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A study on the phytochemical composition of the roots of Polygonum multiflorum collecting in Vietnam and an evaluation of its capacity to inhibit pancreatic lipase enzyme was conducted. In total, 12 metabolites (1 – 12) were isolated from anti-lipase activity-guided fractionation of P. multiflorum. The isolated compounds (1 – 12) were identified as trans -resveratrol (1), methyl protocatechuate (2), methyl gallate (3), catechin (4), epicatechin (5), myrciaphenone A (6), quercetin (7), kaempferol (8), apigenin (9), luteolin (10), tricin (11), and afzelin (12). This is the first time Compound 12 has been reported from P. multiflorum. However, 12 second metabolites (1 – 12) were tested in vitro to assess the anti-lipase potential. The results revealed Compound 7 exhibited the most significant lipase inhibition, with an IC50 value of 0.30 ± 0.04 μM. Following closely, Compounds 6, 8, 10, and 12 displayed IC50 values of 5.38 ± 0.65, 0.72 ± 0.10, 0.79 ± 0.19, and 1.22 ± 0.18 μM, respectively. For comparison, orlistat (positive control), the most common anti-obesity drug available on the market, has an IC50 value of 0.91 ± 0.10 μM. Molecular docking was applied to explore the affinity and interactions between active compounds 6 – 8, 10, and 12 and proteins associated with obesity, namely pancreatic lipase–colipase complex (PLCC) and pancreatic lipase-related protein 1 (PLRP1). In addition, absorption, distribution, metabolism, excretion, and toxicity (ADMET) were used in predictions. The results indicate that the active compounds isolated from P. multiflorum could be further in-depth research on lipase inhibition. [ABSTRACT FROM AUTHOR]

Seven metabolites (1 – 7) were isolated from the Vietnamese Scutellaria indica, guided by anti-inflammatory activity. The identified compounds comprise scrocaffeside A (1), naringenin-7-O-glucoside (2), darendoside B (3), decaffeoylverbascoside (4), plantainoside C (5), acteoside (6), and isoacteoside (7). This is the first time the compounds 1 – 3 and 5 were isolated from the entire Scutellaria indica. Compounds 1 – 7 tested for their anti-inflammatory potential by inhibiting nitric oxide (NO) production. Compound 1 showed the most activity (IC50 = 31.4 μM), followed by compounds 2, 4, 6, and 7 exhibited IC50 values of 41.2, 87.4, 52.2, and 44.6 μM, respectively. However, compounds 3 and 5 were inactive (IC50 > 100 μM). Molecular docking was applied to study the affinity and interactions between compound 1 and inflammatory-caused proteins based on the in vitro results. Compound 1 generated the lowest binding free energy with the cyclooxygenase-2 (COX-2) target, which was −9.8 kcal/mol, followed by inducible nitric oxide synthase (iNOS, –8.4 kcal/mol), and interleukin-8 (IL-8, –7.6 kcal/mol). The results indicate that compound 1 derived from S. indica has the potential to be further explored and developed as an inflammatory inhibitor. [ABSTRACT FROM AUTHOR]

Smart contracts are decentralized applications that hold a pivotal role in blockchain-based systems. Smart contracts are composed of error-prone programming languages, so it is affected by many vulnerabilities (e.g., time dependence, outdated version, etc.), which can result in a substantial economic loss within the blockchain ecosystem. Therefore, many vulnerability detection tools are designed to detect the vulnerabilities in smart contracts such as Slither, Mythrill and so forth. However, these tools require high processing time and cannot achieve good accuracy with complex smart contracts nowadays. Consequently, many studies have shifted towards using Deep Learning (DL) techniques, which consider bytecode to determine vulnerabilities in smart contracts. However, these mechanisms reveal three main limitations. First, these mechanisms focus on multi-class problems, assuming that a given smart contract contains only a single vulnerability while the smart contract can contain more than one vulnerability. Second, these approaches encounter ineffective word embedding with large input sequences. Third, the learning model in these mechanisms is forced to classify into one of pre-defined labels even when it cannot make decisions accurately, leading to misclassifications. Therefore, in this paper, we propose a multi-label vulnerability classification mechanism using a language model. To deal with the ineffective word embedding, the proposed mechanism not only takes into account the implicit features derived from the language models (e.g., SecBERT, etc.) but also auxiliary features extracted from other word embedding techniques (e.g., TF-IDF, etc.). Besides, a trustworthy neural network model is proposed to reduce the misclassification rate of vulnerability classification. In detail, an additional neuron is added to the output of the model to indicate whether the model is able to make decisions accurately or not. The experimental results illustrate that the trustworthy model outperforms benchmarks (e.g., binary relevance, label powerset, classifier chain, etc.), achieving up to approximately 98% f1-score while requiring low execution time with 26 ms. [ABSTRACT FROM AUTHOR]

