In this study, the buffering capacity of amphiphilic pH-sensitivity copolymer poly(2-ethyl-2-oxazoline)-cholesteryl methyl carbonate (PEOZ-CHMC) was evaluated. The ammonium sulfate gradient method was used to prepare doxorubicin hydrochloride (DOX x HCl)-loaded liposomes (DOX-L), and then the post-insertion method was used to prepare PEOZ-CHMC and polyethylene glycol-distearoyl phosphatidyl ethanolamine (PEG-DSPE) modified DOX x HCl-loaded liposomes (PEOZ-DOX-L and PEG-DOX-L). The physico-chemical properties, in vitro drugs release behavior, cellular toxicity and intracellular delivery of liposomes were evaluated, separately. The results showed that PEOZ-CHMC has a satisfactory buffering capacity. The sephadex G-50 column centrifugation method and dynamic light scattering were used to determine the encapsulation efficiency (EE) and particle size of liposomes. The EE and particle size of DOX-L were (97.3 ± 1.4) % and 120 nm, respectively, and the addition of PEOZ-CHMC or PEG-DSPE had no influence on EE and particle size. The zeta potentials of three kinds of liposomes were negative. The release behavior of various DOX liposomes in vitro was investigated by dialysis method. In phosphate buffer solution (PBS) at pH 7.4, DOX x HCl was released from PEOZ-DOX-L in a sustained manner. While in PBS at pH 5.0, the release rate of DOX x HCl from PEOZ-DOX-L increased significantly, which suggested DOX x HCl was released from PEOZ-DOX-L in a pH-dependent manner. The intracellular delivery of liposomes was investigated by confocal laser scanning microscopy (CLSM). The CLSM images indicated that PEOZ-DOX-L showed efficient intracellular trafficking including endosomal escape and release DOX x HCl into nucleus, as well as the DOX-L and PEG-DOX-L had no this effect. The cytotoxicity of liposomes against MCF-7 cells was detected by using MTT assay. The results showed that antiproliferative effects of PEOZ-DOX-L enhanced with pH value decreased, whereas DOX-L and PEG-DOX-L did not have any significant difference in inhibitions at different pH conditions. Therefore, the problems of the inhibition of cellular uptake of liposomes and the failed endosomal escape of pH-sensitive liposomes by PEG chain can be overcome by the pH-sensitive liposomes constructed by PEOZ-CHMC.

Objective To investigate the application values of B-mode ultrasonography , IVU and spiral CT urography (CTU) in duplication of kidney and ureter. Methods Data of the results from B-mode ultrasonography , IVU and spiral CTU on 85 cases with duplication of renal pelvis and ureter were retrospectively analyzed. Results The diagnostic accordance rates of B-mode ultrasonography , IVU and spiral CTU for duplication of kidney and ureter were 44.7%, 60.0% and 100%, respectively. CTU examination and image post-processing could clearly display the locations and degrees of dilatation or obstruction in duplication of kidney and ureter, and could also display the ectopic location and assess renal function. Conclusion The diagnostic accuracy rate of CTU examination and image post-processing for duplication of kidney and ureter is higher than those of B-mode ultrasonography and IVU.

A 63-year-old female patient underwent coronary CT angiography and received an intravenous iohexol injection(350 mg/ ml )80 ml as the contrast agent. At the sixth minutes of observation after CT test completion,the patient developed palm itching,bilateral conjunctival congestion and edema, sweating,vertigo,nausea,and vomiting a small amount of gastric contents and then followed by lip cyanosis, facial edema,cold limbs,skin ecchymosis,and bleeding the injection site. Blood gas analysis showed an oxygen saturation of 0. 83 and an oxygen partial pressure of 47 mmHg. About an hour after CT scan,the laboratory test revealed the following levels:blood platelet count 19 × 109 / L,prothrombin time(PT)18 s, and thrombin time( TT)6 s. Treatments with anti-anaphylaxis,coagulation factor supplementation,and correction of acidosis and electrolyte disorder were given. After 7. 5 hours after CT scan,her blood platelet count was 8 ×109 / L. The next day,large pieces of skin ecchymosis appeared in many parts of her body,a body temperature reached 38. 1 ℃ and a blood platelet count was 6 × 109 / L. Symptomatic and supportive therapy was continued and her condition gradually improved. On day 4,she presented with normal temperature,disappeared facial edema,and relief of skin ecchymosis. On day 6,her level of blood platelet and all the values of coagulation functions returned to normal.

A 63-year-old female patient underwent coronary CT angiography and received an intravenous iohexol injection(350 mg/ ml )80 ml as the contrast agent. At the sixth minutes of observation after CT test completion,the patient developed palm itching,bilateral conjunctival congestion and edema, sweating,vertigo,nausea,and vomiting a small amount of gastric contents and then followed by lip cyanosis, facial edema,cold limbs,skin ecchymosis,and bleeding the injection site. Blood gas analysis showed an oxygen saturation of 0. 83 and an oxygen partial pressure of 47 mmHg. About an hour after CT scan,the laboratory test revealed the following levels:blood platelet count 19 × 109 / L,prothrombin time(PT)18 s, and thrombin time( TT)6 s. Treatments with anti-anaphylaxis,coagulation factor supplementation,and correction of acidosis and electrolyte disorder were given. After 7. 5 hours after CT scan,her blood platelet count was 8 ×109 / L. The next day,large pieces of skin ecchymosis appeared in many parts of her body,a body temperature reached 38. 1 ℃ and a blood platelet count was 6 × 109 / L. Symptomatic and supportive therapy was continued and her condition gradually improved. On day 4,she presented with normal temperature,disappeared facial edema,and relief of skin ecchymosis. On day 6,her level of blood platelet and all the values of coagulation functions returned to normal.