamidoamine dendrimer liposome) on hepatic cancer in nude mice. Hepatic cancer model was established by injecting SMMC-7721 cells subcutaneously into flanks of nude mice. Polyamidoamine dendrimer and liposome were mixed with survivin-asODN, respectively. The shape and size of complex were observed by transmission electron microscope, and zeta potential was measured by an analytical tool. Encapsulation efficiency and DNA loading level were determined by an ultraviolet spectrophotometer in centrifuging method. Expression of survivin in transplant tumor was measured by Western blotting. No significant difference appeared for diameter and envelopment ratio between PAMAM liposome-survivin-asODN and PAMAM-survivin-asODN (P > 0.05). Both zeta potential and transfection efficiency in PAMAM liposome-survivin-asODN were higher than that in PAMAM-survivin-asODN complex (P < 0.05). Expression of survivin protein and weight of tumors in transplanted tumors in PAMAM liposome-survivin-asODN group was less than that in PAMAM-survivin-asODN group (P < 0.05). Cell apoptosis rate in PAMAM liposome-survivin-asODN group was higher than that of PAMAM-survivin-asODN group (P < 0.05). In conclusion, polyamidoamine dendrimer liposome can deliver survivin-asODN into hepatic transplanted tumor cells effectively. Ployamidoamine dendrimer liposome-mediated survivin-asODN can inhibit hepatic cell proliferation by inducing apoptosis.

[Hydrolysis of COS over MgAl Mixed Oxides Derived from Hydrotalcites].

A series of MgAl hydrotalcite-derived composite oxides were prepared by co-precipitation methods. The effects of calcination temperature, reaction temperature, water vapor volume fraction, and alkali metal addition on the hydrolysis activity of the samples were investigated. The crystal structure, specific surface area, pore structure, and basic position distribution of the composite oxides were characterized using XRD, BET, TPD, and XPS. The results shown that the catalytic activity firstly increased and then decreased with the rise of calcination temperature. Furthermore, the sample that calcined at 650℃ can achieve the best catalytic activity (complete removal of COS lasted for 180 min). Increasing the reaction temperature improved the catalytic activity, which can present excellent catalytic activity and stability at temperatures above 70℃. In addition, the doping of the alkali metal Cs improved the catalytic activity, the complete removal time for COS can be maintained for 480 min.

Mechanism of nitric oxide and acid-sensing ion channel 1a modulation of panic-like behaviour in the dorsal periaqueductal grey of the mouse.

Predators induce defensive responses and fear behaviours in prey. The rat exposure test (RET) is frequently used as an animal model of panic. Nitric oxide (NO) which has been reported to be activated by the NMDA receptor, in turn mediates calcium/calmodulin-dependent protein kinase II (CaMKII) signalling pathways in defensive responses. ACCN2, the orthologous human gene of acid-sensing ion channel 1a (ASIC1a), is also associated with panic disorder; however, few studies have focused on the role of ASIC1a in the modulation of panic and calcium/CaMKII signalling by NO. In the present study, NG-nitro-L-arginine-methyl-ester (L-NAME; non-selective NOS inhibitor), S-nitroso-N-acetyl-D,L-penicillamine (SNAP; NO donor), and psalmotoxin (PcTx-1; selective ASIC1a blocker) were administered to the dorsal periaqueductal grey (dPAG) before the predator stimulus, and the roles of NO in the expression of ASIC1a, phosphorylation of CaMKIIα (p-CaMKIIα) and expression of calmodulin (CaM) were investigated. The effects of ASIC1a, p-CaMKIIα and CaM regulation were also examined. Our results showed that intra-dPAG infusion of L-NAME weakened panic-like behaviour and decreased ASIC1a, p-CaMKIIα and CaM expression levels, whereas intra-dPAG infusion of SNAP enhanced panic-like behaviour and increased ASIC1a, p-CaMKIIα and CaM levels. Intra-dPAG infusion of PcTx-1 also weakened panic-like behaviour and decreased p-CaMKIIα expression level. Taken together, these results indicate that NO and ASIC1a are involved in the modulation of RET-induced panic-like behaviour in the dPAG. NO regulates the calcium/CaMKII signalling pathways, and ASIC1a participates in this regulation.

The effects of light exposure during incubation on embryonic development and hatchling traits in lizards.

Light is an environmental factor that is known to profoundly affect embryonic development in some oviparous vertebrates, but such effects are unstudied in reptiles. We investigated the light sensitivity of lizard embryos by examining the thickness and light transmittance of eggshells as well as the effect of light on embryonic development and hatchling traits in four lizard species, the Chinese skink (Plestiodon chinensis), the northern grass lizard (Takydromus septentrionalis), the oriental leaf-toed gecko (Hemidactylus bowringii) and the Japanese gecko (Gekko japonicus). The eggshells were thinner and thus had higher light transmittance in Chinese skink than the other three species. Light exposure during incubation significantly accelerated the embryonic development in all species, with higher light intensity resulting in faster embryonic development. Interestingly, light stimulation negatively influenced hatchling size and survival in skinks, but had no effect in lacertids and geckos. This interspecific discrepancy not only relates to the differences in thickness and light transmittance of eggshells, but might also reflect the differences in the reproductive habits of these species. Given the diversity of light conditions that reptile embryos face during development, studies on the response of reptile embryos to light may offer a unique opportunity to understand the mechanisms of embryonic light sensitivity in animals.