Giant chiral magnetoelectric oscillations in a van der Waals multiferroic.

Helical spin structures are expressions of magnetically induced chirality, entangling the dipolar and magnetic orders in materials1-4. The recent discovery of helical van der Waals multiferroics down to the ultrathin limit raises prospects of large chiral magnetoelectric correlations in two dimensions5,6. However, the exact nature and magnitude of these couplings have remained unknown so far. Here we perform a precision measurement of the dynamical magnetoelectric coupling for an enantiopure domain in an exfoliated van der Waals multiferroic. We evaluate this interaction in resonance with a collective electromagnon mode, capturing the impact of its oscillations on the dipolar and magnetic orders of the material with a suite of ultrafast optical probes. Our data show a giant natural optical activity at terahertz frequencies, characterized by quadrature modulations between the electric polarization and magnetization components. First-principles calculations further show that these chiral couplings originate from the synergy between the non-collinear spin texture and relativistic spin-orbit interactions, resulting in substantial enhancements over lattice-mediated effects. Our findings highlight the potential for intertwined orders to enable unique functionalities in the two-dimensional limit and pave the way for the development of van der Waals magnetoelectric devices operating at terahertz speeds.

Electrostatic moiré potential from twisted hexagonal boron nitride layers.

Moiré superlattices host a rich variety of correlated electronic phases. However, the moiré potential is fixed by interlayer coupling, and it is dependent on the nature of carriers and valleys. In contrast, it has been predicted that twisted hexagonal boron nitride (hBN) layers can impose a periodic electrostatic potential capable of engineering the properties of adjacent functional layers. Here, we show that this potential is described by a theory of electric polarization originating from the interfacial charge redistribution, validated by its dependence on supercell sizes and distance from the twisted interfaces. This enables controllability of the potential depth and profile by controlling the twist angles between the two interfaces. Employing this approach, we further demonstrate how the electrostatic potential from a twisted hBN substrate impedes exciton diffusion in semiconductor monolayers, suggesting opportunities for engineering the properties of adjacent functional layers using the surface potential of a twisted hBN substrate.

Fermi Pressure and Coulomb Repulsion Driven Rapid Hot Plasma Expansion in a van der Waals Heterostructure.

Transition metal dichalcogenide heterostructures provide a versatile platform to explore electronic and excitonic phases. As the excitation density exceeds the critical Mott density, interlayer excitons are ionized into an electron-hole plasma phase. The transport of the highly non-equilibrium plasma is relevant for high-power optoelectronic devices but has not been carefully investigated previously. Here, we employ spatially resolved pump-probe microscopy to investigate the spatial-temporal dynamics of interlayer excitons and hot-plasma phase in a MoSe2/WSe2 twisted bilayer. At the excitation density of ∼1014 cm-2, well exceeding the Mott density, we find a surprisingly rapid initial expansion of hot plasma to a few microns away from the excitation source within ∼0.2 ps. Microscopic theory reveals that this rapid expansion is mainly driven by Fermi pressure and Coulomb repulsion, while the hot carrier effect has only a minor effect in the plasma phase.

Twist Angle-Dependent Interlayer Exciton Lifetimes in van der Waals Heterostructures.

In van der Waals (vdW) heterostructures formed by stacking two monolayers of transition metal dichalcogenides, multiple exciton resonances with highly tunable properties are formed and subject to both vertical and lateral confinement. We investigate how a unique control knob, the twist angle between the two monolayers, can be used to control the exciton dynamics. We observe that the interlayer exciton lifetimes in MoSe_{2}/WSe_{2} twisted bilayers (TBLs) change by one order of magnitude when the twist angle is varied from 1° to 3.5°. Using a low-energy continuum model, we theoretically separate two leading mechanisms that influence interlayer exciton radiative lifetimes. The shift to indirect transitions in the momentum space with an increasing twist angle and the energy modulation from the moiré potential both have a significant impact on interlayer exciton lifetimes. We further predict distinct temperature dependence of interlayer exciton lifetimes in TBLs with different twist angles, which is partially validated by experiments. While many recent studies have highlighted how the twist angle in a vdW TBL can be used to engineer the ground states and quantum phases due to many-body interaction, our studies explore its role in controlling the dynamics of optically excited states, thus, expanding the conceptual applications of "twistronics".

