Potential toxicity of graphene (oxide) quantum dots via directly covering the active site of anterior gradient homolog 2 protein.

Graphene quantum dots (GQDs) have attracted significant attention in biomedicine, while extensive investigations have revealed a reverse regarding the potential biotoxicity of GQDs. In order to supplementing the understanding of the toxicity profile of GQDs, this study employs a molecular dynamics (MD) simulation approach to systematically investigate the potential toxicity of both GQDs and Graphene Oxide Quantum Dots (GOQDs) on the Anterior Gradient Homolog 2 (AGR2) protein, a key protein capable of protecting the intestine. We construct two typical simulation systems, in which an AGR2 protein is encircled by either GQDs or GOQDs. The MD results demonstrate that both GQDs and GOQDs can directly make contact with and even cover the active site (specifically, the Cys81 amino acid) of the AGR2 protein. This suggests that GQDs and GOQDs have the capability to inhibit or interfere with the normal biological interaction of the AGR2 active site with its target protein. Thus, GQDs and GOQDs exhibit potential detrimental effects on the AGR2 protein. Detailed analyses reveal that GQDs adhere to the Cys81 residue due to van der Waals (vdW) interaction forces, whereas GOQDs attach to the Cys81 residue through a combination of vdW (primary) and Coulomb (secondary) interactions. Furthermore, GQDs aggregation typically adsorb onto the AGR2 active site, while GOQDs adsorb to the active site of AGR2 one by one. Consequently, these findings shed new light on the potential adverse impact of GQDs and GOQDs on the AGR2 protein via directly covering the active site of AGR2, providing valuable molecular insights for the toxicity profile of GQD nanomaterials.

A Magnetic Field Sensor Based on Directional Coupling in a Magnetic Fluid-Filled Photonic Crystal Fiber.

In this paper, a dual-core photonic crystal fiber (DC-PCF) sensitivity sensor filled with magnetic liquid is introduced and investigated with the finite element method (FEM). To regulate the energy coupling involving the two cores, the magnetic fluid is filled into the pore between the two cores. To adjust the coupling between the supermodes in the DC-PCF, the refractive index (RI) of the air hole filled magnetic fluid may change due to the external magnetic field. This specifically created a magnetic fluid-filled DC-PCF; the magnetic fluid-filled hole is not used as the core for energy transmission, thus avoiding transmission loss. The dip wavelength and the magnetic field displayed an excellent linear connection between 80 and 260 Oe, depending on the numerical data. The detection sensitivity of the magnetic field reached 515.75 pm/Oe at a short fiber length of 482 µm. The designed magnetic fluid-filled DC-PCF has high sensitivity and small volume and has great application prospects in magnetic field detection in the medical and industrial fields.

Acid/GSH Dual-Responsive Endosome Escape Dual Pro-drug Micelles Targeted Synergistic Treatment for A549/ADR.

The resistance of cancer cells to anticancer drugs has been recognized as one of the main reasons for chemotherapy failure. Multidrug combination therapy is one of the most effective ways to solve this problem. Therefore, in this article, we designed and synthesized a pH/GSH dual-responsive camptothecin/doxorubicin (CPT/DOX) dual pro-drug synergistic treatment system with the aim of overcoming the resistance of non-small cell lung cancer A549/ADR cells to DOX. The pro-drug cRGD-PEOz-S-S-CPT (cPzT) was obtained by linking CPT to poly(2-ethyl-2-oxazoline) (PEOz) with endosomal escape properties through a GSH-responsive disulfide bond and modifying it with the targeted peptide cRGD. The pro-drug mPEG-NH-N=C-DOX (mPX) was synthesized by attaching DOX to polyethylene glycol (PEG) through acid-sensitive hydrazone bonds. The dual pro-drug micelles cPzT/mPX configured according to the CPT/DOX mass ratio of 3:1 showed a strong synergistic therapeutic effect at IC50 with a combined therapy index CI = 0.49, far less than 1. Moreover, with the further improvement of the inhibition rate, the 3:1 ratio showed a stronger synergistic therapeutic effect than other ratios. The cPzT/mPX micelles not only had better targeted uptake ability but also showed a better therapeutic effect in both 2D and 3D tumor suppression assays relative to free CPT/DOX and significantly enhanced the penetration ability into solid tumors. In addition, the results of confocal laser scanning microscopy (CLSM) showed that cPzT/mPX could effectively overcome the resistance of A549/ADR cells to DOX by delivering DOX into the nucleus to exert its effect. Thus, this dual pro-drug synergistic therapy system combining targeting and endosomal escape ability provides a possible strategy to overcome tumor drug resistance.

