Subgrading of G2 Pancreatic Neuroendocrine Tumors as 2A (Ki67 3% to < 10%) Versus 2B (10% to ≤ 20%) Identifies Behaviorally Distinct Subsets in Keeping with the Evolving Management Protocols.

BACKGROUND: Grade 1/2 PanNETs are mostly managed similarly, typically without any adjunct treatment with the belief that their overall metastasis rate is low. In oncology literature, Ki67-index of 10% is increasingly being used as the cutoff in stratifying patients to different protocols, although there are no systematic pathology-based studies supporting this approach. METHODS: Ki67-index was correlated with clinicopathologic parameters in 190 resected PanNETs. A validation cohort (n = 145) was separately analyzed. RESULTS: In initial cohort, maximally selected rank statistics method revealed 12% to be the discriminatory cutoff (close to 10% rule of thumb). G2b cases had liver/distant metastasis rate of almost threefold higher than that of G2a and showed significantly higher frequency of all histopathologic signs of aggressiveness (tumor size, perineural/vascular invasion, infiltrative growth pattern, lymph node metastasis). In validation cohort, these figures were as striking. When all cases were analyzed together, compared with G1, the G2b category had nine times higher liver/distant metastasis rate (6.1 vs. 58.5%; p < 0.001) and three times higher lymph node metastasis rate (20.5 vs. 65.1%; p < 0.001). CONCLUSIONS: G2b PanNETs act very similar to G3, supporting management protocols that regard them as potential therapy candidates. Concerning local management, metastatic behavior in G2b cases indicate they may not be as amenable for conservative approaches, such as watchful waiting or enucleation. This substaging should be considered into diagnostic guidelines, and clinical trials need to be devised to determine the more appropriate management protocols for G2b (10% to ≤ 20%) group, which shows liver/distant metastasis in more than half of the cases, which at minimum warrants closer follow-up.

Training immunophenotyping deep learning models with the same-section ground truth cell label derivation method improves virtual staining accuracy.

Introduction: Deep learning (DL) models predicting biomarker expression in images of hematoxylin and eosin (H&E)-stained tissues can improve access to multi-marker immunophenotyping, crucial for therapeutic monitoring, biomarker discovery, and personalized treatment development. Conventionally, these models are trained on ground truth cell labels derived from IHC-stained tissue sections adjacent to H&E-stained ones, which might be less accurate than labels from the same section. Although many such DL models have been developed, the impact of ground truth cell label derivation methods on their performance has not been studied. Methodology: In this study, we assess the impact of cell label derivation on H&E model performance, with CD3+ T-cells in lung cancer tissues as a proof-of-concept. We compare two Pix2Pix generative adversarial network (P2P-GAN)-based virtual staining models: one trained with cell labels obtained from the same tissue section as the H&E-stained section (the 'same-section' model) and one trained on cell labels from an adjacent tissue section (the 'serial-section' model). Results: We show that the same-section model exhibited significantly improved prediction performance compared to the 'serial-section' model. Furthermore, the same-section model outperformed the serial-section model in stratifying lung cancer patients within a public lung cancer cohort based on survival outcomes, demonstrating its potential clinical utility. Discussion: Collectively, our findings suggest that employing ground truth cell labels obtained through the same-section approach boosts immunophenotyping DL solutions.

Small Bowel Pyloric Metaplasia is Associated with Lower Rates of Earlier Recurrence of Crohn's Disease after Resection.

Recurrence within one or two years is common after Crohn's disease (CD) resection. In this study, we seek to identify histologic features in CD resections that may predict earlier (≤18 months) recurrence to potentially guide post-operative management. A single-institution, retrospective review was performed on patients with first-time CD bowel resection specimens (2002-2007). Patient demographics and CD course were also documented. Slides were reviewed for inflammatory distribution and composition, small bowel (SB) pyloric metaplasia (PM), and presence and characteristics of submucosal fibrosis and granulomas. In our cohort, 14 of 41 patients experienced earlier clinical or endoscopic recurrence after initial resection. In the 38 patients who underwent SB resection (3 were colon only), PM was less common in those with earlier recurrence (6/12 [50%]) compared to those with later (>18 months) or no known recurrence (22/26 [85%]) (P=0.045). PM was present even in patients with < 1 year of known CD. Additionally, therapy with anti-tumor necrosis factor (TNF) prior to surgery was more common in earlier recurrence patients (7/14 [50%]) than later or no recurrence patients (4/27 [15%]) (P = 0.026). There was no significant difference in age, sex, smoking status, duration of CD, post-operative CD medication, distribution or features of inflammation, granulomas, or fibrosis. Overall, our results indicate that SB PM and pre-surgical anti-TNF therapy are possible helpful clinicopathologic features to evaluate for recurrence risk.

