Effects of disc overhang diameter on the uplift bearing capacity of new-type concrete expanded-plate pile groups.

The disc overhang diameter can significantly affect the uplift bearing capacity of new concrete expanded-plate pile groups, affecting their design and practical applications. Accordingly, this effect was investigated considering the failure laws of the soil surrounding various pile types and groups. Based on the uplift bearing capacities of single and double piles, a finite element simulation was adopted to establish models for the four-, six-, and nine-pile groups. The relationship between the disc overhang diameter and uplift-bearing capacity of each pile group was explored: as the disk overhang diameter increased, the uplift-bearing capacities of the pile groups increased; however, this relationship is nonlinear. The optimal disc overhang diameter was determined as 1.5-1.75 times the pile diameter. For a constant disc overhang diameter, corner piles have a greater uplift bearing capacity than side piles in the six-pile group, and a greater uplift bearing capacity than the side and center piles in the nine-pile group. Thus, the pile-group effect depends on the pile position. The uplift bearing capacity did not increase linearly with the number of piles, and the average uplift bearing capacity of a pile in a pile group was less than that of a single pile. Therefore, the uplift bearing capacity of the pile groups decreased as the number of piles increased. The reliability of the simulation was verified via visual testing of a small-scale half-cut pile model.

The sirtuin-associated human senescence program converges on the activation of placenta-specific gene PAPPA.

Sirtuins are pro-longevity genes with chromatin modulation potential, but how these properties are connected is not well understood. Here, we generated a panel of isogeneic human stem cell lines with SIRT1-SIRT7 knockouts and found that any sirtuin deficiency leads to accelerated cellular senescence. Through large-scale epigenomic analyses, we show how sirtuin deficiency alters genome organization and that genomic regions sensitive to sirtuin deficiency are preferentially enriched in active enhancers, thereby promoting interactions within topologically associated domains and the formation of de novo enhancer-promoter loops. In all sirtuin-deficient human stem cell lines, we found that chromatin contacts are rewired to promote aberrant activation of the placenta-specific gene PAPPA, which controls the pro-senescence effects associated with sirtuin deficiency and serves as a potential aging biomarker. Based on our survey of the 3D chromatin architecture, we established connections between sirtuins and potential target genes, thereby informing the development of strategies for aging interventions.

SGF29 nuclear condensates reinforce cellular aging.

Phase separation, a biophysical segregation of subcellular milieus referred as condensates, is known to regulate transcription, but its impacts on physiological processes are less clear. Here, we demonstrate the formation of liquid-like nuclear condensates by SGF29, a component of the SAGA transcriptional coactivator complex, during cellular senescence in human mesenchymal progenitor cells (hMPCs) and fibroblasts. The Arg 207 within the intrinsically disordered region is identified as the key amino acid residue for SGF29 to form phase separation. Through epigenomic and transcriptomic analysis, our data indicated that both condensate formation and H3K4me3 binding of SGF29 are essential for establishing its precise chromatin location, recruiting transcriptional factors and co-activators to target specific genomic loci, and initiating the expression of genes associated with senescence, such as CDKN1A. The formation of SGF29 condensates alone, however, may not be sufficient to drive H3K4me3 binding or achieve transactivation functions. Our study establishes a link between phase separation and aging regulation, highlighting nuclear condensates as a functional unit that facilitate shaping transcriptional landscapes in aging.

SIRT2 counteracts primate cardiac aging via deacetylation of STAT3 that silences CDKN2B.

Aging is a major risk factor contributing to pathophysiological changes in the heart, yet its intrinsic mechanisms have been largely unexplored in primates. In this study, we investigated the hypertrophic and senescence phenotypes in the hearts of aged cynomolgus monkeys as well as the transcriptomic and proteomic landscapes of young and aged primate hearts. SIRT2 was identified as a key protein decreased in aged monkey hearts, and engineered SIRT2 deficiency in human pluripotent stem cell-derived cardiomyocytes recapitulated key senescence features of primate heart aging. Further investigations revealed that loss of SIRT2 in human cardiomyocytes led to the hyperacetylation of STAT3, which transcriptionally activated CDKN2B and, in turn, triggered cardiomyocyte degeneration. Intra-myocardial injection of lentiviruses expressing SIRT2 ameliorated age-related cardiac dysfunction in mice. Taken together, our study provides valuable resources for decoding primate cardiac aging and identifies the SIRT2-STAT3-CDKN2B regulatory axis as a potential therapeutic target against human cardiac aging and aging-related cardiovascular diseases.

