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Objectives: Confirm that stem cells from human exfoliated deciduous teeth‐derived exosomes (SHED‐exos) can limit inflammation‐triggered epithelial cell apoptosis and explore the molecular mechanism. Methods: SHED‐exos were injected into the submandibular glands (SMGs) of non‐obese diabetic (NOD) mice, an animal model of Sjögren's syndrome (SS). Cell death was evaluated by western blotting and terminal deoxynucleotidyl transferase‐mediated dUTP nick‐end labelling staining. Results: SHED‐exos treatment promoted the saliva flow rates of NOD mice, accompanied by decreased cleaved caspase‐3 levels and apoptotic cell numbers in SMGs. SHED‐exos inhibited autophagy, pyroptosis, NETosis, ferroptosis, necroptosis and oxeiptosis marker expression in SS‐damaged glands. Mechanistically, Kyoto Encyclopedia of Genes and Genomes analysis of exosomal miRNAs suggested that the rat sarcoma virus (RAS)/mitogen‐activated protein kinase kinase (MEK)/extracellular signal‐regulated kinase (ERK) pathway might play an important role. In vivo, the expression of Kirsten RAS, Harvey RAS, MEK1/2 and p‐ERK1/2 was upregulated in SMGs, and this change was blocked by SHED‐exos treatment. In vitro, SHED‐exos suppressed p‐ERK1/2 activation and increased cleaved caspase‐3 and apoptotic cell numbers, which were induced by IFN‐γ. Conclusion: SHED‐exos suppress epithelial cell death, which is responsible for promoting salivary secretion. SHED‐exos inhibited inflammation‐triggered epithelial cell apoptosis by suppressing p‐ERK1/2 activation, which is involved in these effects. [ABSTRACT FROM AUTHOR]

Soil acidification in tea plantations has become a key factor restricting the development of the tea industry. Biochar reduces soil acidity significantly and has good short-term effects of acidic soil improvement in tea plantation trials, but the duration of the effect and the long-term environmental effects of biochar are still unclear. In this study, the acidic tea plantation soil to which biochar was applied five years ago was studied. The biochar applied to the soil was separated and analyzed for surface elements, and the aluminum form of the soil was measured. The results showed that : (1) Five years after biochar was applied to the soil, the surface aluminum elements of biochar increased significantly, indicating that biochar had a certain degree of adsorption effect on aluminum in the soil; (2) the pH of tea plantation soil increased significantly; (3) the exchangeable aluminum [Al3+] and monohydroxy and dihydroxy aluminum [Al(OH)2+, Al(OH)2+] both had the potential to convert to colloidal aluminum [Al(OH)3], and this conversion reduced the content of reactive aluminum in the soil, thus increasing the soil pH and reducing the toxicity of aluminum to plants.

Evidence Level: 1 Technical Efficacy Stage: 3 [ABSTRACT FROM AUTHOR]

Background: Diagnosis of Alzheimer's disease (AD) was recently shifted from clinical to biological construct to reflect underlying neuropathological status, where amyloid deposition designated patients to the Alzheimer's continuum, and additional tau positivity represented AD. Objective: To investigate white matter (WM) alteration in the brain of patients in the Alzheimer's continuum. Methods: A total of 236 subjects across the clinical and biological spectra of AD were included and stratified by normal/abnormal (–/+) amyloid (A) and tau (T) status based on positron emission tomography results, yielding five groups: A–T–cognitively normal (CN), A+T–CN, A+T+ CN, A+T+ mild cognitive impairment, and A+T+ AD. WM alteration was measured by diffusion tensor imaging (DTI). Group differences, correlation of DTI measures with amyloid and tau, and diagnostic performance of such measures were evaluated. Results: Compared with A–T–CN, widespread WM alteration was observed in the Alzheimer's continuum, including hippocampal cingulum (CGH), cingulum of the cingulate gyrus, and uncinate fasciculus. Diffusion changes measured by regional mean fractional anisotropy (FA) in the bilateral CGH were first detected in the A+T+ CN group and associated with tau burden in the Alzheimer's continuum (p < 0.001). For discrimination between A+T+ CN and A–T–CN groups, CGH FA achieved accuracy, sensitivity, and specificity of 74%, 58%, and 78% for right CGH and 57%, 83%, and 47% respectively for left CGH. Conclusion: WM alteration is widespread in the Alzheimer's continuum. Diffusion alteration in CGH occurred early and was correlated with tau pathology, thus may be a promising biomarker in preclinical AD. [ABSTRACT FROM AUTHOR]