NAD + salvage governs mitochondrial metabolism, invigorating natural killer cell antitumor immunity.

BACKGROUND AND AIMS: Natural killer (NK) cells are key players in tumor immunosurveillance, and metabolic adaptation manipulates their fate and functional state. The nicotinamide adenine dinucleotide (NAD + ) has emerged as a vital factor to link cellular metabolism and signaling transduction. Here, we identified NAD + metabolism as a central hub to determine the homeostasis and function of NK cells. APPROACH AND RESULTS: NAD + level was elevated in activated NK cells. NAD + supplementation not only enhanced cytokine production and cytotoxicity but also improved the proliferation and viability of NK cells. Intriguingly, the salvage pathway was involved in maintaining NAD + homeostasis in activated NK cells. Genetic ablation or pharmacological blockade of nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme in the NAD + salvage pathway, markedly destroyed the viability and function of NK cells. Mechanistically, NAD + salvage dictated the mitochondrial homeostasis and oxidative phosphorylation activity to support the optimal function of NK cells. However, in human HCC tissues, NAMPT expression and NAD + level were significantly down-regulated in tumor-infiltrating NK cells, which negatively correlated with patient survival. And lactate accumulation in the tumor microenvironment was at least partially responsible for the transcriptional repression of NAMPT in NK cells. Further, deficiency of Nampt in NK cells accelerated the growth of HCC and melanoma. Supplementation of the NAD + precursor nicotinamide mononucleotide (NMN) significantly improved NK antitumor response in both mouse and human cell-derived xenografts. CONCLUSIONS: These findings reveal NAD + salvage as an essential factor for NK-cell homeostasis and function, suggesting a potential strategy for invigorating NK cell-based immunotherapy.

Heavy metal contamination assessment and source attribution in the Vicinity of an iron slag pile in Hechi, China: Integrating multi-medium analysis.

Heavy metals, such as mercury, cadmium, and nickel, may contaminate human inhabited environments, with critical consequences for human health. This study examines the health impacts of heavy metal pollution from an iron slag pile in Hechi, China, by analyzing heavy metal contamination in water, sediment, soil, and crops. Here, the Nemerow pollution index (NI) indicated severe pollution at most sampling sites, the mean NI of groundwater, and surface water had reached 594.13 and 26.79, respectively. Bioaccumulation of mercury (Hg), cadmium (Cd), and nickel (Ni) was noted in crops, cucumbers showed comparatively lower risk levels. Logarithmic surface water-sediment partition coefficient calculations indicated that heavy metals such as chromium (Cr), ferrum (Fe), zinc (Zn), copper (Cu), Ni, arsenic (As), and lead (Pb) tend to accumulate in sediments. There was a high risk in groundwater (67.48-6590.54) and surface water (13.73-2500.85). Variably influenced by rainfall, these metals can be diluted and mobilized from surface water and sediments, thereby changing the contamination levels and ecological risks. Probabilistic health risk assessments indicated that health risks were higher in children than in adults, the mean total carcinogenic risk values of soil, groundwater, and surface water, were 6.79E-04, 4.20E-06, and 1.15E-6 for children, respectively. Moderate soil pollution is the main health hazard. A Positive Matrix Factorization model attributed over 60% of the pollution to slag stacking. Biotechnologies, solidification/stabilization techniques, field management, and institutional controls, driven by principles of green, low-carbon, and economic efficiency may mitigate. These findings contribute to the management of heavy metal pollution in iron slag pile areas.

Clinical Results of Asymmetric Blepharoplasty Plastic Repair.

