Edge-sharing bi-octahedral diruthenium(IV,IV) compounds containing Ru-Ru bonds chelated and bridged by two carbonate and two oxo groups.

From paddle-wheel starting material Na3Ru2(CO3)4·6H2O, a family of edge-sharing bi-octahedral (ESBO) diruthenium(IV,IV) compounds formulated as Ru2O2(CO3)2(H2O)2L2·nH2O [L = piperazine (1) or 2-methylpiperazine (2), n = 4, and L = 2,2-dimethylpiperazine (3), n = 12] and Ru2O2(CO3)2(OH)4{M(H2O)4}2·nH2O [M = Mg (4), n = 4, and Ni (5), n = 2] were prepared and structurally characterized. The Ru28+ dimer is chelated and bridged by two CO32- and two µ-O in a trans manner, and the Ru-Ru distances fall in the range 2.3808(6)-2.4001(4) Å. Compound 2 shows the shortest Ru-Ru distance for all known ESBO Ru2 compounds reported thus far. Increasing -CH3 groups of terminal piperazine ligands coordinated to the Ru(µ-O)2(µ-O3C)2Ru core, and according to Raman spectra experiments combined with theoretical calculations, the intense bands of compounds 1-3 appearing at ∼360 cm-1 can be assigned to the stretching of Ru-Ru bonds.

A family of edge-sharing bi-octahedral diruthenium(III,III) compounds containing Ru-Ru single bonds.

From paddlewheel starting reactants Ru2(R'CO2)4+, a family of edge-sharing bi-octahedral (ESBO) diruthenium(III,III) compounds has been prepared, formulated as Ru2(µ-O2CR')2(µ-OR)2(η-L)2 (1-10) [R' = CH3, R = CH3, L = acac (1), tfac (2); R' = CH3, R = CH2CH3, L = hfac (3); R' = CH2CH3, R = CH3, L = acac (4), tfac (5); R' = CH2CH3, R = CH2CH3, L = hfac (6); R' = CH2Cl, R = CH3, L = tfac (7); R' = CH2Cl, R = CH2CH3, L = hfac (8); R' = C6H5, R = CH3, L = tfac (9); and R' = H, R = CH3, L = acac (10); here, acac, tfac and hfac represent acetylacetone, trifluoroacetylacetone and hexafluoroacetylacetone, respectively]. Compounds 1-10 have a similar ESBO coordination geometry of the Ru(µ-O2CR')2(µ-OR)2Ru core with a Ru-Ru center chelated and bridged by two µ-O2CR' and two µ-OR in a trans manner, and each Ru center is also coordinated with a η2-L bidentate ligand. The Ru-Ru distances fall in the range of 2.4560(9)-2.4771(4) Å. The investigation of the electronic spectra and vibrational frequencies as well as theoretical studies with density functional theory (DFT) reveal that compounds 1-10 are ESBO bimetallic species of d5-d5 valence electron counts showing a σ2π2δ2δ*2π*2 electronic configuration. Varying -CH3 to -CF3 groups on the η2-L bidentate ligands coordinating to the Ru(µ-O2CR')2(µ-OR)2Ru core, and according to Raman spectrum measurements combined with theoretical calculations, the intense bands of compounds 1-10 appearing at ∼345 cm-1 in the small-wavenumber region can be assigned to the stretching of the Ru-Ru single bond.

Homo-valent diruthenium(II,II) carbonates Na4[Ru2(CO3)4]·10H2O: synthesis, structure, properties, and calculation.

Homo-valent diruthenium(II,II) carbonates have been underexplored hitherto. This paper reports the synthesis and crystal structure of a diruthenium(II,II) compound, Na4Ru2(CO3)4·10H2O (1). It has a two-dimensional structure in which the paddle-wheel diruthenium units of Ru2(CO3)44- are cross-linked through the carbonate groups. The investigation of the primary magnetic properties and theoretical studies with density functional theory (DFT) reveal that weak antiferromagnetic interactions are propagated between the Ru2 units which contain two unpaired electrons in an electron configuration σ2π4δ2π*2δ*2 with a ground state S = 1. According to Raman spectrum measurements combined with theoretical calculations, the strong peak at 356 cm-1 in the small-wavenumber region was assigned to the stretching of the Ru-Ru double bonds.

Silencing of circ-NT5C2 retards the progression of IL-1ß-induced osteoarthritis in an in vitro cell model by targeting the miR-142-5p/NAMPT axis.

