Objective To compare the density of acetylcholine receptor (AchR) in orbicular muscle of mouth and gastrocnemius muscle and their affmity with rocuronium, trying to elucidate the mechanism for the difference in the sensitivity of the muscles innervated by facial and peripheral nerve respectively to muscle relaxant.Methods Eight pathogen-free adult male SD rats weighing 180-220 g were used in this study. Muscle strips were isolated from orbicular muscle of mouth and gastrocnemius muscle. Each muscle strip was further divided into 6 smaller and slender strips of same size using dissection microscope. One strip was stained with acetylcholinesterase to measure end-plate surface area (ESA). The other 5 strips were exposed to different concentrations of rocuronium (0, 2.5, 5.0, 7.5, 10.0μg/ml). The mean density of AchR at end-plate was obtained by AchR0/ESA. (AchR0 was defined as the number of AchR per end-plate without being exposed to rocuronium. AchRE was defined as the number of free AchR per end-plate after being exposed to different concentrations of rocuronium. ) The degree of saturation of AchR with different concentrations of rocuronium at each neuromuscular junction was calculated by (AchR0 - AchRE)/AchR0 which reflects the affinity of AchR with the rocuronium in orbicular muscle of mouth and gastrocnemius muscle. Results The density of AchR was significantly lower while the affinity with rocuronium was higher in gastrocnemius muscle than in orbicular muscle of mouth ( P ＜ 0.05). Conclusion The density of AchR is lower and the affinity of AchR at end-plate with rocuronium is significantly greater in gastrocnemius muscle innervated by sciatic nerve than in orbicular muscle of mouth innervated by facial nerve. This may explain the mechanism for different sensitivity of the muscles innervated by facial and peripheral nerves to rocuronium.

ObjectivesTo detect the effects of P-selectin on deep venous thrombosis (DVT) in nephrotic syndrome (NS). and to evaluate the molecular magnetic resonance imaging (MRI) with a P-selectin targeted conlrost agent in diagnosis of thrombosis in the early phase. Methods(1) Forty-one patients with NS hospitalized in our department from 2005 to 2006 were enrolled in this study. They were assigned into DVT group and non-DVT group according to lower limbs radionuclide imaging (RNV) with 99mTc MAA. Blood P-selectin level was measured by ELISA method. (2) P-selectin was detected both in injured vein and blood immediately, 1 h and 3 h after the dog DVT model was established. (3) The P-selectin-targeted contrast agent was developed by conjugating anti-P-selectin lectin-EGF domain monoclonal antibody (PsL-EGFmAb) which was prepared by our lab. The potential of this contrast agent used in vitro molecular imaging experiment as well as in vivo experiment in dog DVT model was investigated. Results (1) Blood P-selectin level was elevated in patients with NS. It was much higher in DVT group than that in non-DVT group. (2) Blood P-selectin level was also elevated in DVT dogs and P-selectin expressed immediately in tunica intima of injured vein and subsequently in thrombus after the model established. (3) Mural thrombus showed higher signal visualization than surrounding muscle in 30 rain after contrast agent injection. These enhanced signals exhibited P-selectin specificity and persisted from the initiation of intima lesions to 3 h after development of thrombosis. There was signficant Differences in contrast-to-noise ratio (CNR) of the experiment group and the control group (11.50±2.32 vs 2.71±0.86, P＜0.01). The same results were derived from 30 rain to 1 hafter contrast agent being injected in distal to heart part of the injured vessel, and the signal decreased 24 h later. Differences in CNR of the experiment group and the control group were also statistically significant (10.40±2.15 vs 1.93±0.57, P＜0.01). Moreover, the contrast agent did not affect the vital signs of the dog. The function of the heart, lung, liver and kidney functions remained normal after contrast administration. Conclusions P-selectin*targeted new MR contrast can be used to early locate thrombus in vivo in an early stage, which does not compromise the function of the important organs. It may become a new method for early diagnosis of thrombosis.

BACKGROUNDTo evaluate potential clinical roles of monoclonal antibody (MoAb)-based radioimmunotherapy in the treatment of lung cancer.

METHODSAnti-lung cancer monoclonal antibody LC-l IgM was combined with ⁹⁰Y to produce radioimmunological targeting drug. Human lung cancer tissue was inoculated subcutaneously in 35 nude mice. They were randomized into seven groups while the tumor was 5 mm in diameter. The groups were divided by the dose of the drug injected to the tail vein of the mice: blank group, LC-1 IgM alone, ⁹⁰Y 50 μCi alone, 50 μCi, 150 μCi, 300 μCi, and 400 μCi combined therapy groups. The size of the tumor was measured weekly and the mice were killed in four weeks after treatment. The tumors were resected and weighed.

RESULTSAs compared to blank group, therapy groups' tumor growth was inhibited and the inhibition was dose- and time-dependent. The inhibition rates of 300 μCi and 400 μCi groups were significantly different (P < 0.05). The nuclei of tumor cells showed karyopycnosis, structure disorder and rupture after treatment by pathological exam. In some regions, the tumor cells were necrotic or disappeared.

CONCLUSIONSThe results indicate that the radioimmunological drug made from lung cancer monoclonal antibody LC-1 IgM and ⁹⁰Y can specifically localise in tumor tissue and ensure radioimmunological targeting therapy, so has underlying clinical value.