Study on complications of osteoporosis based on network pharmacology.

Osteoporosis is a serious threat to human life. Guben Zenggu Granule is an empirical prescription for clinical treatment of osteoporosis. MC3T3-E1 cells are mouse osteogenic precursor cells with osteogenic differentiation, and are classic cells for studying bone metabolism and osteogenic mechanism, as well as mechanical stimulation sensitive cells. Therefore, it can be inferred that Guben Zenggu granule can repair MC3T3-E1 cells under continuous static pressure overload. This study aims to through the network of pharmacology and gene sequencing method, reveal thrift increase bone particles under the condition of continuous static pressure overload on osteogenesis mechanism of MC3T3-E1 cells. In the process of analysis, from a variety of 98 compounds was predicted in the database, a collection of 474 goals, a total of 29,164 difference between two groups of genes. Then, construction of composite targets between cells and predict targets and protein - protein interaction networks, and through the cluster analysis to further explore the relationship between the target. In addition, linkages between target proteins and cells were further identified using Gene Ontology (GO) and Pathways (KEGG Pathway). Finally, the repair effect of Guben Zenggu granule on MC3T3-E1 cells under continuous static pressure overload was verified through experiments, so as to accurately explain the pharmacodynamic mechanism of Traditional Chinese medicine.

Strategy evaluation and optimization with an artificial society toward a Pareto optimum.

Strategy evaluation and optimization in response to troubling urban issues has become a challenging issue due to increasing social uncertainty, unreliable predictions, and poor decision-making. To address this problem, we propose a universal computational experiment framework with a fine-grained artificial society that is integrated with data-based models. The purpose of the framework is to evaluate the consequences of various combinations of strategies geared towards reaching a Pareto optimum with regards to efficacy versus costs. As an example, by modeling coronavirus 2019 mitigation, we show that Pareto frontier nations could achieve better economic growth and more effective epidemic control through the analysis of real-world data. Our work suggests that a nation's intervention strategy could be optimized based on the measures adopted by Pareto frontier nations through large-scale computational experiments. Our solution has been validated for epidemic control, and it can be generalized to other urban issues as well.

Stable structures and superconducting properties of Ca-La-H compounds under pressure.

The calcium hydrides and lanthanum hydrides under high pressures have been reported to have good superconducting properties with high-TC. In this work, the structures and superconductivities of Ca-La-H ternary hydrides have been studied by genetic algorithm and density functional theory calculations. Our results show that at the pressure range of 100-300 GPa, the most stable structure of CaLaH12has aCmmmsymmetry, in which there is a H24hydrogen cage. It can be expected to have high possibility to be synthesized due to its large stability. Furthermore, the predictedTCof theCmmm-CaLaH12structure is about 140 K at 150 GPa, and when the pressure decreases to 30 GPa, the CaLaH12structure with aC2/msymmetry has a predictedTCof about 49 K. The CaLaH12is suggested to be a stable good superconductor with large stability and performs well at relatively low pressures.

Precise delivery of multi-stimulus-responsive nanocarriers based on interchangeable visual guidance.