Total sputum nitrate/nitrite is associated with exacerbations and Pseudomonas aeruginosa colonisation in bronchiectasis.

Background: Sputum nitrate/nitrite, which is the main component of reactive nitrogen species, is a potential biomarker of disease severity and progression in bronchiectasis. This study aimed to determine the association between nitrate/nitrite and exacerbations and airway microbiota in bronchiectasis. Methods: We measured total nitrate/nitrite concentration in sputum samples collected from 85 patients with stable bronchiectasis, performed 16S ribosomal RNA sequencing of sputum samples and predicted the denitrification ability of airway microbiota using Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt). Relationships between sputum total nitrate/nitrite and disease severity, exacerbations and airway microbiota were examined. Results: Higher total sputum nitrate/nitrite was associated with more severe bronchiectasis defined by E-FACED (exacerbation, forced expiratory volume in 1 s, age, chronic colonisation by Pseudomonas aeruginosa, radiological extension and dyspnoea) (p=0.003) or Bronchiectasis Severity Index (p=0.006) and more exacerbations in the prior 12 months (p=0.005). Moreover, total sputum nitrate/nitrite was significantly higher in patients with worse cough score (p=0.03), worse sputum purulence score (p=0.01) and worse Medical Research Council dyspnoea score (p=0.02). In addition, the total sputum nitrate/nitrite of the P. aeruginosa colonised (PA) group was higher than that of the non-P. aeruginosa colonised (NPA) group (p=0.04), and the relative abundance of P. aeruginosa was positively correlated with total nitrate/nitrite (r=0.337, p=0.002). Denitrification module (M00529) was also significantly enriched in the PA group compared to the NPA group through PICRUSt analyses. Using receiver-operating characteristic analysis, total nitrate/nitrite was associated with exacerbations during 1-year follow-up (area under the curve 0.741, p=0.014). Conclusions: Sputum nitrate/nitrite is a biomarker of disease severity and associated with P. aeruginosa colonisation in bronchiectasis.

Clinicopathologic Features of Gastrointestinal Tract Langerhans Cell Histiocytosis.

Gastrointestinal (GI) tract involvement by Langerhans cell histiocytosis (LCH) is rare and its clinicopathologic characteristics have only been described in case reports and small series. We reviewed hematoxylin and eosin and CD1a, S100, and Langerin immunohistochemical-stained slides from 47 patients with well-documented demographic and clinical findings. Our cases included 8 children and 39 adults, with a mean follow-up of 63 months. All pediatric patients had concurrent multisystem LCH, presented with GI symptoms, and showed nonpolypoid lesions. Seven (88%) showed multifocal GI disease, including 5 with multiple GI organ involvement. All sampled lesions from children exhibited infiltrative growth. More than half had died of the disease or manifested persistent LCH at last follow-up. Twenty-five of 39 (64%) adults had LCH involving only the GI tract (single system), with the remaining 14 (36%) exhibiting multisystem disease. Adult single-system GI LCH was typically encountered incidentally on screening/surveillance endoscopy (72%). Most exhibited isolated colorectal involvement (88%) as a solitary polyp (92%), with a well-demarcated/noninfiltrative growth pattern (70%), and excellent prognosis (100%). In comparison, adult patients with multisystem LCH more frequently presented with GI symptoms (92%, P < .001), noncolorectal GI site involvement (50%, P = .02), multifocal GI lesions (43%, P = .005), nonpolypoid lesions (71%, P < .001), infiltrative histologic growth pattern (78%, P = .04), and persistent disease (57%, P < .001). Adult patients with multisystem LCH appear to exhibit similar clinicopathologic features to those of pediatric patients. These results demonstrated that adults with single-system LCH involving the GI tract have an excellent prognosis, whereas multisystem LCH occurring at any age carries an unfavorable prognosis. High-risk features of GI LCH include pediatric age, GI symptomatology, noncolorectal GI involvement, multifocal GI disease, nonpolypoid lesions, and infiltrative growth pattern.

