Construction of Functional Targeting Daunorubicin Liposomes Used for Eliminating Brain Glioma and Glioma Stem Cells.

The highly infiltrative nature of brain glioma makes total surgical removal of cancerous cells virtually impossible. Regular chemotherapy plays an important role in eradicating the residual cancer cells but is ineffective in treating brain glioma due to the hindrance of drug penetration into the tumor site by the blood brain barrier (BBB) and the regeneration of cancer cells by glioma stem cells (GSCs). In this study, functional targeting daunorubicin liposomes were developed by modifying the liposomes with distearoylphosphatidylethanolamine polyethylene glycol-polyethylenimine (DSPE-PEG2000PEI600 and a lipid-glucose derivative (DSPE-PEG2000-GLU). The studies were performed in brain glioma and glioma stem cells in vitro and in brain glioma-bearing mice inoculated with the glioma stem cells. The results showed that the functional targeting daunorubicin liposomes were able to significantly transfer across the BBB and exhibited an obvious efficacy in killing glioma and glioma stem cells in mice. The action mechanisms of the functional targeting daunorubicin liposomes were related to their properties: long-duration circulation in the blood system, transport capability across the BBB, concentrated accumulation in the brain glioma site, and increased internalization by malignant cells and their mitochondria. This functional drug formulation showed anticancer efficacy through a direct cytotoxic effect and an apoptosis-inducing effect through the apoptotic signaling pathways in the cytoplasm and mitochondria of the cells. As a chemotherapy strategy for treating brain glioma, functional targeting daunorubicin liposomes have the potential to eliminate brain glioma along with glioma stem cells.

A nanostructure of functional targeting epirubicin liposomes dually modified with aminophenyl glucose and cyclic pentapeptide used for brain glioblastoma treatment.

The objectives of the present study were to develop functional targeting epirubicin liposomes for transferring drugs across the blood-brain barrier (BBB), treating glioblastoma, and disabling neovascularization. The studies were performed on glioblastoma cells in vitro and on glioblastoma-bearing mice. The results showed that the constructed liposomes had a high encapsulation efficiency for drugs (>95%), suitable particle size (109 nm), and less leakage in the blood component-containing system; were significantly able to be transported across the BBB; and exhibited efficacies in killing glioblastoma cells and in destroying glioblastoma neovasculature in vitro and in glioblastoma-bearing mice. The action mechanisms of functional targeting epirubicin liposomes correlated with the following features: the long circulation in the blood system, the ability to be transported across the BBB via glucose transporter-1, and the targeting effects on glioblastoma cells and on the endothelial cells of the glioblastoma neovasculature via the integrin ß3 receptor. In conclusion, functional targeting epirubicin liposomes could be used as a potential therapy for treating brain glioblastoma and disabling neovascularization in brain glioblastomas.

Multifunctional targeting daunorubicin plus quinacrine liposomes, modified by wheat germ agglutinin and tamoxifen, for treating brain glioma and glioma stem cells.

Most anticancer drugs are not able to cross the blood-brain barrier (BBB) effectively while surgery and radiation therapy cannot eradicate brain glioma cells and glioma stem cells (GSCs), hence resulting in poor prognosis with high recurrence rates. In the present study, a kind of multifunctional targeting daunorubicin plus quinacrine liposomes was developed for treating brain glioma and GSCs. Evaluations were performed on in-vitro BBB model, murine glioma cells, GSCs, and GSCs bearing mice. Results showed that the multifunctional targeting daunorubicin plus quinacrine liposomes exhibited evident capabilities in crossing the BBB, in killing glioma cells and GSCs and in diminishing brain glioma in mice. Action mechanism studies indicated that the enhanced efficacy of the multifunctional targeting drugs-loaded liposomes could be due to the following aspects: evading the rapid elimination from blood circulation; crossing the BBB effectively; improving drug uptake by glioma cells and GSCs; down-regulating the overexpressed ABC transporters; inducing apoptosis of GSCs via up-regulating apoptotic receptor/ligand (Fas/Fasl), activating apoptotic enzymes (caspases 8, 9 and 3), activating pro-apoptotic proteins (Bax and Bok), activating tumor suppressor protein (P53) and suppressing anti-apoptotic proteins (Bcl-2 and Mcl-1). In conclusion, the multifunctional targeting daunorubicin plus quinacrine liposomes could be used as a potential therapy for treating brain glioma and GSCs.