Poor pelleting ability of rice straw (RS) discourages its production and utilization as a biofuel. Woody biomass and lignin are believed to improve the quality of herbaceous and agro-residual pellets. This study investigated the influence of length-to-diameter ratio (L / φ = 6 and 10), pine sawdust (PS) (0, 20, and 40 wt%) and sodium lignosulfonate (SL) (0, 10 and 20 wt%) on the quality of RS pellets produced via a mini-pilot scale flat-die pellet mill. L / φ positively affected quality of RS pellets and specific energy consumption (SEC) of pelleting process. PS improved significantly the energy content and reduced the ash content of the RS pellets simultaneously, however, it decreased the true, bulk densities and tensile strength of RS pellets. SL positively influenced pellet physical properties for SL up to 10%. Average unit, bulk, tapped densities and tensile strength of RS pellets were 1272–1330 kg m−3, 596–687 kg m−3, 661–760 kg m−3, and 4.4–5.6 MPa in L / φ = 6 and L / φ = 10, respectively. PS remarkably affected combustion behavior of RS pellets, however the effect of SL was not critical. The SEC of pelleting process ranged between 1.9 and 2.7 GJ t−1 in L / φ = 6 and 2.4–3.6 GJ t−1 in L / φ = 10. The corresponding energy ratios were 3.1–4.4 and 2.5–3.6, respectively. The optimal heating value and energy density were 15.79 MJ kg−1 and 9102.81 MJ m−3 in L / φ = 6, and 15.27 MJ kg−1 and 10818.08 MJ m−3 in L / φ = 10. • Pine sawdust (PS) improved rice straw (RS) pellet's energy content. • PS lowered pelleting's energy consumption and pellet physical properties. • Sodium lignosulfonate (SL) enhanced physical properties of pellets but added ash. • Combustion behavior of RS pellets significantly affected by PS but SL. • Quadratic model predicted well pellet quality by compression, PS, and SL ratios. [ABSTRACT FROM AUTHOR]

Predicting CPU usage is crucial to cloud resource management. Precise CPU prediction, however, is a tough challenge due to the variable and dynamic nature of CPUs. In this paper, we introduce TrAdaBoost.WLP, a novel regression transfer boosting method that employs Long Short-Term Memory (LSTM) networks for CPU consumption prediction. Concretely, a dedicated Periodicity-aware LSTM (PA-LSTM) model is specifically developed to take into account the use of periodically repeated patterns in time series data while making predictions. To adjust for variations in CPU demands, multiple PA-LSTMs are trained and concatenated in TrAdaBoost.WLP using a boosting mechanism. TrAdaBoost.WLP and benchmarks have been thoroughly evaluated on two datasets: 160 Microsoft Azure VMs and 8 Google cluster traces. The experimental results show that TrAdaBoost.WLP can produce promising performance, improving by 32.4% and 59.3% in terms of mean squared error compared to the standard Probabilistic LSTM and ARIMA. [ABSTRACT FROM AUTHOR]

In this study, optimization of solid-state fermentation of Camelina sativa residues (camelina straw, CS) and Panicum virgatum (switchgrass, SG) by Trametes versicolor 52J (TV52J), Trametes versicolor m4D (TVm4D), and Phanerochaete chrysosporium (PC) was conducted. At optimal conditions, the tensile strength, unit density and mass loss for CS pellets were 6.2 MPa, 1139 kg m−3, and 33%, respectively after 31 d pretreatment by TVm4D, while for SG pellets, they were 1.6 MPa, 1244 kg m−3 , and 13.8%, respectively after 32 d pretreatment by TVm4D. Although the holocellulose content of microbially pretreated CS and SG pellets dropped from 58.6 to 36.7%, and from 66.2 to 46.3%, respectively, the glucose yield of CS pellets increased from 12.9 to 61.1% with a corresponding xylose yield increase from 14.7 to 60.1%. The glucose and xylose yield of SG increased from 10.9 to 59.9% and 13.4 to 35.7%, respectively. It can be concluded that microbial pretreatment contributed to mass loss of the samples but trivially affected the energy content and significantly boosted the physical properties and enzymatic digestibility of the treated pellets. The microbially pretreated CS is recommended for densification and combustion while the microbially pretreated SG is more suitable for biochemical conversion. [Display omitted] • Pretreatment using white-rot fungi can improve pellet physical quality. • Camelina straw pellets are suitable for thermal conversion. • Switchgrass pellets can be used for biorefinery. • Pellet enzymatic digestibility was enhanced by white-rot fungal pretreatment. • On-farm indoor wet storage fungal pretreatment and densification are promising. [ABSTRACT FROM AUTHOR]