Genome-wide CRISPR activation screening in senescent cells reveals SOX5 as a driver and therapeutic target of rejuvenation.

Our understanding of the molecular basis for cellular senescence remains incomplete, limiting the development of strategies to ameliorate age-related pathologies by preventing stem cell senescence. Here, we performed a genome-wide CRISPR activation (CRISPRa) screening using a human mesenchymal precursor cell (hMPC) model of the progeroid syndrome. We evaluated targets whose activation antagonizes cellular senescence, among which SOX5 outperformed as a top hit. Through decoding the epigenomic landscapes remodeled by overexpressing SOX5, we uncovered its role in resetting the transcription network for geroprotective genes, including HMGB2. Mechanistically, SOX5 binding elevated the enhancer activity of HMGB2 with increased levels of H3K27ac and H3K4me1, raising HMGB2 expression so as to promote rejuvenation. Furthermore, gene therapy with lentiviruses carrying SOX5 or HMGB2 rejuvenated cartilage and alleviated osteoarthritis in aged mice. Our study generated a comprehensive list of rejuvenators, pinpointing SOX5 as a potent driver for rejuvenation both in vitro and in vivo.

Nuclear lamina erosion-induced resurrection of endogenous retroviruses underlies neuronal aging.

The primate frontal lobe (FL) is sensitive to aging-related neurocognitive decline. However, the aging-associated molecular mechanisms remain unclear. Here, using physiologically aged non-human primates (NHPs), we depicted a comprehensive landscape of FL aging with multidimensional profiling encompassing bulk and single-nucleus transcriptomes, quantitative proteome, and DNA methylome. Conjoint analysis across these molecular and neuropathological layers underscores nuclear lamina and heterochromatin erosion, resurrection of endogenous retroviruses (ERVs), activated pro-inflammatory cyclic GMP-AMP synthase (cGAS) signaling, and cellular senescence in post-mitotic neurons of aged NHP and human FL. Using human embryonic stem-cell-derived neurons recapitulating cellular aging in vitro, we verified the loss of B-type lamins inducing resurrection of ERVs as an initiating event of the aging-bound cascade in post-mitotic neurons. Of significance, these aging-related cellular and molecular changes can be alleviated by abacavir, a nucleoside reverse transcriptase inhibitor, either through direct treatment of senescent human neurons in vitro or oral administration to aged mice.

Adult upper-limb forearm lymphoma hygroma (cystic lymphangioma): A case report.

INTRODUCTION: Lymphoma hygroma (LH) that is the most common type of lymphangioma, but it rarely occurs in the forearm. It may show localized invasive behavior, but is benign. CASE PRESENTATION: A 42-year-old woman presented to our hospital with a growing strip-like mass in the right forearm that had been detected 3 years earlier. Ultrasound examination showed a subcutaneous strip of low back vocal cords on the right forearm. Further magnetic resonance imaging (MRI) showed irregular strip-like dilated lymphatic vessels characteristic of LH with low T1 signal intensity and high T2 signal intensity. After radical surgical resection, hematoxylin-eosin (H & E) and immunohistochemical (IHC) staining of cystic LH endothelial cells labeled with monoclonal antibody D2-40 showed a dilated lymphangioma with no evidence of malignancy. After 7 months of follow-up, no tumor recurrence was seen and the effect was satisfactory. CLINICAL DISCUSSION: A combination of previous trauma history, signs and symptoms, and imaging evaluation are necessary to provide clues to LH, but the final diagnosis is likely to be made by pathologic evaluation of the resected specimen. Although there are many treatment modalities, all also have different outcomes. The absence of complete resection resulting in a tumor remnant is the foremost cause of LH recurrence, so we believe that the preferred approach against LH remains complete surgical resection. CONCLUSIONS: LH is benign and generally asymptomatic lesions with mild bio-behavior. As there are occasional confusing presentations, similar cystic lesions should still be considered with caution for the disease. Although MRI provides superior advantages for its diagnosis, the confirmation of diagnosis still requires histological examination. Radical lesion resection is a very safe and effective option for the treatment of LH.