Insight into the bacterial community composition of the plastisphere in diverse environments of a coastal salt marsh.

The microbial community colonized on microplastics (MPs), known as the 'plastisphere', has attracted extensive concern owing to its environmental implications. Coastal salt marshes, which are crucial ecological assets, are considered sinks for MPs. Despite their strong spatial heterogeneity, there is limited information on plastisphere across diverse environments in coastal salt marshes. Herein, a 1-year field experiment was conducted at three sites in the Yancheng salt marsh in China. This included two sites in the intertidal zone, bare flat (BF) and Spartina alterniflora vegetation area (SA), and one site in the supratidal zone, Phragmites australis vegetation area (PA). Petroleum-based MPs (polyethylene and expanded polystyrene) and bio-based MPs (polylactic acid and polybutylene succinate) were employed. The results revealed significant differences in bacterial community composition between the plastisphere and sediment at all three sites examined, and the species enriched in the plastisphere exhibited location-specific characteristics. Overall, the largest difference was observed at the SA site, whereas the smallest difference was observed at the BF site. Furthermore, the MP polymer types influenced the composition of the bacterial communities in the plastisphere, also exhibiting location-specific characteristics, with the most pronounced impact observed at the PA site and the least at the BF site. The polybutylene succinate plastisphere bacterial communities at the SA and PA sites were quite different from the plastispheres from the other three MP polymer types. Co-occurrence network analyses suggested that the bacterial community network in the BF plastisphere exhibited the highest complexity, whereas the network in the SA plastisphere showed relatively sparse interactions. Null model analyses underscored the predominant role of deterministic processes in shaping the assembly of plastisphere bacterial communities across all three sites, with a more pronounced influence observed in the intertidal zone than in the supratidal zone. This study enriches our understanding of the plastisphere in coastal salt marshes.

Dual-Mechanism Peptide SR25 has Broad Antimicrobial Activity and Potential Application for Healing Bacteria-infected Diabetic Wounds.

The rise of antibiotic resistance poses a significant public health crisis, particularly due to limited antimicrobial options for the treatment of infections with Gram-negative pathogens. Here, an antimicrobial peptide (AMP) SR25 is characterized, which effectively kills both Gram-negative and Gram-positive bacteria through a unique dual-targeting mechanism without detectable resistance. Meanwhile, an SR25-functionalized hydrogel is developed for the efficient treatment of infected diabetic wounds. SR25 is obtained through genome mining from an uncultured bovine enteric actinomycete named Nonomuraea Jilinensis sp. nov. Investigations reveal that SR25 has two independent cellular targets, disrupting bacterial membrane integrity and restraining the activity of succinate:quinone oxidoreductase (SQR). In a diabetic mice wound infection model, the SR25-incorporated hydrogel exhibits high efficacy against mixed infections of Escherichia coli (E. coli) and methicillin-resistant Staphylococcus aureus (MRSA), accelerating wound healing. Overall, these findings demonstrate the therapeutic potential of SR25 and highlight the value of mining drugs with multiple mechanisms from uncultured animal commensals for combating challenging bacterial pathogens.

Activation of nicotinic acetylcholine receptor α7 subunit limits Zika viral infection via promoting autophagy and ferroptosis.

Vagus nerve regulates viral infection and inflammation via the alpha 7 nicotinic acetylcholine receptor (α7 nAChR); however, the role of α7 nAChR in ZIKA virus (ZIKV) infection, which can cause severe neurological diseases such as microcephaly and Guillain-Barré syndrome, remains unknown. Here, we first examined the role of α7 nAChR in ZIKV infection in vitro. A broad effect of α7 nAChR activation was identified in limiting ZIKV infection in multiple cell lines. Combined with transcriptomics analysis, we further demonstrated that α7 nAChR activation promoted autophagy and ferroptosis pathways to limit cellular ZIKV viral loads. Additionally, activation of α7 nAChR prevented ZIKV-induced p62 nucleus accumulation, which mediated an enhanced autophagy pathway. By regulating proteasome complex and an E3 ligase NEDD4, activation of α7 nAChR resulted in increased amount of cellular p62, which further enhanced the ferroptosis pathway to reduce ZIKV infection. Moreover, utilizing in vivo neonatal mouse models, we showed that α7 nAChR is essential in controlling the disease severity of ZIKV infection. Taken together, our findings identify an α7 nAChR-mediated effect that critically contributes to limiting ZIKV infection, and α7 nAChR activation offers a novel strategy for combating ZIKV infection and its complications.

