The Effects of Irradiation on the Improvement in Oxidation Behavior of MX-ODS Steel in Liquid Pb.

Lead-cooled fast reactors exhibit strong inherent safety performance and good economic features, while material degradation due to corrosion and irradiation is still challenging. Oxide dispersion-strengthened steels are one of the promising candidates for fuel cladding materials. The effects of both irradiation and corrosion on ODS steel need to be further studied. In this work, MX-ODS steel was irradiated by Fe ions at 500 °C up to 46 dpa. Later, the as-received specimen and the irradiated specimen were used to conduct corrosion tests in oxygen-saturated Pb at 550 °C for 1 h. In the as-received specimen, discontinuous oxides penetrated by Pb and Pb in contact with steel matrix were observed, demonstrating unsatisfactory corrosion resistance of the material. However, in the irradiated specimen after corrosion experiment, a protective oxide layer formed and prevented Pb attack. The oxidation behavior differences between the two specimens can be attributed to the defects produced by irradiation and the structural discrepancy in oxides caused by the formation process. A possible mechanism of irradiation on the corrosion is discussed. In the as-received specimen, Fe atoms loss led to voids in the oxides, and lead penetrated the oxides through these voids. In the irradiated specimen, defects left by previous irradiation helped to form a more uniform oxide layer. The adhesive outer magnetite oxide and the Fe ions generated from where grain boundary oxidation developed retarded the presence of voids and made the oxide layer protective.

Association between ideal cardiovascular health and abnormal glucose metabolism in the elderly: evidence based on real-world data.

BACKGROUND: Limited information is available on the effect of ideal cardiovascular health (CVH) and abnormal glucose metabolism in elderly people. We aimed to analyze the prevalence of CVH behaviors, abnormal glucose metabolism, and their correlation in 65 and older people. METHODS: In this study, randomized cluster sampling, multivariate logistic regression, and mediating effects analysis were used. Recruiting was carried out between January 2020 and December 2020, and 1984 participants aged 65 years or older completed the study. RESULTS: The prevalence of abnormal glucose metabolism in this group was 26.7% (n = 529), among which the prevalence of impaired fasting glucose (IFG) was 9.5% (male vs. female: 8.7% vs 10.1%, P = 0.338), and the prevalence of type 2 diabetes mellitus (T2DM) was 19.0% (male vs. female: 17.8 vs. 19.8%, P = 0.256). The ideal CVH rate (number of ideal CVH metrics ≥ 5) was only 21.0%. The risk of IFG and T2DM decreased by 23% and 20% with each increase in one ideal CVH metrics, with OR (95%CI) of 0.77(0.65-0.92) and 0.80(0.71-0.90), respectively (P -trend < 0.001). TyG fully mediated the ideal CVH and the incidence of T2DM, and its mediating effect OR (95%CI) was 0.88(0.84-0.91). CONCLUSIONS: Each increase in an ideal CVH measure may effectively reduce the risk of abnormal glucose metabolism by more than 20%.

Distinct roles of excitatory and inhibitory neurons in the medial prefrontal cortex in the expression and reconsolidation of methamphetamine-associated memory in male mice.

Methamphetamine, a commonly abused drug, is known for its high relapse rate. The persistence of addictive memories associated with methamphetamine poses a significant challenge in preventing relapse. Memory retrieval and subsequent reconsolidation provide an opportunity to disrupt addictive memories. However, the key node in the brain network involved in methamphetamine-associated memory retrieval has not been clearly defined. In this study, using the conditioned place preference in male mice, whole brain c-FOS mapping and functional connectivity analysis, together with chemogenetic manipulations of neural circuits, we identified the medial prefrontal cortex (mPFC) as a critical hub that integrates inputs from the retrosplenial cortex and the ventral tegmental area to support both the expression and reconsolidation of methamphetamine-associated memory during its retrieval. Surprisingly, with further cell-type specific analysis and manipulation, we also observed that methamphetamine-associated memory retrieval activated inhibitory neurons in the mPFC to facilitate memory reconsolidation, while suppressing excitatory neurons to aid memory expression. These findings provide novel insights into the neural circuits and cellular mechanisms involved in the retrieval process of addictive memories. They suggest that targeting the balance between excitation and inhibition in the mPFC during memory retrieval could be a promising treatment strategy to prevent relapse in methamphetamine addiction.

