Mesenchymal stem cell (MSC) implantation has emerged as a potential therapy for myocardial infarction (MI). However, the poor survival of MSCs implanted to treat MI has significantly limited the therapeutic efficacy of this approach. This poor survival is primarily due to reactive oxygen species (ROS) generated in the ischemic myocardium after the restoration of blood flow. ROS primarily causes the death of implanted MSCs by inhibiting the adhesion of the MSCs to extracellular matrices at the lesion site (i.e., anoikis). In this study, we proposed the use of graphene oxide (GO) flakes to protect the implanted MSCs from ROS-mediated death and thereby improve the therapeutic efficacy of the MSCs. GO can adsorb extracellular matrix (ECM) proteins. The survival of MSCs, which had adhered to ECM protein-adsorbed GO flakes and were subsequently exposed to ROS in vitro or implanted into the ischemia-damaged and reperfused myocardium, significantly exceeded that of unmodified MSCs. Furthermore, the MSC engraftment improved by the adhesion of MSCs to GO flakes prior to implantation enhanced the paracrine secretion from the MSCs following MSC implantation, which in turn promoted cardiac tissue repair and cardiac function restoration. This study demonstrates that GO can effectively improve the engraftment and therapeutic efficacy of MSCs used to repair the injury of ROS-abundant ischemia and reperfusion by protecting implanted cells from anoikis.

Electrophysiological phenotype development and paracrine action of mesenchymal stem cells (MSCs) are the critical factors that determine the therapeutic efficacy of MSCs for myocardial infarction (MI). In such respect, coculture of MSCs with cardiac cells has windowed a platform for cardiac priming of MSCs. Particularly, active gap junctional crosstalk of MSCs with cardiac cells in coculture has been known to play a major role in the MSC modification through coculture. Here, we report that iron oxide nanoparticles (IONPs) significantly augment the expression of connexin 43 (Cx43), a gap junction protein, of cardiomyoblasts (H9C2), which would be critical for gap junctional communication with MSCs in coculture for the generation of therapeutic potential-improved MSCs. MSCs cocultured with IONP-harboring H9C2 (cocultured MSCs: cMSCs) showed active cellular crosstalk with H9C2 and displayed significantly higher levels of electrophysiological cardiac biomarkers and a cardiac repair-favorable paracrine profile, both of which are responsible for MI repair. Accordingly, significantly improved animal survival and heart function were observed upon cMSC injection into rat MI models compared with the injection of unmodified MSCs. The present study highlights an application of IONPs in developing gap junctional crosstalk among the cells and generating cMSCs that exceeds the reparative potentials of conventional MSCs. On the basis of our finding, the potential application of IONPs can be extended in cell biology and stem cell-based therapies.

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Background Studies reported the relationship between behavioural and psychological symptoms of dementia (BPSD), cognitive function, caregiver burden, and therapeutic effects. However, the causal relationship between BPSD in community-dwelling patients with Alzheimer’s disease (AD) and caregiver burden is yet to be established. This study aimed to classify BPSD in patients with AD and identify the relationship between BPSD and the factors affecting family caregiver burden. Methods Path analysis was conducted at a neurology outpatient clinic of a tertiary general hospital in South Korea. The medical records of 170 patients, aged ≥50 years, diagnosed with or suspected for AD were retrospectively reviewed. We investigated cognitive function (Korean version of the Mini-Mental-State Exam), dementia stages (Korean version of the Expanded Clinical Dementia Rating scale), depression (Short-form Geriatric Depression Scale-Korea), activities of daily living (ADL; Korean version of the Barthel Activities of Daily Living index), instrumental activities of daily living (IADL; Seoul-Instrumental Activities of Daily Living), and BPSD and caregiver burden (Korean Neuropsychiatric Inventory). Considering the characteristic features of BPSD with various symptoms, BPSD was classified using factor analysis. Factor extraction was performed using principal component analysis, followed by Varimax factor rotation. Results Mean total BPSD score was 17.66 ± 20.67, and the mean score for family caregiver burden was 9.65 ± 11.12. Symptom cluster-1 (hyperactivity symptoms) included disinhibition, irritability, and agitation/aggression. Symptom cluster-2 (psychosis symptoms) included hallucinations, anxiety, elation/euphoria, delusions, and depression/dysphoria. Symptom cluster-3 (physical behaviour symptoms) included appetite and eating abnormalities, apathy/indifference, aberrant motor behaviour, sleep, and night-time behaviour disturbances. Dementia stages, ADL, and IADL had indirect effects on family caregiver burden through hyperactivity, psychosis, and physical behaviour symptoms, indicating that BPSD exerted a complete mediating effect. Conclusions Unlike previous studies, we classified BPSD symptoms into similar symptom clusters to evaluate its effect on caregiver burden, rather than collectively investigating the 12 symptoms of BPSD. As the dementia stage worsens, symptom clusters in BPSD serve as a medium between ADL and IADL degradation and for the increase in caregivers’ burden. The development and implementation of therapeutic, nursing interventions, and policies focusing on dementia stages, ADL, and IADL, delaying and preventing BPSD can alleviate family caregivers’ burden.

Background and objectivesThis study was conducted to measure the level of health-related quality of life (HRQOL) and to reveal the association of self-efficacy and treatment satisfaction with it in Korean dialysis patients.Design, setting, participants, and measurementsThe study subjects were 237 patients receiving either hemodialysis (HD) or peritoneal dialysis (PD) from two university hospitals, from February to June in 2010. We investigated HRQOL using the Korean version of Kidney Disease Quality of Life Short Form 36 (KDQOL-36), and self-efficacy and treatment satisfaction by self-administrative questionnaire and their dialysis-related variables by reviewing clinical records. The associations of self-efficacy and treatment satisfaction with HRQOL were assessed using multiple linear regression analysis.ResultsThe mean HRQOL results were as follows: Physical component score (PCS) was 39.1 ± 8.5, Mental component score (MCS) 44.6 ± 6.8, symptom/problem list was 67.6 ± 17.1, effects of disease score was 58.5 ± 19.6, and burden of disease score was 41.1 ± 28.4. Between PD and HD patients, we could find significant difference only in the symptom/problem list. After removing confounder’s effects by multivariate analysis, respectively, treatment goal self-efficacy and treatment management self-efficacy were significantly related with all 5 domains, except PCS. Treatment satisfaction was significantly related with PCS, MCS, and effects of kidney disease.ConclusionsPatients’ self-efficacy and treatment satisfaction could influence their HRQOL. Regular and systematic monitoring using KDQOL-36 and interventions to increase self-efficacy and treatment satisfaction should be considered in dialysis care in Korea.