UNASSIGNED: Because Alzheimer\'s disease (AD) has significant heterogeneity in encephalatrophy and clinical manifestations, AD research faces two critical challenges: eliminating the impact of natural aging and extracting valuable clinical data for patients with AD.
UNASSIGNED: This study attempted to address these challenges by developing a novel machine-learning model called tensorized contrastive principal component analysis (T-cPCA). The objectives of this study were to predict AD progression and identify clinical subtypes while minimizing the influence of natural aging.
UNASSIGNED: We leveraged a clinical variable space of 872 features, including almost all AD clinical examinations, which is the most comprehensive AD feature description in current research. T-cPCA yielded the highest accuracy in predicting AD progression by effectively minimizing the confounding effects of natural aging.
UNASSIGNED: The representative features and pathogenic circuits of the four primary AD clinical subtypes were discovered. Confirmed by clinical doctors in Tangdu Hospital, the plaques (18F-AV45) distribution of typical patients in the four clinical subtypes are consistent with representative brain regions found in four AD subtypes, which further offers novel insights into the underlying mechanisms of AD pathogenesis.

This paper examined the mechanical properties of wrist-hand orthoses made from polylactic acid (PLA) and polyethylene terephthalate glycol (PETG), produced through material extrusion with infill densities of 55% and 80%. These orthoses, commonly prescribed for wrist injuries, were 3D-printed flat and subsequently thermoformed to fit the user\'s hand. Experimental and numerical analyses assessed their mechanical resistance to flexion after typical wear conditions, including moisture and long-term aging, as well as their moldability. Digital Imaging Correlation investigations were performed on PLA and PETG specimens for determining the characteristics required for running numerical analysis of the mechanical behavior of the orthoses. The results indicated that even the orthoses with the lower infill density maintained suitable rigidity for wrist immobilization, despite a decrease in their mechanical properties after over one year of shelf life. PLA orthoses with 55% infill density failed at a mean load of 336 N (before aging) and 215 N (after aging), while PETG orthoses did not break during tests. Interestingly, PLA and PETG orthoses with 55% infill density were less influenced by aging compared to their 80% density counterparts. Additionally, moisture and aging affected the PLA orthoses more, with thermoforming, ongoing curing, and stress relaxation as possible explanations related to PETG behavior. Both materials proved viable for daily use, with PETG offering better flexural resistance but posing greater thermoforming challenges.

Tire wear particles (TWP), as an emerging type of microplastics, are a significant source of contaminants in roadside soils due to their high concentration of pollutants, including polycyclic aromatic hydrocarbons (PAHs). This study explored the impact of ultraviolet (UV) exposure and natural aging on the in vitro bioaccessibility of PAHs associated with TWP in soil on a China-wide scale. Our findings suggested that UV exposure amplified the negative charge of TWP by 75 % and increased the hydrophobic groups on the particle surface. The bioaccessibility of 3- and 4-ring PAHs in TWP was significantly (p < 0.05) heightened by UV exposure. After 20 types of soils containing 2 % UV-exposed TWP underwent natural aging, the bioaccessibility of PAHs saw a significant decrease (p < 0.05) to 16-48 %, compared to 28-96 % in the unaged group. Soil pH and electrical conductivity (EC) were the two primary soil properties positively influencing the reduction of in vitro PAHs concentration and PAHs bioaccessibility. According to the prediction results, soils in southern China presented the highest potential region for the release of bioaccessible PAHs from TWP, highlighting the regional specificity of environmental impact. Our study provides valuable insights into the biological impact of PAHs associated with TWP on a regional scale, and offers scientific evidence for targeted soil risk management strategies.

OBJECTIVE: Advanced glycation end-products (AGEs) are implicated in the age-related decline of renal function, exacerbated by conditions, such as hyperglycemia and oxidative stress. The accumulation of AGEs in the kidneys contributes to the progressive decline in renal function observed with aging. However, the precise role and mechanisms of AGEs in the age-related decline of renal function remain unclear. In this study, we investigated the impact and potential mechanisms of AGEs on aging kidneys in naturally aging mice.
METHODS: Male C57BL/6 mice were divided into three groups: 6-, 57-, and 107-week-old. First, the 6- and 107-week-old mice were euthanized. The remaining mice were divided into young (6 weeks) and old (57 weeks) groups. The 57-week-old mice were orally administered aminoguanidine (100 mg/kg/day), an AGEs inhibitor, or vehicle for 13 weeks, resulting in a final age of 70 weeks. The serum and kidney tissues were collected for biochemical measurement, histological examination, immunohistochemistry staining, and immunoblotting analysis.
RESULTS: Our findings revealed a notable accumulation of AGEs in both serum and kidney tissue specimens and renal dysfunction in naturally aging mice. Aminoguanidine not only reversed AGEs accumulation but also ameliorated renal dysfunction. Additionally, aminoguanidine attenuated the upregulation of fibrosis markers (phosphorylated p38/α-SMA and C/EBP homologous protein, CHOP), senescence markers (p53 and p21), and oxidative stress marker (4-HNE) in the aging kidneys.
CONCLUSIONS: These findings underscore the critical role of AGEs in age-related renal dysfunction and highlight the therapeutic potential of aminoguanidine in mitigating fibrosis and senescence, offering prospective avenues for combating age-associated renal ailments.

