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Lei Zhang,* Peng Sun,* Xin Liu, Ya Yang, Ruo-Nan Sun, Xu-Dong Wang Department of Emergency Medicine, Aerospace Center Hospital, Beijing, 100049, People’s Republic of China*These authors contributed equally to this workCorrespondence: Xu-Dong Wang, Department of Emergency Medicine, Aerospace Center Hospital, 15 Yuquan Road, Haidian District, Beijing, 100049, People’s Republic of China, Tel +86 01059975120, Email wxundong@126.comObjective: We aimed to analyze the clinical characteristics and prognostic factors of patients with severe hyperkalemia in the emergency department.Methods: This retrospective cohort study included adult patients diagnosed with severe hyperkalemia who sought medical care at the emergency department of Aerospace Center Hospital between January 2018 and May 2022. Clinical data, including demographics, comorbidities, laboratory findings, and outcomes, were systematically collected. Patients were categorized into survival and deceased groups based on in-hospital mortality. Comparative analysis between these groups identified significant differences, highlighting key clinically covariates. Binary logistic regression was employed to determine the primary factors influencing patient outcomes.Results: Of 90 patients diagnosed with severe hyperkalemia, 64 were in the survival group, and 26 in the deceased group. Binary logistic regression identified several significant predictors of mortality, including higher APACHE II scores (odds ratio [OR] 1.41, P = 0.02), widened QRS wave on electrocardiogram (ECG) (OR 79.39, P = 0.04), and elevated serum potassium levels (OR 1.3, P = 0.04). In contrast, emergency blood purification was associated with a reduced mortality rate (OR 0.29, P = 0.03).Conclusion: Key risk factors for mortality in patients with severe hyperkalemia include widened QRS wave on ECG, elevated APACHE II score, and high serum potassium level. Timely correction of hyperkalemia through emergency blood purification significantly improves patient outcomes.Keywords: clinical manifestation, prognosis, risk factors, severe hyperkalemia, treatment

Introduction The medical staff involved in adverse events, referred to as second victims, usually suffer second victim syndrome endangering their health. Still, there are few organizational support projects in this area in China. Objective To explore the effect of mindfulness meditation on the level and needs of organizational support, and mindfulness awareness among nurses as second victims. Methods Forty-six nurses from a comprehensive tertiary hospital in Wuhan, China were selected to participate in the study. This study was conducted using a convenience sampling method for eight weeks of mindfulness meditation intervention. The Second Victim Experience and Support Tool and Mindfulness Attention Awareness Scale were used to assessing the need for support and mindfulness awareness of nurses prior to intervention, during the fourth and eighth weeks of intervention, and at the conclusion of the intervention course. Results The difference between the scores measured before the intervention, in the fourth week, and in the eighth week of intervention showed that the need for the second victim support from work-related organizations was significant ( F = 34.513, p = .000); there was no significant difference in the scores related to the need for nonwork-related support of the second victim in the participating nurses ( F = 1.373, p = .257); the scores of the level of mindfulness awareness were (64.85 ± 11.41), (68.63 ± 11.33), and (71.20 ± 8.41), a significant difference ( F = 18.848; p = .000) was found in terms of before and after the intervention; nurses’ second victim support needs gradually shifted from evasion to confronting problems appropriately. Conclusion Mindfulness meditation intervention is applicable to the second victim population of nurses. It is an effective way to support second victim nurses and can effectively improve their level of mindfulness and awareness.