OBJECTIVE: To investigate plastic surgery repair's effects and adverse reactions in the clinical therapy of asymmetric double eyelids. METHODS: All 126 sufferers who came to the hospital for asymmetric double eyelid plastic repair from January 2022 to October 2022 were selected as the research objects, and they were divided into a control group and an observation group using the random number method, with 63 cases in each group, in which sufferers in the control group underwent full incision blepharoplasty and sufferers in the observation group underwent small incision liposuction with submerged sutures. The general data, treatment results, treatment satisfaction, related surgical indicators, and frequency of adverse reactions of the 2 groups of sufferers with asymmetric double eyelid plastic repair were compared. RESULTS: It had no statistically obvious distinction between the control group and the observation group of sufferers in terms of general data such as sex, age, weight, and height ( P> 0.05); the total therapy efficiency of the sufferers in the observation group (95.24%) was greater than the control group (74.60%), with P value <0.05; the total treatment satisfaction of the patients in the observation group (96.83%) was significantly higher than that in the control group (76.19%), with P value <0.05; compared with the control group, patients in the observation group had shorter operative time and healing time and less intraoperative bleeding, with P value < 0.05; the total frequency of adverse reactions of sufferers in the observation group (4.76%) was less than the control group (17.46%), with P value < 0.05. CONCLUSION: Small incision liposuction with submerged sutures for plastic repair has significant efficacy, relatively high patient satisfaction, and low incidence of adverse reactions, in line with patient esthetic review, which has a broad clinical application prospect.

Complications After Prepectoral Versus Subpectoral Breast Reconstruction in Patients Receiving Postmastectomy Radiation Therapy: A Systematic Review and Meta-Analysis.

BACKGROUND: Outcomes of immediate breast reconstructions can be influenced by postoperative radiotherapy. However, there is no clarity on the use of prepectoral or subpectoral breast reconstruction in the setting of postmastectomy radiation therapy (PMRT). We reviewed evidence on the complication rates of prepectoral and subpectoral breast reconstruction in women undergoing PMRT. METHODS: PubMed, Web of Science, and Embase databases were scanned for studies comparing complication rates of prepectoral and subpectoral breast reconstruction with PMRT. All complications were pooled in a random-effect meta-analysis to obtain odds ratio (OR). RESULTS: Eight observational studies were included. Meta-analysis showed no difference in the risk of infections (OR: 1.22 95% CI 0.79, 1.88 I2=0%), implant loss (OR: 0.86 95% CI 0.50, 1.50 I2=14%), seroma (OR: 1.01 95% CI 0.43, 2.34 I2=50%), hematoma (OR: 0.44 95% CI 0.12, 1.71 I2=0%), wound dehiscence (OR: 0.95 95% CI 0.42, 2.17 I2=0%), and skin necrosis (OR: 0.61 95% CI 0.21, 1.75 I2=36%), contracture (OR: 0.46 95% CI 0.15, 1.48 I2=54%) and the need for revision surgeries (OR: 0.85 95% CI 0.45, 1.60 I2=15%) between the prepectoral and subpectoral groups. CONCLUSIONS: Data from observational studies indicates that in appropriately selected patients there may not be any difference in the risk of early complications with prepectoral or subpectoral breast reconstruction with PMRT. Current evidence is limited by the small number of studies, short follow-up and selection bias. There is a need for randomized controlled trials comparing the two approaches to obtain robust evidence on long-term outcomes. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to Table of Contents or the online Instructions to Authors www.springer.com/00266 .

SREBF2-STARD4 axis confers sorafenib resistance in hepatocellular carcinoma by regulating mitochondrial cholesterol homeostasis.

Sorafenib resistance limits its survival benefit for treatment of hepatocellular carcinoma (HCC). Cholesterol metabolism is dysregulated in HCC, and its role in sorafenib resistance of HCC has not been fully elucidated. Aiming to elucidate this, in vitro and in vivo sorafenib resistant models were established. Sterol regulatory element binding transcription factor 2 (SREBF2), the key regulator of cholesterol metabolism, was activated in sorafenib resistant HepG2 and Huh7 cells. Knockdown of SREBF2 resensitized sorafenib resistant cells and xenografts tumors to sorafenib. Further study showed that SREBF2 positively correlated with StAR related lipid transfer domain containing 4 (STARD4) in our sorafenib resistant models and publicly available datasets. STARD4, mediating cholesterol trafficking, not only promoted proliferation and migration of HepG2 and Huh7 cells, but also increased sorafenib resistance in liver cancer. Mechanically, SREBF2 promoted expression of STARD4 by directly binding to its promoter region, leading to increased mitochondrial cholesterol levels and inhibition of mitochondrial cytochrome c release. Importantly, knockdown of SREBF2 or STARD4 decreased mitochondrial cholesterol levels and increased mitochondrial cytochrome c release, respectively. Moreover, overexpression of STARD4 reversed the effect of SREBF2 knockdown on mitochondrial cytochrome c release and sorafenib resistance. In conclusion, SREBF2 promotes STARD4 transcription, which in turn contributes to mitochondrial cholesterol transport and sorafenib resistance in HCC. Therefore, targeting the SREBF2-STARD4 axis would be beneficial to a subset of HCC patients with sorafenib resistance.