Bouncing Dynamics of Drops' Successive Off-Center Impact.

Bouncing dynamics of a trailing drop off-center impacting a leading drop with varying time intervals and Weber numbers are investigated experimentally. Whether the trailing drop impacts during the spreading or receding process of the leading drop is determined by the time interval. For a short time interval of 0.15 ≤ Δt* ≤ 0.66, the trailing drop impacts during the spreading of the leading drop, and the drops completely coalesce and rebound; for a large time interval of 0.66 < Δt* ≤ 2.21, the trailing drop impacts during the receding process, and the drops partially coalesce and rebound. Whether the trailing drop directly impacts the surface or the liquid film of the leading drop is determined by the Weber number. The trailing drop impacts the surface directly at moderate Weber numbers of 16.22 ≤ We ≤ 45.42, while it impacts the liquid film at large Weber numbers of 45.42 < We ≤ 64.88. Intriguingly, when the trailing drop impacts the surface directly or the receding liquid film, the contact time increases linearly with the time interval but independent of the Weber number; when the trailing drop impacts the spreading liquid film, the contact time suddenly increases, showing that the force of the liquid film of the leading drop inhibits the receding of the trailing drop. Finally, a theoretical model of the contact time for the drops is established, which is suitable for different impact scenarios of the successive off-center impact. This study provides a quantitative relationship to calculate the contact time of drops successively impacting a superhydrophobic surface, facilitating the design of anti-icing surfaces.

Ideal cardiovascular health index and high-normal blood pressure in elderly people: evidence based on real-world data.

Limited information is available on the cardiovascular health (CVH) index and risk of high-normal blood pressure (HNBP) in elderly people. Randomized cluster sampling, multivariate logistic regression, and mediating effects analysis were used in this study analyze the relationship between CVH index and HNBP in the elderly. 1089 non-hypertensive residents aged 65 years or older completed the study. The positive rate of HNBP was 75.85% (male vs. female: 76.13% vs. 75.64%, P = 0.852); The ideal rate of CVH (ideal CVH index ≥ 5 items) was 14.51% (male vs. female: 15.91% vs. 13.46%, P = 0.256). Compared with people with 0-2 ideal CVH index, the risk of HNBP in people with 4 ideal indexes and ≥ 5 ideal indexes decreased by 50% and 63%, respectively, and their OR (95% CI) were 0.50 (0.31, 0.81) and 0.37 (0.21, 0.66), respectively. The results of the trend test showed that the risk of HNBP decreased by 32% for every increase in the ideal CVH index (trend P < 0.001) and TyG index does not play a mediating role in this relationship. That is, increasing the number of ideal CVH index may effectively reduce the risk of HNBP in elderly by one-third.

Revealing the interaction forms between Hg(II) and group types (-Cl, -CN, -NH2, -OH, -COOH) in functionalized Poly(pyrrole methane)s for efficient mercury removal.