Purpose: To explore the application effect of mind mapping-assisted flipped classroom in clinical endodontics teaching., Methods: A total of 41 fifth-year undergraduates majoring in stomatology from School of Stomatology, Tongji University, finishing their clinical internship at Departments of Endodontics from October 2023 to March 2024, were randomly divided into control group (traditional teaching group, n=21) and experimental group (flipped classroom teaching group, n=20). Theoretical assessments were conducted on the day of entering the department and at the end of eight weeks in the department. Mini-CEX assessments were conducted in the third week and at the end of the eighth week (including indicators such as medical interviews, clinical examinations, humanistic care, clinical judgment, health education, clinical operations, and overall clinical capabilities). The scores of these two assessment indicators were used to evaluate the mastery extent of basic knowledge and clinical abilities of the two groups of students, and teaching satisfaction questionnaire survey was conducted. SPSS 22.0 software package was used for data analysis., Results: In terms of theoretical assessment results, there was no significant difference between the two groups in the average scores of the first assessment. The average scores of both groups were better than those of the first assessment, and the average scores of the experimental group were significantly higher than those of the control group. In terms of mini-CEX assessment results, at the first assessment, the experimental group was better than the control group in two dimensions of clinical examination and clinical judgment, but there was no significant difference between the two groups in the other five dimensions. In the second assessment, the results of the two groups in 7 dimensions were higher than those of the first assessment, and the scores of the experimental group in 5 dimensions of medical interview, clinical examination, clinical judgment, clinical operation and overall clinical ability were significantly higher than those of the control group., Conclusions: Mind mapping-assisted flipped classroom teaching can significantly improve the subjective initiative of undergraduate students during clinical internships, enhancing their mastery extent of theoretical knowledge and overall clinical capabilities, and significantly improve the teaching effect.

Hepatitis B Virus (HBV) infection is a global public health challenge that seriously endangers human health. Soft coral, as a major source of terpenoids, contains many structurally novel and highly bioactive compounds. Sixteen cembranoids (1-16), including a new one named sinupedunol B (16), were isolated from the South China Sea Soft coral Sinularia pedunculata. The structure of the sinupedunol B (16) was determined through a combination of spectroscopic analysis and X-ray single-crystal diffraction. In this study, cembranoids isolated from Sinularia pedunculata were found of anti-HBV activity for the first time. Among them, flexilarin D (6) showed significant anti-HBV activity with an IC 50 value of 5.57 μM without cytotoxicity. We then analyzed the structure-activity relationship (SAR). Furthermore, it is demonstrated that flexilarin D (6) can accelerate the formation of capsid, inhibit HBeAg, HBV core particle DNA, HBV total RNA and pregenomic RNA in a dose dependent manner. We also confirmed the anti-HBV activity of 6 in HepG2-NTCP infection system. Finally, we demonstrated the anti-HBV mechanism of these compounds by inhibiting the ENI/Xp enhancer/promoter., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)

Cembranolides are characteristic metabolites in marine soft corals, with complex structures and widespread biological activities. However, seldom has an intensive pharmacological study been done for these intriguing marine natural products. In this work, systematic chemical investigation was performed on Sinularia pedunculata by HSQC-based small molecule accurate recognition technology (SMART), resulting in the isolation and identification of 31 cembrane-type diterpenoids, including six new ones. In the bioassay, several compounds showed significant anti-inflammatory activities on the inhibition of NO production. The structure-activity relationship (SAR) was comprehensively analyzed, and two most bioactive and less toxic compounds 8 and 9 could inhibit inflammation through suppressing NF-κB and MAPK signaling pathways, and reduce the secretion of inflammatory cytokines. In a mouse model of dextran sodium sulfate (DSS)-induced acute colitis, 8 and 9 exhibited good anti-inflammatory effects and the ability to repair the colon epithelium, giving insight into the application of cembranolides as potential ulcerative colitis (UC) agents.