Liposomes, modified with PTD(HIV-1) peptide, containing epirubicin and celecoxib, to target vasculogenic mimicry channels in invasive breast cancer.

Refractoriness of invasive breast cancer is closely related with the vasculogenic mimicry (VM) channels, which exhibit highly drug resistance to conventional chemotherapies. In the present study, the nanostructured targeting epirubicin plus celecoxib liposomes were developed by modifying a human immunodeficiency virus peptide lipid-derivative conjugate (DSPE-PEG2000-PTDHIV-1) for elimination of invasive breast cancer cells along with their VM channels. The studies were undertaken on invasive human breast cancer MDA-MB-435S cells and MDA-MB-435S xenografts in nude mice. The constructed targeting epirubicin plus celecoxib liposomes were approximately 100 nm in size. In vitro results showed that the targeting liposomes exhibited strong transport ability across cell and nuclei membranes of invasive breast cancer, were able to penetrate and destruct the invasive breast cancer spheroids, initiated apoptosis via activating apoptotic enzymes (caspase 8, 3), and destroyed the VM channels via down-regulating the protein indicators (MMP-9, VE-Cad, FAK, EphA2 and HIF-1α) in invasive breast cancer cells. In vivo results demonstrated that the targeting liposomes displayed a prolonged circulation time in blood system, accumulated more in tumor location, were able to eliminate the VM channels and angiogenesis in tumor tissues, and resulted in a robust overall anticancer efficacy in invasive breast cancer MDA-MB-435S xenografts in nude mice. In conclusion, the nanostructured targeting epirubicin plus celecoxib liposomes could eliminate invasive breast cancer along with the VM channels, hence providing a promising strategy for treatment of invasive breast cancer.

Multifunctional liposomes loaded with paclitaxel and artemether for treatment of invasive brain glioma.

Invasive brain glioma is the most lethal type of cancer and is highly infiltrating. This leads to an extremely poor prognosis and makes complete surgical removal of the tumor virtually impossible. Non-penetration of therapeutic drugs across the blood-brain barrier (BBB), brain cancer stem cells (CSCs), and brain cancer vasculogenic mimicry (VM) results in relapse after surgical and radio therapy. We developed a functional targeting chemotherapy for transporting drugs across the BBB, destroying VM channels, and eliminating CSCs and cancer cells in the brain. The studies were undertaken on brain glioma cells in vitro and in brain glioma-bearing rats. Using paclitaxel as the anticancer drug and artemether as the regulator of apoptosis and inhibitor of VM channels, a kind of functional targeting paclitaxel plus artemether liposomes was developed by modifying two new functional materials: a mannose-vitamin E derivative conjugate (MAN-TPGS1000) and a dequalinium-lipid derivative conjugate (DQA-PEG2000-DSPE). The transport mechanism across the BBB was associated with receptor-mediated endocytosis by MAN-TPGS1000 conjugate via glucose transporters and adsorptive-mediated endocytosis by DQA-PEG2000-DSPE conjugate via electric charge-based interactions. The efficacy was related to the destruction of VM channels by regulating VM indicators, as well as the induction of apoptosis in brain cancer cells and CSCs by activating apoptotic enzymes and pro-apoptotic proteins and inhibiting anti-apoptotic proteins. These data suggest that the chemotherapy using functional targeting paclitaxel plus artemether liposomes could provide a new strategy for treating invasive brain glioma.

Modulation of drug-resistant membrane and apoptosis proteins of breast cancer stem cells by targeting berberine liposomes.

The recurrence of breast cancer is associated with drug-resistance of cancer stem cells (CSCs), while overexpression of cell membrane ATP-binding cassette (ABC) transporters and resistance of mitochondrial apoptosis-related proteins are responsible for the drug-resistance of CSCs. The targeting berberine liposomes were developed to modulate the resistant membrane and mitochondrial proteins of breast CSCs for the treatment and prevention of breast cancer relapse. Evaluations were performed on human breast CSCs and CSC xenografts in nude mice. The targeting berberine liposomes were shown to cross the CSC membrane, inhibit ABC transporters (ABCC1, ABCC2, ABCC3, ABCG2) and selectively accumulate in the mitochondria. Furthermore, the pro-apoptotic protein Bax was activated while the anti-apoptotic protein Bcl-2 was inhibited resulting in opening of the mitochondrial permeability transition pores, release of cytochrome c, and activation of caspase-9/caspase-3 enzymes. Significant efficacy of the administrations in mice was observed, indicating that the targeting berberine liposomes are a potential therapy for the treatment and prevention of breast cancer relapse arising from CSCs.