Osteoarthritis (OA) is a degenerative disease that occurs mostly in the elderly, and its specific pathogenesis is still unknown, but recent studies have found that circular RNA generally display aberrant expression in OA. Our study explored the expression characteristics and mechanism of action of circ-NT5C2 in OA. Circ-NT5C2, microRNA-142-5p (miR-142-5p), and nicotinamide phosphoribosyltransferase (NAMPT) mRNA levels were measured using RT-qPCR. Western blot was employed to assess the protein level of NAMPT and extracellular matrix (ECM) production-related markers. The viability, proliferation, apoptosis and inflammation were examined using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, 5-ethynyl-2'-deoxyuridine (EdU) assay, flow cytometry, and enzyme-linked immunosorbent assay, respectively. Relationship between miR-142-5p and circ-NT5C2 or NAMPT was demonstrated by dual-luciferase reporter system and RNA immunoprecipitation assay. We reported that circ-NT5C2 and NAMPT were greatly upregulated, and miR-142-5p level was constrained in OA tissues and in a cell model. Circ-NT5C2 silencing alleviated IL-1ß-induced inhibitory effects on chondrocyte proliferation and ECM generation, meanwhile the promotional role of IL-1ß on chondrocyte apoptosis and inflammation was also weakened. The targeting relationship of miR-142-5p with either circ-NT5C2 or NAMPT was confirmed. Knockdown of miR-142-5p reversed the suppressive effects of circ-NT5C2 silencing on the OA progression in vitro, and NAMPT overexpression also attenuated the effects of miR-142-5p upregulation in an OA cell model. Collectively, circ-NT5C2 accelerated the OA process by targeting the miR-142-5p/NAMPT axis. This study provides valuable information to find a better treatment for OA.

Maternal exposure to cooking oil fumes during pregnancy and autistic-like behaviors in Chinese preschoolers.

There is growing evidence that cooking oil fumes (COFs) are harmful indoor air pollutants. However, there is a dearth of research investigating whether maternal COFs exposure during pregnancy may affect children's autistic-like behaviors in China. This study aimed to explore this association, and examine the effects of different cooking fuels and ventilation methods used by mothers on the presence of autistic-like behaviors. This study analyzed the survey data of the Longhua Child Cohort Study in 2017 with a total of 62,372 mothers enrolled in this study. A self-administrative questionnaire was used to collect information on socio-demographic characteristics, cooking habits during pregnancy, and autistic-like behaviors (measured using the Autism Behavior Checklist). After adjusting for potential confounders, the results showed that compared with children whose mothers never cooked during pregnancy, children whose mothers cooked sometimes, often, always during pregnancy had the higher risk of autistic-like behaviors. As the amounts of COFs exposed to and the frequency of cooking during pregnancy increased, the risk of a child's autistic-like behaviors also increased. Mothers using natural gas as cooking fuels had a lower risk of their child having autistic-like behaviors, compared with mothers using coal or other cooking fuels. Furthermore, pregnant women using ventilation measures during cooking significantly decreased likelihood of the presence of autistic-like behaviors in their children. These results suggest that maternal exposure to COFs during pregnancy may increase the likelihood of the presence of autistic-like behaviors in offspring. These findings support a recommendation that pregnant women should avoid exposure to COFs and use clean fuels and ventilation equipment in kitchens to reduce the risk of autistic-like behaviors in children.

Association between prenatal exposure to indoor air pollution and autistic-like behaviors among preschool children.

Indoor air pollution is a recognized risk factor for a range of negative health outcomes. This study aimed to investigate the association between maternal prenatal exposure to indoor air pollution and the presence of autistic-like behaviors among preschool children. Data were obtained from the Longhua Child Cohort Study in 2017, in which we enrolled a total of 65 317 preschool children. Associations between maternal exposure to four sources of indoor air pollution (e.g., cooking, environmental tobacco smoke (ETS), mosquito coils, and home decoration) during pregnancy and preschool children's autistic traits were analyzed using multivariate logistic regression. Our results showed that maternal exposure to indoor air pollution from four different sources during pregnancy was associated with the presence of children's autistic-like behaviors. There was dose-response relationship between the accumulative exposure to the four different indoor air pollution sources and the risk of autistic-like behaviors. Furthermore, we found a significant additive interaction between prenatal exposure to both cooking and mosquito coil incense on the risk of autistic-like behaviors. Maternal prenatal exposure to the indoor air pollution from four sources might increase with the risk of autistic-like behaviors being present among preschool children, with an additive interaction effect between some pollution sources.

