Analysis of behavioral disability and construction of a disability scale for the elderly in Shanghai.

BACKGROUND: With the gradual aging of China's population development, the number of disabled elderly has increased significantly. OBJECTIVE: In order to better solve the problem of life care for these elderly people, it is necessary to conduct in-depth and detailed research on the specific conditions of disabled elderly people, in order to differentiate different conditions for care and set appropriate insurance provisions. METHODS: Based on the detailed analysis of the basic behavioral ability of the elderly, and referring to the International Disability standards, this paper refines the three basic living ability indicators of physiological behavior, cognitive behavior and interpersonal behavior, and integrates the cultural elements of assimilation, continuity, fusion and cohesion with Chinese characteristics. A more systematic and perfect five-level disability scale which conforms to the national conditions of China is designed. RESULTS: The disability of the elderly in Shanghai was investigated with the newly constructed scale, and a detailed analysis and five-level division were made. CONCLUSION: Experiments show that the results of this study can more effectively establish the disability level of the elderly in China.

Near infrared light triggered reactive oxygen species responsive nanoparticles for chemo-photodynamic combined therapy.

Currently, the strategy of combining photodynamic therapy (PDT) and chemotherapy for enhancing cancer therapeutic efficiency has aroused extensive interest. Nonetheless, weaknesses such as low local concentration, uncontrollable release of the drug, a non-suitable treatment light source, and a low response to the tumor site of PDT lead to the combined treatment effect not being ideal. Herein, we proposed simple and intelligent ROS-responsive zinc phthalocyanine sensitized TiO2 nanoparticles which conjugated with chlorambucil (CBL) (mTiO2-BCBL@ZnPC NPs) in an attempt to solve these issues. Not only were the nanoparticles triggered in near infrared radiation (NIR) for PDT with various reactive oxygen species (ROS) being generated, but the nanoparticles also realized the controllable release of CBL by H2O2, a major kind of ROS, through cleavage of the phenylboronic ester between CBL and the nanoparticle. Impressively, the controllable release of CBL under NIR irradiation showed an on-off characteristic and time dependency. In addition, the well-defined mTiO2-BCBL@ZnPC NPs with a 30 nm average diameter showed good stability and biocompatibility. The in vitro cytotoxicity studies demonstrated that the mTiO2-BCBL@ZnPC NPs were more cytotoxic under NIR irradiation than the mTiO2@ZnPC NPs and CBL, while the mTiO2-BCBL@ZnPC NPs were less cytotoxic under dark conditions. The above results implied that photo-controlled drug release is a promising choice for cancer therapy due to its high selectivity, good safety and low side-effects, and would be expected to be used in chemo-photodynamic combined therapy for improving the therapeutic efficiency.

Systemic toxicity induced by aggregated layered double hydroxide nanoparticles.

Layered double hydroxide (LDH) nanoparticles are emerging as one of the promising nanomaterials for biomedical applications, but their systemic toxicity in vivo has received little attention. In the present study, the effects of inorganic nanoparticle aggregation on their systemic toxicity were examined. Remarkably, aggregation was observed after the mixing of naked LDH nanoparticles with saline or erythrocytes. Significant accumulation of the naked LDH nanoparticles in the lungs of mice was detected 1 h after intravenous administration, and the survival rate of mice was 0% after 6 repeated injections. Furthermore, flocculent precipitates in the alveoli and congestion in the lung interstitium were observed in the dead mice. However, lipid membrane-coated LDH nanoparticles would not form aggregates and could be injected intravenously >6 times without causing death. These findings suggested that repeated injections of LDH were lethal even at low dose (30 mg/kg), and lipid membrane coating can be considered as an approach for reducing this risk.

Injectable, NIR/pH-Responsive Nanocomposite Hydrogel as Long-Acting Implant for Chemophotothermal Synergistic Cancer Therapy.

