Ferulic acid (FA) was loaded into liposomes via calcium acetate gradient with (80.2 +/- 5.2)% entrapment efficiency. The average sizes of blank liposome and FA liposome were about 155 nm and 154 nm, respectively. The zeta potential of blank liposome and FA liposome were (13.14 +/- 1.67) mV and (4.12 +/- 0.05) mV, respectively. Unilamellar vesicles were present in freeze-fracture electron microscopy. In the pharmacodynamic studies, the protective effect of liposomal ferulic acid on tBHP-challenged U937 cells was measured with the morphology of cell injury, mitochondrial transmembrane potential alternation and cell viability assay used as index. The results of MTT assay, microscopy indicated that FA liposomes exhibited greater antioxidant activity than FA solution on U937 cell.
Antioxidants ; administration & dosage ; pharmacology ; Cholesterol ; chemistry ; Coumaric Acids ; administration & dosage ; pharmacology ; Drug Carriers ; Humans ; Liposomes ; chemistry ; Membrane Potentials ; drug effects ; Mitochondria ; physiology ; Particle Size ; U937 Cells

pH and temperature sensitive biodegradable block copolymers are some macromolecules connected by biodegradable materials and pH sensitive monomers according to a certain sequence, or biodegradable polyesters polymerized themselves. On the basis of pertinent documents, the development of pH and temperature sensitive biodegradable block copolymers was introduced, involving their mechanism of action and potential application. PH and temperature sensitive biodegradable block copolymers could control the drug release rate freely, avoiding burst effect. Besides, the biocompatibility of these biodegradable materials is also excellent. So the use of pH and temperature sensitive biodegradable block copolymers as biodegradable drug delivery devices has attracted considerable interest in the intelligent drug delivery system.
Biocompatible Materials ; chemistry ; Drug Delivery Systems ; Hydrogen-Ion Concentration ; Lactates ; chemistry ; Lactic Acid ; chemistry ; Polyesters ; chemistry ; Polyethylene Glycols ; chemistry ; Polyglactin 910 ; chemistry ; Polyglycolic Acid ; chemistry ; Polymers ; chemistry ; Temperature

We reported a case of multiple type II endoleaks detected by duplex ultrasound after endovascular abdominal aneurysm repair. The patient was undergoing warfarin therapy. Duplex ultrasound was applied as the sole surveillance method during follow-up and provided the concerned information for reintervention. The endoleaks were successfully repaired by coil embolization of the collaterals from the internal iliac artery feeding the fourth lumbar artery.
Aortic Aneurysm, Abdominal ; diagnostic imaging ; Female ; Humans ; Middle Aged ; Ultrasonography, Doppler, Duplex ; methods

BACKGROUNDIntravascular ultrasound (IVUS) examination can provide useful information during endovascular stent graft repair. However, its actual clinical utility in thoracic endovascular aortic repair (TEVAR) for type B aortic dissection (type B-AD) remains unclear, especially in complicated aortic dissection. We evaluated the effect of IVUS as a complementary tool during TEVAR.

METHODSFrom September 2011 to April 2012, we conducted a prospective cohort study of 47 consecutive patients with "complicated" type B-AD diagnosed. We divided the patients into two groups: IVUS-assisted TEVAR group and TEVAR using angiography alone group. The general procedure of TEVAR was performed. We evaluated the perioperative and follow-up events. Patient demographics, comorbidities, preoperative images, dissection morphology, details of operative strategy, intraoperative events, and postoperative course were recorded.

RESULTSA total of 47 patients receiving TEVAR were enrolled. Among them (females, 8.51%; mean age, 57.38 ± 13.02 years), 13 cases (27.66%) were selected in the IVUS-assisted TEVAR group, and 34 were selected in the TEVAR group. All patients were symptomatic. The average diameter values of IVUS measurements in the landing zone were greater than those estimated by computed tomography angiography (31.82 ± 4.21 mm vs. 30.64 ± 4.13 mm, P < 0.001). The technique success rate was 100%. Among the postoperative outcomes, statistical differences were only observed between the IVUS-assisted TEVAR group and TEVAR group for total operative time and the amount of contrast used (P = 0.013 and P < 0.001, respectively). The follow-up ranged from 15 to 36 months for the IVUS-assisted TEVAR group and from 10 to 35 months for the TEVAR group (P = 0.646). The primary endpoints were no statistical difference in the two groups.

CONCLUSIONSIntraoperative IVUS-assisted TEVAR is clinically feasible and safe. For the endovascular repair of "complicated" type B-AD, IVUS may be helpful for understanding dissection morphology and decrease the operative time and the amount of contrast used.