Single-nucleus transcriptomics reveals a gatekeeper role for FOXP1 in primate cardiac aging.

Aging poses a major risk factor for cardiovascular diseases, the leading cause of death in the aged population. However, the cell type-specific changes underlying cardiac aging are far from being clear. Here, we performed single-nucleus RNA-sequencing analysis of left ventricles from young and aged cynomolgus monkeys to define cell composition changes and transcriptomic alterations across different cell types associated with age. We found that aged cardiomyocytes underwent a dramatic loss in cell numbers and profound fluctuations in transcriptional profiles. Via transcription regulatory network analysis, we identified FOXP1, a core transcription factor in organ development, as a key downregulated factor in aged cardiomyocytes, concomitant with the dysregulation of FOXP1 target genes associated with heart function and cardiac diseases. Consistently, the deficiency of FOXP1 led to hypertrophic and senescent phenotypes in human embryonic stem cell-derived cardiomyocytes. Altogether, our findings depict the cellular and molecular landscape of ventricular aging at the single-cell resolution, and identify drivers for primate cardiac aging and potential targets for intervention against cardiac aging and associated diseases.

m6A epitranscriptomic regulation of tissue homeostasis during primate aging.

How N6-methyladenosine (m6A), the most abundant mRNA modification, contributes to primate tissue homeostasis and physiological aging remains elusive. Here, we characterize the m6A epitranscriptome across the liver, heart and skeletal muscle in young and old nonhuman primates. Our data reveal a positive correlation between m6A modifications and gene expression homeostasis across tissues as well as tissue-type-specific aging-associated m6A dynamics. Among these tissues, skeletal muscle is the most susceptible to m6A loss in aging and shows a reduction in the m6A methyltransferase METTL3. We further show that METTL3 deficiency in human pluripotent stem cell-derived myotubes leads to senescence and apoptosis, and identify NPNT as a key element downstream of METTL3 involved in myotube homeostasis, whose expression and m6A levels are both decreased in senescent myotubes. Our study provides a resource for elucidating m6A-mediated mechanisms of tissue aging and reveals a METTL3-m6A-NPNT axis counteracting aging-associated skeletal muscle degeneration.

Resurrection of endogenous retroviruses during aging reinforces senescence.

Whether and how certain transposable elements with viral origins, such as endogenous retroviruses (ERVs) dormant in our genomes, can become awakened and contribute to the aging process is largely unknown. In human senescent cells, we found that HERVK (HML-2), the most recently integrated human ERVs, are unlocked to transcribe viral genes and produce retrovirus-like particles (RVLPs). These HERVK RVLPs constitute a transmissible message to elicit senescence phenotypes in young cells, which can be blocked by neutralizing antibodies. The activation of ERVs was also observed in organs of aged primates and mice as well as in human tissues and serum from the elderly. Their repression alleviates cellular senescence and tissue degeneration and, to some extent, organismal aging. These findings indicate that the resurrection of ERVs is a hallmark and driving force of cellular senescence and tissue aging.

A Review of Strategies Associated with Surgical Decompression in Traumatic Spinal Cord Injury.