A lactate-SREBP2 signaling axis drives tolerogenic dendritic cell maturation and promotes cancer progression.

Conventional dendritic cells (DCs) are essential mediators of antitumor immunity. As a result, cancers have developed poorly understood mechanisms to render DCs dysfunctional within the tumor microenvironment (TME). After identification of CD63 as a specific surface marker, we demonstrate that mature regulatory DCs (mregDCs) migrate to tumor-draining lymph node tissues and suppress DC antigen cross-presentation in trans while promoting T helper 2 and regulatory T cell differentiation. Transcriptional and metabolic studies showed that mregDC functionality is dependent on the mevalonate biosynthetic pathway and its master transcription factor, SREBP2. We found that melanoma-derived lactate activates SREBP2 in tumor DCs and drives conventional DC transformation into mregDCs via homeostatic or tolerogenic maturation. DC-specific genetic silencing and pharmacologic inhibition of SREBP2 promoted antitumor CD8+ T cell activation and suppressed melanoma progression. CD63+ mregDCs were found to reside within the lymph nodes of several preclinical tumor models and in the sentinel lymph nodes of patients with melanoma. Collectively, this work suggests that a tumor lactate-stimulated SREBP2-dependent program promotes CD63+ mregDC development and function while serving as a promising therapeutic target for overcoming immune tolerance in the TME.

Histologic Features of Mycobacterial Spindle Cell Pseudotumors: A Multi-institutional Clinicopathologic Analysis of 14 Cases.

Mycobacterial spindle cell pseudotumors (MSPs) are a rare and diagnostically challenging manifestation of non-tuberculous mycobacterial (NTM) infections. Proper recognition of these pseudotumors is important because they are treatable and benign. In this study, we evaluated the morphologic patterns of MSPs to improve their pathologic identification. Clinical and morphologic features of 14 MSPs were analyzed. Histologic factors evaluated included the architectural growth pattern of spindled or epithelioid macrophages, granulomas and their location within the lesion, neutrophilic microabscesses, multinucleated giant cells, necrosis, and effacement of background tissue. The composition of inflammatory infiltrates, organism density by acid-fast staining, and stromal changes were also assessed. In addition, 8 of 14 cases underwent molecular microbiology identification by a clinical amplicon-sequencing assay for non-tuberculous mycobacteria. MSP sites included 2 bowel, 10 lymph nodes, 1 liver, and 1 extremity. Cases with available clinical history (n=10) all occurred in immunocompromised patients. All demonstrated effacement of normal structures with spindled cells arranged in a storiform or fascicular architectural pattern. In addition, all cases showed lymphocytic inflammation, with prominent concurrent neutrophilic inflammation in 50% (7/14) of cases. Other morphologic findings included foamy histiocytes (64%, 9/14), peripherally situated granulomas (21%, 3/14), and neutrophilic microabscesses (21%, 3/14). All tested cases were positive for NTM by PCR methods. Mycobacterium avium was the most commonly isolated pathogen (6/8). Mycobacterial spindle cell pseudotumors show predominantly spindled morphology that may be mistaken as a neoplasm. Surgical pathologists who evaluate lymph nodes, soft tissue, and gastrointestinal tissues should be aware of this spindled tumefactive phenomenon in the setting of immunocompromised patients. Recognition of key morphologic features of neutrophilic inflammation, peripheral granulomas, or foamy histiocytes within a spindled lesion can help guide the pathologist to a correct diagnosis of an inflammatory process secondary to infection rather than a spindle cell neoplasm. Accurate diagnosis to facilitate appropriate antimicrobial and/or surgical therapy requires a comprehensive evaluation combining clinical, histopathologic, and microbiological findings.

Nutrient limitation mediates soil microbial community structure and stability in forest restoration.