Adult ; Aged ; Aneurysm, Dissecting ; surgery ; Aorta, Thoracic ; surgery ; Aortic Aneurysm, Thoracic ; surgery ; Female ; Humans ; Male ; Middle Aged ; Prospective Studies ; Stents

OBJECTIVETo prepare the long-circulating nanoliposomes of curcumin.

METHODThe long-circulating nanoliposomes were prepared by ethanol infusion and the encapsulation efficiency was determindated by the mini-column centrifugation. The effect of some factors on the encapsulation efficiency, such as the buffer solutions, the weight ratio of curcumin to SPC, the weight ratio of SPC to Chol, the pH of buffer solution and the iron strength of water phase, was investigated respectively. Then the formulation was optimized by orthogonal design.

RESULTThe encapsulation efficiency of the curcumin liposomes was (88.27 +/- 2.16)%, and the average diameter of the liposomes was (136 +/- 18) nm. There was no change on encapsulation efficency within 30 d.

CONCLUSIONThe preparation of curcumin liposomes was easy and practicable and the pharmaceutical characterization showed that the curcumin liposomes are stable.

Chemistry, Pharmaceutical ; Curcumin ; administration & dosage ; chemistry ; Drug Prescriptions ; Drugs, Chinese Herbal ; administration & dosage ; chemistry ; Hydrogen-Ion Concentration ; Liposomes ; blood ; chemistry ; Molecular Weight ; Nanostructures ; analysis ; Particle Size ; Sodium Chloride ; chemistry

Objective: To investigate the growth inhibition and apoptosis induction effect of vitamin E succinate (VES) on human colon cancer cells and to analyze the modulation of apoptosis-mediator Fas expression in this process. Methods: Human colon cancer cell line LS174T was treated with VES for 12 h, 24 h and 48 h at the concentrations of 5 mg/L, 10 mg/L and 20mg/L. 1-(4,5-dimethylthiazo-2-yl)-3,5-diphenylformazan (MTT) assay was employed to detect the inhibitory effect of VES on the growth of colon cancer cells. Flow cytometry was then used to analyze the cell cycle of the colon cancer cells after being treated with VES and the apoptotic rate was calculated at the same time. To find out whether the Fas protein expression was modulated in this process, Western blotting assay and flow cytometry were used to detect the Fas protein level in whole cell lystates and on cell surface. Results: VES exhibited a significant inhibitory effect on the growth of human colon cancer cells in a doseand time-dependent manner. After being treated with VES at 5 mg/L, 10 mg/L and 20 mg/L for 48 h, the apoptotic rate of LS174T cells rose from 0.90% to 15.9%, 46.7% and 64.5%, respectively. Fas neutralizing antibody can significantly block VES-induced apoptosis. After the administration of VES, total Fas protein in whole-cell extracts increased in a dose-dependent manner. The flow cytometry showed that the mean fluorescence intensity rose from 5.43 to 9.88, 13.21 and 18.0 after being treated with VES. Conclusion: VES can induce significant growth inhibition and apoptosis in human colon cancer cells. The modulation of Fas expression is one of the mechanisms involved in this process and may be related to the upregulation of Fas molecule on the cancer cell surface.

OBJECTIVETo evaluate the role of intravascular ultrasound (IVUS) imaging in the diagnosis of aortic dissection.

METHODSEighty-two patients with aortic dissection were admitted. The role of IVUS was evaluated and compared with CT, MRI, transthoracic echocardiography (TTE), transesophageal echocardiography (TEE), Duplex scanning and digital subtraction angiography (DSA).

RESULTSThe different laminar appearance of the outer wall of the true and false lumen, characteristic alterations in the true and false lumen junction and the thrombosis in the false lumen detected by IVUS were useful to differentiate the true from the false lumen. Static and dynamic narrowing, causing visceral ischemia could be detected by IVUS imaging. The detection rate of entry site by IVUS was 100%, higher than CT (28%), MRI (22%), TTE (2%) and TEE (61%), P < 0.01, having no statistic difference with DSA (88%). The detection rate of the distal end of the dissection by IVUS was 100%, higher than Duplex (21%), P < 0.01, but had no statistic difference as compared with CT (89%) and MRI (86%). The detection rate of visceral arteries by IVUS was 98%, higher than CT (56%), MRI (57%), Duplex (17%) and DSA (66%), P < 0.01. The aortic diameter measured by IVUS was correlated well with CT measurement (r = 0.94, P < 0.01).

CONCLUSIONSA full picture of aortic dissection can be obtained using IVUS imaging. It has an advantage over routine examinations in detecting visceral artery origin and clarifying visceral ischemia causes.