Traumatic spinal cord injury (TSCI) is frequent. Timely diagnosis and treatment have reduced the mortality, but the long-term recovery of neurologic functions remains ominous. After TSCI, tissue bleeding, edema, and adhesions lead to an increase in the intraspinal pressure, further causing the pathophysiologic processes of ischemia and hypoxia and eventually accelerating the cascade of secondary spinal cord injury. Timely surgery with appropriate decompression strategies can reduce that secondary injury. However, disagreement about the safety and effectiveness of decompression surgery and the timing of surgery still exists. The level and severity of spinal cord injury do have an impact on the timing of surgery; therefore, TSCI subpopulations may benefit from early surgery. Early surgery perhaps has little effect on recovery from complete TSCI but might be of benefit in patients with incomplete injury. Early decompression should be considered in patients with incomplete cervical TSCI. Patient age should not be used as an exclusion criterion for early surgery. The best time point for early surgery is although influenced by the shortest duration to thoroughly examine the patient's condition and stabilize the patient's state. After the patient's condition is fully evaluated, we can perform the surgical modality of emergency myelotomy and decompression. Therefore, a number of conditions should be considered, such as standardized decompression methods, indications and operation timing to ensure the effectiveness and safety of early surgical intervention, and promotion of the functional recovery of residual nerve tissue.

Renovation as innovation: Repurposing human antibacterial peptide LL-37 for cancer therapy.

In many organisms, antimicrobial peptides (AMPs) display wide activities in innate host defense against microbial pathogens. Mammalian AMPs include the cathelicidin and defensin families. LL37 is the only one member of the cathelicidin family of host defense peptides expressed in humans. Since its discovery, it has become clear that they have pleiotropic effects. In addition to its antibacterial properties, many studies have shown that LL37 is also involved in a wide variety of biological activities, including tissue repair, inflammatory responses, hemotaxis, and chemokine induction. Moreover, recent studies suggest that LL37 exhibits the intricate and contradictory effects in promoting or inhibiting tumor growth. Indeed, an increasing amount of evidence suggests that human LL37 including its fragments and analogs shows anticancer effects on many kinds of cancer cell lines, although LL37 is also involved in cancer progression. Focusing on recent information, in this review, we explore and summarize how LL37 contributes to anticancer effect as well as discuss the strategies to enhance delivery of this peptide and selectivity for cancer cells.

TA-MSCs, TA-MSCs-EVs, MIF: their crosstalk in immunosuppressive tumor microenvironment.

As an important component of the immunosuppressive tumor microenvironment (TME), it has been established that mesenchymal stem cells (MSCs) promote the progression of tumor cells. MSCs can directly promote the proliferation, migration, and invasion of tumor cells via cytokines and chemokines, as well as promote tumor progression by regulating the functions of anti-tumor immune and immunosuppressive cells. MSCs-derived extracellular vesicles (MSCs-EVs) contain part of the plasma membrane and signaling factors from MSCs; therefore, they display similar effects on tumors in the immunosuppressive TME. The tumor-promoting role of macrophage migration inhibitory factor (MIF) in the immunosuppressive TME has also been revealed. Interestingly, MIF exerts similar effects to those of MSCs in the immunosuppressive TME. In this review, we summarized the main effects and related mechanisms of tumor-associated MSCs (TA-MSCs), TA-MSCs-EVs, and MIF on tumors, and described their relationships. On this basis, we hypothesized that TA-MSCs-EVs, the MIF axis, and TA-MSCs form a positive feedback loop with tumor cells, influencing the occurrence and development of tumors. The functions of these three factors in the TME may undergo dynamic changes with tumor growth and continuously affect tumor development. This provides a new idea for the targeted treatment of tumors with EVs carrying MIF inhibitors.

Large-scale chromatin reorganization reactivates placenta-specific genes that drive cellular aging.

Nuclear deformation, a hallmark frequently observed in senescent cells, is presumed to be associated with the erosion of chromatin organization at the nuclear periphery. However, how such gradual changes in higher-order genome organization impinge on local epigenetic modifications to drive cellular mechanisms of aging has remained enigmatic. Here, through large-scale epigenomic analyses of isogenic young, senescent, and progeroid human mesenchymal progenitor cells (hMPCs), we delineate a hierarchy of integrated structural state changes that manifest as heterochromatin loss in repressive compartments, euchromatin weakening in active compartments, switching in interfacing topological compartments, and increasing epigenetic entropy. We found that the epigenetic de-repression unlocks the expression of pregnancy-specific beta-1 glycoprotein (PSG) genes that exacerbate hMPC aging and serve as potential aging biomarkers. Our analyses provide a rich resource for uncovering the principles of epigenomic landscape organization and its changes in cellular aging and for identifying aging drivers and intervention targets with a genome-topology-based mechanism.