To explore the impact of different functional groups on Hg(II) adsorption, a range of poly(pyrrole methane)s functionalized by -Cl, -CN, -NH2, -OH and -COOH were synthesized and applied to reveal the interaction between different functional groups and mercury ions in water, and the adsorption mechanism was revealed through combined FT-IR, XPS, and DFT calculations. The adsorption performance can be improved to varying degrees by the incorporation of functional groups. Among them, the oxygen-containing functional groups (-OH and -COOH) exhibit stronger affinity for Hg(II) and can increase the adsorption capacity from 180 mg g-1 to more than 1400 mg g-1 at 318 K, with distribution coefficient (Kd) exceeding 105 mL g-1. The variations in the capture and immobilization capabilities of functionalized poly(pyrrole methane)s predominantly stem from the unique interactions between their functional groups and mercury ions. In particular, oxygen-containing -OH and -COOH effectively capture Hg(OH)2 through hydrogen bonding, and further deprotonate to form the -O-Hg-OH and -COO-Hg-OH complexes which are more stable than those obtained from other functionalized groups. Finally, the ecological safety has been fully demonstrated through bactericidal and bacteriostatic experiments to prove the functionalized poly(pyrrole methane)s can be as an environmentally friendly adsorbent for purifying contaminated water.

Emerging approaches to male contraception.

BACKGROUND: Currently, approximately half of all pregnancies worldwide are unintended. Contraceptive use significantly reduces the risk of unintended pregnancy; however, options for men are particularly limited. Consequently, efforts are underway to develop novel, safe, and effective male contraceptives. RESULTS: This review discusses research into emerging male contraceptive methods that either inhibit sperm production or impair sperm function. It focuses on those in the preclinical or early clinical stages of development.

Visualizing Motion Trail via Phosphorescence Carbon Nanodots-Based Delay Display Array.

A scene that contains both old and instant events with a clear motion trail is visually intriguing and dynamic, which can convey a sense of change, transition, or evolution. Developing an eco-friendly delay display system offers a powerful tool for fusing old and instant events, which can be used for visualizing motion trails. Herein, we brighten triplet excitons of carbon nanodots (CNDs) and increase their emission yield by a multidimensional confinement strategy, and the CND-based delay display array is demonstrated. The intense confinement effects via multidimensional confinement strategy suppress nonradiative transitions, and 240% enhancement in the phosphorescence efficiency and 260% enhancement in the lifetime of the CNDs are thus realized. Considering their distinctive phosphorescence performances, a delay display array containing a 4 × 4 CND-based delay lighting device is demonstrated, which can provide ultralong phosphorescence over 7 s, and the motion that occurred in different timelines is recorded clearly. This finding will motivate the investigation of phosphorescent CNDs in motion trail recognition.

The Application Effect of Evidence-Based Targeted Nursing in Severe Preeclamptic Women and Its Impact on Maternal Psychological Status, Quality of Life, and Maternal-Infant Outcomes.