Highly Diastereoselective One-Pot Synthesis of 4,5-Dihydrofuro[2,3-b]azocin-6-one Derivatives through Cyclization/[4+4] Annulation Reactions.

A variety of 4,5-dihydrofuro[2,3-b]azocin-6-one derivatives were expediently assembled through Au(I)-catalyzed cyclization and 2-(tert-butyl)-1,1,3,3-tetramethylguanidine (BTMG)-mediated [4+4] annulation reactions of enyne-amides and ynones. The reactions exhibit high efficiency with excellent regio- and diastereoselectivity. A broad spectrum of substrates was utilized. The products with an eight-membered ring might be useful in biological chemistry and medicinal science. Furthermore, the products could be facilely converted into various derivatives.

ZHX2 inhibits thyroid cancer metastasis through transcriptional inhibition of S100A14.

BACKGROUND: Thyroid cancer is the most common malignant endocrine tumour, and metastasis has become the main reason for treatment failure. However, the underlying molecular mechanism of thyroid cancer metastasis remains poorly understood. We investigated the role of the tumour suppressor zinc fingers and homeoboxes 2 (ZHX2) in the metastasis of thyroid cancer. METHODS: To study the role of ZHX2 in thyroid cancer metastasis, we evaluated the EMT process using cell migration, wound healing and lung metastatic tumour formation in vitro and in vivo models. RESULTS: ZHX2 expression was significantly decreased in thyroid cancer tissues, which correlated with poor prognosis of thyroid cancer patients. ZHX2 knockdown significantly promoted the migration of thyroid cancer cells. Mechanistically, ZHX2 associated with the S100 calcium binding protein A14 (S100A14) promoter to decrease the transcription of S100A14. Moreover, S100A14 was highly expressed in human thyroid cancer samples, and its expression negatively correlated with ZHX2 expression. CONCLUSIONS: Inhibition of S100A14 attenuated the ZHX2 knockdown-induced enhanced metastasis of thyroid cancer cells both in vitro and in vivo. The evidence presented here suggests that ZHX2 inhibits the progression of thyroid cancer by blocking S100A14-mediated metastasis.

Zhx2 Accelerates Sepsis by Promoting Macrophage Glycolysis via Pfkfb3.

Sepsis is a life-threatening condition with limited therapeutic options, characterized as excessive systemic inflammation and multiple organ failure. Macrophages play critical roles in sepsis pathogenesis. Metabolism orchestrates homeostasis of macrophages. However, the precise mechanism of macrophage metabolism during sepsis remains poorly elucidated. In this study, we identified the key role of zinc fingers and homeoboxes (Zhx2), a ubiquitous transcription factor, in macrophage glycolysis and sepsis by enhancing 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (Pfkfb3) expression. Mice with myeloid Zhx2-specific deletion (abbreviated as MKO) showed more resistance to cecal ligation and puncture and LPS-induced sepsis, exhibiting as prolonged survival, attenuated pulmonary injury, and reduced level of proinflammatory cytokines, such as TNF-α, IL-6, and IL-1ß. Interestingly, Zhx2 deletion conferred macrophage tolerance to LPS-induced glycolysis, accompanied by reduced proinflammatory cytokines and lactate. Consistently, treatment of glycolytic inhibitor 2-deoxyglucose almost completely abrogated the protection of mice from LPS-induced sepsis initiated by Zhx2 deletion in macrophages. RNA sequencing and chromatin immunoprecipitation assays confirmed that Zhx2 enhanced transcription of Pfkfb3, the glycolysis rate-limiting enzyme, via binding with Pfkfb3 promoter. Furthermore, Pfkfb3 overexpression not only rescued the reduction of macrophage glycolysis caused by Zhx2 deficiency, displaying as extracellular acidification rates and lactate production but also destroyed the resistance of mice to LPS-induced sepsis initiated by transfer of bone marrow-derived macrophages from MKO mice. These findings highlight the novel role of transcription factor Zhx2 in sepsis via regulating Pfkfb3 expression and reprogramming macrophage metabolism, which would shed new insights into the potential strategy to intervene sepsis.