Cancer treatment is imminent, and controlled drug carriers are an important development direction for future clinical chemotherapy. Visual guidance is a feasible means to achieve precise treatment, reduce toxicity and increase drug efficacy. However, the existing visual control methods are limited by imaging time-consuming, sensitivity and side effects. In addition, the ability of the carrier to respond to environmental stimuli in vivo is another difficulty that limits its application. Here, we propose a highly stimulus-responsive GC liposome with precise tracing and sensitive feedback capabilities. It combines magnetic resonance imaging and fluorescence imaging, and addresses the need for precise visualization by alternating imaging modalities. More importantly, GC liposomes are a carrier that can accumulate stimuli. In this paper, by tracking the fragmentation process of empty GC and drug-loaded D-GC liposomes, we confirm the synergistic effect between multiple stimuli, which can result in a more efficient drug release performance. Finally, in mice models we examined the GC liposome imaging approach and the D-GC + UV group guided by this visualization exhibited the highest tumor inhibition efficiency (6.85-fold). This study highlights the advantages of alternate visualization-guided and co-stimulation treatment strategies, and provides design ideas and potential materials for efficient and less toxic cancer treatments.

Series of High Magnetic Resonance-Guided Photoinduced Nanodelivery Systems for Precisely Improving the Efficiency of Cancer Therapy.

Nanochemotherapy is recognized as one of the most promising cancer treatment options, and the design of the carrier has a crucial impact on the final efficacy. To precisely improve the efficacy and reduce the toxicity, we combined the clinical contrast agent (Gd-DTPA) with a stimulus-sensitive o-nitrobenzyl ester and then prepared a series of nNBGD lipids by varying the carbon chain length of the hydrophobic group. The self-assembled nNBGD liposomes can be tracked by MRI to localize the aggregation of drug carriers in vivo, so as to prompt the application of light stimulation at the optimal time to facilitate the precise release of carriers at the lesion site. And the application potential of this strategy was verified with 88% tumor suppression effect in the 12NBGD-DOX+UV group. In addition, this paper emphasizes that small differences in structure can affect the overall performance of the carriers. By exploration of the differences in stability, drug loading, stimulus responsiveness, MRI imaging effect, and toxicity of the series of nNBGD carriers, the relationship between the length of the hydrophobic group of nNBGD lipids and the overall performance of the carriers is given, which provides experimental support and design reference for other carriers.

Study on superconducting Li-Se-H hydrides.

The structures, stabilities and superconducting properties of LiSeHn (n = 4-10) hydrides at 150-300 GPa were studied by the genetic algorithm (GA) and DFT calculation method. Three stable stoichiometries of LiSeH4, LiSeH6 and LiSeH10 were uncovered under high pressure. Four other metastable stoichiometries of LiSeH5, LiSeH7, LiSeH8, and LiSeH9 were also studied. By analyzing the electronic band structure and electronic density of states, C2 LiSeH4, Pmm2 LiSeH6 and C2 LiSeH10 were all found to be metal phases above 150 GPa. Electron-phonon coupling calculations showed that C2 LiSeH4 and Pmm2 LiSeH6 were promising superconductors. The predicted Tc values of C2 LiSeH4 and Pmm2 LiSeH6 were 77 K at 200 GPa and 111 K at 250 GPa, respectively.

Sensitive and precise visually guided drug delivery nanoplatform with dual activation of pH and light.

