Surface Gradient Desodiation Chemistry in Layered Oxide Cathode Materials.

Sodium-ion batteries (SIBs) as a promising technology for large-scale energy storage have received unprecedented attention. However, the cathodes in SIBs generally suffer from detrimental cathode-electrolyte interfacial side reactions and structural degradation during cycling, which leads to severe capacity fade and voltage decay. Here, we have developed an ultra-stable Na0.72Ni0.20Co0.21Mn0.55Mg0.036O2 (NCM-CS-GMg) cathode material in which a Mg-free core is encapsulated by a shell with gradient distribution of Mg using coprecipitation method with Mg-hysteretic cascade feedstock followed by calcination. From the interior to outer surface of the shell, as the content of electrochemically inactive Mg gradually increases, the Na+ deintercalation amount gradually decreases after charged. Benefiting from this surface gradient desodiation, the surface transition metal (TM) ion migration from TM layers to Na layers is effectively inhibited, thus suppressing the layered-to-rock-salt phase transition and the resultant microcracks. Besides, the less formation of high-valence TM ions on the surface contributes to a stable cathode-electrolyte interface. The as-prepared NCM-CS-GMg exhibits remarkable cycling life over 3000 cycles with a negligible voltage drop (0.127 mV per cycle). Our findings highlight an effective way to developing sustainable cathode materials without compromising on the initial specific capacity for SIBs.

Validation of the Chinese Version of the Relevant Outcome Scale for Alzheimer's Disease (CROSA).

OBJECTIVES: To examine the psychometric properties of the Chinese version of the Relevant Outcome Scale for Alzheimer's disease (CROSA) among persons with AD (PWAD) and their caregivers in China. DESIGN: A single-arm, open-label, multi-center study. SETTING: Two tertiary general hospitals in Shanghai. PARTICIPANTS: A total of 336 PWAD and their family caregivers. INTERVENTION: The PWAD completed a 12-week treatment with memantine after a baseline assessment. MEASUREMENTS: The CROSA and the Chinese versions of the Mini-Mental State Examination, the Alzheimer's Disease Assessment Scale-Cognitive Subscale, the Disability Activity of Dementia, the Neuropsychiatric Inventory Questionnaire, the Zarit Caregiver Burden Interview and the Self-Efficacy Questionnaire for Chinese Family Caregivers. RESULTS: The Cronbach's alpha for the total scale was 0.900, and the intraclass correlation coefficient and Pearson's correlation coefficient were 0.910 (P < 0.001) and 0.836 (P < 0.001), respectively. Confirmatory factor analysis revealed the two-factor model to be consistent with the original version. For the known-group validity, the total score of the CROSA classified the PWAD into three stages and three MMSE score groups. Moderate to large correlations with the validated scales confirmed the criteria validity of the CROSA, and the convergent validity was confirmed via testing a hypothesized caregiving model; however, only minimal responsiveness was found among the deterioration group after 12 weeks of treatment with memantine. CONCLUSIONS: The reliability and validity of the CROSA was good or acceptable for use in daily clinical settings. Further studies are needed to examine the psychometric properties of the scale.

The development of a behaviour questionnaire for stoma self-management for persons with bladder cancer and an ileal conduit.