Effects of COVID-19 and mRNA vaccines on human fertility.

The coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has precipitated a global health crisis of unprecedented proportions. Because of its severe impact, multiple COVID-19 vaccines are being rapidly developed, approved and manufactured. Among them, mRNA vaccines are considered as ideal candidates with special advantages to meet this challenge. However, some serious adverse events have been reported after their application, significantly increasing concerns about the safety and efficacy of the vaccines and doubts about the necessity of vaccination. Although several fertility societies have announced that COVID-19 mRNA vaccines are unlikely to affect fertility, there is no denying that the current evidence is very limited, which is one of the reasons for vaccine hesitancy in the population, especially in pregnant women. Herein, we provide an in-depth discussion on the involvement of the male and female reproductive systems during SARS-CoV-2 infection or after vaccination. On one hand, despite the low risk of infection in the male reproductive system or fetus, COVID-19 could pose an enormous threat to human reproductive health. On the other hand, our review indicates that both men and women, especially pregnant women, have no fertility problems or increased adverse pregnancy outcomes after vaccination, and, in particular, the benefits of maternal antibodies transferred through the placenta outweigh any known or potential risks. Thus, in the case of the rapid spread of COVID-19, although further research is still required, especially a larger population-based longitudinal study, it is obviously a wise option to be vaccinated instead of suffering from serious adverse symptoms of virus infection.

Effect of a "Zn Bridge" on the Consecutively Tunable Retention Characteristics of Volatile Random Access Memory Materials.

Polyimide memory materials with a donor-acceptor structure based on a charge-transfer mechanism exhibit great potential for next-generation information storage technology due to their outstanding high-temperature resistance and good dimensional and chemical stability. Precisely controlling memory performance by limited chemical decoration is one of core challenges in this field. Most reported work mainly focuses on designing novel and elaborate electron donors or acceptors for the expected memory behavior of polyimides; this takes a lot of time and is not always efficacious. Herein, we report a series of porphyrinated copolyimides coPI-Znx (x=5, 10, 20, 50, 80), where x represents the mole percentage of Zn ion in the central core of the porphyrin. Experimental and theoretical analysis indicate that the Zn ion could play a vital bridge role in promoting the formation and stabilization of a charge-transfer complex by enhancing the hybridization of local and charge transfer (HLCT) excitations of porphyrinated polyimides, endowing coPI-Znx with volatile random access memory performance and continuously tunable retention time. This work could provide one simple strategy to precisely regulate memory performance merely by altering the metal content in porphyrinated polyimides.

ZHX2 inhibits SREBP1c-mediated de novo lipogenesis in hepatocellular carcinoma via miR-24-3p.

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death worldwide. Lipogenesis has been considered as a critical player in HCC initiation and progression. However, the underlying mechanism is still not fully understood. Here, we identified zinc fingers and homeoboxes 2 (ZHX2), an HCC-associated tumor suppressor, as an important repressor of de novo lipogenesis. Ectopic expression of ZHX2 significantly inhibited de novo lipogenesis in HCC cells and decreased expression of FASN, ACL, ACC1, and SCD1. In accordance with this, ZHX2 was negatively associated with SREBP1c, the master regulator of de novo lipogenesis, in HCC cell lines and human specimens. Results from silencing and overexpression demonstrated that ZHX2 inhibited de novo lipogenesis and consequent HCC progression via repression of SREBP1c. Furthermore, treatment with the SREBP1c inhibitor fatostatin dampened the spontaneous formation of tumors in liver-specific Zhx2 knockout mice. Mechanistically, ZHX2 increased expression of miR-24-3p transcriptionally, which targeted SREBP1c and led to its degradation. In conclusion, our data suggest a novel mechanism through which ZHX2 suppresses HCC progression, which may provide a new strategy for the treatment of HCC. © 2020 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Concurrent tuberculous chorioretinitis with choroidal neovascularization and tuberculous meningitis: a case report.

