Mutagenicity and Genotoxicity Assessment of Leuconostoc lactis DMLL10 Isolated from Kimchi.

Leuconostoc lactis DMLL10 is a microorganism specific to kimchi fermentation. In this study, we sought to evaluate the toxicity of this strain, which was newly isolated from kimchi, to determine its safety as a food ingredient. Bacterial reverse mutation assay, chromosomal aberration assay, and mammalian cell in vitro micronucleus assay were performed to assess the genetic toxicity of Leu. lactis DMLL10. The strain did not induce mutagenicity in Salmonella typhimurium TA98, TA100, TA1535, TA1537, or Escherichia coli WP2uvrA, with or without metabolic activation of S9 mixture. The oral administration of Leu. lactis DMLL10 also did not significantly increase the number of micronucleated polychromatic erythrocytes, or the mean ratio of polychromatic to total erythrocytes. Additionally, Leu. lactis DMLL10 did not cause a significant chromosomal aberration in CHU/IL cells in the presence or absence of S9 activation. Therefore, Leu. lactis DMLL10 can be suggested as a functional food ingredient with reliability and safety.

Effects of Future Subjective Expectations on Cognitive Decline and Dementia among Middle-Aged and Older Adults.

This study investigated the impact of subjective expectations of the future (e.g., income, life expectancy, and national policies) on the onset of dementia and mild cognitive impairment by sex and age in middle-aged and older adults. The Korean Longitudinal Study of Aging (KLoSA) data from 2008 to 2020, comprising 4116 people above 45 years, were used. A time-series analysis and multiple panel logistic regression were conducted to highlight subjective expectation trends and their effect on dementia and mild cognitive impairment, respectively. Low subjective expectations of the future negatively affected cognitive impairment (total: odds ratio [OR] = 1.02, 95% confidence interval [CI] = 1.01-1.03) and dementia (total: OR = 1.05, 95% CI = 1.03-1.06), and those of national policies were the biggest risk factors for cognitive impairment (total: OR = 1.17, 95% CI = 1.12-1.22) and dementia (total: OR = 1.10, 95% CI = 1.07-1.13). Individuals about to retire and with low expectations of workability were more likely to develop cognitive impairment (total: OR = 1.03, 95% CI = 1.02-1.06). Subjective expectations of economic downturn also caused cognitive impairment, especially in women (OR = 1.04, 95% CI = 1.01-1.07) and early stage older adults (OR = 1.06, 95% CI = 1.02-1.10). Policymakers must consider the impact of changes in national policies and living environments on cognitive impairment and dementia in older adults.

Histopathologic image-based deep learning classifier for predicting platinum-based treatment responses in high-grade serous ovarian cancer.

Platinum-based chemotherapy is the cornerstone treatment for female high-grade serous ovarian carcinoma (HGSOC), but choosing an appropriate treatment for patients hinges on their responsiveness to it. Currently, no available biomarkers can promptly predict responses to platinum-based treatment. Therefore, we developed the Pathologic Risk Classifier for HGSOC (PathoRiCH), a histopathologic image-based classifier. PathoRiCH was trained on an in-house cohort (n = 394) and validated on two independent external cohorts (n = 284 and n = 136). The PathoRiCH-predicted favorable and poor response groups show significantly different platinum-free intervals in all three cohorts. Combining PathoRiCH with molecular biomarkers provides an even more powerful tool for the risk stratification of patients. The decisions of PathoRiCH are explained through visualization and a transcriptomic analysis, which bolster the reliability of our model's decisions. PathoRiCH exhibits better predictive performance than current molecular biomarkers. PathoRiCH will provide a solid foundation for developing an innovative tool to transform the current diagnostic pipeline for HGSOC.

Federated learning with knowledge distillation for multi-organ segmentation with partially labeled datasets.