Controlling the Magnetic Anisotropy of the van der Waals Ferromagnet Fe3GeTe2 through Hole Doping.

Identifying material parameters affecting properties of ferromagnets is key to optimized materials that are better suited for spintronics. Magnetic anisotropy is of particular importance in van der Waals magnets, since it not only influences magnetic and spin transport properties, but also is essential to stabilizing magnetic order in the two-dimensional limit. Here, we report that hole doping effectively modulates the magnetic anisotropy of a van der Waals ferromagnet and explore the physical origin of this effect. Fe3-xGeTe2 nanoflakes show a significant suppression of the magnetic anisotropy with hole doping. Electronic structure measurements and calculations reveal that the chemical potential shift associated with hole doping is responsible for the reduced magnetic anisotropy by decreasing the energy gain from the spin-orbit induced band splitting. Our findings provide an understanding of the intricate connection between electronic structures and magnetic properties in two-dimensional magnets and propose a method to engineer magnetic properties through doping.

α-Linolenic Acid-Enriched Cold-Pressed Perilla Oil Suppress High-Fat Diet-Induced Hepatic Steatosis through Amelioration of the ER Stress-Mediated Autophagy.

Perilla oil has been considered to have excellent potential for treating various diseases due to its contents of beneficial fatty acids, such as α-linolenic acid, oleic acid and linoleic acid. The therapeutic effects and molecular mechanism of an α-linolenic acid-enriched cold-pressed perilla oil (LEP) on hepatic steatosis of an obesity model were investigated by analyzing alterations in fat accumulation and endoplasmic reticulum (ER) stress-mediated autophagy, in high-fat diet (HFD)-induced obesity C57BL/6N mice treated with LEP for 16 weeks. Although no significant alterations were detected in body weight and most organ weights, the liver weight and accumulation of lipid droplets in the liver section were significantly lower in HFD + LEP treated group as compared to the HFD + Vehicle treated group. Reduced mRNA expression levels of adipogenesis and lipogenesis regulating factors, including the peroxisome proliferator-activated receptor (PPAR)γ, CCAAT/enhancer-binding protein (C/EBP)α, fatty acid synthase (FAS), and adipocyte fatty acid-binding protein 2 (aP2) were observed after LEP treatment for 16 weeks, while the levels of lipolysis were remarkably increased in the same group. Moreover, the LEP-treated groups showed suppression of ER stress-regulating factors, such as the C/EBP homologous protein (CHOP), eukaryotic translation initiation factor 2α (eIF2α), inositol-requiring protein 1 (IRE1)α, and Jun-N-terminal kinase (JNK) during anti-hepatic steatosis effects. The expression level of the microtubule-associated protein 1A/1B-light chain 3 (LC3) protein and phosphatidylinositol-3-kinase (PI3K)/AKT/ mammalian target of rapamycin (mTOR) pathway for the autophagy response showed a significant decrease in the HFD+LEP-treated group. Furthermore, ER stress-mediated autophagy was accompanied with enhanced phosphorylation of extracellular signal-regulated kinase (ERK), JNK, and p38 protein in the mitogen-activated protein (MAP) kinase signaling pathway. Taken together, the results of the present study indicate that treatment with LEP inhibits hepatic steatosis in the HFD-induced obese model through regulation of adipogenesis and lipolysis. We believe our results are the first to show that the anti-hepatic steatosis activity of α-linolenic acid from cold-pressed perilla oil might be tightly correlated with the amelioration of ER stress-mediated autophagy.

Asparagus cochinchinensis stimulates release of nerve growth factor and abrogates oxidative stress in the Tg2576 model for Alzheimer's disease.