BACKGROUND: Tuberculosis (TB) remains a severe health burden worldwide. The manifestation of concurrent tuberculous cerebral and ocular involvements associated with TB is uncommon. CASE PRESENTATION: We report a 17-year-old girl with concurrent tuberculous cerebral and ocular involvements and visual impairment due to choroidal neovascularization. This study emphasizes the definite diagnosis with the combination of ophthalmological examination, multimodal imaging and routine tuberculosis testing, and the proper management with intravitreal anti-VEGF injection accompanied by systemic anti-tuberculosis therapy. CONCLUSION: Combined applications of routine TB tests, fundus multimodal imaging and diagnostic therapy greatly help the clinician to establish a precise diagnosis and in monitoring the therapeutic response.

Clinical Application of Earlobe Augmentation with Hyaluronic Acid Filler in the Chinese Population.

BACKGROUND: Larger earlobes, which are a symbol of "richness" in traditional Chinese culture, are favored by Chinese patients. The objective of this paper is to investigate the application of earlobe augmentation with hyaluronic acid (HA) filler injection and its clinical effects in the Chinese population. METHODS: A total of 19 patients (38 ears) who received earlobe augmentation with HA filler injections between March 2013 and March 2015 were included. The clinical effects, duration, and complications of these cases were investigated. RESULTS: All patients who received earlobe HA injections showed immediate postoperative effects with obvious morphological improvement of their earlobes. The volume of HA filler injected into each ear was 0.3-0.5 ml. The duration of the effect was 6-9 months. Two of the 19 cases (3 ears) demonstrated mild bruising at the injection site, but the bruising completely disappeared within 7 days after the injection. No vascular embolism, infection, nodule, or granuloma complications were observed in the studied group. CONCLUSION: The application of earlobe augmentation with HA filler injection is a safe, effective, simple procedure for earlobe shaping. It has an easy clinical application with good clinical prospects. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Application of Local Injection of Botulinum Toxin A in Cosmetic Patients with Congenital Drooping Mouth Corner.

OBJECTIVE: This study aimed to investigate the clinical application and efficacy of local injection of botulinum toxin A (BTX-A) at the depressor anguli oris in patients with congenital drooping mouth corner. METHODS: From September 2013 to March 2015, 36 cosmetic patients received local injections of botulinum toxin A at the depressor anguli oris, with 1-3 injection sites in the moving region of the depressor anguli oris on each side. At each injection site, 2-4 U of BTX-A was injected, and the total dose for any unilateral treatment did not exceed 8 U. The change in the degree of drooping of the mouth corner before and after the injection was analyzed using statistical methods. The clinical efficacy, preservation time, and adverse reactions were observed. RESULTS: The degree of drooping of the mouth corners of the cosmetic patients before the treatment was compared with that at 1 month after using a paired t test, and the difference was statistically significant, with P < 0.01. The treatment results were satisfactory, and the effect was preserved for 6-9 months. None of the 36 cosmetic patients had any complications of bruising, infection, dysfunction in opening and closing the mouth, smile asymmetry, drooling, or dysarthria after the injection. CONCLUSIONS: The local injection of BTX-A at the depressor anguli oris can effectively lift a drooping mouth corner, thereby improving the depressed, stern, and aged appearance of the face. The performance of this treatment is simple, safe, and easy to perform in clinical applications. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Chronic exposure to low concentrations of microplastics causing gut tissue damage but non-significant changes in the microbiota of marine medaka larvae (Oryzias melastigma).