The state-of-the-art multi-organ CT segmentation relies on deep learning models, which only generalize when trained on large samples of carefully curated data. However, it is challenging to train a single model that can segment all organs and types of tumors since most large datasets are partially labeled or are acquired across multiple institutes that may differ in their acquisitions. A possible solution is Federated learning, which is often used to train models on multi-institutional datasets where the data is not shared across sites. However, predictions of federated learning can be unreliable after the model is locally updated at sites due to 'catastrophic forgetting'. Here, we address this issue by using knowledge distillation (KD) so that the local training is regularized with the knowledge of a global model and pre-trained organ-specific segmentation models. We implement the models in a multi-head U-Net architecture that learns a shared embedding space for different organ segmentation, thereby obtaining multi-organ predictions without repeated processes. We evaluate the proposed method using 8 publicly available abdominal CT datasets of 7 different organs. Of those datasets, 889 CTs were used for training, 233 for internal testing, and 30 volumes for external testing. Experimental results verified that our proposed method substantially outperforms other state-of-the-art methods in terms of accuracy, inference time, and the number of parameters.

A Phase II Open-Label Randomized Clinical Trial of Preoperative Durvalumab or Durvalumab plus Tremelimumab in Resectable Head and Neck Squamous Cell Carcinoma.

PURPOSE: Clinical implications of neoadjuvant immunotherapy in patients with locally advanced but resectable head and neck squamous cell carcinoma (HNSCC) remain largely unexplored. PATIENTS AND METHODS: Patients with resectable HNSCC were randomized to receive a single dose of preoperative durvalumab (D) with or without tremelimumab (T) before resection, followed by postoperative (chemo)radiotherapy based on multidisciplinary discretion and 1-year D treatment. Artificial intelligence (AI)-powered spatial distribution analysis of tumor-infiltrating lymphocytes and high-dimensional profiling of circulating immune cells tracked dynamic intratumoral and systemic immune responses. RESULTS: Of the 48 patients enrolled (D, 24 patients; D+T, 24 patients), 45 underwent surgical resection per protocol (D, 21 patients; D+T, 24 patients). D±T had a favorable safety profile and did not delay surgery. Distant recurrence-free survival (DRFS) was significantly better in patients treated with D+T than in those treated with D monotherapy. AI-powered whole-slide image analysis demonstrated that D+T significantly reshaped the tumor microenvironment toward immune-inflamed phenotypes, in contrast with the D monotherapy or cytotoxic chemotherapy. High-dimensional profiling of circulating immune cells revealed a significant expansion of T-cell subsets characterized by proliferation and activation in response to D+T therapy, which was rare following D monotherapy. Importantly, expansion of specific clusters in CD8+ T cells and non-regulatory CD4+ T cells with activation and exhaustion programs was associated with prolonged DRFS in patients treated with D+T. CONCLUSIONS: Preoperative D±T is feasible and may benefit patients with resectable HNSCC. Distinct changes in the tumor microenvironment and circulating immune cells were induced by each treatment regimen, warranting further investigation.

Immuno-Enhancing Effects of Galium aparine L. in Cyclophosphamide-Induced Immunosuppressed Animal Models.

This study investigates the immunomodulatory potential of Galium aparine L. (GAE) in immunodeficient animals. In this study, animals were categorized into five groups: the normal group, CYP group (cyclophosphamide intraperitoneal injection), GA5 group (cyclophosphamide + 5 µg GAE), GA50 group (cyclophosphamide + 50 µg GAE), and GA500 group (cyclophosphamide + 500 µg GAE). The CYP group exhibited significantly reduced spleen weights compared to the normal group, while the groups obtaining GAE displayed a dose-dependent increase in spleen weight. Furthermore, the GAE demonstrated dose-dependent enhancement of splenocyte proliferating activity, with significant increases observed in both LPS and ConA-induced assays. NK cell activity significantly increased in the GA50 and GA500 groups compared to the CYP group. Cytokine analysis revealed a significant increase in IL-6, TNF-α, and IFN-γ levels in ConA-induced splenocytes treated with GAE. Gene expression analysis identified 2434 DEG genes in the extract groups. Notable genes, such as Entpd1, Pgf, Thdb, Syt7, Sqor, and Rsc1al, displayed substantial differences in individual gene expression levels, suggesting their potential as target genes for immune enhancement. In conclusion, Galium aparine L. extract exhibits immunomodulatory properties. The observed gene expression changes further support the potential of Galium aparine L. extract as a natural agent for immune augmentation.