Objective: To analyze the application effect of evidence-based targeted nursing in severe preeclamptic women and its impact on maternal psychological status, quality of life, and maternal-infant outcomes. Methods: A retrospective analysis was conducted on clinical data of 97 severe preeclamptic patients admitted to our hospital from June 2021 to June 2023. All patients met the complete inclusion and exclusion criteria. Based on the different nursing intervention plans received by the patients, they were divided into a control group (n=47) and an observation group (n=50). Patients in the control group received routine nursing intervention, while patients in the observation group received evidence-based targeted nursing. A comparison was made between the two groups in terms of levels of psychological status indicators, quality of life, maternal pregnancy outcomes, neonatal outcomes, Apgar scores, and nursing satisfaction. Results: (1) Psychological status indicators: Before the intervention, the two groups had no significant difference in EPDS scores and SAS scores (P > .05). After the intervention, the EPDS scores and SAS scores in the observation group were significantly lower than those in the control group (P < .05, effect size d = 0.65 for EPDS scores and d = 0.72 for SAS scores), indicating a substantial reduction in depression and anxiety levels. (2) Quality of life: Before the intervention, there was no significant difference in the scores for health status, physiological function, and mental status between the two groups (P > .05). After the intervention, the scores for health status, physiological function, and mental status in the observation group were significantly higher than in the control group (P < .05, effect size d = 0.58 for health status, d = 0.63 for physiological function, and d = 0.61 for mental status), suggesting a notable improvement in the overall quality of life for patients. (3) Maternal pregnancy outcomes: The incidence of adverse pregnancy outcomes in the control group was 42.55%, while in the observation group, it was 18.00%. The incidence of adverse pregnancy outcomes in the observation group was significantly lower than in the control group (P < .05, effect size d = 0.82), indicating a substantial reduction in adverse outcomes. (4) Neonatal outcomes and Apgar scores: The incidence of adverse neonatal outcomes in the control group was 46.81%, with an Apgar score of (7.13±1.05), while in the observation group, it was 22.00%, with an Apgar score of (7.96±1.17). The incidence of adverse neonatal outcomes in the observation group was significantly lower, and the Apgar scores were significantly higher than those in the control group (P < .05, effect size d = 0.73 for adverse neonatal outcomes, and d = 0.68 for Apgar scores), indicating improved neonatal outcomes. (5) Nursing satisfaction: The nursing satisfaction in the control group was 80.85%, whereas in the observation group, it was 96.00%. The nursing satisfaction in the observation group was significantly higher than that in the control group (P < .05, effect size d = 0.86), reflecting a higher level of satisfaction with the evidence-based targeted nursing intervention. Conclusion: Evidence-based targeted nursing intervention in severe preeclamptic women demonstrates significant benefits in improving maternal psychological well-being, quality of life, and maternal-infant outcomes. The intervention effectively reduces depression and anxiety levels, enhances overall quality of life, and reduces the incidence of adverse pregnancy and neonatal outcomes. The use of personalized care plans and enhanced patient education may contribute to these positive outcomes. Furthermore, evidence-based targeted nursing intervention promotes higher levels of nursing satisfaction and fosters better doctor-patient relationships. These findings highlight the importance of implementing evidence-based targeted nursing as a standard approach in the management of severe preeclampsia, ultimately improving the holistic care and well-being of both mothers and infants.

Impact of Type 2 Diabetes Mellitus on Left Atrioventricular Coupling and Left Atrial Deformation in Patients with Essential Hypertension: An MRI Feature Tracking Study.

BACKGROUND: Hypertension (HTN) and type 2 diabetes mellitus (T2DM) are both associated with left ventricular (LV) and left atrial (LA) structural and functional abnormalities; however, the relationship between the left atrium and ventricle in this population is unclear. PURPOSE: To identify differences between hypertensive patients with and without T2DM as the basis for further investigation the atrioventricular coupling relationship. STUDY TYPE: Cross-sectional, retrospective study. POPULATION: 89 hypertensive patients without T2DM [HTN (T2DM-)] (age: 58.4 +/- 11.9 years, 48 male), 62 hypertensive patients with T2DM [HTN (T2DM+)] (age: 58.5 +/- 9.1 years, 32 male) and 70 matched controls (age: 55.0 +/- 9.6 years, 37 male). FIELD STRENGTH/SEQUENCE: 2D balanced steady-state free precession cine sequence at 3.0 T. ASSESSMENT: LA reservoir, conduit, and booster strain (εs, εe, and εa) and strain rate (SRs, SRe, and SRa), LV radial, circumferential and longitudinal peak strain (PS) and peak systolic strain rate and peak diastolic strain rate (PSSR and PDSR) were derived from LA and LV cine images and compared between groups. STATISTICAL TESTS: Chi-square or Fisher's exact test, one-way analysis of variance, analysis of covariance, Pearson's correlation, multivariable linear regression analysis, and intraclass correlation coefficient. A P value <0.05 was considered significant. RESULTS: Compared with controls, εs, εe, SRe and PS-longitudinal, PDSR-radial, and PDSR-longitudinal were significantly lower in HTN (T2DM-) group, and they were even lower in HTN (T2DM+) group than in both controls and HTN (T2DM-) group. SRs, εa, SRa, as well as PS-radial, PS-circumferential, PSSR-radial, and PSSR-circumferential were significantly lower in HTN (T2DM+) compared with controls. Multivariable regression analyses demonstrated that: T2DM and PS-circumferential and PS-longitudinal (ß = -4.026, -0.486, and -0.670, respectively) were significantly associated with εs; T2DM and PDSR-radial and PDSR-circumferential were significantly associated with εe (ß = -3.406, -3.352, and -6.290, respectively); T2DM and PDSR-radial were significantly associated with SRe (ß = 0.371 and 0.270, respectively); T2DM and PDSR-longitudinal were significantly associated with εa (ß = -1.831 and 5.215, respectively); and PDSR-longitudinal was significantly associated with SRa (ß = 1.07). DATA CONCLUSION: In hypertensive patients, there was severer LA dysfunction in those with coexisting T2DM, which may be associated with more severe LV dysfunction and suggests adverse atrioventricular coupling. EVIDENCE LEVEL: 3. TECHNICAL EFFICACY: Stage 3.