Microplastics (MPs) have become a popular research topic due to their potential ramifications on aquatic organisms. To evaluate the ecotoxicological impacts of chronic exposure to different microplastics on marine medaka larvae, we exposed medaka larvae to 200 µg/L of polyethylene (PE-200) and polylactic acid (PLA-200) microplastics for 60 days, respectively. The results indicated that both exposures had no significant effect on fish length/weight and did not result in fish mortality. Notably, the structure of intestinal microbiota was not disrupted either. However, microscopy observations of intestinal tissue suggested that exposure to MPs resulted in inflammation of the intestinal tract of fish and significant atrophy and shedding of small intestinal villus. Linear discriminant analysis Effect Size (LEfSe) showed that intestinal enrichment of Streptomyces occurred in marine medaka larvae in both MPs treatments, while the PE-200 treatment exhibited a significant enrichment. In addition, the PICRUSt2 prediction indicated significant upregulation of the Novobiocin biosynthesis function in gut microbiota in the PE-200 treatment. Overall, multi-level assessment is necessary to determine the risk of exposure of aquatic organisms to MPs.

Construction of Immune-Related Diagnostic Model for Latent Tuberculosis Infection and Active Tuberculosis.

Background: Tuberculosis (TB) is one of the most infectious diseases caused by Mycobacterium tuberculosis (M. tb), and the diagnosis of active tuberculosis (TB) and latent TB infection (LTBI) remains challenging. Methods: Gene expression files were downloaded from the GEO database to identify the differentially expressed genes (DEGs). The ssGSEA algorithm was applied to assess the immunological characteristics of patients with LTBI and TB. Weighted gene co-expression network analysis, protein-protein interaction network, and the cytoHubba plug-in of Cytoscape were used to identify the real hub genes. Finally, a diagnostic model was constructed using real hub genes and validated using a validation set. Results: Macrophages and natural killer cells were identified as important immune cells strongly associated with TB. In total, 726 mRNAs were identified as DEGs. MX1, STAT1, IFIH1, DDX58, and IRF7 were identified as real hub immune-related genes. The diagnostic model generated by the five real hub genes could distinguish active TB from healthy controls or patients with LTBI. Conclusion: Our study may provide implications for the diagnosis and drug development of M. tb infections.

Distribution characteristics of antibiotic resistance genes and microbial diversity in the inshore aquaculture area of Wenchang, Hainan, China.

The rapid development of marine aquaculture has led to the increased use and release of antibiotics into the marine environment, consequently contributing to the emergence of antibiotic resistance. Information on antibiotic resistance in nearshore marine aquaculture areas remains limited, and research on the microbial composition and potential hosts of antibiotic resistance genes (ARGs) in marine aquaculture areas is scarce. This study used SmartChip real-time fluorescent quantitative PCR and qPCR to quantitatively analyze 44 ARGs and 10 mobile genetic elements (MGEs) genes in 12 sampling points in the nearshore aquaculture area of Wenchang. High-throughput sequencing of 16S rRNA was used to study microbial diversity in the study area, to clarify the correlation between ARGs, MGEs, and microbial diversity, and to determine the possible sources and potential hosts of ARGs. The results showed that a total of 37 ARGs and 8 MGEs were detected in the study area. The detection rate of 9 ARGs (aac(6')-Ib(aka aacA4)-02, catA1, cmlA, cfr, sul1, sul2, sulA/folP-01, tetC, tetX) was 100 %. The absolute abundance of ARGs in the 12 sampling points ranged from 2.75 × 107 to 3.79 × 1010 copies·L-1, and the absolute abundance of MGEs was 1.30 × 105 to 2.54 × 107 copies·L-1, which was relatively high compared to other research areas. ARGs and MGEs were significantly correlated, indicating that MGEs play an important role as a mediator in the spread of ARGs. At the phylum level, Proteobacteria and Cyanobacteria were the dominant bacteria in the study area, with HIMB11 and unidentifiedChloroplast being the dominant levels, respectively. Network analysis of ARGs and microorganisms (genus level) revealed that Cognatishimia, Thalassobius, Aestuariicoccus, Thalassotalea, and Vibrio were significantly correlated with multiple ARGs and were the main potential hosts of ARGs in the nearshore waters of Wenchang.