Development of targeting lonidamine liposomes that circumvent drug-resistant cancer by acting on mitochondrial signaling pathways.

Even when faced with elimination, functional materials may offer new alternatives to expensive drugs. Once used to treat benign prostate hypertrophy, the US Food and Drug Administration (FDA) suspended the use of lonidamine due to the occurrence of liver problems arising from its poor pharmaceutical properties. The objectives of the present study were to develop targeting lonidamine liposomes in combination with targeting epirubicin liposomes to circumvent drug-resistant cancer. Evaluations were performed on A549 and drug-resistant A549cDDP lung cancer cells and drug-resistant A549cDDP xenografted BALB/c nude mice. A DQA-PEG(2000)-DSPE conjugate was incorporated onto the liposomes as a targeting molecule. The constructed targeting lonidamine liposomes and targeting epirubicin liposomes measured were approximately 80 nm. The targeting lonidamine liposomes significantly enhanced the inhibitory effect of the targeting epirubicin liposomes in the drug-resistant A549cDDP cells in a lonidamine dose-dependent manner. Mechanism studies revealed that the targeting liposomes were selectively accumulated in the mitochondria, dissipating the mitochondrial membrane potential, opening the mitochondrial permeability transition pores, and releasing cytochrome C by translocation. This initiated a cascade of caspase 9 and 3 reactions and activated the pro-apoptotic Bax protein while suppressing the anti-apoptotic Mcl-1 protein, thereby enhancing the cytotoxic effect by acting on the mitochondrial signaling pathways. The efficacy in treating the drug-resistant A549cDDP xenografted tumor model after administration of the targeting lonidamine liposomes plus targeting epirubicin liposomes was the most significant compared with the administration of the controls at comparable doses. In conclusion, targeting lonidamine liposomes could be used as a potent co-therapy with an anticancer agent to enhance the efficacy of treating drug-resistant cancer by acting on the mitochondrial signaling pathways.

The anticancer efficacy of paclitaxel liposomes modified with mitochondrial targeting conjugate in resistant lung cancer.

Lung cancer is the leading cause of cancer-related death in humans and the multidrug resistance (MDR) is the major obstacle to successful chemotherapy of lung cancer. In this study, a d-α-tocopheryl polyethylene glycol 1000 succinate-triphenylphosphine conjugate (TPGS1000-TPP) was synthesized as the mitochondrial targeting molecule, and was incorporated onto the surface of paclitaxel liposomes to treat the drug-resistant lung cancer. Evaluations were performed on the human lung cancer A549 cells, the drug-resistant lung cancer A549/cDDP cells, and the drug-resistant lung cancer A549/cDDP cells xenografted nude mice. The yield of TPGS1000-TPP conjugate synthesized was about 50% and the particle size of targeting paclitaxel liposomes developed was approximately 80 nm. In comparison with taxol and regular paclitaxel liposomes, the targeting paclitaxel liposomes exhibited the strongest anticancer efficacy in vitro and in the drug-resistant A549/cDDP xenografted tumor model. The targeting paclitaxel liposomes could significantly enhance the cellular uptake, be selectively accumulated into the mitochondria, and cause the release of cytochrome C. This targeting delivery of drug initiated a cascade of caspase 9 and 3 reactions, activated the pro-apoptotic Bax and Bid proteins and suppressed the anti-apoptotic Bcl-2 protein, thereby enhancing the apoptosis by acting on the mitochondrial signaling pathways. In conclusion, the targeting paclitaxel liposomes have the potential to treat drug-resistant lung cancer.

Perceptual pitch deficits coexist with pitch production difficulties in music but not Mandarin speech.

Congenital amusia is a musical disorder that mainly affects pitch perception. Among Mandarin speakers, some amusics also have difficulties in processing lexical tones (tone agnosics). To examine to what extent these perceptual deficits may be related to pitch production impairments in music and Mandarin speech, eight amusics, eight tone agnosics, and 12 age- and IQ-matched normal native Mandarin speakers were asked to imitate music note sequences and Mandarin words of comparable lengths. The results indicated that both the amusics and tone agnosics underperformed the controls on musical pitch production. However, tone agnosics performed no worse than the amusics, suggesting that lexical tone perception deficits may not aggravate musical pitch production difficulties. Moreover, these three groups were all able to imitate lexical tones with perfect intelligibility. Taken together, the current study shows that perceptual musical pitch and lexical tone deficits might coexist with musical pitch production difficulties. But at the same time these perceptual pitch deficits might not affect lexical tone production or the intelligibility of the speech words that were produced. The perception-production relationship for pitch among individuals with perceptual pitch deficits may be, therefore, domain-dependent.