BACKGROUD: Use of multifunctional drugs with neurotrophic supporting and oxidative stress suppressing activity may be considered a therapeutic strategy to protect or repair cellular damage caused during the progression of Alzheimer's disease (AD). In this study, we investigated the therapeutic effects of aqueous extract of A. cochinchinesis root (AEAC), particularly its role as a nerve growth factor (NGF) stimulator and anti-oxidant in Tg2576 mice showing AD phenotypes of human. METHODS: Tg2576 mice were received 100 mg/kg/day AEAC via oral administration, while mice in the Vehicle treated group received dH2O for 4 weeks. Non-Tg littermates were used as a control group. Following AEAC treatment for 4 weeks, NGF function, anti-oxidantive status, Aß-42 peptide level, γ-secretase expression and neuronal cell functions were analyzed in the brain of Tg2576 mice. RESULTS: AEAC containing flavonoids, phenols, saponins and protodioscin induced enhancement of NGF secretion and decreased intracellular ROS in the neuronal and microglial cell line. These effects as well as enhanced SOD levels were also detected in AEAC treated Tg2576 mice. The expression of p-Akt among downstream effectors of the high affinity NGF receptor was dramatically recovered in AEAC treated Tg2576 mice, while the expression of p75NTR was slightly recovered in the same group. Significant recovery on the level of Aß-42 peptides and the expression of γ-secretase members including PS-2, APH-1 and NCT were detected in AEAC treated Tg2576 mice. Furthermore, AEAC treated Tg2576 mice showed decreased numbers of dead cells and suppressed acetyl choline esterase (AChE) activity. CONCLUSIONS: These results suggest that AEAC contribute to improving the deposition of Aß-42 peptides and neuronal cell injuries during the pathological progression stage of AD in the brain of Tg2576 mice through increased NGF secretion and suppressed oxidative stress.

Diosgenin effectively suppresses skin inflammation induced by phthalic anhydride in IL-4/Luc/CNS-1 transgenic mice.

To quantitatively evaluate the therapeutic effects of diosgenin (DG) and investigate the role of IL-4 on skin inflammation, alterations in luciferase-derived signal and general phenotype biomarkers were measured in IL-4/Luc/CNS-1 transgenic mice with phthalic anhydride (PA)-induced skin inflammation after treatment with DG for 4 weeks. High levels of luciferase-derived signal detected in the abdominal region and submandibular lymph node (SL) of the PA treated group was significantly decreased by 67-88% in the PA + DG cotreated group. Furthermore, the weight of the lymph node and spleen, IgE concentration, epidermis thickness, and number of infiltrated mast cells were lower in the PA + DG treated group than the PA + Vehicle treated group. Moreover, expression of IL-6 and vascular endothelial growth factor (VEGF) also decreased in the PA + DG cotreated group. These results suggest that PA-induced skin inflammation could be successfully suppressed by DG treatment in IL-4/Luc/CNS-1 Tg mice through attenuation of IL-4 and IL-6 expression, as well as decreased IgE concentration and mast cells infiltration.

Changes in arterial blood gases after use of high-flow nasal cannula therapy in the ED.

INTRODUCTION: A high-flow nasal cannula (HFNC) has been used to treat patients with dyspnea. We identified changes in arterial blood gas (ABG) of patients visiting the emergency department (ED) with hypercapnic and nonhypercapnic respiratory failure after use of an HFNC. METHODS: This study was a retrospective chart review of patients with respiratory failure who visited the hospital and used an HFNC in the ED. The study period was July 1, 2011, to December 31, 2013. Patients with Paco2 greater than 45 mm Hg before the HFNC ABG analyses were included in the hypercapnia group; others comprised the nonhypercapnia group. Primary outcomes were the changes in ABG before and after use of an HFNC in the hypercapnia and nonhypercapnia groups. Progression to noninvasive or invasive ventilation and mortality rates were also assessed. RESULTS: A total of 173 patients were included after exclusion of 92 according to exclusion criteria. Eighty-one patients (hypercapnia group, 46, and nonhypercapnia group, 35) were included. Paco2 significantly decreased among all patients after use of HFNC (from 54.7±26.4 mm Hg to 51.3±25.8 mm Hg; P=.02), but the reduction was significant only in the hypercapnia group (from 73.2±20.0 to 67.2±23.4; P=.02). Progression to noninvasive or invasive ventilation and mortality rates were similar between the groups. CONCLUSIONS: Use of an HFNC in patients with hypercapnia could show a significant trend of decrease in Paco2. Progression to noninvasive or invasive ventilation and mortality rates were similar in patients with and without hypercapnia.

