Sevoflurane preconditioning prevents acute renal injury caused by ischemia-reperfusion in mice via activation of the Nrf2 signaling pathway.

Oxidative stress, caused by renal ischemia reperfusion (IR)/hypoperfusion, is one of the main causes of acute kidney injury (AKI). Previous studies have demonstrated that sevoflurane (SEV) protects organs from the damage caused by oxidative stress. In the present study, mice were randomly assigned to a sham operation group (Sham), IR-vehicle group (IR+ vehicle), IR + SEV low-dose preconditioning group and an IR + SEV high-dose preconditioning group. The effect of SEV on nuclear factor E2-related factor 2 (Nrf2), a key regulatory protein of the endogenous antioxidant defense system and, consequently oxidative stress, inflammation and apoptosis-related factors, were all quantified using commercial kits or by western blotting. SEV preconditioning was demonstrated to ameliorate kidney injury as a result of decreased blood urine nitrogen and serum creatinine levels, activated Nrf2 expression in the kidney and decreased oxidative stress and inflammatory index levels an AKI mouse model. SEV preconditioning also protected injured kidney via the downregulation of caspase-3 protein expression levels. In addition, using the Nrf2 inhibitor, Brusatol, significantly abolished the SEV preconditioning renal protective effect. Using an in vitro HK-2 cell model of hypoxia/reoxygenation, it was also demonstrated that Nrf2 pathway activation was necessary for SEV to exert its beneficial effect for tubular cell injury caused by hypoxia/reoxygenation. These results indicated that SEV may protect against renal injury caused by IR via Nrf2 upregulation.

Enhanced Percutaneous Delivery of Methotrexate Using Micelles Prepared with Novel Cationic Amphipathic Material.

BACKGROUND: Methotrexate (MTX) is an antiproliferative drug widely used to treat inflammatory diseases and autoimmune diseases. The application of percutaneous administration is hindered due to its poor transdermal penetration. To reduce side effects and enhanced percutaneous delivery of MTX, novel methotrexate (MTX)-loaded micelles prepared with a amphiphilic cationic material, N,N-dimethyl-(N',N'-di-stearoyl-1-ethyl)1,3-diaminopropane (DMSAP), was designed. MATERIALS AND METHODS: DMSAP was synthesized via three steps using simple chemical agents. H nuclear magnetic resonance and mass spectroscopy were used to confirm the successful synthesis of DMSAP. A safe and non-toxic phosphatidylcholine, soybean phosphatidylcholine (SPC), was added to DMSAP at different ratios to form P/D-micelles. Then, MTX-entrapped micelles (M/P/D-micelles) were prepared by electrostatic adsorption. The physicochemical properties and blood stability of micelles were examined thoroughly. In addition, the transdermal potential of the micelles was evaluated by permeation experiments. RESULTS: In aqueous environments, DMSAP conjugates could self-assemble spontaneously into micelles with a low critical micelle concentration (CMC) of 0.056 mg/mL. Stable, spherical MTX-entrapped micelles (M/P/D-micelles) with a size of 100-120 nm and high zeta potential of +36.26 mV were prepared. In vitro permeation studies showed that M/P/D-micelles exhibited superior skin permeability and deposition of MTX in the epidermis and dermis compared with that of free MTX. CONCLUSION: These special novel cationic M/P/D-micelles can enhance the permeability of MTX and are expected to be a promising percutaneous delivery system for therapy skin diseases.

Efficient delivery of Notch1 siRNA to SKOV3 cells by cationic cholesterol derivative-based liposome.

A novel cationic cholesterol derivative-based small interfering RNA (siRNA) interference strategy was suggested to inhibit Notch1 activation in SKOV3 cells for the gene therapy of ovarian cancer. The cationic cholesterol derivative, N-(cholesterylhemisuccinoyl-amino-3-propyl)-N, N-dimethylamine (DMAPA-chems) liposome, was incubated with siRNA at different nitrogen-to-phosphate ratios to form stabilized, near-spherical siRNA/DMAPA-chems nanoparticles with sizes of 100-200 nm and zeta potentials of 40-50 mV. The siRNA/DMAPA-chems nanoparticles protected siRNA from nuclease degradation in 25% fetal bovine serum. The nanoparticles exhibited high cell uptake and Notch1 gene knockdown efficiency in SKOV3 cells at an nitrogen-to-phosphate ratio of 100 and an siRNA concentration of 50 nM. They also inhibited the growth and promoted the apoptosis of SKOV3 cells. These results may provide the potential for using cationic cholesterol derivatives as efficient nonviral siRNA carriers for the suppression of Notch1 activation in ovarian cancer cells.