Controlled-release drug carriers in cancer therapy are the most ideal way to reduce toxicity and improve drug efficacy. Since light stimulation is precise and operable, most multi-stimulation response carriers utilize phototherapy to enhance release efficiency. However, phototoxicity severely limits the application of phototherapy. Herein, we designed and synthesized a Cou-ONB lipid with sensitive fluorescence feedback and multi-stimulus response. COBL liposomes prepared from Cou-ONB lipids will passively aggregate at the tumor and guide phototherapy by fluorescence. More importantly, it can reflect the drug release effect in vivo through its own sensitive fluorescence changes, further enabling precise phototherapy and reducing phototoxicity. In this paper, the multi-stimulus superimposed response and precise fluorescence-guided performance of COBL liposomes were investigated at the molecular, liposome, cellular, and animal levels. Finally, tumor treatment experiments showed that the d-COBL-UV group had the best tumor suppression effect (5.3-fold). This paper highlights a real-time fluorescence-guided multi-stimulus superposition strategy and provides a design idea to precisely implement exogenous stimuli by displaying the degree of drug release, aiming to achieve less toxic and more efficient cancer therapy through timely and precise multi-stimulation. STATEMENT OF SIGNIFICANCE: Multi-stimulus responsive drug carriers have been extensively developed in the last decade. Visual guidance is an important tool to achieve precision medicine and precise control of drug release. However, the available visualization materials are more aimed at directing stimulation at the optimal moment. There is little discussion on when to stop exogenous stimulation and how to minimize the damage of stimulation to the patient. Here, we provide a Cou-ONB lipid that not only responds to multiple stimuli, but also provides sensitive feedback on its own dissociation with a fluorescent signal so that physicians can adjust exogenous stimuli in a timely manner. This paper provides insights to facilitate precision drug delivery systems, providing viable design ideas for precise, efficient, and less toxic cancer therapies.

Evaluating the mitigation strategies of COVID-19 by the application of the CO2 emission data through high-resolution agent-based computational experiments.

The negative consequences, such as healthy and environmental issues, brought by rapid urbanization and interactive human activities result in increasing social uncertainties, unreliable predictions, and poor management decisions. For instance, the Coronavirus Disease (COVID-19) occurred in 2019 has been plaguing many countries. Aiming at controlling the spread of COVID-19, countries around the world have adopted various mitigation and suppression strategies. However, how to comprehensively eva luate different mitigation strategies remains unexplored. To this end, based on the Artificial societies, Computational experiments, Parallel execution (ACP) approach, we proposed a system model, which clarifies the process to collect the necessary data and conduct large-scale computational experiments to evaluate the effectiveness of different mitigation strategies. Specifically, we established an artificial society of Wuhan city through geo-environment modeling, population modeling, contact behavior modeling, disease spread modeling and mitigation strategy modeling. Moreover, we established an evaluation model in terms of the control effects and economic costs of the mitigation strategy. With respect to the control effects, it is directly reflected by indicators such as the cumulative number of diseases and deaths, while the relationship between mitigation strategies and economic costs is built based on the CO2 emission. Finally, large-scale simulation experiments are conducted to evaluate the mitigation strategies of six countries. The results reveal that the more strict mitigation strategies achieve better control effects and less economic costs.

Magnetic Resonance Imaging-Guided Multi-Stimulus-Responsive Drug Delivery Strategy for Personalized and Precise Cancer Treatment.

The emergence of nano-targeted controlled release liposomal drug carriers has provided a breakthrough in cancer therapy. However, their clinical efficacy is unsatisfactory, which is related to individualized differences in targeted drugs and poor in vivo release efficiency. In this paper, we prepared a class of personalized targeted and precisely controlled-release therapeutic drug carriers (GF liposomes) by co-assembling targeting and traceable o-nitrobenzyl ester lipids to propose a magnetic resonance imaging (MRI)-guided personalized in vivo targeted drug screening strategy and a multi-stimulus superimposed controlled-release strategy. Furthermore, by following the drug release process of drug-loaded liposomes (GF-D), it was found that these liposomes could rely on energy superposition to achieve more sensitive and efficient controlled drug release. In addition, the indispensable adjustment of liposome formulation for personalized MRI-based targeted therapy was verified by differential cellular uptake and in vivo magnetic resonance imaging. In the end, the 10.22-fold tumor suppression effect in the stimulus superposition group (GF-D-UV) indicates that the multi-stimulus cumulative response strategy and MRI-guided in vivo screening strategy can more effectively treat cancer. This contribution provides a concise and clever design idea for the future development of personalized precise and efficient clinical cancer therapies.

An MRI-guided targeting dual-responsive drug delivery system for liver cancer therapy.