Soil microorganisms are often limited by nutrients, representing an important control of heterotrophic metabolic processes. However, how nutrient limitations relate to microbial community structure and stability remains unclear, which creates a knowledge gap to understanding microbial biogeography and community changes during forest restoration. Here, we combined an eco-enzymatic stoichiometry model and high-throughput DNA sequencing to assess the potential roles of nutrient limitation on microbial community structure, assembly, and stability along a forest restoration sequence in the Qinling Mountains, China. Results showed that nutrient limitations tended to decrease during the oak forest restoration. Carbon and phosphorus limitations enhanced community dissimilarity and significantly increased bacterial alpha diversity, but not fungal diversity. Stochastic assembly processes primarily structured both bacterial (average contribution of 74.73 % and 74.17 % in bulk and rhizosheath soils, respectively) and fungal (average contribution of 77.23 % and 72.04 % in bulk and rhizosheath soils, respectively) communities during forest restoration, with nutrient limitation also contributing to the importance of stochastic processes in the bacterial communities. The migration rate (m) for bacteria was 0.19 and 0.23, respectively in both bulk soil and rhizosheath soil, and was greater than that for the fungi (m was 1.19 and 1.41, respectively), indicating a stronger dispersal limitation for fungal communities. Finally, nutrient limitations significantly affected bacterial and fungal co-occurrence with more interconnections occurring among weakly nutrient-limited microbial taxa and nutrient limitations reducing community stability when nutrient availability changed during forest restoration. Our findings highlight the fundamental effects of nutrient limitations on microbial communities and their self-regulation under changing environmental resources.

Follow-up biopsies in gastrointestinal immune checkpoint inhibitor toxicity may show markedly different inflammatory patterns than initial injury.

Colitis is a common manifestation of immune checkpoint inhibitor (ICI) toxicity and can present with varied histologic patterns of inflammation, some of which have been shown to be associated with specific ICI drug types. Although the histologic features of ICI colitis seen at the time of diagnosis have been described, there have been few reports following these patients over time. We evaluated initial and follow-up biopsies in 30 patients with ICI colitis and found that 37% of patients developed a different pattern of injury on follow-up biopsy compared to the initial biopsy. Patients with a different inflammatory pattern were more likely to have restarted ICI therapy before their follow-up biopsy (64%) compared to those without a change in inflammatory pattern (11%; P < 0.01). The majority of these patients had changed ICI drug types (86%). Additionally, many cases changed to an inflammatory bowel disease (IBD)-like pattern (36%), raising a question of de novo IBD. However, all of our patients with an IBD-like pattern experienced sustained resolution of symptoms without steroids or other immunosuppressive medications following discontinuation of ICI therapy, consistent with a diagnosis of ICI toxicity. Our findings suggest that follow-up biopsies in patients with ICI colitis may show a different histology and that this does not necessarily warrant a change in the histologic diagnosis to another disease.

STING-dependent trained immunity contributes to host defense against Clostridium perfringens infection via mTOR signaling.

Clostridium perfringens (C. perfringens) infection is recognized as one of the most challenging issues threatening food safety and perplexing agricultural development. To date, the molecular mechanisms of the interactions between C. perfringens and the host remain poorly understood. Here, we show that stimulator of interferon genes (STING)-dependent trained immunity protected against C. perfringens infection through mTOR signaling. Heat-killed Candida albicans (HKCA) training elicited elevated TNF-α and IL-6 production after LPS restimulation in mouse peritoneal macrophages (PM). Although HKCA-trained PM produced decreased levels of TNF-α and IL-6, the importance of trained immunity was demonstrated by the fact that HKCA training resulted in enhanced bacterial phagocytic ability and clearance in vivo and in vitro during C. perfringens infection. Interestingly, HKCA training resulted in the activation of STING signaling. We further demonstrate that STING agonist DMXAA is a strong inducer of trained immunity and conferred host resistance to C. perfringens infection in PM. Importantly, corresponding to higher bacterial burden, reduction in cytokine secretion, phagocytosis, and bacterial killing were shown in the absence of STING after HKCA training. Meanwhile, the high expression levels of AKT/mTOR/HIF1α were indeed accompanied by an activated STING signaling under HKCA or DMXAA training. Moreover, inhibiting mTOR signaling with rapamycin dampened the trained response to LPS and C. perfringens challenge in wild-type (WT) PM after HKCA training. Furthermore, STING­deficient PM presented decreased levels of mTOR signaling-related proteins. Altogether, these results support STING involvement in trained immunity which protects against C. perfringens infection via mTOR signaling.