This paper studies the selective maintenance problem for multi-state series systems working in variable loading conditions in the next mission. In the mission, a component's degradation depends on its current state and the load applied on it. A load-dependent degradation model is proposed for multi-state components operating in variable loading conditions. This model is inspired by the load-sharing model where many components share a common workload and the failure rate of a component depends on the state of other components. A Monte-Carlo simulation method is presented to simulate the multi-state component's degradation and to evaluate the system reliability. The final objective is to determine the best selective maintenance strategy to maximize the expected system reliability in the next mission within available resources. An illustrative example, reliability estimation results, and analysis of optimal selective maintenance scenarios for different levels of budget limitation are provided. [ABSTRACT FROM AUTHOR]

This paper studies the selective maintenance problem for multi-state systems with structural dependence. Each component can be in one of multiple working levels and several maintenance actions are possible to a component in a maintenance break. The components structurally form multiple hierarchical levels and dependence groups. A directed graph is used to represent the precedence relations of components in the system. A selective maintenance optimization model is developed to maximize the system reliability in the next mission under time and cost constraints. A backward search algorithm is used to determine the assembly sequence for a selective maintenance scenario. The maintenance model helps maintenance managers in determining the best combination of maintenance activities to maximize the probability of successfully completing the next mission. Examples showing the use of the proposed method are presented. [ABSTRACT FROM AUTHOR]

In this paper, we will consider the selective maintenance problem for multistate series systems with stochastic dependent components. In multistate systems, the health state of a component may vary from perfect functioning to complete failure. The stochastic dependence (S-dependence) between components is discussed and categorized into two types in multistate context. First, the failure of a component can immediately cause complete failures of some other components in the system. Second, as components deteriorate, the reduced working performance rate of a multistate component affects the state as well as the degradation rate of its subsequent components in series structure. The system reliability is evaluated using an approach based on stochastic process. A cost-based selective maintenance model is developed for the multistate system with S-dependent components to maximize the total system profit, which includes the production gain and loss in the next mission as well as possible maintenance costs for the system. Analyses of systems with independent and dependent components are provided. It is observed that ignoring S-dependence in the system may lead to alternative maintenance decision making and an optimistic estimation of the system performance. [ABSTRACT FROM AUTHOR]

Aims Methylmercury (MeHg) exposure results in increased risk of hypertension and cardiovascular diseases. In this study, we aimed to investigate whether the in vivo exposure of MeHg in mice affects blood pressure and basilar arterial responses to angiotensin II (Ang II) and acetylcholine (ACh), which are important modulators of cerebrovascular autoregulation. Main methods Mice were exposed to MeHg (40 ppm) in drinking water for 21 days. Blood pressure was measured in conscious mice by an indirect tail-cuff method. Functional studies of the isolated arteries' response to vasoactive substances were performed using a micro-organ-bath system. Key findings Systolic and mean blood pressures were significantly increased after 2 and 3 weeks of treatment with MeHg, respectively. Ang II-induced contraction in an isolated basilar artery, which is mediated via Rho-kinase activation, was increased in MeHg-treated mice. ACh-induced relaxation, which is dependent on NO production from the endothelial cells, was decreased in MeHg-treated mice. However, alterations of vascular responses to Ang II and ACh were not observed in the isolated thoracic aorta. Significance This study demonstrated that the cerebral vasculature appears to be particularly sensitive to in vivo exposure of MeHg. Our results suggest that in vivo MeHg increases blood pressure and causes alterations in the cerebrovascular reactivity in response to Ang II and ACh through enhancement of Rho-kinase activity and inhibition of NO bioavailability, respectively. [ABSTRACT FROM AUTHOR]