Simultaneous event of brachial artery occlusion and acute embolic stroke.

Although the rapid and accurate diagnosis of both acute ischemic stroke and extremity ischemia is essential to the timely and appropriate treatment, it is not always easy to differentiate between true stroke and stroke mimics. Although in general, limb ischemia due to extremity embolism is not included in stroke mimics or misdiagnosis, limb arterial embolism should be considered in thedifferential diagnosis of acute monoparesis because the diagnosis maybe missed if the other typical manifestations of this presentation(pain, pallor, pulselessness, sensory loss, and coolness of the arm) are overlooked. Therefore, it is important to ensure that important signsare not missed whether the evaluation of the patient is done at thebedside. We report a case of a male patient presented to an emergency department with acute right upper extremity pain with headache, gait disturbance, and confused mentality. He was diagnosed by simultaneou sbrachial artery occlusion and acute stroke, which resulted in emergency surgical embolectomy and anticoagulation therapy.

The uniform chest compression depth of 50 mm or greater recommended by current guidelines is not appropriate for all adults.

OBJECTIVE: This study was conducted to evaluate the appropriateness of the chest compression (CC) depth recommended in the current guidelines and simulated external CCs, and to characterize the optimal CC depth for an adult by body mass index (BMI). METHODS: Adult patients who underwent chest computed tomography as a screening test for latent pulmonary diseases in the health care center were enrolled in this study. We calculated the internal anteroposterior (AP) diameter (IAPD) and external AP diameter (EAPD) of the chest across BMIs (<18.50, 18.50-24.99, 25.00-29.99, and ≥30.00 kg/m(2)) for simulated CC depth. We also calculated the residual chest depths less than 20 mm for simulated CC depth. RESULTS: There was a statistically significant difference in the chest EAPD and IAPD measured at the lower half of the sternum for each BMI groups (EAPD: R(2) = 0.638, P < .001; IAPD: R(2) = 0.297, P < .001). For one-half external AP CC, 100% of the patients, regardless of BMI, had a calculated residual internal chest depth less than 20 mm. For one-fourth external AP CC, no patients had a calculated residual internal chest depth less than 20 mm. For one-third external AP CC, only 6.48% of the patients had a calculated residual internal chest depth less than 20 mm. CONCLUSIONS: It is not appropriate that the current CC depth (≥50 mm), expressed only as absolute measurement without a fraction of the depth of the chest, is applied uniformly in all adults. In addition, in terms of safety and efficacy, simulated CC targeting approximately between one-third and one-fourth EAPD CC depth might be appropriate.

The Comparison of Accidental Poisonings Between Pharmaceuticals and Nonpharmaceuticals in Children Younger than 3 Years.