[Effects of different irrigation minima on green period and cold-resistance physiological indices of Festuca arundinacea].

A pot experiment was conducted to study the effects of different irrigation minima [80% field capacity (FC), 70% FC, 60% FC and 50% FC] from late autumn to early winter on the green period and cold-resistance of Festuca arundinacea. Under the low temperature in winter, treatments 80% FC and 70% FC made the leaf relative water content, POD, CAT, and SOD activities, and chlorophyll, soluble sugar, and free proline contents of F. arundinacea maintained at a higher level, but made the MDA content and electrolyte leakage decreased, resulting in an increased cold-resistance of F. arundinacea. Treatment 80% FC made the green period of F. arundinacea prolonged by 4, 22 and 28 days, as compared with treatments 70% FC, 60% FC, and 50% FC, respectively, and made F. arundinacea have the shortest time to wither in winter and to turn green in spring, with the longest green period. Taking water-saving and water use efficiency into consideration, 70% FC would be the optimum irrigation low limit from late autumn to early winter for F. arundinacea.

[The value of determination of serum myoglobin in estimation of degree of illness and prognosis of patients with sepsis in Xining area].

OBJECTIVE: To investigate the value of determination of serum myoglobin (MYO) in estimation of the degree of illness and prognosis of patients with sepsis in Xining area. METHODS: Serum MYO was measured and acute physiological and chronic health estimationII (APACHEII) score was evaluated in 30 cases with sepsis within 24 hours of admission to emergency intensive care unit (EICU), and their correlation was analyzed. The patients were divided into two groups, survival group and death group according to the result within 28 days. The MYO and APACHEII score were analyzed in both groups. All cases were divided into three groups: namely <500 (n=10), 500-1 000 (n=14), >1 000 µg/L (n=6) groups, according to serum MYO value, and APACHEII score and dead case were compared among three groups. RESULTS: Sixteen patients survived, and 14 patients died. The level of serum MYO and APACHEII score were significantly lower in survival group than death group [MYO (µg/L): 607.85±499.40 vs. 976.21±370.10, APACHEII score: 15.50±4.43 vs. 18.93±3.63, t(1)=2.28, t(2)=2.29, both P<0.05]. With the elevation of serum MYO, the dead case was increased in sepsis patients (the dead case in MYO<500, 500-1 000, >1 000 µg/L groups was 2, 7, 5 cases, respectively,χ(2)=5.94, P<0.05), but there was no difference in APACHEII score among three groups. There was significant positive correlation between serum MYO and APACHEII score (r=0.407, P<0.05). CONCLUSION: Determination of serum MYO can reflect degree of illness and prognosis of sepsis patients in Xining area.

Self-consistent field lattice model study on the phase behavior of physically associating polymer solutions.

The phase behavior of physically associating polymer solutions, where the polymer chain contains a small fraction of "stickers" regularly placed along the backbone, is studied using self-consistent field lattice model. Two inhomogenous morphologies are observed. One is a microfluctuation homogenous (MFH) morphology, where the mean-field values of the local average concentrations of polymers phi(P)(r) and stickers phi(st)(r) slightly fluctuate around their respective bulk average values phi(P) and phi(st) and regularly from site to site. The other is a randomly close-packed micelle (RCPM) morphology. The structure of the micelle in RCPM morphology is similar to that of the "flower micelle" in the telechelic associative polymer system, where stickers are located in the core of the micelle and nonsticky groups in the corona. When phi(P) approximately or > 0.08, if homogenous associating polymer solutions are cooled, MFH morphology appears, and the system entirely changes from homogenous solutions (HS) to MFH morphology; If the solutions are cooled further, RCPM morphology appears. When phi(P) < 0.08, however, RCPM morphology appears immediately. If phi(P) < 0.53, a macroscopic phase separation, where the polymer rich phase is RCPM morphology, occurs. If phi(P) approximately or > 0.53, only RCPM morphology is found in the system. A peak appears in the temperature-dependent specific-heat curve C(V)(chi) at each transition point. For the HS-MFH transition, C(V)(chi) has an abrupt increase and a slow decrease, whereas for the MFH-RCPM transition, both the increase and the decrease in C(V)(chi) are slow. Furthermore, the system with only MFH morphology may be trapped in one of the two energy basins in a experimental time scale. However, the appearance of RCPM morphology means that the system is trapped in one of a series of "deeper" energy basins, and it is very difficult to jump off this deep basin into the one of MFH morphology or one of the other RCPM morphologies through thermal fluctuations.