A comparison between conventional liposome and drug-cyclodextrin complex in liposome system.

A drug-cyclodextrin complex in liposome system was prepared in order to make a comparison with conventional risperidone-loaded liposome. Thin film hydration, reverse phase evaporation and ethanol injection methods were taken as preparation means to obtain the two types of liposome. Differential thermal analysis (DTA) and transmission electron microscopy (TEM) were used to investigate the thermal characters of inclusion complexes and morphology of liposome, respectively. Particle size, zeta potential and encapsulation efficiency were studied by light scattering analysis and ultrafiltration. In vitro release was carried out in the pH 7.4 phosphate buffer solution and samples were collected at the certain time. As a result, drug-cyclodextrin complex in liposome prepared by various methods displayed lower encapsulation efficiency than conventional liposome. However, size was larger and its stability was better than the latter. The second release phase of novel delivery system was slightly slower after initial burst release at the first phase, while the conventional liposome displayed a more regular trait. Thus, the novel liposome have potential to be developed as co-administration formulation with long-acting injection.

[The strategies of endosomal escape for intracellular gene delivery].

The intracellular trafficking and subcellular distribution of exogenous gene is very important for gene delivery. A successful gene vehicle should overcome various barriers including endosomal membrane barriers to delivery gene to the target organelle. Traditional nonviral vehicle is unable to avoid endosomal pathway efficiently, so the efficiency of gene delivery is low and the application of gene drugs is limited. In order to achieve efficient nonviral gene delivery, a lot of researches based on endosomal escape have been carried out and some agents with the function of endsomal escape have been found. These agents facilitate the endsomal escape via various mechanisms, such as fusion into the lipid bilayer of endosomes, pore formation in the endosomal membrane, proton sponge effect and photochemical methods to rupture the endosomal membrane. In this review, various reported strategies for endsomal escape are described according to the escape mechanisms, and their applications in intracellular gene delivery are also discussed.

Enhanced antitumor efficacy with combined administration of astragalus and pterostilbene for melanoma.

Astragalus, a commonly used traditional Chinese medicine, has exhibited antitumor actions in patients. In this study, in vitro and in vivo antitumor effects of astragalus and synergistic antitumor efficacy in combination with pterostilbene were investigated. Melanoma cells were treated with pterostilbene (Pt), graduated doses of astragalus injection (AI), or these in combination. Cell viability was measured using a MTT assay. Released nucleosomes and caspase activity were measured using enzyme-linked immunosorbent assay. Growth inhibition in vitro and in vivo was also assessed. Analysis of variance and t tests were used for statistical analysis. Significant reduction (p<0.05) in cellular proliferation were observed with AI and AI-Pt in a time- and concentration-dependent manner. Apoptosis and caspase-3/7 activity were significantly increased by AI and AI-Pt treatment (p<0.05). In vivo, AI inhibited melanoma tumor growth, with inhibition rates ranging from 36.5 to 62.3%, by inducing apoptosis via up-regulation Bax expression and the Bax/Bcl-2 ratio and down-regulating Bcl-2 expression. AI significantly inhibits the growth of melanoma in vitro and in vivo by inducing apoptosis. These data suggest that combined treatment of astragalus with pterostilbene enhances antitumor efficacy.

2-Hy-droxy-ethanaminium 2-methyl-5-nitro-benzene-sulfonate.

In the crystal structure of the title salt, C(2)H(8)NO(+)·C(7)H(6)NO(5)S(-), the cations and anions are linked together by N-H⋯O and O-H⋯O hydrogen bonds, forming layers parallel to (100). The plane of nitro group is skew with respect to the plane of benzene ring, making a dihedral angle of 17.5 (2)°.

Chitosan-coated liposomes for intracellular oligonucleotides delivery: characteristics and cell uptake behavior.

Surface modification of liposomes with polymer to optimize drug delivery was well developed recently. The objective of the present work was to evaluate the feasibility of chitosan-coated liposomes (CSLP) as vehicles for anti-sense oligodeoxynucleotides (ASON). CSLP was obtained by adding chitosan dropwise to liposomes under magnetic stirring. The effect of chitosan content on size, zeta potential, and coating efficiency was investigated, which showed that chitosan increased the size and zeta potential of CSLP, and the coating efficiency increased with chitosan content increasing. Agarose gel electrophoresis was employed to evaluate the loading efficiency of CSLP for ASON, from which one could see ASON was completely combined to CSLP when the mass ratio of total lipids:ASON was more than 50:1. MTT assay showed that CSLP took on very low cytotoxicity, which is much lower than chitosan. At last, cell uptake behavior was investigated by a flow cytometer, which showed that CSLP enhanced significantly the COS7 cells uptake of ASON. All the results indicated that the CSLP could be a promising non-viral ASON vehicle.