Three new serratene-type triterpenoids ( 1 – 3 ) and a new hydroxy unsaturated fatty acid ( 13 ) together with nine known compounds ( 4 – 12 ) were isolated from Lycopodiella cernua . The chemical structures were established using NMR, MS, and Mosher’s method. Compound 13 showed the most potent inhibitory activity against acetylcholinesterase (AChE) with an IC 50 value of 0.22 μM. For butyrylcholinesterase (BChE) inhibitory activity, 5 showed the most potent activity with an IC 50 value of 0.42 μM. Compound 2 showed the most potent activity with an IC 50 of 0.23 μM for BACE-1 inhibitory activity. The kinetic activities were investigated to determine the type of enzyme inhibition involved. The types of AChE inhibition shown by compounds 4 , 5 , and 13 were mixed; BChE inhibition by 5 was competitive, while 2 and 6 showed mixed-types. In addition, molecular docking studies were performed to investigate the interaction of these compounds with the pocket sites of AChE. The docking results revealed that the tested inhibitors 3 , 4 , and 13 were stably present in several pocket domains of the AChE residue. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a study on selective maintenance for multi-state series–parallel systems with economically dependent components. In the selective maintenance problem, the maintenance manager has to decide which components should receive maintenance activities within a finite break between missions. All the system reliabilities in the next operating mission, the available budget and the maintenance time for each component from its current state to a higher state are taken into account in the optimization models. In addition, the components in series–parallel systems are considered to be economically dependent. Time and cost savings will be achieved when several components are simultaneously repaired in a selective maintenance strategy. As the number of repaired components increases, the saved time and cost will also increase due to the share of setting up between components and another additional reduction amount resulting from the repair of multiple identical components. Different optimization models are derived to find the best maintenance strategy for multi-state series–parallel systems. A genetic algorithm is used to solve the optimization models. The decision makers may select different components to be repaired to different working states based on the maintenance objective, resource availabilities and how dependent the repair time and cost of each component are. [Copyright &y& Elsevier]

Caesalpinia sappan (C. sappan) is a medicinal plant used for promoting blood circulation and removing stasis. During a screening procedure on medicinal plants, the ethylacetate extract of the lignum of C. sappan (CLE) showed inhibitory activity on arginase which has recently been reported as a novel therapeutic target for the treatment of cardiovascular diseases such as atherosclerosis. CLE inhibited arginase II activity prepared from kidney lysate in a dose-dependent manner. In HUVECs, inhibition of arginase activity by CLE reciprocally increased NOx production through enhancement of eNOS dimer stability without any significant changes in the protein levels of eNOS and arginase II expression. Furthermore, CLE-dependent arginase inhibition resulted in increase of NO generation and decrease of superoxide production on endothelium of isolated mice aorta. These results indicate that CLE augments NO production on endothelium through inhibition of arginase activity, and may imply their usefulness for the treatment of cardiovascular diseases associated with endothelial dysfunction. [ABSTRACT FROM AUTHOR]

Folk experiences suggest natural products in Tetradium ruticarpum can be effective inhibitors towards diabetes-related enzymes. The compounds were experimentally isolated, structurally elucidated, and tested in vitro for their inhibition effects on tyrosine phosphatase 1B (PTP1B) and α-glucosidase (3W37). Density functional theory and molecular docking techniques were utilized as computational methods to predict the stability of the ligands and simulate interaction between the studied inhibitory agents and the targeted proteins. Structural elucidation identifies two natural products: 2-heptyl-1-methylquinolin-4-one (1) and 3-[4-(4-methylhydroxy-2-butenyloxy)-phenyl]-2-propenol (2). In vitro study shows that the compounds (1 and 2) possess high potentiality for the inhibition of PTP1B (IC50 values of 24.3 ± 0.8, and 47.7 ± 1.1 μM) and α-glucosidase (IC50 values of 92.1 ± 0.8, and 167.4 ± 0.4 μM). DS values and the number of interactions obtained from docking simulation highly correlate with the experimental results yielded. Furthermore, in-depth analyses of the structure–activity relationship suggest significant contributions of amino acids Arg254 and Arg676 to the conformational distortion of PTP1B and 3W37 structures overall, thus leading to the deterioration of their enzymatic activity observed in assay-based experiments. This study encourages further investigations either to develop appropriate alternatives for diabetes treatment or to verify the role of amino acids Arg254 and Arg676. [ABSTRACT FROM AUTHOR]