The targeting dual-responsive drug delivery system was employed for cancer treatment as a positive strategy. Herein, Lactobionic acid (LA)-modified and non-modified UV/reduction dual-responsive molecules (10,10-NB-S-S-P-LA and 10,10-NB-S-S-P-OMe) were synthesized. Functional magnetic resonance imaging (MRI) contrast agent (12,12-NB-DTPA-Gd) was mixed with 10,10-NB-S-S-P-LA or 10,10-NB-S-S-P-OMe in the optimal ratio (3:1) to develop targeted empty liposomes (GNSPL) or non-targeted empty liposomes (GNSPM) with superior UV/reduction dual-responsiveness, biocompatibility and magnetic resonance imaging (MRI) performance. The drug-loaded liposomes (GNSPLD and GNSPMD) can keep stable in two weeks, and the drug cumulative release rate reached to the maximum under dual stimulation of ultraviolet (UV) and reducing agent (TCEP). The treatment with GNSPLD + UV significantly inhibited the growth and migration of cancer cells in vitro. The GNSPLD liposomes were more effectively accumulated in tumor site than GNSPMD liposomes, due to the targeting property of GNSPLD liposomes. The treatment with GNSPLD + UV showed a better therapeutic efficacy than Doxorubicin (DOX) in vivo, and almost no side effects during the treatment period. Thus, the MRI-guided targeting dual-responsive drug delivery system provided a reliable therapeutic strategy for treating liver cancer.

Endogenous reactive oxygen species burst induced and spatiotemporally controlled multiple drug release by traceable nanoparticles for enhancing antitumor efficacy.

Reactive oxygen species (ROS) are not only used as a therapeutic reagent in chemodynamic therapy (CDT), to stimulate the release of antineoplastic drugs, they can also be used to achieve a combined effect of CDT and chemotherapy to enhance anticancer effects. Herein, we synthesized a pH-responsive prodrug (PEG2k-NH-N-DOX), ROS-responsive prodrug (PEG2k-S-S-CPT-ROS), organic CDT agents (TPP-PEG2k-LND, TPP-PEG2k-TOS), and T1-enhanced magnetic resonance imaging contrast agents (Gd-DTPA-N16-16), and used them to encapsulate combrestatinA4 (CA4) to prepare traceable pH/ROS dual-responsive multifunctional nanoparticles (TLDCAG NPs) with endogenous ROS burst and spatiotemporally controlled multiple drug release ability. Firstly, TLDCAG NPs were accumulated in the tumor cell microenvironment via an enhanced permeability and retention (EPR) effect. Secondly, CA4 was released and specifically destroyed angiogenesis to facilitate the interaction between the tumor and the remaining TLDCG NPs. After accumulating in tumor cells, the TLDCG NPs could be destroyed under acidic conditions to quickly release doxorubicin (DOX), TPP-PEG2k-LND, and TPP-PEG2k-TOS. Thirdly, TPP-PEG2k-LND and TPP-PEG2k-TOS quickly targeted mitochondria, induced endogenous ROS bursts, reduced the mitochondrial membrane potential, and induced tumor cell apoptosis. Endogenous ROS can not only be used as a therapeutic reagent for CDT, but also can cut off the thioketal bond in PEG2k-S-S-CPT-ROS and release camptothecin (CPT). Finally, TLDCAG NPs were traced by magnetic resonance imaging (MRI). Furthermore, in vitro and vivo results indicate that the TLDCAG NPs have vigorous antitumor activity and negligible systemic toxicity. Therefore, the TLDCAG NPs provide an efficient strategy for enhancing antitumor efficacy.

A traceable, GSH/pH dual-responsive nanoparticles with spatiotemporally controlled multiple drugs release ability to enhance antitumor efficacy.