Effects of physical activity participation on cognitive impairment in older adults population with disabilities.

Background: Existing research on the association between cognitive function and physical activity in the older adults population with disabilities is limited. Additionally, there is a need to explore avenues for enhancing the longevity and quality of life among these individuals. Objective: This study aimed to investigate the independent and joint associations between cognitive function and levels of physical activity in the older adults population with disabilities. Methods: A total of 315 older adults adults (men = 182, women = 133), identified with disabilities based on medical evaluation, were recruited from the first survey of the Korean Longitudinal Study of Aging (KLoSA). Participants underwent assessments for cognitive function, physical activity (PA), activities of daily living (ADLs), instrumental activities of daily living (IADLs), and grip strength. Results: ADLs (p < 0.001) and IADLs (p < 0.001) scores were significantly higher in the male normal cognitive group compared to both the male and female cognitive impairment groups. In an unadjusted model, disabled older adults individuals who did not meet the recommended PA guidelines showed an increased odds ratio for cognitive dysfunction (OR = 2.29, 95% CI = 1.32-3.97). Those participating in PA at least 1 day per week also demonstrated an elevated odds ratio (OR = 1.22, 95% CI = 1.08-1.38) for cognitive dysfunction compared to those who engaged in regular PA. A negative correlation was observed between K-MMSE scores and grip strength (r = 0.448, p < 0.001). Conclusion: This study provides robust evidence that disabled older adults individuals who do not meet the recommended guidelines for PA or who do not participate in PA at least once a week have an increased likelihood of cognitive impairment compared to those who are regularly active.

The development of self- and group orientations among Chinese young adolescents: Implications for social and behavioral adjustment.

Self- and group orientations represent distinct ways of perceiving the relations between the world and the self and are relevant to adolescents' development. Most of the existing studies in this area are cross-sectional, providing little information about how self- and group orientations develop. This 3-year longitudinal study examined the developmental patterns of self- and group orientations and their relations with adjustment among Chinese adolescents. The participants included 1,257 students (648 boys, initial Mage = 13.37 years, SD = 0.63 years). Data on self- and group orientations and social and behavioral adjustment were obtained from multiple sources, including self-reports, peer nominations, and teacher ratings. The results showed that self-orientation increased, and group orientation decreased during early adolescence. Moreover, an increase (slope) in self-orientation was positively associated with subsequent assertive behavior, whereas a slower decrease in group orientation was positively associated with subsequent prosocial behavior and peer preference. The initial level (intercept) of self-orientation was positively associated with later externalizing problems, and the initial level of group orientation was negatively associated with later internalizing problems. The intercepts of self- and group orientations were higher for boys than girls. No significant gender differences were found in the slopes of self- and group orientations or in the associations of intercepts and slopes with adjustment outcomes. The results indicated different developmental patterns of self- and group orientations and their different implications for adjustment in Chinese adolescents. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Factors predicting different times for brushing teeth during the day: multilevel analyses.

BACKGROUND: The most effective and simple intervention for preventing oral disease is toothbrushing. However, there is substantial variation in the timing of brushing teeth during the day. We aimed to identify a comprehensive set of predictors of toothbrushing after lunch and after dinner and estimated contextual (i.e., geographic) variation in brushing behavior at different times of the day. METHODS: We constructed a conceptual framework for toothbrushing by reviewing health behavior models. The main data source was the 2017 Community Health Survey. We performed a four-level random intercept logistic regression to predict toothbrushing behavior. (individual, household, Gi/Gun/Gu, and Si/Do). RESULTS: Individuals under 30 years of age had higher likelihood of brushing after lunch, while brushing after dinner was higher among those aged 40-79 years. People engaged in service/sales, agriculture/fishing/labor/mechanics, as well as student/housewife/unemployed were 0.60, 0.41, and 0.49 times less likely to brush their teeth after lunch, respectively, compared to those working in the office, but the gap narrowed to 0.97, 0.96, 0.94 for brushing after dinner. We also found significant area-level variations in the timing of brushing. CONCLUSIONS: Different patterns in association with various factors at individual-, household- and Si/Gun/Gu-levels with toothbrushing after lunch versus toothbrushing after dinner suggests a need for tailored interventions to improve toothbrushing behavior depending on the time of day.