Cassaine diterpenoids amides from the stem bark of Vietnamese Erythrophleum fordii Oliver were screened for their cytotoxic activity against human cancer cells. The cell proliferation assay results showed that, among the active compounds, 3β-acetyl-nor-erythrophlamide (3AEP) exhibited the most potential cytotoxicity against human leukemia HL-60 and KG cells with IC50 values of 12.0 ± 1.2 and 18.1 ± 2.7 µM, respectively. Treatment of 3AEP resulted in the apoptosis of HL-60 cells via the activation of caspase 3, and poly (ADP-ribose) polymerase (PARP). Molecular docking in silico results showed that the 3AEP can bind to both the procaspase-3 allosteric site and the PARP-1 active site, with binding energies of −7.51 and −9.63 kcal/mol respectively. These results indicated that the stem bark of Vietnamese E. fordii and its cassaine diterpenoid amides may be useful in the apoptosis induction of human leukemia cancer cells. [ABSTRACT FROM AUTHOR]

Erythrina variegata L., a member of the Fabaceae family, is a valuable medicinal plant with a rich history of traditional medicinal uses. However, its potential as an antidiabetic agent has remained largely unexplored. In this study, three isoflavonoid compounds, namely eryvarin M (1), eryvarin H (2), and neobavaisoflavone (3), were isolated from E. variegata. These compounds displayed significant inhibitory effects on both protein tyrosine phosphatase 1B and α-glucosidase enzymes. The specific attachment position of the prenyl group to the isoflavonoid skeleton plays a pivotal role in determining the variation in their activity. Moreover, the results obtained from docking simulations corroborate the experimental findings, confirming the robust binding affinities of these metabolites toward the target proteins. The docking analysis further highlights that these compounds exhibit highly negative values of binding-free energies against proteins, indicative of their favorable binding affinities. In addition, the formation of hydrogen bonds in the binding region contributes to their binding interactions. These findings significantly enhance our understanding of the therapeutic potential of both E. variegata and its isoflavonoids as potential inhibitors for diabetes and related metabolic disorders, shedding light on their promising role in the field of diabetes research. [ABSTRACT FROM AUTHOR]

Objectives : To investigate the phytochemical constituents of Vietnamese Dalbergia oliveri and their inhibition of NO production. Methods : The ethyl acetate soluble fraction was subjected to column chromatography using silica gel and Sephadex LH-20 to isolate compounds. The chemical structures of isolated compounds were identified by nuclear magnetic resonance data and comparison with previously reported literature. The anti-inflammation effects of the isolated compounds on the lipopolysaccharide (LPS)-induced NO production in RAW 264.7 cells were measured using the Griess reaction. Results : Nine secondary metabolites (1 − 9) were isolated successfully from the heartwood of D. oliveri. The chemical structures of these compounds were identified as daidzein (1), formononetin (2), 3,7-dihydroxy-4′-methoxyflavone (3), liquiritigenin (4), 3′-methoxydaidzein (5), dalbergin (6), butin (7), sativanone (8), and isoliquiritigenin (9). This is the first time that compounds 1, 3, 5 − 8 have been isolated from D. oliveri. In the NO production inhibition, compounds 7 and 9 exhibited the most potent inhibitory activity, with IC50 values of 7.6 and 11.2 μM, respectively, followed by 3 − 6, with IC50 values from 19.6 to 28.7 μM. Conclusion : The results suggested that D. oliveri and its natural products might exert anti-inflammatory effects due to their NO-inhibiting actions. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the phytochemical constituents of Vietnamese Dalbergia oliveri and their inhibition of NO production. Methods: The ethyl acetate soluble fraction was subjected to column chromatography using silica gel and Sephadex LH-20 to isolate compounds. The chemical structures of isolated compounds were identified by nuclear magnetic resonance data and comparison with previously reported literature. The anti-inflammation effects of the isolated compounds on the lipopolysaccharide (LPS)-induced NO production in RAW 264.7 cells were measured using the Griess reaction. Results: Nine secondary metabolites (1-9) were isolated successfully from the heartwood of D. oliveri. The chemical structures of these compounds were identified as daidzein (1), formononetin (2), 3,7-dihydroxy-40-methoxyflavone (3), liquiritigenin (4), 30-methoxydaidzein (5), dalbergin (6), butin (7), sativanone (8), and isoliquiritigenin (9). This is the first time that compounds 1, 3, 5-8 have been isolated from D. oliveri. In the NO production inhibition, compounds 7 and 9 exhibited the most potent inhibitory activity, with IC50 values of 7.6 and 11.2 μM, respectively, followed by 3-6, with IC50 values from 19.6 to 28.7 μM. Conclusion: The results suggested that D. oliveri and its natural products might exert anti-inflammatory effects due to their NO-inhibiting actions. [ABSTRACT FROM AUTHOR]

