OBJECTIVE: The pH-sensitive procationic liposomes were prepared, with hydroxycamptothecin (HCPT) as model drug. METHODS: The cationic liposomes were prepared by film dispersion method. The encapsulation efficiency was determined after removing unentrapped HCPT by Sephadex-G50 chromatographic column. Carboxymethyl chitosan was used to coat the cationic liposomes, then the liposomes were extruded through high pressure homogenizer. Zetasizer was used to determine the zeta potential, average size of the HCPT liposomes. pH sensitivity analysis was made through experiments of red blood cell hemolysis and tumor distribution is analysised. RESULTS: The size of liposomes was around 96 nm and drug encapsulation efficiency was 78.5%. The membrane fusion of red blood cells with procationic liposomes was significantly different between pH 6.5 and pH 7.4 and the in vivo experiments in tumor-bearing mice suggested that they had a high tumor distribution. CONCLUSION: The pH-sensitive procationic nanoliposomes were easy to prepare and were expected to be a promising anti-tumor drug delivery system. Copyright 2012 by the Chinese Pharmaceutical Association.

DNA, Neoplasm ; analysis ; Female ; Flow Cytometry ; Humans ; Hydatidiform Mole ; diagnosis ; genetics ; In Situ Hybridization, Fluorescence ; Microsatellite Repeats ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length ; Pregnancy ; Triploidy ; Uterine Neoplasms ; diagnosis ; genetics

To review recent studies on the research advance of RET( Rearranged during transfection) on-cogene in thyroid cancer,breast cancer,and lung cancer.The literatures on the structure of RET gene and coding product,cell signal transduction,relationship among thyroid cancer,breast cancer,and lung cancer are reviewed. RET gene encoding tyrosine kinase receptor,involving in cell signal transduction,rearrangement of RET gene is frequently seen in thyroid cancer,which is reported more and more in breast cancer,and lung cancer.Rearrange-ment of RET gene is closely correlated with the occurrence and progress of thyroid cancer,breast cancer,and lung cancer.Taking together,these findings suggest that RET present an attractive therapeutic target for the treatment of certain cancer subsets.

Objective To explore the effects of advanced glyeosylation end products (AGEs) on the binding of hepatic nuclear factors to the human insulin receptor (hlR) gene promoter. Methods The oligonueleotides with hlR gene promoter activity, 42 bp (spanning -1 441 to -1 400, US1) or 146 bp (spanning -638 to -493), were artificially synthesized, with point mutations at 5 key G residues in 42 bp US1 m5 oligonucleotides. US1 and rat hepatic nuclear extracts (HNE) were incubated with glucose 6-phosphate, prior to non-competition and competition gel retardation electrophoresis. Results Competition gel retardation electrophoresis showed that the binding capacity of 32p-labeled US1 probe to HNE could be signifficantly decreased with increased US1. US1-AGEs and US1m5 decreased the binding of probe to HNE as well, but only partly affected the electrophoretie bands [1,5,10 ng US1-AGEs: (41.08±2.86)%, (27.64±2.92)%, (15.35±1.81%) vs (52.05±1.79)%]; 5,10 ng US1m5: (5.20± 1.03)%, (1.81±0.21)% vs (52.05±1.79)%]. AGEs formed on HNE could increase the binding of HNE to probe, along with nonspecifie binding increasing. Conclusion The impact of AGEs on hlR gene expression seems to be related to the effects on cis-elements and trans-acting factors.

Adult ; Aged ; Erythrocyte Indices ; Hemorheology ; Humans ; Male ; Middle Aged ; Silicosis ; blood

Humans ; Microbial Sensitivity Tests ; Pneumoconiosis ; diagnosis ; microbiology ; Sputum ; microbiology

OBJECTIVETo investigate the effect of midazolam on human ether-a-go-go (hERG) K+ channels exogenously expressed in human embryonic kidney cells (HEK-293) and the underlying molecular mechanisms.

METHODSWhole-cell patch clamp technique was used to record WT, Y652A and F656C hERG K+ current expressed in HEK-293 cells.