Novel Strain Leuconostoc lactis DMLL10 from Traditional Korean Fermented Kimchi as a Starter Candidate for Fermented Foods.

Leuconostoc lactis strain DMLL10 was isolated from kimchi, a fermented vegetable, as a starter candidate through safety and technological assessments. Strain DMLL10 was susceptible to ampicillin, chloramphenicol, clindamycin, erythromycin, gentamicin, kanamycin, streptomycin, and tetracycline. It did not show any hemolytic activity. Regarding its phenotypic results related to its safety properties, genomic analysis revealed that strain DMLL10 did not encode for any toxin genes such as hemolysin found in the same genus. It did not acquire antibiotic resistance genes either. Strain DMLL10 showed protease activity on agar containing NaCl up to 3%. The genome of DMLL10 encoded for protease genes and possessed genes associated with hetero- and homo-lactic fermentative pathways for lactate production. Finally, strain DMLL10 showed antibacterial activity against seven common foodborne pathogens, although bacteriocin genes were not identified from its genome. These results indicates that strain DMLL10 is a novel starter candidate with safety, enzyme activity, and bacteriocin activity. The complete genomic sequence of DMLL10 will contribute to our understanding of the genetic basis of probiotic properties and allow for assessment of the effectiveness of this strain as a starter or probiotic for use in the food industry.

Novel Starter Strain Enterococcus faecium DMEA09 from Traditional Korean Fermented Meju.

The Enterococcus faecium strain DMEA09 was previously isolated from traditional Korean fermented meju. The objective of the current study was to investigate the traits of E. faecium strain DMEA09 as a starter candidate, focusing on its safety and technological properties. Regarding its safety, the DMEA09 strain was found to be sensitive to nine antibiotics (ampicillin, chloramphenicol, erythromycin, gentamicin, kanamycin, streptomycin, tetracycline, tylosin, and vancomycin) by showing lower minimum inhibitory concentrations (MICs) than the cut-off values suggested by the European Union Food Safety Authority for these nine antibiotics. However, its MIC value for clindamycin was twice as high as the cut-off value. A genomic analysis revealed that strain DMEA09 did not encode the acquired antibiotic resistance genes, including those for clindamycin. The DMEA09 strain did not show hemolysis as a result of analyzing α- and ß-hemolysis. It did not form biofilm either. A genomic analysis revealed that strain DMEA09 did not encode for any virulence factors including hemolysin. Most importantly, multilocus sequence typing revealed that the clonal group of strain DMEA09 was distinguished from clinical isolates. Regarding its technological properties, strain DMEA09 could grow in the presence of 6% salt. It showed protease activity when the salt concentration was 3%. It did not exhibit lipase activity. Its genome possessed 37 putative protease genes and salt-tolerance genes for survivability under salt conditions. Consequently, strain DMEA09 shows safe and technological properties as a new starter candidate. This was confirmed by genome analysis.

Reduction of Osteoclastic Differentiation of Raw 264.7 Cells by EMF Exposure through TRPV4 and p-CREB Pathway.

In this study, we investigated the effect of EMF exposure on the regulation of RANKL-induced osteoclast differentiation in Raw 264.7 cells. In the EMF-exposed group, the cell volume did not increase despite RANKL treatment, and the expression levels of Caspase-3 remained much lower than those in the RANKL-treated group. TRAP and F-actin staining revealed smaller actin rings in cells exposed to EMF during RANKL-induced differentiation, indicating that EMF inhibited osteoclast differentiation. EMF-irradiated cells exhibited reduced mRNA levels of osteoclastic differentiation markers cathepsin K (CTSK), tartrate-resistant acid phosphatase (TRAP), and matrix metalloproteinase 9 (MMP-9). Furthermore, as measured by RT-qPCR and Western blot, EMF induced no changes in the levels of p-ERK and p-38; however, it reduced the levels of TRPV4 and p-CREB. Overall, our findings indicate that EMF irradiation inhibits osteoclast differentiation through the TRPV4 and p-CREB pathway.