Two new xanthones delpyxanthone A (1) and delpyxanthone B (3), together with four known ones, gerontoxanthone I (2), α-mangostin (4), cowanin (5) and cowanol (6) were isolated from the stem bark of Garcinia delpyana. The chemical structures of 1–6 were established mainly using nuclear magnetic resonance (NMR) and mass spectrometry (MS). The anti-inflammatory activity of the isolated compounds was evaluated against lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW264.7 cells in vitro. Compounds 1–4 showed significant inhibitory activity against the LPS-induced NO production in RAW264.7 cells with IC50 values ranging from 14.5 to 28.2 μM, but the others were inactive. The results suggested that G. delpyana and its constituents might be potential anti-inflammatory agents on RAW 264.7 cells. [ABSTRACT FROM AUTHOR]

A new flavanone glycoside, gymnosporioside (1), and three known compounds (2-4) were isolated from the leaves of Gymnosporia stylosa. The structure of gymnosporioside (1) was determined by nuclear magnetic resonance (NMR), time-of-flight mass spectrometry (TOFMS), and circular dichroism (CD) spectral data. The known compounds were identified as prunin (2), acteoside (3), and isoacteoside (4), by comparing the NMR data from this study with those reported in the literature. These known compounds, 2-4, have not been previously isolated from G. stylosa. Their anti-inflammatory activities were evaluated against lipopolysaccharides (LPS)-induced activation of nitric oxide (NO) production in RAW264.7 cells, in vitro. Compounds 3 and 4 showed significant inhibitory activities against LPS-induced NO production in RAW264.7 cells, with IC50 values of 17.8 ± 0.4 and 19.3 ± 0.3 M, respectively. [ABSTRACT FROM AUTHOR]

This study reports the anti-inflammatory activity-guided fractionation of the aerial part of Piper bavinum C. CD. (Piperaceae) that led to the isolation of eight secondary metabolites (1–8). The chemical structures of 1–8 were established mainly by NMR and mass spectra. Compound 5 was isolated from P. bavinum for the first time. All the isolated compounds were evaluated against LPS-induced NO production in macrophage RAW 264.7 cells in vitro. Among them, compound 4 showed the most potent inhibitory activity against the LPS-induced NO production with an IC50 value of 5.2 μM followed by compound 5 that inhibited NO production with an IC50 value of 13.5 μM. In the protein levels, compound 4 suppressed LPS-induced COX-2 and iNOS expressions in a dose-dependent manner. The results suggested that P. bavinum and its constituents might exert anti-inflammatory effects. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate, for the first time, the antagonistic effects of Gingko biloba leaf (GB) and Sophora japonica L. flower bud (SJ) extracts on cerebral vasoconstriction in response to KCl, extracellular Ca, histamine, 5-hydroxytryptamine (5-HT), 9,11-dideoxy-9,11-methanoepoxy prostaglandin (PG) F(U46619) and bradykinin (BK), in order to explain their traditional application for diseases associated with cerebral vasospasm. Isolated porcine basilar arteries (PBA) and endothelial cells from them were used as the study materials. Neither SJ nor GB had any effect on the contractions induced by KCl and extracellular Ca. SJ significantly inhibited the contraction induced by histamine, 5-HT, U46619 and BK, whereas GB inhibited histamine-induced contraction, but had no effects on the contractions induced by 5-HT, U46619 and BK. In the presence of diphenhydramine (a H1 receptor antagonist), ketanserin (a 5-HT2 receptor antagonist) and ONO-3708 (a thromboxane (TX) A2/PG receptor antagonist), the inhibitory effects of these extracts on the contractions induced by histamine, 5-HT and U46619 were abolished. SJ significantly inhibited the contractions induced by BK and PGF, but in the presence of ONO-3708 (10 M) had no effect on them. BK enhanced the production of PGF from cultured PBA endothelium cells, and SJ significantly attenuated this enhancement. These results suggest that SJ and GB have a H1-antagonistic effect, and that SJ also attenuates cerebral vasoconstriction mediated via 5-HT2 and TXA2/PG receptors. These findings appear to explain why SJ has been used traditionally as a therapeutic medication for cerebral vasospasm after cerebral hemorrhage. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance In Vietnamese traditional herbalism, there are conflicting opinions about the effect of Artemisia vulgaris L. (AVL, English name: mugwort) on hypertension. Some ethnic doctors recommend the use of AVL for treatment of hypertension, whereas others advise against it. The purpose of this study was to clarify the pharmacological characteristics of AVL in isolated arteries to explain the conflicts surrounding the use of AVL for treatment of hypertension. Materials and methods We initially performed a functional study using an organ bath system to investigate the effect of AVL extract on isolated porcine basilar artery. We then measured the change in intracellular free Ca 2+ concentration elicited by AVL using cultured smooth muscle cells loaded with the Ca 2+ indicator fluo-4. Finally, using HPLC, we determined the active components in AVL. Results and discussion AVL induced vasoconstriction at resting tension, and endothelial removal enhanced this effect significantly. Pretreatment with PD123319 (an AT 2 receptor antagonist), Nω - nitro - L - arginine (a nitric oxide synthase inhibitor), or both, also enhanced this effect. AVL-induced contraction was competitively inhibited by methiothepin (a 5-HT 1 and 5-HT 2 receptor antagonist) in the presence of ketanserin (a 5-HT 2 receptor antagonist). Removal of extracellular calcium with nifedipine (an L-type Ca 2+ channel blocker) or ruthenium red (a ryanodine receptor blocker) significantly reduced AVL-induced contraction, whereas losartan (an AT 1 receptor antagonist) and diphenhydramine (a H 1 receptor antagonist) had no effect on this contraction. AVL increased the intracellular free Ca 2+ concentration in cultured cells, and this increment was inhibited by methiothepin. HPLC analysis revealed that the retention time of the first peak in the AVL profile was similar to that of the 5-HT standard, and that addition of 5-HT to the AVL sample enhanced this peak. On the other hand, AVL induced endothelium-independent relaxation under precontracted conditions with 60 mM KCl. Captopril (an angiotensin converting enzyme inhibitor), atenolol (a β 1 receptor antagonist) and cimetidine (a H 2 receptor antagonist) had no effect on this relaxation. In Ca 2+ -free 60 mM KCl-containing solution, pretreatment with AVL significantly inhibited CaCl 2 -induced contraction. Conclusion For the first time, the present study has demonstrated that AVL has two opposite effects, contraction and relaxation, on isolated artery, which may help to explain the conflicting indications for AVL in traditional herbalism. 5-HT is a significant factor affecting artery contraction in the presence of AVL. [ABSTRACT FROM AUTHOR]