Regional distribution differences of antibiotics in tropical marine aquaculture area: Insights into antibiotic management and risk assessment.

In recent years, global demand for marine aquaculture products has led to a significant rise in antibiotic use, particularly in tropical coastal aquaculture areas However, research on antibiotic residues in these environments remains limited, hindering a comprehensive understanding of their environmental presence and associated risks. This study investigates the regional distribution, ecological risks, and sources of 44 antibiotics in seawater across four coastal aquaculture areas in Hainan island (Wenchang, Sanya, Danzhou, and Wanning). Among the 44 antibiotics tested across 42 sampling sites, all were detected with a 100 % detection rate. Antibiotics such as Trimethoprim (TMP), Sulfanitran (APNPS), Sulfaquinoxaline (SQ), Sulfadimethoxine (SDT), Chloramphenicol (CHP), and Florfenicol (FLO) were consistently detected across all sampling sites. Total concentrations of detected antibiotics ranged from 0 to 818.79 ng.L-1, with sulfonamide antibiotics ranging from 0 to 629.49 ng.L-1, chloramphenicol antibiotics from 0 to 87.39 ng.L-1, tetracyclines from 0 to 221.39 ng.L-1, and fluoquinolones from 0 to 272.08 ng.L-1. The highest levels of antibiotic pollution were observed at the W5 sampling site in Wenchang, attributed to aquaculture wastewater discharge, while no antibiotics were found at D12 in Danzhou. In these regions, source analysis identified aquaculture and domestic sewage as the primary contributors to antibiotic pollution in these regions. Correlation analysis with environmental factors revealed significant influences of factors such as SAL, kPa, TN, SPC, and pH on sulfonamide and chloramphenicol antibiotics. Health risk assessment indicated moderate to high risks to aquatic organisms from antibiotics like NOR, CIP, ENR, OFL, TMP, and SMX in the study areas, underscoring the need for preventive measures, stricter regulation of antibiotic use, and enhanced ecological risk monitoring in aquaculture regions. This study provides critical insights into antibiotic contamination in Hainan's coastal aquaculture areas, highlighting the urgent need for further research into the occurrence and ecological impacts of these emerging pollutants in marine environments.

Aerobic Fe transformation induced decrease in the adsorption and enhancement in the reduction of Cr(VI) by humic acid-ferric iron coprecipitates.

Humic substance (HS)-ferric iron (Fe(III)) coprecipitates are widespread organo-mineral associations in soils and aquifers and have the capacity to immobilize and detoxify Cr(VI). These coprecipitates undergo transformation owing to their thermodynamic instability; however, the effects of this transformation on their environmental behaviors remain unclear, particularly in aerobic environments. In this study, the aerobic transformation of humic acid (HA)-Fe(III) coprecipitates, a representative of HS-Fe(III) coprecipitates, was simulated. The environmental effect was then evaluated after conducting an adsorption-reduction batch experiment toward Cr(VI). The aerobic transformation characteristics, as well as the adsorption/reduction capacity of HA-Fe(III) coprecipitates, were found to depend strongly on their structures. In ferrihydrite (Fh)-like coprecipitates, amorphous Fh is readily transformed into crystalline hematite and goethite at aerobic environments, leading to a much lower specific surface area and adsorption capacity. However, this increasing degree of crystallization enhanced the inductive reduction ability towards Cr(VI) owing to the more significant shift of electron pairs in the FeOC bond toward the HA direction. In HS-like coprecipitates, Fe(III) always serves as a cation bridge connecting HA molecules, but can be reduced to Fe(II) by the associated HA after aerobic transformation. The produced Fe(II), therefore, drove the reduction of the adsorbed Cr(VI). These findings emphasize the pivotal role of aerobic transformation in enhancing the reduction capacity for Cr(VI), which opens a new avenue for the development of in-situ remediation agents for Cr(VI)-contaminated sites.