Unveiling lipid-rich ("clear cell") pancreatic neuroendocrine tumor: A small series of two cases with literature review.

This study presents two cases of lipid-rich pancreatic neuroendocrine tumors (PanNETs), a rare variant posing significant diagnostic challenges in fine needle aspiration (FNA) cytology and small biopsies. The first case involves an elderly male with a pancreatic tumor, displaying distinct cytoplasmic vacuoles, while the second case is a middle-aged male present with a pancreatic tail mass exhibiting foamy cytoplasm and eccentric nuclei, infiltrating in the stroma. Both cases did not exhibit typical morphologic features of PanNET but demonstrated cytomorphologic features and infiltrative growth patterns that mimicked adenocarcinoma. Further work-up demonstrated that both tumors were immunoreactive for synaptophysin and chromogranin, and were interpreted as well-differentiated, PanNET, lipid-rich variant. The study highlights the overlapping morphological features between lipid-rich PanNETs and other pancreatic neoplasms and underscores the importance of comprehensive cytological and immunohistochemical analysis for accurately diagnosing this variant, particularly due to the risk of misinterpreting it as pancreatic adenocarcinoma. Recognizing lipid-rich PanNETs is crucial for appropriate clinical management, as their identification can significantly impact treatment decisions and patient outcomes.

TRIM28-Mediated Excessive Oxidative Stress Induces Cellular Senescence in Granulosa Cells and Contributes to Premature Ovarian Insufficiency In Vitro and In Vivo.

Premature ovarian insufficiency (POI) is a clinical syndrome of ovarian dysfunction characterized by the abnormal alteration of hormone levels such as FSH and E2. POI causes infertility, severe daily life disturbances, and long-term health risks. However, the underlying mechanism remains largely unknown. In this study, we found that POI is associated with the cellular senescence of ovarian granulosa cells, and TRIM28 mediates oxidative stress (OS)-induced cellular senescence in granulosa cells. Mechanistically, OS causes a decrease in TRIM28 protein levels in KGN cells. Subsequently, it triggers an increase in the levels of autophagy marker proteins ATG5 and LC3B-II, and the downregulation of P62. Abnormal autophagy induces an increase in the levels of cellular senescence markers γ-H2A.X, P16, and P21, provoking cellular senescence in vitro. The overexpression of ovarian TRIM28 through a microinjection of lentivirus attenuated autophagy, cellular senescence, and follicular atresia in the ovaries of POI mice and improved mouse fertility in vivo. Our study highlights the triggers for POI, where the reduction of TRIM28, which is regulated by reactive oxygen species, causes follicular atresia and POI via triggering autophagy and inducing granulosa cell senescence. Shedding light on TRIM28 may represent a potential intervention strategy for POI.

[Plant Diversity Changes and Its Driving Factors of Abandoned Land at Different Restoration Stages in the Middle of the Qinling Mountains].

The process of vegetation restoration is often accompanied by significant changes in aboveground plant diversity. To explore the driving mechanism of litter nutrient-soil nutrient-enzyme activity stoichiometry on aboveground vegetation change is of great importance for maintaining regional biodiversity conservation and ecological stability. Taking typical abandoned farmland of different restoration years （1， 8， 16， 31， and 50 a） in the Qinling Mountains as the research object， the variation characteristics of plant community diversity during vegetation restoration were analyzed through field investigation. Litter nutrients， soil nutrients， and the activities of five extracellular enzymes， including ß-1，4-glucosidase （BG）， cellobiohydrolase （CBH）， ß-1，4-N-acetylglucosaminidase （NAG）， leucine aminopeptidase （LAP）， and acid phosphatase （AP）， were determined. The characteristics of litter nutrients， soil nutrients， and enzyme stoichiometric ratios during vegetation restoration and the driving mechanism of plant diversity changes were discussed. The results showed that the plant community diversity index firstly decreased and then increased with the increase in vegetation restoration years， and the minimum was reached at 16 years after restoration. The results of principal component analysis showed that there were significant differences between total plant community diversity index and litter-soil-enzyme stoichiometric characteristics in different years of vegetation restoration. The plant community diversity index had a strong positive correlation with litter C∶P ratio and litter N∶P ratio but had a negative correlation with soil enzyme C∶P ratio （EEA C∶P）. The results of redundancy analysis showed that soil EEA C∶P had the highest explanation rate of plant diversity changes during vegetation restoration （25.93%）， followed by soil TP （5.94%）， which was the key factor regulating plant diversity changes. In conclusion， plant species and quantity increased significantly in abandoned farmland in the middle part of the Qinling Mountains at the late stage of vegetation restoration. Changes in the soil environment affected microbial metabolic activities and thus changed enzyme activities. Litter-soil-soil extracellular enzymes affected the community environment and plant diversity through feedback and regulation. EEA C∶P and TP were the main driving factors of aboveground plant diversity change during vegetation restoration.