Background: Sodium-glucose cotransporter 2 inhibitors are believed to improve cardiac outcomes due to their osmotic diuretic potential., Objectives: The goal of this study was to test the hypothesis that vasopressin-driven urine concentration overrides the osmotic diuretic effect of glucosuria induced by dapagliflozin treatment., Methods: DAPA-Shuttle1 (Hepato-renal Regulation of Water Conservation in Heart Failure Patients With SGLT-2 Inhibitor Treatment) was a single-center, double-blind, randomized, placebo-controlled trial, in which patients with chronic heart failure NYHA functional classes I/II and reduced ejection fraction were randomly assigned to receive dapagliflozin 10 mg daily or placebo (1:1) for 4 weeks. The primary endpoint was change from baseline in urine osmolyte concentration. Secondary endpoints included changes in copeptin levels and solute free water clearance., Results: Thirty-three randomized, sodium-glucose cotransporter 2 inhibitor-naïve participants completed the study, 29 of whom (placebo: n = 14; dapagliflozin: n = 15) provided accurate 24-hour urine collections (mean age 59 ± 14 years; left ventricular ejection fraction 31% ± 9%). Dapagliflozin treatment led to an isolated increase in urine glucose excretion by 3.3 mmol/kg/d (95% CI: 2.51-4.04; P < 0.0001) within 48 hours (early) which persisted after 4 weeks (late; 2.7 mmol/kg/d [95% CI: 1.98-3.51]; P < 0.0001). Dapagliflozin treatment increased serum copeptin early (5.5 pmol/L [95% CI: 0.45-10.5]; P < 0.05) and late (7.8 pmol/L [95% CI: 2.77-12.81]; P < 0.01), leading to proportional reductions in free water clearance (early: -9.1 mL/kg/d [95% CI: -14 to -4.12; P < 0.001]; late: -11.0 mL/kg/d [95% CI: -15.94 to -6.07; P < 0.0001]) and elevated urine concentrations (late: 134 mmol/L [95% CI: 39.28-229.12]; P < 0.01). Therefore, urine volume did not significantly increase with dapagliflozin (mean difference early: 2.8 mL/kg/d [95% CI: -1.97 to 7.48; P = 0.25]; mean difference late: 0.9 mL/kg/d [95% CI: -3.83 to 5.62]; P = 0.70)., Conclusions: Physiological-adaptive water conservation eliminated the expected osmotic diuretic potential of dapagliflozin and thereby prevented a glucose-driven increase in urine volume of approximately 10 mL/kg/d · 75 kg = 750 mL/kg/d. (Hepato-renal Regulation of Water Conservation in Heart Failure Patients With SGLT-2 Inhibitor Treatment [DAPA-Shuttle1]; NCT04080518)., Competing Interests: Funding Support and Author Disclosures The DAPA-Shuttle1 study was an investigator-initiated trial funded by AstraZeneca via the externally sponsored scientific research program (ESR-18-13712; Principal Investigator: Dr Titze). The SSIS Project was realized with grant support from Duke-NUS Medical School (Duke-NUS-KBrFA/2019/0026) to Dr Titze. No funding bodies had any role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Dr Titze has received one personal speaker fee from AstraZeneca in the past 4 years. Dr Greasley has been an employee of and shareholder in AstraZeneca. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Acute lung injury (ALI) is characterised by severe pulmonary inflammation, alveolar-capillary barrier disruption, and pulmonary oedema. Therefore, establishing effective therapeutic targets for ALI prevention is crucial. The present study reports a novel function of RNF128 in regulating LPS-induced ALI. Severe lung damage and increased immune cell infiltration were detected in RNF128-deficient mice. In vitro experiments revealed that RNF128 inhibits neutrophil activation by binding to myeloperoxidase (MPO) and reducing its levels and activity. Moreover, RNF128 regulates alveolar macrophage activation and neutrophil infiltration by interacting with TLR4, targeting it for degradation, and inhibiting NF-κB activation, hence decreasing pro-inflammatory cytokines. Our results demonstrate for the first time that RNF128 is a negative regulator of MPO and TLR4 in neutrophils and alveolar macrophages, respectively. However, AAV9-mediated RNF128 overexpression alleviated lung tissue damage and reduced inflammatory cell infiltration. Thus, RNF128 is a promising therapeutic candidate for pharmacological interventions in ALI., (© 2023. The Author(s).)

A new cembranolide, namely, sinupendunculide A (1), along with eight known related compounds (2-9), was isolated from the South China Sea Soft coral Sinularia pendunculata. The structure of sinupendunculide A (1) was established by extensive spectroscopic analysis and X-ray diffraction experiments. In a bioassay, anti-colorectal cancer (CRC) activity was performed, and the results showed that several compounds exhibited cytotoxicity against RKO cells, and a preliminary structure-activity relationship was analysed. Meanwhile, the most effective compound 7 was proven to increase reactive oxygen species levels, which promoted cell apoptosis and inhibited cell proliferation., (© 2023 Wiley-VHCA AG, Zurich, Switzerland.)