Baltimore pediatric ocular trauma study: Health disparities and outcomes in pediatric and adolescent open globe trauma.

Purpose Children represent approximately one-third of patients with serious ocular injuries. Our study evaluates associations between race and socioeconomic status in presentation and outcomes of pediatric and adolescent traumatic open globe injuries. Methods We conducted a retrospective chart review of traumatic open globe injuries in pediatric and adolescent patients presenting to Johns Hopkins Hospital and University of Maryland Medical Center between 2006 and 2020. Variables assessed included age, gender, parent-identified race, median household income, mechanism of injury, initial and final visual acuity (VA), and length of follow-up. Results Eighty patients ranging from 4 months to 17.7 years (mean 9.3 years) presented with traumatic open globe injury. Identifications were 28 White (35%), 38 Black (48%), and 5 Hispanic (6%). Initial presenting and final VA, pediatric ocular trauma score (POTS), and length of follow-up did not differ significantly among race, gender, or income. Black patients had higher rates of blunt trauma (odds ratio (OR) 3.81; 95% confidence interval (CI) 0.95-15.24, p = 0.07), uveal prolapse (OR 3.58; 95% CI 1.03-12.43; p = 0.049), and enucleation (OR 10.55; 95% CI 1.26-88.31). Hispanic patients presented at a younger age of 2.8 years mean age vs. 9.9 years (p = 0.004) for others. Conclusion Visual outcomes following traumatic open globe injury were independent of race, gender, or income. However, blunt trauma, uveal prolapse, and enucleation rates were higher in Black patients, and ocular trauma occurred at a younger age in Hispanic patients.

Stability Enhancement of Freeze-Dried Gelatin/Alginate Coacervates for bFGF Delivery.

Chronic wound sites have elevated levels of proteolytic enzymes that negate the activity of topically applied growth factors. bFGF encapsulated in gelatin/alginate coacervates was protected from protease and showed better activity than bFGF in solution; however, its activity decreased with particle size and PDI increase after freeze-drying and rehydration. In this study, we aim to improve the stability of bFGF coacervates during freeze-drying to enable a topically applied growth factor delivery system for diabetic foot ulcer. Trehalose, mannitol, and Tween 80 at various concentrations were tested as cryoprotectant candidates. Trehalose improved the mechanical property of freeze-dried coacervates and physical properties after rehydration, resulting in stable size and PDI values. It also enhanced the bFGF activity in hyperglycemic human dermal fibroblasts with better cell viability, migration, and procollagen synthesis compared to the coacervates without trehalose. Hydrogen bonding interactions between trehalose and polymers probed by ATR-FTIR contribute to the stability of coacervates during freeze-drying. In conclusion, the freeze-dried gelatin/alginate coacervates encapsulating bFGF was effectively stabilized with trehalose, and the resulting coacervate composition is suggested as a potential therapeutic modality for chronic wounds including diabetic foot ulcer.

Relationship between Precarious Employment and Unmet Dental Care Needs among Korean Workers: A Longitudinal Panel Study.

Background and Objectives: Precarious workers experience certain conditions, such as low income, instability in employment, and lack of social security. Precarious employment has increased barriers to the use of dental care services, resulting in more unmet dental care needs. The aim of this study was to identify unmet dental care needs among precarious workers in Korea's labor market, using data from the Korea Health Panel Survey (2011-2017). Materials and Methods: Based on job and income security criteria, four groups were formed: Group A (individuals with job and income security), Group B (individuals reporting job security with income insecurity), Group C (individuals reporting job insecurity with income security), and Group D (individuals with job and income insecurity). We measured self-reported unmet dental need or the inability to receive necessary dental care owing to the past economic burdens. Panel logistic regression analyses were performed to determine the effect of precarious employment on unmet dental care needs for all participants. Results: Approximately 16% of the respondents reported having unmet dental care needs. Unmet dental care needs owing to economic reasons were higher among male workers in groups C and D than among male workers in Group A. In particular, male workers aged 50 years and above in Group B were 3.36 times more likely to have unmet dental care needs than those in Group A. In Group D, female workers showed a high probability of having dental care needs owing to economic reasons. Moreover, female workers aged 18-49 years witnessed an increase in unmet dental care needs. Conclusions: Korean workers with unstable employment and/or income are at a higher risk of having unmet dental care needs owing to financial factors. The findings suggest an urgent need to implement robust national health insurance policies to improve efforts aimed at reducing unmet dental care needs that potentially decreases the disparity in oral health among precariously employed workers. Furthermore, it is necessary to implement comprehensive labor market policies such as sickness benefits for those in precarious employment.

