Use of 5-Fluorouracil Loaded Micelles and Cisplatin in Thermosensitive Chitosan Hydrogel as an Efficient Therapy against Colorectal Peritoneal Carcinomatosis.

Colorectal peritoneal carcinomatosis (CRPC) is a common systemic metastasis of intra-abdominal cancers. Intraperitoneal chemotherapy against CRPC is at present the preferred treatment. The aim of this study is to develop a novel hydrogel drug delivery system through the combination of 5-fluorouracil (5-FU) loaded polymeric micelles and cisplatin (DDP) in biodegradable thermosensitive chitosan (CS) hydrogel. The prepared CS hydrogel drug is a free-flowing solution at room temperature and forms a stationary gel at body temperature. Therefore, a CRPC mouse model is established to investigate the antitumor activity of CS hydrogel drug system. The results suggest that intraperitoneal administration of CS hydrogel drug can inhibit tumor growth and metastasis, and prolong survival time compared with other groups, thus improving the chemotherapeutic effect. Ki-67 immunohistochemical analysis reveals that tumors in the CS hydrogel drug group has lower cell proliferation in contrast to other groups (P < 0.001). Furthermore, hematoxylin-eosin staining of liver and lung tissue indicates that the CS hydrogel drug has also a certain inhibitory effect on colorectal cancer metastasis to the liver and lung. Hence, the work highlights the potential clinical applications of the CS hydrogel drug.

[Determination of 1, 1-dichloro-l-nitroethane in air of workplaces by gas chromatography].

OBJECTIVE: To establish a gas chromatography method for detecting the concentration of 1,1-dichloro-1-nitroethane in air of workplaces. METHOD: 1,1-dichloro-1-nitroethane in air of workplaces was collected by activated charcoal tube, absorbed using carbon disulfide and analyzed by Gas Chromatography (FID) with FFAP capillary column. RESULTS: The linear rang of 1,1-dichloro-1-nitroethane in this method was 4.0-858.2 microg/ml, the linear regression formula was Y = 283X-1076, the correlation coefficient was 0.9999, the lowest detection concentration was 0.4 mg/m3 (3L sampling air), the relative standard deviation (RSD) was 1.8%-4.1%, the desorption efficiency was 88.5%-90.6%, the breakthrough volume was > 0.7 mg, the sampling efficiency was 100%, the samples could be kept at ambient temperature for at least 7 days. CONCLUSION: The indicators of this method were conformed to the requirements of "Guide for establishing occupational health standards--Determination methods of air chemicals in workplace". This method could be used to detect 1,1-dichloro-1-nitroethane in air of workplaces.