In this study, gold nanorods (GNRs) were incorporated into the hydrogel networks formed by the copolymerization of N-isopropylacrylamide (NIPAm) and methacrylated poly-ß-cyclodextrin (MPCD)-based macromer to fabricate an injectable and near-infrared (NIR)/pH-responsive poly(NIPAm-co-MPCD)/GNRs nanocomposite hydrogel, which could serve as a long-acting implant for chemophotothermal synergistic cancer therapy. The nanocomposite hydrogel showed superior mechanical and swelling properties, gelation characteristics, and excellent NIR-responsive property. A hydrophobic acid-labile adamantane-modified doxorubicin (AD-DOX) prodrug was loaded into the hydrogel efficiently by host-guest interaction. The nanocomposite hydrogel exhibited a manner of sustained drug release and could sustain the slow and steady release of DOX for more than 1 month. The pH-responsive release of DOX from the nanocomposite hydrogel was observed owing to the cleavage of acid-labile hydrazone bond between DOX and the adamantyl group in acidic environment. NIR irradiation could accelerate the release of DOX from the networks, which was controlled by the collapse of the hydrogel networks induced by photothermal effect of GNRs. The in vitro cytotoxicity test demonstrated the excellent biocompatibility and photothermal effect of the nanocomposite hydrogel. Moreover, the in situ-forming hydrogel showed promising tissue biocompatibility in the mouse model study. The in vivo antitumor test demonstrated the capacity of the nanocomposite hydrogel for chemophotothermal synergistic therapy with reduced adverse effects owing to the prolonged drug retention in the tumor region and efficient photothermal effect. Therefore, this injectable and NIR/pH-responsive nanocomposite hydrogel exhibited great potential as a long term drug delivery platform for chemophotothermal synergistic cancer therapy.

Calcium phosphate nanoparticles functionalized with alendronate-conjugated polyethylene glycol (PEG) for the treatment of bone metastasis.

Because of the peculiarity of the bone microstructure, the uptake of chemotherapeutics often happens at non-targeted sites, which induces side effects. In order to solve this problem, we designed a bone-targeting drug delivery system that can release drug exclusively in the nidus of the bone. Alendronate (ALN), which has a high ability to target to hydroxyapatite, was used to fabricate double ALN-conjugated poly (ethylene glycol) 2000 material (ALN-PEG2k-ALN). The ALN-PEG2k-ALN was characterized using 1H NMR and 31P NMR and FTIR. ALN-PEG2k-ALN-modified calcium phosphate nanoparticles (APA-CPNPs) with an ALN targeting moiety and hydrophilic poly (ethylene glycol) arms tiled on the surface was prepared for bone-targeted drug delivery. The distribution of ALN-PEG2k-ALN was tested by X-ray photoelectron spectroscopy. Isothermal titration calorimetry data indicated that similar to free ALN, both ALN-PEG2k-ALN and APA-CPNPs can bind to calcium ions. The bone-binding ability of APA-CPNPs was verified via ex vivo imaging of bone fragments. An in vitro release experiment demonstrated that APA-CPNPs can release drug faster in an acid environment than a neutral environment. Cell viability experiments indicated that blank APA-CPNPs possessed excellent biocompatibility with normal cells. Methotrexate (MTX) loaded APA-CPNPs have the same ability to inhibit cancer cells as free drug at high concentrations, while they are slightly weaker at low concentrations. All of these experiments verified the prospective application of APA-CPNPs as a bone-targeting drug delivery system.

Inclusion complexes of HP-ß-cyclodextrin with agomelatine: Preparation, characterization, mechanism study and in vivo evaluation.

Agomelatine (AGM), is efficacious in both the acute phase and the continuation phase of depression. However, its poor water-solubility, low bioavailability and polymorphism limit its pharmacological effects. To address these problems, agomelatine-hydroxypropyl-ß-cyclodextrin inclusion complex (AGM/HPß-CD) was prepared successfully by freeze-drying. The products was evaluated by structural characterization, solubilization test, in-situ absorption of rat intestinal tract and pharmacokinetic study. In addition, thermodynamic studies were performed, the results indicated that the inclusion process was enthalpy-determined and exothermic nature of complexation, signifying the role of steric interactions in complex formation. Molecular docking of AGM with HPß-CD has been conducted as well to verify the experimental findings and predict the stable molecular structure of the inclusion complex. The in vivo data showed that, AGM was mainly absorbed in duodenum and jejunum by passive diffusion. AGM/HPß-CD inclusion complex displayed earlier Tmax and higher Cmax, and the AUC0-12h was approximately twice larger than its physical mixture. These results suggested that AGM/HPß-CD inclusion complex was established with 1:1 stoichiometry through the naphthalene group of AGM and it was deeply inserted into the cavity of HPß-CD, and the inclusion complex could significantly enhance the oral bioavailability of AGM.

A novel capsular tension ring as local sustained-release carrier for preventing posterior capsule opacification.