Large quantities of lead/zinc (Pb/Zn) mine tailings were deposited at tailings impoundments without proper management, which have posed considerable risks to the local ecosystem and residents in mining areas worldwide. Therefore, the geochemical behaviors of potentially toxic elements (PTEs) in tailings were in-depth investigated in this study by a coupled use of batch kinetic tests, statistical analysis and mineralogical characterization. The results indicated that among these studied PTEs, Cd concentration fluctuated within a wide range of 0.83-6.91 mg/kg, and showed the highest spatial heterogeneity. The mean Cd concentrations generally increased with depth. Cd were mainly partitioned in the exchangeable and carbonate fractions. The release potential of PTEs from tailings was ranged as: Cd > Mn > Zn > Pb > As, Cd > Pb > Zn > Mn > As and Cd > Pb > Mn > Zn > As, respectively, under the assumed environmental scenarios, i.e. acid rain, vegetation restoration, human gastrointestinal digestion. The results from mineralogical characterization indicated that quartz, sericite, calcite and pyrite were typical minerals, cumulatively accounting for over 80% of the tailings. Sulfides (arsenopyrite, galena, and sphalerite), carbonates (calcite, dolomite, cerussite and kutnahorite), oxides (limonite) were identified as the most relevant PTEs-bearing phases, which significantly contributed to PTEs release from tailings. A combined result of statistical, geochemical and mineralogical approaches would be provided valuable information for the alteration characteristics and contaminant release of Pb/Zn mine tailings., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Objective: This study was designed to investigate preoperative anxiety situations and postoperative pain degree in Chinese patients undergoing laparoscopic hysterectomy and to analyze the related factors of preoperative anxiety and the correlation between preoperative anxiety and postoperative pain to provide a reference for effective postoperative analgesia management. Methods: A total of 100 female patients undergoing laparoscopic hysterectomy were enrolled in this study and randomly divided into two groups ( n = 50, each). In group A, the patients were treated with dexmedetomidine and sufentanil for postoperative analgesia. In group B, the patients were treated with sufentanil alone for postoperative analgesia. All patients were evaluated with a self-rating anxiety scale (SAS) 1 day before the operation. The patients' pain was evaluated using the numerical rating scale (NRS) 1 day after the operation, and data were recorded. Results: In these 100 patients, the highest preoperative SAS score was 48, and the average score was 40.99 ± 4.55 points, which is higher than the norm in China. There were significant differences in preoperative SAS scores among patients with different occupations and previous surgical experience ( P < 0.05). There was no significant difference in SAS scores among patients with different education levels ( P > 0.05). The postoperative NRS score of group A was significantly higher than that of group B, and the difference was statistically significant ( P < 0.05). The correlation coefficients between SAS scores and NRS scores in groups A and B were 0.836 and 0.870, respectively, presenting with a significantly positive correlation. Conclusion: Preoperative anxiety is an important predictor of postoperative pain. Patients undergoing laparoscopic hysterectomy have preoperative anxiety. The degree of anxiety is influenced by the occupation and previous operation experience of the patients, and patients with higher preoperative anxiety have greater postoperative pain. In addition, we should not neglect the management of postoperative pain because of the small trauma of laparoscopic surgery, and dexmedetomidine combined with sufentanil can improve the postoperative analgesic effect., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Zhang, Hao, Hou, Wu, Jing and Sun.)

BACKGROUND: Substance use is a global mental health issue. There has been limited research exploring the relationships among body, mind, and spirit well-being and the possibility of relapse across different categories of substance users. AIMS: The purpose of the current path analysis was to examine the relationship between body-mind-spirit well-being and the possibility of relapse intention as well as other relevant predictors in people who had a history of substance use. METHODS: A cross-sectional survey was used. Participants were recruited in Southern Taiwan between December 2015 and June 2016. Data were collected from 467 participants who had a history of using controlled substances. RESULTS: Path analysis results revealed that body-mind-spirit well-being was negatively predictive of the possibility of relapse intention. Out of several predictors, stress influence and duration of substance use had direct effects on body-mind-spirit well-being and the possibility of relapse intention, respectively. Stress influence and duration of substance use were associated with decreased body-mind-spirit well-being and increased relapse intention scores. In addition, no history of health problems and male gender were associated with increased body-mind-spirit well-being. CONCLUSIONS: Stress management and the duration of substance use play an important role in body-mind-spirit well-being and relapse intention in people with a history of substance use. Health care professionals could teach substance users coping strategies to address their stress and problems, which may improve their health and reduce the possibility of relapse intention.