Association between environmental tobacco smoke exposure in early life and autistic-like behaviors in Chinese preschoolers.

OBJECTIVE: Few studies have evaluated the association between children's exposure to environmental tobacco smoke (ETS) in early life (during pregnancy, from birth to one year and from one to three years) and autistic-like behaviors. This study aimed to explore this association. METHODS: This cross-sectional study analyzed data collected in 2017 as part of the Longhua Child Cohort Study. Autistic-like behaviors were measured using the Autism Behavior Checklist (ABC). Data on ETS exposure and autistic-like behaviors of children were collected via self-administered questionnaires completed by the mothers. Multivariate logistic regression models were undertaken to assess the associations. RESULTS: Of the 65,243 participants included in this study, 1958 children met criteria for having autistic-like behaviors. The results showed that children were more likely to exhibit autistic-like behaviors when they were exposed to ETS in early life (AOR = 1.38; 95% CI = 1.26-1.52), compared to preschoolers without ETS exposure at any period of their early life. Compared with their unexposed counterparts, children who were exposed to ETS during gestation (AOR = 1.42; 95% CI = 1.29-1.57), or from birth to one year old (AOR = 1.42; 95% CI = 1.19-1.69) had significantly increased risk of autistic-like behaviors. In addition, with the increase in duration of exposure and average number of cigarettes smoked in the child's immediate environment, the risk of autistic-like behaviors increased. CONCLUSION: Our study indicated that children's ETS exposure in early life was significantly associated with autistic-like behaviors. When children's exposure to cigarettes in early life increased in duration and number, the likelihood of the presence of autistic-like behaviors was higher.

Interlayer hydrogen bonding directed magnetic properties for a different number of water-intercalated structural heterometallic phosphates based on paddlewheel units Ru2(PO4)46.

Layered heterometallic phosphates {Mn(H2O)4}2Mn(H2O)2Ru2(PO4)4(H2O)2 (1) with a new topology were constructed from Ru2(PO4)46- and Mn2+ in the presence of anions as assisting reactants whose alkaline strength plays a key role in directing a different number of lattice water-intercalated structures. In the presence of CO32- and SO42- as assisting reactants, the assembling reaction in the aqueous solution at room temperature results in compounds 1·10H2O and 1·4H2O, respectively. Single-crystal X-ray diffraction analysis reveals that compounds 1·10H2O and 1·4H2O crystallize in orthorhombic space group Pbca and monoclinic space group P21/c, respectively. The layered structure of 1 is constructed by alternating Ru2O10 tetragonal dipyramid and MnO6 octahedra bridged by PO4 tetrahedra. The neutral heterometallic phosphate layers of 1 are separated by a different number of interlayer lattice water molecules, and hydrogen bonds are responsible for the neutral inorganic layer connection. Magnetism measurements show that compound 1·10H2O exhibits a soft magnet behaviour ordering below 8.5 K with indirect hydrogen bonding between these ferrimagnetic layers, and a reentrant spin-glass-like transition is observed for compound 1·4H2O, exhibiting two steps transition at 8.0 and 12 K, due to a strong competition between intralayer magnetic coupling and interlayer antiferromagnetic interactions mediated through the direct hydrogen bonding.

Chromous carbonates containing a square-grid layer of {Cr2(CO3)4}n4n- based on a dichromium(II,II) paddlewheel core.

Polymeric coordination compounds based on Cr2n+ paddle-wheel building blocks with non-carboxylate O,O-donor ligands chelating and bridging the Cr-Cr centers have been underexplored hitherto. This paper reports the synthesis and crystal structure of a new homo-valent chromium(ii,ii) compound, Na3HCr2(CO3)4·10H2O (1). It has a two-dimensional structure in which the paddlewheel chromium(ii,ii) units of Cr2(CO3)44- are cross-linked through the carbonate groups. The layers are stacked along the [100] direction, and Na ions fill the intra and interlayer spaces with a neighboring layer distance of about 11.3 Å. The investigation of the primary magnetic properties and theoretical studies with density functional theory (DFT) reveal the partial paramagnetic properties of compound 1 arising from the Boltzmann distribution between a ground state σ2π4δ2 with S = 0 and a low-lying excited state σ2π4δδ* with S = 1 for the Cr2(ii,ii) dimer. According to Raman spectra measurements combined with theoretical calculations, the two Raman bands in the small-wavenumber region at 335 and 297 cm-1 were assigned to the vibration of the Cr-O bonds and the band at 371 cm-1 was assigned to the stretching of the Cr-Cr quadruple bond.