One of the most important and challenging goals in pharmaceutical prevention for posterior capsule opacification is to preserve an effective drug concentration in capsular bag for a long period without affecting the patients' vision. Here, a novel kind of composite, which was prepared by 2-hydroxyethyl methacrylate (HEMA) and methyl methacrylate (MMA) via a two-step process, was applied for capsular tension ring (CTR) as an implant that could deliver docetaxel (DTX) over a long period of time. The drug release rate of the composite could be controlled by the ethyleneglycol dimethacrylate (EGDMA) content and the ratio of HEMA/MMA as well as the structure of porous PMMA framework. The CTR could continuously release DTX for up to 6 weeks in vitro and maintain DTX in effective concentration in the aqueous humor after 42 days. Docetaxel-load capsular tension ring (DTX-CTR) presented strong inhibition on the lens epithelial cells in-vivo without obvious damage to normal tissues. These results indicate that the drug sustained-release CTR can provide a promising application in posterior capsule opacification prevention.

Laser-triggered intraocular implant to induce photodynamic therapy for posterior capsule opacification prevention.

Posterior capsule opacification (PCO) is one of the main reasons for loss of vision again after cataract surgery. In this study, intraocular lenses were modified with indocyanine green (ICG) and sealed up with PLGA to form long-term intraocular implants (ICG-IOL). When triggered by laser, ICG-IOL would induce photodynamic therapy (PDT). In-vitro cell viability assay and scratch wound healing assay demonstrated that ICG-IOL could effectively inhibit HLEpiC proliferation and migration without causing damage to the cells far away from it. Laser attenuation test indicated that ICG-IOL could be applied in vivo. In-vivo pharmacodynamics and safety study showed that ICG-IOL could significantly prevent the occurrence of PCO and was safe for intraocular normal tissue. All these results suggested that ICG-IOL would be a very promising candidate for PCO prevention.

Novel Galactosylated Poly(ethylene glycol)-Cholesterol for Liposomes as a Drug Carrier for Hepatocyte-Targeting.

In this study, three types of galactosylated cholesterol (i.e., gal-PEG194-chol, gal-PEG1000-chol and gal-PEG2000-chol) were synthesized with one terminal of polyethylene glycol of various chain lengths conjugated to the galactoside moiety, and the other terminal conjugated to the cholesterol. The galactose-modified liposomes were prepared by thin film-hydration method and doxorubicin (DOX) was loaded to the liposomes by using a ammonium sulfate gradient procedure. The liposomal formulations with galactosylated cholesterol were characterized. Flow cytometry and laser confocal scanning microscopy analyses showed that the galactose-modified liposomes facilitated the intracellular uptake of liposomes into HepG2 via asialoglycoprotein receptor (ASGP-R) mediated endocytosis. Cytotoxicity assay showed that the cell proliferation inhibition effect of galactose-modified liposomes was higher than that of the unmodified liposomes. Additionally, the study on frozen section of liver showed that the galactose-modified liposomes enhanced the intracellular uptake of liposomes into hepatocytes. Taken together, these results suggested that liposomes containing such galactosylated cholesterol (i.e., gal-PEG-chol), had a great potential as drug delivery carriers for hepatocyte-selective targeting.

Lipid-coated ZnO nanoparticles as lymphatic-targeted drug carriers: study on cell-specific toxicity in vitro and lymphatic targeting in vivo.

Lymphatic metastasis plays an important role in tumour recurrence. The applications of nanoparticles in the treatment of lymphatic metastatic tumours have been limited by targeting inefficiency and nonselective toxicity. Hence, in this report, we have developed lipid-coated ZnO nanoparticles (LZnO NPs) in an attempt to solve these issues. Using the microreactor method, we have fabricated ultrasmall (∼30 nm) core-shell-structured nanoparticles loaded with 6-mercaptopurine (6-MP). In vivo results show that the lipid shell induces a remarkable improvement in lymphotropism and biocompatibility compared to ZnO nanoparticles. Furthermore, the ZnO core exhibits not only pH-responsive behaviour to guarantee effective drug delivery, but also a strong preferential ability to kill cancerous cells, as a consequence of the generation of higher inducible levels of reactive oxygen species in rapidly dividing cells. Furthermore, LZnO NPs enhance the cytotoxicity of 6-MP, resulting from the improved internalization of nanoparticles through endocytosis. These findings indicate that LZnO NPs are a promising candidate for use as lymphatic-targeted drug carriers.