Adult ; Aged ; Aneurysm, Dissecting ; diagnostic imaging ; Aorta ; diagnostic imaging ; Aortic Aneurysm ; diagnostic imaging ; Female ; Humans ; Male ; Middle Aged ; Ultrasonography, Interventional

Recently the use of peptides in bee venom (PBV) for cancer therapy has attracted considerable attention. In this study, the sterically stabilized liposomal PBV (PBV-SL) was prepared using soybean phosphatidylcholine, cholesterol, and cholesterol-PEG-COOH. The humanized antihepatoma disulfide-stabilized Fv (hdscFv25) was coupled to sterically stabilized liposomes using the N-hydroxysuccinimide ester method. The hdscFv25-immunoliposomes (SIL[hdscFv25]) were immunoreactive as determined by ELISA assay. SIL[hdscFv25] showed higher tumor cells selectivity. PBV-SIL[hdscFv25] can kill SMMC-7721 cells in vitro with higher efficiency than non-targeted liposomes. Whereas cytotoxicties were compared for Hela cells, no significant differences was observed between PBV-SIL[hdscFv25] and PBV-SL. Sterically stabilized immunoliposomal peptides in bee venom could be one drug targeting delivery system.
Antineoplastic Agents ; administration & dosage ; pharmacology ; Bee Venoms ; chemistry ; Carcinoma, Hepatocellular ; pathology ; Cell Line, Tumor ; Cell Survival ; drug effects ; Cholesterol ; chemistry ; Drug Delivery Systems ; HeLa Cells ; Humans ; Immunoconjugates ; chemistry ; pharmacology ; Liposomes ; chemistry ; Liver Neoplasms ; pathology ; Melitten ; administration & dosage ; isolation & purification ; pharmacology ; Peptides ; administration & dosage ; isolation & purification ; pharmacology ; Recombinant Proteins ; administration & dosage ; pharmacology

Dendrimers are hyperbranched, monodisperse and three dimensional macromolecules, which consist of an apolar core and polar shell have been referred to as "unimolecular micelles". This paper briefly describes the development and structural characteristics of dendrimers and also explains the feature of dendrimers as drug carrier and the dendrimer-drug interactions in details. Recently, dendrimers, which have attracted increasing attention for their applications in many fields such as drug targeted delivery systems and gene transfection, are becoming potential novel carriers.
Dendrimers ; chemistry ; Drug Delivery Systems ; Drug Design ; Polyamines ; chemistry

In this study, wheat germ agglutinin (WGA), tomato lectin (TL) and asparagus pea lectin (AL) were covalently coupled to conventional poly lactic-co-glycolic acid (PLGA) nanoparticles using a carbodiimide method to take the bioadhesive properties. The influences of the amounts of activating agents and lectins, as well as the activating time and incubating time on the effect of lectin conjugating were investigated to optimize the preparation conditions. The mean diameters of the performed nanoparticles with or without lectin conjugation ranged from (140.7 +/- 5.7) nm to (245.6 +/- 18.3) nm. The yields of lectin conjugating and the lectin surface concentrations on nanoparticles were determined by Lowry's methods, and were calculated to be (18.97 +/- 2.9)% - (20.15 +/- 2.4)% and (9.46 +/- 1.45)--(10.05 +/- 1.19) microg x mg(-1), respectively. The in vitro bioadhesive activities of nanoparticles were evaluated by pig gastric mucin (PM) binding experiments. After incubation at room temperature for 60 min, the equilibria of binding between nanoparticles and PM reached. The percentages of the bulk PM which had interacted with different lectin-conjugated PLGA nanoparticles were 15.5%, 12.1% and 11.8%, respectively. The conjugation of lectin enhanced the interaction about 2.4 - 3.2 fold compared with that of the non-conjugated one. A mathematical model was used based on the Langmuir equation, and the rate constants of interaction (k) were calculated to be 2.373 x 10(-3), 1.536 x 10(-3) and 1.714 x 10(-3) (microg x min/mL)(-1), respectively. These interactions could be competitively inhibited by their corresponding sugars of lectins. The results suggested that lectin-conjugated PLGA nanoparticles greatly promoted the interaction with PM in vitro compared with the conventional PLGA nanoparticles, thus would improve the bioadhesion on gastrointestinal mucosa after oral administration resulting in a prolonged residence time in the gastrointestinal tract.
Adhesiveness ; Drug Carriers ; Drug Compounding ; Drug Delivery Systems ; Gastric Mucins ; metabolism ; Lactic Acid ; chemistry ; metabolism ; Nanoparticles ; Plant Lectins ; chemistry ; metabolism ; Polyglycolic Acid ; chemistry ; metabolism ; Protein Binding ; Wheat Germ Agglutinins ; chemistry ; metabolism