INTRODUCTION: The management of pediatric poisoning is dependent on the type of toxicant ingested; however, little information has been published regarding the difference in poisoning by pharmaceuticals and nonpharmaceuticals in children. We compared the accidental poisoning of children younger than 3 years who had ingested pharmaceuticals or nonpharmaceuticals using emergency medical information center data. METHODS: We retrospectively reviewed the records of the poisonings of children younger than 3 years who were evaluated by the Seoul Emergency Medical Information Center in 2011. The demographic data and detailed information regarding the poisonings were investigated. The substances that caused the poisonings were divided into the following 2 groups: pharmaceuticals and nonpharmaceuticals, and their characteristics and the differences between the 2 types of poisonings were investigated. RESULTS: A total of 1279 cases were collected, most of which involved children who were 13 to 24 months old. Boys (51.3%) were involved more than girls. Exposure to nonpharmaceuticals (60.7%) was more common than exposure to pharmaceuticals. Personal care products and respiratory agents were the most commonly implicated substances. There were several significant differences between the pharmaceutical and nonpharmaceutical groups. Poisoning by pharmaceuticals occurred more frequently in older children and more frequently at night. Although the exact exposure of the children in the pharmaceutical group was known and they required more treatment in the emergency department, they were not given extra immediate first aid than the children in the nonpharmaceutical group. CONCLUSIONS: Because there were several significant differences in the characteristics of accidental pediatric poisonings between the pharmaceutical and nonpharmaceutical groups, preventive strategies and educational programs should be implemented on the basis of the causative agent.

Atraumatic splenic rupture after coagulopathy owing to a snakebite.

Among the many complications that may follow envenomation by some species of venomous snakes, coagulopathy is common and well known. However, hemoperitoneum induced by coagulopathy after a snakebite is rare. Atraumatic spontaneous splenic rupture is also an uncommon and life-threatening condition. Here, we report a case of presumptive envenomation by Gloydius spp. that resulted in atraumatic splenic rupture as a probable manifestation of coagulopathy, which has not been previously reported.

Evaluation of COVID-19 vaccine effectiveness in different high-risk facility types during a period of Delta variant dominance in the Republic of Korea: a cross-sectional study.

BACKGROUND: We evaluated the effectiveness of coronavirus disease 2019 vaccination in high-risk facilities in the Republic of Korea during the period when the highly transmissible Delta variant was prevalent. Additionally, we aimed to explore any disparities in vaccine effectiveness (VE) across various types of institutions, specifically distinguishing between non-medical and medical establishments. METHODS: We examined 8 outbreak clusters covering 243 cases and 895 contacts from 8 high-risk facilities divided into 2 groups: group A (4 non-medical institutions) and group B (4 medical institutions). These clusters were observed from July 27, 2021 to October 16, 2021 for the attack rate (AR) and VE with respect to disease severity. A generalized linear model with a binomial distribution was used to determine the odds ratio (OR) for disease severity and death. RESULTS: AR was notably lower in group B (medical institutions). Furthermore, VE analysis revealed that group A exhibited higher effectivity for disease severity and death than group B. The OR for disease severity was 0.24 (95% confidence interval [CI], 0.03-2.16) for group A and 0.27 (95% CI, 0.12-0.64) for group B, with the OR for death at 0.12 (95% CI, 0.01-1.32) in group A and 0.34 (95% CI, 0.14-0.87) in group B. CONCLUSION: Although VE may vary across institutions, our findings underscore the importance of implementing vaccinations in high-risk facilities. Customized vaccination programs, tailored response plans, and competent management personnel are essential for effectively addressing and mitigating public health challenges.

Anisotropic Excitons Reveal Local Spin Chain Directions in a van der Waals Antiferromagnet.

A long-standing pursuit in materials science is to identify suitable magnetic semiconductors for integrated information storage, processing, and transfer. Van der Waals magnets have brought forth new material candidates for this purpose. Recently, sharp exciton resonances in antiferromagnet NiPS3 have been reported to correlate with magnetic order, that is, the exciton photoluminescence intensity diminishes above the Néel temperature. Here, it is found that the polarization of maximal exciton emission rotates locally, revealing three possible spin chain directions. This discovery establishes a new understanding of the antiferromagnet order hidden in previous neutron scattering and optical experiments. Furthermore, defect-bound states are suggested as an alternative exciton formation mechanism that has yet to be explored in NiPS3 . The supporting evidence includes chemical analysis, excitation power, and thickness dependent photoluminescence and first-principles calculations. This mechanism for exciton formation is also consistent with the presence of strong phonon side bands. This study shows that anisotropic exciton photoluminescence can be used to read out local spin chain directions in antiferromagnets and realize multi-functional devices via spin-photon transduction.