The natural aging process is accompanied by changes in exosomes, gut microbiota, and metabolites. This study aimed to reveal the anti-aging effect and mechanisms of fecal microbiota transplantation (FMT) from young donors on the natural aging process in mice by analyzing exosomes, gut microbiota, and metabolomics. Aging-relevant telomeric length, oxidative stress indexes in brain tissue, and serum cytokine levels were measured. Flow analysis of T-regulatory (Treg), CD4+, and CD8+ cells was performed, and the expression levels of aging-related proteins were quantified. High-throughput sequencing technology was used to identify differentially expressed serum exosomal miRNAs. Fecal microbiota was tested by 16 S rDNA sequencing. Changes in fecal metabolites were analyzed by UPLC-Q-TOF/MS. The results indicated that the expression of mmu-miR-7010-5p, mmu-miR-376b-5p, mmu-miR-135a-5p, and mmu-miR-3100-5p by serum exosomes was down-regulated and the abundance of opportunistic bacteria (Turicibacter, Allobaculum, Morganella.) was decreased, whereas the levels of protective bacteria (Akkermansia, Muribaculaceae, Helicobacter.) were increased after FMT. Metabolic analysis identified 25 potential biomarkers. Correlation analysis between the gut microbiota and metabolites suggested that the relative abundance of protective bacteria was positively correlated with the levels of spermidine and S-adenosylmethionine. The study indicated that FMT corrected brain injury due to aging via lipid metabolism, the metabolism of cofactors and vitamins, and amino acid metabolism.

Introduction: Aged-related brain damage and gut microbiome disruption are common. Research affirms that modulating the microbiota-gut-brain axis can help reduce age-related brain damage. Methods: Ginseng, esteemed in traditional Chinese medicine, is recognized for its anti-aging capabilities. However, previous Ginseng anti-aging studies have largely focused on diseased animal models. To this end, efforts were hereby made to explore the potential neuroprotective effects of fecal microbiota transplantation (FMT) from Ginseng-supplemented aged mice to those pre-treated with antibiotics. Results: As a result, FMT with specific modifications in natural aging mice improved animal weight gain, extended the telomere length, anti-oxidative stress in brain tissue, regulated the serum levels of cytokine, and balanced the proportion of Treg cells. Besides, FMT increased the abundance of beneficial bacteria of Lachnospiraceae, Dubosiella, Bacteroides, etc. and decreased the levels of potential pathogenic bacteria of Helicobacter and Lachnoclostridium in the fecal samples of natural aged mice. This revealed that FMT remarkably reshaped gut microbiome. Additionally, FMT-treated aged mice showed increased levels of metabolites of Ursolic acid, β-carotene, S-Adenosylmethionine, Spermidine, Guanosine, Celecoxib, Linoleic acid, etc., which were significantly positively correlated with critical beneficial bacteria above. Additionally, these identified critical microbiota and metabolites were mainly enriched in the pathways of Amino acid metabolism, Lipid metabolism, Nucleotide metabolism, etc. Furthermore, FMT downregulated p53/p21/Rb signaling and upregulated p16/p14, ATM/synapsin I/synaptophysin/PSD95, CREB/ERK/AKT signaling in brain damage following natural aging. Discussion: Overall, the study demonstrates that reprogramming of gut microbiota by FMT impedes brain damage in the natural aging process, possibly through the regulation of microbiota-gut-brain axis.