AIMS: To develop and preliminarily test the reliability and validity of a behaviour questionnaire for stoma self-management for patients with bladder cancer after radical cystectomy and ileal conduit. DESIGN: A psychometric instrument validation study conducted in two phases. METHODS: The initial version of behaviour questionnaire was developed based on guidelines for people living with a stoma. Five experts validated the content of the preliminary 29-item questionnaire. A cross-sectional survey was then conducted in Beijing for preliminary reliability and validity tests between 4 December 2017-28 April 2018. A total of 151 participants in the survey, 147 of whom completed the study and 16 completed a 2-week test-retest reliability test. RESULTS: The content validity indices were satisfied. A principal component analysis with direct oblimin rotation was performed. Sixteen items were retained, and three factors were identified, namely, pouching system change, emotional management, and role management. The 16-item questionnaire showed acceptable internal consistency and test-retest reliability. The mediational effect of self-management behaviour on the relationship between self-efficacy and stoma quality of life was confirmed via convergent validity testing. CONCLUSION: The behaviour questionnaire for stoma self-management appears to have adequate initial reliability and validity. More observational and interventional studies need to be conducted for further evaluation of its psychometric properties. IMPACT: This study developed a reliable instrument to measure self-management behaviours for persons living with a stoma after radical cystectomy and ileal conduit. The questionnaire has practical value for both healthcare providers and researchers working in this field. The 16-item questionnaire can be administered quickly in clinical practice. Based on the questionnaire and the elicited mediational model, psycho-education programs tailored to improve self-management should be designed, implemented, and re-inspected regarding their effectiveness for the target population in China.

Heat-treated emulsions with cross-linking bovine serum albumin interfacial films and different dextran surfaces: effect of paclitaxel delivery.

In this study, a type of biocompatible and biodegradable oil-in-water emulsion for hydrophobic drug delivery was evaluated in vitro and in vivo. Bovine serum albumin (BSA)-dextran conjugates with different dextran molecular weights and different conjugation degrees were used as the emulsifier and stabilizer. Paclitaxel (PTX), a hydrophobic antitumor drug, was effectively loaded inside the oil droplets via high-pressure homogenization. The emulsions were heated at 90°C for 1 h to eliminate the anaphylaxis of BSA. By virtue of the cross-linked BSA films at the oil-water interfaces produced by the heat treatment and the hydrophilic dextran surfaces, the emulsions are stable in blood serum, as well as stable against long-term storage. In vitro cytotoxicity study verifies that the unloaded emulsions are biocompatible and the PTX-loaded emulsions have similar antitumor activity as PTX solution. In vivo investigation of murine ascites hepatoma H22-tumor-bearing mice demonstrates that the PTX-loaded emulsion with shorter and denser dextran surface has better tumor inhibition and survivability efficacy than the commercial PTX injection.

Amphiphilic cholic-acid-modified dextran sulfate and its application for the controlled delivery of superoxide dismutase.

A novel amphiphilic and biodegradable polyelectrolyte DS-CA is prepared by the esterification of DS with CA. DS-CA can self-assemble into stable nanoparticles in water. SOD can effectively associate with DS-CA at pH = 5.0 by virtue of electrostatic and hydrophobic interactions. SOD release from the complex nanoparticles is slow at pH = 1.2. The release at pH = 7.4 PBS shows an extended behavior and is tunable by changing the weight ratio of SOD to DS-CA as well as the CA substitution degree. Increasing the CA substitution degree of DS-CA can significantly enhance the cellular uptake of the loaded SOD. This study demonstrates that the amphiphilic DS-CA provides a promising strategy for oral delivery of protein/peptide drugs.

Nanoparticles with dextran/chitosan shell and BSA/chitosan core--doxorubicin loading and delivery.

Biocompatible bovine serum albumin (BSA)-dextran-chitosan nanoparticles were fabricated by heating the mixture of chitosan and BSA-dextran conjugates by virtue of the electrostatic attraction between BSA and chitosan as well as the gelation of BSA. The BSA-dextran conjugates were prepared by Maillard reaction. The nanoparticles were characterized by light scattering, zeta-potential, atomic force microscopy and pyrene fluorescence. The nanoparticles having a spherical shape and hydrodynamic diameters of 130-230 nm are stable in physiological condition. Doxorubicin can be effectively loaded into the nanoparticles after changing the pH of their mixture to 7.4 by virtue of the electrostatic and hydrophobic interactions between the nanoparticles and doxorubicin. The antitumor effects of doxorubicin loaded nanoparticles were investigated by the tumor inhibition and survivability of murine ascites hepatoma H22 tumor-bearing mice. The loaded nanoparticles can largely decrease the toxicity of doxorubicin and significantly increase the survivability of the tumor-bearing mice.