Improving the Prognostic Evaluation Precision of Hospital Outcomes for Heart Failure Using Admission Notes and Clinical Tabular Data: Multimodal Deep Learning Model.

BACKGROUND: Clinical notes contain contextualized information beyond structured data related to patients' past and current health status. OBJECTIVE: This study aimed to design a multimodal deep learning approach to improve the evaluation precision of hospital outcomes for heart failure (HF) using admission clinical notes and easily collected tabular data. METHODS: Data for the development and validation of the multimodal model were retrospectively derived from 3 open-access US databases, including the Medical Information Mart for Intensive Care III v1.4 (MIMIC-III) and MIMIC-IV v1.0, collected from a teaching hospital from 2001 to 2019, and the eICU Collaborative Research Database v1.2, collected from 208 hospitals from 2014 to 2015. The study cohorts consisted of all patients with critical HF. The clinical notes, including chief complaint, history of present illness, physical examination, medical history, and admission medication, as well as clinical variables recorded in electronic health records, were analyzed. We developed a deep learning mortality prediction model for in-hospital patients, which underwent complete internal, prospective, and external evaluation. The Integrated Gradients and SHapley Additive exPlanations (SHAP) methods were used to analyze the importance of risk factors. RESULTS: The study included 9989 (16.4%) patients in the development set, 2497 (14.1%) patients in the internal validation set, 1896 (18.3%) in the prospective validation set, and 7432 (15%) patients in the external validation set. The area under the receiver operating characteristic curve of the models was 0.838 (95% CI 0.827-0.851), 0.849 (95% CI 0.841-0.856), and 0.767 (95% CI 0.762-0.772), for the internal, prospective, and external validation sets, respectively. The area under the receiver operating characteristic curve of the multimodal model outperformed that of the unimodal models in all test sets, and tabular data contributed to higher discrimination. The medical history and physical examination were more useful than other factors in early assessments. CONCLUSIONS: The multimodal deep learning model for combining admission notes and clinical tabular data showed promising efficacy as a potentially novel method in evaluating the risk of mortality in patients with HF, providing more accurate and timely decision support.

Pharmacological mechanism of natural antidepressants: The role of mitochondrial quality control.