RESULTSMidazolam inhibited hERG K+ current in a concentration-dependent manner, the half-maximum block concentrations (IC50) values were (1.31 ± 0.32) µmol/L. The half-activation voltage (V1/2) were (2.32 ± 0.38) mV for the control and (-1.96 ± 0.83) mV for 1.0 µmol/L midazolam. The half-inactivation voltage (V1/2) was slightly shifted towards negative voltages from (-49.25 ± 0.69) mV in control to (-57.53 ± 0.53) mV after 1.0 µmol/L midazolam (P < 0.05). Mutations in drug-binding sites (Y652A or F656C) of the hERG channel significantly attenuated the hERG current blockade by midazolam.

CONCLUSIONMidazolam can block hERG K+ channel and cause the speed of inactivation faster. Mutations in the drug-binding sites (Y652 or F656) of the hERG channel were found to attenuate hERG current blockage by midazolam.

Dose-Response Relationship, Drug ; Ether-A-Go-Go Potassium Channels ; drug effects ; HEK293 Cells ; Humans ; Midazolam ; pharmacology ; Mutation ; Patch-Clamp Techniques ; Potassium Channel Blockers ; pharmacology

Objective To investigate the association of ret gene rearrangement mutation with the pathogenesis of papillary thyroid carcinoma (PTC). Methods Twenty-seven cases of PTC were analysed for expression of ret gene rearrangement (ret/PTCs) by multiplex-PCR at first, and then ret/PTC1-3 were identified by identification-PCR (ID-PCR). Finally, the specific ret/PTC was affirmed by automated direct sequencing. Ten specimens of malignant thyroid tissues of other histological types, 33 benign thyroid lesions and 30 normal thyroid specimens beside tumor (as the control) were also included. Results (1) Fifteen samples showed positive ret/PTCs, 11 of which harboured ret/PTC1,3 were positive for ret/PTC3, and 1 for ret/PTC2. All the rearrangements were clearly identified by automated direct sequencing of ID-PCR products. (2) All the 15 ret/PTC-positive tissue samples were histologically confirmed to be PTC. The prevalence of the tumor-specific ret rearrangements in 27 patients with PTC is 55.6% (15/27). (3) No significant difference was found regarding the gender and age of the patients, tumor size and metastasis of neck lymph node. 33.3% (2/6) of the PTC with invasion of extrathyroidal soft tissue were ret/PTC-positive, as compared with 66.7%(4/6) for ret/PTC-negative group (P

Objective To investigate the effect of Kanglaite injection (KLT) on immunological function of rat models with Lewis lung carcinoma. Methods Forty C57BL/6 mice were used to establish Lewis lung carcinoma models and divided randomly into the high dose(25 mL/kg), middle dose (12.5 mL/kg) and low dose (6.25 mL/kg) of KLT groups and model group(n=10). The mice in the KLT groups were sacrificed after injecting corresponding dose of KLT with intraperitoneal injection for 14 d. No treatment was performed on the rats in model group. The body weight, tumor and spleen weight was weighed, then the ratio of tumor restriction and the index of spleen was calculated. MTT colorimetric method and ELISA were used to detected activity of T cell proliferation and expression of IL-2 in spleen. The expression of NF-κB and IκBα protein was detected by Western blot. Results The ratio of tumor restriction in the high, middle, low dose of KLT groups decreased gradually. The indexes of spleen of the high and middle dose of KLT groups were higher than those in the model group (P<0.05 or P<0.01).Compared with the model group, the activity of T cell proliferation in the high, middle, low dose of KLT groups and the expression of IL-2 in the high and middle dose of KLT groups was increased significantly (P<0.05 or P<0.01). The expression of NF-κB protein in the nuclei of high, middle, low dose of KLT groups increased dose-dependently, and the expression of NF-κB and IκBα protein in the cytoplasm decreased dose-dependently. ConclusionKLT could enhance immunological function by effecting T cell proliferation, expression of IL-2, NF-κB and IκBα, while restricting tumor growth in Lewis lung carcinoma models.

Adolescent ; Brain Neoplasms ; diagnosis ; Child ; Child, Preschool ; Endocrine System Diseases ; etiology ; Female ; Follicle Stimulating Hormone ; blood ; Humans ; Infant ; Luteinizing Hormone ; blood ; Magnetic Resonance Imaging ; Male ; Tomography, X-Ray Computed