COVID-19 and Unmet Medical Needs for People With Chronic Diseases: A Cross-Sectional Study.

Gaps between medical needs and health services accessibility are defined as unmet medical needs (UMN). Previous studies assessing UMNs during the coronavirus disease 2019 (COVID-19) pandemic did not account for factors such as the type of medical insurance or chronic disease. Therefore, this study investigated various factors, including medical insurance and chronic diseases, affecting self-reported UMN during the pandemic in Daejeon Metropolitan City, South Korea. This cross-sectional study was conducted using Daejeon Metropolitan City Health Surveys data from 2020. The weighted prevalence of UMN was estimated among participants (n = 1494) aged ≥18 years, while chi-squared and logistic models were used to assess the association between UMN and participant characteristics. The prevalence of UMN was 6.4% (n = 97). Female sex and low education levels were significantly associated with reporting UMN. Medical aid beneficiaries were less likely to report UMN than adults with National Health Programs coverage. Participants with chronic diseases, such as hypertension and arthritis, and those with depression, were more likely to report UMN than adults without these conditions. The findings highlight the need for targeted efforts to decrease UMN in the COVID-19 pandemic, especially for women and individuals with low education levels. The results also indicate that high-risk disease groups should be targeted with additional enabling services to support the management of chronic conditions.

Safety Assessment Systems for Microbial Starters Derived from Fermented Foods.

Microorganisms involved in food fermentation not only improve the aroma and taste of the food, but also enhance its preservation. Thus, they are added as starter cultures to boost the final product quality of commercial fermented foods. Although these microorganisms originate from fermented foods and have a long history of consumption, the European Union recently applied the concept of Qualified presumption of Safety (QPS), which is a safety evaluation system for microorganisms used in food or feed in Europe. The QPS system is a species-level safety system and shares results with the European Novel Food System, a strain-level safety evaluation system. In the United States, microorganisms added to fermented foods are considered as food additives or Generally Recognized as Safe substance. In Korea, food microbe lists are presented at the species level. Moreover, the nation has established a strain-oriented evaluation system that applies temporary safety evaluation methods for food raw materials as well as new raw materials. However, when it comes to microorganisms isolated from traditional fermented foods and other fermented food products, there is no definition of the term "species," and there is a lack of an evaluation system at the species level. Therefore, such an evaluation system for microbial species used in Korean fermented foods is necessary.

Extremely Low-Frequency Electromagnetic Fields Increase Cytokines in Human Hair Follicles through Wnt/ß-Catenin Signaling.

Hair loss is a chronic disorder that affects many people; however, a complete treatment has not yet been developed. Therefore, new therapeutic agents for preventing hair loss must be developed, and electromagnetic field (EMF) therapy has been proven to be a promising medical treatment in various fields, including hair loss treatment. This study evaluated the effect of extremely low-frequency electromagnetic field (ELF-EMF) intensity and exposure time by analyzing the expression of cytokines and anagen-related molecules, which influence hair activation and growth, in hair bulb spheroid (HBS) and hair follicle (HF) organ cultures. ELF-EMFs did not induce toxicity in the HBSs, as verified via the lactate dehydrogenase (LDH) assay. Moreover, an ELF-EMF intensity of 5-20 G promoted the expression of ALP, versican, ß-catenin, and several cytokines (VEGF, PDGF, FGF-10, and ET-1) in HBSs. Immunohistochemical staining showed that ELF-EMF at an intensity of 5-20 G upregulated ALP and ß-catenin and decreased TUNEL staining in HBS. Moreover, HFs exposed to ELF-EMF for 60 min exhibited an increase in hair length and a 1.5-fold increase in IL-4, ICAM-1, ALP, and versican mRNA expression compared to the control. Immunohistochemical staining indicated that 60 min of ELF-EMF can increase the expression of ALP and ß-catenin and decreases TUNEL staining in organ cultures. Collectively, our results demonstrated that ELF-EMF exposure at a 10 G intensity for 60 min promoted hair shaft growth in HFs due to the effect of cytokines and adhesion molecules via the Wnt/ß-catenin pathway. Therefore, ELF-EMF is a promising treatment for hair loss.