BACKGROUND: Depression is a mental illness characterized by persistent sadness and a reduced capacity for pleasure. In clinical practice, SSRIs and other medications are commonly used for therapy, despite their various side effects. Natural products present distinct advantages, including synergistic interactions among multiple components and targeting multiple pathways, suggesting their tremendous potential in depression treatment. Imbalance in mitochondrial quality control (MQC) plays a significant role in the pathology of depression, emphasizing the importance of regulating MQC as a potential intervention strategy in addressing the onset and progression of depression. However, the role and mechanism through which natural products regulate MQC in depression treatments still need to be comprehensively elucidated, particularly in clinical and preclinical settings. PURPOSE: This review was aimed to summarize the findings of recent studies and outline the pharmacological mechanisms by which natural products modulate MQC to exert antidepressant effects. Additionally, it evaluated current research limitations and proposed new strategies for future preclinical and clinical applications in the depression domain. METHODS: To study the main pharmacological mechanisms underlying the regulation of MQC by natural products in the treatment of depression, we conducted a thorough search across databases such as PubMed, Web of Science, and ScienceDirect databases to classify and summarize the relationship between MQC and depression, as well as the regulatory mechanisms of natural products. RESULTS: Numerous studies have shown that irregularities in the MQC system play an important role in the pathology of depression, and the regulation of the MQC system is involved in antidepressant treatments. Natural products mainly regulate the MQC system to induce antidepressant effects by alleviating oxidative stress, balancing ATP levels, promoting mitophagy, maintaining calcium homeostasis, optimizing mitochondrial dynamics, regulating mitochondrial membrane potential, and enhancing mitochondrial biogenesis. CONCLUSIONS: We comprehensively summarized the regulation of natural products on the MQC system in antidepressants, providing a unique perspective for the application of natural products within antidepressant therapy. However, extensive efforts are imperative in clinical and preclinical investigations to delve deeper into the mechanisms underlying how antidepressant medications impact MQC, which is crucial for the development of effective antidepressant treatments.

PM2.5 exposure contributes to anxiety and depression-like behaviors via phenyl-containing compounds interfering with dopamine receptor.

As a global problem, fine particulate matter (PM2.5) really needs local fixes. Considering the increasing epidemiological relevance to anxiety and depression but inconsistent toxicological results, the most important question is to clarify whether and how PM2.5 causally contributes to these mental disorders and which components are the most dangerous for crucial mitigation in a particular place. In the present study, we chronically subjected male mice to a real-world PM2.5 exposure system throughout the winter heating period in a coal combustion area and revealed that PM2.5 caused anxiety and depression-like behaviors in adults such as restricted activity, diminished exploratory interest, enhanced repetitive stereotypy, and elevated acquired immobility, through behavioral tests including open field, elevated plus maze, marble-burying, and forced swimming tests. Importantly, we found that dopamine signaling was perturbed using mRNA transcriptional profile and bioinformatics analysis, with Drd1 as a potential target. Subsequently, we developed the Drd1 expression-directed multifraction isolating and nontarget identifying framework and identified a total of 209 compounds in PM2.5 organic extracts capable of reducing Drd1 expression. Furthermore, by applying hierarchical characteristic fragment analysis and molecular docking and dynamics simulation, we clarified that phenyl-containing compounds competitively bound to DRD1 and interfered with dopamine signaling, thereby contributing to mental disorders. Taken together, this work provides experimental evidence for researchers and clinicians to identify hazardous factors in PM2.5 and prevent adverse health outcomes and for local governments and municipalities to control source emissions for diminishing specific disease burdens.

Neurotoxicity of Combined Exposure to the Heavy Metals (Pb and As) in Zebrafish (Danio rerio).

Lead (Pb) and arsenic (As) are commonly occurring heavy metals in the environment and produce detrimental impacts on the central nervous system. Although they have both been indicated to exhibit neurotoxic properties, it is not known if they have joint effects, and their mechanisms of action are likewise unknown. In this study, zebrafish were exposed to different concentrations of Pb (40 µg/L, 4 mg/L), As (32 µg/L, 3.2 mg/L) and their combinations (40 µg/L + 32 µg/L, 4 mg/L + 3.2 mg/L) for 30 days. The histopathological analyses showed significant brain damage characterized by glial scar formation and ventricular enlargement in all exposed groups. In addition, either Pb or As staining inhibited the swimming speed of zebrafish, which was enhanced by their high concentrations in a mixture. To elucidate the underlying mechanisms, we examined changes in acetylcholinesterase (AChE) activity, neurotransmitter (dopamine, 5-hydroxytryptamine) levels, HPI axis-related hormone (cortisol and epinephrine) contents and neurodevelopment-related gene expression in zebrafish brain. The observations suggest that combined exposure to Pb and As can cause abnormalities in swimming behavior and ultimately exacerbate neurotoxicity in zebrafish by interfering with the cholinergic system, dopamine and 5-hydroxytryptamine signaling, HPI axis function as well as neuronal development. This study provides an important theoretical basis for the mixed exposure of heavy metals and their toxicity to aquatic organisms.