The major histocompatibility complex (MHC) has several important roles in kin recognition, pathogen resistance and mate selection. Research in fish, birds and mammals has suggested that individuals optimise MHC diversity, and therefore offspring fitness, when choosing mates. In reptiles, however, it is unclear whether female mate choice is based on genome-wide genetic characteristics such as microsatellite DNA loci, particular functional-trait loci (e.g., MHC) or both, and MHC's effects on mate choice remain relatively understudied. Herein, we used 13 microsatellite loci and two MHC class I loci to investigate female mate choice of Chinese alligators (Alligator sinensis) in the semi-natural condition. We also determined correlations between the MHC genotype of breeding males and male reproductive success. We found that MHC-heterozygous males harbour a greater reproductive success, which probably is the reason that these males are more preferred by the females than MHC-homozygous males. Furthermore, the MHC class I amino-acid distance and functional distance of true mating pairs were higher compared with those of randomly sampled pairs. Analysis of microsatellites revealed that, despite mate choice, females did not completely avoid inbreeding. These findings are the first evidence of MHC-associated mate choice in Chinese alligators, suggesting that females may adopt different mating strategies after assessing the MHC characteristics of potential mates.

Solar water splitting represents one of the most promising strategies in the quest for clean and renewable energy. However, low conversion efficiency, use of sacrificial agents, and external bias for current water splitting system limit its practical application. Here, a gold-sensitized Si/ZnOcore/shell nanowire photoelectrochemical (PEC) cell is reported for efficient solar water oxidation. We demonstrated gold-sensitized n-Si/n-ZnO nanowire arrays exhibited higher energy conversion efficiency than gold-sensitized p-Si/n-ZnO nanowire arrays due to the favorable energy-band alignment characteristics. Without any assistance from an external electrical source and sacrificial reagents, gold-sensitized n-Si/n-ZnO core/shell nanowire array photoanode achieved unbiased water splitting under simulated solar light illumination. This method opens a promising venue to cost-efficient production of solar fuels.

Drug abuse adversely affects the health of populations in many counties and contributes immensely to social issues. Schedule III and IV controlled drug abuse is popular in young adults. Medical education is one of the most stressful academic fields for students. The aim of this study was to compare the health differences in body, mind, and spirit among Schedule III and IV controlled drugs users, nursing students, and psychology students. This study uses a cross-sectional comparative study on a convenience sample. Four hundred eleven participants were recruited from three different samples that include Schedule III and IV controlled drug users (n = 211), nursing students (n = 100), and psychology students (n = 100), all from either a drug abuse prevention center or two universities in Southern Taiwan. Relying on the Health of Body, Mind and Spirit Scale, a linear regression model was used to identify the health differences among drug users, nursing students, and psychology students. The results show that drug users scored higher on the physical subscale (ß = -.249, p < .001), the mental subscale (ß = -.120, p < .05), the spiritual subscale (ß = -.154, p < .01), and the Health of Body, Mind and Spirit Scale (ß = -.210, p < .001) than psychology students. The nursing students scored higher on the mental subscale (ß = .146, p < .01) than drug users did. These results could help health staff and instructors understand the differences and improve the physical, mental, and spiritual health among Schedule III and IV controlled drug users, nursing students, and psychology students. Furthermore, future study could further investigate the factors that may affect physical, mental, and spiritual health.

The therapeutic application of deoxypodophyllotoxin (DPT) is limited due to its poor water solubility and stability. In the present study, the micelles assembled by the amphiphilic block copolymers (mPEG-PDLLA) were constructed to improve the solubility and safety of DPT for their in vitro and in vivo application. The central composite design was utilized to develop the optimal formulation composed of 1221.41 mg mPEG-PDLLA, the weight ratio of 1 : 4 (mPEG-PDLLA : DPT), 30 mL hydration volume and the hydration temperature at 40 °C. The results showed that the micelles exhibited uniformly spherical shape with the diameter of 20 nm. The drug-loading and entrapment efficiency of deoxypodophyllotoxin-polymeric micelles (DPT-PM) were about (20 ± 2.84)% and (98 ± 0.79)%, respectively, indicating that the mathematical models predicted well for the results. Compared to the free DPT, the cytotoxicity showed that blank micelles possessed great safety for Hela cells. In addition, the DPT loaded micelle formulation achieved stronger cytotoxicity at the concentration of 1 × 10 -7 mol·L -1 , which showed significant difference from free DPT (P < 0.05). In conclusion, the micelles were highly promising nano-carriers for the anti-tumor therapy with DPT., (Copyright © 2018 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.)