[Significance of glomerular filtration rate in evaluating renal function of comparative study of methods thereof].

OBJECTIVE: To evaluate the applicability of the Cockcroft-Gault equation and the abbreviated Modification of diet in Renal Disease (MDRD) study equation to estimate the renal function of diabetic patients. METHODS: Glomerular filtration rates measured by these two equations were compared with the value of GFR measured by 99Tc(m)-DTPA dynamic renal Imaging (considered as gold standard), to determine which equation is more appropriate in the subjects with diabetes. RESULTS: Both of the results of the two equations deviated from the GFR measured by 99Tc(m)-DTPA dynamic renal Imaging: the GFRCG result was lower and the GFR(MDRD) result was higher than the real GFR value. However, the correlation analysis, coherence testing, and accuracy by receiver operating characteristic curve analysis showed that the coefficient of correlation, coherence rate, and accuracy of the GFR(MDRD) formula with the gold standard were all higher than those of the GFR(CG) formula. CONCLUSION: The abbreviated style of MDRD equation is more appropriate than Cockcroft-Gault equation for the estimating of renal function in diabetic patients.

[Cellular uptake behavior of antisense oligodeoxynucleotides polymethacrylate submicroparticles].

AIM: To survey the uptake behavior and subcellular distribution of antisense oligodeoxynucleotide polymethacrylate submicroparticles (AS-ODN-SMP) and infer its mechanism in MGC cell lines. METHODS: MGC cells were incubated at certain concentration of AS-ODN-SMP or AS-ODN for 8 h at 4 degrees C or 37 degrees C. Then the fluorescence oligodeoxynucleotide- labeled cells were counted by flow cytometer and the intracellular fluorescence intensity was determined after incubated with chloroquine for 2 h. RESULTS: Cellular uptake of oligodeoxynucleotides was significantly increased following application of AS-ODN-SMP and total intracellular fluorescence intensity was enhanced by 683 folds with the vehicle concentration of 20 microg x mL(-1). AS-ODN-SMP entranced to cells profoundly with temperature-dependent manner. Rare cells took on fluorescence when incubated at 4 degrees C, while 37 degrees C they were significantly increased. But the intracellular fluorescence intensity appeared same level in present or absent of chloroquine. CONCLUSION: With the help of polyacrylate submicroparticles, oligonucleotides efficiently entranced the cells via endocytosis and could successfully escape the degradation in lysosome.

[Effect of panaxadiol saponin and panaxtrol saponin on proliferation of human bone marrow hemopoietic progenitor cells].

OBJECTIVE: To observe the effect of panaxadiol saponin (PDS) and panaxtrol saponin (PTS) on proliferation of human bone marrow hemopoietic progenitor cells (HPC). METHODS: PDS and PTS were separated and purified from ginsenosides, and the effects on HPC were studied using in vitro hemopoietic progenitor cell colony-forming technique, by observing the proliferation of human burst forming unit-erythroid progenitor (BFU-E), colony-forming unit-erythroid (CFU-E), colony-forming unit-granulocyte/macrophage (CFU-GM) and colony-forming unit-pluripotent hemopoietic progenitor (CFU-Mix) in mice after PDS and PTS stimulation. RESULTS: Different concentration of PDS (2.5-200 micrograms/ml) could stimulate the proliferation of HPC obviously, showing increase of CFU-E, BFU-E, CFU-GM and CFU-Mix by 54.9 +/- 6.3%, 48.8 +/- 5.1%, 27.6 +/- 4.2% and 48.9 +/- 3.9% respectively, which was higher than that of the control group. While stimulated by PTS of the same concentration, the CFU-E and BFU-E was lower than that of control significantly (P < 0.05); when the terminal concentration of PTS was 200 micrograms/ml, CFU-E and BFU-E was zero respectively. In the CFU-GM culture, PTS in concentration of 12.5 micrograms/ml could cause the proliferation increased by 29.7 +/- 2.2% (P < 0.05), but in concentration of 100 micrograms/ml and 200 micrograms/ml, it showed inhibitory effect on CFU-GM, the inhibition rate being 48.6 +/- 3.9% and 100% respectively. CONCLUSION: PDS is the effective component of ginsenosides in stimulating proliferation of human bone marrow HPC. PTS is an component with inhibitory action on proliferation of CFU-E and BFU-E and its effect on CFU-GM was depending on its concentration.

Use of the Endo-GIA vascular stapler for hepatic resection.

