Responsive Hydrogels Based on Triggered Click Reactions for Liver Cancer.

Globally, liver cancer, which is one of the major cancers worldwide, has attracted the growing attention of technological researchers for its high mortality and limited treatment options. Hydrogels are soft 3D network materials containing a large number of hydrophilic monomers. By adding moieties such as nitrobenzyl groups to the network structure of a cross-linked nanocomposite hydrogel, the click reaction improves drug-release efficiency in vivo, which improves the survival rate and prolongs the survival time of liver cancer patients. The application of a nanocomposite hydrogel drug delivery system can not only enrich the drug concentration at the tumor site for a long time but also effectively prevents the distant metastasis of residual tumor cells. At present, a large number of researches have been working toward the construction of responsive nanocomposite hydrogel drug delivery systems, but there are few comprehensive articles to systematically summarize these discoveries. Here, this systematic review summarizes the synthesis methods and related applications of nanocomposite responsive hydrogels with actions to external or internal physiological stimuli. With different physical or chemical stimuli, the structural unit rearrangement and the controlled release of drugs can be used for responsive drug delivery in different states.

In vitro comparison of the biological activity of alumina ceramic and titanium particles associated with aseptic loosening.

Prosthetic wear particles are thought to play a central role in the initiation and development of periprosthetic osteolysis, leading to aseptic loosening of prostheses. This study aimed to compare the biological activity of ceramic and titanium particles that are associated with particle-induced, aseptic joint loosening. Different sizes of alumina-ceramic particles and titanium particles were prepared to stimulate murine macrophage cells RAW 264.7, of which the expressions of tumor necrosis factor alpha (TNF-alpha) and receptor activator of nuclear factor-κB ligand (RANKL) were measured by qPCR and ELISA at various time points. In the presence of all particles, the expression of TNF-alpha increased in a time-dependent manner, whereas the expression of RANKL showed no regular expression patterns. Notably, particles of smaller sizes provoked significantly higher levels of TNF-alpha and RANKL than those of larger sizes. Compared to the titanium particles, the ceramic particles provoked a significantly lower production of TNF-alpha. Thus, the bioactivities of titanium and alumina ceramic particles were inversely proportional to the sizes of the particles, and the expression of RANKL was not parallel to that of TNF-alpha. The successful outcome of ceramic-on-ceramic artificial joint prostheses may be attributed to the low biological activity of ceramic particles, as evidenced here.

[Effect of chemical modification of grafts on the survival improvement post haploidentical bone marrow transplantation in mice].

OBJECTIVE: Human leukocyte antigen (HLA) haploidentical bone marrow is a potential source of donor to children for its availability. The drawback is deleterious graft versus host disease (GVHD) reaction post transplantation because of the incompatibility of HLA antigen expression between donors and recipients, in which donor T lymphocyte is stimulated to proliferate and differentiate. The methoxy polyethylene glycol (mPEG) is a kind of amphoteric compound without immunogenicity, which was used to modify various proteins covalently and to prepare the versatile blood type. If mPEG modification blocks the activation of T cells in grafts, GVHD reaction probably would become less serious and transplantation might become successful. The aim of this study was to verify the improvement of haploidentical bone marrow transplantation (BMT) in a murine model by using mPEG of certain concentration to modify the grafts. METHODS: Male BALB/c mice were chosen as the donor, and female CB(6)F(1) mice as the recipient. There were three groups of mPEG modification, non-modification and irradiation control, and 20 mice in each group. The modified and non-modified mixture of bone marrow and spleen cells (as T lymphocytes) were transplanted to haploidentical lethally irradiated CB(6)F(1) mice via the tail vein. After the transplant, the hematopoietic recovery, survival rate, acute graft versus host disease (aGVHD) and chromosomal karyotype were analyzed and compared with controls. RESULTS: Seventy-five percent (15/20) of mice survived in the group of mPEG modification, while only 40% (8/20) survived in the group without the modification (chi(2) = 5.01, P = 0.025). And 100% mice died in the group of the irradiation control within 2 weeks. The hematopoietic recovery in the group of mPEG modification was show n to be faster than that in the group without modification (P < 0.05). Histopathological examination of the skin, liver and intestine showed typical signs of aGVHD, but the GVHD grading in the group of modification was less severe. The recipient mice in both groups of transplantation surviving for more than 75 days showed complete donor-type implantation by the chimerism examination. CONCLUSION: The modification of grafts by mPEG could alleviate aGVHD and improve the survival rate of mice after the haploidentical bone marrow transplantation.