[Effects of di-butyl phthalate on the reproductive system of adolescent male rats].

OBJECTIVE: To explore the effects of di-butyl phthalate (DBP) on the reproductive system of adolescent male rats. METHODS: Sprague-Dawley (SD) rats aged 5 weeks were assigned to receive corn oil (vehicle control) or DBP orally at 10, 100 and 500 mg/(kg x d) for 30 days. After the exposure, the testis, epididymis, liver and pituitary of the rats were weighted and their ratios to the body weight obtained. Histopathological changes of the testis and epididymis were examined by Hematoxylin-eosin staining, the levels of testosterone (T), luteinizing hormone (LH) and follicle stimulating hormone (FSH) in the serum were measured by radioimmunoassay, and the relative mRNA expressions of the steroidogenesis acute regulatory protein (StAR), proliferating cell nuclear antigen (PCNA), cytochrome P450 cholesterol side chain cleavage enzyme (P450scc) and scavenger receptor (SR) were detected by real-time quantitative RT-PCR. RESULTS: DBP induced significant histopathological changes in the testicular tissue at 100 and 500 mg/(kg x d), and decreased the testicular and epididymal weights, inhibited the mRNA expressions of StAR and PCNA, reduced the levels of T and LH, and elevated the level of FSH at 500 mg/(kg x d). At the dose of 10 mg/(kg x d), DBP increased serum LH and FSH and the mRNA expression of P450scc. While the SR mRNA expression showed no significant changes in all the groups. CONCLUSION: High level of DBP has apparent toxic effect on reproductive system of male rats. Low - dose DBP can increase the level of serum gonadotropin LH and affect the mRNA expression of P450scc in the testis.

Self-assembly of rod-coil-rod ABA-type triblock copolymers.

Self-assembled behavior of symmetric ABA rod-coil-rod triblock copolymer melts is studied by applying self-consistent-field lattice techniques in three-dimensional space. The phase diagram is constructed to understand the effects of the chain architecture on the self-assembled behavior. Four stable structures are observed for the ABA rod-coil-rod triblock, i.e., spherelike, lamellar, gyroidlike, and cylindrical structures. Different from AB rod-coil diblock and BAB coil-rod-coil triblock copolymers, the lamellar structure observed in ABA rod-coil-rod triblock copolymer melts is not stable for high volume fraction of the rod component (f(rod)=0.8), which is attributed to the intramolecular interactions between the two rod blocks of the polymer chain. When 0.3

Study of self-assembly of symmetric coil-rod-coil ABA-type triblock copolymers by self-consistent field lattice method.

The self-assembly of symmetric coil-rod-coil ABA-type triblock copolymer melts is studied by applying self-consistent field lattice techniques in a three-dimensional space. The self-assembled ordered structures differ significantly with the variation of the volume fraction of the rod component, which include lamellar, wave lamellar, gyroid, perforated lamellar, cylindrical, and spherical-like phases. To understand the physical essence of these phases and the regimes of occurrence, we construct the phase diagram, which matches qualitatively with the existing experimental results. Compared with the coil-rod AB diblock copolymer, our results revealed that the interfacial grafting density of the separating rod and coil segments shows important influence on the self-assembly behaviors of symmetric coil-rod-coil ABA triblock copolymer melts. We found that the order-disorder transition point changes from f(rod)=0.5 for AB diblock copolymers to f(rod)=0.6 for ABA triblock copolymers. Our results also show that the spherical-like and cylindrical phases occupy most of the region in the phase diagram, and the lamellar phase is found stable only at the high volume fraction of the rod.

A novel self-consistent-field lattice model for block copolymers.

We develop a self-consistent-field lattice model for block copolymers and propose a novel and general method to solve the self-consistent-field equations. The approach involves describing the polymer chains in a lattice and employing a two-stage relaxation procedure to evolve a system as rapidly as possible to a free-energy minimum. In order to test the validity of this approach, we use the method to study the microphases of rod-coil diblock copolymers. In addition to the lamellar and cylindrical morphologies, micellar, perforated lamellar, gyroid, and zigzag structures have been identified without any prior assumption of the microphase symmetry. Furthermore, this approach can also give the possible orientation of the rods in different structures.