Associations between Prenatal Education, Breastfeeding and Autistic-Like Behaviors in Pre-Schoolers.

This study aimed to investigate the association between prenatal education and autistic-like behaviors of preschoolers as well as the mediating role of breastfeeding in their associations. A cross-sectional study via a structured questionnaire was conducted with 67,578 preschool children and parents from Longhua District of Shenzhen, China. Hierarchical logistic regression models were performed to explore the associations between maternal participation in prenatal education and autistic-like behaviors in preschoolers, as well as the mediating effect of breastfeeding in the associations. After controlling for potential confounders, logistic regression analysis indicated that maternal participation in prenatal education could significantly increase the prevalence of breastfeeding, and the strength of the association was enhanced with the increase frequency of prenatal education visits (ORs ranging from 1.191 to 1.899). While both maternal participation in prenatal education (ORs ranging from 0.732 to 0.798) and breastfeeding (OR = 0.773) were significantly associated with the lower presence of autistic-like behaviors in preschoolers. The crossover analysis indicated that children with both maternal prenatal education and breastfeeding had the lower risk of presence of autistics-like behaviors (OR = 0.569). Furthermore, mediation analysis illustrated that breastfeeding mediated the association between maternal participation in prenatal education and the presence of autistic-like behaviors in preschoolers, with a mediating effect of approximately 14.3%. Our findings suggest that maternal participation in prenatal education is significantly associated with a decreased risk of autistic-like behaviors in preschool children through increased breastfeeding in the mothers who attended prenatal education.

Grinding enhances the magnetic hardness of heterometallic diruthenium(ii,iii) carbonates with a kagome lattice structure.

The assembly of paddle-wheel Ru2 building units affords a new trimetallic carbonate, Cs3Cd(H2O)6[{Cd(H2O)3}2{Ru2(CO3)4}3]·10H2O (1), that contains structurally near-perfect kagome layers, {Ru2(CO3)4}n3n-, linked by octahedral Cd(H2O)32+ into a nanoscale kagome network exhibiting ferromagnetic ordering below 3.5 K. The investigation of influences of the grinding method on the crystal samples of compound 1 reveals that the coercivity increases from ∼2.5 Oe to 44.0 Oe upon a grinding treatment for 180 minutes. The results demonstrate that compound 1 can vary from a soft magnet to a hard magnet simply by manually grinding the crystal samples to the nanoscale.

Enhancing magnetic hardness by sonication assisted synthesis of heterometallic carbonato spin-glass Na[Ni(H2O)4Ru2(CO3)4]·3H2O.

Control of magnetic performances of molecular magnets is essential but few efforts have been documented. A green and efficient sonication assisted synthesis of a new heterometallic diruthenium(ii,iii) carbonate, Na[Ni(H2O)4Ru2(CO3)4]·3H2O (1), was carried out by self-assembling in aqueous solution. Compound 1 exhibits spin-glass behavior below ∼5.0 K, and a systematic investigation of the ultrasonic irradiation influence on the powder samples reveals that their coercivity increases from 50 Oe to 743 Oe with the control of ultrasonic power under appropriate conditions.

Complete duodenal obstruction induced by groove pancreatitis: A case report.

BACKGROUND: Groove pancreatitis (GP) is a type of chronic pancreatitis occurring in an anatomic area between the duodenum, head of the pancreas, and common bile duct. Duodenal obstruction is always caused by malignant pancreatic diseases, such as pancreatic head carcinoma, while is rarely induced by benign pancreatic diseases, such as pancreatitis. CASE SUMMARY: A 39-year-old man presented with a 1-mo history of upper abdominal discomfort. His concomitant symptoms were abdominal distension, postprandial nausea, and vomiting. Contrast-enhanced computed tomography of the abdomen showed thickening of the intestinal wall with enhancement of the descending segment of the duodenum, which could not be clearly differentiated from the head of the pancreas. Upper gastrointestinal radiographs and gastrointestinal endoscopy showed a complete obstruction of the descending duodenum. An operation found that a 3-cm mass was located in the "groove part" of the pancreas and oppressing the descending duodenum. Pancreaticoduodenectomy was performed to relieve the obstruction and thoroughly remove the pancreatic lesions. The pathologic diagnosis was pancreatitis. The patient had an uneventful recovery with no complications. CONCLUSION: Because of the special location and the contracture induced by long-term chronic inflammation, our case reminds surgeons that some benign pancreatic diseases, such as GP, can also present with symptoms similar to those of pancreatic cancer. This knowledge can help to avoid an unnecessary radical operation.