A Comparative Study of Urinary Tests and Cultures for the Effectiveness of Fosfomycin in Catheter-Related Urinary Tract Infections.

As the elderly population increases due to an aging society, the number of patients with catheters is increasing, and treatment for urinary infections is needed. The current study analyzed the effectiveness of fosfomycin, the primary antibiotic used to treat urinary tract infections (UTIs), in these patients. Patients who received fosfomycin as the primary antibiotic for a UTI were selected, and the results of urine tests and cultures before and after fosfomycin administration were compared and analyzed. The degree of UTI in patients with a catheter was found to be more severe (p = 0.020), and the infecting strains were found to be different depending on whether a catheter was present (p = 0.014). There was a difference in the treatment success rate depending on whether or not a catheter was present (53.6% vs. 70.4%), but it was found that the treatment rate was more than 50% regardless of whether a catheter was present. The bacterial type, as well as the treatment rate based on the bacterium, differed depending on the presence of a catheter. Fosfomycin has a success rate of more than 50%, even in patients with catheters; therefore, it can be considered the primary antibiotic for treating UTIs.

Protective role of fermented mulberry leave extract in LPS­induced inflammation and autophagy of RAW264.7 macrophage cells.

Mulberry leaves have antioxidant activity and anti­inflammatory effects in several types of cells. However, the efficacy of mulberry leaves fermented with Cordyceps militaris remains unknown. Therefore, the present study aimed to investigate whether the ethanol extracts of mulberry leaves fermented with C. militaris (EMfC) can prevent lipopolysaccharide (LPS)­induced inflammation and autophagy in macrophages. To achieve this, RAW264.7 cells pretreated with three different dose of EMfCs were subsequently stimulated with LPS, and examined for alterations in the regulatory factors of inflammatory responses and key parameters of the autophagy signaling pathway. EMfC treatment inhibited the generation of reactive oxidative species; however, significant activity was observed for 2,2­diphenyl­1­picrylhydrazyl (DPPH) radical scavenging (IC50=579.6703 mg/ml). Most regulatory factors in inflammatory responses were significantly inhibited following treatment with EMfC, without any significant cellular toxicity. EMfC­treated groups exhibited marked suppression of nitrogen oxide (NO) levels, mRNA expression levels of iNOS/COX­2, levels of all inflammatory cytokines (TNF­α, IL­1ß and IL­6) and phosphorylation of MAPK members, as well as recovery of cell cycle progression. Furthermore, similar effects were observed in the LPS­induced autophagy signaling pathway of RAW264.7 cells. The expression levels of microtubule­associated protein 1A/1B­light chain 3 (LC3) and Beclin exhibited a dose­dependent decrease in the EMfC+LPS­treated groups compared with in the Vehicle+LPS­treated group, whereas the phosphorylation of PI3K and mTOR were enhanced in a dose­dependent manner in the same groups. Overall, the results of the present study provide evidence that exposure to EMfC protects against LPS­induced inflammation and autophagy in RAW264.7 cells. These results indicated that EMfC is a potential candidate for treatment of inflammatory diseases.

Awareness and Work-Related Factors Associated with Scrub Typhus: A Case-Control Study from South Korea.