(-)-Epigallocatechin Gallate Attenuates Spinal Motoneuron Death Induced by Brachial Plexus Root Avulsion in Rats.

BACKGROUND: Recent studies have indicated that epigallocatechin gallate (EGCG) benefits a variety of neurological insults. This study was performed to investigate the neuroprotective effect of EGCG after brachial plexus root avulsion in SD rats. METHODS: One hundred twenty SD rats were randomized into the following three groups: an EGCG group, an Avulsion group, and a Sham group. There were 40 rats in each group. EGCG (100 mg/kg, i.p.) or normal saline was administered to rats immediately following the injuries. The treatment was continued from day 1 to day 7, and the animals were sacrificed on days 3, 7, 14, and 28 post-surgery for the harvesting of spinal cord samples for Nissl staining, immunohistochemistry (caspase-3, p-JNK, p-c-Jun), and western blot analysis (p-JNK, JNK, p-c-Jun, c-Jun). RESULTS: EGCG treatment caused significant increases in the percentage of surviving motoneurons on days 14 and 28 (p<0.05) compared to the control animals. On days 3 and 7 after avulsion, the numbers of caspase-3-positive motoneurons in the EGCG-treated animals were significantly fewer than in the control animals (p<0.05). The numbers of p- JNK-positive motoneurons and the ratio of p-JNK/JNK were no significant differences between the Avulsion group and the EGCG-treated group after injury at any time point. The numbers of p-c-Jun-positive motoneurons and the ratio of p-c-Jun/c-Jun were significantly lower in the EGCG-treated group compared with the Avulsion group at 3d and 7d after injury (p<0.05). CONCLUSION: Our results indicated that motoneurons were protected by EGCG against the cell death induced by brachial plexus root avulsion, and this effect was correlated with inhibiting c-Jun phosphorylation.

BMAL1 moonlighting as a gatekeeper for LINE1 repression and cellular senescence in primates.

Aging in humans is intricately linked with alterations in circadian rhythms concomitant with physiological decline and stem cell exhaustion. However, whether the circadian machinery directly regulates stem cell aging, especially in primates, remains poorly understood. In this study, we found that deficiency of BMAL1, the only non-redundant circadian clock component, results in an accelerated aging phenotype in both human and cynomolgus monkey mesenchymal progenitor cells (MPCs). Unexpectedly, this phenotype was mainly attributed to a transcription-independent role of BMAL1 in stabilizing heterochromatin and thus preventing activation of the LINE1-cGAS-STING pathway. In senescent primate MPCs, we observed decreased capacity of BMAL1 to bind to LINE1 and synergistic activation of LINE1 expression. Likewise, in the skin and muscle tissues from the BMAL1-deficient cynomolgus monkey, we observed destabilized heterochromatin and aberrant LINE1 transcription. Altogether, these findings uncovered a noncanonical role of BMAL1 in stabilizing heterochromatin to inactivate LINE1 that drives aging in primate cells.

Cross-species metabolomic analysis identifies uridine as a potent regeneration promoting factor.

Regenerative capacity declines throughout evolution and with age. In this study, we asked whether metabolic programs underlying regenerative capability might be conserved across species, and if so, whether such metabolic drivers might be harnessed to promote tissue repair. To this end, we conducted metabolomic analyses in two vertebrate organ regeneration models: the axolotl limb blastema and antler stem cells. To further reveal why young individuals have higher regenerative capacity than the elderly, we also constructed metabolic profiles for primate juvenile and aged tissues, as well as young and aged human stem cells. In joint analyses, we uncovered that active pyrimidine metabolism and fatty acid metabolism correlated with higher regenerative capacity. Furthermore, we identified a set of regeneration-related metabolite effectors conserved across species. One such metabolite is uridine, a pyrimidine nucleoside, which can rejuvenate aged human stem cells and promote regeneration of various tissues in vivo. These observations will open new avenues for metabolic intervention in tissue repair and regeneration.