The positive association between internal migration and hospitalization among the older adults in China: Regional heterogeneity and chronic disease management.

Background: Post-retirement migrants are rapidly increasing in China, but the impact of internal migration on hospitalization among older adults remains under-researched. Understanding this impact is essential for health policies development and improvement. This study aims to identify the most vulnerable population, evaluate the association between migration and hospitalization, and discuss potential causes of the association. Methods: 14,478 older adults were extracted from the 2018 to 2019 Chinese Longitudinal Healthy Longevity Survey (CLHLS) database and divided into four groups according to migration experience and age at migration: non-migrants, pre-adulthood migrants, pre-retirement migrants, and post-retirement migrants. Post-retirement migrants were key research subjects. We employed Pearson's chi-square test to compare group differences in outcome and covariates, and multivariate logistic regression analysis to examine the association between migration and hospitalization by regions and chronic conditions. Results: Significant intergroup differences were observed in demographic characteristics, socioeconomic factors, health habits, and health-related factors. Post-retirement migrants displayed following characteristics: female predominance (61.6%; 1,472/2,391), tending toward urban areas (80.9%; 1,935/2,391), and the highest prevalence rate of chronic disease (46.7%; 1,116/2,391). Urban migrants in eastern China were more likely to be hospitalized (OR = 1.65; 95% CI: 1.27-2.15), especially those who were diagnosed with chronic disease (OR = 1.51; 95% CI: 1.04-2.19) or with unconfirmed chronic conditions (OR = 1.98; 95% CI: 1.36-2.89). Conclusions: Internal migration is associated with the hospitalization of post-retirement migrants moving to eastern China. Improved chronic disease management and early interventions might lower the hospitalization. Effective policies should be formulated to reduce the disparity in primary care services across China, thereby facilitating the access of migrants to these services.

Controlled drug release from ultrasound-visualized elastic eccentric microcapsules using different resonant modes.

Ultrasound controlled drug delivery and release has attracted increased attention for targeted delivery of drug. In this report, we present a strategy for targeted drug delivery by using ultrasound to image the location of drug carriers, as well as simultaneously controlling the release rate of drug from elastic eccentric microcapsules (EEMs), based on their mode shapes (MSs) and resonant natural frequencies (NFs). We prepared a series of EEMs with various diameters of inner spherical cavities using a microfluidic chip. The EEMs could be visualized by an ultrasound imaging system within a tissue mimic (i.e. phantom). Using theoretical modeling techniques, we investigated the effects of MSs and NFs on the resonant modes of EEMs. Guided by this modelling, we applied external ultrasonic stimuli at various levels of low frequency to regulate the release rate of Rhodamine 6G (R6G, as a model drug) from EEMs. To further demonstrate the control of drug release and evaluate the efficacy of the encapsulated drugs on cancer cells, we released an anticancer drug, doxorubicin hydrochloride (DOX), from the EEMs and tested the viability of cancer cells in vitro. The results show that this novel strategy holds great promise towards development of a controlled drug release system visualized and triggered by ultrasound.

Hierarchical Patterning of Cells with a Microeraser and Electrospun Nanofibers.

For tissue engineering applications, it is important to develop fabrication strategies for building models with controlled cell distributions in defined structures. Here, a simple, flexible approach (named the µ-eraser strategy) is developed to construct multicell micropatterns. This approach involves pressing a poly(dimethylsiloxane) stamp to erase cells growing on substrates, and seeding other types of cells. The pressing/seeding process can be conducted in any designed pattern at desired time point. In a proof of concept, multicell micropatterns of human lung adenocarcinoma epithelial A549 cells, murine fibroblast (FB) cells and murine osteoblast (OB) cells are achieved on Petri dishes and electrospun sheets. Besides forming multicell micropatterns, the cell orientation can be regulated by microstripes and alignment of nanofibers. On Petri dishes and random fiber sheets, FB and OB cells align along microstripes, while A549 cells do not. However, when growing on aligned fiber sheets, no matter whether solo-cultured or co-cultured, all cells in micropatterns orient along the fibers. Based on this technique, a platform is built up to investigate rates of cell migration and interinvasion under solo-culture and co-culture systems. It is believed that this µ-eraser strategy has promise for biological, pharmaceutical, and biomedical applications.

Hydrophilic Magnetochromatic Nanoparticles with Controllable Sizes and Super-high Magnetization for Visualization of Magnetic Field Intensity.

Hydrophilic Fe3O4 nanoparticles with controllable size and shape have been fabricated using a facile solvothermal approach followed by surface modification with polyacrylic acid (PAA). The nanoparticles form one-dimension photonic crystal structure under external magnetic field ranging from 29.6 to 459 G. The reflection peaks of formed photonic crystals cover the entire visible spectrum, which indicates a good magnetochromatic property and prospect of wide applications. The size and shape of Fe3O4 nanoparticles are controlled by changing the ratio between ethylene glycol and diethylene glycol. In the process of surface modification, PAA synthesized by free radical polymerization was chemisorbed onto the surface of Fe3O4 particles with the aid of Fe(3+) cations, which renders the particles well dispersed in aqueous solution with high thermo-stability. The Fe3O4 particles exhibit ferrimagnetism with a high saturation magnetization value of 88.0 emu/g. Both the high magnetization and the wide reflection spectrum under magnetic field make the magnetochromatic nanoparticles a promising material for visualization of the distribution of magnetic field intensity on microfluidic chips.