Homoisoflavonoids constitute a small class of natural products. In the present study, we investigated the anti-inflammatory effect of sappanone A (SPNA), a homoisoflavanone that is isolated from the heartwood of Caesalpinia sappan (Leguminosae), in murine macrophages. SPNA inhibited the production of nitric oxide (NO), prostaglandin E 2 (PGE 2 ) and interleukin-6 (IL-6) as well as the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and IL-6 in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Moreover, SPNA protected C57BL/6 mice from LPS-induced mortality. Treatment of RAW264.7 cells with SPNA induced heme oxygenase (HO)-1 protein and mRNA expression and increased nuclear translocation of the nuclear factor-E2-related factor 2 (Nrf2) as well as the expression of Nrf2 target genes such as NAD(P)H:quinone oxidoreductase 1 (NQO1). Knockdown of Nrf2 by siRNA blocked SPNA-mediated HO-1 induction. SB203580, p38 mitogen-activated protein kinase (MAPK) inhibitor, blocked SPNA-induced HO-1 expression and nuclear translocation of Nrf2, suggesting that SPNA induces HO-1 expression by activating Nrf2 through the p38 MAPK pathway. Consistent with the notion that the Nrf2/HO-1 pathway has anti-inflammatory properties, inhibiting HO-1 significantly abrogated the anti-inflammatory effects of SPNA in LPS-stimulated RAW264.7 cells. Moreover, SPNA suppressed LPS-induced nuclear factor κB (NF-κB) activation via inhibiting Ser 536 phosphorylation and transcriptional activity of RelA/p65 subunit of NF-κB. Taken together, these findings suggest that SPNA exerts its anti-inflammatory effect by modulating the Nrf2 and NF-κB pathways, and may be a valuable compound to prevent or treat inflammatory diseases. [ABSTRACT FROM AUTHOR]

The article discusses the cytotoxic activity of phenolic compounds including caesalpiniaphenols G and H from Vietnamese caesalpinia sappan, a species in the legume family Fabaceae. Topics discussed include potent inhibitory activity of the phenolic compounds against the HL-60 cancer cell lines, extraction and isolation of C. sappan and cytotoxic activity assay of the compound.