While extensive research has focused on understanding the degradation mechanisms of Poly(vinyl acetate) (PVAC) paint under different environmental conditions, limited attention has been paid to the long-term stability of PVAC-based white glues, especially when used in artworks. This study investigates the accelerated degradation, under simulated photoaging, and isothermal treatment of a commercial PVAC-based white glue considered representative of this class of materials used in contemporary artworks to predict its durability and assess its behavior in art objects. Through accelerated aging experiments and comparison with natural aging observed in artworks, the study reveals the formation of chromophores and the release of plasticizers as key processes; in particular, the progressive darkening was considered an early indicator of degradation processes, before structural changes could be detected by FTIR or NMR spectroscopies. The plasticizer loss induces an increase in glass transition temperature, from 7 °C to temperatures higher than room temperature, affecting the adhesive\'s cohesive strength and contributing to the detachment of materials in artworks. The findings underscore the importance of preventive conservation measures to mitigate degradation issues in PVAC-based artworks.

Due to the natural biochar aging, the improvement of soil quality and immobilization of soil pollutants achieved by biochar may change; understanding the dynamic evolution of the in situ performance of biochar in these roles is essential to discuss the long-term sustainability of biochar remediation. Therefore, in this study, combined biochar from co-pyrolysis of pig manure and invasive Japanese knotweed - P1J1, as well as pure pig manure - PM - and pure Japanese knotweed - JK - derived biochar were applied to investigate their remediation performance in a high As- and Pb-polluted soil with prolonged incubation periods (up to 360 days). Biochar application, especially P1J1 and PM, initially promoted soil pH, dissolved organic carbon, and EC, but the improvements were not constant through time. The JK-treated soil exhibited the highest increase of soil organic matter (OM), followed by P1J1 and then PM, and OM did not change with aging. Biochar, especially P1J1, was a comprehensive nutrient source of Ca, K, Mg, and P to improve soil fertility. However, while soluble cationic Ca, K, and Mg increased with time, anionic P decreased over time, indicating that continuous P availability might not be guaranteed with the aging process. The total microorganism content declined with time; adding biochars slowed down this tendency, which was more remarkable at the later incubation stage. Biochar significantly impeded soil Pb mobility but mobilized soil As, especially in PM- and P1J1-treated soils. However, mobilized As gradually re-fixed in the long run; meanwhile, the excellent Pb immobilization achieved by biochars was slightly reduced with time. The findings of this study offer fresh insights into the alterations in metal(loid)s mobility over an extended duration, suggesting that the potential mobilization risk of As is reduced while Pb mobility slightly increases over time.

A significant distinction between cigar production and tobacco lies in the necessary aging process, where intricate microbial growth, metabolic activities, enzymatic catalysis, and chemical reactions interact. Despite its crucial role in determining the final quality of cigars, our comprehension of the underlying chemical and biological mechanisms within this process remains insufficient. Biomass and alkaloids are the primary constituents that influence the flavor of cigars. Consequently, investigating the entire aging process could begin by exploring the involvement of microbes and enzymes in their biodegradation. In this study, handmade cigars were aged under different conditions. Metagenomic sequencing was employed to identify the microbes and enzymes responsible for the degradation of biomass and alkaloids derived from tobacco leaves. The results revealed that various environmental factors, including temperature, humidity, duration time, and turning frequency, yielded varying contents of total sugar and alkaloids in the cigars. Significant correlations were observed between microbial communities and starch, reducing sugars, total sugars, and alkaloids. Key species involved in the breakdown of biomass constituents, such as starch (Bacillus pumilus, Pseudomonas sp. 286, and Aspergillus cristatus), reducing sugars and total sugars (Aspergillus cristatus and Nitrolancea hollandica), were identified. Furthermore, Corynespora cassiicola and Pseudomonas fulva were found to potentially contribute to the degradation of alkaloid compounds, specifically nornicotine and neonicotinoid. Our work contributes to a deeper understanding of the microbial roles in the aging of cigars. Moreover, the selection of specific microbial strains or starter cultures can be employed to control and manipulate the aging process, thereby further refining the flavor development in cigar products.

This review discusses the relationship between cellular senescence and radiation exposure. Given the wide range of ionizing radiation sources encountered by people in professional and medical spheres, as well as the influence of natural background radiation, the question of the effect of radiation on biological processes, particularly on aging processes, remains highly relevant. The parallel relationship between natural and radiation-induced cellular senescence reveals the common aspects underlying these processes. Based on recent scientific data, the key points of the effects of ionizing radiation on cellular processes associated with aging, such as genome instability, mitochondrial dysfunction, altered expression of miRNAs, epigenetic profile, and manifestation of the senescence-associated secretory phenotype (SASP), are discussed. Unraveling the molecular mechanisms of cellular senescence can make a valuable contribution to the understanding of the molecular genetic basis of age-associated diseases in the context of environmental exposure.