OBJECTIVE: The aim of this study was to analyse the outcome of hepatectomy using the Endo-GIA vascular stapler and to derive a strategy to avoid complications from its use. METHODS: From October 1998 to December 2001, 156 patients underwent major hepatectomy for hepatocellular carcinoma. There were 124 men and 32 women, with a median age of 52.5 years. The Endo-GIA vascular stapler was used for division of the hepatic vein and hepatic duct. Intra- and postoperative clinical data were evaluated. RESULTS: The overall morbidity and mortality rates were 32.1% and 8.3%, respectively. Seventy-six percent of patients did not require blood transfusion. The median blood loss volume was 1 L. There were no complications related to the use of the Endo-GIA vascular stapler in dividing the hepatic veins. One patient (0.6%) had a complication from the use of the stapler for right hepatic duct transection and recovered uneventfully after hepaticojejunostomy. Intraoperative cholangiography was performed in subsequent patients undergoing right trisegmentectomy to avoid biliary complications. CONCLUSIONS: The Endo-GIA vascular stapler is a safe and useful tool to divide the hepatic vein, but surgeons should exercise particular caution to avoid complications when it is used for hepatic duct division.

[Study on polymethacrylate nanoparticles as delivery system of antisense oligodeoxynucleotides].

AIM: To investigate the possibility of polymethacrylate nanoparticles (NP) for antisense oligodeoxynucleotides delivery system. METHODS: The nanoparticles were prepared by evaporating ethenol solution containing Eudragit RL100 or RS100, and then mixtured with oligonucleotides. The morphology and size were investigated by a transmission electron microscope and Mastersizer particle characterization systems, and the cytotoxicity was evaluated by Trypan Blue staining and hemolysis test. The flow cytometer was used to determine the uptake of fluorescence-labelled oligodeoxynucleotides. RESULTS: The morphology of nanoparticles showed spherical and orderly, the average diameter was about 127 nm, and almost the antisense oligodeoxynucleotides (ODN) were loaded when NP: ODN was 6.6. The uptake of ODN was significantly increased when loaded by nanoparticles, which well depended on the nanoparticles concentration. Meanwhile, slightly cytotoxicity was observed when high dose of nanoparticles was used. CONCLUSION: The polymethacrylate nanoparticles appeared to be a promising vehicle for gene delivery.

Safety and necessity of including the middle hepatic vein in the right lobe graft in adult-to-adult live donor liver transplantation.

OBJECTIVE: To evaluate the safety of donors who have donated the middle hepatic vein in right lobe live donor liver transplantation (LDLT) and to determine whether such inclusion is necessary for optimum graft function. SUMMARY BACKGROUND DATA: The necessity to include the middle hepatic vein in a right lobe graft in adult-to-adult LDLT is controversial. Inclusion of the middle hepatic vein in the graft provides uniform hepatic venous drainage but may lead to congestion of segment IV in the donor. METHODS: From 1996 to 2002, 93 right-lobe LDLTs were performed. All right-lobe grafts except 1 contained the middle hepatic vein. In the donor operation, attention was paid to preserve the segment IV hepatic artery and to avoid prolonged rotation of the right lobe. The middle hepatic vein was transected proximal to a major segment IVb hepatic vein whereas possible to preserve the venous drainage in the liver remnant. RESULTS: There was no donor death. Two donors had intraoperative complications (accidental left hepatic vein occlusion and portal vein thrombosis) and were well after immediate rectification. Twenty-four donors (26%) had postoperative complications, mostly minor wound infection. The postoperative international normalized ratio on day 1 was better in the donors with preservation of segment IVb hepatic vein than those without the preservation, but, in all donors, the liver function was largely normal by postoperative day 7. The first recipient had severe graft congestion as the middle hepatic vein was not reconstructed before reperfusion. In 7 other recipients, the middle hepatic vein was found occluded intraoperatively owing to technical errors. The postoperative hepatic and renal function of the recipients with an occluded or absent middle hepatic vein was worse than those with a patent middle hepatic vein. The hospital mortality rate was also higher in those with an occluded middle hepatic vein (3/9 vs. 5/84, P = 0.028). CONCLUSIONS: Inclusion of the middle hepatic vein in right-lobe LDLT is safe and is essential for optimum graft function and patient survival.

Live donor liver transplantation in adults: graft size, related anatomical anomaly and imaging evaluation of donor.

The shortage of cadaveric livers has sparked an interest in adult live donor liver transplantation. Right lobe donor hepatectomy is frequently required to obtain a graft of adequate size for adult recipients. This procedure requires not only a precise understanding of liver anatomy and anatomic anomaly, but also the means of assessing them. This review focuses on the key points in adult live donor liver transplantation using the right lobe combined with our own experience in 81 cases including graft size, related anatomical anomaly and imaging evaluation of donor.