[Display omitted] • Dysoxylum tpongense Pierre (local name 'Huynh Dan Bap') (Meliaceae). • Anti-inflammatory activities against Liver X receptor (LXR) and NF-κB activation factors in HepG2 cell line. • Cabraleahydroxylactone (derivatives (5-6) and stigmast-4-en-3-one (10) showed remarkable inflammatory inhibition of the LXR activation in HepG2 cells. • Aglinin C derivatives (1- 2) and 24- epi -cabraleadiol (4) showed the most inhibitory activity for the TNF-α-induced NF-κB activation in HepG2 cells. • Stigmast-4-en-3-one (10) is a potential LXR – pathway selective agonist. Dysoxylum tpongense Pierre (local name 'Huynh Dan Bap') belonging to family Meliaceae, is a tree (3–10 m height), distributed in the mountainous areas (ca. 1000 m a.s.l.) in North Vietnam. From the dichloromethane fraction of the methanol extract of the leaves and stems of this plant, six dammarane triterpenes, one furanoid diterpene together with three sterols were isolated. Evaluation of biological activities of isolated compounds showed that cabraleahydroxylactone (5), cabraleahydroxylactone 3-acetate (6), and stigmast-4-en-3-one (10) possessed an anti-inflammatory effect against Liver X receptor (LXR) activation in HepG2 cell line model with IC 50 values of 20.29 ± 3.69, 24.32 ± 2.99, and 7.09 ± 0.97 (μM), respectively. While three other triterpenoid compounds aglinin C 3- acetate (1), aglinin C (2), and 24- epi -cabraleadiol (4) presented the most significant inhibitory effect against TNF-α induced NF-κB activation in HepG2 cell line in a dose-dependent manner with IC 50 values of 12.45 ± 2.37, 23.32 ± 3.25, and 13.95 ± 1.57 μM, respectively. As stigmast-4-en-3-one (10), with structure closely similar to cholesterol, acted selectively on LXRs but not on NF-kB activation pathway, this suggests that stigmast-4-en-3-one (10) can be potentially applied as an agonist on LXR signaling pathway. Pathways LXRs-NF- κ B-iNOS expression have a close relationship and play a crucial role in proceeding metabolic abnormalities like atherosclerosis, obesity, inflammation, etc. Thus, the findings showed that dammarane-type triterpenoids from D. tpongense are worthy of further investigation for potential LXR agonists and potent anti-atherogenic agents against atherosclerotic lesion progression. [ABSTRACT FROM AUTHOR]

Cassaine diterpenoids as erythrofordins A-C (1 – 3), pseudo-erythrosuamin (4), and erythrofordin U (5) isolated from the leaves of Vietnamese Erythrophleum fordii Oliver were tested cytotoxic activity against human leukemia cancer cells. The results showed that these metabolites exhibited dose-dependent cytotoxicity against human leukemia HL-60 and KG cells with IC 50 values ranging from 15.2 ± 1.5 to 42.2 ± 3.6 µM. Treatment with erythrofordin B led to the apoptosis of HL-60 and KG cells due to the activation of caspase 3, caspase 9, and poly (ADP-ribose) polymerase (PARP). Erythrofordin B significantly increased Bak protein expression, but downregulated the anti-apoptotic protein Bcl-2, in HL-60 cells. In silico results demonstrated that erythrofordin B can bind to both the procaspase-3 allosteric site and the PARP-1 active site, with binding energies of −7.36 and −10.76 kcal/mol, respectively. These results indicated that the leaves of Vietnamese E. fordii , which contain cassaine diterpenoids, can induce the apoptosis of human leukemia cancer cells. [ABSTRACT FROM AUTHOR]

Seven pimarane diterpenes (1–7) were isolated from Orthosiphon stamineus Benth. by assay-guided isolation. All of the isolates possessed a 2-deoxy-2-((7-nitro-2,1,3-benzoxadiazol-4-yl)amino)-d-glucose uptake effect in 3T3-L1 adipocytes at concentrations of 5 and 10 μM. Most of them showed potent inhibition against protein tyrosine phosphatase 1B with IC50 values ranging from 0.33 to 9.84 μM. In the kinetic study, all inhibition types were exposed for the examined potencies, including mixed-competitive (1), non-competitives (3 and 5), competitive (6), and uncompetitive (7). The results suggested that O. stamineus and its pimarane diterpenes might exert the hypoglycemic effect via the insulin signaling pathway targeting inhibition of protein tyrosine phosphatase 1B (PTP1B) activity. [ABSTRACT FROM AUTHOR]

isolation and structure elucidation of madhumidine A (I) [ABSTRACT FROM AUTHOR]