Suppressing APOE4-induced mortality and cellular damage by targeting VHL.

Mortality rate increases with age and can accelerate upon extrinsic or intrinsic damage to individuals. Identifying factors and mechanisms that curb population mortality rate has wide-ranging implications. Here, we show that targeting the VHL-1 (Von Hippel-Lindau) protein suppresses C. elegans mortality caused by distinct factors, including elevated reactive oxygen species, temperature, and APOE4, the genetic variant that confers high risks of neurodegeneration in Alzheimer's diseases and all-cause mortality in humans. These mortality factors are of different physical-chemical nature, yet result in similar cellular dysfunction and damage that are suppressed by deleting VHL-1. Stabilized HIF-1 (hypoxia inducible factor), a transcription factor normally targeted for degradation by VHL-1, recapitulates the protective effects of deleting VHL-1. HIF-1 orchestrates a genetic program that defends against mitochondrial abnormalities, excess oxidative stress, cellular proteostasis dysregulation, and endo-lysosomal rupture, key events that lead to mortality. Genetic Vhl inhibition also alleviates cerebral vascular injury and synaptic lesions in APOE4 mice, supporting an evolutionarily conserved mechanism. Collectively, we identify the VHL-HIF axis as a potent modifier of APOE4 and mortality and propose that targeting VHL-HIF in non-proliferative animal tissues may suppress tissue injuries and mortality by broadly curbing cellular damage.

Co-exposure to polystyrene nanoplastics and triclosan induces synergistic cytotoxicity in human KGN granulosa cells by promoting reactive oxygen species accumulation.

In recent years, nanoplastics (NPs) and triclosan (TCS, a pharmaceutical and personal care product) have emerged as environmental pollution issues, and their combined presence has raised widespread concern regarding potential risks to organisms. However, the combined toxicity and mechanisms of NPs and TCS remain unclear. In this study, we investigated the toxic effects of polystyrene NPs and TCS and their mechanisms on KGN cells, a human ovarian granulosa cell line. We exposed KGN cells to NPs (150 µg/mL) and TCS (15 µM) alone or together for 24 hours. Co-exposure significantly reduced cell viability. Compared with exposure to NPs or TCS alone, co-exposure increased reactive oxygen species (ROS) production. Interestingly, co-exposure to NPs and TCS produced synergistic effects. We examined the activity of superoxide dismutase (SOD) and catalase (CAT), two antioxidant enzymes; it was significantly decreased after co-exposure. We also noted an increase in the lipid oxidation product malondialdehyde (MDA) after co-exposure. Furthermore, co-exposure to NPs and TCS had a more detrimental effect on mitochondrial function than the individual treatments. Co-exposure activated the NRF2-KEAP1-HO-1 antioxidant stress pathway. Surprisingly, the expression of SESTRIN2, an antioxidant protein, was inhibited by co-exposure treatments. Co-exposure to NPs and TCS significantly increased the autophagy-related proteins LC3B-II and LC3B-Ⅰ and decreased P62. Moreover, co-exposure enhanced CASPASE-3 expression and inhibited the BCL-2/BAX ratio. In summary, our study revealed the synergistic toxic effects of NPs and TCS in vitro exposure. Our findings provide insight into the toxic mechanisms associated with co-exposure to NPs and TCS to KGN cells by inducing oxidative stress, activations of the NRF2-KEAP1-HO-1 pathway, autophagy, and apoptosis.