Constructing highly efficient and multifunctional nanoparticles to overcome the multiple challenges of targeted drug delivery is a new strategy urgently needed in tumor therapy. Here, we synthesized pH-responsive prodrug (PEG2K-NH-N-DOX), GSH-responsive prodrug (PEG2K-S-S-CPT), folate-receptor targeting polymers (FA-PEG2K-L8, FA-PEG2K-TOS) and T1-enhanced magnetic resonance imaging contrast agents (Gd-DTPA-N16-16), used to encapsulate combrestatinA4 (CA4) to prepare multifunctional nanoparticles (FTDCAG NPs). Unlike other nanoparticles, FTDCAG NPs contains three drugs with the ability to control the release in time and space, which can maximize the effectiveness of precise cancer chemotherapy. We first confirmed that specific binding between FTDCAG NPs and overexpressed folate-receptor cells by flow cytometry and confocal laser scanning microscopy. We then investigated the spatiotemporally controlled release ability of FTDCAG NPs loaded with doxorubicin (DOX), CA4 and camptothecin (CPT). Relative to pH = 7.4, the release efficiency of CA4 in the pH = 6.5 increased by 63.4 %. The first released CA4 is able to destroy the angiogenesis and help tumor cells to be exposed to the remaining FTDCG NPs. After being internalized into the tumor cells, FTDCG NPs is disassembled and the CPT and DOX were released due to the increase of intracellular GSH concentration and the decrease of pH value. Besides, the relaxation time of FTDCAG NPs is 3.86 times that of clinical Gd-DTPA, and the in vitro and vivo T1-weighted imaging is brighter, which can be used to trace the nanoparticles by MRI. Therefore, FTDCAG NPs provide an efficient strategy for the design of multifunctional drug delivery systems for enhancing antitumor efficacy.

[Improved Research of Adjustable External Fixation Device for Lower Limbs Based on Semiconductor Refrigeration Sheet].

A kind of adjustable external fixation device for lower extremity is designed. The circuit is mainly composed of TEC1-00703 semiconductor refrigeration chip, HZC-30A pressure sensor, STC89C52RC single chip microcomputer and other electrical components. It can realize the timing intelligent temperature control and meet the local fixed-point refrigeration. The design of adjustable structure and the application of intelligent air cushion can satisfy the full fixation of lower limbs of different individuals. Its operation does not need much medical knowledge. It can solve the problem of emergency transportation and follow-up treatment of lower limb injury in ice and snow sports. It has a good application prospect and universality.

Effective wound dressing based on Poly (vinyl alcohol)/Dextran-aldehyde composite hydrogel.

Wound dressing is of significant importance to promote cutaneous wound healing process. To develop an effective wound dressing, a PVA/DA hydrogel was prepared using a Poly (vinyl alcohol)/Dextran-aldehyde solution blend, followed by crosslinking via freeze-thaw method and freeze-drying. We characterized the hydrogel by infrared spectroscopy, mechanical property tests, swelling behavior test and biocompatibility test. Results showed that the PVA/DA hydrogels had a 3-dimensional, highly porous structure with uniformly distributed pores of 5-10 µm, strong tensile strength of 5.6 MPa, efficient ability to absorb fluid of 6 time its weight and suitable water vapor transmission rate of 2100 g m-2day-1 to keep a moist environment and good biocompatibility shown by very low hemolysis and no cytotoxicity. In wound healing tests using a full-thickness skin wound model, macroscopic observations showed that the wound covered by the PVA/DA hydrogel almost reached complete healing faster by 10 days, while histological analysis indicated a faster regeneration of skin. Thus, the PVA/DA hydrogel was suitable for application as a wound dressing and may have potential for use in various biomedical applications.

A highly efficient, in situ wet-adhesive dextran derivative sponge for rapid hemostasis.

Uncontrolled hemorrhage is closely related to the high risk of death. However, local hemostats still have various defects and side effects. Herein, an aldehyde dextran (PDA) sponge with proper absorption and adhesion properties is developed for hemorrhage control. PDA sponge with pore size of ∼30-50 µm fabricated by lyophilization not only absorbs blood quickly (47.7 g/g), but also possesses strong tissue adhesion (∼100 kPa). PDA sponge with low cytotoxicity and hemolysis achieves effective hemostasis and remarkable blood loss reduction in the ear vein, femoral artery and liver injuries of rabbit models. Furthermore, the exploration of hemostatic mechanisms related to tissue, blood, plasma, cells and coagulation system indicates that PDA sponge can significantly accelerate coagulation by rapid wound block, fast cells aggregation and initiation, and high coagulation factors concentration, instead of by the coagulation cascade activation. Importantly, this hemostat exhibits excellent biodegradability and nearly no skin irritation. Overall, the biodegradable and tissue adhesive PDA sponge will be a promising quick-hemostatic dressing for uncontrollable hemorrhage.