Improvement of pharmacokinetic and antitumor activity of layered double hydroxide nanoparticles by coating with PEGylated phospholipid membrane.

Layered double hydroxide (LDH) has attracted considerable attention as a drug carrier. However, because of its poor in vivo behavior, polyethylene glycolylated (PEGylated) phospholipid must be used as a coformer to produce self-assembled core-shell nanoparticles. In the present study, we prepared a PEGylated phospholipid-coated LDH (PLDH) (PEG-PLDH) delivery system. The PEG-PLDH nanoparticles had an average size of 133.2 nm. Their core-shell structure was confirmed by transmission electron microscopy and X-ray photoelectron spectroscopy. In vitro liposome-cell-association and cytotoxicity experiments demonstrated its ability to be internalized by cells. In vivo studies showed that PEGylated phospholipid membranes greatly reduced the blood clearance rate of LDH nanoparticles. PEG-PLDH nanoparticles demonstrated a good control of tumor growth and increased the survival rate of mice. These results suggest that PEG-PLDH nanoparticles can be a useful drug delivery system for cancer therapy.

Synthesis of novel tetravalent galactosylated DTPA-DSPE and study on hepatocyte-targeting efficiency in vitro and in vivo.

For the purposes of obtaining a hepatocyte-selective drug delivery system, a novel tetravalent galactosylated diethylenetriaminepentaacetic acid-distearoyl phosphatidylethanolamine (4Gal-DTPA-DSPE) was synthesized. The chemical structure of 4Gal-DTPA-DSPE was confirmed by proton nuclear magnetic resonance and mass spectrometry. The four galactose-modified liposomes (4Gal-liposomes) were prepared by thin-film hydration method, then doxorubicin (DOX) was encapsulated into liposomes using an ammonium sulfate gradient loading method. The liposomal formulations with 4Gal-DTPA-DSPE were characterized by laser confocal scanning microscopy and flow cytometry analysis, and the results demonstrated that the 4Gal-liposomes facilitated the intracellular uptake of DOX into HepG2 cells via asialoglycoprotein receptor-mediated endocytosis. Cytotoxicity assay showed that the cell proliferation inhibition effect of 4Gal-liposomes was higher than that of the conventional liposomes without the galactose. Additionally, pharmacokinetic experiments in rats revealed that the 4Gal-liposomes displayed slower clearance from the systemic circulation compared with conventional liposomes. The organ distributions in mice and the study on frozen sections of liver implied that the 4Gal-liposomes enhanced the intracellular uptake of DOX into hepatocytes and prolonged the circulation. Taken together, these results indicate that liposomes containing 4Gal-DTPA-DSPE have great potential as drug delivery carriers for hepatocyte-selective targeting.

Repeated injection of PEGylated solid lipid nanoparticles induces accelerated blood clearance in mice and beagles.

Surface modification of nanocarriers with amphiphilic polymer polyethylene glycol (PEG), known as PEGylation, is regarded as a major breakthrough in the application of nanocarriers. However, PEGylated nanocarriers (including liposomes and polymeric nanoparticles) induce what is referred to as the "accelerated blood clearance (ABC) phenomenon" upon repeated injection and consequently they lose their sustained circulation characteristics. Despite this, the present authors are not aware of any reports of accelerated clearance due to repeated injection for PEGylated solid lipid nanoparticles (SLNs), another promising nanocarrier. This study investigated the pharmacokinetics of PEGylated SLNs upon repeated administration in mice; moreover, the impact of circulation time on the induction of the ABC phenomenon was studied in beagles for the first time. The ABC index, selected as the ratio of the area under the concentration-time curve from time 0 to the last measured concentration of a second injection to that of the first injection, was used to evaluate the extent of this phenomenon. Results showed that the PEGylated SLNs exhibited accelerated clearance from systemic circulation upon repeated injection, both in mice and in beagles, and the ratio for the different time intervals, which showed that the ABC index exhibited significant difference within 30 minutes following the second injection, was good enough to evaluate the magnitude of ABC. This ABC index indicated that the 10 mol% PEG SLNs with a suitable prolonged circulation time induced the most marked ABC phenomenon in this research. This study demonstrated that, like PEGylated nanocarriers such as liposomes and polymeric nanoparticles, PEGylated SLNs induced the ABC phenomenon upon repeated injection--the beagle was a valuable experimental animal for this research. Furthermore, the authors considered that a relatively extended circulation time of the initial dose may be the underlying major factor determining the induction of the ABC phenomenon.