Alkali counterions tune diruthenium(iii,iii)-based ferrimagnetic chain structured antiferromagnets exhibiting step-like hysteresis loops.

The synthesis of antiferromagnets (AFMs) has attracted extensive attention in the area of magnetic devices, such as spintronics and memory devices. Following our initial work on the employment of the homo-valent diruthenium(iii,iii) paddle wheel species with high spin states (S = 2) as building blocks and active components for the construction of molecule-based magnetic materials, the reaction of mixed-valent diruthenium(ii,iii) phosphates Ru2(H2PO4)2(H1.5PO4)2(H2O)2·2H2O (1) with H2O2, Cu2+ and ACl (A = K, Rb and Cs) in aqueous solution led to the formation of heterometallic copper diruthenium(iii,iii) phosphates A2[Cu(H2O)4Ru2(HPO4)2(PO4)2(H2O)2]·nH2O [A = K (2); A = Rb and n = 2 (3); A = Cs and n = 3 (4)]. The compounds consist of chain structures in which each octahedral environment of Cu(H2O)42+ bonds to two [Ru(HPO4)2(PO4)2]2- units in a trans manner, forming a ferrimagnetic negative chain {Cu(H2O)4Ru2(HPO4)2(PO4)2(H2O)2}n2n-, exhibiting anomalous magnetic properties. Long-range ordering temperatures, Tc, were observed around 10 K, and the control of the chain structured antiferromagnets exhibiting step-like hysteresis loops was successfully achieved through counterion tuning by replacing K with either Rb or Cs.

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We examined the substitution efficiency of agro-chemical input intensity from 2000 to 2016 in China by employing SE-DEA model and Gini coefficient, and analyzed the driving factors of substitution efficiency with Tobit model. The results showed that the comprehensive efficiency and the scale efficiency of substitution of agro-chemical input intensity displayed the trend of "N-shaped", while the pure technical efficiency was enhanced with some fluctuations. The regional diffe-rences of substitution efficiency were obvious, with the eastern region relying more heavily on the input scale of substitution factors. The most salient provincial-regional difference was the comprehensive efficiency, followed by the pure technical efficiency, and the least salient regional diffe-rence was the scale efficiency nationwide. The provincial-regional difference decreased year by year within each region. The Eastern region's provincial-regional difference was the greatest. The substitution efficiency was significantly affected by agricultural technology level, farmers' income level, agricultural production structure, agricultural development level and industrialization level. Besides, there were obvious differences in the influencing factors among regions. To promote the substitution efficiency of agro-chemical input, it is necessary to improve the efficiency of substitution factors of agro-chemical input intensity, to adjust the development structure of agro-industry, to pay attention to farmers' income level, and to revise the subsidy policy of substitution of agricultural chemical input intensity.

Prescribing errors in electronic prescriptions for outpatients intercepted by pharmacists and the impact of prescribing workload on error rate in a Chinese tertiary-care women and children's hospital.

BACKGROUND: Prescribing errors may, influenced by some risk factors, cause adverse drug events. Most studies in this field focus on errors in prescriptions for hospital inpatients, with only a few on those for outpatients. Our study aimed to explore the incidence of prescribing errors in electronic prescriptions and illustrate the trend of prescribing workload and error rate over time. METHODS: The cross-section study was performed between September, 2015 and November, 2015. Prescribing errors were intercepted by pharmacists using a prescription reviewing system under which prescriptions with errors were transferred to a specific computer and recorded by another pharmacist and the incidence of total prescribing errors and severe errors was then calculated. A subgroup analysis was conducted in accordance to the number of drug orders, the age group of patients, the seniority of physicians, the specialty of physicians, the working day when prescriptions were issued, and the prescribing workload of physicians. A time-series analysis was employed to analyze the trend of prescribing workload and error rate, and the correlation between them. RESULTS: Totally, 65,407 patients were included in this study and 150,611 prescriptions with 294,564 drug orders (including 584 different drugs) were reviewed for identification of errors. A total of 534 prescribing errors (an error rate of 0.34%) were identified. Severe errors accounted for 13.62% of total errors. The subgroup analysis showed prescriptions of multiple drug orders, for pediatric patients aged 29 days to 12 years, from physicians specializing in ophthalmology and otorhinolaryngology, or prescribing on weekdays were more susceptible to errors. A time-series analysis demonstrated no correlation between prescribing workload and error rate which increased at the end of each working shift while prescribing workload decreased. CONCLUSION: Less than 1% of the studied prescriptions came with errors among which one in seven were severe ones. But prescribing errors were in no relation to workloads. What's more, further studies are needed to investigate pharmacist-led intervention to reduce prescribing errors.