Synthesis and evaluation of mono- and multi-hydroxyl low toxicity pH-sensitive cationic lipids for drug delivery.

Cationic lipids can easily assemble into spherical liposomes in aqueous phase which showed unique superiority in drug and gene delivery. However, the toxicity of cationic lipids is still an obstacle to application. To develop low toxicity cationic lipids, we designed two cationic lipids contained different number of hydroxyl groups. Biocompatible mono-hydroxyl and multi-hydroxyl galactose head group was respectively modified to a biodegradable quaternary amine lipid, and two novel hydroxyl cationic lipids were synthesized and characterized by MS, 1H NMR and 13C NMR. Two lipids showed good surface activity and both of them can assemble to about 80 nm stable small unilamellar vesicles (SUVs) with cholesterol in aqueous phase. Both of lipids showed relatively lower toxicity than the well-known cationic lipid 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP). In vitro 24 h IC50 of two assemblies were more than 50 µg/mL, which were about 10 µg/mL higher than the IC50 of DOTAP. Multi-hydroxyl galactose lipids group showed much lower toxicity than mono-hydroxyl lipids group. Moreover, Both of the assemblies with lower hemolysis were nearly non-hemolytic risk under the concentration of 30 µg/mL. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) showed that the average sizes of both doxorubicin (DOX) loaded liposomes were about 110 nm. The DOX entrapment efficiencies of galactose liposome and mono-hydroxyl liposome were 58% and 91%, respectively. Both of the DOX loaded liposomes were stable after one month placed at room temperature. Two DOX loaded liposomes showed better anti-cancer effect than free DOX above 5 µg/mL, and they can be internalized into cells and produce more release of DOX inside MCF-7 cells and HepG2 cells at pH 5.0. These results suggested that synthesized lipids are suitable as potential low toxicity cationic drug delivery systems.

Tissue partition and risk assessments of trace elements in Indo-Pacific Finless Porpoises (Neophocaena phocaenoides) from the Pearl River Estuary coast, China.

Throughout the last few decades, an increased number of stranded marine mammals, particularly the Indo-Pacific Finless Porpoises (Neophocaena phocaenoides), were observed in the Pearl River Estuary (PRE). As long-lived, apex predators vulnerable to bioaccumulation of contaminants, the tissue residue levels and health risk of trace elements (TEs) in N. phocaenoides from the PRE have been little studied. Eleven typical TEs distributed in skin, liver and kidney tissues were investigated from 25 specimens stranded along the PRE from 2007 to 2015 in the present study. It revealed that most TEs were highly accumulated in internal organs (liver and kidney), except for Zn with high residue levels in external skin. Compared with the TEs in prey items, the residue levels of Hg, Se, Zn, Cu, Cd and Cr in N. phocaenoides increased 4-618 times, indicating a potentially significant biomagnification. Sex-related differences of TE accumulation were not obvious, except for renal Mn, in which the females showed lower mean concentrations than males. Significantly positive correlations between body length and TE levels were found for Hg, Se and Cd. Results of the calculated risk quotients (RQ) suggested that the risks to N. phocaenoides from consumption of prey items were generally low, but further attentions should be paid to Cd, Cr, Cu, Hg and As due to the elevated RQ values. The concentrations of Hg, Cd and Se in the epidermis were positively correlated with the levels found in internal organs. Our investigation provides evidence to support the use of skin as one biomonitoring approach on Hg, Cd and Se contamination of internal tissues in this species.