This study aimed to examine the awareness and the work-related factors associated with scrub typhus to provide data essential for evidence-based preventive strategies. A community-based case control study was carried out in the rural areas of Gyeongsangbuk-do, South Korea. Confirmed cases of scrub typhus (n = 57) were based on laboratory tests performed by the Korean Centers for Disease Control and Prevention (KCDC), 114 matched neighborhood controls, age (±6 years), gender and area of residence in the Gyeongsangbuk-do of South Korea. These cases were contracted over the 12-month period of January to December 2015. Overall, 61.4% cases and 79.8% of the control group had heard about scrub typhus. Cases were less aware about the fact that mites are mainly found in the bushes and that long sleeves and full-length pants and boots helped prevent scrub typhus. However, more were aware of the eschar lesion as a characteristic sign of scrub typhus. Work related risk factors such as having a wetland or puddles of water surrounding the house, dry field farming and working in the livestock industry were significantly associated with the scrub typhus. Health promotion strategies, such as creating general awareness, personal protection methods and improving personal hygiene and environmental sanitation in collaboration with relevant sectors, are recommended to reduce the burden of scrub typhus. Further intervention studies on awareness and behavioral and environmental modifications are required to investigate the effectiveness of such interventions.

Isolation and structural determination of squalene synthase inhibitor from Prunus mume fruit.

Squalene synthase plays an important role in the cholesterol biosynthetic pathway. Inhibiting this enzyme in hypercholesterolemia can lower not only plasma cholesterol but also plasma triglyceride levels. A squalene synthase inhibitor was screened from Prunus mume fruit, and then purified via sequential processes of ethanol extraction, HP-20 column chromatography, ethyl acetate extraction, silica gel column chromatography, and crystallization. The squalene synthase inhibitor was identified as chlorogenic acid with a molecular mass of 354 Da and a molecular formula of C16H18O9 based on UV spectrophotometry, 1H and 13C NMRs, and mass spectrometry. Chlorogenic acid inhibited the squalene synthase of pig liver with an IC50 level of 100 nM. Since chlorogenic acid was an effective inhibitor against the squalene synthase of an animal source, it may be a potential therapeutic agent for hypercholesterolemia.

Ethyl acetate extract from Asparagus cochinchinensis exerts anti­inflammatory effects in LPS­stimulated RAW264.7 macrophage cells by regulating COX­2/iNOS, inflammatory cytokine expression, MAP kinase pathways, the cell cycle and anti-oxidant activity.

Asparagus cochinchinesis (A. cochinchinesis) is a medicine traditionally used to treat fever, cough, kidney disease, breast cancer, inflammatory disease and brain disease in northeast Asian countries. Although numerous studies of the anti­inflammatory effects of A. cochinchinesis have been conducted, the underlying mechanisms of such effects in macrophages remain to be demonstrated. To investigate the mechanism of suppressive effects on the inflammatory response in macrophages, alterations of the nitric oxide (NO) level, the cell viability, inducible nitric oxide synthase (iNOS) and cyclooxygenase­2 (COX­2) expression levels, inflammatory cytokine expression, the mitogen-activated protein kinase (MAPK) signaling pathway, cell cycle arrest and reactive oxygen species (ROS) levels were measured in lipopolysaccharide (LPS)-activated RAW264.7 cells following treatment with ethyl acetate extract from A. cochinchinesis root (EaEAC). RAW264.7 cells pretreated two different concentrations of EaEAC prior to LPS treatment exhibited no significant toxicity. The concentration of NO was significantly decreased in the EaEAC + LPS treated group compared with the vehicle + LPS treated group. A similar decrease in mRNA transcript level of COX­2, iNOS, pro-inflammatory cytokines [tumor necrosis factor­α and interleukin (IL)­1ß] and anti­inflammatory cytokines (IL­6 and IL­10) was detected in the EaEAC + LPS treated group compared with the vehicle + LPS treated group, although the decrease rate varied. Enhancement of the phosphorylation of MAPK family members following LPS treatment was partially rescued in the EaEAC pretreated group, and the cell cycle was arrested at the G2/M phase. Furthermore, the EaEAC pretreated group exhibited a reduced level of ROS generation compared with the vehicle + LPS treated group. Taken together, these results suggest that EaEAC suppresses inflammatory responses through inhibition of NO production, COX­2 expression and ROS production, as well as differential regulation of inflammatory cytokines and cell cycle in RAW264.7 cells. In addition, these results provide strong evidence to suggest that EaEAC may be considered as an important candidate for the treatment of particular inflammatory diseases.