Retraction: Salidroside inhibits the proliferation and migration of gastric carcinoma cells and tumor growth via the activation of ERS-dependent autophagy and apoptosis.

[This retracts the article DOI: 10.1039/C9RA00044E.].

The rapidly evolving X-linked MIR-506 family fine-tunes spermatogenesis to enhance sperm competition.

Despite rapid evolution across eutherian mammals, the X-linked MIR-506 family miRNAs are located in a region flanked by two highly conserved protein-coding genes (SLITRK2 and FMR1) on the X chromosome. Intriguingly, these miRNAs are predominantly expressed in the testis, suggesting a potential role in spermatogenesis and male fertility. Here, we report that the X-linked MIR-506 family miRNAs were derived from the MER91C DNA transposons. Selective inactivation of individual miRNAs or clusters caused no discernible defects, but simultaneous ablation of five clusters containing 19 members of the MIR-506 family led to reduced male fertility in mice. Despite normal sperm counts, motility, and morphology, the KO sperm were less competitive than wild-type sperm when subjected to a polyandrous mating scheme. Transcriptomic and bioinformatic analyses revealed that these X-linked MIR-506 family miRNAs, in addition to targeting a set of conserved genes, have more targets that are critical for spermatogenesis and embryonic development during evolution. Our data suggest that the MIR-506 family miRNAs function to enhance sperm competitiveness and reproductive fitness of the male by finetuning gene expression during spermatogenesis.

Over-the-scope clip as a rescue treatment for massive bleeding due to Dieulafoy lesion at the colorectal anastomosis: A case report.

RATIONALE: The bleeding of Dieulafoy lesion predominantly involves the proximal stomach and leads to severe gastrointestinal bleeding. However, these lesions have also been reported in the whole gastrointestinal tract. Bleeding of Dieulafoy lesions at the anastomosis was seldomly reported and was very easy to be ignored clinically. PATIENT CONCERNS: We describe a 72-year-old woman with a past history of surgery for rectal carcinoma hospitalized with chief complaint of massive rectal bleeding. No gross bleeding lesion was found during the first emergency colonoscopy. Despite multiple blood transfusions, her hemoglobin rapidly dropped to 5.8 g/dL. DIAGNOSIS: She was diagnosed with Dieulafoy lesion at the colorectal anastomosis during the second emergency colonoscopy. INTERVENTIONS: Primary hemostasis was achieved by endoscopic hemostatic clipping. However, she experienced another large volume hematochezia 3 days later, and then received another endoscopic hemostatic clipping. She was improved and discharged. However, this patient underwent hematochezia again 1 month later. Bleeding was arrested successfully after the over-the-scope clip (OTSC) was placed during the fourth emergency colonoscopy. OUTCOMES: This patient underwent 4 endoscopic examinations and treatments during 2 hospitalizations. The lesion was overlooked during the first emergency colonoscopy. The second and third endoscopes revealed Dieulafoy lesion at the colorectal anastomosis and performed endoscopic hemostatic clippings, but delayed rebleeding occurred. The bleeding was stopped after the fourth emergency colonoscopy using OTSC. There was no further rebleeding during hospitalization and after 2-year of follow-up. LESSONS: As far as we know, there is no reported case of lower gastrointestinal bleeding caused by Dieulafoy lesion at the colorectal anastomosis, OTSC is a safe and effective rescue treatment for Dieulafoy lesions.