Voltage-gated sodium (Na V ) channels play vital roles in the signal transduction of excitable cells. Upon activation of a Na V channel, the change of transmembrane voltage triggers conformational change of the voltage sensing domain, which then elicits opening of the pore domain and thus allows an influx of Na + ions. Description of this process with atomistic details is in urgent demand. In this work, we simulated the partial activation process of the voltage sensing domain of a prokaryotic Na V channel using a polarizable force field. We not only observed the conformational change of the voltage sensing domain from resting to preactive state, but also rigorously estimated the free energy profile along the identified reaction pathway. Comparison with the control simulation using an additive force field indicates that voltage-gating thermodynamics of Na V channels may be inaccurately described without considering the electrostatic polarization effect.

Accidental displacement of end osseous implants into the maxillary sinus is an uncommon but potential complication in implant surgery due to the special features of the posterior aspect of the maxillary bone. The authors reported one case implant displacement into the maxillary sinus by lateral window technique. The causes for displacement, preventive measures were summarized, in order to avoid this kind of complication.

Realization of broadband optical absorption enhancement in thin film c-Si solar cells is essential for improving energy conversion efficiency and reducing cost. Here, we demonstrate the fabrication of randomly arranged silicon nanorocket (SiNR) arrays as a new light trapping structure design for thin film silicon solar cells. The optical absorption of the randomly arranged SiNR arrays is investigated via finite-difference-frequency-domain (FDTD) simulation. Our calculations reveal that the light trapping structures facilitate the coupling of incident sunlight into the resonant modes and lead to significant photon absorption enhancement across a wide solar spectrum, resulting in ultimate efficiencies superior to nanowire and nanohole arrays with the same thickness. Our findings indicate that the randomly arranged SiNR arrays fabricated by the simple self-assembly and etching approach can have a significant impact on performance improvement in thin film silicon solar cells.

Inspired by metal corrosion in air, we demonstrate that metal-catalyzed electroless etching (MCEE) of silicon can be performed simply in aerated HF/H2O vapor for facile fabrication of three-dimensional silicon nanostructures such as silicon nanowires (SiNW) arrays. Compared to MCEE commonly performed in aqueous HF solution, the present pseudo gas phase etching offers exceptional simplicity, flexibility, environmental friendliness, and scalability for the fabrication of three-dimensional silicon nanostructures with considerable depths because of replacement of harsh oxidants such as H2O2 and AgNO3 by environmental-green and ubiquitous oxygen in air, minimum water consumption, and full utilization of HF.

Based on previous report that the Chinese herb Ligustrum lucidum (LL) extract directly inhibited hepatitis C virus (HCV) replicase (NS5B) activity, the active components of LL extract to inhibit HCV NS5B activity and their inhibition mode were investigated in this study. LL extract was separated using ethyl acetate and thin layer chromatography (TLC). The inhibitory activity of separated fractions on HCV NS5B was analyzed by the inhibitory assay of NS5B activity. The results showed that only fractions 1 and 2 inhibited NS5B activity, and fraction 2 possessed higher inhibitory activity than fraction 1. HPLC analysis combined with inhibitory assays indicated that ursolic acid and oleanolic acid are the active components within fractions 1 and 2 to inhibit NS5B activity, separately. Moreover, oleanolic acid possessed higher inhibitory activity than ursolic acid. Further inhibition mode analysis found that both oleanolic acid and ursolic acid suppressed NS5B activity as noncompetitive inhibitors. The Ki values of ursolic acid and oleanolic acid were about 4.7 microg x mL(-1) (10 micromol x kg(-1)) and 2.5 microg x mL(-1) (5.5 micromol x kg(-1)), respectively. Taken together, these results demonstrated that oleanolic acid and ursolic acid suppressed NS5B activity as noncompetitive inhibitors, implying that the two natural products have potential value for HCV therapy.