Induction of PLXNA4 Gene during Neural Differentiation in Human Umbilical-Cord-Derived Mesenchymal Stem Cells by Low-Intensity Sub-Sonic Vibration.

Human umbilical-cord-derived mesenchymal stem cells (hUC-MSC) are a type of mesenchymal stem cells and are more primitive than other MSCs. In this study, we identify novel genes and signal-activating proteins involved in the neural differentiation of hUC-MSCs induced by Low-Intensity Sub-Sonic Vibration (LISSV). RNA sequencing was used to find genes involved in the differentiation process by LISSV. The changes in hUC-MSCs caused by LISSV were confirmed by PLXNA4 overexpression and gene knockdown through small interfering RNA experiments. The six genes were increased among genes related to neurons and the nervous system. One of them, the PLXNA4 gene, is known to play a role as a guide for axons in the development of the nervous system. When the PLXNA4 recombinant protein was added, neuron-related genes were increased. In the PLXNA4 gene knockdown experiment, the expression of neuron-related genes was not changed by LISSV exposure. The PLXNA4 gene is activated by sema family ligands. The expression of SEMA3A was increased by LISSV, and its downstream signaling molecule, FYN, was also activated. We suggest that the PLXNA4 gene plays an important role in hUC-MSC neuronal differentiation through exposure to LISSV. The differentiation process depends on SEMA3A-PLXNA4-dependent FYN activation in hUC-MSCs.

Induced Neurodifferentiation of hBM-MSCs through Activation of the ERK/CREB Pathway via Pulsed Electromagnetic Fields and Physical Stimulation Promotes Neurogenesis in Cerebral Ischemic Models.

Stroke is among the leading causes of death worldwide, and stroke patients are more likely to live with permanent disabilities even after treatment. Several treatments are being developed to improve the quality of life of patients; however, these treatments still have important limitations. Our study thus sought to evaluate the neural differentiation of human bone marrow mesenchymal stem cells (hBM-MSCs) at various pulsed electromagnetic field (PEMF) frequencies. Furthermore, the effects of selected frequencies in vivo were also evaluated using a mouse ischemia stroke model. Cell proliferation decreased by 20% in the PEMF group, as demonstrated by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay, and lactate dehydrogenase (LDH) secretion increased by approximately 10% in an LDH release assay. Fluorescence-activated cell sorting (FACS) analysis demonstrated that CD73 and CD105 were downregulated in the PEMF group at 60 Hz. Moreover, microtubule-associated protein 2 (MAP-2) and neurofilament light chain (NF-L) were upregulated in cell cultures at 60 and 75 Hz. To assess the effects of PEMF in vivo, cerebral ischemia mice were exposed to a PEMF at 60 Hz. Neural-related proteins were significantly upregulated in the PEMF groups compared with the control and cell group. Upon conducting rotarod tests, the cell/PEMF group exhibited significant differences in motor coordination at 13 days post-treatment when compared with the control and stem-cell-treated group. Furthermore, the cell and cell/PEMF group exhibited a significant reduction in the expression of matrix metalloproteinase-9 (MMP-9), tumor necrosis factor-alpha (TNF-α) and interferon-gamma (IFN-γ) in the induced ischemic area compared with the control. Collectively, our findings demonstrated that PEMFs at 60 and 75 Hz could stimulate hBM-MSCs neural differentiation in vitro, in addition to promoting neurogenesis to enhance the functional recovery process by reducing the post-stroke inflammatory reaction.