Vancomycin-induced severe thrombocytopenia in a young infant.

Vancomycin is a first-line drug for treating methicillin-resistant Staphylococcus aureus. Thrombocytopenia is a rare adverse reaction to vancomycin treatment, and there are no reports of vancomycin-induced thrombocytopenia (VIT) in infants. We describe the case of a 3-month-old girl who was diagnosed with purulent meningitis. After 13 days of treatment with vancomycin, her platelet count reduced to 8 × 109/L. Vancomycin was discontinued, and intravenous methylprednisolone was administered. The platelet count returned to normal after 4 days. Patients, especially young children, receiving vancomycin for a long clinical course should undergo careful monitoring of laboratory indicators and blood tests.

Vancomycin-induced severe thrombocytopenia in a young infant

Abstract Vancomycin is a first-line drug for treating methicillin-resistant Staphylococcus aureus. Thrombocytopenia is a rare adverse reaction to vancomycin treatment, and there are no reports of vancomycin-induced thrombocytopenia (VIT) in infants. We describe the case of a 3-month-old girl who was diagnosed with purulent meningitis. After 13 days of treatment with vancomycin, her platelet count reduced to 8 × 109/L. Vancomycin was discontinued, and intravenous methylprednisolone was administered. The platelet count returned to normal after 4 days. Patients, especially young children, receiving vancomycin for a long clinical course should undergo careful monitoring of laboratory indicators and blood tests.

Identification of MGMT promoter methylation sites correlating with gene expression and IDH1 mutation in gliomas.

O6-methylguanine-DNA methyltransferase (MGMT) gene promoter methylation was reported to be an independent prognostic and predictive factor in glioma patients who received temozolomide treatment. However, the predictive value of MGMT methylation was recently questioned by several large clinical studies. The purpose of this study is to identify MGMT gene promoter CpG sites or region whose methylation were closely correlated with its gene expression to elucidate this contradictory clinical observations. The methylation status for all CpG dinucleotides in MGMT promoter and first exon region were determined in 42 Chinese glioma patients, which were then correlated with MGMT gene expression, IDH1 mutation, and tumor grade. In whole 87 CpG dinucleotides analyzed, three distinct CpG regions covering 28 CpG dinucleotides were significantly correlated with MGMT gene expression; 10 CpG dinucleotides were significantly correlated with glioma classification (p < 0.05). Isocitrate dehydrogenase 1 (IDH1) mutation and MGMT gene hypermethylation significantly co-existed, but not for MGMT gene expression. The validation cohort of gliomas treated with standard of care and comparison of the CpGs we identified with the current CpGs used in clinical setting will be very important for gliomas individual medicine in the future.

Echinocystic acid inhibits RANKL-induced osteoclastogenesis by regulating NF-κB and ERK signaling pathways.

Receptor activator of nuclear factor-κB ligand (RANKL) is a key factor in the differentiation and activation of osteoclasts. Echinocystic acid (EA), a pentacyclic triterpene isolated from the fruits of Gleditsia sinensis Lam, was reported to prevent reduction of bone mass and strength and improve the cancellous bone structure and biochemical properties in ovariectomy rats. However, the molecular mechanism of EA on the osteoclast formation has not been reported. The purpose of this study was to investigate the effects and mechanism of EA on RANKL-induced osteoclastogenesis. Our results showed that EA inhibited the formation of osteoclast, as well as the expression of osteoclastogenesis-related marker proteins in bone marrow macrophages (BMMs). At molecular levels, EA inhibited RANKL-induced NF-κB activation and ERK phosphorylation in BMMs. In conclusion, the present study demonstrated that EA can suppress osteoclastogenesis in vitro. Moreover, we clarified that these inhibitory effects of EA occur through suppression of NF-κB and ERK activation. Therefore, EA may be a potential agent in the treatment of osteoclast-related diseases such as osteoporosis.